The SCUBA Half Degree Extragalactic Survey (SHADES) – IX. The environment, mass and redshift dependence of star formation

摘要: We present a comparison between the SCUBA (Submillimetre Common User Bolometer Array) Half Degree Extragalactic Survey (SHADES) at 450 and 850 ?m in Lockman Hole East with deep Spitzer Space Telescope survey 3.6–24 conducted guaranteed time. Using stacking analyses we demonstrate striking correspondence galaxies contributing submm extragalactic background light, those likely to dominate backgrounds wavelengths. combination BRIzK plus photometric redshifts, show that least third of Spitzer-identified 1 < z 1.5 appear reside overdensities when density field is smoothed 0.5–2 Mpc comoving diameters, supporting high-redshift reversal local star formation–galaxy relation. derive dust-shrouded cosmic formation history as function assembled stellar masses. For model masses <1011 M?, this peaks lower redshifts than ostensible z~ 2.2 maximum for point sources, adding growing consensus 'downsizing' formation. Our surveys are also consistent mass assembly. Both mean rates ?dM*/dt? specific ?(1/M*) d M*/d t? disagreement some semi-analytic predictions from Millenium Simulation. The discrepancy could either be resolved top-heavy initial function, or significant component flux heated by interstellar radiation field.