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APPENDIX A. Table of Additional Bright Galaxies

The following tabulation contains 822 galaxies not in the SA but known to be brighter than B ~ 13m.4. Although the available information on the magnitudes of some entries is still of low quality, the tabulation provides a search list for use in any future attempt to compile a more complete catalog.

The list itself has no claim to completeness. The inclusion of a galaxy depends entirely on the availability of a magnitude value from some source. Most are drawn from the Zwicky catalog, which is limited to delta > -3°. For this reason, the data for the northern hemisphere are much more complete than for the southern.

The available magnitudes are not on a uniform system. The dwarf galaxies whose magnitudes by Fisher and Tully (1975) cannot be transformed into the BT system are listed separately at Appendix B. All other magnitudes either are published in the BT system or have been reduced to it, as explained in the key to the sources in the footnote ending Appendix A. The important exceptions are the Zwicky magnitudes. These were transformed into the BT system in the following way:

The BT magnitudes between 12m.5 and 14m.5 in the RC2 (de Vaucouleurs et al., 1977) that are not contained in the SA were compared with the Zwicky magnitudes. The exclusion of the SA galaxies is necessary because Zwicky used the SA magnitudes as one set of data for his adopted system. With this exclusion, however, the overlap between the two catalogs is small, and we could detect no significant magnitude equation as a function of galaxy type or apparent magnitude diameter. But there is a well-determined zero point correction, which varies for the different volumes of the Zwicky catalog as follows:

Zwicky BT - m
Volume (Zwicky) number sigma(m) adopted

I -0.40 ± 0.03 49 0.23 -0.4
II -0.39 ± 0.05 47 0.31 -0.4
III -0.30 ± 0.06 26 0.32 -0.3
IV -0.18 ± 0.03 28 0.68 -0.2
V -0.31 ± 0.08 37 0.48 -0.3
VI -0.33 ± 0.07 37 0.42 -0.3

These corrections have been applied in the main table of this Appendix.

de Vaucouleurs and Pence (1979) have reduced a set of Zwicky magnitudes for galaxies in the Virgo region into the BT system. They employed an elaborate transformation equation determined from a considerable number of local standard galaxies. Because of the obvious variations of the magnitude systems of the different volumes of the Zwicky catalog, it would not be justified to use their transformation for all Zwicky magnitudes. Hence, we have applied only the zero point corrections as given above. A comparison of the 33 galaxies which de Vaucouleurs and Pence reduced to the BT system with our values shows that B (de Vaucouleurs and Pence) -B (here) = +0m.12 ± 0m.05, with a scatter of sigma(B) = 0m.28. The external errors may of course be larger, but because photoelectric checks of Zwicky magnitudes also show reasonably small error similar to our values, the converted Zwicky magnitudes in the following list should be useful for future work.

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