(cba:news) successes and entreaties

Joe Patterson jop at astro.columbia.edu
Thu Nov 21 13:39:56 EST 2002

Dear CBAers,

Just one more class until a school break, when I can get back to some good
variable star work.  In the meantime...

The campaign on EC0528-5857 has been entirely successful.  We have
round-the-world fully calibrated coverage, and 45 days worth - it don't
get no better than that!  The main signals present are at 6.701(4) and
6.126(6) c/d.  The high stability of the former strongly favors its
identification as nu-orb - implying an apsidal superhump with a period
excess of 9.4%.  Quite an excellent match to AO Psc in that regard - yet
no evidence for magnetism as is so obvious in AO Psc (from coherent 14
minute pulses).  It's surprising to see that a disk phenomenon like
superhumps should be so indifferent as to whether a strong magnetic field
is present!

I think that result ain't gonna get no better - let's give EC0528 a golden
handshake and move on.

The first ten days of the Tau2 campaign have been really fascinating.
This is definitely a multiperiodic star.  The signals are strong and rich
in harmonic content.  So far all of the coverage is from North America,
so there are still some aliasing issues (even with 7 hour runs).  We
urgently need some European/African/Oceanic artillery trained on this
star!  At 0400+06, it's well positioned for everyone, crossing the
meridian at local midnight the world over.  I'll send a recommended comp
star in the next message.  But as usual the comp star recommendation is
weak; you can choose one convenient for you, and the chef can probably
calibrate it out in the CBA kitchen (using time overlaps).

I think the Moon has just now cleared out of the way, so I'm really
psyched for 3 solid weeks of coverage.

>From time to time I mention FY Per and FS Aur.  These are strange stars
which flash photometric periods evidently unrelated to their orbital
periods (though slow - 1.5 and 3.4 hrs).  They're reasonably bright and
northern - excellent targets for northern small scopes.

In the south, on a really still night, you can hear a novalike variable
crying out for coverage.  This is EC04224-2014, probably a UX UMa star
with a period near 4 hrs.  It's about 12th magnitude, which is probably
why you can hear it.  The star is called simply "Eri" (along with others
of that name) in the Living CV Catalogue.  Coords 04 24 41.06 -20 07 11.5.

So that's the Thanksgiving menu.  Let's hope it includes no turkeys.


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