rumblings in aquila

From: Joe Patterson <*jop_at_astro.columbia.edu*> Date: Fri, 19 Jul 2002 07:32:28 -0400 (EDT) · jop_at_astro.columbia.edu

Dear CBAers,

Well, the V603 Aql campaign has been going very well, with ~30 nights of
dense coverage.  Bob Rea, Neil Butterworth, and Berto have been the main
perpetrators.  The star shows a very strong positive superhump at 0.1449
days.  No hint of the negative superhump that dominated in 1992, and no
harmonics either.  Just a clear pure note, in the silence.

So that means we can forget V603 for the rest of the year.  On to other
targets!

In the north, I'm still earnestly hoping for good coverage of V533 Her
before it slinks into the western twilight.  It seems to have a decent
positive superhump (P=7.3% greater than Porb), but the data still don't
quite clinch the matter.  Another 2 weeks of coverage will, though, and
will define the period with high precision.

It's time to promote V1494 Aql (the 1999 nova) to a position of greater
honor.  The 2000-1 data show that this is basically a 3.23 hour eclipsing
binary.  But the "eclipses" are broad and shallow affairs, not at all like
CVs near quiescence.  I'd guess that each year (in this early post-nova
evolution) will bring a different waveform.  Near the celestial equator,
the star is well placed for essentially all CBAers. (19 23 05.4 +04 57 20
- 2000.0, chart on CBA website)

The other nearly equatorial target for campaign start-up is V1432 Aql
(right next to V1494 on the CBA chart page).  This star is famous in CV
history.  It was mistaken for a Seyfert galaxy for more than 10 years,
until an accurate X-ray position showed that it ain't the same.  In the
meantime, there was a flurry of papers purporting to explain how a
Seyfert galaxy could have a strict 3.3 hour period!

Anyway, it's a great target.  Though no barn-burner at V=14.8, it has a 1
mag variation and a deep eclipse... lots of nice signal to keep one
entertained.  I recommend it as co-equal with V1494 Aql.  You might want
to choose one and stay with it - that's usually the way to attain maximum
sensitivity in our period searches.

Finally, there's V1223 Sgr.  This one *is* a barn-burner at 13.3.  For one
reason or another, we've never gotten a really good campaign on it.  It's
a DQ Her star with a 13 minute period, and also an orbital period near 5
hours.  Let's nail it this time around.

A couple of weeks ago I sent off our paper on V442 Oph and RX1643+34, and
also tucked in the superhump results on V795 Her and DW UMa.  There was a
long author list  (Patterson, Fenton, Thorstensen, Harvey, Skillman,
Fried, Monard, O'Donoghue, Beshore, Martin, Niarchos, Vanmunster, Foote,
Bolt, Rea, Cook, Butterworth).  I'll send out copies to all authors today.
If you don't get it in a week, and are not overseas, feel free to
complain!  (Also, check the website; it may pop up there in a few days.)

   joe