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The Galaxy Group/Cosmology Connections

Gary A. Mamon
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Abstract

\def\spose#1{\hbox to 0pt{#1\hss}} \def\lta{\mathrel{\spose{\lower 3pt\hbox{$\mathchar"218$}} \raise 2.0pt\hbox{$\mathchar"13C$}}} Groups of galaxies are highly linked to cosmology: 1) groups are tidally destroyed by the tidal field of the cluster they fall into; 2) spherical infall leads to the young cosmo-dynamical state of loose groups, a fundamental surface for groups, $Ω_0 \simeq 0.3$, and the mixed nature of compact groups (virialized groups, groups at full collapse, and chance alignments within collapsing loose groups, for decreasing compact group velocity dispersion) ; 3) X-ray analyses lead to $Ω_0 \lta 0.5$.

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Gary A. Mamon. 1994-06-14. The Galaxy Group/Cosmology Connections. https://arxiv.org/abs/astro-ph/9406043

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