Related papers: Understanding the Possible Proton Antiproton Bound…

The BES collaboration has recently observed a strong enhancement close to the proton-antiproton threshold in the J/Psi decays into photon, proton and antiproton. Such a structure can be explained by a traditional nucleon-antinucleon model.…

The recent measurements by the BES Collaboration of J/psi decays into a photon and a proton-antiproton pair indicate a strong enhancement at the proton-antiproton threshold not observed in the decays into a neutral pion and a…

The recent BES Collaboration data on $\psi' \ra PV$, particularly the isospin violating mode $\psi' \ra \pi^0 \omega^0$ and finding of a finite number for $B(\psi' \ra K^{*0}\bar{K}^0)$, enable us now to deal more precisely about the…

We study the possible interpretation of the two exotic resonances $J^{PC}= 1^{-+}$ at 1400 and 1600 MeV, claimed to be observed by BNL, decaying respectively into $\eta\pi$, $\eta'\pi$, $f_{1}\pi$ and $\rho\pi$. These objects are…

The existence of nucleon-antinucleon quasi-bound state is indicated in two decay modes of the J/psi meson studied by BES. We discuss an explanation in a fairly traditional Paris-potential model of the nucleon-antinucleon interactions. A…

[abridged] Bound states of heavy quarks can serve as a laboratory for inquiry into the behaviour of the fundamental strong and electroweak interactions. This thesis examines observations of B0, B0bar, and B+- mesons produced in…

We propose that the broad $1^{--}$ resonance structure recently discovered by BES in $J/\psi\to K^{+}K^{-}\pi^{0}$ is the P-wave excitation of a diquark-antidiquark bound state. This interpretation implies that there exists a negative…

An analysis of the $J/\psi\to \eta\eta^\prime\gamma$ decay by the BESIII collaboration claims the observation of an exotic state $\eta_1(1855)$ with $I^GJ^{PC}=0^+1^{-+}$. To establish its C-parity partner $\eta^\prime_{1}(1855)$ in the…

We discuss the possibility of observing a loosely bound molecular state in a B three-body hadronic decay. In particular we use the QCD sum rule approach to study a $\eta^\prime-\pi$ molecular current. We consider an isovector-scalar $I^G…

Based on a novel method for producing antineutrons via $J/\psi$ decays, we report a study of $\bar{n}p$ inelastic scattering into final states containing kaons. The analysis uses $(10087\pm44)\times 10^6$ $J/\psi$ events collected at the…

We report a search for $B$ decays to selected final states with the $\eta_c$ meson: $B^{\pm}\to K^{\pm}\eta_c\pi^+\pi^-$, $B^{\pm}\to K^{\pm}\eta_c\omega$, $B^{\pm}\to K^{\pm}\eta_c\eta$ and $B^{\pm}\to K^{\pm}\eta_c\pi^0$. The analysis is…

We report a search for $B$ decays to selected final states with the $\eta_c$ meson: $B^{\pm}\to K^{\pm}\eta_c\pi^+\pi^-$, $B^{\pm}\to K^{\pm}\eta_c\omega$, $B^{\pm}\to K^{\pm}\eta_c\eta$ and $B^{\pm}\to K^{\pm}\eta_c\pi^0$. The analysis is…

Indications of the existence of quasi-bound states in the N-Nbar system are presented. Measurements by BES discovered a broad enhancement close to the p-pbar threshold in the S wave, isospin 0 state formed in radiative decays of J/psi.…

Angular correlations in $B^+\to X(3872) K^+$ decays, with $X(3872)\to \rho^0 J/\psi$, $\rho^0\to\pi^+\pi^-$ and $J/\psi \to\mu^+\mu^-$, are used to measure orbital angular momentum contributions and to determine the $J^{PC}$ value of the…

The measurements of the $J/\psi \rightarrow \gamma p \overline{p}$ decays by the BES Collaboration indicate an enhancement at the $p \overline{p}$ threshold which, however, is not present in the J/$\psi$ decays into $\omega p \overline{p}$…

The measurements of J/psi decays into photon, proton and antiproton show a strong enhancement at the proton-antiproton threshold not seen in the decays into neutral pion, proton and antiproton. What is the nature of this enhancement? A…

The Positronium (Ps) system, a bound state of an electron and a positron, is suitable for testing the predictions of quantum electrodynamics (QED), since its properties can be perturbatively calculated to high accuracy and, unlike the…

A search is presented for charged Higgs bosons in the H$^{\pm}$ $\to$ $\tau^{\pm}\nu_\tau$ decay mode in the hadronic final state and in final states with an electron or muon. The search is based on proton-proton collision data recorded by…

Spin polarization and entanglement are utilized by the BESIII experiment to learn more about the production and decay properties of hyperon-antihyperon pairs in a series of recent analyses of its unprecedented datasets at the $J/\psi$ and…

We investigate the sensitivity of the Electron-Ion Collider (EIC) to invisible final states in coherent exclusive electroproduction. The characteristic signal is a forward proton with reduced energy and little additional detector activity.…