September 2021 - vsnet-alert - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-alert 26273] ZTF21aceijig: a CV candidate with large amplitude (> ~ 6 mag)
by Kenta TAGUCHI 28 Sep '21

28 Sep '21

Dear friends, Using my private system scraping MARS ( https://mars.lco.global ), I've just found ZTF21aceijig out as a CV candidate from the public ZTF data. It's amplitude is > ~ 6.0 mag (assuming the limiting mag of PS1-g is 21.6). (I'm sorry if someone has already discovered and reported it elsewhere.) Lasair: https://lasair.roe.ac.uk/object/ZTF21aceijig ALeRCE: https://lasair.roe.ac.uk/object/ZTF21aceijig MARS: https://mars.lco.global/?objectId=ZTF21aceijig According to ALeRCE, the position is (RA, Dec) = (01:49:59.397, +54:39:27.24) Last non-detections by ZTF: g > 19.6426 on 2021-09-23.40 (ZTF, 'difference mag' via ALeRCE) r > 19.9288 on 2021-09-23.44 (ZTF, 'difference mag' via ALeRCE) Last non-detection by ASAS-SN: g > 17.124 on 2021-09-27.5628629 First detections by ZTF: g = 15.694 +/- 0.036 on 2021-09-28.33 (ZTF, 'difference mag' via ALeRCE) r = 15.865 +/- 0.032 on 2021-09-28.41 (ZTF, 'difference mag' via ALeRCE) The result of ASAS-SN Sky Patrol: https://asas-sn.osu.edu/sky-patrol/coordinate/2f155ab7-61ac-4b06-9fb7-68d40… There are no possible counterparts recorded in the PS1 mean object catalog. No known minor planets are found by the Minor Planet Checker ( https://www.minorplanetcenter.net/cgi-bin/checkmp.cgi ). Best Regards and Clear Skies, Kenta -- ________________________________________________________________ 田口健太　(TAGUCHI, Kenta) 京都大学大学院理学研究科宇宙物理学教室 (Department of Astronomy, Graduate School of Science, Kyoto University) kentagch(a)kusastro.kyoto-u.ac.jp <mailto:kentagch@kusastro.kyoto-u.ac.jp> 09090536980

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[vsnet-alert 26272] MV Lyr fading
by Taichi Kato 27 Sep '21

27 Sep '21

MV Lyr fading YYYYMMDD(UT) mag observer 20210818.8979 126 (Jose Ripero) 20210819.5537 133cG (Yutaka Maeda) 20210819.5972 129cG (Yutaka Maeda) 20210827.5989 129cG (Yutaka Maeda) 20210827.6158 132C (Masayuki Moriyama) 20210827.892 130 (Gary Poyner) 20210828.6051 132cG (Yutaka Maeda) 20210828.899 132 (Gary Poyner) 20210829.033 13.16C (Gary Poyner) 20210829.562 129 (Hiroyuki Maehara) 20210829.6161 134cG (Yutaka Maeda) 20210902.8632 133 (Eddy Muyllaert) 20210903.8903 133 (Eddy Muyllaert) 20210905.8556 134 (Eddy Muyllaert) 20210906.8625 134 (Eddy Muyllaert) 20210906.933 133 (Gary Poyner) 20210907.880 134 (Gary Poyner) 20210908.6097 132cG (Yutaka Maeda) 20210908.8438 133 (Eddy Muyllaert) 20210909.6353 13.15C (Masayuki Moriyama) 20210909.8674 133 (Eddy Muyllaert) 20210910.8396 133 (Eddy Muyllaert) 20210910.8799 132 (Jose Ripero) 20210911.8396 134 (Eddy Muyllaert) 20210915.8479 133 (Eddy Muyllaert) 20210915.869 134 (Gary Poyner) 20210918.5203 133cG (Yutaka Maeda) 20210919.5471 133cG (Yutaka Maeda) 20210919.894 133 (Gary Poyner) 20210920.8368 133 (Eddy Muyllaert) 20210921.976 134 (Gary Poyner) 20210922.4979 135cG (Yutaka Maeda) 20210922.8458 133 (Eddy Muyllaert) 20210923.4813 137:cG (Yutaka Maeda) 20210923.4966 138cG (Yutaka Maeda) 20210923.8326 133 (Eddy Muyllaert) 20210923.851 133 (Gary Poyner) 20210924.4986 135cG (Yutaka Maeda) 20210924.6506 138C (Masayuki Moriyama) 20210926.6054 13.79C (Masayuki Moriyama)

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[vsnet-alert 26271] ASASSN-21sb: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 27 Sep '21

27 Sep '21

Dear colleagues, I have just finished analysing my time-series observations of ASASSN-21sb, obtained on 2021, Sep 25/26 and Sep 26/27 at resp. CBA Extremadura Observatory and CBA Belgium observatory, using 0.40-m telescopes with SX-46 CCD and QHY-268M CMOS camera's. Regular superhumps with an amplitude of 0.32 mag are clearly visible in the resulting light curve, establishing ASASSN-21sb as a new SU UMa-type dwarf nova. A period analysis using the ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.0), yields a combined superhump period of 0.0589 +/- 0.0003d. The object was at mag CV = 16.2 on Sep 27th. I will send my observations to AAVSO, CBA and VSNET for further analysis. Best regards Tonny --- Tonny Vanmunster CBA Belgium Observatory CBA Extremadura Observatory http://www.cbabelgium.com PERANSO : The Light Curve and Period Analysis Software http://www.peranso.com

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[vsnet-alert 26270] IPHASJ190812.63+045728.1: eclipsing dwarf nova in the period gap
by Taichi Kato 27 Sep '21

27 Sep '21

IPHASJ190812.63+045728.1: eclipsing dwarf nova in the period gap From ZTF data. Porb=0.1056882(3) d. Eclipse epoch: BJD 2458662.020. The behavior up to now suggests an SS Cyg star, but a search for a superoutburst would be interesting.

