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Title: Testing grand unification at the CERN LHC and SLHC

Abstract

We examine the possibility of measuring the three gauge couplings at high scales at the Large Hadron Collider (LHC), in order to see the first steps as they run toward grand unification at much higher energies. Using the minimal supersymmetric standard model (MSSM) with sparticle masses of several hundred GeV as an example of a theory in which the couplings do unify at very high energies, we find that the processes pp{yields}l{sup +}{nu}, pp{yields}l{sup +}l{sup -}, and pp{yields}{gamma}j can be useful to discriminate the SM from the MSSM with masses at the few hundred GeV scale and determine that the couplings are converging at better than the SM prediction toward the GUT scale. Such measurements indirectly probe the existence of lower mass states, charged under the SM gauge groups, but which may be difficult to produce directly or extract from backgrounds at the LHC.

Authors:
 [1];  [2]
  1. Department. of Physics and Astronomy, University of Rochester, Rochester, New York (United States)
  2. High Energy Physics Division, Argonne National Lab, Argonne, Illinois (United States)
Publication Date:
OSTI Identifier:
20929576
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevD.75.115014; (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; CERN LHC; GEV RANGE 100-1000; MASS; PROTON-PROTON INTERACTIONS; SPARTICLES; STANDARD MODEL; SUPERSYMMETRY

Citation Formats

Rainwater, D., and Tait, T. M. P. Testing grand unification at the CERN LHC and SLHC. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.115014.
Rainwater, D., & Tait, T. M. P. Testing grand unification at the CERN LHC and SLHC. United States. doi:10.1103/PHYSREVD.75.115014.
Rainwater, D., and Tait, T. M. P. Fri . "Testing grand unification at the CERN LHC and SLHC". United States. doi:10.1103/PHYSREVD.75.115014.
@article{osti_20929576,
title = {Testing grand unification at the CERN LHC and SLHC},
author = {Rainwater, D. and Tait, T. M. P.},
abstractNote = {We examine the possibility of measuring the three gauge couplings at high scales at the Large Hadron Collider (LHC), in order to see the first steps as they run toward grand unification at much higher energies. Using the minimal supersymmetric standard model (MSSM) with sparticle masses of several hundred GeV as an example of a theory in which the couplings do unify at very high energies, we find that the processes pp{yields}l{sup +}{nu}, pp{yields}l{sup +}l{sup -}, and pp{yields}{gamma}j can be useful to discriminate the SM from the MSSM with masses at the few hundred GeV scale and determine that the couplings are converging at better than the SM prediction toward the GUT scale. Such measurements indirectly probe the existence of lower mass states, charged under the SM gauge groups, but which may be difficult to produce directly or extract from backgrounds at the LHC.},
doi = {10.1103/PHYSREVD.75.115014},
journal = {Physical Review. D, Particles Fields},
number = 11,
volume = 75,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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