34 research outputs found
Vacuum Stability and Triviality Analyses of the Renormalizable Coloron Model
The renormalizable coloron model is built around a minimally extended color
gauge group, which is spontaneously broken to QCD. The formalism introduces
massive color-octet vector bosons (colorons), as well as several new scalars
and fermions associated with the symmetry breaking sector. In this paper, we
examine vacuum stability and triviality conditions within the context of the
renormalizable coloron model up to a cutoff energy scale of 100~TeV, by
computing the beta-functions of all relevant couplings and determining their
running behavior as a function of the renormalization scale. We constrain the
parameter space of the theory for four separate scenarios based on differing
fermionic content, and demonstrate that the vectorial scenarios are less
constrained by vacuum stability and triviality bounds than the chiral
scenarios. Our results are summarized in exclusion plots for the separate
scenarios, with previous bounds on the model overlaid for comparison. We find
that a 100 TeV hadron collider could explore the entire allowed parameter space
of the chiral models very effectively.Comment: 17 pages, embedded color pdf figures. Typos corrected and appendix on
fermion charges and mass generation adde
Constraints on the Scalar Sector of the Renormalizable Coloron Model
The renormalizable coloron model is the minimal extension of the standard
model color sector, in which the color gauge group is enlarged to SU(3)_{1c} x
SU(3)_{2c}. In this paper we discuss the constraints on this model derived from
the requirements of vacuum stability, tree-level unitarity, electroweak
precision measurements, and from LHC measurements of the properties of the
observed Higgs-like scalar boson. The combination of these theoretical and
experimental considerations strongly constrains the allowed parameter space.
(Erratum appended, March 2014.)Comment: 20 pages, pdf included figures. Brief phenomenological analysis of
additional scalar s-boson added. Erratum appended: an error in the
Higgs-boson gluon-fusion production amplitude arising from the new colored
states is corrected, resulting in stronger constraints on the model parameter
spac
Global Symmetries and Renormalizability of Lee-Wick Theories
In this paper we discuss the global symmetries and the renormalizibility of
Lee-Wick scalar QED. In particular, in the "auxiliary-field" formalism we
identify softly broken SO(1,1) global symmetries of the theory. We introduce
SO(1,1) invariant gauge-fixing conditions that allow us to show in the
two-field formalism directly that the number of superficially divergent
amplitudes in a LW Abelian gauge theory is finite. To illustrate the
renormalizability of the theory, we explicitly carry out the one-loop
renormalization program in LW scalar QED and demonstrate how the counterterms
required are constrained by the joint conditions of gauge- and
SO(1,1)-invariance. We also compute the one-loop beta-functions in LW scalar
QED and contrast them with those of ordinary scalar QED.Comment: 17 pages, 3 eps figures included. Incorporates suggestions by
referee; title change