An improved determination of the width of the top quark

0379922 - FZÚ 2013 RIV US eng J - Journal Article
Abazov, V. M. - Abbott, B. - Acharya, B.S. - Kupčo, Alexander - Lokajíček, Miloš … Total 410 authors
An improved determination of the width of the top quark.
Physical Review D: Particles, Fields, Gravitation and Cosmology. Roč. 85, č. 9 (2012), "091104-1"-"091104-8". ISSN 1550-7998
R&D Projects: GA MŠMT LA08047
Institutional research plan: CEZ:AV0Z10100502
Keywords : pair production * CKM matrix * DZERO
Subject RIV: BF - Elementary Particles and High Energy Physics
Impact factor: 4.691, year: 2012
http://prd.aps.org/abstract/PRD/v85/i9/e091104

We present an improved determination of the total width of the top quark, Γt, using 5.4 fb−1 of integrated luminosity collected by the D0 Collaboration at the Tevatron ppˉ Collider. The total width Γt is extracted from the partial decay width Γ(t→Wb) and the branching fraction B(t→Wb). Γ(t→Wb) is obtained from the t-channel single top quark production cross section and B(t→Wb) is measured in ttˉ events. For a top mass of 172.5//GeV, the resulting width is Γt=2.00+0.47−0.43 GeV. This translates to a top-quark lifetime of τt=(3.29+0.90−0.63)×10−25 s. We also extract an improved direct limit on the CKM matrix element 0.81<|Vtb|≤1 at 95% C.L. and a limit of |Vtb′|<0.59 for a high mass fourth generation bottom quark assuming unitarity of the fourth generation quark mixing matrix.
Permanent Link: http://hdl.handle.net/11104/0210773