The ACS grism mode offers an unprecedented opportunity to obtain slit-less, highly multiplexed, spectroscopic observations down to very faint magnitudes. In this paper, we show that by selecting objects in a deep field based in the spectra of these objects rather than their broad band colors, a more accurate object selection can be performed. The ACS grism mode enabled us to identify faint, young, and low mass (≈106 –108 M⊙) galaxies at 4.0 <z <5.7, that are likely to be the building blocks leading to the assembly of the more massive galaxies that we observed in the present universe.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Computer Science Applications
- Space and Planetary Science
- Nuclear and High Energy Physics