# LHC

2019-11-01
06:03
 Space charge and transverse instabilities at the CERN SPS and LHC / Métral, Elias (CERN) ; Amorim, David (CERN) ; Arduini, Gianluigi (CERN) ; Bartosik, Hannes (CERN) ; Benedetto, Elena (CERN) ; Burkhardt, Helmut (CERN) ; Li, Kevin (CERN) ; Oeftiger, Adrian (CERN) ; Quatraro, Diego (CERN) ; Rumolo, Giovanni (CERN) et al. At the CERN accelerator complex, it seems that only the highest energy machine in the sequence, the LHC, with space charge (SC) parameter close to one, sees the predicted beneficial effect of SC on transverse coherent instabilities. In the other circular machines of the LHC injector chain (PSB, PS and SPS), where the SC parameter is much bigger than one, SC does not seem to play a major (stabilising) role, and it is maybe the opposite in the SPS. [...] 2019 - 7 p. - Published in : 10.18429/JACoW-ICAP2018-SUPAG01 Fulltext from publisher: PDF; In : 13th International Computational Accelerator Physics Conference (ICAP 2018), Key West, FL, USA, 20 - 24 Oct 2018, pp.SUPAG01

2019-10-26
07:04
 Development of Radiation-Hard Solid-State Amplifiers for Kilogray Environments Using COTS Components / Ohmori, Chihiro (J-PARC) ; Paoluzzi, Mauro (CERN) The high-luminosity Large Hadron Collider (LHC) (HL-LHC) project is the upgrade of the LHC to increase its luminosity by a factor of 5 compared with the nominal value. The LHC injector upgrade (LIU) project aims at upgrading the LHC injector chain to reach the goal of the HL-LHC. [...] 2019 - 8 p. - Published in : IEEE Trans. Nucl. Sci. 66 (2019) 2188-2195 Fulltext: PDF;

2019-10-25
09:44
 Recent beam performance achievements with the Pb-ion beam in the SPS for LHC physics runs / Bartosik, Hannes (CERN) ; Alemany-Fernández, Reyes (CERN) ; Argyropoulos, Theodoros (CERN) ; Bohl, Thomas (CERN) ; Damerau, Heiko (CERN) ; Kain, Verena (CERN) ; Papotti, Giulia (CERN) ; Rumolo, Giovanni (CERN) ; Saá Hernández, Angela (CERN) ; Shaposhnikova, Elena (CERN) In the SPS, which is the last accelerator in the LHC ion injector chain, multiple injections of the Pb-ion beam have to be accumulated. On this injection plateau the beam suffers from considerable degradation such as emittance growth and losses. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPGW069 Fulltext from publisher: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPGW069

2019-10-25
09:43
 Reconfiguration of SPS Landau octupole circuits to minimise second order chromaticity / Bartosik, Hannes (CERN) ; Carlà, Michele (CERN) ; Cornelis, Karel (CERN) In the SPS Q20 optics presently used for LHC beams, the Landau octupole families of the SPS (LOF and LOD circuits) generate large second order chromaticity due to the relatively high dispersion at their locations. Since the induced second order chromaticity results in enhanced losses due to the large incoherent tune spread, these octupoles cannot be used for mitigating transverse instabilities for LHC beams. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPGW072 Fulltext from publisher: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPGW072

2019-10-24
06:43
 Operation and performance of the CERN Large Hadron Collider during proton Run 2 / Steerenberg, Rende (CERN) ; Albert, Markus (CERN) ; Alemany-Fernández, Reyes (CERN) ; Argyropoulos, Theodoros (CERN) ; Bravin, Enrico (CERN) ; Crockford, Guy (CERN) ; Dumont, Jean-Charles (CERN) ; Fuchsberger, Kajetan (CERN) ; Giachino, Rossano (CERN) ; Giovannozzi, Massimo (CERN) et al. Run 2 of the CERN Large Hadron Collider (LHC) started in April 2015 and was successfully completed on 10th December 2018, achieving largely all goals set in terms of luminosity production. Following the first two-year long shutdown and the re-commissioning in 2015 at 6.5 TeV, the beam performance was increased to reach a peak luminosity of more than twice the design value and a colliding beam time ratio of 50%. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPMP031 Fulltext from publisher: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPMP031

