Ashot Vardanyan - Academia.edu (original) (raw)

Papers by Ashot Vardanyan

arXiv (Cornell University), Nov 29, 2022

The development of the advanced Radio Frequency Timer of electrons is described. It is based on a... more The development of the advanced Radio Frequency Timer of electrons is described. It is based on a helical deflector, which performs circular or elliptical sweeps of keV electrons, by means of 500 MHz radio frequency field. By converting a time distribution of incident electrons to a hit position distribution on a circle or ellipse, this device achieves extremely precise timing. Streak Cameras, based on similar principles, routinely operate in the ps and sub-ps time domain, but have substantial slow readout system. Here, we report a device, where the position sensor, consisting of microchannel plates and a delay-line anode, produces ~ns duration pulses which can be processed by using regular fast electronics. A photon sensor based on this technique, the Radio Frequency Photo-Multiplier Tube (RFPMT), has demonstrated a timing resolution of ~10 ps and a time stability of ~0.5 ps, FWHM. This makes the apparatus highly suited for Time Correlated Single Photon Counting which is widely used in optical microscopy and tomography of biological samples. The first application in lifetime measurements of quantum states of graphene, under construction at the A. I. Alikhanyan National Science Laboratory (AANL), is outlined. This is followed by a description of potential RFPMT applications in time-correlated Diffuse Optical Tomography, time-correlated Stimulated Emission Depletion microscopy, hybrid FRET/STED nanoscopy and Time-of-Flight Positron Emission Tomography.

AREAL facility development implies energy upgrade to 50 MeV in order to drive a THz free electron... more AREAL facility development implies energy upgrade to 50 MeV in order to drive a THz free electron laser. To reach this goal, the installation of two 1.6 m long S-Band travelling wave accelerating sections, with nominal accel-erating gradient of 15 MV/m, are foreseen. In this paper the design study of accelerating sections along with the matching performance of RF couplers are presented. The simulations are performed using the CST Microwave Studio. The first results of the accelerating structure proto-type fabrication are discussed.

Transverse emittance is one of the most important properties for high-brightness electron beams u... more Transverse emittance is one of the most important properties for high-brightness electron beams used for X-Ray free-electron lasers. The photo injector test facility at DESY in Zeuthen (PITZ) focuses on the development of high-brightness electron sources. The two main methods to measure the emittance are the quadrupole scan and the slit scan. Combining either of these methods with a transverse deflecting cavity allows the measurement of the slice emittance. At PITZ, space-charge effects at the low beam momentum of 24 MeV/c complicate in particular the quadrupole scan. This has to be considered in the emittance measurements. First slit-scan based slice emittance results will be shown next to studies on the beam transport for quadrupole scans.

Advanced Research Electron Accelerator Laboratory (AREAL) is a 20 MeV laser driven RF linear acce... more Advanced Research Electron Accelerator Laboratory (AREAL) is a 20 MeV laser driven RF linear accelerator which is being constructed in the CANDLE institute. The construction of phase-1 is finished and at present the machine commissioning is in progress. In phase-1 a photocathode RF gun provides a 5 MeV small emittance electron beam with the 100 pC bunch charge and variable electron bunch length from 0.5 to 8 ps. Two main operation modes are foreseen for this phase – single and multibunch regimes to satisfy experimental demands. We report the status of linac, first experience and nearest machine run schedule. The brief review of the facility, main parameters, performance and first results are presented. AREAL. PHASE 1 A 20 MeV AREAL electron linear accelerator with photocathode RF gun was proposed and designed at the CANDLE Synchrotron Research Institute [1]. It aims to provide a base for advanced experimental study in the field of accelerator technology and dynamics of ultrafast pro...

The low energy sub-picosecond duration electron bunches with extremely small beam emittance have ... more The low energy sub-picosecond duration electron bunches with extremely small beam emittance have wide applications in advanced research of new accelerator concepts, radiation physics, time-resolved pulse radiolysis and electron diffraction. The conceptual design and experimental program of the Advanced Research Electron Accelerator Laboratory (AREAL) at CANDLE based on photocathode RF gun are presented. The AREAL design implies single and multibunch operation modes with variable beam energy of 5-20 MeV and 10-100 pC bunch charge. The design is based on 3 GHz 1.6 cells RF gun followed by S-Band accelerating linac.

