Spectroscopic study of direct and dust-scattered line emission in the HH 1-HH 2 system

The different basic components of the HH1/HH2 complex, including the HH1, HH2, the jet, and the diffuse radiating environment between HH1 and HH2 on the same long-slit spectra are studied. Large velocity dispersion occur within the HH objects or near them. In front of HH 1, the large velocity dispersion of the forbidden S II and forbidden O I is correlated with large blueshifts of these lines. These results indicate that in front of HH 1, light is scattered by dust which is essentially at rest and which 'sees' blueshifted lines form the rapidly approaching HH object. The results also show that under the geometrical conditions which hold for the HH1/HH2 complex, velocities of matter in the plane of the sky can indeed be determined from Doppler shifts of dust-scattered lines. The dependence of the electron density and line ratios on position and velocity are examined and used to identify line wings which are due to dust scattering. 50 refs.