Spectroscopic classification of TCP J20210770+2914093 as a nova
ATel #14793; U. Munari (INAF Padova), A. Vagnozzi and P. Valisa (ANS Collaboration)
on 17 Jul 2021; 07:43 UT
Credential Certification: U. Munari (ulisse.munari@oapd.inaf.it)
The transient TCP J20210770+2914093 appears of CBAT Transient Object
Followup Reports as discovered on 2021 07 16.4919 UT at unfiltered magnitude
12.0, with photometry obtained by Seiichiro Kiyota (Kamagaya, Japan) on July
16.5647 UT listing B=13.13, V=12.28, Rc=11.68 and Ic=11.15 mag.
We have obtained a medium resolution spectrum of the transient on July
17.102 UT with the Stroncone 0.50m telescope equipped with a mk.III
Astrolight Instrument multi-mode spectrograph. The spectrum is
characterized by a rather flat continuum with prominent Balmer lines in
emission, showing a FWHM of 1700 km/s and a sharper (FWHM=890 km/s)
absorption superimposed on the blue wing, blue shifted by 1150 km/s from the
emission peak. Much weaker emissions are present at HeI 7065, 6678, 5876,
5015, and NII 5678 and 4651. The spectrum is that of a nova. The current
appearance would favor an He/N type. Should the nova still rise in brightness,
it could cool down to a FeII type by the time of maximum.