AREAL (Advanced Research Electron Accelerator Laboratory) is a laser driven photocathode RF gun b... more AREAL (Advanced Research Electron Accelerator Laboratory) is a laser driven photocathode RF gun based electron linear accelerator project aimed to produce ultrashort bunches with small emittance. As the first phase of the project an electron RF gun was accomplished, providing short electron pulses with 5 MeV energy, which are used for ultrafast irradiation experiments in life and materials sciences [1]. For such experiments an exact calculation of the absorbed dose and electron bunch peak current is one of important conditions. The presence of a dark current in electron gun affects the electron emission from photocathode, the exact absorbed dose calculation, and in general, harms the machine performance. One of the possibilities to avoid the presence of a dark current in the experimental area is to use the energy difference between “on-phase” electron beam and “spread over RF pulse” dark current. Based on the energy difference the influence of focusing solenoid strength on each puls...

The design and constructional features of the control system for 500 MHz and 3 GHz RF system of C... more The design and constructional features of the control system for 500 MHz and 3 GHz RF system of CANDLE linac are presented. The linac includes an electron gun that is modulated by 500 MHz generator to produce 1 ns electron bunches, 500 MHz and 3 GHz bunchers, pre-accelerating cavity and the main accelerating section at 3 GHz . An important feature of the presented control system is a high level synchronisation of amplitude-phase characteristics of the sub-systems that provide the required energy-space characteristics of the accelerated beam. This puts strict requirements on RF frequency, amplitude and phase stabilization. A digital feedback system has been adopted to provide flexibility in the control algorithms. The main feature is a 9 MHz sampling rate for the cavity signals and digital I/Q detection. The design was performed using the RF analyze tool, based on MATLAB SIMULINK, which allows the simulation and analyzes of the field regulation quality. The simulation results for CAN...

Advanced Research Electron Accelerator Laboratory (AREAL) is an electron accelerator project base... more Advanced Research Electron Accelerator Laboratory (AREAL) is an electron accelerator project based on photocathode RF gun. The first phase of the facility is a 5 MeV energy RF phototgun, which is currently under operation. The facility developments imply energy upgrade to 50 MeV with further delivery of the electron beam to the undulator sections for Free Electron Laser and coherent undulator radiation in MIR and THz frequency ranges, respectively. In this report the design study of AREAL 50 MeV facility main systems along with the beam dynamics and characteristics of expected radiation are presented.

Following the design specifications of the Advanced Research Electron Accelerator Laboratory (ARE... more Following the design specifications of the Advanced Research Electron Accelerator Laboratory (AREAL), a reliable distributed cooling system for the AREAL linear accelerator has been developed. The cooling system provides a high accuracy temperature control for the electron gun, klystron and the magnets. The main requirements and technical solutions for various accelerator components cooling units are presented, including the local and remote control.

The RF station has been designed and constructed for AREAL Linac [1]. The constructional features... more The RF station has been designed and constructed for AREAL Linac [1]. The constructional features and commissioning results of RF system are presented in the current article. The whole RF system is designed to work at 3 GHz frequency. The linac includes an electron gun for 0.5-8 ps electron bunch production with 1-10 Hz repetition rate. For linac RF control system a Libera LLRF [2] stabilization system is used. An important feature of the presented system is a high level synchronization of amplitude-phase characteristics, which provides the required accuracy for particle acceleration and bunch formation.

