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arXiv · 2410.10617

Status and performance of the ALICE Fast Interaction Trigger

Yury Melikyan
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Abstract

The ALICE apparatus at CERN has undergone significant upgrade during the LHC's Long Shutdown 2 to increase the experiment's rate capability and measurement precision for Run 3 and Run 4. One of the key detectors newly introduced to the experiment is the Fast Interaction Trigger (FIT). Featuring minimal dead time, FIT provides a comprehensive trigger menu, including the minimum bias trigger with an efficiency exceeding 90 percent in proton-proton collisions. It also provides centrality, event plane, and background measurement capabilities. Precision of the collision time measurements performed by FIT reached remarkable values of 17 ps (sigma) in proton-proton collisions and 4.4 ps (sigma) in Pb-Pb collisions. This paper details FIT's design, performance, and the technical novelties made to meet the stringent environmental requirements of ALICE.

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Yury Melikyan. 2024-10-14. Status and performance of the ALICE Fast Interaction Trigger. https://arxiv.org/abs/2410.10617

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