(cba:news) stars for the new year

Joe Patterson jop at astro.columbia.edu
Mon Dec 31 22:35:35 EST 2007

Dear CBAers,

Time to replace the menu of stars, as the Sun rolls eastward.

It's been a great 130 days for V455 And = HS2331+39.  The star is now down
to 15.2, still 1-1.5 mag above quiescence.  CBA observations have dwindled
quite a bit... but remember, it will likely be 10-30 years before we get
another eruption.  The star has many clocks, and tracking how each of them
manages to return to the quiescent state is our job!  (Well, it's humanity's
job, but we're in the best position to do it.)  So let's keep the faith on
Mister V455.

EF Tuc has received good coverage, mainly from Berto and David Moorhouse.
It looks like a tough nut to crack - there's a good candidate period near
3.5 hours, but this doesn't agree with well with last year's (indecisive)
result.  Some more analysis is needed here, so for now - and probably for
the year - we should sweep EF Tuc off the table.

Likewise for RX0232-37 (the outburst is over) and RX0407-06 (we have
enough).  Thanks to Greg Bolt's vigilance, we have two shiny new southern
superhumpers.  One is OT1112-35, a newly discovered dwarf nova... and the
other is FQ Mon, newly discovered with superhumps.  These are definitely
the stars of the week (and maybe a few) for southern observers. 

As soon as those dwarf novae fade from view, the best southern targets
become Swift 0732-13, V436 Car, and T Pyx.  BTW I know there are some
major T Pyx fans out there, and it seems that southern variable-star
records don't readily make it past the equator.  Can anyone tell me if
there is an observational record of steady fading in T Pyx since the
1966 outburst?  Has it been essentially steady since, say, 1968... or has
it faded some?
Just for the record, let's officially demote most other stars on the
"current targets" list.  V598 Pup, RX0022+61, CD Ind, RX1803+40, V Sge,
and RX1730-05... all gone for the year.

In the north, there's a bevy of DQ Her stars beckoning.  We finally got
enough on Aur = RX0636+35; but still want data on Lyn = sdss0804+51 and
Gem = rx0704+26.  PLus DW Cnc, which wants another season to complete the
long-term period study.

Finally, we're looking for eclipse timing data for T Aur.  Shows pretty
shallow eclipses, but a pretty fast rate of period change (I think), which
we'd like to ascertain for sure.

So that's the menu.  I apologize for my long silence; keeping up with
classes was a handful this fall... but it's the last hour of 2007, and
hope springs eternal.


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