HERA prospects on Compositeness and New Vector Bosons

The absence of deviations from the Standard Model for the differential cross section ${d\sigma}/{dQ^2}$ at HERA is used to set limits on electron quark compositeness scale and on new vector bosons, especially the hadrophilic one recently introduced as a possible explanation for LEP/SLC and CDF anomalies.Comment: Latex file, 7 pages and 1 ps fig, few comments on others experiments are added, results are unchanged. To appear in Phys. Let.

TOP-INDUCED ELECTROWEAK BREAKING IN THE MINIMAL SUPERSYMMETRIC STANDARD MODEL

Severe constraints on parameters of the minimal supersymmetric standard model follow from a dynamical electroweak symmetry breaking mechanism dominated by top and stop loops. In particular, the lightest Higgs boson mass is expected to be smaller than 100 GeV.Comment: 10 pages, Latex, 6 Postcript Figure

Probing quark compositeness at hadronic colliders : the case of polarized beams

A new handed interaction between subconstituents of quarks could be at the origin of some small parity violating effects in one-jet inclusive production. Within a few years, the Relativistic Heavy Ion Collider (RHIC) will be used as a polarized proton-proton collider. In this context, we analyse the possibilities of disentangling some new parity violating effects from the standard spin asymmetries which are expected due to the Standard Model QCD-Weak interference. We also explore the possibilities of placing some more stringent limits on the quark compositeness scale $\Lambda$ thanks to measurements of such spin asymmetries.Comment: 10 pages, Latex, 4 figures to be appende

Hadrophilic Z': and explanation of LEP1, SLC and CDF anomalies?

In order to explain possible departures from the Standard Model predictions of $b\overline{b}$ and $c\overline{c}$ production at Z peak, we propose the existence of a Z' vector boson with enhanced couplings to quarks. We first show that this proposal is perfectly consistent with the full set LEP1/SLC results. We then show that there is a predicted range for enhanced Z' $q\overline{q}$ couplings which explains, for Z' masses in the TeV range, the excess of dijet events seen at CDF and leads to visible deviations at LEP2