High resolution digitization system for the CROSS experiment

TL;DR

This paper presents a high-resolution, scalable digitization system for the CROSS experiment, enabling precise data acquisition for neutrinoless double beta decay searches with customizable filtering and efficient data transfer.

Contribution

It introduces a custom analog-to-digital system with FPGA-based synchronization and scalability for bolometric experiments, tailored for fast scintillating bolometers.

Findings

Achieved 21-bit resolution at 5 ksps per channel.

Supported up to 96 channels with FPGA scalability.

Demonstrated effective anti-aliasing filter control.

Abstract

The signal digitization for CROSS, a bolometric experiment for the search of neutrinoless double beta decay at LSC - Canfranc Underground Laboratory, will be based on a custom solution comprised of an analog-to-digital board interfaced to an Altera Cyclone V FPGA module. Each analog-to-digital board hosts 12 channels that allow data digitization up to 25 ksps per channel and an effective resolution of 21 bits at the typical sample rate required by the experiment (5 ksps). The board also allows to digitally select the cut-off frequency of the anti-aliasing filter with 10 bit resolution from 24 Hz up to 2.5 kHz, as required by fast scintillating bolometers. The FPGA is responsible for the synchronization of the analog-to-digital boards and for the data transfer to the storage, using UDP protocol on a standard Ethernet interface. Each FPGA can manage the data coming from 8 boards (96 channels), allowing an excellent scalability. In this contribution we will present a complete overview of the system, and a detailed characterization of the system performance.