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Register a new userDecays Z --> ggg and Z-prime --> ggg in the minimal 331 model
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Added by
Fernando Iguazu Ramirez Zavaleta
Publication date
2009
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and research's language is
English
Authors
A. Flores-Tlalpa
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We perform a complete calculation at the one-loop level for the Zggg and Zggg couplings in the context of the minimal 331 model, which predicts the existence of a new Z gauge boson and new exotic quarks. Bose symmetry is exploited to write a compact and manifest SU_C(3)-invariant vertex function for the Vggg (V=Z,Z) coupling. Previous results on the $Zto ggg$ decay in the standard model are reproduced. It is found that this decay is insensitive to the effects of the new exotic quarks. This in contrast with the $Zto ggg$ decay, which is sensitive to both the standard model and exotic quarks, whose branching ratio is larger than that of the $Zto ggg$ transition by about a factor of 4.
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We investigate coherent-elastic neutrino-nucleus scattering ($CE u NS$) in 3-3-1 models for different values of $beta$ in which $beta$ is a parameter used to define the charge operator of the 331 models. We show that the number of events predicted by 331$beta$ model is in agreement with the data given by COHERENT experiment. We evaluate the sensitivity of the mass of Z boson with 90% confidence level (CL) and find that $m_{Z}geq 1.4 $TeV for $beta=-sqrt{3}$ with 90% CL. We perform $chi^2$ fit for liquid Argon, Germanium and NaI detector subsystems, we obtain $m_{Z} geq [2,3.1 ]$ TeV with 90% CL. Our results indicate low-energy high-intensity measurements can provide a valuable probe, complementary to high energy collider searches at LHC and electroweak precision measurements.
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