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This content will become publicly available on January 1, 2026

Title: Recent upgrades to the calibration system of the CMS HCAL
The irradiation of the CMS Hadron Calorimeter (HCAL) subdetectors results in decreased signal output from the active materials as well as increased noise in the photodetectors used to read out the system. The HCAL has a dedicated calibration system used to monitor and correct for these effects and to help synchronise the timing of the subdetectors. The calibration system is described with a focus on the upgrades to the laser system, which has undergone significant changes since the end of Run 2 of the LHC in 2018. A new solid state laser has been installed and commissioned, and the optical setup for light distribution has been simplified. An upgrade to the laser trigger board has reduced the laser trigger jitter by an order of magnitude. A new system has also been developed to fire the laser, based on existing HCAL electronics. Future improvements to the system are also presented, including ongoing work on extending the system to include remote monitoring capabilities.  more » « less
Award ID(s):
2209460
PAR ID:
10590442
Author(s) / Creator(s):
;
Editor(s):
Chujo, T; Ootani, W
Publisher / Repository:
EPJ Web Conf.
Date Published:
Journal Name:
EPJ Web of Conferences
Volume:
320
ISSN:
2100-014X
Page Range / eLocation ID:
00042
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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