Width of exotics from QCD sum rules : Tetraquarks or molecules?

Journal Article · Wed Oct 01 04:00:00 EDT 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.076001· OSTI ID:21254346

Lee, Su Houng; Morita, Kenji ^[1]; Nielsen, Marina ^[2]

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1. Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of)
2. Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05389-970 Sao Paulo, Sao Paulo (Brazil)

We investigate the widths of the recently observed charmonium like resonances X(3872), Z(4430), and Z{sub 2}(4250) using QCD sum rules. Extending previous analyses regarding these states as diquark-antiquark states or molecules of D mesons, we introduce the Breit-Wigner function in the pole term. We find that introducing the width increases the mass at the small Borel window region. Using the operator-product expansion up to dimension 8, we find that the sum rules based on interpolating current with molecular components give a stable Borel curve from which both the masses and widths of these resonances can be well obtained. Thus the QCD sum rule approach strongly favors the molecular description of these states.

• OSTI ID: 21254346
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 7 Vol. 78; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BREIT-WIGNER FORMULA
CHARMONIUM
D MESONS
MASS
MOLECULES
OPERATOR PRODUCT EXPANSION
QUANTUM CHROMODYNAMICS
QUARK-ANTIQUARK INTERACTIONS
RESONANCE
SUM RULES