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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…
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…
OFF-AXIS GAMMA-RAY BURST AFTERGLOW MODELING BASED ON A TWO-DIMENSIONAL AXISYMMETRIC HYDRODYNAMICS SIMULATION
- H. van Eerten, Weiqun Zhang, A. Macfadyen
- Physics
- 26 June 2010
Starting as highly relativistic collimated jets, gamma-ray burst outflows gradually slow down and become nonrelativistic spherical blast waves. Although detailed analytical solutions describing the…
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