MG12 - Talk detail |
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Participant |
Stergioulas, Nikolaos | |
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Institution |
Aristotle University of Thessaloniki - Department of Physics - Thessaloniki - - Greece | |
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Session |
Talk |
Abstract |
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ANM5 |
Relativistic Simulations of MHD Oscillations in Magnetars |
We present 2D simulations of Alfven oscillations in magnetars, using the anelastic approximation to general relativistic MHD. We confirm the existence of two families of QPOs, with harmonics at integer multiples of the fundamental frequency and explain the observed continuum in Alfven frequencies with a semi-analytic approach, which allows for a clear interpretation of the QPOs as corresponding to turning points of the continuum. Furthermore, we construct empirical relations for the QPO frequencies and compare them to observations of QPOs in giant flares from known Soft Gamma Repeaters. Our magnetar QPO model places an upper limit to the mean surface strength of the magnetic field of several times 10^15 G. |
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ANM5 |
Oscillations of Rotating Relativistic Stars: Recent Developments |
The dynamics of nascent, rotating neutron stars is dominated by several oscillation modes, some of which may become unstable. We review recent developments in computing oscillation modes for rapidly rotating relativistic stars and discuss their astrophysical significance. |