Spectroscopic classification as a high velocity nova of transient AT 2026yvz in M31
ATel #17975; P. Ochner, C. Balcon (DFA-UNIPD), U. Munari (INAF Padova)
on 16 Aug 2026; 08:02 UT
Credential Certification: U. Munari (ulisse.munari@oapd.inaf.it)
Subjects: Optical, Cataclysmic Variable, Nova, Transient
Transient AT 2026yvz (PNV J00431729+4126486) was discovered by R. Fidrich and T. Tordai in M31 at an unfiltered magnitude of 16.8 at coordinates R.A. = 00 43 17.29, Decl. = +41 26 48.6 (J2000) on 2026 Aug 14.092 UT.
We obtained low-resolution spectra of the transient over two consecutive nights with the Asiago 1.22m telescope (range 3800-7900 Ang, dispersion 2.31 Ang/pix). On Aug 14.96 UT (mid-exposure) we exposed for 45 min, and on Aug 15.97 UT for 75 min. The spectra were corrected for bias, dark, and flat fields, sky-subtracted, wavelength-calibrated, and flux-calibrated using nearby spectrophotometric standards observed before and after the transient.
To partially suppress noise in the spectra without altering the profile of the very broad line profiles, we applied a Gaussian kernel of FWHM = 500 km/s.
The spectra can be viewed AT2026yvz.png">here.
The spectra can be viewed at this link.The spectra are clearly those of a high-velocity nova, with Halpha having an FWHM of 3400 km/s on Aug 14.96 UT and 4050 km/s on Aug 15.97 UT (corrected for the smoothing function). The spectrum is rapidly evolving as shown in the picture, and protracted monitoring is encouraged.
