arXiv subjects

R. G. Ping

Publications and source records attributed to R. G. Ping.

7 recordsLinked to original sources

arXiv2025

Monte Carlo Simulation-Based Partial Wave Analysis of $Ξ_c^+ \to Ξ^-π^+π^+$ Decay

We present a Monte Carlo simulation-based partial wave analysis of the decay $Ξ_c^+ \to Ξ^-π^+π^+$ by using the Feynman-Diagram-Calculation framework. The consistency of the input and output parameters implies the reliability of the partial wave analysis method. A robust method of the spin-parity determination of the $Ξ^{*0}$ resonance is introduced. The rejection significance of the alternative spin-parity hypothesis over the favored hypothesis is strong for different spins, but weak for different parities based on the current integrated luminosity of the Belle experiment. Further data collection is needed to improve the sensitivity of parity determination in the future, e.g., Belle II experiment.

hep-ph↗

arXiv2008

Physics at BES-III

This physics book provides detailed discussions on important topics in $τ$-charm physics that will be explored during the next few years at \bes3 . Both theoretical and experimental issues are covered, including extensive reviews of recent theoretical developments and experimental techniques. Among the subjects covered are: innovations in Partial Wave Analysis (PWA), theoretical and experimental techniques for Dalitz-plot analyses, analysis tools to extract absolute branching fractions and measurements of decay constants, form factors, and CP-violation and \DzDzb-oscillation parameters. Programs of QCD studies and near-threshold tau-lepton physics measurements are also discussed.

hep-ex↗

arXiv2008

Cross sections of e+e- --> gamma VV and e+e- --> gamma gamma V

Cross sections of the e+e- annihilation into one photon plus two vector mesons, such as J/psi rho, J/psi phi, and rho phi at the center of mass energy \sqrt{s}=10.58GeV are calculated. These shed light on the measurement of the e+e- annihilation cross section via radiative return in B-factories. At another center of mass energy \sqrt{s}=3.097GeV, namely the J/psi resonance peak, the processes e+e- --> gamma VV and e+e- --> gamma gamma V (with V being rho, omega, or phi) are calculated with similar method. These calculations give estimation of the background levels in the study of radiative or double radiative decays of J/psi.

hep-ph↗

arXiv2004

Mechanisms for $χ_{cJ}\to ϕϕ$ Decays

Exclusive decays of $χ_{cJ}(J=0,2)$ into $ϕϕ$ are investigated in the framework of perturbative quantum chromodynamics(pQCD) and $\tpz$ quark pair creation model. The results show that these two mechanisms exhibit a quite different behavior in evaluating the decay width for the $χ_{c0}$ and $χ_{c2}$. In pQCD method with nonrelativistic(NR) approximation, while the calculated $\cxpp{2}$ decay width is comparable with measured one, the result for the $\cxpp{0}$ decay width is suppressed and much smaller than experimental value. However, in $\tpz$ quark pair creation model, the situation is reversed: the decay width of $\cxpp{0}$ is greatly enhanced and can reproduce the large measured value, while the contribution to the $\cxpp{2}$ decay width is small. The results suggest that while the pQCD mechanism is the dominant mechanism for $\cxpp{2}$ decay, the $\tpz$ quark pair creation mechanism is the dominant one for $\cxpp{0}$ decay.

hep-ph↗

arXiv2004

A Study of the Roper Resonance as a Hybrid State from $J/ψ$ Decays

The structure of the Roper resonance as a hybrid baryon is investigated through studying the transitional amplitudes in J/psi-> p\barN*, N*\barN* decays. We begin with perturbative QCD to describe the dynamical process for the J/psi-> 3\bar q+3q decay to the lowest order of α_s, and by extending the modified quark creation model to the J/psi energy region to describe the J/psi-> 3\bar q+3q +g process. The non-perturbative effects are incorporated by a simple quark model of baryons to evaluate the angular distribution parameters and decay widths for the processes J/psi-> pbar N*,N*bar N*. From fitting the decay width of J/psi->gamma p pbar to the experimental data, we extract the quark-pair creation strength g_I=15.40 GeV. Our numerical results for J/psi->pbar N*,N* bar N* decays show that the branching ratios for these decays are quite different if the Roper resonance is assumed to be a common $3q$ state or a pure hybrid state. For testing its mixing properties, we present a scheme to construct the Roper wave function by mixing |qqqg> state with a normal |qqq,2s> state. Under this picture, the ratios of the decay widths to that of the J/psi->p pbar decay are re-evaluated versus the mixing parameter. A test of the hybrid nature of the Roper resonance in J/psi decays is discussed.

nucl-th↗

arXiv2003

CP Test in J/Psi -> gamma phi phi Decay

We propose to test CP symmetry in the decay $\jp\to γϕϕ$, for which large data sample exists at BESII, and a data sample of $10^{10}$ $J/ψ$'s will be collected with BESIII and CLEO-C program. We suggest some CP asymmetries in this decay mode for CP test. Assuming that CP violation is introduced by the electric- and chromo-dipole moment of charm quark, these CP asymmetries can be predicted by using valence quark models. Our work shows a possible way to get information about the electric- and chromo-dipole moment of charm quark, which is little known. Our results show that with the current data sample of $J/ψ$, electric- and chromo-dipole moment can be probed at order of $10^{-14}e cm$. In the near future with a $10^{10}$ data sample, these moments can be probed at order of $10^{-16}e cm$.

hep-ph↗

arXiv2001

Study of N*(1440) from J/Psi Decays

For $J/Ψ\to\bar pp π^0$ and $\bar ppπ^+π^-$, the $π^0p$ and $pπ^+π^-$ systems are limited to be pure isospin 1/2 due to isospin conservation. This is a big advantage in studying $N^*$ resonances from $J/Ψ$ decays, compared with $πN$ and $γN$ experiments. The process $J/Ψ\to\bar pN^*$ or $p\bar N^*$ provides a new way to probe the internal structure of the $N^*$ resonances. Here we report a quark model calculation for $J/Ψ\to\bar pp$, $pN^*(1440)$ and $\bar N^*N^*$. The implication for the internal structure of $N^*(1440)$ is discussed.

hep-ph↗