17,388 research outputs found
Atomic parity violation in the economical 3-3-1 model
The deviation \de Q_{\mathrm{W}} of the weak charge from its standard model
prediction due to the mixing of the boson with the charged bilepton as
well as of the boson with the neutral and the real part of the
non-Hermitian neutral bilepton in the economical 3-3-1 model is
established. Additional contributions to the usual \de Q_\mathrm{W}
expression in the extra models and the left-right models are
obtained. Our calculations are quite different from previous analyzes in this
kind of the 3-3-1 models and give the limit on mass of the boson, the
and mixing angles with the more appropriate values: $M_{Z'} > 564\
\mathrm{GeV}, -0.018<\sin \va < 0|\sin \theta| < 0.043$.Comment: replace with version to appear in Phys. Lett.
Supersymmetric economical 3-3-1 model
The supersymmetric extension of the economical 3-3-1 model is presented. The
constraint equations and the gauge boson identification establish a relation
between the vacuum expectation values (VEVs) at the top and bottom elements of
the Higgs triplet and its supersymmetric counterpart .
Because of this relation, the exact diagonalization of neutral gauge boson
sector has been performed. The gauge bosons and their associated Goldstone ones
mix in the same way as in non-supersymmetric version. This is also correct in
the case of gauginos. The eigenvalues and eigenstates in the Higgs sector are
derived. The model contains a heavy neutral Higgs boson with mass equal to
those of the neutral non-Hermitian gauge boson and a charged scalar with
mass equal to those of the boson in the standard model, i. e. . This result is in good agreement with the present
estimation: GeV, CL= 95 %. We also show that the boson
sector and the fermion sector gain masses in the same way as in the
non-supersymmetric case.Comment: 33 page
A simple model of gauged lepton and baryon charges
We argue that simpler fermionic contents, responsible for the extension of
the standard model with gauged lepton and baryon charges, can be constructed by
assuming existence of so-called leptoquarks (j,k) with exotic electric charges
q_j=1/2, q_k=-1/2. Some new features in our model are that (i) as the natural
consequences of anomaly cancelation the right-handed neutrinos exist, and the
number of the observed fermion families is equal to the number of the
fundamental colors; (ii) although the lepton and baryon charges are conserved,
the neutrinos can obtain small masses through the type I seesaw mechanism in
similarity to the standard context, and the baryogenesis can be generated in
several cases. They all are natural results due to the spontaneous breaking of
these charges. Some constraints on the new physics via flavor changing and
related phenomenologies such as the stable scalar with anomalous electric
charge and interested processes at colliders are also discussed.Comment: 13 pages, revised versio
The entanglement dynamics of interacting qubits embedded in a spin environment with Dzyaloshinsky-Moriya term
We investigate the entanglement dynamics of two interacting qubits in a spin
environment, which is described by an XY model with Dzyaloshinsky-Moriya (DM)
interaction. The competing effects of environmental noise and interqubit
coupling on entanglement generation for various system parameters are studied.
We find that the entanglement generation is suppressed remarkably in
weak-coupling region at quantum critical point (QCP). However, the suppression
of the entanglement generation at QCP can be compensated both by increasing the
DM interaction and by decreasing the anisotropy of the spin chain. Beyond the
weak-coupling region, there exist resonance peaks of concurrence when the
system-bath coupling equals to external magnetic field. We attribute the
presence of resonance peaks to the flat band of the self-Hamiltonian. These
peaks are highly sensitive to anisotropy parameter and DM interaction.Comment: 8 pages, 9 figure
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