| Paper | Title | Page |
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| MOPCH088 | Ion Cooler Storage Ring, S-LSR | 237 |
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Ion cooler and storage ring, S-LSR has been constructed. Its beam commissioning has been successfully performed since October, 2005 and electron beam cooling for 7 MeV proton beam has been performed with both flat and hollow spatial distributions. Effect of relative velocity sweep between electron and ion beams on the cooling time* has been confirmed. Based on the success to create the peaks in the energy spectrum of laser-produced ions, injection of laser-produced ions into S-LSR after rotation in the longitudinal phase space by an RF cavity synchronized to the pulse laser is under planning in order to apply electron cooling for such real laser produced hot ions. Three dimensional laser cooling satisfying the condition of 'tapered cooling' is also under investigation. 24Mg+ ions are to be laser-cooled only in the 'Wien Filter' in order to be cooled down to the appropriate energy according to their horizontal positions**. In parallel with the computer simulation, construction of the laser cooling system with use of ring dye laser accompanied with the second harmonics generator is now underway.
*H. Fadil et al. Nucl. Instr. & Meth. in Phys. Res. A517, 1-8 (2004).**A. Noda and M. Grieser, Beam Science and Technology, 9, 12-15 (2005). |
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| TUPLS066 | Peculiarities of Electron Cooler Operation and Construction at Ultra Low Energy in an Electrostatic Ring | 1645 |
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| Few projects of electrostatic rings with electron cooler are discussed now. Electron cooling at low electron energy of 10 eV was realized at the KEK electrostatic ring. The electron cooling permits to suppress the ion multi scattering on residual gas atoms and allows increasing the ion lifetime. Peculiarities of an electron cooler operation and construction at ultra low energy in an electrostatic ring are considered. The cooler gun operation regime is cardinally changed at a reduction of the electron energy to a value comparable with a cathode work function. A virtual cathode and ohmic resistance of cathode emitter give an input in beam formation at ultra low energy. Effective electron cooling of heavy atomic and bimolecular ions at mass of 100-1000 is reached at a small photocathode diameter of 1 mm and a high magnetic expansion factor of 10-1000. The electron cooler construction has traditional design in KEK electrostatic ring. The cooler construction can be simplified at a small circumference of electrostatic ring. Straight cooler schemes without toroidal magnets permit to reduce ring space required for electron cooler. | ||
| WEPLS022 | ILC Beam Energy Measurement based on Synchrotron Radiation from a Magnetic Spectrometer | 2442 |
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| The magnetic spectrometer with a relative energy resolution of 5·10-5 was proposed for ILC beam energy measurements. The beam energy measurement is based on precise definition of the beam position at a resolution of 100 nm and B-field integral at an accuracy of 2E-5. A complementary method of the beam energy measurement is proposed at registration of synchrotron radiation (SR) from the energy spectrometer dipole magnets. The measurements of both edge horizontal positions for SR fan on a distance of 50-70 m downstream of the spectrometer magnets permit to determine the beam energy with required resolution. The main principles of the beam energy measurements based on SR, the numerical simulations of SR performed by the GEANT code and proposal of SR monitors with submicron resolution are discussed. | ||
| THPCH053 | Numerical and Experimental Study of Cooling-stacking Injection in HIMAC Synchrotron | 2907 |
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| The cooling-stacking injection at the HIMAC synchrotron was used to increase the intensity of Ar18+ ion beam. The beam stacking was realized in a horizontal free phase-space, which was created by the HIMAC electron cooler. The stack intensity of (1.5~2.5)·109 ppp was accumulated at an injection intensity of (0.3~1.0)e9. The stack intensity was limitted by the ion lifetime. A peculiarity of present cooling-stacking experiments is related to lifetime difference by a factor of 2~3 of the stack and injected ions. The lifetime of stack ions is determined by vacuum pressure. The new injected ions were slowly lost at multiple scattering on residual gas atoms at diffusion heating in the vertical direction caused by the acceptance of 30pi-mm-mrad and a reduction of cooling force at large betatron amplitudes. The results of numerical simulations and experimental study of cooling-stacking injection on the HIMAC synchrotron are presented. | ||
| TUPLS064 | Design and Commissioning of a Compact Electron Cooler for the S-LSR | 1639 |
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| The ion cooler ring S-LSR has been constructed and commissioned in October 2005. The ring successfully stored a 7 MeV proton beam. The S-LSR is equipped with a compact-electron cooler which has a cooling solenoid length of 0.8 m, a toroid bending radius of 0.25 m and maximum magnetic field in the cooling section of 0.5 kG. The commissioning of the electron cooler was carried out with successful observation of both longitudinal and horizontal cooling of the proton beam. By varying the electric potential on the Pierce electrode in the gun, we have investigated the possibility of generating a hollow shaped electron beam, and studied its effect on the electron cooling process. Also the effect of the electrostatic deflector, installed in the toroid section in order to compensate the drift motion of the secondary electrons, was investigated. The design and results of the commissioning of the compact electron cooler are presented. | ||
| TUPLS065 | Beam Commissioning of Ion Cooler Ring, S-LSR | 1642 |
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| S-LSR is a new ion cooler ring constructed in Kyoto University. The circumference is 22.557 m and the maximum magnetic rigidity is 1 Tm. The constructiion and the vacuum baking had been finished in September, 2005. The beam commissioning was started since October, 2005. The injected beam is 7 MeV proton from the existing linac. The beam circulation test and the electron beam cooling were carried out successfully and the beam information and the characteristics of the ring were measured. One of the subjects of S-LSR is a realization of the crystalline beams using the electron and laser cooling. The lattice of S-LSR was designed to suppress the beam heating as much as possible and we also present such measurement results in this paper. | ||
| TUPLS078 | Design Studies of the Compact Superconducting Cyclotron for Hadron Therapy | 1678 |
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| An overview of the current status of the design of the compact superconducting isochronous cyclotron C400 able to deliver ion beams with a charge to mass ratio of 0.5 is given. This cyclotron is based on the design of the current PT (proton therapy) C230 cyclotron and will be used for radiotherapy with proton, helium or carbon ions. 12C6+ and 4He2+ ions will be accelerated to 400 MeV/u energy and extracted by electrostatic deflector, H2+ ions will be accelerated to the energy 260MeV and extracted by stripping. Computer modeling results on the axial injection system, magnetic system, inflector and center design are given. Results of simulations of the ion beam injection, acceleration and extraction are presented. | ||
| THPLS133 | Simulations of Electromagnetic Undulator for Far Infrared Coherent Source of TTF at DESY | 3595 |
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| A perspective extension of the VUV FEL user facility at DESY is infrared coherent source on the base of electromagnetic undulator. The undulator consists of 9 periods, period length is 40 cm long, and peak magnetic field is up to 1.2 T. With the energy of electron beam of 500 MeV maximum radiation wavelength is about 200 mkm. An important feature of the beam formation system of the VUV FEL is the possibility to produce ultra-short, down to 50 mkm rms electron bunches. Such short bunches produce powerful coherent radiation with multi-megawatt power level. FIR coherent source operates in a parasitic mode utilizing electron beam passed VUV undulator. Generation of two-colors by a single electron bunch reveals unique possibility to perform pump-probe experiments with VUV and FIR radiation pulses. In this report we present simulations of the undulator magnetic system and beam dynamics. |