2019-10-24
06:43
 Analysis on bunch-by-bunch beam losses at 6.5 TeV in the Large Hadron Collider / Paraschou, Konstantinos (CERN ; Aristotle U., Thessaloniki) ; Iadarola, Giovanni (CERN) ; Karastathis, Nikolaos (CERN) ; Kostoglou, Sofia (Natl. Tech. U., Athens ; CERN) ; Papaphilippou, Yannis (CERN) ; Sabato, Luca (CERN) In 2018, a large fraction of the physics data taking at the Large Hadron Collider has been performed with a beam energy of 6.5 TeV, the nominal bunch spacing of 25 ns and beta functions at the high luminosity interaction points of 30 cm. In order to maximize the integrated luminosity, the crossing angles are gradually reduced as the beam intensity reduces due to luminosity burn-off. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPMP029 Fulltext from publisher: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPMP029

2019-10-24
06:43
 Second-order dispersion measurement in LHC / Keintzel, Jacqueline (TU Vienna ; CERN) ; Coello De Portugal - Martinez, Jaime (CERN) ; Dilly, Joschua (CERN) ; Fol, Elena (CERN) ; Garcia-Tabares, Ana (CERN) ; Hofer, Michael (CERN ; TU Vienna) ; Maclean, Ewen (CERN) ; Malina, Lukas (CERN) ; Persson, Tobias (CERN) ; Tomás, Rogelio (CERN) et al. The quadratic dependence of the orbit on the relative momentum ofset, also known as second-order dispersion, is analysed for the first time for the LHC. In this paper, the measurement and analysis procedure are described. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPMP027 Fulltext from publisher: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPMP027

2019-10-24
06:43
 Moving long-range beam-beam encounters in heavy-ion colliders / Jebramcik, Marc (CERN ; Goethe U., Frankfurt (main)) ; Jowett, John (CERN) Asymmetric ion beam collisions like proton-lead in the LHC or gold-deuteron in RHIC have become major components of heavy-ion physics programmes. The injection and ramp of two different ion species with the same magnetic rigidity and consequently unequal revolution frequencies generate moving long-range beam-beam encounters in the interaction regions of the collider. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPMP025 Preprint: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPMP025

2019-10-24
06:43
 Prospects for future asymmetric collisions in the LHC / Jebramcik, Marc (CERN ; Goethe U., Frankfurt (main)) ; Jowett, John (CERN) The proton-lead runs of the LHC in 2012, 2013 and 2016 provided luminosity far beyond expectations in a diversity of operating conditions and led to important new results in high-density QCD. This has permitted the scope of the future physics programme to be expanded in a recent review. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPMP024 Preprint: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPMP024

2019-10-23
06:55
 Collimation of partially stripped ion beams in the LHC / Abramov, Andrey (JAI, UK ; Royal Holloway, U. of London ; CERN) ; Bruce, Roderik (CERN) ; Fuster-Martínez, Nuria (CERN) ; Gorzawski, Arkadiusz (CERN ; U. Malta) ; Krasny, Mieczyslaw (CERN) ; Molson, James (CERN) ; Nevay, Laurence (JAI, UK ; Royal Holloway, U. of London ; CERN) ; Redaelli, Stefano (CERN) ; Schaumann, Michaela (CERN) In the scope of the Physics Beyond Colliders studies, the Gamma Factory initiative proposes the use of partially stripped ions as a driver of a new type, high intensity photon source in CERN’s Large Hadron Collider (LHC). In 2018, the LHC accelerated and stored partially stripped $^{208}$Pb$^{81+}$ ions for the first time. [...] 2019 - 4 p. - Published in : 10.18429/JACoW-IPAC2019-MOPRB058 Fulltext from publisher: PDF; In : 10th International Particle Accelerator Conference, Melbourne, Australia, 19 - 24 May 2019, pp.MOPRB058