Egor Illarionov, Andrey Tlatov, Ivan Berezin, Nadezhda Skorbezh
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引用次数: 0
Abstract
Coronal holes (CHs) are widely considered as the main sources of high-speed solar wind streams. We validate this thesis comparing the smoothed time series of solar wind speed measured by the Advanced Composition Explorer (ACE) and various indices of CH areas constructed from the CH catalog compiled at the Kislovodsk Mountain Astronomical Station for the period 2010 – 2025. The main result is that we find specific indices of CH areas that give a strong correlation with smoothed solar wind speed variations. As an example, 1-year averaged areas of CHs located within 30 degrees of the solar equator yield a correlation of 0.9 with 1-year averaged solar wind speed. This strong correlation is a feature of the particular CH catalog, and considering an alternative CH catalog obtained using the Spatial Possibilistic Clustering Algorithm (SPoCA) from the Heliophysics Event Knowledgebase (HEK), the same index provides a correlation of only 0.3. Although the fact that the correlation significantly depends on the catalog requires a separate discussion, we conclude that if some of the catalogs can be used to construct a reliable indicator of solar wind speed variations, then this methodology should be maintained further. Additionally, we present time-latitude diagrams of rolling correlation between CH areas and solar wind speed, which, in our opinion, can be used to reveal source CHs for high-speed solar wind streams.
期刊介绍:
Solar Physics was founded in 1967 and is the principal journal for the publication of the results of fundamental research on the Sun. The journal treats all aspects of solar physics, ranging from the internal structure of the Sun and its evolution to the outer corona and solar wind in interplanetary space. Papers on solar-terrestrial physics and on stellar research are also published when their results have a direct bearing on our understanding of the Sun.