Observation of beam-size blowup due to half-integer resonance in a synchrotron

Abstract

Beam blowup due to a half-integer resonance was observed in the HIMAC synchrotron with a nondestructive two-dimensional beam-profile monitor. As the betatron tune approached a half-integer, the vertical beam size became larger by about 13%. The measured rms beam size is in good agreement with a space-charge-included numerical simulation.