Abstract
A set of intermediate and low dispersion .spectra have been obtained of the Car II ("Keyhole") nebula, located to the north of 71 Carinae in NGC 3372 (= RCW 53), in order to search for clues on the origin of the high velocity components superimposed on the extended wings of the Ha and H lines reported by Elliott (1979) and their possible association with a supernova remnant. No apparent evidence of such a SNR is found in our spectra which closely resemble those of classical H II regions of moderate excitation. Although, the high velocity components in the Balmer lines are confirmed; it has been found that these components extend over a velocity range of ∼ 1150 km 1 A distinct blue continuum is detected in those spectra closer to 71 Carinae and the O3 star HDE , where light scattering is confirmed as the mechanism responsible for this effect. Stratification of material in different degrees of excitation is present over the whole region. Several models that might explain the high velocity structure of the Balmer lines in Car II and its vicinity are discussed.
