Measurement of K0S, Lambda, Antilambda production at HERA

Abstract

The production of the neutral strange hadrons $K_S^0$, $\Lambda$ and $\bar{\Lambda }$ has been measured in $ep$ collisions at HERA using the ZEUS detector. Cross sections, baryon-to-meson ratios, relative yields of strange and charged light hadrons, $\Lambda$ ($\bar{\Lambda }$) asymmetry and polarization have been measured in three kinematic regions: $Q^2 > 25 \gev^2$; $5 < Q^2 < 25 \gev^2$; and in photoproduction ($Q^2\simeq 0$). In photoproduction the presence of two hadronic jets, each with at least $5 \gev$ transverse energy, was required. The measurements agree in general with Monte Carlo models and are consistent with measurements made at $e^{+}{e}^{-}$ colliders, except for an enhancement of baryon relative to meson production in photoproduction.

40 pages, 20 figures, 1 table, minor revisions, accepted by European Physical Journal C

References in corpus (30)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• High-Energy-Physics Event Generation with PYTHIA 6.1
• Global QCD Analysis of Parton Structure of the Nucleon: CTEQ5 Parton Distributions
• Successive Combination Jet Algorithm For Hadron Collisions
• Identified Charged Particle Spectra and Yields in Au+Au Collisions at sqrt(s_NN) = 200 GeV
• Improved Parton Distributions from Global Analysis of Recent Deep Inelastic Scattering and Inclusive Jet Data
• Hadronization in heavy ion collisions: Recombination and fragmentation of partons
• Identified particle distributions in pp and Au+Au collisions at sqrt{s_NN}=200 GeV
• LEPTO 6.5 - A Monte Carlo Generator for Deep Inelastic Lepton-Nucleon Scattering
• Identified hadron spectra at large transverse momentum in p+p and d+Au collisions at \sqrts_NN = 200 GeV
• Mid-rapidity $\Lambda$ and $\bar{\Lambda }$ Production in Au+Au Collisions at $\sqrt{s_{{}_{NN}}}=130$ GeV
• Low- and high-mass components of the photon distribution functions
• Measurement of the lambda and lambda^bar particles in Au+Au Collisions at sqrt(s_NN)=130 GeV
• Production of pi+, K+, K0, K*0, phi, p and Lambda-0 in Hadronic Z0 Decays
• Neural Network based Electron Identification in the ZEUS Calorimeter
• Kaon Production and Kaon to Pion Ratio in Au+Au Collisions at $\snn=130$ GeV
• Pentaquarks in high-energy colliding experiments: perspectives from HERA
• Net baryon density in Au+Au collisions at the Relativistic Heavy Ion Collider
• Electroweak instantons/sphalerons at VLHC?
• Jets and Energy Flow in Photon-Proton Collisions at HERA
• Monte Carlo simulation of baryon and lepton number violating processes at high energies
• Search for QCD Instanton-Induced Processes in Deep-Inelastic Scattering at HERA
• K_s^0 and Lambda^0 Production Studies in pbar-p Collisions at sqrt(s)=1800 and 630 GeV
• Baryon Asymmetry of the Proton Sea at Low $x$
• Neutral strange particle production in deep inelastic scattering at HERA
• Strangeness Production in Deep-Inelastic Positron-Proton Scattering at HERA
• Search for QCD-instanton induced events in deep inelastic ep scattering at HERA
• Measurement of Dijet Photoproduction at High Transverse Energies at HERA
• Photoproduction of K^0 and Lambda at HERA and a Comparison with Deep Inelastic Scattering
• Observation of the strange sea in the proton via inclusive Phi-meson production in neutral current deep inelastic scattering at HERA

Cited by in corpus (14)

• Diffractive production of $\Lambda$ hyperons in the high-energy limit of strong interactions
• Extra Spin Asymmetries From the Breakdown of TMD-Factorization in Hadron-Hadron Collisions
• Charged Particle Production in High Q2 Deep-Inelastic Scattering at HERA
• Measurement of (anti)deuteron and (anti)proton production in DIS at HERA
• Measurement of D^{+} and Lambda_{c}^{+} production in deep inelastic scattering at HERA
• The decay width of stringy hadrons
• Production of $\Lambda$ and ${\mathrm{K}}_{\mathrm{S}}^0$ in jets in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV and pp collisions at $\sqrt{s}=7$ TeV
• Deep Exclusive Meson Production as a probe to the puzzle of $\Lambda$ hyperon polarization
• Strangeness Production at low Q^2 in Deep-Inelastic ep Scattering at HERA
• Suppression of Spin Transfer to $\Lambda$ Hyperon in Deep-Inelastic Scattering
• Production of kshort, kstar(892)and phi(1020) in minimum bias events and kshort and lambda in jets in pbar p collisions at sqrt(s)=1.96 TeV
• Production of Lambda, Cascade and Omega Hyperons in ppbar Collisions at1.96 TeV Center of Mass Energy
• Structure Functions
• Global $\Lambda$ hyperon polarization in low-energy heavy ion collisions -- a scenario without vorticity