Advanced Research Electron Accelerator Laboratory (AREAL) based on photo cathode RF gun is being ... more Advanced Research Electron Accelerator Laboratory (AREAL) based on photo cathode RF gun is being constructed at CANDLE. In current stage the gun section is under commissioning (phase 1). This paper presents the main characteristics of gun section beam diagnostics and the architecture of AREAL control system. The diagnostic system includes the measurements of beam charge, transverse profile, energy, energy spread and emittance. The results of the facility first phase commissioning are summarized from the beam diagnostic and control point of view. INTRODUCTION The main goal of the AREAL linear accelerator [1] is generation of 5-20 MeV energy, small emittance and ultrashort duration electron bunches for advanced research in the fields of accelerator and beam physics. For several experimental setup purposes the linac will operate in single and multi-bunch modes. The main design parameters of the electron beam are given in Table 1. Table 1: Beam Parameters List Main Parameters Single bun...

Journal of Instrumentation, 2017

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2016

The new high frequency travelling wave with single TE01 slow mode is studied. The structure is co... more The new high frequency travelling wave with single TE01 slow mode is studied. The structure is composed of a metallic tube with an internally coated low conductive thin layer. It is shown that the impedance of the internally coated metallic tube (ICMT) has a narrow-band single resonance at a high frequency. The resonant frequency corresponds to synchronous TM01 mode excited by the relativistic charge. The dispersion properties of the fundamental and and high order modes of ICMT structure are analysed. Proof-of-principle experimental setup at AREAL facility is given. The potential of the new structure for the particle acceleration and generation of monochromatic radiation in THz region are discussed.

Journal of Modern Physics, 2016

The studies of the influence of pico-second (4 × 10 −13 sec.) pulse electron irradiation with ene... more The studies of the influence of pico-second (4 × 10 −13 sec.) pulse electron irradiation with energy of 3.5 MeV on the electrical-physical properties of silicon crystals (n-Si) are presented. It is shown that in spite of relatively low electron irradiation energy, induced radiation defects are of cluster type. The behavior of main carrier mobility depending on temperature and irradiation dose is analyzed and charge carriers' scattering mechanisms are clarified: on ionized impurities, on point radiation defects with transition into cluster formation. Dose dependencies of electrical conductivity and carrier mobility for samples of various specific resistivities are given.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2016

Advanced Research Electron Accelerator Laboratory (AREAL) is a 50 MeV electron linear accelerator... more Advanced Research Electron Accelerator Laboratory (AREAL) is a 50 MeV electron linear accelerator project with a laser driven RF gun being constructed at the CANDLE Synchrotron Research Institute. In addition to applications in life and materials sciences, the project aims as a test facility for advanced accelerator and radiation source concepts. In this paper, the AREAL RF photoinjector performance, the facility design considerations and its highlights in the fields of free electron laser, the study of new high frequency accelerating structures, the beam microbunching and wakefield acceleration concepts are presented.

Two-beam acceleration scheme with separated trajectories based on Cherenkov radiation in the bicy... more Two-beam acceleration scheme with separated trajectories based on Cherenkov radiation in the bicylindrical waveguide with canal cut in the dielectric medium with the thin quasiconducting layer along the both axes is considered. The case of periodical sequence of the bunches is considered when a single-mode regime is installed as the frequency of the repetition rate of the bunches. The field distribution in the waveguide is researched. It is shown that sufficiently high intensities of the field are generated in the waveguide being suitable for the two-beam acceleration mechanism.

In order to produce high brightness electron beams with sub-picosecond bunch duration, the creati... more In order to produce high brightness electron beams with sub-picosecond bunch duration, the creation of Advanced Research Electron Accelerator Laboratory (AREAL) at CANDLE based on photocathode RF gun is under consideration. For several experimental setup purposes the linac will operate in single and multibunch modes with final beam energy 5-20 MeV and the bunch charge 10 –100 pC. The study of beam phase space evolution along the linac is performed to optimize the beam main characteristics: emittance, bunch length and energy spread. The dependence of longitudinal and transverse distribution of electrons in photocathode region on RF cavity performances is analyzed.

In this report the design layout and simulation study of the pre-injector for CANDLE project are ... more In this report the design layout and simulation study of the pre-injector for CANDLE project are presented. The pre-injector design includes the thermionic gun and the bunch formation systems. The gun is the standard triode gun, modulated by 500 MHz amplifier, which matches the beam pulse structure to the booster and storage ring RF buckets. The downstream 500 MHz and 1 GHz sub-harmonic bunching cavities perform an additional sub-bunching of the beam which will be accelerated in the 100 MeV S-Band injector linac. The single and multi bunch modes of the pre-injector operation are considered. The simulations are performed using PARMELA and E-Gun codes.

