Search for a Fourth Generation b-quark at LEP-II at sqrt(s)=196-209 GeV
2007 (English)In: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 50, no 3, 507-518 p.Article in journal (Refereed) Published
A search for the pair production of fourth generation b'-quarks was performed using data taken by the DELPHI detector at LEP-II. The analysed data were collected at centre-of-mass energies ranging from 196 to 209 GeV, corresponding to an integrated luminosity of 420 pb(-1). No evidence for a signal was found. Upper limits on BR(b'-> bZ) and BR(b'-> bZ) were obtained for b' masses ranging from 96 to 103 GeV/c(2) stop. These limits, together with the theoretical branching ratios predicted by a sequential four generations model, were used to constrain the value of R-CKM=vertical bar V-cb(') /V-tb'V-tb vertical bar there V-cb', V-tb' and V-tb are elements of the extended CKM matrix.
Place, publisher, year, edition, pages
2007. Vol. 50, no 3, 507-518 p.
IdentifiersURN: urn:nbn:se:su:diva-12432DOI: 10.1140/epjc/s10052-007-0273-zOAI: oai:DiVA.org:su-12432DiVA: diva2:178952