375 research outputs found
The MSSM at present and future colliders
A brief overview over the phenomenology of the MSSM at present and future
colliders is given. The complementarity of indirect tests of the model via
precision observables and of the information from the direct production of SUSY
particles is emphasized. If the lightest Higgs boson of the MSSM will be
detected, its mass will also play an important role as a precision observable.Comment: 3 pages, 3 figures, to appear in the proceedings of the International
Europhysics Conference on High Energy Physics, Tampere, July 199
Interference effects in MSSM Higgs searches at the LHC
Complex parameters in the MSSM lead to mixing and interference between the
two heavier neutral CP-even and CP-odd Higgs states. These effects can become
very large in the case of almost degenerate states. In a CP-violating benchmark
scenario, we investigate phenomenological implications of such interferences in
view of the LHC searches for heavy Higgs bosons decaying to a pair of
-leptons and produced in gluon fusion and in association with b-quarks.
Strongly destructive effects leave parameter regions unconstrained that would
be regarded as excluded if no interference terms were taken into account.Comment: 5 pages, 2 figures; conference C16-08-03; references updated, some
clarification
Impact of CP-violating interference effects on MSSM Higgs searches
Interference and mixing effects between neutral Higgs bosons in the MSSM with
complex parameters are shown to have a significant impact on the interpretation
of LHC searches for additional Higgs bosons. Complex MSSM parameters introduce
mixing between the CP-even and CP-odd Higgs states and generate CP-violating
interference terms. Both effects are enhanced in the case of almost degenerate
states. Employing as an example an extension of a frequently used benchmark
scenario by a non-zero phase , the interference contributions are
obtained for the production of neutral Higgs bosons in gluon-fusion and in
association with b-quarks followed by the decay into a pair of -leptons.
While the resonant mixing increases the individual cross sections for the two
heavy Higgs bosons and , strongly destructive interference effects
between the contributions involving and leave a considerable
parameter region unexcluded that would appear to be ruled out if the
interference effects were neglected.Comment: 30 pages, 7 figure
Precise prediction for the W boson mass in the MRSSM
The mass of the W boson, , plays a central role for high-precision tests
of the electroweak theory. Confronting precise theoretical predictions with the
accurately measured experimental value provides a high sensitivity to quantum
effects of the theory entering via loop contributions. The currently most
accurate prediction for the W boson mass in the Minimal R-symmetric
Supersymmetric Standard Model (MRSSM) is presented. Employing the on-shell
scheme, it combines all numerically relevant contributions that are known in
the Standard Model (SM) in a consistent way with all MRSSM one-loop
corrections. Special care is taken in the treatment of the triplet scalar
vacuum expectation value that enters the prediction for already at
lowest order. In the numerical analysis the decoupling properties of the
supersymmetric loop contributions and the comparison with the MSSM are
investigated. Potentially large numerical effects of the MRSSM-specific
superpotential couplings are highlighted. The comparison with
existing results in the literature is discussed.Comment: 35 pages, 9 figures; Updated to JHEP version with minor change
Two-loop top and bottom Yukawa corrections to the Higgs-boson masses in the complex MSSM
Results for the two-loop corrections to the Higgs-boson masses of the MSSM
with complex parameters of
from the
Yukawa sector in the gauge-less limit are presented. The corresponding
self-energies and their renormalization have been obtained in the
Feynman-diagrammatic approach. The impact of the new contributions on the Higgs
spectrum is investigated. Furthermore, a comparison with an existing result in
the limit of the MSSM with real parameters is carried out. The new results will
be included in the public code .Comment: 15 pages, 9 figure
NMSSM interpretations of the observed Higgs signal
While the properties of the signal that was discovered in the Higgs searches
at the LHC are consistent so far with the Higgs boson of the Standard Model
(SM), it is crucial to investigate to what extent other interpretations that
may correspond to very different underlying physics are compatible with the
current results. We use the Next-to-Minimal Supersymmetric Standard Model
(NMSSM) as a well-motivated theoretical framework with a sufficiently rich
Higgs phenomenology to address this question, making use of the public tools
HiggsBounds and HiggsSignals in order to take into account comprehensive
experimental information on both the observed signal and on the existing limits
from Higgs searches at LEP, the TeVatron and the LHC. We find that besides the
decoupling limit resulting in a single light state with SM-like properties,
several other configurations involving states lighter or quasi-degenerate with
the one at about 125 GeV turn out to give a competitive fit to the Higgs data
and other existing constraints. We discuss the phenomenology and possible
future experimental tests of those scenarios, and compare the features of
specific scenarios chosen as examples with those arising from a more global
fit.Comment: 46 pages, 23 figures. Version accepted by JHE
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