First observation of simultaneous alpha buckets in a quasi-isochronous storage ring
We present the first experimental evidence confirming the theoretical predictions of alpha buckets in an electron storage ring. By controlling both the first- and second-order momentum compaction factors, we succeeded in storing electrons simultaneously in a pair of alpha buckets or in either bucket alone. The two electron bunches are separated in energy by slightly less than 1% and the energy is tunable over a narrow range. The energy difference was directly measured using synchrotron light from an undulator. Simultaneous two-color light beams from an undulator were generated. By changing the rf voltage, we were able to vary the normally fixed longitudinal bunch separation.
Murphy
JB
National Synchrotron Light Source, Building 725C, Brookhaven National Laboratory, Upton, New York 11973, USA.
Kramer
SL