相关论文: Ratio of $\bar{\Lambda}/\Lambda$ in Semi-inclusive…
It is shown that the dependence of ratio $f_s/f_d$ could be understood within the fragmentation approach. However, the validity of fragmentation model is questionable at low $p_T$, and contributions of nonfragmentation mechanisms are…
We briefly report our recent progress on the study of the polarized fragmentation functions of $\Lambda$ hyperon in unpolarized semi-inclusive deep-inelastic scatterings and electron-positron annihilations at low energies. In particular, we…
The longstanding problem of explaining the observed polarization of Lambda hyperons inclusively produced in the high energy collisions of unpolarized hadrons is tackled by considering spin and k_T dependent quark fragmentation functions.…
We present the results of a nonrelativistic constituent quark model study of the semileptonic decays $\Lambda_b^0 \to \Lambda_c^+ l^- {\bar \nu}_l$ and $\Xi_b^0 \to \Xi_c^+ l^- {\bar \nu}_l$. We work on coordinate space, with baryon wave…
The form factor of Lambda_b^0 baryons is estimated using 3.46 10^6 hadronic Z decays collected by the DELPHI experiment between 1992 and 1995. Charmed Lambda_c^+ baryons fully reconstructed in the pK-pi+, pK0_S, and Lambda pi+pi+pi- modes,…
We discuss production of charmed mesons as well as electrons/muons from semileptonic decays of charm and bottom mesons in proton-proton collisions at the LHC. The cross section for inclusive production of $c \bar c$ and $b \bar b$ pairs is…
The heavy quark effective theory makes model independent predictions for semileptonic $\Lambda_b \to \Lambda_c$ decays in terms of a small set of parameters. No subleading Isgur-Wise function occurs at order $\Lambda_{\rm QCD}/m_{c,b}$, and…
Fracture functions, originally suggested to describe the production of diffractive and leading hadrons in semi-inclusive DIS, may be also applied at fixed target energies. They may also include interference and final state interaction,…
Following a previous description of Lambda and Lambda-bar polarization in unpolarized p-p interactions, within a perturbative QCD factorization scheme with new polarizing fragmentation functions, here we investigate the transverse…
A large set of cross sections for semi-inclusive electroproduction of charged pions ($\pi^\pm$) from both proton and deuteron targets was measured. The data are in the deep-inelastic scattering region with invariant mass squared $W^2$ > 4…
Heavy baryon/meson ratios $\Lambda_c/D^0$ and $\Lambda_b/\bar{B}^0$ in relativistic heavy ion collisions are studied in the quark coalescence model. For heavy baryons, we include production from coalescence of heavy quarks with free light…
We study the transverse polarization of hyperons produced in semi-inclusive deep inelastic scattering, $ep\to e\Lambda^\uparrow X$, in the framework of the collinear twist-3 factorization. The cross section from the twist-3 distribution…
Understanding the properties of the strange $\Lambda^*$ baryon resonances is a long-standing and fascinating problem. $\Lambda_c$ charm-baryon semileptonic weak decays to these resonances are highly sensitive to their internal structure and…
A summary of measurements of the fragmentation of charm quarks into a specific hadron is given. Measurements performed in photoproduction and deep inelastic scattering in $e^{\pm}p$, $pp$ and $e^+e^-$ collisions are compared, using…
The tree-level $b\rightarrow c{\ell}\bar\nu_{\ell}$ based hadronic transitions have been on the focus of much attention since recording significant deviations of the experimental data, on the ratios of the branching fractions in $ \tau $…
We present results for the quasi-elastic weak production of $\Lambda$ and $\Sigma$ hyperons induced by $\bar{\nu}$ scattering off nuclei, in the kinematical region of interest for accelerator neutrino experiments. We employ realistic hole…
New results on charm and beauty electroproduction from the H1 and ZEUS Collaborations at the ep collider HERA are presented. Differential cross sections are compared to a next-to-leading order QCD calculation. The heavy quark contributions,…
We calculate the semi-leptonic decays of $\Lambda_c$ and $\Lambda_b$ baryons which involve transitions of a heavy quark to a light quark. In a previous work we used data on the Cabibbo favoured non-leptonic decays of charmed baryons…
We present new sets of nonperturbative fragmentation functions for D^0, D^+, and D_s^+ mesons as well as for Lambda_c^+ baryons, both at leading and next-to-leading order in the MSbar factorization scheme with five massless quark flavors.…
Rapidity distributions for $\Lambda$ and $\bar{\Lambda}$ hyperons in central Pb-Pb collisions at 40, 80 and 158 A$\cdot$GeV and for ${\rm K}_{s}^{0}$ mesons at 158 A$\cdot$GeV are presented. The lambda multiplicities are studied as a…