Results overview from the DAMPE space mission in orbit

Abstract

The Dark Matter Particle Explorer (DAMPE), is a space–borne detector designed for precise galactic Cosmic Ray (CR) studies in a wide energy range (up to 100 TeV), along with detailed measurements of high–energy gamma–rays and indirect searches of Dark Matter (DM) annihilation/decay to detectable particles. The satellite was launched into a sun–synchronous orbit at 500 km, on December 17th 2015 and has been successfully acquiring data ever since. The instrument consists of four sub-detectors, namely: a Plastic Scintillator Detector (PSD), a Silicon TracKerconverter (STK), a deep Bismuth Germanate (BGO) calorimeter 32 X0, 1.6 λI ) and a NeUtron Detector (NUD). DAMPE provided valuable insight on the cosmic-ray electron+positron (CRE) spectrum, unveiling a clear spectral break at 0.9 TeV with unprecedented energy resolution. Moreover, recent results regarding CR protons reveal a spectral hardening (at few hundred GeV) followed by a softening feature at 10 TeV. These features are well described by a smoothly-broken power law (SBPL), which differs from the paradigm of a unique power law (PL) spectrum extending up to PeV energies, hence necessitating a careful reconsideration of prevailing CR models. Additional insights concerning spectral measurements of helium, medium (i.e, boron, carbon, nitrogen, oxygen) and heavier mass nuclei (iron), will be presented in this work. Preliminary results on secondary-over-primary ratios (i.e., B/C and B/O) crucial in deciphering the nature of CR propagation in the Galaxy, will also be discussed, including a general synopsis of the mission status.