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[vsnet-campaign-dn 17534] TCP J19335406+4220008: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 01 Jul '25

01 Jul '25

Dear colleagues, I have just completed the analysis of my unfiltered CCD observations of TCP J19335406+4220008, obtained on Jun 29/30 and Jun 30/Jul 01, 2025 at CBA Extremadura Observatory (Spain). The data was collected using a 0.40-m f/5.1 telescope and Moravian G2-4000 CCD camera under clear skies. The object was discovered by XOSS (Mi Zhang, Jianlin Xu, Guoyou Sun, Jiangao Ruan, et al.) on Jun 21st. The light curve clearly reveals the presence of regular superhumps with an amplitude of 0.13 mag, establishing TCP J19335406+4220008 as a new SU UMa-type dwarf nova. A period analysis, using the ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.1) yields a combined superhump period of 0.0615 +/- 0.0003d. The object was measured at mag CV = 14.9 on Jul 01st. Image calibration and photometry were performed using the latest release of Phoranso, allowing us to simultaneously collect observations of 4 additional interesting VSX stars in the same FOV. Further observations are encouraged to refine the superhump period. 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 PERANSO : The Light Curve and Period Analysis Software http://www.peranso.co <http://www.peranso.com/> m PHORANSO: Photometric Reduction and Analysis Software http://www.phoranso.com <http://www.phoranso.com/>

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[vsnet-campaign-dn 17533] ASASSN-25cu: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 29 Jun '25

29 Jun '25

Dear colleagues, I have just completed the analysis of my unfiltered CCD observations of ASASSN-25cu, obtained on Jun 27/28 and 28/29, 2025 at CBA Belgium Observatory. The data was collected using a 0.40-m f/10.0 telescope and QHY-268M CMOS camera under clear skies. The light curve clearly reveals the presence of regular superhumps with an amplitude of 0.25 mag, establishing ASASSN-25cu as a new SU UMa-type dwarf nova. A period analysis, using the ANOVA, Lomb-Scargle, Generalized-Lomb-Scargle and PDM methods (Peranso 3.1) yields a combined superhump period of 0.0536 +/- 0.0014d. The object was measured at mag CV = 15.7 on Jun 29th. Image calibration and photometry were performed using the latest release of Phoranso. Further observations are encouraged to refine the superhump period. 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 PERANSO : The Light Curve and Period Analysis Software http://www.peranso.co <http://www.peranso.com/> m PHORANSO: Photometric Reduction and Analysis Software http://www.phoranso.com <http://www.phoranso.com/>

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[vsnet-campaign-dn 17532] asassn-25ca, -25ce, -25ch at KKO
by Berto Monard 05 Jun '25

05 Jun '25

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[vsnet-campaign-dn 17531] TCP J20131357+1154031: new SU UMa-type dwarf nova, possibly WZ Sge-type
by Yusuke Tampo 03 Jun '25

03 Jun '25

TCP J20131357+1154031: new SU UMa-type dwarf nova, possibly WZ Sge-type K. Itagaki discovered TCP J20131357+1154031 on 2025-05-19 UTC at 14.7 mag (unfiltered). The outburst amplitude is ~8.4 mag. https://www.aavso.org/vsx/index.php?view=detail.top&oid=10848625 SAAO/Lesedi telescope, Josch Hambsch, and Sano-san have reported the time-resolved observations. Josch's observations after 28 May show single-peaked variation with a period of 0.05797(6) d, likely an ordinary superhump. No clear modulations were presented before this. Thus TCP J20131357+1154031 is a new SU UMa-type dwarf nova and a good candidate for a WZ Sge-type dwarf nova, given its late appearance of ordinary superhumps. 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-campaign-dn 17530] ASASSN-25ce: new WZ Sge-type dwarf nova
by Yusuke Tampo 02 Jun '25

02 Jun '25

ASASSN-25ce: new WZ Sge-type dwarf nova ASAS-SN discovered ASASSN-25ce on 2025-05-28 UTC at 12.26 mag. The Gaia counterpart is G~20.7 mag thus the outburst amplitude is ~8.5 mag. The SAAO team and Berto Monard reported the time-resolved observations. These light curves show a double-peak modulation with an amplitude of ~0.1 mag and a period of ~0.05537(1) d. The 5-sec resolution observations by the SAAO/Lesedi telescope also show QPO-like modulation with 5--10 min. Hence, ASASSN-25ce is a new WZ Sge-type dwarf nova, possibly with a relatively higher inclination, while no clear eclipses are present. Further time-resolved observations are encouraged. 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-campaign-dn 17529] asassn-25ca, -25ce on 31 May at KKO
by Berto Monard 01 Jun '25

01 Jun '25

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[vsnet-campaign-dn 17528] asassn-25ce at KKO
by Berto Monard 31 May '25

31 May '25

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[vsnet-campaign-dn 17527] asassn-25ca at KKO
by Berto Monard 31 May '25

31 May '25

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[vsnet-campaign-dn 17526] ASASSN-25ca: new SU UMa-type dwarf nova
by Yusuke Tampo 30 May '25

30 May '25

ASASSN-25ca: new SU UMa-type dwarf nova ASAS-SN reported ASASSN-25ca on 2025-05-20 at g=14.1. https://www.aavso.org/vsx/index.php?view=detail.top&oid=10848671 Berto Monard and Josch Hambsch reported the time-resolved observations of ASASSN-25ca. Their observations on 29 May show ordinary superhumps with a period of 0.0588(1) d. Observations on 27 May also show a hint of superhumps but the baseline was too short. Thus, ASASSN-25ca is a new SU UMa-type dwarf nova, and could be a WZ Sge-type based on its short superhump period, large outburst amplitude, and lack of previous outbursts. 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-campaign-dn 17525] ASASSN-15ca: SU UMa-type dwarf nova
by Yusuke Tampo 28 May '25

28 May '25

ASASSN-15ca: SU UMa-type dwarf nova According to ASAS-SN and Atlas, outbursts in Jan. 2015, Feb 2022, and May 2025 (as AT 2025mbw reported by MASTER). My observations with the SAAO/Lesedi telescope on 27 May 2025 detected superhumps with a period of ~0.0589(2) d. -- ---------------------------------------------- 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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