A multi-wavelength view on the dusty Wolf-Rayet star WR 48a
Abstract
We present results from the first attempts to derive various physical characteristics of the dusty Wolf-Rayet star WR 48a based on a multi-wavelength view of its observational properties. This is done on the basis of new optical and near-infrared spectral observations and on data from various archives in the optical, radio and X-rays. The optical spectrum of WR 48a is acceptably well represented by a sum of two spectra: of a WR star of the WC8 type and of a WR star of the WN8h type. The strength of the interstellar absorption features in the optical spectra of WR 48a and the near-by stars D2-3 and D2-7 (both members of the open cluster Danks 2) indicates that WR 48a is located at a distance of ~4 kpc from us. WR 48a is very likely a thermal radio source and for such a case and smooth (no clumps) wind its radio emission suggests a relatively high mass-loss rate of this dusty WR star (dM/dt = a few x 10^(-4) solar masses per year). Long timescale (years) variability of WR 48a is established in the optical, radio and X-rays. Colliding stellar winds likely play a very important role in the physics of this object. However, some LBV-like (luminous blue variable) activity could not be excluded as well.
Keywords
Cite
@article{arxiv.1409.2684,
title = {A multi-wavelength view on the dusty Wolf-Rayet star WR 48a},
author = {Svetozar A. Zhekov and Toma Tomov and Marcin P. Gawronski and Leonid N. Georgiev and Jura Borissova and Radostin Kurtev and Marc Gagne and Marcin Hajduk},
journal= {arXiv preprint arXiv:1409.2684},
year = {2015}
}
Comments
Accepted for publication in MNRAS; 16 pages, 16 figures, 6 tables