| Paper | Title | Page |
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| MPPE045 | Accelerator Physics Issues at the 2.5 GeV PLS Storage Ring | 2854 |
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| Over the past decade, PLS has served the synchrotron light source with the 2.0 GeV to 2.5 GeV electron beam. Accelerator physics issues at the present 2.5 GeV storage ring have been investigated in order to improve the performance of the light source. We present the issues of the low-beta lattice, low-emittance lattice, effects of six insertion devices on the lattice and low-alpha lattice, and show their effects on the beam dynamics in the storage ring. | ||
| MPPP027 | Suppression of the Longitudinal Coupled-Bunch Instabilities by the RF Phase Modulation in the Pohang Light Source | 1970 |
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| In the 2.5 GeV Pohang Light Source, we have investigated the suppression of the longitudinal coupled instabilities (CBI) caused by higher order modes (HOMs) of RF cavities. At higher beam current than 170 mA the 758 MHz or 1300 MHz HOMs occurred and the beam could be unstable. The longitudinal CBI could be suppressed by modulating the phase of an RF accelerating voltage at a frequency of 2 times the synchrotron oscillation frequency and by adjusting the water temperatures of the RF cavities. The longitudinal beam oscillations measured by streak camera in synchro-scan mode were shown. The experiment results were compared with the macro particle tracking simulation. | ||
| TPAT011 | Impedance Analysis of Longitudinal Bunch Shape Measurements at PLS | |
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| We measured the longitudinal bunch shape by streak camera at 2.5 GeV Pohang Light Source. The impedances estimated by a series R+L model indicate a resistance R= 960 ohm, an inductance L= 80 nH and a longitudinal impedance Z/n= 0.53 ohm. The scaling law for the bunch lengthenig is expressed as I0.22. The effects of insertion device in the ring on the ring impedance, particularly the vertical height of in-vacuum undulator are also presented. | ||
| ROPB005 | Recent Experiment Results on Fast Ion Instability at 2.5 GeV PLS | 466 |
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| We present recent experiment results on the fast ion instability that were performed at the PLS storage ring. With higher vacuum pressures of three orders of magnitude than nominal one by He gas injection into the ring, increases of a factor of around three in the vertical beam size were observed by interferometer system. From the various measurement results, we estimated growth times for the instability as a funcion of vacuum pressure and beam current. We also compared the results with those of the computer simulations and analytical calculations. | ||
| RPPT016 | Effects of Wakefields on the Microbunching Instabilities at PAL-XFEL | 1473 |
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| We present effects of the wakefields in accelerating structures of the S-band linac on the microbunching instabilties at the PAL-XFELs. Analytical calculations are performed to investigate the gains of the instabilities in the accelerator system for the PAL-XFELs. | ||
| RPPP003 | Proposal of the Next Incarnation of Accelerator Test Facility at KEK for the International Linear Collider | 874 |
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| The realization of the International Linear Collider (ILC) will require the ability to create and reliably maintain nanometer size beams. The ATF damping ring is the unique facility where ILC emittancies are possible. In this paper we present and evaluate the proposal to create a final focus facility at the ATF which, using compact final focus optics and an ILC-like bunch train, would be capable of achieving 35nm beam size. Such a facility would enable the development of beam diagnostics and tuning methods, as well as the training of young accelerator physicists. |