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title: Measurements of Isat fluctuations
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#Motivation
Remember the good old days when theory predicted that tokamak confinement was absolutely fantastic? You probably don't, it was a very long time ago. Since then, we've seen evidence that plasma confinement in tokamaks is, sadly, deteriorated by several processes - and edge turbulence is one of them. Why is the edge turbulent? Where is the turbulence strongest? How does the turbulence look in single-probe measurements? You'll find out in this task!

#Task outline

* Learn about turbulence in tokamaks: why, where, and why it matters to us so much
* Get acquainted with probe measurements (Langmuir probe theory & real probes on GOLEM)
* Perform experiments with the rake probe
    * Pins in the $I_{sat}$ regime, we measure density and temperature spikes = turbulence
* Interpret the data using Python (or any language you feel comfortable with, but then you won't get much advice from me :( )
    * Mainly we'll be drawing fluctuation distribution functions and finding their properties: relative fluctuation level, skewness and kurtosis

#Resources

* D. A. D’Ippolito et al, Convective transport by intermittent blob-filaments: Comparison of theory and experiment, Physics of plasmas 18, 060501 (2011), particularly section IV (the entire thing is really long)
* [Rake probe wiki page](http://golem.fjfi.cvut.cz/wiki/Diagnostics/ParticleFlux/RakeProbe/index)
* [A YouTube introduction into moments of distribution functions](https://www.youtube.com/watch?v=BfeBhQemeUQ)