March 2026 - vsnet-alert - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-alert 28153] TCP J07264579-2745141 : new SU UMa-type dwarf nova, and possibly WZ Sge-type one
by Hiromasa Hoke 27 Mar '26

27 Mar '26

dear all, TCP J07264579-2745141 : new SU UMa-type dwarf nova, and possibly WZ Sge-type one Itagaki-san discovered TCP J07264579-2745141 on 2026-03-17.4417 UTC at 14.8 mag (unfiltered). According to VSX, this object's quiescence magnitude is g~21.6 thus, the outburst amplitude is ~7 mag. https://vsx.aavso.org/index.php?view=detail.top&oid=10872106 Josch Hambsch and Moriyama-san reported the time-resolved observations. These light curves (after 2026-3-19 UTC) show ordinary superhumps with an amplitude of ~0.2 mag and a period of 0.05475(3)d. Hence, TCP J07264579-2745141 is a new SU UMa-type dwarf nova. Due to the sparse coverage before March 19, we cannot judge if TCP J07264579-2745141 showed early superhumps. Given the large outburst amplitude and short superhump period, it can be a WZ Sge-type dwarf nova. Best regards, Hiromasa

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[vsnet-alert 28152] ASASSN-26bv: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 24 Mar '26

24 Mar '26

Dear colleagues, ASASSN-26bv was discovered by the ASAS-SN team on 2026 Mar 15.1 at mag g = 17.1. I have just completed the analysis of my unfiltered CCD time-series observations of ASASSN-26bv, obtained on 2026 Mar 22/23 and Mar 23/24 at CBA Extremadura Observatory. The data were acquired under clear skies with a 0.40-m f/5.1 telescope and a Moravian G2-4000 CCD camera. The combined light curve clearly shows regular superhump modulations with an amplitude of 0.45 mag. A period analysis using ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.1) yields a combined superhump period of 0.0565 +/- 0.0003d. The object was measured at mag CV = 16.6 on Mar 24th. Image calibration and photometry were carried out using the latest release of Phoranso, which enabled simultaneous photometry of additional variable stars in the same field of view. These results establish ASASSN-26bv as a new SU UMa-type dwarf nova. Further follow-up observations are encouraged to refine the superhump period and study its evolution. I will submit my observations to AAVSO, CBA and VSNET for further analysis. With kind regards, Tonny --- Tonny Vanmunster CBA Belgium Observatory CBA Extremadura Observatory http://www.cbabelgium.co <http://www.cbabelgium.com/> m

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[vsnet-alert 28151] TCP J07032576-1241401: updated superhump period
by Yusuke Tampo 16 Mar '26

16 Mar '26

TCP J07032576-1241401: updated superhump period Along with Peter Starr, Josch Hambsh and Itoh-san have reported the time-resolved observations of TCP J07032576-1241401. Using these data, the updated superhump period is 0.06661(1) d, roughly consistent with Peter Starr's previous estimate. ATLAS has detected multiple superoutbursts over the years, with an approximate superoutburst cycle of ~300 days. https://fallingstar-data.com/forcedphot/queue/3994466/ Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow Yusuke TAMPO / 反保雄介 EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-alert 28148] TCP J08011102-0343141; new WZ Sge-type dwarf nova
by Yusuke Tampo 11 Mar '26

11 Mar '26

TCP J08011102-0343141; new WZ Sge-type dwarf nova TCP J08011102-0343141 was discovered by the XOSS team on 2026 02 08.8 UT at 15.1 mag. http://www.cbat.eps.harvard.edu/unconf/followups/J08011102-0343141.html Itoh-san has reported the time-resolved observations of TCP J08011102-0343141. The light curve shows double-peaked modulation with a period of ~0.069 d and an amplitude of ~0.02 mag, although 1-d-aliased periods are still possible. Given its large outburst amplitude of ~8 mag, this is most likely early superhumps of a WZ Sge-type dwarf nova. I also obtained an optical spectrum of TCP J08011102-0343141 with the 1.9m telescope at the SAAO Sutherland Observatory on 2026 02 09 UT. The spectrum shows Balmer absorption lines, consistent with this classification. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow Yusuke TAMPO / 反保雄介 EMAIL: tampo(a)kusastro.kyoto-u.ac.jp ALT. EMAIL: yusuke(a)saao.ac.za ----------------------------------------------

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