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The NOG Sample: Galaxy Systems and 3D Real-Space Galaxy Density

C. Marinoni·G. Giuricin·L. Ceriani·A. Pisani
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Abstract

We discuss the 3D real-space reconstruction of the optical galaxy density field in the local Universe as derived from the galaxies of the Nearby Optical Galaxy (NOG) sample. NOG is a distance-limited (cz_{LG} < 6000 km/s) and magnitude--limited (B<14 mag) sample of 7076 optical galaxies which covers 2/3 (8.29 sr) of the sky (|b|>20). We have replaced ``true distances'' measurements for all the objects in order to correct for redshif distortions. Using homogenized photometric information for the whole sample, NOG is meant to be an approximation to a homogeneous all-sky 3D optically selected and statistically well-controlled galaxy sample that probes in great detail volumes of cosmological interest. Our goal is to construct a reliable, robust and unbiased field of density contrasts covering interesting regions of galaxy and mass overdensities of the local universe.

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C. Marinoni, G. Giuricin, L. Ceriani, A. Pisani. 1999-09-27. The NOG Sample: Galaxy Systems and 3D Real-Space Galaxy Density. https://arxiv.org/abs/astro-ph/9909444

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