Post on 20-Jan-2016
description
2007 PROM WORKSHOPSpace Sciences Lab / UC-Berkeley
Sheared-Field Prominences and the Eruptive Implications of Magnetic
Topology
B. J. Lynch, Y. Li, J. G. LuhmannS. K. Antiochos, C. R. DeVore
Two Basic CME Source Region Topologies
approximately
[Y. Li, 2006]
[Y. Li, 2006]
approximately
bipo
lar
mul
tipo
lar
Emo : “Maximally Open” ( 0% blue-red reconnection )
Emc : “Maximally Closed”( 100% blue-red reconnection )
Topology Determines Open State(s)bi
pola
rm
ulti
pola
r
only one Open State possibility
[DeVore et al., 2005]
B2
[DeVore et al., 2005]
[MacNeice et al., 2004]
(Br2+B
2)K.E.
0% rxn
100% rxn
Energy Evolution of MultipolarConfiguration in 2.5D
In MHD treatments of multipolar topologies, you can approach the no-reconnection limit before it “switches on”
Magnetic Neutral Lines
3D Null Point
Bipolar Multipolar
Magnetic Topologies in 3D
Magnetic Neutral Line
Bipolar Multipolar
Surface Field Evolution
Radial Velocity Evolution (=0)
Bipolar Multipolar
Magnetic Fieldline Evolution
Bipolar Multipolar
t = 15000 s
Flare reconnection starts
Magnetic + Kinetic Energy Evolution
Bipolar: EM(0) = 4.117e+31 ergsMultipolar: EM(0) = 2.566e+31 ergs
Initial (Potential) Magnetic Energies
EM=EM(t)-EM(0)
Notice the magnetic energy signature of the Br diffusion
EDIFF ~ 3.90e+31 ergs !!
Moderately fast breakout eruption (~500 km/s), but the rapid conversion from EM EK not super impressive
BUT, the Bipolar case doesn’t show any sign of eruption!
Summary & Current/Future Work
Bipolar Arcades Don’t Erupt Without Something Else Happening !!!
• Aly-Sturrock holds up in 3D!• Breakout works in 3D and probably for the reasons we think…• Theorists & modelers may still be relevant!
• Next simulation—• Get rid of that inner-boundary Br diffusion!• Slower driving, “cleaner” magnetic, kinetic energy profiles
(so far, so good… )
t = 5000 s t = 7500 s t = 10000 s
Sheared Field Prominence Structure
Three perspectives of the non-eruptive Bipolar fieldlines at t=15,000 seconds
Essentially the spherical version of sheared-arcade prominence model…[DeVore & Antiochos, 2000 and others]
3D Erupting Fieldlines3D Erupting Fieldlines
And because we can’t let the data folks have all the fun…