18 research outputs found
Radiative contribution to neutrino masses and mixing in SSM
In an extension of the minimal supersymmetric standard model (popularly known
as the SSM), three right handed neutrino superfields are introduced to
solve the -problem and to accommodate the non-vanishing neutrino masses
and mixing. Neutrino masses at the tree level are generated through parity
violation and seesaw mechanism. We have analyzed the full effect of one-loop
contributions to the neutrino mass matrix. We show that the current three
flavour global neutrino data can be accommodated in the SSM, for both
the tree level and one-loop corrected analyses. We find that it is relatively
easier to accommodate the normal hierarchical mass pattern compared to the
inverted hierarchical or quasi-degenerate case, when one-loop corrections are
included.Comment: 51 pages, 14 figures (58 .eps files), expanded introduction, other
minor changes, references adde
Higgs Boson Masses in the Complex NMSSM at One-Loop Level
The Next-to-Minimal Supersymmetric Extension of the Standard Model (NMSSM)
with a Higgs sector containing five neutral and two charged Higgs bosons allows
for a rich phenomenology. In addition, the plethora of parameters provides many
sources of CP violation. In contrast to the Minimal Supersymmetric Extension,
CP violation in the Higgs sector is already possible at tree-level. For a
reliable understanding and interpretation of the experimental results of the
Higgs boson search, and for a proper distinction of Higgs sectors provided by
the Standard Model or possible extensions, the Higgs boson masses have to be
known as precisely as possible including higher-order corrections. In this
paper we calculate the one-loop corrections to the neutral Higgs boson masses
in the complex NMSSM in a Feynman diagrammatic approach adopting a mixed
renormalization scheme based on on-shell and conditions. We study
various scenarios where we allow for tree-level CP-violating phases in the
Higgs sector and where we also study radiatively induced CP violation due to a
non-vanishing phase of the trilinear coupling in the stop sector. The
effects on the Higgs boson phenomenology are found to be significant. We
furthermore estimate the theoretical error due to unknown higher-order
corrections by both varying the renormalization scheme of the top and bottom
quark masses and by adopting different renormalization scales. The residual
theoretical error can be estimated to about 10%
Peccei-Quinn NMSSM in the light of 125 GeV Higgs
We study the phenomenology of the Peccei-Quinn invariant extension of the
next-to-minimal supersymmetric standard model (NMSSM) in view of the recent
discovery of a 125 GeV Higgs boson. The minimal model having no quadratic and
cubic terms of the NMSSM singlet field predicts a light singlino-like lightest
supersymmetric particle (LSP). The model is strongly constrained by the Higgs
invisible decay and the dark matter characteristic of the LSP, while some
constraints can be relaxed by assuming that the saxion, the CP-even companion
of the axion in the Peccei-Quinn sector, causes a late-time entropy production
diluting the thermal LSP density. The collider signal of the model contains
multi-jet and plus missing energy, which can be discovered in the early
stage of the 14 TeV LHC running.Comment: 40 pages, 10 figures, 6 tables. v3: references added, several
statements added and corrected, comments on the small tadpole soft term added
in sec. 2.