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تسجيل مستخدم جديدConnecting the Sun and the Solar Wind: The Self-consistent Transition of Heating Mechanisms
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We have performed a 2.5 dimensional magnetohydrodynamic simulation that resolves the propagation and dissipation of Alfven waves in the solar atmosphere. Alfvenic fluctuations are introduced on the bottom boundary of the extremely large simulation box that ranges from the photosphere to far above the solar wind acceleration region. Our model is ab initio in the sense that no corona and no wind are assumed initially.The numerical experiment reveals the quasi-steady solution that has the transition from the cool to the hot atmosphere and the emergence of the high speed wind. The global structure of the resulting hot wind solution fairly well agree with the coronal and the solar wind structure inferred from observations. The purpose of this study is to complement the previous paper by Matsumoto & Suzuki (2012) and describe the more detailed results and the analysis method. These results include the dynamics of the transition region and the more precisely measured heating rate in the atmosphere. Particularly, the spatial distribution of the heating rate helps us to interpret the actual heating mechanisms in the numerical simulation.Our estimation method of heating rate turned out to be a good measure for dissipation of Alfven waves and low beta fast waves.
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The solar wind emanates from the hot and tenuous solar corona. Earlier studies using 1.5 dimensional simulations show that Alfv{e}n waves generated in the photosphere play an important role in coronal heating through the process of non-linear mode co
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The fourth orbit of Parker Solar Probe (PSP) reached heliocentric distances down to 27.9 Rs, allowing solar wind turbulence and acceleration mechanisms to be studied in situ closer to the Sun than previously possible. The turbulence properties were f
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We investigate how the proton distribution function evolves when the protons undergo stochastic heating by strong, low-frequency, Alfven-wave turbulence under the assumption that $beta$ is small. We apply our analysis to protons undergoing stochastic
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This paper reviews our growing understanding of the physics behind coronal heating (in open-field regions) and the acceleration of the solar wind. Many new insights have come from the last solar cycles worth of observations and theoretical work. Meas
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