Vacuum phenomenology of the chiral partner of the nucleon in a linear sigma model with vector mesons

Journal Article · Thu Jul 01 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.82.014004· OSTI ID:21410026

Gallas, Susanna; Giacosa, Francesco ^[1]; Rischke, Dirk H ^[1]

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1. Institute for Theoretical Physics, Johann Wolfgang Goethe University, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main (Germany)

We investigate a linear sigma model with global chiral U(2){sub R}xU(2){sub L} symmetry. The mesonic degrees of freedom are the standard scalar and pseudoscalar mesons and the vector and axial-vector mesons. The baryonic degrees of freedom are the nucleon, N, and its chiral partner, N*, which is usually identified with N(1535). The chiral partner is incorporated in the so-called mirror assignment, where the nucleon mass is not solely generated by the chiral condensate but also by a chirally invariant mass term, m{sub 0}. The presence of (axial-) vector fields modifies the expressions for the axial-coupling constants of the nucleon, g{sub A}{sup N}, and its partner, g{sub A}{sup N*}. Using experimental data for the decays N*{yields}N{pi} and a{sub 1{yields}{pi}{gamma}}, as well as lattice results for g{sub A}{sup N}* we infer that in our model m{sub 0{approx}}500 MeV, i.e., an appreciable amount of the nucleon mass originates from sources other than the chiral condensate. We test our model by evaluating the decay N*{yields}N{eta} and the s-wave nucleon-pion scattering lengths a{sub 0}{sup ({+-})}.

• OSTI ID: 21410026
• Journal Information: Physical Review. D, Particles Fields, Vol. 82, Issue 1; Other Information: DOI: 10.1103/PhysRevD.82.014004; (c) 2010 The American Physical Society; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AXIAL VECTOR MESONS
CHIRALITY
CONDENSATES
COUPLING CONSTANTS
DEGREES OF FREEDOM
MASS
MEV RANGE 100-1000
N-1535 BARYONS
NUCLEONS
PARTICLE DECAY
PION-NUCLEON INTERACTIONS
PSEUDOSCALAR MESONS
S WAVES
SIGMA MODEL
SYMMETRY
U-2 GROUPS
VECTOR FIELDS
VECTOR MESONS
BARYONS
BOSON-EXCHANGE MODELS
BOSONS
DECAY
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
HADRON-HADRON INTERACTIONS
HADRONS
INTERACTIONS
LIE GROUPS
MATHEMATICAL MODELS
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
MESONS
MEV RANGE
N BARYONS
N*BARYONS
PARTIAL WAVES
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PROPERTIES
PERIPHERAL MODELS
SYMMETRY GROUPS
U GROUPS