Kinetic Scale Spectral Features of Cross Helicity and Residual Energy in the Inner Heliosphere

Daniel Vech; Justin C. Kasper; Kristopher G. Klein; Jia Huang; Michael L. Stevens; Christopher H. K. Chen; Anthony W. Case; Kelly Korreck; Stuart D. Bale; Trevor A. Bowen; Phyllis L. Whittlesey; Roberto Livi; Davin E. Larson; David Malaspina; Marc Pulupa; John Bonnell; Peter Harvey; Keith Goetz; Thierry Dudok de Wit; Robert MacDowall

doi:10.3847/1538-4365/ab60a2

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arXiv · 1912.07719

Kinetic Scale Spectral Features of Cross Helicity and Residual Energy in the Inner Heliosphere

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Abstract

In this Paper, we present the first results from the Flux Angle operation mode of the Faraday Cup instrument onboard Parker Solar Probe. The Flux Angle mode allows rapid measurements of phase space density fluctuations close to the peak of the proton velocity distribution function with a cadence of 293 Hz. This approach provides an invaluable tool for understanding kinetic scale turbulence in the solar wind and solar corona. We describe a technique to convert the phase space density fluctuations into vector velocity components and compute several turbulence parameters such as spectral index, residual energy and cross helicity during two intervals the Flux Angle mode was used in Parker Solar Probe's first encounter at 0.174 AU distance from the Sun.

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Daniel Vech, Justin C. Kasper, Kristopher G. Klein, Jia Huang, Michael L. Stevens, Christopher H. K. Chen, Anthony W. Case, Kelly Korreck, Stuart D. Bale, Trevor A. Bowen, Phyllis L. Whittlesey, Roberto Livi, Davin E. Larson, David Malaspina, Marc Pulupa, John Bonnell, Peter Harvey, Keith Goetz, Thierry Dudok de Wit, Robert MacDowall. 2019-12-16. Kinetic Scale Spectral Features of Cross Helicity and Residual Energy in the Inner Heliosphere. https://doi.org/10.3847/1538-4365%2Fab60a2

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