Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-12-11
Astronomy and Astrophysics
Astrophysics
14 text pages, 12 figures
Scientific paper
10.1086/319387
Optical observations of nova V1974 Cygni (Cygni 1992), spanning a 4 year period, have been used to study its spectroscopic evolution. The data cover a wavelength range from $\sim 3200 - 8000$ \AA and follows the nebular evolutionary phase of the ejecta. We have modeled the integrated fluxes by means of the photoionization code CLOUDY. The models were run at a {\it fixed} abundance value for the most prominent elements (i.e. H, He, C, O, N, Ne, Fe, etc) over the entire time sequence. It is possible to constrain from this simple model some of the physical conditions of the gaseous emitting region, like temperature and density. Compared with previous studies of the gas abundances of the heavy elements, we found that smaller enhancements of S, N and Ar, and comparable values for O and Fe, are able to reproduce the observations. The time evolution of the surface temperature of the ionizing source and the high-ionization iron lines [Fe VII] 6087 \AA and [Fe X] 6374 \AA, is similar to what it is observed in the soft X-rays. The early line profiles can be reproduced using a simple kinematical model consisting of an equatorial ring and polar caps, expanding at a velocity of $\sim 1100$ km/s. This simple model also approximates the structure of the resolved shell observed by HST. Considering the complicated structure of the shell, the lack of well defined values of its gas density and our limited knowledge of the time evolution of the surface temperature of the photoionization source, the comparison between models and observations agrees remarkably well.
Garnavich Peter M.
Moro-Martín Amaya
Noriega-Crespo Alberto
No associations
LandOfFree
The Optical Spectroscopic Evolution of V1974 Cygni (Nova Cygni 1992) does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Optical Spectroscopic Evolution of V1974 Cygni (Nova Cygni 1992), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Optical Spectroscopic Evolution of V1974 Cygni (Nova Cygni 1992) will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-149080