Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lb“2pi c/omega c (with lb = bunch length, omega c = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the electron cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor ~;;3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined vertical density"stripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.
Cyclotron Resonances in Electron Cloud Dynamics
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lb“2pi c/omega c (with lb = bunch length, omega c = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the electron cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor ~;;3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined vertical density"stripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lb“2pi c/omega c (with lb = bunch length, omega c = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the electron cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor ~;;3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined vertical density"stripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.
Electron Cyclotron Resonances in Electron Cloud Dynamics
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We report a previously unknown resonance for electron cloud dynamics. The 2D simulation code"POSINST" was used to study the electron cloud buildup at different z positions in the International Linear Collider positron damping ring wiggler. An electron equilibrium density enhancement of up to a factor of 3 was found at magnetic field values for which the bunch frequency is an integral multiple of the electron cyclotron frequency. At low magnetic fields the effects of the resonance are prominent, but when B exceeds ~;;(2 pi mec/(elb)), with lb = bunch length, effects of the resonance disappear. Thus short bunches and low B fields are required for observing the effect. The reason for the B field dependence, an explanation of the dynamics, and the results of the 2D simulations and of a single-particle tracking code used to elucidate details of the dynamics are discussed.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We report a previously unknown resonance for electron cloud dynamics. The 2D simulation code"POSINST" was used to study the electron cloud buildup at different z positions in the International Linear Collider positron damping ring wiggler. An electron equilibrium density enhancement of up to a factor of 3 was found at magnetic field values for which the bunch frequency is an integral multiple of the electron cyclotron frequency. At low magnetic fields the effects of the resonance are prominent, but when B exceeds ~;;(2 pi mec/(elb)), with lb = bunch length, effects of the resonance disappear. Thus short bunches and low B fields are required for observing the effect. The reason for the B field dependence, an explanation of the dynamics, and the results of the 2D simulations and of a single-particle tracking code used to elucidate details of the dynamics are discussed.
Electron Cloud Cyclotron Resonances in the Presence of a Short-bunch-length Relativistic Beam
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 43
Book Description
Computer simulations using the 2D code"POSINST" were used to study the formation of the electron cloud in the wiggler section of the positron damping ring of the International Linear Collider. In order to simulate an x-y slice of the wiggler (i.e., a slice perpendicular to the beam velocity), each simulation assumed a constant vertical magnetic field. At values of the magnetic field where the cyclotron frequency was an integral multiple of the bunch frequency, and where the field strength was less than approximately 0.6 T, equilibrium average electron densities were up to three times the density found at other neighboring field values. Effects of this resonance between the bunch and cyclotron frequency are expected to be non-negligible when the beam bunch length is much less than the product of the electron cyclotron period and the beam velocity, for a beam moving at v~;;c. Details of the dynamics of the resonance are described.
Publisher:
ISBN:
Category :
Languages : en
Pages : 43
Book Description
Computer simulations using the 2D code"POSINST" were used to study the formation of the electron cloud in the wiggler section of the positron damping ring of the International Linear Collider. In order to simulate an x-y slice of the wiggler (i.e., a slice perpendicular to the beam velocity), each simulation assumed a constant vertical magnetic field. At values of the magnetic field where the cyclotron frequency was an integral multiple of the bunch frequency, and where the field strength was less than approximately 0.6 T, equilibrium average electron densities were up to three times the density found at other neighboring field values. Effects of this resonance between the bunch and cyclotron frequency are expected to be non-negligible when the beam bunch length is much less than the product of the electron cyclotron period and the beam velocity, for a beam moving at v~;;c. Details of the dynamics of the resonance are described.
Electron Cyclotron Resonance Ion Sources and ECR Plasmas
Author: R Geller
Publisher: Routledge
ISBN: 1351453238
Category : Science
Languages : en
Pages : 449
Book Description
Acknowledged as the "founding father" of and world renowned expert on electron cyclotron resonance sources Richard Geller has produced a unique book devoted to the physics and technicalities of electron cyclotron resonance sources. Electron Cyclotron Resonance Ion Sources and ECR Plasmas provides a primer on electron cyclotron phenomena in ion sour
Publisher: Routledge
ISBN: 1351453238
Category : Science
Languages : en
Pages : 449
Book Description
Acknowledged as the "founding father" of and world renowned expert on electron cyclotron resonance sources Richard Geller has produced a unique book devoted to the physics and technicalities of electron cyclotron resonance sources. Electron Cyclotron Resonance Ion Sources and ECR Plasmas provides a primer on electron cyclotron phenomena in ion sour
Electron Cyclotron Emission And Electron Cyclotron Resonance Heating (Ec-15) - Proceedings Of The 15th Joint Workshop (With Cd-rom)
Author: John Lohr
Publisher: World Scientific
ISBN: 9814470996
Category : Science
Languages : en
Pages : 583
Book Description
These proceedings present the latest results in electron cyclotron emission, heating and current drive, with an emphasis on the physics and technology of Electron Cyclotron Emission, Electron Cyclotron Heating and Electron Cyclotron Current Drive applied to magnetic fusion research. The field is a key element in the development of fusion power and the ITER project now under construction.
