Gänsicke, B T

Schreiber, M R

English

Cape Town University OpenUCT

Irradiated accretion discs in post novae

We derive approximations for the $\dot M-\Sigma$ relation
(the so-called S-curves) of irradiated accretion discs from detailed
vertical structure calculations. Using these approximations, we
simulate the time-dependent behaviour of irradiated accretion discs in
dwarf novae and post novae. Our calculations show, in agreement with
Hameury et al. ([CITE]), that irradiation of the accretion disc should
cause small "echo" outbursts immediately following normal outbursts
-which contrasts with the observed dwarf nova light curves.
In addition, we calculate light curves of post nova systems where the
accretion disc is strongly irradiated by the hot white dwarf. We find
that the visual brightness of post novae gradually decreases
after the nova explosion as a result of the decreasing disc
irradiation from the continuously cooling white dwarf. The rate of
decline that we derive is in good agreement with the observations.
While we cannot exclude that additional effects may
contribute to the observed fading of post novae, e.g., a slow decrease
of the accretion rate, our calculations show that irradiation from the
cooling white dwarf plays an important rôle in the post nova
evolution

M. R. Schreiber

B. T. Gänsicke

EDP Sciences OAI-PMH repository (1.2.0)

https://open.uct.ac.za/bitstream/11427/35059/1/SchreiberMR_Irradiated_accr_2001.pdf

Irradiated accretion discs in post novae

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Cape Town University OpenUCT

EDP Sciences OAI-PMH repository (1.2.0)