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Title: Doubly heavy baryons, heavy quark-diquark symmetry, and nonrelativistic QCD

Abstract

In the heavy quark limit, properties of heavy mesons and doubly heavy baryons are related by heavy quark-diquark symmetry. This problem is reanalyzed in the framework of nonrelativistic QCD (NRQCD). We introduce a novel method for deriving potential NRQCD (pNRQCD) Lagrangians for composite fields from vNRQCD, which contains quarks and antiquarks as explicit degrees of freedom and maintains manifest power counting in the velocity via a label formalism. A Hubbard-Stratonovich transformation is used to eliminate four quark interactions in vNRQCD and then quarks and antiquarks are integrated out to get effective Lagrangians for composite fields. This method is used to rederive Lagrangians for the QQ and QQ sectors of pNRQCD and give a correct derivation of the O(1/m{sub Q}) prediction for the hyperfine splitting of doubly heavy baryons.

Authors:
 [1];  [2];  [3]
  1. Department of Physics, University of Arizona, Tucson, Arizona 85721 (United States)
  2. Department of Physics, Duke University, Durham, North Carolina 27708 (United States)
  3. (United States)
Publication Date:
OSTI Identifier:
20776674
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevD.73.034502; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; B QUARKS; BAG MODEL; BARYONS; C QUARKS; DEGREES OF FREEDOM; LAGRANGIAN FIELD THEORY; LAGRANGIAN FUNCTION; MESONS; POTENTIALS; QUANTUM CHROMODYNAMICS; SYMMETRY; T QUARKS; TRANSFORMATIONS

Citation Formats

Fleming, Sean, Mehen, Thomas, and Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606. Doubly heavy baryons, heavy quark-diquark symmetry, and nonrelativistic QCD. United States: N. p., 2006. Web. doi:10.1103/PhysRevD.73.034502.
Fleming, Sean, Mehen, Thomas, & Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606. Doubly heavy baryons, heavy quark-diquark symmetry, and nonrelativistic QCD. United States. doi:10.1103/PhysRevD.73.034502.
Fleming, Sean, Mehen, Thomas, and Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606. Wed . "Doubly heavy baryons, heavy quark-diquark symmetry, and nonrelativistic QCD". United States. doi:10.1103/PhysRevD.73.034502.
@article{osti_20776674,
title = {Doubly heavy baryons, heavy quark-diquark symmetry, and nonrelativistic QCD},
author = {Fleming, Sean and Mehen, Thomas and Jefferson Laboratory, 12000 Jefferson Avenue, Newport News, Virginia 23606},
abstractNote = {In the heavy quark limit, properties of heavy mesons and doubly heavy baryons are related by heavy quark-diquark symmetry. This problem is reanalyzed in the framework of nonrelativistic QCD (NRQCD). We introduce a novel method for deriving potential NRQCD (pNRQCD) Lagrangians for composite fields from vNRQCD, which contains quarks and antiquarks as explicit degrees of freedom and maintains manifest power counting in the velocity via a label formalism. A Hubbard-Stratonovich transformation is used to eliminate four quark interactions in vNRQCD and then quarks and antiquarks are integrated out to get effective Lagrangians for composite fields. This method is used to rederive Lagrangians for the QQ and QQ sectors of pNRQCD and give a correct derivation of the O(1/m{sub Q}) prediction for the hyperfine splitting of doubly heavy baryons.},
doi = {10.1103/PhysRevD.73.034502},
journal = {Physical Review. D, Particles Fields},
number = 3,
volume = 73,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2006},
month = {Wed Feb 01 00:00:00 EST 2006}
}
  • In the heavy quark limit, properties of heavy mesons and doubly heavy baryons are related by heavy quark-diquark symmetry. This problem is reanalyzed in the framework of Non-Relativistic QCD (NRQCD). We introduce a novel method for deriving Potential NRQCD (pNRQCD) Lagrangians for composite fields from vNRQCD, which contains quarks and antiquarks as explicit degrees of freedom and maintains manifest power counting in the velocity via a label formalism. A Hubbard-Stratonovich transformation is used to eliminate four quark interactions in vNRQCD and then quarks and antiquarks are integrated out to get effective Lagrangians for composite fields. This method is used tomore » rederive Lagrangians for the Q\bar Q and QQ sectors of pNRQCD and give a correct derivation of the O(1/m_Q) prediction for the hyperfine splitting of doubly heavy baryons.« less
  • We extend the chiral Lagrangian with heavy quark-diquark symmetry to quenched and partially quenched theories. These theories are used to derive formulae for the chiral extrapolation of masses and hyperfine splittings of doubly heavy baryons in lattice QCD simulations. A quark-diquark symmetry prediction for the hyperfine splittings of heavy mesons and doubly heavy baryons is rather insensitive to chiral corrections in both quenched and partially quenched QCD. Extrapolation formulae for the doubly heavy baryon electromagnetic transition moments are also determined for the partially quenched theory.
  • We extend the chiral Lagrangian with heavy quark-diquark symmetry to quenched and partially quenched theories. These theories are used to derive formulas for the chiral extrapolation of masses and hyperfine splittings of double heavy baryons in lattice QCD simulations. A quark-diquark symmetry prediction for the hyperfine splittings of heavy mesons and doubly heavy baryons is rather insensitive to chiral corrections in both quenched and partially quenched QCD. Extrapolation formulas for the doubly heavy baryon electromagnetic transition moments are also determined for the partially quenched theory.
  • In the limit of heavy quark masses going to infinity, a symmetry is known to emerge in QCD relating properties of hadrons with two heavy quarks to analogous states with one heavy antiquark. A key question is whether the charm mass is heavy enough so that this symmetry is manifest in at least an approximate manner. The issue is crucial in attempting to understand the recent reports by the SELEX Collaboration of doubly charmed baryons. We argue on very general grounds that the charm quark mass is substantially too light for the symmetry to emerge automatically via color coulombic interactions.more » However, the symmetry could emerge approximately depending on the dynamical details of the nonperturbative physics. To treat the problem systematically, a new expansion that simultaneously incorporates NRQCD and HQET is needed.« less