Electron Velocity Moments in the Solar Wind. I. Calibration of the Wind 3DP EESA Low Detector

Lynn B Wilson III; Stuart D Bale; Michael L Stevens; Bennett A Maruca; Kristopher G Klein; Mihailo M Martinovic; Jason M TenBarge

NASA NTRS · 20260003337

Electron Velocity Moments in the Solar Wind. I. Calibration of the Wind 3DP EESA Low Detector

Lynn B Wilson III·Stuart D Bale·Michael L Stevens·Bennett A Maruca·Kristopher G Klein·Mihailo M Martinovic·Jason M TenBarge

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Abstract

Calibrated measurements of electron velocity distribution functions (VDFs) are necessary to characterize fluid and kinetic processes in weakly collisional and nearly collisionless plasmas such as the solar wind. Therefore, we analyzed 3,996,051 electron VDFs observed by the Wind 3DP thermal electron detector near 1 astronomical unit (au) between January 1, 2005 and November 25, 2017. The data were calibrated for each electron VDF to produce accurate velocity moments in the solar wind. This is the first full solar cycle coverage electron velocity moment dataset in the near-Earth solar wind. Herein (Paper I) we discuss the calibration process/algorithms and the velocity moment constraints, uncertainties, and resulting public dataset. In the second paper (Paper II), we statistically analyze the electron velocity moment dataset.

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Lynn B Wilson III, Stuart D Bale, Michael L Stevens, Bennett A Maruca, Kristopher G Klein, Mihailo M Martinovic, Jason M TenBarge. 2026-04-29. Electron Velocity Moments in the Solar Wind. I. Calibration of the Wind 3DP EESA Low Detector. https://ntrs.nasa.gov/citations/20260003337

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