93 research outputs found
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%
Supersymmetric mass spectra and the seesaw scale
Supersymmetric mass spectra within two variants of the seesaw mechanism,
commonly known as type-II and type-III seesaw, are calculated using full 2-loop
RGEs and minimal Supergravity boundary conditions. The type-II seesaw is
realized using one pair of 15 and superfields, while the type-III is
realized using three copies of superfields. Using published, estimated
errors on SUSY mass observables attainable at the LHC and in a combined LHC+ILC
analysis, we calculate expected errors for the parameters of the models, most
notably the seesaw scale. If SUSY particles are within the reach of the ILC,
pure mSugra can be distinguished from mSugra plus type-II or type-III seesaw
for nearly all relevant values of the seesaw scale. Even in the case when only
the much less accurate LHC measurements are used, we find that indications for
the seesaw can be found in favourable parts of the parameter space. Since our
conclusions crucially depend on the reliability of the theoretically forecasted
error bars, we discuss in some detail the accuracies which need to be achieved
for the most important LHC and ILC observables before an analysis, such as the
one presented here, can find any hints for type-II or type-III seesaw in SUSY
spectra.Comment: 31 pages, 49 figure
Protease Activity Increases in Plasma, Peritoneal Fluid, and Vital Organs after Hemorrhagic Shock in Rats
Hemorrhagic shock (HS) is associated with high mortality. A severe decrease in blood pressure causes the intestine, a major site of digestive enzymes, to become permeable – possibly releasing those enzymes into the circulation and peritoneal space, where they may in turn activate other enzymes, e.g. matrix metalloproteinases (MMPs). If uncontrolled, these enzymes may result in pathophysiologic cleavage of receptors or plasma proteins. Our first objective was to determine, in compartments outside of the intestine (plasma, peritoneal fluid, brain, heart, liver, and lung) protease activities and select protease concentrations after hemorrhagic shock (2 hours ischemia, 2 hours reperfusion). Our second objective was to determine whether inhibition of proteases in the intestinal lumen with a serine protease inhibitor (ANGD), a process that improves survival after shock in rats, reduces the protease activities distant from the intestine. To determine the protease activity, plasma and peritoneal fluid were incubated with small peptide substrates for trypsin-, chymotrypsin-, and elastase-like activities or with casein, a substrate cleaved by multiple proteases. Gelatinase activities were determined by gelatin gel zymography and a specific MMP-9 substrate. Immunoblotting was used to confirm elevated pancreatic trypsin in plasma, peritoneal fluid, and lung and MMP-9 concentrations in all samples after hemorrhagic shock. Caseinolytic, trypsin-, chymotrypsin-, elastase-like, and MMP-9 activities were all significantly (p<0.05) upregulated after hemorrhagic shock regardless of enteral pretreatment with ANGD. Pancreatic trypsin was detected by immunoblot in the plasma, peritoneal space, and lungs after hemorrhagic shock. MMP-9 concentrations and activities were significantly upregulated after hemorrhagic shock in plasma, peritoneal fluid, heart, liver, and lung. These results indicate that protease activities, including that of trypsin, increase in sites distant from the intestine after hemorrhagic shock. Proteases, including pancreatic proteases, may be shock mediators and potential targets for therapy in shock
A translational study “case report” on the small molecule “energy blocker” 3-bromopyruvate (3BP) as a potent anticancer agent: from bench side to bedside
On-shell neutral Higgs bosons in the NMSSM with complex parameters
The Next-to-Minimal Supersymmetric Standard model (NMSSM) appears as an
interesting candidate for the interpretation of the Higgs-measurement at the
LHC and as a rich framework embedding physics beyond the Standard Model. We
consider the renormalization of the Higgs sector of this model in its
-violating version, and propose a renormalization scheme for the
calculation of on-shell Higgs masses. Moreover, the connection between the
physical states and the tree-level ones is no longer trivial at the radiative
level: a proper description of the corresponding transition thus proves
necessary in order to calculate Higgs production and decays at a consistent
loop order. After discussing these formal aspects, we compare the results of
our mass calculation to the output of existing tools. We also study the
relevance of the on-shell transition-matrix in the example of the width. We find deviations between our full prescription and
popular approximations that can exceed .Comment: 28 pages, 11 figure
Singlet extensions of the standard model at LHC Run 2: benchmarks and comparison with the NMSSM
The Complex singlet extension of the Standard Model (CxSM) is the simplest extension that provides scenarios for Higgs pair production with different masses. The model has two interesting phases: the dark matter phase, with a Standard Model-like Higgs boson, a new scalar and a dark matter candidate; and the broken phase, with all three neutral scalars mixing. In the latter phase Higgs decays into a pair of two different Higgs bosons are possible.
In this study we analyse Higgs-to-Higgs decays in the framework of singlet extensions of the Standard Model (SM), with focus on the CxSM. After demonstrating that scenarios with large rates for such chain decays are possible we perform a comparison between the NMSSM and the CxSM. We find that, based on Higgs-to-Higgs decays, the only possibility to distinguish the two models at the LHC run 2 is through final states with two different scalars. This conclusion builds a strong case for searches for final states with two different scalars at the LHC run 2.
Finally, we propose a set of benchmark points for the real and complex singlet extensions to be tested at the LHC run 2. They have been chosen such that the discovery prospects of the involved scalars are maximised and they fulfil the dark matter constraints. Furthermore, for some of the points the theory is stable up to high energy scales. For the computation of the decay widths and branching ratios we developed the Fortran code sHDECAY, which is based on the implementation of the real and complex singlet extensions of the SM in HDECAY
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