(cba:news) Midsummer and midwinter stars

Joe Patterson jop at astro.columbia.edu
Sat Jul 15 13:13:14 EDT 2000

Dear CBAers,

Back in NYC a few days now, what a great feeling to be home!

The campaign on V1494 Aql is going quite well, with very frequent hits by
Dave East and Cap'n Bob.  A strong signal at 14.851(12) c/day is certainly
present.  There's some structure near 0.5 and 1.5 times this frequency,
but with the present longitude distribution I'm afraid it's pretty close
to the noise.  A few runs from Fred and Jennie, and Neil Butterworth, have
helped but the signals are just too weak to be sure.  This is a 1999 
nova and is continuing to slowly fade, so the periodic content is
likely to evolve over the next few years.  The examples of Nova Cyg 75
and Nova Cyg 92 showed that on a timescale of a few months, the periodic
structure can change significantly.  So let's take it off the critical
list right now, observe it more leisurely through July and August, and
perhaps do a mini-campaign in Sep-Oct.  It remains a good target
throughout, though, especially if you want something bright.

The Hamburger star, 1450+63 or thereabouts, was written up and submitted
by Tonny to IBVS a few days ago.  Good job.

An interesting dwarf nova, DM Lyrae, just went into superoutburst.  This
is a very good one to do, definitely worth banging the CBA alert drums
for.  We have a Porb, so knowledge of P(superhump) will give us the
precious epsilon! [=(Psh-Porb)/Porb]

And V751 Cyg is back in the sky bigtime - let's jump on that one with full
CBA fury, and couple with last year's campaign to give us a one-year
baseline for period solution.  Pronto.  Bob, this would be a good one to
do multicolor, but 3 or even 2 passbands would be fine.

Then there are the DQ Hers: always lovely, always underappreciated!
DQ Her, FO Aqr, AO Psc, V1223 Sgr, V709 Cas.


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