The peculiar outburst of the star baptized
Sakurai’s Object (SO) is a conceivable example of
a late He shell flash in a post-AGB object. The
new source of nuclear energy forces such objects
toward high luminosities and eventually low
effective temperatures; they cross the HR diagram
in a comparable fashion as FG Sge did in the past
- i.e., they move noticeably on the HR diagram on
human timescales. From monitoring campaigns of SO
during the last year, first estimates of its
cooling rate were derived and in particular cyclic
light variability was established. We present
first results from attempts to model stellar
envelopes appropriate for SO. As we hypothesize
the light variability to be attributable to
stellar pulsations, we aim at constraining the
basic stellar parameters based on stability
analyses of our envelope models. Radial,
nonadiabatic stability computations provided
predictions of the modal content which should be
observable as SO evolves. The particular
components in such mode spectra of SO as they are
to appear in the coming years should indeed help
to constrain basic stellar parameters such as mass
and luminosity.
Sakurai’s Object: Constraints from its
Variability?
