Gradual pre-eruptive phase of solar coronal eruptions
Vršnak, Bojan, Gradual pre-eruptive phase of solar coronal eruptions, Frontiers in Astronomy and Space Sciences, 6, 28 (2019) (ADS)
(click on the image for a larger version)
A nicely drawn cartoon illustrating an MHD theorist's view of two apparently
alternative views of how poloidal flux may be injected into a coronal magnetic
flux tube: either by bodily twisting one end of the tube, or by pushing against
it with an obliquely oriented field.
These themes occur repeatedly in the Archive, of course, notably in the
context of the "hoop force" described in the classic
Chen-Krall cartoon.
Most of these works swerve away from actually explaining how a flux tube may
exist in the first place, since in this kind of cartoon representation (and
in the modeling) the tube has a defining flux surface that of course must
lose its identity at its base where it disappears into a
Piddington-style magnetic mess.
See the Ionson cartoon for the alternative
more electrodynamical point of view.
A nicely drawn cartoon illustrating an MHD theorist's view of two apparently alternative views of how poloidal flux may be injected into a coronal magnetic flux tube: either by bodily twisting one end of the tube, or by pushing against it with an obliquely oriented field. These themes occur repeatedly in the Archive, of course, notably in the context of the "hoop force" described in the classic Chen-Krall cartoon. Most of these works swerve away from actually explaining how a flux tube may exist in the first place, since in this kind of cartoon representation (and in the modeling) the tube has a defining flux surface that of course must lose its identity at its base where it disappears into a Piddington-style magnetic mess. See the Ionson cartoon for the alternative more electrodynamical point of view.