CMS Hadron Forward Calorimeter Phase I Upgrade Status. (13th February 2015)

• Record Type: Journal Article
• Is Part Of: Journal of physics. Number 587(2015)
• Page Start: 012007
• Publication Date: 2015-02-13
• Subjects: Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/587/1/012007
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract: The CMS Hadronic Forward Calorimeter has undergone upgrade maintenance during the LHC Long Shutdown 1. The Hamamatsu R7525 PMTs have been replaced with Hamamatsu R7600U-200-M4 PMTs, which have thinner window glass that reduces window- hit events. The R7600 PMTs also have multi-anode readout feature to further enable discrimination of window-hits while also allowing the recovery of true signal energy. Higher quantum efficiency of the R7600 PMTs improves calorimeter resolution. The new PMTs were tested and calibrated; new PMT baseboards were designed and tested, and can be configured to readout 1, 2, or 4 anodes of the R7600. New radiation hard (100Gy) QIE front-end electronics were designed for reading out the new PMTs and include a TDC with < 800ps resolution. New back-end electronics based on the microTCA industrial standard have been tested.