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arXiv · 0903.5041

Theory of incompressible MHD turbulence with scale-dependent alignment and cross-helicity

J. J. Podesta·A. Bhattacharjee
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Abstract

(Abridged) An anisotropic theory of MHD turbulence with nonvanishing cross-helicity is constructed based on Boldyrev's alignment hypothesis and probabilities p and q for fluctuations v and b to be positively or negatively aligned. Guided by observations suggesting that the normalized cross-helicity and the probability p are approximately constant in the inertial range, a generalization of Boldyrev's theory is derived that depends on the three ratios w+/w-, epsilon+/epsilon-, and p/q. The theory reduces to Boldyrev's original theory when w+ = w-, epsilon+ = epsilon-, and p = q.

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J. J. Podesta, A. Bhattacharjee. 2009-03-29. Theory of incompressible MHD turbulence with scale-dependent alignment and cross-helicity. https://doi.org/10.1088/0004-637x/718/2/1151

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