Paper | Title | Page |
---|
WEP62 | Diagnosis, analysis, and resolution of thermal stability issues with HOM couplers on prototype CEBAF SRF cavities | 656 |
| - C. E. Reece, E. F. Daly, G. K. Davis, W. R. Hicks, T. Rothgeb, H. L. Phillips, J. Preble, H. Wang, G. Wu
TJNAF
| |
| During initial testing of the prototype cavities
incorporated into the developmental cryomodule
Renascence severe thermal stability issues were
encountered during CW operation. Additional diagnostic
instrumentation was added. This enabled identification of
an unanticipated thermal impedance between the HOM
coupler probe feedthrough assembly and the cavity
beamtube. Subsequent detailed FE analysis successfully
modeled the situation and indicated the need for alternate
cooling path for the couplers on those cavities. HOM
damping was measured to be adequate employing only
two of the four HOM couplers. The two pickup probes on
the couplers at the input power coupler side of each cavity
were removed, the remaining HOM probe feedthroughs
were heat stationed to two-phase helium supply piping,
and a novel heat sink was added to station both the inner
and outer conductors of the remaining HOM rf cables.
The characterization measurements, analysis,
modifications, and resulting performance are presented. | |
WEP66 | High pressure rinsing system studies | 664 |
| - D. Sertore, M. Fusetti, P. Michelato, C. Pagani
INFN Milano-LASA - T. Higo, J. Hong, K. Saito
KEK - G. Ciovati, T. Rothgeb
JLab - A. Matheisen, N. Krupka
DESY
| |
| High pressure rinsing (HPR) is a key process for the
surface preparation of high field superconducting cavities.
HPR water jets used in different laboratories have been
characterized measuring the transferred momentum
between the water jet and a target connected to a load cell.
The information taken during these measurements,
combined with HPR process parameters, allow
calculating new significant measurable variables such as
the jet power, the deposited energy on the cavity surfaces
and the pressure. | |