Strong and electromagnetic decays ofX(1835) as a baryonium state

Abstract

With the assumption that the recently observed X(1835) is a baryonium state we have studied the strong decays of X(1835) → η (′) π + π − , η (′) π 0 π 0 and the electromagnetic decay of X(1835) → 2γ in the framework of effective Lagrangian formalism. In the present investigation we have included the contributions from the iso-singlet light scalar resonances but we have not included the isospin violating effect. Our result for the strong decay of− is smaller than the observed data. The decay width for the radiative decay of X(1835) → 2γ is consistent with the assumption that it decays through the glueball. In addition, the width for the strong decay of X(1835) → ηπ + π − is larger than that of the strong decay of X(1835) → η ′ π + π − due to the large phase space and coupling constant g NN η . From our investigation, it is not possible to interpret X(1835) as a baryonium.

Status of X(1835) and pp¯ Interaction from Chiral Symmetry

“…Figure 2). Correspondingly, g X pp = 2.37 ∼ 2.55 was used [62], and this value is consistent with the one in Ref. [60].…”

“…In Ref. [62], some more quantitative calculations were performed, which rely on the constructed effective Lagragian, and the coupling constants therein are fixed by other experimental information from J/ψ decay or the NN scattering observable. Its results show that:…”

Categorizing resonancesX(1835),X(2120), andXYu1, Sun2, Liu3 et al. 2011Phys. Rev. D681620View full textAdd to dashboardCite

“…However, the calculations of the strong and electromagnetic decays of Xð1835Þ under the baryonium assumption obtained a rather small width for Xð1835Þ ! 0 þ À [21].…”

Decay widths of theX(1835)as anN¯Nbound state

“…Among the interpretations are the N N bound state [6][7][8][9][10][11][12][13][14][15][16], the baryonium with sizable gluon content [17], the pseudoscalar glueball [18][19][20][21], the radial excitation of the η ′ [22][23][24][25], and the η c -glueball mixture [26,27]. The N N bound state interpretation has been the most natural one since the X(1835) resonance is a prime candidate for the source of the pp invariant mass enhancement in J/ψ → γpp reaction.…”