A numerical method is described for producing stationary solutions of the Vlasov-Poisson system describing a relativistic charged-particle beam in a constant focusing accelerator channel, confined transversely by a general (linear or nonlinear) focusing potential. The method utilizes a variant of the spectral Galerkin algorithm to solve a nonlinear partial differential equation (PDE) in two degrees of freedom for the beam space charge potential in equilibrium. Numerical convergence with an increasing number of computed spectral modes is investigated for several benchmark problems. Preservation of the stationary phase space density is verified using a strongly nonlinear focusing channel based on the Integrable Optics Test Accelerator at Fermi National Accelerator Laboratory.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevE.100.053308 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Block diagonal Calderón preconditioning for scattering at multi-screens.
BIT Numer Math
September 2024
Mekelweg 6, 2628 CD Delft, The Netherlands.
A preconditioner is proposed for Laplace exterior boundary value problems on multi-screens. To achieve this, the quotient-space boundary element method and operator preconditioning are combined. For a fairly general subclass of multi-screens, it is shown that this approach paves the way for block diagonal Calderón preconditioners which achieve a spectral condition number that grows only logarithmically with decreasing mesh size, just as in the case of simple screens.
View Article and Find Full Text PDFSpectral Galerkin mode-matching method for applications in photonics.
Phys Rev E
May 2024
Department of Mathematics, City University of Hong Kong, Kowloon, Hong Kong, China.
Many engineered photonic devices can be decomposed into parts where the material properties are independent of one or more spatial variables. Numerical mode-matching methods are widely used to simulate such photonic devices due to the efficiency gained by treating the separated variables analytically. Existing mode-matching methods based on piecewise polynomials are more accurate than those based on the global Fourier basis or low-order finite difference, finite-element schemes, but they may exhibit numerical instability when a large number of eigenmodes are used.
View Article and Find Full Text PDFNumerical study of the scattering of acoustic waves by an elliptic vortex.
J Acoust Soc Am
March 2024
Laboratoire d'Acoustique de l'Université du Mans (LAUM), UMR 6613, Institut d'Acoustique - Graduate School (IA-GS), CNRS, Le Mans Université, Le Mans 72000, France.
The scattering of the acoustic waves generated by a monopolar source propagating through a two-dimensional elliptic vortex, fixed or convected by a uniform flow, is studied by solving the Linearized Euler Equations in Cartesian coordinates using the Discontinuous Galerkin Method. For a fixed vortex position, the number, amplitudes, and angular spreads of the acoustic interference beams resulting from the sound scattering are found to significantly depend on the orientation of the vortex major axis with respect to the direction of the incident waves and on the vortex maximum tangential velocity. In particular, additional interference beams are obtained at large observation angles for a more elliptical vortex.
View Article and Find Full Text PDFThe Effect of Nanoparticle Composition on the Surface-Enhanced Raman Scattering Performance of Plasmonic DNA Origami Nanoantennas.
ACS Nano
November 2023
Hybrid Nanostructures Lab, Institute of Chemistry, University of Potsdam, 14476 Potsdam, Germany.
A versatile generation of plasmonic nanoparticle dimers for surface-enhanced Raman scattering (SERS) is presented by combining a DNA origami nanofork and spherical and nonspherical Au or Ag nanoparticles. Combining different nanoparticle species with a DNA origami nanofork to form DNA origami nanoantennas (DONAs), the plasmonic nanoparticle dimers can be optimized for a specific excitation wavelength in SERS. The preparation of such nanoparticle dimers is robust enough to enable the characterization of SERS intensities and SERS enhancement factors of dye-modified DONAs on a single dimer level by measuring in total several thousands of dimers from five different dimer designs, each functionalized with three different Raman reporter molecules and measured at four different excitation wavelengths.
View Article and Find Full Text PDFSome approximation results for mild solutions of stochastic fractional order evolution equations driven by Gaussian noise.
Stoch Partial Differ Equ
April 2022
Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary.
We investigate the quality of space approximation of a class of stochastic integral equations of convolution type with Gaussian noise. Such equations arise, for example, when considering mild solutions of stochastic fractional order partial differential equations but also when considering mild solutions of classical stochastic partial differential equations. The key requirement for the equations is a smoothing property of the deterministic evolution operator which is typical in parabolic type problems.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!