The Messenger 167
The Messenger 167
The Messenger 167
1
ESO
2 0%
Canadian Astronomical Data Centre
(CADC), National Research Council of
2012 2013 2014 2015 2016
Canada, Victoria, Canada
3
National Radio Astronomy Observatory
(NRAO), Charlottesville, USA proposal process, one of the main pur- in the world at that time. As astronomy
4
Joint ALMA Observatory (JAO), Vitacura, poses of a science archive is indeed to will inevitably transform into a science
Santiago, Chile enable independent research. where the largest fraction of observed
5
National Astronomical Observatory of pixels will never be looked at by a human,
Japan (NAOJ), National Institutes of For only a very small fraction (of the machine-aided analysis will inevitably
Natural Sciences, Tokyo, Japan order 13 %) of the total yearly opera- increase in importance. This approach
6
National Research Council of Canada, tional cost of a facility, substantial addi- includes scientific pre-analysis (for exam-
Victoria, Canada tional scientific progress can be obtained ple, the ALMA Data MIning Toolkit,
through public provision of a science ADMIT: Teuben et al., 2015), remote visu-
archive. This is, for example, true in the alisation (for example, the Cube Analysis
Science archives help to maximise case of the Hubble Space Telescope and Rendering Tool for Astronomy,
the scientific return of astronomical (HST), where publications making use of CARTA: Rosolowsky et al., 2015) and
facilities. After placing science archives archival data have by now outnumbered remote analysis (code-to-data), as well
into a slightly larger context, we the publications of PI observations by as analysis based on machine learning.
describe the current status and capa the proposing teams. Romaniello et al. In particular, deep learning is currently
bilities of the ALMA Science Archive. (2016) also report the growth of an ESO witnessing an epochal change and dra-
We present the design principles and archive community, where almost 30 % matic new possibilities can be expected
technology employed for three main of users downloading data from the Sci- over the next few years. Successful
contexts: query; result set display; and ence Archive Facility (SAF) have never approaches, like automatic caption gen-
data download. A summary of the been PI or co-investigator of an ESO pro- eration for images2 and human-quality
ALMA data flow is also presented as posal. For the still very young Atacama astronomical object classification
are access statistics to date. Large Millimeter/submillimeter Array (Dieleman et al., 2015), give an indication
(ALMA) facility and its ALMA Science of the future prospects in this area. A
Archive1, we can report a rapidly increas- powerful well-characterised science
Introduction ing fraction of publications making use archive is the basis of such data-mining.
of archival data (Figure 1), already reach-
The overall success of an astronomical ing 16 % (or 27 % including publications Depending on the nature of the project
facility is measured by the quality and from Science Verification data) in 2016 and its goals, and notwithstanding the
quantity of science produced by its com- (see also Stoehr et al., 2015). remark about the small operational costs
munity. By helping the principal inves of archives, the fraction of the total cost
tigators (PIs) and archival researchers of The requirement that data be well that astronomical facilities spend on
the facility to easily discover, explore and described and easy to discover through data management is expected to slowly
download the data they need, a science science archives can be expected to increase. An extreme showcase of this
archive helps to maximise the scientific grow rapidly in the future, as the amount evolution, admittedly in a different con-
return and thus to increase the success of data increases exponentially. For text, is the Large Synoptic Survey Tele-
of the facility. In addition to the delivery of example, we estimate that the fully opera- scope (LSST), where 52 % of the total
data to PIs, provision of data-persistence tional Square Kilometre Array (SKA) will survey cost of $1.25 billion is expected
for independent verification of scientific deliver around 200 TB per year of sci- to be spent on data management3.
results and duplication checking in the ence images for every active astronomer
Querying cations and proposals. Currently 31 input show all public, but unpublished,
fields are available, of which 14 are observations. This enables the ALMA
Searching astronomical data via search numerical. For the input fields, a variety project to survey non-publishing PIs
interfaces differs greatly from standard of operators can be used (equals, like, and to investigate the reasons why they
web searches, such as that provided by or, <,>, range, not, ). The query is could not publish (Stoehr et al., 2016);
Google. Whereas the latter solve the completely unscoped, that is we do not show all publications making use of
problem find words in a collection of text require users to first query by position or full-polarisation data;
documents, searches in astronomical object name, or even require any con- show the proposals, data from which
archives are inherently multi-dimensional straint at all. Hitting search without con- were used in publications having
and many parameters are numerical straints will return the full holdings. This molecular hydrogen in the publication
rather than textual. In that sense, astro- choice also has the positive side-effect abstract;
nomical search engines are closer to that the multi-parameter search capability show all publications making use of
product-finder search engines4. Moreo- is automatically extended to all the more data from the programme Discs
ver, the target audience of astronomical rarely used columns in the results table around high-mass stars;
searches is extremely homogeneous which do not show up on the query form, show all observations of active galaxies
and highly educated, as the vast majority but for which we still provide a sub-filtering reaching line sensitivities of 1 mJy/beam
of the users will hold degrees in astron- capability on the results page, like, for at 10 km s 1 resolution or continuum
omy or physics. example, whether or not an observation sensitivities of 0.1 mJy/beam.
is a mosaic or which antenna types were
With this consideration in mind, our main employed. The user can choose to dis- Maximally physical query
design principles in the ALMA Science play the results of any query in a view Great efforts have been made to allow
Archive are: access to the full parameter where one row corresponds to one constraints to be placed on as many
space; a maximally physical query; and, observation, or to one project, or even to physical parameters as possible, accord-
at the same time, minimal interaction one publication. Given the homogeneous ing to the main properties a photon
cost. We consider each of these princi- and educated audience, we intentionally carries: position, energy, time and polari-
ples in turn. chose not to provide an additional basic sation; see also Stoehr et al. (2014).
interface. Examples are the angular and spectral
Full parameter space resolutions, the field of view, frequencies,
In the ALMA Science Archive we provide This multi-dimensional unscoped inter- bandwidth and the largest angular scale.
the capability to place query constraints face permits powerful queries to be exe- In addition, users can now also query
simultaneously on observations, publi cuted. For example: on the estimated sensitivity expected to
be reached for line or continuum obser- ALMA archive context this means reduc- In contrast to the one-line interfaces of
vations. This value, corresponding to the ing the cost of reading, identifying, as word-in-text searches, the knowledge
limiting magnitude in optical observa- well as memorising, the structure and of the search space (what constraints
tions, is a particularly useful constraint. functionality of the interface. It also can be given) on advanced interfaces is
In addition, we capture the physical con- includes reducing the mouse travel dis- not trivially acquired by the users. There-
tent of the observations from the users, tance and the number of mouse clicks, fore the first task of any such interface
offering the scientific keywords specified as well as ensuring that users should must be to explain that search space. In
when the proposal was written and the not be forced to leave the page during order to reduce the interaction cost of
scientific categories, as well as allowing their interaction with the interface. A key this process, we visually group the con-
searches through the titles and abstracts to reducing interaction cost is to only cepts, order them by importance within
of the proposals and also publications provide the information to the users that the groups, remove everything that is
making use of ALMA data. they need at a given moment during the unnecessary and make sure that the
interaction with the interface (see also entire context fits onto the screens even
Providing searches on physical concepts Stoehr et al., 2012 and Stoehr, 2017 in of small laptops. The interface is trimmed
rather than observatory-specific jargon press) and to re-use the existing web for responses that are fast enough, so
(for example, angular resolution rather knowledge and habits of users. that the relevant context still resides in
than array-configuration) is especially the users short-term memory6, further
important, as ALMAs mission explicitly For the ALMA Science Archive interface lowering the interaction cost.
includes enabling non-radio astronomers (Figure 2), these principles mean, for
to use the facility. example, to open input fields only when
needed, to close them unless a value Query results
Minimal interaction cost has been entered, to place the buttons
Although, as shown above, astronomical always at the same location on the The second step of every search is the
searches are quite different from typical pages, to provide help directly on the exploration of the results to identify the
web searches, wherever possible classi- page, to show information for each input assets in which the user is finally inter-
cal web-design principles have been field unobtrusively in a tooltip when the ested. For the ALMA Science Archive we
applied. The most important of those user is entering a value, and to have show the observations in their astronomi-
principles is to reduce the interaction those tooltips contain clickable examples. cal context, using the observational foot-
cost of the user to a minimum5. In the prints and the AladinLite7 (Bonnarel et al.,
250
Figure 6. (Lower left) Time between the public avail-
ability of data and their download. Data are down-
200 loaded rapidly after they become public (12 months
for most data, 6 months for Directors Discretionary
150 Time data) and remain heavily requested for a long
period.
100
3000 References
Number of tar files
The ALMA Science Archive is a single- have led to 588 publications so far. Cur- Links
page web application deployed on rently the ALMA Science Archive is grow- 1
ALMA Science Archive: http://almascience.org/aq
Apache Tomcat, built using Java, the ing by about 15 TB every month (see Fig- 2
Neural image caption generator: https://research.
Spring framework, JQuery and Oracle ure 5). Data are downloaded quite quickly google.com/pubs/pub43274.html
12c. It is a deliverable of ESO to the for archival research after they become 3
LSST data management: http://euclidska.physics.
ALMA project. We rely heavily on the public and remain of interest for a long ox.ac.uk/Euclid-SKA /160913/Tyson.pdf
4
Product-finder search engines: http://www.idealo.
OpenCADCTap10 software package, period (Figure 6). This is especially signifi- co.uk/filter/3751/laptops.html?q=notebook
which provides the VO layer on top of cant given that ALMA is still a very young 5
User interaction cost: https://www.nngroup.com/
the database holdings. The query inter- facility: the amount of data that is public articles/interaction-cost-definition/
6
face is a client to this VO layer using the for more than 40 months, for example, is Web and short-term memory: http://www.
nngroup.com/articles/short-term-memory-and-
Astronomical Data Query Language much smaller than the amount of data web-usability
(ADQL11) as the interface language. that is public for more than 15 months. 7
AladinLite: http://aladin.u-strasbg.fr/AladinLite
8
ADS: https://ui.adsabs.harvard.edu/#search/
q=full%3AALMA&sort=date%20desc%2C%20
bibcode%20desc
Holdings and statistics Outlook 9
Python astroquery:
https://astroquery.readthedocs.io/en/latest
At the time of writing, the ALMA Science While the query functionality of the ALMA 10
OpenCADCTap package:
Archive contains data from about 32000 Science Archive can now compete with https://github.com/opencadc/tap
11
ADQL: http://www.ivoa.net/documents/latest/
observations stored as 280 TB and dis- other astronomical archives, substantial ADQL.html
tributed over 18 million files. Those data work is still required over the next few
1
ESO ESO and several European partners
(including Chalmers University in Sweden,
the Science and Technology Facilities
ALMA Band 5 (163211 GHz) was Council [STFC] in the UK and the Univer-
recently commissioned and Science sity of Chile) were awarded funding by
Verification (SV) observations were the European Commission under the
obtained in the latter half of 2016. A pri- EUs Sixth Framework Programme (FP6)
mary scientific focus of this band is the to develop prototypes of Band 5. A set of
H2O line at 183.3GHz, which can be six prototype receivers was produced by
observed around 15 % of the time when the Group for Advanced Receiver Devel-
the precipitable water vapour is suffi- opment (GARD) at Chalmers University in
ciently low (<0.5mm). Many more lines collaboration with the Rutherford Appleton
are covered in Band5 and can be Laboratory (United Kingdom) under an
observed for over 70 % of the time on EU FP6 contract and delivered to ALMA
Chajnantor, requiring similar restrictions in 2012 (Billade et al., 2012). ALMA
to those for ALMA Bands 4 and 6. accepted the ESO proposal to outfit all Figure 1. An assembled ALMA Band 5 receiver
c artridge, shown courtesy of NOVA/GARD.
Examples include the H218O line at 66 antennas with Band 5 receivers in
203GHz, some of the bright (32) lines 2012.
of singly and doubly deuterated forms ments, most notably on the Atacama
of formaldehyde, the (21) lines of The production of the revised and opti- Pathfinder EXperiment (APEX) telescope
HCO+, HCN, HNC, N2H+ and several of mised full complement of 73 Band5 as part of the Swedish-ESO PI receiver
their isotopologues. A young star- cartridges started in 2013, with produc- for APEX (SEPIA) project. The SEPIA
forming region near the centre of the tion shared between GARD and the Band 5 receiver was commissioned at
Milky Way, an evolved star also in our Nederlandse Onderzoekschool Voor APEX in 2016 and Immer et al. (2016)
Galaxy, and a nearby ultraluminous Astronomie (NOVA), who were jointly describe the instrument and some of the
infrared galaxy (ULIRG) were observed responsible for the production and the commissioning and SV observations.
as part of the SV process and the data integration of the Cold Cartridge Assem- Other Band 5 pre-production cartridges
are briefly described. The reduced data, bly of the receiver, and the National Radio will be installed on the Atacama Submil-
along with imaged data products, are Astronomy Observatory (NRAO) in the limeter Telescope Experiment (ASTE)
now public and demonstrate the power USA, who provided the Warm Cartridge on Chajnantor, and on the Large Latin
of ALMA for high-resolution studies of Assembly. The receivers are dual polari- A merican Millimeter Array (LLAMA) in
H2O and other molecules in a variety of sation SIS (superconductor insulator Argentina. One is kept at ESO for public
astronomical targets. superconductor) mixers used in a side- display. The installation of the production
band-separating (2SB) configuration and Band 5 receivers started at ALMA during
operated with all-reflective cold (<4K) 2015 and 2016 and the first fringes were
One of the bands of the Atacama Large optics. The measured system tempera- obtained in July 2015. At the time of
Millimeter/submillimeter Array (ALMA) ture of the production receiver is <50K writing 45 Band5 cartridges have been
that was not initially produced during over 80 % of the band (Belitsky et al., delivered to the ALMA project and 32 of
construction of the observatory and was 2017), a figure significantly better than the these are integrated in ALMA Front Ends.
not available when the array was officially original ALMA specifications for this
inaugurated in 2013 was Band5, cover- receiver band, and achieved thanks to Band 5 will be offered as a standard
ing the frequency range 163211GHz extensive optimisation work undertaken mode in all available array configurations
(1.91.4mm). Band 5 was one of the at GARD following the production of the (including the ALMA Compact Array,
three frequency ranges originally envi- six prototype receivers. Figure1 shows ACA) in ALMA Cycle 5. Current plans are
sioned for ALMA, but deferred from one of the Band5 cartridges. for Band 5 to be available for science
the construction project to the develop- observations starting in the second half
ment programme. The other two are: Several of the six prototype Band5 of the cycle (March 2018), following com-
the 3550GHz frequency range (Band1, receivers were installed in other instru- missioning of all the receivers.
and modes for SV focuses on testing 175 180 185 190 195
challenging or novel calibration schemes
to ensure smooth science operations. As
per ALMA policy, the intention was to
select targets with previous H2O observa-
tions in order to enable a careful compar-
ison with the ALMA results; in all cases 0
195 200 205 210 215
the targets were also common to APEX
Frequency (GHz)
SEPIA Band 5 observations. In the case
of ALMA Band5SV, one extragalactic Figure 2. Superposition
5000 au of ALMA (black) and
target with previously detected H2O emis-
APEX (blue) spectra
sion was selected Arp 220, a prototypi- from part of the Band 5
cal luminous infrared galaxy along with full spectral scan of the
two Galactic targets: the molecular cloud Sgr B2 star-forming
region (from Baobab Lu,
complex near the Galactic Centre, Sagit-
Katharina Immer, Anita
tarius B2, selected for a full-band spectral 16 Richards, Ana Lopez-
scan; and the evolved supergiant star Sepulcre, Lydia Moser
VYCMa, chosen to demonstrate the line
Dec (J2000)
7.8
with the limited set of available baselines, 0.5
5.7
the imaging of this dataset is challenging, 4.0
and the image fidelity is relatively low 0.0 2.6
compared to typical ALMA observations. 1.4
The importance of this SV observation 0.5 0.6
was to provide a complete spectral scan 0.2
of the whole of Band 5 to test the ability 0.5 0.0 0.5
0.0
to calibrate across the full band in varying RA offset (arcsecond)
atmospheric absorption conditions.
