Predicting prompt atmospheric neutrino fluxes @ IceCube

I will present an updated prediction of the flux of neutrinos arising from the prompt decay of charmed hadrons formed in collisions of cosmic rays in the upper atmosphere. This flux of “prompt” atmospheric neutrinos is an important background in searches for high energy astrophysical neutrinos by neutrino telescopes such as IceCube. Our calculation is semi-analytic, employs NLO pQCD Monte-Carlo event generation and up-to-date parton distribution functions, and has been validated in detail with the recent LHCb charm production data, which cover a similar kinematical region. The calculation of the lepton fluxes is performed in the well-established framework of “cascade” equations, which trace the (re)generation and evolution of nucleons, mesons, and leptons in the Earth’s atmosphere. Our results, while apparently consistent with previous studies, will provide a more robust uncertainty evaluation and possibly alleviate tensions with current IceCube analyses.