A 1-12 GeV/c Beam Transport for Transverse or Longitudinally Polarized Protons

A two-stage beam transport for polarized protons has been constructed and operated at the Argonne ZGS. The first stage delivers vertically polarized protons (N-type) to an elastic scattering polarimeter consisting of a 10 cm long LH2 target and two moveable sets of forward and recoil scintillation counters. The unscattered protons transported through the beam\´s second stage are focused onto the polarized proton target PPT-III; this target utilizes a 2.5 T "R and A" magnet to produce target polarizations in the horizontal plane, either in the beam direction (L-type) or transverse to it (S-type). The second stage of the beam is equipped with a combination of superconducting solenoids and dipole magnets; thus the beam polarization can also be rotated to point in the L or S direction. The entire system has been operated successfully over the momentum range 1.0 - 11.75 GeV/c with NS, LS, SS, and LL beam-target spin directions.