Structure of magnetic fields generated by galactic dynamos

Makoto Tosa; Masashi Chiba

doi:10.1080/03091929008219879

Structure of magnetic fields generated by galactic dynamos

Makoto Tosa, Masashi Chiba

SCI - Astronomy

Research output: Contribution to journal › Article › peer-review

2 Citations (Scopus)

Abstract

We investigated global axisymmetric (m = 0) and nonaxisymmetric (m=1) modes of magnetic fields generated by the galactic dynamo including the α2-dynamo. The α2-dynamo is responsible for the field generation in the central region of galaxies where the shear of galactic rotation is weak (e.g. MS1). The highest growth rate of m= 1 modes is always smaller than that of m=0 modes; thus m= 1 modes of the standard galactic dynamo cannot explain the dominance of the bisymmetric fields in spiral galaxies. Radial extent of each m=1 mode is too narrow to reproduce the observed bisymmetric structure extending over a disk.

Original language	English
Pages (from-to)	147-157
Number of pages	11
Journal	Geophysical and Astrophysical Fluid Dynamics
Volume	50
Issue number	1-3
DOIs	https://doi.org/10.1080/03091929008219879
Publication status	Published - 1990 Jan

Keywords

Dynamos
galaxies
magnetohydrodynamics

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10.1080/03091929008219879

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title = "Structure of magnetic fields generated by galactic dynamos",

abstract = "We investigated global axisymmetric (m = 0) and nonaxisymmetric (m=1) modes of magnetic fields generated by the galactic dynamo including the α2-dynamo. The α2-dynamo is responsible for the field generation in the central region of galaxies where the shear of galactic rotation is weak (e.g. MS1). The highest growth rate of m= 1 modes is always smaller than that of m=0 modes; thus m= 1 modes of the standard galactic dynamo cannot explain the dominance of the bisymmetric fields in spiral galaxies. Radial extent of each m=1 mode is too narrow to reproduce the observed bisymmetric structure extending over a disk.",

keywords = "Dynamos, galaxies, magnetohydrodynamics",

author = "Makoto Tosa and Masashi Chiba",

note = "Funding Information: We would like to express our thanks to Dr M. Krause for her helpful comments and useful information. Numerical computations were carried out on the ACOS 2000 system at the Computer Center of Tohoku University. This work was supported in part by the Scientific Research Fund of the Ministry of Education, Science, and Culture (61540173 and 63540184).",

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language = "English",

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pages = "147--157",

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T1 - Structure of magnetic fields generated by galactic dynamos

AU - Tosa, Makoto

AU - Chiba, Masashi

N1 - Funding Information: We would like to express our thanks to Dr M. Krause for her helpful comments and useful information. Numerical computations were carried out on the ACOS 2000 system at the Computer Center of Tohoku University. This work was supported in part by the Scientific Research Fund of the Ministry of Education, Science, and Culture (61540173 and 63540184).

PY - 1990/1

Y1 - 1990/1

N2 - We investigated global axisymmetric (m = 0) and nonaxisymmetric (m=1) modes of magnetic fields generated by the galactic dynamo including the α2-dynamo. The α2-dynamo is responsible for the field generation in the central region of galaxies where the shear of galactic rotation is weak (e.g. MS1). The highest growth rate of m= 1 modes is always smaller than that of m=0 modes; thus m= 1 modes of the standard galactic dynamo cannot explain the dominance of the bisymmetric fields in spiral galaxies. Radial extent of each m=1 mode is too narrow to reproduce the observed bisymmetric structure extending over a disk.

AB - We investigated global axisymmetric (m = 0) and nonaxisymmetric (m=1) modes of magnetic fields generated by the galactic dynamo including the α2-dynamo. The α2-dynamo is responsible for the field generation in the central region of galaxies where the shear of galactic rotation is weak (e.g. MS1). The highest growth rate of m= 1 modes is always smaller than that of m=0 modes; thus m= 1 modes of the standard galactic dynamo cannot explain the dominance of the bisymmetric fields in spiral galaxies. Radial extent of each m=1 mode is too narrow to reproduce the observed bisymmetric structure extending over a disk.

KW - Dynamos

KW - galaxies

KW - magnetohydrodynamics

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DO - 10.1080/03091929008219879

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VL - 50

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EP - 157

JO - Geophysical and Astrophysical Fluid Dynamics

JF - Geophysical and Astrophysical Fluid Dynamics

IS - 1-3

ER -

Structure of magnetic fields generated by galactic dynamos

Abstract

Keywords

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