IPAC2015 - List of Keywords (electromagnetic-fields)

Paper	Title	Other Keywords	Page
MOPMN012	SPACE Code for Beam-Plasma Interaction	plasma, simulation, ion, electron	728
	K. Yu, V. Samulyak SBU, Stony Brook, USA V. Samulyak BNL, Upton, Long Island, New York, USA
	A parallel particle-in-cell code SPACE has been developed for the simulation of electromagnetic fields, relativistic particle beams, and plasmas. The algorithms include atomic processes in the plasma, proper boundary conditions, an efficient method for highly-relativistic beams in non-relativistic plasma, support for simulations in relativistic moving frames, and special data transfer algorithm from the moving to the laboratory frame that collects particles and fields in the lab frame without time shift due to the Lorentz transform, enabling data analysis and visualization. Plasma chemistry algorithms implement atomic physics processes such as the generation and evolution of plasma, recombination of plasma, and electron attachment on dopants in dense neutral gas. Benchmarks and experimental validation tests are also discussed. The code has been used for the simulation of processes relevant to the eRHIC program at BNL and the high pressure RF cavity (HPRF) program at Fermilab.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPMN012
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MOPTY036	Radiation of a Bunch Moving in the Presence of a Bounded Planar Wire Structure	radiation, vacuum, diagnostics, electronics	1007
	V.V. Vorobev, S.N. Galyamin, A.A. Grigoreva, A.V. Tyukhtin Saint-Petersburg State University, Saint-Petersburg, Russia
	Three-dimensional* and planar periodic structures can be used for non-destructive diagnostics of charged particle bunches. Here we consider the semi-infinite planar structure comprised of thin conducting parallel wires. If the period of the structure is much less than the typical wavelength of the electromagnetic field, then the structure's influence can be described with help of the averaged boundary conditions. We study radiation of a charged particle bunch with small transversal size and arbitrary longitudinal one in two cases: (i) the bunch moves orthogonally to the grid at some distance from the edge and (ii) it moves along the edge of the grid. The problems are solved analytically. In both cases the bunch generates a surface wave which contains the information about the size of the bunch. The shape of the surface waves is similar to the radiation generated in the presence of 3D periodical wire structures, however planar structure is simpler for use in accelerating system. Some typical numerical results for bunches of various shapes are given. * V.V. Vorobev et al., Phys. Rev. Let., 108, 184801 (2012); A.V. Tyukhtin et al., Phys. Rev. ST AB (in press). * M.I. Kontorovich et al., Electrodynamics of Grid Structures (Moscow, 1987).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPTY036
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WEPMN010	Analysis of the Electromagnetic Field in the Coupler of Normal Temperature Travelling-Wave Accelerating Tube	coupling, cavity, emittance, simulation	2934
	X. He, M. Hou IHEP, Beijing, People's Republic of China S. Shu Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing, People's Republic of China
	With the developed requirement of the beam quality in modern accelerators, rapid development of all kinds of accelerating structures with different frequencies and materials have been achieved. However, the normal temperature travelling-wave (TW) accelerating structures which are widely used in Free Electron Laser (FEL) are still indispensable. For reducing the beam emittance, it is very important to optimize the symmetry of the high-order electromagnetic field in the coupler of such accelerating structures. In this paper, the symmetry of the electromagnetic field in TW accelerator couplers using different coupling mechanisms was analysed. A lot of design optimization as well as the result analysis work has been done for the three kinds of commonly used waveguide-coupled TW accelerating structures: single-feed electrical-coupling, dual-feed electrical-coupling using magic tee in feeding waveguide and dual-feed magnetic-coupling using J-type feeding waveguide. Finally, basing on lots of simulation results and the performances during the fabrication, measurement and RF conditioning of these three kinds of structures, the J-type racetrack coupler type is regarded as the best choice.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMN010
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WEPMN014	A C-band Deflecting Cavity Design for High-precision Bunch Length Measurement	cavity, simulation, electron, coupling	2948
	J. Jiang, H.B. Chen, J. Shi, P. Wang TUB, Beijing, People's Republic of China
	Funding: NSFC 11375098 and 11327902 A standing wave RF deflecting structure has been designed as a tool for high-precision bunch length measurement. This 3-cell deflecting cavity is designed to operate at a frequency of 5.712GHz. In this paper, the RF design and thermal analysis of the deflecting cavity are introduced. We study the electromagnetic field distribution inside the cavity. The coupler design is also discussed. And the beam dynamics simulation is shown.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMN014
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Paper

