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1.
Cosmic rays of the highest energy, above the Greisen-Zatsepin-Kuzmin (GZK) cutoff of the spectrum, may originate in decays
of superheavy long-lived particles. We conjecture that these particles may be produced naturally in the early Universe from
vacuum fluctuations during inflation and may constitute a considerable fraction of cold dark matter. We predict a new cutoff
in the ultrahigh-energy cosmic ray spectrum E
cutoff<m
inflaton≈1013 GeV, the exact position of the cutoff and the shape of the cosmic ray spectrum beyond the GZK cutoff being determined by
the QCD quark/gluon fragmentation. The Pierre Auger Project installation may in principle observe this phenomenon.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 4, 255–259 (25 August 1998) 相似文献
2.
The differential energy spectrum of cosmic rays that is obtained on the basis of the measurements of Cherenkov radiation from
extensive air showers in an energy range of 1015–1020 eV is compared with the model of the propagation of primary particles in the interstellar medium with fractal properties.
It is found that the shape of the experimental spectrum is in good agreement with the shape of the calculated spectrum of
“all particles” at 1015–1018 eV. The average mass composition of cosmic rays that is calculated on the basis of five components does not contradict the
average mass composition obtained from the experimental data for several parameters in this energy range.
Original Russian Text ? S.P. Knurenko, A.A. Ivanov, A.V. Saburov, 2007, published in Pis’ma v Zhurnal éksperimental’noĭ i
Teoreticheskoĭ Fiziki, 2007, Vol. 86, No. 10, pp. 709–712. 相似文献
3.
V. I. Ermakov V. P. Okhlopkov Yu. I. Stozhkov 《Moscow University Physics Bulletin》2009,64(2):214-217
Flows of material particles, viz., cosmic rays and cosmic dust, are perpetually coming from space into the Earth’s atmosphere;
these are particles sized from 0.001 μm to dozens or hundreds of μm. The paper shows that cosmic rays influence the main parameters
of the atmosphere’s electricity, and cosmic dust influences global cloudiness, albedo and the Earth’s climate.
Original Russian Text ? V.I. Ermakov, V.P. Okhlopkov, Yu.I. Stozhkov, 2009, published in Vestnik Moskovskogo Universiteta.
Fizika, 2009, No. 2, pp. 104–106. 相似文献
4.
V. Ye. Sdobnov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(6):805-807
Based on the data from ground observations of cosmic rays (CRs) obtained by the spectrographic global survey method on the
worldwide network of stations, the variations in the rigidity spectrum and anisotropy of galactic cosmic rays were investigated,
along with changes in the geomagnetic cutoff rigidity in May 2005. A high degree of anisotropy (∼40–60% for the first spherical
harmonics and ∼5–6% for the second spherical harmonics) was observed for particles with a rigidity of 4 GV at the moments
of the maximum modulation of cosmic rays. 相似文献
5.
Chandran BD 《Physical review letters》2000,85(22):4656-4659
Scattering rates for a Goldreich-Sridhar (GS) spectrum of anisotropic, incompressible, magnetohydrodynamic turbulence are calculated in the quasilinear approximation. Because the small-scale fluctuations are constrained to have wave vectors nearly perpendicular to the background magnetic field, scattering is too weak to provide either the mean-free paths commonly used in Galactic cosmic-ray propagation models or the mean-free paths required for acceleration of cosmic rays at quasiparallel shocks. Where strong pitch-angle scattering occurs, it is due to fluctuations not described by the GS spectrum, such as fluctuations generated by streaming cosmic rays. 相似文献
6.
G. A. Bazilevskaya M. B. Krainev V. S. Makhmutov A. K. Svirzhevskaya N. S. Svirzhevsky Yu. L. Stozhkov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(6):782-785
The minimum between the 23rd and 24th cycles of solar activity was unusually deep and extended. The modulation of cosmic rays
was minimal for the more than 70-year-long period of direct measurements. The data from stratospheric measurements by the
Lebedev Physical Institute suggest that the flux of cosmic rays with more than 100 MeV/nucleon of energy exceeded the highest
ever observed level (May 1965) by almost 12%. However, the ground-based neutron monitors sensitive to relatively high energies
indicated that the flux of cosmic rays increased by less than 3%. This work compares the variations in the cosmic rays over
periods of five minima of solar activity (the 20th to the 24th cycle). It is shown that in late 2008, an extra flux of particles
with energies less than several GeV/nucleon was detected in the Earth’s orbit. A similar (though far smaller in scale) phenomenon
was also observed in 1987 at the same orientation of the Sun’s magnetic field A < 0, but was not observed in epochs where A > 0. 相似文献
7.
Two kinks are observed in the energy spectrum of galactic cosmic rays. It is shown that the entire spectrum can be described,
to a good approximation, by a single formula obtained on the basis of the hypothesis that the particles are produced and accelerated
in plasma pinches by an induction mechanism under the assumption that three hierarchical groups of currents are present—interstellar,
galactic, and metagalactic.
