Search for the Standard Model Higgs Boson at CMS

We searched for the standard model Higgs boson in 11 different decay channels using approxi-mately 5 fb−1 of 7 TeV pp collisions data collected with the CMS detector at LHC. Combining the results we exclude at 95 % confidence level the standard model Higgs boson with a mass between 127.5 and 600 GeV. The expected 95 % confidence level exclusion if the Higgs boson is not present is from 114.5 and 543 GeV. The observed exclusion is weaker than expected at low mass because of some excess of events observed in the data. The most significant excess is found at 125 GeV with a local significance of 2.8σ, a global significance of 0.8σ in the full search range and of 2.1σ in the range 110–145 GeV. The excess is consistent both with background fluctuation and a standard model Higgs boson with mass of about 125 GeV. More data are needed to investigate its origin. 1 Analysis strategy A search for the Standard Model (SM) Higgs Boson 1,2 is carried out in the mass range from 110 and 600 GeV in the decay modes summarized in Table 1, along with the corresponding integrated luminosity, the number of subchannels, the investigated mass range and the approximate Higgs boson mass resolution. At mass below approximately 130 GeV the sensitivity is dominated by γγ and ZZ(∗) → 4 ` decay channels, between 130 and 200 GeV by the WW channel and above 200 GeV various ZZ channels. Table 1: The 11 Higgs boson search channels. The most relevant information is indicated for each of the analyses. Channel mH range Luminosity Sub- mH Comment(GeV) (fb−1) channels resolution H → γγ 110–150 4.8 2 1–2 % updated H → ττ → eτh/µτh/eµ+X 110–145 4.6 9 20% H → ττ → µµ+X 110–140 4.5 3 20 % new WH → eµτh/µµτh + ν’s 100–140 4.7 2 20 % ne