(cba:news) stars for the new season

Joe Patterson jop at astro.columbia.edu
Thu Dec 2 10:43:02 EST 2004


Dear CBAers,

Time for a major overhaul of targets!  TT Ari, ES Cet, and BO Cet are all
ready for retirement.  The data on TT Ari are quite extensive and need
another couple weeks' analysis; but I think I can see the main story
emerging: a healthy apsidal superhump (at worb-W, where W is the putative
precession frequency), with at least one sideband present (2worb-W).  The
ES Cet and BO Cet data firm up the long-term ephemerides - so those stars
can be left till next year.  V364 Peg is also ready for retirement - the
superoutburst is (long since) over.

It's a fine season for some new novalikes.  FY Per and AH Men are prime
northern and southern targets, and plenty bright for all conditions.  I'm
a little worried about the entertainment factor in FY Per, though.  It's
really been a mystery star for us - sometimes with no significant
variability, other times sprouting a 1.5 hr period (anomalous since
Pspec=6 hr).  We just need to study it more!  But I realize that flat
light curves aren't too interesting... and dunno what the star will do, of
course.  Anyway, here are 2 other northern targets of high interest:

FS Aur. You bet. Another mystery, much like FY Per except that the
periodic signal and flickering in the star are reliably present, which
makes it more interesting to observe.  A good one for the best nights,
since it's a lot fainter.

BZ Cam. A novalike with waves in the light curve near Porb, but we just
haven't managed to pin down the period(s?).  Our last major effort was 10
years ago - time to get it right this time!

I reckon these three targets to be of about equal priority.  Remember,
though, that long nights are *greatly* advantageous for our period-finding
enterprise - so it's generally a good idea to adopt one and stick with it.

In the south, it's AH Men and AH Pic (EC0556-5935).  No periodic signals
seen in the latter during 2002/3, but they did show up in the SAAO data,
and they should be easy pickings for us!  Could be a very interesting
superhumper, well worth a 2-week campaign.  AH Men should be on our list
for a few months, with its impressively intricate (and varying) array of
superhump signals.  (Remember, AH Men has an unwanted companion 3 arcsec
away, so you're going to have to deal with that - presumably by cleanly
including it in aperture photometry.

For *short* observations, the DQ Hers remain good: AO Psc, V405 Aur, BG
CMi.

Happy observing!

joe




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