Previous | Session 128 | Next
R. Bouwens, G. Illingworth (UC Santa Cruz), R. Thompson (U of Arizona)
Data from the Hubble Ultra Deep Field and its associated parallel fields constitute the deepest optical and infrared looks ever taken of the universe. Not only do these fields provide unprecedented measures of the number of faint galaxies at z~4-6, but these data permit meaningful constraints on early galaxy formation out to redshifts as high as 12. Impressively, these data have already allowed us to obtain samples of candidate z~7-8 objects and to set some upper limits on the number of bright objects at earlier redshifts (z~8-12). Early studies point towards there being a deficit of objects at the bright end relative to lower redshifts and towards galaxies having a much steeper faint end slope. This suggests that the majority of galaxies were much smaller at early times, as expected in hierarchical scenarios of galaxy formation.
Previous | Session 128 | Next
Bulletin of the American Astronomical Society, 36 5
© 2004. The American Astronomical Society.