Institute for Computational Astrophysics

PROGRAM ICA_CODES


AstroCodeImage
Code segment compliments of Michael Gruberbauer


SUBROUTINE ZEUS_FAMILY

Adaptive mesh refinement (AMR) magnetohydrodynamics (MHD)

ICA supported code: AZEuS
Purpose: Solves the time-dependent equations of MHD using adaptive temporal and spatial resolution
Principle authors: David Clarke and J. P. Ramsey (Institute for Computational Astrophysics)
ICA contact: D. A. Clarke
Language: FORTRAN; managed by the EDITOR preprocessor
Parallelized: OpenMP

Special features: The same feature set as ZEUS-3D, plus AMR modified for a fully-staggered mesh.

Availability: Will be made publicly available via the AZEuS website in the near future.  Subject to a limited set of conditions of use, anyone will be able to download and use the ICA-version of AZEuS.

Self-gravitating magnetohydrodynamics (MHD)

ICA supported code: ZEUS-3D
Purpose: Solves the time-dependent equations of (two-fluid) MHD
Principle authors: David Clarke (Institute for Computational Astrophysics)
ICA contact: D. Clarke
Language: FORTRAN; managed by the EDITOR preprocessor (included with the download)
Parallelized: OpenMP; FPP (Cray UNICOS)

Special features: Equations solved in 1-, 2-, or 3-D in a variety of geometries starting from user-supplied initial conditions and using user-supplied/specified boundary conditions. The user may supply additional physics. Other features: self-gravity, second fluid may be diffusive, cooling via Raga cooling tables, extensive suite of initial conditions and test problems, adiabatic or isothermal equation of state, energy conservative or positive-definite pressure, uses the CMoC algorithm (Clarke, 1996, ApJ,457, 291) for solving the induction equation.

Availability: Subject to a limited set of conditions of use, anyone can download and use the ICA-version of ZEUS3D from the ZEUS-3D web page . There is no technical help per se, although extensive installation and usage instructions come with the download. In addition, a ZEUS-3D "chat-room" is accessible from the page.

Future development: AMR (adaptive mesh refinement) version of ZEUS-3D: AZEuS (Adaptive Zone, Eulerian Scheme).
Release date: TBA.

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SUBROUTINE STELLAR_ATMOSPHERES

Stellar Atmospheres & Spectrum Synthesis

ICA supported code: PHOENIX
Purpose: Modeling of stellar atmospheres and spectra
Principle authors: P. H. Hauschildt (Hamburg Observatory), F. Allard (Centre de Recherche Astronomique de Lyon), E. Baron (University of Oklahoma)
ICA contact: C. I. Short
Language: FORTRAN 95, C
Parallelized: Yes; MPI, distributed memory architecture

Special features: Opacity of ~10^8 atomic and molecular lines for late-type stars, Dust and polyatomic molecules in opacity and EOS for brown dwarfs, relativistically expanding atmospheres for novae and supernovae, ~10^5 lines in direct multi-level NLTE

ICA supported code: Atlas9
Purpose: Modelling of stellar atmospheres and spectra
Principle authors: R. L. Kurucz (Harvard Smithsonian Center for Astrophysics)
ICA contact: C. I. Short
Language: FORTRAN
Parallelized: No.

Special features: Opacity of ~10^8 atomic and molecular lines for late-type stars

ICA supported code: Multi
Purpose: Modeling of spectral lines in Non-local thermodynamic equilibrium
Principle authors: M. Carlsson (Uppsala Observatory)
ICA contact: C. I. Short
Language: FORTRAN
Parallelized: No

Special features: Moving atmospheres for expanding, contracting, pulsating stars; multi-level NLTE

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SUBROUTINE ROTATION_FAMILY

Oscillation of Rotating Stars

ICA supported code: NRO
Purpose: Compute Oscillation Frequencies of Rotating Stars
Principle authors: Maurice Clement (University of Toronto, retired)
ICA contact: R. G. Deupree
Language: FORTRAN, C
Parallelized: No

Special features: This code solves for the linear, adiabatic pulsation frequencies and eigenfunctions given a 2D stellar model as input. Instead of the usual assumption of a single spherical harmonic for the latitudinal variation of a given mode, the code allows the latitudinal variation to be determined by a sum of spherical harmonics, the number of which is specified by the user.

Structure and Hydrodynamics of Rotating Stars

ICA Supported Code: ROTORC
Purpose: Compute the 2D structure and evolution of rotating stars, including following secular and    hydrodynamic instabilities
Principal Authors: R. G. Deupree
ICA Contact: R. G. Deupree
Language: FORTRAN
Parallelized: No

Special Features: This code computes the 2D structure and/or evolution of rotating stars. All the velocity terms are included so the code can compute hydrodynamics arising from (2D) instabilities to follow the redistribution of composition and angular momentum. The evolution can occur on either typical hydrodynamic or secular time scales.

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SUBROUTINE NON-LINEAR_RADIAL_PULSATIONS

Multi-dimensional Convection & Radial Pulsation

ICA supported code: SPHERLS (This link is currently unavailable.  It will be updated in the near future)
Purpose: To simulate the time evolution of convective motions in full amplitude radially pulsating stars in 2D and 3D. It can also simulate the time evolution of fully radiative 1D models.
Principle authors: Chris Geroux with guidance from R.G. Deupree (Institute for Computational Astrophysics)
ICA contact: C. Geroux
Language:  C++, with Python analysis scripts and matplotlib plotting
Parallelized: OpenMPI

Special features: The code has a 1D region towards center of star, and 1D, 2D or 3D region nearer surface. It uses the diffusion approximation for the radiative flux.  The three conservation equations (mass, vector momentum, and energy) explicitly except at the surface where it integrates the energy equation implicitly. The physical input includes up-to-date OPAL equations of state and opacities.

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SUBROUTINE_SPHERICAL_STARS

Spherical Stellar Evolution

ICA supported code: YREC (Yale Rotating Evolution Code)
Purpose: Compute stellar evolution sequences
Principal Authors: Pierre Demarque (Yale), David Guenther (SMU)
ICA contact: David Guenther
Language: Fortran
Parallelized: No
Special features: A detailed description of the code can be found in Demarque, P., Guenther, D. B., Li, L. H., Maxumdar, A., Straka, W. S. 2008, "YREC: The Yale Rotating Stellar Evolution Code," Astrophysics and Space Science, 316, 31-41.

Linear, Nonradial, Nonadiabatic Oscillations

ICA supported code: JIG
Purpose: Compute nonradial, nonadiabatic stellar pulsations
Principal Authors: David Guenther (SMU)
ICA contact: David Guenther
Language: Fortran
Parallelized: No
Special features: A detailed description can be found in Guenther, D. B. 1994, “Nonadiabatic Nonradial P-Mode Frequencies of the Standard Solar Model, With and Without Helium Diffusion,” ApJ, 442, 400-411.

Matching Theory to Data

ICA supported code: pmodesearch
Purpose: Search dense grids of seismic data to find best fit to observed spectrum
Principal Authors: David Guenther (SMU)
ICA contact: David Guenther
Language: Fortran
Parallelized: No
Special features: An overview of the code is described in Guenther, D. B., 2004, “Quantitative Analysis of the Oscillation Spectrum of η Boo,” ApJ, 612, 454-462.

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