| Paper |
Title |
Page |
| TUPCH129 |
Conceptual Design of a 3rd Harmonic Cavity System for the LNLS Electron Storage Ring
|
1316 |
| |
- N.P. Abreu, O.R. Bagnato, R.H.A. Farias, M.J. Ferreira, C. Pardine, P.F. Tavares
LNLS, Campinas
|
|
| |
The installation of a second RF cavity in the UVX electron storage ring at the Brazilian Synchrotron Light Laboratory (LNLS) at the end of 2003 brought about longitudinal instabilities driven by one of the HOMs of the new cavity. Even though the operational difficulties related to these unstable modes were successfully overcome by means of a combination of cavity tuning (using temperature and plunger adjustments) with phase modulation of the RF fields at the second harmonic of the synchrotron frequency, a more appropriate technique to avoid those problems is the use of higher harmonic cavities, which have the important advantage of providing damping of the longitudinal modes without increasing the energy spread, i.e., without compromising the longitudinal emittance. In this work we present the design of a passive higher harmonic cavity system optimized for operation at the LNLS storage ring. The parameters for a set of cavities as well as the analysis of some of the effects that they may introduce in the beam dynamics are presented. An overview of the technical aspects related to the project, construction and installation of the cavities in the storage ring is also presented.
|
|
| WEPCH005 |
Advances in Beam Orbit Stability at the LNLS Electron Storage Ring
|
1924 |
| |
- L. Liu, R.H.A. Farias, M.J. Ferreira, S.R. Marques, F. Rodrigues, P.F. Tavares, R.P.C.C. Tenca
LNLS, Campinas
|
|
| |
We describe recent efforts made at the Brazilian Synchrotron Light Source (LNLS) to improve beam orbit stability. The main driving force is the high positional stability required by some specific experiments and particularly by a high resolution undulator beamline which is being built at LNLS. Recent steps taken to improve orbit stability include the development of x-ray BPMs to measure the vertical position of the x-ray beam, analysis of RF BPM movement due to thermal load induced by synchrotron radiation after injection, new algorithms to deal with BPM electronics or control board false readings and revision and modification of their installations. In addition a weighted least squares method was developed to account for global correction while simultaneously privileging some local source point position. These upgrades are part of an ongoing work to improve beam orbit stability at LNLS.
|
|