000002172 001__ 2172
000002172 005__ 20160706145627.0
000002172 0247_ $$2DOI$$a10.1051/0004-6361/201220421
000002172 037__ $$aASTROimport-329
000002172 100__ $$aLobel, A.
000002172 245__ $$aModelling the asymmetric wind of the luminous blue variable binary MWC 314
000002172 260__ $$c2013
000002172 520__ $$aAims: We present a spectroscopic analysis of MWC 314, a luminous blue variable (LBV) candidate with an extended bipolar nebula. The detailed spectroscopic variability is investigated to determine if MWC 314 is a massive binary system with a supersonically accelerating wind or a low-mass B[e] star. We compare the spectrum and spectral energy distribution to other LBVs (such as P Cyg) and find very similar physical wind properties, indicating strong kinship.  Methods: We combined long-term high-resolution optical spectroscopic monitoring and V-band photometric observations to determine the orbital elements and stellar parameters and to investigate the spectral variability with the orbital phases. We developed an advanced model of the large-scale wind-velocity and wind-density structure with 3-D radiative transfer calculations that fit the orbitally modulated P Cyg profile of He i λ5876, showing outflow velocities above 1000 km s-1. Results: We find that MWC 314 is a massive semi-detached binary system of ≃1.22 AU, observed at an inclination angle of i = 72.8° with an orbital period of 60.8 d and e = 0.23. The primary star is a low-vsini LBV candidate of m1 = 39.6 M⊙ and R1 = 86.8 R⊙. The detailed radiative transfer fits show that the geometry of wind density is asymmetric around the primary star with increased wind density by a factor of 3.3, which leads the orbit of the primary. The variable orientation causes the orbital modulation that is observed in absorption portions of P Cyg wind lines. Wind accretion in the system produces a circumbinary disc.  Conclusions: MWC 314 is in a crucial evolutionary phase of close binary systems, when the massive primary star has its H envelope being stripped and is losing mass to a circumbinary disc. MWC 314 is a key system for studying the evolutionary consequences of these effects. Table 1, Figs. 1-4, 9, 10, 14-16, 18-20, 23 are available in electronic form at http://www.aanda.org
000002172 700__ $$aGroh, J. H.
000002172 700__ $$aMartayan, C.
000002172 700__ $$aFrémat, Y.
000002172 700__ $$aTorres Dozinel, K.
000002172 700__ $$aRaskin, G.
000002172 700__ $$aVan Winckel, H.
000002172 700__ $$aPrins, S.
000002172 700__ $$aPessemier, W.
000002172 700__ $$aWaelkens, C.
000002172 700__ $$aHensberge, H.
000002172 700__ $$aDumortier, L.
000002172 700__ $$aJorissen, A.
000002172 700__ $$aVan Eck, S.
000002172 700__ $$aLehmann, H.
000002172 773__ $$cA16$$pAstronomy and Astrophysics$$v559$$y2013
000002172 85642 $$ahttp://esoads.eso.org/abs/2013A%26A...559A..16L
000002172 905__ $$apublished in
000002172 980__ $$aREFERD