Figure 3. Spatially resolved velocity slices of the stellar magnetic field strength and mor-
polarisation vectors in VY CMa superimposed on the
Figure 2 (upper) shows the ALMA and phology. This may be important for
polarised intensity image for the SiO maser line
SEPIA spectra overlaid. A wealth of around 172.5GHz (from a report released with the understanding the mass-loss process
molecular lines is revealed at a velocity ALMA data by Ivn Mart-Vidal, Wouter Vlemmings from these stars, and the structures
resolution of ~1km s 1, many of which and Tobia Carozzi2 ). observable in the circumstellar enve-
remain to be identified. For part of the lopes. For lower mass stars, such as
observing time the H2O transmission was It is expected to eventually explode as a those on the Asymptotic Giant Branch,
low enough to map some water maser core collapse supernova. It has a com- ALMA polarisation observations may
emission clumps associated with the plex, extended and outflowing dusty and additionally provide information on the
massive star formation (Figure 2, lower). molecular envelope with H2O and SiO processes leading to planetary nebulae.
The comparison between the APEX and maser emission detected. The SV obser- In the SV dataset, one of the results is
ALMA spectra shows that the brightest vations concentrated on measuring the that both the continuum and the SiO and
lines, associated with more extended polarisation in continuum and in the H2O H2O maser emission towards VYCMa
emission, are not fully recovered in the and SiO maser lines (at 183.3 and around are confirmed to be polarised. Maps of
interferometric spectrum, because of the 172.5GHz, respectively). Fifteen ALMA the polarisarisation vectors in SiO maser
aforementioned limitations in the (u,v) 12-metre antennas and baselines up to emission are shown in Figure3.
coverage. The compact structures, 0.48km were employed and again there
including all absorption lines against the were previous APEX observations with Arp220
bright and compact continuum emission, which to compare. Arp 220 is the closest (at ~ 78Mpc) ultra-
are well matched. luminous infrared galaxy (~ 41012 L )
This is the first ALMA SV line polarisation representing an ongoing merger. The
VY CMa dataset obtained and it was used to core has a very high star formation rate
VY Canis Majoris is a red supergiant star check the observation and data reduc- and is a rich source of molecular emis-
of spectral type M5 in a phase of strong tion procedures for this important sion. It has been extensively observed at
mass loss (<10 4 M yr 1). The star is observing mode, expected to be used mm and radio wavelengths and displays
very extended and of high luminosity for a variety of science cases and astro- H2O maser emission (at 22, 183 and
(~ 3105 L, for a distance of 1.2 kpc) nomical targets. For supergiant stars like 325GHz). The 183 GHz water emission
and the 2532 M progenitor star is now VYCMa, it is anticipated that ALMA line was previously observed using the
evolving blueward in the Hertzsprung- polarisation observations will make trans- Institut de Radioastronomie Millimtrique
Russell diagram (Wittkowski et al., 2012). formational advances in understanding (IRAM) 30-metre telescope and APEX.
30 m (2005)
200
30 m (2014)
Arp 220 has a double nucleus with the tion problems and finalise the calibration Itziar de Gregorio, Antonio Hales, Violette Impellizzeri,
Andres Felipe Perez Sanchez, Neil Phillips, Adele
peaks of molecular emission separated and data release products. On 7Decem-
Plunkett, Giorgio Siringo, Satoko Takahashi, the JAO
by 1.1 arcseconds and the Band 5 obser- ber 2016, the Band 5 raw data, calibrated Extension and Optimisation of Capabilities (EOC)
vations (beam size 0.7 arcseconds) data and reference images, as well as the Team and the JAO Department of Science Opera-
resolved the H2O emission into the east calibration scripts and detailed documen- tions (DSO) team members who performed the
observations. The fantastic Band 5 receivers we
and west nuclei (see Figure4). The tation explaining the imaging and calibra-
have on ALMA would have not been possible without
western component is brighter while the tion procedures, were publicly released the preproduction effort funded by the EU FP6 at
eastern one has a steep velocity gradient. on the ALMA SV page1. At the Band 5 GARD and RAL, and without the cartridge optimisa-
Knig et al. (2017) compared the H2O Workshop in February 2017 (see the fol- tion and production effort at GARD, NOVA, and
NRAO, and the Integration and Verification team on
183.3GHz line profile with previous lowing article by de Breuck et al., p. 11),
site in Chile supported by ESO, with contributions
observations using the IRAM 30-metre analysis and results from these SV obser- from the National Astronomical Observatory of
telescope (Cernicharo et al., 2006) and vations were presented and discussed. Japan (NAOJ). We thank Jeremy Walsh for his work
the SEPIA Band 5 receiver on APEX on this article.
(Galametz et al., 2016). The line profiles These SV observations allowed us to vali-
are remarkably similar over a period of date and release the science operations References
> 10 years (see Figure 5). This is perhaps procedures to obtain successful ALMA
unexpected for maser lines, which charac- Band 5 observations and resulted in the Belitsky, V. et al. 2017, A&A, in preparation
Belloche, A. et al. 2013, A&A, 559, 147
teristically change in strength on time- inclusion of Band 5 as a standard mode
Billade, B. et al. 2012, IEEE Trans. Terahertz
scales of months to years. It is therefore in the Cycle 5 call for proposals. The Science Technology, 2, 208
suggested that the H2O profile represents datasets are now being used by astrono- Cernicharo, J. et al. 2006, ApJ, 646, L49
the emission of many unresolved maser mers in the community to perform scien- Galametz, M. et al. 2016, MNRAS, 462, L36
Immer, K. et al. 2016, The Messenger, 165, 13
spots within the star-forming complex, so tific a
nalysis and to prepare for their own
Knig, S. et al. 2017, A&A, submitted,
that, while individual masers vary, the observing proposals in the forthcoming arXiv:1612.07668
aggregate profile does not (Knig et al., ALMA Cycle. Wittkowski, M. et al. 2012, A&A, 540, 12
2017).
Links
Acknowledgements
Data Release Obtaining, validating and releasing the ALMA Band5
1
A LMA SV Band 5 data release: targets:
https://almascience.eso.org/alma-data/science-
SV data was a team effort involving a large number
verification
After the initial data collection and of people at ESO, the EU ARC Network and the Joint 2
Band 5 Polarisation Calibration Information:
assessment, an intensive workshop was ALMA Observatory (JAO). We thank for their key
https://almascience.eso.org/almadata/sciver/VYC-
contributions Tobia Carozzi, Simon Casey, Sabine
held at Chalmers University, Sweden Knig, Ana Lopez-Sepulcre, Matthias Maercker,
MaBand5/VYCMa_Band5_PolCalibrationInforma-
in October 2016 where participants from Ivn Mart-Vidal, Lydia Moser, Sebastien Muller, Anita
tion.pdf
across the European ALMA Regional Richards, Daniel Tafoya, Wouter Vlemmings, Allison
Centre (ARC) worked to solve the calibra- Man, John Carpenter, Paulo Cortes, Diego Garcia,
Carlos De Breuck1 of being installed in ALMA and the pre ALMA, a full set of optimised receivers
Leonardo Testi1 vious article (Humphreys et al., p. 7) was built by GARD and the Nederlandse
Katharina Immer1 describes the Science Verification (SV). Onderzoekschool Voor Astronomie
The timing was therefore right for a work- (NOVA) in Groningen, with the local oscil-
shop on the Band 5 science already lators (LO) and warm electronics built
1
ESO achieved with SEPIA. by the National Radio Astronomy Obser-
vatory (NRAO) in the USA.
The goal of the meeting was to discuss
The workshop provided an overview and highlight the role of APEX as an Giorgio Siringo from the Joint ALMA
of the wide range of results from the ALMA complement and to encourage Observatory (JAO) gave a detailed pro-
first two years of science operations European ALMA users to focus on the gress report of the installation and veri
with the ALMA Band 5 (163211 GHz) science that will be enabled by the new fication of the Band 5 receivers at ALMA.
receiver in the Swedish ESO PI Instru- Band 5 receivers ahead of the ALMA Production and delivery of the receiver
ment for APEX (SEPIA) ahead of the Cycle 5 call for proposals. The workshop cartridges is expected to be completed
ALMA Cycle 5 call for proposals, when was attended by more than 50 astrono- (including all spares) by the end of 2017,
the Band 5 receivers will be offered for mers and submillimetre instrument build- while completing the installation and veri-
the first time. The frequency range of ers (see Figure 1) and also featured some fication for use within the ALMA antennas
the Band 5 receiver has never been fully SEPIA science with the Band 9 receiver. depends on the scheduling of Front End
covered by existing receivers; the talks maintenance at the Observatory. The
presented at the workshop illustrate the current estimate is that Cycle 5 science
importance of several lines in this fre- Development of the Band 5 receivers operations for Band 5 receivers will com-
quency range that provide crucial diag- mence in March 2018 (see Humphreys et
nostics of the interstellar medium. As explained by Victor Belitsky, who al., p. 7).
gave the opening invited talk, the idea of
building a receiver to cover the frequency
SEPIA, the Swedish ESO PI Instrument gap between ALMA Bands 4 and 6, and Evolved star science with Band 5
for the Atacama Pathfinder EXplorer across the 183.3GHz atmospheric H2O
(APEX) was developed around a pre- absorption line, started in 2005. Thanks One of the areas where the Band 5
production Band 5 receiver (157212GHz) to a specific grant as part of the Euro- receiver has already made a significant
built for the Atacama Large M illimeter/ pean Unions Sixth Framework Program impact in its two years of science oper
submillimeter Array (ALMA). It was (FP6), a first set of six pre-production ations at APEX is the field of evolved
installed on APEX in early 2015 (Immer receivers was built by the Group for stars (overview talk by Elvire De Beck).
et al., 2016), and is already being used Advanced Receiver Development (GARD) The outer layers of these stars are labo
by European astronomers to reveal the at the Chalmers University of Technology ratories where a wide range of molecules
new science that can be done in this in Gothenburg in collaboration with the are formed and fed into the interstellar
relatively unexplored frequency band. Rutherford Appleton Laboratory (Billade medium (ISM) through stellar winds.
The Band 5 receivers are in the process et al., 2012). After successful testing at Although no CO lines are present in
Luis Calada/ESO
TMB (K)
(Elvire De Beck). By combining the con- 0.4
intensity and line profile) of this masing 0.3 H 213CO 3(1,3)2(1,2) IRAM
line in Arp 220 (Knig et al., 2017); see 0.2
Figure 5 of Humphreys et al., p. 7.
0.1
0
Other gas tracers in Band 5 0.1
HDCO 3(2,1)2(2,0) SEPIA
The first spectral line surveys in Band5 0.05
have already shown a remarkable rich-
ness of molecular lines, as illustrated, for 0
example, by the Sgr B2(N) spectrum
observed with both ALMA and SEPIA 0.1
(Fig. 5 of Humphreys et al. p. 10), or the HDCO 3(2,2)2(2,1) SEPIA
D-Dor survey shown in De Becks talk. 0.05
TMB (K)
In star-forming regions, the brightest lines Kirsten Knudsen and Maria Strandet the redshift coverage of the CO(21) line
in Band5 are the 21 transitions of HCN, summarised the role of Band5 for high- out to z=0.46, and SEPIA has already
HNC and HCO+. In a pilot survey of redshift science, highlighting respectively started to fill the existing redshift gap
pointed observations within the LMC and the CO and fine structure lines that move (from Edo Ibar). To cover the CO spectral
SMC, Maud Galametz found large spatial into the frequency range of Band5 for line energy distribution, continuous fre-
variations between the HCO+(21) and different redshift ranges. Band5 extends quency coverage is essential (from Bitten
0.4
0.2
0 SDP.11 [C II]
0.4 400 SEPIA B9
0.2
0.2
0
0.4 200
0.2
0
0.4 CO J = 43
0.2 PdBI
0 10
0.4 Flux density (mJy)
0.2
0
0.4 5
0.2
0
50 50 50 50
Velocity (km s 1) 0
Gullberg). For fine-structure lines, the lines, such as the z~1.9 [CII] lines Figure 5. The [CII] 158m line detected with the
Band 9 receiver of SEPIA in the z=1.8 dusty star-
most important lines shifting into Band5 observed during SV by Zhi-Yu Zhang
forming galaxy SDP.11 (Zhang et al., in prep.). The
at 1.33<z<2.11 and 2.84<z<4.13 (Figure5), and the tentative [OIII] 88m velocity profile in this short SEPIA observation is fully
are the [CI] 609m and 370m lines, detections by Carlos De Breuck. The consistent with the IRAM Plateau de Bure CO(43)
respectively. Paola Andreani and Matt SgrB2(N) spectral scan highlighted the data of Oteo et al. (2017).
Bothwell highlighted the importance of difficulty of using the current double
the [CI] line as an alternative tracer for sideband (DSB) receiver for line-rich
the H2 mass, and reported several SEPIA sources, due to overlapping signal com- how to optimally use the query forms.
detections. By filling the frequency gap ing from the two sidebands (Katharina Future developments (for example, better
in the ALMA coverage, the SEPIA Band5 Immer). With future upgrades to a side- visualisation tools) were also mentioned
receiver has also manifested itself as an band-separating receiver and a doubling on how to better mine the ALMA and
ideal follow-up instrument for ALMA, of the spectral bandwidth, we can hope APEX data archives.
confirming ambiguous redshifts obtained for an APEX pathfinding role for ALMA in
with ALMA Band3 spectral scans this band too.
(Strandet et al., 2016). Acknowledgements
Marcel Popescu1,2 resources for space exploration; and in The survey conducted with the Visible
Javier Licandro 3,4 order to m
itigate the risk of impacts by and Infrared Survey Telescope for Astron-
David Morate 3,4 near-Earth objects. omy (VISTA), the VISTA Hemisphere Sur-
Julia de Len 3,4 vey (VHS1), provides such a survey for
Dan Alin Nedelcu1,2 The physical properties of minor planets minor planets. VHS is the largest survey
are known for just a small fraction of being conducted by the VISTA telescope.
these objects: spectroscopic studies and VHS images the entire southern hemi-
1
Astronomical Institute of the Romanian light curves exist only for several thou- sphere using four filters in the near-
Academy, Bucharest, Romania sand. The results show an unexpected infrared region, namely Y, J, H and Ks
2
IMCCE, Observatoire de Paris, PSL diversity in the composition, density and (McMahon et al., 2013; Cross et al., 2012).
