Current and future accelerator design requires efficient 3D space charge computations for high brightness bunches which should be as precise and fast as possible. One possible approach for space charge calculations is the particle-mesh-method, where the potential is calculated in the rest frame of the bunch by means of Poisson’s equation. For an efficient solution of this elliptic PDE an approp...

We present a hybrid finite-volume-particle numerical method for computing the transport of a passive pollutant by a flow. The flow is modeled by the oneand two-dimensional Saint-Venant system of shallow water equations and the pollutant propagation is described by a transport equation. This paper is an extension of our previous work [Chertock, Kurganov and Petrova, J. Sci. Comput. (to appear)],...

Simulation of Pollutant Transport Using a Particle Method S. Zimmermann,∗ P. Koumoutsakos,† and W. Kinzelbach∗ ∗Institute of Hydromechanics and Water Resources Management (IHW), ETH Hönggerberg, Zürich CH-8093, Switzerland; and †Institute of Computational Sciences, ETH, Zürich CH-8092, Switzerland, and CTR, NASA Ames 202A-1, Moffett Field, California 94035 E-mail: [email protected], p...

Motivated by biological ion channels, we develop a new multiscale method for interacting particle systems coupling a particle and a continuum model. The method aims at the computation of particle interactions on the molecular scale and therefore incorporates particle correlations induced by short and long range interactions. To construct the multiscale method we use a stochastic particle model ...

Existing widely used pileup removal approaches correct the momenta of individual jets. In this article we introduce an event-level, particle-based pileup correction procedure, SoftKiller. It removes the softest particles in an event, up to a transverse momentum threshold that is determined dynamically on an event-by-event basis. In simulations, this simple procedure appears to be reasonably rob...

Graphics Processing Units (GPUs), originally developed for computer games, now provide computational power for scientific applications. A study on the comparison of computational speed-up and efficiency of a GPU with a CPU for the Finite Pointset Method (FPM), which is a numerical tool in Computational Fluid Dynamics (CFD) is presented. As FPM is based on the point cloud, it is so expensive whe...

We explore the gap-tooth method for multiscale modeling of systems represented by microscopic physics-based simulators, when coarse-grained evolution equations are not available in closed form. A biased random walk particle simulation, motivated by the viscous Burgers equation, serves as an example. We construct macro-to-micro (lifting) and micro-to-macro (restriction) operators, and drive the ...

In recent years Sequential Monte Carlo (SMC) methods have been applied to handle some of the problems inherent to model-based tracking. In this paper two issues regarding SMC are investigated in the context of estimating the 3D pose of the human arm. Firstly, we investigate how to apply a sub-space to representing the pose of a human arm more efficiently, i.e., reducing the dimensionality. Seco...