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arXiv · 1407.6724

Toward polarized antiprotons: Machine development for spin-filtering experiments

C. Weidemann·F. Rathmann·H. J. Stein·B. Lorentz·Z. Bagdasarian·L. Barion·S. Barsov·U. Bechstedt·S. Bertelli·D. Chiladze·G. Ciullo·M. Contalbrigo·S. Dymov·R. Engels·M. Gaisser·R. Gebel·P. Goslawski·K. Grigoriev·G. Guidoboni·A. Kacharava·V. Kamerdzhiev·A. Khoukaz·A. Kulikov·A. Lehrach·P. Lenisa·N. Lomidze·G. Macharashvili·R. Maier·S. Martin·D. Mchedlishvili·H. O. Meyer·S. Merzliakov·M. Mielke·M. Mikirtychiants·S. Mikirtychiants·A. Nass·N. N. Nikolaev·D. Oellers·M. Papenbrock·A. Pesce·D. Prasuhn·M. Retzlaff·R. Schleichert·D. Schröer·H. Seyfarth·H. Soltner·M. Statera·E. Steffens·H. Stockhorst·H. Ströher·M. Tabidze·G. Tagliente·P. Thörngren Engblom·S. Trusov·Yu. Valdau·A. Vasiliev·P. Wüstner
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Abstract

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.

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C. Weidemann, F. Rathmann, H. J. Stein, B. Lorentz, Z. Bagdasarian, L. Barion, S. Barsov, U. Bechstedt, S. Bertelli, D. Chiladze, G. Ciullo, M. Contalbrigo, S. Dymov, R. Engels, M. Gaisser, R. Gebel, P. Goslawski, K. Grigoriev, G. Guidoboni, A. Kacharava, V. Kamerdzhiev, A. Khoukaz, A. Kulikov, A. Lehrach, P. Lenisa, N. Lomidze, G. Macharashvili, R. Maier, S. Martin, D. Mchedlishvili, H. O. Meyer, S. Merzliakov, M. Mielke, M. Mikirtychiants, S. Mikirtychiants, A. Nass, N. N. Nikolaev, D. Oellers, M. Papenbrock, A. Pesce, D. Prasuhn, M. Retzlaff, R. Schleichert, D. Schröer, H. Seyfarth, H. Soltner, M. Statera, E. Steffens, H. Stockhorst, H. Ströher, M. Tabidze, G. Tagliente, P. Thörngren Engblom, S. Trusov, Yu. Valdau, A. Vasiliev, P. Wüstner. 2014-07-24. Toward polarized antiprotons: Machine development for spin-filtering experiments. https://doi.org/10.1103/physrevstab.18.020101

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