Development of a Modular Current-Mode NaI(Tl) Detector Array for Parity Odd (n,{\gamma}) Cross Section Measurements

TL;DR

This paper presents a modular NaI(Tl) detector array designed for precise measurements of parity-odd effects in neutron-nucleus interactions, demonstrating successful detection of known parity violation in 139La.

Contribution

The paper introduces a novel modular detector array with custom electronics capable of pulse and current mode operation for parity violation experiments.

Findings

Successfully detected the 0.7 eV parity-violating resonance in 139La

Demonstrated the array's ability to measure parity-odd asymmetries

Validated the detector design through characterization and testing

Abstract

The Neutron Optics Parity and Time-Reversal Violation Experiment (NOPTREX) Collaboration has developed a modular array of 24 NaI(Tl) detectors to measure parity and time-reversal symmetry violation in neutron-nucleus interactions. These detectors feature custom electronics that allow for operation in pulse or current mode. This paper describes the design, construction, characterization, and testing of the detectors in this array. We demonstrate the ability of the array to detect parity-odd asymmetries in neutron resonances by observing the known 0.7 eV parity-violating resonance in 139La in measurements at LANSCE.