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EUV and radio spectrum of coronal holes

✍ Scribed by Franca Chiuderi Drago


Publisher
Springer
Year
1980
Tongue
English
Weight
677 KB
Volume
65
Category
Article
ISSN
0038-0938

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✦ Synopsis


From the intensity of 19 EUV lines whose formation temperature ~P ranges from 3 x I04 to 1.4 β€’ 106, two different models of the transition region and corona for the cell-centre and the network are derived. It is shown that both these models give radio brightness temperatures systematically higher than the observed ones. An agreement with radio data can be found only with lines formed at low temperature (~P< 8.5 β€’ 105) by decreasing the coronal temperature and the emission measure. The possibility of resolving the discrepancy by using different ion abundances has been also investigated with negative results.


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