Barrel Imaging Electromagnetic Calorimeter for the ePIC Experiment at the Electron-Ion Collider*

The Electron-Ion Collider (EIC) is envisioned as an experimental facility to investigate gluons in nucleons and nuclei, offering insights into their structure and interactions. The EIC Project includes a single general-purpose detector: The ePIC Detector. The unique physics goals at the EIC necessitate specific design considerations for the barrel electromagnetic calorimeter (ECal) in ePIC. Precise measurements of electron energy and shower profiles are crucial for effectively distinguishing electrons from background pions in Deep Inelastic Scattering processes at high Q² within the barrel ECal. Furthermore, the calorimeter must accurately gauge the energy and coordinates of photons from processes such as Deeply Virtual Compton Scattering, while identifying photon pairs from π⁰ decays.

In this presentation, I will discuss the design of the barrel ECal of ePIC. Our hybrid approach combines scintillating fibers embedded in lead with imaging calorimetry based on AstroPix sensors, a low-power monolithic active pixel sensor. Through comprehensive simulations, we have tested the calorimeter design against the key requirements outlined in the EIC Yellow Report. I will focus on the anticipated performance of the calorimeter, detailing progress in design and prototyping. Additionally, I will provide insights into the development timeline and collaborative efforts involved in this endeavor.