The K-V beam through an axisymmetric uniform-focusing channel is studied using the particle-core model. The beam halo-chaos is found, and a sample function controller is proposed based on mechanism of halo formation a...The K-V beam through an axisymmetric uniform-focusing channel is studied using the particle-core model. The beam halo-chaos is found, and a sample function controller is proposed based on mechanism of halo formation and strategy of controlling halo-chaos. We perform multiparticle simulation to control the halo by using the sample function controller. The numerical results show that our control method is effective. We also find that the radial ion density changes when the ion beam is in the channel： not only can the halo-chaos and its regeneration be eliminated by using the sample function control method, but also the density uniformity can be found at the beam＇s centre as long as an appropriate control method is chosen.展开更多
A backstepping control method is proposed for controlling beam halo-chaos in the periodic focusing channels （PFCs） of high-current ion accelerator. The analysis and numerical results show that the method, via adjust...A backstepping control method is proposed for controlling beam halo-chaos in the periodic focusing channels （PFCs） of high-current ion accelerator. The analysis and numerical results show that the method, via adjusting an exterior magnetic field, is effective to control beam halo chaos with five types of initial distribution ion beams, all statistical quantities of the beam halo-chaos are largely reduced, and the uniformity of ion beam is improved. This control method has an important value of application, for the exterior magnetic field can be easily adjusted in the periodical magnetic focusing channels in experiment.展开更多
This paper studies the Kapchinsky-Vladimirsky （K-V） beam through a triangle periodic-focusing magnetic field by using the particle-core model. The beam halo-chaos is found, and an idea of Gauss function controller i...This paper studies the Kapchinsky-Vladimirsky （K-V） beam through a triangle periodic-focusing magnetic field by using the particle-core model. The beam halo-chaos is found, and an idea of Gauss function controller is proposed based on the strategy of controlling the halo-chaos. It performs multiparticle simulation to control the halo by using the Gauss function control method. The numerical results show that the halo-chaos and its regeneration can be eliminated effectively, and that the radial particle density is uniform at the centre of the beam as long as the control method and appropriate parameter are chosen.展开更多
The K-V beam through a hackle periodic-focusing magnetic field is studied using the particle-core model. The beam halo-chaos is found, and a power function controller is proposed based on mechanism of halo formation a...The K-V beam through a hackle periodic-focusing magnetic field is studied using the particle-core model. The beam halo-chaos is found, and a power function controller is proposed based on mechanism of halo formation and strategy of controlling halo-chaos. Multiparticle simulation was performed to control the halo by using the power function control method. The results show that the halo-chaos and its regeneration can be eliminated effectively. We also find that the radial particle density evolvement is of uniformity at the beam’s centre as long as appropriate parameters are chosen.展开更多
The beam halo is a major issue for interaction region （IR） backgrounds at many colliders, for example, future linear colliders, B factories, and also it is an important problem at ATF2. In this paper, we report on t...The beam halo is a major issue for interaction region （IR） backgrounds at many colliders, for example, future linear colliders, B factories, and also it is an important problem at ATF2. In this paper, we report on the halo propagation along the ATF2 beam line with realistic apertures, the nonlinear optics influence on the increasing number of halo particles input is analyzed, and the transmitted halo particles distribution just before the last BPM is then described, the results from which will benefit the Compton recoil electrons measurement.展开更多
In order to study the backgrounds in the ATF2 beam line and the interaction point（IP）, this paper has developed an analytical method to give an estimation of the ATF beam halo distribution based on K. Hirata and K. ...In order to study the backgrounds in the ATF2 beam line and the interaction point（IP）, this paper has developed an analytical method to give an estimation of the ATF beam halo distribution based on K. Hirata and K. Yokoya＇s theory. The equilibrium particle distribution of the beam tail in the ATF damping ring is presented,with each electron affected by several stochastic processes such as beam-gas scattering, beam-gas bremsstrahlung and intra-beam scattering, in addition to the synchrotron radiation damping effects. This is a general method which can also be applied to other electron rings.展开更多
基金Project supported by the National Natural Science Foundation of China （Grant Nos 10247005 and 70071047） and the Scientific Research Foundation of China University of Mining and Technology for the Young （Grant No 2005A037）.
