  Understanding the transition-crossing process is crucial for improving
Booster performance at high intensity. The synchronous phase appears to drop
toward 90 degrees right after transition regardless of beam intensity, more so
at higher beam intensity. The implication is that the effective rf voltage
(RFSUM) will run into a limit right after transition when the synchronous phase
reaches 90 degrees for high intensity beam. A reduction in RFSUM is also
observed at the same time. Solutions, such as raising the rf voltage during the
transition period or controlling the RFSUM reduction by increasing longitudinal
emittance before transition, are potentially important for high intensity
operation.
