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GCRT J1745-3009 as a Transient White Dwarf Pulsar

Bing Zhang·Janusz Gil
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Abstract

A transient radio source in the direction of the Galactic Center, GCRT J1745-3009, exhibited 5 peculiar consecutive outbursts at 0.33 GHz with a period of 77.13 minutes and a duration of ~10 minutes for each outburst. It has been claimed to be the prototype of a hitherto unknown class of transient radio sources. We interpret it as a transient white dwarf pulsar with a period of 77.13 minutes. The ~10-minute flaring duration corresponds to the epoch when the radio beam sweeps our line of sight. The bursting epoch corresponds to the episodes when stronger sunspot-like magnetic fields emerge into the white dwarf polar cap region during which the pair production condition is satisfied and the white dwarf behaves like a radio pulsar. It switches off as the pair production condition breaks down.

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Bing Zhang, Janusz Gil. 2005-08-25. GCRT J1745-3009 as a Transient White Dwarf Pulsar. https://doi.org/10.1086/497428

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