Three-dimensional magnetic reconnection through a moving magnetic null
Other literature type
Lukin, V. S.
Linton, M. G.
(issn: 1607-7946, eissn: 1607-7946)
arxiv: Physics::Plasma Physics | Physics::Space Physics | Astrophysics::Solar and Stellar Astrophysics
A computational study of three-dimensional magnetic reconnection
between two flux ropes through a moving reconnection site is
presented. The configuration is considered in the context of two
interacting spheromaks constrained by a perfectly conducting
cylindrical boundary and oriented to form a single magnetic field
null at its center. The initial magnetic field configuration is
embedded into a uniform thermal plasma and is unstable to tilting.
As the spheromaks tilt, their magnetic fields begin to reconnect at
the null, subsequently displacing both the null and the reconnection
site. The motion of the reconnection region and the magnetic null
are shown to be correlated, with stronger correlation and faster
reconnection observed in plasmas with lower thermal to magnetic
pressure ratio. It is also shown that ion inertial effects allow
for yet faster reconnection, but do not qualitatively change the
dynamics of the process. Implications of the coupling
between moving magnetic nulls and reconnection sites, as well as of
possible mechanisms for fast reconnection through a moving
reconnection region, are discussed. The simulations are conducted
using both single-fluid and Hall MHD plasma models within the HiFi
multi-fluid modeling framework.