On the structure of the X(1835) baryonium

Abstract

The measurement by the BES collaboration of J/psi -> gamma p pbar decays indicates an enhancement at the p-pbar threshold. In another experiment BES finds a peak in the invariant mass of pi-mesons produced in the possibly related decay J/psi -> gamma pi+ pi- eta'. Using a semi-phenomenological potential model which describes all the N-Nbar scattering data, we show that the explanation of both effects may be given by a broad quasi-bound state in the spin and isospin singlet S wave. The structure of the observed peak is due to an interference of this quasi-bound state with a background amplitude and depends on the annihilation mechanism.

7 pages, 7 figures, this version corresponds to the published paper in Phys. Rev. C: minor corrections done and in section 5 suggestions of experiments to confirm the link of the X(1835) to the antiproton-proton system

References in corpus (3)

• Paris nucleon-antinucleon potential constrained by recent antiprotonic-atom data and antineutron-proton total cross sections
• ppbar enhancement in B and J/Psi decay
• Nuclear surface studies with antiprotonic atom X-rays

Cited by in corpus (28)

• Confirmation of the X(1835) and observation of the resonances X(2120) and X(2370) in J/psi->gamma pi^+pi^-eta'
• Charmed Baryonium
• Categorizing resonances X(1835), X(2120) and X(2370) in the pseudoscalar meson family
• Antinucleon-nucleon interaction at next-to-next-to-next-to-leading order in chiral effective field theory
• Observation of an anomalous line shape of the ${\eta }^{\prime }{\pi }^{+}{\pi }^{-}$ mass spectrum near the $p\bar{p}$ mass threshold in $J/\psi \to \gamma {\eta }^{\prime }{\pi }^{+}{\pi }^{-}$
• Observation and Spin-Parity Determination of the $X(1835)$ in $J/\psi \to \gamma K_S^0{K}_S^0\eta$
• On the near-threshold $\bar{p}p$ invariant mass spectrum measured in $J/\psi$ and ${\psi }^{\prime }$ decays
• Study of resonant structure around 1.8 GeV/$c^2$ and $\eta (1405)$ in $J/\psi \to \omega \eta {\pi }^{+}{\pi }^{-}$
• $X(1835)$ and the New Resonances $X(2120)$ and $X(2370)$ Observed by the BES Collaboration
• Observation of a structure at 1.84 GeV/c${}^2$ in the $3({\pi }^{+}{\pi }^{-})$ mass spectrum in $J/\psi \to \gamma 3({\pi }^{+}{\pi }^{-})$ decays
• Couplings between the $\rho$ and $D$- and $D^{\ast }$-mesons
• Observation of the Anomalous Shape of $X(1840)$ in $J/\psi \to \gamma 3({\pi }^{+}{\pi }^{-})$ Indicating a Second Resonance Near $p\bar{p}$ Threshold
• Interaction of real and virtual $p\bar{p}$ pairs in $J/\psi \to p\bar{p}\gamma (\rho ,\omega )$ decays
• $J/\psi \to \gamma {\eta }^{\prime }{\pi }^{+}{\pi }^{-}$ and the structure observed around the $\bar{p}p$ threshold
• Analysis of the X(1835) and related baryonium states with Bethe-Salpeter equation
• Structure around $p\bar{p}$ threshold in $J/\psi$ radiative decays
• Extraction of baryonia from the lightest anti-protonic atoms
• Measurement of the branching fraction of $J/\psi \to \omega {\eta }^{\prime }{\pi }^{+}{\pi }^{-}$ and search for $J/\psi \to \omega X(1835),X(1835)\to {\eta }^{\prime }{\pi }^{+}{\pi }^{-}$ decay
• The proton-antiproton mass threshold structure in psi(3686) radiative decay revisited
• Reexamination of antinucleon-nucleon interactions in covariant chiral effective field theory
• Looking for bound states and resonances in the ${\eta }^{\prime }K\bar{K}$ system
• Search for the process $e^{+}{e}^{-}\to J/\psi +X(1835)$ at $\sqrt{s}\approx 10.6$GeV
• Spin dependence of the antinucleon-nucleon interaction
• Coupled-channel analysis of the near-threshold $e^{+}{e}^{-}\to N\bar{N}$ cross sections
• Analysis of the $X(1835)$ as a baryonium state with Bethe-Salpeter equation
• Decay Widths of X(1835) as Nucleon-Antinucleon Bound State
• Baryons and baryoniums in the perspective of QCD sum rules
• Search for baryonium and the physics at FAIR