No abstract

We combine searches by the CDF and D0 Collaborations for the associated production of a Higgs boson with a W or Z boson and subsequent decay of the Higgs boson to a bottom-antibottom quark pair. The data, originating from Fermilab Tevatron pp collisions at √ s = 1.96 TeV, correspond to integrated luminosities of up to 9.7 fb −1 . The searches are conducted for a Higgs boson with mass in the range 100-150 GeV/c 2 . We observe an excess of events in the data compared with the background predictions, which is most significant in the mass range between 120 and 135 GeV/c 2 . The largest local significance is 3.3 standard deviations, corresponding to a global significance of 3.1 standard deviations. We interpret this as evidence for the presence of a new particle consistent with the standard model Higgs boson, which is produced in association with a weak vector boson and decays to a bottom-antibottom quark pair.

We perform a combination of searches for standard model Higgs boson production in p p collisions recorded by the D0 detector at the Fermilab Tevatron Collider at a center of mass energy of ffiffi ffi s p ¼ 1:96 TeV. The different production and decay channels have been analyzed separately, with integrated luminosities of up to 9:7 fb À1 and for Higgs boson masses 90 M H 200 GeV. We combine these final states to achieve optimal sensitivity to the production of the Higgs boson. We also interpret the combination in terms of models with a fourth generation of fermions, and models with suppressed Higgs boson couplings to fermions. The result excludes a standard model Higgs boson at 95% C.L. in the ranges 90 < M H < 101 GeV and 157 < M H < 178 GeV, with an expected exclusion of 155 < M H < 175 GeV. In the range 120 < M H < 145 GeV, the data exhibit an excess over the expected background of up to 2 standard deviations, consistent with the presence of a standard model Higgs boson of mass 125 GeV.

We measure the inclusive single muon charge asymmetry and the like-sign dimuon charge asymmetry in pp collisions using the full data set of 10.4 fb −1 collected with the D0 detector at the Fermilab Tevatron. The standard model predictions of the charge asymmetries induced by CP violation are small in magnitude compared to the current experimental precision, so non-zero measurements could indicate new sources of CP violation. The measurements differ from the standard model predictions of CP violation in these asymmetries with a significance of 3.6 standard deviations. These results are interpreted in a framework of B meson mixing within the CKM formalism to measure the relative width difference ∆Γ d /Γ d between the mass eigenstates of the B 0 meson system, and the semileptonic charge asymmetries a

We report the combination of recent measurements of the helicity of the W boson from top quark decay by the CDF and D0 collaborations, based on data samples corresponding to integrated luminosities of 2:7-5:4 fb À1 of p p collisions collected during Run II of the Fermilab Tevatron collider. Combining measurements that simultaneously determine the fractions of W bosons with longitudinal (f 0 ) and righthanded (f þ ) helicities, we find f 0 ¼ 0:722 AE 0:081½AE0:062ðstatÞ AE 0:052ðsystÞ and f þ ¼ À0:033 AE 0:046½AE0:034ðstatÞ AE 0:031ðsystÞ. Combining measurements where one of the helicity fractions is fixed to the value expected in the standard model, we find f 0 ¼ 0:682 AE 0:057½AE0:035ðstatÞ AE 0:046ðsystÞ for fixed f þ and f þ ¼ À0:015 AE 0:035½AE0:018ðstatÞ AE 0:030ðsystÞ for fixed f 0 . The results are consistent with standard model expectations.