Chaotic escape of impurities and sticky orbits in toroidal plasmas

Autor(es)

Souza, L. C. ; Sales, M. R. ; Mugnaine, M. ; Szezech, J. D. ; Caldas, I. L. ; Viana, R. L.

• Tipo de documento: Artigo Científico
• Fonte: PHYSICAL REVIEW E; v. 109, n. 1, p. 10-pg., 2024-01-05.

Resumo

We investigate chaotic impurity transport in toroidal fusion plasmas (tokamaks) from the point of view of passive advection of charged particles due to E x B drift motion. We use realistic tokamak profiles for electric and magnetic fields as well as toroidal rotation effects, and consider also the effects of electrostatic fluctuations due to drift instabilities on particle motion. A time-dependent one degree-of-freedom Hamiltonian system is obtained and numerically investigated through a symplectic map in a Poincare surface of section. We show that the chaotic transport in the outer plasma region is influenced by fractal structures that are described in topological and metric point of views. Moreover, the existence of a hierarchical structure of islands-around-islands, where the particles experience the stickiness effect, is demonstrated using a recurrence-based approach. (AU)

• Processo FAPESP: 22/04251-7 - Estruturas Fractais em Física de Plasmas
• Beneficiário: Iberê Luiz Caldas
• Modalidade de apoio: Auxílio à Pesquisa - Pesquisador Visitante - Brasil
• Processo FAPESP: 18/03211-6 - Dinâmica não linear
• Beneficiário: Iberê Luiz Caldas
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 22/12736-0 - Oscilações em plasmas confinados magnéticamente
• Beneficiário: Michele Mugnaine
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado