Performance of the DAMPE BGO calorimeter on the ion beam test

Abstract The DArk Matter Particle Explorer (DAMPE), which is a Chinese space telescope for the precise measurement of high-energy electrons, gamma rays, and nuclei from deep space, was successfully launched on December 17, 2015. The DAMPE electromagnetic calorimeter made of bismuth germanium oxide (BGO) crystals can measure incident hadron energies from 50 GeV to 100 TeV. The calorimeter was tested with ion beams at CERN in 2015. The energy responses to ions from helium to argon are investigated. The result is reproduced by a Monte Carlo simulation based on Geant4 with two physics process models. It shows that the simulation results of a beam test are independent of the physics models adopted. Additionally, quenching effects of the BGO crystal on the ions are observed with this beam test. The quenching attenuations increase with the atomic number and were approximately 7% for boron and 40% for argon.