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Full-Text Articles in Physics
Magnetic Field Amplification In Electron Phase-Space Holes And Related Effects, R. A. Treumann, W. Baumjohann
Magnetic Field Amplification In Electron Phase-Space Holes And Related Effects, R. A. Treumann, W. Baumjohann
Dartmouth Scholarship
No abstract provided.
The Role Of The Bow Shock In Solar Wind-Magnetosphere Coupling, R E. Lopez, V G. Merkin, J G. Lyon
The Role Of The Bow Shock In Solar Wind-Magnetosphere Coupling, R E. Lopez, V G. Merkin, J G. Lyon
Dartmouth Scholarship
No abstract provided.
Turbulence And Bias-Induced Flows In Simple Magnetized Toroidal Plasmas, B. Li, B. N. Rogers, P. Ricci, K. W. Gentle
Turbulence And Bias-Induced Flows In Simple Magnetized Toroidal Plasmas, B. Li, B. N. Rogers, P. Ricci, K. W. Gentle
Dartmouth Scholarship
Turbulence and bias-induced flows in simple magnetized toroidal plasmas are explored with global three- dimensional fluid simulations, focusing on the parameters of the Helimak experiment. The simulations show that plasma turbulence and transport in the regime of interest are dominated by the ideal interchange instability. The application of a bias voltage alters the structure of the plasma potential, resulting in the equilibrium sheared flows. These bias-induced vertical flows located in the gradient region appear to reduce the radial extent of turbulent structures, and thereby lower the radial plasma transport on the low field side.
Resistive Mhd Reconstruction Of Two-Dimensional Coherent Structures In Space, W L. Teh, B U. Sonnerup, J Birn, R E. Denton
Resistive Mhd Reconstruction Of Two-Dimensional Coherent Structures In Space, W L. Teh, B U. Sonnerup, J Birn, R E. Denton
Dartmouth Scholarship
We present a reconstruction technique to solve the steady resistive MHD equations in two dimensions with initial inputs of field and plasma data from a single space- craft as it passes through a coherent structure in space. At least two components of directly measured electric fields (the spacecraft spin-plane components) are required for the reconstruction, to produce two-dimensional (2-D) field and plasma maps of the cross section of the structure. For con- venience, the resistivity tensor η is assumed diagonal in the reconstruction coordinates, which allows its values to be es- timated from Ohm’s law, E+v×B=η·j. In the present paper, …
Hydrodynamic Relaxation Of An Electron Plasma To A Near-Maximum Entropy State, D. J. Rodgers, S. Servidio, W. H. Matthaeus, D. C. Montgomery, T. B. Mitchell, T. Aziz
Hydrodynamic Relaxation Of An Electron Plasma To A Near-Maximum Entropy State, D. J. Rodgers, S. Servidio, W. H. Matthaeus, D. C. Montgomery, T. B. Mitchell, T. Aziz
Dartmouth Scholarship
Dynamical relaxation of a pure electron plasma in a Malmberg-Penning trap is studied, comparing experiments, numerical simulations and statistical theories of weakly dissipative two-dimensional (2D) turbulence. Simulations confirm that the dynamics are approximated well by a 2D hydrodynamic model. Statistical analysis favors a theoretical picture of relaxation to a near-maximum entropy state with constrained energy, circulation, and angular momentum. This provides evidence that 2D electron fluid relaxation in a turbulent regime is governed by principles of maximum entropy.
Comparative Investigations Of Equatorial Electrodynamics And Low-To-Mid Latitude Coupling Of The Thermosphere-Ionosphere System, M J. Colerico, M Mendillo, C G. Fesen, J Meriwether
Comparative Investigations Of Equatorial Electrodynamics And Low-To-Mid Latitude Coupling Of The Thermosphere-Ionosphere System, M J. Colerico, M Mendillo, C G. Fesen, J Meriwether
Dartmouth Scholarship
The thermospheric midnight temperature maxi-
mum (MTM) is a highly variable, but persistent, large scale
neutral temperature enhancement which occurs at low lati-
tudes. Its occurrence can impact many fundamental upper
atmospheric parameters such as pressure, density, neutral
winds, neutral density, and F-region plasma. Although the
MTM has been the focus of several investigations employ-
ing various instrumentation including photometers, satellites,
and Fabry-Perot interferometers, limited knowledge exists
regarding the latitude extent of its influence on the upper at-
mosphere. This is largely due to observational limitations
which confined the collective geographic range to latitudes
within ±23◦. This paper investigates the …
The Structure Of Flux Transfer Events Recovered From Cluster Data, H Hasegawa, B U. Ö Sonnerup, C J. Owen, B Klecker, G Paschmann, A Balogh, H Re`Me
The Structure Of Flux Transfer Events Recovered From Cluster Data, H Hasegawa, B U. Ö Sonnerup, C J. Owen, B Klecker, G Paschmann, A Balogh, H Re`Me
Dartmouth Scholarship
The structure and formation mechanism of a to- tal of five Flux Transfer Events (FTEs), encountered on the equatorward side of the northern cusp by the Cluster space- craft, with separation of ∼5000 km, are studied by apply- ing the Grad-Shafranov (GS) reconstruction technique to the events. The technique generates a magnetic field/plasma map of the FTE cross section, using combined magnetic field and plasma data from all four spacecraft, under the assump- tion that the structure is two-dimensional (2-D) and time- independent. The reconstructed FTEs consist of one or more magnetic flux ropes embedded in the magnetopause, suggest- ing …
Optimal Reconstruction Of Magnetopause Structures From Cluster Data, H Hasegawa, B U. Ö Sonnerup, B Klecker, G Paschmann
Optimal Reconstruction Of Magnetopause Structures From Cluster Data, H Hasegawa, B U. Ö Sonnerup, B Klecker, G Paschmann
Dartmouth Scholarship
The Grad-Shafranov (GS) reconstruction tech- nique, a single-spacecraft based data analysis method for recovering approximately two-dimensional (2-D) magneto- hydrostatic plasma/field structures in space, is improved to become a multi-spacecraft technique that produces a single field map by ingesting data from all four Cluster spacecraft into the calculation. The plasma pressure, required for the technique, is measured in high time resolution by only two of the spacecraft, C1 and C3, but, with the help of spacecraft po- tential measurements available from all four spacecraft, the pressure can be estimated at the other spacecraft as well via a relationship, established from C1 …