Emission line spectra of Herbig-Haro objects.

Multichannel spectrometer and image-intensified dissector scanner spectrophotometric data were obtained for 12 Herbig-Haro nebulae. Optical emission line fluxes are presented for all, and electron temperature and electron density values are determined for 10 of the condensations. Inhomogeneities in the line-forming regions of the 10 H-H objects are indicated by the derived N(e)-T(e) diagrams, and empirical two-component density models are constructed to interpret the emission line spectra of the five brightest condensations. With the aid of these models, O I, O II, O III, N I, N II, S II, S III, Ca II, Ne III, C I, and Mg I ionic abundances are determined. In all observed nebulae, these abundances are consistent with cosmic Population I elemental abundances. Although gas phase depletions in the refractory elements may be expected for objects located in regions of recent star formation in which there are large concentrations of dust, there is no evidence for enhanced dust formation inside any Herbig-Haro object; this is illustrated by the derived normal cosmic abundances of Ca and Fe.