Interchange Slip-Running Reconnection and Sweeping SEP Beams
Masson, S., G. Aulanier, E. Pariat, and K. L. Klein, Interchange Slip-Running Reconnection and Sweeping SEP Beams, Sol. Phys., 276, 199-217 (2012) (ADS)
(click on the image for a larger version)
This cartoon bravely attacks one of the outstanding problems of
heliospheric physics, namely how the solar energetic particles
spread out into a large solid angle within the solar wind.
By a remarkable alphabetical coincidence, this is the same problem
tackled in the adjacent
Martinell cartoon
but with greater artistic panache.
This "escape" problem for SEPs has always seemed especially intractable
for the type-III-burst electrons, at least as conventional wisdom
understands them physically.
These are identifiable with highly collimated soft X-ray jets, and
one also can infer a tight beam structure directly and indirectly
from the radio data.
So, how does a point in space and time map onto a volume
(or at least, onto an area)?
The authors have "rounded up the usual suspect," to paraphrase
Claude Rains: in
this case, magnetic reconnection.
This old and ill-understood concept is dressed up here with two adjectives:
"slip-running" and "interchange", but it seems to be the same
unknown microphysics as before.
The problem has always been that a current sheet is basically a sheet,
i.e. a a 2D manifold, whereas the solar wind is 3D.
The authors discuss this in terms of the "spine" field line, which is 1D.
So the Archivist is perplexed geometrically, seeking a space-filling
(3D) population of SEPs and finding the wrong dimensionality in the
proposed source.
This cartoon bravely attacks one of the outstanding problems of heliospheric physics, namely how the solar energetic particles spread out into a large solid angle within the solar wind. By a remarkable alphabetical coincidence, this is the same problem tackled in the adjacent Martinell cartoon but with greater artistic panache. This "escape" problem for SEPs has always seemed especially intractable for the type-III-burst electrons, at least as conventional wisdom understands them physically. These are identifiable with highly collimated soft X-ray jets, and one also can infer a tight beam structure directly and indirectly from the radio data. So, how does a point in space and time map onto a volume (or at least, onto an area)?
The authors have "rounded up the usual suspect," to paraphrase Claude Rains: in this case, magnetic reconnection. This old and ill-understood concept is dressed up here with two adjectives: "slip-running" and "interchange", but it seems to be the same unknown microphysics as before. The problem has always been that a current sheet is basically a sheet, i.e. a a 2D manifold, whereas the solar wind is 3D. The authors discuss this in terms of the "spine" field line, which is 1D. So the Archivist is perplexed geometrically, seeking a space-filling (3D) population of SEPs and finding the wrong dimensionality in the proposed source.