Combined upper limit on Standard Model Higgs boson production at CDF

Abstract

The Higgs boson is the only elementary particle predicted by the Standard Model (SM) that has neither been confirmed nor refuted. The CDF collaboration has performed SM Higgs searches in many channels using $p\pbar$ collisions at a centre-of-mass energy $\sqrt{s}=1.96\tev$. We present the latest combined Higgs boson search at CDF. Since the previous year's combination, the sensitivity is increased through the addition of new channels, the improvement of existing channels and the addition of new data samples. We also use the latest parton distribution functions and $gg \rightarrow H$ theoretical cross sections when modelling the signal event yields. Using integrated luminosities of up to 8.2 $\invfb$, we observe a good agreement between data and the background prediction. Since we do not see a Higgs boson excess, we set 95% CL upper limits on the Higgs boson cross section in the range between 100 and 200 $\gevcc$, with 5 $\gevcc$ increments. The observed (expected) limits for a 115 and a 165 $\gevcc$ Higgs boson are 1.55 (1.49) and 0.75 (0.79) $\times$ SM, respectively. Since last year, the Higgs boson excluded range by CDF is extended to 156.5 - 173.7 and 100 - 104.5 $\gevcc$.