PERFORMANCE ANALYSIS OF LEADING HPC ARCHITECTURES WITH (2009)
Hongzhang Shan, Erich Strohmaier, Ji Qiang, Hongzhang Shan, Erich Strohmaier, Ji Qiang
High energy colliders are essential to study the inner structure of nuclear and elementary particles. A parallel particle simulation code, BeamBeam3D, has been developed and actively used to model...
Numerical Study of Coulomb Scattering Effects on Electron Beam from a Nano-Tip (2008)
Qiang, Ji, Corlett, John N., Lidia, Steven M., Padmore, Howard A., Wan, Weishi, Zholent, Andrew A., ...
Juvenile Birds from the Early Cretaceous of China: Implications for Enantiornithine Ontogeny (2007)
LUIS M. CHIAPPE, JI SHU'AN, JI QIANG
Mesozoic remains of embryonic and early juvenile birds are rare. To date, a handful of in ovo embryos and early juveniles of enantiornithines from the Early Cretaceous of China and Spain and the Late...
Pogorelov, Ilya, Qiang, Ji, Ryne, Rob, Venturini, Marco, Zholents, Alexander, Warnock, Robert
In this paper, we examine the growth of the microbunching instability in the electron beam delivery system of a free electron laser (FEL). We present the results of two sets of simulations, one...
Performance Modeling and Optimization of a High Energy Colliding Beam Simulation Code (2006)
Shan, Hongzhang, Strohmaier, Erich, Qiang, Ji, Bailey, David H., Yelick, Kathy
Performance modeling and optimization of a high energy colliding beam simulation code (2006)
Hongzhang Shan, Erich Strohmaier, Ji Qiang, David H. Bailey, Kathy Yelick
An accurate modeling of the beam-beam interaction is essential to maximizing the luminosity in existing and future colliders. BeamBeam3D was the first parallel code that can be used to study this...
A Three-Dimensional Quasi-Static Model for High Brightness Beam Dynamics Simulation (2005)
Qiang, Ji, Lidia, Steve, Ryne, Robert D., Limborg-Deprey, Cecile
In this paper, we present a three-dimensional quasistatic model for high brightness beam dynamics simulation in rf/dc photoinjectors, rf linacs, and similar devices on parallel computers. In this...
Recent advances of strong-strong beam-beam simulation (2004)
Qiang, Ji, Furman, Miguel A., Ryne, Robert D., Fischer, Wolfram, Ohmi, Kazuhito
In this paper, we report on recent advances in strong-strong beam-beam simulation. Numerical methods used in the calculation of the beam-beam forces are reviewed. A new computational method to solve...
Strong-strong beam-beam simulation on parallel computer (2004)
The beam-beam interaction puts a strong limit on the luminosity of the high energy storage ring colliders. At the interaction points, the electromagnetic fields generated by one beam focus or defocus...
Qiang, Ji, Gluckstern, Robert L.
In this paper, we present a three-dimensional Poisson equation solver for the electrostatic potential of a charged beam with large longitudinal to transverse aspect ratio in a straight and a bent...
Qiang, Ji, Furman, Miguel, Ryne, Robert D., Fischer, Wolfram, Sen, Tanaji, Xiao, Meiqin
In this paper, we present a parallel computational tool, BeamBeam3D, developed at Lawrence Berkeley National Laboratory, for strong-strong/strong-weak beam-beam modeling. This tool calculates...
Wangler, Thomas P., Crandall, Kenneth R., Garnett, Robert W., Gorelov, Dmitry, Ostroumov, Petr, Qiang, Ji, ...
Advanced Beam-Dynamics Simulation Tools for the RIA Driver Linac; Low Energy Beam Transport and Radiofrequency Quadrupole
Halo formation from mismatched beam-beam interactions (2003)
In this paper, we report on the halo formation and emittance growth driven by a parametric resonance during mismatched beam-beam collisions. In the regime of the weak-strong beam-beam interaction, if...
Macroparticle simulations of antiproton lifetime at 150 GeV in the te vatron (2003)
Qiang, Ji, Ryne, Robert D., Sen, Tanaji, Xiao, Meiqin
In this paper we report on a systematic study of antiproton lifetime at the injection energy of 150 GeV in the Tevatron. Our parallel beam-beam model can handle both strong-strong and weak-strong...
New Specimens of Microraptor zhaoianus (Theropoda: Dromaeosauridae) from Northeastern China (2002)
SUNNY H. HWANG, MARK A. NORELL, JI QIANG, GAO KEQIN
New specimens of the diminutive theropod dinosaur Microraptor zhaoianus are described. These specimens preserve significant morphological details that are not present or are poorly preserved in the...
Parallel beam dynamics simulation of linear accelerators (2002)
In this paper we describe parallel particle-in-cell methods for the large scale simulation of beam dynamics in linear accelerators. These techniques have been implemented in the IMPACT (Integrated...
Interactive visualization of particle beams for accelerator design (2002)
Wilson, Brett, Ma, Kwan-Liu, Qiang, Ji, Ryne, Robert
We describe a hybrid data-representation and rendering technique for visualizing large-scale particle data generated from numerical modeling of beam dynamics. The basis of the technique is mixing...
In this paper we present results of using parallel supercomputers to simulate beam dynamics in next-generation high intensity ion linacs. Our approach uses a three-dimensional space charge...
EXCEPTIONAL FOSSIL MATERIAL OF A SEMI-AQUATIC REPTILE FROM CHINA: THE RESOLUTION OF AN ENIGMA (2000)
A Second-Order Stochastic Leap-Frog Algorithm for Langevin Simulation (2000)
Langevin simulation provides an effective way to study collisional effects in beams by reducing the six-dimensional Fokker-Planck equation to a group of stochastic ordinary differential equations....
A Second-Order Stochastic Leap-Frog Algorithm for Multiplicative Noise Brownian Motion (1999)
A stochastic leap-frog algorithm for the numerical integration of Brownian motion stochastic differential equations with multiplicative noise is proposed and tested. The algorithm has a second-order...
Calibration and application of a tokamak transport model in JT-60 /--by Ji Qiang. (1995)
Thesis (M.S.)--University of Illinois at Urbana-Champaign, 1995.