Title

Other Keywords

Page

MOPMN012

SPACE Code for Beam-Plasma Interaction

plasma, simulation, ion, electron

728

K. Yu, V. Samulyak
SBU, Stony Brook, USA
V. Samulyak
BNL, Upton, Long Island, New York, USA

A parallel particle-in-cell code SPACE has been developed for the simulation of electromagnetic fields, relativistic particle beams, and plasmas. The algorithms include atomic processes in the plasma, proper boundary conditions, an efficient method for highly-relativistic beams in non-relativistic plasma, support for simulations in relativistic moving frames, and special data transfer algorithm from the moving to the laboratory frame that collects particles and fields in the lab frame without time shift due to the Lorentz transform, enabling data analysis and visualization. Plasma chemistry algorithms implement atomic physics processes such as the generation and evolution of plasma, recombination of plasma, and electron attachment on dopants in dense neutral gas. Benchmarks and experimental validation tests are also discussed. The code has been used for the simulation of processes relevant to the eRHIC program at BNL and the high pressure RF cavity (HPRF) program at Fermilab.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPMN012

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MOPTY036

Radiation of a Bunch Moving in the Presence of a Bounded Planar Wire Structure

radiation, vacuum, diagnostics, electronics

1007

V.V. Vorobev, S.N. Galyamin, A.A. Grigoreva, A.V. Tyukhtin
Saint-Petersburg State University, Saint-Petersburg, Russia

Three-dimensional* and planar** periodic structures can be used for non-destructive diagnostics of charged particle bunches. Here we consider the semi-infinite planar structure comprised of thin conducting parallel wires. If the period of the structure is much less than the typical wavelength of the electromagnetic field, then the structure's influence can be described with help of the averaged boundary conditions***. We study radiation of a charged particle bunch with small transversal size and arbitrary longitudinal one in two cases: (i) the bunch moves orthogonally to the grid at some distance from the edge and (ii) it moves along the edge of the grid. The problems are solved analytically. In both cases the bunch generates a surface wave which contains the information about the size of the bunch. The shape of the surface waves is similar to the radiation generated in the presence of 3D periodical wire structures*, however planar structure is simpler for use in accelerating system. Some typical numerical results for bunches of various shapes are given.
* V.V. Vorobev et al., Phys. Rev. Let., 108, 184801 (2012);
** A.V. Tyukhtin et al., Phys. Rev. ST AB (in press).
*** M.I. Kontorovich et al., Electrodynamics of Grid Structures (Moscow, 1987).

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPTY036

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WEPMN010

Analysis of the Electromagnetic Field in the Coupler of Normal Temperature Travelling-Wave Accelerating Tube

coupling, cavity, emittance, simulation

2934

X. He, M. Hou
IHEP, Beijing, People's Republic of China
S. Shu
Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing, People's Republic of China

With the developed requirement of the beam quality in modern accelerators, rapid development of all kinds of accelerating structures with different frequencies and materials have been achieved. However, the normal temperature travelling-wave (TW) accelerating structures which are widely used in Free Electron Laser (FEL) are still indispensable. For reducing the beam emittance, it is very important to optimize the symmetry of the high-order electromagnetic field in the coupler of such accelerating structures. In this paper, the symmetry of the electromagnetic field in TW accelerator couplers using different coupling mechanisms was analysed. A lot of design optimization as well as the result analysis work has been done for the three kinds of commonly used waveguide-coupled TW accelerating structures: single-feed electrical-coupling, dual-feed electrical-coupling using magic tee in feeding waveguide and dual-feed magnetic-coupling using J-type feeding waveguide. Finally, basing on lots of simulation results and the performances during the fabrication, measurement and RF conditioning of these three kinds of structures, the J-type racetrack coupler type is regarded as the best choice.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMN010

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMN014

A C-band Deflecting Cavity Design for High-precision Bunch Length Measurement

cavity, simulation, electron, coupling

2948

J. Jiang, H.B. Chen, J. Shi, P. Wang
TUB, Beijing, People's Republic of China

Funding: NSFC 11375098 and 11327902
A standing wave RF deflecting structure has been designed as a tool for high-precision bunch length measurement. This 3-cell deflecting cavity is designed to operate at a frequency of 5.712GHz. In this paper, the RF design and thermal analysis of the deflecting cavity are introduced. We study the electromagnetic field distribution inside the cavity. The coupler design is also discussed. And the beam dynamics simulation is shown.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMN014

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)