The quark-antiquark asymmetry of the nucleon sea from Lambda and (Lambda)over-bar fragmentation

Ma, BQ; Schmidt I.; Soffer, J; Yang, JJ

Abstract

We present a general analysis of the spin transfer for Lambda and <(Lambda)over bar> production in deep-inelastic scattering of polarized charged leptons on the nucleon, and find that the pattern of different behaviors of Lambda and <(Lambda)over bar> production observed by the E665 Collaboration suggests the possibility of quark-antiquark asymmetries either in the quark to Lambda fragmentation functions and/or in the quark and antiquark distributions of the target proton. We also point out that the strange-antistrange asymmetry of the nucleon sea may produce an observable contribution to the different behaviors of Lambda and <(Lambda)over bar> production. We find that a softer (s) over bar(x) than s(x) as predicted by the light-cone baryon-meson fluctuation model of intrinsic quark-antiquark pairs of the nucleon sea might lead to a reasonable picture. However, the magnitude is still too small to explain the E665 data and the conclusion has also strong model-dependence. This may suggest the importance of quark-antiquark asymmetry in the quark to Lambda fragmentation functions, provided that the E665 data are confirmed. (C) 2000 Elsevier Science B.V. All rights reserved.

Más información

Título según WOS: The quark-antiquark asymmetry of the nucleon sea from Lambda and (Lambda)over-bar fragmentation
Título de la Revista: PHYSICS LETTERS B
Volumen: 488
Número: 3-4
Editorial: ELSEVIER SCIENCE BV
Fecha de publicación: 2000
Página de inicio: 254
Página final: 260
Idioma: English
URL: http://linkinghub.elsevier.com/retrieve/pii/S0370269300009400
DOI:

10.1016/S0370-2693(00)00906-0

Notas: ISI