In-flight performance of the DAMPE silicon tracker

TL;DR

This paper evaluates the in-flight performance of DAMPE's silicon tracker over two years, focusing on noise, signal response, stability, and resolution to ensure its effectiveness in cosmic ray and gamma-ray detection.

Contribution

It provides the first comprehensive analysis of DAMPE's silicon tracker performance during space operation, highlighting its stability and measurement capabilities.

Findings

Stable noise behavior observed over two years

Effective signal response and spatial resolution

Maintained thermal and mechanical stability

Abstract

DAMPE (DArk Matter Particle Explorer) is a spaceborne high-energy cosmic ray and gamma-ray detector, successfully launched in December 2015. It is designed to probe astroparticle physics in the broad energy range from few GeV to 100 TeV. The scientific goals of DAMPE include the identification of possible signatures of Dark Matter annihilation or decay, the study of the origin and propagation mechanisms of cosmic-ray particles, and gamma-ray astronomy. DAMPE consists of four sub-detectors: a plastic scintillator strip detector, a Silicon-Tungsten tracKer-converter (STK), a BGO calorimeter and a neutron detector. The STK is composed of six double layers of single-sided silicon micro-strip detectors interleaved with three layers of tungsten for photon conversions into electron-positron pairs. The STK is a crucial component of DAMPE, allowing to determine the direction of incoming photons, to reconstruct tracks of cosmic rays and to estimate their absolute charge (Z). We present the in-flight performance of the STK based on two years of in-flight DAMPE data, which includes the noise behavior, signal response, thermal and mechanical stability, alignment and position resolution.