AstroPix: CMOS pixels in space

TL;DR

AstroPix introduces monolithic CMOS active pixel sensors for space gamma-ray telescopes, aiming to improve resolution and noise performance over traditional silicon strip detectors.

Contribution

This work develops and tests AstroPix, a novel CMOS-based detector technology for gamma-ray astronomy, offering simplified fabrication and enhanced detection capabilities.

Findings

AstroPix demonstrates comparable resolution to silicon strip detectors.

The CMOS sensors show reduced noise levels.

Prototype testing indicates suitability for future space telescopes.

Abstract

Space-based gamma-ray telescopes such as the Fermi Large Area Telescope have used single sided silicon strip detectors to measure the position of charged particles produced by incident gamma rays with high resolution. At energies in the Compton regime and below, two dimensional position information within a single detector is required. Double sided silicon strip detectors are one option; however, this technology is difficult to fabricate and large arrays are susceptible to noise. This work outlines the development and implementation of monolithic CMOS active pixel silicon sensors, AstroPix, for use in future gamma-ray telescopes. Based upon detectors designed using the HVCMOS process at the Karlsruhe Institute of Technology, AstroPix has the potential to maintain the high energy and angular resolution required of a medium-energy gamma-ray telescope while reducing noise with the dual detection-and-readout capabilities of a CMOS chip. The status of AstroPix development and testing as well as outlook for application in future telescopes is presented.