Previous   |   Session 63   |   Next  |   Author Index   |   Block Schedule

[63.22] Constraints to the Early Galaxy Mass Assembly History as Revealed by the GOODS Spitzer/IRAC Observations

H. Yan (Spitzer Science Center, Caltech), GOODS Team

The deep Infrared Array Camera (IRAC) observations of the Great Observatories Origins Deep Survey (GOODS) Spitzer Legacy Program have detected field Lyman-break galaxies at z ~ 6. At this redshift regime, the IRAC observations measure the rest-frame optical fluxes from these galaxies, which are less prone to dust extinction and less sensitive to short-lived stars. In our earlier study of the high-z galaxies in the Hubble Ultra Deep Field, we have found that some very massive galaxies (~ a few 1e10 solar mass) with ages of a few hundred million years were already in place by z ~ 6. Here we report the most recent results from the study of the entire GOODS fields, HDF-N and CDF-S. In particular, using the GOODS Ultra-deep IRAC observations in the HDF-N, we are able to stringently constrain the mass upper limit of the z ~ 6 galaxies that are not detected by the IRAC.

Previous   |   Session 63   |   Next

Bulletin of the American Astronomical Society, 37 #4
© 2005. The American Astronomical Soceity.