High Energy Neutrino Generator for Neutrino Telescopes

We present the high energy neutrino Monte Carlo event generator ANIS (All Neutrino Interaction Simulation). The aim of the program is to provide a detailed and flexible neutrino event simulation for high energy neutrino detectors, such as AMANDA and ICECUBE. It generates neutrinos of any flavor according to a specific flux, propagates them through the Earth and in a final step simulates neutrino interactions within a specified volume. All relevant standard model processes are implemented. We discuss strength and limitations of the program, and provide as an example event rates for atmospheric and E^-2 neutrino spectra.Comment: 4 pages, 4 figures, ICRC2003 proceedings contributio

ANIS: High Energy Neutrino Generator for Neutrino Telescopes

We present the high-energy neutrino Monte Carlo event generator ANIS (All Neutrino Interaction Simulation). The program provides a detailed and flexible neutrino event simulation for high-energy neutrino detectors, such as AMANDA, ANTARES or ICECUBE. It generates neutrinos of any flavor according to a specified flux and propagates them through the Earth. In a final step neutrino interactions are simulated within a specified volume. All relevant standard model processes are implemented. We discuss strengths and limitations of the program.Comment: 15 pages, 4 figure

A dip in the UHECR spectrum and the transition from galactic to extragalactic cosmic rays

The dip is a feature in the diffuse spectrum of ultra-high energy (UHE) protons caused by electron-positron pair production on the cosmic microwave background (CMB) radiation. For a power-law generation spectrum $E^{-2.7}$, the calculated position and shape of the dip is confirmed with high accuracy by the spectra observed by the Akeno-AGASA, HiRes, Yakutsk and Fly's Eye detectors. When the particle energies, measured in these detectors, are calibrated by the dip, their fluxes agree with a remarkable accuracy. The predicted shape of the dip is quite robust. The dip is only modified strongly when the fraction of nuclei heavier than protons is high at injection, which imposes some restrictions on the mechanisms of acceleration operating in UHECR sources. The existence of the dip, confirmed by observations, implies that the transition from galactic to extragalactic cosmic rays occurs at E \lsim 1\times 10^{18} eV. We show that at energies lower than a characteristic value $E_{\rm cr}\approx 1\times 10^{18}$ eV, the spectrum of extragalactic cosmic rays flattens in all cases of interest, and it provides a natural transition to a steeper galactic cosmic ray spectrum. This transition occurs at some energy below $E_{\rm cr}$, corresponding to the position of the so-called second knee. We discuss extensively the constraints on this model imposed by current knowledge of acceleration processes and sources of UHECR and compare it with the traditional model of transition at the ankle.Comment: Version Accepted for Publication in Astroparticle Physics (minor changes

Effect of pre-straining on the aging behavior and mechanical properties of an Al-Cu-Mg-Ag alloy

The effects of cold deformation prior to aging on the precipitation behavior, microstructure and mechanical properties of an Al-5.6Cu-0.72 Mg-0.5Ag-0.32Mn-0.17Sc-0.12Zr (in wt%) alloy were investigated. Pre-straining disrupts the formation of Mg–Ag co-clusters, modifying the normal precipitation sequenc