Hadronic Z decays into three jets are used to test QCD models of colour reconnection (CR). A sensitive quantity is the rate of gluon jets with a gap in the particle rapidity distribution and zero jet charge. Gluon jets are identified by either energy-ordering or by tagging two b-jets. The rates predicted by two string-based tunable CR models, one implemented in JETSET (the GAL model), the other in ARIADNE, are too high and disfavoured by the data, whereas the rates from the corresponding non-CR standard versions of these generators are too low. The data can be described by the GAL model assuming a small value for the R_0 parameter in the range 0.01-0.02.
|Titolo:||Test of colour reconnection models using three-jet events in hadronic Z decays|
|Parole Chiave:||Elementary particles ; physics ; high energy ; collider ; standard model|
|Settore Scientifico Disciplinare:||Settore FIS/01 - Fisica Sperimentale|
|Data di pubblicazione:||2006|
|Digital Object Identifier (DOI):||10.1140/epjc/s10052-006-0017-5|
|Appare nelle tipologie:||01 - Articolo su periodico|