The CMS Fast Beam Condition Monitor for HL-LHC

• DOI: 10.48550/arxiv.2402.03971
• Publication Date: 2024-02-06
• Authors: G. Auzinger; H. Bakhshiansohi; Anne Dabrowski; A. G. Delannoy; A. Dierlamm; M. Dragicevic; A. Gholami; G. Gómez; M. Guthoff; M. Haranko; A. Homna; Maksim Jenihhin; J. Kaplon; O. Karacheban; B. Korcsmáros; W. H. Liu; A. Lokhovitskiy; R. Loos; S. Mallows; J. Michel; V. Myronenko; G. Pásżtor; M. Pari; J. Schwandt; M. Sedghi; Alexey Shevelev; Konstantin Shibin; Georg Steinbrueck; David Stickland; Balázs Újvári; G. J. Wegrzyn

The high-luminosity upgrade of the LHC brings unprecedented requirements for real-time and precision bunch-by-bunch online luminosity measurement beam-induced background monitoring. A key component CMS Beam Radiation, Instrumentation Luminosity system is a stand-alone luminometer, Fast Condition Monitor (FBCM), which fully independent from central trigger data acquisition services able to operate at all times with triggerless readout. FBCM utilizes dedicated front-end application-specific integrated circuit (ASIC) amplify signals CO$_2$-cooled silicon-pad sensors timing resolution few nanoseconds, enables background. uses modular design two half-disks twelve modules each end CMS, four service placed close outer edge reduce radiation-induced aging. electronics adapts several components Tracker power, control read-out functionalities. FBCM23 ASIC contains six channels adjustable shaping time optimize noise regards sensor leakage current. Each channel outputs single binary high-speed asynchronous signal carrying time-of-arrival time-over-threshold information. chip output digitized, encoded sent via radiation-hard gigabit transceiver an optical link back-end analysis. This paper reports on updated detector ongoing testing program.