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

[vsnet-campaign-dn 16986] ASASSN-23ba: updated period of early superhumps
by Taichi Kato 27 Feb '23

27 Feb '23

ASASSN-23ba: updated period of early superhumps The data are from Berto Monard, Peter Starr, Josch Hambsch and Itoh-san. The period is 0.05662(1) d.

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[vsnet-campaign-dn 16985] ASASSN-23aw: new SU UMa star
by Taichi Kato 27 Feb '23

27 Feb '23

ASASSN-23aw: new SU UMa star Using observations by Josch Hambsch, superhumps have developed since Feb. 23. The period is 0.0520(1) or 0.0549(1) d (rather difficult to determine due to the low sampling rate).

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[vsnet-campaign-dn 16984] ASASSN-23ax: rebrightening
by Taichi Kato 27 Feb '23

27 Feb '23

ASASSN-23ax: rebrightening Josch Hambsch detected a rebrightening on Feb. 26 after a dip of 2-3 d.

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[vsnet-campaign-dn 16983] Re: MASTER OT J055845.55+391533.4: new SU UMa-type dwarf nova
by Taichi Kato 25 Feb '23

25 Feb '23

Re: MASTER OT J055845.55+391533.4: new SU UMa-type dwarf nova > The resulting light curve clearly shows the presence of regular superhumps > (4 in total) with an amplitude of 0.20 mag, establishing MASTER OT > J055845.55+391533.4 as a new SU UMa-type dwarf nova. The object is unusual in that it almost regularly showed a deep dip during past outbursts. There were sometimes variations like oscillations after the dip, and the overall behavior resembles a double superoutburst. 2018 Apr., 2019 Mar.-Apr., 2020 May, 2021 Jan.-Feb., 2021 Sep. all showed this feature. There was, however, no fading tail looking like an AM CVn star. The number of normal outbursts was smaller than that of superoutbursts. Please continue observing, since a dip is expected within a week. Recording variation of superhumps during the entire course of a superoutburst is very important to see what is happening.

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[vsnet-campaign-dn 16982] MASTER OT J055845.55+391533.4: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 25 Feb '23

25 Feb '23

Dear colleagues, I have just finished analysing my unfiltered CCD observations of MASTER OT J055845.55+391533.4 obtained on 2023, Feb 22/23 at CBA Extremadura Observatory (Spain) using a 0.40-m f/5.1 telescope and SX-46 CCD camera under relatively clear skies. The resulting light curve clearly shows the presence of regular superhumps (4 in total) with an amplitude of 0.20 mag, establishing MASTER OT J055845.55+391533.4 as a new SU UMa-type dwarf nova. A period analysis, using the ANOVA, Generalized-Lomb-Scargle, PDM and Conditional Entropy methods (Peranso 3.0) yields a combined superhump period of 0.0553 +/- 0.0004d. The object was at mag CV = 14.4 on Feb 23rd. 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 16981] GDSJ0703457-063947: IW And star
by Taichi Kato 25 Feb '23

25 Feb '23

GDSJ0703457-063947: IW And star Using ATLAS forced photometry (Tonry et al. 2018; Shingles et al. 2021), this object turned out to be an IW And star (typical behavior in 2022). The variation was more heartbeat-like in 2020-2021, when the object was slightly brighter. This may be a suggestion of various IW And-type behavior depending on the mass-transfer rate.

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[vsnet-campaign-dn 16980] MASTER OT J055845.55+391533.4 superhumps?
by Taichi Kato 25 Feb '23

25 Feb '23

MASTER OT J055845.55+391533.4 superhumps? Kiyota-san reported observations. The data appear consistent with a longer superhump period of a hydrogen-rich system. The data, however, were not enough and more observations are needed (the outburst behavior is unusual for ar ordinary SU UMa star).

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[vsnet-campaign-dn 16979] MV Leo: unusual start of standstill
by Taichi Kato 24 Feb '23

24 Feb '23

MV Leo: unusual start of standstill Using ATLAS and ZTF data, I found that this object entered a standstill almost directly from a low state in 2020 Mar.-Apr. Such behavior is unexpected. This standstill ended with an outburst like an IW And star.

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[vsnet-campaign-dn 16978] 6dFg0002074-374917: deeply eclpsing likely SU UMa star
by Taichi Kato 24 Feb '23

24 Feb '23

6dFg0002074-374917: deeply eclpsing likely SU UMa star Using ATLAS forced photometry (Tonry et al. 2018; Shingles et al. 2021). Porb=0.0711838(1) d. 1.5-mag deep eclipses and orbital humps in quiescence. Likely superoutburst in 2020.

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[vsnet-campaign-dn 16977] ASASSN-14ak most likely superoutburst
by Taichi Kato 24 Feb '23

24 Feb '23

ASASSN-14ak most likely superoutburst (Porb=0.08869) YYYYMMDD(UT) mag observer 20230211.0933 18.240o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2114 17.939o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2142 17.992o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2195 18.049o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2255 17.917o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2295 17.910o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2304 17.840o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2630 17.972o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230212.2686 17.907o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230214.9525 18.172o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230214.9557 18.175o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230214.9634 18.088o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230214.9777 18.214o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1413 18.197c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1641 18.070c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1659 18.136c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1683 18.237c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1697 18.225c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1701 18.240c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1733 18.023c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230216.1872 18.179c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230220.1531 18.373c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230220.1567 18.391c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230220.1599 18.265c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230220.1662 18.319c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230222.9545 13.374o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230222.9577 13.372o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230222.9629 13.392o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230222.9729 13.376o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230223.487 133 (Rod Stubbings)

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