Protogalactic Extension of the Parker Bound
نویسندگان
چکیده
We extend the Parker bound on the galactic flux F of magnetic monopoles. By requiring that a small initial seed field must survive the collapse of the protogalaxy, before any regenerative dynamo effects become significant, we develop a stronger bound. The survival and continued growth of an initial galactic seed field ≤ 10G demand that F ≤ 5 × 10(m/10 GeV) cmsecsr. For a given monopole mass, this bound is four and a half orders of magnitude more stringent than the previous ‘extended Parker bound’ [1], but is more speculative as it depends on assumptions about the behavior of magnetic fields during protogalactic collapse. For monopoles which do not overclose the Universe (Ωm < 1), the maximum flux allowed is now 8 × 10 −19 cm s sr, a factor of 150 lower than the maximum flux allowed by the extended Parker bound.
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