Here are two points or questions that I would like to share:
1. I would like to propose that another scenario be added to Table 1. Is it too late? It will be nice to add benchmark points from the MSSM-30.
2. It will be interesting to know whether the proposed benchmarks have passed the new limit from ACME about the possibility for an electron to have an electric dipole moment.
Many thanks for your comments. Here are our replies:
1. It is too late now to include a new scenario in this public note. If you wish to propose that the LHCHWG considers another (published) MSSM scenario for future inclusion in the ROOT files, feel free to contact the conveners of the MSSM subgroup with the details. It will certainly be discussed.
2. The phase for At used in the CPV scenario is excluded by the recent ACME bound, unless one invokes subtle cancellations between different contributions to the EDM. There are however various reasons why the scenario is still of interest. These were discussed in Ref. [13], to which we consistently refer the readers for all discussions that concern the phenomenology of the scenarios of section 2.3. We added a footnote to the final sentence of section 2.3.7:
"See also the note added at the end of Ref. [13] for a discussion of the implications of the ACME bound~\cite{ACME:2018yjb} on the electric dipole moment of the electron."
This comment is related with file LHCHWG-2021-001, version 1
Dear authors,
Thank you very much for writing this note! It is a very nice summary of all state-of-the-art MSSM benchmark scenarios proposed by LHCHWG so far, pointing out their important features, and describing technical details on how to use them. All in all - a very good starting point for each experimental group to get familiar with the scenarios and the corresponding ROOT files, and therefore an important milestone. Congratulations!
You can find my detailed comments in the attachement. There are only a few comments related to the content at the beginning of the document, followed by comments on style and wording. Due to the lack of line numbers, I've just written down the comments in the order I was reading the document from front to end.
Looking forward to see the note published in its final form!
Thanks for your detailed reading of the note and for your many comments. We start by addressing those that refer to the scientific content of the note:
- sentence on the input parameters in the introduction:
The sentence you cite starts with "typically". It does not refer in particular to the scenarios discussed in this note, and it is not meant to be absolute. Note that, as mentioned towards the end of page 1, there is
even one CP-conserving scenario from Ref. [1] in which the other free parameter is mu.
- citing the ATLAS/CMS analyses that used the benchmark scenarios from 2013:
This document is meant as an instructions manual for the current version of the ROOT files. For maximal clarity, we decided to include only references to calculations that are directly used in the production of the ROOT files, and avoid both references that provide "historical context" for the calculations and references that concern the phenomenology of the various scenarios. In this context, citing the 26 published papers by
ATLAS and CMS that used the outdated scenarios of Ref. [1] would seem an unnecessary diversion to us.
- citing the Zenodo record:
We added the name of the record and the citation to the DOI number.
- sentence on the correct use of the interference factors:
We added a clarifying sentence at the end of section 3.4.
- syntax for BR(t-> Hp b):
We provided the explicit syntax for the call of the function "br" in the case of the top decay to charged Higgs boson.
- syntax for Higgs-strahlung cross sections:
Thank you for spotting this, it must be a residue of an earlier version in which the Z and W channels were not differentiated. The Higgs-strahlung channels are in fact named hs_Z and hs_W, so there is no problem. We just corrected the list of channels in the second line of page 23.
For what concerns your comments on wording and style, we do not view it as a particular problem if our document "has a bit of a jargon flavor". Being a technical document aimed at a limited group of specialists, it uses the shared jargon of that group. In particular, wording such as "branching ratio", "codes", and the occasional omission of "boson" when "Higgs" is used as an attribute (as in, e.g., "Higgs mass" instead of "Higgs-boson mass") is standard in our community, see e.g. the language of the four Yellow Reports of the LHCHXSWG. Following your suggestions, we have nevertheless implemented a number of changes in our text:
- We believe that our usage of hyphens is grammatically correct albeit perhaps not strictly necessary, but we agree that it should be applied consistently throughout the document. We have thus amended title and abstract.
- We added "boson" in several instances in which we were referring to "the Higgs" alone, rather than as an attribute of some other word.
- We clarified the sentence on the signal strength modifiers.
- We replaced "in contrast with" with "in contrast to".
- In section 5, we replaced all sentences of the kind "one/the user can/should do XYZ" with sentences of the kind "XYZ can/should be done".
For your convenience, we attach a PDF file that highlights the modifications in our text.
Thank you very much for taking into account my suggestions and comments, I'm happy with all answers you've given and the adjustments you've made.
Looking forward to see this note public!
