Speaker
Description
At the highest energies, the prompt atmospheric neutrino flux from charmed-hadron decays contributes to the background in astrophysical neutrino source searches, but remains uncertain due to sparse constraints on forward heavy-flavor production and differences among hadronic interaction models. Atmospheric muons probe related air-shower physics and complement neutrino measurements: prompt neutrinos are dominated by charm decays, whereas prompt muons receive contributions from both charm and short-lived unflavoured mesons. Conventional muons from pion and kaon decays constrain light-meson production in air showers, which also governs the conventional atmospheric neutrino flux. We unfold the atmospheric muon flux in IceCube from sub-TeV to PeV energies using stopping and through-going muon samples. Improved machine-learning reconstructions and event selections enable a robust unfolding accounting for detector and ice systematic effects. We present the unfolded spectra, derive constraints on the prompt fraction in the atmospheric muon flux, and relate these results to prompt atmospheric neutrino expectations.
