Small Magnetic Elements and Supergranulation

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Small Magnetic ElementsandSupergranulation

• Aaron Birch
• CORA Division, NWRA

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Status of Born Kernel Calculations
2d td 3d td hh rings dm
sound speed
flows
damping
source
B
Almost none of these include line of sight or
foreshortening
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Kernels

• Web interface to my 3D sound speed and flow
  kernel code will be available (helas).
• Other groups now working on Born approximation
  kernels !!
• Filling out the matrix is a major effort will
  require a number of FTE
• Currently unknown which kernels are needed only
  for small corrections and which are crucial.
  Simulations will help.

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Small Magnetic Elements

• With Duvall Gizon
• 2-point travel times from quiet Sun
• De-convolve magnetic field map from travel time
  map

Data
Model
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HMI will help with the noise
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Wave-like behavior
from Gizon et al.
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How Deep is Supergranulation ?
Braun et al. SOHO14 proceedings
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Supergranulation

• How deep is supergranulation ?
• Physics of wave-like behavior ?
• For that matter why is there a particular
  length scale for supergranulation ?