1. Department of Physics, University of Milan-Bicocca 1 , Milan, Italy
2. Institute for Plasma Science and Technology, CNR 2 , Milan, Italy
3. Diagnostic Program, ITER Organization 3 , Saint Paul-lez-Durance, France
4. Independent researcher 4 , St. Petersburg, Russian Federation
5. Department of Physics, University of Milan 5 , Milan, Italy
6. UKRI-STFC, Rutherford Appleton Laboratory 6 , Didcot, United Kingdom