Low-energy phenomenology of superstring-inspired E6 models

Physics of mirror fermions

The top quark is the heaviest elementary particle observed to date. Its large mass makes the top quark an ideal laboratory to test predictions of perturbation theory concerning heavy quark production at hadron colliders. The top quark is also a powerful probe for new phenomena beyond the Standard Model (SM) of particle physics. In addition, the top quark mass is a crucial parameter for scrutinizing the SM in electroweak precision tests and for predicting the mass of the yet unobserved Higgs boson. Ten years after the discovery of the top quark at the Fermilab Tevatron, top quark physics has entered an era where detailed measurements of top quark properties are undertaken. In this paper an introduction to the phenomenology of top quark production in hadron collisions is given, the lessons learned in Tevatron Run I are summarized and the first Run II results are discussed. A brief outlook of the possibilities of top quark research at the Large Hadron Collider, currently under construction at CERN, is included.

/pdf/top-quark-physics-in-hadron-collisions-1tkfdpidnl.pdf

Top quark physics in hadron collisions

A comprehensive review of the phenomenology of the conventional Higgs boson is presented. The fundamentals of the standard model of electroweak interactions are reviewed. Experimental limits on light Higgs bosons are assessed and prospects for further experimental searches are evaluated.

The Higgs boson

Determination of αs and the Z0 mass from measurements of the total hadronic cross section in e+e- annihilation

The R ratio for e/sup +/e/sup -/ annihilation into hadronic final states is measured to be 4.34 +- 0.45 +- 0.30 and 4.23 +- 0.20 +- 0.21 at c.m. energies of 50 and 52 GeV, respectively. From these values of R and an analysis of the event shapes we deduce a 95%-confidence-level upper limit for the production rate of new heavy charge +(2/3e or -(1/3e quarks to be 0.19 units of R.

P. Mani

Papers

Measurements of R and a search for heavy-quark production in e+e- annihilation at sqrt s =50 and 52 GeV.