RUPAC2012 - List of Authors (Bondarenko, T.V.)

Paper	Title	Page
TUPPB009	RF Self–Consistent Electron Beam Dynamics Simulation in THz Generator Based on Photoinjector and Cherenkov Decelerating System	328
	T.V. Bondarenko, S.M. Polozov, O.A. Tatsyuk MEPhI, Moscow, Russia
	The generator of high intensity monochromatic radiation in sub-mm band is currently under R&D at the Department of Electrophysical Facilities of MEPhI. This generator is based on photoinjector and irradiating Cherenkov capillary. It is necessary to have high brightness electron beams to generate of monochromatic radiation in this type of structure. These beams can be produced by photocathode and accelerated to energy of several MeV using short structure having high rate of energy gain. Irradiating capillary represents metal tube having inner radius of the radiation wavelength order and covered with dielectric layer or made of corrugated waveguide. It's important to study the self-consistent dynamics of the beam during the acceleration as the pulse current is equal several A, i.e. the beam dynamics should be studied taking into account RF (radiation) field and Coulomb field of self space charge. Another task is to study the electron beam dynamics and fields irradiated by it in decelerating structure in the absence of external fields. The scheme of the facility, its operation mode and high-current beam dynamics simulation results in accelerating and irradiating structures are presented.

TUPPB010	RF Quadrupole Focusing Lattices	331
	A.S. Plastun, T.V. Bondarenko MEPhI, Moscow, Russia
	Spatial homogeneity of a conventional RFQ allows to estimate parameters of the lattice easily. Hybrid-RFQ structures with spatially periodic RFQ lenses are more complicated in respect of beam dynamics. Transverse stability of beam motion is defined by lattice parameters. Basically parameters of RF focusing lattices are influenced by longitudinal emittance of a bunch in contrast to static focusing lattices. The paper presents a method which allows to evaluate parameters of a very wide class of RF and static quadrupole lattices. Transverse acceptance and acceleration rate could be determined. The method is useful to compare Hybrid-RFQ structures with a conventional RFQ.

WEPPC046	RF Photoinjector Parameters Optimization	535
	T.V. Bondarenko, S.M. Polozov MEPhI, Moscow, Russia
	Sources of high-power electromagnetic radiation in THz band are becoming promising as a new method of a low activation introscopy. Research and development of accelerating RF photoinjector for THz source are reported. The photoinjector is based on disk loaded waveguide (DLW). Photoinjector consists of two accelerating structures: widespread 1.6 cell DLW structure and travelling wave resonator structure based on 8 cells traveling wave accelerating structure. The resonant models of these structures and the structures with power ports were designed. Electrodynamics characteristics and electric field distribution for all models were acquired. Electrodynamics models were tuned to the resonant frequency of 3000 MHz. Magnetic field coupling between cells of accelerating structure and optimization of the diaphragms sizes were analyzed to enlarge the structures efficiency. Diaphragms windows profiles were optimized to decrease the overvoltage on the windows edges and to eliminate the breakdown possibility.

TUPPB040	Angiography X-ray Monochromatic Source Based on Radiation From Crystals	406
	T.V. Bondarenko, G.B. Sharkov Siemens LLC, Moscow, Russia Y.A. Bashmakov LPI, Moscow, Russia S.M. Polozov MEPhI, Moscow, Russia
	Nowadays angiography has become one of the most commonly used medical procedures. However the X-ray tubes are mostly used in angiography imaging systems. The problem that encounters in using X-ray tubes is low monochromaticity due to bremsstrahlung while angiography imaging requires quasimonochromatic energy spectrum for better image quality and lower dose rate obtained by the patient. The use of the monocrystaline target at the medical electron LINAC can be one of the possible ways to obtain the monochromatic X-ray radiation. This type of X-ray generator will provide monochromatic radiation with photon energy dependent on the electron beam energy. The X-ray generation mechanism, possibilities of monocrystal usage as an X-ray source for angiography and requirements for beam parameters are discussed.

