Author: Burkhardt, H.
Paper Title Page
MOPMF042 Crab Cavity Failures Combined with a Loss of the Beam-Beam Kick in the High Luminosity LHC 192

• B. Lindstrom, H. Burkhardt, V.K.B. Olsen, A. Santamaría García, K.N. Sjobak, M. Valette, D. Wollmann
CERN, Geneva, Switzerland

Crab cavities are an essential component of the High Luminosity LHC (HL-LHC) project. In case of a failure they can create large transverse kicks on the beam within tens of microseconds and, therefore, require a fast extraction of the circulating beam. In this paper, the effects of different crab cavity failures in combination with the missing beam-beam kick following the dump of only one LHC beam are presented and consequences for the interlocking strategy of crab cavities are discussed.
Work supported by the High Luminosity LHC project.

DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF042
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMF051 LHC Operational Scenarios During 2017 Run 220

• B. Salvachua, M. Albert, R. Alemany-Fernández, T. Argyropoulos, E. Bravin, H. Burkhardt, G.E. Crockford, JCD. Dumont, S.D. Fartoukh, K. Fuchsberger, R. Giachino, M. Giovannozzi, G.H. Hemelsoet, W. Höfle, J.M. Jowett, Y. Le Borgne, D. Nisbet, M. Pojer, L. Ponce, S. Redaelli, M. Solfaroli, R. Suykerbuyk, D.J. Walsh, J. Wenninger, M. Zerlauth
CERN, Geneva, Switzerland

During 2017, the Large Hadron Collider LHC delivered luminosity for different physics configuration in addtion to the nominal 6.5 TeV proton-proton run. About 18.5 days were dedicated to commission and to deliver special physics to the experiments. Condifurations with large beta-star of 19 m and 24 m were prepared for luminosity calibration with Van de Meer scans. A proton-proton run at 2.51 TeV took place during the last weeks of November to provide reference data for the heavy ion (Pb-Pb, p-Pb) collisions at the same equivalent nucleon energy . A very short (0.5 days) but effective ion run was scheduled where the LHC saw the first Xe beams collissions and delivered around 3 ub-1 to ATLAS and CMS. The run ended with a low event pile-up run at 6.5TeV. This contribution summarizes the operational aspects and delivered targets for the different configurations.
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF051
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMF085 Beam-gas Background Characterization in the FCC-ee IR 322

• M. Boscolo, O.R. Blanco-García
INFN/LNF, Frascati (Roma), Italy
• H. Burkhardt, R. Kersevan, M. Lueckhof
CERN, Geneva, Switzerland
• F. Collamati
INFN-Roma1, Rome, Italy

The MDISim toolkit is used to evaluate and characterize the beam-gas induced background in the FCC-ee Interaction Region. MDISim allows a full characterization of this beam background source with the locations where the beam-gas scattering occurs as well as the loss points, as a function of different vacuum conditions and composition, for the nominal optics and parameters. Detailed pressure distribution profiles have been obtained running coupled synchrotron radiation and molecular flow montecarlo codes, as an input to the GEANT4 calculations. The particles hitting the pipe in the IR can be tracked in the detectors with a full Geant-4 simulation. Semi-analytic estimates for the expected rates and lifetime are also performed.
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF085
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPML012 Special Collimation System Configuration for the LHC High-Beta Runs 418

• H. Garcia Morales
Royal Holloway, University of London, Surrey, United Kingdom
• R. Bruce, H. Burkhardt, M. Deile, S. Jakobsen, A. Mereghetti, S. Redaelli
CERN, Geneva, Switzerland

Special LHC high-beta optics is required for the forward physics program of TOTEM and ATLAS-ALFA. In this configuration, the beam is de-squeezed (the \beta-function at the collision point is increased) in order to minimize the divergence for measurements at very small scattering angles. In these low beam intensity runs, it is important to place the Roman Pots (RPs) as close as possible to the beam, which demands special collimator settings. During Run I, a significant amount of background was observed in the forward detectors due to particles outscattered from the primary collimator. During Run II, a different collimation configuration was used where a tungsten collimator was used as primary collimator instead of the usual one made of carbon. Using this configuration, a significant reduction of the background at the RPs was observed. In this paper we present a description of the new collimator configuration and the results obtained during the high-beta run carried out in 2016.
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPML012
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)