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We present K-band number counts for the faint galaxies in the Calar Alto Deep Imaging Survey (CADIS). We covered 4 CADIS fields, a total area of 0.2deg^2, in the broad band filters B, R and K. We detect about 4000 galaxies in the K-band images, with a completeness limit of K=19.75mag, and derive the K-band galaxy number counts in the range of 14.25 < K < 19.75mag. This is the largest medium deep K-band survey to date in this magnitude range. The B- and R-band number counts are also derived, down to completeness limits of B=24.75mag and R=23.25mag. The K-selected galaxies in this magnitude range are of particular interest, since some medium deep near-infrared surveys have identified breaks of both the slope of the K-band number counts and the mean B-K color at K=17sim18mag. There is, however, a significant disagreement in the K-band number counts among the existing surveys. Our large near-infrared selected galaxy sample allows us to establish the presence of a clear break in the slope at K=17.0mag from dlogN/dm = 0.64 at brighter magnitudes to dlogN/dm = 0.36 at the fainter end. We construct no-evolution and passive evolution models, and find that the passive evolution model can simultaneously fit the B-, R- and K-band number counts well. The B-K colors show a clear trend to bluer colors for K > 18mag. We also find that most of the K=18-20mag galaxies have a B-K color bluer than the prediction of a no-evolution model for an L_* Sbc galaxy, implying either significant evolution, even for massive galaxies, or the existence of an extra population of small galaxies.
AstraLux is the Lucky Imaging camera for the Calar Alto 2.2-m telescope, based on an electron-multiplying high speed CCD. By selecting only the best 1-10% of several thousand short exposure frames, AstraLux provides nearly diffraction limited imaging
We present the results of a new, ultra-deep, near-infrared imaging survey executed with the Hawk-I imager at the ESO VLT, of which we make all the data public. This survey, named HUGS (Hawk-I UDS and GOODS Survey), provides deep, high-quality imaging
The Baryon Acoustic Oscillation (BAO) feature in the power spectrum of galaxies provides a standard ruler to measure the accelerated expansion of the Universe. To extract all available information about dark energy, it is necessary to measure a stand
AstraLux is a Lucky Imaging camera for the Calar Alto 2.2-m telescope, based on an electron-multiplying high speed CCD. By selecting only the best 1-10% of several thousand short exposure frames, AstraLux provides nearly diffraction limited imaging c
We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction.We summarize the survey goals and design, including sample selection and observational strategy.We also showc