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Dynamical origin and the pole structure of X(3872).
1Gesellschaft fur Schwerionenforschung (GSI), Planck Strasse 1, 64291 Darmstadt, Germany. danilkin@itep.ru
Physical Review Letters
|September 28, 2010
Summary
This study applies channel coupling to charmonium-DD* states, explaining experimental observations like the Z(3930) resonance. The findings clarify the behavior of coupled charmonium states near the DD* threshold.
Area of Science:
- Nuclear Physics
- Particle Physics
- Quantum Chromodynamics
Background:
- Coupled charmonium states and their decay channels are crucial for understanding particle interactions.
- Experimental data shows structures near the DD* threshold that require theoretical explanation.
Purpose of the Study:
- To investigate the dynamical mechanism of channel coupling in charmonium-DD* systems.
- To explain the observed DD* production cross section and resonance structures.
Main Methods:
- Application of the dynamical mechanism of channel coupling.
- Pole analysis of coupled charmonium-DD* states with JPC=1++.
- Calculation of the DD* production cross section.
Main Results:
- The model qualitatively agrees with experimental DD* production cross sections.
- A Breit-Wigner resonance, shifted by channel coupling, explains the peak at the D0D0* threshold.
- The analysis associates a specific charmonium state (23P1) with the observed Z(3930) resonance.
Conclusions:
- Channel coupling provides a successful dynamical mechanism for describing charmonium-DD* interactions.
- The study clarifies the origin of the Z(3930) resonance and the behavior of other charmonium states.
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