Seminar in Hadronic Physics

Coherent parton energy loss: from colliders to cosmic rays

Greg Jackson

Institute for Nuclear Physics
University of Washington

Gluon radiation, when induced by an incoming energetic parton that crosses a ‘cold’ nuclear medium, is shown to significantly impact hadron spectra in proton-nucleus collisions. The corresponding energy loss stems from the interference between initial and final state colour configurations for the underlying partonic subprocess. Quenching of heavy and light mesons due solely to this mechanism is important at LHC energies and quantitatively (at least) on par with expected suppression from nuclear modifications to parton distribution functions. As a further application, we study collisions of cosmic rays with light nuclei in the Earth's atmosphere and find a sizeable reduction in the corresponding neutrino flux induced by semileptonic decays.