相关论文: Pinpointing Physical Solutions in Y(4230) Decays
We review here the physics of purely leptonic decays of pi-, K-, D+, Ds+, and B- pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak interaction based CKM matrix element of the constituent quarks…
We study the decay processes $B \to K \pi$ by using generalized decay amplitudes with both the final state re-scattering strong phases and the topological quark diagrammatic strong phases included together as part of fitting parameters.…
e+e- experiments at charmonium production threshold are reviewed, it is found that the contribution of the continuum process via virtual photon has been neglected in almost all the experiments and most channels analyzed. It is pointed out…
Based on $5.8 \times 10^7 J\psi$ events collected with BESII at the Beijing Electron-Positron Collider (BEPC), the decay branching fractions of $J\psi\to\omega\pi^0$, $\omega\eta$, and $\omega\eta'$ are measured using different $\eta$ and…
The cross section of the process $e^+e^-\to \pi^+D^0D^{*-}$ for center-of-mass energies from 4.05 to 4.60~GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements…
We study the pseudogaps in the spectra of the half-filled 2D Hubbard model using both finite-size and dynamical cluster approximation (DCA) quantum Monte Carlo calculations. A charge pseudogap, accompanied by non-Fermi liquid behavior in…
In the collider phenomenology of extensions of the Standard Model with partner particles, cascade decays occur generically, and they can be challenging to discover when the spectrum of new particles is compressed and the signal cross…
We report a study of the process gamma gamma -> X -> eta_c pi+ pi-, where X stands for one of the resonances chi_{c2}(1P), eta_c(2S), X(3872), X(3915), or chi_{c2}(2P). The analysis is performed with a data sample of 473.9 fb^{-1} collected…
We have measured the $\pi^+\to {\rm e}^+\nu\gamma$ branching ratio over a wide region of phase space, based on a total of 65,460 events acquired using the PIBETA detector. Minimum-$\chi^2$ fits to the measured $(E_{e^+},E_\gamma)$ energy…
The decays $\chi_{b0,2}\to\psi\psi$ and $\chi_{b0,2}\to\psi\psi\to2(\mu^+\mu^-)$ are considered. It is shown that with the help of $\psi$-meson angular distributions and the distributions by final muon kinematical variables it is possible…
Using 14 million $\psi(2S)$ events collected with the Beijing Spectrometer (BESII) at the Beijing Electron-Positron Collider, the branching fractions of $\psi(2S)$ decays to $p \bar{n} \pi^-$ and $\bar{p} n \pi^+$ and the branching…
Motivated by the recent LHCb measurements of the ratios between the branching ratios (BRs), $R_{\chi_{c2}/J/\psi} \equiv {\rm BR}(B_c^+ \to \chi_{c2} \pi^+)/{\rm BR}(B_c^+ \to J/\psi \pi^+)$ and $R_{\chi_{c1}/\chi_{c2}} \equiv {\rm…
Factorization based on the soft-collinear effective theory (SCET) can be used to reduce the number of hadronic parameters in an isospin analysis of B-> pi pi decays by one. This gives a theoretically precise method for determining the CP…
The degeneracy of chiral partners is an ideal signal for measuring the restoration of the spontaneously broken chiral symmetry in QCD. In this work, we investigate the observability of the $\phi$ - $f_1(1420)$ degeneracy in the J-PARC E16…
The decays $\rho^0\to 2\pi^+2\pi^-$ and $\rho^0\to 2\pi^0\pi^+\pi^-$ are studied using various effective Lagrangians for $\pi$ and $\rho$ (and in some cases $a_1$) mesons, all of which respect the approximate chiral symmetry of the strong…
It is shown that the existing data on two-body B decays, some of them only upper limits, are precise enough to perform an isospin analysis to extract the phase shifts due to final state interaction. Unlike charm decays, no significant final…
We construct an effective non-relativistic quantum field theory that describes bound states of pi+ pi- pairs and their hadronic decays. We then derive a general expression for the lifetime of the ground state at next-to-leading order in…
Decay channels with attractive branching ratios, or interesting physics, are recovered by substituting missing particles (nu, pi0, etc) with combined geometric and kinematic constraints. The Sliding Vertex method is shown in this part-I,…
We consider the $X(3872)$ resonance as a $J^{PC}=1^{++}$ $D\bar D^*$ hadronic molecule. According to heavy quark spin symmetry, there will exist a partner with quantum numbers $2^{++}$, $X_{2}$, which would be a $D^*\bar D^*$ loosely bound…
By analyzing a data set of 2.92 fb$^{-1}$ of $e^+e^-$ collision data taken at $\sqrt s= 3.773~\rm GeV$ and 106.41$\times 10^{6}$ $\psi(3686)$ decays taken at $\sqrt s= 3.686~\rm GeV$ with the BESIII detector at the BEPCII collider, we…