From jop at astro.columbia.edu Fri Nov 10 15:14:51 2000 From: jop at astro.columbia.edu (Joe Patterson) Date: Fri, 10 Nov 2000 15:14:51 -0500 (EST) Subject: (cba:news) New targets for November Message-ID: Dear CBAers, Let's bring our campaign on GD 552 = Cep 1 to an end. We received great coverage from John Stull and Dave Toot on the Alfred 32", and Dave East and Cap'n Bob did their usual thing. So we have a 60-day campaign, very well sampled. The preliminary results are somewhat disappointing: no obvious superhumps, no stable precession, just an occasional flare and flickering of course. We did manage to get a refined orbital period of 0.07127+-0.00005 d. Time to show this star off the stage for 2000. Most of our southerners are working on VY Scl. This is another complicated star, with signals that are periodic but not particularly stable. I think we probably have enough to end the year's coverage. Fred and Jennie have sent in some data on BW Scl (=RX2353-38), and it would be great to have more. I realize this star is a bit faint and the season is maybe a bit late - but see what you can do. Otherwise, the two good stars for southern coverage are TW Pic and RR Pic. Enjoy those negative decs! In the north, I recommend PX And and BZ Cam. The first few light curves of BZ Cam have arrived, and show no obvious periodic signals, but a few nights of long coverage should really nail this down. PX And is an eclipsing star which has shown superhumps in the past, and might even have them all the time; anyway, the simultaneous presence of eclipses and superhumps should allow us to map the physical origin of the superhump light in the binary. So: north : PX And, BZ Cam south: BW Scl, TW Pic, RR Pic joe From jop at astro.columbia.edu Fri Nov 10 15:23:58 2000 From: jop at astro.columbia.edu (Joe Patterson) Date: Fri, 10 Nov 2000 15:23:58 -0500 (EST) Subject: (cba:news) IX Dra Message-ID: Oops, I forgot to mention IX Dra! This is Tonny's new superhump star, which erupted about a week ago (or more?). I was travelling and couldn't react, but if it is still up it is definitely a good choice for timing the humps and thereby getting a more accurate superhump period. So toss that into the mix too! (Tonny, could you advise us about its brightness now?) joe From jop at astro.columbia.edu Sun Nov 12 09:22:13 2000 From: jop at astro.columbia.edu (Joe Patterson) Date: Sun, 12 Nov 2000 09:22:13 -0500 (EST) Subject: (cba:news) IX Dra Message-ID: Dear CBAers, Brian Martin just sent some data on IX Dra, and though around 15-16 it appears to be still superhumping. It's late in the outburst, so I imagine it will give up the ghost in a few days. Try to observe this star on a top-priority basis while it remains visible. With me travelling and the unfavorable RA, I'm afraid this one may have slipped through - unless someone manages to move fast. It will probably take European + NA coverage to get the aliases tamed. Tonny and Brian have observed it, but we need some coverage within the same 24-hr interval. Borealites, shirk it not. joe From jop at astro.columbia.edu Thu Nov 16 15:09:27 2000 From: jop at astro.columbia.edu (Joe Patterson) Date: Thu, 16 Nov 2000 15:09:27 -0500 (EST) Subject: (cba:news) outburst of YY Dra = DO Dra Message-ID: Dear CBAers, Patrick Schmeer and Chris Jones have caught good ol' YY Dra going into eruption last night. At mag 10.6-11, it should be plenty bright, and it should be a prime target of borealite CBAers. Sorry about the lousy timing for a star at 11h 50m, but the dec of +72 degrees should be reassuring. We're interested in variations near the 4 hr orbital period, but also the 8.8 minute spin period (of the magnetic white dwarf). Since the star often has power at the first harmonic (i.e. 4.4 minutes), make sure your observations are pretty rapid (every 1 minute would be OK, every 40 s would be better). Several past outbursts have been quite short, not lasting long enough for us to get any appreciable amount of data. Let's see what we can do this time! By the way, the PX And data is just now starting to come in. A very nice evening target! joe ---------- Forwarded message ---------- Date: Thu, 16 Nov 2000 20:01:59 +0100 From: Patrick Schmeer To: vsnet-obs at kusastro.kyoto-u.ac.jp Subject: (cba:news) [vsnet-obs 30734] DO Dra outburst DRADO 20001115.72 <125 Scp DRADO 20001115.90 <133 Scp DRADO 20001116.729 111 Scp DRADO 20001116.776 110 Scp From jk at cbastro.org Sun Nov 19 12:40:25 2000 From: jk at cbastro.org (Jonathan Kemp) Date: Sun, 19 Nov 2000 07:40:25 -1000 (HST) Subject: (cba:news) one-year anniversary of the data archive Message-ID: Hi CBAers, Well, today marks the one-year anniversary of the CBA data archive! To date, we have gotten more than 1200 data submissions from amateurs and professionals in support of CBA and CV science. Kudos to all who have been contributing. Following is a listing of data contributions received in the first year of operation of the CBA data archive. With luck, there will be many more successful years for the data archive. Dave Skillman CBA East Ctr for Basement Astrophysics 180 Jonathan Kemp CBA Hilo et al