Experimental verification of the role of electron pressure in
fast magnetic reconnection with a guide field
Authors: W. Fox, J. Jara-Almonte, J. Yoo, H. Ji, and M.
Yamada
Abstract: We report detailed laboratory observations of the
structure of a reconnection current sheet in a two-fluid plasma
regime with a guide magnetic field. We make the first detailed
laboratory measurements and quantitative analysis of the quadrupolar
electron pressure variation in the ion- di ffusion region, as
originally predicted by extended MHD simulations. The projection of
the electron pressure gradient parallel to the magnetic field
contributes signifi cantly to balancing the parallel electric
fi eld, and the resulting cross-field electron jets in the
reconnection layer are diamagnetic in origin. These results
demonstrate how parallel and perpendicular force balance are coupled
in guide field reconnection and con rm basic theoretical models of
the importance of electron pressure gradients in establishing a
current sheet geometry favorable for fast magnetic reconnection.