Search for the standard model Higgs boson in $ZH\rightarrow ℓ^+ℓ^−b\bar b$ production with the D0 detector in $9.7\ \text{fb}^{ -1}$ of $p\bar p$ collisions at $\sqrt s=1.96\ \text{TeV}$

Abstract

We present a search for the standard model (SM) Higgs boson produced in association with a Z boson in 9.7 fb−1 of pp¯ collisions collected with the D0 detector at the Fermilab Tevatron Collider at s=1.96 TeV. Selected events contain one reconstructed Z→e+e− or Z→μ+μ− candidate and at least two jets, including at least one jet identified as likely to contain a b quark. To validate the search procedure, we also measure the cross section for ZZ production in the same final state. It is found to be consistent with its SM prediction. We set upper limits on the ZH production cross section times branching ratio for H→bb¯ at the 95% C.L. for Higgs boson masses 90≤MH≤150 GeV. The observed (expected) limit for MH=125 GeV is 7.1 (5.1) times the SM cross section.