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arXiv · 1408.3416

Stellar mass functions of galaxies at 4<z<7 from an IRAC-selected sample in COSMOS/UltraVISTA: limits on the abundance of very massive galaxies

Mauro Stefanon·Danilo Marchesini·Adam Muzzin·Gabriel G. Brammer·James S. Dunlop·Marijin Franx·Johan P. U. Fynbo·Ivo Labbe·Bo Milvang-Jensen·Pieter G. van Dokkum
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Abstract

We build a Spitzer IRAC complete catalog of objects, obtained by complementing the $K_\mathrm{s}$-band selected UltraVISTA catalog with objects detected in IRAC only. With the aim of identifying massive (i.e., $\log(M_*/M_\odot)>11$) galaxies at $4 4$ galaxies with best fit masses $\log(M_*/M_\odot)>11$ by 83%, implying a rapid growth of very massive galaxies in the first 1.5 Gyr of cosmic history. From the stellar-mass complete sample, we identify one candidate of a very massive ($\log(M_*/M_\odot)\sim11.5$), quiescent galaxy at $z\sim5.4$, with MIPS $24μ$m detection suggesting the presence of a powerful obscured AGN.

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Mauro Stefanon, Danilo Marchesini, Adam Muzzin, Gabriel G. Brammer, James S. Dunlop, Marijin Franx, Johan P. U. Fynbo, Ivo Labbe, Bo Milvang-Jensen, Pieter G. van Dokkum. 2015-03-30. Stellar mass functions of galaxies at 4<z<7 from an IRAC-selected sample in COSMOS/UltraVISTA: limits on the abundance of very massive galaxies. https://doi.org/10.1088/0004-637x%2F803%2F1%2F11

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