S R F    2 0 0 3

SRF2003 Show Abstract

Title Microphonics Measurements in RIA Cavities
Type Poster coupler / tuner / controls
Abstract Phase stabilization of the RIA drift-tube cavities in the presence of microphonics will drive the rf power requirements for the RIA driver linac.  Microphonics measurements on the ANL beta=0.4 two-cell spoke cavity have been performed many at high fields and using a new cavity resonance monitor devide developed in collaboration with JLAB. Cold tests on the fully jacketed two-cell spoke operated under realistic conditions are the first ever on a multi-cell spoke geometry and indicate exceptional performance in this regard with no low-lying mechanical modes which couple to the cavity rf eigenfrequency. Rather, at useful accelerating fields of Eacc=7-8 MV/m the modest frequency jitter (roughly 5 Hz RMS) is due to low frequency non-resonant vibrations from pool boiling in the helium bath. The issue of microphonics is being addressed at Argonne in three ways: (1) construction of piezoelectric and magnetostrictive tuners, (2) cavity design to reduce the pressure sensitivity and (3) reducing the source of helium pressure fluctuations.

List of authors...

Principle author first.

Last (Family) Name First Name (Initials only) Affiliation or Organization (abbreviations if possible)
Kelly M.P. ANL
Shepard K.W. ANL
Fuerst J.D. ANL
Kedzie M. ANL

SRF 2003Webmaster