Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- California Institute of TechnologyUS2.6k papers
- Centre National de la Recherche ScientifiqueFR2k papers
- Massachusetts Institute of TechnologyUS1.9k papers
- University of FloridaUS1.8k papers
- Carnegie Mellon UniversityUS1.7k papers
- Princeton UniversityUS1.7k papers
- University of RochesterUS1.7k papers
- Purdue University West LafayetteUS1.6k papers
- Johns Hopkins UniversityUS1.6k papers
- University of Maryland, College ParkUS1.6k papers
- The Ohio State UniversityUS1.6k papers
- University of California, Santa BarbaraUS1.6k papers
24 papers · 2 filters
Gas-Rich Dwarf Galaxies from the PSS-II --- II. Optical Properties
R. A. Pildis, J. M. Schombert, J. Eder
We describe the optical properties of a sample of 101 gas-rich field dwarf galaxies found on PSS-II (Second Palomar Sky Survey) plates, most newly discovered as part of a survey to…
Gas Rich Dwarfs from the PSS-II I. Catalog and Characteristics
James Schombert, Rachel Pildis, Jo Ann Eder
This project is a visual search for field dwarf galaxies using Second Palomar Sky Survey photographic plates. A morphologically selected sample of 310 objects yielded 145 detection…
The Tully-Fisher Relation and H_not
R. Giovanelli, M. Haynes, L. da Costa +3
The use of the Tully-Fisher (TF) relation for the determination of the Hubble Constant relies on the availability of an adequate template TF relation and of reliable primary distan…
Small-scale-field Dynamo
A. Gruzinov, S. Cowley, R. Sudan
Generation of magnetic field energy, without mean field generation, is studied. Isotropic mirror-symmetric turbulence of a conducting fluid amplifies the energy of small-scale magn…
NGC 4138 - A Case Study in Counterrotating Disk Formation
Aniruddha R. Thakar, Barbara S. Ryden, Katherine P. Jore +1
The Sa(r) galaxy NGC 4138 has been recently found to contain an extensive counterrotating disk which appears to be still forming. Up to a third of the stars in the disk system may…
The Mid-Infrared Color of NGC 6946
G. Helou, S. Malhotra, C. A. Beichman +10
We analyze the new mid-infrared maps of NGC 6946 for variations in the color ratio of the 7-to-15 micron emission. Our preliminary findings are that this mid-infrared color is rema…
ISOCAM Observations of NGC 6946: Mid-IR Structure
S. Malhotra, G. Helou, D. van Buren +12
The nearby spiral galaxy NGC 6946 was observed with ISO-CAM in the mid-infrared, achieving 7 arcsec resolution and sub-MJy/steradian sensitivity. Images taken with CAM filters LW2…
A Test of the Lauer--Postman Bulk Flow
Riccardo Giovanelli, Martha P. Haynes, Gary Wegner +3
We use Tully--Fisher distances for a sample of field late spiral galaxies to test the Lauer and Postman (1994; hereinafter LP) result suggestive of a bulk flow with respect to the…
Deviations from Hubble Flow in the Local Universe
Riccardo Giovanelli
Reviews observational situation in the measurement of peculiar velocities in the local universe. Emphasis is placed on such topics as: Do spirals and ellipticals yield the same pec…
The I-Band Tully-Fisher Relation for Cluster Galaxies: a Template Relation, its Scatter and Bias Corrections
R. Giovanelli, M. Haynes, T. Herter +5
Infrared I band photometry and velocity widths for galaxies in 24 clusters, with radial velocities between 1,000 and 10,000 \kms, are used to construct a template Tully--Fisher (TF…
The I-Band Tully-Fisher Relation for Cluster Galaxies: Data Presentation
R. Giovanelli, M. Haynes, T. Herter +5
Observational parameters which can be used for redshift-independent distance determination using the Tully-Fisher (TF) technique are given for 782 spiral galaxies in the fields of…
The I-Band Tully-Fisher Relation and the Hubble Constant
Riccardo Giovanelli
The application of the I band Tully--Fisher relation towards determining the Hubble constant is reviewed, with particular attention to the impact of scatter and bias corrections in…
The Relative Distance between the Clusters of Galaxies A2634 and Coma
Marco Scodeggio, Riccardo Giovanelli, Martha P. Haynes
The Tully-Fisher and Fundamental Plane relations are used to obtain two independent estimates of the relative distance between the clusters A2634 and Coma. Previously published stu…
Finding Radio Pulsars in and Beyond the Galactic Center
James M. Cordes, T. Joseph W. Lazio
Radio-wave scattering is enhanced dramatically for Galactic center sources in a region with radius >~ 15 arc min. Using scattering from Sgr A* and other sources, we show that pulse…
Density Fluctuations in the Galactic Halo and Experimental Searches for Dark Matter
Ira Wasserman
Clumping of elementary dark matter in the Galaxy halo may be inevitable. If so, the nondetection of certain dark matter candidates could simply mean that the local halo density is…
An adaptive hierarchical particle-mesh code with isolated boundary conditions
Sergio Gelato, David F. Chernoff, Ira Wasserman
This article describes a new, fully adaptive Particle-Multiple-Mesh numerical simulation code developed primarily for simulations of small regions (such as a group of galaxies) in…
The Mass Distribution in the Nearby Universe
Luiz N. da Costa, Wolfram Freudling, Gary Wegner +3
We present a new reconstruction of the mass density and the peculiar velocity fields in the nearby universe using recent measurements of Tully-Fisher distances for a sample of late…
The Magnetohydrodynamics of Supersonic Gas Clouds: MHD Cosmic Bullets and Wind-Swept Clumps
T. W. Jones, Dongsu Ryu, I. L. Tregillis
We report an extensive set of two-dimensional MHD simulations exploring the role and evolution of magnetic fields in the dynamics of supersonic plasma clumps. We examine the influe…
Orbital Parameters of the PSR B1620-26 Triple System
Z. Arzoumanian, K. Joshi, F. A. Rasio +1
Previous timing data for PSR~B162026 were consistent with a second companion mass anywhere in the range , i.e., from a Jupiter-type planet to a sta…
Two-Stream Instability of Counter-Rotating Galaxies
R. V. E. Lovelace, K. P. Jore, M. P. Haynes
The present study of the two-stream instability in stellar disks with counter-rotating components of stars and/or gas is stimulated by recently discovered counter-rotating spiral a…
Gamma-ray Flares and VLBI Outbursts of Blazars
M. M. Romanova, R. V. E. Lovelace
A model is developed for the time dependent electromagnetic - radio to gamma-ray - emission of active galactic nuclei, specifically, the blazars, based on the acceleration and crea…
Counter-rotating Accretion Disks
R. V. E. Lovelace, Tom Chou
We consider accretion disks consisting of counter-rotating gaseous components with an intervening shear layer. Configurations of this type may arise from the accretion of newly sup…
The Rotation Curves of Galaxies at Intermediate Redshift
Nicole P. Vogt, Terry Herter, Martha P. Haynes +1
We have undertaken a pilot project to measure the rotation velocities of spiral galaxies in the redshift range 0.18 < z < 0.4 using high dispersion long slit spectroscopy obtained…
Arecibo HI Mapping of a Large Sample of Dwarf Irregular Galaxies
G. L. Hoffman, E. E. Salpeter, B. Farhat +3
Neutral hydrogen mapping of 70 dwarf irregular (Sm, Im and BCD) galaxies is reported, with position-velocity contour maps presented for those resolved by the Arecibo beam. The gala…