| Paper |
Title |
Page |
| THPC024 |
Closed Orbit Correction at the LNLS UVX Storage Ring
|
3029 |
| |
- L. Liu, R. H.A. Farias, X. R. Resende, P. F. Tavares
LNLS, Campinas
|
|
| |
The orbit correction of stored electrons in the LNLS storage ring often needs a few iterations to converge to the smallest distortion. This is caused in part by the residual coupling between transverse planes. This coupling effect can be included in the correction algorithm leading to the best orbit in just one iteration. However, in the LNLS ring, the number of monitors equals the number of vertical correctors but surpasses the number of horizontal correctors. This means that the vertical orbit can be corrected to zero at the position monitors in the decoupled situation but the horizontal orbit cannot. For the coupled case, the incapacity of zeroing the horizontal orbit leaks into the vertical plane. This problem can be addressed by the eigenvector method with constraints.
|
|
| THPC032 |
Vertical Beam Size Reduction via Compensation of Residual Transverse Coupling
|
3047 |
| |
- T. F. Roque, X. R. Resende, P. F. Tavares
LNLS, Campinas
|
|
| |
The Brazilian Synchrotron Light Source (LNLS) is currently constructing a beamline which will make use of the radiation produced by the EPU installed in the storage ring (SR) in 2007. Various force tasks have been triggered by this new beamline in order to achieve required beam properties and stability. One of these tasks has to do with reducing the SR's vertical beam size at the straight section where the EPU is located, hence improving the radiation brilliance from the EPU. This report will describe our recent efforts in understanding and controlling what residual effects there are in the ring that dominate the ring's vertical beam size. In particular, we study the effects of residual coupling perturbations on the beam size through the transfer matrix formalism which, we argue, is the most appropriate. A beam model including transverse linear coupling is validated with measured closed orbit response functions. By Analyzing this model we are able to propose new skew quadrupole elements to the SR that might reduce the vertical beam size at the EPU section and we can infer the validity of results with a pinhole beam imaging system which we have available in our diagnostic beamline.
|
|