Extended Iterative Scheme for QCD: Three-point Vertices

In the framework of a generalized iterative scheme introduced previously to account for the non-analytic coupling dependence associated with the renormalization-group invariant mass scale Lambda, we establish the self-consistency equations of the extended Feynman rules (Lambda-modified vertices of zeroth perturbative order) for the three-gluon vertex, the two ghost vertices, and the two vertices of massless quarks. Calculations are performed to one-loop-order, in Landau gauge, and at the lowest approximation level (r=1) of interest for QCD. We discuss the phenomenon of compensating poles inherent in these equations, by which the formalism automatically cancels unphysical poles on internal lines, and the role of composite-operator information in the form of equation-of-motion condensate conditions. The observed near decoupling of the four-gluon conditions permits a solution to the 2-and-3-point conditions within an effective one-parameter freedom. There exists a parameter range in which one solution has all vertex coefficients real, as required for a physical solution, and a narrower range in which the transverse-gluon and massless-quark propagators both exhibit complex-conjugate pole pairs.Comment: 28 pages, 7 figure

CMOS Buck-Boost Power processing circuitry for powerMEMS generators

Accepted versio

A numerical test of the Y-system in the small size limit of the SU(2)x SU(2) Principal Chiral Model

Recently, Kazakov, Gromov and Vieira applied the discrete Hirota dynamics to study the finite size spectra of integrable two dimensional quantum field theories. The method has been tested from large values of the size L down to moderate values using the SU(2) x SU(2) principal chiral model as a theoretical laboratory. We continue the numerical analysis of the proposed non-linear integral equations showing that the deep ultraviolet region L -> 0 is numerically accessible. To this aim, we introduce a relaxed iterative algorithm for the numerical computation of the low-lying part of the spectrum in the U(1) sector. We discuss in details the systematic errors involved in the computation. When a comparison is possible, full agreement is found with previous TBA computations.Comment: 28 pages, 24 figure

Production of neutral MSSM Higgs bosons in e+e−e^+e^- collisions: a complete 1-loop calculation

We present the first complete 1-loop diagrammatic calculation of the cross sections for the neutral Higgs production processes e^+e^-\ra Z^0h^0 and e^+e^-\ra A^0h^0 in the minimal supersymmetric standard model. We compare the results from the diagrammatic calculation with the corresponding ones of the simpler and compact effective potential approximation and discuss the typical size of the differences.Comment: LaTeX, 16 pages, 8 figures appended in a uuencoded file, complete PostScript file available at http://itpaxp1.physik.uni-karlsruhe.de/prep/KA-TP-16-1995/KA-TP-16-199

Quantum effects on Higgs-strahlung events at Linear Colliders within the general 2HDM

The associated production of neutral Higgs bosons with the Z gauge boson is investigated in the context of the future linear colliders, such as the ILC and CLIC, within the general two-Higgs-doublet model (2HDM). We compute the corresponding production cross-sections at one-loop, in full consistency with the available theoretical and phenomenological constraints. We find that the wave-function renormalization corrections to the external Higgs fields are the dominant source of the quantum effects, which turn out to be large and negative, and located predominantly in the region around \tan\beta=1 and moderate values of the parameter \lambda_5 (being \lambda_5 < 0). This behavior can be ultimately traced back to the enhancement potential of the triple Higgs boson self-couplings, a trademark feature of the 2HDM with no counterpart in the Higgs sector of the Minimal Supersymmetric Standard Model. The predicted Higgs-strahlung rates comfortably reach a few tens of femtobarn, which means barely 10^3 - 10^4 events per 500 inverse femtobarn of integrated luminosity. Due to their great complementarity, we argue that the combined analysis of the Higgs-strahlung events and the previously computed one-loop Higgs-pair production processes could be instrumental to probe the structure of the Higgs sector at future linac facilities.Comment: LaTeX, 16 pages, 9 Figures, 2 Tables. Extended discussion, references added, matches published version in Phys. Rev.

Lightly supervised automatic subtitling of weather forecasts

Since subtitling television content is a costly process, there are large potential advantages to automating it, using automatic speech recognition (ASR). However, training the necessary acoustic models can be a challenge, since the available training data usually lacks verbatim orthographic transcriptions. If there are approximate transcriptions, this problem can be overcome using light supervision methods. In this paper, we perform speech recognition on broadcasts of Weatherview, BBC’s daily weather report, as a first step towards automatic subtitling. For training, we use a large set of past broadcasts, using their manually created subtitles as approximate transcriptions. We discuss and and compare two different light supervision methods, applying them to this data. The best training set finally obtained with these methods is used to create a hybrid deep neural networkbased recognition system, which yields high recognition accuracies on three separate Weatherview evaluation sets

A Comprehensive Model of a Doubly Fed Induction Generator for Dynamic Simulations and

Abstract. The doubly fed induction generator (DFIG) is a very suitable generator type for wind turbine applications. However, its operation principles and its control are rather complex. This paper will describe the different steps for modelling and simulating the generator behaviour. A simulation example of the operation of a DFIG in a small power system is presented

Neutral Higgs-pair production at Linear Colliders within the general 2HDM: quantum effects and triple Higgs boson self-interactions

The pairwise production of neutral Higgs bosons is analyzed in the context of the future linear colliders, such as the ILC and CLIC, within the general Two-Higgs-Doublet Model (2HDM). The corresponding cross-sections are computed at the one-loop level in full compliance with the current phenomenological bounds and the stringent theoretical constraints inherent to the consistency of the model. We uncover regions across the 2HDM parameter space, mainly for low tan\beta near 1 and moderate values of the relevant lambda_5 parameter, wherein the radiative corrections to the Higgs-pair production cross sections can comfortably reach 50% This behavior can be traced back to the enhancement capabilities of the trilinear Higgs self-interactions -- a trademark feature of the 2HDM, with no counterpart in the Minimal Supersymmetric Standard Model. Interestingly enough, the quantum effects are positive for energies around 500 GeV, thereby producing a significant enhancement in the expected number of events precisely around the fiducial startup energy of the ILC. The Higgs-pair production rates can be substantial, typically amounting to a few thousand events per 500 inverse femtobarn of integrated luminosity. In contrast, the corrections are negative in the highest energy range (1 TeV). We also compare the exclusive pairwise production of Higgs bosons with the inclusive gauge boson fusion channels leading to 2H+X finals states, and also with the exclusive triple Higgs boson production. We find that these multiparticle final states can be highly complementary in the overall Higgs bosons search strategy.Comment: 42 pages, 23 figures, 10 tables. Accepted in Phys. Rev. D (the published version is shorter

The Higgs Boson Production Cross Section as a Precision Observable?

We investigate what can be learned at a linear collider about the sector of electroweak symmetry breaking from a precise measurement of the Higgs boson production cross section through the process e+e- -> hZ. We focus on deviations from the Standard Model arising in its minimal supersymmetric extension. The analysis is performed within two realistic future scenarios, taking into account all prospective experimental errors on supersymmetric particle masses as well as uncertainties from unknown higher order corrections. We find that information on tan beta and M_A could be obtained from a cross section measurement with a precision of 0.5 - 1 %. Alternatively, information could be obtained on the gaugino mass parameters M_2 and mu if they are relatively small, M_2, mu approximately 200 GeV.Comment: 13 pages, 3 figures. Discussion on experimental errors enlarged, references added and updated. Version to appear in Phys. Rev.