Perspectives of a single-anode cylindrical chamber operating in ionization mode and high gas pressure

TL;DR

This study investigates a single-anode cylindrical gas detector operating at high pressure for rare event detection, demonstrating high energy resolution and stable performance across different gases and pressures.

Contribution

It presents experimental results on the performance of a high-pressure cylindrical gas detector using argon and xenon, highlighting its potential for rare decay searches.

Findings

Achieved energy resolution better than 1.5% FWHM at high pressure

Detected stable performance across argon and xenon gases

No significant energy degradation with increasing pressure

Abstract

As part of the R2D2 (Rare Decays with Radial Detector) R&D, the use of a gas detector with a spherical or cylindrical cathode, equipped with a single anode and operating at high pressure, was studied for the search of rare phenomena such as neutrinoless double-beta decay. The presented measurements were obtained with a cylindrical detector, covering gas pressures ranging from 1 to 10 bar in argon and 1 to 6 bar in xenon, using both a point-like source of $^{210}$Po (5.3 MeV $\alpha$ ) and a diffuse source of $^{222}$Rn (5.5 MeV $\alpha$). Analysis and interpretation of the data were developed using the anodic current waveform. Similar detection performances were achieved with both gases, and comparable energy resolutions were measured with both sources. As long as the purity of the gas was sufficient, no significant degradation of the measured energy was observed by increasing the pressure. At the highest operating pressure, an energy resolution better than 1.5% full-width at half-maximum (FWHM) was obtained for both gaseous media, although optimal noise conditions were not reached.