AO Piscium

From: Joe Patterson <*jop_at_astro.columbia.edu*> Date: Thu, 14 Oct 1999 04:42:48 -0700 (MST) · jop_at_astro.columbia.edu

Well, I did a little more analysis on AO Psc, whose 14-minute pulse is
booming away this year as it has not since discovery in 1980.

The coverage in North America is superb (mainly Dave West, Lew Cook, 
Cap'n Bob), and fine details of the pulse behavior are easily apparent.
As is the orbital signal at 6.70 c/d.

But there is a signal at lower frequency, not seen before but in the range
associated with a superhump.  This occurs at 5.05 or 6.05 c/d, and we
cannot tell the difference even with the many 6-hour runs we're getting.
Lasse Jensen has started observing it from Denmark, but is plagued by the
lack of comparisons, the lack of aperture, the southerly dec, and, well,
Denmark.  So we really, really need observations from other longitudes!
(I thought I could resolve the alias from the present data, but find that
I cannot.)

I hear from Alon Retter and Dan Rolfe that some observations may occur
over the next week from Israel and the Canaries, which would help a lot.
And the Kiwis often deliver big-time (esp. Marc Bos and Stan Walker),
though I usually find out much later.  These are merely scheduled
observations, but the importance of all this is very high (apsidal
superhumps in a DQ Her star, that's a first) and continued coverage over
the next week from USA longitudes is very desirable - despite what I said
in the last message!

I think IP Peg is very peachy too. The weather has been so good in the
southwest that I'm feeling greedy.  Can we get 'em both?

             joe

Kiwis don't feel neglected - I hope that you'll be able to break this
alias!  And you *certainly* will find the antics of this star in 1999
awesome.