The Journal of Astronomical Data


Contents and Abstracts of Volume 2


[1] B, V, R, I, H and K images of 86 face-on spiral galaxies / Roelof S. de Jong*
[ca. 620 Mbyte, FITS] / *University of Durham (UK) / Kapteyn Institute, Groningen
abstract


[JAD 2, 1]
B, V, R, I, H and K images of 86 face-on spiral galaxies

FITS images in the B, V, R, I, H and K passbands are presented of a sample of 86 face-on spiral galaxies. The galaxies were selected from the UGC to have a diameter of at least 2" and a minor over major axis ratio larger than 0.625. The selected galaxies have an absolute Galactic latitude |b|>25 deg, to minimize the effect of Galactic extinction and foreground stars. Nearly all BVRI data were obtained with the 1m Jacobus Kapteyn Telescope at La Palma and the H and K data were obtained at the 3.8m UK Infra-Red Telescope at Hawaii. The field of view of the telescope/camera combinations were often smaller than the observed galaxies, therefore driftscanning and mosaicing techniques were employed to image at least along the major axis of the galaxies. Most images were obtained during photometric nights and calibrated using standard stars. A small fraction of the images was calibrated from literature aperture photometry.

The azimuthally averaged radial luminosity profiles derived from these galaxy images are also made available in machine readable format, as well as the results of the bulge/disk decompositions.

A great deal about galaxy evolution can be learned by studying their broadband properties. Broadband observations give an immediate impression of the spectral energy distribution and thereby information on stellar and dust content. Even though integrated magnitudes of galaxies can be used to study global properties of galaxies, even more can be learned from examining the detailed distribution of their light and colors. The star formation history in galaxies seems to be related to their surface density properties, and therefore it is imperative to have a statistical knowledge of surface brightness distributions in galaxies to understand galaxy evolution.

The image data set presented here was collected to study the surface brightness distribution of spiral galaxies. Of special interest was the question whether disks in spiral galaxies have a preferred central surface brightness value as proposed by Freeman. The observations were made in such a way that they were suitable to study this central surface brightness effect.


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