Heavy quarkonium production in Z decays

• Autores: Dova, María Teresa; Lacentre, Pablo E.; L3 Collaboration
• Año de publicación: 1999
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Ciencias Exactas; Física; quarkonium production; Z decays; L3 detector
• Institución: Universidad Nacional de La Plata

We report measurements of the inclusive production of heavy quarkonium states in Z decays based on the analysis of 3.6 million hadronic events collected by the L3 detector at LEP. The measurement of inclusive J production and an improved 95% confidence level upper limit on Υ production are presented. In addition, two independent measurements of the ratio, fp , of prompt J mesons to those from B decay are made using two different isolation cuts to separate prompt J mesons from J mesons produced in the decays of b hadrons. The results are: $\text{Br}\text{(}\text{Z}\text{→}\text{J}\text{+}\text{X}\text{)=(3.21±0.21}\text{(stat.)}{}^{\mathrm{+0.19}}{}_{\mathrm{-0.28}}\text{(sys.)}\text{)×10}{}^{\mathrm{-3}}$, Br(Z→ϒ(1S)+X)<4.4×10−5, $\text{f}{}_{\mathrm{<mtext>p</mtext>}}\text{=(7.1±2.1}\text{(stat.)}\text{±1.2}\text{(sys.)}{}^{\mathrm{+1.5}}{}_{\mathrm{-0.8}}\text{(theo.)}\text{)×10}{}^{\mathrm{-2}}$.
Facultad de Ciencias Exactas