ICAP2012 - List of Keywords (undulator)

Paper	Title	Other Keywords	Page
TUACI1	Numerical Modeling of Collective Effects in Free Electron Laser	FEL, simulation, radiation, electron	81
	I. Zagorodnov DESY, Hamburg, Germany
	In order to have a free electron laser (FEL) of high performance we need to design and optimize it taking into account the dynamics of electrons and their interactions with each other and with their surroundings. An accurate self-consistent simulation of collective effects in the charged beams remains a challenging problem for numerical analysis. In this paper we consider only the modeling of FEL process in an undulator section. We give a short overview of the numerical methods adopted in different FEL codes. Advantages and drawbacks of these methods will be discussed. Some approaches to improve the accuracy and efficiency of the codes will be presented and the remaining challenges in FEL modeling will be highlighted.
	Slides TUACI1 [2.659 MB]

TUACC2	WAVE - A Computer Code for the Tracking of Electrons through Magnetic Fields and the Calculation of Spontaneous Synchrotron Radiation	electron, radiation, synchrotron, synchrotron-radiation	86
	M. Scheer HZB, Berlin, Germany
	WAVE has been developed since 1990 at BESSY - now Helmholtz-Zentrum Berlin (HZB) - to calculate spontaneous synchrotron radiation for arbitrary magnetic fields. A variety of field models for dipoles, wavelength shifters, and undulators is available. Field maps and tables can be read and written. Many routines to handle magnetic fields are implemented, including simulations of field error e.g. due to misalignment. Coherent radiation of electrons in a bunch and energy losses due to radiation are taken into account. Phase space distribution of electrons are taken into account by various algorithms. Generating functions and linear transfer matrices for particle tracking purposes can be calculated. Subroutines to calculate the effects of insertion devices on the storage ring are included. The program runs in batch mode, controlled by input files, but a simple GUI is also provided. The results are given as ASCII data or binary formats of the programs PAW, ROOT, and HDF5. Parallel runs of WAVE on a cluster are supported. WAVE has been checked and validated with the synchrotron radiation code of the German National Bureau of Standards (PTB) based on Schwinger's formula.
	Slides TUACC2 [3.685 MB]

TUSCC3	Undulator Radiation Inside a Dielectric Waveguide	radiation, vacuum, insertion, synchrotron	96
	A. Kotanjyan, A.A. Saharian YSU, Yerevan, Armenia
	We investigate the radiation from a charge moving along a helix around a dielectric cylinder immersed in a homogeneous medium. We are mainly concerned with the radiation propagating inside the cylinder. The radiation intensity for the modes propagating inside the cylinder is evaluated by the work done by the radiation field on the charge and by evaluating the energy flux through the cross-section of the cylinder. The insertion of a dielectric waveguide provides an additional mechanism for tuning the characteristics of the undulator radiation by choosing the parameters of the waveguide. The radiated energy inside the cylinder is redistributed among the cylinder modes, the corresponding spectrum differs significantly from the homogeneous medium or free-space results. This change is of special interest in the low-frequency range where the distribution of the radiation energy among small number of modes leads to the enhancement of the spectral density for the radiation intensity. The radiation emitted on the waveguide modes propagates inside the cylinder and the waveguide serves as a natural collector for the radiation.
	Slides TUSCC3 [0.809 MB]

FRSAC1	Hybrid Programming and Performance for Beam Propagation Modeling	simulation, wakefield, cavity	284
	M. Min, A. Mametjanov ANL, Argonne, USA J. Fu RPI, Troy, New York, USA
	Funding: DOE ASCR (Advanced Scientific Computing Research) Program We examined hybrid parallel infrastructures in order to ensure performance and scalability for beam propagation modeling as we move toward extreme-scale systems. Using an MPI programming interface for parallel algorithms, we expanded the capability of our existing electromagnetic solver to a hybrid (MPI/shared-memory) model that can potentially use the computer resources on future-generation computing architecture more efficiently. As a preliminary step, we discuss a hybrid MPI/OpenMP model and demonstrate performance and analysis on the leadership-class computing systems such as the IBM BG/P, BG/Q, and Cray XK6. Our hybrid MPI/OpenMP model achieves speedup when the computation amounts are large enough to compensate the OMP threading overhead.
	Slides FRSAC1 [4.252 MB]

