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arXiv · 1611.07365

Leading Neutrons From Polarized Proton-Nucleus Collisions

B. Z. Kopeliovich·I. K. Potashnikova·Ivan Schmidt
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Abstract

Leading neutron production on protons is known to be subject to strong absorptive corrections, which have been under debate for a long time. On nuclear targets these corrections are significantly enhanced and push the partial cross sections of neutron production to the very periphery of the nucleus. As a result, the A-dependences of inclusive and diffractive neutron production turn out to be similar. The mechanism of π-a_1 interference, which successfully explained the observed single-spin asymmetry of neutrons in polarized pp interactions, is extended here to polarized pA collisions. Corrected for nuclear effects it explains well the magnitude and sign of the asymmetry A_N observed in inelastic events, resulting in a violent break up of the nucleus. However the excessive magnitude of A_N observed in the diffractive sample, remains a challenge.

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B. Z. Kopeliovich, I. K. Potashnikova, Ivan Schmidt. 2016-11-21. Leading Neutrons From Polarized Proton-Nucleus Collisions. https://doi.org/10.1063/1.4977154

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