تقرير
Solar east-west flow correlations that persist for months at low latitudes are dominated by active region inflows
العنوان: | Solar east-west flow correlations that persist for months at low latitudes are dominated by active region inflows |
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المؤلفون: | Hanson, Chris S., Duvall Jr., Thomas L., Birch, Aaron C., Gizon, Laurent, Sreenivasan, Katepalli R. |
المصدر: | A&A 644, A103 (2020) |
سنة النشر: | 2020 |
المجموعة: | Astrophysics |
مصطلحات موضوعية: | Astrophysics - Solar and Stellar Astrophysics |
الوصف: | Context: Giant-cell convection is believed to be an important component of solar dynamics. For example, it is expected to play a crucial role in maintaining the Sun's differential rotation. Aims: We re-examine early reports of giant convective cells detected using correlation analysis of Dopplergrams. We extend this analysis using 19 years of space and ground-based observations of near-surface horizontal flows. Method: Flow maps are derived through local correlation tracking of granules and helioseismic ring-diagram analysis. We compute temporal auto-correlation functions of the east-west flows at fixed latitude. Results: Correlations in the east-west velocity can be clearly seen up to five rotation periods. The signal consists of features with longitudinal wavenumbers up to m=9 at low latitudes. Comparison with magnetic images indicates that these flow features are associated with magnetic activity. The signal is not seen above the noise level during solar minimum. Conclusions: Our results show that the long-term correlations in east-west flows at low latitudes are dominantly due to inflows into active regions and not to giant convective cells. Comment: 9 pages, 10 figures, accepted into A&A |
نوع الوثيقة: | Working Paper |
DOI: | 10.1051/0004-6361/202039108 |
URL الوصول: | http://arxiv.org/abs/2010.13052 |
رقم الأكسشن: | edsarx.2010.13052 |
قاعدة البيانات: | arXiv |
DOI: | 10.1051/0004-6361/202039108 |
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