Related papers: Further study of double charmonium production in e…
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…
We report the first observation of a new charmonium state at a mass of $(3.943 \pm 0.006 \pm 0.006) {GeV}/c^2$. This state, called X(3940), is observed in the process $e^+ e^- \to J/\psi X(3940)$ in the spectrum of masses recoiling against…
We review the charmonium production in $e^+e^-$ annihilation at $\sqrt{s}=10.6GeV$. NRQCD predictions for the $J/\psi$ production are compared with the recent measurements by BaBar and Belle. A NRQCD calculation for the $D$-wave charmonium…
We review the current theoretical situation with regard to the anomalously large cross section for exclusive J/psi + eta_c production in e^+ e^- annihilation, as measured by BELLE Collaboration.
We measure the cross section of $e^+e^-\rightarrow\eta_c J/\psi$ at the $\Upsilon(nS) (n=1$ -- $5)$ on-resonance and 10.52 GeV off-resonance energy points using the full data sample collected by the Belle detector with an integrated…
Belle and BaBar experiments at the KEKB and PEP-II B-factories provide also an excellent environment for spectroscopy studies. In this report we present recent results in the field of charmonium spectroscopy, focusing on new charmonium-like…
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…
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…
Recent measurements of the Belle Collaboration of the exclusive production of two charmonia in the $e^+e^-$ annihilation differ substantially from theoretical predictions. Recently it was suggested that a significant part of this…
We present a study of the X(3940) state in the process e+e- -> J/psi D* Dbar. The X(3940) mass and width are measured to be (3942 +7 -6 +- 6)MeV/c^2 and Gamma=(37 + 26 - 15 +- 8 MeV. In the process e+e- -> J/psi D* D*bar we have observed…
The recent results on charmonium and charmoniumlike states from Belle experiment are reviewed. We summarise searches in $B$ decays for possible $X$-like states in final states containing $\eta_c$. The new measurement of…
We review the current state of experimental knowledge on double ccbar production in e+e- annihilation. The large cross-sections (O(20 fb)) for e+e- -> gamma* -> psi(') ccbar_{res} processes have been confirmed by detailed tests and…
Using a data sample of 101.8 fb collected by the Belle detector at the KEKB asymmetric energy e+ e- collider, we confirm our published observation of e+ e- -> J/psi eta_c and find no evidence for the process e+ e- -> J/psi J/psi. The latter…
We report BELLE measurements of the exclusive cross sections for the processes e+e-->DD*, e+e-->DD, e+e-->DDpi, the first observation of psi(4415)-> DD*2(2460)bar decay and new state, Y(4660), using ISR. In addition, another cluster of…
Inspired by the recent observation of $e^+e^-\to \omega X(3872)$ by the BESIII Collaboration, in this work we study the production of the charmonium $\chi_{cJ}(2P)$ by $e^+e^-$ annihilation. We find that the $e^+e^-\to\omega\chi_{c0}(2P)$…
We calculate the D-wave charmonium production in $e^+e^-$ annihilation at BELLE and BABAR at $\sqrt{s}=10.6$ GeV using the nonrelativistic QCD factorization formalism, including color singlet and color octet contributions. We analyze the…
We perform a full amplitude analysis of the process $e^+ e^- \rightarrow J/\psi D \bar{D}$, where $D$ refers to either $D^0$ or $D^+$. A new charmoniumlike state $X^*(3860)$ that decays to $D \bar{D}$ is observed with a significance of…
The cross section for $e^+ e^- \to \pi^+ \pi^- J/\psi$ between 3.8 GeV and 5.5 GeV is measured with a 967 fb$^{-1}$ data sample collected by the Belle detector at or near the $\Upsilon(nS)$ ($n = 1,\ 2,\ ...,\ 5$) resonances. The Y(4260)…
We review recent measurements of pure neutral final state production, gamma gamma to pi0 pi0 and eta pi0, and observations of new charmoniumlike resonances, X(3915) and X(4350), in the two-photon processes at the Belle experiment.
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…