相关论文: Spin alignments of vector mesons in deeply inelast…
Recent e+e- annihilation experiments show a striking spin alignment of vector mesons produced in the fragmentation of a polarized quark.We show that these data imply a simple relation between the polarization of the anti-quark, which is…
Using the same method as that used in $e^+e^-$ annihilation and lepton-nucleon deep-inelastic scattering, we calculate the spin alignment of vector mesons with high transverse momenta in high energy $pp$ collisions with one longitudinally…
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,…
The possible role played by vector mesons in inclusive deep inelastic lepton-nucleon scattering is investigated. In the context of the convolution model, we calculate self-consistently the scaling contribution to the nucleon structure…
A detailed study of fragmentation of vector mesons at the next-to-leading order (NLO) is given for e^+ e^- scattering. A model with broken SU(3) symmetry uses three input fragmentation functions \alpha(x, Q^2), \beta(x,Q^2) and…
Recent measurements, in particular those on $\Lambda$ polarization and spin alignment of vector mesons in $e^+e^-$ annihilation at LEP, and those on the azimuthal asymmetry at HERA, have attracted much attention on the spin effects in high…
We explain how spin alignment of vector mesons can be induced by background fields, such as electromagnetic fields or soft gluon fields. Our study is based on the quantum kinetic theory of spinning quarks and antiquarks and incorporates the…
The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). It provides a unique opportunity to probe the correlation between…
Spin transfer in high energy fragmentation process is determined by the hadronization mechanism and spin structure of hadrons.It can be studied by measuring the polarizations of hyperons and/or vector mesons in e+e- annihilation, in the…
We study the deep inelastic structure functions of mesons within the Nambu and Jona-Lasinio model. We calculate the valence quark distributions in $\pi $, $K $, and $\rho $ mesons at the low energy model scale, which are evoluted to the…
We calculate the spin density matrix of the vector meson produced in e+e- annihilation at Z^0 pole. We show that the data imply a significant polarization for the antiquark which is created in the fragmentation process of the polarized…
The recent data on the polarization of vector meson at LEP show that the vector mesons favor the helicity zero state. We calculate the helicity density matrix of vector meson which contains a polarized fragmenting quark by adding the spin…
This review covers the recent experimental development on spin alignment measurements of $K^{*0}$ and $\phi$ vector mesons in heavy-ion and pp collisions at RHIC and LHC energies. Measurements in $e^+e^-$ collisions at LEP energies are also…
We calculate the process-independent fragmentation functions for a $\bar b$ antiquark to fragment into longitudinally and transversely polarized $B_c^*$ ($^3S_1$) mesons to leading order in the QCD strong coupling constant. In the special…
We discuss the target and beam normal spin asymmetries in elastic electron-nucleon scattering which depend on the imaginary part of two-photon exchange processes between electron and nucleon. We express this imaginary part as a phase space…
We estimate the target-normal single-spin asymmetry at nearly forward angles in elastic electron-nucleon scattering. In the leading-order approximation, this asymmetry is proportional to the imaginary part of the two-photon exchange (TPE)…
Within the impulse approximation, we derive expressions for the amplitude of deeply virtual Compton scattering on spinless nuclei in terms of the generalized parton distributions of the nucleon. As an application, nuclear effects in the…
We calculate the polarizations for different octet hyperons produced in the current fragmentation regions of the deeply inelastic lepton-nucleon scatterings $\mu^-N \to \mu^- HX$ and $\nu_{\mu} N \to \mu^- HX$ at high energy using different…
The production of hadrons in polarized lepton-nucleon deep inelastic scattering is discussed. The helicity density matrix of the hadron is computed within the QCD hard scattering formalism and its elements are shown to yield information on…
We present results for all leading-twist azimuthal spin asymmetries in semi-inclusive lepton-nucleon deep-inelastic scattering due to T-even transverse-momentum dependent parton distribution functions on the basis of a light-cone…