Publisher: World Scientific
ISBN: 9814470996
Category : Science
Languages : en
Pages : 583
Book Description
These proceedings present the latest results in electron cyclotron emission, heating and current drive, with an emphasis on the physics and technology of Electron Cyclotron Emission, Electron Cyclotron Heating and Electron Cyclotron Current Drive applied to magnetic fusion research. The field is a key element in the development of fusion power and the ITER project now under construction.
Proceedings of the Fifteenth Joint Workshop on Electron Cyclotron Emission and Electron Cyclotron Resonance Heating
Author: John Lohr
Publisher: World Scientific
ISBN: 9812814647
Category : Science
Languages : en
Pages : 583
Book Description
These proceedings present the latest results in electron cyclotron emission, heating and current drive, with an emphasis on the physics and technology of Electron Cyclotron Emission, Electron Cyclotron Heating and Electron Cyclotron Current Drive applied to magnetic fusion research. The field is a key element in the development of fusion power and the ITER project now under construction.
Publisher: World Scientific
ISBN: 9812814647
Category : Science
Languages : en
Pages : 583
Book Description
These proceedings present the latest results in electron cyclotron emission, heating and current drive, with an emphasis on the physics and technology of Electron Cyclotron Emission, Electron Cyclotron Heating and Electron Cyclotron Current Drive applied to magnetic fusion research. The field is a key element in the development of fusion power and the ITER project now under construction.
Design Considerations for Cyclotron Resonance Oscillators
Author: Bernhard Kulke
Publisher:
ISBN:
Category : Cyclotron waves
Languages : en
Pages : 44
Book Description
Publisher:
ISBN:
Category : Cyclotron waves
Languages : en
Pages : 44
Book Description
Characterization of Electron Cyclotron Resonance Ion Source Instabilities by Charged Particle Diagnostics
Author: Bryan Isherwood
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 224
Book Description
Ion sources are invaluable tools for producing charge particles for scientific, industrial, and medical applications. In particular, Electron Cyclotron Resonance (ECR) ion sources (ECRIS) are high power sources capable of producing high intensity, high charge state beams of heavy ions. The system uses microwaves to resonantly heat of electrons within an inhomogeneous magnetic trap. However, the internal dynamics of the resulting plasma are complex and poorly understood. In particular, the excitation of kinetic instabilities within the plasma can make operating these ion sources difficult and unpredictable. This thesis focuses on studying these instabilities to determine ways to optimize ECRIS performance by minimizing their impact on the extracted beam current.This study focuses on two measurements that look at the steady-state and time-resolved measurements of charged particle currents escaping the ion source during stable and unstable operations. The first measurement is a novel diagnostic of electrons escaping confinement from the plasma chamber. The second was a measurement of high charge state ions (Ar8+) extracted from the plasma chamber over a broad set of parameter spaces. These measurements provide insight into the ideal operating conditions for an ECR ion source and the dynamics of the ion and electron populations within its plasma.
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 224
Book Description
Ion sources are invaluable tools for producing charge particles for scientific, industrial, and medical applications. In particular, Electron Cyclotron Resonance (ECR) ion sources (ECRIS) are high power sources capable of producing high intensity, high charge state beams of heavy ions. The system uses microwaves to resonantly heat of electrons within an inhomogeneous magnetic trap. However, the internal dynamics of the resulting plasma are complex and poorly understood. In particular, the excitation of kinetic instabilities within the plasma can make operating these ion sources difficult and unpredictable. This thesis focuses on studying these instabilities to determine ways to optimize ECRIS performance by minimizing their impact on the extracted beam current.This study focuses on two measurements that look at the steady-state and time-resolved measurements of charged particle currents escaping the ion source during stable and unstable operations. The first measurement is a novel diagnostic of electrons escaping confinement from the plasma chamber. The second was a measurement of high charge state ions (Ar8+) extracted from the plasma chamber over a broad set of parameter spaces. These measurements provide insight into the ideal operating conditions for an ECR ion source and the dynamics of the ion and electron populations within its plasma.
Dynamics of Ion-cyclotron Resonance Heating
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Studies of the Ion-cyclotron Resonance Instability
Author: Gordon K. Soper
Publisher:
ISBN:
Category : Cyclotrons
Languages : en
Pages : 146
Book Description
Publisher:
ISBN:
Category : Cyclotrons
Languages : en
Pages : 146
Book Description