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The Anomalous X-ray Pulsar 1E 1048.1-5937: Phase resolved spectroscopy with the XMM-Newton satellite

A. Tiengo·E. Goehler·R. Staubert·S. Mereghetti
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Abstract

We report on an observation of the Anomalous X-ray Pulsar 1E 1048.1-5937 performed with the XMM-Newton satellite. The phase averaged spectrum of 1E 1048.1-5937 is well described by the sum of a power law with photon index ~2.9 and a blackbody with temperature ~0.6 keV, without evidence for significant absorption or emission lines. The above spectral parameters do not vary during the phases corresponding to the broad pulse, while the off pulse emission shows a different spectrum characterized by a soft excess at energies below ~1.5 keV. The XMM-Newton observation and a re-analysis of archival BeppoSAX data, show that the spectral parameters and flux of 1E 1048.1-5937 did not change significantly during observations spanning the last four years. All the data are consistent with a 2-10 keV luminosity varying in the range ~(5-7) 10^33 erg/s (for a distance of 3 kpc).

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A. Tiengo, E. Goehler, R. Staubert, S. Mereghetti. 2001-11-20. The Anomalous X-ray Pulsar 1E 1048.1-5937: Phase resolved spectroscopy with the XMM-Newton satellite. https://doi.org/10.1051/0004-6361%3A20011718

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