2020/06/30 by B. L. Alterman, Benjamin L. Alterman, Justin C. Kasper +2
Earth and Planetary Sciences · Physics and Astronomy · #Atmospheric Ozone and Climate #Flux (metallurgy) #Solar and Space Plasma Dynamics #Solar cycle #Solar cycle 22 #Solar cycle 23 #Solar maximum #Solar minimum #Solar wind #Stellar, planetary, and galactic studies #Sunspot #astro-ph.SR #physics.plasm-ph #physics.space-ph
paper · pdf · doi:10.1007/s11207-021-01801-9
Accepted in Solar Physics
openalex created_date 2020/11/09 · arxiv created 2021/03/25 · openalex publication_date 2021/04/01 · arxiv updated 2021/04/12 · openalex updated_date 2026/08/05
We study the solar wind helium-to-hydrogen abundance's (AHe) relationship to solar cycle onset. Using OMNI/Lo data, we show that AHe increases prior to sunspot number (SSN) minima. We also identify a rapid depletion and recovery in AHe that occurs directly prior to cycle onset. This AHe Shutoff happens at approximately the same time across solar wind speeds (vsw), implying that it is formed by a mechanism distinct from the one that drives AHe's solar cycle scale variation and vsw-dependent phase offset with respect to SSN. The time between successive AHe shutoffs is typically on the order of the corresponding solar cycle length. Using Brightpoint (BP) measurements to provide context, we infer that this shutoff is likely related to the overlap of adjacent solar cycles and the equatorial flux cancelation of the older, extended solar cycle during Solar Minima.