Single-Spin Asymmetry in Inclusive $π^0$ Production Measured at the Protvino 70 GeV Accelerator

A. Davidenko; V. Grishin; V. Khodyrev; V. Kravtsov; Yu. Matulenko; V. Medvedev; Yu. Melnick; A. Meschanin; V. Mochalov; D. Morozov; L. Nogach; S. Nurushev; P. Semenov; K. Shestermanov; L. Soloviev; A. Vasiliev; A. Yakutin; N. Borisov; A. Fedorov; V. Matafonov; A. Neganov; Yu. Plis; Yu. Usov; A. Lukhanin

arXiv · hep-ex/0312014

Single-Spin Asymmetry in Inclusive $π^0$ Production Measured at the Protvino 70 GeV Accelerator

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Abstract

Single Spin Asymmetries (SSA) $A_N$ measured in the two reactions at the Protvino 70 GeV accelerator are presented. $A_N$ in the reaction $p+p(pol)->π^0+X$ in the central region is close to zero within the error bars. SSA in the reaction $π^- +p(pol)->π^0+X$ in the polarized target fragmentation region is equal to $(-15 \pm 4)%$ at $|x_F|>0.4$. There is an indication that the asymmetry arises at the same pion energy in the center of mass system.

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A. Davidenko, V. Grishin, V. Khodyrev, V. Kravtsov, Yu. Matulenko, V. Medvedev, Yu. Melnick, A. Meschanin, V. Mochalov, D. Morozov, L. Nogach, S. Nurushev, P. Semenov, K. Shestermanov, L. Soloviev, A. Vasiliev, A. Yakutin, N. Borisov, A. Fedorov, V. Matafonov, A. Neganov, Yu. Plis, Yu. Usov, A. Lukhanin. 2003-12-03. Single-Spin Asymmetry in Inclusive $π^0$ Production Measured at the Protvino 70 GeV Accelerator. https://arxiv.org/abs/hep-ex/0312014

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