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arXiv · 1309.1063

One 4-Twist Helix Snake to Maintain Polarization in 8-120 GeV Proton Rings

F. Antoulinakis·E. A. Ljungman·A. Tai·C. A. Aidala·E. D. Courant·A. D. Krisch·W. Lorenzon·P. D. Myers·R. S. Raymond·D. W. Sivers·M. A. Leonova·Y. S. Derbenev·V. S. Morozov·A. M. Kondratenko
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Abstract

Solenoid Siberian snakes have successfully maintained polarization in particle rings below 1 GeV, but never in multi-GeV rings because the Lorentz contraction of a solenoid's integral B dl would require impractically long high-field solenoids. High energy rings, such as Brookhaven's 255 GeV Relativistic Heavy Ion Collider (RHIC), use only odd multiples of pairs of transverse B-field Siberian snakes directly opposite each other. When it became impractical to use a pair of Siberian Snakes in Fermilab's 120 GeV Main Injector, we searched for a new type of single Siberian snake, which should overcome all depolarizing resonances in the 8.9 - 120 GeV range. We found that one snake made of one 4-twist helix and 2 short dipoles could maintain the polarization. This snake design might also be used at other rings, such as Japan's 30 GeV J-PARC, the 12 - 24 GeV NICA proton-deuteron collider at JINR-Dubna, and perhaps RHIC's injector, the 25 GeV AGS.

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F. Antoulinakis, E. A. Ljungman, A. Tai, C. A. Aidala, E. D. Courant, A. D. Krisch, W. Lorenzon, P. D. Myers, R. S. Raymond, D. W. Sivers, M. A. Leonova, Y. S. Derbenev, V. S. Morozov, A. M. Kondratenko. 2013-09-04. One 4-Twist Helix Snake to Maintain Polarization in 8-120 GeV Proton Rings. https://doi.org/10.1103/physrevaccelbeams.20.091003

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