Wave propagation in the upper convection zone

Robert CameronLaurent Gizon

Max Planck Institute for Solar System Research

Outline

The photosphere The wave code Sunspots

Regimes of solar

magneto-convection

G-band image: KIS/VTT, Obs. del Teide, Tenerife

sunspot

plage

‘quiet’ Sun

poreLocal structuring -quiet Sun -plage -umbral dots

Global structuring-pores-sunspots-flux emergence

Linear, ideal equations

Currently no background flows are allowed.

BCs and IC

Upper BC: vertical components of shear stress tensor vanishes

Lower: perturbation vanishes Sides: periodic

IC: arbitrary, but eg right moving f-mode wave packet.

Numerical scheme

Spectral (fourier) in the horizontal directions. Uses FFTW. Finite difference (2-step Lax-Wendroff) in the

Vertical (This will probably change soon.)

Status: preliminary results, some test cases.

We will (at some point) provide

Wave code Sample background

You will need to make your own interesting atmospheres. (Possibly eg using fully non-linear backgrounds from Stein and Nordlund).

Sunspot models

From Rempel and Schüssler

Preliminary Simulation

Observations from Gizon

Working on

Background velocities.

Top BC

Extending the atmosphere upwards

What to do with high Alfven velocities

Quiet Sun simulations

MURaM Quiet sun granulation box extended upwards with Model S atmosphere.

HELAS

Wants to collect and make available modeling tools.

What type of tools are interesting? (Please discuss this afternoon and not during my question time.)

Working (essential) and documented (please?).

Maintenance is probably unreasonable, but perhaps we should have a users (where should the apostrophe go?) blog for each tool?