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KLUN+ peculiar velocity survey

M O Hanski
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Abstract

The enhanced Kinematics of the Local Universe (KLUN+) galaxy sample is a collection of galaxies suitable for Tully-Fisher (TF) or Faber-Jackson (FJ) distance estimation. Here we extract a subsample of 6229 KLUN+ galaxies closer than 80 Mpc/h, and calculate their distances and peculiar velocities with the Iterative Normalized Distance method. Within this method we can derive an analytical formula, independent from the density inhomogeneities, for correcting the selection biases. The radial peculiar velocities can then be derived from the redshifts and the corrected distances. The velocities are smoothed, and the smoothed velocity field is used as a correction term at the next derivation of normalized distances. This iterative procedure is repeated until converging values are reached. Here we present the resulting map of the radial peculiar velocity field at the < 80 Mpc/h environment. The infall patterns towards the main galaxy clusters are clearly visible. The color version of the map, other figures, and animations are provided on the project web site.

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M O Hanski. 2003-09-30. KLUN+ peculiar velocity survey. https://arxiv.org/abs/astro-ph/0309821

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