相关论文: Double heavy-quarkonium production from electron-p…
In this work we study the process $e^{+}+e^{-}\longrightarrow J/\Psi+\eta_{c} $ at energy $\sqrt{s}= 10.6 GeV$ observed recently at B-factories whose measurements were made by Babar and Belle groups. We calculate the cross section for this…
We calculate the double charmonium production cross section within the framework of $4\times 4$ Bethe-Salpeter Equation in the electron-positron annihilation, at center of mass energy $\sqrt{s}= 10.6$GeV, that proceeds through the exchange…
We study the processes, $e^- e^+ \rightarrow \gamma^* \gamma^* \rightarrow J/\psi +J/\psi$, and $e^- e^+ \rightarrow \gamma^* \gamma^* \rightarrow \eta_c+ \eta_c$ at $\sqrt{s}=10.6$ GeV in the framework of $4\times 4$ Bethe-Salpeter…
In this paper we give estimates for the proton--proton cross sections into pairs of quarkonium states $J/\psi$, $\psi(2S)$, $\Upsilon(1S)$ and $\Upsilon(2S)$ at the scheduled AFTER@LHC energy of $115$GeV. The estimates are based on the…
The processes $e^{+}e^{-} \to \Delta^{++}\bar{\Delta}^{--}$ and $e^{+}e^{-}\to \Delta^{++} \bar{p} \pi^{-} + c.c.$ are studied for the first time with $179~{\rm pb}^{-1}$ of $e^{+}e^{-}$ annihilation data collected with the BESIII detector…
Using the nonrelativistic QCD(NRQCD) factorization formalism, we calculate the color-singlet cross sections for exclusive production processes ${e^++e^-\to J/\psi+\eta_c}$~ and ~$e^++e^-\to J/\psi + \chi_{cJ}$~$(J=0,1,2)$ at the…
The cross-section for the production of $b{\bar b} c{\bar c}$ quarks in $e^+e^-$ annihilation, that proves to be at a level of $\sigma (e^+e^- \rightarrow b{\bar b} c{\bar c})/ \sigma (e^+e^- \rightarrow b{\bar b}) \sim 10^{-2}$ for ${\sqrt…
We make a detailed study on the typical production channel of double charmoniums, $e^+e^-\to J/\psi+\eta_c$, at the center-of-mass collision energy $\sqrt{s}=10.58$ GeV. The key component of the process is the form factor $F_{\rm VP}(q^2)$,…
We study the production of $J/\psi+c\bar{c}$ in $e^+e^-$ annihilation through two virtual photons. The cross section is estimated to be 23 fb at $\sqrt{s}=10.6$ GeV, which is smaller by a factor of six than the calculated cross section for…
In the framework of quark-hadron duality, the cross section values of charmonium and doubly charmed baryon production in $e^+e^-$-annihilations have been estimated at interaction energy $\sqrt{s}=10.6$ GeV. It has been shown that the…
BELLE Collaboration data for $J/\psi$ inclusive production in the processes $e^+e^-\to J/\psi+gg$ and $e^+e^-\to J/\psi +c\bar c$ have been discussed. These data have been compared with the predictions of two pQCD methods: the former method…
As a test of the color-singlet mechanism of the nonrelativistic QCD (NRQCD) factorization approach, we consider the exclusive two-quarkonium productions in electron-positron annihilation e+ e- -> eta_c + gamma and e+ e- -> J/psi + J/psi at…
Within the NRQCD framework, we calculate the exclusive production of double heavy quarkonium(double charmonium and double bottomonium) at future super $Z$ factory and at the CEPC/FCC-ee. The color-octet(CO) channels in the…
Recently, several surprising experimental observations in the production of heavy quarkonium have been reported. In $e^+e^-$ annihilation at $\sqrt{s}=10.6$ GeV, Belle Collaboration finds that $J/\psi$ mesons are predominantly produced in…
We predict the rate for exclusive double-charmonium production in electron-positron annihilation $e^+ e^- \to J/\psi+\eta_c$ using perturbative quantum chromodynamics and the NRQCD framework for hard, heavy-quarkonium exclusive processes.…
The double J/psi production in p\bar{p} collision is revisited. It is found that the J/\psi pair production rate at leading order with p_T > 4 GeV in conventional scheme is larger than the rate derived from color-octet mechanism by a factor…
We report the first observation of the processes $e^+e^-\to\Upsilon(\rm 1S,2S)\eta$ at $\sqrt{s}=10.866$~GeV with a $10.2\sigma$ and $16.5\sigma$ significance respectively. The measured Born cross sections are $\sigma(e^+e^- \to…
Using a 478 pb$^{-1}$ data sample collected with the BESIII detector operating at the BEPCII storage ring at a center-of-mass energy of $\sqrt{s}=4.009$ GeV, the production of $e^{+}e^{-}\to \eta J\psi$ is observed for the first time with a…
The exclusive production of double excited quarkonium is comprehensive studied, i.e., the production of double excitedcharmonium, double excited bottomonium, and double excited $Bc$-mesons via $e^+e^-\to \gamma^*/Z^0…
We present a new analysis of double charmonium production in e^+ e^- annihilation. The observation of the processes e^+ e^- -> J/psi eta_c, J/psi chi_c0, and J/psi eta_c(2S) is confirmed using a dataset more than three times larger than…