Timing characterization of MALTA and MALTA2 pixel detectors using Micro X-ray source

TL;DR

This paper presents timing characterization of MALTA and MALTA2 pixel detectors using X-ray sources, overcoming challenges posed by metallic layers that hinder laser-based timing measurements, and reports a response time of approximately 2.6 ns for MALTA2.

Contribution

It introduces an X-ray based timing measurement method for monolithic pixel detectors with metallic layers, providing a new approach for their characterization.

Findings

MALTA2 pixel detectors have a response time of about 2.6 ns.

X-ray techniques are effective for timing studies of detectors with metallic layers.

The timing setup was validated using LGAD detectors.

Abstract

The MALTA monolithic active pixel detector is developed to address some of the challenges anticipated in future high-energy physics detectors. As part of its characterization, we conducted timing studies necessary to provide a figure of merit for this family of monolithic pixel detectors. MALTA has a metal layer in front-end electronics, and the conventional laser technique is not suitable for timing studies due to the reflection of the laser from the metallic surface. X-rays have been employed as a more effective alternative for penetration through these layers. The triggered X-ray set-up is designed to study timing measurements of monolithic detectors. The timing response of the X-ray set-up is characterized using an LGAD. The timing response of the MALTA and MALTA2 pixel detectors is studied, and the best response time of MALTA2 pixel detectors is measured at about 2.6 ns.