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Non BPS topological defect associated with two coupled real field
We investigate a stability equation involving two-component eigenfunctions
which is associated with a potential model in terms of two coupled real scalar
fields, which presents non BPS topological defect.Comment: Revtex, 6 pages, no figures. This work was presented in the XXII
Brazilian National Meeting on Particles and Fields (October/2001), to appear
at http://www.sbf.if.usp.b
Lorentz-violating nonminimal coupling contributions in mesonic hydrogen atoms and generation of photon higher-order derivative terms
We have studied the contributions of Lorentz-violating CPT-odd and CPT-even
nonminimal couplings to the energy spectrum of the mesonic hydrogen and the
higher-order radiative corrections to the effective action of the photon sector
of a Lorentz-violating version of the scalar electrodynamics. By considering
the complex scalar field describes charged mesons (pion or kaon), the
non-relativistic limit of the model allows to attain upper-bounds by analyzing
its contribution to the mesonic hydrogen energy. By using the experimental data
for the strong correction shift and the pure QED transitions , the best upper-bound for the CPT-odd coupling is
and for the CPT-even one is
. Besides, the CPT-odd radiative correction to the
photon action is a dimension-5 operator which looks like a higher-order
Carroll-Field-Jackiw term. The CPT-even radiative contribution to the photon
effective action is a dimension-6 operator which would be a higher-order
derivative version of the minimal CPT-even term of the standard model
extension
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