Updated Combination of Searches for the Standard Model Higgs Boson at the DØ Experiment in 9 . 7 fb − 1 of Data

Searches for standard model Higgs boson production at the DØ experiment in p¯ p collisions at √ s = 1.96 TeV are carried out for Higgs boson masses (mH) in the range 100 ≤ mH ≤ 200 GeV. Most of these searches use the full Run II data set, corresponding to an integrated luminosity of 9.7 fb −1 , and are combined to maximize the sensitivity to the standard model Higgs boson. In absence of a significant excess above the background expectation, 95% confidence level upper limits are set on the production cross section for a standard model Higgs boson. The upper limits are found to be a factor of 2.11 (0.73) times the predicted standard model cross section for mH = 115 (165) GeV. Under the background-only hypothesis, the corresponding expected limit is 1.46 (0.72) times the standard model prediction. At the same confidence level, these analyses exclude a standard model Higgs boson with a mass in the range 159 < mH < 170 GeV, while the a priori expected exclusion is 156 < mH < 173 GeV. In the range 120 < mH < 140 GeV, the data exhibit an excess over the background prediction of approximately two Gaussian standard deviations.