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An image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
| Spectroscopy of Zwicky galaxies identified with B3 radiosources
Results are presented of long-slit CCD spectroscopy of 33 Zwickygalaxies identified in the B3 Survey as radiosources, includinginformation on morphological classification, photographic magnitude,line identification, measured wavelength, adopted rest wavelength,redshift computed for the line, and average redshift and rms. In thissample, 24 galaxies showed emission (and often absorption) lines, while9 galaxies showed only absorption lines. Nine of the 14 galaxiesclassified as E/SO showed the forbidden N II emission line at an EW(lim)= 1.5 A. The rest were classified as Spirals, and, out of 19 of thesegalaxies, 15 showed the forbidden N II emission line. No significantdifferences were found between the percentage of galaxies with emissionlines in this sample and the samples of optically selected galaxies ofsimilar equivalent width limit.
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