Longslit spectra were obtained with the 4 m Mayall telescope at Kitt Peak National Observatory in two runs in 1996 February and October. We used the R.C. spectrograph and the T2KB CCD chip with a spatial sampling of 0.7 arcsec/pixel. The slit width was set to 1.5 arcsec for all the observations. NGC 5135 and IC 3639 were observed in February 16 at paralactic angle (P.A=1738#8, and 1708#8 respectively) with the grating KPC-007, covering the spectral range from 3400 Å to 5800 Å with a dispersion of 1.39 Å/pixel. The integration time was 2400 s and 1800 s respectively, split in two exposures for each galaxy. The air mass was 2.8 and 2.1 for NGC 5135 and IC 3639 respectively.
NGC 7130 was observed in October 10 and 11 with the slit at paralactic angle using two different gratings. KPC-007 covering the spectral range from 3400 Å to 5800 Å at P.A=177 8#8. The dispersion was 1.39 Å/pixel and the integration time, split into two exposures, was 3000 s. The grating BL420 was used covering the spectral range from 7060 Å to 10100 Å with a dispersion of 1.52 Å/pixel. The integration time was 1800 s. The color filter GG495 was used to block the blue light. The air mass was 2.5.
The data were reduced using the FIGARO data processing software. Bias subtraction and flatfielding were performed in the usual way; a two dimensional wavelength calibration was done using ARC2D (Wilkins & Axon 1991). The spectra were corrected for atmospheric extinction using a curve appropriate for the observatory. The frames were flux calibrated using the standards HD 84937, BD 174708 and HD 19445 observed during the same nights with the same set up but with a 10 arcsec slit width. The frames were corrected for distortion along the spatial direction by using a second order polynomial fit to the spectral distribution of the peak continuum emission of the standard stars, and then applied to the galaxy frames. Sky subtraction was performed in every data frame using the the outermost spatial increments where no obvious emission from the galaxy was present. Finally, frames of the same wavelength range were co-added.
For subsequent analysis, we have binned the central-most 5 pixels along the slit. Thus, the spectra we discuss in this paper pertain to a region 1.5 by 3.5 arcsec in extent.