相关论文: The width difference of rho vector mesons
We present a unified model describing electroweak properties of the pi and rho mesons. Using a general method of relativistic parametrization of matrix elements of local operators, adjusted for the nondiagonal in total angular momentum…
We calculate the width for the omega -> pi pi decay in nuclear matter in a hadronic model including mesons, nucleons and Delta isobars. We find a substantial width of the longitudinally polarized omega modes, reaching ~100MeV for mesons…
High precision measurements of the differential cross sections for $\pi^0$ photoproduction at forward angles for two nuclei, $^{12}$C and $^{208}$Pb, have been performed for incident photon energies of 4.9 - 5.5 GeV to extract the ${\pi^0…
The photoproduction of vector mesons on various nuclei has been studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory. The vector mesons, $\rho$, $\omega$, and $\phi$, are observed via their decay to $e^+e^-$,…
We measure the mass difference, \Delta m_0, between the D*(2010)+ and the D0 and the natural line width, \Gamma, of the transition D*(2010)+ -> D0 pi+. The data were recorded with the BABAR detector at center-of-mass energies at and near…
The couplings and decay widths of the proceses (1^+,2^+)->(0^-,1^-)+rho are studied with ligh-cone QCD sum rules in the leading order of heavy quark effective theory. These processes are employed to estimate the two pion transition widths…
We report measurements of the $\pi^- p \to \pi^o n$ differential cross sections at six momenta (104-143 MeV/c) and four angles (0-40 deg) by detection of $\gamma$-ray pairs from $\pi^o \to \gamma \gamma$ decays using the TRIUMF RMC…
This study revisits the issue of the extraction of estimates for the masses and for the partial decay widths to two pions of the scalar-isoscalar $I^G\,(J^{PC}) = 0^+\,(0^{++})$ and vector-isovector $I^G\,(J^{PC}) = 1^+\,(1^{--})$ mesons…
The influence of the finite width of $\rho$ meson on the pion momentum distribution is studied quantitatively in the framework of the S-matrix approach combined with a blast-wave model to describe particle emissions from an expanding…
The mass shift and width broadening of rho-mesons produced in heavy ion collisions is estimated using general formulae which relate the in-medium mass shift of a particle to the real part of the forward scattering amplitude of this particle…
Qualitative changes in the collective excitation spectra of the $\rho$-meson triplet in neutron matter is studied, with particular emphasis on the breaking of the discrete $p\leftrightarrow n$ symmetry. The appearance of additional branches…
The rho meson spectral function in hot and dense asymmetric nuclear matter (number densities of proton and neutron different) is evaluated in an effective chiral SU(3) model within the mean field approximation (MFA). The dependence of the…
The decay width of the $\omega$ meson at finite temperature is calculated using the Gell-Mann Sharp Wagner model of $\rho$ pole dominance. Effective masses of the $\rho$ and $\omega$ are determined within the framework of real-time…
It is known that the decay process \eta\rightarrow\pi^0\pi^+\pi^- in free space is possible due to the isospin-symmetry breaking in Quantum Chromodynamics (QCD), i.e., the small mass difference between u and d quarks: The small width is…
The (Delta I = 1) decay D_s^* --> Ds pi0 and (\Delta I = 0) decay D_s^* --> Ds gamma have been reconstructed using 90.4 fb^-1 of data recorded by the BaBar detector at the PEP-II asymmetric-energy e^+e^- collider. The relative branching…
Motivated by recent results from Higgs searches at the Large Hadron Collider, we consider possibilities to enhance the diphoton decay width of the Higgs boson over the Standard Model expectation, without modifying either its production rate…
We study the strong and radiative decays of the radial excitation of the $\rho$ meson, with quantum numbers $n$ $^{2S+1}L_{J}=2$ $^{3}S_{1},$ $I=1$, and denoted as $\rho_{E}$, by making use of an effective model. We test different masses:…
The relations between masses and decay constants of variety of meson resonances in the energy range 0--3 GeV are verified from the string-like, linear mass spectrum for vector, axial-vector, scalar and pseudoscalar mesons with a universal…
The charge asymmetry induced by interference of amplitudes with $\sigma$ and $\rho$ mesons decaying to $\pi^+\pi^-$ pair created in the fragmentation region of proton, suggest to be a test of degeneration hypothesis of $\rho$ and $\sigma$…
This work focuses on decomposition of isospin amplitude of D meson non-leptonic decays. Isospin vector algebra is used to show the equivalency of two amplitude decompositions. We restrict to the transitions involving only Del I = 1 and Del…