Performance of the AstroPix Prototype Module for the Barrel Imaging Calorimeter at the ePIC Detector and in Space-Based Payloads

Bobae Kim; Regina Caputo; Manoj Jadhav; Sylvester Joosten; Adrien Laviron; Richard Leys; Jessica Metcalfe; Nicolas Striebig; Daniel Violette; Maria Żurek

doi:10.22323/1.513.0031

arXiv · 2511.05639

Performance of the AstroPix Prototype Module for the Barrel Imaging Calorimeter at the ePIC Detector and in Space-Based Payloads

Bobae Kim·Regina Caputo·Manoj Jadhav·Sylvester Joosten·Adrien Laviron·Richard Leys·Jessica Metcalfe·Nicolas Striebig·Daniel Violette·Maria Żurek

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Abstract

AstroPix is a high-voltage CMOS (HV-CMOS) monolithic active pixel sensor originally developed to enable precision gamma-ray imaging and spectroscopy in the medium-energy regime (approximately 100 keV-100 MeV) based on the groundwork laid by ATLASpix and MuPix. It features a 500 um pixel pitch, in-pixel amplification and digitization, and low power consumption (around 3-4 mW/cm^2), making it scalable for large-area, multilayer telescope detector planes. The detectors have a designed dynamic range of 25 keV to 700 keV. With these features, AstroPix meets the requirements of future space-based high-energy telescopes and the imaging layers of the Barrel Imaging Calorimeter (BIC) in the Electron-Proton/Ion Collider (ePIC) detector at the future Electron-Ion Collider (EIC). For the space-based payload, AstroPix is being integrated into sounding rocket and balloon payloads to demonstrate the technical readiness of the devices. For BIC, AstroPix-based imaging layers interleaved within the lead/scintillating-fiber (Pb/SciFi) sampling calorimeter provide granular shower imaging, enabling key performance features such as electron/pion or gamma/neutral-pion separation. As part of the ongoing detector R&D efforts, we have been testing various AstroPix v3 configurations: the single chip, a quad-chip assembly, a three-layer stack of quad chips, and a nine-chip module that represents the smallest prototype unit of the BIC imaging layer. This presentation will highlight recent performance test results from these AstroPix detector configurations.

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BibTeX RIS

Bobae Kim, Regina Caputo, Manoj Jadhav, Sylvester Joosten, Adrien Laviron, Richard Leys, Jessica Metcalfe, Nicolas Striebig, Daniel Violette, Maria Żurek. 2025-11-07. Performance of the AstroPix Prototype Module for the Barrel Imaging Calorimeter at the ePIC Detector and in Space-Based Payloads. https://doi.org/10.22323/1.513.0031

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