Uniting the Quiescent Emission and Burst Spectra of Magnetar Candidates

Yujin E. Nakagawa; Atsumasa Yoshida; Kazutaka Yamaoka; Noriaki Shibazaki

doi:10.1093/pasj/61.1.109

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arXiv · 0710.3816

Uniting the Quiescent Emission and Burst Spectra of Magnetar Candidates

Yujin E. Nakagawa·Atsumasa Yoshida·Kazutaka Yamaoka·Noriaki Shibazaki

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Abstract

Spectral studies of quiescent emission and bursts of magnetar candidates using XMM-Newton, Chandra and Swift data are presented. Spectra of both the quiescent emission and the bursts for most magnetar candidates are reproduced by a photoelectrically absorbed two blackbody function (2BB). There is a strong correlation between lower and higher temperatures of 2BB (kT_LT and kT_HT) for the magnetar candidates of which the spectra are well reproduced by 2BB. In addition, a square of radius for kT_T (R_LT^2) is well correlated with a square of radius for kT_HT (R_HT^2). A ratio kT_LT/kT_HT ~ 0.4 is nearly constant irrespective of objects and/or emission types (i.e., the quiescent emission and the bursts). This would imply a common emission mechanism among the magnetar candidates. The relation between the quiescent emission and the bursts might be analogous to a relation between microflares and solar flares of the sun. Three AXPs (4U 0142+614, 1RXS J170849.0-400910 and 1E 2259+586) seem to have an excess above ~7 keV which well agrees with a non-thermal hard component discovered by INTEGRAL.

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Yujin E. Nakagawa, Atsumasa Yoshida, Kazutaka Yamaoka, Noriaki Shibazaki. 2009-04-10. Uniting the Quiescent Emission and Burst Spectra of Magnetar Candidates. https://doi.org/10.1093/pasj%2F61.1.109

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