| Paper | Title | Page |
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| MOP68 | Ribbon Ion Beam Dynamics in Undulator Linear Accelerator | 177 |
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The possibility to use radio frequency undulator fields for ion beam focusing and acceleration in linac (UNDULAC-RF) is discussed. In periodical resonator structure the accelerating force is produced by the combination of two or more space harmonics of a longitudinal or a transverse undulator field*. The particle motion equations in Hamilton form are carried out by means of smooth approximation. The analysis of 3D effective potential permits to find the conditions under which focusing and acceleration of the particles occur simultaneously. The analytical results are verified with a numerical simulation. Examples illustrating the efficiency of the proposed method of acceleration are given for longitudinal and transverse undulators. The results are compared with a conventional linac and the other possibility of ion beam acceleration in UNDULAC-E(M) where electrostatic and magnetic fields are used.
*E.S. Masunov, Technical Physics, Vol. 46, No.11, 2001, pp. 1433-1436. |
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| TUP26 | Alternating Phase Focusing in Low-Velocity Heavy-Ion Superconducting Linac | 348 |
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| The low-charge-state injector linac of the RIA post-accelerator is based on ~60 independently phased SC resonators providing total ~70 MV accelerating potential. The low charge-state beams, however, require stronger transverse focusing, particularly at low velocities, than is used in existing SC ion linacs. For the charge-to-mass ratios considered here (q/A = 1/66) the proper focusing can be reached by the help of strong SC solenoid lenses with the field up to 15 T. Magnetic field of the solenoids can be reduced to 9 T applying an Alternating Phase Focusing (APF). A method to set the rf field phases has been developed and studied both analytically and by the help of the three-dimensional ray tracing code. The paper discusses the results of these studies. | ||
| THP22 | 3D Beam Dynamics Simulation in Undulator Linac | 642 |
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The ion beam can be bunched and accelerated in linear accelerator with RF undulator (UNDULAC-RF). The acceleration and focusing of beam can be realized without using a synchronous wave*. In this paper the computer simulation of high intensity ion beam dynamics in UNDULAC-RF was carried out by means of the "superparticles" method. The computer simulation and optimization of ion dynamics consist of two steps. At the first, the equations of particles motion in polyharmonic fields are devised by means of smooth approximation. Hamiltonian analysis of these equations allows to find a velocity of reference particle in polyharmonic field and to formulate the conditions of good longitudinal bunching and transverse focusing beam. At the second, the 3D ion beam dynamics simulation in an UNDULAC is governed by founded functions of reference particle velocity and a ratio of amplitude harmonics. The influence of the space charge on RF focusing conditions, transmission coefficient, longitudinal and transverse emittances, and other acceleration system characteristics are investigated by computer simulation.
*Masunov E.S., Sov. Phys.-Tech. Phys., vol. 35, No. 8, p. 962, 1990. |