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arXiv · hep-ex/9708040

Asymmetries Between the Production of Ds- and Ds+ Mesons from 500 GeV/c pi- Nucleon Interactions as Functions of x_F and square of p_t

Abstract

This paper presents measurements of the production of Ds- mesons relative to Ds+ mesons as functions of x_F and square of p_t for a sample of 2445 Ds decays to phi pi. The Ds mesons were produced in Fermilab experiment E791 with 500 GeV/c pi- mesons incident on one platinum and four carbon foil targets. The acceptance-corrected integrated asymmetry in the x_F range -0.1 to 0.5 for Ds+- mesons is 0.032 +- 0.022 +- 0.022, consistent with no net asymmetry. The results, as functions of x_F and square of p_t, are compared to predictions and to the large production asymmetry observed for D+- mesons in the same experiment. These comparisons support the hypothesis that production asymmetries come from the fragmentation process and not from the charm quark production itself.

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E791 Collaboration. 1997-08-28. Asymmetries Between the Production of Ds- and Ds+ Mesons from 500 GeV/c pi- Nucleon Interactions as Functions of x_F and square of p_t. https://doi.org/10.1016/s0370-2693(97)00952-0

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