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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.
In order to map the galaxy density field in the local universe, we select the Nearby Optical Galaxy (NOG) sample, which is a distance-limited (cz < 6000 km/s) and magnitude--limited (B < 14 mag) sample of 7076 optical galaxies which covers 2/3 (8.29
In order to map the galaxy density field on small scales in the local universe, we use the Nearby Optical Galaxy (NOG) sample, which is currently one of the largest, nearly complete, magnitude-limited ($Bleq$ 14 mag), all-sky sample of nearby optical
It is well known gravitational lensing, mainly via magnification bias, modifies the observed galaxy/quasar clustering. Such discussions have largely focused on the 2D angular correlation. Here and in a companion paper (Paper II) we explore how magnif
Galaxy formation inside dark matter halos, as well as the halo formation itself, can be affected by large-scale environments. Evaluating the imprints of environmental effects on galaxy clustering is crucial for precise cosmological constraints with d
We develop a maximum likelihood based method of reconstructing band powers of the density and velocity power spectra at each wavenumber bins from the measured clustering features of galaxies in redshift space, including marginalization over uncertain