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Malc et al,
At the moment they're just personal emails between Steve and myself - having said that I've no problem sharing....
I get the feeling he really want's to work through the ARAS forum - like he did for the Nova Del....
Let me know if you want copies of the current emails.....
This is his reply re the magnitude fluctuations:
"" The most interesting feature of the light curve, I think, is its
similarity to a few other classical systems (historical ones) that have
shown "oscillations" during the peak and early stages of decline. The
one that is rather striking is a relatively recent nova, V5588 Sgr
2009. It was quite faint, there are VERY few spectra, but the two
Christian managed to catch are similar to the V1369 Cen spectra now
and, more to the point, don't show any hint of Ne so it was likely a CO
type. The only spectra were from the optically thick stage (at least
the only ones I can see, Fred Walter has sequestered the others from
SMARTS although I';ve seen them, low resolution but enough to be
interesting in the optically thin stages). These oscillations, if you
extend the light curve to months instead of weeks, seem to increase in
their intervals. This was seen,. for instance, for GK Per 1901
although not realized at the time, and with the earlier optical
(visual) data you can never be quite sure. There were also multiple
peaks in other classical systems, CP Pup for instance, that were
actually relatively fast. And then there's T Pyx, everything odd a
nova can do was and is done by this one. But the interesting feature
of its light curve is that there isn't this same sort of quasi-periodic
behavior in the multiple peaks, they seem to come on a timescale but
not so nearly regularly.
What this is, at this stage, would require too much speculation. But
being a theorist by training, there are two clear possibilities (still
speculative). The thermonuclear source could still be exciting
ejections, but on this timescale it's very hard to believe unless it's
an indication of intermittent accretion, again something that's hard to
compute and harder to credit. Or there could be -- already -- a
thermal instability of the WD that's causing a variable illumination of
the ejecta as the effective temperature changes. This is more
reasonable, the timescales are kind of ling but not impossible, but
that's something I'm still working out. It's been suggested that after
the ejection event there is a relaxation of the WD so perhaps that's
going on here and the angle of viewing is favoring a view of the
phenomenon. The objection is that this is a rare thing, while other
novae would be expected to show it unless it's something specific to
the WD mass.
Anyway, these are still idle thoughts in the early stages. One should
remember that although the nova event is brief in normal astronomical
senses, the behavior is individual (even with regularities) and
patience is always a virtue.
I hope this helps. ""
We really need to organise/ arrange with Francois and the ARAS forum to collect and publish the data as well as a running commentary from Steve.
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