Photon Bubbles in Accretion Discs
نویسنده
چکیده
We show that radiation dominated accretion discs are likely to suffer from a “photon bubble” instability similar to that described by Arons in the context of accretion onto neutron star polar caps. The instability requires a magnetic field for its existence. In an asymptotic regime appropriate to accretion discs, we find that the overstable modes obey the remarkably simple dispersion relation
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