2008/05/15 by A. Tiengo, P. Esposito, S. Mereghetti · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysical Phenomena and Observations #High-pressure geophysics and materials #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.1086/590078
5 pages (in emulate-apj style), 3 figures; accepted for publication in ApJ Letters
arxiv created 2008/05/15 · openalex publication_date 2008/06/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present the analysis of six XMM-Newton observations of the anomalous X-ray pulsar CXOU J010043.1–721134, the magnetar candidate characterized by the lowest interstellar absorption. In contrast with all the other magnetar candidates, its X-ray spectrum cannot be fitted by an absorbed power-law plus blackbody model. The sum of two (absorbed) blackbody components with kT 1 = 0.30 ± 0.02 keV and kT 2 = 0.7 ± 0.1 keV gives an acceptable fit, and the radii of the corresponding blackbody emission regions are R ∞ BB 1 = 12.1 + 2.1 −1.4 km and R ∞ BB 2 = 1.7 + 0.6 −0.5 km. The former value is consistent with emission from a large fraction of a neutron star surface, and given the well-known distance of CXOU J010043.1–721134, which is located in the Small Magellanic Cloud, it provides the most constraining lower limit to a magnetar radius ever obtained. A more physical model, where resonant cyclotron scattering in the magnetar magnetosphere is taken into account, has also been successfully applied to this source.