A combined search for the standard model Higgs boson at √s = 1.96 TeV

Authors

V. M. Abazov, Joint Institute for Nuclear Research, Dubna, Russia
Kenneth A. Bloom, University of Nebraska-LincolnFollow
Gregory Snow, University of Nebraska-LincolnFollow
D0 Collaboration

Document Type

Article

Date of this Version

April 2008

Comments

Published in Physics Letters B 663 (2008) 26–36. Copyright © 2008 Elsevier B.V. Used by permission.

Abstract

We present new results of the search for WH → ℓνbb production in pp collisions at a center-of-mass energy of √s = 1.96 TeV, based on a dataset with integrated luminosity of 0.44 fb⁻¹. We combine these new results with previously published searches by the D0 collaboration, for WH and ZH production analyzed in the E_T^bb final state, for ZH (→ℓ⁺ℓ^-bb) production, for WH (→WWW) production, and for H (→WW) direct production. No signal-like excess is observed either in the WH analysis or in the combination of all D0 Higgs boson analyses.We set 95% C.L. (expected) upper limits on σ(pp→WH)×B (H →bb) ranging from 1.6 (2.2) pb to 1.9 (3.3) pb for Higgs boson masses between 105 and 145 GeV, to be compared to the theoretical prediction of 0.13 pb for a Standard Model (SM) Higgs boson with mass m_H = 115 GeV. After combination with the other D0 Higgs boson searches, we obtain for m_H = 115 GeV an observed (expected) limit 8.5 (12.1) times higher than the SM predicted Higgs boson production cross section. For m_H = 160 GeV, the corresponding observed (expected) ratio is 10.2 (9.0).