相关论文: Electroweak production of $\chi_{Q1}$ states in $e…

Direct, resonant production of the charmonium states $\chi_{c1}$ and $\chi_{c2}$ in electron-positron annihilation is investigated. Depending on details of the model, a sizeable variation of the prediction for the production cross section…

We study the direct production of the $J^{PC}=1^{++}$ charmonium state $\chi_{c1}(1P)$ in electron-positron annihilation by carrying out an energy scan around the mass of the $\chi_{c1}(1P)$. The data were collected with the BESIII detector…

Inclusive production of $\chi_{c J}$ in $e^+e^-$ annihilation is an excellent probe of the role of higher Fock states in the production of heavy quarkonia. Within the non-relativistic QCD approach, contributions from the short-distance…

The production cross sections of charmonia, charmonium-bottomonium and bottomonia 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 such as ILC…

It is shown that the molecular model for the X{3872) state contradicts the new experimental data as well as the old ones. It is suggested to study the \chi_{c1} and \chi_{b1} states in the e+e-\to\chi_{c1}/\chi_{b1} reactions.

The particle production in photon-photon ($\gamma \gamma$) interactions present in electron-ion collisions is investigated. We present calculations for the total cross sections and event rates related to the production of light mesons…

The existence of pentaquarks, namely baryonic states made up of four quarks and one antiquark, became questionable, because the candidates, i.e. the $\Theta^+$ peak, are seen in certain reactions, i.e. p+p collisions, but not in others,…

We report the first observation of $e^+e^-$ annihilations into hadronic states of positive $C$-parity, $\rho^0 \rho^0$ and $\phi\rho^0$. The angular distributions support two-virtual-photon annihilation production. We also report the…

Productions and decays of spin-singlet $S,P-$wave charmonium states, $\eta_{c}^{'}$ and $h_{c} (^{1}P_{1})$, in the $e^+ e^-$ annihilations are considered in the QCD multipole expansion with neglecting nonlocality in time coming from the…

Predictions of the nonperturbative Quark Gluon Strings model based on the 1/N-expansion in QCD and string picture of interactions for production of states containing heavy quarks are considered. Relations between fragmentation functions for…

We investigate the associated production of heavy quarkonia, with angular-momentum quantum numbers ^{2S+1}L_J = ^1S_0, ^3S_1, ^1P_1, ^3P_J (J = 0, 1, 2), and photons, Z bosons, and W bosons in photon-photon, photon-hadron, and hadron-hadron…

We suggest searching for excited charmonium states in $e^+e^-$ annihilation via double charmonium production at $\sqrt{s}=10.6$ GeV with $B$ factories, based on a more complete leading order calculation including both QCD and QED…

The exchange of gluons between heavy quarks produced in $e^+e^-$ interactions results in an enhancement of their production near threshold. We study QCD threshold effects in $\gamma\gamma$ collisions. The results are relevant to heavy quark…

We study the production processes e^+ e^- -> chi^+_i chi^-_j, i,j=1,2, and e^+ e^- -> chi^0_m chi^0_n, m,n=1,...,4, working out the advantages of polarizing both beams. For e^+ e^- -> chi^+_1 chi^-_1 with chi^-_1 -> chi^0_1 e^- nu and e^+…

Within the framework of the non-relativistic QCD, we present a detailed discussion on the heavy quarkonium production at the leading order in $\alpha_s$ at a $e^+ e^-$ collider with the collision energy around the $Z^0$ peak. Quarkonia are…

The cross sections for the hadroproduction of the Chi1 and Chi2 states of charmonium in proton-silicon collisions at sqrt{s}=38.8 GeV have been measured in Fermilab fixed target Experiment 771. The Chi states were observed via their…

The production of the \chi_{c2} charmonium state in two-photon collisions has been measured with the Belle detector at the KEKB e^+e^- collider. A clear signal for \chi_{c2} --> \gamma J/\psi, J/\psi --> l^+l^- is observed in a 32.6fb^{-1}…

The collisions of high energy photons produced at an electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions, and extensions of the Standard Model. The luminosity and energy of the colliding…

Up to now, the $N^*$ production from $e^+e^-$ annihilations has been studied only around charmonium region. Charmonium decays to $N^*$s are analogous to (time-like) EM form factors in that the charm quark annihilation provides a nearly…

Recent measurements by the Belle Collaboration of the exclusive production of two charmonia in e^+ e^- annihilation differ substantially from theoretical predictions. We suggest that a significant part of the discrepancy can be explained by…