19.6k citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Kitt Peak National ObservatoryUS401 papers
- Cerro Tololo Inter-American ObservatoryCL274 papers
- U.S. National Science FoundationUS162 papers
- Space Telescope Science InstituteUS159 papers
- California Institute of TechnologyUS116 papers
- University of ArizonaUS99 papers
- Center for Astrophysics Harvard & SmithsonianUS80 papers
- Johns Hopkins UniversityUS71 papers
- University of California, BerkeleyUS58 papers
- University of Wisconsin–MadisonUS58 papers
- Carnegie ObservatoriesUS57 papers
- Goddard Space Flight CenterUS56 papers
56 papers · 2 filters
CCD uvbyHbeta Photometry in Clusters: I. The Open Cluster Standard, IC 4651
B. J. Anthony-Twarog, B. A. Twarog
CCD photometry of the intermediate-age open cluster, IC 4651, on the uvbyHbeta system is presented and analyzed. By using a combination of the information from the color-magnitude…
The Reappearance of the Transient Low Mass X-ray Binary X1658-298
Stefanie Wachter, Alan P. Smale, Charles Bailyn
In April 1999 the transient low mass X-ray binary X1658-298 resumed its strong and persistent X-ray emission after a 21-year interval of quiescence. We present RXTE data obtained s…
The Neutral Hydrogen Distribution in Merging Galaxies: Differences between Stellar and Gaseous Tidal Morphologies
J. E. Hibbard, W. D. Vacca, M. S. Yun
We have mapped the neutral atomic gas (HI) in the three disk-disk merger systems NGC 520, Arp 220, and Arp 299. These systems differ from the majority of the mergers mapped in HI,…
Calibration of Nebular Emission-Line Diagnostics: I. Stellar Effective Temperatures
M. S. Oey, M. A. Dopita, J. C. Shields +1
We present a detailed comparison of optical H II region spectra to photoionization models based on modern stellar atmosphere models. We examine both spatially resolved and integrat…
The Butcher-Oemler Effect at Moderate Redshift
Anne J. Metevier, A. Kathy Romer, M. P. Ulmer
We present the results of Butcher-Oemler-style analysis of three moderate- redshift (0.1<z<0.2) clusters which have bimodal X-ray surface brightness profiles. We find that at least…
Molecular Gas, Dust and Star Formation in the Barred Spiral NGC 5383
Kartik Sheth, Michael W. Regan, Stuart N. Vogel +1
We present multi-wavelength (interferometer and single-dish CO J=1-0, Halpha, broadband optical and near-infrared) observations of the classic barred spiral NGC 5383. We compare th…
Identification of SH ro-vibrational lines in R And
I. Yamamura, K. Kawaguchi, S. T. Ridgway
We report the identification of SH ro-vibrational lines in the published high-resolution infrared spectrum of the S-type star, R And. This is the first astronomical detectio…
Weak Gravitational Lensing by the Nearby Cluster Abell 3667
M. Joffre, P. Fischer, J. Frieman +6
We present two weak lensing reconstructions of the nearby () merging cluster Abell 3667, based on observations taken year apart under different seeing condit…
Evidence for Large Scale Structure in the Lyman alpha Forest at z>2.6
G. M. Williger, A. Smette, C. Hazard +2
We present a search for spatial and redshift correlations in a 2 A resolution spectroscopic survey of the Lyman alpha forest at 2.15 < z < 3.37 toward ten QSOs concentrated within…
A Spectroscopic Study of a Large Sample of Wolf-Rayet Galaxies
N. G. Guseva, Y. I. Izotov, T. X. Thuan
We analyze long-slit spectral observations of 39 Wolf-Rayet (WR) galaxies with heavy element mass fraction ranging over 2 orders of magnitude, from Zsun/50 to 2Zsun. Nearly all gal…
A New Look At Carbon Abundances In Planetary Nebulae. IV. Implications For Stellar Nucleosynthesis
R. B. C. Henry, K. B. Kwitter, J. A. Bates
This paper is the fourth and final report on a project designed to study carbon abundances in a sample of planetary nebulae representing a broad range in progenitor mass and metall…
The Distance to the LMC via the Eclipsing Binary HV 2274
C. A. Nelson, K. H. Cook, P. Popowski +1
