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

[vsnet-alert 26336] XM78HT: period of early superhumps
by Taichi Kato 21 Oct '21

21 Oct '21

XM78HT: period of early superhumps Tonny Vanmunster and Itoh-san have reported observations. The amplitudes of early superhumps have decreased. The mean period up to now is 0.05413(6) d.

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[vsnet-alert 26335] ASASSN-21tg: superhump period
by Taichi Kato 20 Oct '21

20 Oct '21

ASASSN-21tg: superhump period Josch Hambsch has reported further observations. The amplitude of superhumps has grown (now more than 0.3 mag). The current superhump period is 0.0939(1) d (stage A).

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[vsnet-alert 26334] ASASSN-21tg: new SU UMa-type dwarf nova
by Taichi Kato 19 Oct '21

19 Oct '21

ASASSN-21tg: new SU UMa-type dwarf nova Josch Hambsch has reported further observations. The object showed superhumps on Oct. 17. The period is not well determined, but is close to 0.1 d. The current amplitude is 0.2 mag. The object is not an AM CVn star as initially suggested from the decline rate of the precursor. The very rapid deline for this orbital period is exceptional. Further observations are needed.

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[vsnet-alert 26333] XM78HT: new WZ Sge-type dwarf nova
by Taichi Kato 19 Oct '21

19 Oct '21

XM78HT: new WZ Sge-type dwarf nova Tonny Vanmunster has reported observations on two nights. The object showed early superhumps (double wave) with a period of 0.05404(4) d and an amplitude of 0.055 mag.

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[vsnet-alert 26332] XM78HT (= AT 2021abog): large-amplitude dwarf nova outburst (mag. 13.5, in Andromeda)
by Patrick Schmeer 18 Oct '21

18 Oct '21

XM78HT = AT 2021abog (UG) https://www.aavso.org/vsx/index.php?view=detail.top&oid=2225109 The current outburst began on 2021 October 15 according to ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K) data: https://asas-sn.osu.edu/sky-patrol/coordinate/45247e54-7a67-4e39-b69d-21913… https://asas-sn.osu.edu/sky-patrol/coordinate/1520ddd9-d0f1-4592-9cf3-ac961… Time-resolved photometry is encouraged. Clear skies, Patrick

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[vsnet-alert 26331] ASASSN-21tg: brightened
by Taichi Kato 18 Oct '21

18 Oct '21

ASASSN-21tg: brightened Josch Hambsch has reported further observations. The object brightened again to 15 mag on Oct. 16 and probably reached a peak. A period near 0.0201 d is still detected.

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[vsnet-alert 26330] ZTF21achzkjo: a CV candidate with large amplitude (> ~ 6 mag)
by Kenta TAGUCHI 17 Oct '21

17 Oct '21

Dear friends, Using my private system scraping MARS ( https://mars.lco.global ), I've just found ZTF21achzkjo out as a CV candidate from the public ZTF data. Its amplitude is > ~ 6.0 mag (assuming the limiting mag of PS1-g is 21.6). (I'm sorry if someone has already discovered and reported it elsewhere.) Lasair: https://lasair.roe.ac.uk/object/ZTF21achzkjo ALeRCE: https://lasair.roe.ac.uk/object/ZTF21achzkjo MARS: https://mars.lco.global/?objectId=ZTF21achzkjo According to ALeRCE, the position is (RA, Dec) = (20:51:40.411, +32:02:24.42) Last non-detections by ZTF: r > 19.9806 on 2021-10-15.20 (ZTF, 'difference mag' via ALeRCE) g > 19.8502 on 2021-10-15.22 (ZTF, 'difference mag' via ALeRCE) First detections by ZTF: r = 15.862 +/- 0.030 on 2021-10-17.16 (ZTF, 'difference mag' via ALeRCE) g = 15.531 +/- 0.027 on 2021-10-17.20 (ZTF, 'difference mag' via ALeRCE) The result of ASAS-SN Sky Patrol: https://asas-sn.osu.edu/sky-patrol/coordinate/23aa601d-22a4-42f6-b93d-24c20… It looks a nearby star is contaminating, so it cannot confirm the current outburst. No known minor planets are found by the Minor Planet Checker ( https://www.minorplanetcenter.net/cgi-bin/checkmp.cgi ). Best Regards and Clear Skies, Kenta -- ________________________________________________________________ 田口健太　(TAGUCHI, Kenta) 京都大学大学院理学研究科宇宙物理学教室 (Department of Astronomy, Graduate School of Science, Kyoto University) kentagch(a)kusastro.kyoto-u.ac.jp <mailto:kentagch@kusastro.kyoto-u.ac.jp> 09090536980

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[vsnet-alert 26329] ASASSN-21tg: very rapid fading
by Taichi Kato 17 Oct '21

17 Oct '21

ASASSN-21tg: very rapid fading Josch Hambsch reported observations. The object faded from 16.6 to 17.4 between Oct. 14.975 to 15.100. The rapid fading suggests an AM CVn-type object. A period of 0.021(1) d has been detected, but this needs to be confirmed by further observations.

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[vsnet-alert 26328] Re: ASASSN-14cc
by Taichi Kato 16 Oct '21

16 Oct '21

Re: ASASSN-14cc Subject: [vsnet-outburst 27836] Re: ASASSN-14cc From: Patrick Schmeer via vsnet-outburst <vsnet-outburst(a)ooruri.kusastro.kyoto-u .ac.jp> Please also refer to https://arxiv.org/abs/2106.15104. The superhump period has been confirmed by TESS observations. A change in mass-transfer rate was also suggested.

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[vsnet-alert 26327] PNV J00444033+4113068: color in quiescence
by Taichi Kato 16 Oct '21

16 Oct '21

PNV J00444033+4113068: color in quiescence 004440.3 +411306 (2000.0) LGGS_J004440.35+411306.9 V=22.278 B-V=0.310 U-B=-0.627 V-R=0.059

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