Parametric Transformation Analysis of Observed Coronal Magnetic Structures

by

G. Allen Gary
Solar Physics Team
NSSTC/Space Science Branch/XD12
NASA/Marshall Space Flight Center

Friday, 03 December 2004
Socialization : 2:15 p.m.
Presentation : 2:30 p.m.

Having the correct magnetic field would allow the determination of coronal magnetic free energy which drives solar eruptions, would allow the determination of which coronal mass ejection/eruptive flare model is correct, and would allow the determination of the pathway for the magnetic flux and charged energetic particles into the heliosphere. There is no existing magnetic field extrapolation method that can match field lines to the observed coronal loops structures seen in solar images. To address this deficiency, we are developing a method that quantitatively determines the dynamic topology, evolution and complexity of the opened and closed magnetic flux of the Sun from coronal imagery. The Parametric Transformation Analysis(PTA) uses a magnetic field transformation which parametrically transforms a field (and the associated field lines) to match the coronal features. The field lines are viewed as being embedded in a plastic medium. As the medium is deformed the field lines are carried along. This is similar to the frozen-in-field-line concept, but in the PTA the field line movement represents a transformation (or mapping) of one magnetic field solution into another magnetic field solution. This method allows the resulting magnetic field solution to match the magnetic field lines with EUV/SXR coronal loops by minimizing the differences in dispersion and direction of a collection of PTA-derived magnetic field lines and observed field lines (i.e., the centroids of the coronal loops). Our concept will be described in this seminar using spline theory.

BIOGRAPHICAL SKETCH:

G. Allen Gary is a member of the Space Science Department/MSFC at the National Space Science and Technology Center. He has been with NASA since 1969. He received his BS and MS from Ga. Tech, and his PhD degree in physics from the University of Georgia. For the last 20 years, he has been a member of the Solar Physics Team investigating the nature of coronal structures and solar magnetic fields. His research includes the general study of the magnetic field's configuration, evolution, and morphology together with estimation of the energy content of active regions. His theoretical work involves developing models of linear and nonlinear force-free magnetic fields and electric currents in the solar chromosphere-corona. He is participating in developing a space-based vector magnetograph which will be one of the core instruments for studying the processes that give rise to solar activity in the solar atmosphere. He is developing a triple etalon interferometer for the NSO/Advanced Technology Solar (4m) Telescope, confocal interferometers for imaging systems, and VUV interferometers for UV magnetographs.

Questions? - Email the author Allen.Gary@nasa.gov

Return To Colloquium Schedule