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We investigate the causes of the different shape of the $K$-band number counts when compared to other bands, analyzing in detail the presence of a change in the slope around $Ksim17.5$. We present a near-infrared imaging survey, conducted at the 3.5m telescope of the Calar Alto Spanish-German Astronomical Center (CAHA), covering two separated fields centered on the HFDN and the Groth field, with a total combined area of $sim0.27$deg$^{2}$ to a depth of $Ksim19$ ($3sigma$,Vega). We derive luminosity functions from the observed $K$-band in the redshift range [0.25-1.25], that are combined with data from the references in multiple bands and redshifts, to build up the $K$-band number count distribution. We find that the overall shape of the number counts can be grouped into three regimes: the classic Euclidean slope regime ($dlog N/dmsim0.6$) at bright magnitudes; a transition regime at intermediate magnitudes, dominated by $M^{ast}$ galaxies at the redshift that maximizes the product $phi^{ast}frac{dV_{c}}{dOmega}$; and an $alpha$ dominated regime at faint magnitudes, where the slope asymptotically approaches -0.4($alpha$+1) controlled by post-$M^{ast}$ galaxies. The slope of the $K$-band number counts presents an averaged decrement of $sim50%$ in the range $15.5<K<18.5$ ($dlog N/dmsim0.6-0.30$). The rate of change in the slope is highly sensitive to cosmic variance effects. The decreasing trend is the consequence of a prominent decrease of the characteristic density $phi^{ast}_{K,obs}$ ($sim60%$ from $z=0.5$ to $z=1.5$) and an almost flat evolution of $M^{ast}_{K,obs}$ (1$sigma$ compatible with $M^{ast}_{K,obs}=-22.89pm0.25$ in the same redshift range).
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
Aims. The Herschel-ATLAS survey (H-ATLAS) will be the largest area survey to be undertaken by the Herschel Space Observatory. It will cover 550 sq. deg. of extragalactic sky at wavelengths of 100, 160, 250, 350 and 500 microns when completed, reachin
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
We present the maps, source catalogue and number counts of the largest, most complete and unbiased extragalactic submillimetre survey ever undertaken: the 850-micron SCUBA HAlf Degree Extragalactic Survey (SHADES). Using the Submillimetre Common-User
We present the 3-8 keV and 8-24 keV number counts of active galactic nuclei (AGN) identified in the NuSTAR extragalactic surveys. NuSTAR has now resolved 33-39% of the X-ray background in the 8-24 keV band, directly identifying AGN with obscuring col