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تسجيل مستخدم جديدOne 4-Twist Helix Snake to Maintain Polarization in 8-120 GeV Proton Rings
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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 solenoids integral B dl would require impractically long high-field solenoids. High energy rings, such as Brookhavens 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 Fermilabs 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 Japans 30 GeV J-PARC, the 12 - 24 GeV NICA proton-deuteron collider at JINR-Dubna, and perhaps RHICs injector, the 25 GeV AGS.
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