Ionization signals from electrons and alpha-particles in mixtures of liquid Argon and Nitrogen - perspectives on protons for Gamma Resonant Nuclear Absorption applications

TL;DR

This study investigates ionization signals in liquid Argon-Nitrogen mixtures within a TPC, aiming to enhance gamma-ray detection for security and medical uses, and predicts proton signals through interpolation.

Contribution

It provides detailed measurements of ionization signals in Ar-N2 mixtures and offers a prediction method for proton signals relevant to gamma-ray detection applications.

Findings

Ionization signals depend on Nitrogen concentration and electric field.

Proton signals are predicted via interpolation based on electron and alpha data.

Liquid Ar-N2 TPCs show promise for gamma-ray detection in security and medical fields.

Abstract

In this paper we report on a detailed study of ionization signals produced by Compton electrons and alpha-particles in a Time Projection Chamber (TPC) flled with different mixtures of liquid Argon and Nitrogen. The measurements were carried out with Nitrogen concentrations up to 15% and a drift electric feld in the range 0-50 kV/cm. A prediction for proton ionization signals is made by means of interpolation. This study has been conducted in view of the possible use of liquid Ar-N2 TPCs for the detection of gamma-rays in the resonant band of the Nitrogen absorption spectrum, a promising technology for security and medical applications.