| Paper | Title | Page |
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| WEP022 | Status of Low Emittance Tuning at CesrTA | 1540 |
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Funding: Work supported by the National Science Foundation and by the US Department of Energy under contract numbers PHY-0734867 and DE-FC02-08ER41538. We report on the status of emittance tuning techniques at the CESR Test Accelerator CesrTA. The CesrTA experimental program requires the capability to operate in a variety of machine lattices with the smallest possible emittance. We have attempted to minimize the turn-around time of our low emittance tuning procedure. We utilize high bandwidth BPM electronics for fast, precision measurements of orbit, betatron phase, transverse coupling, and dispersion. Turn by turn data is used to measure BPM button electrode gains to a under a percent. Gain-corrected coupling data is utilized to determine BPM tilts to 10mrad, allowing for measurement of vertical dispersion at the level of 10mm. Measurement and analysis of the data for characterizing BPM response takes 5 minutes. Beam based measurement of machine functions, data analysis, and implementing corrections in the machine takes another 5 minutes. An x-ray beam size monitor provides a real time check on the effectiveness of the procedure. A typical correction results in an emittance less than 20pm at 2.1GeV in 1-2 iterations. Sub 15pm has been achieved with adjustment of closed coupling/vertical dispersion bumps and betatron tunes. |
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