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arXiv · 1301.7353

Momentum Cogging at the Fermilab Booster

K. Seiya·C. Drennan·W. A. Pellico·K. Triplett·A. Waller
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Abstract

The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2E17 protons/hour which is almost double the current operation at 1.1E17 protons/hour. The beam loss in the machine is going to be an issue. The booster accelerates beam from 400 MeV to 8GeV and extracts to The Main Injector (MI). Cogging is the process that synchronizes the extraction kicker gap to the MI by changing radial position of the beam during the cycle. The gap creation occurs at about 700MeV which is 6msec into the cycle. The variation of the revolution frequency from cycle to cycle is larger at lower energy and it is hard to control by changing the radial position because of aperture limitations. Momentum cogging is able to move the gap creation earlier by using dipole correctors and radial position feedback, and controlling the revolution frequency and radial position at the same time. The new cogging is going to save energy loss and aperture. The progress of the momentum cogging system development is going to be discussed in this paper.

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K. Seiya, C. Drennan, W. A. Pellico, K. Triplett, A. Waller. 2013-01-30. Momentum Cogging at the Fermilab Booster. https://arxiv.org/abs/1301.7353

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