Evidence for a particle produced in association with weak bosons and decaying to a bottom-antibottom quark pair in Higgs boson searches at the Tevatron

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 $p\bar{p}$ collisions at $\sqrt s = 1.96 \text{TeV}$, correspond to integrated luminosities of up to $9.7$ $\text{fb}^{-1}$. The searches are conducted for a Higgs boson with mass in the range $100-150$ $\text{GeV}/c^2$. 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 $135$ $\text{GeV}/c^2$. 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.