Related papers: Spin effects in vector meson production at LEP
Parity-violating (pv) effects in inclusive hadron and jet productions in high energy hadron-hadron collisions are analyzed. Such effects arise from the interference between strong and weak amplitudes. This interference gives rise to a…
The three different helicity states of W bosons produced in the reaction e+ e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to measure the…
Quark spin effects in $e^+e^-$ annihilation to pseudoscalar and vector mesons are implemented for the first time in the PYTHIA Monte Carlo event generator. The spin-dependent fragmentation of the string stretched between the produced…
We present the measurements related to the spin alignment of $\mathrm{K^{*0}}$ and $\mathrm{\phi}$ vector mesons at mid-rapidity for Pb--Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV using the ALICE detector at the LHC. The second…
The BESIII collaboration here reports the first observation of polarized $\Lambda$ and $\bar{\Lambda}$ hyperons produced in two different processes: i) the resonant $e^+e^- \to J/\psi\to\Lambda\bar{\Lambda}$, using a data sample of 1.31…
The final-state interaction effects on the inclusive two-particle production in electron-positron annihilation are investigated within the context of the one-photon annihilation approximation. Such effects are characterized by one structure…
Possible oblique effects from vector particles that are strongly coupled to the known gauge bosons are calculated for the case of final hadronic states produced at future $e^+e^-$ colliders, using a formalism that was recently proposed and…
The spin alignment of vector meson produced in high energy reactions is determined by the spin-dependent fragmentation function $D_{1LL} (z,\mu_f)$ that is shown to be independent of the polarization of the fragmenting quark. In this paper,…
We establish a connection between the distribution functions of quarks in spin-one hadrons and the helicity matrix for forward scattering of antiquarks off spin-one hadrons. From positivity of this matrix we obtain inequality relations…
Predictions of a thermodynamical model of hadron production for multiplicity distributions in $e^+e^-$ annihilations at LEP and PEP-PETRA centre of mass energies are shown. The production process is described as a two-step process in which…
We apply a generalized spin-basis analysis to associated Higgs production and gauge boson pair production at LEP. This framework allows us to identify a choice of spin axes for the processes e+ e- --> ZH,ZZ which leads to strikingly…
We present new measurements related to spin alignment of $\mathrm{K^{*0}}$ vector mesons at mid-rapidity for Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 and 5.02 TeV. The spin alignment measurements are carried out with respect to…
The purpose of the ALICE experiment at the LHC is the study of the Quark Gluon Plasma (QGP) formed in ultra-relativistic heavy-ion collisions, a state of matter in which quarks and gluons are deconfined. The properties of this state of…
We study the potential of the CERN Large Hadron Collider (LHC) to probe the spin of new massive vector boson resonances predicted by Higgsless models. We consider its production via weak boson fusion which relies only on the coupling…
We investigate the spin alignment of vector mesons arising from locally polarized quarks and anti-quarks (local spin alignment) in heavy-ion collisions. We find that $\rho_{00}\neq 1/3$ does not necessarily signal the global polarization of…
We develop a quantum spin-density-matrix framework for heavy-quark spin dynamics in relativistic heavy-ion collisions. Starting from an initial polarization induced along the magnetic-field direction, we derive the evolution equation for…
We discuss the spin structure of the proton in a light-cone treatment of the chiral quark model. Based on the fact that the quark helicity ($\Delta q$) measured in polarized deep inelastic scattering experiments is actually the quark spin…
The special role played by singly polarized high-energy hadron-hadron collisions in Spin Physics is discussed: In such processes, the measured and the calculated quantities can be and have been directly compared with each other --- without…
In this short note I speculate on some consequences of the high energy collision picture in which the orbital angular momentum of the colliding hadrons can be converted into secondary particle angular spin momentum via some spin-orbital…
The hadron production in $e^+e^-$ collisions is studied assuming that particles originate in a hadron gas at thermal and chemical equilibrium. The parameters of the hadron gas are determined with a fit to the average multiplicities of…