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Magnetic Field Limit on SGR 1900+14

R. E. Rothschild·D. Marsden·R. E. Lingenfelter
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Abstract

We measured the period and spin-down rate for SGR 1900+14 during the quiescient period two years before the recent interval of renewed burst activity. We have shown that the spin-down age of SGR 1900+14 is consistent with a braking index of ~1 which is appropriate for wind torques and not magnetic dipole radiation. We have shown that a combination of dipole radiation, and wind luminosity, coupled with estimated ages and present spin parameters, imply that the magnetic field for SGR 1900+14 is less than 6 x 10^13 G and that the efficiency for conversion of wind luminosity to x-ray luminosity is <2%.

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R. E. Rothschild, D. Marsden, R. E. Lingenfelter. 1999-11-13. Magnetic Field Limit on SGR 1900+14. https://arxiv.org/abs/astro-ph/9911238

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