Research University, CNRS, Sorbonne shape of these bodies. The Sloan Digital The band centres of these filters are
Universits, UPMC Univ Paris 06, Sky Survey (SDSS) and Wide-field Infra- located at 1.02, 1.25, 1.65 and 2.15m
Universit de Lille, France red Survey Explorer (WISE) provide infor- respectively. Figure1 shows the trans-
3
Instituto de Astrofsica de Canarias mation for about 100000 minor planets. mission curves of the VISTA filters com-
(IAC), La Laguna, Tenerife, Spain The resulting visible colours and albedos pared to the spectra of two of the most
4
Departamento de Astrofsica, Univer show a greater mixing of the bodies as typical asteroid classes, the primitive
sidad de La Laguna, Tenerife, Spain a function of their orbital parameters, C-type and the rocky S-type. Notice that
which can be explained by the turbulent these four filters allow sampling of some
history of the Solar System (DeMeo et al., of the main spectral features we expect
We have carried out a serendipitous 2015 and references therein). However, for asteroids: the spectral slope and the
search for Solar System objects imaged some of the most important spectral fea- two wide absorption bands at 1and
by the VISTA Hemisphere Survey (VHS) tures used to reveal the compositions of 2m, produced by minerals like olivine
and have identified 230 375 valid detec- minor planets are in the near-infrared and pyroxene.
tions for 39 947 objects. This informa- region. A large survey with observations
tion is available in three catalogues, sampling this spectral region allows us to
entitled MOVIS. The distributions of the refine and complement the global picture Detection of minor planets in VHS
data in colour-colour plots show clusters of these bodies provided by SDSS and
identified with the different taxonomic WISE data. With the aim of characterising the minor
asteroid types. Diagrams that use (YJ) planet population in the VHS, we per-
colour separate the spectral classes formed a serendipitous search within the
more effectively than any other method Figure 1. The normalised throughput profiles of the
observational products of the survey. In
based on colours. In particular, the end- VISTA filter compared with two asteroid spectral order to detect the minor planets, we
class members A-, D-, R-, and V-types types. used the fact that Solar System objects
occupy well-defined regions and can
be easily identified. About 10000 aster- 1
oids were classified taxonomically using S-type
a probabilistic approach. The distribu-
tion of basaltic asteroids across the C-type
Main Belt was characterised using the 0.8
MOVIS colours: 477 V-type candidates Filters
were found, of which 244 are outside
the Vesta dynamical family.
0.6
Arbitrary units
Context
appear as moving sources compared MOVIS-D contains the parameters corre- information to be inferred (Popescu et
with the background stars. This is exem- sponding to all detections; MOVIS-M al., 2016a).
plified in Figure2, using a false-colour contains the magnitudes obtained with
image obtained by combining the stack different filters for each object and The VHS-DR3 release covers ~ 40 % of
of frames observed with J-, Ks- and selected by taking into account the timing the planned survey sky area; thus by the
H-band filters on 5 November 2011 at constraints; and MOVIS-C lists the colours end of the survey the total number of
02:32, 02:42 and 02:52 UT, respectively. which are useful to infer the mineralogy. Solar System objects observed will be at
In this case, the near-Earth asteroid least double these numbers.
(5143) Heracles moved about 2.5 arcsec- The MOVIS catalogues are available
onds between the three consecutive online via the Centre de Donnes
observations and hence appears as three astronomiques de Strasbourg (CDS2) Near-infrared colours of minor planets
separate images compared with the portal. The information provided includes
background stars. observational details, and photometric In order to derive compositional informa-
and astrometric measurements. The tion for minor planets, it is necessary to
Identifying the Solar System objects astrometric positions, corresponding to correlate the spectral behaviour with the
observed in a given field requires cross- 230375 valid detections, were submitted colours. This can be accomplished using
matching of the detected coordinates to the International Astronomical Union the taxonomic classes of asteroid spec-
with those computed at the moment of Minor Planet Center3, and all of them were tral data (since the large majority of the
observation. A dedicated pipeline validated. The observatory site received objects are asteroids). The main goal of
called MOVIS (Moving Objects VISTA the code W91-VHS-VISTA. taxonomies is to identify groups of aster-
Survey) was designed for this task. The oids that have similar surface composi-
first step consists of predicting the posi- The first published catalogues (Popescu tions. The fact that spectra similar to the
tion of Solar System objects potentially et al., 2016a) used the VHS-DR3 data templates proposed by the taxonomic
imaged in each field and retrieving the release, which contains the observations systems were systematically recovered
corresponding detections from the sur- performed between 4 November 2009 by independent authors using diverse
vey products. Secondly, MOVIS removes and 20 October 2013. A total of 39947 data sets and different methodologies
the mis-identifications based on an algo- objects were detected, including 52 provides confidence in these systems.
rithm that takes into account the differ- Near Earth Asteroids (NEAs), 325 Mars
ence between the observed and the Crossers, 515 Hungaria asteroids, The first approach consisted of analysing
computed (OC) positions and also by 38428 Main Belt asteroids, 146 Cybele the observed MOVIS-C colours for the
comparing with the PPXML star cata- asteroids, 147 Hilda asteroids, 270 objects already classified taxonomically.
logue (of positions, proper motions, Two Trojans, 13comets (see example in Fig- There are about 185 objects with spectra
Micron All Sky Survey [2MASS] near- ure 3), 12Kuiper Belt objects and obtained by the Small Main-belt Asteroid
infrared and optical photometry). Finally, Neptune with its four satellites. About Spectroscopic Survey (SMASS) and the
the information is provided in three cata- 10000 objects have accurate spectro- S3OS2 visible spectroscopic survey of
logues for the purpose of organising the photometric data (i.e., magnitude errors 820 asteroids. Within an error of ~ 5 %, the
data for different types of analysis: less than 0.1) allowing compositional main compositional groups are completely
0.5
(2009) compared with
the MOVIS-C data with
c olour errors less than
0.3 0.033 mag. From
Popescu et al. (2016a).
N = 185 N = 1335
0.1
separated (Figure4) using the (YJ) ver- as the end taxonomic type members A-, in the early age of the Solar System. This
sus (JKs) colour-colour plot (Popescu D-, R-, and V-types (Popescu et al., hypothesis challenges the models of the
et al., 2016a). This is the case for S-, C-, 2016a). This survey thus provides an radial extent and the variability of the
A-, D-, V- and C-type asteroids. S-type important tool for investigating the faint early Solar System temperature distribu-
are objects with spectra similar to ordi- asteroids which are hard to observe tion, which generally do not predict melt-
nary chondrite meteorites; C-type spec- spectroscopically. ing temperatures in this region. V-type
tra are similar to carbonaceous chon- asteroids with orbits in the middle and
drites; A-type are olivine-rich asteroids; Based on the available data we were able outer part of the Main Belt are unlikely to
D-type are objects with low albedo and a to classify about 10 000 objects using be scattered Vesta family objects.
featureless red spectrum; V-type are a probabilistic approach which takes into
asteroids with a basaltic composition, the account the errors in the object pho Near-infrared colours allow the easy iden-
most representative one being the aster- tometry and the position of the class in tification of the V-type candidates: aster-
oid (4) Vesta. The X-types present fea- colour space (Popescu et al., 2017). oids with (YJ) > 0.5 and (JKs) > 0.3mag
tureless spectra with a moderate slope A further step is to integrate into this are likely to be members of this class.
and are representative of objects of dif- schema the photometric data obtained Using the more accurate MOVIS-C data
ferent compositions: primitive, like carbo- by SDSS and WISE. (with uncertainties < 0.1mag), and the
naceous chondrites; or metallic, like colour criteria described above, we have
enstatite chondrites. Knowledge of the identified 477 objects, of which 244 of the
albedo is necessary to derive composi- A particular case: the basaltic asteroids V-type candidates are outside the Vesta
tional information of an X-type asteroid. dynamical family (Figure5). This sample
Basaltic asteroids are considered to be almost doubles the number of known
The second approach is to compare the fragments of large bodies whose interiors V-types that are not members of the
distribution of MOVIS-C data in colour- reached the melting temperature of sili- Vesta family (Licandro et al., 2016). In
colour space with the position of colours cate rocks and subsequently differenti- particular we identified 19 V-type aster-
computed for the template spectra of the ated (a core of heavy minerals is formed oids beyond the 3:1 mean motion reso-
different taxonomic classes spanning the with a mantle of lighter minerals, such nance, 13 of them in the middle part of
visible to the near-infrared region (DeMeo as olivine and pyroxene). These asteroids the Main Belt and six in the outer part.
et al., 2009). are classified as V-types and are identi-
fied by their spectrum in the 0.52.5 m
Acknowledgements
In Popescu et al. (2016a) we show that region which shows two deep and sharp
the (YJ) colour is a key parameter for a absorption bands at 0.9 and 2 m. Most The observations were obtained as part of the VISTA
taxonomic classification: those with the of the objects with these characteristics Hemisphere Survey, ESO Programme 179.A-2010
1m band have a large value of (YJ) orbit in the inner part of the Main Belt (PI: R. McMahon). J. de Len acknowledges support
from the IAC. D. Morate acknowledges the Spanish
colour. The colour-colour plots which use and are members of the Vesta collisional MINECO for financial support in the form of a
the Y filter allow separation of the taxo- family, or are likely scattered members of Severo-Ochoa Ph.D. fellowship. J. Licandro, D.
nomic classes much better than has pre- this family. These objects are chunks of M orate, J. de Len, and M. Popescu acknowledge
viously been possible using other col- the crust of the asteroid (4) Vesta, ejected support from the project ESP2013-47816-C4-2-P
(MINECO, Spanish Ministry of Economy and Com-
ours. Even for large photometric errors from it due to a collision. The presence of petitiveness). The work of D. A. Nedelcu, and part
(up to 0.15 mag), the diagrams (YJ) vs basaltic asteroids, unlikely to be scat- of the work of M. Popescu, were supported by a
(YKs) and (YJ) vs (JKs) clearly sepa- tered members of the Vesta family, clearly grant from the Romanian National Authority for
rate the asteroids belonging to the main shows that there were other big differen- Scientific Research UEFISCDI, project number
PN-II-RU-TE-2014-4-2199.
spectroscopic S- and C-complex, as well tiated basaltic asteroids in the Main Belt
Pierre Kervella1,2 Five billion years from now, the Sun will tudes in the visible, L 2 Pup has experi-
Miguel Montargs 3 grow into a red giant star, more than a enced a remarkable, slow photometric
Anita M. S. Richards 4 hundred times larger than its current size. dimming over the last decades by more
Ward Homan 5 It will also experience intense mass loss than 2 magnitudes in the visible. Bedding
Leen Decin 5 in the form of a stellar wind. The end et al. (2002) interpreted this long-term
Eric Lagadec 6 product of its evolution, seven billion dimming as the consequence of the
Stephen T. Ridgway7 years from now, will be a white dwarf star obscuration of the star by circumstellar
Guy Perrin2 about the size of the Earth and ex dust.
Iain McDonald4 tremely dense (density ~ 5 10 6 g cm 3).
Keiichi Ohnaka 8 We observed L 2 Pup on the night of
This metamorphosis will have a dramatic 21March 2013 with NAOS CONICA
impact on the planets of the Solar Sys- (NACO) as part of a survey aimed at
1
Unidad Mixta Internacional Franco- tem, including the Earth. While Mercury imaging the circumstellar environments
Chilena de Astronoma (CNRS UMI and Venus will be engulfed by the giant of selected nearby evolved stars (Kervella
3386), Departamento de Astronoma, star and destroyed, the fate of the Earth et al., 2014a). We used 12 narrow-band
Universidad de Chile, Santiago, Chile is still uncertain. The brightening of the filters spread in wavelength between 1.04
2
LESIA (UMR 8109), Observatoire de Sun will make the Earth hostile to life in and 4.05 m. We processed the image
Paris, PSL Research University, CNRS, about one billion years. As an aside, cubes using a serendipitous imaging
UPMC, Universit Paris-Diderot, France assuming that life appeared on Earth approach (also known as Lucky imag-
3
Institut de Radioastronomie Millimtri 3.7billion years ago (Ohtomo et al., 2014), ing). Using 8400 very short exposures
que, Saint-Martin dHres, France this implies that life on Earth has already (8milliseconds each) in each filter, we
4
Jodrell Bank Centre for Astrophysics, exhausted ~ 80 % of its development were able to freeze the residual atmos-
Dept. of Physics and Astronomy, Uni- time. However, we do not know whether pheric perturbations. After selecting the
versity of Manchester, United Kingdom our then-lifeless rock will be destroyed by best 50 % of the series of images, we
5
Institute of Astronomy, Katholieke the burgeoning Sun, or survive in orbit recentred and averaged them to obtain
Universiteit Leuven, Belgium around the white dwarf. the 12 final, diffraction-limited images.
6
L aboratoire Lagrange (UMR 7293), They were finally deconvolved using a
Universit de Nice-Sophia Antipolis, To address the question of the impact of point spread function (PSF) calibrator
CNRS, Observatoire de la Cte dAzur, the final phases of stellar evolution on star. The morphology of L 2 Pup in these
Nice, France planetary systems, hydrodynamical mod- images (Figure 1) was very surprising.
7
National Optical Astronomy Observa els have been proposed (see, for exam- From a seemingly double source between
tory, Tucson, USA ple, the recent review by Veras, 2016). 1.0 and 1.3 m, the star became a single
8
Instituto de Astronoma, Universidad But observational constraints on the star- source with an east-west extension at
Catlica del Norte, Antofagasta, Chile planet interaction models are still rare. 2.1m, and exhibited a spectacular spiral
Planets of asymptotic giant branch (AGB) loop at 4.0 m!
stars are embedded in complex circum-
The impact of the dramatic terminal stellar envelopes and are vastly outshone We proposed (Kervella et al., 2014a) that
phases of the lives of Sun-like stars on by their parent star. The observation of L 2Pup is surrounded by an equator-on
their orbiting planets is currently uncer- this critical phase of planetary system dust disc. In this framework, the opacity
tain. Observations with NAOS CONICA evolution thus presents considerable, and and thermal emission of the dust change
and SPHERE/ZIMPOL in 20142015 as yet unsolved, technical challenges. As dramatically between 1 and 4 m, provid-
have revealed that the nearby red giant a result, there currently exists only indi- ing a natural explanation for the changing
star L 2 Puppis is surrounded by an rect evidence of the presence of planets aspect of the circumstellar envelope. At
almost edge-on disc of dust and gas. orbiting AGB stars (Wiesemeyer et al., 1m, the dust efficiently scatters the light
We have observed several remarkable 2009). In addition, the masses of AGB from the star, which therefore appears
features in L 2 Pup: plumes, spirals, and stars are notoriously difficult to estimate masked behind the dust band. The dust
a secondary source (L 2 Pup B) which from observations, preventing accurate becomes progressively more transparent
is embedded in the disc at a projected determinations of their evolutionary as the wavelength increases. At 2.2m,
separation of 2 au. ALMA observations states. the thermal emission from the hot inner
have allowed us to measure a mass of rim of the disc is observable through the
0.659 0.043 M for the central star. dust. A colour composite image of
This indicates that L 2 Pup is a close The discovery of the disc of L 2 Puppis L 2Pup in the near infrared is presented
analogue of the future Sun at an age with NACO in Figure2. It shows the intrinsically red
of 10 Gyr. We also estimate the mass of colour of the equatorial dust band due
L 2Pup B to be 12 16 MJup, implying At a distance of only 64 pc (van Leeuwen, to the stronger scattering at shorter
that it is likely a planet or a brown 2007), L 2 Pup is the second nearest wavelengths.
dwarf. L 2Pup therefore offers us a AGB star after R Doradus. In addition to
remarkable preview of the distant future its regular pulsation with a period of Our hypothesis of an edge-on dust disc
of our Solar System. 141days and an amplitude of ~ 2 magni- was initially relatively fragile. But a 3D
N
E
50 mas 5 au
Figure 1. NACO deconvolved images of L 2Puppis elongated, and the subtraction of the Sparks et al. (2008) and Kervella et al.
at a range of wavelengths from 1 to 4m. From
central star revealed the presence of a (2014b).
