Timothy M. Heckman

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The Sloan Digital Sky Survey (SDSS) will provide the data to support detailed investigations of the distribution of luminous and non-luminous matter in the Universe: a photometrically and astrometrically calibrated digital imaging survey of π steradians above about Galactic latitude 30◦ in five broad optical bands to a depth of g′ ∼ 23, and a spectroscopic(More)
This paper describes the Sixth Data Release of the Sloan Digital Sky Survey.With this data release, the imaging of the northern Galactic cap is now complete. The survey contains images and parameters of roughly 287 million objects over 9583 deg, including scans over a large range of Galactic latitudes and longitudes. The survey also includes 1.27 million(More)
This paper describes the Fifth Data Release (DR5) of the Sloan Digital Sky Survey (SDSS). DR5 includes all survey quality data taken through June 2005 and represents the completion of the SDSS-I project (whose successor, SDSSII will continue through mid-2008). It includes five-band photometric data for 217 million objects selected over 8000 deg, and(More)
We give an overview of the Galaxy Evolution Explorer (GALEX), a NASA Explorer Mission launched on April 28, 2003. GALEX is performing the first space UV sky-survey, including imaging and grism surveys in two bands (1350-1750Å and 1750-2750Å). The surveys include an all-sky imaging survey (mAB ≃ 20.5), a medium imaging survey of 1000 deg (mAB ≃ 23), a deep(More)
Starburst99 is a comprehensive set of model predictions for spectrophotometric and related properties of galaxies with active star formation. The models are an improved and extended version of the data set previously published by Leitherer & Heckman (1995). We have upgraded our code by implementing the latest set of stellar evolution models of the Geneva(More)
The Sloan Digital Sky Survey has validated and made publicly available its First Data Release. This consists of 2099 square degrees of five-band (u g r i z) imaging data, 186,240 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 1360 square degrees of this area, and tables of measured parameters from these data. The imaging(More)
The Sloan Digital Sky Survey has validated and made publicly available its Second Data Release. This data release consists of 3324 square degrees of five-band (u g r i z) imaging data with photometry for over 88 million unique objects, 367,360 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 2627 degrees of 31 Enrico Fermi(More)
We refine a technique to measure the absorption corrected ultraviolet (UV) luminosity of starburst galaxies using rest frame UV quantities alone, and apply it to Lyman-limit U -dropouts at z ≈ 3 found in the Hubble Deep field (HDF). The method is based on an observed correlation between the ratio of far infrared (FIR) to UV fluxes with spectral slope β (a(More)
We have compiled a large sample of low-redshift active galactic nuclei (AGN) identified via their emission line characteristics from the spectroscopic data of the Sloan Digital Sky Survey. Since emission lines are often contaminated by stellar absorption lines, we developed an objective and efficient method of subtracting the stellar continuum from every(More)