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

[vsnet-alert 27472] DDE 139: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 01 Mar '23

01 Mar '23

Dear colleagues I have just finished analysing my unfiltered CCD observations of DDE 139 obtained on 2023, Feb 27/28 and Feb 28/Mar 01 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 shows the presence of regular superhumps with an amplitude of 0.38 mag, establishing DDE 139 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 0.0798 +/- 0.0004d. The object was at mag CV = 16.9 on Mar 01st. 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-alert 27471] Long-lasting plateau in SBS1108+574
by Taichi Kato 01 Mar '23

01 Mar '23

Long-lasting plateau in SBS1108+574 Using ATLAS forced photometry (Tonry et al. 2018; Shingles et al. 2021), I noticed this EI Psc-type object showed long-lasting during some of its superoutbursts. The shape of these superoutbursts somewhat looks like those of standstill-like phase of superoutbursts in some AM CVn-type outbursts (EI Psc stars are between hydrogen-rich and AM CVn stars and this is natural). The unusual behavior in MASTER OT J055845.55+391533.4 may be similarly explained.

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[vsnet-alert 27470] Re: Wils_SDSSJ124602.02-202302.4 superoutburst?
by Taichi Kato 01 Mar '23

01 Mar '23

Re: Wils_SDSSJ124602.02-202302.4 superoutburst? Indeed superoutburst. 20230220.2598 18.723c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230220.2620 18.520c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230220.2652 18.623c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230220.2702 18.826c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230221.6439 <145c (Yutaka Maeda) 20230223.0003 16.396o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230223.0022 16.456o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230223.0281 16.488o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230223.0339 16.526o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230224.2020 15.486c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230224.2038 15.453c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230224.2089 15.329c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230224.2143 15.217c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230225.6549 <149c (Yutaka Maeda) 20230225.7339 15.33C (Masayuki Moriyama) 20230226.6000 <147c (Yutaka Maeda) 20230226.7593 154C (Masayuki Moriyama) 20230227.0132 15.597o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230227.0173 15.596o (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230227.6021 <152c (Yutaka Maeda) 20230227.6157 159C (Masayuki Moriyama) 20230228.2570 15.533c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230228.2588 15.550c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505)) 20230228.2616 15.563c (ATLAS Forced Photometry (Tonry+2018, PASP 130, 064505))

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[vsnet-alert 27469] Wils_SDSSJ124602.02-202302.4 superoutburst?
by Taichi Kato 01 Mar '23

01 Mar '23

Wils_SDSSJ124602.02-202302.4 superoutburst? Known SU UMa star. YYYYMMDD(UT) mag observer 20230221.6439 <145c (Yutaka Maeda) 20230225.6549 <149c (Yutaka Maeda) 20230225.7339 15.33C (Masayuki Moriyama) 20230226.6000 <147c (Yutaka Maeda) 20230226.7593 154C (Masayuki Moriyama) 20230227.6021 <152c (Yutaka Maeda) 20230227.6157 159C (Masayuki Moriyama)

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[vsnet-alert 27467] ASASSN-17oz bright outburst
by Taichi Kato 01 Mar '23

01 Mar '23

ASASSN-17oz bright outburst (But SS Cyg star) YYYYMMDD(UT) mag observer 20230210.2020 17.351zg (ZTF Alert DC mag (Masci+ 2019)) 20230211.7193 165C (Masayuki Moriyama) 20230215.6003 165C (Masayuki Moriyama) 20230216.540 168C (Mitsutaka Hiraga) 20230217.1344 16.171zg (ZTF Alert DC mag (Masci+ 2019)) 20230217.1612 15.879zr (ZTF Alert DC mag (Masci+ 2019)) 20230221.566 160C (Mitsutaka Hiraga) 20230223.497 128C (Mitsutaka Hiraga) 20230224.521 129C (Mitsutaka Hiraga) 20230224.5890 131C (Masayuki Moriyama) 20230225.531 128C (Mitsutaka Hiraga) 20230226.496 132C (Mitsutaka Hiraga) 20230227.553 129C (Mitsutaka Hiraga)

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[vsnet-alert 27466] GQ CVn outburst
by Taichi Kato 01 Mar '23

01 Mar '23

GQ CVn outburst Known SU UMa star. YYYYMMDD(UT) mag observer 20230226.6098 <161c (Yutaka Maeda) 20230226.7849 <174C (Masayuki Moriyama) 20230227.6119 148cG (Yutaka Maeda) 20230227.6438 15.52C (Masayuki Moriyama)

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[vsnet-alert 27465] NSV24667
by Taichi Kato 01 Mar '23

01 Mar '23

NSV24667 True? YYYYMMDD(UT) mag observer 20220906.6000 <148c (Yutaka Maeda) 20220907.6100 <151c (Yutaka Maeda) 20220909.5400 <143c (Yutaka Maeda) 20220913.5200 <145c (Yutaka Maeda) 20220914.5598 <157c (Yutaka Maeda) 20220915.5900 <161c (Yutaka Maeda) 20220919.5531 <149c (Yutaka Maeda) 20220920.5786 <155c (Yutaka Maeda) 20220929.5653 <151c (Yutaka Maeda) 20230227.8481 123c (Yutaka Maeda)

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[vsnet-alert 27464] Re: MASTER OT J055845.55+391533.4 superhump period
by Taichi Kato 01 Mar '23

01 Mar '23

Re: MASTER OT J055845.55+391533.4 superhump period > The mean superhump period up to now is 0.05505(2) d. > Observers: Kiyota-san, Tonny Vanmunster and Kubodera-san. The amplitude is 0.10 mag.

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[vsnet-alert 27463] MASTER OT J055845.55+391533.4 superhump period
by Taichi Kato 01 Mar '23

01 Mar '23

MASTER OT J055845.55+391533.4 superhump period The mean superhump period up to now is 0.05505(2) d. Observers: Kiyota-san, Tonny Vanmunster and Kubodera-san.

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[vsnet-alert 27462] DDE139 variation
by Taichi Kato 01 Mar '23

01 Mar '23

DDE139 variation Tonny Vanmunster has reported observations. Relatively large-amplitude variations (0.3 mag) were detected. Periodicity is still unclear.

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