VELA X-1 Pulse Timing. II. Variations in Pulse Frequency
Abstract
The pulsed X-ray emission of Vela X-1 during May 1978 and December-January 1978-1979 is investigated analytically on the basis of published satellite observations. The data are compiled in tables and graphs and discussed in detail, with reference to data for the entire 1975-1982 period. Variations in pulse frequency are identified on time scales from 2 to 2600 days; the lower nine octaves are characterized as white noise (or random walk in pulse frequency), while the longer-period variations are attributed to changes in neutron-star rotation rates.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1989
- DOI:
- 10.1086/167017
- Bibcode:
- 1989ApJ...336..376D
- Keywords:
-
- Eclipsing Binary Stars;
- Neutron Stars;
- Pulsars;
- Pulse Duration;
- X Ray Binaries;
- Astronomical Spectroscopy;
- Power Spectra;
- Stellar Mass Accretion;
- Astrophysics;
- PULSARS;
- STARS: NEUTRON;
- STARS: ROTATION;
- X-RAYS: BINARIES