Charmonium options for theX(3872)

Abstract

In this paper we consider all possible 1D and 2 P cc assignments for the recently discovered X(3872). Taking the experimental mass as input, we give numerical results for the E1 radiative widths as well as the three principal types of strong decays; open-charm, cc annihilation and closed-charm hadronic transitions. We find that many assignments may be immediately eliminated due to the small observed total width. The remaining viable cc assignments are 1 . A search for the mode J/ 0 0 can establish the C parity of the X(3872), which will eliminate many of these possibilities. Radiative transitions can then be used to test the remaining assignments, as they populate characteristic final states. The 1 3 D 2 and 1 1 D 2 states are predicted to have large ͑ca. 50%͒ radiative branching fractions to c1 ␥ and h c ␥, respectively. We predict that the 1 3 D 3 will also be relatively narrow and will have a significant ͑ca. 10%͒ branching fraction to c2 ␥, and should also be observable in B decay. Tests for non-cc X(3872) assignments are also discussed.

The hidden-charm pentaquark and tetraquark states

“…Quark model. There are lots of discussions on the interpretation of the X(3872) as a P-wave charmonium state [581,582,583,584,585,586,587,588,589,590,591,592,593,594,595]. But there exist two major difficulties:…”

Analysis of the Quantum NumbersJPCof theX(3872) Particle

“…The close proximity of the X(3872) particle mass to the D 0D * 0 mass threshold has raised the question whether the X(3872) particle is an exotic form of matter [3]. The determination of the quantum numbers spin J, parity P , and charge conjugation parity C is of vital importance for establishing the nature of the X(3872) particle.…”

“…PACS numbers: 14.40.Gx,12.39.Mk,13.25.Gv tempts to explain the X(3872) particle as a conventional bound quark-antiquark state have shortcomings, such as deviations from mass predictions or violation of isospin conservation [3]. The close proximity of the X(3872) particle mass to the D 0D * 0 mass threshold has raised the question whether the X(3872) particle is an exotic form of matter [3].…”

Precision Measurement of theX(3872)Mass inJ/ψπ+π−Decays

“…DOI: 10.1103/PhysRevLett.103.152001 PACS numbers: 14.40.Gx, 12.39.Mk, 13.25.Gv The discovery of the Xð3872Þ [1,2] and many additional unexpected states [3] has revived general interest in spectroscopy in the charmonium mass region. Initial attempts to explain the Xð3872Þ as a conventional bound state of a c quark and an anti-c quark have shortcomings [4] which triggered the development of unconventional explanations. Two popular models are a molecular state composed of D 0 and " D Ã0 mesons [5,6], and a four-quark state [7].…”