MHD Modeling of the Large Scale Solar Corona & Progress Toward Coupling with the Heliospheric

Model

Goals• To model physical processes from above

the transition region to the inner heliosphere (approximately 1 – 20 RS).

• The model will provide density, temperature, plasma velocity and magnetic field within this region.

• Couple the model to ENLIL (Dusan’s heliosphere code) in order to drive solar wind conditions at 1 AU.

Ultimate Goal of the Coronal MHD Modeling

• To input a synoptic map (Magnetic field in the photosphere) into the model and get out realistic coronal and solar wind parameters– Density

– Temperature

– Velocity

– Magnetic field structure

• Note this included active region scales and their effects on the global scale.

The Physical Process in the Corona are not well understood

• Heating Processes– What heats the coronal plasma? – How is the heating distributed?

• Wind Acceleration– How is the high speed solar wind accelerated.

• The lower boundary conditions are not well defined. – The same boundary issues that occur when

modeling a active region applies here.

McComas et al., 1998

Tools

• Static mesh MHD model (modified version of Zeus-3D) for testing and development.

• A Spherically Adaptive Mesh MHD model (ZeusAMR) for the global simulations.

• 3D MHD model (Enlil) for global heliospheric simulations (up to 5 AU).

Tool Status

• Static Mesh Model– Runs relatively quickly (depending on res.)– Includes Alfvén wave wind acceleration and

heating.– Work in progress includes:

• Adding or trying to parameterize radiative losses, collisionless and Spitzer conductivities.

• Incorporating synoptic maps to provide lower boundary conditions on the magnetic field.

Alfvén Wave Driven Wind Speeds in a Dipole Field Configuration

Spherical ZeusAMR Model

• Under development.• Currently working axisymmetric wedge

shaped domains (Cartesian version of ZeusAMR is working).

• Parallelization is underway.• The groundwork needed to couple the

model to the ENLIL heliosphere model has been incorporated.

Including Active Region Effects in the Global Corona. ZeusAMR Coronal model, initialized with PFSS model of CR1918.

Synthetic White-Light Imaging

Conclusions

• Development of the Coronal MHD model is well underway.

• We plan to have a coupled Coronal-Heliospheric MHD simulation by early summer.

• Future plans include coupling the global coronal model to data driven MHD models of active regions (Abbett).