• K. Takeda, Y. Shoji
  LASTI, Hyogo

The emittance of a single-shot beam from the SPring-8 electron linac was measured. A stability of the linac beam was evaluated from the shot-by-shot fluctuation of the emittance. We used the electron storage ring NewSUBARU as a part of the measurement system. The electron beam from the linac was injected into the ring and circulated. The beam profile was measured by a fast-gated ICCD camera using the visible light in the ring. Because of the intentional dipole injection errors, the beam position oscillated after the injection in vertical and horizontal directions. It enabled a multi-record of turn-by-turn beam profiles in one camera frame. The profiles for several revolutions were used to reconstruct the emittance of the linac beam. The horizontal and the vertical betatron tunes were optimized for the emittance measurement because the beam storage was not necessary. We compared the results with that by Q-scanning at the beam transport line, which required multi-shot beam.