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arXiv · 1204.6002

Higher Order Spin Resonances in a 2.1 GeV/c Polarized Proton Beam

M. A. Leonova·J. A. Askari·K. N. Gordon·A. D. Krisch·J. Liu·V. S. Morozov·D. A. Nees·R. S. Raymond·D. W. Sivers·V. K. Wong·F. Hinterberger
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Abstract

Spin resonances can depolarize or spin-flip a polarized beam. We studied 1st and higher order spin resonances with stored 2.1 GeV/c vertically polarized protons. The 1st order vertical (νy) resonance caused almost full spin-flip, while some higher order νy resonances caused partial depolarization. The 1st order horizontal (νx) resonance caused almost full depolarization, while some higher order νx resonances again caused partial depolarization. Moreover, a 2nd order νx resonance is about as strong as some 3rd order νx resonances, while some 3rd order νy resonances are much stronger than a 2nd order νy resonance. One thought that νy spin resonances are far stronger than νx, and that lower order resonances are stronger than higher order; the data do not support this.

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M. A. Leonova, J. A. Askari, K. N. Gordon, A. D. Krisch, J. Liu, V. S. Morozov, D. A. Nees, R. S. Raymond, D. W. Sivers, V. K. Wong, F. Hinterberger. 2012-04-26. Higher Order Spin Resonances in a 2.1 GeV/c Polarized Proton Beam. https://doi.org/10.1103/physrevlett.108.074801

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