文摘The K-V beam through an axisymmetric uniform-focusing channel is studied using the particle-core model. The beam halo-chaos is found, and a sample function controller is proposed based on mechanism of halo formation and strategy of controlling halo-chaos. We perform multiparticle simulation to control the halo by using the sample function controller. The numerical results show that our control method is effective. We also find that the radial ion density changes when the ion beam is in the channel： not only can the halo-chaos and its regeneration be eliminated by using the sample function control method, but also the density uniformity can be found at the beam＇s centre as long as an appropriate control method is chosen.
基金Project supported by the Natural Science Foundation of Guangxi Province,China (Grant No 0640033)
文摘A backstepping control method is proposed for controlling beam halo-chaos in the periodic focusing channels （PFCs） of high-current ion accelerator. The analysis and numerical results show that the method, via adjusting an exterior magnetic field, is effective to control beam halo chaos with five types of initial distribution ion beams, all statistical quantities of the beam halo-chaos are largely reduced, and the uniformity of ion beam is improved. This control method has an important value of application, for the exterior magnetic field can be easily adjusted in the periodical magnetic focusing channels in experiment.
基金supported by the National Natural Science Foundation of China (Grant No 10247005)the Natural Science Foundation of the Anhui Higher Education Institutions of China (Grant No KJ2007B187)the Scientific Research Foundation of China University of Mining and Technology for the Young (Grant No OK060119)
文摘This paper studies the Kapchinsky-Vladimirsky （K-V） beam through a triangle periodic-focusing magnetic field by using the particle-core model. The beam halo-chaos is found, and an idea of Gauss function controller is proposed based on the strategy of controlling the halo-chaos. It performs multiparticle simulation to control the halo by using the Gauss function control method. The numerical results show that the halo-chaos and its regeneration can be eliminated effectively, and that the radial particle density is uniform at the centre of the beam as long as the control method and appropriate parameter are chosen.
基金Supported by the National Natural Science Foundation of China (Grant No. 10247005)the Natural Science Foundation of the Anhui Higher Education Bureau (Grant No. KJ2007B187)the Scientific Research Foundation of China University of Mining and Technology for the Young (Grant No. OK060119).
文摘The K-V beam through a hackle periodic-focusing magnetic field is studied using the particle-core model. The beam halo-chaos is found, and a power function controller is proposed based on mechanism of halo formation and strategy of controlling halo-chaos. Multiparticle simulation was performed to control the halo by using the power function control method. The results show that the halo-chaos and its regeneration can be eliminated effectively. We also find that the radial particle density evolvement is of uniformity at the beam’s centre as long as appropriate parameters are chosen.
基金Supported by National Natural Science Foundation of China (11175192)Agence Nationale de la Recherche of the French Ministry of Research (Programme Blanc, Project ATF2-IN2P3-KEK, contract, ANR-06-BLAN-0027)
文摘The beam halo is a major issue for interaction region （IR） backgrounds at many colliders, for example, future linear colliders, B factories, and also it is an important problem at ATF2. In this paper, we report on the halo propagation along the ATF2 beam line with realistic apertures, the nonlinear optics influence on the increasing number of halo particles input is analyzed, and the transmitted halo particles distribution just before the last BPM is then described, the results from which will benefit the Compton recoil electrons measurement.
基金Supported by National Foundation of Natural Science(11175192)France China Particle Physics Laboratory(FCPPL)
文摘In order to study the backgrounds in the ATF2 beam line and the interaction point（IP）, this paper has developed an analytical method to give an estimation of the ATF beam halo distribution based on K. Hirata and K. Yokoya＇s theory. The equilibrium particle distribution of the beam tail in the ATF damping ring is presented,with each electron affected by several stochastic processes such as beam-gas scattering, beam-gas bremsstrahlung and intra-beam scattering, in addition to the synchrotron radiation damping effects. This is a general method which can also be applied to other electron rings.
基金the National Natural Science Foundation of China(10247005)the Natural Science Foundation of theAnhui Higher Education Institutions of China(KJ2007B187)the Scientific Research Foundation of China University ofMining and Technology for the Young(OK060119)
