Type IA supernovae : theoretical light curves with a slow pre-maximum rise.
Abstract
We present theoretical light curve (LC) calculations which reproduce Type Ia supernovae with a slow pre-maximum rise (V maximum at ~ 20 days), like the recently observed SN 1990 N. We use the same input physics as in our previous work (Hoflich et al. 1991). In addition, both Thomson and line scattering has been included, which is crucial for reproducing the monochromatic LC. For the radiation transport the moment equations are solved. Our calculations are based on delayed detonation models in which the transition from a deflagration to a detonation occurs due to the pulsation of an exploding white dwarf. The interaction with an extended low density envelope created during the pulsation leads to a substantial redistribution of the kinetic energy inside the ejecta. The deceleration of the bulk of matter to <~ 10000 km/sec delays the rise time of the light curve from ~ 10 - 12 days, typical of delayed detonation models without a pulsation, to ~ 17 days, whereas the outer envelope acquires velocities of up to 30000 km/sec. The interaction with the extended ~10^10^ cm envelope is not specific to the delayed detonation scenario. To illustrate the effect we present the results of computations of the explosion of 1.2 M_sun_CO-WD inside an extended envelope of 0.8 M_sun_, which results in a rise time of ~ 25 days.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- January 1992
- Bibcode:
- 1992A&A...253L...9K
- Keywords:
-
- Gravitational Collapse;
- Light Curve;
- Stellar Physics;
- Supernova Remnants;
- Supernovae;
- Bolometers;
- Detonation;
- Stellar Oscillations;
- Ubv Spectra;
- White Dwarf Stars;
- Astrophysics