Speaker
Mr
Valeri Lebedev
(FNAL)
Description
If not suppressed the RF system noise can significantly affect the luminosity of
hadron collider. It causes the bunch lengthening with consecutive decrease of the
beam intensity. Presently, the RF noise is the second leading reason of bunch
lengthening in Tevatron yielding to the intrabeam scattering at the store
beginning. The noise is mainly created by microphonics in RF cavities and is
strongly suppressed by local feedback system. The report discusses the beam-based
and direct measurements of the RF noise in Tevatron. The beam measurements are
based on observing particle diffusion in satellite bunches to the center of the
distribution. Such choice allows one to reduce effects of the intrabeam scattering
and the beam-beam-effects. The measurements yielded the spectral density of RF
phase of about 4e-11 rad^2/Hz. The report also discusses the theory of bunch
lengthening required to compare the direct and beam-based measurements.
Author
Mr
Valeri Lebedev
(FNAL)
