High-resolution optical spectroscopic monitoring observations of PNV J17224490-4137160 (Nova Sco 2023)
ATel #16007; L. Izzo (DARK/NBI), M. Della Valle (INAF/Naples), C. E. Woodward (U. Minnesota), P. Molaro (INAF/Trieste), S. Starrfield (ASU), R. M. Wagner (OSU/LBTO), E. Guido (Telescope Live), M. Cecconi, C. Padilla-Torres (FGG/INAF)
on 24 Apr 2023; 05:23 UT
Distributed as an Instant Email Notice Novae
Credential Certification: Luca Izzo (luca.izzo@gmail.com)
We have observed the recently discovered classical nova PNV J17224490-4137160 (Nova Sco 2023, ATel #16002, #16003, #16004, #16005, #16006) on April 23.14, 2023, with the High Accuracy Radial velocity Planet Searcher North (HARPS-N, prog. ID A47 TAC 29, PI: Della Valle) mounted at the 3.6 Telescopio Nazionale Galileo (TNG) located in La Palma, Spain. HARPS-N covers the wavelength range between 390 and 690 nm, with a resolving power of R = 115,000 (nominal velocity resolution of ~ 2.6 km/s). The total integration time was 900sec, obtained under good seeing conditions.
We report a very red spectral continuum (faint continuum below 430 nm; while exceptionally bright near 690 nm), suggesting a high extinction along the line of sight, as has been also reported in ATEL #16006. The detection of several intense DIBs absorption features, such as the 578.5 nm, and the 628.4 nm, whose equivalent widths suggest E(B-V) > 0.5 mag, (following the relations of Raimond et al. 2012, Phillips et al. 2013). The Na I D lines at 589.0/589.6 nm show three main saturated components spanning velocities from -5 to -51 km/s.
The spectrum is dominated by a bright Halpha line with P-Cygni broad (FWHM ~ 400 km/s) absorptions at blue-shifted velocities of v = -1800 and -3200 km/s. There are also fainter absorption features present at lower velocities (v ~ -450 km/s) located on the blue wing of the bright Halpha line. The brightest non-Balmer lines are Fe II 501.8 nm (multiplet 42) and Fe II 614.8/624.8 nm (multiplet 74). Fe II lines, in addition to Si II 635.5 nm. The Na I 568.6/589.0 nm shows only a single high-velocity component at v = -1800 km/s. The low-velocity component at v = -450 km/s is still detected in these lines, but fainter than in Balmer lines. In addition, present is an absorption feature at 581.3 nm that if associated with Na I 5890 would correspond to velocities of ~ -4000 km/s, which is higher than what is observed also in Balmer lines. Possibly, this absorption is associated with an emerging He I 587.6 nm component at v = -3200 km/s. Further detailed analysis is ongoing.
