Correction Method for the Readout Saturation of the DAMPE Calorimeter

TL;DR

This paper presents a correction method for readout saturation in the DAMPE BGO calorimeter, improving energy measurement accuracy for ultra-high-energy cosmic-ray events.

Contribution

It introduces a novel correction technique based on shower topologies and neighboring crystal measurements to address saturation issues.

Findings

The method accurately reconstructs energy deposits in saturated crystals.

Validation with simulated and real data confirms the correction effectiveness.

Improves the energy measurement precision for high-energy cosmic-ray events.

Abstract

The DArk Matter Particle Explorer (DAMPE) is a space-borne high energy cosmic-ray and $\gamma$-ray detector which operates smoothly since the launch on December 17, 2015. The bismuth germanium oxide (BGO) calorimeter is one of the key sub-detectors of DAMPE used for energy measurement and electron proton identification. For events with total energy deposit higher than decades of TeV, the readouts of PMTs coupled on the BGO crystals would become saturated, which results in an underestimation of the energy measurement. Based on detailed simulations, we develop a correction method for the saturation effect according to the shower development topologies and energies measured by neighbouring BGO crystals. The verification with simulated and on-orbit events shows that this method can well reconstruct the energy deposit in the saturated BGO crystal.