Design and Performance Simulation of the Electromagnetic Calorimeter at EicC

TL;DR

This paper details the optimized design and simulation of the EicC electromagnetic calorimeter, demonstrating high energy resolution and effective particle discrimination crucial for electron-ion collision experiments.

Contribution

It introduces a novel segmented ECAL design with tailored materials and geometries optimized via Geant4 simulations for the EicC detector.

Findings

Achieves 2%/√E energy resolution with pCsI crystals.

Achieves 5%/√E energy resolution with Shashlik modules.

Demonstrates effective electron-pion discrimination.

Abstract

The electromagnetic calorimeter (ECAL) is a key detector component for precise electron and photon measurements in electron-ion collision experiments. At the Electron-Ion Collider in China (EicC), high-performance calorimetry is essential for exploring the internal structure of nucleons and studying the dynamics of quarks and gluons within quantum chromodynamics (QCD). This paper presents the optimized design and performance simulation of the EicC ECAL system. The ECAL consists of three specialized sections tailored to distinct detection environments: (1) an electron-Endcap employing high-resolution pure Cesium Iodide (pCsI) crystals, (2) a central barrel, and (3) an ion-Endcap, both adopting a cost-effective Shashlik-style sampling calorimeter with improved light yield. Each segment's geometry and material composition have been systematically optimized through Geant4 simulations to achieve excellent energy and position resolutions as well as strong electron-pion discrimination. The simulated performance indicates that the ECAL can achieve energy resolutions of 2 percent divided by sqrt(E) for pCsI crystals and 5 percent divided by sqrt(E) for Shashlik modules, meeting the design goals of the EicC detector.