Search Publications
Final Results from the Hubble Space Telescope Key Project to Measure the Hubble Constant
Kelson, Daniel D.; Illingworth, Garth D.; Huchra, John P. +12 more
We present here the final results of the Hubble Space Telescope (HST) Key Project to measure the Hubble constant. We summarize our method, the results, and the uncertainties, tabulate our revised distances, and give the implications of these results for cosmology. Our results are based on a Cepheid calibration of several secondary distance methods…
Interpreting the Cosmic Infrared Background: Constraints on the Evolution of the Dust-enshrouded Star Formation Rate
Elbaz, D.; Chary, R.
The mid-infrared local luminosity function is evolved with redshift to fit the spectrum of the cosmic infrared background (CIRB) at λ>5 µm and the galaxy counts from various surveys at mid-infrared, far-infrared, and submillimeter wavelengths. A variety of evolutionary models provide satisfactory fits to the CIRB and the number counts. Th…
The Farthest Known Supernova: Support for an Accelerating Universe and a Glimpse of the Epoch of Deceleration
Dickinson, Mark; Casertano, Stefano; Filippenko, Alexei V. +16 more
We present photometric observations of an apparent Type Ia supernova (SN Ia) at a redshift of ~1.7, the farthest SN observed to date. The supernova, SN 1997ff, was discovered in a repeat observation by the Hubble Space Telescope (HST) of the Hubble Deep Field-North (HDF-N) and serendipitously monitored with NICMOS on HST throughout the Thompson et…
The Rest-Frame Optical Spectra of Lyman Break Galaxies: Star Formation, Extinction, Abundances, and Kinematics
Dickinson, Mark; Giavalisco, Mauro; Pettini, Max +5 more
We present the first results of a spectroscopic survey of Lyman break galaxies (LBGs) in the near-infrared aimed at detecting the emission lines of [O II], [O III], and Hβ from the H II regions of normal star-forming galaxies at z~=3. From observations of 15 objects with the Keck telescope and the Very Large Telescope augmented with data from the …
On the Temporal Relationship between Coronal Mass Ejections and Flares
Zhang, J.; Howard, R. A.; Kundu, M. R. +2 more
The temporal relationship between coronal mass ejections (CMEs) and associated solar flares is of great importance to understanding the origin of CMEs, but it has been difficult to study owing to the nature of CME detection. In this paper, we investigate this issue using the Large Angle and Spectrometric Coronagraph and the EUV Imaging Telescope o…
The Stellar Populations and Evolution of Lyman Break Galaxies
Papovich, Casey; Dickinson, Mark; Ferguson, Henry C.
Using deep near-infrared and optical observations of the Hubble Deep Field-North from the Hubble Space Telescope NICMOS and WFPC2 instruments and from the ground, we examine the spectral energy distributions (SEDs) of Lyman break galaxies (LBGs) at 2.0<~z<~3.5 in order to investigate their stellar population properties. The ultraviolet-optic…
Hubble Space Telescope Time-Series Photometry of the Transiting Planet of HD 209458
Burrows, Adam; Gilliland, Ronald L.; Charbonneau, David +2 more
We have observed four transits of the planet of HD 209458 using the STIS spectrograph on the Hubble Space Telescope (HST). Summing the recorded counts over wavelength between 582 and 638 nm yields a photometric time series with 80 s time sampling and relative precision of about 1.1×10-4 per sample. The folded light curve can be fitted w…
Infrared Space Observatory's Discovery of C4H2, C6H2, and Benzene in CRL 618
Waters, L. B. F. M.; Cernicharo, José; Tielens, A. G. G. M. +4 more
We report on the detection with the Infrared Space Observatory (ISO), for the first time in the circumstellar medium, of the polyacetylenic chains C4H2 and C6H2 and of benzene (C6H6) in the direction of the proto-planetary nebula CRL 618. Surprisingly, the abundances of di- and tria…
Observational Constraints on the Formation and Evolution of Binary Stars
Ghez, A. M.; White, R. J.
We present a high spatial resolution multiwavelength survey of 44 young binary star systems in Taurus-Auriga with separations of 10-1000 AU. These observations, which were obtained using the Hubble Space Telescope and the NASA Infrared Telescope Facility, quadruple the number of close (less than 100 AU) binary stars with spatially resolved measure…
The Infrared Spectral Energy Distribution of Normal Star-forming Galaxies
Dale, Daniel A.; Helou, George; Silbermann, Nancy A. +2 more
We present a new phenomenological model for the spectral energy distribution of normal star-forming galaxies between 3 and 1100 µm. A sequence of realistic galaxy spectra are constructed from a family of dust emission curves assuming a power-law distribution of dust mass over a wide range of interstellar radiation fields. For each interstell…