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3. Coverage and completeness

We have obtained reliable redshifts for 173 galaxies, with tentative redshifts for a further 36 objects, as set out in Table 1. The tentative redshifts are not used in any of the subsequent plots or analyses.

  figure373
Figure 2: Distribution of the galaxies with radial velocities. The Crux survey region is outlined. Solid circles indicate the positions of galaxies, in the Crux region, observed in the present work, and for which redshifts have been obtained. Open circles show the positions of galaxies for which redshifts are available from the literature

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Figure 3: Magnitude and major-axis diameter distribution of galaxies with radial velocities in the Crux search area. The lighter hatched areas mark galaxies observed at the SAAO, the darker hatched by others. The bottom panel shows the completeness in percent of the total number of galaxies found in the Crux Region (cf. Fig. 1 (click here))

Figure 2 (click here) shows the sky coverage of the galaxies with reliable redshifts, depicted by solid circles. The coverage can be seen to be reasonably uniform, on both the north and south sides of the galactic obscuration. By contrast, the data from Table 4 - galaxies with previously known redshifts as depicted by the open circles - is strongly concentrated north of the plane. This is due to the redshift surveys in that area that focussed on the Great Attractor (esp. Dressler 1991; Visvanathan & van den Bergh 1992).

Figure 3 (click here) presents a comparison of the magnitudes and major-axis distribution of the observed galaxies; it shows general similarity to the corresponding plot in Paper I. The sharp magnitude cut-off indicates the limiting performance of the 1.9 m telescope for galaxies fainter than (tex2html_wrap_inline1262).

These observations trace the bright end of the magnitude distribution of the 3760 galaxies in the Crux region very well. We are 70% complete for galaxies brighter than (tex2html_wrap_inline1408) and even 54% complete for galaxies brighter than (tex2html_wrap_inline1410). These numbers are comparable to the completeness figures in the Hydra-Antlia region. As before, a number of bright galaxies are missed by this survey. They are extended low surface brightness spiral galaxies. In the meantime, they have been observed with the Parkes 64-m telescope and will be reported on elsewhere.


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