Structure and Production of Lambda Baryons

Abstract

We discuss the quark parton structure of the $\Lambda$ baryon and the fragmentation of quarks into $\Lambda$ baryons. We show that the hyperfine interaction, responsible for the $\Delta$-$N$ and ${\Sigma }^0$-$\Lambda$ mass splittings, leads not only to sizeable SU(3) and SU(6) symmetry breaking in the quark distributions of the $\Lambda$, but also to significant polarized non-strange quark distributions. The same arguments suggest flavor asymmetric quark fragmentation functions and non-zero polarized non-strange quark fragmentation functions. The calculated fragmentation functions give a good description of all measured observables. We predict significant positive $\Lambda$ polarization in semi-inclusive DIS experiments while models based on SU(3) flavor symmetry predict zero or negative $\Lambda$ polarization. Our approach also provides a natural explanation for the dependence of the maximum of the $\xi =\ln (1/z)$ spectrum on the mass of the particles produced in $e^{+}{e}^{-}$ annihilation.

24 pages, 9 figures, minor changes

Cited by in corpus (16)

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• Diffractive production of $\Lambda$ hyperons in the high-energy limit of strong interactions
• Measurement of Longitudinal Spin Transfer to Lambda Hyperons in Deep-Inelastic Lepton Scattering
• Transverse Lambda polarization in semi-inclusive DIS
• Longitudinal Spin Transfer to the $\Lambda$ Hyperon in Semi-Inclusive Deep-Inelastic Scattering
• Charge Symmetry Violating Contributions to Neutrino Reactions
• Lambda Polarization in Polarized Proton-Proton Collisions at RHIC
• Connection between Distribution and Fragmentation Functions
• Basis light-front quantization approach to $\Lambda$ and ${\Lambda }_c$ and their isospin triplet baryons
• Next-to-leading order QCD evolution of transversity fragmentation functions
• Nucleon strange $s\bar{s}$ asymmetry to the $\Lambda /\bar{\Lambda }$ fragmentation
• Parton Densities and Fragmentation Functions from Polarized Lambda Production in Semi-Inclusive DIS
• $q\to \Lambda$ Fragmentation Function and Nucleon Transversity Distribution in a Diquark Model
• Detailed Balance and Spin Content of Λ using Statistical Model
• Transverse Lambda polarization in inclusive processes
• Longitudinal Spin Transfer to $\Lambda$ Hyperons in Semi-Inclusive Deep Inelastic Scattering with CLAS12