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Related papers: Do we observe L\'evy flights in cosmic rays?

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Cosmic rays with energies above $10^{18}$ eV are currently of considerable interest in astrophysics and are to be further studied in a number of projects which are either currently under construction or the subject of well-developed…

Astrophysics · Physics 2009-11-10 R. J. Protheroe , R. W. Clay

We investigate front propagation in a reacting particle system in which particles perform scale-free random walks known as Levy flights. The system is described by a fractional generalization of a reaction-diffusion equation. We focus on…

Statistical Mechanics · Physics 2007-05-23 D. Brockmann , L. Hufnagel

Probing the anomalous nanoscale intermixing using molecular dynamics (MD) simulations in Pt/Ti bilayer we reveal the superdiffusive nature of interfacial atomic transport. It is shown that the Pt atoms undergo anomalous atomic transport…

Materials Science · Physics 2008-02-18 P. Süle , M. Menyhárd

Large-deviations theory deals with tails of probability distributions and the rare events of random processes, for example spreading packets of particles. Mathematically, it concerns the exponential fall-of of the density of thin-tailed…

Statistical Mechanics · Physics 2017-07-04 Erez Aghion , David A. Kessler , Eli Barkai

After a short excursion from discovery of Brownian motion to the Richardson "law of four thirds" in turbulent diffusion, the article introduces the L\'{e}vy flight superdiffusion as a self-similar L\'{e}vy process. The condition of…

Statistical Mechanics · Physics 2015-05-13 A. A. Dubkov , B. Spagnolo , V. V. Uchaikin

Several independent pieces of information have recently hinted at a prominent role of cosmic rays in controlling their own transport, within and around the sources as well as throughout their propagation on Galactic scales and even possibly…

High Energy Astrophysical Phenomena · Physics 2019-05-28 Pasquale Blasi

The diffuse cosmic background radiation in the GALEX far ultraviolet (FUV, 1300 \AA\ - 1700 \AA) is deduced to originate only partially in the dust-scattered radiation of FUV-emitting stars: the source of a substantial fraction of the FUV…

Astrophysics of Galaxies · Physics 2015-06-19 Richard Conn Henry , Jayant Murthy , James Overduin , Joshua Tyler

We study the deflection of ultra high energy cosmic ray protons in different models of the regular galactic magnetic field. Such particles have gyroradii well in excess of 1 kpc and their propagation in the galaxy reflects only the large…

Astrophysics · Physics 2010-11-30 Todor Stanev

Our purpose is to evaluate the rate of the maximum energy and the acceleration rate that cosmic rays acquire in the non-relativistic diffusive shock acceleration as it could apply during their lifetime in various astrophysical sites, where…

Astrophysics · Physics 2009-11-11 A. Meli , P. L. Biermann

A numerical and analytical study of the role of exponentially truncated L\'evy flights in the superdiffusive propagation of fronts in reaction-diffusion systems is presented. The study is based on a variation of the Fisher-Kolmogorov…

Statistical Mechanics · Physics 2009-11-13 Diego del-Castillo-Negrete

The problem of the origin of cosmic rays in the shocks produced by supernova explosions at energies below the so called 'knee' (at ~3*10$^6$ GeV) in the energy spectrum is addressed, with special attention to the propagation of the…

Astrophysics · Physics 2008-11-26 A. D. Erlykin , A. A. Lagutin , A. W. Wolfendale

Concurrent observations of Lyman continuum (LyC) and Lyman-alpha (Lya) emission escaping from star-forming systems at low redshift are essential to understanding the physics of reionization at high redshift (z >~ 6). Some have suggested…

Astrophysics · Physics 2015-05-13 Stephan R. McCandliss

Truncated Levy flights are stochastic processes which display a crossover from a heavy-tailed Levy behavior to a faster decaying probability distribution function (pdf). Putting less weight on long flights overcomes the divergence of the…

Condensed Matter · Physics 2009-11-10 I. M. Sokolov , A. V. Chechkin , J. Klafter

Recent results by space borne experiments took cosmic ray data to a precision level. These new results are able to challenge the conventional scenario for cosmic ray acceleration and propagation in the Milky Way. In these contributions,…

High Energy Astrophysical Phenomena · Physics 2018-08-23 Manuela Vecchi

A substantial increase of the mean logarithmic mass $<\ln A>$ of galactic cosmic rays {\em vs} energy has been observed . We study three effects that could explain this trend i) different source spectra for protons and heavy nuclei ii) a…

Astrophysics · Physics 2009-11-07 D. Maurin , M. Casse , E. Vangioni-Flam

L\'{e}vy walk is a popular and more `physical' model to describe the phenomena of superdiffusion, because of its finite velocity. The movements of particles are under the influences of external potentials almost at anytime and anywhere. In…

Statistical Mechanics · Physics 2021-02-03 Yao Chen , Weihua Deng

The existence of cosmic ray particles up to the ultra-high energy limit (> 10^20 eV) is now beyond any doubt. The detection of cosmic particles with such energies imposes a challenge for the comprehension of their sources and nature. On one…

L\'evy flights and L\'evy walks serve as two paradigms of random walks resembling common features but also bearing fundamental differences. One of the main dissimilarities are discontinuity versus continuity of their trajectories and…

Statistical Mechanics · Physics 2017-05-09 Bartlomiej Dybiec , Ewa Gudowska-Nowak , Eli Barkai , Alexander A. Dubkov

An analysis of arrival directions of extensive air showers generated by cosmic rays in the PeV energy range and registered with the EAS MSU and EAS-1000 Prototype arrays reveals a considerable number of regions of excessive flux of cosmic…

High Energy Astrophysical Phenomena · Physics 2015-05-13 M. Yu. Zotov , G. V. Kulikov

The origin of the highest-energy cosmic rays remains a mystery. The lack of a high energy cutoff in the cosmic ray spectrum together with an apparently isotropic distribution of arrival directions have strongly constrained most models…

Astrophysics · Physics 2010-12-03 A. V. Olinto