| Paper | Title | Page |
|---|---|---|
| TUPMA099 | Adiabatic Damping of the Bunch-length in the Induction Synchrotron | 244 |
|
||
|
A fact that a bunch-length shrinks with the barrier-bucket acceleration in the induction synchrotron [1], where a single proton-bunch injected from the 500 MeV Booster was accelerated to 6 GeV in the KEK-PS, has been observed [2]. This has been supposed to be simply explained by a term of adiabatic damping. A technique to analytically deal with such an adiabatic dumping in a case of RF bucket acceleration is well-known; a WKB solution is employed for the small amplitude synchrotron oscillation. However, the simple WKB approach is not available for the present barrier-bucket acceleration, because the longitudinal motion always depends on the oscillation amplitude. A novel technique capable of quantitatively predicting the adiabatic phenomenon in the barrier-bucket acceleration has been newly developed. It turns out that the experimental result, numerical simulation, and analytic prediction have been in good agreement with each other. Theoretical approaches tell us that a bunch-length in the barrier-bucket acceleration never continues to shrink but achieves a constant value corresponding to the time duration between barrier voltages.
[1] K. Takayama and J. Kishiro, Nucl. Inst. Meth. A451/1, 304-317 (2000)[2] K. Takayama et al., “Experimental Demonstration of the Induction Synchrotron”, published soon. |