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Galaxies and Cosmology with DENIS

G. A. Mamon·M. Tricottet·W. Bonin·V. Banchet
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Abstract

The DENIS survey is currently imaging 21334 deg^2 of the mainly southern sky in the IJK and the observations are expected to go on until mid 2000. The expectations for extragalactic and cosmological research are outlined, including a quantitative assessment of the effects of recent star formation on the measured fluxes of galaxies. The galaxy extraction is much improved with the modeling of the PSF across the 12'x12' frames and the reliability of star/galaxy separation (currently based upon a combination of classical and neural-network based methods) is measured from visual inspection to be >90% at I = 16. The I band counts follow the high bright-end normalization and the J differential counts follow N(J) \simeq 11 \times dex [0.6 (J-14)] deg^{-2} mag^{-1} and are expected to be complete, reliable and photometrically accurate (Δm < 0.1) for J \leq 14.

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G. A. Mamon, M. Tricottet, W. Bonin, V. Banchet. 1997-11-24. Galaxies and Cosmology with DENIS. https://arxiv.org/abs/astro-ph/9711281

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