Discriminating different Z{sup '}'s via asymmetries at the LHC

Journal Article · Sun May 01 00:00:00 EDT 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.83.094022· OSTI ID:21541609

Zhongqiu, Zhou; Bo, Xiao; Youkai, Wang ^[1]; Shouhua, Zhu ^[1]

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1. Institute of Theoretical Physics State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China)

In practice the asymmetry, which is defined based on the angular distribution of the final states in scattering or decay processes, can be utilized to scrutinize underlying dynamics in and/or beyond the standard model (BSM). As one of the possible BSM physics which might be discovered early at the LHC, extra neutral gauge bosons Z{sup '}'s are theoretically well motivated. Once Z{sup '}'s are discovered at the LHC, it is crucial to discriminate different Z{sup '}'s in various BSM. In principle such a task can be accomplished by measuring the angular distribution of the final states which are produced via Z{sup '}-mediated processes. In the real data analysis, asymmetry is always adopted. In the literature several asymmetries have been proposed at the LHC. Based on these works, we stepped further on to study how to optimize the asymmetries in the left-right model and the sequential standard model, as the examples of BSM. In this paper, we examined four kinds of asymmetries, namely, rapidity-dependent forward-backward asymmetry, oneside forward-backward asymmetry, central charge asymmetry, and edge charge asymmetry (see text for details), with l{sup +}l{sup -} (l=e, {mu}), bb, and tt as the final states. In the calculations with bb and tt final states, the QCD-induced higher-order contributions to the asymmetric cross section were also included. For each kind of final state, we estimated the four kinds of asymmetries and especially the optimal cut usually associated with the definition of the asymmetry. Our numerical results indicated that the capacity to discriminate Z{sup '} models can be improved by imposing the optimal cuts.

• OSTI ID: 21541609
• Journal Information: Physical Review. D, Particles Fields, Vol. 83, Issue 9; Other Information: DOI: 10.1103/PhysRevD.83.094022; (c) 2011 American Institute of Physics; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR DISTRIBUTION
ASYMMETRY
BOSONS
CERN LHC
CROSS SECTIONS
PARTICLE DECAY
PARTICLE RAPIDITY
QUANTUM CHROMODYNAMICS
SCATTERING
STANDARD MODEL
ACCELERATORS
CYCLIC ACCELERATORS
DECAY
DISTRIBUTION
FIELD THEORIES
GRAND UNIFIED THEORY
MATHEMATICAL MODELS
PARTICLE MODELS
PARTICLE PROPERTIES
QUANTUM FIELD THEORY
STORAGE RINGS
SYNCHROTRONS
UNIFIED GAUGE MODELS