اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدDevelopment and Parameters of a Non-Self-Similar CME Caused by Eruption of a Quiescent Prominence
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The eruption of a large quiescent prominence on 17 August 2013 and associated coronal mass ejection (CME) were observed from different vantage points by Solar Dynamics Observatory (SDO), Solar-Terrestrial Relations Observatory (STEREO), and Solar and Heliospheric Observatory (SOHO). Screening of the quiet Sun by the prominence produced an isolated negative microwave burst. We estimated parameters of the erupting prominence from a model of radio absorption and measured from 304 AA images. Their variations obtained by both methods are similar and agree within a factor of two. The CME development was studied from the kinematics of the front and different components of the core and their structural changes. The results are verified using movies in which the CME expansion was compensated according to the measured kinematics. We found that the CME mass ($3.6 times 10^{15}$ g) was mainly supplied by the prominence ($approx 6 times 10^{15}$ g), while a considerable part drained back. The mass of the coronal-temperature component did not exceed $10^{15}$ g. The CME was initiated by the erupting prominence, which constituted its core and remained active. The structural and kinematical changes started in the core and propagated outward. The CME structures continued to form during expansion, which did not become self-similar up to $25 R_odot$. The aerodynamic drag was insignificant. The core formed until $4 R_odot$. Some of its components were observed to straighten and stretch forward, indicating the transformation of tangled structures of the core into a simpler flux rope, which grew and filled the cavity as the CME expanded.
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