Single-particle orbit equation in crystalline beams

AbstractCurrent sheets are ubiquitous plasma structures that play the crucial role of being energy sources for various magnetic phenomena. Although a plethora of current sheet equilibrium solutions have been found, the collisionless process through which a disequilibrated current sheet relaxes or equilibrates remains largely unknown. Here we show, through analyses of phase-space distributions of single-particle orbit classes and particle-in-cell simulations, that collisionless transitions among the orbit classes are responsible for this process. Bifurcated current sheets, which are readily observed in geospace but whose origins remain controversial, are shown to naturally arise from the equilibration process and thus are likely to be the underlying structures in various phenomena; comparisons of spacecraft observations to particle-in-cell simulations support this fact. The bearing of this result on previous explanations of bifurcated structures is also discussed.

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Toroidal current initiation in low aspect ratio tokamaks based on single-particle orbit analysis

Nuclear Fusion ◽

10.1088/0029-5515/47/5/005 ◽

2007 ◽

Vol 47 (5) ◽

pp. 403-416 ◽

Cited By ~ 19

Author(s):

A Ejiri ◽

Y Takase

Keyword(s):

Aspect Ratio ◽

Single Particle ◽

Low Aspect Ratio ◽

Particle Orbit ◽

Orbit Analysis

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Coupling of a j = 3/2 nucleon to an even–even core with Davidson potential

International Journal of Modern Physics E ◽

10.1142/s0218301318500854 ◽

2018 ◽

Vol 27 (10) ◽

pp. 1850085 ◽

Cited By ~ 5

Author(s):

I. Inci ◽

H. Sonkaya

Keyword(s):

Experimental Data ◽

Energy Spectrum ◽

Excitation Energy ◽

Single Particle ◽

Electric Quadrupole ◽

Quadrupole Transition ◽

Excitation Energy Spectrum ◽

Electric Quadrupole Transition ◽

Particle Orbit ◽

Davidson Potential

The properties of odd nuclei have been investigated within the collective model by assuming the system is composed of a single nucleon in the [Formula: see text] single particle orbit coupled to a [Formula: see text]-unstable even-core. The Davidson potential has been used in the corresponding Bohr Hamiltonian for the even core. The excitation energy spectrum and the electric quadrupole transition ratios have been obtained. The results have been used to predict the experimental data of the some selected odd isotopes.

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Collisionless Relaxation of a Disequilibrated Current Sheet and Implications for Bifurcated Structures

10.21203/rs.3.rs-343769/v1 ◽

2021 ◽

Author(s):

Young Dae Yoon ◽

Gunsu Yun ◽

James Burch ◽

Deirdre Wendel

Keyword(s):

Phase Space ◽

Current Sheet ◽

Single Particle ◽

Energy Sources ◽

Equilibrium Solutions ◽

Current Sheets ◽

Particle In Cell ◽

Particle Orbit ◽

Equilibration Process

Abstract Current sheets are ubiquitous plasma structures that play the crucial role of being energy sources for various magnetic phenomena. Although a plethora of current sheet equilibrium solutions have been found, the collisionless process through which a disequilibrated current sheet relaxes or equilibrates remains largely unknown. Here we show, through analyses of phase-space distributions of single-particle orbit classes and particle-in-cell simulations, that collisionless transitions among the orbit classes are responsible for this process. Bifurcated current sheets, which are readily observed in geospace but whose origins remain controversial, are shown to naturally arise from the equilibration process and thus are likely to be the underlying structures in various phenomena; comparisons of spacecraft observations to particle-in-cell simulations support this fact. The bearing of this result on previous explanations of bifurcated structures is also discussed.

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Localization of immunolabels by electron microscopy and image averaging

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075208 ◽

1983 ◽

Vol 41 ◽

pp. 282-283

Author(s):

J. Frank ◽

P.-Y. Sizaret ◽

A. Verschoor ◽

J. Lamy

Keyword(s):

Electron Microscopy ◽

Single Particle ◽

Attachment Site ◽

Uranyl Acetate ◽

Limulus Polyphemus ◽

Resolution Limit ◽

Electron Microscopic ◽

Image Averaging ◽

Top View ◽

Better Than

The accuracy with which the attachment site of immunolabels bound to macromolecules may be localized in electron microscopic images can be considerably improved by using single particle averaging. The example studied in this work showed that the accuracy may be better than the resolution limit imposed by negative staining (∽2nm).The structure used for this demonstration was a halfmolecule of Limulus polyphemus (LP) hemocyanin, consisting of 24 subunits grouped into four hexamers. The top view of this structure was previously studied by image averaging and correspondence analysis. It was found to vary according to the flip or flop position of the molecule, and to the stain imbalance between diagonally opposed hexamers (“rocking effect”). These findings have recently been incorporated into a model of the full 8 × 6 molecule.LP hemocyanin contains eight different polypeptides, and antibodies specific for one, LP II, were used. Uranyl acetate was used as stain. A total of 58 molecule images (29 unlabelled, 29 labelled with antl-LPII Fab) showing the top view were digitized in the microdensitometer with a sampling distance of 50μ corresponding to 6.25nm.

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