Detection of supersoft X-ray emission from GQ Muscae nine years after a nova outburst
Abstract
GQ MUS (Nova Muscae 1983) was the first classical nova from which X-rays were detected during outburst1'2. Those Exosat observations were consistent with thermonuclear burning on the surface of a white dwarf emitting 1037-1038 erg s-1 at (3.0-3.5) × 105 K or with shocked circumstellar material emitting 1035 erg s-1 by thermal bremsstrahlung at 107 K. Here we report the detection by the Rosat satellite3 of GQ Mus as a very soft black-body-like source. If the observed X-ray flux is being radiated at the Eddington luminosity (1038 erg s-1) from a one-solar-mass white dwarf, its effective temperature must be ~3.5 × 105 K. We conclude that the white dwarf is burning hydrogen-rich material near its surface. GQ Mus is, however, the only one of 26 recent novae detected in the all-sky Rosat survey; this suggests that either most novae eject all their accreted material during outburst, or GQ Mus is now burning recently accreted material. GQ Mus appears identical to the supersoft X-ray sources CAL83, CAL87 and RX J0527.8-6954 (ref. 4), lending support to the suggestion that these sources are white dwarfs accreting and burning material from a companion5.
- Publication:
-
Nature
- Pub Date:
- January 1993
- DOI:
- 10.1038/361331a0
- Bibcode:
- 1993Natur.361..331O
- Keywords:
-
- Emission Spectra;
- Novae;
- Stellar Evolution;
- X Ray Sources;
- Black Body Radiation;
- Energy Spectra;
- Exosat Satellite;
- Stellar Envelopes;
- Stellar Models;
- Astrophysics