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Title: Optical and near-infrared data and modelling of nova V5668 Sgr
ABSTRACT

We present Hubble Space Telescope optical images, Keck-OSIRIS near-infrared (NIR) integral field spectroscopy data cubes and Keck-Near InfraRed Camera-2 (NIRC2) NIR images of nova V5668 Sgr from 2016 to 2019. The observations indicate enhanced emission at the polar caps and equatorial torus for low-ionization lines, and enhanced high-ionization emission lines only at the polar caps. The radial velocities are compatible with a homogeneous expansion velocity of v = 590 km s−1 and a system inclination angle of 24°. These values were used to estimate an expansion parallax distance of 1200 ± 400 pc. The NIRC2 data indicate the presence of dust in 2016 and 2017, but no dust emission could be detected in 2019. The observational data were used for assembling 3D photoionization models of the ejecta. The model results indicate that the central source has a temperature of 1.88 × 105 K and a luminosity of 1.6 × 1035 erg s−1 in August of 2017 (2.4 yr post eruption), and that the shell has a mass of 6.3 × 10−5 M⊙. The models also suggest anisotropy of the ionizing flux, possibly by the contribution from a luminous accretion disc.

 
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Award ID(s):
1751874
NSF-PAR ID:
10362616
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
511
Issue:
2
ISSN:
0035-8711
Page Range / eLocation ID:
p. 1591-1600
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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