MDM Obs & CTIO Obs 179 Bob Fried CBA Flagstaff Braeside Obs 156 Tonny Vanmunster CBA Belgium 145 Lew Cook CBA Concord 88 McCormick & Velthuis CBA Pakarunga Farm Cove Obs 83 Brian Martin CBA Alberta King's Univ College Obs 74 Robert Rea CBA Nelson Regent Lane Obs 69 Lasse Jensen CBA Denmark 53 Neil Butterworth CBA Townsville 48 Marc Bos CBA Otahuhu 47 Dave Harvey CBA West 32 Stan Walker CBA Waiharara Wharemaru Obs 32 Paul Warhurst CBA Auckland Univ Of Auckland Astron Obs 10 Gianluca Masi CBA Italy Bellatrix Obs 9 James Hannon CBA Connecticut 7 As a reminder, we encourage data from both amateurs and professionals to be submitted to our data archive address (data at cbastro.org) which transparently archives and passes along data to Joe and I. If you have not been sending data to this address, I heartily encourage you to do so! Of course, the above totals only include submissions directed toward the archive and also don't include the thousands of data sets contributed by the old-time CBAers before the archive's existence. Also, if you have old data sets which you have submitted, but not to the data archive but directly to one of us, I encourage resubmission to our address for older data sets (data-old at cbastro.org). I might make the suggestions that, if possible and easy for observers, data sets be submitted in separate e-mails. This makes the bookkeeping and archiving a tad easier. Including the date, in addition to the object, in the subject line is helpful, too. If you have any questions about how to submit data, please check out our web page with advice on this subject (cbastro.org/data). Lastly, CBAers should consider the archive to be at their disposal it they wish to study data sets on a given star for a project. Please send all requests to Joe and I. Aloha, Jonathan CBA Hilo Center for Beachside Astrophysics From jop at astro.columbia.edu Thu Nov 23 07:55:32 2000 From: jop at astro.columbia.edu (Joe Patterson) Date: Thu, 23 Nov 2000 07:55:32 -0500 (EST) Subject: (cba:news) adieu to yy dra Message-ID: Dear CBAers, Well that was another short outburst for YY Dra. I still dunno what people managed to get. If you got a couple of nights, you might want to get a couple more to establish baseline (comparison with outburst). If you haven't started yet, it's probably not so good a target. PX And is performing quite beautifully with negative superhumps and a 4-day signal. I strongly recommend this one as it's sloping westward away from view (but still has a few weeks of good visibility). For australites, TW Pic and RR Pic are the stars of choice now. Off for Thanksgiving vacation in a few hours. Back Monday. joe From jop at astro.columbia.edu Thu Nov 30 09:57:42 2000 From: jop at astro.columbia.edu (Joe Patterson) Date: Thu, 30 Nov 2000 09:57:42 -0500 (EST) Subject: (cba:news) The seasons, they go round and round Message-ID: Dear CBAers, Time for a fresh update on targets. The main northern target has been PX And. We've had good coverage and seen the customary negative superhump, though decidedly weaker than in 1996-1997. Time to bring this campaign to an end. The best long-night target to replace it is WX Ari, just about the only superhump holdout among the SW Sex stars. It's a great time of year for long coverage, and I hope we can get some AU/NZ coverage too - at a dec of +10 it shouldn't be too exotic for those folks. Chart on the CBA website. Two major developments down south. Fred and Jennie have been firing away at BW Scl. They haven't had the best of weather and the star's a bit faint, but their coverage is easily good enough to extend the binary ephemeris (indefinitely). So that's reward number one. But lo and behold, another signal popped up, a very big one... a signal at Porb+16%. We don't know yet what this is, but you southerners can still follow this thing - so I sure hope you do! Next year we'll mount a major campaign from several sites - but this is a *transient* phenomenon (lasts maybe a few weeks to a few months), so it won't always be there. It's very late in the observing season, but see what you can do! By the way, this signal was found earlier by Tim Abbott. You can see it in Astr and Ap, 318, 137 (Figure 8). But he thought it might be due to aliasing. It's not - it's quite far displaced from the putative Porb. Similar excellent news re RR Pic. I've spent the last few days studying these light curves. As Vogt, Warner, etc. previously found, the light curve changes shape but maintains a basic periodicity of 0.14502 days. Our data suggest that the changes are themselves cyclic with a period near 2.0 days. One of the 10-day segments shows an obvious negative superhump at omega-orb + 0.48 c/day, plus a strong signal at 0.48 c/day. Happily, RR Pic season is just getting started, so I warmly recommend this fine star for your summer enjoyment down there! And I'll be happy to send all the data to any fine deserving southerner. Finally, here's my usual request for DQ Her star observations: FO Aqr, AO Psc, V709 Cas, BG CMi (especially), V405 Aur. Very nice targets for quickies. Mind your clocks. 1-900-410-TIME just to be sure. joe