Search Publications
Type Ia Supernova Discoveries at z > 1 from the Hubble Space Telescope: Evidence for Past Deceleration and Constraints on Dark Energy Evolution
Dickinson, Mark; Ferguson, Henry C.; Giavalisco, Mauro +16 more
We have discovered 16 Type Ia supernovae (SNe Ia) with the Hubble Space Telescope (HST) and have used them to provide the first conclusive evidence for cosmic deceleration that preceded the current epoch of cosmic acceleration. These objects, discovered during the course of the GOODS ACS Treasury program, include 6 of the 7 highest redshift SNe Ia…
The Great Observatories Origins Deep Survey: Initial Results from Optical and Near-Infrared Imaging
Cesarsky, C.; Wolf, C.; Jogee, S. +54 more
This special issue of the Astrophysical Journal Letters is dedicated to presenting initial results from the Great Observatories Origins Deep Survey (GOODS) that are primarily, but not exclusively, based on multiband imaging data obtained with the Hubble Space Telescope and the Advanced Camera for Surveys (ACS). The survey covers roughly 320 arcmin…
A New Photometric Technique for the Joint Selection of Star-forming and Passive Galaxies at 1.4 <~ z <~ 2.5
Cimatti, A.; Daddi, E.; Tozzi, P. +5 more
A simple two-color selection based on B-, z-, and K-band photometry is proposed for culling galaxies at 1.4<~z<~2.5 in K-selected samples and classifying them as star-forming or passive systems. The method is calibrated on the highly complete spectroscopic redshift database of the K20 survey, verified with simulations and tested on other dat…
Detection of Oxygen and Carbon in the Hydrodynamically Escaping Atmosphere of the Extrasolar Planet HD 209458b
Ehrenreich, D.; Lecavelier des Etangs, A.; Ferlet, R. +7 more
Four transits of the planet orbiting the star HD 209458 were observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. The wavelength domain (1180-1710 Å) includes H I as well as C I, C II, C IV, N V, O I, S I, Si II, Si III, and Si IV lines. During the transits, absorptions are detected in H I, O I, and C II (5%+…
ω Centauri: The Population Puzzle Goes Deeper
Anderson, Jay; Bedin, Luigi R.; Piotto, Giampaolo +4 more
We present Hubble Space Telescope observations that show a bifurcation of colors in the middle main sequence of the globular cluster ω Centauri. We see this in three different fields, observed with different cameras and filters. We also present high-precision photometry of a central Advanced Camera for Surveys field, which shows a number of main-s…
Twenty-Three High-Redshift Supernovae from the Institute for Astronomy Deep Survey: Doubling the Supernova Sample at z > 0.7
Filippenko, Alexei V.; Wainscoat, Richard J.; Garnavich, Peter +29 more
We present photometric and spectroscopic observations of 23 high-redshift supernovae (SNe) spanning a range of z=0.34-1.03, nine of which are unambiguously classified as Type Ia. These SNe were discovered during the IfA Deep Survey, which began in 2001 September and observed a total of 2.5 deg2 to a depth of approximately m~25-26 in RIZ…
The Rest-Frame Ultraviolet Luminosity Density of Star-forming Galaxies at Redshifts z>3.5
Gardner, Jonathan P.; Stern, D.; Dickinson, M. +12 more
We have measured the rest-frame λ~1500 Å comoving specific luminosity density of star-forming galaxies at redshift 3.5<z<6.5 (Lyman break galaxies [LBGs]) selected from deep, multiband images taken with the Hubble Space Telescope and the Advanced Camera for Surveys, obtained as part of the Great Observatories Origins Deep Survey (GOODS). The…
Massive Dark Matter Halos and Evolution of Early-Type Galaxies to z ~ 1
Treu, Tommaso; Koopmans, Léon V. E.
The combination of gravitational lensing and stellar dynamics breaks the mass-anisotropy degeneracy and provides stringent constraints on the distribution of luminous and dark matter in early-type (E/S0) galaxies out to z~1. We present new observations and models of three lens systems (CFRS 03.1077, HST 14176+5226, HST 15433+5352) and the combined…
The Size Evolution of High-Redshift Galaxies
Dickinson, Mark; Ferguson, Henry C.; Giavalisco, Mauro +14 more
Hubble Space Telescope images of high-redshift galaxies selected via color and photometric redshifts are used to examine the size and axial ratio distribution of galaxies as a function of redshift at look-back times t>8 Gyr. These parameters are measured at rest-frame UV wavelengths (1200 Å < λ < 2000 Å) on images with a rest-frame resolu…
The Helium Abundances of ω Centauri
Norris, John E.
Recent Hubble Space Telescope color magnitude diagrams (CMDs) of ω Centauri, which clearly show three sequences in the region of the main-sequence turnoff together with a double lower main sequence, are explained in terms of three populations having canonical heavy-element abundances ([Fe/H]=-1.7, -1.2, and -0.6), reasonable proportions and ages, …