Direct Top-Quark Width Measurement at CDF
We present a measurement of the top-quark width in the lepton+jets decay channel of tt̅ events produced in pp̅ collisions at Fermilab’s Tevatron collider and collected by the CDF II detector. From a data sample corresponding to 4.3 fb-1 [fb superscript -1] of integrated luminosity, we identify 756...
| Main Authors: | , , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Physical Society
2011
|
| Online Access: | http://hdl.handle.net/1721.1/62563 https://orcid.org/0000-0002-6047-4211 |
| Summary: | We present a measurement of the top-quark width in the lepton+jets decay channel of tt̅ events produced in pp̅ collisions at Fermilab’s Tevatron collider and collected by the CDF II detector. From a data sample corresponding to 4.3 fb-1 [fb superscript -1] of integrated luminosity, we identify 756 candidate events. The top-quark mass and the mass of the hadronically decaying W boson that comes from the top-quark decay are reconstructed for each event and compared with templates of different top-quark widths (Γt) [gamma subscript t] and deviations from nominal jet energy scale (ΔJES)[delta subscript JES] to perform a simultaneous fit for both parameters, where ΔJES [delta subscript JES] is used for the in situ calibration of the jet energy scale. By applying a Feldman-Cousins approach, we establish an upper limit at 95% confidence level (CL) of Γt<7.6 GeV [gamma subscript t<7.6 GeV] and a two-sided 68% CL interval of 0.3 GeV<Γt<4.4 GeV [GeV<gamma subscript t<4.4 GeV]] for a top-quark mass of 172.5 GeV/c2 [GeV / c superscript 2], which are consistent with the standard model prediction. |
|---|