Showing 2003 · astro-phShow all

58 papers · 2 filters

astro-ph2003★ 118 cited

Observations and Theoretical Implications of the Large Separation Lensed Quasar SDSS J1004+4112

M. Oguri, N. Inada, C. R. Keeton +25

We study the recently discovered gravitational lens SDSS J1004+4112, the first quasar lensed by a cluster of galaxies. It consists of four images with a maximum separation of 14.62…

astro-ph2003★ 28 cited

A Survey of Open Clusters in the u'g'r'i'z' Filter System: I. Results for NGC2548 (M48)

Cristin J. Rider, Douglas L. Tucker, J. Allyn Smith +3

We present initial results of a photometric survey of open star clusters, primarily in the southern hemisphere, taken in the u'g'r'i'z' filter system. While our entire observed sam…

astro-ph2003★ 93 cited

A Catalog of Compact Groups of Galaxies in the SDSS Commissioning Data

B. C. Lee, S. S. Allam, D. L. Tucker +20

Compact groups (CGs) of galaxies -- relatively poor groups of galaxies in which the typical separations between members is of the order of a galaxy diameter -- offer an exceptional…

astro-ph2003★ 210 cited

A Gravitationally Lensed Quasar with Quadruple Images Separated by 14.62 Arcseconds

N. Inada, M. Oguri, B. Pindor +29

Gravitational lensing is a powerful tool for the study of the distribution of dark matter in the Universe. The cold-dark-matter model of the formation of large-scale structures pre…

astro-ph2003★ 2 cited

Ultra-High Energy Cosmic Rays from Quasar Remnants

C. Isola, G. Sigl, G. Bertone

One of the models recently proposed to explain the origin of the ultra high energy cosmic rays assumes that these particles may be accelerated by the electromotive force around pre…

astro-ph2003★ 54 cited

Isolating Geometry in Weak Lensing Measurements

Jun Zhang, Lam Hui, Albert Stebbins

Given a foreground galaxy-density field or shear field, its cross-correlation with the shear field from a background population of source galaxies scales with the source redshift i…

astro-ph2003★ 34 cited

Merging Galaxies in the SDSS EDR

S. S. Allam, D. L. Tucker, J. A. Smith +5

We present a new catalog of merging galaxies obtained through an automated systematic search routine. The 1479 new pairs of merging galaxies were found in approximately 462 sq deg…

astro-ph2003★ 47 cited

SDSS J115517.35+634622.0: A Newly Discovered Gravitationally Lensed Quasar

Bart Pindor, Daniel J. Eisenstein, Naohisa Inada +12

We report the discovery of SDSSJ115517.35+634622.0, a previously unknown gravitationally lensed quasar. The lens system exhibits two images of a quasar, with an image se…

astro-ph2003★ 13 cited

Microlensing of gamma ray bursts by stars and MACHOs

Edward A. Baltz, Lam Hui

The microlensing interpretation of the optical afterglow of GRB 000301C seems naively surprising, since a simple estimate of the stellar microlensing rate gives less than one in fo…

astro-ph2003★ 46 cited

SDSS J1335+0118: A New Two-Image Gravitational Lens

Masamune Oguri, Naohisa Inada, Francisco J. Castander +13

We report the discovery of the two-image gravitationally lensed quasar SDSS J1335+0118. The object was selected as a lens candidate from the Sloan Digital Sky Survey. The imaging a…

astro-ph2003★ 48 cited

Inflationary potentials yielding constant scalar perturbation spectral indices

Alberto Vallinotto, Edmund J. Copeland, Edward W. Kolb +2

We explore the types of slow-roll inflationary potentials that result in scalar perturbations with a constant spectral index, i.e., perturbations that may be described by a single…

astro-ph2003★ 2 cited

Void Hierarchy and Cosmic Structure

Rien van de Weygaert, Ravi Sheth

Within the context of hierarchical scenarios of gravitational structure formation we describe how an evolving hierarchy of voids evolves on the basis of {\em two} processes, the {\…

