e~+e~- -> Z~0Z~0 -> bb-bar cc-bar events as model independent probe of colour reconnection effects

摘要

According to the basic properties of QCD, colour reconnection effects can occur in hadronic processes at high energies. The comparison of e~+e~- -> Z~0Z~0 -> qq-bar q'q'-bar events with the superposition of Z~0-qq-bar and Z~0 -> q'q'-bar events from LEP1 would provide an unambiguous model-independent probe. We show that at LEP2 energy, the background processes are negligible if we select only e~+e~- -> Z~0Z~0 -> bb-bar cc-bar events, and limit the measurements in the phase space of on-shell Z~0Z~0 events.