Identifying Coronal Holes in Solar Disk Images (and how to compare to models)
Correlation Length of Energy at the Base of Coronal Holes
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Transcript of Correlation Length of Energy at the Base of Coronal Holes
Correlation Length of Energy at the Base of Coronal Holes
Valentina Abramenko 1
Gary Zank 2
Alexander Dosch 2
Vasyl Yurchyshyn 1
1 - Big Bear solar Observatory of NJIT, CA
2 – CSPAR, Univ. of Alabama in Nuntsville, AL
Photospheric motions are immediately transferred into the chromosphere and corona
Magnetic and velocity fluctuations were analyzed in the photosphere inside two coronal holes
u2
ux , uy
Correlation Function of u2 :
Correlation function allows to estimate a characteristic length λof energy containing structures, which defines directly the heating rate:
Matthaeus et al. 1999:
Zank et al. 2012:
Correlation Function:
Correlation function allows to estimate a characteristic length by different ways:
1.To determine the Batchelor integral scale:
2. From an exponential fit to calculate the correlation length ζ
3. To calculate the e-folding scale L of the correlation function.
Calculated Correlation Functions of u2 structures
Parallel and Normal Correlation Functions of ux and uy velocity components
16 Mm
HMI (0.5”) 2011/08/12
SOT/SP (0.16”) 2007/03/10NST (0.098”) 2012/06/02
36 Mm120 Mm
Magnetic Field in Coronal Holes
Correlation Functions from magnetic field fluctuations
Magnetic and Kinetic Power Specra
at the Base of Coronal HolesValentina Abramenko
Big Bear solar Observatory of NJIT, CA
Kinetic and Magnetic Energy SpectraObserved Velocity Spectra
Kinetic and Magnetic Energy SpectraObserved Magnetic Spectra
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XXV IUGG/IAGA, Melbourne, Australia
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