Experimental evidence for the drift wave nature of the weakly coherent mode in ASDEX Upgrade I-mode plasmas
06/13/2024
Manuel Herschel investigated the dispersion behavior of the weak coherent mode (WCM) in I-modes in ASDEX Upgrade. The WCM propagating in the electron-diamagnetic direction is in agreement with the dispersion relation of drift waves if temperature fluctuations can be neglected. This confirms important assumptions in our theory. The paper was recently published in Nuclear Fusion.
Tobias Tork defended his Master's thesis
06/10/2024
Today Tobias Tork defended his master thesis with the topic 'Estimation of turbulent transport coefficients from single point density fluctuations'. In his master thesis Tobias Tork has developed a method that allows to determine transport coefficients of particles and heat transport in fusion plasmas only from measurements of density or temperature fluctuations via conditioning. The method was validated by means of gyrofluid simulations and experiments in ASDEX Upgrade and Wendelstein 7-X. The method allows simple and quite precise estimation of the transport coefficients with existing diagnostics. We believe that this may represent a methodological breakthrough. Special thanks at this point also to Nicolas Bian for the great idea, Felix Reimold for the great support at IPP Greifswald, Carsten Killer and Gustavo Grenfell for the measurement data from W7-X and AUG and Dirk Reiser for numerical support.
Guests from IPP Garching
On April 3rd we had Dr. Stegmeir and on May 10th Dr. Grover from IPP Garching as guests in our working group. We would like to thank them for their interest and hope for a good future cooperation.
SepOS has been extended to experiments with the unfavorable grad-B drift
04/05/2024
The SepOS model has been extended to experiments with the unfavorable grad-B drift. The combination with the theory of the magnetic-shear-induced Reynolds stress offers a possibility to quantitatively explain the phenomena. The work was recently published in Nuclear Fusion.
Nils Müller in Physics of Plasmas Early Career Collection 2023
03/20/2024
Physics of Plasmas recently launched the 2023 Early Career Collection, a collection of outstanding papers from the next generation of plasma physicists. To be eligible, the defense of the doctoral degree must have taken place less than five years ago at the time of submission of the manuscript. Nils Müller's work is based on his bachelor thesis and is listed in the collection. We are therefore particularly proud of his achievement and join in the congratulations.
Home match
From February 26th to February 29th, 2024, the DPG Spring Conference 2024 took place on the campus of the University of Greifswald. Stefan and Tiano presented our experiments. As co-hosts of the conference, we hope everyone had a great experience in our small, beautiful city. We loved it and would like to have conferences in smaller cities more often. It was nice to see old friends and meet new people.
visit by Dr. Flock
On February 15th, Dr. Mario Flock, group leader at the Max Planck Institute for Astronomy, visited us. We had great conversations and good ideas.
International guests visit the group
02/02/2024
On Thursday Dr. Ümmügül Erözbek Güngör from the Middle East Technical University (Ankara, Turkey) and today on Friday Prof. Dr. Takashi Nishizawa from Kyushu University (Fukuoka, Japan) visited us to have a look at our laboratories for future cooperation. We hope they found the experiments interesting and that we can welcome them to Greifswald more often or that we can be guests in Turkey or Japan.