CMS Document 3352-v1
HCAL Barrel (HB) and Endcap (HE) Gains
- HB and HE use scintilator tiles as the active detector element, sandwiched within 5cm slabs of brass absorber. The light from the 16 tiles forming a calorimeter cell is summed by bringing the appropriate tile fibers to the same pixel of the HPD photodetector via a fiber jungle called the Optical Decoder Unit (ODU). The HPD gain is about 2000 at the operating HV of ~7000V, giving a signal of ~0.3fC/photoelectron, or ~0.2GeV/fC. More precisely, HB = 0.19 ± 0.03 GeV/fC, HE = 0.23 ± 0.04 GeV/fC, with distributions. The sensitivity of the HBHE QIE electronics is nominally1 fC/count, with calibration corrections, more precisely 0.92 ± 0.02 (linearized QIE cnts/fC).
- Related Documents:
- CMS-doc-3351: HCAL Forward (HF) Gains
- Referenced by: