Evolution of Large Scale Structure { Garching , August 1998 THE EFAR PECULIAR VELOCITY
نویسندگان
چکیده
The EFAR collaboration has measured the structural parameters (half-luminosity radii, total magnitudes, central velocity dispersions and Mg indexes) of galaxies in 84 clusters of the Hercules-Corona Borealis and Pisces-Cetus regions, with redshifts 6000< cz <15000. Analysing this database by means of a Maximum Likelihood algorithm, the Fundamental Plane relation derived is in agreement with existing determinations, and used to determine the peculiar velocities (PV) of the clusters. We nd that the mean peculiar velocities in the two regions are small and compatible with zero motions. We rule out at the 3 level the large bulk ow motion measured by Lauer and Postman (1994). We suggest that distances derived using cD galaxies might be biased due to stellar population eeects.
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