(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
ocillations.
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.)
Joe
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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