We present UBV photometry of the eclipsing binary Harvard Variable 2274 in the Large Magellanic Cloud (LMC). The stellar parameters of this binary system were calculated by Guinan…
Galactic Kinematics Towards the South Galactic Pole. First Results from the Yale-San Juan Southern Proper-Motion Program
René A. Méndez, Imants Platais, Terrence M. Girard +2
The predictions from a Galactic Structure and Kinematic model code are compared to the color counts and absolute proper-motions derived from the Southern Proper-Motion survey cover…
The End of the Lines for OX 169: No Binary Broad-Line Region
J. P. Halpern, M. C. Eracleous
We show that unusual Balmer emission line profiles of the quasar OX 169, frequently described as either self-absorbed or double peaked, are actually neither. The effect is an illus…
FIRST Bent-Double Radio Sources: Tracers of High-Redshift Clusters
E. L. Blanton, M. D. Gregg, D. J. Helfand +2
Bent-double radio sources can act as tracers for clusters of galaxies. We present imaging and spectroscopic observations of the environments surrounding ten of these sources (most…
Keck Spectra of Brown Dwarf Candidates and a Precise Determination of the Lithium Depletion Boundary in the Alpha Persei Open Cluster
J. R. Stauffer, D. Barrado y Navascués, J. Bouvier +8
We have identified twenty-seven candidate very low mass members of the relatively young Alpha Persei open cluster from a six square degree CCD imaging survey. Based on their I magn…
The Extraordinary `Superthin' Spiral Galaxy UGC7321. I. Disk Color Gradients and Global Properties from Multiwavelength Observations
L. D. Matthews, J. S. Gallagher, W. van Driel
We present B- and R-band imaging and photometry, H-alpha narrow-band imaging, NIR H-band imaging, and HI 21-cm spectroscopy of the nearby Sd spiral galaxy UGC7321. UGC7321 exhibits…
The Unusual Infrared Object HDF-N J123656.3+621322
Mark Dickinson, Christopher Hanley, Richard Elston +11
We describe an object in the Hubble Deep Field North with very unusual near-infrared properties. It is readily visible in Hubble Space Telescope NICMOS images at 1.6um and from the…
Abundance Analyses of Field RV Stars, V: DS Aquarii, UY Arae, TW Camelopardis, BT Librae, U Moncerotis, TT Ophiuchi, and RV Tauri
Sunetra Giridhar, David L. Lambert, Guillermo Gonzalez
Abundance analyses are presented and discussed for eight RV Tauri variables. The RV B star UY Ara shows the abundance anomalies seen in other RV B stars, namely elements that conde…
The Luminous Type Ic SN 1992ar at z=0.145
Alejandro Clocchiatti, Mark M. Phillips, Nicholas B. Suntzeff +13
We present spectroscopic and photometric observations of SN1992ar, the more distant SN in the Calan/Tololo Survey. We compare its spectrum with those of nearby Type Ia and Ic SNe a…
Spectrophotometry of HII Regions, Diffuse Ionized Gas and Supernova Remnants in M31: The Transition from Photo- to Shock-Ionization
V. C. Galarza, R. A. M. Walterbos, R. Braun
We present results of KPNO 4-m optical spectroscopy of discrete emission-line nebulae and regions of diffuse ionized gas (DIG) in M31. Long-slit spectra of 16 positions in the NE h…
Evidence for Large-Scale Structure at z=2.4 From Lyman-alpha Imaging
William C. Keel, Seth H. Cohen, Rogier A. Windhorst +1
We present deep wide-field medium-band imaging in redshifted Lyman alpha of fields surrounding HST detections of faint emitters, to characterize their larger-scale environment. The…
Spectroscopic Observations of Optically Selected Clusters of Galaxies from the Palomar Distant Cluster Survey
B. P. Holden, R. C. Nichol, A. K. Romer +4
We have conducted a redshift survey of sixteen cluster candidates from the Palomar Distant Cluster Survey (PDCS) to determine both the density of PDCS clusters and the accuracy of…
Evolution in the Clustering of Galaxies for Z < 1
Robert J. Brunner, Andrew J. Connolly, Alex S. Szalay
Measuring the evolution in the clustering of galaxies over a large redshift range is a challenging problem. For a two-dimensional galaxy catalog, however, we can measure the galaxy…