A full cycle in the evolution of a classical nova

A classical nova model was evolved through a complete cycle, i.e. accretion leading to cutburst, mass loss and again accretion, ending in another outburst, by means of an implicit Lagrangian hydrodynamic code, which included diffusion (concentration, pressure and thermal terms), as well as an extensive nuclear reactions network between 28 isotopes of C, N, O, F, Ne, Na, Mg and Al. The initial model was a 1.25 M C–O white dwarf (WD) and the accretion rate assumed was 10^–11 M/yr. For more details of this calculation, see Prialnik (1986).The accreted matter was assumed to have normal composition (X=0.70, Z=0.03). Nevertheless, due to diffusion and convection, a significant amount of core material was mixed into the accreted matter, raising Z by a factor of 10. The model's evolution closely resembled that of a fast nova eruption, with a peak bolometric luminosity of 2.9×10⁵ L, a time of decline by 3^m of 25 days, an ejected mass of 6.5×10^–6 M and a maximum velocity of 3800 km/sec.Paper presented at the IAU Colloquium No. 93 on Cataclysmic Variables, Recent Multi-Frequency Observations and Theoretical Developments, held at Dr. Remeis-Sternwarte Bamberg, F.R.G., 16–19 June, 1986.