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

[vsnet-alert 26550] ASASSN-22as: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 28 Jan '22

28 Jan '22

Dear colleagues, I have been collecting unfiltered CCD observations of ASASSN-22as over the past 11 nights at CBA Extremadura Observatory, using a 0.40-m f/5.1 telescope and SX-46 CCD camera under mostly clear skies. The collected light curves did not show obvious periodic modulations, with the exception of last night Jan 27/28, 2022. Regular superhumps with an amplitude of 0.24 mag are finally visible, establishing ASASSN-22as 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 0.0651 +/- 0.0007d. The object was at mag CV = 16.4 on Jan 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 PERANSO : The Light Curve and Period Analysis Software http://www.peranso.com

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[vsnet-alert 26549] RZ Leo: rapid fading
by Junpei Ito 27 Jan '22

27 Jan '22

RZ Leo: rapid fading Further time-resolved observation has been reported by Itoh-san, Kiyota-san, Osaka Kyoiku U. team, Shawn Dvorak, Tamás Tordai, Stephen M.Brincat, Filipp Romanov, Vihorlat Observatory team, and Kyoto U. team. According to Stephen M.Brincat's data at 2022-01-27 00:02 UT, this object is 15.4 mag and ~1mag fainter than on 2022-01-26. Therefore, this object can be in rapid fading now. In the 2001 superoutburst, rebrightening was observed, short-lasting (type-C) rebrightening (Ishioka et al. 2001). In order to check the rebrightening profile, daily snapshots are encouraged. Best regards, Junpei

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[vsnet-alert 26547] MASTER OT J030227.28+191754.5: rapid fading
by Junpei Ito 24 Jan '22

24 Jan '22

MASTER OT J030227.28+191754.5: rapid fading The most recent data by Itoh-san, Osaka Kyoiku U. team, Tamás Tordai, Tonny Vanmunster, Josch Hambsch, Vihorlat Observatory team, Filipp Romanov, Shawn Dvorak, Alexandra M.Zubareva, and Kyoto U. team have reported time-resolved photometry and this object is still in outburst. This object is 15.969 mag with clear filter at 2022-01-22 14:47 UT. According to a quick look reported by Kyoto U. team at 2022-01-24 09:21 UT, this object is 16.62(7) mag with clear filter. Therefore, this object can be in rapid fading now. This object has the largest outburst amplitude and may show unique rebrightening. Daily snapshots are encouraged in order to check rebrightening. And once rebrightening appears, time-resolved observations are encouraged. Best regards, Junpei

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[vsnet-alert 26544] ASASSN-20pv: no major variations yet
by Taichi Kato 24 Jan '22

24 Jan '22

ASASSN-20pv: no major variations yet Josch Hambsch reported observations on two nights. No major variations were found. The object may be currently in early superhump phase.

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[vsnet-alert 26540] ASASSN-22ax
by Taichi Kato 24 Jan '22

24 Jan '22

ASASSN-22ax Bright CV detected early. ASASSN-22ax --- ------- 2:53:21.49 -13:34:9.3 2022-01-20.18 13.44 SDSS DSS VIZIER ------- CV candidate, matches to PS1 g=20.5, g>17.2 on 2022-01-18.27, g=15.9 on 2022-01-19.22, g=13.6 on 2022-01-20.12 ASASSN-22ax 20220118.27 <172g ASN ASASSN-22ax 20220119.22 159g ASN ASASSN-22ax 20220120.12 136g ASN 025321.486 -133408.83 (2000.0) Gaia_DR2_5157734725783900032 plx=-(-) dismod=- pmra=-(-) pmdec=-(-) G=20.639 BP=20.719 RP=20.478 025321.486 -133408.83 (2000.0) Gaia_EDR3_5157734725783900032 plx=-0.681(1.731) dismod=- pmra=-10.028(1.037) pmdec=-18.710(1.362) G=20.572 BP=20.396 RP=20.680 025321.479 -133408.51 (2000.0) GALEX_DR5_2920234851152954444 NUV=20.984(0.066) FUV=21.024(0.092)

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[vsnet-alert 26543] ASASSN-22as: new SU UMa (or even WZ Sge?) star in the period gap
by Taichi Kato 23 Jan '22

23 Jan '22

ASASSN-22as: new SU UMa (or even WZ Sge?) star in the period gap Tonny Vanmunster and Tamas Tordai have reported observations. I could find a period of 0.09974(9) d (full amplitude of 0.10 mag). The profile resembles that of early superhumps (doubly peaked, sharp minimum) rather than ordinary superhumps. It is also possible that these superhumps are stage A superhumps. If this is indeed a WZ Sge star, it is very unusual. Further observations are needed to follow the development of these superhumps.

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[vsnet-alert 26542] ASASSN-22aw: superhump period
by Taichi Kato 23 Jan '22

23 Jan '22

ASASSN-22aw: superhump period Tamas Tordai and Itoh-san have reported observations. The superhump period is 0.07196(9) d.

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[vsnet-alert 26541] ASASSN-22aw: most likely SU UMa star
by Taichi Kato 22 Jan '22

22 Jan '22

ASASSN-22aw: most likely SU UMa star Tamas Tordai has reported observations. There was a 0.4 mag hump (likely superhump). More observations are needed to determine the period.

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[vsnet-alert 26539] ASASSN-22au
by Taichi Kato 21 Jan '22

21 Jan '22

ASASSN-22au Large-amplitude outburst. ASASSN-22au --- ------- 7:56:28.53 -79:2:39.7 2022-01-16.36 13.76 SDSS DSS VIZIER ------- CV candidate, no Vizier match, g>17.8 on 2022-01-13.24, g=14.1 on 2022-01-16.30, g=14.3 on 2022-01-17.09, g=14.7 on 2022-01-18.81 ASASSN-22au 20220113.24 <178g ASN ASASSN-22au 20220116.30 141g ASN ASASSN-22au 20220117.09 143g ASN ASASSN-22au 20220118.81 147g ASN

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[vsnet-alert 26536] ASASSN-20pv outburst
by Rod Stubbings 20 Jan '22

20 Jan '22

ASASSN-20pv (UGSU/IBWD:) is in outburst ASASSN-20pv 220120.535 123 -- Rod Stubbings Tetoora Road Observatory Victoria, Australia Telescope: "Infinity" 22" f/3.8 stubbo(a)dcsi.net.au http://rodstubbingsobservatory.wordpress.com/

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