2010/02/01 by Steven R. Cranmer, John L. Kohl, Cranmer, Steven R. +5
Physics and Astronomy · #FOS: Physical sciences #Solar and Space Plasma Dynamics #Solar and Stellar Astrophysics (astro-ph.SR)
paper · pdf · doi:10.48550/arxiv.1002.0297
openalex publication_date 2010/02/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
This paper reviews our growing understanding of the physics behind coronal\nheating (in open-field regions) and the acceleration of the solar wind. Many\nnew insights have come from the last solar cycle's worth of observations and\ntheoretical work. Measurements of the plasma properties in the extended corona,\nwhere the primary solar wind acceleration occurs, have been key to\ndiscriminating between competing theories. We describe how UVCS/SOHO\nmeasurements of coronal holes and streamers over the last 14 years have\nprovided clues about the detailed kinetic processes that energize both fast and\nslow wind regions. We also present a brief survey of current ideas involving\nthe coronal source regions of fast and slow wind streams, and how these change\nover the solar cycle. These source regions are discussed in the context of\nrecent theoretical models (based on Alfven waves and MHD turbulence) that have\nbegun to successfully predict both the heating and acceleration in fast and\nslow wind regions with essentially no free parameters. Some new results\nregarding these models - including a quantitative prediction of the lower\ndensity and temperature at 1 AU seen during the present solar minimum in\ncomparison to the prior minimum - are also shown.\n