Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams

TL;DR

A novel time projection chamber was developed at J-PARC for precise neutron lifetime measurement using pulsed cold neutron beams, featuring innovative background suppression techniques.

Contribution

The paper introduces a new TPC design with advanced materials and configurations to improve neutron lifetime measurement accuracy.

Findings

Successful design and performance validation of the new TPC

Effective background suppression using $^6$Li-enriched tiles

Enhanced neutron detection capabilities

Abstract

A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.