Objective The possibility to improve the plasma confinement in stellarator type systems based on excluding locally trapped trajectories of charged particles by eliminating the local extreme of the magnetic field strength B on the magnetic surfaces will be investigated. Two different types of stellarator systems are supposed to be analysed. One is that with nonzero curvature and torsion of the magnetic axis thus with a poloidal inhomogeneity of the magnetic field strength, but with constant field strength along the magnetic axis. The second corresponds to stellarators with variation of the magnetic field strength along the magnetic axis. For the elimination of the locally trapped particles, both types of systems should have a topology of the lines B = constant identical to the analogous quasisymmetric systems (in the helical or in the poloidal direction) but should access a potentially much larger class of mod-B distributions with favourable neoclassical transport properties. In the second type of system, a particular case to be investigated is configurations with vanishing curvature of the magnetic axis in the regions of the extrema of B.The realization of the proposal and the search of systems optimised in such a way will be done analytically in the near-axis approximation as well as for the entire plasma volume using full-scale 3-D codes. This will allow to investigate not only the magnetic structure of the new optimised systems but also the equilibrium and stability beta limits as well as the most important transport processes. The participants expect to classify the 3-D magnetic system optimisation schemes based on the elimination of the local extrema of the magnetic field strength B on the magnetic surfaces. The search of such systems is expected to unveil stellarator configurations having moderate transport and a higher beta-limit than currently known. Programme(s) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Topic(s) 1B - Condensed Matter, Optics and Plasma Physics OPEN - OPEN Call Call for proposal Data not available Funding Scheme Data not available Coordinator Max-Planck-Gesellschaft EU contribution No data Address Wendelsteinstra?e 1 17491 Greifswald Germany See on map Total cost No data Participants (4) Sort alphabetically Sort by EU Contribution Expand all Collapse all Ecole Polytechnique Federale de Lausanne Switzerland EU contribution No data Address CRPP-PPB 1015 Lausanne See on map Total cost No data National Academy of Sciences of Ukraine Ukraine EU contribution No data Address Akademicheskaya str., 1 310108 Kharkov See on map Total cost No data Russian Academy of Sciences Russia EU contribution No data Address Miusskaya sq. 4 125047 Moscow See on map Total cost No data Russian Research Center "Kurchatov Institute" Russia EU contribution No data Address Kurchatov sq. 1 123182 Moscow See on map Total cost No data
