Physics – Plasma Physics
Scientific paper
Dec 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010agufmsm51c1837d&link_type=abstract
American Geophysical Union, Fall Meeting 2010, abstract #SM51C-1837
Physics
Plasma Physics
[2723] Magnetospheric Physics / Magnetic Reconnection, [7526] Solar Physics, Astrophysics, And Astronomy / Magnetic Reconnection, [7835] Space Plasma Physics / Magnetic Reconnection, [7863] Space Plasma Physics / Turbulence
Scientific paper
One of the key open questions in magnetic reconnection is the nature of the mechanism that governs the reconnection rate in real astrophysical and laboratory systems. Comparisons between fully kinetic 2-D simulations of the Magnetic Reconnection Experiment (MRX) and experimental data indicate that three-dimensional dynamics, such as current layer disruptions recently observed in MRX, may play a key role in resolving an important discrepancy in the reconnection rate and layer width [1,2,3]. These disruptions are often associated with fluctuations in the lower hybrid frequency range and a rapid local reconnection rate. Fluctuations are observed not only in MRX [4], but also in space [5] and 3-D kinetic simulations. Comparison of fluctuation characteristics between the three domains may shed light on the underlying physics. In both the simulation and the experiments, the fluctuations are related to density gradients across the layer. The frequency range is similarly broadband up to the lower hybrid range, and the phase velocities are comparable in appropriately normalized units. However, while the electron drift speed is comparable to the phase velocity at the layer center in the experiment (consistent with previous MRX results [4]), the drift speed in the simulations is considerably larger. Furthermore, the fluctuations observed in the experiment are fully turbulent with correlation lengths the same order as the wavelength while those observed in the simulations and in space are more coherent. Some discharges also display "O-point" signatures consistent with magnetic island like structures. The present research explores the relationship between the disruptions and fluctuations in the context of the reconnection rate problem. Experiments are ongoing to determine what physics is responsible for the broader current layers (and correspondingly smaller drift speeds) observed in the experiment. [1] Y. Ren, et al., Phys. Plasmas 15, 082113 (2008). [2] S. Dorfman, et al., Phys. Plasmas 15, 102107 (2008). [3] V. Roytershteyn, et al., Phys. Plasmas 17, 055706 (2010). [4] H. Ji, et al., Phys.Rev.Lett. 92, 115001 (2004). [5] S. Bale, et al., Geophys. Res. Lett., 29, 2180 (2002).
Daughton W. S.
Dorfman S. E.
Ji Hantao
Lawrence E. E.
Myers Chris
No associations
LandOfFree
Study of Lower Hybrid Frequency Turbulence in the Magnetic Reconnection Experiment (MRX) does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Study of Lower Hybrid Frequency Turbulence in the Magnetic Reconnection Experiment (MRX), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Study of Lower Hybrid Frequency Turbulence in the Magnetic Reconnection Experiment (MRX) will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1474377