Discovery of a 7 Second Anomalous X-ray Pulsar in the Distant Milky Way

Abstract

¡∼ >∼X − rayX − raysneutronstarNSsupernovaremnantγ-ray γ-rays RCW1.5pt103 Einstein Einstein RXTE RXTE ASCA ASCA ROSAT ROSAT Mar 28 1998 Gotthelf & Vasisht Discovery of a 7 s X-ray Pulsar document Discovery of a 7 Second Anomalous X-ray Pulsar in the Distant Milky Way E. V. Gotthelf1 NASA/Goddard Space Flight Center, Greenbelt, MD 20771 gotthelf@gsfc.nasa.gov G. Vasisht Jet Propulsion Laboratory, California Institute of Technology MS 171-113, Pasadena, CA 91109 gv@astro.caltech.edu 1Universities Space Research Association abstract We report the serendipitous discovery of a 7-s X-ray pulsar using data acquired with the Advanced Satellite for Cosmology and Astrophysics (). The pulsar is detected as an unresolved source located towards a region of the Galactic plane (l, b ' 29.5, 0.08) that coincides with an overdensity of star-formation tracers. The signal suffers tremendous foreground absorption, equivalent to NH ' 10 cm−2; the absorption correlates well with a line-of-sight that is tangential to the inner spiral arms and the 4-kpc molecular ring. The pulsar is not associated with any known supernova remnants or other cataloged objects in that direction. The near sinusoidal pulse (period P ' 6.9712) is modulated at 35% pulsed amplitude, and the steep spectrum is characteristic of hot black-body emission with temperature kT ∼ 0.65 keV. We characterize the source as an anomalous X-ray pulsar (AXP).

Cite this paper

@inproceedings{Gotthelf1998DiscoveryOA, title={Discovery of a 7 Second Anomalous X-ray Pulsar in the Distant Milky Way}, author={Eric V. Gotthelf}, year={1998} }