The performance of SiPM-based gamma-ray detector (GRD) of GECAM-C

TL;DR

This paper evaluates the design, ground testing, and in-flight performance of SiPM-based gamma-ray detectors on GECAM-C, demonstrating their readiness for scientific observations of gamma-ray transients.

Contribution

It provides the first comprehensive assessment of GECAM-C's SiPM-based detectors, including design details and performance comparison with GECAM-B.

Findings

GECAM-C GRDs perform as expected in-flight

SiPM performance is comparable between GECAM-C and GECAM-B

Detectors are ready for scientific gamma-ray transient observations

Abstract

As a new member of GECAM mission, the GECAM-C (also called High Energy Burst Searcher, HEBS) is a gamma-ray all-sky monitor onboard SATech-01 satellite, which was launched on July 27th, 2022 to detect gamma-ray transients from 6 keV to 6 MeV, such as Gamma-Ray Bursts (GRBs), high energy counterpart of Gravitational Waves (GWs) and Fast Radio Bursts (FRBs), and Soft Gamma-ray Repeaters (SGRs). Together with GECAM-A and GECAM-B launched in December 2020, GECAM-C will greatly improve the monitoring coverage, localization, as well as temporal and spectral measurements of gamma-ray transients. GECAM-C employs 12 SiPM-based Gamma-Ray Detectors (GRDs) to detect gamma-ray transients . In this paper, we firstly give a brief description of the design of GECAM-C GRDs, and then focus on the on-ground tests and in-flight performance of GRDs. We also did the comparison study of the SiPM in-flight performance between GECAM-C and GECAM-B. The results show GECAM-C GRD works as expected and is ready to make scientific observations.