Superradiance around rotating dilatonic black holes

Jun ichirou Koga, Keiichi Maeda

    Research output: Contribution to journalArticle

    12 Citations (Scopus)

    Abstract

    We consider a superradiance effect around rotating dilatonic black holes. We analyze two cases: one is an exact solution with the coupling constant α = 3, which effective action is reduced from the 5-dimensional Kaluza-Klein theory, and the other is a slowly rotating dilatonic black holes with arbitrary coupling constant. We find that there exists a critical value (α ∼ 1), which is predicted from a superstring model, and the superradiant emission rate with coupling larger than the critical value becomes much higher than the Kerr-Newman case (α = 0) in the maximally charged limit. Consequently, 4-dimensional primordial black holes in higher dimensional unified theories are either rotating but almost neutral or charged but effectively non-rotating.

    Original languageEnglish
    Pages (from-to)29-34
    Number of pages6
    JournalPhysics Letters B
    Volume340
    Issue number1-2
    DOIs
    Publication statusPublished - 1994 Dec 1

    ASJC Scopus subject areas

    • Nuclear and High Energy Physics

    Cite this

    Superradiance around rotating dilatonic black holes. / Koga, Jun ichirou; Maeda, Keiichi.

    In: Physics Letters B, Vol. 340, No. 1-2, 01.12.1994, p. 29-34.

    Research output: Contribution to journalArticle

    Koga, Jun ichirou ; Maeda, Keiichi. / Superradiance around rotating dilatonic black holes. In: Physics Letters B. 1994 ; Vol. 340, No. 1-2. pp. 29-34.
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