517 citations · 12.3k across the 161 of their papers we have counts for
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MHD simulations of the collapsar model for GRBs
D. Proga, A. I. MacFadyen, P. J. Armitage +1
We present results from axisymmetric, time-dependent magnetohydrodynamic (MHD) simulations of the collapsar model for gamma-ray bursts. Our main conclusion is that, within the coll…
Substellar companions and isolated planetary mass objects from protostellar disc fragmentation
W. K. M. Rice, P. J. Armitage, I. A. Bonnell +3
Self-gravitating protostellar discs are unstable to fragmentation if the gas can cool on a time scale that is short compared to the orbital period. We use a combination of hydrodyn…
On the formation time scale and core masses of gas giant planets
W. K. M. Rice, Philip J. Armitage
Numerical simulations show that the migration of growing planetary cores may be dominated by turbulent fluctuations in the protoplanetary disk, rather than by any mean property of…
Migration of extrasolar planets to large orbital radii
Dimitri Veras, Philip J. Armitage
Observations of structure in circumstellar debris discs provide circumstantial evidence for the presence of massive planets at large (several tens of au) orbital radii, where the t…
Axisymmetric MHD simulations of the collapsar model for gamma-ray bursts
D. Proga, A. I. MacFadyen, P. J. Armitage +1
We present results from axisymmetric, time-dependent magnetohydrodynamic (MHD) simulations of the collapsar model for gamma-ray bursts. We begin the simulations after the 1.7 MSUN…
On the stability of self-gravitating protoplanetary discs
W. K. M. Rice, P. J. Armitage, I. A. Bonnell +1
It has already been shown, using a local model, that accretion discs with cooling times t_cool <= 3 Omega^-1 fragment into gravitationally bound objects, while those with cooling t…