Kervella et al. (2014a).
second source, L 2 Pup B, at a separation
of 32 milliarcseconds (mas) from the star Apart from the scattered light on the
radiative transfer model using the to the west (Figure 3). discs upper and lower surfaces, a very
RADMC-3D code (Dullemond, 2012) striking signature in the pL map (Figure3,
confirmed that this interpretation of the The polarimetric imaging capability of right panel) comes from the two plumes
NACO images is consistent with the ZIMPOL has been particularly important emerging from the disc. Their high
observations, reproducing convincingly in revealing the structure of the envelope degree of polarisation (~ 30 %) indicates
both the spectral energy distribution and of L 2 Pup (Figure 3, right). As the star that they contain dust and that the scat-
the morphology of the disc (Kervella et is embedded in a dust-rich environment, tering angle is large at ~ 50. These thin
al., 2014a). the scattering of the starlight by the dust plumes, whose transverse diameter is
grains induces a linear polarisation of smaller than 1 au, have a length of more
the photons. For small dust grains, the than 10 au. The large scattering angle
Stunning features from SPHERE polari- degree of linear polarisation pL is a implies that they emerge from the disc
metric imaging smooth function of the scattering angle, close to perpendicular, and propagate in
with a maximum pL value obtained for the northern cone cavity that is otherwise
We took advantage of the Science Verifi- ~ 90 scattering. Knowing the degree of essentially devoid of dust.
cation of the Spectro-Polarimetric High- polarisation therefore allowed us to esti-
contrast Exoplanet REsearch instrument mate the scattering angle over the The map of the degree of polarisation
(SPHERE) to observe L 2 Pup in visible envelope. Knowing and the projected also shows well-defined local maxima at
light imaging polarimetry with the Zurich position of the dust relative to the star in a radius of 6 au, symmetrically east and
IMaging POLarimeter (ZIMPOL) camera the image, then allowed us to retrieve the west of the star. The degree of polarisa-
(Kervella et al., 2015). The observation 3D distribution of the scattering material. tion reached at these positions is very
was carried out on the night of 7 Decem- This polarimetric tomography technique high, up to pL = 60 % in the R-band, cor-
ber 2014. The combination of the high was previously employed, for example, by responding to scattering of the light at
brightness of L 2 Pup and good seeing
resulted in spectacular image quality. The
Strehl ratio produced by the SPHERE
adaptive optics reached more than 40 %
at a wavelength of 646 nm for an atmos-
pheric seeing of ~ 0.7 arcseconds. In one
hour of telescope time, the observation
of L 2Pup and a PSF calibrator star ( Col)
confirmed unambiguously our hypothesis
of an edge-on circumstellar dust disc
(Figure 3, upper left). In addition to reveal-
ing the overall geometry of the dust disc 0.1
as relatively thin, moderately flared Figure 2. Colour com-
posite image of L 2Pup
and extending to at least 13 au the at infrared wavelengths
collected images in the V- and R-bands assembled from NACO
showed remarkable structures in the Jupiter observations. The orbits
Earth Saturn Uranus of four Solar System
envelope of L 2 Pup (Figure 3, upper right).
planets are represented
We detect several spiral arms in the neb- in the lower part of the
ula, as well as two intriguing thin plumes. figure to give the overall
The central source appeared significantly scale of the L 2Pup disc.
V-band p L
Plume 2 Plume 2
Plume 1
Northern cone
Loop Plume 1
Max.
pL
Spiral 1 Segment
Max.
pL
Edge A B
3 au
Band
A B
Max.
pL Max. N
N
Spiral 2 pL
Southern cone E
E
5 au 100 mas 5 au 100 mas
Figure 3. Left: Colour composite intensity image of 0.1 0.2 0.3 0.4 0.5
L 2Pup assembled from SPHERE/ZIMPOL V- and
R-band images. Middle: nomenclature of the
observed structures in the circumstellar environment high brightness of L 2Pup and the high two-thirds the mass of our Sun (0.653
of L 2Pup. Right: degree of linear polarisation, pL, of sensitivity of the array. We detected 0.043 M). It is remarkable that the error
L 2Pup measured with Z IMPOL. The two plumes several molecular emission lines in the budget of this measurement is fully domi-
sketched in the middle panel are also indicated.
selected spectral windows, from 12CO, nated by the uncertainty in the parallax
13
CO, H2O, SO2, 29SiO, SiS and SO. of L 2Pup, as the error from the ALMA
We focus our discussion here on the data fit is only 1.7 %.
29
~ 90. We interpret these maxima as the SiO(=0, J=87) molecular line at a
scattering of the starlight by the inner rim rest frequency of 342.981GHz. The con- The coincidence of the radius where the
of the dust disc, that is, the minimum tinuum subtracted integrated intensity rotation becomes sub-Keplerian and the
radius at which the dust is present with a in this line is presented in Figure 4 (upper radius of the inner rim (maximum of pL,
high density. The existence of an inner left panel). Figure 3) of the dust disc observed with
rim is due to the very high brightness of ZIMPOL indicates that the rotation of the
the central star (2000 times Solar lumi- Our analysis is based on the position- gas becomes sub-Keplerian precisely
nosity), which would lead to the sublima- velocity diagram (PVD) formalism. The when it enters the dust disc. This very
tion of any dust grains closer to the star PVD is computed by integrating the interesting effect is likely due to the vis-
(Homan et al., 2017). ALMA spectro-imaging data cube over cous coupling of the gas and dust within
a 0.02arcsecond wide pseudo-slit the disc. The dust is sensitive to the
aligned with the disc plane (east-west strong radiative pressure from the central
An analogue of the future Sun, 5 billion direction). The resulting diagram (Figure star, and is thus subject to a reduced
years from now 4, lower left) shows the velocity of the effective gravity resulting in a slower
molecular gas as a function of the posi- orbital velocity than the gas. As the inter-
L 2 Puppis was observed with the tion along the slit. Thanks to the excellent nal cavity within 5 au contains very little
Atacama Large Millimeter/submillimeter signal-to-noise ratio of the ALMA data, dust, the gas rotates freely there. But
Array (ALMA) in Cycle 3 in Band 7 we can measure very accurately the when it reaches the inner rim of the dust
(340GHz, wavelength ~ 0.8 mm) using orbital motion of the gas in the disc disc, it is slowed down by friction with
the longest available configuration of the plane, and more precisely the maximum the dust, which explains its sub-Keplerian
interferometer with baseline lengths of up velocity of the gas as a function of the rotation.
to 16km (Kervella et al., 2016). This con- separation from the centre of rotation. We
figuration provided the highest possible determined that this maximum velocity From the measured mass of L 2 Pup,
angular resolution currently achievable by profile closely follows Keplers law up to a stellar evolution models predict that its
ALMA, with a beam size of only 15mas. radius of 56 au from the star. Figure 4 age is ~ 10Gyr. The mass, radius and
It is interesting to remark that this resolu- (lower left and right panels) clearly shows pulsation period are all consistent with
tion matches very well that of SPHERE/ the two rotation regimes: Keplerian within a main sequence mass identical to that
ZIMPOL in the visible (1620mas). We the inner 5 au (that is, v ~ R 1/2), and sub- of the Sun. The missing third of a solar
selected velocity resolutions of 100 to Keplerian beyond 6 au (v ~ R 0.85). A mass has been lost by L 2 Pup during its
400ms 1 for the molecular line spectral smooth transition is observed between 5 evolution. The extraordinary coincidence
windows, corresponding to a spectral and 6 au. From the Keplerian motion of of having a Sun-like AGB star in the close
resolution of R ~ 1000000. This power- the inner 5 au, we could determine with vicinity of the Sun thus provides us with
ful combination of very high spatial and very high accuracy ( 6.6 %) the present a privileged preview of the very distant
spectral resolution is permitted by the mass of the AGB star, finding that it is future of our own star.
10
Velocity 33.0 (km s 1 )
15
Velocity (km s 1 )
0 10
10
5
Photosphere
Inner rim
20 Companion (ALMA)
M sin i = 0.653 0.011 M
V R with = 0.85 0.06
East inflection
5 0 5 10 15 20 West inflection
30
0.3 0.2 0.1 0.0 0.1 0.2 0.3 0.5 1 2 5 10 20
Position offset on sky (arcseconds) Radius (au)
A candidate planet orbiting in the disc of We estimated the mass of the companion convert this offset into a mass of 12
L 2 Pup by comparing the position of the centre 16MJup for this companion, which corre-
of rotation of the molecular disc and the sponds to a planet or a low mass brown
The ALMA data in the continuum showed position of the continuum emission peak. dwarf.
the presence of an excess of emission The centre of rotation of the molecular
in the western wing of the disc (Figure 5), disc is very well defined from the ALMA We also detected excess emission in the
contributing 1.3 % of the central stars PVD (Figure 4), and it corresponds to the PVD of the molecular lines (=0,
flux. This emission coincides almost centre of gravity of the mass enclosed by J=32) of 12CO and 13CO at the location
perfectly with the secondary source the disc. The continuum emission peak of the candidate planet, at a velocity of
L 2PupB detected with SPHERE/ZIMPOL provides the position of the AGB star. We 12km s 1 (Figure 6). We propose that this
one year before the ALMA observations. determined that the two points are coin- emission comes from the extended
This continuum emission could be pro- cident within 0.55 0.75 mas. As we molecular envelope accreted by L 2PupB
duced by a dusty envelope or by an know the mass of the central star and the from the wind of the AGB star. This
accretion disc surrounding L 2 Pup B. current separation of L 2 Pup B, we can measured velocity is consistent with the
12
CO( = 0, J = 32) 13
CO( = 0, J = 32)
Companion (SPHERE)
Inner rim
30 5
5 1 5 10 Companion (ALMA)
30 0 5
Photosphere
25 M sin i = 0.653 M 25
20 20 Figure 6. Emission of
L 2PupB in two CO
molecular isotopologue
Velocity (km s 1)
Velocity (km s 1)
v v0
B (ALMA, 2015.84)
The forthcoming Extremely Large Tele-
A
scope (ELT) will provide an angular reso-
lution of 60 mas at 10 m, 12 mas at
B (ZIMPOL, 2014.93) 2.2m and 3 mas in the visible. Observ-
ing L 2 Pup with the ELT will be easy: it
is very bright (mV~7.5, mK~ 2), and
thus provides an excellent natural guide
star for adaptive optics wavefront sens-
Transition
A
References
B
Bedding, T. R. et al. 2002, MNRAS, 337, 79
Dullemond, C. P. 2012, Astrophysics Source Code
Library, 1202.015
Eisenhauer, F. et al. 2011, The Messenger, 143, 16
Homan, W. et al. 2017, A&A, submitted
Prospects for future observations determine its mass from its Keplerian Kervella, P. et al. 2014a, A&A, 564, A88
velocity amplitude. Kervella, P. et al. 2014b, A&A, 572, A7
The longest ALMA baselines of 16km Kervella, P. et al. 2015, A&A, 578, A77
combined with the shortest wavelengths Optical interferometry with the Very Large Kervella, P. et al. 2016, A&A, 596, A92
Khouri, T. et al. 2016, A&A, 591, A70
(Bands 9 and 10) will soon give access Telescope Interferometer (VLTI) commis- Lopez, B. et al. 2014, The Messenger, 157, 5
to an angular resolution ~ 6 mas. Assum- sioning instrument VINCI has been used Millour, F. et al. 2016, Proc. SPIE, 9907, 99073
ing a mass of 12 MJup for L 2 Pup B, its by Kervella et al. (2014a) to measure the Ohnaka, K., Weigelt, G. & Hofmann, K.-H. 2016,
Roche lobe has a diameter of about angular diameter of the central AGB star A&A, 589, A91
Ohtomo, Y. et al. 2014, Nature Geoscience, 7, 25
0.6au, or 10mas. This means that it will of L 2 Pup. The VLTI second-generation Sparks, W. B. et al. 2008, AJ, 135, 605
be possible to resolve the putative accre- instruments GRAVITY (Eisenhauer et al., van Leeuwen, F. 2007, A&A, 474, 653
tion disc around L 2 Pup B (particularly 2011) and the Multi AperTure mid-Infrared Veras, D. 2016, Royal Society Open Science, 3, 150571
in CO molecular emission) and directly SpectroScopic Experiment (MATISSE: Wiesemeyer, H. et al. 2009, A&A, 498, 801
Supernova 1987A at 30
Jason Spyromilio1 ranged across astroparticles and all made famous by HST, Chandra and
Bruno Leibundgut1 wavelengths of the electromagnetic ATCA images (see Figure 1, left), is readily
Claes Fransson2 spectrum, then one might consider one visible in images from NAOS-CONICA
Josefin Larsson2 had found the perfect source. (NACO), and the Spectrograph for INtegral
Katia Migotto2 Field Observations in the Near-Infrared
Julien Girard1 SN1987A is just such a heavenly object! (SINFONI) as well (Larsson et al., 2016).
