Sensitivity tests of BLM_S chamber in PSB dump (Detector for very high radiation areas of LHC ) 11/5/2006 AB/BI D.Kramer
What is BLM_S Low sensitivity BLM pumped to approx. 10-5 torr Based on Secondary Electron Emission from Ti electrode Placed mainly in the Collimation areas, close to IPs, LHC Dump etc… 11/5/2006 APC meeting
Interior of Secondary Emission Beam Loss Monitor 11/5/2006 APC meeting
Geant4 Simulation Results Secondary Emission Yield 0 Geant4 Simulation Results Secondary Emission Yield 0.057 e-/primary @ 1.3GeV
Geant4 Simulation Results SEY vs. Ti Signal electrode thickness Beam line SEM screens BLM_S
Installation in the PSB dump line Screen BLM_S ACEM Rad Hard camera 11/5/2006 APC meeting
2005 PSB measurements 11/5/2006 APC meeting
Comparison with results from PSI 250MeV continuous proton beam 11/5/2006 APC meeting
Modified SEM tested in PSI
2006 Measurements in PSB dump Modified BLMS installed on the movable stage 19/4 1st data taken 4/5 with up to 250e10 protons/bunch (AD user) maximum intensity allowed by the BLM system Access due to HV contact 10/5 11/5/2006 APC meeting
Linearity of the SEM response in 2006 11/5/2006 APC meeting
Simultaneous measurement with SEM and ACEM (PS BLM) equivalent to ~ 1e19 MIPs/s
Quench and Damage Levels BLMS* & BLMC Quench level and observation range 450 GeV 7 TeV Damage levels Dynamic Arc: 108 Collimator: 1013 BLMS*: 3.2E13 protonen (nominal SPS injection) lost in about 10E-5 seconds. Special & Collimator1 turn Arc 2.5 ms 11/5/2006 APC meeting
Summary SEY from the first measurements in 2006: (5 ± 0.3)% Good agreement with 5.7% from Geant4 No more problems with linearity Sufficient time response HV scan to be done (we need ~2h beam time) 11/5/2006 APC meeting