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

[vsnet-alert 26210] Re: ASASSN-21nv: at least four rebrightenings
by Taichi Kato 07 Sep '21

07 Sep '21

Re: ASASSN-21nv: at least four rebrightenings > The (super?)outburst started on 2021 July 27. A rapid fading began on August 23. > Short rebrightenings were recorded on August 27 and 30, and on September 2 and 4. > (according to ZTF, ATLAS and ASAS-SN data) Look like a short rebrightening and a long one (according to ZTF Lasair). ASAS-SN data are noisy (fainter thans around positive detections).

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[vsnet-alert 26209] ASASSN-21nv: at least four rebrightenings
by Patrick Schmeer 06 Sep '21

06 Sep '21

ASASSN-21nv (UGWZ:) https://www.aavso.org/vsx/index.php?view=detail.top&oid=2223860 ZTF light curve, data, and images (via Lasair): https://lasair.roe.ac.uk/object/ZTF21abouwjj/ Recent ASAS-SN Sky Patrol light curve and data: https://asas-sn.osu.edu/sky-patrol/coordinate/dc7c9a1a-df53-4dd2-8866-99e32… The (super?)outburst started on 2021 July 27. A rapid fading began on August 23. Short rebrightenings were recorded on August 27 and 30, and on September 2 and 4. (according to ZTF, ATLAS and ASAS-SN data) Time-resolved photometry was performed by Tonny Vanmunster (VMT) during six observing sessions (July 30 - Aug. 3 and Aug. 10 UT); no superhumps were detected: https://app.aavso.org/webobs/results/?star=ASASSN-21nv Follow-up observations are encouraged. Clear skies, Patrick ------- References: All-Sky Automated Survey for Supernovae (ASAS-SN) Sky Patrol: - Shappee et al., 2014ApJ...788...48S - Kochanek et al., 2017PASP..129j4502K Asteroid Terrestrial-impact Last Alert System (ATLAS): - Tonry et al., 2018PASP..130f4505T Lasair: - Smith et al., 2019RNAAS...3...26S Zwicky Transient Facility (ZTF): - Masci et al., 2019PASP..131a8003M

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[vsnet-alert 26207] MASTER OT J052622.61+734629.7: new SU UMa-type dwarf nova
by Taichi Kato 06 Sep '21

06 Sep '21

MASTER OT J052622.61+734629.7: new SU UMa-type dwarf nova Tamas Tordai and Josch Hambsch have reported observations. The object shows superhumps with a period of 0.06549(4) d and an amplitude of 0.28 mag.

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[vsnet-alert 26206] ASASSN-V J205543.90+240033.5: true period
by Taichi Kato 06 Sep '21

06 Sep '21

ASASSN-V J205543.90+240033.5 (AR Sco-like object): true period After an analysis of the ZTF data, I reached a conclusion that the true period is 0.523490(1) d. All the data can be well expressed by this period and the profile is sinusoidal (reflection type). The 10.803 d period I reported appears to be its alias. The initially reported 0.2-d period was caused by the incomplete phase coverage. Now this object looks even more similar to AR Sco (Porb=0.14853528 d, spin=1.95 min). I will publish a corrected report shortly. Special thanks to Elena Pavlenko for pointing out the likely error in the period.

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[vsnet-alert 26205] ASASSN-21qi: new SU UMa-type dwarf nova
by Taichi Kato 06 Sep '21

06 Sep '21

ASASSN-21qi: new SU UMa-type dwarf nova Berto Monard has reported observations. The object has been showing superhump (amplitude 0.18 mag) since Aug. 26. The period is 0.06141(2) d allowing aliases (alias still not selected due to the limited coverage).

