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تسجيل مستخدم جديدCoherence constraints on physical parameters at bright radio sources and FRB emission mechanism
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Maxim Lyutikov
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We discuss physical constrains that observations of high brightness temperature coherent radio emission, with brightness temperatures as high as $T_b sim 10^{35}$ K, impose on the plasma parameters at relativistically moving astrophysical sources. High brightness temperatures imply a minimal plasma energy density at the source. Additional important constraints come from the fact that resonantly emitting particles lose most of their energy to non-resonant inverse Compton and synchrotron processes. We also interpret recent observations of high-to-low frequency drifting features in the spectra of repeating FRBs as analogues of type-III Solar radio bursts produced by reconnection plasma beams within magnetospheres of highly magnetized neutron stars.
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