John F. Hawley, Professor
- Phone: (434) 924-4901
- Main office: (434) 924-7494
- Fax: (434) 924-3104
- PO Box 400325, University of Virginia
Charlottesville, VA 22904-4325
- Chair, Department of Astronomy, 2006-
University of Virginia
- Professor, 1999-
- Assistant Professor, 1987-93
- Associate Professor, 1993-99
- Ph.D. 1984,
University of Illinois
- Bantrell Fellow, 1984-87,
California Inst. of Technology
- Recipient, 1993 Helen B. Warner Prize, American Astronomical Society
In the spring semester I teach
Introduction to Cosmology. The home pages for these courses
provide a brief preview of their content.
The cosmology course uses my textbook
Foundations of Modern Cosmology which is published by
Oxford University Press.
My research activities have primarily been concerned with accretion
disks and related phenomena. I have chosen to focus on the basic
physics of such systems through the use of computational
finite-difference techniques. This approach necessitates the
development of numerical algorithms, and the devotion of considerable
effort to programming, computation, and visualization. Pictured here
is an an image from a three dimensional simulation of a magnetized
Some past papers on numerical algorithms include
- J. F. Hawley, L. L. Smarr, and J. R. Wilson, ``A Numerical Study of
Black Hole Accretion: II. Finite Differencing and Code Calibration,''
Astrophys. J. Supp., 55, 211 (1984).
- C. R. Evans and J. F. Hawley, ``Simulation of General
Relativistic Magnetohydrodynamic Flows: A Constrained Transport
Method,'' Astrophys. J. 332, 659 (1988).
- J. M. Stone, J. F. Hawley, C. R. Evans, M. L. Norman,
``A Test Suite for Magnetohydrodynamic Simulations''
(1992) Astrophysical Journal, , 388, 415-437.
- E. A. Lufkin and J. F. Hawley, ``PLPC: A Lagrangian-Remap
Method for Astrophysical Flows,'' (1993) Astrophysical J. Supp.,
- J. F. Hawley, and J. M. Stone, ``MOCCT: A Numerical
Technique for Astrophysical MHD,'' (1995) Comp. Phys. Comm.,
89, 127 (1995).
A good deal of my current research is concerned with the behavior of
gas in orbit around compact stars and black holes, particularly on the
stability properties of accretion disks. For example, recent
simulations have investigated
the generation of magnetohydrodynamical turbulence in disks and
the resulting angular momentum transport. This turbulence arises from
the presence of a weak magnetic field instability in accretion disks.
The paper that describes the magnetorotational instability is
S. A. Balbus and J. F. Hawley, ``A Powerful Local Shear
Instability in Weakly Magnetized Disks: I. Linear Analysis,''
Astrophys. J., 376, 214 (1991).
Disk review papers include:
- J. F. Hawley, ``Keplerian Complexity: Numerical
Simulations of Accretion Disk Transport,'' Science, 269,
- S. A. Balbus and J. F. Hawley, "Instability, Turbulence, and
Enhanced Transport in Accretion Disks," Reviews of Modern Physics,
70, 1 (1998)
- Hawley, J. F. and Balbus, S. A. 1999, ``Transport in Accretion
Disks,'' Phys. Plasmas, 6, No. 12, 4444-4449.
Disk Simulations on the Web
Here are recent papers on global accretion disk simulations:
The Dynamical Structure of Nonradiative Accretion Flows
Astrophysical Journal, 573, 749 (2002).
The web version of this paper provides MPEG animations.
High Resolution Simulations of the Plunging Region in a
Pseudo-Newtonian Potential: Dependence on Numerical Resolution
and Field Topology
Astrophysical Journal, 566, 164 (2002).
The web version of this paper also provides MPEG animations.
A Magnetohydrodynamic Nonradiative Accretion
Flow in Three Dimensions
Astrophysical Journal Letters, 554, (2001)
The preprint is on the web along with
a MPEG animations, and a color version of figure 1.
Global MHD Simulations of Cylindrical
Keplerian Disks. Astrophysical
Journal, 554, 534 (2001). The preprint is on the web along with
MPEG animations of the simulations.
Global MHD Simulation of the Inner
Accretion Disk in a Pseudo-Newtonian Potential.
Astrophysical Journal, 548, 348 (2001).
The web version of this paper includes MPEG animations of the simulation.
Global Magnetohydrodynamical Simulations of Accretion Tori
Astrophysical Journal, 528, 462 (2000).
The web version of this paper also provides MPEG animations.
Other Disk Simulations
This image shows a cross section through a magnetized
disk in which the magnetorotational instability has created
turbulence. The blue indicates gas with less than Keplerian angular
momentum; the red is gas with excess angular momentum. The MHD
instability is very effective at creating the angular momentum
transport required to make accretion disks accrete.
This is from the two dimensional simulations described in
- J. F. Hawley and S. A. Balbus, ``A Powerful Local Shear
Instability in Weakly Magnetized Disks: III. Long Term Evolution in a
Shearing Sheet,'' (1992) Astrophysical Journal, 400,
This image shows the
density distribution from a three-dimensional MHD
simulation of a small portion of a stratified accretion disk.
This disk is threaded with an weak toroidal magnetic field. A
2 MB MPEG movie shows the development
and evolution of angular momentum perturbations in this disk.
More about simulations of this type can be found in
Stone, J.M, Hawley, J.F., Gammie, C.F., and Balbus, S.A.,
``Three-Dimensional Magnetohydrodynamical Simulations of Vertically
Stratified Accretion Disks,'' (1996) Astrophysical Journal,
Papers on the local hydrodynamic stability of differential rotation:
- Balbus, S.A., Hawley, J.F., and Stone, J.M.,
``Nonlinear Stability, Hydrodynamic Turbulence, and Transport in
Disks,'' Astrophys. J., 467, 76 (1996).
- Hawley, J. F., Balbus, S. A., and Winters, W. F. 1999,
``Local Hydrodynamic Stability of Accretion Disks,''
Astrophysical Journal, 518, 394-404.
Local MHD shearing box simulations:
- Hawley, J.F., Gammie, C.F., & Balbus, S.A., ``Local
Three Dimensional Magnetohydrodynamic Simulations of Accretion
Disks,'' (1995) Astrophysical Journal, 440, 742
- J. F. Hawley, Gammie, C.F., and Balbus, S.A., ``Local
Three Dimensional Simulations of an Accretion Disk Dynamo,''
Astrophysical Journal , 464, 690 (1996)
- Hawley, J. F. and Stone, J. M. 1998, ``Nonlinear Evolution
of the Magnetorotational Instability in Ion-Neutral Disks,''
Astrophysical Journal , 501, 758-771
- Fleming, T. P., Stone, J. M., and Hawley, J. F. 2000, ``The
Effect of Resistivity on the Nonlinear Stage of the Magnetorotational
Instability in Accretion Disks,'' Astrophysical Journal ,
Global Three Dimensional accretion disk simulations:
- J.F. Hawley, "Global Magnetohydrodynamical Simulations of
Accretion Tori,'' ApJ, 528, 462 (2000).
- J. F. Hawley and J. H. Krolik,
``Global MHD Simulation of the Inner
Accretion Disk in a Pseudo-Newtonian Potential''
Astrophysical Journal, 548, 348 (2001)
- Hawley, J. F., ``Global Magnetohydrodynamical
Simulations of Cylindrical Keplerian Disks,'' ApJ, 554,
- Hawley, J. F., Balbus, S. A., & Stone, J. M. 2001, ``A
Magnetohydrodynamic Nonradiative Accretion Flow in Three Dimensions,''
ApJ Lett, 554, (2001)