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[vsnet-campaign-dn 17517] ZTF18acynctq = TCP J20402089+4915562 = ASASSN-25bt: new SU UMa star candidate
by Yusuke Tampo 20 May '25

20 May '25

ZTF18acynctq = TCP J20402089+4915562 = ASASSN-25bt: new SU UMa star candidate XOSS team via TOCP/TNS and ASAS-SN reported the 2025 outburst of this system, which is already known as ZTF18acynctq in its 2018 outburst. https://alerce.online/object/ZTF18acynctq http://www.cbat.eps.harvard.edu/unconf/followups/J20402089+4915562.html https://www.aavso.org/vsx/index.php?view=detail.top&oid=10848612 Its 2018 outburst lasted for ~15 days and showed a possible rebrightening in the ATLAS data. Thus the outburst cycle is ~2300 d. This system is currently ~16.0 mag, and time-resolved observations may detect superhumps. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-campaign-dn 17516] TCP J19065629+4019093: new SU UMa-type dwarf novae and WZ Sge-type candidate
by Yusuke Tampo 11 May '25

11 May '25

TCP J19065629+4019093: new SU UMa-type dwarf novae and WZ Sge-type candidate TCP J19065629+4019093 was discovered by Y. Nakamura on 29th April, 2025, at 13.1 mag. S. M. Brincat, J. Hambsch, Itoh-san, T. Tordai, and Sano-san have reported the time-resolved observations of this new transient. The latest time-resolved observations on 9th May by S. M. Brincat report the presence of single-peaked superhumps with ~0.056 d. Thus TCP J19065629+4019093 is a new SU UMa-type dwarf nova. Taking into account this late (~10 d) appearance of superhumps, TCP J19065629+4019093 is likely a face-on WZ Sge-type dwarf nova. Further observations are encouraged to determine its superhump period. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-campaign-dn 17515] TCP J13560585+3727068: new WZ Sge-type dwarf nova
by Yusuke Tampo 30 Apr '25

30 Apr '25

TCP J13560585+3727068: new WZ Sge-type dwarf nova TCP J13560585+3727068 was discovered on 2025 04 26.7039 (UTC) at 14.3 mag (unfiltered). GIven the possible counterpart of Gaia G~20.8 and peak in ASAS-SN around 13.5 mag on 2025 04 24, the outburst amplitude is ~7.3 mag Itoh-san reported the time-resolved observations of TCP J13560585+3727068 on 2024 04 28 and 29. The light curve shows double-peaked modulations with the tentative period is 0.0574(1) d (aliases are possible) with ~0.04-mag amplitude. Thus, TCP J13560585+3727068 is likely a new WZ Sge-type dwarf nova. http://www.cbat.eps.harvard.edu/unconf/followups/J13560585+3727068.html https://asas-sn.osu.edu/sky-patrol/coordinate/19dd78d4-1819-43b4-bb38-be83e… Time-resolved observations are encouraged. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-campaign-dn 17512] TCP J08374922+0134065: new WZ Sge-type dwarf nova with large early superhump amplitude
by Yusuke Tampo 14 Apr '25

14 Apr '25

TCP J08374922+0134065: new WZ Sge-type dwarf nova with large early superhump amplitude TCP J08374922+0134065 was discovered by Y. Nakamura on 3rd April at 14.7 mag. Based on the suggested counterpart (GALEX J083749.2+013407) with g=20.22(2) and the brightest ASAS-SN measurement with g~13.4 mag, the outburst amplitude is 6.8mag. http://www.cbat.eps.harvard.edu/unconf/followups/J08374922+0134065.html https://asas-sn.osu.edu/sky-patrol/coordinate/dce846f3-485d-4614-bace-a8b3e… Itoh-san has reported the time-resolved observations on 6th April and the light curve shows a double-peaked modulation with a period of ~0.059 d and an amplitude of 0.2 mag with possible eclipses. Thus TCP J08374922+0134065 is a new WZ Sge-type dwarf nova with high inclination. Time-resolved observations are strongly encouraged. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-campaign-dn 17511] TCP J06455595+1210577: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 02 Apr '25

02 Apr '25

Dear colleagues, I have just completed the analysis of my unfiltered CCD observations of TCP J06455595+1210577, obtained on Apr 01/02, 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. This object was recently discovered by XOSS and announced as a possible CV candidate (see http://www.cbat.eps.harvard.edu/unconf/followups/J06455595+1210577.html) The light curve clearly reveals the presence of regular superhumps with an amplitude of 0.29 mag, establishing TCP J06455595+1210577 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 0.0731 +/- 0.0014d. The object was measured at mag CV = 16.2 on Apr 01st. Image calibration and photometry were performed using Phoranso, allowing me to simultaneously measure 4 other variables within the field of view of TCP J06455595+1210577. 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 17509] TCP J14034008+7947313: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 08 Mar '25

