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Figure 4 | Earth, Planets and Space

Figure 4

From: Coronal magnetic field and the plasma beta determined from radio and multiple satellite observations

Figure 4

Results of the radio and EUV observations of the active region. (a) EUV image at 304 Å observed with AIA. (b) EUV image at 171 Å observed with AIA. (c) Peak emission measure derived from AIA observations. (d) Peak temperature derived from AIA observations. (e) Emission measure derived from the brightness temperature at 17 GHz and the temperature from AIA using the optically thin assumption. Note that optically thick emission, corresponding to the brightness temperature of the τ =1 layer, was observed in the on-disc region. Hence, the emission measure for the region inside the solar disc is incorrect. (f) Total deferential emission measure (DEM) in the region enclosed by the dashed white rectangle in (a). White contours in (a) to (e) show the radio intensity at 17 GHz (levels =10,000, 20,000, 30,000 K). Red contours in (a) to (e) show the degree of circular polarization (levels =1.0%, 2.0%, 3.0%) at 17 GHz.

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