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Collapsars: Gamma-Ray Bursts and Explosions in “Failed Supernovae”
- A. Macfadyen, S. Woosley
- Physics
- 19 October 1998
Using a two-dimensional hydrodynamics code (PROMETHEUS), we explore the continued evolution of rotating helium stars, Mα ≳ 10 M☉, in which iron-core collapse does not produce a successful outgoing…
The afterglow of GRB 050709 and the nature of the short-hard γ-ray bursts
The final chapter in the long-standing mystery of the γ-ray bursts (GRBs) centres on the origin of the short-hard class of bursts, which are suspected on theoretical grounds to result from the…
The Binary Neutron Star Event LIGO/Virgo GW170817 160 Days after Merger: Synchrotron Emission across the Electromagnetic Spectrum
- R. Margutti, K. Alexander, J. Zrake
- Physics
- 10 January 2018
We report deep Chandra X-ray Observatory (CXO), Hubble Space Telescope (HST), and Karl J. Jansky Very Large Array (VLA) observations of the binary neutron star event GW170817 at t < 160 days after…
BINARY BLACK HOLE ACCRETION FROM A CIRCUMBINARY DISK: GAS DYNAMICS INSIDE THE CENTRAL CAVITY
- B. Farris, P. Duffell, A. Macfadyen, Z. Haiman
- Physics
- 1 October 2013
We present the results of two-dimensional (2D) hydrodynamical simulations of circumbinary disk accretion using the finite-volume code DISCO. This code solves the 2D viscous Navier–Stokes equations on…
A novel explosive process is required for the γ-ray burst GRB 060614
- A. Gal-yam, D. Fox, A. Macfadyen
- PhysicsNature
- 21 December 2006
Over the past decade, our physical understanding of γ-ray bursts (GRBs) has progressed rapidly, thanks to the discovery and observation of their long-lived afterglow emission. Long-duration (≳2 s)…
Supernovae, Jets, and Collapsars
- A. Macfadyen, S. Woosley, A. Heger
- Physics
- 2 October 1999
We continue our study of the possible production of supernovae and a variety of high-energy transients by black hole formation in massive stars endowed with rotation: the "collapsar model." The black…
An Eccentric Circumbinary Accretion Disk and the Detection of Binary Massive Black Holes
- A. Macfadyen, M. Milosavljevic
- Physics
- 20 July 2006
We present a two-dimensional grid-based hydrodynamic simulation of a thin, viscous, locally isothermal corotating disk orbiting an equal-mass Newtonian binary point mass on a fixed circular orbit. We…
Relativistic Jets in Collapsars
- Weiqun Zhang, S. Woosley, A. Macfadyen
- Physics
- 19 July 2002
We examine the propagation of two-dimensional relativistic jets through the stellar progenitor in the collapsar model for gamma-ray bursts (GRBs). Each jet is parameterized by a radius where it is…
RAM: A Relativistic Adaptive Mesh Refinement Hydrodynamics Code
- Weiqun Zhang, A. Macfadyen
- Physics
- 23 May 2005
We have developed a new computer code, RAM, to solve the conservative equations of special relativistic hydrodynamics (SRHD) using adaptive mesh refinement (AMR) on parallel computers. We have…
THE DYNAMICS AND AFTERGLOW RADIATION OF GAMMA-RAY BURSTS. I. CONSTANT DENSITY MEDIUM
- Weiqun Zhang, A. Macfadyen
- Physics
- 13 February 2009
Direct multidimensional numerical simulation is the most reliable approach for calculating the fluid dynamics and observational signatures of relativistic jets in gamma-ray bursts (GRBs). We present…
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