Seed magnetic Fields Generated by Primordial Supernova Explosions |
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| Authors: | Oswaldo D Miranda Merav Opher & Reuven Opher |
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| Institution: | Instituto Astronômico e Geofísico —Universidade de São Paulo, Av. Miguel Stéfano 4200, São Paulo, 04301-904, SP, Brazil |
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| Abstract: | The origin of the magnetic field in galaxies is an open question in astrophysics. Several mechanisms have been proposed related, in general, to the generation of small seed fields amplified by a dynamo mechanism. In general, these mechanisms have difficulty in satisfying both the requirements of a sufficiently high strength for the magnetic field and the necessary large coherent scales. We show that the formation of dense and turbulent shells of matter, in the multiple explosion scenario of Miranda &38; Opher for the formation of the large-scale structures of the Universe, can naturally act as a seed for the generation of a magnetic field. During the collapse and explosion of Population III objects, a temperature gradient not parallel to a density gradient can naturally be established, producing a seed magnetic field through the Biermann battery mechanism. We show that seed magnetic fields ∼ 10−12–10−14 G can be produced in this multiple explosion scenario on scales of the order of clusters of galaxies (with coherence length L ∼ 1.8 Mpc) and up to ∼ 4.5 × 10−10 G on scales of galaxies ( L ∼ 100 kpc). |
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| Keywords: | magnetic fields galaxies: magnetic fields cosmology: theory early Universe large-scale structure of Universe |
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