Mhd Simulations of Penumbra Fine Structure
نویسنده
چکیده
We present results of numerical 3D MHD simulations with radiative energy transfer of fine structure in a small sunspot of about 4 Mm width. The results show the development of filamentary structure with nearly field-free gaps, interlaced by concentrations of stronger magnetic field at the interface between the umbra and the outer field-free atmosphere. Calculated synthetic images show dark cores like those seen in the observations. They are the result of an elevated τ = 1 surface. The magnetic field in these cores is weaker and more horizontal than for adjacent brighter structures at the photosphere. Higher up in the atmosphere there are only small variations in field strength. Movies made show an inward migration of filamentary structures very similar to the patterns seen in observations of the inner penumbra. Although the filamentary structures in the simulations are too short compared to observations, most other aspects of the simulations appear consistent with observed penumbra filamentary structures. Subject headings: sunspots – magnetic field
منابع مشابه
Mhd Simulations of Penumbra Fine Structure
We present results of numerical 3D MHD simulations with radiative energy transfer of fine structure in a small sunspot of about 4 Mm width. The simulations show the development of filamentary structures and flow patterns that are, except for the lengths of the filaments, very similar to those observed. The filamentary structures consist of gaps with reduced field strength relative to their surr...
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تاریخ انتشار 2006