A&A 375, 338-343 (2001)
The velocity field of collapsing spherical structures
Limitations of the spherical infall model in mass estimationN. Hiotelis
Lyceum of Naxos, Chora of Naxos, Naxos 84300, Greece
(Received 15 January 2001 / Accepted 28 May 2001 )
We assume that the amplitude of the caustics in redshift space is a sum of two components: the first one can be predicted by the spherical infall model with no random motion, and the second is due to the random motion distribution. Smooth model curves are used to estimate the maximum values of the first component for the Coma cluster. Then, an approximation of the radial component of the infall velocity -based on the above curves -is derived and a mass profile of the cluster is calculated. This mass profile, that is an upper limit for the spherical infall model, combined with estimations given by other authors provides an approximation of a lower limit for the mass of the system.
Key words: galaxies: clusters: general -- galaxies: clusters: individual: coma cluster -- cosmology: large-scale structure of Universe
© ESO 2001