From jop at astro.columbia.edu Mon Jun 3 08:49:38 2013 From: jop at astro.columbia.edu (Joe Patterson) Date: Mon, 03 Jun 2013 08:49:38 -0400 Subject: (cba:news) stars for june Message-ID: <51AC90E2.7090103@astro.columbia.edu> Dear CBAers, Here's a long-overdue cba letter. Many new stars! Some people have trouble reading these things... so I think I've attached in pdf and word format. joe -------------- next part -------------- A non-text attachment was scrubbed... Name: cba52313.pdf Type: application/pdf Size: 36198 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: cba52313.docx Type: application/vnd.openxmlformats-officedocument.wordprocessingml.document Size: 6420 bytes Desc: not available URL: From jop at astro.columbia.edu Mon Jun 3 08:54:51 2013 From: jop at astro.columbia.edu (Joe Patterson) Date: Mon, 03 Jun 2013 08:54:51 -0400 Subject: (cba:news) Fwd: PNV J19150199+0719471, a UGWZ(?) in outburst at V=10.6 In-Reply-To: <1370067658.9769.YahooMailClassic@web171405.mail.ir2.yahoo.com> References: <1370067658.9769.YahooMailClassic@web171405.mail.ir2.yahoo.com> Message-ID: <51AC921B.6090602@astro.columbia.edu> And here's a re-send of Patrick Schmeer's message giving details on this important star. Almost certainly it will become one of the most important dwarf novae in the sky. Its high proper motion and high brightness indicate that it is one of the nearest CVs, yet it resisted discovery until now. Food for thought. joe PNV J19150199+0719471 Newly discovered probable WZ Sge-type dwarf nova in Aquila, currently at magnitude V=10.6 (discoverer: Koichi Itagaki (Yamagata, Japan)). http://www.cbat.eps.harvard.edu/unconf/followups/J06270375+3952504.html Astrometry and photometry by Enrique de Miguel: R.A. 19:15:02.047 decl. +07:19:46.78 (J 2000.0) 2013 June 1.01 UT, V = 10.56, B = 10.40 (private message). The blue colour and the large proper motion indicate that PNV J19150199+0719471 (= IPHAS J191502.09+071947.6?) is probably a dwarf nova in outburst (Taichi Kato, vsnet-alert 15768). According to the PPMXL catalog this object has a large proper motion: pmRA = -97.4 mas/yr and pmDE = -93.8 mas/yr. PNV J19150199+0719471 is probably not a nova but a nearby WZ Sge-type dwarf nova in outburst. Spectroscopy and time-resolved photometry are strongly recommended. Clear skies, Patrick ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Fri Jun 7 19:59:31 2013 From: jop at astro.columbia.edu (Joe Patterson) Date: Fri, 07 Jun 2013 19:59:31 -0400 Subject: (cba:news) GW Lib! Message-ID: <51B273E3.6040401@astro.columbia.edu> Dear CBAers, Let's see of we can get an intensive GW Lib campaign over the next week. The recent HST observation showed a strangely high temperature, and some high-amplitude fast oscillations. But since all HST observations are very brief windows into a star's soul, we absolutely rely on earthbound telescopes to tell us what the overall story is. In particular, does the star still exhibit the 20 minute and 4.2 hour variations it did shortly after its dwarf-nova outburst? If so, we can use the amplitudes at 6000 A (from our data) and 1500 A (from the HST data) to obtain an excellent constraint on the source temperature... which is sometimes exactly what's needed to determine the origin(s). It's well-placed now for southern observers, but 4 min worth with each passing day. So far we just have a couple nights fro Bob Rea this season - it would be great to make a strong push NOW on this star! Just for the record, thanks for all the effort on PNV1915+07. We're analyzing every night's data just as it comes in... and still waiting for the BIG superhumps which are likely to pop into view in the next few days. joe From jop at astro.columbia.edu Tue Jun 11 19:06:01 2013 From: jop at astro.columbia.edu (Joe Patterson) Date: Tue, 11 Jun 2013 19:06:01 -0400 Subject: (cba:news) PNV J19150199+0719471 Message-ID: <51B7AD59.2030101@astro.columbia.edu> Dear CBAers, This great new dwarf nova is now 12th mag and superhumping at large amplitude. But our coverage has been a little sparse - not quite up to our usual standards (in quantity - the quality has been excellent). Let's give this star a very high priority! joe