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[vsnet-alert 26204] TCP J19092450+3041330: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 05 Sep '21

05 Sep '21

Dear colleagues, I have just finished analysing my unfiltered observations of TCP J19092450+3041330, obtained on 2021, September 04/05 at CBA Belgium Observatory (0.40-m f/10.0 telescope, QHY-268M CMOS, clear then clouds) and at CBA Extremadura Observatory (0.40-m f/5.1 telescope, SX-46 CCD, clear skies). Combining both observation sets, regular superhumps with an amplitude of 0.40 mag are clearly visible in the resulting light curve, establishing TCP J19092450+3041330 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 0.0680 +/- 0.0002d. The object was at mag CV = 16.1 on Sep 05th. 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 26198] SDSS J172102.48+273301.2: AM CVn object with double superoutburst
by Naoto Kojiguchi 05 Sep '21

05 Sep '21

SDSS J172102.48+273301.2: AM CVn object with double superoutburst Taguchi-san has reported the latest outburst of this object detected by ZTF alert. This object will soon show a second superoutburst. SC ~ 9.3 yr. Time-resolved photometry is required. YYYYMMDD(UT) mag observer comment 20210825.323 <16.677g ASN 20210826.196 15.852zr ZLR Start of outburst 20210826.217 15.659g ASN 20210827.277 16.078o ATF 20210827.319 15.813g ASN 20210828.195 15.757zg ZLR 20210828.211 15.764g ASN 20210828.258 16.124zr ZLR 20210829.044 15.935g ASN 20210829.275 16.140cy ATF 20210830.751 <16.748g ASN Start of dip 20210831.208 19.372zg ZLR 20210831.333 19.748o ATF ATF (ATLAS Forced Photometry (Tonry et al. 2018)) ASN (ASAS-SN survey (Shappee+ 2014; Kochanek+ 2017)) ZLR (Zwicky Transient Facility Lasair (Masci+ 2019))

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[vsnet-alert 26200] MASTER OT J052622.61+734629.7: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 04 Sep '21

04 Sep '21

Dear colleagues, I have just finished analysing my unfiltered CMOS observations of MASTER OT J052622.61+734629.7, obtained on 2021, September 03/04 at CBA Belgium Observatory, using a 0.40-m f/10.0 telescope and QHY-268M CMOS camera under clear skies. Regular superhumps with an amplitude of 0.29 mag are clearly visible in the resulting light curve, establishing MASTER OT J052622.61+734629.7 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 0.0665 +/- 0.0003d. The object was at mag CV = 16.2 on Sep 04th. 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 26197] ZTF21abwplpy: a CV candidate with large amplitude (> ~ 6 mag)
by Kenta TAGUCHI 03 Sep '21

03 Sep '21

Dear friends, Using my private system scraping MARS ( https://mars.lco.global/ ), I've just found ZTF21abwplpy 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.) Lasair: https://lasair.roe.ac.uk/object/ZTF21abwplpy/ ALeRCE: https://alerce.online/object/ZTF21abwplpy MARS: https://mars.lco.global/?objectId=ZTF21abwplpy According to ALeRCE, the position is (RA, Dec) = (19:15:25.637, -13:31:07.56) Last non-detections by ZTF: g > 20.5191 on 2021-08-29.21 (ZTF, 'difference mag' via ALeRCE) First detections by ZTF: g = 15.601 +/- 0.024 on 2021-09-01.17 (ZTF, 'difference mag' via ALeRCE) Second detections by ZTF: r = 16.369 +/- 0.045 on 2021-09-03.23 (ZTF, 'difference mag' via ALeRCE) g = 16.281 +/- 0.030 on 2021-09-03.25 (ZTF, 'difference mag' via ALeRCE) The result of ASAS-SN Sky Patrol: https://asas-sn.osu.edu/sky-patrol/coordinate/1713e323-474d-437d-aa0b-d65df… It confirms a nearby star is contaminated. 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 26196] GV Psc superoutburst
by Taichi Kato 03 Sep '21

03 Sep '21

GV Psc superoutburst YYYYMMDD(UT) mag observer 20210819.8382 <157C (Masayuki Moriyama) 20210827.6968 144cG (Yutaka Maeda) 20210828.3626 14.328zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.4350 14.543zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.7488 146:c (Yutaka Maeda) 20210829.7482 144cG (Yutaka Maeda) 20210830.3472 14.47C (Masao Funada) 20210830.7361 143cG (Yutaka Maeda) 20210831.7216 145cG (Yutaka Maeda)

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