30 likes | 279 Views
CMS: ECAL Barrel APDs. Avalanche Photodiodes Hamamatsu S8148 reverse structure Radiation-hard for 10 years LHC operation in the ECAL barrel Active area 5x5 mm 2 , 2 APDs per crystal (122400 in total) Mean gain of each pair = 50, QE ~ 75%
E N D
CMS: ECAL Barrel APDs • Avalanche Photodiodes • Hamamatsu S8148 reverse structure • Radiation-hard for 10 years LHC operation in the ECAL barrel • Active area 5x5 mm2, 2 APDs per crystal (122400 in total) • Mean gain of each pair = 50, QE ~ 75% • Expected energy resolution of 0.5% at 120GeV achieved in beam tests
CMS: ECAL Endcap VPTs • Vacuum Phototriodes • Research Institute Electron PMT188 • Single-stage PMT • Gain ~10 in 4T axial field, QE ~ 20% • Mesh anode, 10m pitch • Radiation-hard for use at the higher dose rates in the endcaps. • Relative response v angle in B field • VPTs function well over 6-26 range needed in CMS • Response v B field at 15 • Little reduction in gain for field > 1T