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arXiv · astro-ph/0311490

The radio galaxy K-z relation: the 10^12 Msol mass limit; masses of galaxies from the L_K luminosity, up to z >4

Abstract

The narrow K-z relation of powerful radio galaxies in the Hubble K diagram is often attributed to the stellar populations of massive elliptical galaxies. Extended over a large range of redshifts (0 4 implies that massive clouds were already formed at early epochs. We also find that the M_(bar,max) limit is similar to the critical mass M_crit of a self-gravitating cloud regulated by cooling (Rees & Ostriker, 1977; Silk, 1977). Moreover, the critical size r_crit = 75 Kpc is remarkably close to the typical diameter of Ly_alpha haloes surrounding distant radio galaxies. This confirms the validity of the method of baryonic mass determination based on the K-band luminosity. A puzzling question that remains to be answered is the short time-scale of mass-accumulation required to form such massive galaxies at z=4. We discuss the dispersion of the K-z relation and the link between the active nucleus and a large stellar mass.

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B. Rocca-Volmerange, D. Le Borgne, C. De Breuck, M. Fioc, E. Moy. 2003-11-20. The radio galaxy K-z relation: the 10^12 Msol mass limit; masses of galaxies from the L_K luminosity, up to z >4. https://doi.org/10.1051/0004-6361%3A20031717

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