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arXiv · 0810.4804

XMM-Newton observations of IGR J00291+5934: signs of a thermal spectral component during quiescence

Sergio Campana·Luigi Stella·Gianluca Israel·Paolo D'Avanzo
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Abstract

We present X-ray observations of the transient accretion-powered millisecond pulsar IGR J00291+5934 during quiescence. IGR J00291+5934 is the first source among accretion powered millisecond pulsars to show signs of a thermal component in its quiescent spectrum. Fitting this component with a neutron star atmosphere or a black body model we obtain soft temperatures (~64 eV and ~110 eV, respectively). As in other sources of this class a hard spectral component is also present, comprising more than 60% of the unabsorbed 0.5-10 keV flux. Interpreting the soft component as cooling emission from the neutron star, we can conclude that the compact object can be spun up to milliscond periods by accreting only <0.2 solar masses.

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Sergio Campana, Luigi Stella, Gianluca Israel, Paolo D'Avanzo. 2008-10-27. XMM-Newton observations of IGR J00291+5934: signs of a thermal spectral component during quiescence. https://doi.org/10.1086/595867

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