Nonlocal (fractional-differential) model of cosmic ray transport in the interstellar medium
V.V. Uchaikin†a,
A.D. Erlykin‡b,
R.T. Sibatov§c aUl'yanovsk State University, ul. L. Tolstogo 42, Ulyanovsk, 432700, Russian Federation bLebedev Physical Institute, Russian Academy of Sciences, Leninsky prosp. 53, Moscow, 119991, Russian Federation cMoscow Institute of Physics and Technology (National Research University), Institutskii per. 9, Dolgoprudny, Moscow Region, 141701, Russian Federation
Mathematical modeling of the propagation of charged particles in the interstellar medium is a key aspect of the physics of cosmic rays. Improvements in measuring systems and enhancement of statistics via the results of extraterrestrial astronomy stimulate regular revisions of the computational models. Most of the currently used approaches are based on the local model of normal diffusion, which is attracting growing criticism. Reservations about this model arise because, first, it is in conflict with the relativistic principle of maximum speed and, second, it ignores specific spatial correlations in the properties of the turbulent interstellar medium. In this regard, in a previous review article by the first author (Physics-Uspekhi56 1074 (2013)), some arguments were adduced in favor of a nonlocal model of cosmic ray transport based on fractional differential operators. In this review, we continue expounding on the physical and mathematical properties of the fractional differential theory, with more attention focused on the procedure for incorporating the features of the interstellar medium into nonlocal operators. New results obtained in the framework of this approach are presented, compared, and discussed.
Keywords: cosmic rays, nonlocal model, fractional differential operator, turbulence, fractal medium, energy spectrum, anisotropy PACS:02.50.−r, 05.40.Fb, 98.70.Sa (all) DOI:10.3367/UFNe.2021.12.039118 URL: https://ufn.ru/en/articles/2023/3/a/ 001096987300001 2-s2.0-85182874677 2023PhyU...66..221U Citation: Uchaikin V V, Erlykin A D, Sibatov R T "Nonlocal (fractional-differential) model of cosmic ray transport in the interstellar medium" Phys. Usp.66 221–262 (2023)
Ginzburg V L, Syrovatskii S I The Origin Of Cosmic Rays (Oxford: Pergamon Press, 1964); Translated from Russian, Ginzburg V L, Syrovatskii S I Proiskhozhdenie Kosmicheskikh Luchei (Moscow-Leningrad: Izd. AN SSSR, 1963)
Osborne J L, Ptuskin V S Sov. Astron. Lett.13 413 (1987); Osborne J L, Ptuskin V S Pis’ma Astron. Zh.13 980 (1987)
Ptuskin V S, Soutoul A Astron. Astrophys.237 445 (1990)
Peebles P J E The Large-Scale Structure Of The Universe (Princeton, NJ: Princeton Univ. Press, 1980)
Uchaikin V, Sibatov R Fractional Kinetics In Space: Anomalous Transport Models (Singapore: World Scientific, 2018)
Dorman L I Cosmic Ray Interactions, Propagation, And Acceleration In Space Plasmas(Astrophysics and Space Science Library) Vol. 339 (Dordrecht: Springer, 2006)
Uchaikin V V, Korobko D A, Gismyatov I F Russ. Phys. J.40 711 (1997); Uchaikin V V, Korobko D A, Gismyatov I F Izv. Vyssh. Uchebn. Zaved. Fiz. (8) 7 (1997)
