University Collaborators and Computing Systems
- University of Rochester, Computational Astrophysics Group
- Rice University, Laboratory Astrophysics Group
- STIC: 90 dual quad-core compute nodes with 12GB RAM per node (min. 1.5GB RAM per core).
- University of Minnesota, Computational Astrophysics Group
- University of North Carolina, Physics and Astronomy, Applied Mathematics
- kure: 122 dual quad-core nodes with 48 GB RAM per node (max. 6 GB RAM per core)
The following is a sample of projects involving or incorporating AstroBEAR. Many if not all of these projects are ongoing, so anyone interested in a particular project should contact the individual or group working on that project.
Newer projects are listed first.
- Exploring hierarchical gravitational collapse and the resulting "turbulence".
- Observing the effects of different background media on the critical Bonnor Ebert sphere.
- Exploring the structure and stability (hydrostatic, rotational, magnetic) of Bonner Ebert spheres, and the conditions that trigger their gravitational collapse.
- Studying star formation at the edge of colliding flows in large cloud formations. Exploring the effects of NTSI, thermal instability, and shear flows on star formation rates in these regions.
- Module Explanation
- Recent HST images of Herbig-Haro (HH) objects suggest that certain locations of bright emission are not indicative of high densities (i.e., radiating knots), but rather so-called Mach stems. These features can appear at the intersection between two oblique shocks, such as two close bow shocks. We seek to better understand this phenomenon through numerical investigation.
- While much work has been done studying the phenomenon of an astrophysical jet impinging on one or more clumps, less work has been devoted to the interaction of two clumps themselves. We therefore seek to extend previous work and investigate the morphological differences of, for example, a head-on collision versus an overtaking one.
- Cooling is known to be operative in many astrophysical environments. Recent HST observations suggest that regions close to Herbig-Haro (HH) objects may be turbulent. Since the emission in these regions comes from hot, shocked gas, radiative cooling also must play a role. We therefore are investigating the implications of cooling being operative in a turbulent environment.
- Despite the prevalence of radiative cooling in astrophysical systems, researchers including its effects in their studies may not consider its role in detail beyond a brief consideration of timescales. We therefore offer a systematic study based on the shocked-clump scenario. We discuss the regimes of cooling which may occur, depending on parameters, in which the bow shock and transmitted shock cool at varying speeds. We demonstrate that this variance has a great impact on the morphology and evolution of the clump as it is destroyed and mixed into the post-shock flow.
Turbulence in Molecular Clouds (Jonathan. University of Rochester)
- The dependence of turbulence on stellar jets is being investigated. One open-ended question concerns the apparent longevity of turbulence, namely, "Can jets impart sufficient kinetic energy to support the observed turbulence spectrum?"
Clumpy Jets (Kris. University of Rochester)
- Modelling Herbig-Haro objects which either display inherent "clumpyness" or become disrupted due to interaction with a "clumpy" medium.
Nested Winds (Martin. University of Rochester)
- Modelling two-wind interaction from planetary nebulae.
- Modelling multi-mode perturbation 3D Rayleigh-Taylor instability with ablation effects. The Linear System Solver was previously used to handle heat conduction/diffusion effects, and the nonlinear dependence on temperature is suitable for laboratory experiments. When HYPRE is fully integrated into AstroBEAR, it will handle the diffusion process.
- Studying inhomogeneous clumps in the interstellar medium, with embedded magnetic fields. Of particular interest are the interactions of these clumps when hit by supersonic shocks and winds.
- MHD Clump Test Home Page
- Studying the problem of shock triggered star formation.
Emission Line Images (Jacob. Rice University)
- A post-processing code for AstroBEAR that creates emission line images.
Cosmic Rays (Paul. University of Minnesota)
- Adding in cosmic ray diffusion and feedback to AstroBEAR. When completed the code will be used to investigate 2-D Diffusive Shock Acceleration in Stellar Winds and Supernova Remnants.
- Studying the instabilities of magnetized clumps and clouds in the interstellar medium. The clouds are usually filled by strong magnetic field with low beta.
- This work involves volume-filling spherical symmetric magnetic field configuration which is force free to maintain the initial equilibrium. Later, various physics processes such as self gravity and anisotropic diffusion could be added to the situation.
- Studying the shocked behavior of magnetized clumps and clouds in the interstellar medium. The clouds are usually filled by strong magnetic field with low beta.
- This work involves volume-filling spherical symmetric magnetic field configuration which is force free to maintain the initial equilibrium. We also study the effect of background fields and various physics processes such as thermal conduction.
- Studying the tidal disruption of stellar objects around intermediate and massive black holes.
- Documenting the multiphysics functionality in AstroBEAR.
- Testing the resistive MHD functionality.
Wind Disk Interactions (Martin et al…)
- Studying the effects of stellar winds on companion disks.
3D Cooling Jets (Eddie et al…)
- Studying the effects of strong cooling on jets. Simulations run in 2D, 2.5D, and 3D.
Shock Triggered Star Formation (Shule Li et al…)
- Studying the triggering event of an otherwise stable cloud from a supernova shock.
AstroBEAR GPU (Shule Li)
- In this project, we implement and benchmark the AstroBEAR solvers on GPU.