Bahram Mobasher

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A comparative study of the rest-frame morphology and structural properties of optically selected starburst galaxies at redshift z 1 is carried out using multi-waveband (BV iz) high resolution images taken by the Advanced Camera for Surveys (ACS) as part of the Great Observatories Origins Deep Survey (GOODS). We classify galaxies into starburst, early and(More)
We have discovered 21 new Type Ia supernovae (SNe Ia) with the Hubble Space Telescope (HST) and have used them to trace the history of cosmic expansion over the last 10 billion yr. These objects, which include 13 spectro-scopically confirmed SNe Ia at z ! 1, were discovered during 14 epochs of reimaging of the GOODS fields North and South over 2 yr with the(More)
Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious 'dark matter' component, which does not interact via electromagnetism and thus neither emits nor reflects light. As dark matter cannot be seen directly using traditional observations, very little is(More)
We present the first results from the Australia Telescope Large Area Survey, which consists of deep radio observations of a 3.7 deg 2 field surrounding the Chandra Deep Field–South, largely coincident with the infrared Spitzer Wide-Area Infrared Extragalactic (SWIRE) Survey. We also list cross-identifications to infrared and optical photom-etry data from(More)
We present a three-dimensional cosmic shear analysis of the Hubble Space Telescope COSMOS survey, the largest ever optical imaging program performed in space. We have measured the shapes of galaxies for the telltale distortions caused by weak gravitational lensing and traced the growth of that signal as a function of redshift. Using both 2D and 3D analyses,(More)
Results of a blind test of photometric redshift predictions against spectroscopic galaxy redshifts obtained in the Hubble Deep Field with the Keck Telescope are presented. The best photometric redshift schemes predict spectroscopic redshifts with a redshift accuracy of |∆z| < 0.1 for more than 68 percent of sources and with |∆z| < 0.3 for 100 percent, when(More)
We use a sample of 42 supernovae detected with the Advanced Camera for Surveys on-board the Hubble Space Telescope as part of the Great Observatories Origins Deep Survey to measure the rate of core collapse supernovae to z ∼ 0.7 and type Ia supernovae to z ∼ 1.6. This significantly increases the redshift range where supernova rates have been estimated from(More)
We follow the galaxy stellar mass assembly by morphological and spectral type in the COSMOS 2-deg 2 field. We derive the stellar mass functions and stellar mass densities from z = 2 to z = 0.2 using 192,000 galaxies selected at F 3.6µm > 1µJy with accurate photometric redshifts (σ (z phot −zspec)/(1+zspec) ∼ 0.012). Using a spectral classification, we find(More)