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arXiv · 0906.3111

Is the misalignment of the Local Group velocity and the 2MASS Redshift Survey dipole typical in a LambdaCDM model?

Pirin Erdogdu·Ofer Lahav
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Abstract

We predict the acceleration of the Local Group generated by the 2MASS Redshift Survey within the framework of LambdaCDM and the halo model of galaxies. We show that as the galaxy fluctuations derived from the halo model have more power on small scales compared with the mass fluctuations, the misalignment angle between the CMB velocity vector and the 2MRS dipole is in reasonable agreement with the observed 21 degrees. This statistical analysis suggests that it is not necessary to invoke a hypothetical nearby galaxy or a distant cluster to explain this misalignment.

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Pirin Erdogdu, Ofer Lahav. 2009-08-04. Is the misalignment of the Local Group velocity and the 2MASS Redshift Survey dipole typical in a LambdaCDM model?. https://doi.org/10.1103/physrevd.80.043005

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