400 research outputs found
Scaling Violation and Inelasticity of Very High Energy Proton-Proton Interactions
The pseudorapidity measurements at LHC, although in the central region only,
allows to perform preliminary tests of the multiparticle production
extrapolation formula inspired by the recent cosmic ray data analysis. Feynman
scaling violation in the form proposed originally by Wdowczyk and Wolfendale in
70s has been applied to the Pierre Auger Observatory and the Hi-Res group
measurements. The consistency of the Extensive Air Shower development and
anisotropy data was found for smoothly rise of the scaling violation parameter.
We have shown that the longitudinal momenta of produced particles determined
inclusively as rapidity (pseudorapidity) distributions measured by LHC
experiments follow the some universal high energy distribution scaled
respectively. The high degree of Feynman scaling violation is confirmed. The
decrease of the very high energy interaction inelasticity suggested by cosmic
ray data analysis is found to be consistent with LHC measurements up to 7 TeV
Propagation and nucleosynthesis of ultraheavy cosmic rays
The observed fluxes of cosmic ray (C.R.) ultraheavy elements depend on their charge and mass spectrum at the sources and on the propagation effects, on the distribution of path lengths traversed by the particles on their way from the sources to the observation point. The effect of different path length distributions (p.l.d.) on the infered source abunances is analyzed. It seems that it is rather difficult to fit a reasonable p.l.d. so that the obtained source spectrum coincides with the Solar System (SS) abundances in more detail. It suggests that the nucleosynthesis conditions for c.r. nuclei may differ from that for SS matter. The nucleosynthesis of ultraheavy elements fitting its parameters to get the c.r. source abundances is calculated. It is shown that it is possible to get a very good agreement between the predicted and the observed source abundance
The knee in the cosmic ray energy spectrum: a pulsar/supernova origin?
The origin of the prominent 'knee' in the cosmic ray energy spectrum at an
energy of several PeV is still uncertain. A recent mechanism has shown promise,
however; this involves particles from a very young pulsar interacting with the
radiation field from a very young supernova remnant. The ensuing nuclear
reaction of the particles with the photons by way of e+e- production then
causes the characteristic knee. In an earlier paper we argued that the
mechanism would imply only one source of a very rare type - if it were to
explain the spectral shape. Here we examine the mechanism in more detail and
conclude that for even a single source to work its characteristics would need
to be so unusual that the mechanism would not be possible for any known type of
pulsar-supernova combination
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