Readout Electronics for CEPC Semi-Digital Hadron Calorimeter Pre-prototype

TL;DR

This paper presents a feasible readout electronics system for a GEM-based semi-digital hadron calorimeter prototype, demonstrating low noise, high efficiency, and stable performance suitable for use in the CEPC experiment.

Contribution

It introduces a novel readout electronics design for GEM detectors in semi-digital calorimeters, with successful testing on a prototype showing promising performance metrics.

Findings

Equivalent RMS noise below 0.35fC

Detection efficiency over 95% for MIP

Stable operation with gain variation less than 1%

Abstract

CEPC (Circular Electron and Positron Collider) is a large experiment facility proposed by Chinese particle physics community. One of its running option is being the Higgs factory. Calorimeter is the main part of this experiment to measure the jet energy. Semi-digital hadron calorimeter (SDHCAL) is one of the options for the hadron measurement. GEM detector with its high position resolution and flexible configuration is one of the candidates for the active layer of the SDHCAL. The main purpose of this paper is to provide a feasible readout method for the GEM-based semi-digital hadron calorimeter. A small-scale prototype is designed and implemented, including front-end board (FEB) and data interface board (DIF). The prototype electronics has been tested. The equivalent RMS noise of all channels is below 0.35fC. The dynamic range is up to 500fC and the gain variation is less than 1%. The readout electronics is applied on a double-layer GEM detector with 1cm*1cm readout pad. Result indicates that the electronics works well with the detector. The detection efficiency of MIP is over 95% with 5fC threshold.