Ryan C. Hickox, J. L. Wardlow, Ian Smail, A. D. Myers, D. M. Alexander, A. M. Swinbank, A. L. R. Danielson, J. P. Stott, S. C. Chapman, K. E. K. Coppin, J. S. Dunlop, E. Gawiser, D. Lutz, P. van der Werf, A. Weiss
We present a measurement of the spatial clustering of submillimetre galaxies
(SMGs) at z = 1-3. Using data from the 870 micron LESS survey, we employ a
novel technique to measure the cross-correlation between SMGs and galaxies,
accounting for the full probability distributions for photometric redshifts of
the galaxies. From the observed projected two-point cross-correlation function
we derive the linear bias and characteristic dark matter (DM) halo masses for
the SMGs. We detect clustering in the cross-correlation between SMGs and
galaxies at the > 4 sigma level. For the SMG autocorrelation we obtain r_0 =
7.7 (+1.8,-2.3) h^-1 Mpc, and derive a corresponding DM halo mass of log(M_halo
[h^-1 M_sun]) = 12.8 (+0.3,-0.5). Based on the evolution of DM haloes derived
from simulations, we show that that the z = 0 descendants of SMGs are typically
massive (~2-3 L*) elliptical galaxies residing in moderate- to high-mass groups
(log(M_halo [h^-1 M_sun]) = 13.3 (+0.3,-0.5). From the observed clustering we
estimate an SMG lifetime of ~100 Myr, consistent with lifetimes derived from
gas consumption times and star-formation timescales, although with considerable
uncertainties. The clustering of SMGs at z ~ 2 is consistent with measurements
for optically-selected quasi-stellar objects (QSOs), supporting evolutionary
scenarios linking starbursts and QSOs. Given that SMGs reside in haloes of
characteristic mass ~ 6 x 10^12 h^-1 M_sun, we demonstrate that the redshift
distribution of SMGs can be described remarkably well by the combination of two
effects: the cosmological growth of structure and the evolution of the
molecular gas fraction in galaxies. We conclude that the powerful starbursts in
SMGs likely represent a short-lived but universal phase in massive galaxy
evolution, associated with the transition between cold gas-rich, star-forming
galaxies and passively evolving systems. [Abridged]
View original:
http://arxiv.org/abs/1112.0321
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