THE BIPOLAR STRUCTURE OF THE LBV NEBULA AROUND HR CARINAE

HR Carinae is one of the few Luminous Blue Vari- ables (LBVs) in the Galaxy. It has a nebula that appears bipolar. Wehaveobtainedimagingandhigh-dispersion,long-slitechelle dataoftheHRCarnebula,andconrmedthatitisabipolarneb- ula. Its polar axis lies along the position angle of 1255; each lobe has, at a distance of 5kpc a diameter of 0:65pc and a line-of-sight expansion velocity of 75 150km s 1 . Beside the expanding bipolar lobes, a number of (Nii)- bright knots are detected. These knots have lower expansion ve- locitiesthanthelobesandaredetectedonlywithintheprojected boundary of the lobes. These knots are most likely nitrogen- enriched material ejected by HR Car. On a larger scale, a funnel-shaped nebula is detected at 2: 0 5 northwest of HR Car. The axis of the funnel is roughly aligned with the polar axis of the HR Car nebula, suggesting that HR Car may be responsible for the ionization and shaping of this nebula. Future observations of kinematics and abundances are needed to determine the nature of this nebula. We propose that the bipolar nebula of HR Car is a more evolved version of the Homunculus Nebula around Car. The recently developed theory of wind-compressed disks may ex- plainthehigherdensityoftheequatorialplaneandtheformation of bipolar nebulae of LBVs.