0000000000656111
AUTHOR
A. Rummler
Beam test results of IHEP-NDL Low Gain Avalanche Detectors(LGAD)
A High-Granularity Timing Detector (HGTD) is proposed based on the Low-Gain Avalanche Detector (LGAD) for the ATLAS experiment to satisfy the time resolution requirement for the up-coming High Luminosity at LHC (HL-LHC). We report on beam test results for two proto-types LGADs (BV60 and BV170) developed for the HGTD. Such modules were manufactured by the Institute of High Energy Physics (IHEP) of Chinese Academy of Sciences (CAS) collaborated with Novel Device Laboratory (NDL) of the Beijing Normal University. The beam tests were performed with 5 GeV electron beam at DESY. The timing performance of the LGADs was compared to a trigger counter consisting of a quartz bar coupled to a SiPM read…
Performance of the upgraded PreProcessor of the ATLAS Level-1 Calorimeter Trigger
The PreProcessor of the ATLAS Level-1 Calorimeter Trigger prepares the analogue trigger signals sent from the ATLAS calorimeters by digitising, synchronising, and calibrating them to reconstruct transverse energy deposits, which are then used in further processing to identify event features. During the first long shutdown of the LHC from 2013 to 2014, the central components of the PreProcessor, the Multichip Modules, were replaced by upgraded versions that feature modern ADC and FPGA technology to ensure optimal performance in the high pile-up environment of LHC Run 2. This paper describes the features of the newMultichip Modules along with the improvements to the signal processing achieved.
Observation and Measurement of Forward Proton Scattering in Association with Lepton Pairs Produced via the Photon Fusion Mechanism at ATLAS
The observation of forward proton scattering in association with lepton pairs (eþe− þ p or μþμ− þ p) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer, while the leptons are reconstructed by the central ATLAS detector. Proton-proton collision data recorded in 2017 at a center-of-mass energy of ffiffiffi s p ¼ 13 TeV are analyzed, corresponding to an integrated luminosity of 14.6 fb−1. A total of 57 (123) candidates in the ee þ p (μμ þ p) final state are selected, allowing the background-only hypothesis to be rejected with a significance exceeding 5 standard deviations in each channel. Proton-tagging techniques are introduced f…