THEORY OF INCOMPRESSIBLE MAGNETOHYDRODYNAMIC TURBULENCE WITH SCALE-DEPENDENT ALIGNMENT AND CROSS-HELICITY
- Center for Integrated Computation and Analysis of Reconnection and Turbulence, University of New Hampshire, Durham, New Hampshire 03824 (United States)
A phenomenological anisotropic theory of MHD turbulence with nonvanishing cross-helicity is constructed based on Boldyrev's phenomenology and probabilities p and q for fluctuations {delta}v{sub perpendicular} and {delta}b{sub perpendicular} to be positively or negatively aligned. The positively aligned fluctuations occupy a fractional volume p and the negatively aligned fluctuations occupy a fractional volume q. Guided by observations suggesting that the normalized cross-helicity {sigma}{sub c} and the probabilities p and q are approximately scale invariant in the inertial range, a generalization of Boldyrev's theory is derived that depends on the three ratios w {sup +}/w {sup -}, {epsilon}{sup +}/{epsilon}{sup -}, and p/q. It is assumed that the cascade processes for positively and negatively aligned fluctuations are both in a state of critical balance and that the eddy geometries are scale invariant. The theory reduces to Boldyrev's original theory when {sigma} {sub c} = 0, {epsilon}{sup +} = {epsilon}{sup -}, and p = q and extends the theory of Perez and Boldyrev when {sigma}{sub c} {ne} 0. The theory is also an anisotropic generalization of the theory of Dobrowolny, Mangeney, and Veltri.
- OSTI ID:
- 21455070
- Journal Information:
- Astrophysical Journal, Vol. 718, Issue 2; Other Information: DOI: 10.1088/0004-637X/718/2/1151; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
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