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Title: Visible Cascade Higgs Decays to Four Photons at Hadron Colliders

Abstract

The presence of a new singlet scalar particle a can open up new decay channels for the Higgs boson, through cascades of the form h{yields}2a{yields}X, possibly making discovery through standard model channels impossible. If a is CP odd, its decays are particularly sensitive to new physics. Quantum effects from heavy fields can naturally make h{yields}4g the dominant decay which is difficult to observe at hadron colliders, and is allowed by CERN LEP for m{sub h}>82 GeV. However, there are usually associated decays, either h{yields}2g2{gamma} or h{yields}4{gamma}, which are more promising. The decay h{yields}4{gamma} is a clean channel that can discover both a and h. At the CERN LHC with 300 fb{sup -1} of luminosity, a branching ratio of order 10{sup -4} is sufficient for discovery for a large range of Higgs boson masses. With total luminosity of {approx}8 fb{sup -1}, discovery at the Fermilab Tevatron requires more than 5x10{sup -3} in branching ratio.

Authors:
;  [1];  [2]
  1. Center for Cosmology and Particle Physics, Department of Physics, New York University, New York, New York 10003 (United States)
  2. Theoretical Physics Group, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
Publication Date:
OSTI Identifier:
20957746
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevLett.98.111802; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BEAM LUMINOSITY; BRANCHING RATIO; CERN LHC; CP INVARIANCE; FERMILAB TEVATRON; GEV RANGE 10-100; HADRONS; HIGGS BOSONS; HIGGS MODEL; LEP STORAGE RINGS; MASS; PARTICLE DECAY; PHOTONS; STANDARD MODEL

Citation Formats

Chang, Spencer, Weiner, Neal, and Fox, Patrick J. Visible Cascade Higgs Decays to Four Photons at Hadron Colliders. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.111802.
Chang, Spencer, Weiner, Neal, & Fox, Patrick J. Visible Cascade Higgs Decays to Four Photons at Hadron Colliders. United States. doi:10.1103/PHYSREVLETT.98.111802.
Chang, Spencer, Weiner, Neal, and Fox, Patrick J. Fri . "Visible Cascade Higgs Decays to Four Photons at Hadron Colliders". United States. doi:10.1103/PHYSREVLETT.98.111802.
@article{osti_20957746,
title = {Visible Cascade Higgs Decays to Four Photons at Hadron Colliders},
author = {Chang, Spencer and Weiner, Neal and Fox, Patrick J.},
abstractNote = {The presence of a new singlet scalar particle a can open up new decay channels for the Higgs boson, through cascades of the form h{yields}2a{yields}X, possibly making discovery through standard model channels impossible. If a is CP odd, its decays are particularly sensitive to new physics. Quantum effects from heavy fields can naturally make h{yields}4g the dominant decay which is difficult to observe at hadron colliders, and is allowed by CERN LEP for m{sub h}>82 GeV. However, there are usually associated decays, either h{yields}2g2{gamma} or h{yields}4{gamma}, which are more promising. The decay h{yields}4{gamma} is a clean channel that can discover both a and h. At the CERN LHC with 300 fb{sup -1} of luminosity, a branching ratio of order 10{sup -4} is sufficient for discovery for a large range of Higgs boson masses. With total luminosity of {approx}8 fb{sup -1}, discovery at the Fermilab Tevatron requires more than 5x10{sup -3} in branching ratio.},
doi = {10.1103/PHYSREVLETT.98.111802},
journal = {Physical Review Letters},
number = 11,
volume = 98,
place = {United States},
year = {Fri Mar 16 00:00:00 EDT 2007},
month = {Fri Mar 16 00:00:00 EDT 2007}
}
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