Infrared luminous Lyman break galaxies:: A population that bridges LBGs and scuba galaxies

A deep mid- and far-infrared survey in the extended Groth strip (EGS) area gives 3.6 to 8 mu m flux densities or upper limits for 253 Lyman break galaxies (LBGs). The LBGs are a diverse population but with properties correlated with luminosity. The LBGs show a factor of 30 range in indicated stellar mass and a factor of 10 range in apparent dust content relative to stellar mass. About 5% of LBGs are luminous at all wavelengths, with powerful emission at rest 6 mu m. In the rest 0.9 to 2 mu m spectral range these galaxies have stellar spectral slopes with no sign of an AGN power-law component, suggesting that their emission is mainly powered by intensive star formation. Galaxies in this luminous population share the infrared properties of cold Submillimeter Common-User Bolometric Array (SCUBA) sources: both are massive and dusty starburst galaxies at 2 < z < 3; their stellar mass is larger than 10(11) M-circle dot. We suggest that these galaxies are the progenitors of present-day giant elliptical galaxies, with a substantial fraction of their stars already formed at z approximate to 3.