Experiments at SLC and LEP have made preliminary measurements of the relative partial widths of the c and b quarks. Using D* tagging, DELPHI has found R{sub c}{bar c}{triple bond}/[Gamma]{sub c}{bar c}/[Gamma]{sub hadr.} = 0.162 {plus minus} 0.032 {plus minus} 0.031, in good agreement with the Standard Model value of 0.171. ALEPH has used semileptonic decays of charm to obtain 0.148 {plus minus} 0.044 {sub -0.038}{sup +0.045}. Three experiments have used semileptonic [Beta] decays to measurement R{sub b}{bar b}: R{sub b}{bar b} = 0.23 {plus minus} 0.10 (Mark II), 0.218 {plus minus} 0.010 {plus minus} 0.021 (L3), and 0.220 {plus minus} 0.016 {plus minus} 0.024 (ALEPH). All agree well with the expected value of 0.217. The uncertainty in branching ratios of c and b hadrons is the largest systematic error in all of the results. Future LEP measurements of the branching ratios may reduce the errors. R{sub b}{bar b} will also be measured with different, and possibly lower, systematic errors by Mark II using impact parameter tagging.

The present volume is based on the proceedings of the 6th and 7th INFN ELOISATRON project workshops, held at the Centro di Cultura Scientifica "Et tore Majorana" CCSEM, Erice-Trapani, Sicily, Italy, in the period June 10-27, 1988. The topics of the two workshops were, respectively: - Heavy Flavours: Status and Perspectives, and - Novel Features of High Energy Collisions in 1-100 TeV Region. They were attended by sixty-three physicists. The two workshops were followed by a meeting of the INFN ELOISATRON working group, also held at the CCSEM in the period October 7-15, 1988 in which twenty-five physicists participated. Since there was quite a bit of overlap among speakers, participants and the topics covered at the three meetings, we have decided to issue ajoint proceeding, with the first part entitled: Heavy Flavour Physics, and the second: High Energy Physics with 1-100 Te V Proton Beams. Some of the reports included in this volume have been contributed by the INFN ELOISATRON working group members. The first. part of these proceedings deals mostly with the presentation and inter pretation of results in t.he so-called fiavour physics sector. New results, which have become available in the last three years from experiments involving kaons, charmed and beauty hadrons, and searches for the still missing top quark at the present and fothcoming colliders are topics of major interest. here. The contributions in this part are organized in three categories: Experimental Results, Theoretical Interpretation, and Future Directions.

The lectures collected in this book present a comprehensive review of the current knowledge of heavy-quark physics, from the points of view of both theory and experiment. Heavy Flavour Physics has accomplished enormous progress during the last few years: the last heavy quark has been discovered and the quality of the collected data on the other relatively lighter quarks has dramatically improved. On the theory side, noticeable progress has been reported on new calculations of decay rates based on various techniques, such as QCD sum rules, heavy-quark mass expansion and lattice QCD. The theory of heavy quark production is constantly improving and awaiting new results. Nevertheless there are strong reasons to believe that the Standard Model of High Energy Physics is incomplete. It exhibits very peculiar patterns for which it offers no explanation. The basic constituents of matter are arranged into three seemingly identical generations or families of quarks and leptons, differing merely in their masses. The pattern in the fermion masses, why they are families and why there are three of them is not yet understood. Furthermore it is known that at least within the standard model there is an intimate connection between the replication of families and the gateway of CP violation, in addition, the latter phenomenon is a crucial ingredient in explaining why our universe is made up almost exclusively of matter rather than being more or less matter-antimatter symmetric. How and to what extent can Heavy Flavour Physics impact on these questions? Does it offer novel windows onto New Physics beyond the Standard Model in general and onto new symmetries, such as Supersymmetry in particular? These questions constitute the central theme of this book. The material treated in this publication may serve as reference for the segment of the high-energy community actively engaged in heavy-quark physics.