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Jerry
2010-Jul-04, 03:19 AM
http://arxiv.org/ftp/arxiv/papers/1006/1006.5815.pdf

Deflection of coronal rays by remote CMEs: shock wave or magnetic pressure?


We conclude that all studied events do not correspond to the expected pattern of shock wave propagation in the corona. Coronal ray deflection can be interpreted as the influence of the magnetic field of a moving flux rope related to a CME.

So...why are there magnetic ropes skipping out from the sun?

astromark
2010-Jul-04, 05:38 AM
' Jerry.,' We are talking of this in the questions and answers... as this is very close to your inquiring... question

Ropes of magnetic flux... Think of how lightning travels and you are getting some place closer...

When the sun unleashes a eruptive flare event. Magnetic fluxes are just part of the energies released.

Fortunately at 93 million miles we have dodged the harmful effects thus far.... Its normal.

tusenfem
2010-Jul-04, 11:07 AM
http://arxiv.org/ftp/arxiv/papers/1006/1006.5815.pdf

Deflection of coronal rays by remote CMEs: shock wave or magnetic pressure?

So...why are there magnetic ropes skipping out from the sun?

I am at a loss about your title, because the paper is apparently about as you write in your post "Deflection of coronal rays by remote CMEs: shock wave or magnetic pressure?" and not whether CMEs are magnetically or shock driven. The next sentence after the one that you quoted says:



Coronal ray deflection can be interpreted as the influence of the magnetic field of a moving flux rope related to a CME. The motion of a large-scale flux rope away from the Sun creates changes in the structure of surrounding field lines, which are similar to the kink propagation along coronal rays.


We know there are shock waves related to CMEs and we know that CMEs are magnetic structures.

ETA: skipping to the conclusion



We have analyzed five events of prominent coronal ray deflections by the CMEs. We have
measured the speed of the kink disturbance propagation along the rays in two spatial intervals
and compared it with the speed of the frontal structure and the core of CMEs. Streamer
deflections were observed for cases with both fast and slow CMEs. We did not find strong
evidence of shock wave propagation in the corona. The observed coronal ray deflections can be
interpreted as the influence of the magnetic field of a moving flux rope related to a CME. A
simple model of radial coronal magnetic field was considered. The motion of a large-scale flux
rope away from the Sun creates changes in the structure of surrounding field lines, which are
similar to the kink propagation along coronal rays. The retardation of the potential is taken into
account since the flux rope moves at high speed comparable with the Alfvén speed. It is expected
that fast CMEs drive shocks in the corona. Distant streamer deflections are often assumed to be
indirect evidence of shocks. However, there are other reasons for the streamer deflections, and at
least many of them are not deflected by the shocks. Careful analysis of these events could give
us valuable information about coronal plasma, for example, an estimation of Alfvén speed.


So, apparently it was expected that all cororal ray deflections would be indirect evidence for shock waves.
Now they have found that other processes can also deflect coronal rays.

Jerry
2010-Jul-07, 05:18 AM
http://arxiv.org/abs/1007.0954

Self Consistent Models of the Solar Wind



This paper summarizes some of the essential ingredients of realistic and self-consistent models of solar wind acceleration. It also outlines the major issues in the recent debate over what physical processes dominate the mass, momentum, and energy balance in the accelerating wind. A key obstacle in the way of producing realistic simulations of the Sun-heliosphere system is the lack of a physically motivated way of specifying the coronal heating rate...

Only a small fraction of the mechanical energy in the Sun’s sub-photospheric convection zone needs to be converted to heat in order to power the corona. However, it has proved exceedingly difficult to distinguish between competing theoretical models using existing observations..

tusenfem
2010-Jul-07, 06:58 AM
And what, prithee, has this to do with CMEs?