150-MeV Pulse Stretcher of Tohoku University

The present paper describes the Tohoku University 150 MeV pulse stretcher and the results of the test operation. The ring stores a pulsed electron beam from the electron linac and converts it into a continuous one. The test operation has proved that it works successfully. Broadening of the extracted beam in the vertical direction due to a coupling resonance was observed in the early operation. This problem was resolved by readjustment of the tune. And an extracted beam of 1 μA has been obtained with a duty factor of 80 %. The energy spread of the extracted beam was measured to be 0.2 %.