From jop at astro.columbia.edu Sat Dec 5 09:18:16 2015 From: jop at astro.columbia.edu (Joe Patterson) Date: Sat, 5 Dec 2015 09:18:16 -0500 Subject: (cba:news) december stars - plenty Message-ID: <5662F228.5070600@astro.columbia.edu> Dear CBAers, The seasons, they go round and round... and we're captive on the carousel of time. The first hard frost therefore means: time for a CBA-target change. The glamor targets of the week are: 1. PM0333+3320 (the Thorstensen-Skinner-Lepine proper motion star). Possibly an "ordinary" dwarf nova now in superoutbrst... but perhaps very special because of the very high proper motion. Such stars are probably quite nearby, and deserve very close attention. Also the humps are now enormous. Great northern target, now at mag 13.7, and at 03 33 54.5 +33 20 05. 2. NSV 1440 = ASASSN-15sz. Seemingly a far-south (Mensa) counterpart of CR Boo, with a very short Porb and now engaged in a series of echo outbursts (coming down from a supermax at 12.5). The light curve yoyos a lot, but the periodic signal remains. We need a few more weeks of coverage, if the star cooperates. But for this and future weeks, here's an appealing menu of new stars. 3. HZ Puppis (8 03 22.8 -28 28 28.8) = Nova Pup 1963. An obvious DQ Her system; we need another season to put it to rest. We need some early-season (now) and late-season (April) runs to establish precise cycle count... and a big push in Jan-Feb to parse the somewhat intricate period structure (sidebands, etc.) 4. Swift J0614+17 (=2MASS 06141230+1704321) (6 14 12.28 +17 04 32.6). Another new DQ Her, which is discussed in astro-ph 1510.00703 (Halpern & Thorstensen). V=17.5, but it's a healthy 23-minute signal. We've been sporadically tracking it, but now it's time to pick up the pace and establish a precise ephemeris. 5. Swift J0503-28 (5 03 49.25 -28 23 8.8) V=18.1, so this is ambitious. Another DQ with P = 16 min. 6. Swift J0525.6+2416 (5 25 22.75 +24 13 33.5) V=16.6 and P = 4 min. Anoter DQ Her star, keep the exposure short to resolve the pulse. BTW stars 4, 5, and 6 are ALL in the Halpern-Thorstensen paper described above: http://arxiv.org/abs/1510.00703 7. V902 Mon (6 27 46.4 +1 48 11). Eclipsing star, nature still unknown but likely to be a DQ Her or V Sge star. Doesn't nicely fit into any known category, though. 8. V959 Mon = Nova Mon 2012 (6 39 38.74 +5 53 52.0). Let's get another "seasonal" orbital light curve of this interesting gamma-ray nova. 7 hours, so only long runs need apply. 9. T Pyx. You bet! It's time again. The orbital period lurched upward suddenly during the outburst, and now appears to be resuming its "quiescent" positive Pdot - at least the last we checked. We need another season - actually, just another month would suffice, to verify that the 2013-2014 behavior continues. As for CURRENT (or recent) stars on the menu, I recommend dropping IM Eri and AH Men, and demoting AQ Men at least until NSV 1440 vanishes. FS Aur is still good for an occasional run, but doesn't need anything steady. Enrique will advise on 0644+33. As usual, long runs on one target tends to be the most effective strategy. But don't let the shiny new targets crowd out T Pyx! joe ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Sun Dec 6 21:33:38 2015 From: jop at astro.columbia.edu (Joe Patterson) Date: Sun, 6 Dec 2015 21:33:38 -0500 Subject: (cba:news) december stars, redux In-Reply-To: <5662F228.5070600@astro.columbia.edu> References: <5662F228.5070600@astro.columbia.edu> Message-ID: <5664F002.5060404@astro.columbia.edu> To supplement this note: 1. TV Col is done for the year. 2. For RX0644+33 we have a lot of data, and superhumps are absent. However, the star has now faded by nearly a magnitude, and the orbital waveform has changed substantially (considerably larger amplitude, in magnitude units). That's quite interesting, and worth tracking further - *if* you have been observing it (I have the various observers cross calibrated). Otherwise, move to other stars. 3. HS0455+83 has *possible* superhumps. A few more nights will say yea or nay. 4. I think FS Aur can demoted to once-every-3-weeks status. More on other stars in a day or two. Joe P -------- Forwarded Message -------- Return-Path: Dear CBAers, The seasons, they go round and round... and we're captive on the carousel of time. The first hard frost therefore means: time for a CBA-target change. The glamor targets of the week are: 1. PM0333+3320 (the Thorstensen-Skinner-Lepine proper motion star). Possibly an "ordinary" dwarf nova now in superoutbrst... but perhaps very special because of the very high proper motion. Such stars are probably quite nearby, and deserve very close attention. Also the humps are now enormous. Great northern target, now at mag 13.7, and at 03 33 54.5 +33 20 05. 2. NSV 1440 = ASASSN-15sz. Seemingly a far-south (Mensa) counterpart of CR Boo, with a very short Porb and now engaged in a series of echo outbursts (coming down from a supermax at 12.5). The light curve yoyos a lot, but the periodic signal remains. We need a few more weeks of coverage, if the star cooperates. But for this and future weeks, here's an appealing menu of new stars. 3. HZ Puppis (8 03 22.8 -28 28 28.8) = Nova Pup 1963. An obvious DQ Her system; we need another season to put it to rest. We need some early-season (now) and late-season (April) runs to establish precise cycle count... and a big push in Jan-Feb to parse the somewhat intricate period structure (sidebands, etc.) 4. Swift J0614+17 (=2MASS 06141230+1704321) (6 14 12.28 +17 04 32.6). Another new DQ Her, which is discussed in astro-ph 1510.00703 (Halpern & Thorstensen). V=17.5, but it's a healthy 23-minute signal. We've been sporadically tracking it, but now it's time to pick up the pace and establish a precise ephemeris. 5. Swift J0503-28 (5 03 49.25 -28 23 8.8) V=18.1, so this is ambitious. Another DQ with P = 16 min. 6. Swift J0525.6+2416 (5 25 22.75 +24 13 33.5) V=16.6 and P = 4 min. Anoter DQ Her star, keep the exposure short to resolve the pulse. BTW stars 4, 5, and 6 are ALL in the Halpern-Thorstensen paper described above: http://arxiv.org/abs/1510.00703 7. V902 Mon (6 27 46.4 +1 48 11). Eclipsing star, nature still unknown but likely to be a DQ Her or V Sge star. Doesn't nicely fit into any known category, though. 8. V959 Mon = Nova Mon 2012 (6 39 38.74 +5 53 52.0). Let's get another "seasonal" orbital light curve of this interesting gamma-ray nova. 7 hours, so only long runs need apply. 9. T Pyx. You bet! It's time again. The orbital period lurched upward suddenly during the outburst, and now appears to be resuming its "quiescent" positive Pdot - at least the last we checked. We need another season - actually, just another month would suffice, to verify that the 2013-2014 behavior continues. As for CURRENT (or recent) stars on the menu, I recommend dropping IM Eri and AH Men, and demoting AQ Men at least until NSV 1440 vanishes. FS Aur is still good for an occasional run, but doesn't need anything steady. Enrique will advise on 0644+33. As usual, long runs on one target tends to be the most effective strategy. But don't let the shiny new targets crowd out T Pyx! joe ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/