Spatially resolved spectra of HH1 and Burnham's nebula in the range lambda of between about 3700 A and 10830 A

Abstract

The authors have obtained spatially resolved spectra of HH1 and Burnham's Nebula covering the broad wavelength range 3700 Å ≤ λ ≤ 10830 Å. The observations were carried out using the "echellette mode" of the Casegrain spectrograph at the Calar Alto 3.5 m telescope and a CCD as detector. For HH1, the authors have detected, identified, and measured 175 emission lines, thereby increasing the number of known lines by a factor of ≡2.3. Newly detected lines include those of [Ar IV], [Ar III], [Cl II] and the Na D lines. A large number of [Fe II] lines has been studied. The spatial distributions of the emission in many lines has been determined. Electron temperatures are derived from line ratios of [C I], [O I], [N II], [S III] and [O III]. The results are in qualitative agreement with predictions from shock wave models. For Burnham's Nebula, the authors have now detected and measured 81 emission lines. They are all compatible with the emission from a moderate excitation HH object. The T<SUB>e</SUB> determinations show a variation with ionization stage similar to the variation found in the case of HH1, again indicating that the observed emission is compatible with model predictions for the recombination regions of shock waves.