相关论文: Exclusive Double Charmonium Production from $\Upsi…
The measurement of the branching fraction of a heavy quarkonium decaying into light hadronic final state at $e^+e^-$ colliders is revisited. In $e^+e^-$ annihilation experiments, background contributions from the continuum amplitude and its…
We present a model-independent description of the exclusive rare decays B-> K* e+e- in the low recoil region (large lepton invariant mass q^2 ~ m_b^2). In this region the long-distance effects from quark loops can be computed with the help…
The production cross sections of $J/\psi~\eta_b$, $\Upsilon\;\eta_c$ pairs in a single boson $e^+e^-$ annihilation have been studied in a wide range of energies, which will be achieved at future $e^+e^-$ colliders. The main color singlet…
The prospect of experimental verification of the large extra dimension scenario in rare decays is discussed. The case of J/\Psi and \Upsilon to photon + missing energy is calculated in detail, and it is shown that the limit on the…
We report the observation of prompt J/psi via double ccbar production from the e+e- continuum. In this process one ccbar pair fragments into a J/psi meson while the remaining pair either produces a bound charmonium state or fragments into…
The QCD mechanisms underlying the exclusive strong decays and hadronic production amplitudes of charmonium remain poorly understood, despite decades of study and an increasingly detaled body of experimental information. One set of hadronic…
Using a sample of 102 million $\Upsilon(1S)$ events collected with the Belle detector, we report on the first search for charge-parity-even charmonium and charmonium-like states in $\Upsilon(1S)$ radiative decays. No significant $\chi_{cJ}$…
We make a comparative and comprehensive study on the charmonium exclusive productions at the $e^+e^-$ collider with the collision energy either round the $Z^0$-boson mass for a super $Z$ factory or equals to 10.6 GeV for the $B$ factories…
The production of a quarkonium -- pair in exclusive and diffractive processes in $pp$ collisions at the LHC and FCC energies is investigated. We consider the $J/\Psi J/\Psi$ and $\Upsilon \Upsilon$ production in these processes and present…
We study the baryonic charmonium decays of $B$ mesons, $B^+ \to \eta_c K^+$ and $B^+ \to J/\psi K^+$, where $\eta_c$ and $J/\psi$ subsequently decay into a $p\bar p$ or $\Lambda\bar\Lambda$ pair. The charmonium produced in the above $B$…
We report the observation of a narrow charmonium-like state produced in the exclusive decay process B+ -> K+ pi+pi- J/psi. This state, which decays into pi+pi- J/psi, has a mass of 3872.0+-0.6(stat)+-0.5(syst) MeV, a value that is very near…
We investigate in detail the role of heavy meson loops in the transition from $J^{PC}=1^{--}$ sources to candidates for QCD "exotics", such as $Z_c(3900)$, $Z_b(10610)$ and $Z_b'(10650)$. We demonstrate that, if a vector state strongly…
Using data taken with the CLEO II detector at the Cornell Electron Storage Ring, we have determined the ratio of branching fractions: $R_{\gamma} \equiv \Gamma(\Upsilon(1S) \rightarrow \gamma gg)/\Gamma(\Upsilon(1S) \rightarrow ggg) = (2.75…
Recent results in studies of bottomonium especially relevant to charmonium are reviewed. This report covers dipion transition matrix elements, $\eta$ production in $\Upsilon$ transitions, $\Upsilon$ decays to invisible particles, a search…
The direct production rate of $\psi$ in the $\Upsilon$ decay is shown to be dominated by the process $ \Upsilon \to ggg^*$ followed by $g^* \to \psi$ via the color-octet mechanism proposed recently to explain the anomalous prompt charmonium…
We report results of a search for the invisible decay of the Upsilon(1S) via the Upsilon(3S)->pi+pi-Upsilon(1S) transition using a data sample of 2.9 fb^{-1} at the Upsilon(3S) resonance. The data were collected with the Belle detector at…
Using a sample of 232 x 10^6 Upsilon(4S)--> B B-bar events collected with the BABAR detector at the PEP-II B-factory we study the decay B- --> [K+ pi-]_D K*- where the K+ pi- is either from a Cabibbo-favored D0-bar decay or…
In this paper, we study the production of charmonium pentaquark $c \bar c q q q$ from bottom baryon and B-meson decays under the flavor SU(3) symmetry. Decay amplitudes for various processes are parametrized in terms of the SU(3)…
We calculate the decay rate of bottomonium to two-charm quark jets $\Upsilon \to c \bar c$ at the tree level and one-loop level including color-singlet and color-octet $b \bar b$ annihilations. We find that the short distance coefficient of…
The inclusive production of charmonium mesons in B meson decay has been studied in a 20.3 fb$^{-1}$ data set collected by the BaBar experiment operating at the $\Upsilon(4S)$ resonance. Branching fractions have been measured for the…