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arXiv · 1910.07544

Massive and old quiescent galaxies at high redshift

Giacomo Girelli·Micol Bolzonella·Andrea Cimatti
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Abstract

Massive quiescent galaxies at high redshift can shed light on the processes of galaxy mass assembly and quenching of the star formation at early epochs. We present observer-frame color-color diagrams designed to identify candidate quiescent galaxies from z=2.5 up to the highest redshifts, that can be then be selected for spectroscopic follow-up observations. The application to the COSMOS2015 catalog shows that, after refining the selection with SED fitting, the number of massive old quiescent galaxies exceeds the forecast of state-of-the-art semi-analytic models, pointing out the need of an improvement of the implemented quenching mechanisms at high redshifts.

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Giacomo Girelli, Micol Bolzonella, Andrea Cimatti. 2019-10-16. Massive and old quiescent galaxies at high redshift. https://doi.org/10.1051/0004-6361%2F201834547

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