Title :
Vacuum calculations for the LHC experimental beam chambers
Author :
Collins, I. ; Knaster, J.R. ; Lepeule, P. ; Rossi, A. ; Veness, R.
Author_Institution :
CERN, Geneva, Switzerland
Abstract :
The vacuum stability is studied for the LHC experimental beam vacuum chambers of ALICE, ATLAS, and CMS. The present baseline design includes sputtered non-evaporable getter (NEG) coating over the whole chamber inner surface providing distributed pumping and an antimultipactor coating. The data are presented for the dominant gas species (H2, CH4, CO and CO2) in a baked system. It results that the distributed pumping is necessary for vacuum stability of CO. Lumped pumping with sputter ion pumps (SIP) is also indispensable for the stability of CH4. The operational constraints with NEG technology are described
Keywords :
beam handling equipment; colliding beam accelerators; getters; proton accelerators; synchrotrons; vacuum pumps; ALICE; ATLAS; CMS; CO; CO2; H2; LHC experimental beam chambers; Large Hadron Collider; antimultipactor coating; baseline design; chamber inner surface; distributed pumping; methane; operational constraints; sputtered nonevaporable getter; vacuum calculations; vacuum stability; Coatings; Collision mitigation; Electron accelerators; Electron emission; Gettering; Large Hadron Collider; Laser excitation; Particle beams; Space technology; Stability;
Conference_Titel :
Particle Accelerator Conference, 2001. PAC 2001. Proceedings of the 2001
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-7191-7
DOI :
10.1109/PAC.2001.988035
