Asymmetries in the production of Λc+ and Λc− baryons in 500 GeV/c π− nucleon interactions

doi:10.1016/S0370-2693(00)01239-9

Physics Letters B

Volume 495, Issues 1–2, 7 December 2000, Pages 42-48

https://doi.org/10.1016/S0370-2693(00)01239-9 Get rights and content

Abstract

We present a measurement of asymmetries in the production of Λ_c⁺ and Λ_c⁻ baryons in 500 GeV/c π⁻-nucleon interactions from the E791 experiment at Fermilab. The asymmetries were measured as functions of Feynman x (x_F) and transverse momentum squared (p_T²) using a sample of $1 819±62$ Λ_c's observed in the decay channel Λ_c⁺→pK⁻π⁺. We observe more Λ_c⁺ than Λ_c⁻ baryons, with an asymmetry of (12.7±3.4±1.3)% independent of x_F and p_T² in our kinematical range (−0.1⩽x_F⩽0.6 and 0.0⩽p_T²⩽8.0 (GeV/c)²). This Λ_c asymmetry measurement is the first with data in both the positive and negative x_F regions.

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Acknowledgements

We gratefully acknowledge the assistance of the staffs of Fermilab and of all the participating institutions. This research was supported by the Brazilian Conselho Nacional de Desenvolvimento Cientı́fico e Tecnológico, CONACyT (Mexico), the U.S.–Israel Binational Science Foundation, the U.S. Department of Energy and the U.S. National Science Foundation. Fermilab is operated by the Universities Research Associates, Inc., under contract with the U.S. Department of Energy.

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Asymmetries in the production of Λc+ and Λc− baryons in 500 GeV/c π− nucleon interactions

Abstract

Section snippets

Acknowledgements

Nucl. Phys. B

Eur. Phys. J. C

Comput. Phys. Commun.

Eur. Phys. J. C

Phys. Rev. Lett.

Annu. Rev. Nucl. Part. Sci.

Nucl. Instrum. Methods A

Asymmetries in the production of Λ_c⁺ and Λ_c⁻ baryons in 500 GeV/c π⁻ nucleon interactions