Pis’ma Zh. éksp. Teor. Fiz. 64, No. 4, 225–230 (25 August 1996) 相似文献
8.
New results of calculations of nucleon, π-and K-meson, and muon fluxes generated during high energy cosmic ray interactions
with the Earth’s atmosphere are presented. The calculations are based on the method of solving the nuclear cascade equations
with allowance for non-scaling behavior of inclusive hadron production cross sections, increase of cross sections of inelastic
hadron-nucleus collisions with energy, and non-power-law character of primary spectrum. The hadron and muon fluxes are calculated
at different atmospheric altitude levels for several spectral models and compositions of primary cosmic rays. Results of calculations
are compared with recent measurements using the L3+Cosmic and CosmoALEPH facilities.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 41–46, September, 2007. 相似文献
9.
S. V. Koldashov A. V. Sidorov N. D. Sharonova 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(6):773-775
The penetration of solar cosmic rays (SCRs) from interplanetary space into the Earth’s magneto-sphere is simulated numerically.
It is shown that the SCR energy spectrum observed in the magnetosphere changes when there is an anisotropic angular distribution
of SCRs in interplanetary space. 相似文献
10.
We show that “top-down” mechanisms of ultrahigh-energy cosmic rays which involve heavy relic particle-like objects predict
a Galactic anisotropy of the highest-energy cosmic rays at the level of minimum ∼ 20%. This anisotropy is large enough to
be either observed or ruled out in the next generation of experiments.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 2, 99–103 (25 July 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
11.
B. G. Sidharth 《Foundations of Physics》2008,38(1):89-95
Recent observations of ultra high energy cosmic rays and gamma rays suggest that there are small violations of Lorentz symmetry.
If there were no such violations, then the GZK cut off would hold and cosmic rays with energy ∼1020 eV or higher would not be reaching the earth. However some such events seem to have been observed. This has lead to phenomenological
models in which there is a small violation of the Lorentz symmetry or the velocity of light. However recent approaches which
no longer consider a differentiable spacetime manifold already predict such violations. Similarly there are other theoretical
reasons which also point to this. We briefly discuss some of these approaches and observe that Lorentz Symmetry violations
can be tested by data from NASA’s GLAST satellite due for launch.
Permanent address: International Institute for Applicable Mathematics & Information Sciences, Hyderabad, India & Udine, Italy.
B.M. Birla Science Centre, Adarsh Nagar, Hyderabad 500 063, India. 相似文献
12.
This paper presents a brief historical overview of studies of cosmic rays in the Earth’s atmosphere, which were initiated
and led by S.N. Vernov for over 50 years. The main results of these studies that were obtained in recent decades are given.
They include the study of the processes of generation and propagation of solar cosmic rays, the modulation of galactic cosmic
rays in the heliomagnetosphere, and the role of cosmic rays in atmospheric processes. 相似文献
13.
G. K. Ustinova 《Doklady Physics》2011,56(4):219-223
The effects of the shock wave diffusive acceleration of particles are considered in the case of formation of isotopic relations
of the anomalous Xe-HL component of xenon in relic grains of nanodiamonds in chondrites. It is shown that this component could be formed and captured
simultaneously with the nanodiamond synthesis in the conditions of the explosive shock wave propagation from supernova outbursts.
The specificity of isotopic composition of Xe-HL is due to the high hardness of the spectrum of nuclear-active particles at the shock wave front and its enrichment with heavy
isotopes. The spallogenic nature of both the anomalous and normal components of xenon is ascertained, and the role of the
subsequent evolutionary processes in the change of their isotopic systems is shown. Experimental evidence of the formation
of the power law spectrum of particles with the spectral index γ ∼ 1 by the supersonic turbulence during the carbon-detonation
supernova SnIa explosion is obtained; this perhaps opens new perspectives in studying the problem of the origin of cosmic
rays. It is shown that at the stage of free expansion of the explosive shock wave, the degree of compression of the matter
at the wave front was σ = 31 (the corresponding Mach number M ∼ 97); this led to a 31-fold increase of the magnetic field as well as of the maximum energy of accelerated particles, so
that even the energy of protons reached ∼ 3 × 1015 eV, i.e., the “knee” region. 相似文献
14.
N. I. Kochelev 《JETP Letters》1999,70(8):491-494
It is shown that an instanton-induced interaction between quarks produces a very deeply bound H dibaryon with mass below 2M
N
, viz., M
H
=1718 MeV. Therefore the H dibaryon is predicted to be a stable particle. The reaction of photodisintegration of the H dibaryon to 2Λ in the course of its motion in the cosmic microwave background will result in a new possible cutoff in the
cosmic-ray spectrum. This provides an explanation for the ultrahigh-energy cosmic ray events observed above the GZK cutoff
as being the result of the strong interaction of high-energy H dibaryons from cosmic rays with nuclei in the Earth’s atmosphere.
