Benjamin J. Weiner

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The quantitative morphological classification of distant galaxies is essential to the understanding of the evolution of galaxies over the history of the Universe. This paper presents Hubble Space Telescope WFPC2 F 606W and F 814W photometric structural parameters for 7450 galaxies in the " Groth Strip. " These parameters are based on a two-dimensional(More)
We present a Principal Component Analysis (PCA)-based spectral classification, η, for the first 5600 galaxies observed in the DEEP2 Redshift Survey. This parameter provides a very pronounced separation between absorption and emission dominated galaxy spectra – corresponding to passively evolving and actively star-forming galaxies in the survey respectively.(More)
Stars form from cold molecular interstellar gas. As this is relatively rare in the local Universe, galaxies like the Milky Way form only a few new stars per year. Typical massive galaxies in the distant Universe formed stars an order of magnitude more rapidly. Unless star formation was significantly more efficient, this difference suggests that young(More)
We characterize the mass-dependent evolution in a large sample of more than 8,000 galaxies using spectroscopic redshifts drawn from the DEEP2 Galaxy Redshift Survey in the range 0.4 < z < 1.4 and stellar masses calculated from K-band photometry obtained at Palomar Observatory. This sample spans more than 1.5 square degrees in four independent fields. Using(More)
We have detected faint Hα emission from several points along the Magellanic Stream, using the Rutgers Fabry–Perot Interferometer at the CTIO 1.5-m telescope. The sources of the emission are diffuse; at each observed position, there is no variation in intensity over the 7 ′ field of the Fabry–Perot. At points on the leading edges of the H I clouds MS II, MS(More)
Fundamental Plane studies provide an excellent means of understanding the evolutionary history of early-type galaxies. Using the Low Resolution Imaging Spectrograph on the Keck telescope, we obtained internal stellar kinematic information for 36 field galaxies in the Groth Strip—21 early-type and 15 disk galaxies. Their redshifts range from 0.3–1.0, with a(More)
1 Summary Astronomical software is now a fact of daily life for all hands-on members of the astronomy and astrophysics community. Purpose-built software to assist in and automate data reduction and modeling tasks becomes ever more critical as we handle larger amounts of data and simulations and doing steps " by hand " becomes less practical. However, the(More)
1 Based on observations obtained at the W. M. Keck Observatory, which is operated jointly by the University of California and the California Institute of Technology and on observations made with the NASA/ESA Hubble Space Telescope (HST) obtained from the data Archive at the Space Telescope Science Institute (STScI), which is operated by the Association of(More)
The Deep Extragalactic Evolutionary Probe (DEEP) is a series of spectroscopic surveys of faint galaxies, targeted at understanding the properties and clustering of galaxies at redshifts z ∼ 1. We present the redshift catalog of the DEEP 1 Groth Strip pilot phase of this project, a Keck/LRIS survey of faint galaxies in the Groth Survey Strip imaged with HST(More)
We report a dynamical determination of the separate contributions of disk and dark halo masses to the rotation curve of a spiral galaxy. We use fluid-dynamical models of gas flow in the barred galaxy NGC 4123 to constrain the dynamical properties of the galaxy: disk M/L, bar pattern speed, and the central density and scale radius of the dark halo. We derive(More)