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7 Summary

We have described in detail the data of the ESP galaxy redshift survey, which extends over about 23 square degrees, in a region near the South Galactic Pole. The survey is $\sim\! 85\%$ complete to the limiting magnitude $b_{\rm J}=19.4$ and consists of 3342 galaxies with redshift determination. Although not all galaxies have been observed and not all spectra have produced a measurable redshift, we have shown that these facts do not introduce any bias in the final spectroscopic sample. The only significant bias still remaining in the sample is due to the fact that close pairs of galaxies could not be observed in a single OPTOPUS (or MEFOS) observation. For this reason the fraction of not-observed objects is significantly higher than average for objects which have a companion in the photometric catalogue at a distance smaller than about 50 arcsec.

For all galaxies we have determined, when possible, both absorption and emission velocities. The median formal errors on the velocities are 64 and 31 km/s for the absorption and emission velocities, respectively. Analysis of the velocity measurements of the galaxies which have been observed more than once shows, however, that these formal errors are significant underestimates of the "true'' errors. In first approximation the true errors can be obtained by multiplying the formal ones by factors of the order of 1.5 and 2.1 for $v_{\rm abs}$ and $v_{\rm emiss}$, respectively.
The data of the catalogue, available in electronic form at the the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html, provide all the information which is needed (i.e. positions, magnitudes, velocities, completeness) for statistical analyses of this sample, as for example the estimate of the luminosity function and mean galaxy density (Zucca et al. 1997).

Acknowledgements

This work has been partially supported through NATO Grant CRG 920150, EEC Contract ERB-CHRX-CT92-0033, CNR Contract 95.01099.CT02 and by Institut National des Sciences de l'Univers and Cosmology GDR. It is a pleasure to thank the support we had from the ESO staff both in La Silla and in Garching. In particular, we are grateful to Gerardo Avila for his advice and his help in solving every instrumental problem we have been facing during this project. We also thank M. Kurtz and D. Mink who kindly provided the RVSAO package before the official release in IRAF.


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