The anomalous ultraviolet spectrum of the AM HER star H 0538+608.
Abstract
The X-ray source H 0538 + 608, recently identified as an AM Her system, was observed with the IUE satellite and discovered to have a unique ultraviolet spectrum. The strong resonance emission lines commonly observed in the AM Her sources are present but with very unusual intensities: the C IV line is notably weak while N V strongly dominates, with an N V/C IV intensity ratio a factor of about 20 larger than the typical AM Her value. Such an anomaly is not satisfactorily explained in terms of orbital variability or differences in the ionization structure of the emitting region in the context of the present available photoionization models. A nonsolar chemical composition such as produced in nova-type outbursts cannot be excluded as a possible explanation. If confirmed, this would imply that nova outbursts can occur in strongly magnetized systems.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- December 1987
- Bibcode:
- 1987A&A...188...89B
- Keywords:
-
- Line Spectra;
- Stellar Mass Accretion;
- Ultraviolet Spectra;
- White Dwarf Stars;
- X Ray Sources;
- Iue;
- Novae;
- Spaceborne Astronomy;
- Stellar Composition;
- Stellar Models;
- Astrophysics