Residual strahls in solar wind electron dropouts: Signatures of magnetic connection to the Sun, disconnection, or interchange reconnection?

Crooker, N. U. and C. Pagel, Residual strahls in solar wind electron dropouts: Signatures of magnetic connection to the Sun, disconnection, or interchange reconnection?, J. Geophys. Res., 113, 2106-+ (2008) (ADS)

The cartoon

(click on the image for a larger version)

A "strahl" here refers to an antisunward beam, or pitch-angle anisotropy. Such wonderful lessons for solar physicists! Pitch-angle distributions are really not very accessible by remote-sensing (astronomical) techniques, so we should pore over the cartoons describing observations of them wherever they can be measured, such as here in the solar wind. Besides, it is in color! Note the other jargon "halo" - this refers to the isotropic non-thermal tail of the particle distribution function in the solar wind.

      The original cartoon describing "interchange reconnection" is also here Crooker in this Archive, of course. That may or may not make it any easier to describe how to view these processes in 3D, where all solar field actually must be considered "closed" until evidence is found for truly torus-like flux tubes, bounded by actual flux surfaces, drifting outwards in the solar wind like lost jellyfish (or doughnuts) on the tide. Nobody has captured such a weird field geometry in any of our cartoons here yet...

Date: 2010 April 21

Update: 2019 February 12