Spectroscopic classification of TCP J17394608-2457555 as a Galactic nova
ATel #10366; S. C. Williams (Lancaster), M. J. Darnley (LJMU)
on 11 May 2017; 11:04 UT
Credential Certification: Steven Williams (scw@astro.ljmu.ac.uk)
Subjects: Optical, Nova, Transient
We obtained a spectrum of the transient TCP J17394608-2457555 (see CBAT TOCP) under poor conditions (~4 arcsec seeing, some cloud) on 2017 May 11.15 UT. The spectrum was taken with the FRODOSpec spectrograph (Barnsley et al. 2012) on the 2-m Liverpool Telescope (LT; Steele et al. 2004), using the higher resolution mode, which gives a wavelength coverage of 3900 to 5100 Å and 5900 to 8000 Å, with a resolution of R ~ 5400.
The spectrum shows strong Hα emission, with a FWHM of 1400 km/s. The transient also shows O I (7774 Å) emission, which unlike Hα, has a strong P Cygni absorption profile. We identify Fe II lines at 6148, 6248 and 6456 Å, as well as C I (7115 Å). In addition to these permitted lines, [O I] 6300 and 6364 Å appear to be present.
This spectrum confirms TCP J17394608-2457555 is a Galactic nova eruption in Ophiuchus and a member of the Fe II spectroscopic class. The continuum is red and we do not detect features in the blue arm (i.e. 3900 to 5100 Å). This is consistent with significant reddening, as is the reported photometry on the CBAT TOCP.
