We plan to hold two special interdisciplinary plenary contributed sessions. The topics of these sessions are:
P1) Why does the plasma rotate without external torque ?
Since the discovery of non-diffusive momentum transport in 1995, the plasma rotation without external torque has been a long term problem and topic of interest, for which the mechanism has not been clarified. Recently, theoretical models have been proposed to explain the rotation due to the intrinsic torque. In this session, experimental observations and theoretical models and simulations will be discussed to obtain a deeper understanding of the physics mechanism of intrinsic torque and rotation.
P2) Why is the transport of plasmas NOT determined by a local quantity ?
The non-local phenomena, where the core temperature increases associated with the drop of temperature at the edge, was found in 1995. After that, numerous experimental evidence for the coupling of core and edge transport in the plasma emerged. However, the physics mechanism to connect the transport at different plasma locations has been open to question. The observation of long-range turbulence and mesoscale structures suggests that the coupling between large scale or mesoscale and short-range turbulence would be a candidate to explain the mechanism. In this session, non-local phenomena for transport and mesoscale structures and possible models will be discussed.
The purpose of these sessions is to discuss problems that have not been clarified yet. Loosely following the style of the EU-US TTF meetings, the plenary sessions will consist of brief introductory overviews, several contributed oral papers, and group discussion, with a discussion leader. APTWG meeting participants are encouraged to submit contributed papers to these two special sessions. The scope of the topics is intentionally broad, so as to accommodate a diversity of approaches.