(cba:news) new year, new stars

Joe Patterson jop at astro.columbia.edu
Sun Jan 5 09:17:08 EST 2003

Dear CBAers,

Whew, two weeks away from classes and burrowing into the treasures of CBA
data - what a great break it has been!  We're readying a paper on new
superhump and orbital periods of ten dwarf novae, or twenty if John
Thorstensen lets me pollute the "pure" spectroscopic Porbs with filthy
things like photometry.  About a month away I reckon.

In the never-ending struggle for control of the CV sky, the edge has swung
decidedly to the south.  The campaign on EC0422-20 has been superb with
Berto and Robert Rea performing their usual yeoman service, and a strong
supporting cast (Greg Bolt, David Messier, Jerry Foote, Lew Cook, Tom
Richards, and especially Jeff Robertson).  The star has very powerful
negative superhumps at 3.32 hrs, plus the nodal signal that is typical of
these stars.  Since it is also 12th magnitude, it's a star that's
likely to teach us something... and we should keep covering it
sporadically for YEARS - so we can follow the (probably drifting) O-C and
see how period and amplitude are affected by luminosity state.  This is
likely to become the prototype negative superhumper, if we can keep the

But that's for sporadic coverage, not for the all-night-all-week-all-month
style that is our usual modus operandi.  For the latter, the best southern
objects right now are:

1. NSV 10934, at 18h 40m 52.4s -83d 43' 9.5" (2000).  It's now about 12th
mag, but seems to fade to 15th.  A just announced SU UMa star with freshly
born superhumps.  At this brightness level, this is a star that should
command our immediate (and prolonged) attention.  Long time series for as
long as the star stays above your horizon.  (Ha, ha, ha.)

2. EC 05565-5935, a 14th mag star at 05h 56m 32.8s -59d 35' 40" (1950,
please note unusual epoch).  The next in our series of studies of
Edinburgh-Cape novalikes.  At 14th mag and with Porb apparently near 3.4
hr, it definitely looks like one of our family.


Adios to EC0422-20, except for the occasional run to track phase.

FS Aur is another star that should remain on the menu for occasional runs
mainly to track phase.  It continues to stump us - unrelated spectroscopic
and photometric periods.  Curses.  To evaluate the stability of Pphot, we
need to track the phase with a 3-4 hour time series every couple of weeks.

V1062 Tau.  Oh, fiddlesticks.  What a tough star.  Eve Armstrong just
obtained many long runs on it from the 1.3 m.  We learned that the
published period is aliased... but the periods are uncomfortably long and
the star is faint and gets ravaged by the Moon a lot.  I was surprised
that Cap'n Bob's recent data was of such high quality - revealed about as
much as the 1.3 m.  But I tend to think that was a rare confluence of luck
(skies) and skill (experience).  Plus maybe the star was having a good
day.  I think we should take this star off the CBA menu.

The flashy new target is DW Cnc, in the Downes-Shara catalogue.  It's
doubly-periodic in the spectroscopy and triply periodic in the
photometry.  All of 'em stable.  Whooppee-do!  An obvious new DQ Her
star.  Let the good times, and delta mags, roll.

The other new targets for coverage are BZ Cam (very bright, good for
smallscopes but you need *long* time series) and PQ Gem.  We've taken
cracks at 'em in the past, with results that tantalized but didn't quite
deliver the goods.  I especially hope the Euros will appreciate that dec
of BZ Cam, and get some timeseries which will inspire gringos and other
borealites to match 'em!

January... that means Rookie of the Year awards.  There were two
candidates strong enough to win in a typical year: Berto Monard and David
Messier.  Berto's light curves would obviously have won on pure merit, but
some committee members felt that his amateur and rookie status were both
questionable (professional scientist, famous visual observer).  In what
might be described as an anti-Ichiro effect (rumor has it that the
committee included some baseball fans), Messier won in a close vote.

The actual prize is still a closely guarded secret.


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