Electron-Photon Interaction in Dense Media, 2002

ABSTRACT It is well understood by the scientific community that the development of the interdisci... more ABSTRACT It is well understood by the scientific community that the development of the interdisciplinary science in the nearest decade will be concern with the generation of the high spectral flux and brilliance photon beams in soft and hard X-ray regions. The most desired way to produce such a photon beams is the Third Generation Light Source based on the intermediate energy (2.5–3.5 GeV) electron storage ring equipped by the special devices undulators and wigglers to cover the photon energy range of 1–50 keV with the spectral flux of 1014–1016 ph/sec in 0.1% band pass (BP) and spectral brightness up to 1020 ph/(mm2 mrad2 sec 0.1%BP). The protein crystallography, molecular binding mechanism, study of the polymers and new materials, the chemical dynamics, drug design and medical application, bio-informatics and telecommunications, the development of the nano-technology etc — are not exhausting list of the scientific case to be studied by experimentalists using synchrotron radiation produced by such a dedicated storage ring.

Plasma Physics Reports, 2001

The results of the experimental investigations of the relativistic electron bunched-beam interact... more The results of the experimental investigations of the relativistic electron bunched-beam interaction with plasma are presented. Energy spectrum of the electron beam on the exit of the interaction chamber at energy 50 and 20 MeV was measured. Coherent interaction of the electron beam with ultra-high frequency (UHF) plasma is investigated and indicated that in coherent conditions the greate fields may be generated, that are driven to the sharply beam current dependence on the phase of the UHF wave. Discovered new coherent effect may be used for development of an accelerating module with high gradient. The effect may be amplified with the help of powerfid parametric resonance. It may be usefd for thermonuclear researches, where the plasma is heated up by a high current relativistic electron beam as well.

arXiv (Cornell University), Nov 29, 2022

The development of the advanced Radio Frequency Timer of electrons is described. It is based on a... more The development of the advanced Radio Frequency Timer of electrons is described. It is based on a helical deflector, which performs circular or elliptical sweeps of keV electrons, by means of 500 MHz radio frequency field. By converting a time distribution of incident electrons to a hit position distribution on a circle or ellipse, this device achieves extremely precise timing. Streak Cameras, based on similar principles, routinely operate in the ps and sub-ps time domain, but have substantial slow readout system. Here, we report a device, where the position sensor, consisting of microchannel plates and a delay-line anode, produces ~ns duration pulses which can be processed by using regular fast electronics. A photon sensor based on this technique, the Radio Frequency Photo-Multiplier Tube (RFPMT), has demonstrated a timing resolution of ~10 ps and a time stability of ~0.5 ps, FWHM. This makes the apparatus highly suited for Time Correlated Single Photon Counting which is widely used in optical microscopy and tomography of biological samples. The first application in lifetime measurements of quantum states of graphene, under construction at the A. I. Alikhanyan National Science Laboratory (AANL), is outlined. This is followed by a description of potential RFPMT applications in time-correlated Diffuse Optical Tomography, time-correlated Stimulated Emission Depletion microscopy, hybrid FRET/STED nanoscopy and Time-of-Flight Positron Emission Tomography.

AREAL facility development implies energy upgrade to 50 MeV in order to drive a THz free electron... more AREAL facility development implies energy upgrade to 50 MeV in order to drive a THz free electron laser. To reach this goal, the installation of two 1.6 m long S-Band travelling wave accelerating sections, with nominal accel-erating gradient of 15 MV/m, are foreseen. In this paper the design study of accelerating sections along with the matching performance of RF couplers are presented. The simulations are performed using the CST Microwave Studio. The first results of the accelerating structure proto-type fabrication are discussed.

