Tests of a Digital Hadron Calorimeter

TL;DR

This paper reports on extensive testing of a small-scale digital hadron calorimeter prototype with high granularity, evaluating its response to various particles and conditions for future collider applications.

Contribution

It presents the first detailed performance evaluation of a high-granularity RPC-based digital hadron calorimeter prototype for particle flow algorithms.

Findings

Calorimeter response to muons, pions, and positrons was characterized in the 1-16 GeV range.

Efficiency measurements under different beam intensities were performed and analyzed.

Data compared favorably with GEANT4 simulations and analytical models.

Abstract

In the context of developing a hadron calorimeter with extremely fine granularity for the application of Particle Flow Algorithms to the measurement of jet energies at a future lepton collider, we report on extensive tests of a small scale prototype calorimeter. The calorimeter contained up to 10 layers of Resistive Plate Chambers (RPCs) with 2560 1 \times 1 cm2 readout pads, interleaved with steel absorber plates. The tests included both long-term Cosmic Ray data taking and measurements in particle beams, where the response to broadband muons and to pions and positrons with energies in the range of 1 - 16 GeV was established. Detailed measurements of the chambers efficiency as function of beam intensity have also been performed using 120 GeV protons at varying intensity. The data are compared to simulations based on GEANT4 and to analytical calculations of the rate limitations.