|
1.
|
Effects of Cavity Pre-Detuning on RF Power Transients at Injection into the LHC
/ Karlsen-Bæck, Birk Emil (CERN ; Rome U.) ; Argyropoulos, Theodoros (CERN) ; Butterworth, Andrew (CERN) ; Calaga, Rama (CERN) ; Karpov, Ivan (CERN) ; Timko, Helga (CERN) ; Zampetakis, Michail (CERN)
At injection into the LHC, the RF system is perturbed by beam-induced voltage resulting in strong RF power transients and the instant detuning of the cavities. The automatic tuning system, however, needs time for the mechanical compensation of the resonance frequency to take place. [...]
2024 - 4 p.
- Published in : JACoW HB 2023 (2024) 530-533
Fulltext: PDF;
In : 68th ICFA Advanced Beam Dynamics workshop on high-Intensity and High-Brightness Hadron Beams (HB 2023), CERN, Geneva, Switzerland, 9 - 13 Oct 2023, pp.530-533
|
|
|
2.
|
|
|
3.
|
Mitigation Strategies for the Instabilities Induced by the Fundamental Mode of the HL-LHC Crab Cavities
/ Giacomel, Lorenzo (CERN) ; Baudrenghien, Philippe (CERN) ; Buffat, Xavier (CERN) ; Calaga, Rama (CERN) ; Mounet, Nicolas (CERN)
The transverse impedance is one of the potentially limiting effects for the performance of the High-Luminosity Large Hadron Collider (HL-LHC). In the current LHC, the impedance is dominated by the resistive-wall contribution of the collimators at typical bunch-spectrum frequencies, and is of broad-band nature. [...]
2024 - 4 p.
- Published in : JACoW HB 2023 (2024) 571-574
Fulltext: PDF;
In : 68th ICFA Advanced Beam Dynamics workshop on high-Intensity and High-Brightness Hadron Beams (HB 2023), CERN, Geneva, Switzerland, 9 - 13 Oct 2023, pp.571-574
|
|
|
4.
|
Overview of beam intensity issues and mitigations in the CERN-SPS fast wire scanners
/ Veness, Raymond (CERN) ; Guerrero, Ana (CERN) ; Perez Fontenla, Ana Teresa (CERN) ; Harrison, Anthony (CERN) ; Salvant, Benoit (CERN) ; Zannini, Carlo (CERN) ; Antuono, Chiara (CERN) ; Vollinger, Christine (CERN) ; de la Fuente, Elena (CERN) ; Carra, Federico (CERN) et al.
A new design of fast wire scanner was installed in the CERN injector complex as part of the upgrades linked to the High-Luminosity LHC Project. Initial operations with these beams were good, but during the planned intensity ramp-up one early 2023, all four SPS scanners failed at the same time. [...]
2024 - 4 p.
- Published in : JACoW IPAC 2024 (2024) WEPG26
Fulltext: PDF;
In : 15th International Particle Accelerator Conference (IPAC 2024), Nashville, TN, United States, 19 - 24 May 2024, pp.WEPG26
|
|
|
5.
|
Impedance and thermal studies of the CERN SPS wire scanners and mitigation of wire heating
/ de la Fuente, Elena (CERN) ; Papazoglou, I (CERN) ; Sito, Leonardo (CERN) ; Andreazza, William (CERN) ; Antuono, Chiara (CERN) ; Bruchon, N (CERN) ; Calaga, Rama (CERN) ; Carra, Federico (CERN) ; Emery, J (CERN) ; Harrison, Anthony (CERN) et al.
All wires of the four CERN SPS rotational wirescanners broke when increasing the beam intensity towards the target for the LHC Injector Upgrade in 2023. Impedance and thermal studies were immediately launched, with simulations and measurements indicating that beam induced heating from resonant modes on the thin wire could be sufficient to cause these breakages. [...]
2024 - 4 p.
- Published in : JACoW IPAC 2024 (2024) WEPG29
Fulltext: PDF;
In : 15th International Particle Accelerator Conference (IPAC 2024), Nashville, TN, United States, 19 - 24 May 2024, pp.WEPG29
|
|
|
6.
|
Emittance growth studies due to Crab Cavity induced amplitude noise in the SPS
/ Fornara, Andrea (Manchester U. ; CERN) ; Trad, Georges (CERN) ; Sterbini, Guido (CERN) ; Bartosik, Hannes (CERN) ; Triantafyllou, Natalia (CERN) ; Baudrenghien, Philippe (CERN) ; Calaga, Rama (CERN) ; Appleby, Robert (Manchester U.) ; Kostoglou, Sofia (CERN) ; Levens, Thomas (CERN) et al.
In the context of the HL-LHC upgrade, RF Crab Cavities (CCs) are one of the key components to achieve the target integrated luminosity. Due to the increased bunch intensity, the collider will operate with a large crossing angle scheme to alleviate the long-range beam-beam effect. [...]
2024 - 4 p.
