MPX Detectors as LHC Luminosity Monitor

作者：Sopczak Andre^*; Ali Babar; A**ah Nedaa; Bergmann Benedikt; Bekhouche Khaled; Caforio Davide; Campbell Michael; Heijne Erik; Leroy Claude; Lipniacka Anna; Nessi Marzio; Pospisil Stanislav; Seifert Frank; Solc Jaroslav; Soueid Paul; Suk Michal; Turecek Daniel; Vykydal Zdenek

来源：IEEE Transactions on Nuclear Science, 2015, 62(6): 3225-3241.

DOI：10.1109/TNS.2015.2496316

• LHC
• luminosity
• medipix
• pixel detectors

A network of 16 Medipix-2 (MPX) silicon pixel devices was installed in the ATLAS detector cavern at CERN. It was designed to measure the composition and spectral characteristics of the radiation field in the ATLAS experiment and its surroundings. This study demonstrates that the MPX network can also be used as a self-sufficient luminosity monitoring system. The MPX detectors collect data independently of the ATLAS data-recording chain, and thus they provide independent measurements of the bunch-integrated ATLAS/LHC luminosity. In particular, the MPX detectors located close enough to the primary interaction point are used to perform van der Meer calibration scans with high precision. Results from the luminosity monitoring are presented for 2012 data taken at root s = 8 TeV proton-proton collisions. The characteristics of the LHC luminosity reduction rate are studied and the effects of beam-beam (burn-off) and beam-gas (single bunch) interactions are evaluated. The systematic variations observed in the MPX luminosity measurements are below 0.3% for one minute intervals.

• 出版日期2015-12