| Paper | Title | Page |
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| MOZAKI01 | Compensation of the Crossing Angle with Crab Cavities at KEKB | 27 |
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The crab cavities are presently being installed in the KEKB rings to compensate the crossing angle at collision and thus increase luminosity. This will be the first experience with such cavities in colliders. Results on the beam operation of the new cavities, both for single and colliding beams, will be presented including the luminosity performance and limitations.
Work presented on behalf of the KEKB Accelerator Group. |
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| TUODAB01 | Variations of Betatron Tune Spectrum due to Electron Cloud Observed in KEKB | 825 |
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In order to investigate the characteristics of electron clouds, the wake effects were measured at KEKB using a test bunch placed behind a bunch-train, where there was a rapid decay in the electron cloud density. The current-dependent tune-shift of the test bunch exhibited nonlinear behaviour in the vertical plane [1]. By observing the tune spectrum, we found that the spectrum width expanded and this was accompanied with a large negative tune slope at a low cloud density and at a low bunch current. However, as the cloud density increased, the spectrum width shrunk and this was accompanied with a positive tune slope. These experimental results suggested that a high electron cloud density caused an anti-damping effect in the tune spectrum. We believe that the variations in the tune slope and spectrum width might be related to the wake field in the resonator model, where the wavelength is comparable to the bunch length.
[1] T. Ieiri et al., Proc. of EPAC06, Edinburgh, Scotland, 2101 (2006). |
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| TUPAN049 | Low Emittance Lattices and Final Focus Design for the SuperB Project | 1499 |
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For the SuperB project* very low emittances (horizontal < 1 nm) and small beta functions at the Interaction Points are required to achieve the design luminosity of 1036/cm2/s. Low emittance lattice have been designed, using the PEP-II magnets, for the two rings of 4 and 7 GeV, which will have the same emittances and damping times. A new Final Focus section has also been designed to get the strong focusing at the Interaction Point, at the same time providing local correction of the high chromaticity and exploiting the large crossing angle and crabbed waist concepts. Lattice features and chromaticity correction schemes will be discussed. Dynamic apertures, with damping wigglers similar to the ILC ones, will also be presented.
* P. Raimondi, "New Developments for SuperB Factories", Invited talk, this Conference |
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| TUPAN045 | Beam Operation with Crab Cavities at KEKB | 1487 |
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Beam operation with crab cavities is planned in early 2007 at KEKB. The crab crossing scheme is expected to increase the vertical beam-beam tune-shift parameter significantly. One crab cavity will be installed in each ring where conditions for beam optics are matched to compensate the beam crossing angle of 22 mrad. Operation results on collision tuning with the crab cavities will be presented.
For the KEKB Accelerator Group. |
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| THPAN042 | Recent Progress of Optics Correction at KEKB | 3321 |
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| In recently KEKB operation, we have to tune the operation parameters during about one week in order to recover the peak performance after the optics correction. This wrong reproducibility of the luminosity is a significant problem for the integrated luminosity of the physics run. In this paper, we present the progress of the optics correction to improve the reproducibility of the machine performance. |