March 2023 - vsnet-campaign-dn - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-campaign-dn 17101] ASASSN-VJ065237.19+243622.3: IW And star, similar to BO Cet?
by Taichi Kato 29 Mar '23

29 Mar '23

ASASSN-VJ065237.19+243622.3: IW And star, similar to BO Cet? ATLAS+ASAS-SNL+ATLAS data. IW And state in 2016-2019. In 2021 Oct. - 2022 Apr., standstill - brightening - fading - cycles of outbursts - long, bright outburst in 2022 Apr. similar to BO Cet. Although the data were not sufficient, this outburst may have been a superoutburst. The object is bright (15-16 mag) and observations are encouraged.

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[vsnet-campaign-dn 17100] SU UMa likely superoutburst
by Taichi Kato 29 Mar '23

29 Mar '23

SU UMa likely superoutburst (From supercycle) YYYYMMDD(UT) mag observer 20230319.5127 147C (Masayuki Moriyama) 20230319.8229 <141 (Jose Ripero) 20230320.3041 14.446o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.3099 14.560o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.3135 14.531o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.3216 14.724o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.3247 14.600o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.3265 14.618o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230321.8653 <144 (Eddy Muyllaert) 20230323.051 150 (Gary Poyner) 20230324.047 149 (Gary Poyner) 20230326.5921 133cG (Yutaka Maeda) 20230327.6137 114cG (Yutaka Maeda) 20230327.6514 119C (Masayuki Moriyama) 20230327.8326 115 (Eddy Muyllaert)

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[vsnet-campaign-dn 17099] SDSSJ100515.39+191108.0 superoutburst
by Taichi Kato 29 Mar '23

29 Mar '23

SDSSJ100515.39+191108.0 superoutburst YYYYMMDD(UT) mag observer 20230320.1142 <187C (Masao Funada) 20230321.953 <17.30C (Gary Poyner) 20230321.9542 <185C (Masao Funada) 20230326.6222 <149c (Yutaka Maeda) 20230327.6384 125cG (Yutaka Maeda)

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[vsnet-campaign-dn 17098] MASTER OT J174816.22+501723.3 superhumps
by Taichi Kato 29 Mar '23

29 Mar '23

MASTER OT J174816.22+501723.3 superhumps Tamas Tordai's observations indeed recorded superhumps (Mar. 27-28).

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[vsnet-campaign-dn 17097] V1251 Cyg outburst (first since 2008)
by Taichi Kato 29 Mar '23

29 Mar '23

V1251 Cyg outburst (first since 2008) This is obviously an alert matter. YYYYMMDD(UT) mag observer 20230314.8506 <166C (Masayuki Moriyama) 20230318.8577 <155C (Masayuki Moriyama) 20230319.8561 <162C (Masayuki Moriyama) 20230327.8551 <159C (Masayuki Moriyama) 20230328.7938 14.29C (Masayuki Moriyama) Last superoutburst in 2008 and earlier ones in 1994 and 1997. Considering a supercycle of 11 years, the next superoutburst is overdue. The current outburst was detected early and time-resolved photometry is very desirable. This object is a long-Porb WZ Sge star and early superhumps were visible in the earliest state of a superoutburst.

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[vsnet-campaign-dn 17096] V793 Ara: dwarf nova
by Taichi Kato 28 Mar '23

28 Mar '23

V793 Ara: dwarf nova From ATLAS data. Light curve is relatively regular and an SU UMa star cannot be excluded. Cycle of bright outburst about 80 d. Next long one is expected in late May. Bright object (above 15 mag at peak).

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[vsnet-campaign-dn 17095] Re: TCPJ06461075+2502415 brightening!
by Taichi Kato 28 Mar '23

28 Mar '23

Re: TCPJ06461075+2502415 brightening! > Sano-san has reported that this object brightened above > 15 mag and was apparently still brightening on Mar. 27. This turned out to be an error.

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[vsnet-campaign-dn 17094] ASASSN-23bx: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 28 Mar '23

28 Mar '23

Dear colleagues, I have just finished analysing my unfiltered CCD observations of ASASSN-23bx, obtained on 2023, Mar 27/28 at CBA Extremadura Observatory (Spain) using a 0.40-m f/5.1 telescope and SX-46 CCD camera under clear skies. The resulting light curve clearly shows the presence of regular superhumps with a large amplitude of 0.58 mag, establishing ASASSN-23bx as a new SU UMa-type dwarf nova. A period analysis, using the ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and Conditional Entropy methods (Peranso 3.0) yields a combined superhump period of 0.0589 +/- 0.0005d. The object was at mag CV = 16.5 on Mar 28th. 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> http://www.cbabelgium.com PERANSO: The Light Curve and Period Analysis Software http://www.peranso.com

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[vsnet-campaign-dn 17093] TCPJ06461075+2502415 brightening!
by Taichi Kato 28 Mar '23

28 Mar '23

TCPJ06461075+2502415 brightening! Sano-san has reported that this object brightened above 15 mag and was apparently still brightening on Mar. 27. YYYYMMDD(UT) mag observer 20230327.4423 15.495B (Yasuo Sano) 20230327.4448 14.964V (Yasuo Sano) 20230327.4473 14.447Rc (Yasuo Sano) 20230327.4493 14.863C (Yasuo Sano) Time-resolved data did not show apparent superhumps reported by Vanmunster on Mar. 24. Such behavior is not expected in a WZ Sge after appearance of ordinary superhumps. Please continue your observations!

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[vsnet-campaign-dn 17092] MASTER OT J174816.22+501723.3 likely superoutburst
by Taichi Kato 27 Mar '23

27 Mar '23

MASTER OT J174816.22+501723.3 likely superoutburst YYYYMMDD(UT) mag observer 20230316.6432 19.087o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.5546 16.551o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.5737 16.919o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.5755 16.475o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230320.5845 16.346o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.5974 15.925o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.6220 15.853o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.6244 15.879o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.6280 15.814o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.6285 15.943o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.6333 15.985o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.6346 15.971o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230324.6437 15.973o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505))

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