Transverse emittance is one of the most important properties for high-brightness electron beams u... more Transverse emittance is one of the most important properties for high-brightness electron beams used for X-Ray free-electron lasers. The photo injector test facility at DESY in Zeuthen (PITZ) focuses on the development of high-brightness electron sources. The two main methods to measure the emittance are the quadrupole scan and the slit scan. Combining either of these methods with a transverse deflecting cavity allows the measurement of the slice emittance. At PITZ, space-charge effects at the low beam momentum of 24 MeV/c complicate in particular the quadrupole scan. This has to be considered in the emittance measurements. First slit-scan based slice emittance results will be shown next to studies on the beam transport for quadrupole scans.

Advanced Research Electron Accelerator Laboratory (AREAL) is a 20 MeV laser driven RF linear acce... more Advanced Research Electron Accelerator Laboratory (AREAL) is a 20 MeV laser driven RF linear accelerator which is being constructed in the CANDLE institute. The construction of phase-1 is finished and at present the machine commissioning is in progress. In phase-1 a photocathode RF gun provides a 5 MeV small emittance electron beam with the 100 pC bunch charge and variable electron bunch length from 0.5 to 8 ps. Two main operation modes are foreseen for this phase – single and multibunch regimes to satisfy experimental demands. We report the status of linac, first experience and nearest machine run schedule. The brief review of the facility, main parameters, performance and first results are presented. AREAL. PHASE 1 A 20 MeV AREAL electron linear accelerator with photocathode RF gun was proposed and designed at the CANDLE Synchrotron Research Institute [1]. It aims to provide a base for advanced experimental study in the field of accelerator technology and dynamics of ultrafast pro...

The low energy sub-picosecond duration electron bunches with extremely small beam emittance have ... more The low energy sub-picosecond duration electron bunches with extremely small beam emittance have wide applications in advanced research of new accelerator concepts, radiation physics, time-resolved pulse radiolysis and electron diffraction. The conceptual design and experimental program of the Advanced Research Electron Accelerator Laboratory (AREAL) at CANDLE based on photocathode RF gun are presented. The AREAL design implies single and multibunch operation modes with variable beam energy of 5-20 MeV and 10-100 pC bunch charge. The design is based on 3 GHz 1.6 cells RF gun followed by S-Band accelerating linac.

AREAL (Advanced Research Electron Accelerator Laboratory) is a laser driven photocathode RF gun b... more AREAL (Advanced Research Electron Accelerator Laboratory) is a laser driven photocathode RF gun based electron linear accelerator project aimed to produce ultrashort bunches with small emittance. As the first phase of the project an electron RF gun was accomplished, providing short electron pulses with 5 MeV energy, which are used for ultrafast irradiation experiments in life and materials sciences [1]. For such experiments an exact calculation of the absorbed dose and electron bunch peak current is one of important conditions. The presence of a dark current in electron gun affects the electron emission from photocathode, the exact absorbed dose calculation, and in general, harms the machine performance. One of the possibilities to avoid the presence of a dark current in the experimental area is to use the energy difference between “on-phase” electron beam and “spread over RF pulse” dark current. Based on the energy difference the influence of focusing solenoid strength on each puls...

The design and constructional features of the control system for 500 MHz and 3 GHz RF system of C... more The design and constructional features of the control system for 500 MHz and 3 GHz RF system of CANDLE linac are presented. The linac includes an electron gun that is modulated by 500 MHz generator to produce 1 ns electron bunches, 500 MHz and 3 GHz bunchers, pre-accelerating cavity and the main accelerating section at 3 GHz . An important feature of the presented control system is a high level synchronisation of amplitude-phase characteristics of the sub-systems that provide the required energy-space characteristics of the accelerated beam. This puts strict requirements on RF frequency, amplitude and phase stabilization. A digital feedback system has been adopted to provide flexibility in the control algorithms. The main feature is a 9 MHz sampling rate for the cavity signals and digital I/Q detection. The design was performed using the RF analyze tool, based on MATLAB SIMULINK, which allows the simulation and analyzes of the field regulation quality. The simulation results for CAN...

