Beam Test of a SiPM-on-Tile ZDC Prototype with 5.3 GeV Positrons at Jefferson Laboratory

Abstract

We report on a beam test of a Silicon Photo-Multiplier (SiPM)-on-tile Zero Degree Calorimeter (ZDC) prototype developed for the future Electron-Ion Collider (EIC). The detector implements the staggered scintillator-tile geometry envisioned for the final detector and includes 370 instrumented channels, corresponding to O(10%) of the full ZDC. The detector was tested using a 5.3 GeV positron beam at Jefferson Laboratory. We measure the energy response, shower shape, and spatial reconstruction performance of the detector and compare these results with simulation. These studies provide key input for the optimization of the final ePIC ZDC design.