That it is circumpolar for the more south- Figure 1 right shows a very recent NACO
ern astronomical sites adds to its opti- image at 2.15 m (Ks-band). The flux in
1
ESO mality. Located in the Large Magellanic the Ks-band is dominated by Brackett-
2
Department of Astronomy, The Oskar Cloud (LMC), it is near enough to be emission at 2.165m illuminated from the
Klein Centre, Stockholm University, resolved, yet far enough to not be a outside. The illumination of the ring at
Sweden threat, along an almost unextinguished the earliest times, by the ultraviolet (UV)
line of sight, in a relatively uncluttered light emerging as the shock broke the
part of its host galaxy. It is evolving on surface of the progenitor star, was used
Thirty years on, SN 1987A continues to a human timescale. Many articles on to determine a geometric distance to the
develop and, over the last decade in 1987A have appeared in the pages of LMC and remains one of the anchors of
particular, has: revealed the presence of The Messenger over the years and there- the extra-galactic distance ladder. The
a large centrally concentrated reservoir fore we will not dwell here on the past ring illumination also provided the first
of dust; shown the presence of molecu- but rather focus on the current state and evidence of the radiation from the shock
lar species within the ejecta; expanded ponder an exciting future. A comprehen- break-out, lasting only a few minutes but
such that the ejecta structure is angu- sive review (McCray & Fransson, 2016) with a temperature of about a million
larly resolved; begun the destruction of appeared recently and covers SN1987A degrees.
the circumstellar ring and transitioned over the past 10000 days.
to being dominated by energy sources Later, when the fastest ejecta, moving
external to the ejecta. We are partici- Despite fading by seven orders of magni- at ~10 % of the speed of light, reached
pating in a live experiment in the creation tude from its peak, the supernova and its the ring, the shocked gas emitted brightly
of a supernova remnant and here the surroundings remain readily observable. at wavelengths from radio to X-ray.
recent progress is briefly overviewed. Lengthy exposure times are still necessary Recently, observations from HST have
Exciting developments can be expected to study the details and, critically, the time- been used to show that the ring is begin-
as the ejecta and the reverse shock scales over which the supernova changes ning to suffer from the effects of the ejecta
continue their interaction, the X-rays remain of order half a year (approximately colliding into it (Fransson et al., 2015). It
penetrate into the cold molecular core the light travel time of the ejecta at this will take a while, but the ring is currently
and we observe the return of the mate- epoch); therefore continued vigilance is being destroyed. A simple extrapolation
rial into the interstellar medium. We needed. ESO, together with the Hubble estimates this process will be complete by
anticipate that the nature of the remnant Space Telescope (HST) and the Australia ~ 2025. However, new spots of emission
of the leptonisation event in the centre Telescope Compact Array (ATCA), are the outside the ring have appeared and con-
will also be revealed. sole observatories that, thanks to the evo- tinued observations may yet provide sur-
lution of their observing capabilities, have prises about the surrounding structure.
provided the necessary continuous ultra- We get to watch in real time as a shock
In the preface to the first SN1987A con- violet/optical/near-infrared/radio coverage wave with well-defined characteristics
ference thirty years ago (Danziger, 1987), of the supernova, and fortunately the fire- impinges on a well-understood structure
Lodewijk Woltjer, then Director General of works are still continuing. Together with (both in density and composition); a text
ESO, welcomed the participants with the similar monitoring by the Chandra and book illustration of shock theory.
prescient statement It is very well possi- X-ray Multi-Mirror Mission (XMM-Newton)
ble that [] SN1987A will remain observ- space telescopes in X-rays, these facili-
able for thousands of years to come. ties have provided a nearly complete Radioactivities
multi-wavelength coverage of the devel-
opment of the supernova. These tele- Inside the ejecta, radioactive species
Introduction scopes are providing a legacy dataset for freshly synthesised in the explosion pro-
this object that cannot be repeated. vide gamma rays and energetic positrons
If an observational astronomer was that deposit their energy into the ejecta,
allowed to pick the parameters of the The progenitor star (Sanduleak 69202) provided they do not escape. Which iso-
object of study, then ideally the angular of SN1987A cleared a volume around topes are present, and how much of
size would be matched to the resolution itself, sweeping-up material blown off in each, are critical to our understanding of
of the telescope, the dimensions of the earlier evolutionary stages (about the emerging spectrum. The isotope mix
physical processes would be matched 8000years ago) into an hour-glass struc- also places limits on the mass cut (the
to the angular size and the variability ture dominated by an equatorial ring. This mass coordinate in the proto-neutron star
matched to the proposal cycles for tele- structure, first observed with the New where the ejection starts and the collapse
scope time. If, in addition, the physics Technology Telescope (NTT) in 1989, and ends) and provides a measure of the
nucleosynthetic yield of the supernova. ARray (NuSTAR) detection (Boggs et al., core. This distribution is one of the main
The presence of 56Ni (source of 56Fe) had 2015) and the INTErnational Gamma-Ray diagnostics of the explosion dynamics
long been confirmed in SN1987A, as Astrophysics Laboratory (INTEGRAL) during the first seconds.
had 57Co. Theory predicted that 44Ti detection by Grebenev et al. (2012) of
should also be made in the explosion of hard X-ray lines from 44Ti. Observations
supernovae. Combining Very Large Tele- with SINFONI (Kjaer et al., 2010; Larsson Shocks
scope (VLT) and HST spectra with time- et al., 2016) and HST (Larsson et al.,
dependent non-local thermodynamic 2011) have revealed a complex structure While the forward shock moves through
equilibrium (LTE) radiative transfer calcu- of emission from atomic species that, in the ring, slowing down the ejecta and
lations, it was determined that 44Ti had some cases, are collocated with the radi- accelerating the ring material, the reverse
taken the role of key energy supplier to oactive species and in others are illumi- shock is formed by the supernova ejecta
the supernova eight years after the explo- nated by external sources. In particular, hitting the decelerated medium behind
sion (Jerkstrand et al., 2011). the SINFONI observation of the 1.644m the forward shock. The reverse shock is
[SiI]+[FeII] line gives a three-dimen- formed in successfully slower and denser
It was consequently exciting to see both sional view of the 44Ti distribution in the regions in the supernova ejecta.
the Nuclear Spectroscopic Telescope ejecta, responsible for powering the inner
The supernova ejecta are being exposed
from the outside to X-rays from the ring
120 Figure 2. The light interaction and at some point during the
curve of the super-
supernovas teenage years the dominant
nova over the past
5000 days. Different source of energy became the conversion
100 components and of kinetic energy from the supernova
wavelengths are iden- ejecta with the surroundings. Quite ele-
tified. The dimming of
gantly, just as the radioactive elements
80 the ring in optical
whose decay had powered the emission
Flux (10 13 erg s 1)
X
Z
however, continues out into the circum- ring have also been found. The neutron the sites. They have all contributed through their
expertise and enthusiasm to generating this beautiful
stellar medium beyond the ring, and will star has so far defied detection.
and unique data set. We also want to thank the time
hopefully reveal more of the several solar allocation committees over the decades who have
masses of material thought to have been There have indeed also been great sur- recognised the uniqueness of the supernova and
lost by the progenitor star. The mass of prises. Tracing the explosion mechanism have supported this research.
the ring is only ~ 0.06 M. The X-ray by directly observing the geometry of the
The authors thank the current editor, himself a
emission is expected to decay more element distribution in the inner ejecta naked eye observer of SN 1987A, for improving
slowly than the optical ring emission. It confirms the non-spherical explosion the article and wish the next editor a Galactic
will therefore continue to illuminate more models. The illumination of the inner supernova for herself.
and more of the ejecta, and thus also ejecta by X-rays from the ring is a new
give a new view of the abundance and feature in the development of SN1987A. References
hydrodynamic structure of the ejecta. The It provides a novel and unexpected win-
supernova will then gradually transform dow on parts of the ejecta that have so Boggs, S. E. et al. 2015, Science, 348, 670
Culhane, M. & McCray, R. 1995, ApJ, 455, 335
into a supernova remnant similar to other far been unobservable. The molecules in
Danziger, I. J. 1987, Proc. ESO Workshop on
young remnants. We can follow this in the inner ejecta were predicted early on SN1987, ESO, Garching
real time for hundreds of years, perhaps and have finally been found. ALMA, with Frank, K. A. et al. 2016, ApJ, 829, 40
longer, as suggested by Lo Woltjer. In all its first observations, together with Fransson, C. & Chevalier, R. A. 1987, ApJ, 322, 15
Fransson, C. et al. 2007, The Messenger, 127, 44
these aspects ESO can continue to play Spitzer and Herschel, have told us more
Fransson, C. et al. 2015, ApJ, 806, L19
a leading role. about the dust in SN1987A than we Fransson, C. et al. 2016, ApJ, 821, 5
could have guessed two decades ago. Grebenev, S. A. et al. 2012, Nature, 490, 373
Ten years ago we were already musing The reverse shock has been firmly Indebetouw, R. et al. 2014, ApJ, 782, L2
Jerkstrand, A. et al. 2011, A&A, 530, A45
about the future development of SN1987A observed and adds another important
Kamenetzky, J. et al. 2013, ApJL, 773, L34
(Fransson et al., 2007). We predicted aspect to the evolution of the supernova. Kjaer, K. et al. 2010, A&A, 517, 51
exciting events the destruction of the Lakievi, M. et al. 2012, A&A, 541, L1
inner ring and the illumination of material Larsson, J. et al. 2011, Nature, 474, 484
Larsson, J. et al. 2016, ApJ, 833, 147
outside the ring. We were also hoping
Matsuura, M. et al. 2011, Science, 333, 6047
to find the compact remnant inside Acknowledgements
Matsuura, M. et al. 2015, ApJ, 800, 50
SN1987A and hopefully other surprises. It is a pleasure to thank all the staff at the various
McCray, R. & Fransson, C. 2016, ARAA, 54, 19
The ring has started to fade, indicating observatories and in particular those involved in the
Orlando, S. et al. 2015, ApJ, 810, 168
Potter, T. M. et al. 2009, ApJ, 705, 261
that it will be destroyed in the near future, Paranal and ALMA operations, both in preparing the
Zanardo, G. et al. 2014, ApJ, 796, 82
and the first traces of material beyond the observations in Garching and in executing them on
Ross McLure1 mately the same as it was less than a varying degrees of hard evidence and
Laura Pentericci2 billion years after the Big Bang (i.e. z ~ 7), speculation, active galactic nuclei (AGN)
and that in the intervening period the Uni- feedback, stellar winds, merging and
and the VANDELS team verse was forming stars about ten times environmental-/mass-driven quenching
more rapidly. However, despite this it is have all been widely discussed in the
still perfectly plausible to argue that the literature (see Fabian, 2012 and Conselice,
1
Institute for Astronomy, University peak in cosmic star formation history 2014 for reviews). It seems clear that
of Edinburgh, Royal Observatory occurred anywhere in the redshift interval quenching must be connected to the
Edinburgh, United Kingdom 1.5<z<3.5, an uncertainty of two and interplay between gas outflow, the inflow
2
INAF, Osservatorio Astronomico di a half billion years. Moreover, the results of pristine gas, the build-up of the
Roma, Monteporzio, Italy of the latest generation of semi-analytic mass-metallicity relation and morpho
and hydro-dynamical galaxy simulations logical transformation. However, to date,
(for example Somerville & Dav, 2015) the relative importance of, and intercon-
VANDELS is a new ESO spectroscopic demonstrate that, from a theoretical per- nections between, the different underly-
Public Survey targeting the high-redshift spective, even reproducing the evolution ing physical mechanisms remain unclear.
Universe. Exploiting the red sensitivity of the cosmic star formation density can
of the refurbished VIMOS spectrograph, be problematic. Within this context, a series of spectro-
the survey is obtaining ultra-deep opti- scopic campaigns with the Very Large
cal spectroscopy of around 2100 galax- Over the last decade it has become Telescope (VLT) and the VIsible Multi
ies in the redshift interval 1.0 < z < 7.0, clear that the majority of cosmic star for- Object Spectrograph (VIMOS), such as
with 85 % of its targets selected to mation is produced by galaxies lying on the VIMOS Very Deep Survey (VVDS;
be at z 3. The fundamental aim of the the so-called main sequence of star for- LeFvre et al., 2005), the COSMOS
survey is to provide the high signal- mation (Noeske et al., 2007). The main spectroscopic survey (zCOSMOS; Lilly
to-noise spectra necessary to measure sequence is a roughly linear relationship et al., 2007) and the VIMOS Ultra Deep
key physical properties such as stellar between star formation rate (SFR) and Survey (VUDS; Le Fvre et al., 2015),
population ages, metallicities and out- stellar mass, the normalisation of which have played a key role in improving our
flow velocities from detailed absorption- increases with lookback time. Galaxies understanding of galaxy evolution, pri-
line studies. By targeting two extraga- lying well above the main sequence can marily through providing large numbers
lactic survey fields with superb multi- be considered to be starbursts, while of spectroscopic redshifts over wide
wavelength imaging data, V ANDELS those falling well below the main sequence fields. The VANDELS survey is designed
will produce a unique legacy dataset for are passive, or quenched. to complement and extend the work of
exploring the physics underpinning these previous campaigns by focusing on
high-redshift galaxy evolution. The evolution in the normalisation of ultra-long exposures of a relatively small
the main sequence over the last 10Gyr number of galaxies, pre-selected to lie
is now relatively well established, with at high redshift using the best available
Background the average SFR at a given stellar mass photometric redshift information.
increasing by a factor of about 30
Understanding the formation and evolu- between the local Universe and redshift
tion of galaxies, from the collapse of z=2 (for example, Daddi et al., 2009). The survey
the first gas clouds at early times to the However, at higher redshifts the evolution
assembly of the detailed structure we of the main sequence is still uncertain, The VANDELS (Proposal ID 194.A-2003)
observe in the local Universe, remains the despite a clear theoretical prediction that survey is repeatedly targeting a total of
key goal of extragalactic astronomy. it should mirror the increase in halo gas eight overlapping VIMOS pointings (see
Despite the immense challenge, the last accretion rates (for example, Dekel et al., Figure 1), four in the United Kingdom
15 years have been a period of unprece- 2009). Depending on their assumptions InfraRed Telescope (UKIRT) Infrared
dented progress in our understanding of regarding star formation histories, metal- Deep Sky Survey (UKIDSS) Ultra Deep
the basic demographics of high-redshift licity, dust and nebular emission, different Survey (UDS) and four in the Chandra
galaxies. Indeed, thanks largely to the studies find that at a given stellar mass Deep Field South (CDFS). VANDELS
profusion of deep, multi-wavelength sur- the increase in average SFR between observations are exclusively performed
vey fields, we now have a good working z=2 and z=6 is anything from a factor using the medium resolution (MR) grism
knowledge of how the galaxy luminosity of about two (for example, Gonzlez et al., + GG475 order-sorting filter, which pro-
function, stellar mass function and global 2014), to a factor of about 25 (for exam- vides medium resolution (R~700) spectra
star formation rate density evolve with ple, de Barros et al., 2014). covering the wavelength range 4800
redshift (see Madau & Dickinson, 2014 for 10000 at a dispersion of 2.5 pixel 1.
a recent review). Moreover, although the decline in the
global star formation rate density over the Each of the eight pointings is observed
As a consequence, we can now be last 10 Gyr has been well characterised, four times, each pass receiving 20 hours
confident that the star formation rate the primary physical drivers responsible of on-source integration. Using a nested
density we observe locally is approxi- for this quenching remain uncertain. With slit allocation strategy, targets are allocated
galaxies.
G-band
Ca II H
Ca II K
is also targeting small samples of rarer
Mg II
Mg I
Mg I
Fe II
Fe II
Fe I
H
bright systems such as AGN and galaxies
3.0
detected by the Herschel satellite.
