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On the excitation of f-modes and torsional modes by magnetar giant flares

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 نشر من قبل Yuri Levin
 تاريخ النشر 2011
  مجال البحث فيزياء
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 تأليف Yuri Levin -




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Magnetar giant flares may excite vibrational modes of neutron stars. Here we compute an estimate of initial post-flare amplitudes of both the torsional modes in the magnetars crust and of the global f-modes. We show that while the torsional crustal modes can be strongly excited, only a small fraction of the flares energy is converted directly into the lowest-order f-modes. For a conventional model of a magnetar, with the external magnetic field of about 10^{15} Gauss, the gravitational-wave detection of these f-modes with advanced LIGO is unlikely.

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