The Asymmetric Leximin Solution

In this article we define and characterize a class of asymmetric leximin solutions, that contains both the symmetric leximin solution of Imai[5] and the two-person asymmetric Kalai-Smorodinsky solution of Dubra [3] as special cases. Solutions in this class combine three attractive features: they are defined on the entire domain of convex n-person bargaining problems, they generally yield Pareto efficient solution outcomes, and asymmetries among bargainers are captured by a single parameter vector. The characterization is based on a strengthening of Dubra’s [3] property Restricted Independence of Irrelevant Alternatives (RIIA). RIIA imposes Nash’s IIA (Nash [9]), under the added condition that the contraction of the feasible set preserves the mutual proportions of players’ utopia values. Our axiom, entitled RIIA for Independent Players (RIP), says RIIA holds for a group of players, given that the contraction of the feasible set does not affect players outside that group

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.

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

Report on use of excess M-area facilities

The purpose of this report is to document the results of a study which investigated the feasibility of physically locating one or more functions that will be required to support the Accelerator Production of Tritium (APT) Project in M-Area facilities at the Savannah River Site (SRS)

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

Characterization of an inertial micro gripper based on adhesion forces

Adhesive forces become predominant in the micro world comparing to the gravity effect implying the development of new micro manipulation strategies. This paper presents the design and conception of a gripper that use the inertial principle for the release (applying a high acceleration, in the order of 10’000g) and the adhesion for catching a micro part of 50μm with the goal of precisely control the position after release. Experiments were conducted and showed a positioning repeatability of 2μm to 6μm depending on the relative humidity with a success rate of more than 90%

Actionneur à deux degrés de liberté pour micro robot mobile

Ce projet présente un actionneur à deux degrés de liberté (mouvement verticale et rotation) pour des micro-robots mobiles. L’actionneur possède un encombrement de 12 x 10.4 x 3 mm3 et une course de 5.5 mm. L’actionnement est basé sur le principe du stick-slip avec des actionneurs piézo-électriques avec des pieds conducteurs pour éviter des fils. L’actionneur est capable de soulever un poids de 2.5 g et présente des vitesses maximales de 0.7 mm/s en verticale et 0.18 rad/s en rotation

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.