X-ray observations of the slowest known Be/X-ray pulsars RXJ0146.9+6121 and XPersei
Abstract
We present ASCA and ROSAT observations of the Be/X-ray binary pulsars RXJ0146.9+6121 and XPersei between 1994 and 1996. Measuring the neutron star spin period and X-ray luminosity of XPersei shows that the episode of low X-ray luminosity and monotonic spin-down since 1978 continued to at least August 1995. ASCA and ROSAT HRI observations of RXJ0146.9+6121 detected the pulsar with the longest known neutron star spin period at low luminosities after the X-ray outburst seen by EXOSAT in August 1984. The large spin period decrease seen between 1984 and 1993 has nearly stopped at a period of 1407.3s in February 1996. We discuss that the X-ray outburst behaviour of XPersei with respect to its Be star phase changes observed in the optical can be caused by an asymmetry in the matter distribution around the Be star.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- February 1998
- DOI:
- 10.48550/arXiv.astro-ph/9710138
- arXiv:
- arXiv:astro-ph/9710138
- Bibcode:
- 1998A&A...330..189H
- Keywords:
-
- STARS: EMISSION-LINE;
- BE;
- STARS: INDIVIDUAL: RXJ0146.9+6121;
- X PERSEI;
- STARS: NEUTRON;
- X-RAYS: STARS;
- Astrophysics
- E-Print:
- 6 pages, LaTex, 8 figures, Accepted for publication in A&