DEEP R-BAND PHOTOMETRY FOR NORTHERN SPIRAL GALAXIES

We present r-band surface photometry for 349 northern Sb-Sc UGC galaxi es, from a total of 627 CCD images. For each galaxy, we present surfac e brightness profiles, isophotal and total magnitudes, isophotal radii , and structural parameters from exponential fits to the disk. One hun dred ninety-five galaxies have been observed more than once. All night s with a photometric transformation scatter greater than 0.022 mag wer e rejected. Sky errors are investigated carefully and yield profiles t hat are reliable down to 26 r mag arcsec(-2). Deep isophotal magnitude s are as accurate as +/-0.019, and extrapolated magnitudes are interna lly consistent to within 0.020. We compare visual (UGC) and CCD isopho tal diameters and show that axial ratio must be included as a third pa rameter. Comparison with the r-band CCD photometry of Kent and Willick , and accounting for sky errors, suggest typical errors for total magn itudes of +/-0.08. Our data are also shown to be zero-pointed on the s ame Gunn r system as that of Rent and Willick. Ellipticity measurement s agree very well except for progressively face-on galaxies where spir al structure is more conspicuous. The ellipticity internal error is le ss than 0.02, or about 3 degrees for inclinations. Our internal extinc tion correction implies that disks are semitransparent in their outer parts. We caution that comparison of central surface brightnesses and scale lengths is complicated by the subjective nature of their measure ment; extreme care must be applied when using such quantities. We meas ure an apparent Freeman law of [mu(0,c)] = 20.08 +/- 0.55 r mag arcsec (-2). This magnitude-limited sample was originally derived for studies of large-scale motions in the local universe. The deep CCD photometry is also ideally suited for matching spectroscopic studies, mass model ing, galaxy structural analysis, etc.