October 2021 - vsnet-alert - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-alert 26341] ASASSN-21tr
by Taichi Kato 21 Oct '21

21 Oct '21

ASASSN-21tr Large outburst amplitude. ASASSN-21tr --- ------- 7:53:30.48 66:29:23.7 2021-10-21.36 14.56 SDSS DSS VIZIER ------- CV candidate, matches to SDSS g=22.2, g>17.3 on 2021-10-19.49, g=14.9 on 2021-10-21.36 ASASSN-21tr 20211019.49 <173g ASN ASASSN-21tr 20211021.36 149g ASN

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[vsnet-alert 26340] 1RXS J063214.8+253620
by Taichi Kato 21 Oct '21

21 Oct '21

1RXS J063214.8+253620 This object is a long-period SS Cyg star and does not require special time-resolved photometry. Using ZTF data, I obtained an orbital period of 0.324254(3) d (in agreement with Armstrong et al. 2016 using K2 data). The profile is double wave (ellipsoidal variation) + orbital hump, as expected for a low-Mdot SS Cyg star.

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[vsnet-alert 26339] MASTER OT J211656.91-432501.4: new SU UMa-type dwarf nova
by Taichi Kato 21 Oct '21

21 Oct '21

MASTER OT J211656.91-432501.4: new SU UMa-type dwarf nova Berto Monard reported observations. On Oct. 10, the object showed 0.3-mag superhumps. The period was about 0.06 d.

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[vsnet-alert 26337] Gaia19cws most likely superoutburst
by Taichi Kato 21 Oct '21

21 Oct '21

Gaia19cws most likely superoutburst Most likely SU UMa star with a short supercycle 140 d (from ZTF data). YYYYMMDD(UT) mag observer 20210927.3499 19.481zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210927.3924 20.037zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210929.2996 19.794zr (Zwicky Transient Facility Lasair (Masci+ 2019)) 20210929.3377 19.572zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20211010.3902 17.149zg (Zwicky Transient Facility Lasair (Masci+ 2019)) 20211014.4368 17.500zg (Zwicky Transient Facility Lasair (Masci+ 2019))

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[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 19 Oct '21

19 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 18 Oct '21

18 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 18 Oct '21

18 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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