Measurement of the W boson helicity in top quark decays at D0
2007 (English)In: Physical Review D. Particles and fields, ISSN 0556-2821, E-ISSN 1089-4918, Vol. 75, no 3, 031102- p.Article in journal (Refereed) Published
We present a measurement of the fraction f(+) of right-handed W bosons produced in top quark decays, based on a candidate sample of tt events in the l + jets and dilepton decay channels corresponding to an integrated luminosity of 370 pb(-1) collected by the D0 detector at the Fermilab Tevatron pp Collider at root s = 1.96 TeV. We reconstruct the decay angle theta* for each lepton. By comparing the cos theta* distribution from the data with that for the expected background and signal for various values of f(+) (where we assume that the fraction of longitudinally-polarized W bosons has the standard model value of 0.70), we find f(+) = 0.056 +/- 0.080 (stat) +/- 0.057 (syst) (f(+) < 0.23 at 95% C. L.), consistent with the standard model prediction of f(+) = 3.6 X 10(-4).
Place, publisher, year, edition, pages
2007. Vol. 75, no 3, 031102- p.
IdentifiersURN: urn:nbn:se:uu:diva-148115DOI: 10.1103/PhysRevD.75.031102ISI: 000244534800002OAI: oai:DiVA.org:uu-148115DiVA: diva2:401301
D0 Collaboration, for complete list of authors see article2011-03-022011-03-02Bibliographically approved