LATE REIONIZATION BY SUPERNOVA-DRIVEN WINDS

A model is presented in which supernova-driven winds from early galaxi es reionize the intergalactic medium by z = 5. This scenario can expla in the observed absence of a Gunn-Peterson trough in the spectra of hi gh-redshift quasars providing that the bulk of these early galaxies ar e quite small, no more massive than about 10(8) M.. It also predicts t hat most of the IGM was enriched to at least 10% of current metal cont ent by z = 5 and perhaps as early as z = 15. The existence of such ear ly minigalaxies violated no spectral constraints and is consistent wit h a pure CDM model with b less-than-or-equal-to 2. Since the final rad ius of a typical ionized bubble is only around 100 kpc, the induced mo dification of the galaxy autocorrelation function is negligible, as is the induced angular smoothing of the CMBR. Some of the gas swept up b y shells may be observable as pressure-supported Lyman-al ha forest cl uds.