The present sample gathers ellipticals between E0 and E4, together with S0s; it belongs to a larger sample for which the proportion of S0s had been deliberately enhanced in order to increase the bias toward large rotation velocities.
Most of these objects have a distance between and
Mpc
(for
), and eight of them are
at more than 55 Mpc. The absolute magnitudes are in the range
.
Catalog elements are found in Table 1 (click here); here, the integrated magnitude, the absolute magnitude, and the effective radius of the galaxies are from Prugniel & Simien (1997; hereafter PS97). Knowledge of the orientation of the major axis is required for a meaningful measurement of the rotation velocity; care has been taken to search the literature for the most reliable value of its position angle (PA), and when we found evidence for a significant twist of the isophotes, we adopted a PA representative of the inner region where spectroscopic data could be obtained. Table 1 (click here) gives the reference for the PA determination.
Our kinematical observations have been secured at the 1.93-m telescope of the
Observatoire de Haute-Provence, equipped with the CARELEC long-slit
spectrograph (Prugniel et al.
1992). The camera aperture ratio was f/2.6,
and the receptor was a Tektronix with
pixels of 27
m,
corresponding to a projected size of 1.2''. The selected setup provided a
wavelength range of
900 Å centered on Mg
, with
a FWHM resolution of 1.8 Å per pixel (i.e., 104 km s
at
Å). The slit width, projected onto the plane of the sky, was
2.2''.
In January 1995, a five-night observing run collected data on the major axis of our program galaxies. Typically, two 45-minute exposures were obtained for each object; this individual exposure time was considered long enough to ensure a sufficient S/N ratio on most galaxies, yet short enough to prevent the widening of the spectral lines due to flexures within the spectrograph. For NGC 2732 and NGC 4478, spectra along the minor axis were also obtained. Each night, several template stars of types ranging between G8III and K2III were observed.
The atmospheric conditions were variable, with a seeing disk between
2.5'' and 3.6'' (FWHM) for most objects, but up to for four of
them; with the exception of NGC 430, galaxies with
were not
observed when the seeing was poorer than 4''. The log of the observations
is given in Table 2 (click here).
Table 2: Log of observations
Table 3: Kinematical results