Microwave Direct Phase Shift Measurements

N. Eddy, J. Crisp

Observed ‘AC-coupling’

The Data

• Over 50 events taken at MI60 – 12.5m with Dipoles– Each event records ~150 turns of data at

500MS/s– Record phase shift & beam from RWM– Data is processed offline

• Mixer Compensation Filter• 100 Turn Average

• Data was taken for 3 and 4 slip stacked batches with from 2-10 Booster turns

• Also have a few no beam events• Did not record a beam only (no drive) event

Summary

• Primary source of signal distortion was found to be due to Mixer low frequency attenuation– Compensated for with IIR filter

• Preliminary look at all data collected during Dec 16 study– No strong difference between 3 & 4 Batch– Non-linear dependence on bunch intensity

• Investigate Bunch Length dependence• Collect data in Dipole free straight section