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[vsnet-alert 26269] LMC V1512 (Galactic DN) outburst (Sept. 6-17)
by Patrick Schmeer 24 Sep '21

24 Sep '21

LMC V1512 = "Nova" Mensae 1951 (UG) https://www.aavso.org/vsx/index.php?view=detail.top&oid=236395 A relatively rare outburst started on 2021 September 6 according to recent ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K) data: https://asas-sn.osu.edu/sky-patrol/coordinate/1348a779-1ab5-4f79-a58c-183ed… https://asas-sn.osu.edu/sky-patrol/coordinate/3e9155c6-4573-4917-9f6c-4c0bd… An apparent (short) rebrightening during the relatively fast decline (faster than that of a standard UGSU superoutburst) occurred on September 14. A previous outburst (= ASASSN-17lo) was recorded from 2017 August 29 to September 7 by the ASAS-SN Sky Patrol. Regards, Patrick

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[vsnet-alert 26268] CRTS J145921.8+354806 superoutburst
by Taichi Kato 23 Sep '21

23 Sep '21

CRTS J145921.8+354806 superoutburst YYYYMMDD(UT) mag observer 20210921.1771 15.703zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210923.1584 15.411zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210923.1746 15.803zr (Zwicky Transient Facility Lasair (Masci+ 2019))

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[vsnet-alert 26267] ASASSN-16og outburst
by Balaji Kumar 23 Sep '21

23 Sep '21

Our transient survey has detected an outburst of ASSASN-16og. First observed date: September 21.30969 Magnitude: 14.9 R ---------------- Balaji Golden Ears Observatory Transient Survey Maple Ridge, Canada

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[vsnet-alert 26266] V544 Her faded after double outburst and apparently rebrightened
by Taichi Kato 22 Sep '21

22 Sep '21

V544 Her faded after double outburst and apparently rebrightened YYYYMMDD(UT) mag observer 20210819.5030 <156c (Yutaka Maeda) 20210820.5016 <146c (Yutaka Maeda) 20210824.1742 15.119zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210824.1938 14.913zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210826.1947 15.308zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210827.5030 151:c (Yutaka Maeda) 20210828.1876 15.252zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.1877 15.252zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.2713 15.354zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.2715 15.354zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.901 15.30C (Gary Poyner) 20210828.9028 15.22C (Masao Funada) 20210829.4567 157:cG (Yutaka Maeda) 20210830.8756 16.63C (Masao Funada) 20210831.2067 16.965zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210831.2069 16.965zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210831.4373 <164c (Yutaka Maeda) 20210831.5071 <166C (Masayuki Moriyama) 20210903.2085 17.666zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210903.2086 17.666zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210903.2667 17.995zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210905.1945 15.505zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210907.2273 15.298zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210907.2275 15.298zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210908.4314 155:c (Yutaka Maeda) 20210909.1497 15.498zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210909.4912 150cG (Yutaka Maeda) 20210911.1659 15.415zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210916.2071 18.551zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210919.1506 17.415zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210919.1749 17.114zr (Zwicky Transient Facility Lasair (Masci+ 2019))

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[vsnet-alert 26265] LL And: increase in the amplitude of superhumps
by Filipp Romanov 22 Sep '21

22 Sep '21

I reported (to the AAVSO and VSNET) my time-resolved V-band observations of LL And obtained remotely using 0.355-m f/6.2 Schmidt-Cassegrain telescope of Abbey Ridge Observatory (Canada). I clearly detected periodic superhumps with increasing amplitude: about 0.06 mag on September 20, about 0.10 mag on September 21 and about 0.25 mag on September 22. With best regards, Filipp.

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[vsnet-alert 26264] LL And: stage A superhumps and mass ratio
by Taichi Kato 22 Sep '21

22 Sep '21

LL And: stage A superhumps and mass ratio Kyoto U. team, Crimean Astrophys. Obs. team, Itoh-san, Alexandra Zubareva, Tonny Vanmunster, Tamas Tordai, Filipp Romanov and Kiyota-san have reported observations. The object started to show well-detectable superhumps since Sep. 20. The current period (stage A) is 0.0579(1) d. This period corresponds to q=0.143(5). This value is consistent with the result in https://ui.adsabs.harvard.edu/abs/2004PASJ...56S.135K/abstract This object is likely an SU UMa star (rather than a WZ Sge star) as judged from the mass ratio despite the very long supercycle. The lack of strong early superhumps appears to be consistent with this classification.

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