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We present the results of NICMOS imaging of two massive galaxies photometrically selected to have old stellar populations at z ~ 2.5. Both galaxies are dominated by apparent disks of old stars, although one of them also has a small bulge comprising about 1/3 of the light at rest-frame 4800 A. The presence of massive disks of old stars at high redshift means that at least some massive galaxies in the early universe have formed directly from the dissipative collapse of a large mass of gas. The stars formed in disks like these may have made significant contributions to the stellar populations of massive spheroids at the present epoch.
We describe a study of morphologies of galaxies with old stellar populations in radio-source fields at z ~ 2.5. A significant fraction of these are dominated by disks of old stars, and none we have found so far has the properties of present-epoch ell
We describe observations of a galaxy in the field of the $z=2.483$ radio galaxy 4C 23.56, photometrically selected to have a spectral-energy distribution consistent with an old stellar population at the redshift of the radio galaxy. Exploration of re
We have used high-resolution, HST WFC3/IR, near-infrared imaging to conduct a detailed bulge-disk decomposition of the morphologies of ~200 of the most massive (M_star > 10^11 M_solar) galaxies at 1<z<3 in the CANDELS-UDS field. We find that, while s
We present preliminary results on 24micron detections of luminous infrared galaxies at z>1 with the Multiband Imaging Photometer for Spitzer (MIPS). Observations were performed in the Lockman Hole and the Extended Groth Strip (EGS), and were suppleme
Fundamental properties of the extinction curve, like the slope in the rest-frame ultraviolet (UV) and the presence/absence of a broad absorption excess centred at 2175 A (the UV bump), are investigated for a sample of 108 massive, star-forming galaxi