Parisi G, Frisch U A Turbulence And Predictability In Geophysical Fluid Dynamics And Climate Dynamics(Proc. of the Intern. School of Physics "Enrico Fermi", Course 88, Eds M Ghil, R Benzi, G Parisi) (Amsterdam: North-Holland, 1985)
Zelenyi L M, Milovanov A V Geomagn. Aeron.33 (4) 18 (1993)
Beck C, Schlögl F Thermodynamics Of Chaotic Systems: An Introduction (Cambridge: Cambridge Univ. Press, 1993)
Milovanov A V et al Cosmic Res.34 415 (1996); Milovanov A V et al Kosmich. Issled.34 451 (1996)
Badii R, Politi A Complexity: Hierarchical Structures And Scaling In Physics (Cambridge: Cambridge Univ. Press, 1997)
Meakin P Fractals, Scaling, And Growth Far From Equilibrium (Cambridge: Cambridge Univ. Press, 1998)
Harte D Multifractals: Theory And Applications (Boca Raton, FL: Chapman and Hall. CRC, 2001)
Frisch U Turbulence: The Legacy Of A.N. Kolmogorov (Cambridge: Cambridge Univ. Press, 1995); Translated into Russian, Frisch U Turbulentnost’. Nasledie A.N. Kolmogorova (Moscow: Fazis, 1998) p. 155
Gorbatskii V G Gazodinamicheskie Neustoichivosti V Astrofizicheskikh Sistemakh (Gas-Dynamic Instabilities In Astrophysical Systems) (St. Petersburg: Izd. Sankt-Peterburgskogo Univ., 1999)
Gorbatskii V G, Tarakanov P A Astrophysics41 53 (1998); Gorbatskii V G, Tarakanov P A Astrofiz.41 81 (1998)
Dudorov A E Sov. Astron.35 342 (1991); Dudorov A E Astron. Zh.68 695 (1991)
Berezinskii V S et al Astrophysics Of Cosmic Rays (Ed. V L Ginzburg) (Amsterdam: North-Holland, 1990); Translated from Russian, Berezinskii V S et al Astrofizika Kosmicheskikh Luchei (Ed. V L Ginzburg) (Moscow: Nauka, 1990)
Hayakawa S Cosmic Ray Physics: Nuclear And Astrophysical Aspects(Interscience Monographs and Texts in Physics and Astronomy) Vol. 22 (New York: Wiley-Interscience, 1969)
Kol’chuzhkin A M, Uchaikin V V Vvedenie V Teoriyu Prokhozhdeniya Chastits Cherez Veshchestvo (Introduction To The Theory Of The Transit Of Particles Through Matter) (Moscow: Atomizdat, 1978)
Dorman L I Eksperimental’nye I Teoreticheskie Osnovy Astrofiziki Kosmicheskikh Luchei (Experimental And Theoretical Foundations Of Astrophysics Of Cosmic Rays) (Moscow: Nauka, 1975)
Uchaikin V V, UchaikD V Obozrenie Priklad. Promyshlen. Matem.9 477 (2002)
Bohm D The Many Body Problem, Les Houches, Session 1958 (London: Wiley, 1959) p. 401; Translated into Russian, Bohm D Obshchaya Teoriya Kollektivnykh Peremennykh ((Moscow: Mir, 1964)
Bird G A Molecular Gas Dynamics (Oxford: Clarendon Press, 1976); Translated into Russian, Bird G A Molekulyarnaya Gazovaya Dinamika (Moscow: Mir, 1981)
Filippov B V, Il’Inskaya G B Sov. Phys. Dokl.10 915 (1966); Filippov B V, Il’Inskaya G B Dokl. Akad. Nauk SSSR164 768 (1965)
Lagutin A A, Raikin R I, Tyumentsev A G Izv. Altaiskogo Gos. Univ. (22) 6 (2004)
Lévy P Random Functions: General Theory With Special Reference To Laplacian Random Functions (Univ. Of California Publ. In Statistics, Vol. 1, No. 12) (Berkeley, CA: Univ. of California Press, 1953)
Lagutin A A, Uchaikin V V Proc. of the 27th Intern. Cosmic Ray Conf., 7-15 August 2001, Hamburg, Germany Vol. 5 Vol. 5 (Geneve: International Union of Pure and Applied Physics, 2001) p. 1900
Lagutin A A, Strelnikov D V, Tyumentsev A G Proc. of 27th Intern. Cosmic Ray Conf., Hamburg, Germany, 2001 Vol. 5 (Hamburg: Copernicus Gesellschaft, 2001)