4.3. Treatment of Virgo
To simplify the analysis, we have taken
the small-scale velocity
noise, v,
to be independent of position. Clearly, this assumption must fail in the
immediate vicinity of a rich cluster. The Virgo Cluster is the only rich
cluster within 3000 km s-1. Thus, we must artificially
"cool down" the
galaxies near Virgo. We do so as follows: if a galaxy lies within
10° of the Virgo core (taken to be l =
283.78°, b = 74.49°)
on the sky, within 1500 km s-1 of its mean Local Group redshift
(taken to be 1035.1 km s-1, following
Huchra 1985),
and has a raw TF distance
from Willick et
al. (1997) between 800 and 2100 km
s-1, its Local Group redshift is set to the mean Virgo value.
Twenty objects used in the VELMOD analysis meet these criteria. We
similarly collapsed mock Mark III objects associated with the Virgo Cluster
in the mock catalogs.