(cba:news) CI Aquilae in particular (Joe Patterson) [2021-07-08T03:40:37Z]

Hi CBAers,

I just wanted to push CI Aquilae a little extra hard.  As you know, it's 
a recurrent nova, and the only RN which can answer the question: is the 
great oddity of T Pyx/IM Nor (Mv, dP/dt) due to the short P_orb, or due 
to some other effect special to RNe (e.g. extreme and frequent heating 
of the donor).  The really long-P_orb RNe are not appropriate for such a 
test, because giant stars will be heated much less strongly - i.e. their 
properties are probably determined by the whims of the donor, not any 
binary interaction.

It's an equatorial star well-placed for everyone.  The only catch is 
that you absolutely need a long run - at least 5 hours if possible. 
P_orb = 15 hours, so define the orbital wave, you need some decent 
fraction of that.  Maybe 4 hours is OK.  That will often yield a pretty 
boring light curve... but with other longitudes pitching in, it'll be 
much better.

July-August is totally the season for novae!  Southern guys of course, 
because of the rich pickings in Sco-Sgr... but also some in the north or 
 equatorial (V1974 Cyg, V1494 Aql, CI Aql, others).  As usual, it's 
best to pick a program star and beat on it faithfully for a few weeks. 
That's what makes these campaigns scientifically impactful.

joe
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