| Paper |
Title |
Page |
| MOPLT035 |
Beam Induced Heating of the SPS Fast Pulsed Magnets
|
623 |
| |
- J.A. Uythoven, G. Arduini, T. Bohl, F. Caspers, E.H.R. Gaxiola, T. Kroyer, M. Timmins, L. Vos
CERN, Geneva
|
|
| |
Fast pulsed magnets with ferrite yokes are used in CERN?s SPS accelerator for beam injection, extraction and excitation for tune measurements. The impedance of the ferrite structures can provoke significant beam induced heating, especially for beams with high peak currents as for LHC operation, even beyond the Curie temperature. The expected heating in the different kicker systems for various operational modes is compared with beam measurements. Estimates of the beam induced power have been derived from measured beam spectra. A fast extraction kicker system has recently been equipped with a cooling system. The measured cooling performance is compared with data from laboratory setups and numerical simulations.
|
|
| TUPLT008 |
A Retrofit Technique for Kicker Beam-coupling Impedance Reduction
|
1144 |
| |
- F. Caspers, E.H.R. Gaxiola, T. Kroyer, M. Timmins, J.A. Uythoven
CERN, Geneva
- S.S. Kurennoy
LANL/LANSCE, Los Alamos, New Mexico
|
|
| |
The reduction of the impedance of operational ferrite kicker structures may be desirable in order to avoid rebuilding such a device. Often resistively coated ceramic plates or tubes are installed for this purpose but at the expense of available aperture. Ceramic U-shaped profiles with a resistive coating fitting between the ellipse of the beam and the rectangular kicker aperture have been used to significantly reduce the impedance of the magnet, while having a limited effect on the available physical aperture Details of this method, constraints, measurements and simulation results as well as practical aspects are presented and discussed.
|
|
| THPLT014 |
Coupler Structures for the LHC Beam-pipe Waveguide Mode Reflectometer
|
2490 |
| |
- T. Kroyer
TU Vienna, Vienna
- F. Caspers
CERN, Geneva
|
|
| |
The LHC reflectometer will be used to detect and localize obstacles and other kinds of discontinuities in the LHC beam screen. An important part of this device is the RF coupler element, which provides the interface between the circular beam screen and the measurement equipment. Two different scenarios of operation are considered. The first option consists in carrying out measurements during assembly by directly branching a coupler to the end of the beam screen. The other one is a permanent installation to be used in situ requiring a different kind of coupler to keep the aperture free. The goal is to achieve a reasonably well-matched spurious mode-free excitation over a 25% bandwidth for the TM01 and the T·1011 mode, respectively. The fulfillment of the required features is severely complicated by space and material restrictions arising mainly from vacuum and installation constraints.
|
|