Improved profile fitting and quantification of uncertainty in experimental measurements of impurity transport coefficients using Gaussian process regression

  title={Improved profile fitting and quantification of uncertainty in experimental measurements of impurity transport coefficients using Gaussian process regression},
  author={M. A. Chilenski and Martin Greenwald and Youssef M. Marzouk and N. T. Howard and Anne E. White and John E Rice and J. R. Walk},
  journal={Nuclear Fusion},
The need to fit smooth temperature and density profiles to discrete observations is ubiquitous in plasma physics, but the prevailing techniques for this have many shortcomings that cast doubt on the statistical validity of the results. This issue is amplified in the context of validation of gyrokinetic transport models (Holland et al 2009 Phys. Plasmas 16 052301), where the strong sensitivity of the code outputs to input gradients means that inadequacies in the profile fitting technique can… 

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