Searches for Clean Anomalous Gauge Couplings effects at present and future e+e−e^+e^- colliders

We consider the virtual effects of a general type of Anomalous (triple) Gauge Couplings on various experimental observables in the process of electron-positron annihilation into a final fermion-antifermion state. We show that the use of a recently proposed "$Z$-peak subtracted" theoretical description of the process allows to reduce substantially the number of relevant parameters of the model, so that a calculation of observability limits can be performed in a rather simple way. As an illustration of our approach, we discuss the cases of future measurements at LEP2 and at a new 500 GeV linear collider.Comment: 23 pages incl. 5 figures (e-mail [email protected]

Launch window analysis of satellites in high eccentricity or large circular orbits

Numerical methods and computer programs for studying the stability and evolution of orbits of large eccentricity are presented. Methods for determining launch windows and target dates are developed. Mathematical models are prepared to analyze the characteristics of specific missions

Associated production of charged Higgs and top at LHC: the role of the complete electroweak supersymmetric contribution

The process of charged Higgs production in association with a top quark at the LHC has been calculated at the complete NLO electroweak level both in a Two Higgs Doublets Model and in the Minimal Supersymmetric Standard Model, assuming a mSUGRA breaking scheme. We have numerically explored the size of the one-loop corrections in two typical supersymmetric scenarios, with particular attention to the tan beta dependence, and we have found that they remain perturbatively small but possibly sizable, reaching a 20% limit for extreme values of tan beta, when the complete set of Feynman diagrams is taken into account.Comment: 22 pages, 5 figures, reference adde

The roughness of stylolites: Implications of 3D high resolution topography measurements

Stylolites are natural pressure-dissolution surfaces in sedimentary rocks. We present 3D high resolution measurements at laboratory scales of their complex roughness. The topography is shown to be described by a self-affine scaling invariance. At large scales, the Hurst exponent is $\zeta_1 \approx 0.5$ and very different from that at small scales where $\zeta_2 \approx 1.2$. A cross-over length scale at around \L_c =1~mm is well characterized. Measurements are consistent with a Langevin equation that describes the growth of a stylolitic interface as a competition between stabilizing long range elastic interactions at large scales or local surface tension effects at small scales and a destabilizing quenched material disorder.Comment: 4 pages, 4 figure

Supersymmetry spectroscopy in stop-chargino production at LHC

We consider the process of associated stop-chargino production in the MSSM at LHC and show that, at the simplest Born level, the production rate is dramatically sensitive to the choice of the benchmark points, oscillating from potentially "visible" maxima of the picobarn size to much smaller, hardly "visible", values. Adopting a canonical choice of SM type CKM matrices, we also show that in some "visible" cases the total rate exhibits a possibly relevant dependence on tan(beta).Comment: 23 pages, 18 eps figure

A single chain analysis of doped quasi one dimensional spin 1 compounds: paramagnetic versus spin 1/2 doping

We present a numerical study of single chain models of doped spin 1 compounds. We use low energy effective one-dimensional models for both the cases of paramagnetic and spin-1/2 doping. In the case of paramagnetic doping, the effective model is equivalent to the bond disordered spin-1/2 chain model recently analyzed by means of real space renormalization group by Hyman and Yang. By means of exact diagonalizations in the XX limit, we confirm the stability of the Haldane phase for weak disorder. Above a critical amount of disorder, the effective model flows to the so called random singlet fixed point. In the case of spin-1/2 doping, we argue that the Haldane phase should be destabilized even for weak disorder. This picture is not in contradiction with existing experimental data. We also discuss the possible occurrence of (unobserved) antiferromagnetically ordered phases.Comment: 13 pages, 7 included figure

Attitude dynamic of spin-stabilized satellites with flexible appendages

Equations of motion and computer programs have been developed for analyzing the motion of a spin-stabilized spacecraft having long, flexible appendages. Stability charts were derived, or can be redrawn with the desired accuracy for any particular set of design parameters. Simulation graphs of variables of interest are readily obtainable on line using program FLEXAT. Finally, applications to actual satellites, such as UK-4 and IMP-1 have been considered

Semi-inclusive bottom-Higgs production at LHC: The complete one-loop electroweak effect in the MSSM

We present the first complete calculation of the one-loop electroweak effect in the process of semi-inclusive bottom-Higgs production at LHC in the MSSM. The size of the electroweak contribution depends on the choice of the final produced neutral Higgs boson, and can be relevant, in some range of the input parameters. A comparison of the one-loop results obtained in two different renormalization schemes is also performed, showing a very good NLO scheme independence. We further comment on two possible, simpler, approximations of the full NLO result, and on their reliabilty

Logarithmic SUSY electroweak effects on four-fermion processes at TeV energies

We compute the MSSM one-loop contributions to the asymptotic energy behaviour of fermion-antifermion pair production at future lepton-antilepton colliders. Besides the conventional logarithms of Renormalization Group origin, extra SUSY linear logarithmic terms appear of "Sudakov-type". In the TeV range their overall effect on a variety of observables can be quite relevant and drastically different from that obtained in the SM case.Comment: 19 pages and 14 figures, corrected version. e-mail: [email protected]