Transient ponderomotive effects in superconducting cavities
A number of experiments were performed on an installed and operational 5-cell CEBAF cavity to determine the minimum time required to re-establish stable gradient after a cavity window arc trip. Once it was determined that gradient could be re-established within 10 ms by applying constant power RF signal in a voltage controlled Oscillator-phase locked loop based system (VCO-PLL), a second experiment was performed to determine if stable gradient could be re-established using a fixed frequency RF system with a simple gradient based closed loop control system. During this test, fluctuations were observed in the cavity forward power signal, the source of which was later determined to be pondero-motive in nature. These ponderomotive induced vibrations were quantified using a cavity resonance monitor and a VCO-PLL RF system. Experimental results, analysis of the resultant klystron power transients, the decay time of the transients, and the implications with respect to fast reset algorithms will be presented.
- Research Organization:
- TJNAF (Thomas Jefferson National Accelerator Facility, Newport News, VA)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-84ER40150
- OSTI ID:
- 859083
- Report Number(s):
- JLAB-ACE-05-439; DOE/ER/40150-3618
- Resource Relation:
- Conference: 12th SRF Workshop, Cornell University, July 10, 2005
- Country of Publication:
- United States
- Language:
- English
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