Effective Multi-Higgs Couplings to Gluons

Standard-Model Higgs bosons are dominantly produced via the gluon-fusion mechanism $gg \to H$ at the LHC, i.e. in a loop-mediated process with top loops providing the dominant contribution. For the measured Higgs boson mass of $\sim 125$ GeV the limit of heavy top quarks provides a reliable approximation as long as the relative QCD corrections are scaled with the full mass-dependent LO cross section. In this limit the Higgs coupling to gluons can be described by an effective Lagrangian. The same approach can also be applied to the coupling of more than one Higgs boson to gluons. We will derive the effective Lagrangian for multi-Higgs couplings to gluons up to N$^4$LO thus extending previous results for more than one Higgs boson. Moreover we discuss gluonic Higgs couplings up to NNLO, if several heavy quarks contribute.Comment: 13 pages, 1 figur

QCD CORRECTIONS TO HIGGS BOSON DECAYS

The two--loop ${\cal O}(\alpha_s G_F m_t^2)$ corrections to the $b\bar b$ decay rate of the Standard Model Higgs boson as well as its production via $e^+e^- \to ZH$ will be presented. These QCD corrections are obtained by using a low-energy theorem for light Higgs bosons compared to the top quark mass. The results yield strong screening effects of the ${\cal O}(G_F m_t^2)$ contributions. After that the two-loop QCD corrections to the $\gamma\gamma$ and gluonic decays of the Higgs bosons of the Standard Model and its minimal supersymmetric extension are discussed. While the corrections to the $\gamma\gamma$ decays remain small of ${\cal O}(\alpha_s)$ they are huge $\sim$ 50 -- 70 \% in the case of the gluonic decays.Comment: 16 pages, latex, 9 figures appended as uuencoded fil

Higgs Boson Production and Decay at the Tevatron

The theoretical status of Higgs boson production and decay at the Tevatron within the Standard Model and its minimal supersymmetric extension is reviewed. The focus will be on the evaluation of higher-order corrections to the production cross sections and their phenomenological implications.Comment: 12 pages, latex, 6 figure

Higgs Production and Decay at Future Machines

Higgs boson production at future colliders within the Standard Model and its minimal supersymmetric extension is reviewed. The predictions for decay rates and production cross sections are presented including all relevant higher-order corrections.Comment: 5 pages, latex, 5 figures, Contribution to the proceedings of the International Europhysics Conference on High-Energy Physics, 19--26 August 1997, Jersusalem, Israe

Gluon fusion production of the Higgs boson in a Calculable Model with one Extra Dimension

In an extension of the Standard Model with one extra dimension and N=1 supersymmetry compactified on R^1/(Z_2 x Z'_2), we compute the Higgs boson decay width into two gluons, relevant to Higgs production in hadronic collisions. At one loop, the decay width is significantly suppressed with respect to the SM. For a compactification radius 1/R = 370 \pm 70 GeV and a Higgs mass m_H = 127 \pm 8 GeV, as expected in the case of a radiatively generated Fayet-Iliopoulos term, we find it to be less than 15% of the SM result.Comment: 9 pages, 3 eps figures, comments and references added, to appear on Phys.Lett.

SUSY-QCD Corrections to Higgs Boson Production at Hadron Colliders

We analyze the next-to-leading order SUSY-QCD corrections to the production of Higgs particles at hadron colliders in supersymmetric extensions of the Standard Model. Besides the standard QCD corrections due to gluon exchange and emission, genuine supersymmetric corrections due to the virtual exchange of squarks and gluinos are present. At both the Tevatron and the LHC, these corrections are found to be small in the Higgs-strahlung, Drell-Yan-like Higgs pair production and vector boson fusion processes.Comment: 11 pages, latex, 3 figures, numerical analysis extended, one figure and one reference adde

Digital Measurement of Differential Time Delay of Pseudo Random Coded Signals Scientific Report No. 6

Digital measurement of differential time delay of pseudorandom coded signal

On the time required for group multiplication

Group multiplication of logical elements by networks having limited inputs and unit delay in computing output functio