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The first observations of a small subsample of HSS candidates were
conducted in January 1995 with the SAO 6m telescope.
The telescope was equipped with the 1024-channel photon counter detector
(IPCS) mounted on the medium resolution spectrograph SP-124 in the Nasmyth-1
focus (Drabek et al. 1986).
A 2'' diameter circular aperture was centered on the brightest part of
the target galaxy or on the star-like candidate, and a similar aperture was
placed 20'' off along the direction zenith-nadir to accumulate
simultaneously the night sky spectrum. The latter was subtracted during
the data reduction from the target spectrum. This set-up resulted in
a spectral coverage of
3700-5500 Å with a scale
1.8 Å/channel along the dispersion and a spectral resolution (FWHM) of
about 10 Å. The exposure time varied between 3 and 5 minutes depending on
the brightness.
The signal-to-noise ratios of these spectra are
5 in
the continuum at
5000 Å. The seeing was about 2''.
During the night we have observed spectrophotometric standards from the KPNO list (Massey et al. [1988]) which were used to correct the spectra of the program galaxies for the system spectral response. An He-Ne-Ar lamp was used for the wavelength calibration. A flat-field was accumulated every night before and after the observations and all spectra are corrected for the flat field after azimuth and modulation correction of the original 1024-channel arrays.