(cba:news) (cba:chat) V2069 Cyg/RX2123+42 - season over?

Joe Patterson jop at astro.columbia.edu
Sun Nov 28 15:53:39 EST 2010

Hi Tom et al.,

Yes, it's time to pull the plug on V2069 Cyg.  And I think on HT Cas as 
well (though I'm still studying that data, and might change my mind in a 
few days).  For an evening target, I strongly recommend XSS0056+4548, 
and I recommend it in BLUE or INFRARED light.  The star has two periods 
of about equal strength (0.03 mag), at 465 and 488 s.  It is *likely* 
that these signals have greatly different colors - and to test this, I 
recommend obtaining time series in B or I light (your choice).  Our past 
coverage in unfiltered ("pink") light is effectively about 6000 A - so 
either B or I light would give us some lever-arm on the color 
dependence.  We would like to go for 2-3 more weeks on this star until 
completing the season.  This paper is mostly finished, and just awaits 
that one result - a measure of the wavelength dependence of those two 

In the morning sky, I recommend picking up RX0704+26 ("Gem") again, now 
that we are nearing mid-season.  This paper is being refereed now, so in 
2-3 weeks we'll add in the new timings and send off the revision. 
Remember: it's a 480 s pulsation, and most of the power is at 240 s, so 
you'll need a cycle time of *not more than 60 s* to see the signal 
satisfactorily.  It's a 16th mag star, and you might think that's a 
stretch - but this is a VERY strong signal and really not difficult.

Time to end the campaign on V709 Cas too.

Finally, let's get going on Swift 0732.5-1331 (see Koji Mukai's website 
on intermediate polars for full information on this guy).  Exact 
position 07 32 37.64  -13 31 09; this is the NE star of a pair separated 
by 2" - it's fine if you include both stars.  The photometry's terrible, 
but the periodic signals jump right out!  (But a B filter might help.)


On 11/28/2010 1:26 PM, Tom Krajci wrote:
> Regarding V2069 Cyg/RX2123+42...is the season over?  I can get a little
> over two hours in the evening, but that will keep shrinking as the days
> pass.
> Thanks in advance,
> Tom Krajci
> Cloudcroft, NM

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