He II
Mg I
Zn II
C IV
Fe II
Fe II
Fe II
Fe II
continuum SNR of about 3 per resolution
C III
Ni II
N iII
A III
A III
C IV
N IV
Fe II
A III
Ly
Si II
Si II
C II
OI
1.5
parameters via absorption line studies,
He II
Si IV
Si IV
C IV
Fe II
C III
Ni II
A III
A III
Ly
Si II
Si II
C II
OI
0.5
0.0
1200 1300 1400 1500 1600 1700 1800 1900 2000
Rest-frame wavelength ()
and will therefore have an impact on slopes) will also lead to significantly stand the impact of galactic outflows
many areas of high-redshift galaxy evo improved estimates of stellar masses on star formation at z 2. Measuring
lution science. However, the original and SFRs. Importantly, this means that the balance of inflow, outflow and star
VANDELS survey proposal was motivated the V ANDELS dataset will allow the formation will enable models of the
by a small number of key science goals, stellar mass stellar metallicity relation evolving gas reservoir to be tested and
three of which we briefly discuss below. to be studied out to z ~ 5 for the first address the origins of the Fundamental
time. Moreover, the improved stellar Metallicity Relation (Mannucci et al.,
1. Stellar metallicity and dust attenuation mass and SFR estimates for about 2010). Finally, comparing the outflow
Tracing the evolution of metallicity is 1800 spectroscopically confirmed star- velocities of star-forming galaxies with
a powerful method of constraining forming galaxies at 2.4 < z < 7.0 will and without hidden AGN (as identified
high-redshift galaxy evolution via its also allow accurate calibration of photo- from X-ray emission) will allow the role
direct link to past star formation and metric determinations of the evolving of AGN feedback in quenching star
sensitivity to interaction (inflow/outflow) stellar mass and SFR functions. formation and the build-up of the red
with the intergalactic medium. Moreo- sequence to be investigated.
ver, accurate knowledge of metallicity 2. Outflows
is essential for deriving accurate star Along with stellar metallicity measure- 3. M
assive galaxy assembly and
formation rates and breaking the ments, a key science goal for V ANDELS quenching
degeneracy between age and dust is the study of outflowing interstellar A key sub-component of VANDELS
extinction (for example, Rogers et al., gas. It is now becoming increasingly is obtaining deep spectroscopy of
2014). clear that high-velocity outflows may ~ 300 massive, passive galaxies at
be ubiquitous amongst star forming 1.0<z<2.5. This population holds the
Recent studies using stacked spectra galaxies at z > 1, with mass outflow key to understanding the quenching
of relatively small samples (for example, rates comparable to the rates of star mechanisms responsible for producing
Steidel et al., 2016) have shown that formation (for example, Bradshaw et al., the strong colour bi-modality observed
it is possible to derive accurate stellar 2013). Such outflows may be playing at z < 1, together with the significant
metallicities from the rest-frame UV a major role in the termination of star evolution in the number density, mor-
spectra of galaxies at z 2, provided formation at high redshift and the phology and size of passive galaxies
the spectra have a high enough SNR. build-up of the massmetallicity rela- observed between z = 2 and the pre-
The VANDELS data will allow metal tion. sent day. For the majority of the pas-
licities to be measured for hundreds sive sub-sample, the VANDELS spec-
of galaxies at 2.4<z<5.5, both indi- Crucially, the high-SNR, medium- tra will provide a combination of crucial
vidually and via stacking (see Figures2 resolution, VANDELS spectra will allow rest-frame UV absorption-line informa-
and 3) and therefore offers the pros- accurate measurements of outflowing tion and Balmer break measurements.
pect of transforming our understanding interstellar medium velocities from Combined with the unrivalled photo-
of metallicity at high redshift. high- and low-ionisation UV interstellar metric data available in the UDS and
absorption features (for example, CDFS fields, it will be possible to break
It is worth noting that the ability to inde- Shapley et al., 2003). The fundamental age/dust/metallicity degeneracies and
pendently constrain the stellar metallic- goal is to measure the outflow rate as deliver accurate stellar mass, dynami-
ity and dust attenuation (from the ratio a function of stellar mass, SFR, and cal mass, star formation rate, metal
of observed to intrinsic UV spectral galaxy morphology, in order to under- licity and age measurements via full
Report on the
Alain Smette1
Florian Kerber1
Andreas Kaufer1
1
ESO
quality of the data; (ii) an invited talk, or cute novel and innovative self-contained sure time calculator (ETC) callable by a
several, on the specific theme of the ses- calibration methods and concepts. A user script, which can also be used to
sion; and (iii) contributed talks on various specific session was organised to pre- systematically compare observations
calibration or data reduction aspects. sent their content and merit to all partici- with expectations and to analyse hard-
Ample time was left after each presenta- pants at the workshop. These calibration ware problems. Furthermore, how
tion, and at the end of each session, for proposals will then be executed during could an ETC be used for calibration
lively discussion. pre-allocated time in due course. potentially reducing the number and
frequency of on-sky calibrations
The themes of the various sessions were All the presentations, recordings and and how best to follow up on this
focused: on calibration of adaptive- question-and-answer sessions will soon approach when comparing the model
optics-fed instruments (SPHERE); infrared be available on Zenodo1 or through the with reality?
spectroscopy and metrology; high- workshop webpage2. 4. P resentations by Miwa Goto on infra-
accuracy wavelength calibration (such as red spectroscopy and Florian Kerber
for HARPS, ESPRESSO, and the Giant on the Low Humidity ATmospheric
Magellan Telescope [GMT] Consortium The retreat PROfiling radiometer (LHATPRO:
Large Earth Finder [G-CLEF]); reference Kerber et al., 2012) indicated that the
data (molecular line parameters and After the workshop, a small group of ESO VLT could fly when certain conditions
atomic lines used for wavelength calibra- participants met at Paranal for a retreat. occur: the amount of precipitable
tion); lessons learned from past instru- They identified the following potentially water vapour above Paranal can occa-
ments regarding polarimetry; calibrations game-changing topics or actions for the sionally be the same as on a site at
for integral field units and sky background operation of the La Silla Paranal Observa- 5000 metres (Kerber et al., 2014)! On
reduction strategies in multi-fibre spectro- tory, which were then ordered on a 2D the other hand, the number of pro-
graphs; photometry; astrometry; the graph of scale of impact vs likelihood grammes requesting the best seeing
Earths atmosphere; wide-field surveys, of execution: conditions is small. If the opportunities
as obtained by VISTAs infrared camera 1. The integration of the high-accuracy are rare, how could the Observatory
VIRCAM or the future LSST; and data astrometric and photometric data, best make use of them? ESO should
reduction. obtained by Gaia, LSST and surveys promote programmes whose science
like the VISTA Hemisphere Survey can only be carried out under excellent
The concluding remarks by Susanne (VHS), into ESO operations was recog- conditions. The Call for Proposals for
Ramsay (ESO) crystallised various nised by all as the most likely to hap- Period 100 will already mention this
themes which often appeared in the vari- pen with the largest impact. Aspects concept, which could be reinforced in
ous presentations. For example, is cali- that will be impacted range from the future calls once the implications are
bration a tool to fix hardware issues: calibration of the telescope adaptors, better evaluated.
can that step be avoided by improving the internal astrometric calibration of 5. Should the calibration strategy be
instrument design? Can we rely on physi- instruments like KMOS, to data reduc- better matched to the requested sci-
cal instrument models instead? However, tion, on the basis that most fields will ence? At one extreme, we could imag-
since everything changes, one must be have a sufficiently high density of stars ine that users provide not only their
always attentive and constantly assess for accurate astrometric and photo- science Observing Blocks, but also all
the quality of calibrations and their valid- metric calibrations. their Calibration Blocks. The content
ity period (semper vigilo): calibration plans 2. A nother potentially high-impact topic of such Calibration Blocks would also
are living things. But this task should not is how to better characterise the state be based on an ETC to ensure that
keep us from being more ambitious, for of the atmosphere and, based on that, the quality of the science data is not
example in attempting to reduce the time how to forecast relevant atmospheric degraded, for example due to insuffi-
spent on sky-subtraction in the near parameters, along with which data cient signal-to-noise ratio in the flat
infrared. Interaction with users is also a should be used for optimal processing fields.
key input: data that cannot be reduced of adaptive optics data reduction and 6. Instrument Operations Teams ensure
do not return any science! Finally, ESO analysis? An accurate atmospheric that instruments provide the best
should prepare now and respond to the profile is also required for optimal cor- science and calibration data. They
challenges to be presented by LSST and rection of telluric absorption lines by should, however, be encouraged to
the European Space Agency (ESA) Gaia tools such as Molecfit (Smette et al., contact expert users in the community
satellite, and for the new instrumentation 2015; Kausch et al., 2015). What will be to promote collaboration with ESO
on the 40-metre-class Extremely Large the impact of high-accuracy forecasts and disseminate the knowledge to the
Telescope. (in particular, of the turbulence includ- wider community, or to identify specific
ing the seeing) on observations within problems with an instrument.
An innovative feature of the meeting was a time frame of hours to days? 7. Does the ELT have specific calibration
that technical time on the VLT (and on the 3. P hysical modelling of the instrument requirements which can only be
ESO 3.6-metre) was pre-allocated in behaviour was best illustrated by the addressed by specific VLT observa-
preparation for the calibration workshop. talk by Robert Lupton on LSST. Ideas tions? The next few years should be
This observing time will be used to exe- that were identified included an expo- used to first identify these needs and
then define and conduct the relevant The participants in the retreat compiled operations were identified and need to be
observations. and agreed on a list of action items to brought to fruition. We encourage every-
8. N ew calibration sources such as further explore these different topics and one interested in the subject to further
Laser Frequency Combs or stable transform them into specific improve- explore these topics with us through the
Fabry-Prot calibration units will soon ments for their integration into ESO oper- email account calibration2017@eso.org.
become operational at ESO: what is ations. These action items and the corre-
their potential for other VLT instru- sponding deadlines will be pursued in
ments? Problems with high-purity order to ensure progress towards a timely References
Thorium-Argon hollow-cathode lamps implementation. Kaufer, A. & Kerber, F. (eds.) 2007, Proc. ESO
following recent stricter environmental Instrument Calibration Workshop, ESO Astro
regulations could be dealt with by a physics Symposia, Springer
bulk order in collaboration with other Conclusions Kausch, W. et al. 2015, A&A, 576, 78
Kerber, F. et al. 2012, The Messenger, 148, 9
observatories. Kerber, F. et al. 2014, The Messenger, 155, 17
9. ESO should take a more active role in According to the feedback received, the Smette, A. et al. 2015, A&A, 576, 77
defining the needs for laboratory data. 2017 ESO Calibration Workshop
Archival data may play a crucial role succeeded in its aim of encouraging dis-
Links
to improve molecular line parameters cussion of calibration issues, not only for
which are required for accurate, syn- ESO instruments but also at other ground- 1
enodo: http://www.zenodo.org
Z
thetic telluric line correction in tools based observatories. Seeds of potential 2
C onference web page: http://www.eso.org/sci/
such as Molecfit. game changers in improving ESO future meetings/2017/calibration2017.html
DOI: doi.org/10.18727/0722-6691/5008
Highlights from the CERN/ESO/NordForsk
Francesca Primas1 solid networks. The event was very well the GENERA activities very closely. The
Genevive Guinot 2 attended and was declared a success. first meeting of the project was held at
Lotta Strandberg 3 The main highlights of the meeting are ESOs Headquarters in June 2015. The
reported. final goal of GENERA is very ambitious,
i.e., to propose and create organisational
1
ESO structures allowing physics research in
2
CERN, European Organization for GENERA and its objectives Europe to benefit from a more gender-
Nuclear Research, Geneva, Switzerland balanced research community.
3
NordForsk, Oslo, Sweden The Gender Equality Network in the
European Research Area (GENERA) is a Within the GENERA network, one
Horizon 2020 project that focuses on special initiative that looks in more detail
In their role as observers on the EU evaluating, monitoring and improving at national gender equality plans and
Gender Equality Network in the existing or new gender equality plans of at the existence of innovative activities
European Research Area (GENERA) research organisations in the field of that help with the gender balance, is
project, funded under the Horizon 2020 physics. The GENERA Consortium the organisation of national Gender in
framework, CERN, ESO and NordForsk includes 13 beneficiary partners, either Physics Day (GiPD) events. Each of the
joined forces and organised a Gender Research Performing Organisations 13 beneficiary partners is expected to
in Physics Day at the CERN Globe of (RPOs) or Research Funding Organisa- organise one such event in their own
Science and Innovation. The one-day tions (RFOs) scattered across Europe, country. Each event follows common
conference aimed to examine innovative and a number of associate partners organisational guidelines that consist of
activities promoting gender equality, and observers. Among the latter, CERN collecting a general overview on the
and to discuss gender-oriented policies (the European Organization for Nuclear national situation (both in terms of gender
and best practice in the European Research), NordForsk (an organisation statistics and initiatives) and offering topi-
Research Area (with special emphasis that facilitates and provides funding cal workshops in the areas most relevant
on intergovernmental organisations), for Nordic research cooperation and to that country.
as well as the importance of building research infrastructure) and ESO, follow
NordForsk
In this spirit, CERN, NordForsk and ESO
decided to organise a Gender in Physics
Day, bringing in the perspective of inter-
governmental organisations and the chal-
lenges that such international research
infrastructures and funding agencies
face. All eight EIROforum organisations
were invited to join the event. The focus
of the day was on the recruitment, reten-
tion and career development of female
professionals in the field of science, engi-
neering and technology (SET).
Report on the
Bruno Dias1
ESO/F. Rodriguez
Julien Milli1
1
ESO
ESO/F. Rodriguez
ESO colleagues. We report here the out-
come and feedback from this pilot event.
0
0.5
0.4 10
0.3 5
0.2 0
Project 3 Extracting data from the
telescope log
0
0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
07
07
04
04
05
05
03
03
06
08
06
08
09
09
Leader: Daniel Asmus (Fellow)
10 5 100
Flux in ADU/aperture
IR DTTS
80
104 Vis WFS Similarly to Project 2, the participants
Strehl (%)
0
0
0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
:0
07
07
04
04
05
05
03
06
08
03
06
08
09
09
graph (FLAMES), and the VIsible Multi-
Seeing in arcsec, 0 /10 in ms and Strehl (size prop. to WFS flux)
HD135344B_IRDIS_DPI_1
GJ-3915
EUDel-ZIMPOL-P2_nocor_V_3
47-Tuc
HD201219_IRDIFS
HD-222038
HIP-109268
0
0
:0
:0
:0
:0
:0
:0
07
04
05
03
06
08
09
5
Project 6 Reading and inspecting
data using pandas
Fellows at ESO
sorts of experiments in electronics, al. 2016, A&A 596, A97) in which, for the
optics, chemistry and biology. We would first time, the chemical properties of the
make field trips with experts in geology, gas in the Galaxy and in distant galaxies
and astronomy too. So I had no doubt were characterised in a unified picture. In
that I would enroll in a science high particular, we derived the properties of
school later. Soon I learned to have fun the dust and the dust-corrected metallic-
with mathematics and physics, and ity in the interstellar medium.
