Characterization and performance of the ASIC (CITIROC) front-end of the ASTRI camera

TL;DR

This paper characterizes the CITIROC ASIC front-end for the ASTRI telescope camera, demonstrating its linear response and suitability for the camera's requirements through various tests with SiPMs.

Contribution

It provides detailed measurements of CITIROC's trigger linearity, efficiency, and response under different conditions, tailored for the ASTRI SST-2M focal plane.

Findings

CITIROC output varies linearly with input pulse amplitude

The chip meets the linearity and efficiency requirements for ASTRI SST-2M

Suitable for use in the ASTRI camera system

Abstract

The Cherenkov Imaging Telescope Integrated Read Out Chip, CITIROC, is a chip adopted as the front-end of the camera at the focal plane of the imaging Cherenkov ASTRI dual-mirror small size telescope (ASTRI SST-2M) prototype. This paper presents the results of the measurements performed to characterize CITIROC tailored for the ASTRI SST-2M focal plane requirements. In particular, we investigated the trigger linearity and efficiency, as a function of the pulse amplitude. Moreover, we tested its response by performing a set of measurements using a silicon photomultiplier (SiPM) in dark conditions and under light pulse illumination. The CITIROC output signal is found to vary linearly as a function of the input pulse amplitude. Our results show that it is suitable for the ASTRI SST-2M camera.