Quark Structure of $\Lambda$ from $\Lambda$-Polarization in Z Decays

Abstract

The flavor and spin structure for the quark distributions of the $\Lambda$-baryon is studied in a perturbative QCD (pQCD) analysis and in the SU(6) quark-diquark model, and then applied to calculate the $\Lambda$-polarization of semi-inclusive $\Lambda$ production in $e^{+}{e}^{-}$-annihilation near the $Z$-pole. It is found that the quark-diquark model gives very good description of the available experimental data. The pQCD model can also give good description of the data by taking into account the suppression of quark helicities compared to the naive SU(6) quark model spin distributions. Further information is required for a clean distinction between different predictions concerning the flavor and spin structure of the $\Lambda$.

25 latex pages, eight eps figures, small changes in references and discussions, final version to be published in PRD 61(2000)

References in corpus (2)

• Melosh rotation: source of the proton's missing spin
• Structure and Production of Lambda Baryons

Cited by in corpus (41)

• Prospects for Spin Physics at RHIC
• Flavor and Spin Structure of $\Lambda$-Baryon at Large x
• The Flavor and Spin Structure of Hyperons from Quark Fragmentation
• Nucleon Transversity Distribution from Azimuthal Spin Asymmetry in Pion Electroproduction
• Measurement of Longitudinal Spin Transfer to Lambda Hyperons in Deep-Inelastic Lepton Scattering
• Spin structure and longitudinal polarization of hyperon in e+e- annihilation at high energies
• Leading and higher twist contributions in semi-inclusive e+e- annihilation at high energies
• Tensor polarization dependent fragmentation functions and e+e-\to V πX at high energies
• Helicity and Transversity Distribution of Nucleon and $\Lambda$-Hyperon from $\Lambda$ Fragmentation
• Quark Distributions of Octet Baryons from SU(3) Symmetry
• Spin alignment of vector meson in e+e- annihilation at Z0 pole
• Statistical approach for unpolarized fragmentation functions for the octet baryons
• Lambda Polarization in Polarized Proton-Proton Collisions at RHIC
• Anti-Lambda polarization in high energy pp collisions with polarized beam
• Hyperon polarization in semi-inclusive deeply inelastic lepton-nucleon scattering at high energy
• Basis light-front quantization approach to $\Lambda$ and ${\Lambda }_c$ and their isospin triplet baryons
• Connection between Distribution and Fragmentation Functions
• Energy dependence of hadron polarization in $e^{+}{e}^{-}\to hX$ at high energies
• Sea quark contents of octet baryons
• Next-to-leading order QCD evolution of transversity fragmentation functions
• The Spin Alignment of Vector Mesons in High Energy pp Collisions
• Hyperon polarization in ν_μcharged current interaction at the NOMAD energies
• Spin Transfers for Baryon Production in Polarized pp Collisions at RHIC-BNL
• Several Topics on Transverse Momentum-Dependent Fragmentation Functions
• Up and Down Quark Contributions to Spin Content of Lambda from Fragmentation
• Quark to $\Lambda$-hyperon spin transfers in the current-fragmentation region
• Flavor and Spin Structure of Octet Baryons at Large x
• The Quark-Antiquark Asymmetry of the Nucleon Sea from $\Lambda$ and $\bar{\Lambda }$ Fragmentation
• Anti-Hyperon polarization in high energy pp collisions with polarized beams
• Spin alignment of the high $p_T$ vector mesons in polarized pp collisions at high energies
• $q\to \Lambda$ Fragmentation Function and Nucleon Transversity Distribution in a Diquark Model
• Spin transfer and polarization of antihyperons in lepton induced reactions
• Phenomenological Relation between Distribution and Fragmentation Functions
• Quark Fragmentation Functions in a Diquark Model for $\Lambda$ Production
• Strange quark-antiquark asymmetry of nucleon sea from $\Lambda /\bar{\Lambda }$ polarization
• Nucleon strangeness polarization from $\Lambda /\bar{\Lambda }$ hyperon production in polarized proton-proton collision at RHIC
• Ratio of $\bar{\Lambda }/\Lambda$ in Semi-inclusive Electroproduction
• Evidence for SU(3) symmetry breaking from hyperon production
• The longitudinal polarization of hyperons in the forward region in polarized $pp$ collisions
• Hyperon polarization in e^-p --> e^-HK with polarized electron beams
• Particle-Antiparticle Asymmetries of $\Lambda$ Production in Hadron-Nucleon Collisions