SIMBAD references

Pratton et al. (1997ApJ...479L..15P) showed that the velocity field around clusters could generate an apparent distortion that appears as tangential structures or radial filaments. In the present paper we determine the parameters of the Peebles' model (1976ApJ...205..318P) describing infall of galaxies onto clusters with the aim of testing quantitatively the amplitude of this distortion. The distances are determined from the concept of sosie galaxies (Paturel, 1984ApJ...282..382P) using 21 calibrators for which the distances were recently calculated from two independent Cepheid calibrations. We use both B and I-band magnitudes. The Spaenhauer diagram method is used to correct for the Malmquist bias. We give the equations for the construction of this diagram. We analyze the apparent Hubble constant in different regions around Virgo and obtain simultaneously the Local Group infall and the unperturbed Hubble constant. We found: V_LG–infall=208±9km/s; logH=1.82±0.04 these quantities form an accurate and coherent system.