Precision Timing with the CMS MIP detector

TL;DR

The paper discusses the development and testing of a new timing detector for the CMS experiment at CERN, aiming to improve particle timing resolution to handle high pile-up conditions at the HL-LHC.

Contribution

It introduces a novel timing layer with 30 ps resolution using LYSO:Ce crystals and LGADs, and reports on the current status and R&D efforts including test beam results.

Findings

Achieved 30 ps timing resolution in prototypes

Successful integration of LYSO:Ce crystals and LGAD sensors

Demonstrated detector performance in test beam experiments

Abstract

The Compact Muon Solenoid (CMS) detector at the CERN Large Hadron Collider (LHC) is undergoing an extensive Phase II upgrade program to prepare for the challenging conditions of the High-Luminosity LHC (HL-LHC). A new timing layer is designed to measure minimum ionizing particles (MIPs) with a time resolution of 30 ps and a hermetic coverage up to a pseudo-rapidity of $|\eta|$ = 3. This MIP Timing Detector(MTD) will consist of a central barrel region based on LYSO:Ce crystals read out with SiPMs and two end-caps instrumented with radiation-tolerant Low Gain Avalanche Diodes (LGADs). The precision time information from the MTD will reduce the effects of the high levels of pile-up expected at the HL-LHC, and will bring new and unique capabilities to the CMS detector. We present the current status and ongoing R&D of the MTD, including recent test beam results.