# A compact and modular X and gamma-ray detector with a CsI scintillator and double-readout Silicon Drift Detectors

## TL;DR

This paper presents a novel compact X and gamma-ray detector using CsI scintillators and double-readout Silicon Drift Detectors, with digital discrimination algorithms for different energy ranges, suitable for astrophysical applications.

## Contribution

The paper introduces a modular, compact detector design with integrated digital algorithms for event discrimination, advancing future astrophysical gamma-ray instrumentation.

## Key findings

- Prototype characterization demonstrates effective event discrimination.
- Modular design supports future astrophysical missions like THESEUS.
- Digital algorithms improve energy range detection accuracy.

## Abstract

A future compact and modular X and gamma-ray spectrometer (XGS) has been designed and a series of prototypes have been developed and tested. The experiment envisages the use of CsI scintillator bars read out at both ends by single-cell 25 mm2 Silicon Drift Detectors. Digital algorithms are used to discriminate between events absorbed in the Silicon layer (lower energy X rays) and events absorbed in the scintillator crystal (higher energy X rays and gamma-rays). The prototype characterization is shown and the modular design for future experiments with possible astrophysical applications (e.g. for the THESEUS mission proposed for the ESA M5 call) are discussed.