Paper

Title

Page

RF Self–Consistent Electron Beam Dynamics Simulation in THz Generator Based on Photoinjector and Cherenkov Decelerating System

328

T.V. Bondarenko, S.M. Polozov, O.A. Tatsyuk
MEPhI, Moscow, Russia

The generator of high intensity monochromatic radiation in sub-mm band is currently under R&D at the Department of Electrophysical Facilities of MEPhI. This generator is based on photoinjector and irradiating Cherenkov capillary. It is necessary to have high brightness electron beams to generate of monochromatic radiation in this type of structure. These beams can be produced by photocathode and accelerated to energy of several MeV using short structure having high rate of energy gain. Irradiating capillary represents metal tube having inner radius of the radiation wavelength order and covered with dielectric layer or made of corrugated waveguide. It's important to study the self-consistent dynamics of the beam during the acceleration as the pulse current is equal several A, i.e. the beam dynamics should be studied taking into account RF (radiation) field and Coulomb field of self space charge. Another task is to study the electron beam dynamics and fields irradiated by it in decelerating structure in the absence of external fields. The scheme of the facility, its operation mode and high-current beam dynamics simulation results in accelerating and irradiating structures are presented.

TUPPB010

RF Quadrupole Focusing Lattices

331

A.S. Plastun, T.V. Bondarenko
MEPhI, Moscow, Russia

Spatial homogeneity of a conventional RFQ allows to estimate parameters of the lattice easily. Hybrid-RFQ structures with spatially periodic RFQ lenses are more complicated in respect of beam dynamics. Transverse stability of beam motion is defined by lattice parameters. Basically parameters of RF focusing lattices are influenced by longitudinal emittance of a bunch in contrast to static focusing lattices. The paper presents a method which allows to evaluate parameters of a very wide class of RF and static quadrupole lattices. Transverse acceptance and acceleration rate could be determined. The method is useful to compare Hybrid-RFQ structures with a conventional RFQ.

WEPPC046

RF Photoinjector Parameters Optimization

535

T.V. Bondarenko, S.M. Polozov
MEPhI, Moscow, Russia

Sources of high-power electromagnetic radiation in THz band are becoming promising as a new method of a low activation introscopy. Research and development of accelerating RF photoinjector for THz source are reported. The photoinjector is based on disk loaded waveguide (DLW). Photoinjector consists of two accelerating structures: widespread 1.6 cell DLW structure and travelling wave resonator structure based on 8 cells traveling wave accelerating structure. The resonant models of these structures and the structures with power ports were designed. Electrodynamics characteristics and electric field distribution for all models were acquired. Electrodynamics models were tuned to the resonant frequency of 3000 MHz. Magnetic field coupling between cells of accelerating structure and optimization of the diaphragms sizes were analyzed to enlarge the structures efficiency. Diaphragms windows profiles were optimized to decrease the overvoltage on the windows edges and to eliminate the breakdown possibility.

TUPPB040

Angiography X-ray Monochromatic Source Based on Radiation From Crystals

406

T.V. Bondarenko, G.B. Sharkov
Siemens LLC, Moscow, Russia
Y.A. Bashmakov
LPI, Moscow, Russia
S.M. Polozov
MEPhI, Moscow, Russia

Nowadays angiography has become one of the most commonly used medical procedures. However the X-ray tubes are mostly used in angiography imaging systems. The problem that encounters in using X-ray tubes is low monochromaticity due to bremsstrahlung while angiography imaging requires quasimonochromatic energy spectrum for better image quality and lower dose rate obtained by the patient. The use of the monocrystaline target at the medical electron LINAC can be one of the possible ways to obtain the monochromatic X-ray radiation. This type of X-ray generator will provide monochromatic radiation with photon energy dependent on the electron beam energy. The X-ray generation mechanism, possibilities of monocrystal usage as an X-ray source for angiography and requirements for beam parameters are discussed.