Studying the GRAiNITA concept: first test beam results

TL;DR

This study presents initial test beam results of the GRAiNITA detector prototype, demonstrating promising energy resolution performance and low non-uniformity, supporting its potential for future calorimetric applications.

Contribution

First experimental characterization of GRAiNITA prototype performance using test beam data at CERN SPS.

Findings

Non-uniformity-related constant term below 1%.

Photo-electron statistics contribute about 1%/sqrt(E) to energy resolution.

Results support the expected calorimetric performance of GRAiNITA.

Abstract

Data collected over a two-day period in June 2024 at the CERN SPS H9 test beam using a small-scale GRAiNITA prototype have been analyzed to characterize the detector's energy resolution performance. The measurements allow for a first estimate of the constant term associated with detector non-uniformity. Although the evaluation is limited by the small prototype size and the use of pion beams, the results indicate that the non-uniformity-related constant term is significantly below 1%. Furthermore, the test-beam data confirm that the contribution to the energy resolution arising from photo-electron statistics is approximately 1%/sqrt(E). These findings validate the expected calorimetric performance of the GRAiNITA concept and provide important input for the design and optimization of future full-scale detectors.