Advanced Research Electron Accelerator Laboratory (AREAL) is an electron accelerator project base... more Advanced Research Electron Accelerator Laboratory (AREAL) is an electron accelerator project based on photocathode RF gun. The first phase of the facility is a 5 MeV energy RF phototgun, which is currently under operation. The facility developments imply energy upgrade to 50 MeV with further delivery of the electron beam to the undulator sections for Free Electron Laser and coherent undulator radiation in MIR and THz frequency ranges, respectively. In this report the design study of AREAL 50 MeV facility main systems along with the beam dynamics and characteristics of expected radiation are presented.

Following the design specifications of the Advanced Research Electron Accelerator Laboratory (ARE... more Following the design specifications of the Advanced Research Electron Accelerator Laboratory (AREAL), a reliable distributed cooling system for the AREAL linear accelerator has been developed. The cooling system provides a high accuracy temperature control for the electron gun, klystron and the magnets. The main requirements and technical solutions for various accelerator components cooling units are presented, including the local and remote control.

The RF station has been designed and constructed for AREAL Linac [1]. The constructional features... more The RF station has been designed and constructed for AREAL Linac [1]. The constructional features and commissioning results of RF system are presented in the current article. The whole RF system is designed to work at 3 GHz frequency. The linac includes an electron gun for 0.5-8 ps electron bunch production with 1-10 Hz repetition rate. For linac RF control system a Libera LLRF [2] stabilization system is used. An important feature of the presented system is a high level synchronization of amplitude-phase characteristics, which provides the required accuracy for particle acceleration and bunch formation.

Advanced Research Electron Accelerator Laboratory (AREAL) based on photo cathode RF gun is being ... more Advanced Research Electron Accelerator Laboratory (AREAL) based on photo cathode RF gun is being constructed at CANDLE. In current stage the gun section is under commissioning (phase 1). This paper presents the main characteristics of gun section beam diagnostics and the architecture of AREAL control system. The diagnostic system includes the measurements of beam charge, transverse profile, energy, energy spread and emittance. The results of the facility first phase commissioning are summarized from the beam diagnostic and control point of view. INTRODUCTION The main goal of the AREAL linear accelerator [1] is generation of 5-20 MeV energy, small emittance and ultrashort duration electron bunches for advanced research in the fields of accelerator and beam physics. For several experimental setup purposes the linac will operate in single and multi-bunch modes. The main design parameters of the electron beam are given in Table 1. Table 1: Beam Parameters List Main Parameters Single bun...

Journal of Instrumentation, 2017

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2016

The new high frequency travelling wave with single TE01 slow mode is studied. The structure is co... more The new high frequency travelling wave with single TE01 slow mode is studied. The structure is composed of a metallic tube with an internally coated low conductive thin layer. It is shown that the impedance of the internally coated metallic tube (ICMT) has a narrow-band single resonance at a high frequency. The resonant frequency corresponds to synchronous TM01 mode excited by the relativistic charge. The dispersion properties of the fundamental and and high order modes of ICMT structure are analysed. Proof-of-principle experimental setup at AREAL facility is given. The potential of the new structure for the particle acceleration and generation of monochromatic radiation in THz region are discussed.

Journal of Modern Physics, 2016

The studies of the influence of pico-second (4 × 10 −13 sec.) pulse electron irradiation with ene... more The studies of the influence of pico-second (4 × 10 −13 sec.) pulse electron irradiation with energy of 3.5 MeV on the electrical-physical properties of silicon crystals (n-Si) are presented. It is shown that in spite of relatively low electron irradiation energy, induced radiation defects are of cluster type. The behavior of main carrier mobility depending on temperature and irradiation dose is analyzed and charge carriers' scattering mechanisms are clarified: on ionized impurities, on point radiation defects with transition into cluster formation. Dose dependencies of electrical conductivity and carrier mobility for samples of various specific resistivities are given.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2016

Advanced Research Electron Accelerator Laboratory (AREAL) is a 50 MeV electron linear accelerator... more Advanced Research Electron Accelerator Laboratory (AREAL) is a 50 MeV electron linear accelerator project with a laser driven RF gun being constructed at the CANDLE Synchrotron Research Institute. In addition to applications in life and materials sciences, the project aims as a test facility for advanced accelerator and radiation source concepts. In this paper, the AREAL RF photoinjector performance, the facility design considerations and its highlights in the fields of free electron laser, the study of new high frequency accelerating structures, the beam microbunching and wakefield acceleration concepts are presented.

