FemtoDAQ: A Low-Cost Digitizer for SiPM-Based Detector Studies and its Application to the HAWC Detector Upgrade

TL;DR

The FemtoDAQ system is a low-cost, versatile data acquisition device designed for SiPM-based detectors, demonstrated in applications including the HAWC gamma-ray observatory upgrade, enabling efficient testing and deployment in challenging environments.

Contribution

This paper introduces the FemtoDAQ, a compact, low-cost digitizer system for SiPMs, and demonstrates its application in the HAWC detector upgrade for gamma-ray astronomy.

Findings

FemtoDAQ effectively characterizes SiPM signals.

It supports powering, biasing, and digitization in one unit.

Application to HAWC shows practical utility.

Abstract

The FemtoDAQ is a low-cost two channel data acquisition system which we have used to investigate the signal characteristics of silicon photomultipliers (SiPMs) coupled to fast scintillators. The FemtoDAQ system can also be used to instrument low cost moderate performance passive detectors, and is suitable for use in harsh environments (e.g., high altitude). The FemtoDAQ is being used as a SiPM test bench for the High Altitude Water Cherenkov (HAWC) Observatory, a TeV gamma ray detector located 4100 m above sea level. Planned upgrades to the HAWC array can benefit greatly from SiPMs, a robust, low-voltage, low-cost alternative to traditional vacuum photomultipliers. The FemtoDAQ is used to power the SiPM detector front end, bias the SiPM, and digitize the photosensor output in a single compact unit.