Abstract
Off-axis beams passing through an accelerating cavity excite dipole modes among other higher order modes (HOMs). These modes have linear dependence on the transverse beam offset from the cavity axis. Therefore they can be used to monitor the beam position within the cavity. The fifth dipole pass band of the third harmonic superconducting cavities at FLASH has modes trapped within each cavity and do not propagate through the adjacent beam pipes, while most other cavity modes do. This could enable the beam position measurement in individual cavities. This paper investigates the possibility to use the fifth dipole band for beam alignment in the third harmonic cavity module. Simulations and measurements both with and without beam-excitations are presented. Various analysis methods are used and compared. A good correlation of HOM signals to the beam position is observed. Copyright © 2011 by IPAC'11/EPS-AG.
| Original language | English |
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| Title of host publication | IPAC 2011 - 2nd International Particle Accelerator Conference|IPAC - Int. Part. Accel. Conf. |
| Publisher | JACoW |
| Pages | 2891-2893 |
| Number of pages | 2 |
| ISBN (Print) | 9789290833666 |
| Publication status | Published - 2011 |
| Event | 2nd International Particle Accelerator Conference, IPAC 2011 - Kursaal, San Sebastian Duration: 1 Jul 2011 → … |
Conference
| Conference | 2nd International Particle Accelerator Conference, IPAC 2011 |
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| City | Kursaal, San Sebastian |
| Period | 1/07/11 → … |