The Munich Near-Infrared Cluster Survey - I. Field selection, object extraction, and photometry


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The Munich Near-IR Cluster Survey (MUNICS) is a wide-area, medium-deep, photometric survey selected in the K band. It covers an area of roughly one square degree in the K and J near-IR pass-bands. The survey area consists of 16 6 x 6 fields targeted at QSOs with redshifts 0.5 < z < 2 and 7 28 x 13 stripes targeted at `random high Galactic latitude fields. Ten of the QSO fields were additionally imaged in R and I, and 0.6 square degrees of the randomly selected fields were also imaged in the V, R, and I bands. The resulting object catalogues were strictly selected in K, having a limiting magnitude (50 per cent completeness) of K ~ 19.5 mag and J ~ 21 mag, sufficiently deep to detect passively evolving systems up to a redshift of z ~ 1.5 and luminosity of 0.5 L*. The optical data reach a depth of roughly R ~ 23.5 mag. The projects main scientific aims are the identification of galaxy clusters at redshifts around unity and the selection of a large sample of field early-type galaxies at 0 < z < 1.5 for evolutionary studies. In this paper - the first in a series - we describe the surveys concept, the selection of the survey fields, the near-IR and optical imaging and data reduction, object extraction, and the construction of photometric catalogues. Finally, we show the J-K vs. K colour-magnitude diagramme and the R-J vs. J-K, V-I vs. J-K, and V-I vs. V-R colour-colour diagrammes for MUNICS objects, together with stellar population-synthesis models for different star-formation histories, and conclude that the data set presented is suitable for extracting a catalogue of massive field galaxies in the redshift range 0.5 < z < 1.5 for evolutionary studies and follow-up observations.

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