Investigation of [KSF2015] 1381-19L, a WC9-type star in the high extinction Galactic region

Abstract

We report a multi-wavelength study of the Wolf Rayet (WR) star: [KSF2015] 1381-19L, which is located in the solar metallicity region (Z=0.014) of the Milky Way Galaxy, strongly obscured by the interstellar dust. We perform a detailed characterization of the stellar atmosphere by fitting the spectral emission lines observed in the Optical and Near-InfraRed (NIR) bands, using CMFGEN. The best-fitted spectroscopic model indicates a highly luminous ($10^{5.89}{L}_{\odot }$) star with a larger radius ($15R_{\odot }$) and effective temperature, wind terminal velocity, and chemical composition similar to that of Galactic WC9-dusty (WC9d)-type stars. The atmospheric ionization structure shows coexisting ionization states of different elements, simultaneously affecting the opacity and thermal electron balance. Fitting of the spectral energy data (SED) reveals high interstellar optical extinction ($A_V=$ 8.87) while the IR extinction is found to be comparatively lower ($A_{K_s}=$ 0.98). We do not detect any excess emission at near-IR wavelengths due to dust. Upon comparison of our results with the GENEVA single star evolutionary models (Z=0.014), we identify the best possible progenitors ( a rotating star of $67M_{\odot }$ and a non-rotating star of $90M_{\odot }$).

15 pages, 8 figures and 10 tables

References in corpus (18)

• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• Gaia Data Release 3: Summary of the content and survey properties
• Physical Properties of Wolf-Rayet Stars
• Binary Population and Spectral Synthesis Version 2.1: construction, observational verification and new results
• The effect of massive binaries on stellar populations and supernova progenitors
• An Analysis of the Shapes of Interstellar Extinction Curves. VII. Milky Way Spectrophotometric Optical-through-Ultraviolet Extinction and Its R-Dependence
• The Galactic WC stars: Stellar parameters from spectral analyses indicate a new evolutionary sequence
• A multi-wavelength view on the dusty Wolf-Rayet star WR 48a
• One Relation for All Wavelengths: The Far-Ultraviolet to Mid-Infrared Milky Way Spectroscopic R(V) Dependent Dust Extinction Relationship
• Spatial distribution of Galactic Wolf-Rayet stars and implications for the global population
• Milky Way Mid-Infrared Spitzer Spectroscopic Extinction Curves: Continuum and Silicate Features
• Unlocking Galactic Wolf-Rayet stars with $\text{Gaia}$ DR2 I: Distances and absolute magnitudes
• Hoki: Making BPASS accessible through Python
• Grids of stellar models with rotation VII: Models from 0.8 to 300 M${}_{\odot }$ at super-solar metallicity (Z = 0.020)
• Line Luminosities of Galactic and Magellanic Cloud Wolf-Rayet stars
• Variable dust emission by WC type Wolf-Rayet stars observed in the NEOWISE-R survey
• The Physical Parameters of Four WC-type Wolf-Rayet Stars in the Large Magellanic Cloud: Evidence of Evolution
• Neon Abundances from a Spitzer/IRS Survey of Wolf-Rayet Stars