A UV Sensitive Integrated Micromegas with Timepix Readout

TL;DR

This paper introduces an integrated UV-sensitive detector combining a CMOS array, Micromegas, and CsI photocathode, achieving high gain and resolution for single UV-photon detection.

Contribution

It demonstrates a monolithically integrated detector system with reliable operation and high-resolution imaging capabilities for UV-photon detection.

Findings

Achieved charge gains up to 6 x 10^4 for single photons.

Operated reliably in He/isobutane gas mixtures.

High-resolution imaging with an MTF50 of 0.4 lp/pixel.

Abstract

This article presents a detector system consisting of three components, a CMOS imaging array, a gaseous-detector structure with a Micromegas layout and a UV-photon sensitive CsI reflective photocathode. All three elements have been monolithically integrated using simple post-processing steps. The Micromegas structure and the CMOS imaging chip are not impacted by the CsI deposition. The detector operated reliably in He/isobutane mixtures and attained charge gains with single photons up to a level of 6 \cdot 10^4. The Timepix CMOS array permitted high resolution imaging of single UV-photons. The system has an MTF50 of 0.4 lp/pixel which corresponds to app. 7 lp/mm.