Cheers,
Artur
Pietro Slavich wrote on 27 Dec 2021, 17:07:
Dear Artur,
Thanks for your detailed reading of the note and for your many comments. We start by addressing those that refer to the scientific content of the note:
- sentence on the input parameters in the introduction:
The sentence you cite starts with "typically". It does not refer in particular to the scenarios discussed in this note, and it is not meant to be absolute. Note that, as mentioned towards the end of page 1, there is
even one CP-conserving scenario from Ref. [1] in which the other free parameter is mu.
- citing the ATLAS/CMS analyses that used the benchmark scenarios from 2013:
This document is meant as an instructions manual for the current version of the ROOT files. For maximal clarity, we decided to include only references to calculations that are directly used in the production of the ROOT files, and avoid both references that provide "historical context" for the calculations and references that concern the phenomenology of the various scenarios. In this context, citing the 26 published papers by
ATLAS and CMS that used the outdated scenarios of Ref. [1] would seem an unnecessary diversion to us.
- citing the Zenodo record:
We added the name of the record and the citation to the DOI number.
- sentence on the correct use of the interference factors:
We added a clarifying sentence at the end of section 3.4.
- syntax for BR(t-> Hp b):
We provided the explicit syntax for the call of the function "br" in the case of the top decay to charged Higgs boson.
- syntax for Higgs-strahlung cross sections:
Thank you for spotting this, it must be a residue of an earlier version in which the Z and W channels were not differentiated. The Higgs-strahlung channels are in fact named hs_Z and hs_W, so there is no problem. We just corrected the list of channels in the second line of page 23.
For what concerns your comments on wording and style, we do not view it as a particular problem if our document "has a bit of a jargon flavor". Being a technical document aimed at a limited group of specialists, it uses the shared jargon of that group. In particular, wording such as "branching ratio", "codes", and the occasional omission of "boson" when "Higgs" is used as an attribute (as in, e.g., "Higgs mass" instead of "Higgs-boson mass") is standard in our community, see e.g. the language of the four Yellow Reports of the LHCHXSWG. Following your suggestions, we have nevertheless implemented a number of changes in our text:
- We believe that our usage of hyphens is grammatically correct albeit perhaps not strictly necessary, but we agree that it should be applied consistently throughout the document. We have thus amended title and abstract.
- We added "boson" in several instances in which we were referring to "the Higgs" alone, rather than as an attribute of some other word.
- We clarified the sentence on the signal strength modifiers.
- We replaced "in contrast with" with "in contrast to".
- In section 5, we replaced all sentences of the kind "one/the user can/should do XYZ" with sentences of the kind "XYZ can/should be done".
For your convenience, we attach a PDF file that highlights the modifications in our text.
But I am still hesitant about the second part. From my point of view, a scenario that is already ruled out by experiment should not be accepted as a benchmark for LHC studies. The footnote proposed only pushes the problem under the carpet since even the cited Ref.[13] did not resolve the issue. It is understandable for the case of Ref. [13] since perhaps the authors have submitted their article before or just around the corner of the ACME announcement. How about taking out the CP-violating scenario for now?
In all, the paper looks very good and the proposals very interesting.
It is not obvious to me that the chosen CPV phase is ruled out by ACME for all possible values of the other parameters of the scenario. Was this explicitly checked? That would require some significant scanning to be done. For this reason, I will agree with the CPV scenario as a benchmark if in the proposed footnote something along this discussion/question is added.
Many thanks for your replies. Concerning your last comment, the free parameters of the CPV scenario are the charged-Higgs mass and tanB, and the authors of ref.[13] had checked that the interesting region of the parameter space (the one with visible interference effects) is indeed ruled out by the latest ACME bound.
However, we should stress again that this note is meant as an instructions manual for the ROOT files that provide Higgs masses, BRs and cross sections in the MSSM benchmark scenarios. These files were made available on the Twiki pages of the LHCHWG some time ago, and they are already in use by the ATLAS and CMS collaborations for the interpretation within the MSSM of their searches for additional Higgs bosons. It is certainly legitimate to discuss whether the LHCHWG should add, remove or update any of the scenarios, but this should be done in the context of the future work of the MSSM subgroup, rather than in the publication process of the instructions manual of the ROOT files. Note that, even if the MSSM parameters that define the CPV scenario are eventually updated, the discussion of the interference factors in section 3.4 and the description of the file structure for the CPV case in section 4 will remain the same. Taking out the CPV scenario "for now" would needlessly remove relevant information from the note.
This said, we object to the characterization of the footnote to section 2.3.7 as "pushing the problem under the carpet", and we believe that the arguments put forward in the "note added" to ref.[13] as to why the CPV scenario introduced in that paper is still worth investigating remain valid even today. The main purpose of all of these benchmark scenarios is to highlight interesting phenomenological aspects of the Higgs sector – in the case of the CPV scenario, the interference effects that arise when multiple Higgs bosons mix with each other and are nearly mass-degenerate. Note that these effects are not specific to the MSSM, but can be found in general (SUSY or non-SUSY) BSM models with an extended Higgs sector. The inclusion of the CPV scenario in the suite of MSSM benchmark scenarios provided by the LHCHWG ensures that these effects are properly taken into account in the theoretical machinery used by ATLAS and CMS for the interpretation of the BSM Higgs searches.