astro-ph2003

Luminosity and Redshift Dependence of Quasar Spectral Properties

D. E. Vanden Berk, C. -Y. Yip, A. J. Connolly +2

Using a large sample of quasar spectra from the SDSS, we examine the composite spectral trends of quasars as functions of both redshift and luminosity, independently of one another…

astro-ph2003★ 1.8k cited

The 3D power spectrum of galaxies from the SDSS

M Tegmark, M Blanton, M Strauss +32

We measure the large-scale real-space power spectrum P(k) using a sample of 205,443 galaxies from the Sloan Digital Sky Survey, covering 2417 square degrees with mean redshift z~0.…

astro-ph2003

Volume-limited SDSS/FIRST quasars and the radio dichotomy

S. Jester, R. Kron

Much evidence has been presented in favor of and against the existence of two distinct populations of quasars, radio-loud and radio-quiet. The SDSS differs from earlier optically s…

astro-ph2003★ 484 cited

The Ensemble Photometric Variability of ~25000 Quasars in the Sloan Digital Sky Survey

D. E. Vanden Berk, B. C. Wilhite, R. G. Kron +11

Using a sample of over 25000 spectroscopically confirmed quasars from the Sloan Digital Sky Survey, we show how quasar variability in the rest frame optical/UV regime depends upon…

astro-ph2003★ 4k cited

Cosmological parameters from SDSS and WMAP

M. Tegmark, M. Strauss, M. Blanton +34

We measure cosmological parameters using the three-dimensional power spectrum P(k) from over 200,000 galaxies in the Sloan Digital Sky Survey (SDSS) in combination with WMAP and ot…

astro-ph2003★ 43 cited

Cluster Masses Accounting for Structure along the Line of Sight

Scott Dodelson

Weak gravitational lensing of background galaxies by foreground clusters offers an excellent opportunity to measure cluster masses directly without using gas as a probe. One source…

astro-ph2003★ 195 cited

Sagittarius Tidal Debris 90 kpc from the Galactic Center

Heidi Jo Newberg, Brian Yanny, Eva K. Grebel +9

A new overdensity of A-colored stars in distant parts of the Milky Way's stellar halo, at a dereddened SDSS magnitude of g_0 = 20.3, is presented. Identification of associated vari…

astro-ph2003★ 201 cited

The Sloan Digital Sky Survey Quasar Catalog II. First Data Release

Donald P. Schneider, Xiaohui Fan, Patrick B. Hall +13

We present the second edition of the Sloan Digital Sky Survey (SDSS) Quasar Catalog. The catalog consists of 16713 objects in the SDSS First Data Release (DR1) that have luminositi…

astro-ph2003★ 11 cited

The effect of cluster magnetic field on the Sunyaev Zeldovich power spectrum

Pengjie Zhang

Precision measurements of the Sunyaev Zeldovich (SZ) effect in upcoming blank sky surveys require theoretical understanding of all physical processes with $\ga 10%$ effects on the…

astro-ph2003★ 332 cited

The extended tails of Palomar 5: A ten degree arc of globular cluster tidal debris

M. Odenkirchen, E. K. Grebel, W. Dehnen +7

Using wide-field photometric data from the Sloan Digital Sky Survey (SDSS) we recently showed that the Galactic globular cluster Palomar 5 is in the process of being tidally disrup…

astro-ph2003★ 58 cited

SDSS J0903+5028: A New Gravitational Lens

David E. Johnston, Gordon T. Richards, Joshua A. Frieman +22

We report the discovery of a new gravitationally lensed quasar from the Sloan Digital Sky Survey, SDSS J090334.92+502819.2. This object was targeted for SDSS spectroscopy as a Lumi…

astro-ph2003★ 78 cited

Large Scale Structure in the SDSS DR1 Galaxy Survey

A. Doroshkevich, D. L. Tucker, S. Allam +1

The Large Scale Structure in the galaxy distribution is investigated using The First Data Release of the Sloan Digital Sky Survey. Using the Minimal Spanning Tree technique we have…