Drell-Yan studies in ppbar reactions at FAIR

Abstract

The nucleonic structure is far to be completely understood. A transverse momentum dependent description of the nucleon structure is a crucial milestone for several forthcoming studies in a wide range of experimental scenarios. By mean of antiproton beams, eventually polarized, that will be available at the future FAIR facility with a beam momentum up to 15 GeV/c, the non-perturbative region of the QCD could be accessed. One of the main goal of the forthcoming experiments at FAIR is the investigation of those Drell-Yan lepton pairs produced in proton-antiproton annihilations, taking advantage of the high expected luminosities. Drell-Yan studies are a unique tool to access the spin depending properties of the nucleon, and namely its transverse degrees of freedom. Transverse Momentum Dependent (TMD) Parton Distribution Functions (PDFs), in particular the Boer-Mulders, the Sivers and the Transversity distribution functions, could be widely investigated by mean of the corresponding experimental azimuthal asymmetries. In later stages of FAIR, single- and double-spin asymmetries could be investigated as well. The Drell-Yan physics program which could be accessed at FAIR will be discussed in details, with a particular focus on the PANDA experimental scenario.