2. Galaxy sample
The analyses have been carried out using optical spectra in the range 3700-7000 Å of the following objects: (i) the interacting galaxies presented in DP97; (ii) the Seyfert 1 J 15.22 (Maza et al. 1994); (iii) the classical Seyfert 2 NGC 1068; (iv) the LINER AM 2054-433S (Donzelli & Ferreiro 1998); and (v) the H II regions R5, R10 and R1 of the Gumm 38a H II region complex, which show different states of excitation and have solar metallicity (Girardi et al. 1997, hereafter G97).
Spectra of the interacting galaxies, the LINER AM 2054-433S, and the Seyfert 1 J 15.22 were obtained with the REOSC Spectrograph with a Tektronix CCD, at the 2.25m Ritchey-Chretien telescope of CASLEO, San Juan, Argentina. The galaxies were observed using a slit 2.5´ long and 3" wide in the spectral range 3700-7000 Å, with spectral resolution of 3.3 Å. NGC 1068 and the Gumm 38a H II region complex were observed at the CTIO 1.0m telescope. The spectrograph plus 2D-Frutti detector provided spectra in the range 3700-7000 Å with a resolution of 7 Å; the slit length corresponds to 5.2´. We assume throughout this paper .
Additional details on the observation and data reduction, as well as reddening and radial velocity corrections can be found in DP97 for the interacting galaxies, and in G97 for the Gumm 38a H II region complex. Radial velocity and reddening for NGC 1068 were taken from RC3 (de Vaucouleurs et al. 1991); for J 15.22 and AM 2054-433S, the radial velocities were measured in the observed spectra, and the reddenings were interpolated from nearby galaxies (values taken from RC3). Typical examples of the interacting pairs of our sample are shown in Figs. 1 and 2.
© European Southern Observatory (ESO) 1999
Online publication: June 18, 1999