Results 271 to 280 of about 20,337 (305)

Energy spread in ion beam analysis

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2000
Abstract In ion beam analysis (IBA) the depth profiles are extracted from the experimentally determined energy profiles. The spectra, however, are subject to finite energy resolution of both extrinsic and intrinsic origin. Calculation of those effects such as instrumental beam, geometry and detection-related energy and angular spreads as well as ...
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Creating a spread-out Bragg peak in proton beams

Physics in Medicine and Biology, 2011
The model of Bortfeld and Schlegel (1996 Phys. Med. Biol. 41 1331-9) for determining the weights of proton beams required to create a spread-out Bragg peak (SOBP) gives a significantly tilted SOBP. However, by arbitrarily varying its parameter p, which relates the range of protons to their energy, we have been able to create satisfactory SOBPs.
David, Jette, Weimin, Chen
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Beam spread and the Heisenberg uncertainty principle

Journal of the Franklin Institute, 1974
Abstract Modern highly directive radiating structures approach the ultimate minimum beam spread angle and maximum Rayleigh range predicted by the Heisenberg uncertainty principle.
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Analytic beam spread function for ocean optics applications

Applied Optics, 2002
A discrete ordinates code is developed with which to compute the beam spread function (BSF) without invoking the small-angle scattering approximation or performing Monte Carlo calculations. The computed BSF is used to predict the response of a detector versus its distance to the origin of a highly collimated beam, its angle with respect to the beam ...
Richard, Sanchez, Norman J, McCormick
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Gyrotron Electron Beams: Velocity and Energy Spread and Beam Instabilities

International Journal of Infrared and Millimeter Waves, 2001
The stability of the electron beams and maximum share of the electrons oscillatory energy, i.e. finally efficiency, power, and pulse duration of the gyrotron to a considerable extent depend on the velocity and the energy spread (VESP) of the HEB. The basic factors determining VESP in the helical beams are discussed.
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Theory of explosive beam spreading due to ray chaos

The Journal of the Acoustical Society of America, 2003
In an ocean acoustic situation where rays are known to be chaotic, a theory based on a Gaussian beam approximation is used to show that the width of a narrow-angle beam increases exponentially (explosively) with range at a rate that is given by the Lyapunov exponent that is calculated in the geometric limit.
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Effects of anisotropic turbulence on the long term beam spread and beam wander of Gaussian beam

Optik, 2018
Abstract Experiments and theoretical investigations have shown that the isotropic turbulence is not the only possible turbulence in the atmosphere. Researches about the anisotropic non-Kolmogorov have attracted more and more attentions recently.
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Lasersatcom: Mean Irradiance and Beam Spreading

2009
This excerpt gives a succinct explanation of Lasersatcom: Mean Irradiance and Beam Spreading.
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Head-on and long-range beam-beam tune shift spread in the SSC

Proceedings of International Conference on Particle Accelerators, 2002
The head-on and long-range incoherent tune shifts for the Superconducting Super Collider (SSC) are estimated using the numerical integration of the analytical expression coming from the first order in the perturbation strength. The variation of the tune shift as a function of the displacements of the charged particle in the vertical and horizontal ...
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Methods for Spreading Laser Beams

Applied Optics, 1971
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