Furthermore, note that the impact of the ACME bound on the CPV parameters crucially depends on the input value for the Yukawa coupling of the electron, which is essentially undetermined by experiment and has no impact on the heavy-Higgs phenomenology that is probed by the LHC searches. One could in principle devise small variations or extensions of the MSSM in which the bound does not apply. In a similar spirit, when defining the benchmark scenarios for MSSM Higgs searches, ref.[13] did not take into account constraints from flavor physics or from the dark matter relic density. These mainly apply to other sectors of the MSSM, and they could be accommodated via small variations of the model that do not affect Higgs phenomenology (e.g., small flavor-violating mass parameters in the scalar sector, or tiny
R-parity violating couplings).
Hello,
Here are two points or questions that I would like to share:
1. I would like to propose that another scenario be added to Table 1. Is it too late? It will be nice to add benchmark points from the MSSM-30.
2. It will be interesting to know whether the proposed benchmarks have passed the new limit from ACME about the possibility for an electron to have an electric dipole moment.
Cheers,
Shehu
Dear Shehu,
Many thanks for your comments. Here are our replies:
1. It is too late now to include a new scenario in this public note. If you wish to propose that the LHCHWG considers another (published) MSSM scenario for future inclusion in the ROOT files, feel free to contact the conveners of the MSSM subgroup with the details. It will certainly be discussed.
2. The phase for At used in the CPV scenario is excluded by the recent ACME bound, unless one invokes subtle cancellations between different contributions to the EDM. There are however various reasons why the scenario is still of interest. These were discussed in Ref. [13], to which we consistently refer the readers for all discussions that concern the phenomenology of the scenarios of section 2.3. We added a footnote to the final sentence of section 2.3.7:
"See also the note added at the end of Ref. [13] for a discussion of the implications of the ACME bound~\cite{ACME:2018yjb} on the electric dipole moment of the electron."
Best Regards,
The Authors
Dear authors,
Thank you very much for writing this note! It is a very nice summary of all state-of-the-art MSSM benchmark scenarios proposed by LHCHWG so far, pointing out their important features, and describing technical details on how to use them. All in all - a very good starting point for each experimental group to get familiar with the scenarios and the corresponding ROOT files, and therefore an important milestone. Congratulations!
You can find my detailed comments in the attachement. There are only a few comments related to the content at the beginning of the document, followed by comments on style and wording. Due to the lack of line numbers, I've just written down the comments in the order I was reading the document from front to end.
Looking forward to see the note published in its final form!
Cheers,
Artur
Comments_to_LHCHWG-2021-001_ArturGottmann.pdf
Dear Artur,
Thanks for your detailed reading of the note and for your many comments. We start by addressing those that refer to the scientific content of the note:
- sentence on the input parameters in the introduction:
The sentence you cite starts with "typically". It does not refer in particular to the scenarios discussed in this note, and it is not meant to be absolute. Note that, as mentioned towards the end of page 1, there is
even one CP-conserving scenario from Ref. [1] in which the other free parameter is mu.
- citing the ATLAS/CMS analyses that used the benchmark scenarios from 2013:
This document is meant as an instructions manual for the current version of the ROOT files. For maximal clarity, we decided to include only references to calculations that are directly used in the production of the ROOT files, and avoid both references that provide "historical context" for the calculations and references that concern the phenomenology of the various scenarios. In this context, citing the 26 published papers by
ATLAS and CMS that used the outdated scenarios of Ref. [1] would seem an unnecessary diversion to us.
- citing the Zenodo record:
We added the name of the record and the citation to the DOI number.
- sentence on the correct use of the interference factors:
We added a clarifying sentence at the end of section 3.4.
- syntax for BR(t-> Hp b):
We provided the explicit syntax for the call of the function "br" in the case of the top decay to charged Higgs boson.
- syntax for Higgs-strahlung cross sections:
Thank you for spotting this, it must be a residue of an earlier version in which the Z and W channels were not differentiated. The Higgs-strahlung channels are in fact named hs_Z and hs_W, so there is no problem. We just corrected the list of channels in the second line of page 23.
