A Muti-channel Distributed DAQ for n-TPC

TL;DR

This paper presents a multi-channel distributed data acquisition system for the n-TPC neutron spectrometer, enabling flexible, triggerless, high-speed data collection from 704 channels to optimize detector performance.

Contribution

It introduces a novel distributed DAQ system with high sampling rate and flexible operation supporting the n-TPC's application in various experimental conditions.

Findings

Achieved over 25 Ms/s sampling rate per channel.

Supported triggerless, multi-channel data acquisition for the n-TPC.

Enhanced detector parameter optimization and operational flexibility.

Abstract

A new fast neutron spectrometer named n-TPC has been designed by LPRI (Key Laboratory of Particle & Radiation Imaging, Ministry of Education) at Tsinghua University. The neutron energy spectrum can be calculated from the recoil angle and energy of the recoil proton detected by a 704-pad GEM-TPC. In beam tests at IHIP (Institute of Heavy Ion Physics, Peking University) in 2014, n-TPC performed better than 6 percents at 6MeV energy resolution and 0.5 percents detection efficiency. To find the best working parameters (the component and proportion of the gas, the high voltage between each GEM layer, etc.) of the n-TPC and support its application in various conditions, a multichannel distributed DAQ has been design to read out the signals from the 704 channels. With over 25 Ms/s sampling rate and 12 bit resolution for each channel, it can record the time and amplitude information as well as traditional DAQs in the TPC application domain. The main design objective of this distributed DAQ, however, is more flexible parameter modulation and operation. It can support the n-TPC without the limitation of the chassis and categorize signals arriving from the 704 channels at the same time by different events without event triggers.