Paolo Lipari

Atmospheric neutrino flux above 1 GeV.

In this paper we extend an earlier calculation of the flux of atmospheric neutrinos to higher energy. The earlier calculation of the neutrino flux below 3 GeV has been used for calculation of the rate of contained neutrino interactions in deep underground detectors. The fluxes are needed up to neutrino energies of 10 TeV to calculate the expected rate of neutrino-induced muons passing into and through large, deep detectors. We compare our results with several other calculations, and we evaluate the uncertainty in the rate of neutrino-induced muons due to uncertainties in the neutrino flux. {copyright} {ital 1996 The American Physical Society.}

Lepton spectra in the earth's atmosphere

Abstract In this work we present an analytic calculation of the μ± and neutrino fluxes in the earths atmosphere. We discuss in detail the ratios νμ/ \ gnμ, νe/ \ gne and μ+/μ− as a function of particle energy and zenith angle. Precise knowledge of the neutrino/antineutrino ratios is necessary for the correct interpretation of neutrino oscillation experiments that use atmospheric neutrinos because of the different oscillation properties of neutrinos and antineutrinos in matter due to the Mikheyev-Smirnov-Wolfenstein mechanism. We also discuss the relation between muon and neutrino fluxes and the possibility to determine experimentally the non-oscillation neutrino fluxes from precise measurements of the muon flux.

Cosmic ray interaction event generator SIBYLL 2.1

The cosmic ray interaction event generator Sibyll is widely used in extensive air shower simulations. We describe in detail the properties of Sibyll 2.1 and the differences with the original version 1.7. The major structural improvements are the possibility to have multiple soft interactions, introduction of new parton density functions, and an improved treatment of diffraction. Sibyll 2.1 gives better agreement with fixed target and collider data, especially for the inelastic cross sections and multiplicities of secondary particles. Shortcomings and suggestions for future improvements are also discussed.

Flavor Composition and Energy Spectrum of Astrophysical Neutrinos

The measurement of the flavor composition of the neutrino fluxes from astrophysical sources has been proposed as a method to study not only the nature of their emission mechanisms, but also the fundamental neutrino properties. It is however problematic to reconcile these two goals, since a sufficiently accurate understanding of the neutrino fluxes at the source is needed to extract information about the physics of neutrino propagation. In this work we discuss critically the expectations for the flavor composition and energy spectrum from different types of astrophysical sources, and comment on the theoretical uncertainties connected to our limited knowledge of their structure.

Cosmic ray event generator Sibyll 2.1

The cosmic ray interaction event generator Sibyll is widely used in extensive air shower simulations. We describe in detail the properties of Sibyll 2.1 and the differences with the original version 1.7. The major structural improvements are the possibility to have multiple soft interactions, introduction of new parton density functions, and an improved treatment of diffraction. Sibyll 2.1 gives better agreement with fixed target and collider data, especially for the inelastic cross sections and multiplicities of secondary particles. Shortcomings and suggestions for future improvements are also discussed.

Ratio of vevμ in atmospheric neutrinos

Abstract When the effect of muon polarization is included, the calculated ratio v e v μ for atmospheric neutrinos with energies above ∼200 MeV is increased by 10–20% compared to the result when polarization is neglected. We give an analytic derivation of this ratio for the artificial case of power law differential spectrum of parent pions propagating in an atmosphere in which all pions and muons decay. This is sufficient to estimate the effect on the calculated ratio of electron-like to muon-like events induced by neutrino interactions in large underground detectors.

Matter effects in long-baseline experiments, the flavor content of the heaviest (or lightest) neutrino, and the sign of Δ m 2

The neutrinos of long-baseline beams travel inside the Earths crust where the density is

Geomagnetic effects on atmospheric neutrinos

\ensuremath{\rho}\ensuremath{\simeq}2.8{\mathrm{g}\mathrm{}\mathrm{cm}}^{\ensuremath{-}3}.

Gamma-Light: High-Energy Astrophysics above 10 MeV

If electron neutrinos participate in the oscillations, matter effects will modify the oscillation probabilities with respect to the vacuum case. Depending on the sign of

Proton-proton cross section at s ∼ 30 TeV

\ensuremath{\Delta}{m}^{2},