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Computer experiments
for the scientific analysis
of data of the solar photosphere
from observations and simulations
M. Schüssler, D. Schmitt, A. Vögler
Max-Planck-Institut für Aeronomie
XLAB Science Camp
July 2003
Qualitative and quantitative description
of images of the solar photosphere
and recognition of physical correlations
• 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 description
Recognition of typical structures or patterns, typical
sizes, comparison of various physical quantities
Quantitative description
by statistical methods
Mean value:
Standard
deviation:
Histogram:
Scatter plot:
Working with IDL
IDL = Interactive Data Language
Package 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!