* Astronomy

Title: Two new confirmed massive relic galaxies: red nuggets in the present-day Universe
Author: Anna Ferré-Mateu, Ignacio Trujillo, Ignacio Martín-Navarro, Alexandre Vazdekis, Mar Mezcua, Marc Balcells, Lilian Domínguez

We confirm two new local massive relic galaxies, i.e. untouched survivors of the early universe massive population: Mrk1216 and PGC032873. Both show early and peaked formation events within very short timescales (2 massive population, setting them apart of the typical z~0 massive early-type galaxies. We find that there seems to exist a "degree of relic" that is related on how far into the path to become one of these typical z~0 massive galaxies the compact relic has undergone. This path is partly dictated by the environment the galaxy lives in. For galaxies in rich environments, such as the previously reported relic galaxy NGC1277, the most extreme properties (e.g. sizes, short formation timescales, larger super-massive black holes) are expected, while lower density environments will have galaxies with delayed and/or extended star formations, slightly larger sizes and not that extreme black hole masses. The confirmation of 3 relic galaxies up to a distance of 106Mpc implies a lower limit in the number density of these red nuggets in the local universe of 6x10^{-7} Mpc^{3}, which is within the theoretical expectations.

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