Density and Velocity Fields from the PSCz Survey

Will Saunders; Enzo Branchini; Luis Teodoro; Alan Heavens; Andy Taylor; Helen Valentine; Kenton D'Mellow; Seb Oliver; Oliver Keeble; Michael Rowan-Robinson; Jacob Sharpe; Steve Maddox; Richard McMahon; George Efstathiou; Will Sutherland; Helen Tadros; Bill Ballinger; Inga Schmolt; Carlos Frenk; Simon White

arXiv · astro-ph/9909190

Density and Velocity Fields from the PSCz Survey

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Abstract

We present the results for the predicted density and peculiar velocity fields and the dipole from the PSCz survey of 15,000 IRAS galaxies over 84% of the sky. We find a significant component to the dipole arising between 6000 and 15,000 km/s, but no significant component from greater distances. The misalignment with the CMB is 20 degrees. The most remarkable feature of the PSCz model velocity field is a coherent large-scale flow along the baseline connecting Perseus-Pisces, the Local Supercluster, Great Attractor and the Shapley Concentration. We have measured the parameter beta using the amplitude of the dipole, bulk flow and point by point comparisons between the individual velocities of galaxies in the MarkIII and SFI datasets, and the large-scale clustering distortion in redshift space.All our results are consistent with beta = 0.6 +- 0.1.

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Will Saunders, Enzo Branchini, Luis Teodoro, Alan Heavens, Andy Taylor, Helen Valentine, Kenton D'Mellow, Seb Oliver, Oliver Keeble, Michael Rowan-Robinson, Jacob Sharpe, Steve Maddox, Richard McMahon, George Efstathiou, Will Sutherland, Helen Tadros, Bill Ballinger, Inga Schmolt, Carlos Frenk, Simon White. 1999-09-10. Density and Velocity Fields from the PSCz Survey. https://arxiv.org/abs/astro-ph/9909190

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