Discovery of the Slowest X-Ray Pulsar in the SMC, AX J0049.5-7323, with ASCA
Abstract
The discovery of coherent pulsations with ASCA from an X-ray source, AX J0049.5-7323, is reported. The barycentric period was determined to be 755.5 +/- 0.6 s, which is the longest among X-ray pulsators in the SMC. The X-ray spectrum has been found to be unchanged through ASCA observations, with a photon index of ~ 0.8 and a luminosity of ~ 5 x 1035 erg s-1 (0.7-10 keV). Archival data of the Einstein and the ROSAT satellites indicate that the flux has been <~ 10-12 erg s-1 cm-2 (<~ 5 x 1035 erg s-1) for over 20 years and exhibits a variability with a factor of >~ 10. We argue that AX J0049.5-7323 is an X-ray pulsar with a Be star companion.
- Publication:
-
Publications of the Astronomical Society of Japan
- Pub Date:
- December 2000
- DOI:
- 10.1093/pasj/52.6.L73
- arXiv:
- arXiv:astro-ph/0011260
- Bibcode:
- 2000PASJ...52L..73Y
- Keywords:
-
- PULSARS: INDIVIDUAL (AX J00495-7323);
- STARS: EMISSION-LINE;
- BE;
- STARS: NEUTRON;
- X-RAYS: STARS;
- Astrophysics
- E-Print:
- 4 pages, 4 figures, to be published in PASJ. Also available at http://www-cr.scphys.kyoto-u.ac.jp/member/jun/job/