Naslov
Role of electric fields in the MHD evolution of the kink instability

Autori
Lapenta, Giovanni ; Skender, Marina

Izvornik
New journal of physics (1367-2630) 19 (2017); 023034-1

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
MHD, magnetsko prespajanje, samoorganizacija, konopac toka
(MHD, kink instability, magnetic reconnection, self-organization, flux rope)

Sažetak
The discovery [Bonfiglio et al, Phys Rev Lett, 94, 145001, 2005] of electrostatic fields playing a crucial role in establishing plasma motion in the flux conversion and dynamo processes in reversed field pinches (RFP) is revisited. In order to further elucidate the role of the electrostatic fields, a flux rope configuration susceptible to the kink instability is numerically studied with an MHD code. Simulated non-linear evolution of the kink instability is found to confirm the crucial role of the electrostatic fields. A new insight is gained on the special function of the electrostatic fields: they lead the plasma towards the reconnection site at the mode resonant surface. Without this step the plasma column could not relax to its non-linear state, since no other agent is present to perform this role. While the inductive field generated directly by the kink instability is the dominant flow driver, the electrostatic field is found to allow the motion in the vicinity of the reconnection region.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA