473 research outputs found
Upper limit on mh in the MSSM and M-SUGRA vs. prospective reach of LEP
The upper limit on the lightest CP-even Higgs boson mass, mh, is analyzed
within the MSSM as a function of tan(beta) for fixed mtop and Msusy. The impact
of recent diagrammatic two-loop results on this limit is investigated. We
compare the MSSM theoretical upper bound on mh with the lower bound obtained
from experimental searches at LEP. We estimate that with the LEP data taken
until the end of 1999, the region mh < 108.2 GeV can be excluded at the 95%
confidence level. This corresponds to an excluded region 0.6 <= tan(beta) <=
1.9 within the MSSM for mtop = 174.3 GeV and Msusy <= 1 TeV. The final
exclusion sensitivity after the end of LEP, in the year 2000, is also briefly
discussed. Finally, we determine the upper limit on mh within the Minimal
Supergravity (M-SUGRA) scenario up to the two-loop level, consistent with
radiative electroweak symmetry breaking. We find an upper bound of mh \approx
127 GeV for mtop = 174.3 GeV in this scenario, which is slightly below the
bound in the unconstrained MSSM.Comment: 10 pages, 3 figure
Z Pole Observables in the MSSM
We present the currently most accurate prediction of Z pole observables such
as sin^2 theta_eff, Gamma_Z, R_b, R_l, and sigma^0_had in the Minimal
Supersymmetric Standard Model (MSSM). We take into account the complete
one-loop results including the full complex phase dependence, all available
MSSM two-loop corrections as well as the full SM results. We furthermore
include higher-order corrections in the MSSM Higgs boson sector, entering via
virtual Higgs boson contributions. For Gamma(Z -> neutralino{1} neutralino{1})
we present a full one-loop calculation. We analyse the impact of the different
sectors of the MSSM with particular emphasis on the effects of the complex
phases. The predictions for the Z boson observables and M_W are compared with
the current experimental values. Furthermore we provide an estimate of the
remaining higher-order uncertainties in the prediction of sin^2 theta_eff.Comment: 53 pages, 20 figures, journal versio
Two-loop electroweak contributions to
A review is given on the quantum correction in the -- mass
correlation at the electroweak two-loop level, as derived from the calculation
of the muon lifetime in the Standard Model. Exact results for and
the -mass prediction including corrections with
fermion loops are presented and compared with previous results of a
next-to-leading order expansion in the top-quark mass.Comment: 14 pages, including 4 figures. Presented at the 5th International
Symposium on Radiative Corrections, (RADCOR-2000), Carmel CA, USA, 11-15
September 200
Discovery Reach of Charged MSSM Higgs Bosons at CMS
We review the 5 sigma discovery contours for the charged MSSM Higgs boson at
the CMS experiment with 30/fb for the two cases M_H+ m_t. In
order to analyze the search reach we combine the latest results for the CMS
experimental sensitivities based on full simulation studies with
state-of-the-art theoretical predictions of MSSM Higgs-boson production and
decay properties. Special emphasis is put on the SUSY parameter dependence of
the 5 sigma contours. The variation of can shift the prospective
discovery reach in tan_beta by up to Delta tan_beta = 40.Comment: 3 pages, 2 figures, talk given at SUSY08, Seoul, Kore
BSM Higgs Physics at the LHC in the Forward Proton Mode
We review the prospects for Central Exclusive Diffractive (CED) production of
Higgs bosons in the SM with a fourth generation of fermions at the LHC using
forward proton detectors installed at 220m and 420m distance around ATLAS and /
or CMS. We discuss the determination of Higgs spin-parity and coupling
structures at the LHC and show that the forward proton mode would provide a
critical information on the CP properties of the Higgs bosons.Comment: 4 pages, 1 figure, talk given by S.H. at the "Physics at the LHC
2010", May 2010, DESY Hamburg, German
Central Exclusive Production of BSM Higgs bosons at the LHC
The prospects for central exclusive diffractive (CED) production of MSSM
Higgs bosons at the LHC are reviewed. These processes can provide important
information on the \cp-even Higgs bosons, allowing to probe interesting
regions of the \MA--\tb parameter plane. The sensitivity of the searches in
the forward proton mode for the Higgs bosons in the so-called CDM-benchmark
scenarios and the effects of fourth-generation models on the CED Higgs
production are briefly discussed.Comment: 7 pages, 4 figures, conference proceeding
Precision Observables in the MSSM: W mass and the muon magnetic moment
The precision observables M_W and g-2 of the muon are discussed in the
framework of the MSSM. Recent progress in the evaluation of the theoretical
predictions is described, and the MSSM predictions are compared with the SM
predictions and the experimental values.Comment: 4 pages, 2 figures. To appear in Proceedings of SUSY06, the 14th
International Conference on Supersymmetry and the Unification of Fundamental
Interactions, UC Irvine, California, 12-17 June 200
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