Baltic Astronomy, vol. 20, 275–280, 2011 HIGH-QUALITY FAST QPOs FROM MAGNETARS: AN ELECTRIC CIRCUIT MODEL
نویسندگان
چکیده
An interpretation of high-frequency (20–2400 Hz) fast quasiperiodic oscillations of magnetars in terms of an equivalent electric circuit is given. Observed periods and the very high quality of quasi-periodic oscillations are explained. The oscillation source is represented as a hot electron-positron plasma in a ‘trapped fireball’, a system of current-carrying magnetic loops of various sizes. The physical parameters of a ‘trapped fireball’ in the flare of SGR 1806-20 (2004 December 27) are estimated.
منابع مشابه
SGR1806-20: evidence for a superstrong Magnetic Field from Quasi Periodic Oscillations
Fast Quasi-Periodic Oscillations (QPOs, frequencies of ∼ 20−1840 Hz) have been recently discovered in the ringing tail of giant flares from Soft Gamma Repeaters (SGRs), when the luminosity was of order 1041 − 1041.5 erg/s. These oscillations persisted for many tens of seconds, remained coherent for up to hundreds of cycles and were observed over a wide range of rotational phases of the neutron ...
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