Radiative decay of vector quarkonium: Constraints on glueballs and light gluinos

Journal Article · Thu Sep 01 04:00:00 EDT 1994 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.50.3268· OSTI ID:7142482

Cakir, M B; Farrar, G R ^[1]

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1. Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08855 (United States)

Given a resonance of known mass, width, and [ital J][sup [ital P][ital C]], we can determine its gluonic branching fraction [ital b][sub [ital R][r arrow][ital g][ital g]] from data on it s production in radiative vector quarkonium decay [ital V][r arrow][gamma][ital R]. For most resonances [ital b][sub [ital R][r arrow][ital g][ital g]] is found to be [similar to]10%, consistent with being [ital q[bar q]] states, but we find that both pseudoscalars observed in the 1440 MeV region have [ital b][sub [ital R][r arrow][ital g][ital g]][similar to]1/2[minus]1, and [ital b]([ital f][sub 0][sup ++][r arrow][ital gg])[similar to]1/2. As data improve, [ital b][sub [ital R][r arrow][ital g][ital g]] should be a useful discriminator between [ital q[bar q]] and gluonic states and may permit quantitative determination of the extent to which a particular resonance is a mixture of glueball and [ital q[bar q]]. We also examine the regime of validity of PQCD for predicting the rate of [ital V][r arrow][gamma][eta][sub [ital [tilde g]]], the extra'' pseudoscalar bound state which would exist if there were light gluinos. From the CUSB limit on peaks in [Upsilon][r arrow][gamma][ital X], the mass range 3 GeV[approx lt][ital m]([eta][sub [ital [tilde g]]])[approx lt]7 GeV can be excluded. An experiment must be significantly more sensitive to exclude an [eta][sub [ital [tilde g]]] lighter than this.

• OSTI ID: 7142482
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 50:5; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

662350 -- Decays of Mesons-- (1992-)
662390 -- Electromagnetic Processes & Properties-- (1992-)
662420* -- Properties of Mesons & Meson Resonances-- (1992-)
662440 -- Properties of Other Particles Including Hypothetical Particles-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR MOMENTUM
BOSONS
BRANCHING RATIO
DECAY
DIMENSIONS
ELEMENTARY PARTICLES
FIELD THEORIES
GLUEBALLS
GLUONS
MASS
PARITY
PARTICLE DECAY
PARTICLE PROPERTIES
POSTULATED PARTICLES
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARKONIUM
RADIATIVE DECAY
SPARTICLES
TENSORS
VECTORS
WIDTH