Search
Now showing items 1-10 of 15
Equivalence Principle Implications of Modified Gravity Models
(American Physical Society, 2009)
Theories that attempt to explain the observed cosmic acceleration by modifying general relativity all introduce a new scalar degree of freedom that is active on large scales, but is screened on small scales to match ...
Linking Optical and Infrared Observations with Gravitational Wave Sources Through Variability
(Institute of Physics, 2008)
Optical and infrared observations have thus far detected more celestial cataclysms than have been seen in gravity waves (GW). This argues that we should search for gravity wave signatures that correspond to flux variability ...
Solar System Constraints on the Dvali-Gabadadze-Porrati Braneworld Theory of Gravity
(American Physical Society, 2008)
A number of proposals have been put forward to account for the observed accelerating expansion of the Universe through modifications of gravity. One specific scenario, Dvali-Gabadadze-Porrati (DGP) gravity, gives rise to ...
Dark-Matter-Induced Weak Equivalence Principle Violation
(American Physical Society, 2009)
A long-range fifth force coupled to dark matter can induce a coupling to ordinary matter if the dark matter interacts with Standard Model fields. We consider constraints on such a scenario from both astrophysical observations ...
The Geometry of and Mass Accretion Rate through the Maser Accretion Disk in NGC 4258
(IOP Publishing, 2005)
A maximum likelihood analysis of the NGC 4258 maser positions and velocities reveals a ∼ 2 σ deviation from Keplerian motion in the projected rotation curve of the high-velocity features, corresponding to a ∼ 9 km s−1, or ...
Evidence for a Geometrically Thick Self‐Gravitating Accretion Disk in NGC 3079
(IOP Publishing, 2005)
We have mapped, for the first time, the full velocity extent of the water maser emission in NGC 3079. The largely north-south distribution of emission, aligned with a kpc-scale molecular disk, and the segregation of blue- ...
Line Imaging of Orion KL at 865 μm with the Submillimeter Array
(IOP Publishing, 2005)
We present the first submm (865 µm) imaging spectral line survey at one arcsecond resolution conducted with the Submillimeter Array toward Orion-KL. Within the two × two GHz bandpasses (lower and upper sidebands, 337.2–339.2GHz ...
A Search for H 2 O Maser Emission in Southern Active Galactic Nuclei and Star‐forming Galaxies: Discovery of a Maser in the Edge‐on Galaxy IRAS F01063?8034
(IOP Publishing, 2002)
We report the cumulative results of five surveys for H2O maser emission at 1.35 cm wavelength in 131 active galactic nuclei (AGNs) and star-forming galaxies, conducted at the Parkes Observatory between 1993 and 1998. We ...
Atmospheric Phase Correction Using Total Power Radiometry at the Submillimeter Array
(IOP Publishing, 2004)
Phase noise caused by an inhomogeneous, time-variable water vapor distribution in our atmosphere reduces the angular resolution, visibility amplitude and coherence time of millimeter and submillimeter wavelength interferometers. ...
A Warped Accretion Disk and Wide‐Angle Outflow in the Inner Parsec of the Circinus Galaxy
(IOP Publishing, 2003)
We present the first VLBI maps of H2O maser emission (λ1.3 cm) in the nucleus of the Circinus Galaxy, constructed from data obtained with the Australia Telescope Long Baseline Array. The maser emission traces a warped, ...