Ratio of Λ / Λ in Semi - inclusive Electroproduction
نویسندگان
چکیده
It is shown that the Λ/Λ cross section ratio in semi-inclusive electroproduction of Λ and Λ hyperons in deep inelastic scattering of charged lepton on a nucleon target, can provide useful information on the quark to Λ fragmentation functions. This ratio is calculated explicitly in a quark-diquark model, a pQCD based analysis, and an SU(3) symmetry model, with three different options for the contribution from the unfavored fragmentation functions. The x-dependence of this ratio is sensitive to the ratio of unfavored fragmentation functions over favored fragmentation functions, DΛ u (z)/D Λ u (z), whereas the z-dependence is sensitive to the flavor structure of the fragmentation functions, i.e., the ratio DΛ u (z)/D Λ s (z). Future measurements by the HERMES Collaboration at DESY can discriminate between various cases.
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