Longitudinal Spin Transfer to $\Lambda$ Hyperons in Semi-Inclusive Deep Inelastic Scattering with CLAS12

Abstract

The polarization of $\Lambda$ hyperons is preserved in the angular distribution of their decay products. This property allows one to study the spin structure of the $\Lambda$. In Semi-Inclusive Deep Inelastic Scattering where a high energy lepton interacts with a nucleon target and one or more hadrons and the scattered lepton are detected in the final state, the probability for a struck quark to impart the polarization of the lepton to the $\Lambda$ may be measured. In particular, in electron-proton scattering this quantity may be related to the longitudinal light quark polarization of the $\Lambda$. Currently, limited experimental data cannot discriminate between different models of $\Lambda$ spin structure. This work reports on the measurement of the longitudinal spin transfer $D_{L{L}^{\prime }}^{\Lambda }$ to the $\Lambda$ using data taken by the CLAS12 spectrometer at Jefferson Lab with a $10.6$ GeV longitudinally polarized electron beam and an unpolarized hydrogen target. This measurement is the most precise to date, and, in comparison with theory predictions, it offers valuable insight into the relative dominance of current and target fragmentation in $\Lambda$ production.

References in corpus (24)

• Time-reversal odd distribution functions in leptoproduction
• The complete tree-level result up to order $1/Q$ for polarized deep-inelastic leptoproduction
• Parton Fragmentation Functions
• QCD Analysis of Unpolarized and Polarized Lambda - Baryon Production in Leading and Next-to-Leading Order
• First Measurement of Beam-Recoil Observables Cx and Cz in Hyperon Photoproduction
• Asymmetry of Lambda Baryons in Hadronic Z^0 Decays
• Polarized $q\to \Lambda$ Fragmentation Functions from $e^{+}{e}^{-}\to \Lambda +X^{\ast }$
• First Measurement of Transferred Polarization in the Exclusive e p --> e' K+ Lambda Reaction
• Observation of Transverse $\Lambda /\bar{\Lambda }$ Hyperon Polarization in $e^{+}{e}^{-}$ Annihilation at Belle
• Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS
• SIDIS in the target fragmentation region: polarized and transverse momentum dependent fracture functions
• Beam-Recoil Polarization Transfer in the Nucleon Resonance Region in the Exclusive $\vec{e}p\to e^{\prime }{K}^{+}\vec{\Lambda }$ and $\vec{e}p\to e^{\prime }{K}^{+}{\vec{\Sigma }}^0$ Reactions at CLAS
• Longitudinal Spin Transfer to the $\Lambda$ Hyperon in Semi-Inclusive Deep-Inelastic Scattering
• Spin structure and longitudinal polarization of hyperon in e+e- annihilation at high energies
• Expected Polarization of $\Lambda$ particles produced in deep inelastic polarized lepton scattering
• Quark Distributions of Octet Baryons from SU(3) Symmetry
• Structure and Production of Lambda Baryons
• Improved measurement of the longitudinal spin transfer to $\Lambda$ and $\bar{\Lambda }$ hyperons in polarized proton-proton collisions at $\sqrt{s}$ = 200 GeV
• Beam-Recoil Transferred Polarization in $K^{+}Y$ Electroproduction in the Nucleon Resonance Region with CLAS12
• Polarized Lambda hyperon production in Semi-inclusive deep inelastic scattering off an unpolarized nulceon target
• Longitudinal and transverse spin transfer to $\Lambda$ and $\overline{\Lambda }$ hyperons in polarized $p$+$p$ collisions at $\sqrt{s}=200$ GeV
• Suppression of Spin Transfer to $\Lambda$ Hyperon in Deep-Inelastic Scattering
• Longitudinal Spin Transfer to $\Lambda$ Hyperons in CLAS12
• Measurement of Lambda polarization in muon neutrino charged current interactions in NOMAD