### Abstract

The distribution function of cosmic rays streaming perpendicular to the mean magnetic field in a turbulent medium is re-examined. Urch's (1977) discovery that, in quasilinear theory, the flux is due to particles at 90° pitch angle is discussed and shown to be consistent with previous formulations of the theory. We point out that this flux of particles at 90° cannot be arbitrarily set equal to zero, and hence we dismiss the alternative theory which proceeds from this premise. A further, basic inconsistency in Urch's new transport equation is demonstrated, and the connection between quasilinear theory and compound diffusion is discussed.

Original language | English (US) |
---|---|

Pages (from-to) | 507-513 |

Number of pages | 7 |

Journal | Astrophysics and Space Science |

Volume | 53 |

Issue number | 2 |

DOIs | |

State | Published - Feb 1978 |

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### ASJC Scopus subject areas

- Astronomy and Astrophysics
- Space and Planetary Science

### Cite this

**Cosmic-ray streaming perpendicular to the mean magnetic field - II : The gyrophase distribution function.** / Forman, M. A.; Jokipii, J. Randy.

Research output: Contribution to journal › Article

*Astrophysics and Space Science*, vol. 53, no. 2, pp. 507-513. https://doi.org/10.1007/BF00645037

}

TY - JOUR

T1 - Cosmic-ray streaming perpendicular to the mean magnetic field - II

T2 - The gyrophase distribution function

AU - Forman, M. A.

AU - Jokipii, J. Randy

PY - 1978/2

Y1 - 1978/2

N2 - The distribution function of cosmic rays streaming perpendicular to the mean magnetic field in a turbulent medium is re-examined. Urch's (1977) discovery that, in quasilinear theory, the flux is due to particles at 90° pitch angle is discussed and shown to be consistent with previous formulations of the theory. We point out that this flux of particles at 90° cannot be arbitrarily set equal to zero, and hence we dismiss the alternative theory which proceeds from this premise. A further, basic inconsistency in Urch's new transport equation is demonstrated, and the connection between quasilinear theory and compound diffusion is discussed.

AB - The distribution function of cosmic rays streaming perpendicular to the mean magnetic field in a turbulent medium is re-examined. Urch's (1977) discovery that, in quasilinear theory, the flux is due to particles at 90° pitch angle is discussed and shown to be consistent with previous formulations of the theory. We point out that this flux of particles at 90° cannot be arbitrarily set equal to zero, and hence we dismiss the alternative theory which proceeds from this premise. A further, basic inconsistency in Urch's new transport equation is demonstrated, and the connection between quasilinear theory and compound diffusion is discussed.

UR - http://www.scopus.com/inward/record.url?scp=2142737896&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=2142737896&partnerID=8YFLogxK

U2 - 10.1007/BF00645037

DO - 10.1007/BF00645037

M3 - Article

AN - SCOPUS:2142737896

VL - 53

SP - 507

EP - 513

JO - Astrophysics and Space Science

JF - Astrophysics and Space Science

SN - 0004-640X

IS - 2

ER -