The quark-antiquark asymmetry of the nucleon sea from ? and ?? fragmentation

Ma, B.-Q.; Schmidt I.; Yang J.-J.; Soffer, J

Keywords: model, lepton, physics, scattering, quark, prediction, radiation, nucleon, nuclear, particle, baryon, article, elementary, mathematical, antiquark

Abstract

We present a general analysis of the spin transfer for ? and ?? production in deep-inelastic scattering of polarized charged leptons on the nucleon, and find that the pattern of different behaviors of ? and ?? production observed by the E665 Collaboration suggests the possibility of quark-antiquark asymmetries either in the quark to ? 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 ? and ?? production. We find that a softer s?(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 ? fragmentation functions, provided that the E665 data are confirmed. (C) 2000 Elsevier Science B.V.

Más información

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
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-0034618417&partnerID=q2rCbXpz