For what concerns your comments on wording and style, we do not view it as a particular problem if our document "has a bit of a jargon flavor". Being a technical document aimed at a limited group of specialists, it uses the shared jargon of that group. In particular, wording such as "branching ratio", "codes", and the occasional omission of "boson" when "Higgs" is used as an attribute (as in, e.g., "Higgs mass" instead of "Higgs-boson mass") is standard in our community, see e.g. the language of the four Yellow Reports of the LHCHXSWG. Following your suggestions, we have nevertheless implemented a number of changes in our text:
- We believe that our usage of hyphens is grammatically correct albeit perhaps not strictly necessary, but we agree that it should be applied consistently throughout the document. We have thus amended title and abstract.
- We added "boson" in several instances in which we were referring to "the Higgs" alone, rather than as an attribute of some other word.
- We clarified the sentence on the signal strength modifiers.
- We replaced "in contrast with" with "in contrast to".
- In section 5, we replaced all sentences of the kind "one/the user can/should do XYZ" with sentences of the kind "XYZ can/should be done".
For your convenience, we attach a PDF file that highlights the modifications in our text.
Best Regards,
The Authors
diff.pdf
Dear Pietro, all,
Thank you very much for taking into account my suggestions and comments, I'm happy with all answers you've given and the adjustments you've made.
Looking forward to see this note public!
Cheers,
Artur
Pietro Slavich wrote on 27 Dec 2021, 17:07:
Dear Pietro, and all,
I am happy with the first part of the answer.
But I am still hesitant about the second part. From my point of view, a scenario that is already ruled out by experiment should not be accepted as a benchmark for LHC studies. The footnote proposed only pushes the problem under the carpet since even the cited Ref.[13] did not resolve the issue. It is understandable for the case of Ref. [13] since perhaps the authors have submitted their article before or just around the corner of the ACME announcement. How about taking out the CP-violating scenario for now?
In all, the paper looks very good and the proposals very interesting.
Cheers,
Shehu
Hello all, again
It is not obvious to me that the chosen CPV phase is ruled out by ACME for all possible values of the other parameters of the scenario. Was this explicitly checked? That would require some significant scanning to be done. For this reason, I will agree with the CPV scenario as a benchmark if in the proposed footnote something along this discussion/question is added.
Cheers,
Shehu
Dear Shehu,
Many thanks for your replies. Concerning your last comment, the free parameters of the CPV scenario are the charged-Higgs mass and tanB, and the authors of ref.[13] had checked that the interesting region of the parameter space (the one with visible interference effects) is indeed ruled out by the latest ACME bound.
However, we should stress again that this note is meant as an instructions manual for the ROOT files that provide Higgs masses, BRs and cross sections in the MSSM benchmark scenarios. These files were made available on the Twiki pages of the LHCHWG some time ago, and they are already in use by the ATLAS and CMS collaborations for the interpretation within the MSSM of their searches for additional Higgs bosons. It is certainly legitimate to discuss whether the LHCHWG should add, remove or update any of the scenarios, but this should be done in the context of the future work of the MSSM subgroup, rather than in the publication process of the instructions manual of the ROOT files. Note that, even if the MSSM parameters that define the CPV scenario are eventually updated, the discussion of the interference factors in section 3.4 and the description of the file structure for the CPV case in section 4 will remain the same. Taking out the CPV scenario "for now" would needlessly remove relevant information from the note.
This said, we object to the characterization of the footnote to section 2.3.7 as "pushing the problem under the carpet", and we believe that the arguments put forward in the "note added" to ref.[13] as to why the CPV scenario introduced in that paper is still worth investigating remain valid even today. The main purpose of all of these benchmark scenarios is to highlight interesting phenomenological aspects of the Higgs sector – in the case of the CPV scenario, the interference effects that arise when multiple Higgs bosons mix with each other and are nearly mass-degenerate. Note that these effects are not specific to the MSSM, but can be found in general (SUSY or non-SUSY) BSM models with an extended Higgs sector. The inclusion of the CPV scenario in the suite of MSSM benchmark scenarios provided by the LHCHWG ensures that these effects are properly taken into account in the theoretical machinery used by ATLAS and CMS for the interpretation of the BSM Higgs searches.
Furthermore, note that the impact of the ACME bound on the CPV parameters crucially depends on the input value for the Yukawa coupling of the electron, which is essentially undetermined by experiment and has no impact on the heavy-Higgs phenomenology that is probed by the LHC searches. One could in principle devise small variations or extensions of the MSSM in which the bound does not apply. In a similar spirit, when defining the benchmark scenarios for MSSM Higgs searches, ref.[13] did not take into account constraints from flavor physics or from the dark matter relic density. These mainly apply to other sectors of the MSSM, and they could be accommodated via small variations of the model that do not affect Higgs phenomenology (e.g., small flavor-violating mass parameters in the scalar sector, or tiny
R-parity violating couplings).
Best Regards,
The Authors