Pis’ma Zh. éksp. Teor. Fiz. 70, No. 8, 483–486 (25 October 1999)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
15.
The experimental study of high-energy cosmic rays at SINP is based on the legacy left by S.N. Vernov. An abrupt change (cutoff)
of the cosmic-ray energy spectrum in the range of ultrahigh energies, ∼5 × 1019 eV, was predicted in the works of Greisen-Zatsepin-Kuzmin (GZK). In these and in recent works, it was hypothesized that the
shape of the spectrum beyond the GZK limit is related to the evolution of the Universe at the earliest stage of its development,
which arouses special interest in studying such extremely high energies. At the same time, experimental study of cosmic-ray
particles with such high energies encounters difficulties in connection with their extremely low intensity. To develop a method
of particle detection on a maximum area of the order of the Earth’s disk area, in recent years it has been suggested to move
from ground-based to space-based detectors. The program of space experiments to study extremely-high-energy cosmic-ray particles
is discussed. 相似文献
16.
Kh. Namsrai 《Foundations of Physics》1985,15(2):129-143
It is suggested that the physical mechanism responsible for the acceleration of cosmic rays is due to the stochastic (or fluctuational) structure of space-time at small distances. A method of introducing fluctuations in a conformally flat Riemannian space-time metric due to ultrahigh energy particles is presented, from which a nonlinear dynamics of particles and equations for the electromagnetic field are obtained. The former admits the acceleration mechanism for cosmic-ray particles and the extreme energy increases during the evolution of the Universe. In our model the energy of the cosmic-ray particle and its radius (the effective Schwarzschild), the age of the universe, and the value of the fundamental length are connected with one another and are determined by a unified formula, Einstein's relation for the relativistic particle energy. It allows one to define experimentally the value of the fundamental length, which is l=1.56×10
–33 cm for the maximum proton energy observed in cosmic rays. The problem of the energy spectrum of the cosmic rays and the ratio of intensities of the electron component to the proton component at the same energy level are also discussed.On leave of absence from the Academy of Sciences, Mongolian People's Republic, Ulan-Bator, Mongolia. 相似文献
17.
A. V. Uryson 《Journal of Experimental and Theoretical Physics》1998,86(1):6-10
The complicated shape of the cosmic ray spectrum recorded by giant arrays in the energy range 1017–1020 eV is analyzed. It is shown that in the energy region ∼1018–1019 eV the spectrum probably coincides with the injection spectrum whose exponent is equal approximately to 3.2–3.3. The flatter
component in the energy region (3.2–5.0)×1019 eV is due to braking of extragalactic protons on primordial photons (the cosmic background radiation). At energies exceeding
3.2×1019 eV the spectrum does not have a blackbody cutoff. The possibility of determining the distances at which cosmic rays originate
and investigating the evolution of their sources on the basis of ultrahigh-energy cosmic ray data is discussed.
Zh. éksp. Teor. Fiz. 113, 12–20 (January 1998) 相似文献
18.
N. N. Kalmykov A. A. Konstantinov R. A. Mukhamedshin D. M. Podorozhnyi L. G. Sveshnikova A. N. Turundaevskii L. G. Tkachev A. P. Chubenko 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(3):347-349
A mathematical model for experiments aimed at studying the primary cosmic rays on the Moon’s surface and in orbit around the
Moon is considered. The feasibility of simultaneously registering in three components (secondary neutrons, gamma rays, and
radio emission) particles of primary cosmic rays via reverse current in showers developing in the lunar regolith is demonstrated. 相似文献
19.
E. G. Berezhko L. T. Ksenofontov 《Journal of Experimental and Theoretical Physics》1999,89(3):391-403
The kinetic theory of regular acceleration of cosmic rays in supernova remnants is used to investigate the expected chemical
composition of the rays. It is shown that the shapes of the calculated profiles of the chemical elements making up the cosmic
rays are consistent with experiment wherever the results of measurements are available. The acceleration process is accompanied
by relative enrichment of the cosmic rays with heavy elements. If the analogous property of the mechanism underlying the injection
of superthermal particles into the acceleration regime is taken into account, such enrichment supports the formation of the
required composition of cosmic rays in the energy range up to 1014–1015 eV.
Zh. éksp. Teor. Fiz. 116, 737–759 (September 1999) 相似文献
20.
S. K. Srivastava 《International Journal of Theoretical Physics》2007,46(6):1702-1709
Here, an accelerated phantom model for the late universe is explored, which is free from future singularity. It is interesting
to see that this model exhibits strong curvature for all time in future, unlike models with ‘big-rip singularity’ showing
high curvature near singularity time only. So, quantum gravity effects grow dominant as time increases in late universe too.
More importantly, it is demonstrated that quantum corrections to FRW equations lead to non-violation of ‘cosmic energy conditions’
of general relativity, which are violated for accelerating universe without these corrections. 相似文献