[SLAC] [SLAC Pubs and Reports]

New Apparatus for Precise Synchronous Phase Shift Measurements in Storage Rings


Measuring a synchronous phase shift as a function of beam current is commonly done in accelerator physics to estimate the longitudinal impedance of a storage ring vacuum chamber. This measurement is normally done with RF techniques that don't have enough accuracy to detect small phase shifts typical to the newer storage rings. In this paper we report results from a new method for precise measurement of a synchronous phase shift. Our method involves downmixing from the RF frequency to a kHz range and then using an audio DSP lock-in amplifier for the actual phase detection. This paper describes the idea and the advantages of a new method as well as its practical implementation in the apparatus we build for precise synchronous phase measurements in the Stanford Linear Collider damping rings. The results of those measurements are also presented.

Full Text


Compressed PostScript

More Information

Full bibliographic data for this document, including its complete author list, is (or soon will be) available from SLAC's SPIRES-HEP Database.

Please report problems with this file to posting@slac.stanford.edu. The SLAC preprint inventory is provided by the SLAC Technical Publications Department.
Page generated 04 Apr 2001 @ 15:08 PDT by htmlme.pl