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…
Cosmic-Ray Rejection by Laplacian Edge Detection
van Dokkum, Pieter G.
Conventional algorithms for rejecting cosmic rays in single CCD exposures rely on the contrast between cosmic rays and their surroundings and may produce erroneous results if the point-spread function is smaller than the largest cosmic rays. This paper describes a robust algorithm for cosmic-ray rejection, based on a variation of Laplacian edge de…
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 …
The SAURON project - I. The panoramic integral-field spectrograph
Emsellem, Eric; Miller, Bryan W.; Carollo, C. M. +10 more
A new integral-field spectrograph, SAURON, is described. It is based on the TIGER principle, and uses a lenslet array. SAURON has a large field of view and high throughput, and allows simultaneous sky subtraction. Its design is optimized for studies of the stellar kinematics, gas kinematics, and line-strength distributions of nearby early-type gal…
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…
An Empirical Ultraviolet Template for Iron Emission in Quasars as Derived from I Zwicky 1
Vestergaard, M.; Wilkes, B. J.
We present an empirical template spectrum suitable for fitting and subtracting/studying the Fe II and Fe III emission lines in the rest frame ultraviolet spectra of quasars and active galactic nuclei, the first empirical ultraviolet iron template to cover the full range of 1250-3090 Å. Iron emission is often a severe contaminant in optical-ultravi…
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…
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 Metamorphosis of SN 1998bw
Leibundgut, Bruno; Kouveliotou, Chryssa; Nomoto, Ken'ichi +23 more
We present and discuss the photometric and spectroscopic evolution of the peculiar SN 1998bw, associated with GRB 980425, through an analysis of optical and near-IR data collected at ESO-La Silla. The spectroscopic data, spanning the period from day -9 to day +376 (relative to B maximum), have shown that this supernova (SN) was unprecedented, alth…