The VIRMOS deep imaging survey. III. ESO/WFI deep U-band imaging of the 0226-04 deep field

International audienceIn this paper we describe the U-band imaging of the F02 deep field, one of the fields in the VIRMOS Deep Imaging Survey. The observations were done at the ESO/MPG 2.2 m telescope at La Silla (Chile) using the 8k × 8k Wide-Field Imager (WFI). The field is centered at alpha(J2000)=02h26m00s and delta(J2000)=-04°30'00", the total covered area is 0.9 °2 and the limiting magnitude (50% completeness) is U_AB ˜ 25.4 mag. Reduction steps, including astrometry, photometry and catalogue extraction, are first discussed. The achieved astrometric accuracy (rms) is ˜0.2 arcsec with reference to the I-band catalog and ˜0.07 arcsec internally (estimated from overlapping sources in different exposures). The photometric accuracy including uncertainties from photometric calibration, i