Electron density and temperature structure of two limb active regions observed by SOHO-CDS

被引:30
作者
Mason, HE
Landi, E
Pike, CD
Young, PR
机构
[1] Univ Cambridge, Dept Appl Math & Theoret Phys, Cambridge CB3 9EW, England
[2] Univ Florence, Dipartimento Astron & Sci Spazio, I-50125 Florence, Italy
[3] Rutherford Appleton Lab, Dept Space Sci, Didcot OX11 0QX, Oxon, England
关键词
D O I
10.1023/A:1005246220208
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The analysis of two active regions on the limb using observations from SOHO-CDS allows us to determine the electron density and temperature distribution of the coronal emission. We find that the active regions have hot cores (3 x 10(6) K) with larger cooler (10(6) K) loop structures extending above the limb. The electron number density, determined using the Si X diagnostic line ratio, is found to be highest in the active region core (greater than 2.3 x 10(9) cm(-3)). Electron number density values are determined for a range of spectral lines from different ions and are found to increase with temperature between 0.8 and 2.5 x 10(6) K. These results are consistent with recent models of enhanced heating along the compact core of active regions, where the magnetic field shear is strongest.
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页码:129 / 146
页数:18
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