became more and more curious about
how things work in the Universe. While I have used Very Large Telescope
(VLT) observations for my science, I now
The University of Bologna was my next have the opportunity to be a night astron-
step, where I got both Bachelor and omer on Paranal. As an ESO fellow, I am
Masters Degrees in Astronomy and observing with Kueyen (Unit Telescope 2),
Astrophysics. As part of my Masters, I driving the UV-Visual Echelle Spectro-
spent almost a year at the University of graph (UVES), the Fibre Large Array Multi
Calgary, Canada. Back in Italy for my Element Spectrograph (FLAMES) and the
Masters thesis, I worked at the Astro- X-shooter spectrograph through their
physics Institute (INAF/IASF) on the X-ray diverse science objectives, and learning
properties of a low-luminosity active more deeply the science operations at
galactic nucleus. While writing my thesis, the Observatory, appreciating the excel-
I remember receiving an email regarding lence of these world-leading facilities,
a PhD project on even more energetic and participating in ensuring that the
and mysterious phenomena, gamma-ray observations run smoothly and efficiently,
bursts (GRBs), and their environments. thereby enabling the best science from
And in Iceland. Poyekhali!* Annalisa De Cia the collected data. Enjoying a red sunset
at the platform, watching the Sun melting
Without hesitation, I took up the chal- Factory. In particular, I started to work into the clouds over the Andes (always
lenge, and set off on a new adventure. on superluminous supernovae (SLSNe), hoping for a green flash) and the VLT
This was in 2008. The Centre for Astro- the most luminous SNe in the Universe, showing its majesty, I feel lucky. None of
physics and Cosmology, University of whose origin is a hot and still debated this would have been possible without
Iceland, was a small but warm and stimu- field. In the meantime, I became more the many brilliant people who guided or
lating astronomy group, which nurtured and more fascinated by small distant inspired me through my journey. I have
my scientific growth and also encouraged galaxies, so faint as to elude normal not named any of them here, but I am
my independence by supporting visits observations. But we can use bright and grateful to every single one of them. The
and extended projects abroad with my distant background sources, such as journey is not over, and I am looking for-
external collaborators, such as at the quasars, GRBs, or SLSNe, to probe their ward to what will be next! And I hope that
Dark Cosmology Centre (Denmark), ESO gas properties in incomparable detail. science will continue to drive my dreams.
in Chile and the University of Leicester In particular, I started to study the metals
(UK). My PhD years went by excitingly and dust within these distant systems,
between science, aeroplanes and vol- also known as Damped Lyman- Absorb- Jorge Lillo Box
canic eruptions. I am still dreaming about ers (DLAs). The Middle East revealed
the tremendous and exotic beauty of Ice- itself as a very intriguing land, with an Astronomy, with its link to philosophy, is
landic nature. impressive historical heritage. But unfor- probably one of the oldest sciences in
tunately with a complex and painful mili- the history of human beings. Our current
During a conference in Nikko, Japan, I tary and political struggle continuing. job is nothing but a technological
had learned to appreciate the scientific improvement and knowledge accumu
excellence of the Experimental Astro- In time, I developed a strong European lation over the centuries, building on
physics Group of the Weizmann Institute feeling, and so I decided to move to a what the Mayas did in Central America,
of Science, Israel. So the science call, major astronomical organisation in what the philosophers did in ancient
and (literally) favourable winds, took me Europe. I started at ESO as a fellow in Greece, what Hypatia and her disciples
south, to the opposite side of Europe. September 2015, and immediately found did in Alexandria, what the Rapa Nui
At Weizmann, I was introduced to the myself loving the place, and being involved did in Easter Island, etc. Nothing more,
world of supernovae (SNe), and became in observational and scientific activities, nothing less.
part of a very active and cutting-edge such as the Gas Matters club, which
supernova survey, the Palomar Transient my colleagues and I founded to bring the Becoming an astronomer is a long jour-
Garching community together and dis- ney, and many different paths can lead
cuss the multi-phase gas inside and out- to this final goal. I am pretty sure each
side galaxies. Scientifically, I have just of us has a different story in answer
* Russian for Lets go!, Yuri Gagarin, 1961 published an extensive work (De Cia et to the question How did I become an
Personnel Movements
Europe Europe
Czepanski, Jasna (DE) Administrative Assistant Bhardwaj, Anupam (IN) Student
Flrs, Andreas (DE) Student Cortes, Angela (CL) Instrumentation Engineer
Franois, Mylne (FR) Administrative and Document Lampinen, Mervi Johanna (FI) Head of Information
Management Assistant Technology Department
George, Elizabeth (US) Detector Engineer Mc Leod, Anna Faye (FR) Student
Guglielmetti, Fabrizia (IT) ALMA Pipeline Processing Analyst Rabanus, David (DE) Electronics Engineer
Harrison, Christopher (UK) Fellow Turner, Owen James (UK) Student
Haug, Marcus (DE) Cryogenic Systems Engineer
Lelli, Federico (IT) Fellow
Lucchesi, Romain (FR) Student
Montesino Pouzols, Federico (ES) Software Engineer
Mller, Eric (DE) Instrumentation Engineer
Nogueras Lara, Francisco (ES) Student
Chile Chile
Aguilar, Max (CL) Hospitality Operations Supervisor Guzman, Lizette (MX) Fellow
Carcamo, Carolina (CL) Procurement Officer
Cardenas, Mauricio (CL) Telescope Instruments Operator
Ciechanowicz, Miroslaw (PL) Senior Electronics Engineer
Muoz, Miguel Patricio (CL) Electronics Technician
Muoz, Ingeborg (CL) Unix-Database Specialist
Rojas, Alejandra (CL) Student
Santamara Miranda, Alejandro (ES) Student
ESO/S. Fandango
Subject Index VLT/VLTI Second-Generation Instrumentation: The LEGA-C Survey: The Physics of Galaxies 7 Gyr
Lessons Learned; Gilmozzi, R.; Pasquini, L.; Ago; van der Wel, A.; Noeske, K.; Bezanson, R.;
Russell, A.; 166, 29 Pacifici, C.; Gallazzi, A.; Franx, M.; Muoz-Mateos,
The Organisation Science-Grade Imaging Data for HAWK-I, VIMOS, J.-C.; Bell, E. F.; Brammer, G.; Charlot, S.;
and VIRCAM: The ESOUK Pipeline Chauk, P.; Labb, I.; Maseda, M. V.; Muzzin, A.;
The Signing of the ALMA Trilateral Agreement; Gube, Collaboration; Neeser, M.; Lewis, J.; Madsen, G.; Rix, H.-W.; Sobral, D.; van de Sande, J.; van
N.; de Zeeuw, T.; 163, 2 Yoldas, A.; Irwin, M.; Gabasch, A.; Coccato, L.; Dokkum, P. G.; Wild, V.; Wolf, C.; 164, 36
Reaching New Heights in Astronomy ESO Long Garca-Dab, C. E.; Romaniello, M.; Freudling, W.; ALMACAL: Exploiting ALMA Calibrator Scans to
Term Perspectives; de Zeeuw, T.; 166, 2 Ballester, P.; 166, 36 Carry Out a Deep and Wide (Sub)millimetre
Annual Index 2015; ESO; 163, 60 Stereo-SCIDAR: Instrument and First Commissioning Survey, Free of Cosmic Variance; Oteo, I.; Zwaan,
Results; Derie, F.; Wilson, R.; Osborn, J.; M.; Ivison, R.; Smail, I.; Biggs, A.; 164, 41
Dubbeldam, M.; Sarazin, M.; Ridings, R.; Globular Clusters and the Milky Way Connected by
Telescopes and Instrumentation Navarrete, J.; Lelouarn, M.; 166, 41 Chemistry; Dias, B.; Saviane, I.; Barbuy, B.; Held,
E. V.; Da Costa, G.; Ortolani, S.; Gullieuszik, M.;
The Growth of the User Community of the La Silla 165, 19
Paranal Observatory Science Archive; Romaniello, Astronomical Science Connecting the Dots: MUSE Unveils the Destructive
M.; Arnaboldi, M.; Da Rocha, C.; De Breuck, C.; Effect of Massive Stars; McLeod, A. F.; Ginsburg,
Delmotte, N.; Dobrzycki, A.; Fourniol, N.; New Eyes on the Sun Solar Science with ALMA; A.; Klaassen, P.; Mottram, J.; Ramsay, S.; Testi,
Freudling, W.; Mascetti, L.; Micol, A.; Retzlaff, J.; Wedemeyer, S.; 163, 15 L.; 165, 22
Sterzik, M.; Vera Sequeiros, I.; Vuong De Breuck, The Central Role of FORS1/2 Spectropolarimetric From ATLASGAL to SEDIGISM: Towards a Complete
M.; 163, 5 Observations for the Progress of Stellar 3D View of the Dense Galactic Interstellar
FORS2 Rotating Flat Field Systematics Fixed Magnetism Studies; Schller, M.; Hubrig, S.; Ilyin, Medium; Schuller, F.; Urquhart, J.; Bronfman, L.;
Recent Exchange of FORS LADC Prisms I.; Steffen, M.; Briquet, M.; Kholtygin, A. F.; 163, Csengeri, T.; Bontemps, S.; Duarte-Cabral, A.;
Improves the Long-known Flat-fielding Problem; 21 Giannetti, A.; Ginsburg, A.; Henning, T.; Immer, K.;
Boffin, H.; Moehler, S.; Freudling, W.; 163, 10 The QUESTLa Silla AGN Variability Survey; Cartier, Leurini, S.; Mattern, M.; Menten, K.; Molinari, S.;
A Simpler Procedure for Specifying Solar System R.; Lira, P.; Coppi, P.; Snchez, P.; Arvalo, P.; Muller, E.; Snchez-Monge, A.; Schisano, E.; Suri,
Objects in Phase 2; Carry, B.; Berthier, J.; 163, 12 Bauer, F. E.; Muoz, R. R.; 163, 26 S.; Testi, L.; Wang, K.; Wyrowski, F.; Zavagno, A.;
Adaptive Optics Facility Status Report: When First Towards a Fundamental Astrometric Reference 165, 27
Light Is Produced Rather Than Captured; System behind the Magellanic Clouds: Ultra-deep K-band Imaging of the Hubble Frontier
Arsenault, R.; Madec, P.-Y.; Vernet, E.; Spectroscopic Confirmation of New Quasar Fields; Brammer, G. B.; Marchesini, D.; Labb, I.;
Hackenberg, W.; Bonaccini Calia, D.; La Penna, Candidates Selected in the Near-infrared; Ivanov, Spitler, L.; Lange-Vagle, D.; Barker, E. A.; Tanaka,
P.; Paufique, J.; Kuntschner, H.; Pirard, J.-F.; V. D.; Cioni, M.-R. L.; Bekki, K.; de Grijs, R.; M.; Fontana, A.; Galametz, A.; Ferr-Mateu, A.;
Sarazin, M.; Haguenauer, P.; Hubin, N.; Vera, I.; Emerson, J.; Gibson, B. K.; Kamath, D.; van Loon, Kodama, T.; Lundgren, B.; Martis, N.; Muzzin, A.;
164, 2 J. Th.; Piatti, A. E.; For, B.-Q.; 163, 32 Stefanon, M.; Toft, S.; van der Wel, A.; Vulcani, B.;
A Fruitful Collaboration between ESO and the Max The KMOS AGN Survey at High Redshift (KASHz); Whitaker, K. E.; 165, 34
Planck Computing and Data Facility; Fourniol, N.; Harrison, C.; Alexander, D.; Mullaney, J.; Stott, J.; A Deep ALMA Image of the Hubble Ultra Deep Field;
Zampieri, S.; Panea, M.; 164, 8 Swinbank, M.; Arumugam, V.; Bauer, F.; Bower, Dunlop, J. S.; 166, 48
Solar Activity-driven Variability of Instrumental Data R.; Bunker, A.; Sharples, R.; 163, 35 First ALMA Detection of a Galaxy Cluster Merger
Quality; Martayan, C.; Smette, A.; Hanuschik, R.; A Stellar Census in NGC 6397 with MUSE; Kamann, Shock; Basu, K.; Sommer, M.; Erler, J.; Eckert, D.;
van Der Heyden, P.; Mieske, S.; 164, 10 S.; Husser, T.-O.; Wendt, M.; Bacon, R.; Vazza, F.; Magnelli, B.; Bertoldi, F.; Tozzi, P.; 166,
Science Verification for the VISIR Upgrade; Asmus, Brinchmann, J.; Dreizler, S.; Emsellem, E.; 53
D.; van den Ancker, M.; Ivanov, V.; Kufl, H.-U.; Krajnovi, D.; Monreal-Ibero, A.; Roth, M. M.;
Kerber, F.; Leibundgut, B.; Mehner, A.; Momany, Weilbacher, P. M.; Wisotzki, L.; 164, 18
Y.; Pantin, E.; Tristram, K. R. W.; 164, 14 Pulsating Hot Subdwarfs in Omega Centauri; Astronomical News
Gender Systematics in Telescope Time Allocation at Randall, S. K.; Calamida, A.; Fontaine, G.; Monelli,
ESO; Patat, F.; 165, 2 M.; Bono, G.; Alonso, M. L.; Van Grootel, V.; Light Phenomena over the ESO Observatories I:
The Next Generation Transit Survey Becomes Brassard, P.; Chayer, P.; Catelan, M.; Littlefair, S.; Airglow; Christensen, L. L.; Noll, S.; Horlek, P.;
Operational at Paranal; West, R. G.; Pollacco, D.; Dhillon, V. S.; Marsh, T. R.; 164, 23 163, 40
Wheatley, P.; Goad, M.; Queloz, D.; Rauer, H.; First Results from the XXL Survey and Associated Light Phenomena over the ESO Observatories II:
Watson, C.; Udry, S.; Bannister, N.; Bayliss, D.; Multi-wavelength Programmes; Adami, C.; Pierre, Red Sprites; Horlek, P.; Christensen, L. L.; Br,
Bouchy, F.; Burleigh, M.; Cabrera, J.; Chaushev, M.; Baran, N.; Eckert, D.; Fotopoulou, S.; Giles, P. J.; Setvk, M.; 163, 43
A.; Chazelas, B.; Crausaz, M.; Csizmadia, S.; A.; Koulouridis, E.; Lidman, C.; Lieu, M.; Mantz, A. Report on the ESOESA Workshop Science
Eigmller, P.; Erikson, A.; Genolet, L.; Gillen, E.; B.; Pacaud, F.; Pompei, E.; Smoli, V.; Ziparo, F.; Operations 2015: Science Data Management;
