(cba:news) TT Ari, V368 Peg, VX For

Joe Patterson jop at astro.columbia.edu
Sun Oct 11 07:14:38 EDT 2009

Dear CBAers,

As some of you know, TT Ari - one of the brightest of all CVs at V~10.9 
(normally) - has fallen off the table in the last few weeks.  It's now 
down around V=13.3 and dropping.  This is the first deep drop in many 
years, and will give us an opportunity to track the light curve 
photometrically before (somewhat), during, and after its minimum.  It's 
not a *sure* bet to be photometrically interesting, as the disk gets 
kinda faint... but we won't know till we look, and its beautiful 
placement in the October midnight sky couldn't be more cooperative.
Mainly a northern target, but I hope that we'll get some NZ-AU coverage 
too, since we have quite a vast Pacific-and-Asia longitude gap for 
northern targets.

Meanwhile, VX For continues to tantalize in the southern sky.  It's 
reeling off some echo outbursts, and we're now getting good coverage 
from AU (mainly Arto and Chris Stockdale), NZ (Bob Rea), and ZA (Berto).
As for superhumps... whew, I think the answer is no, but the analysis is 
tricky when the nightly light curves show these strong ramps.  That's 
the general expectation: after the main outburst is over, superhumps in 
dwarf novae tend to die, get weak, get sloppy... or some undecipherable 
combination.  The long-lived echoes support the idea that this is a very 
old dwarf nova, with a puny secondary; but only the actual mass ratio, 
still unknown, will severely test this idea.  Anyway, the star is worth 
following as long as it keep flashing the echoes (3 so far I think).

V368 Peg is staging a great show - some really handsome superhumps.  I'm 
just starting my analysis, but it seems likely this will be a showpiece 

It's time to end our long campaign on V455 And.  EXCEPT during Nov. 
9-17.  We have a Kitt Peak run on those dates, and will be able to time 
the very fast signals.  Supporting CBA photometry will be quite good then.

BW Scl continues to be a very good target -  a gold mine of periodic 
signals.  Our paper on this star is "mostly written", and has remained 
in that status for 5 years, even though I work a lot on it every year. 
I learn too much new every year.  So, realistically, I guess if you 
never send me any more data, I'll send the paper off quite soon.  And if 
you keep torturing me with new things, the paper will fatten up, 
improve... and stay imprisoned in my computer.  Which is better?

Happy observing!


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