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Velocity Fields from IRAS-PSCz survey

E. Branchini·C. S. Frenk L. Teodoro·I. Schmoldt·G. Efstathiou·W. Saunders·S. D. M. White·M. Rowan-Robinson·W. Sutherland·H. Tadros·S. Maddox·S. Oliver·O. Keeble
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Abstract

We present a self-consistent nonparametric model of the cosmic velocity field based on the spatial distribution of IRAS galaxies in the recently completed all-sky PSC$z$ redshift survey. The most streaking feature of the PSCz model velocity field is a coherent large-scale streaming motion along the Perseus Pisces, Local Supercluster, Great Attractor and Shapley Concentration baseline, with no evidence for a backinfall into the Great Attractor region. A likelihood analysis has been performed to measure $β$. We have obtained $β=0.6^{+0.22}_{-0.15}$ (1-$σ$), in agreement with other recent determinations.

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E. Branchini, C. S. Frenk L. Teodoro, I. Schmoldt, G. Efstathiou, W. Saunders, S. D. M. White, M. Rowan-Robinson, W. Sutherland, H. Tadros, S. Maddox, S. Oliver, O. Keeble. 1998-10-07. Velocity Fields from IRAS-PSCz survey. https://arxiv.org/abs/astro-ph/9810106

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