Author: Qiang, J.
Paper Title Page
SAPLG01 Advances in Simulation of High Brightness/High Intensity Beams 1
 
  • J. Qiang
    LBNL, Berkeley, California, USA
 
  High brightness/high intensity beams play an important role in accelerator based applications by driving x-ray free electron laser (FEL) radiation, producing spallation neutrons and neutrinos, and generating new particles in high energy colliders. In this paper, we report on recent advances in modeling the high brightness electron beam with application to the next generation FEL light sources and in modeling space-charge effects in high intensity proton accelerators.  
slides icon Slides SAPLG01 [3.914 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-SAPLG01  
About • paper received ※ 02 November 2018       paper accepted ※ 19 November 2018       issue date ※ 26 January 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
SUPAG06 Simulation Challenges for eRHIC Beam-Beam Study 99
 
  • Y. Luo
    BNL, Upton, Long Island, New York, USA
  • Y. Hao
    FRIB, East Lansing, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
  • Y. Roblin
    JLab, Newport News, Virginia, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The 2015 Nuclear Science Advisory Committee Long Rang Plan identified the need for an electron-ion collider facility as a gluon microscope with capabilities beyond those of any existing accelerator complex. To reach the required high energy, high luminosity, and high polarization, the eRHIC design based on the existing heady ion and polarized proton collider RHIC adopts a very small beta-function at the interaction point, a high collision repetition rate, and a novel hadron cooling scheme. Collision with a full crossing angle of 22 mrad and crab cavities for both electron and proton rings are required. In this article, we will present the high priority R&D items related to beam-beam interaction for the current eRHIC design, the simulation challenges, and our plans to address them.
 
slides icon Slides SUPAG06 [2.395 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-SUPAG06  
About • paper received ※ 18 October 2018       paper accepted ※ 03 December 2018       issue date ※ 26 January 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPAF22 FEL Simulation Using the Lie Method 240
 
  • K. Hwang, J. Qiang
    LBNL, Berkeley, California, USA
 
  Funding: U.S. Department of Energy under Contract No. DE-AC02-05CH11231
Advances in numerical methods for free-electron-laser~(FEL) simulation under wiggler period averaging~(WPA) are presented. First, WPA is generalized using perturbation Lie map method. The conventional WPA is identified as the leading order contribution. Next, a widely used shot-noise modeling method is improved along with a particle migration scheme across the numerical mesh. The artificial shot noise arising from particle migration is suppressed. The improved model also allows using arbitrary mesh size, slippage resolution, and integration step size. These advances will improve modeling of longitudinal beam profile evolution for fast FEL simulation.
 
slides icon Slides TUPAF22 [2.245 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAF22  
About • paper received ※ 17 October 2018       paper accepted ※ 28 January 2019       issue date ※ 26 January 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPLG01 Analysis of Emittance Growth in a Gridless Spectral Poisson Solver for Fully Symplectic Multiparticle Tracking 335
 
  • C.E. Mitchell, J. Qiang
    LBNL, Berkeley, California, USA
 
  Funding: This work was supported by the Director, Office of Science, Office of High Energy Physics, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
Gridless spectral methods for self-consistent symplectic space charge modeling possess several advantages over traditional momentum-conserving particle-in-cell methods, including the absence of numerical grid heating and the presence of an underlying multi-particle Hamiltonian. Nevertheless, evidence of collisional particle noise remains. For a class of such 1D and 2D algorithms, we provide analytical models of the numerical field error, the optimal choice of spectral modes, and the numerical emittance growth per timestep. We compare these results with the emittance growth models of Struckmeier, Hoffman, Kesting, and others.
 
slides icon Slides WEPLG01 [11.804 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-WEPLG01  
About • paper received ※ 18 October 2018       paper accepted ※ 28 January 2019       issue date ※ 26 January 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)