2004/12/31 by Hooman Davoudiasl, Tao Han, Heather E. Logan
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Particle Detector Development and Performance #Particle physics theoretical and experimental studies #hep-ex #hep-ph
paper · pdf · doi:10.1103/physrevd.71.115007
published as Phys.Rev.D71:115007,2005 · 21 pages, 1 figure; v2: added refs, added discussion of invisible Higgs mass extraction from cross sections at LHC; v3: minor clarifications in text, version to appear in PRD
arxiv created 2005/05/31 · openalex publication_date 2005/06/17 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
A Higgs boson lighter than 2mW that decays mostly into invisible channels (e.g., dark matter particles) is theoretically well-motivated. We study the prospects for discovery of such an invisible Higgs, hinv, at the LHC and the Tevatron in three production modes: (1) in association with a Z, (2) through weak boson fusion (WBF), and (3) accompanied by a jet. In the Z+hinv channel, we show that the LHC can yield a discovery signal above 5\ensuremathσ with 10 fb^\ensuremath-1 of integrated luminosity for a Higgs mass of 120 GeV. With 30 fb^\ensuremath-1 the discovery reach extends up to a Higgs mass of 160 GeV. We also study the extraction of the hinv mass from production cross sections at the LHC, and find that combining WBF and Z+hinv allows a relatively model-independent determination of the hinv mass with an uncertainty of 35--50 GeV (15--20 GeV) with 10 (100) fb^\ensuremath-1. At the Tevatron, a 3\ensuremathσ observation of a 120 GeV hinv in any single channel is not possible with less than 12 fb^\ensuremath-1 per detector. However, we show that combining the signal from WBF with the previously studied Z+hinv channel allows a 3\ensuremathσ observation of hinv with 7 fb^\ensuremath-1 per detector. Because of overwhelming irreducible backgrounds, hinv+j is not a useful search channel at either the Tevatron or the LHC, despite the larger production rate.