부산대학교 도서관

We present a comparison between the SCUBA Half Degree Extragalactic Survey (SHADES) at 450 and 850 microns in the Lockman Hole East with a deep Spitzer Space Telescope survey at 3.6-24 microns conducted in Guaranteed Time. Using stacking analyses we demonstrate a striking correspondence between the galaxies contributing the submm extragalactic background light, with those likely to dominate the backgrounds at Spitzer wavelengths. Using a combination BRIzK plus Spitzer photometric redshifts, we show that at least a third of the Spitzer-identified submm galaxies at 1 and specific star formation rates <(1/M)dM/dt> are in striking disagreement with some semi-analytic predictions from the Millenium simulation. The discrepancy could either be resolved with a top-heavy initial mass function, or a significant component of the submm flux heated by the interstellar radiation field.
Comment: Accepted by MNRAS. SMG environments analysis extended. 17 pages, 18 figures. Includes BoxedEPS