Friday, April 26, 2013

1304.6852 (N. C. Joshi et al.)

Study of Failed CME Core Associated with Asymmetric Filament Eruption    [PDF]

N. C. Joshi, A. K. Srivastava, B. Filippov, W. Uddin, P. Kayshap, R. Chandra
We present the multi-wavelength observations of asymmetric filament eruption, associated CME and coronal downflows on 2012 June 17-18 during 20:00-05:00 UT. We use SDO/AIA, STEREO-B/SECCHI observations to understand the filament eruption scenario and its kinematics. While LASCO C2 observations have been analyzed to study the kinematics of the CME and associated downflows. SDO/AIA limb observations show that the filament exhibits whipping like asymmetric eruption. STEREO/EUVI disk observations reveal a two ribbon flare underneath the south-eastern part of the filament that is most probably occurred due to reconnection process in the coronal magnetic field in the wake of the filament eruption. The whipping like filament eruption later gives a slow CME in which the leading edge and the core propagate respectively with the average speed of $\approx$ 540 km s$^{-1}$ and $\approx$ 126 km s$^{-1}$ as observed in the LASCO C2 coronagraph. The CME core formed by the eruptive flux-rope shows the outer coronal downflows with the average speed of $\approx$ 56 km s$^{-1}$ after reaching up to $\approx$4.33 $R_{\sun}$. Initially, the core decelerates with $\approx$ 48 m s$^{-2}$. The plasma first decelerates gradually up to the height of $\approx$4.33 $ R_{\sun}$ and then starts accelerating downward. We suggest a self-consistent model of a magnetic flux rope representing the magnetic structure of the CME core formed by eruptive filament that lost its previous stable equilibrium when reach at a critical height. With some reasonable parameters, and inherent physical conditions the model describes the non-radial ascending motion of the flux rope in the corona, its stopping at some height, and thereafter the downward motion, which are in good agreement with the observations.
View original: http://arxiv.org/abs/1304.6852

No comments:

Post a Comment