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

[vsnet-alert 28060] 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 ----------------------------------------------

1 0

[vsnet-alert 28059] 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 ----------------------------------------------

1 0

[vsnet-alert 28055] 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 ----------------------------------------------

1 1

[vsnet-alert 28057] V854 Cen Apparent Decline
by Peter Williams 11 Apr '25

11 Apr '25

The bright southern RCB star V854 Cen appears to have commenced a decline as per the following visual observations: CENV854 20250312.780 74 WPX 10x50mm CENV854 20250402.445 80 WPX 10x50mm CENV854 20250411.465 93 WPX 20x80mm Full Moon Tks and regards Peter Williams Heathcote NSW

1 0

[vsnet-alert 28056] X Ser in outburst
by Robert J. Modic 09 Apr '25

09 Apr '25

CCD Observations Object YYYYMMDD(UT) Mag Obs Chart Remarks SERX 20250408.305 15.72B MRV AAVSO MPO61; Err 0.03; Outburst SERX 20250408.313 15.52V MRV AAVSO MPO61; Err 0.02; Outburst Instruments: RCOS 24" w/FLI PL1603, AAVSONet (MPO61) Observer: Robert J. Modic (MRV)

1 0

[vsnet-alert 28054] 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/>

1 0

[vsnet-alert 28053] outburst of LINEAR 23795703 - a CV of uncertain type in UMa
by Kirill Sokolovsky 25 Mar '25

25 Mar '25

The object LINEAR 23795703 = Gaia DR3 861540207303947776 = P_2.74a is listed as EW with the range 16.41 - 16.94 CV in the VSX https://www.aavso.org/vsx/index.php?view=detail.top&oid=322585 However, El-Badry et al. (2021) https://ui.adsabs.harvard.edu/abs/2021MNRAS.508.4106E/abstract identified it as an eclipsing cataclysmic variable (their object P_2.74a) that showed an outburst in 2015 according to ASAS-SN. El-Badry et al also present a spectrum and radial velocity curve. LINEAR 23795703 was found in outburst again on 2025-03-25.8886 UTC having CV=14.0 +/-0.1 in NMW survey images (135mm f/2.0 telephoto lens + unfiltered ST-8300M CCD). Best wishes, Kirill Sokolovsky for the NMW team

1 0

[vsnet-alert 28052] EX Hya in outburst
by Rod Stubbings 13 Mar '25

13 Mar '25

EX Hya in outburst (NLDQ(UG)+E) HYAEX 250310.486 130 HYAEX 250313.469 106 HYAEX 250313.569 106 -- Rod Stubbings Tetoora Road Observatory Victoria, Australia Honorary Associate member Astronomical Society of Australia Telescope: "Infinity" 22" f/3.8 stubbo(a)dcsi.net.au http://rodstubbingsobservatory.wordpress.com/

1 0

[vsnet-alert 28050] 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/>

2 1

[vsnet-alert 28049] 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 ----------------------------------------------

1 0