相关论文: Higher-order multipole amplitudes in charmonium ra…

In this article, we study the radiative decays among the charmonium states with the heavy quark effective theory, and make predictions for the ratios among the radiative decay widths of an special multiplet to another multiplet. The…

In this work, we calculate the nonrelativistic asymptotic behavior of the amplitudes of $q\overline{q}\rightarrow 2g \rightarrow q\overline{q}$ in the leading order of $\alpha_s$ (LO-$\alpha_s$) with $q\overline{q}$ in the $^3P_J$ channels.…

We reconstruct the charmonium mesons J/psi, psi(2S) and chi_C1 using a sample of 8.46 x 10^6 B-anti-B events collected by the BABAR detector operating at e^+e^- center of mass energies near the Y(4S) resonance. By measuring rates relative…

The determination of non-spherical angular momentum amplitudes in nucleons at long ranges (low Q^{2}), was accomplished through the $p(\vec{e},e'p)\pi^0$ reaction in the Delta region at $Q^2=0.060$, 0.127, and 0.200 (GeV/c)^2 at the Mainz…

The higher order multipoles above the electric quadrupole are commonly neglected in metamaterial homogenization. We show that they nevertheless can be significant when second order spatial dispersive effects, such as the magnetic response,…

Numerous accidental near-degeneracies exist between the $2\nu_2$ and $\nu_4$ rotation-vibration energy levels of ammonia. Transitions between these two states possess significantly enhanced sensitivity to a possible variation of the…

Very recently, the LHCb Collaboration reported the observation of several enhancements in the invariant mass spectrum of a $J/\psi$ pair between 6.2 and 7.4 GeV. In this work, we propose the dynamical mechanism to mimic the experimental…

In this talk, we present the recent results on charmonium decays from the BES experiment at the BEPC collider. The analyses are based on a 14 million psi(2S) events data sample. We report results on leptonic decays, hadronic decays, and…

Electronic structure of HCl+ and HBr+ molecular ions is calculated using the symmetry-adapted-cluster configuration interaction (SAC-CI) method. In this paper, we analyse dipole moments (DM) for a series of low-lying six 2Pi-states and…

Using a data sample of $\Upsilon(2S)$ events collected with the CLEO II detector at the Cornell Electron Storage Ring, we have investigated the hadronic transitions between the $\Upsilon(2S)$ and the $\Upsilon(1S)$. The charged dipion…

Charmonium states are expected to be considerably suppressed in the case of quark-gluon plasma formation in high-energy heavy-ion collisions. However, a robust identification of suppression patterns as signatures of a deconfined QCD medium…

In this work, we study the exclusive decay of $\Upsilon$ into $J/\psi$ in association with $\eta_c$ ($\chi_{c0,1,2}$). The decay widths for different helicity configurations are evaluated up to QCD next-to-leading order within the…

We study the charmonium suppression in different evolutions of quark gluon plasma (QGP) based on the transport model. In the colliding energies of Large Hadron Collider, charmonium final yields are dominated by the recombination of charm…

We performed the multipole decomposition analysis (MDA) for the ${}^{208}{\rm Pb}(p,n)$ data in order to obtain the spin-dipole (SD) strengths separated into each $\Delta J^{\pi}$ contribution $dB({\rm SD}_{\Delta J^{\pi}};\omega)/d\omega$.…

In the framework of the heavy baryon chiral perturbation theory (HBChPT), we calculate the radiative decay amplitudes of the singly heavy baryons up to the next-to-next-to-leading order (NNLO). In the numerical analysis, we adopt the heavy…

We report the measurements of the prompt and non-prompt J/{\psi} and {\psi}(2S) nuclear modification factors (RAA) using pp and PbPb data and the RpPb using pPb data collected by CMS at the LHC. All measurements were performed via the…

We present new results for the suppression of high transverse momentum charmonium [$J/\psi, \psi(2S)$] and bottomonium [$\Upsilon(1S),\Upsilon(2S),\Upsilon(3S)$] states in Pb+Pb collisions at the Large Hadron Collider. Our theoretical…

Using a sample of 158 million $\Upsilon(2S)$ events collected with the Belle detector, we search for the first time for double charmonium decays of the $P$-wave spin-triplet bottomonium states ($\Upsilon(2S) \to \gamma \chi_{bJ}$,…

We compute the O(alpha_s^2) correction to the decay rate eta_c --> gamma gamma and discuss its implications for precision quarkonium physics. We study the suitability of the ratio Gamma(J/psi --> e+e-)/Gamma(eta_c --> gamma gamma), in which…

We discuss the degree of anharmonicity of dipole plasmon resonances in metal clusters. We employ the time-dependent variational principle and show that the relative shift of the second phonon scales as $N^{-4/3}$ in energy, $N$ being the…