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astro-ph2008★ 3 cited

NuGrid: Toward High Precision Double-Degenerate Merger Simulations with SPH in 3D

Steven Diehl, Christopher L. Fryer, Aimee Hungerford +11

We present preliminary results from recent high-resolution double-degenerate merger simulations with the Smooth Particle Hydrodynamics (SPH) technique. We put particular emphasis o…

astro-ph2008★ 28 cited

An anti-correlation between X-ray luminosity and H-alpha equivalent width in X-ray binaries

R. P. Fender, D. M. Russell, C. Knigge +3

We report an anticorrelation between continuum luminosity and the equivalent width (EW) of the H-alpha emission line in X-ray binary systems. The effect is evident both in a univer…

astro-ph2008★ 33 cited

A dense disk of dust around the born-again Sakurai's object

Olivier Chesneau, G. C. Clayton, F. Lykou +7

In 1996, Sakurai's object (V4334 Sgr) suddenly brightened in the centre of a faint Planetary Nebula (PN). This very rare event was interpreted as the reignition of a hot white dwar…

astro-ph2008★ 46 cited

The Dust-to-Gas Ratio in the Small Magellanic Cloud Tail

K. D. Gordon, C. Bot, E. Muller +21

The Tail region of the Small Magellanic Cloud (SMC) was imaged using the MIPS instrument on the Spitzer Space Telescope as part of the SAGE-SMC Spitzer Legacy. Diffuse infrared emi…

astro-ph2008★ 203 cited

Beyond ideal MHD: towards a more realistic modeling of relativistic astrophysical plasmas

Carlos Palenzuela, Luis Lehner, Oscar Reula +1

Many astrophysical processes involving magnetic fields and quasi-stationary processes are well described when assuming the fluid as a perfect conductor. For these systems, the idea…

astro-ph2008★ 22 cited

The Diverse Solar Phase Curves of Distant Icy Bodies. II. The Cause of the Opposition Surges and Their Correlations

Bradley E. Schaefer, David L. Rabinowitz, Suzanne W. Tourtellotte

We collect well-measured opposition surge properties for many icy bodies orbiting the Sun (mostly from our own observations) plus for many icy moons, resulting in a data base of su…

astro-ph2008★ 25 cited

Does The Addition of a Duration Improve the L_iso - E_peak Relation For Gamma-Ray Bursts?

Andrew C. Collazzi, Bradley E. Schaefer

Firmani et al. proposed a new Gamma Ray Burst (GRB) luminosity relation that showed a significant improvement over the L_iso-E_peak relation. The new proposed relation simply modif…

astro-ph2008★ 116 cited

Search for Gravitational Wave Bursts from Soft Gamma Repeaters

LIGO Scientific Collaboration, S. Barthelmy, N. Gehrels +2

We present the results of a LIGO search for short-duration gravitational waves (GWs) associated with Soft Gamma Repeater (SGR) bursts. This is the first search sensitive to neutron…

astro-ph2008★ 154 cited

Galactic Globular and Open Clusters in the Sloan Digital Sky Survey. I. Crowded Field Photometry and Cluster Fiducial Sequences in ugriz

Deokkeun An, Jennifer A. Johnson, James L. Clem +22

We present photometry for globular and open cluster stars observed with the Sloan Digital Sky Survey (SDSS). In order to exploit over 100 million stellar objects with r < 22.5 mag…

astro-ph2008★ 635 cited

Observation of the suppression of the flux of cosmic rays above 4x10^19eV

The Pierre Auger Collaboration

The energy spectrum of cosmic rays above 2.5x10^18eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the flux, J ~ E…

astro-ph2008★ 63 cited

Relativistic simulations of the phase-transition-induced collapse of neutron stars

