Measuring the gravitational redshift in dark matter haloes

MARIANO JAVIER DE LEON DOMINGUEZ ROMERO; DIEGO GARCIA LAMBAS; MURIEL HERNAN

Carlos Paz, Córdoba

Congreso; 97ª Reunión Nacional de la Asociación Física Argentina; 2012

FaMAF

We introduce a new method for the identification of galaxy systems in redshift surveys based on the halo model. This method is a modified version of the K-means identification algorithm developed by Yang et al. (2005). We have calibrated and tested our algorithms using mock catalogs generated using the Millennium simulations (Springel et al. 2005) and applied them to the NYU-DR7 galaxy catalog (based on the SDSS datasets). Using this local sample of groups and clusters of galaxies we have measured the effect of gravitational redshift produced by their host dark matter haloes. Our results shows radial velocity decrements consistent with general relativity predictions and previous measurements by Wojtak et al. (2011) in cluster of galaxies.