HR: 1340h
AN: SH13A-0268 [Abstracts]
TI: Tracking Magnetic Footpoints with the Magnetic Induction Equation
AU: Schuck, P W
EM: schuck@ppdmail.nrl.navy.mil
AF: Naval Research Laboratory, 4555 Overlook Ave, SW, Washington, DC 20375
United States
AU: * Chen, J
EM: chen@ppd.nrl.navy.mil
AF: Naval Research Laboratory, 4555 Overlook Ave, SW, Washington, DC 20375
United States
AB:
The accurate estimation of magnetic footpoint velocities from a temporal
sequence of photospheric magnetograms is critical for estimating the magnetic
energy and helicity fluxes through the photosphere. A new technique for
determining the magnetic footpoint velocities from a sequence of magnetograms
is presented. This technique determines the optical flow for magnetic
footpoints by applying the magnetic induction equation and an affine velocity
profile to a windowed subregion of the magnetogram sequence producing an
overdetermined system that can be solved directly by standard least squares or
total least squares methods. The resulting optical flow field and associated
uncertainties are statistically consistent with the magnetic induction
equation and the affine velocity profile within this subregion. The general
technique has potential for application to other solar data sets where a
physical model for the underlying image dynamics can be applied.
DE: 7522 Helioseismology
DE: 7524 Magnetic fields
DE: 7529 Photosphere
DE: 7594 Instruments and techniques
SC: SPA-Solar and Heliospheric Physics [SH]
MN: Fall Meeting 2005