(cba:news) december stars

Joe Patterson jop at astro.columbia.edu
Mon Dec 10 07:15:38 EST 2012


Dear CBAers,

Time for some changes of target.

Let's sweep V455 And and PX And off the stage.  The season's getting too
late.  Also V405 Aur: we have enough.  Also RX0524+42 = Paloma: we
have absoltely beautiful and quite long coverage (from Tom and Enrique),
which specify the enormously intricate period structure quite well!

There are a bunch of DQ Her stars which are now "late season", and hence
seasonal for an accurate period determination during 2012.  Here they are:
AO Psc, FO Aqr, V2069 cyg, V2306 Cyg, RX2123+42, and V1033 Cas.  We need
only a few observations of each, with each "observation" a 2+ hour time
series of decent quality.

Then there are mid-season stars of this type: BG CMi, MU Cam, WX Pyx,
Swift 0732-13, RX0636+35, RX0704+26, and PQ Gem.  Again, a 2+ hour time
series will generally accomplish the needed result (an accurate pulse
timing).  Except for PQ Gem (for which a V or g filter is very desirable),
white-light is OK.

Now for mid-season targets which will especially repay LONG time series.

1. WX Ari.  Now in a low state around 17-17.5.  No time-series studies in
any previous low state.  It could be mighty interesting.

2. V1294 Tau = "Tau 2".  We once observed it with TWO superhumps - positive
and negative.  But the signals were too weak to be 100% certain.  Still
well placed in December, and at +6 degrees, available to both hemispheres.

3. IM Eri.  Great southern target, and also for intrepid northerners (-20).
At 11.7, great target for small scopes or bright skies.  Another SW Sexer
(like 1 and 2).

4. ES Cet.  We need timings of its 9 minute signal.  Fun target with such
a clean signal.

5. V1159 Ori and DI Ma.  Keep the faith - they're going well!


        joe



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