Astron. Astrophys. 339, 34-40 (1998)

4. Optical spectroscopy

In 1995 international time was allocated at La Palma Observatory to the WENSS project, of which a small part was dedicated to bright galaxies. Here we report on the spectroscopic observations carried out with the Isaac Newton Telescope (INT). We used the R300V grating, covering the range 3800-7200 Å, and a slit of 220 µm (corresponding to 1.19 arcsec). The observing log is given in Table 2, where in column 1 we list the running number as in column 1 of Table 1. The spectra were reduced with the help of the IRAF package. The redshift data, which for most objects were determined for the first time, are given in Table 3, where we also list the presence or absence of emission lines (usually ). NEL in column 5 stands for narrow emission lines (if is indicated no other emission lines like [OIII] were detected). Emission lines were predominantly found in spiral galaxies, but with a few exceptions: the elliptical galaxy Zwicky 338.014 has a Seyfert 1.5 type spectrum ( and have weak broad components), while in emission is also present in the elliptical Zwicky 337.030. Redshift information is virtually complete for spiral galaxies with , but not for ellipticals ( % is still missing). A very modest effort will be needed in the near future to fill the gaps in redshift down to a red magnitude of 16. We give a Hubble diagram for those objects with known redshifts in Fig. 3.

Table 2. INT observing log

Table 3. Spectroscopic data

Fig. 3. redshift-magnitude relation for spirals and ellipticals with known redshift.

© European Southern Observatory (ESO) 1998

Online publication: September 30, 1998
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