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Published on: November 15, 2013
Tetraquark mesons in large-N quantum chromodynamics.
1Department of Physics, Theory Group, University of Texas Austin, Texas 78712, USA. weinberg@physics.utexas.edu
Physical Review Letters
|July 16, 2013
Summary
Exotic mesons, or tetraquarks, are permissible in quantum chromodynamics with many colors (N). Certain tetraquarks are long-lived, with decay rates inversely proportional to N.
Area of Science:
- Particle Physics
- Quantum Chromodynamics
- Exotic Hadrons
Background:
- Quantum chromodynamics (QCD) describes the strong force binding quarks and gluons.
- Exotic mesons, such as tetraquarks (two quarks and two antiquarks), are theoretical constructs.
- Previous assumptions suggested tetraquarks might be unstable or forbidden in certain QCD regimes.
Purpose of the Study:
- To investigate the viability of exotic mesons (tetraquarks) in quantum chromodynamics with a large number of colors (N).
- To determine the stability and decay characteristics of specific tetraquark configurations.
Main Methods:
- Theoretical analysis within the framework of quantum chromodynamics.
- Examination of quark-antiquark-antiquark-antiquark (qqqq) bound states.
- Calculation of decay rates as a function of the number of colors (N).
Main Results:
- Exotic mesons (tetraquarks) are not ruled out in quantum chromodynamics with a large N.
- A specific class of tetraquarks exhibits long-lived properties.
- The decay rates for these long-lived tetraquarks are found to be proportional to 1/N.
Conclusions:
- Tetraquarks can exist within the theoretical framework of quantum chromodynamics for large N.
- The stability of certain tetraquarks is enhanced in multi-color QCD.
- The 1/N scaling of decay rates provides a mechanism for their long lifetimes.
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