Grange, A.; Gnther, M.; Hodgkin, S.; Kirk, J.; XXL Team; 164, 27 Romaniello, M.; Arviset, C.; Leibundgut, B.;
Lambert, G.; Louden, T.; McCormac, J.; Metrailler, Lennon, D.; Sterzik, M.; 163, 46
L.; Neveu, M.; Smith, A.; Thompson, A.; Raddi, R.; Report on European Radio Interferometry School
Walker, S. R.; Jenkins, J.; Jordn, A.; 165, 10 2015; Laing, R.; Richards, A.; 163, 50
SEPIA A New Instrument for the Atacama The AstroMundusESO Connection; Humphreys, L.;
Pathfinder Experiment (APEX) Telescope; Immer, Hussain, G.; Biggs, A.; Lu, H.-Y.; Emsellem, E.; De
K.; Belitsky, V.; Olberg, M.; De Breuck, C.; Cia, A.; Lavail, A.; Spyromilio, J.; 163, 51
Conway, J.; Montenegro-Montes, F. M.; Perez- Gert Finger Becomes Emeritus Physicist; de Zeeuw,
Beaupuits, J.-P.; Torstensson, K.; Billade, B.; De T.; Lucuix, C.; Pron, M.; 163, 53
Beck, E.; Ermakov, A.; Ferm, S.-E.; Fredrixon, M.;
Fellows at ESO; McClure, M.; Milli, J.; Ginsburg, A.;
Lapkin, I.; Meledin, D.; Pavolotsky, A.; Strandberg,
163, 54
M.; Sundin, E.; Arumugam, V.; Galametz, M.;
Humphreys, E.; Klein, T.; Adema, J.; Barkhof, J.; Personnel Movements; ESO; 163, 57
Baryshev, A.; Boland, W.; Hesper, R.; Klapwijk, T. ESO Studentship Programme 2016/2017; ESO; 163,
M.; 165, 13 58
Light Phenomena over the ESO Observatories III: Report on the ESO/MPA /MPE/Excellence Cluster/ Personnel Movements; ESO; 165, 53
Zodiacal Light; Horlek, P.; Christensen, L. L.; LMU and TUM Munich Joint Conference Discs in Resolving Planet Formation in the Era of ALMA and
Nesvorn, D.; Davies, R.; 164, 45 Galaxies; Ellis, R.; 165, 39 Extreme AO Report on the joint ESO/NRAO
The First NEON School in La Silla; Dennefeld, M.; Report on the ESO Workshop Active Galactic Conference; Dent, W. R. F.; Hales, A.; Milli, J.;
Melo, C.; Selman, F.; 164, 47 Nuclei: whats in a name?; Padovani, P.; 165, 44 166, 59
Report on the ESO Data Simulation Workshop; Report on the ESO/OPTICON Instrumentation Very Large Telescope Adaptive Optics Community
Ballester, P.; 164, 50 School on Use and Data Reduction of X-shooter Days Report on the ESO Workshop; Leibundgut,
Retirement of Lothar Noethe; Spyromilio, J.; and KMOS; Ballester, P.; Dennefeld M.; 165, 45 B.; Kasper, M.; Kuntschner, H.; 166, 62
Holzlhner, R.; 164, 52 Report on the ALMA Developers Workshop; Laing, Claus Madsen Retires; de Zeeuw, T.; Walsh, J.; 166,
Fellows at ESO; Immer, K.; Johnston, E.; Kerzendorf, R.; Mroczkowski, T.; Testi, L.; 165, 47 65
W.; 164, 54 Fellows at ESO; Visser, R.; Watson, L.; Asmus, D.; Retirement of Dietrich Baade; Walsh, J.; 166, 66
Personnel Movements; ESO; 164, 57 165, 49 Fellows at ESO; Jaff, Y.; Stroe, A.; Xu, S.; 166, 68
ESO Fellowship Programme 2016/2017; ESO; 164, ESO Studentship Programme 2016 2nd Call; Personnel Movements; ESO; 166, 71
58 ESO; 165, 52
Author Index Brammer, G. B.; Marchesini, D.; Labb, I.; Spitler, L.; Dias, B.; Saviane, I.; Barbuy, B.; Held, E. V.; Da
Lange-Vagle, D.; Barker, E. A.; Tanaka, M.; Costa, G.; Ortolani, S.; Gullieuszik, M.; Globular
Fontana, A.; Galametz, A.; Ferr-Mateu, A.; Clusters and the Milky Way Connected by
A Kodama, T.; Lundgren, B.; Martis, N.; Muzzin, A.; Chemistry; 165, 19
Stefanon, M.; Toft, S.; van der Wel, A.; Vulcani, B.; Dunlop, J. S.; A Deep ALMA Image of the Hubble
Adami, C.; Pierre, M.; Baran, N.; Eckert, D.; Whitaker, K. E.; Ultra-deep K-band Imaging of the Ultra Deep Field; 166, 48
Fotopoulou, S.; Giles, P. A.; Koulouridis, E.; Hubble Frontier Fields; 165, 34
Lidman, C.; Lieu, M.; Mantz, A. B.; Pacaud, F.;
Pompei, E.; Smoli, V.; Ziparo, F.; XXL Team; E
First Results from the XXL Survey and Associated C
Multi-wavelength Programmes; 164, 27 Ellis, R.; Report on the ESO/MPA /MPE/Excellence
Arsenault, R.; Madec, P.-Y.; Vernet, E.; Hackenberg, Carry, B.; Berthier, J.; A Simpler Procedure for Cluster/LMU and TUM Munich Joint Conference
W.; Bonaccini Calia, D.; La Penna, P.; Paufique, J.; Specifying Solar System Objects in Phase 2; 163, Discs in Galaxies; 165, 39
Kuntschner, H.; Pirard, J.-F.; Sarazin, M.; 12
Haguenauer, P.; Hubin, N.; Vera, I.; Adaptive Cartier, R.; Lira, P.; Coppi, P.; Snchez, P.; Arvalo,
Optics Facility Status Report: When First Light Is P.; Bauer, F. E.; Muoz, R. R.; The QUEST G
Produced Rather Than Captured; 164, 2 La Silla AGN Variability Survey; 163, 26
Asmus, D.; van den Ancker, M.; Ivanov, V.; Kufl, Christensen, L. L.; Noll, S.; Horlek, P.; Light Gilmozzi, R.; Pasquini, L.; Russell, A.; VLT/VLTI
H.-U.; Kerber, F.; Leibundgut, B.; Mehner, A.; Phenomena over the ESO Observatories I: Second-Generation Instrumentation: Lessons
Momany, Y.; Pantin, E.; Tristram, K. R. W.; Science Airglow; 163, 40 Learned; 166, 29
Verification for the VISIR Upgrade; 164, 14 Gube, N.; de Zeeuw, T.; The Signing of the ALMA
Trilateral Agreement; 163, 2
D
B
de Zeeuw, T.; Lucuix, C.; Pron, M.; Gert Finger H
Ballester, P.; Report on the ESO Data Simulation Becomes Emeritus Physicist; 163, 53
Workshop; 164, 50 Harrison, C.; Alexander, D.; Mullaney, J.; Stott, J.;
de Zeeuw, T.; Reaching New Heights in Astronomy
Ballester, P.; Dennefeld M.; Report on the ESO/ ESO Long Term Perspectives; 166, 2 Swinbank, M.; Arumugam, V.; Bauer, F.; Bower,
OPTICON Instrumentation School on Use and R.; Bunker, A.; Sharples, R.; The KMOS AGN
de Zeeuw, T.; Walsh, J.; Claus Madsen Retires; 166,
Data Reduction of X-shooter and KMOS; 165, 45 Survey at High Redshift (KASHz); 163, 35
65
Basu, K.; Sommer, M.; Erler, J.; Eckert, D.; Vazza, F.; Horlek, P.; Christensen, L. L.; Br, J.; Setvk, M.;
Dennefeld, M.; Melo, C.; Selman, F.; The First NEON
Magnelli, B.; Bertoldi, F.; Tozzi, P.; First ALMA Light Phenomena over the ESO Observatories II:
School in La Silla; 164, 47
Detection of a Galaxy Cluster Merger Shock; 166, Red Sprites; 163, 43
53 Dent, W. R. F.; Hales, A.; Milli, J.; Resolving Planet
Formation in the Era of ALMA and Extreme AO Horlek, P.; Christensen, L. L.; Nesvorn, D.; Davies,
Boffin, H.; Moehler, S.; Freudling, W.; FORS2 R.; Light Phenomena over the ESO Observatories
Report on the joint ESO/NRAO Conference; 166,
Rotating Flat Field Systematics Fixed Recent III: Zodiacal Light; 164, 45
59
Exchange of FORS LADC Prisms Improves the Humphreys, L.; Hussain, G.; Biggs, A.; Lu, H.-Y.;
Long-known Flat-fielding Problem; 163, 10 Derie, F.; Wilson, R.; Osborn, J.; Dubbeldam, M.;
Sarazin, M.; Ridings, R.; Navarrete, J.; Lelouarn, Emsellem, E.; De Cia, A.; Lavail, A.; Spyromilio, J.;
M.; Stereo-SCIDAR: Instrument and First The AstroMundusESO Connection; 163, 51
Commissioning Results; 166, 41
Immer, K.; Johnston, E.; Kerzendorf, W.; Fellows at Martayan, C.; Smette, A.; Hanuschik, R.; van Der Schller, M.; Hubrig, S.; Ilyin, I.; Steffen, M.; Briquet,
ESO; 164, 54 Heyden, P.; Mieske, S.; Solar Activity-driven M.; Kholtygin, A. F.; The Central Role of FORS1/2
Immer, K.; Belitsky, V.; Olberg, M.; De Breuck, C.; Variability of Instrumental Data Quality; 164, 10 Spectropolarimetric Observations for the
Conway, J.; Montenegro-Montes, F. M.; Perez- McClure, M.; Milli, J.; Ginsburg, A.; Fellows at ESO; Progress of Stellar Magnetism Studies; 163, 21
Beaupuits, J.-P.; Torstensson, K.; Billade, B.; De 163, 54 Schuller, F.; Urquhart, J.; Bronfman, L.; Csengeri, T.;
Beck, E.; Ermakov, A.; Ferm, S.-E.; Fredrixon, M.; McLeod, A. F.; Ginsburg, A.; Klaassen, P.; Mottram, Bontemps, S.; Duarte-Cabral, A.; Giannetti, A.;
Lapkin, I.; Meledin, D.; Pavolotsky, A.; Strandberg, J.; Ramsay, S.; Testi, L.; Connecting the Dots: Ginsburg, A.; Henning, T.; Immer, K.; Leurini, S.;
M.; Sundin, E.; Arumugam, V.; Galametz, M.; MUSE Unveils the Destructive Effect of Massive Mattern, M.; Menten, K.; Molinari, S.; Muller, E.;
Humphreys, E.; Klein, T.; Adema, J.; Barkhof, J.; Stars; 165, 22 Snchez-Monge, A.; Schisano, E.; Suri, S.; Testi,
Baryshev, A.; Boland, W.; Hesper, R.; Klapwijk, T. L.; Wang, K.; Wyrowski, F.; Zavagno, A.; From
M.; SEPIA A New Instrument for the Atacama ATLASGAL to SEDIGISM: Towards a Complete 3D
Pathfinder Experiment (APEX) Telescope; 165, 13 N View of the Dense Galactic Interstellar Medium;
Ivanov, V. D.; Cioni, M.-R. L.; Bekki, K.; de Grijs, R.; 165, 27
Emerson, J.; Gibson, B. K.; Kamath, D.; van Loon, Neeser, M.; Lewis, J.; Madsen, G.; Yoldas, A.; Irwin, Spyromilio, J.; Holzlhner, R.; Retirement of Lothar
J. Th.; Piatti, A. E.; For, B.-Q.; Towards a M.; Gabasch, A.; Coccato, L.; Garca-Dab, C. E.; Noethe; 164, 52
Fundamental Astrometric Reference System Romaniello, M.; Freudling, W.; Ballester, P.;
behind the Magellanic Clouds: Spectroscopic Science-Grade Imaging Data for HAWK-I, VIMOS,
Confirmation of New Quasar Candidates Selected and VIRCAM: The ESOUK Pipeline V
in the Near-infrared; 163, 32 Collaboration; 166, 36
van der Wel, A.; Noeske, K.; Bezanson, R.; Pacifici,
C.; Gallazzi, A.; Franx, M.; Muoz-Mateos, J.-C.;
J O Bell, E. F.; Brammer, G.; Charlot, S.; Chauk, P.;
Labb, I.; Maseda, M. V.; Muzzin, A.; Rix, H.-W.;
Jaff, Y.; Stroe, A.; Xu, S.; Fellows at ESO; 166, 68 Oteo, I.; Zwaan, M.; Ivison, R.; Smail, I.; Biggs, A.; Sobral, D.; van de Sande, J.; van Dokkum, P. G.;
ALMACAL: Exploiting ALMA Calibrator Scans to Wild, V.; Wolf, C.; The LEGA-C Survey: The
Carry Out a Deep and Wide (Sub)millimetre Physics of Galaxies 7 Gyr Ago; 164, 36
K Survey, Free of Cosmic Variance; 164, 41 Visser, R.; Watson, L.; Asmus, D.; Fellows at ESO;
165, 49
Kamann, S.; Husser, T.-O.; Wendt, M.; Bacon, R.;
Brinchmann, J.; Dreizler, S.; Emsellem, E.; P
Krajnovi, D.; Monreal-Ibero, A.; Roth, M. M.; W
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NGC 6397 with MUSE; 164, 18 Galactic Nuclei: whats in a name?; 165, 44 Walsh, J.; Retirement of Dietrich Baade; 166, 66
Patat, F.; Gender Systematics in Telescope Time Wedemeyer, S.; New Eyes on the Sun Solar
Allocation at ESO; 165, 2 Science with ALMA; 163, 15
L West, R. G.; Pollacco, D.; Wheatley, P.; Goad, M.;
Queloz, D.; Rauer, H.; Watson, C.; Udry, S.;
Laing, R.; Richards, A.; Report on European Radio R Bannister, N.; Bayliss, D.; Bouchy, F.; Burleigh, M.;
Interferometry School 2015; 163, 50 Cabrera, J.; Chaushev, A.; Chazelas, B.; Crausaz,
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Laing, R.; Mroczkowski, T.; Testi, L.; Report on the
M.; Bono, G.; Alonso, M. L.; Van Grootel, V.; Genolet, L.; Gillen, E.; Grange, A.; Gnther, M.;
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Brassard, P.; Chayer, P.; Catelan, M.; Littlefair, S.; Hodgkin, S.; Kirk, J.; Lambert, G.; Louden, T.;
Leibundgut, B.; Kasper, M.; Kuntschner, H.; Very Dhillon, V. S.; Marsh, T. R.; Pulsating Hot McCormac, J.; Metrailler, L.; Neveu, M.; Smith, A.;
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Data Management; 163, 46
ESO Headquarters
Front cover: An album of images and spectra of SN 1987A tracing
Karl-Schwarzschild-Strae 2 The Messenger
the evolution of the supernova observed with ESO facilities:
85748 Garching bei Mnchen, Germany
1. T
he Large Magellanic Cloud (LMC) before explosion of
Phone +49 89 320 06-0 SN1987A; ESO 1-metre Schmidt optical image.
information@eso.org 2. SN 1987A close to its peak brightness; ESO Schmidt image
1 2
in optical.
The Messenger: 3
3. Optical spectral evolution of SN 1987A over first 110 days; 4
Editor: Jeremy R. Walsh; sequence with Bochum telescope (from Hanuschik & Thimm, 6
Design, Production: Jutta Boxheimer; 1990, A&A, 231, 77). 5
L ayout, Typesetting: Mafalda Martins; 4. Light echoes around SN 1987A; NTT H image from 1992. 7
Graphics: E d Janssen. 5. ISAAC broad slit spectrum centred on He I 1.083 m line
9
www.eso.org/messenger/ from 1999. 8
6. U VES spectrum centred on H taken in 1999.
Printed by G. Peschke Druckerei GmbH 7. E
arly NTT [N II] 6583 image of SN 1987A from 1991.
Taxetstrae 4, 8. NACO near-infrared adaptive optics image from 2006.
9. Composite sub-mm (ALMA, in red), visible light (Hubble Space
85599 Parsdorf, Germany
Telecope in green) and Chandra X-ray image (in blue) of the
current appearance, and released for the 30th anniversary.
Unless otherwise indicated, all images See ESO Picture of the Week potw1709 for details.
in The Messenger are courtesy of ESO,
except authored contributions which Credits: 18 all ESO | 9. ALMA: ESO/NAOJ/NRAO/A. Angelich;
are courtesy of the respective authors. Hubble: NASA, ESA, R. Kirshner (Harvard-Smithsonian Center
for Astrophysics and Gordon and Betty Moore Foundation)
ESO 2017 and P. Challis (Harvard-Smithsonian Center for Astrophysics);
ISSN0722-6691 Chandra: NASA/CXC/Penn State/K. Frank et al.