1,852 research outputs found
Renormalization Group Treatment of Nonrenormalizable Interactions
The structure of the UV divergencies in higher dimensional nonrenormalizable
theories is analysed. Based on renormalization operation and renormalization
group theory it is shown that even in this case the leading divergencies
(asymptotics) are governed by the one-loop diagrams the number of which,
however, is infinite. Explicit expression for the one-loop counter term in an
arbitrary D-dimensional quantum field theory without derivatives is suggested.
This allows one to sum up the leading asymptotics which are independent of the
arbitrariness in subtraction of higher order operators. Diagrammatic
calculations in a number of scalar models in higher loops are performed to be
in agreement with the above statements. These results do not support the idea
of the na\"ive power-law running of couplings in nonrenormalizable theories and
fail (with one exception) to reveal any simple closed formula for the leading
terms.Comment: LaTex, 11 page
Higgs Branching Ratios in Constrained Minimal and Next-to-Minimal Supersymmetry Scenarios Surveyed
In the CMSSM the heaviest scalar and pseudo-scalar Higgs bosons decay largely
into b-quarks and tau-leptons because of the large values favored
by the relic density. In the NMSSM the number of possible decay modes is much
richer. In addition to the CMSSM-like scenarios, the decay of the heavy Higgs
bosons is preferentially into top quark pairs (if kinematically allowed),
lighter Higgs bosons or neutralinos, leading to invisible decays. We provide a
scan over the NMSSM parameter space to project the 6D parameter space of the
Higgs sector on the 3D space of the Higgs masses to determine the range of
branching ratios as function of the Higgs boson mass for all Higgs bosons.
Specific LHC benchmark points are proposed, which represent the salient NMSSM
features.Comment: 24 pages, 3 figures, this version is accepted by PLB after minor
modification
Perspectives of direct Detection of supersymmetric Dark Matter in the NMSSM
In the Next-to-Minimal-Supersymmetric-Standard-Model (NMSSM) the lightest
supersymmetric particle (LSP) is a candidate for the dark matter (DM) in the
universe. It is a mixture from the various gauginos and Higgsinos and can be
bino-, Higgsino- or singlino-dominated. Singlino-dominated LSPs can have very
low cross sections below the neutrino background from coherent neutrino
scattering which is limiting the sensitivity of future direct DM search
experiments. However, previous studies suggested that the combination of both,
the spin-dependent (SD) and spin-independent (SI) searches are sensitive in
complementary regions of parameter space, so considering both searches will
allow to explore practically the whole parameter space of the NMSSM. In this
letter, the different scenarios are investigated with a new scanning technique,
which reveals that significant regions of the NMSSM parameter space cannot be
explored, even if one considers both, SI and SD, searches.Comment: 22 pages, 3 figures, this version is accepted by PLB after minor
modification
- …