185 research outputs found
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
Non-extensivity Parameter of Thermodynamical Model of Hadronic Interactions at LHC energies
The LHC measurements above SPS and Tevatron energies give the opportunity to
test predictions of non-extensive thermodynamical picture of hadronic
interaction to examine measured transverse momenta distributions for new
interaction energy range. We determined Tsallis model non-extensivity parameter
for the hadronization process before short-lived particles decayed and distort
the initial p_t distribution. We have shown that it follows exactly smooth rise
determined at lower energies below present LHC record. The shape of the q
parameter energy dependence is consistent with expectations and the evidence of
the asymptotic limit may be seen.Comment: 2 pages, 2 figure
Depth of maximum of extensive air showers and cosmic ray composition above 10**17 eV in the geometrical multichain model of nuclei interactions
The depth of maximum for extensive air showers measured by Fly's Eye and
Yakutsk experiments is analysed. The analysis depends on the hadronic
interaction model that determine cascade development. The novel feature found
in the cascading process for nucleus-nucleus collisions at high energies leads
to a fast increase of the inelasticity in heavy nuclei interactions without
changing the hadron-hadron interaction properties. This effects the development
of the extensive air showers initiated by heavy primaries. The detailed
calculations were performed using the recently developed geometrical multichain
model and the CORSIKA simulation code. The agreement with data on average depth
of shower maxima, the falling slope of the maxima distribution, and these
distribution widths are found for the very heavy cosmic ray mass spectrum
(slightly heavier than expected in the diffusion model at about 3*10**17 eV and
similar to the Fly's Eye composition at this energy).Comment: 11pp (9 eps figures
Bose-Einstein source of intermittency in hadronic interactions
The multi-particle Bose-Einstein correlations are the source of
''intermittency'' in high energy hadronic collisions. The power-law like
increase of factorial moments with decreasing bin size was obtained by complete
event weighing technique with gaussian approximation of space-time particle
emitting source shape. The value of source size parameter was found to be
higher than the common one fitted with the help of the standard Handbury
Brown-Twiss procedure.Comment: 12
Educational studies of cosmic rays with telescope of Geiger-Muller counters
A group of high school students (XII Liceum) in the framework of the Roland
Maze Project has built a compact telescope of three Geiger-Muller counters. The
connection between the telescope and PC computer was also created and programed
by students involved in the Project. This has allowed students to use their
equipment to perform serious scientific measurements concerning the single
cosmic ray muon flux at ground level and below. These measurements were then
analyzed with the programs based on the 'nowadays' knowledge on statistics. An
overview of the apparatus, methods and results were presented at several
students conferences and recently won the first prize in a national competition
of high school students scientific work. The telescope itself, in spite of its
'scientific' purposes, is built in such a way that it is hung on a wall in a
school physics lab and counts muons continuously. This can help to raise the
interest for studying physics among others. At present a few (3) groups of
young participants of the Roland Maze Project have already built their own
telescopes for their schools and some others are working on it. This work is a
perfect example of what can be done by young people when respective
opportunities are created by more experienced researchers and a little help and
advice is given.Comment: 5 figures, 10 page
EAS experiment on board of the Airbus A380
We consider taking the opportunity of about 10.000 hours of test of the Airbus A380, and to install at passenger space detectors for high energy cosmic ray events. The altitude of 10 km (250 g/cm 2 ) would give opportunity to measure EAS originating from heavy primaries to energies exceeding 10 7 GeV, and also coming without interaction proton component beyond the energy of the knee. At the altitude the iron originated EAS are well developed and registering their lateral distribution in 70 meters long cabin it is possible to distinguish them from proton originated EAS. Hadron component of EAS (registered as number of secondary hadrons produced in the detector) would help in discrimination and energy estimation. On another hand, registrations of high energy protons (without EAS) would enable to measure high energy proton spectrum. The energy of the proton would be estimated via hadron multiplicity in single interaction inside the detector. We propose to use about 60 modules of 0.5 m 2 of active detectors with scintillators to detect E-M component and carbon target with lead layer to detect the hadronic component via neutron registrations
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