On the quiescence of the Hubble flow in the vicinity of the Local Group

T. Ekholm; Yu. Baryshev; P. Teerikorpi; M. O. Hanski; G. Paturel

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On the quiescence of the Hubble flow in the vicinity of the Local Group

T. Ekholm·Yu. Baryshev·P. Teerikorpi·M. O. Hanski·G. Paturel

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Abstract

Cepheid distances of local galaxies (<7 Mpc) are used to study the very nearby velocity field, as pioneered by Sandage (Sandage 1986) who also pointed out its remarkable properties: linearity and quietness. The new data show that the velocity dispersion in the distance range as seen from the barycentre of the Local Group 1-8 Mpc is as low as 38 km/sec. The local rate of expansion coincides with the global Hubble constant. Down to 1.5 Mpc we cannot detect a deviation from the linear Hubble flow. This puts an upper limit for the mass of the Local Group, for a wide class of Friedman models, including those with the cosmological constant.

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T. Ekholm, Yu. Baryshev, P. Teerikorpi, M. O. Hanski, G. Paturel. 2001-03-06. On the quiescence of the Hubble flow in the vicinity of the Local Group. https://arxiv.org/abs/astro-ph/0103090

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