Interference effects in the X(4260) signal

Abstract

We show that the long known puzzling branching ratios of open-charm decays in electron-positron annihilation can be reasonably described with a simple form factor, which strongly suppresses open channels far above threshold. Application to the electron-positron annihilation into J/psi+pion+pion data on the X(4260) enhancement recently reported by the BABAR Collaboration [arxiv:0808.1543] allows a good fit with a simple nonresonant cusp structure around the D(*)(s)+Dbar(*)(s) threshold. Moreover, we argue that a closer look at the data reveals an oscillatory pattern, which we model as an interference effect between a fast - OZI-allowed - and a slow - OZI-forbidden - J/psi+f(0)(980) mode. Other candidates for similar nonresonant enhancements are discussed.

8 pages, regular LaTeX, 4 figures

References in corpus (6)

• Measurement of e^+e^- to pi^+pi^-J/psi Cross Section via Initial State Radiation at Belle
• Evidence for a Narrow Near-Threshold Structure in the $J/\psi \varphi$ Mass Spectrum in $B^{+}\to J/\psi \varphi K^{+}$ Decays
• How Resonances can synchronise with Thresholds
• The X(4260) and possible confirmation of psi(3D), psi(5S), psi(4D), psi(6S) and psi(5D) in J/psi pi+ pi-
• The spectrum of charmonium in the Resonance-Spectrum Expansion
• New charmonium-like states

Cited by in corpus (2)

• The Y(4140), X(4260), psi(2D), psi(4S) and tentative psi(3D)
• Mass and width of the Upsilon(4S)