Three-body DD{pi} dynamics for the X(3872)

Journal Article · Sat Oct 01 00:00:00 EDT 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.84.074029· OSTI ID:21607787

Baru, V; Filin, A A; Hanhart, C; Kalashnikova, Yu S; Kudryavtsev, A E; Nefediev, A V ^[1]

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1. Institut fuer Theoretische Physik II, Ruhr-Universitaet Bochum, D-44780 Bochum, Germany, and Institute for Theoretical and Experimental Physics, B. Cheremushkinskaya 25, 117218 Moscow (Russian Federation)

We investigate the role played by the three-body DD{pi} dynamics on the near-threshold resonance X(3872) charmonium state, which is assumed to be formed by nonperturbative DD{sup *} dynamics. It is demonstrated that, as compared to the naive static-pions approximation, the imaginary parts that originate from the inclusion of dynamical pions reduce substantially the width from the DD{pi} intermediate state. In particular, for a resonance peaked at 0.5 MeV below the D{sup 0}D{sup *0} threshold, this contribution to the width is reduced by about a factor of 2, and the effect of the pion dynamics on the width grows as long as the resonance is shifted towards the D{sup 0}D{sup 0{pi}0} threshold. Although the physical width of the X is dominated by inelastic channels, our finding should still be of importance for the X line shapes in the DD{pi} channel below DD{sup *} threshold. For example, in the scattering length approximation, the imaginary part of the scattering length includes effects of all the pion dynamics and does not only stem from the D{sup *} width. Meanwhile, we find that another important quantity for the X phenomenology, the residue at the X pole, is weakly sensitive to dynamical pions. In particular, we find that the binding energy dependence of this quantity from the full calculation is close to that found from a model with pointlike DD{sup *} interactions only, consistent with earlier claims. Coupled-channel effects (inclusion of the charged DD{sup *} channel) turn out to have a moderate impact on the results.

• OSTI ID: 21607787
• Journal Information: Physical Review. D, Particles Fields, Vol. 84, Issue 7; Other Information: DOI: 10.1103/PhysRevD.84.074029; (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTI-D NEUTRAL MESONS
APPROXIMATIONS
BINDING ENERGY
CHARMONIUM
COUPLED CHANNEL THEORY
D MESONS
INTERACTIONS
INTERMEDIATE STATE
MEV RANGE 01-10
PERTURBATION THEORY
PIONS
RESONANCE
SCATTERING LENGTHS
ANTIMATTER
ANTIMESONS
ANTIPARTICLES
BOSONS
CALCULATION METHODS
CHARM PARTICLES
CHARMED MESONS
D NEUTRAL MESONS
DIMENSIONS
ELEMENTARY PARTICLES
ENERGY
ENERGY RANGE
HADRONS
LENGTH
MATTER
MESONS
MEV RANGE
PSEUDOSCALAR ANTIMESONS
PSEUDOSCALAR MESONS
QUARKONIUM