E. B. Abdikamalov, H. Dimmelmeier, L. Rezzolla +1

An increase in the central density of a neutron star may trigger a phase transition from hadronic matter to deconfined quark matter in the core, causing it to collapse to a more co…

astro-ph2008

Baroclinic Generation of Potential Vorticity in an Embedded Planet-Disk System

Ji Jianghui, Ou Shangli, Liu Lin

We use a multi-dimensional hydrodynamics code to study the gravitational interaction between an embedded planet and a protoplanetary disk with emphasis on the generation of vortens…

astro-ph2008★ 16 cited

Pluto's Light Curve in 1933-1934

Bradley E. Schaefer, Marc W. Buie, Luke Timothy Smith

We are reporting on a new accurate photographic light curve of Pluto for 1933-1934 when the heliocentric distance was 40 AU. We used 43 B-band and V-band images of Pluto on 32 plat…

astro-ph2008★ 216 cited

Beating the spin-down limit on gravitational wave emission from the Crab pulsar

The LIGO Scientific Collaboration, B. Abbott, R. Abbott +440

We present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first nine months of the fifth science run of the Laser Interferometer Gravit…

astro-ph2008★ 1.6k cited

Improved Cosmological Constraints from New, Old and Combined Supernova Datasets

M. Kowalski, D. Rubin, G. Aldering +67

We present a new compilation of Type Ia supernovae (SNe Ia), a new dataset of low-redshift nearby-Hubble-flow SNe and new analysis procedures to work with these heterogeneous compi…

astro-ph2008★ 44 cited

The Youthful Appearance of the 2003 EL61 Collisional Family

David L. Rabinowitz, Bradley E. Schaefer, Martha W. Schaefer +1

We present new solar phase curve observations of the 2003 EL61 collisional family showing that all the members have light-scattering properties similar to the bright icy satellites…

astro-ph2008★ 11 cited

Nereid: Light Curve for 1999-2006 and a Scenario for its Variations

Bradley E. Schaefer, Suzanne W. Tourtellotte, David L. Rabinowitz +1

Nereid is a small irregular moon of Neptune that displays large-, moderate-, and small-amplitude photometric variations on both fast and slow time scales. The central mystery of Ne…

astro-ph2008

Optical and UV Light Curves of the Accretion Disk Corona Source 4U 1822-371

A. J. Bayless, E. L. Robinson, R. I. Hynes +2

The eclipsing low-mass X-ray binary 4U is the prototypical accretion disk corona (ADC) system. We have obtained new time-resolved UV spectrograms of 4U with the Hubble Space Telesc…

astro-ph2008★ 212 cited

Upper limit on the cosmic-ray photon flux above 10^19 eV using the surface detector of the Pierre Auger Observatory

The Pierre Auger Collaboration

A method is developed to search for air showers initiated by photons using data recorded by the surface detector of the Auger Observatory. The approach is based on observables sens…

astro-ph2008★ 18 cited

An Overview of the Bowen Survey; detecting donor star signatures in Low Mass X-ray Binaries

Remon Cornelisse, Jorge Casares, Teo Munoz-Darias +4

In this paper we give a review of the Bowen fluorescence survey, showing that narrow emission lines (mainly NIII and CIII lines between 4630 and 4660 A) appear to be universally pr…

astro-ph2008★ 14 cited

Constraint preserving boundary conditions for the Ideal Newtonian MHD equations

Mariana Cecere, Luis Lehner, Oscar Reula

We study and develop constraint preserving boundary conditions for the Newtonian magnetohydrodynamic equations and analyze the behavior of the numerical solution upon considering d…

astro-ph2007★ 45 cited

Multi-patch methods in general relativistic astrophysics - I. Hydrodynamical flows on fixed backgrounds

Burkhard Zink, Erik Schnetter, Manuel Tiglio

Many systems of interest in general relativistic astrophysics, including neutron stars, accreting compact objects in X-ray binaries and active galactic nuclei, core collapse, and c…

astro-ph2007★ 374 cited

Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei

The Pierre Auger Collaboration

Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest energies, which are correlated with the…

astro-ph2007★ 172 cited

Upper limit on the diffuse flux of UHE tau neutrinos from the Pierre Auger Observatory

The Pierre Auger Collaboration

The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau-neutrinos that interact in the Earth's crust. Tau leptons from charged-cur…