From jop at astro.columbia.edu  Thu Jan  4 08:12:48 2007
From: jop at astro.columbia.edu (Joe Patterson)
Date: Thu, 4 Jan 2007 08:12:48 -0500 (EST)
Subject: (cba:news) V1212 Tau erupting
Message-ID: <Pine.LNX.4.64.0701040805030.4741@pluto.astro.columbia.edu>


Dear CBAers,

Yesterday a CV suspect, V1212 Tau, was found in outburst.  A first night 
on it at Kitt Peak yielded strong superhumps with P=0.075 d.  Since this 
is the first recorded supermax, this star is worth a concerted campaign.
It's about 16th mag, so better act fast!

More detailed message later today. The onrushing Moon is difficult to 
survive on these northern nights.  Maybe the south will be better.  It's T 
Pyx season again, and it's a pretty good target at V=15.  Plus AH Pic, for 
which we need another 1-2 weeks of data.

In a few days, FS Aur will be clear of the Moon, and will be a very good 
target since we have a paper ready to just plug in the 2006-7 data.

More later!

joe


---------- Forwarded message ----------
Date: Thu,  4 Jan 2007 11:03:25 +0900 (JST)
From: Taichi Kato <tkato at kusastro.kyoto-u.ac.jp>
To: variable_star_forum at yahoogroups.com,
     vsnet-alert at ooruri.kusastro.kyoto-u.ac.jp, vsnet-alert at yahoogroups.com,
     vsnet-campaign-dn at ooruri.kusastro.kyoto-u.ac.jp,
     vsnet-campaign at ooruri.kusastro.kyoto-u.ac.jp,
     vsnet-outburst at ooruri.kusastro.kyoto-u.ac.jp, vsnet-outburst at yahoogroups.com
Subject: [vsnet-campaign-dn 4877] Re: V1212 Tau outburst: observation urgently
     needed

>   Carlo Gualdoni reports that V1212 Tau (see below) is undergoing
> an outburst!

    According to the GCVS team, the position is reported to be:
V1212 Tau |034856.5+251632. |035157.0+252529. |UGSU:     | 15.3    |< 21.5      |B |

http://archive.stsci.edu/prepds/cvcat/query_processor.cgi?setup_file=varcat.setup.cgi&query_decision=single_record&uid=7826&query_select=everything

RA: 	 03:51:56.97
DEC: 	+25:25:27.8

object is blue on POSS II plates




From jop at astro.columbia.edu  Wed Jan 10 14:35:00 2007
From: jop at astro.columbia.edu (Joe Patterson)
Date: Wed, 10 Jan 2007 14:35:00 -0500
Subject: (cba:news) stars for Jan 2007
Message-ID: <E1H4jDw-0006sv-3R@pluto.astro.columbia.edu>



Dear CBAers,

Time for a changing of the (CV) guard.

Four stars are done for the year.
(1) V1212 Tau - we have enough now to define Psh (Jerry Foote, Tut Campbell).
    Now we'll retire and wait for big glass to define Porb at quiescence.
(2) Var Cam 06 (OT0557+68).  Same story.  Very extensive coverage by Bob
    Koff, Dave Messier, Jerry, and the Europeans (David Boyd, Tonny, Arto,
    and Pierre de Ponthiere). Nice Psh of 0.05348 d.
(3) V1193 Ori.  Not much coverage this year... but no periodic signals.
    Last year there were several very powerful signals... so let's not
    invest more in the star now.
(4) AH Pic.  Very fine coverage by Greg, Berto, Jennie, Bob Rea, Bill Allen.
    And the result is an obvious signal at 0.14095(5) d.  That's good
    enough - let's declare victory and withdraw!

Eri = SDSS0407-06.  Whew!  What an interesting star.  We've accumulated a
lot of coverage, but the star ramps up and down quite rapidly with a 2 mag
amplitude... plus there are deep eclipses, plus the period is long, plus
it's often very faint.  Plus the season isn't quite right.  So I officially
declare this one dead for the year, with a heavy heart.

