Speaker
Description
Low-energy cosmic anti-deuterons are unique probe for search of exotic processes in the Universe such as Dark Matter annihilation, since the production rate of these ions through secondary processes in interstellar medium is very low. However, the lack of experimental data at low energies hampers precise predictions of the expected anti-deuteron fluxes near Earth, with both anti-deuteron nuclear inelastic cross-section with matter and anti-deuteron production cross-section being known very poorly by today.
In ultra-relativistic collisions of protons and lead ions at the CERN's Large Hadron Collider matter and anti-matter is produced in almost equal abundances. This allows us not only to study the production cross-sections of (anti-)deuterons with high precision, but also to quantify the absorption of produced (anti-)deuterons in the detector material. The latter can be investigated via comparison of raw reconstructed yields of particles and anti-particles in experimental data and in Monte Carlo simulations.
In this talk we present the first results on the anti-deuteron absorption cross-section in the ALICE detector material using p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV. The reconstructed anti-deuteron to deuteron ratio is compared to the results from detailed simulations of the ALICE detector based on different versions of the GEANT toolkit for particle propagation and interaction with matter. First experimental constraints on the anti-deuteron nuclear inelastic cross-section are extracted in the momentum range between 0.3 and 4.0 GeV/$c$. Finally, we discuss the perspectives for future measurements using high-statistics data from proton-proton collisions at $\sqrt{s}$ = 13 TeV.
