The data collected at centre-of-mass energies of 188.6 GeV by ALEPH at LEP, corresponding to an integrated luminosity of 176.2 pb(-1), are analysed in a search for pair-produced charged Hi,ags bosons H +/-. Three analyses are employed to select the tau(+)7 nu(tau)tau(-)<(nu)over bar>tau, c (s) over bar tau(-)<(nu)over bar>(tau) and c (s) over bar s (c) over bar final states. No evidence for a signal is found. Upper limits are set on the production cross section as a function of the branching fraction B(H+--> tau(+)nu(tau)) and of the mass m(H+/-), assuming that the sum of the branching ratios is equal to one. In the framework of a two-Higgs-doublet model, charged Higgs bosons with masses below 65.4 GeV/c(2) are excluded at 95% confidence level independently of the decay mode. (C) 2000 Published by Elsevier Science B.V.
Search for charged Higgs bosons in e(+)e(-) collisions at energies up to root s=189 GeV
ROLANDI, LUIGI;LIGABUE, FRANCO;
2000-01-01
Abstract
The data collected at centre-of-mass energies of 188.6 GeV by ALEPH at LEP, corresponding to an integrated luminosity of 176.2 pb(-1), are analysed in a search for pair-produced charged Hi,ags bosons H +/-. Three analyses are employed to select the tau(+)7 nu(tau)tau(-)<(nu)over bar>tau, c (s) over bar tau(-)<(nu)over bar>(tau) and c (s) over bar s (c) over bar final states. No evidence for a signal is found. Upper limits are set on the production cross section as a function of the branching fraction B(H+--> tau(+)nu(tau)) and of the mass m(H+/-), assuming that the sum of the branching ratios is equal to one. In the framework of a two-Higgs-doublet model, charged Higgs bosons with masses below 65.4 GeV/c(2) are excluded at 95% confidence level independently of the decay mode. (C) 2000 Published by Elsevier Science B.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
