Abstract
Using a sample of 25683 star-forming and 2821 passive galaxies at $z\sim2$,
selected in the COSMOS field following the BzK color criterion, we study the
hosting halo mass and environment of galaxies as a function of their physical
properties. Spitzer and Herschel provide accurate SFR estimates for starburst
galaxies. We measure the auto- and cross-correlation functions of various
galaxy sub-samples and infer the properties of their hosting halos using both
an HOD model and the linear bias at large scale. We find that passive and
star-forming galaxies obey a similarly rising relation between the halo and
stellar mass. The mean host halo mass of star forming galaxies increases with
the star formation rate between 30 and 200 M$_ødot$.yr$^-1$, but flattens
for higher values, except if we select only main-sequence galaxies. This
reflects the expected transition from a regime of secular co-evolution of the
halos and the galaxies to a regime of episodic starburst. We find similar large
scale biases for main-sequence, passive, and starburst galaxies at equal
stellar mass, suggesting that these populations live in halos of the same mass.
We detect an excess of clustering on small scales for passive galaxies and
showed, by measuring the large-scale bias of close pairs, that this excess is
caused by a small fraction ($\sim16%$) of passive galaxies being hosted by
massive halos ($3 10^13$ M$_ødot$) as satellites. Finally,
extrapolating the growth of halos hosting the z$\sim$2 population, we show that
M$_10^10$ M$_ødot$ galaxies at z$\sim$2 will evolve, on average,
into massive (M$_10^11$ M$_ødot$), field galaxies in the local
Universe and M$_10^11$ M$_ødot$ galaxies at z=2 into local,
massive, group galaxies. The most massive main-sequence galaxies and close
pairs of massive, passive galaxies end up in today's clusters.
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