相关论文: Phenomenological study on the decay widths of $\Up…

$d^\ast(2380)$ was observed by WASA-at-COSY collaborations in the nuclear reaction recently. Its particularly narrow width may indicate the new QCD-allowed hadronic structure. To further confirm the existence of this peculiar particle in a…

The dielectron widths of $\Upsilon(nS) (n=1,...,7)$ and vector decay constants are calculated using the Relativistic String Hamiltonian with a universal interaction. For $\Upsilon(nS) (n=1,2,3)$ the dielectron widths and their ratios are…

Using CLEO data, we study the production of the anti-deuteron, d-bar, in Upsilon(nS) resonance decays and the nearby continuum. The branching ratios obtained are B^dir(Upsilon(1S) --> d-bar X) = (3.36 +- 0.23 +- 0.25) x 10^-5, B(Upsilon(1S)…

The di-electron width of an Upsilon meson is the decay rate of the Upsilon into an electron-positron pair, expressed in units of energy. We measure the di-electron width of the Upsilon(1S) meson to be 1.354 +- 0.004 +- 0.020 keV (the first…

The in-medium partial decay widths of $\Upsilon (4S) \rightarrow B\bar B$ in magnetized asymmetric nuclear matter are studied using a field theoretic model for composite hadrons with quark (and antiquark) constituents. The medium…

Attempts to reproduce theoretically the relatively small width, $\Gamma_{d^{\ast}}=80\pm 10$ MeV, of the $I(J^P)=0(3^+)$ $d^{\ast}$(2380) dibaryon resonance established by the WASA-at-COSY Collaboration are discussed. The validity of…

The decay widths of the $\ds\to d \pi^0\pi^0$ and $\ds\to d \pi^+\pi^-$ processes are explicitly calculated in terms of our chiral quark model. By using the experimental ratios of cross sections between various decay channels, the partial…

The ${\Upsilon}(nS)$ ${\to}$ $B_{c}D_{s}$, $B_{c}D_{d}$ weak decays are studied with the pQCD approach firstly. It is found that branching ratios ${\cal B}r({\Upsilon}(nS){\to}B_{c}D_{s})$ ${\sim}$ ${\cal O}(10^{-10})$ and ${\cal…

We present a study of the inclusive $D^{*\pm}$ production in the decay of $\Upsilon(1S)$ using $(98.6 \pm 0.9)\times 10^6$ $\Upsilon(2S)$ mesons collected with the BaBar detector at the $\Upsilon(2S)$ resonance. Using the decay chain…

The decay widths of four-body double-pion decays $\ds\to pn \pi^0\pi^0$, $\ds\to pn \pi^+\pi^-$, and iso-scalar parts of $\ds\to pp \pi^0\pi^-$ and $\ds\to nn \pi^+\pi^0$ are explicitly calculated with the help of the $d^*$ wave function…

The decay width and mass of the Ds1(2536)+ meson are measured via the decay channel Ds1+ -> D*+KS0 using 385 fb^-1 of data recorded with the BABAR detector in the vicinity of the Y(4S) resonance at the PEP-II asymmetric-energy…

The widths of a class of two-body $\bar{B}_s^0 $ decays induced by $b \to c \bar u d$ and $b \to c \bar u s$ transitions are determined in a model-independent way, using $SU(3)_F$ symmetry and existing information on $\bar B \to D_{(s)} P$…

An outstanding problem in the theory of nuclear fission is understanding the Hamiltonian dynamics at the scission point. Here we apply the Generator Coordinate Method to calculate decay widths for pre-scission configurations into the…

The ${\Upsilon}(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ weak decay is studied with the perturbative QCD approach firstly. It is found that (1) main contributions to branching ratio come from the longitudinal and parallel helicity amplitudes, (2)…

We report on measurements of the Upsilon(1S), Upsilon(2S) and Upsilon(3S) differential and integrated cross sections in pp(bar) collisions at sqrt(s)=1.8 TeV. The three resonances were reconstructed through the decay Upsilon-->mu(+)mu(-).…

We study the changes in the partial decay widths of excited charmonium states into $D \bar{D}$, when the D meson mass decreases in nuclear matter, taking the internal structure of the hadrons into account. Calculations within the 3P0 model…

We determine the di-electron widths of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) resonances with better than 2% precision by integrating the cross-section of e+e- -> Upsilon over the e+e- center-of-mass energy. Using e+e- energy scans…

We study the properties of charmed, nonstrange, $\rm D$ mesons produced in continuum $\rm {e^+}{e^-}$ annihilations. The $ \rm {e^+}{e^-}$ collisions were generated in the energy region of the $ \rm \Upsilon(3S)$ and $ \rm \Upsilon(4S)$…

The $\psi(3770)$ and $\Upsilon(4S)$ states predominantly decay into open-flavor meson pairs, whereas the decays of $\psi(3770) \to \mbox{\text{non}-}D\bar{D}$ and $\Upsilon(4S) \to \mbox{\text{non}-}B\bar{B}$ are rare but crucial for…

In this work, we investigate the characteristics of the spin-singlet state $\eta_b$ of the bottomonia family via the radiative decays of $\Upsilon(nS)\to \eta_b+\gamma$. The theoretical estimation of the decay widths is carried out in terms…