I. Near-infrared imaging
نویسندگان
چکیده
As a prerequisite for cosmological studies using adaptive optics techniques, we have begun to identify and characterize faint sources in the vicinity of bright stars at high Galactic latitudes. The initial phase of this work has been a program of Ks imaging conducted with SOFI at the ESO NTT. From observations of 42 southern fields evenly divided between the spring and autumn skies, we have identified 391 additional stars and 1589 galaxies lying at separations ∆θ ≤ 60′′ from candidate guide stars in the magnitude range 9.0 ≤ R ≤ 12.4. When analyzed as a “discrete deep field” with 131 arcmin area, our dataset gives galaxy number counts that agree with those derived previously over the range 16 ≤ Ks < 20.5. This consistency indicates that in the aggregate, our fields should be suitable for future statistical studies. We provide our source catalogue as a resource for users of large telescopes in the southern hemisphere.
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