(cba:news) another helium friend?

Joe Patterson jop at astro.columbia.edu
Wed Aug 5 07:06:02 EDT 1998


Dear CBAers,

Well, it looks like Mike Schwartz may have serendipitously found another
helium dwarf nova, and it may even still be bright (superoutburst?).  If so,
we should pounce on it forthwith!  I'm inclined to give this object the
highest priority right now, though I still think V1504 Cyg is eminently
worthy.  I attach the present info on the new star.  Think about how to
deal with that annoying galaxy.

For at least a week we should forget V1315 Aql.  We've had very good
coverage from Daves East and West, and Gianluca Masi.  The waves are
pretty well defined, and not likely to improve much with further data.
RX1940-10 is another story.  That one's worth relentless coverage for
the next 8 weeks (except when it's clobbered by moonlight, like right now).

Please send me anything you have on V1504 Cyg and the new helium star,
I promise to study it right away!

By the way, isn't anyone around in the morning sky?  V592 Cas and TT Ari
are back and awfully bright - we very much want early-season coverage so we
can tie together the cycle count for 1997 and 1998.

joe

BELGIAN ASTRONOMICAL SOCIETY V.V.S. -  Working Group Variable Stars
Cataclysmic Variables Circular No.167               1998, August 04
Ed.: T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM
     Internet: Tonny.Vanmunster at advalvas.be       TEL. 32-11-831504
     CVC Web Page : http://www.cbastro.org/cvc
===================================================================

New cataclysmic variable in Draco
=================================

We have been informed by Michael Schwartz, Cottage Grove, OR about
his discovery of a new cataclysmic variable in Draco : "I am 
'responsible' for finding supernova 1998di in an anonymous galaxy
(see IAUC 6982, that was issued on August 3rd). However, spectral 
observations now reveal that this is not a supernova, but a galactic
dwarf nova in outburst, projected near a distant anonymous galaxy".

Michael Schwartz kindly has sent us full details about the related
spectrographic analysis by Jha, Garnavich, Challis and Kirshner 
(Center for Astrophysics), that likely will appear in an IAUC 
tomorrow. The spectrum of the new dwarf nova resembles that of the
helium dwarf nova CR Boo near maximum (Patterson et al., 1997, PASP, 
109, 1100).  

The new object is located at RA = 19h24m38s.19, Decl = +59o41'46".7 
(equinox 2000.0), which is about 0".6 east and 3".8 north of the 
nucleus of an anonymous galaxy. A picture of the new object is 
available at the following URL : 
http://www2.netcom.com/~pfactors/tenagra.html

Some photometric observations :

1998 Jul 22.46 UT, [19    (M. Schwartz, unfiltered CCD image);
     Aug 02.48 UT,  16.8  (M. Schwartz, unfiltered CCD image);


We strongly recommend CCD observers to photometrically monitor this
object.


Tonny Vanmunster



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