Toward polarized antiprotons: Machine development for spin-filtering   experiments
  The paper describes the commissioning of the experimental equipment and the machine studies required for the first spin-filtering experiment with protons at a beam kinetic energy of $49.3\,$MeV in COSY. The implementation of a low-$\beta$ insertion made it possible to achieve beam lifetimes of $\tau_{\rm{b}}=8000\,$s in the presence of a dense polarized hydrogen storage-cell target of areal density $d_{\rm t}=(5.5\pm 0.2)\times 10^{13}\,\mathrm{atoms/cm^{2}}$. The developed techniques can be directly applied to antiproton machines and allow for the determination of the spin-dependent $\bar{p}p$ cross sections via spin filtering. 
C. Weidemann, F. Rathmann, H.J. Stein, B. Lorentz, Z. Bagdasarian, L.   Barion, S. Barsov, U. Bechstedt, S. Bertelli, D. Chi...
physics.acc-ph nucl-ex