SIMBAD references

We present deep infrared K-band surface photometry for a diameter-limited sample of normal Sb and Sc galaxies. In addition, surface brightness, optical and optical-infrared colors and isophote-shapes have been obtained from the ESO-LV B and R photographic images of these galaxies. For each galaxy we present global photometric parameters, as well as individual radial surface brightness and color profiles. Our analysis includes the fitting of ellipses in the three bands, bulge-disk decompositions, and the derivation of growth curves in elliptical apertures. The main conclusion of the paper is that these galaxies exhibit very large color gradients - B and K scale length ratios vary between 1.2 and 2.0 and increase with axis ratio. The large magnitude of these gradients suggest that they are not due to stellar population differences, but are primarily due to extinction by dust in the B-band. We also find that the range of central surface brightnesses in the K-band is considerably larger than in B, showing that the stellar properties are better studied in K. A more detailed evaluation of the results, specifically with regard to the spatial distribution of both the dust and the stars in Sb and Sc galaxies, will be presented in an accompanying paper (Peletier et al. 1994, Paper II).