Measurement of the fraction of t(t)over-bar production via gluon-gluon fusion in p(p)over-bar collisions at root s=1.96 Tev

We present a measurement of the ratio of the t (t) over bar production cross section via gluon-gluon fusion to the total t (t) over bar production cross section in p (p) over bar collisions at root s = 1.96 Tev at the Tevatron. Using a data sample with an integrated luminosity of 955 pb(-1) recorded...

ver descrição completa

Detalhes bibliográficos
Autores: CDF Collaboration, Cabrera, Susana, Cuenca Almenar, Cristóbal, Álvarez González, B., Casal, Bruno, Cuevas, Javier, Gómez, Gervasio, Rodrigo Anoro, Teresa, Ruiz Jimeno, Alberto, Scodellaro, Luca, Vila, Iván, Vilar Cortabitarte, R., Aaltonen, T.
Tipo de documento: artigo
Data de publicação:2009
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositório:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/22130
Acesso em linha:http://hdl.handle.net/10261/22130
Access Level:Acceso aberto
Descrição
Resumo:We present a measurement of the ratio of the t (t) over bar production cross section via gluon-gluon fusion to the total t (t) over bar production cross section in p (p) over bar collisions at root s = 1.96 Tev at the Tevatron. Using a data sample with an integrated luminosity of 955 pb(-1) recorded by the CDF II detector at Fermilab, we select events based on the t (t) over bar decay to lepton + jets. Using an artificial neural network technique we discriminate between t (t) over bar events produced via q (q) over bar annihilation and gg fusion, and find G(f) = sigma(gg -> t (t) over bar/sigma(p (p) over bar -> t (t) over bar) < 0.33 at the 68% confidence level. This result is combined with a previous measurement to obtain the most stringent measurement of this quantity by CDF to date, G(f) = 0.07(-0.07)(+0.15).