Abstract:
We study the triggering mechanism of a limb-prominence eruption and the associated coronal mass ejection
(
CME
)
near AR 12342 using
Solar Dynamics Observatory
and Large Angle and Spectrometric Coronagraph
/
Solar Heliospheric Observatory
observations. The prominence is seen with an embedded
fl
ux thread
(
FT
)
at one
end and bifurcates from the middle to a different footpoint location. The morphological evolution of the FT is
similar to that of an unstable
fl
ux rope
(
FR
)
, which we regard as a prominence-embedded FR. The FR twist
exceeds the critical value. In addition, the morphology of the prominence plasma in 304
Å
images marks the
helical nature of the magnetic skeleton, with a total of 2.96 turns along arc length. The potential
fi
eld extrapolation
model indicates that the critical height of the background magnetic
fi
eld gradient falls within the inner corona
(
105 Mm
)
, which is consistent with the extent of coronal plasma loops. These results suggest that the helical kink
instability in the embedded FR caused the slow rise of the prominence to the height of the torus instability domain.
Moreover, the differential emission measure analysis unveils heating of the prominence plasma to coronal
temperatures during an eruption, suggesting reconnection-related heating underneath the upward rising embedded
FR. The prominence starts with a slow rise motion of 10 km s
−
1
, which is followed by fast and slow acceleration
phases that have an average acceleration of 28.9 m s
−
2
and 2.4 m s
−
2
in C2 and C3
fi
eld of view, respectively. As
predicted by previous numerical simulations, the observed synchronous kinematic pro
fi
les of the CME leading
edge and the core support the involved FR instability in the prominence initiation.
