T. Sugimura

Slow beam extraction at KSR with combination of third order resonance and RFKO

A slow extraction system for 100 MeV electrons at KSR utilizing third order resonance and RFKO is designed using the same straight section for beam injection. The COD control system with use of a steering magnet together with correction coils in three dipole magnets enable coexistence of such injection and extraction channels.

KSR as a pulse stretcher

A pulse stretcher mode of the electron storage ring, KSR, is presented. Such a scheme as includes the extraction system in the same straight section as the injection line is adopted in order to enable coexistence of the stretcher mode with the insertion device. This scheme also has a merit that it can use the same beam dump as the output beam from the electron linac.

A Pulse Stretcher by Slow Extraction Utilizing the Third-Order Resonance with the RF Knockout Method

A pulse stretcher operation of KSR using slow electron beam extraction by the third-order resonance in combination with an RF knockout method has been accomplished. The extracted beam energy, number of extracted electrons in a single pulse, maximum duration and duty factor are 60 MeV, 1.4×108, 40 s and 90%, respectively. The beam spill can be controlled from 0.2 s to 40 s by adjusting of the power for RF knockout.

Slow extraction of electron beam with combination of the third order resonance and RFKO

The stretcher mode of KSR has been experimentally tested. Up to now, a beam spill longer than 8 seconds has been attained by reducing RF knockout power. Improvement of extraction efficiency will be realized by ramping of betatron tune and formation of closed-orbit-distortion without the effect of non-linear sextupole magnets to make an aperture minimum at the first septum for extraction.

First beam circulation test of an electron storage/stretcher ring, KSR

In Kyoto University, we are constructing a compact electron storage/stretcher ring (KSR). The circumference is 25.7 m and the maximum beam energy is 300 MeV. The electron beam is injected from a 100 MeV linac through the doubly achromatic transport line. The beam test of the injection line was finished and the beam size and the dispersion were measured. The results are consistent with the design calculation. The beam current is 100 mA and the energy spread is +/-0.5% (FWHM). KSR uses the 1-turn injection scheme. The bump orbit is created by the perturbation magnet for the injection. The test of the bump magnet was carried out.

Present status of the electron linac as the injector for KSR

At Kyoto University, a 300 MeV electron storage ring, KSR, has been constructed for the research of the synchrotron radiation light. As an injector of the ring, an S-band electron linac with the energy of 100 MeV was constructed in October, 1995, and have been operated since then. We measured the transverse emittance of the 100 MeV electron beam using a profile monitor made of a fluorescent screen and quadrupole lenses. The horizontal and vertical ones are 0.44 /spl pi/.mm.mrad and 1.3 /spl pi/.mm.mrad, respectively. The beam from the linac is being used for the experiment of the parametric X-ray radiation from the silicon crystal at rather low duty factor.