U-band photometry of 17 WINGS clusters

Since not all the observations were taken in good transparency conditions, the photometric calibration was partly obtained by relying on the SDSS and WINGS-OPT photometry for the U- and optical bands, respectively. We provide U-band (also B- and V-band, where possible) total magnitudes of stars and galaxies in the fields of clusters. For galaxies only, the catalogs also provide geometrical parameters and carefully centered aperture magnitudes.

The internal consistency of magnitudes was checked for clusters imaged with different cameras, while the external photometric consistency was obtained by comparison with the WINGS-OPT and SDSS surveys. The photometric catalogs presented here add the U-band information to the WINGS database for extending the spectral energy distribution (SED) of the galaxies, in particular in the ultraviolet (UV) wavelengths which are fundamental for deriving the star formation rate (SFR) properties.