The <math>ηc</math> <math>→</math> <math> pp</math> Decay and a Quark-Diquark Model of the Nucleon: the Contribution of Scalar-Vector Diquark Transition

Nota de FísicaPublicado

The $<math>\eta_c</math>$ $<math>\rightarrow</math>$ $<math> p\bar{p}</math>$ Decay and a Quark-Diquark Model of the Nucleon: the Contribution of Scalar-Vector Diquark Transition

M. Anselmino; F. Caruso; Sérgio Joffily; José Soares

1991

Autores: M. Anselmino; F. Caruso; Sérgio Joffily; José Soares
Tipo: Nota de Física
Estado: Publicado
Fecha de publicación: 1991
Descripción: The <math>\eta_c\,\!</math> decay into proton-antiproton cannot be explained by a lowest order perturbative QCD quark scheme. Trying to improve a previous result where diquarks were also considered as nucleon's constituents, the contribution of the spin-flip transition between scalar and vector diquarks inside the nucleon is computed and is shown to be strictly zero. This result excludes the possibility of understanding why this decay is experimentally observed with a branching ratio much greater than those of other charmonium decays into the same final state, <math>\chi 0,1,2\,\!</math> <math> \rightarrow p\bar{p}\,\!</math>, successfully described by <math> p QCD\,\!</math> in terms of quark and diquark components of the protons. A theoretical explanation of this decay rate is then still lacking and it is suggested that pseudoscalar glueballs might play an important role in solving the puzzle. The experimental results are also briefly discussed.
Año: 1991
Número: CBPF-NF-017/91
Vínculo con tesis: No
Vínculo con beca: No