Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Harvard UniversityUS3.4k papers
- California Institute of TechnologyUS2.8k papers
- Centre National de la Recherche ScientifiqueFR2.4k papers
- University of California, BerkeleyUS2k papers
- Massachusetts Institute of TechnologyUS2k papers
- University of ArizonaUS1.9k papers
- Goddard Space Flight CenterUS1.6k papers
- Space Telescope Science InstituteUS1.6k papers
- Princeton UniversityUS1.5k papers
- Max Planck Institute for AstronomyDE1.4k papers
- Max Planck Institute for Extraterrestrial PhysicsDE1.4k papers
- University of MichiganUS1.3k papers
40 papers · 1 filter
Are There MeV Gamma-Ray Bursts?
Tsvi Piran, Ramesh Narayan
It is often stated that gamma-ray bursts (GRBs) have typical energies of several hundred keV. Is this a real feature of GRBs or is it due to an observational bias? We consider the…
A radio Search for high redshift HI absorption
Jayaram N. Chengalur, A. G. de Bruyn, R. Braun +1
Ground based optical observations have yielded considerable information on the statistics of damped-lyman alpha systems. In particular these systems are known to be the dominant re…
Cosmological Constant and Statistical Lensing of Giant Arcs
Xiang-Ping Wu, Shude Mao
Using a singular isothermal sphere model for the matter distribution of foreground clusters of galaxies, we study the statistics of giant arcs in flat cosmologies with and without…
Reconnecting Magnetic Flux Tubes as a Source of In Situ Acceleration in Extragalactic Radio Sources
Eric G. Blackman
Many extended extragalactic radio sources require a local {\it in situ\/} acceleration mechanism for electrons, in part because the synchrotron lifetimes are shorter than the bulk…
Cosmological-Parameter Determination with Microwave Background Maps
Gerard Jungman, Marc Kamionkowski, Arthur Kosowsky +1
The angular power spectrum of the cosmic microwave background (CMB) contains information on virtually all cosmological parameters of interest, including the geometry of the Univers…
Large-Scale Power-Spectrum from Peculiar Velocities
Tsafrir Kolatt, Avishai Dekel
The power spectrum (PS) of mass density fluctuations, in the range $0.05 \leq k \leq 0.2 \ihmpc$, is derived from the Mark III catalog of peculiar velocities of galaxies, independe…
The Fundamental Plane for cluster E and S0 galaxies
Inger Jorgensen, Marijn Franx, Per Kjaergaard
We have analyzed the Fundamental Plane (FP) for a sample of 226 E and S0 galaxies in ten clusters of galaxies. For photometry in Gunn r the best fitting plane is log r_e=1.24 log s…
LensMEM: A Gravitational Lens Inversion Algorithm Using the Maximum Entropy Method
S. Wallington, C. S. Kochanek, R. Narayan
We present a new algorithm for inverting poorly resolved gravitational lens systems using the maximum entropy method (MEM). We test the method with simulations and then apply it to…
The 2D Power Spectrum of the Las Campanas Redshift Survey: Detection of Excess Power on 100 h^{-1} Mpc Scales
S. D. Landy, S. A. Shectman, H. Lin +3
We have measured the 2 dimensional (2D) power spectrum of the Las Campanas Redshift Survey on scales between 30 and 200 Mpc (q_0=0.5, H_o=100h km sec^{-1} Mpc^{-1}). Such an analys…
Is the Accretion Flow in NGC 4258 Advection-dominated?
J. -P. Lasota, M. A. Abramowicz, X. Chen +3
The mass of the central black hole in the active galaxy NGC 4258 (M106) has been measured to be $M=3.6\times10^7\Msun$ (Miyoshi et al. 1995). The Eddington luminosity corresponding…
Deprojection of Axially Symmetric Objects
C. S. Kochanek, G. B. Rybicki
The deprojection of axisymmetric density distributions is generally indeterminate to within the addition of certain axisymmetric distributions (konus densities) that are invisible…
Gravitational Lenses and the Structure of Galaxies
C. S. Kochanek
Nearly singular isothermal mass distributions with small core radii are consistent with stellar dynamics, lens statistics, and lens models as a model for E/S0 galaxies. Models like…
A Technical Memorandum On Core Radii In Lens Statistics
C. S. Kochanek
Quantitative estimates of lensing probabilities must be self-consistent. In particular, for asymptotically isothermal models: (1) using the correction for the velocit…
Preliminary Spectral Analysis of SN 1994I
E. Baron, P. H. Hauschildt, D. Branch +2
We present optical spectra of the Type Ic supernova 1994I in M51 and preliminary non-LTE analysis of the spectra. Our models are not inconsistent with the explosions of C+O cores o…
Detection of the Angular Correlation of Faint X-ray Sources
A. Vikhlinin, W. Forman
We have analyzed a set of deep ROSAT observations with a total sky coverage of 40 square degrees to search for clustering of faint X-ray sources. Using the resulting catalog of dis…
Advection-Dominated Models of Luminous Accreting Black Holes
Ramesh Narayan
It has been found that a class of optically-thin two-temperature advection-dominated accretion solutions explains many observations of low-luminosity accreting black holes. Here it…
Optical Detection of the Hidden Nuclear Engine in NGC~4258
Belinda J. Wilkes, Gary D. Schmidt, Paul S. Smith +2
The sub-parsec masing disk recently found to be orbiting a central mass of ~\msun\ in the Seyfert/LINER galaxy NGC~4258 provides the most compelling evidence to…
Higher-Order Gravitational Perturbations of the Cosmic Microwave Background
Ted Pyne, Sean M. Carroll
We study the behavior of light rays in perturbed Robertson-Walker cosmologies, calculating the redshift between an observer and the surface of last scattering to second order in th…
Models of Quiescent Black Hole Neutron Star Soft X-Ray Transients
Insu Yi, Ramesh Narayan, Didier Barret +1
When the mass accretion rate onto a black hole (BH) falls below a critical rate, , accretion can occur via a hot optically thin flow where m…
Nuclear spin--rotation interaction in the hydrogen molecular ion
James F. Babb
The nuclear spin--rotation interaction in the hyperfine structure of the hydrogen molecular ion is investigated. The interaction constants are determined and are found to differ in…
Intracluster Globular Clusters
Michael J. West, Patrick Cote, Christine Jones +2
Globular cluster populations of supergiant elliptical galaxies are known to vary widely, from extremely populous systems like that of UGC 9799, the centrally dominant galaxy in Abe…
A New Model for Black Hole Soft X-ray Transients in Quiescence
Ramesh Narayan, Jeffrey E. McClintock, Insu Yi
We present models of the soft X-ray transients, A0620-00, V404 Cyg, and X-ray Nova Mus 1991, in quiescence. In each source, we postulate that there is an outer region, extending ou…
Substructure: Clues to the Formation of Clusters of Galaxies
Michael J. West, Christine Jones, William Forman
We have examined the spatial distribution of substructure in clusters of galaxies using Einstein X-ray observations. Subclusters are found to have a markedly anisotropic distributi…
Weighing the Universe with the Cosmic Microwave Background
Gerard Jungman, Marc Kamionkowski, Arthur Kosowsky +1
Variations in , the total density of the Universe, leave a clear and distinctive imprint on the power spectrum of temperature fluctuations in the cosmic microwave background (CM…