Mass corrections to forbidden'' charmonium decays:. eta. sub c ,. chi. sub c 0 r arrow p p

Journal Article · Tue Dec 01 04:00:00 EST 1992 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.46.5049· OSTI ID:6949394

Anselmino, M ^[1]; Cancelliere, R ^[2]; Murgia, F ^[3]

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1. Dipartimento di Fisica Teorica, Universita di Torino and Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Via P. Giuria 1, I-10125 Torino (Italy)
2. Dipartimento di Fisica Teorica, Universita di Torino, Via P. Giuria 1, I-10125 Torino (Italy)
3. Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari, Via A. Negri 18, I-09127 Cagliari (Italy)

Some exclusive decays of charmonium states are forbidden, in the framework of perturbative QCD quark models, by the helicity-conservation rule, related to the vector coupling of gluons to (almost) massless quarks. Among them, we consider here {eta}{sub {ital c}} and {chi}{sub {ital c}0} decays into {ital p{bar p}}; after discussing possible nonperturbative corrections, we show that, assigning to the quarks a constituent rather than a current mass, one obtains nonzero values for such processes. The values found for {Gamma}({chi}{sub {ital c}0}{r arrow}{ital p{bar p}}) are almost as large as those obtained for similar, nonforbidden decays in the massless quark scheme, {chi}{sub {ital c}1,}{ital c2}{r arrow}{ital p{bar p}}; {Gamma}({eta}{sub {ital c}}{r arrow}{ital p{bar p}}), however, turns out to be much smaller than the experimental data, enhancing, once more, the peculiarity of many {eta}{sub {ital c}} decays. Mass corrections to some other allowed decays, {chi}{sub {ital c}0}{r arrow}{pi}{pi} and {chi}{sub {ital c}0} into longitudinally polarized vector mesons, are computed and shown to be relevant.

• OSTI ID: 6949394
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 46:11; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

662230 -- Quantum Chromodynamics-- (1992-)
662350* -- Decays of Mesons-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTIBARYONS
ANTIMATTER
ANTINUCLEI
ANTINUCLEONS
ANTIPARTICLES
ANTIPROTONS
BARYONS
BOSONS
CHARMONIUM
COMPOSITE MODELS
COUPLING
DECAY
ELEMENTARY PARTICLES
ENERGY-LEVEL TRANSITIONS
EXCLUSIVE INTERACTIONS
FERMIONS
FIELD THEORIES
FORBIDDEN TRANSITIONS
FUNCTIONS
GLUONS
HADRONS
HELICITY
INTERACTIONS
MATHEMATICAL MODELS
MATTER
MESONS
NUCLEI
NUCLEONS
PARTICLE DECAY
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PARTICLE PROPERTIES
PERTURBATION THEORY
POSTULATED PARTICLES
PROTONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARK MODEL
QUARKONIUM
VECTOR MESONS
WAVE FUNCTIONS