January-March is the glorious season for DQ Her stars, and most of 'em are
pretty bright, so you can track the pulses pretty well.  Here's a few very
worth doing right now, partly to track the pulse period changes:

BG CMi 0729+10
WX Pyx 0833-22 (17 but very sparsely observed)
DW Cnc 0758+16
HT Cam 0757+63 (18)
Swift 0732-13 = "Pup" (no chart, but we'll fetch one)

And here are other stars for which we need LONG coverage:
FS Aur (0547+28) - presently V=16 
T Pyx (0902-30)  - V=15.1
RR Pic (0635-62) - V=12, good for bad conditions

And here are new DQ Hers which we have just started campaigns:
Lyn = SDSS0804+51
Gem = RX0704+26

There's the menu.  Pick a star or two and keep the faith on 'em - almost
always the best procedure on these guys!

joe


From jop at astro.columbia.edu  Mon Jan 15 19:28:06 2007
From: jop at astro.columbia.edu (Joe Patterson)
Date: Mon, 15 Jan 2007 19:28:06 -0500
Subject: (cba:news) U Gem in outburst
Message-ID: <45AC1C16.3050309@astro.columbia.edu>


Dear CBAers,

U Gem is reported to be in outburst tonight (10.7).  For many years I've 
wanted to get long CBA light curves of the star through an eruption 
cycle.  This is a great chance to start, since the star is well-placed 
now and will remain so for the next 100 days!

The main purpose is to study the shape, size, and exact location 
(timing) of the bright spot eclipse.  As a secondary goal, it will test 
for the presence of superhumps (the literature is conflicting on this 
one) and for the presence/return of the orbital hump.

U Gem is a beautiful test object for the theory of bright spots, because 
the eclipse is so precisely oriented - the spot is eclipsed but not the 
white dwarf.  Fire away!

10.7 is a bit measly for a U Gem eruption, but it may brighten... and 
anyway, 3.5 mag of dynamic range is plenty enough lever arm to obtain 
some really nice scientific results.

As you settle down to observe it, investigate the local comp stars and 
recommend one that most CBAers can use.  I've not observed U Gem in 22 
years, and my notes are long gone...

joe


From jop at astro.columbia.edu  Tue Jan 16 11:32:55 2007
From: jop at astro.columbia.edu (Joe Patterson)
Date: Tue, 16 Jan 2007 11:32:55 -0500
Subject: (cba:news) U Gem in outburst
In-Reply-To: <012a01c73923$4810af00$0200a8c0@p4>
References: <012a01c73923$4810af00$0200a8c0@p4>
Message-ID: <45ACFE37.4000803@astro.columbia.edu>


Oooo... Jerry's data show that U Gem is still rising, and in fact very 
fast.  So it may get a lot brighter in the next 1-2 days.  And here it 
is transiting meridians at local midnight, with long winter nights 
available.  This is a really splendid opportunity to launch that U Gem 
campaign we've been waiting for!

Watch for saturation though.  If you observe without filters, you might 
have to go to uncomfortably short integration times.  And if you do, 
spend some time studying the performance of your camera shutter - in 
particular, how repeatable are the integration times when delta-t is 
very short?

I recommend V filter, if you got 'em.

U Gem in outburst shows very weak eclipses, sometimes almost invisible.
Historically, this is what tipped the world off that DN eruptions reside 
in the disk proper, not in a gulp of mass transfer at the disk 
periphery.  But it has never been really well constrained by a study 
through the eruption cycle - just a few odd papers here and there which 
reach somewhat weak/conflicting conclusions based on sparse data.  It's 
up to us to do a really good job now!

I think this one might be good for the Australians too, BTW.  We have a 
giant hole in our northern coverage from California (or Hawaii when Lew 
is there) westward to Norway/Belgium, and it would be mighty nice to 
plug it.  Not so unreasonable at that dec!

joe


From jop at astro.columbia.edu  Sat Jan 27 15:07:16 2007
From: jop at astro.columbia.edu (Joe Patterson)
Date: Sat, 27 Jan 2007 15:07:16 -0500
Subject: (cba:news) DW Cnc erupts
Message-ID: <45BBB0F4.5010603@astro.columbia.edu>


DEar CBAers,

As some of you know, DW Cnc erupted two nights - the first eruption seen 
in this star.  It appears to be quite a fast eruption - but it's still 
moderately bright around 13.5, and would be a superb northern target!

joe