Optical Characterization of Fresnel Lens and Aerogel of mRICH Detector for Electron Ion Collider Experiments*

The recent announcement of the construction of an Electron Ion Collider (EIC) at Brookhaven National Laboratory by the U.S. Department of Energy makes the long-sought experimental effort to explore the structure and properties of proton and nuclei in unprecedented precision and broad kinematic coverage a reality. Particle identification (PID) of the final state hadrons is an essential requirement for EIC. In order to meet the challenge of the limited space in the electron endcap in EIC experiments, a compact, projective, and modular ring imaging Cherenkov (mRICH) detector is proposed for K/π separation from 3 up to 10 GeV/c. The mRICH detector consists of an Aerogel radiator block, a Fresnel lens, a four-sided mirror-wall and a photosensor plane. An optical characterization setup is currently being developed at Georgia State University for measuring the uniformity and photon transmission of the Fresnel lens and the Aerogel block. In this poster, we will present the design, construction, and testing of the setup. A GEANT4-based simulation study of Fresnel lens and Aerogel properties will also be presented.