Paper

Title

Other Keywords

Page

TUACI1

Numerical Modeling of Collective Effects in Free Electron Laser

FEL, simulation, radiation, electron

81

I. Zagorodnov
DESY, Hamburg, Germany

In order to have a free electron laser (FEL) of high performance we need to design and optimize it taking into account the dynamics of electrons and their interactions with each other and with their surroundings. An accurate self-consistent simulation of collective effects in the charged beams remains a challenging problem for numerical analysis. In this paper we consider only the modeling of FEL process in an undulator section. We give a short overview of the numerical methods adopted in different FEL codes. Advantages and drawbacks of these methods will be discussed. Some approaches to improve the accuracy and efficiency of the codes will be presented and the remaining challenges in FEL modeling will be highlighted.

Slides TUACI1 [2.659 MB]

TUACC2

WAVE - A Computer Code for the Tracking of Electrons through Magnetic Fields and the Calculation of Spontaneous Synchrotron Radiation

electron, radiation, synchrotron, synchrotron-radiation

86

M. Scheer
HZB, Berlin, Germany

WAVE has been developed since 1990 at BESSY - now Helmholtz-Zentrum Berlin (HZB) - to calculate spontaneous synchrotron radiation for arbitrary magnetic fields. A variety of field models for dipoles, wavelength shifters, and undulators is available. Field maps and tables can be read and written. Many routines to handle magnetic fields are implemented, including simulations of field error e.g. due to misalignment. Coherent radiation of electrons in a bunch and energy losses due to radiation are taken into account. Phase space distribution of electrons are taken into account by various algorithms. Generating functions and linear transfer matrices for particle tracking purposes can be calculated. Subroutines to calculate the effects of insertion devices on the storage ring are included. The program runs in batch mode, controlled by input files, but a simple GUI is also provided. The results are given as ASCII data or binary formats of the programs PAW, ROOT, and HDF5. Parallel runs of WAVE on a cluster are supported. WAVE has been checked and validated with the synchrotron radiation code of the German National Bureau of Standards (PTB) based on Schwinger's formula.

Slides TUACC2 [3.685 MB]

TUSCC3

Undulator Radiation Inside a Dielectric Waveguide

radiation, vacuum, insertion, synchrotron

96

A. Kotanjyan, A.A. Saharian
YSU, Yerevan, Armenia

We investigate the radiation from a charge moving along a helix around a dielectric cylinder immersed in a homogeneous medium. We are mainly concerned with the radiation propagating inside the cylinder. The radiation intensity for the modes propagating inside the cylinder is evaluated by the work done by the radiation field on the charge and by evaluating the energy flux through the cross-section of the cylinder. The insertion of a dielectric waveguide provides an additional mechanism for tuning the characteristics of the undulator radiation by choosing the parameters of the waveguide. The radiated energy inside the cylinder is redistributed among the cylinder modes, the corresponding spectrum differs significantly from the homogeneous medium or free-space results. This change is of special interest in the low-frequency range where the distribution of the radiation energy among small number of modes leads to the enhancement of the spectral density for the radiation intensity. The radiation emitted on the waveguide modes propagates inside the cylinder and the waveguide serves as a natural collector for the radiation.

Slides TUSCC3 [0.809 MB]

FRSAC1

Hybrid Programming and Performance for Beam Propagation Modeling

simulation, wakefield, cavity

284

M. Min, A. Mametjanov
ANL, Argonne, USA
J. Fu
RPI, Troy, New York, USA

Funding: DOE ASCR (Advanced Scientific Computing Research) Program
We examined hybrid parallel infrastructures in order to ensure performance and scalability for beam propagation modeling as we move toward extreme-scale systems. Using an MPI programming interface for parallel algorithms, we expanded the capability of our existing electromagnetic solver to a hybrid (MPI/shared-memory) model that can potentially use the computer resources on future-generation computing architecture more efficiently. As a preliminary step, we discuss a hybrid MPI/OpenMP model and demonstrate performance and analysis on the leadership-class computing systems such as the IBM BG/P, BG/Q, and Cray XK6. Our hybrid MPI/OpenMP model achieves speedup when the computation amounts are large enough to compensate the OMP threading overhead.

Slides FRSAC1 [4.252 MB]