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We examine whether the super star-forming clumps (R~1-3 kpc; M~10^8-10^9.5 Msun) now known to be a key component of star-forming galaxies at z~2 could be the formation sites of the locally observed old globular cluster population. We find that the stellar populations of these super star-forming clumps are excellent matches to those of local metal-rich globular clusters. Moreover, this globular cluster population is known to be associated with the bulges / thick disks of galaxies, and we show that its spatial distribution and kinematics are consistent with the current understanding of the assembly of bulges and thick disks from super star-forming clumps at high redshift. Finally, with the assumption that star formation in these clumps proceeds as a scaled-up version of local star formation in molecular clouds, this formation scenario reproduces the observed numbers and mass spectra of metal-rich globular clusters. The resulting link between the turbulent and clumpy disks observed in high-redshift galaxies and a local globular cluster population provides a plausible co-evolutionary scenario for several of the major components of a galaxy: the bulge, the thick disk, and one of the globular cluster populations.
We study the star formation rates (SFRs) of galaxies as a function of local galaxy density at 0.6<z<0.9. We used a low-dispersion prism in IMACS on the 6.5-m Baade (Magellan I) telescope to obtain spectra and measured redshifts to a precision of sigm
We study the properties of a sample of 211 heavily-obscured Active Galactic Nucleus (AGN) candidates in the Extended Chandra Deep Field-South selecting objects with f_24/f_R>1000 and R-K>4.5. Of these, 18 were detected in X-rays and found to be obscu
We study the structural evolution of massive galaxies by linking progenitors and descendants at a constant cumulative number density of n_c=1.4x10^{-4} Mpc^{-3} to z~3. Structural parameters were measured by fitting Sersic profiles to high resolution
Even 10 billion years ago, the cores of the first galaxy clusters are often found to host a characteristic population of massive galaxies with already suppressed star formation. Here we search for distant cluster candidates at z~2 using massive passi
We present first results of a study aimed to constrain the star formation rate and dust content of galaxies at z~2. We use a sample of BzK-selected star-forming galaxies, drawn from the COSMOS survey, to perform a stacking analysis of their 1.4 GHz r