Modular RICH detector development for the future Electron Ion Collider experiment

Abstract

Excellent particle identification is an essential requirement for the future Electron Ion Collider (EIC) experiment. Particle identification (PID) of the final state hadrons in semi-inclusive deep inelastic scattering allows the measurement of flavor-dependent gluon and quark distributions inside nucleons and nuclei. The EIC PID Consortium (eRD14 Collaboration) was formed in 2015 for identifying and developing PID detectors using ring imaging Cherenkov and ultra-fast time-of-flight techniques for the EIC experiments with broad kinematics coverage. To meet the challenge of limited space in the electron end-cap of EIC experiments, a compact modular ring imaging Cherenkov (mRICH) detector has been developed that provides K/πseparation over a momentum coverage of 2 GeV/cto 10 GeV/c, and an e/πseparation up to 2.5 GeV/cor more. The mRICH detector consists of an aerogel block, a Fresnel lens, photosensor plane and flat mirrors enclosing the sides of the space between the lens and photosensors. The first prototype of this detector was successfully tested at Fermi National Accelerator laboratory in April 2016 for verifying the detector principles. This was followed by a second prototype test in 2018 at FNAL with much improved optical design and photosensor integration, which allowed adaptation of different readout options. In September 2021, the third beam-test was carried at Jefferson Laboratory (JLAB) with the goal of testing the mRICH performance with a precision tracking capability.