In this Letter we investigate the dependency with scale of the empirical probability distribution functions (PDF) of Elsasser increments using large sets of
This content will become publicly available on September 30, 2023
- Award ID(s):
- 2108834
- Publication Date:
- NSF-PAR ID:
- 10401570
- Journal Name:
- The Astrophysical Journal
- Volume:
- 937
- Issue:
- 2
- Page Range or eLocation-ID:
- 76
- ISSN:
- 0004-637X
- Sponsoring Org:
- National Science Foundation
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Abstract WIND data (collected between 1995 and 2017) near 1 au. The empirical PDF are compared to the ones obtained from high-resolution numerical simulations of steadily driven, homogeneous reduced MHD turbulence on a 20483rectangular mesh. A large statistical sample of Alfvénic increments is obtained by using conditional analysis based on the solar wind average properties. The PDF tails obtained from observations and numerical simulations are found to have exponential behavior in the inertial range, with an exponential decrement that satisfies power laws of the formα l ∝l −μ , wherel is the scale size, withμ between 0.17 and 0.25 for observations and 0.43 for simulations. PDF tails were extrapolated assuming their exponential behavior extends to arbitrarily large increments in order to determine structure function scaling laws at very high orders. Our results point to potentially universal scaling laws governing the PDF of Elsasser increments and to an alternative approach to investigate high-order statistics in solar wind observations. -
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