Photodesorption studies at cryogenic temperatures for accelerator applications

by Vincent Baglin (LHC Division)

Thursday 15 Jun 2000, 14:15 → 16:00 Europe/Zurich

CERN

The proton beams circulating inside an LHC vacuum chamber will induce so-called dynamic effects leading, for example, to a pressure rise and thus a reduction of the beam lifetime. After a brief introduction describing dynamic effects, such as ion induced vacuum instability and beam induced electron multipacting, the presentation will focus on photon induced molecular desorption in the cryogenic regions of the machine. The 2 m long UHV/cyogenic instrument, COLDEX, designed to simulate the LHC arc vacuum system, has been mounted either on an external beam line of EPA or in the EPA ring. A summary of the studies performed over the last two years and their implications to the LHC design will be presented.