Description
The results of high-resolution optical spectroscopy obtained for a recently suggested LBV (luminous blue variable) candidate, MWC 314, are presented. Photospheric lines mostly of N II and S II have been found for the first time with a resolution of 0.4-0.8{AA}. They imply a N/O overabundance previously reported for AG and HR Car since no O II absorptions were detected. Nearly 400 emission lines have been identified in the spectrum between 4190 and 8864{AA} many of which appear double-peaked. No significant P Cygni type absorption components have been found for the optically thick Balmer lines. This suggests that the stellar wind of MWC 314 is non-spherical and the circumstellar envelope is viewed not edge on. The systemic velocity measured using the emission lines of ionized metals turned out to be 55km/s, which corresponds to a distance towards the object of 3.0+/-0.2kpc, according to the galactic rotation curve. Our analysis of the characteristics of both photospheric and wind lines resulted in an estimate of the object's T_eff_ of nearly 25000K, which, however, needs further improvement. The other stellar parameters were found to be as follows: Log(L_bol_/L_{sun}_)=6.1+/-0.3, R_star_=60^+30^_=10_R_{sun}_. Our study confirms that MWC 314 is one of the most luminous stars in the Milky Way.
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