A stochastic simulation of the propagation of Galactic cosmic rays reflecting the discreteness of cosmic ray sources age and path length distribution

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[1] Miyake, S.

[2] Muraishi, H.

[3] Yanagita, S.

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| 1600年 / EDP Sciences卷 / 573期

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Aims. The path length distribution of Galactic cosmic rays (GCRs) is the fundamental ingredient for modeling the propagation process of GCRs based on the so-called weighted slab method. We try to derive this distribution numerically by taking into account the discreteness in both space and time of occurrences of supernova explosions where GCRs are suspected to be born. The resultant age distribution and ratio of B/C are to be compared with recent observations. Methods. We solve numerically the stochastic differential equations equivalent to the Parker diffusion-convection equation which describes the propagation process of GCR in the Galaxy. We assume the three-dimensional diffusion is an isotropic one without any free escape boundaries. We ignore any energy change of GCRs and the existence of the Galactic wind for simplicity. We also assume axisymmetric configurations for the density distributions of the interstellar matter and for the surface density of supernovae. We have calculated age and path length of GCR protons arriving at the solar system with this stochastic method. The obtained age is not the escape time of GCRs from the Galaxy as usually assumed; but the time spent by GCRs during their journey to the solar system from the supernova remnants where they were born. Results. The derived age and path length show a distribution spread in a wide range even for GCR protons arriving at the solar system with the same energy. The distributions show a cut-off at a lower range in age or path length depending on the energy of GCRs. These cut-offs clearly come from the discreteness of occurrence of supernovae. The mean age of GeV particles obtained from the distributions is consistent with the age obtained by direct observation of radioactive secondary nuclei. The energy dependence of the B/C ratio estimated with the path length distribution reproduces reliably the energy dependence of B/C obtained by recent observations in space. © ESO; 2015;

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共 44 条

[1] A stochastic simulation of the propagation of Galactic cosmic rays reflecting the discreteness of cosmic ray sources Age and path length distribution
Miyake, S.
Muraishi, H.
Yanagita, S.
ASTRONOMY & ASTROPHYSICS, 2015, 573
[2] The effects of discreteness of Galactic cosmic-ray sources
Taillet, R
Salati, P
Maurin, D
Vangioni-Flam, E
Cassé, M
ASTROPHYSICAL JOURNAL, 2004, 609 (01): : 173 - 185
[3] Origin of galactic cosmic rays: Sources, acceleration, and propagation
Ptuskin, V. S.
PROCEEDINGS OF THE 29TH INTERNATIONAL COSMIC RAY CONFERENCE, VOL 10, 2005, : 317 - 327
[4] AGE DISTRIBUTION OF GALACTIC COSMIC-RAYS
OWENS, AJ
ASTROPHYSICS AND SPACE SCIENCE, 1976, 40 (02) : 357 - 367
[5] Markov stochastic technique to determine galactic cosmic ray sources distribution
Ashraf Farahat
Journal of Astrophysics and Astronomy, 2010, 31 : 81 - 88
[6] Markov Stochastic Technique to Determine Galactic Cosmic Ray Sources Distribution
Farahat, Ashraf
JOURNAL OF ASTROPHYSICS AND ASTRONOMY, 2010, 31 (02) : 81 - 88
[7] Stochastic nature of Galactic cosmic-ray sources
Evoli, Carmelo
Amato, Elena
Blasi, Pasquale
Aloisio, Roberto
PHYSICAL REVIEW D, 2021, 104 (12)
[8] COSMIC-RAY PATH LENGTH DISTRIBUTION
ORMES, JF
BULLETIN OF THE AMERICAN PHYSICAL SOCIETY, 1978, 23 (04): : 562 - 562
[9] THE PATH-LENGTH DISTRIBUTION FOR GALACTIC COSMIC-RAY PROPAGATION - AN ENERGY-DEPENDENT DEPLETION OF SHORT PATH LENGTHS
GARCIAMUNOZ, M
GUZIK, TG
SIMPSON, JA
WEFEL, JP
ASTROPHYSICAL JOURNAL, 1984, 280 (01): : L13 - L17
[10] Diffuse Galactic γ-rays: Constraining Cosmic-Ray Origin and Propagation
I.V. Moskalenko
A.W. Strong
Astrophysics and Space Science, 2000, 272 : 247 - 254

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