A Public Set of Synthetic Spectra from Expanding Atmospheres for X-Ray Novae. I. Solar Abundances
Abstract
X-ray grating observations have revealed great detail in the spectra of novae in the Super Soft Source (SSS) phase. Notable features in the SSS spectra are blueshifted absorption lines, P-Cygni line profiles, and the absence of strong ionization edges, all of which are indicators of an expanding atmosphere. We present, and make publicly available, a set of 672 wind-type (WT) synthetic spectra, obtained from the expanding NLTE SSS models introduced in Van Rossum & Ness with the PHOENIX stellar atmosphere code. The set presented in this paper is limited to solar abundances with the aim to focus on the basic model parameters and their effect on the spectra, providing the basis upon which abundance effects can be studied using a much bigger non-solar set in the next paper in this series. We fit the WT spectra to the five grating spectra taken in the SSS phase of nova V4743 Sgr 2003 as an example application of the WT models. Within the limits of solar abundances we demonstrate that the following parameters are constrained by the data (in order of decreasing accuracy): column density N H, bolometric luminosity L bol, effective temperature T eff, white dwarf radius R, wind asymptotic velocity v ∞, and the mass-loss rate \dot{M}. The models are also sensitive to the assumed white dwarf mass M WD but the effect on the spectra can largely be compensated by the other model parameters. The WT spectra with solar abundances fit the data better than abundance optimized hydrostatic models.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2012
- DOI:
- 10.1088/0004-637X/756/1/43
- arXiv:
- arXiv:1205.4267
- Bibcode:
- 2012ApJ...756...43V
- Keywords:
-
- novae;
- cataclysmic variables;
- radiative transfer;
- stars: individual: V4743 Sgr;
- X-rays: stars;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Accepted for publication in ApJ