1994/02/04 by M. B. Cakir, Mesut Bahadír Çakír, Glennys R. Farrar +1 · 3 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.50.3268
published as Phys.Rev.D50:3268-3278,1994 · 36pp (inc figs),RU-94-04. (Replaces original which didn't latex correctly and didn't have figures.)
arxiv created 1994/02/04 · openalex publication_date 1994/09/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Given a resonance of known mass, width, and JPC, we can determine its gluonic branching fraction b_R\ensuremath→gg from data on it s production in radiative vector quarkonium decay V\ensuremath→\ensuremathγR. For most resonances b_R\ensuremath→gg is found to be \ensuremath∼10%, consistent with being qq\ifmmode\else\textasciimacron\fi states, but we find that both pseudoscalars observed in the 1440 MeV region have b_R\ensuremath→gg\ensuremath∼1/2-1, and b(f0++\ensuremath→gg)\ensuremath∼1/2. As data improve, b_R\ensuremath→gg should be a useful discriminator between qq\ifmmode\else\textasciimacron\fi and gluonic states and may permit quantitative determination of the extent to which a particular resonance is a mixture of glueball and qq\ifmmode\else\textasciimacron\fi. We also examine the regime of validity of PQCD for predicting the rate of V\ensuremath→\ensuremathγ\mathrm\ensuremathη_g\mathrm\ifmmode \else \~\fi, the ``extra'' pseudoscalar bound state which would exist if there were light gluinos. From the CUSB limit on peaks in \ensuremathΥ\ensuremath→\ensuremathγX, the mass range 3 GeV\ensuremath\lesssimm(\mathrm\ensuremathη_g\mathrm\ifmmode \else \~\fi)\ensuremath\lesssim7 GeV can be excluded. An experiment must be significantly more sensitive to exclude an \mathrm\ensuremathη_g\mathrm\ifmmode \else \~\fi lighter than this.