Physics of nova outbursts: Theoretical models of classical nova outbursts with optically thick winds on 1.2~M_ and 1.3~M_ white dwarfs

We present time-dependent nova outburst models with optically thick winds for a 1.2 and 1.35 M_ white dwarfs (WDs) with a mass accretion rate of 5 × 10⁻⁹~M_ yr⁻¹ and for a 1.3 M_ WD with 2 × 10⁻⁹~M_ yr⁻¹. The X-ray flash occurs 11 days before the optical peak of the 1.2 M_ WD and 2.5 days before the peak of the 1.3 M_ WD. The wind mass loss rate of the 1.2 M_ WD (1.3 M_ WD) reaches a peak of 6.4 × 10⁻⁵~M_ yr⁻¹ (7.4 × 10⁻⁵~M_ yr⁻¹) at the epoch of the maximum photospheric expansion with the lowest photospheric temperature of log Tₚₕ (K)=4.33 (4.35). The nuclear energy generated during the outburst is lost in a form of radiation (61% for the 1.2 M_ WD; 47% for the 1.3 M_ WD), gravitational energy of ejecta (39%; 52%), and kinetic energy of the wind (0.28%; 0.29%). We found an empirical relation for fast novae between the time to optical maximum from the outburst tₚₑₐₖ and the expansion timescale τₑₓₚ at $t=0$. With this relation, we are able to predict the time to optical maximum tₚₑₐₖ from the ignition model (at $t=0$) without following a time-consuming nova wind evolution.