X-ray and ultraviolet emission and the physics of solar flares
Pikelner, S. B. and M. A. Livshits, X-ray and ultraviolet emission and the physics of solar flares, Soviet Ast., 21, 601-611 (1977) (ADS)
(click on the image for a larger version)
The rather detailed cartoon appeared in 1977 in the often brilliant
Soviet-era literature.
The eminent research workers included not just Pikel'ner himself, but
other legendary figures such as Ginzburg, Gordon, Kaplan, Korchak,
Syrovatskii, Shklovsky,
Tsytovich, and many others, all of whom were
involved in theoretical problems of solar activity at some point
early in the history of plasma astrophysics.
This paper reviews a lot of their work, plus observations from both
within the USSR and from the world beyond.
It touches on all aspects of the theory of flares, ranging
from hydrodynamics and radiative transfer through particle acceleration.
The cartoon embodies most of the features that we talk about today
in flare theory a la CSHKP, and avoids the open-field
geometry that our modern
overemphasis on CME physics (too much "space weather"?) has induced.
Here we meet concentric but oppositely-directed closed fields,
resulting from flux emerging in a
quadrupolarconfiguration, and
therefore with a basically horizontal current sheet separating them.
Note that the authors intriguingly draw the current sheet ("layer")
as having a cylindrical cross-section.
The authors regarded the nonthermal electrons as a sideshow, and had
them emitting hard X-rays in footpoints way up at 10,000 km,
but the data in the 1970's was not as good as what we have today.
Now we'd put the hard X-ray source right down at the upper photosphere.
The rather detailed cartoon appeared in 1977 in the often brilliant Soviet-era literature. The eminent research workers included not just Pikel'ner himself, but other legendary figures such as Ginzburg, Gordon, Kaplan, Korchak, Syrovatskii, Shklovsky, Tsytovich, and many others, all of whom were involved in theoretical problems of solar activity at some point early in the history of plasma astrophysics. This paper reviews a lot of their work, plus observations from both within the USSR and from the world beyond. It touches on all aspects of the theory of flares, ranging from hydrodynamics and radiative transfer through particle acceleration.
The cartoon embodies most of the features that we talk about today in flare theory a la CSHKP, and avoids the open-field geometry that our modern overemphasis on CME physics (too much "space weather"?) has induced. Here we meet concentric but oppositely-directed closed fields, resulting from flux emerging in a quadrupolar configuration, and therefore with a basically horizontal current sheet separating them. Note that the authors intriguingly draw the current sheet ("layer") as having a cylindrical cross-section. The authors regarded the nonthermal electrons as a sideshow, and had them emitting hard X-rays in footpoints way up at 10,000 km, but the data in the 1970's was not as good as what we have today. Now we'd put the hard X-ray source right down at the upper photosphere.