Flux Rope Acceleration and Enhanced Magnetic Reconnection Rate

Magnetic reconnection is explored on the Terrestrial Reconnection Experiment (TREX) for asymmetric inflow conditions and in a configuration where the absolute rate of reconnection is set by an external drive. Magnetic pileup enhances the upstream magnetic field of the high-density inflow, leading to an increased upstream Alfvén speed and helping to lower the normalized reconnection rate to values expected from theoretical consideration. In addition, a shock interface between the far upstream supersonic plasma inflow and the region of magnetic flux pileup is observed, important to the overall force balance of the system, thereby demonstrating the role of shock formation for configurations including a supersonically driven inflow. Despite the specialized geometry where a strong reconnection drive is applied from only one side of the reconnection layer, previous numerical and theoretical results remain robust and are shown to accurately predict the normalized rate of reconnection for the range of system sizes considered. This experimental rate of reconnection is dependent on system size, reaching values as high as 0.8 at the smallest normalized system size applied.

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The Effect of Thermal Pressure on Collisionless Magnetic Reconnection Rate

The Astrophysical Journal ◽

10.3847/1538-4357/abf48c ◽

2021 ◽

Vol 912 (2) ◽

pp. 152

Author(s):

Xiaocan Li ◽

Yi-Hsin Liu

Keyword(s):

Magnetic Reconnection ◽

Reconnection Rate ◽

Thermal Pressure

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Formation of coronal rain triggered by impulsive heating associated with magnetic reconnection

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936253 ◽

2019 ◽

Vol 630 ◽

pp. A123 ◽

Cited By ~ 5

Author(s):

P. Kohutova ◽

E. Verwichte ◽

C. Froment

Keyword(s):

Magnetic Reconnection ◽

Thermal Instability ◽

Flux Rope ◽

Coronal Loops ◽

Rain Event ◽

Subsequent Formation ◽

Standard Models ◽

Field Lines ◽

Impulsive Heating ◽

Coronal Rain

Context. Coronal rain consists of cool plasma condensations formed in coronal loops as a result of thermal instability. The standard models of coronal rain formation assume that the heating is quasi-steady and localised at the coronal loop footpoints. Aims. We present an observation of magnetic reconnection in the corona and the associated impulsive heating triggering formation of coronal rain condensations. Methods. We analyse combined SDO/AIA and IRIS observations of a coronal rain event following a reconnection between threads of a low-lying prominence flux rope and surrounding coronal field lines. Results. The reconnection of the twisted flux rope and open field lines leads to a release of magnetic twist. Evolution of the emission of one of the coronal loops involved in the reconnection process in different AIA bandpasses suggests that the loop becomes thermally unstable and is subject to the formation of coronal rain condensations following the reconnection and that the associated heating is localised in the upper part of the loop leg. Conclusions. In addition to the standard models of thermally unstable coronal loops with heating localised exclusively in the footpoints, thermal instability and subsequent formation of condensations can be triggered by the impulsive heating associated with magnetic reconnection occurring anywhere along a magnetic field line.

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MMS Observation of Secondary Magnetic Reconnection Beside Ion‐Scale Flux Rope at the Magnetopause

Geophysical Research Letters ◽

10.1029/2020gl089075 ◽

2020 ◽

Vol 47 (16) ◽

Author(s):

X.‐C. Dong ◽

M. W. Dunlop ◽

T.‐Y. Wang ◽

K. J. Trattner ◽

C. T. Russell ◽

...

Keyword(s):

Magnetic Reconnection ◽

Flux Rope

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Solar activities observed with the New Vacuum Solar Telescope

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316000235 ◽

2015 ◽

Vol 11 (S320) ◽

pp. 315-320

Author(s):

Shuhong Yang ◽

Jun Zhang

Keyword(s):

Magnetic Reconnection ◽

Flux Rope ◽

Observational Evidence ◽

Small Scale ◽

Solar Telescope ◽

New Name ◽

Direct Observations ◽

Filament Activation ◽

First Time

AbstractBased on the New Vacuum Solar Telescope observations, some new results about the solar activities are obtained. (1) In the Hα line, a flux rope tracked by filament activation is detected for the first time. There may exist some mild heating during the filament activation. (2) The direct observations illustrate the mechanism of confined flares, i.e., the flares are triggered by magnetic reconnection between the emerging loops and the pre-existing loops and prevented from being eruptive by the overlying loops. (3) The solid observational evidence of magnetic reconnection between two sets of small-scale loops is reported. The successive slow reconnection changes the conditions around the reconnection area and leads to the rapid reconnection. (4) An ensemble of oscillating bright features rooted in a light bridge is observed and given a new name, light wall. The light wall oscillations may be due to the leakage of p-modes from below the photosphere.

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