From jop at astro.columbia.edu Mon Oct 10 17:44:16 2016 From: jop at astro.columbia.edu (Joe Patterson) Date: Mon, 10 Oct 2016 17:44:16 -0400 Subject: (cba:news) stars for october Message-ID: <74841179-92ad-b0b1-8e09-a4781478bbeb@astro.columbia.edu> Hi CBAers, Here's a good menu for October nights. Plain-text file. I might have forgotten an important star, so feel free to ask! Also, I hope to see some of you in Boston next month (AAVSO). joe p -------------- next part -------------- October 10, 2016. Dear CBAers, New month, new stars. As some of you know, Enrique spent the summer in New York, and we scrambled to get some of our projects concluded while we had that opportunity. We had a few single-star successes (ES Cet, RX2133+51, IM Nor; and CD Ind from Gordon Myers)... but the most amazing accomplishment, to me, was his successful phase-up of the "spin pulses" of 8-10 DQ Her stars. The period changes in these stars have always been puzzling. Some are spinning up, some are spinning down, some are doing both (not simultaneously!). I've always been pessimistic that I would ever solve this problem, but kept the campaigns going year after year, since we're the only people able and willing to do it. I thought we were basically stockpiling data for someone *else* to figure it out many years from now. But Enrique solved it this summer. He found, basically, that you can measure accretion rate by measuring the spin-up rates. The DQs with Porb exceeding 3 hours show 10**-8 Mo/yr, and those with Porb<2.5 hours show 10**-10 Mo/yr. So far, no exceptions! Of course we'll keep these campaigns going. Once you have established the cycle count over many years, the amount of coverage needed to extend it is pretty small. And so, STARS FOR OCTOBER: V704 And. We need a few weeks of very extensive coverage. Long as possible, as frequent as possible for a few weeks. RX And. Many-telescope campaign going on now from space. Let's support it as best we can. V592 Cas. Bright, perfectly placed in the northern sky, and a star that has so far concealed its secrets from us. FS Aur: same story. ES Cet. The star is faint and with a very fast period (10 minutes). But let's get a few more timings on it before completing our study. Each of these stars calls for a "campaign" - an intensive series of nightly observations. Others are somewhat more speculative; we need to look at a few runs and see how promising is the star. Some are pretty faint, too; I *think* we can get good data on them, but it remains to be proven. T Pyx (just coming out in the morning sky, I hope). If you can get 2 hour runs, that would be good. Longer is better, of course. HZ Pup, also just coming out in the morning, maybe. If not now, then as soon as you can manage 2 hour runs on it. HV Cet. 19th mag, a stretch - but "high priority" if you can manage it. V1500 Cyg and V Per. 18th mag, but ex-novae, which have become our favorite kinds of targets. Can you get 'em? That's it. Enrique, can you advise on PX And? The coverage looks amazingly good, but I haven't analyzed the actual data. joe p -------------- next part -------------- ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Tue Oct 11 12:39:43 2016 From: jop at astro.columbia.edu (Joe Patterson) Date: Tue, 11 Oct 2016 12:39:43 -0400 Subject: (cba:news) RX And - urgent, urgent In-Reply-To: <1ACF80922713204BA703D6242931D1632C3AA727@SRV00048.soton.ac.uk> References: <1ACF80922713204BA703D6242931D1632C3AA727@SRV00048.soton.ac.uk> Message-ID: <80759943-e40c-bafb-ad94-6b4eb62cc4ee@astro.columbia.edu> write christian if you see it risen! joe -------- Forwarded Message -------- Subject: Urgent: RX And Date: Tue, 11 Oct 2016 16:27:10 +0000 From: Knigge C. To: Joe Patterson Hi Joe, I am thinking about triggering our first Chandra ToO on RX And during the next outburst -- the previous one was a wide one, and the plan is to go for the first narrow one after a wide one. Based on the latest AAVSO light curve, I think we *may* just have seen the very start of the rise, but I can't be sure yet. Is there any chance you could get an urgent message out to the CBAers (especially the non-US-based ones) to monitor RX And closely and send an email to me as soon as they feel sure that the next eruption has begun? Close monitoring after this time would also be important. Thanks! Christian -- =================================================== Professor Christian Knigge Physics & Astronomy University of Southampton Southampton SO17 1BJ ==================================================== ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Wed Oct 12 02:57:58 2016 