On the Nature of the X-Ray Emission from 1E 1024.0-5732/Wack 2134: The First X-Ray--selected Wolf-Rayet Star
Abstract
We report on a ROSAT Position-Sensitive Proportional Counter (PSPC) observation of the X-ray source 1E 1024.0-5732. The optical identification with the emission-line star Wackerling 2134 is confirmed, but we do not find any evidence of the periodic pulsations at 61 ms which were previously reported in its X-ray flux. On the basis of the new timing and spectral results, a reexamination of the old X-ray and optical data, and a new optical spectrum, we propose that this source is a new Wolf-Rayet star of type WN6. The high level of X-ray emission hints at the presence of a binary companion to Wack 2134. This could be either an accreting compact object or a massive OB star, in which case the X-rays would be produced in the colliding winds of the two stars. The small equivalent widths of the Wolf-Rayet star emission lines strongly support the O-star companion hypothesis. If this scenario is confirmed, Wack 2134 would be the first case of an X-ray-selected Wolf-Rayet star.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 1994
- DOI:
- 10.1086/173943
- Bibcode:
- 1994ApJ...424..943M
- Keywords:
-
- Light (Visible Radiation);
- O Stars;
- Stellar Winds;
- Visible Spectrum;
- Wolf-Rayet Stars;
- X Ray Astronomy;
- X Ray Binaries;
- X Rays;
- Astronomical Catalogs;
- Goodness Of Fit;
- Heao 2;
- Hubble Space Telescope;
- Maximum Likelihood Estimates;
- Proportional Counters;
- Rosat Mission;
- Stellar Luminosity;
- Astrophysics;
- STARS: BINARIES: CLOSE;
- STARS: INDIVIDUAL ALPHANUMERIC: 1E 1024.0-5732;
- STARS: WOLF-RAYET;
- X-RAYS: STARS