Atmospheric lepton fluxes at very high energy

Understand

The observation of astrophysical neutrinos requires a detailed understanding of the atmospheric neutrino background.

• Since neutrinos are produced in meson decays together with a charged lepton, important constraints on this background can be obtained from the measurement of the atmospheric muon flux.
• Muons, however, can also be produced as mu+ mu- pairs by purely electromagnetic processes.
• We use the Z-moment method to study and compare the contributions to the atmospheric muon and neutrino fluxes from different sources (pi/K decay, charmed and unflavored hadron decay, and photon conversion into a muon pair).