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

[vsnet-newvar 8725] ASASSN-18hr likely superoutburst
by Taichi Kato 08 Sep '21

08 Sep '21

ASASSN-18hr likely superoutburst Suspected ER UMa star. YYYYMMDD(UT) mag observer 20210821.2250 18.820zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210821.3013 18.577zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210824.2447 16.184zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210824.3044 16.310zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210826.2604 16.232zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210826.2979 16.199zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.2131 16.321zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.2630 16.681zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210901.2677 16.462zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210903.2863 16.769zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210905.2440 17.136zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210905.2575 16.901zg (Zwicky Transient Facility Lasair (Masci+ 2019))

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[vsnet-newvar 8724] ZTF18aaakvdk: deeply eclipsing polar
by Taichi Kato 07 Sep '21

07 Sep '21

ZTF18aaakvdk: deeply eclipsing polar From ZTF data. Porb=0.0602840(1) d. Short, deep eclipses (1.4 mag). Approximate epoch BJD 2458754.802. The long-term light variation, low luminosity and red color support the polar classification. 2MASS 044925.788 +563930.63 (2000.0) 16.863 15.860 15.830 044925.6 +563931 (2000.0) ZTFJ044925.70+563931.2 r=19.490 (18.119-20.799) P=0.0603 044925.671 +563931.41 (2000.0) Gaia_DR2_274670550218199552 plx=2.728(0.686) dismod=7.8 pmra=8.495(1.132) pmdec=1.726(0.829) G=19.357 BP=19.538 RP=18.019 044925.767 +563930.43 (2000.0) Gaia_DR2_274670545924226560 plx=1.086(0.833) dismod=9.8 pmra=-3.974(1.138) pmdec=-7.457(1.028) G=20.040 BP=19.893 RP=18.330 044925.672 +563931.41 (2000.0) Gaia_EDR3_274670550218199552 plx=2.100(0.378) dismod=8.4 pmra=6.800(0.648) pmdec=1.679(0.374) G=19.242 BP=19.448 RP=18.055 044925.767 +563930.43 (2000.0) Gaia_EDR3_274670545924226560 plx=2.297(0.686) dismod=8.2 pmra=-3.499(0.877) pmdec=-7.294(0.667) G=19.982 BP=20.191 RP=18.438

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[vsnet-newvar 8723] 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-newvar 8722] 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-newvar 8720] 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-newvar 8719] 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-newvar 8718] 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-newvar 8716] Re: SDSS J172102.48+273301.2: AM CVn object with double superoutburst
by Patrick Schmeer 05 Sep '21

05 Sep '21

SDSS J172102.48+273301.2 (AM CVn star) https://www.aavso.org/vsx/index.php?view=detail.top&oid=233123 The second part of the current double superoutburst began on (or shortly before) September 3, according to ZTF (and ATLAS) data: https://lasair.roe.ac.uk/object/ZTF21abvdxkq/ The 2012 superoutburst had started between May 27 and June 5 (Denis Denisenko, vsnet-alert 14657). Time-resolved photometry during the current superoutburst is required. Clear skies, Patrick -------------------- Naoto Kojiguchi wrote on Friday, 3 September 2021 at 17:22:22 UTC: 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-newvar 8714] MASTER OT J052622.61+734629.7 rare outburst
by Taichi Kato 03 Sep '21

03 Sep '21

MASTER OT J052622.61+734629.7 rare outburst YYYYMMDD(UT) mag observer 20210828.8371 <157c (Yutaka Maeda) 20210829.8363 157:c (Yutaka Maeda) 20210830.8214 157:c (Yutaka Maeda) 20210831.1772 15.96C (Masao Funada) 20210831.8063 153:cG (Yutaka Maeda)

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[vsnet-newvar 8713] CRTS J221232.0+160140 possible superoutburst
by Taichi Kato 03 Sep '21

03 Sep '21

CRTS J221232.0+160140 possible superoutburst Superoutburst in 2011 May. Interval too short? YYYYMMDD(UT) mag observer 20210805.7168 <158c (Yutaka Maeda) 20210814.3037 20.013zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210828.7130 <138c (Yutaka Maeda) 20210829.5883 <166c (Yutaka Maeda) 20210831.5707 144:cG (Yutaka Maeda)

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vsnet-newvar September 2021