- Published in : JACoW IPAC 2024 (2024) THPC63
Fulltext: PDF;
In : 15th International Particle Accelerator Conference (IPAC 2024), Nashville, TN, United States, 19 - 24 May 2024, pp.THPC63
|
|
|
7.
|
Crab Cavities for ILC
/ McIntosh, Peter (Daresbury ; Cockcroft Inst. Accel. Sci. Tech.) ; Belomestnykh, Sergey (Fermilab) ; Burt, Graeme (Lancaster U. ; Cockcroft Inst. Accel. Sci. Tech.) ; Calaga, Rama (CERN) ; De Silva, Subashini (Jefferson Lab ; Old Dominion U. (main)) ; Delayen, Jean (Old Dominion U. ; Jefferson Lab) ; Gonin, Ivan (Fermilab) ; Khabiboulline, Timergali (Fermilab) ; Lunin, Andrei (Fermilab) ; Okugi, Toshiyuki (KEK, Tsukuba) et al.
For the 14 mrad crossing angle proposed, crab cavity systems are fundamentally anticipated for the viable operation of the International Linear Collider (ILC), in order to maximise its luminosity performance. Since 2021, a specialist development team have been defining optimum crab cavity technologies which can fulfil the operational requirements for ILC, both for its baseline centre-of-mass energy of 250 GeV, but also extending those requirements out to higher beam collision intensities. [...]
FERMILAB-CONF-23-0863-SQMS-TD.-
2023 - 9 p.
- Published in : JACoW SRF 2023 (2023) 990-998
Fermilab Library Server: PDF; Fulltext: PDF; External link: Fermilab Library Server
In : 21st International Conference on Radio-Frequency Superconductivity (SRF 2023), Grand Rapids, MI, United States, 22 - 30 Jun 2023, pp.990-998
|
|
|
8.
|
RF Performance Results of RF Double Quarter Wave Resonators for LHC High Luminosity Project
/ Turaj, Katarzyna (CERN) ; Bastard, Jeremy (CERN) ; Calaga, Rama (CERN) ; Calvo, Sebastien (CERN) ; Capatina, Ofelia (CERN) ; Castilla, Alejandro (CERN ; Jefferson Lab) ; Chiodini, Marco (CERN) ; Duval, Christophe (CERN) ; Edwards, Amelia (CERN ; Lancaster U.) ; Ferreira, Leonel (CERN) et al.
The LHC High Luminosity (HL-LHC) project includes, among other key items, the installation of superconducting crab cavities in the LHC machine. The Double Quarter Wave (DQW) crab cavity will be utilised to compensate for the effects of the vertical crossing angle [...]
2023 - 7 p.
- Published in : JACoW SRF 2023 (2023) 925-928
Fulltext: PDF;
In : 21st International Conference on Radio-Frequency Superconductivity (SRF 2023), Grand Rapids, MI, United States, 22 - 30 Jun 2023, pp.925-928
|
|
|
9.
|
Advances on LHC RF Power Limitation Studies at Injection
/ Timko, Helga (CERN) ; Argyropoulos, Theodoros (CERN) ; Calaga, Rama (CERN) ; Catalán Lasheras, Nuria (CERN) ; Iliakis, Konstantinos (CERN) ; Karlsen-Bæck, Birk Emil (CERN ; Rome U.) ; Karpov, Ivan (CERN) ; Zampetakis, Michail (CERN)
The average power consumption of the main RF system during beam injection in the High-Luminosity Large Hadron Collider is expected to be close to the maximum available klystron power. Power transients due to the mismatch of the beam and the action of control loops will exceed the available power. [...]
2024 - 4 p.
- Published in : JACoW HB 2023 (2024) 567-570
Fulltext: PDF;
In : 68th ICFA Advanced Beam Dynamics workshop on high-Intensity and High-Brightness Hadron Beams (HB 2023), CERN, Geneva, Switzerland, 9 - 13 Oct 2023, pp.567-570
|
|
|
10.
|
Refining the LHC Longitudinal Impedance Model
/ Zampetakis, Michail (CERN) ; Argyropoulos, Theodoros (CERN) ; Brischetto, Ylenia (CERN) ; Calaga, Rama (CERN) ; Giacomel, Lorenzo (CERN) ; Karlsen-Bæck, Birk Emil (INFN, Rome ; Rome U. ; CERN) ; Karpov, Ivan (CERN) ; Mounet, Nicolas (CERN) ; Salvant, Benoit (CERN) ; Timko, Helga (CERN)
Modelling the longitudinal impedance for the Large Hadron Collider (LHC) has been a long-standing effort, especially in view of its High-Luminosity (HL) upgrade. The resulting impedance model is an essential input for beam dynamics studies. [...]
2024 - 4 p.
- Published in : JACoW HB 2023 (2024) 559-562
Fulltext: PDF;
In : 68th ICFA Advanced Beam Dynamics workshop on high-Intensity and High-Brightness Hadron Beams (HB 2023), CERN, Geneva, Switzerland, 9 - 13 Oct 2023, pp.559-562
|
|