Two-beam acceleration scheme with separated trajectories based on Cherenkov radiation in the bicy... more Two-beam acceleration scheme with separated trajectories based on Cherenkov radiation in the bicylindrical waveguide with canal cut in the dielectric medium with the thin quasiconducting layer along the both axes is considered. The case of periodical sequence of the bunches is considered when a single-mode regime is installed as the frequency of the repetition rate of the bunches. The field distribution in the waveguide is researched. It is shown that sufficiently high intensities of the field are generated in the waveguide being suitable for the two-beam acceleration mechanism.

In order to produce high brightness electron beams with sub-picosecond bunch duration, the creati... more In order to produce high brightness electron beams with sub-picosecond bunch duration, the creation of Advanced Research Electron Accelerator Laboratory (AREAL) at CANDLE based on photocathode RF gun is under consideration. For several experimental setup purposes the linac will operate in single and multibunch modes with final beam energy 5-20 MeV and the bunch charge 10 –100 pC. The study of beam phase space evolution along the linac is performed to optimize the beam main characteristics: emittance, bunch length and energy spread. The dependence of longitudinal and transverse distribution of electrons in photocathode region on RF cavity performances is analyzed.

In this report the design layout and simulation study of the pre-injector for CANDLE project are ... more In this report the design layout and simulation study of the pre-injector for CANDLE project are presented. The pre-injector design includes the thermionic gun and the bunch formation systems. The gun is the standard triode gun, modulated by 500 MHz amplifier, which matches the beam pulse structure to the booster and storage ring RF buckets. The downstream 500 MHz and 1 GHz sub-harmonic bunching cavities perform an additional sub-bunching of the beam which will be accelerated in the 100 MeV S-Band injector linac. The single and multi bunch modes of the pre-injector operation are considered. The simulations are performed using PARMELA and E-Gun codes.

Electron-Photon Interaction in Dense Media, 2002

ABSTRACT It is well understood by the scientific community that the development of the interdisci... more ABSTRACT It is well understood by the scientific community that the development of the interdisciplinary science in the nearest decade will be concern with the generation of the high spectral flux and brilliance photon beams in soft and hard X-ray regions. The most desired way to produce such a photon beams is the Third Generation Light Source based on the intermediate energy (2.5–3.5 GeV) electron storage ring equipped by the special devices undulators and wigglers to cover the photon energy range of 1–50 keV with the spectral flux of 1014–1016 ph/sec in 0.1% band pass (BP) and spectral brightness up to 1020 ph/(mm2 mrad2 sec 0.1%BP). The protein crystallography, molecular binding mechanism, study of the polymers and new materials, the chemical dynamics, drug design and medical application, bio-informatics and telecommunications, the development of the nano-technology etc — are not exhausting list of the scientific case to be studied by experimentalists using synchrotron radiation produced by such a dedicated storage ring.

Plasma Physics Reports, 2001

The results of the experimental investigations of the relativistic electron bunched-beam interact... more The results of the experimental investigations of the relativistic electron bunched-beam interaction with plasma are presented. Energy spectrum of the electron beam on the exit of the interaction chamber at energy 50 and 20 MeV was measured. Coherent interaction of the electron beam with ultra-high frequency (UHF) plasma is investigated and indicated that in coherent conditions the greate fields may be generated, that are driven to the sharply beam current dependence on the phase of the UHF wave. Discovered new coherent effect may be used for development of an accelerating module with high gradient. The effect may be amplified with the help of powerfid parametric resonance. It may be usefd for thermonuclear researches, where the plasma is heated up by a high current relativistic electron beam as well.