相关论文: Helicity Analysis of Semileptonic Hyperon Decays I…

Because quarks in hadronic states are subjected to strong QCD forces, it is not straight-forward to apply calculation obtained at the quark level to physical processes involving hadrons. In this paper we present a new approach to treat the…

We perform a helicity amplitude analysis for the processes of $e^+e^-$$\rightarrow$$J/\psi,\psi(2S)\rightarrow\Xi(1530)\bar\Xi(1530)\rightarrow\pi\pi\Xi\bar\Xi\rightarrow\Lambda\bar\Lambda4\pi\rightarrow p\bar{p}6\pi$. The joint angular…

We explain how angular correlations in leptonic decays of vector bosons and top quarks can be included in Monte Carlo parton showers, in particular those matched to NLO QCD computations. We consider the production of $n$ pairs of leptons,…

Status of tau lepton decay Monte Carlo generator TAUOLA, its main applications and recent developments are reviewed. It is underlined, that in recent efforts on development of new hadronic currents, the multi-dimensional nature of…

Monte Carlo evaluation is used to calculate heavy-ion elastic scattering including the center-of-mass correction and the Coulomb interaction.Angular distributions are presented for a number of nuclear pairs over a wide energy range using…

We study the semileptonic decays of heavy mesons into light pseudoscalars by making use of dispersion relations. Constraints from heavy quark symmetry, chiral symmetry and perturbative QCD are implemented into a dispersive model for the…

Determining the spin of any new particle and measuring its couplings to other particles and/or itself are crucial in reconstructing the structure of any quantum field theory containing the particle. A general helicity formalism is employed…

We consider identical particle and lepton mass effects in the cascade decay $H\to Z^\ast(\to\tau^+\tau^-)+Z^\ast(\to\tau^+\tau^-)$. Since the scale of the problem is set by the off-shellness $p_a^2$ and $p_b^2$ of the respective gauge…

The helicity-dependent strange quark distribution in the proton, $\Delta s$, is calculated in a nonlocal chiral SU(3) effective field theory. The hadronic proton to meson plus octet or decuplet baryon splitting functions are derived at the…

Recent measurements of the lepton flavor universality ratios $R^{\mu e}_{K}$ and $R^{\mu e}_{K^*}$ in $B\to \left(K, K^*\right)\mu^{+}\mu^{-}\left(e^+e^-\right)$ at LHCb align with the Standard Model predictions, necessitating search for…

We study the semileptonic decays of $\Xi^{(')}_{b}\rightarrow\Xi^{(')}_{c}{\ell}\bar\nu_{\ell}$ in all lepton channels. To do this, we first obtain the form factors defining these decay modes within the framework of QCD sum rules. Then,…

We study the full angular distribution of semileptonic rare charm baryon decays in which the secondary baryon undergoes weak decay with sizable polarization parameter, $\Xi_c^+\to\Sigma^+\,(\to p\pi^0)\ell^+\ell^-$,…

We propose an approach for measuring the moments of the hadronic invariant mass distribution in semileptonic $B_{s}^{0}$ meson decays using a sum-of-exclusive technique. Using the present and foreseen knowledge about exclusive semileptonic…

We investigate the semileptonic decays of baryons containing double charm or double bottom quarks, focusing on their transitions to single heavy baryons through three-point QCD sum rule framework. In our calculations, we take into account…

We report an analytical and numerical investigation into the impact of helicity inversion in LHC processes that do not conserve lepton number $(L)$. As a case study, we focus on the production and decay of Majorana neutrinos $(N)$ through…

A measurement of the inclusive semileptonic branching ratios of b hadrons produced in Z decay is presented, using four million hadronic events collected by the ALEPH detector from 1991 to 1995. Electrons and muons are selected opposite to…

We consider the hadroproduction of chi_{c1} and chi_{c2} mesons and their subsequent radiative decays to J/psi mesons and photons in the factorization formalism of nonrelativistic quantum chromodynamics, and study the decay angular…

We analyze the tauonic semileptonic baryon decays $\Lambda^0_b \to \Lambda^+_c + \tau^{-} +\bar \nu_{\tau}$ with particular emphasis on the lepton helicity flip contributions which vanish for zero lepton masses. We calculate the total rate,…

We study the possibility of finding the axion-like particles (ALPs) through the leptonic decays of heavy mesons. The Standard Model (SM) predictions of the branching ratios of the leptonic decays of heavy mesons are less than the…

Analytic formulae are given for QCD corrections to the lepton spectra in decays of polarised up and down type heavy quarks. These formulae are much simpler than the published ones for the corrections to the spectra of charged leptons…