Numerical simulation of waves

Background

Acoustic waves are naturally occuring in stellar atmospheres. They can be excited by specific events but they are also continuously excited by stochastic motions in the convection zone. Because of the density exponentially decreasing with height, waves will get increased amplitude when travelling upwards and will eventually shock. RADYN was originally written to study these waves and shocks (Carlsson & Stein 1992, 1995, 1997).

Goal

The goal of this project is to simulate acoustic waves travelling through the atmosphere and look at the signatures in lines that can be observed with the Swedish 1-m Solar Telescope (SST).

Method

 

1. Use an existing starting model similar to VAL3C.

 

 

Use atmdyn.val3c and param.he_flare_em from the radyn/input directory but switch off the beam heating and switch on waves

 

2. Run with various wave parameters.

 

 

Vary amp and period. Proper ranges are amp=[0.01,0.1], period=[10,300]

Look at the atmosphere response and explain through an analysis of the terms in the energy equation (using emovie)

3. Study diagnostics.

 

 

Especially diagnostics available at SST (could be extended to include IRIS diagnostics).