vsnet-alert March 2025

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

4 participants
3 discussions

[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

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[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/

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[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/>

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vsnet-alert March 2025