Simulations of a hadron endcap Forward Calorimeter System at EIC*

A preliminary design of hadron endcap Forward Calorimeter System (FCS) based on a binary configuration was proposed in the EIC Yellow Report. We modeled the Geant simulations of various electromagnetic and hadronic calorimeters to quantify and optimize the forward (1 < η < 3.5) calorimeter system in measurement of jet energy. In this study, we employed Geant4.10 based model to reproduce ZEUS detector beam test data following both prototypes of Pb/Sc and DU/Sc configuration. Differential cross-checks on energy resolution, mean deposited energy ratio for hardrons and electrons at both high and low incident energy provided a good validation on analysis code. We found the design of EIC Hadron Endcap Calorimeter configuration using W/ScFi as ECal and Fe/Sc as HCal with the best optimization under the constraints of materials and available space. Instrumental variations such as sampling fraction, dead layers, interaction length, mean deposite energy ratio and birks coefficience were investigated to optimize the performance of the model. The results indicated W/ScFi and Fe/Sc configurations to be an viable compact FCS design that meets the EIC requirements in the hadron forward direction. A full scale prototype is needed to validate the simulation results.