Fermi Acceleration in Plasmoids Interacting with Fast Shocks of Reconnection via Fractal Reconnection

Nishizuka, N. and K. Shibata, Fermi Acceleration in Plasmoids Interacting with Fast Shocks of Reconnection via Fractal Reconnection, Physical Review Letters, 110, 051101 (2013) (ADS)

The cartoon

(click on the image for a larger version)

The CSHKP model, well-illustrated in a major fraction of all the cartoons in this Archive, can possibly create a fast-mode termination shock in an ideal case, although the most direct observations of a reconnection outflow that could do this don't seem to show super-Alfv{\' e}nic speeds. But on microscales, who knows, and this process associated with a "collapsing trap" might proceed. This cartoon envisions a plasmoid (really 3D in nature) being driven by the flow through its shock (the horizontal line), possibly doing first-order Fermi acceleration augmented by the betatron effect. As implausible and unobservable as this intricate mechanism may seem, it is a leading candidate for impulsive-phase electron acceleration, it seems.

Date: 2020 August 19