2006-07-20

high-redshift star formation

Davé's students Finlator and Oppenheimer gave nice talks today about high-redshift star formation in numerical models of structure and galaxy formation. Finlator showed that the star-formation histories of galaxies at early times are very constrained (if the star-formation prescriptions in the models are close to correct); this will either aid strongly the fitting of high-redshift spectral energy distributions of galaxies, or else show that there are issues with their numerical simulation of cosmic star formation. Oppenheimer showed that the long-debated early enrichment of the IGM, which has been suggested because CIV (triply ionized carbon) is seen at all redshifts, is something of a coincidence; the carbon abundance is rising, but the fraction of the carbon in CIV form is falling. Though it looks like the IGM was polluted early and only once, in fact pollution has been a continuous process; there is no requirement of any Pop III stars to enrich the IGM at early times.

Rix, Bell, and a cast of thousands argued this afternoon about how the black hole masses know about their host bulge masses. Some predictions were made.

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