Computer experiments for the scientific analysis

of data of the solar photosphere from observations and simulations

M. Schüssler, D. Schmitt, A. VöglerMax-Planck-Institut für Aeronomie

XLAB Science CampJuly 2003

• How does granulation appear in observations?• Correlation between brightness and vertical velocity• Granulation in a computer simulation and comparison with observation• Adaptation of the simulation results to the observational conditions • Interaction of convection and magnetic field in a simulation: correlation between magnetic field, brightness and velocity

Qualitative and quantitative descriptionof images of the solar photosphereand recognition of physical correlations

Qualitative description

Recognition of typical structures or patterns, typical sizes, comparison of various physical quantities

Quantitative descriptionby statistical methods

Mean value:

Standarddeviation:

Histogram:

Scatter plot:

Working with IDLIDL = Interactive Data LanguagePackage for the visualisation and analysis of data

Start with command „idl“, prompts with string IDL>

IDL> .r idlrc: initial settings

IDL> .r load: reads data sets i_obs, v_obs, i_sim, v_sim, ...

IDL> view,fn: displays a two-dimensional image, fn=i_obs, …

IDL> statistics,fn: computes mean value and standard deviation

IDL> histogram,fn: displays a histogram

IDL> scatter,fn1,fn2: scatter plot

IDL> smooth,fn: smoothes an image

IDL> exit

Please, write detailed notes of

your findings and results.

Have fun!