08 Mar '25

Dear colleagues, I have just finished analysing my unfiltered CCD observations of TCP J14034008+7947313, obtained over the past 7 nights between 2025, Feb 28 and Mar 06 at CBA Belgium Observatory using a 0.40-m f/10.0 telescope and QHY-268M CMOS camera under clear skies. No superhumps were visible in the light curves of this object till 2025, Mar 6/7. The light curve of 2025, Mar 6/7 clearly shows the presence of regular superhumps with an amplitude of 0.18 mag, establishing TCP J14034008+7947313 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 0.0586 +/- 0.0003d. The object was at mag CV = 15.3 on Mar 06th. Image calibration and photometry were done using Phoranso, which allows to simultaneously measure other variables present in the FOV of a variable star. I will send 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 17508] TCP J07222683+6220548: AM CVn star showing a superoutburst
by Yusuke Tampo 28 Feb '25

28 Feb '25

TCP J07222683+6220548: AM CVn star showing a superoutburst The time-resolved observations of TCP J07222683+6220548 aka ZTF25aacfjde have been repoted by Itoh-san, Sano-san, Josch Hambsch and Tamás Tordai. This object showed a 4-mag dip in the middle of the outburst, and time-resolved observations by Itoh-san after the recovery from this dip detected single-peaked variations with a period of 0.03256(2) d, likely an ordinary superhump. Thus TCP J07222683+6220548 is a new AM CVn star showing a superoutburst. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-campaign-dn 17503] TCP J04272195-2528038; possibly a new AM CVn star in outburst?
by Yusuke Tampo 02 Feb '25

02 Feb '25

TCP J04272195-2528038; possibly a new AM CVn star in outburst? TCP J04272195-2528038 was discovered by Y. Nakamura on 2025-01-09.4837 UT at 14.2 mag. The quiescence counterpart is g_PS1=21.09(5) mag, thus outburst amplitude is ~7 mag. http://www.cbat.eps.harvard.edu/unconf/followups/J04272195-2528038.html https://www.aavso.org/vsx/index.php?view=detail.top&oid=2391199 Itoh-san and myself using the SAAO/Lesedi telescope have reported the time-resolved observations. The SAAO data shows a possible double-peaked modulation with a period of ~42.6 min. In addition, the optical spectrum I obtained with the 1.9m telescope at the SAAO shows only the He I absorption lines, lacking any significant Balmer emission/absorption lines. Further observations are encouraged to establish its classification and determine the variation period. Best regards, Yusuke -- ---------------------------------------------- South African Astronomical Observatory, Postdoc fellow 反保雄介 Yusuke TAMPO MAIL: tampo(a)kusastro.kyoto-u.ac.jp MAIL: yusuke(a)saao.ac.za ----------------------------------------------

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[vsnet-campaign-dn 17502] TCP J17374270+4915116: new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 30 Dec '24

30 Dec '24

Dear colleagues, I have just finished analysing my unfiltered CCD observations of TCP J17374270+4915116, obtained over the past 7 nights between 2024, Dec 23/24 and 29/30 at CBA Extremadura Observatory (Spain) using a 0.40-m f/5.1 telescope and SX-46 CCD camera under clear skies. The object started to develop superhumps on Dec 28/29, which further developed on Dec 29/30. The resulting light curve clearly shows the presence of regular superhumps with an amplitude of 0.25 mag, establishing TCP J17374270+4915116 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 0.0589 +/- 0.0002d. The object was at mag CV = 14.6 on Dec 30th. Image calibration and photometry were done using Phoranso, which allowed me to simultaenously measure other variables present in the FOV of this new SU UMa-type dwarf nova. I will send 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 *** NEW *** http://www.phoranso.com <http://www.phoranso.com/>

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[vsnet-campaign-dn 17501] TCP J03493487+3607319 (aka ASASSN-24hf): new SU UMa-type dwarf nova
by tonny.vanmunster＠gmail.com 26 Dec '24

26 Dec '24

Dear colleagues, I have just finished analysing my unfiltered CCD observations of TCP J03493487+3607319 (aka ASASSN-24hf), obtained on 2024, Dec 23/24, 24/25 and 25/26 at CBA Extremadura Observatory (Spain) using a 0.40-m f/5.1 telescope and SX-46 CCD camera under clear skies. The resulting light curve clearly shows the presence of regular superhumps with an amplitude of 0.23 mag, establishing TCP J03493487+3607319 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 0.0697 +/- 0.0002d. The object was at mag CV = 16.7 on Dec 26th. Image calibration and photometry were done using Phoranso, which allowed me to simultaenously measure other variables present in the FOV of this new SU UMa-type dwarf nova. I will send 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 *** NEW *** http://www.phoranso.com <http://www.phoranso.com/>

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