From: jop at astro.columbia.edu (Joe Patterson) Date: Wed, 12 Oct 2016 02:57:58 -0400 Subject: (cba:news) Fwd: RX And -- triggered In-Reply-To: <1ACF80922713204BA703D6242931D1632C3AB4F3@SRV00048.soton.ac.uk> References: <1ACF80922713204BA703D6242931D1632C3AB4F3@SRV00048.soton.ac.uk> Message-ID: <5aa13856-abfb-ef37-3fed-8db8e709e23c@astro.columbia.edu> So this means that RX And is now the number-one priority! joe p -------- Forwarded Message -------- Subject: RX And -- triggered Date: Tue, 11 Oct 2016 23:37:46 +0000 From: Knigge C. To: Elizabeth Waagen , Stella Kafka , Altamirano D. , Gandhi P. , Greg Sivakoff , James Miller-Jones , Elmar Koerding , Joe Patterson , baavss-alert at yahoogroups.com I have formally triggered the Chandra ToO on RX And (see below). Officially our window is 5-7 days from trigger, but I've cheekily asked for 5 days or even sooner if possible. We'll see if they complain. 7 days *might* be OK, but could already find the system on the way back down. I'll obviously keep everybody posted on actual scheduling windows, once I have them.. Elmar/James/Greg: time to get the radio trigger sorted, if at all possible.. Diego: ditto for Swift -- let's talk tomorrow about optimal UVOT filters It would also be fantastic to get really dense and continuous optical coverage of this entire outburst! THanks all, and fingers crossed! Cheers, Christian -------- Forwarded Message -------- Subject: Chandra RPS Proposal Receipt Date: 12/10/16 00:29 From: cxchelp at head.cfa.harvard.edu To: Knigge C. The Peer-reviewed TOO Trigger request described below has been received by the Chandra X-ray Observatory. Submission Date = Tue Oct 11 19:28:29 EDT 2016 Obs ID = 19016 Seq Num = 300398 Proposal = 18300689 Proposal Title = EUV Emission from Accreting White Dwarfs in Outburst: A Pathfinder for the Great Observatories Accretion Legacy Survey P.I. = Knigge P.I. Email = C.Knigge at soton.ac.uk 24 Hr. Contact Information = c.knigge at soton.ac.uk +44-7922-067242 Trigger Criteria = Triggers for both targets will be provided by the AAVSO, on confirmation of a rise to outburst (based on a ~1.0 mag increase in optical brightness). Trigger Justification = ~1 mag brightening of the source confirmed by AAVSO / CBA / BAAVSS Response Window = 5-15 (days) CXC Start = 5.0 (days) CXC Stop = 7.0 (days) Changes in Response Window = 5.0 -- the outburst is expected to last *at most* 7 days, and possibly only 5. If response within 5.0 days of trigger is not possible, please contact the PI, as it may in that case be better to try again later. Earlier observations (any time between 1.0 - 5.0 days from trigger) would be fine, and indeed earlier in that window is preferred. Target Name = RX AND Position (Equatorial J2000) RA = 01 04 35.50 16.147917 Dec = +41 17 57.80 41.299389 Instrument = HRC-S Grating = LETG SI Mode = DEFAULT Rem Time = 25.0 Observation Change Requests = No change. -- =================================================== Professor Christian Knigge Physics & Astronomy University of Southampton Southampton SO17 1BJ ==================================================== ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Fri Oct 14 14:44:58 2016 From: jop at astro.columbia.edu (Joe Patterson) Date: Fri, 14 Oct 2016 14:44:58 -0400 Subject: (cba:news) Fwd: RX And -- Chandra Scheduled For Oct-15-2016--7:27PM In-Reply-To: <1ACF80922713204BA703D6242931D1632C3B11CC@SRV00048.soton.ac.uk> References: <1ACF80922713204BA703D6242931D1632C3B11CC@SRV00048.soton.ac.uk> Message-ID: The X-ray observation of RX And is scheduled for tonight/tomorrow - so let's get the densest possible coverage the next few nights, starting now! joe -------- Forwarded Message -------- Subject: RX And -- Chandra Scheduled For Oct-15-2016--7:27PM Date: Fri, 14 Oct 2016 15:24:45 +0000 From: Knigge C. To: Altamirano D. , Gandhi P. , Fraser Lewis , Joe Patterson , baavss-alert at yahoogroups.com , eowaagen at aavso.org , Stella Kafka , Elmar Koerding , Greg Sivakoff , James Miller-Jones , Kim Page , Paul Kuin More details here: http://cda.cfa.harvard.edu/chaser/startViewer.do?menuItem=sequenceSummary&obsid=19016 Any observations between now and the end of the outburst -- and, of course, especially overlapping with the actual data -- will be extremely useful. Given the timing, it seems like Europe will be well placed... Cheers, Christian -- =================================================== Professor Christian Knigge Physics & Astronomy University of Southampton Southampton SO17 1BJ ==================================================== ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/