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arXiv · 1002.2085

The observed infall of galaxies towards the Virgo cluster

I. D. Karachentsev·O. G. Nasonova
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Abstract

We examine the velocity field of galaxies around the Virgo cluster induced by its overdensity. A sample of 1792 galaxies with distances from the Tip of the Red Giant Branch, the Cepheid luminosity, the SNIa luminosity, the surface brightness fluctuation method, and the Tully-Fisher relation has been used to study the velocity-distance relation in the Virgocentric coordinates. Attention was paid to some observational biases affected the Hubble flow around Virgo. We estimate the radius of the zero-velocity surface for the Virgo cluster to be within (5.0 - 7.5) Mpc corresponding to (17 - 26)^\circ at the mean cluster distance of 17.0 Mpc. In the case of spherical symmetry with cosmological parameter Ω_m=0.24 and the age of the Universe T_0= 13.7 Gyr, it yields the total mass of the Virgo cluster to be within M_T=(2.7 - 8.9) * 10^{14} M_\sun in reasonable agreement with the existing virial mass estimates for the cluster.

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I. D. Karachentsev, O. G. Nasonova. 2010-02-11. The observed infall of galaxies towards the Virgo cluster. https://doi.org/10.1111/j.1365-2966.2010.16501.x

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