Magnetized stars with differential rotation and a differential toroidal field

Kotaro Fujisawa

    Research output: Contribution to journalArticle

    5 Citations (Scopus)

    Abstract

    We have succeeded in obtaining magnetized equilibrium states with differential rotation and differential toroidal magnetic fields. If an internal toroidal field of a protoneutron star is wound up from the initial poloidal magnetic field by differential rotation, the distribution of the toroidal magnetic field is determined by the profile of this differential rotation. However, the distributions of the toroidal fields in all previous magnetized equilibrium studies do not represent the magnetic winding by the differential rotation of the star. In this paper, we investigate a formulation of a differential toroidal magnetic field that represents the magnetic field wound up by differential rotation. We have developed two functional forms of differential toroidal fields which correspond to a v-constant and a j-constant field in analogy to differential rotations. As the degree of the differential becomes very high, the toroidal magnetic field becomes highly localized and concentrated near the rotational axis. Such a differential toroidal magnetic field would suppress the low-T/|W| instability more efficiently even if the total magnetic field energy is much smaller than that of a non-differential toroidal magnetic field.

    Original languageEnglish
    Pages (from-to)4016-s4024
    JournalMonthly Notices of the Royal Astronomical Society
    Volume450
    Issue number4
    DOIs
    Publication statusPublished - 2015 Apr 24

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    toroidal field
    magnetic field
    stars
    magnetic fields
    formulations

    Keywords

    • Stars: magnetic field
    • Stars: neutron
    • Stars: rotation

    ASJC Scopus subject areas

    • Space and Planetary Science
    • Astronomy and Astrophysics

    Cite this

    Magnetized stars with differential rotation and a differential toroidal field. / Fujisawa, Kotaro.

    In: Monthly Notices of the Royal Astronomical Society, Vol. 450, No. 4, 24.04.2015, p. 4016-s4024.

    Research output: Contribution to journalArticle

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