Small effects that are beyond the current standard models of physics are often signatures for new physics, revealing fields and mass scales far removed from contemporary experimental capabilities. This perspective motivates sensitive searches for rare decays of the kaon. The current status of these searches is reviewed, new results are presented, and progress in the near future is discussed. Opportunities for exciting physics research at a hadron facility are noted. 5 refs., 8 figs., 1 tab.

"Physics at KAON", an international meeting jointly organized by the KFA Jillich and TRI UMF, was held in the Physikzentrum Bad Honnef from June 7 through June 9, 1989. This was one of a series of meetings - the first one in Europe - in which plans for the medium energy physics laboratory KAON were presented and some aspects of the physics at this new facility were discussed. The meeting focussed mainly on the topics of hadron spectroscopy, J{ -meson scattering, strangeness in nuclei, and rare decays. Also presented were some of the research programs at SATURNE and COSY which may well lead to KAON physics in the future. These proceed ings include articles which summarize our current experimental and theoretical knowledge in the various areas, as well as papers which describe lines of research feasible with KAON. The large number of participants - limited, in fact, by the capacity of the Physikzentrum - clearly demonstrates the great interest of the European physics community in the research avenues which will be opened by the high-intensity hadron facilities. March 1990 D. Frekers, D.R. Gill, J. Speth Contents Opening remarks By E. Vogt ...................................................... Sl The TRIUMF kaon factory accelerators By M.K. Craddock ................................................ S3 Experimental facilities By P. Kitching ................................................... S9 Polarized internal targets at KAON By C.A. Miller ................................................... S21 Hyperons in the bound state approach to the Skyrme model.

The physics motivation for searches for very rare kaon decays, either forbidden or suppressed within the Standard Model, is briefly discussed. Simple arguments conclude that such searches probe possible new forces at a 200 TeV mass scale or constitute a precision test of the electroweak model. The examples of such processes are decays of K[sub L][sup O][yields][mu][sup[plus-minus]]e[sup[minus-plus]], K[sup[plus]][yields][pi][sup[plus]][mu][sup[plus]]e[sup[minus]], K[sub L][sup O][yields][mu][sup[minus]], and K[sup[plus]][yields][pi][sup[plus]][nu][bar[nu]]. We present the current experimental status and describe the new efforts to reach sensitivities down to 1 part in 10[sup 12]. The discussion is focused on the experimental program at the Alternating Gradient Synchrotron at Brookhaven National Laboratory, where intense beams make such studies possible.

In 1947, the first of what have come to be known as "strange particles" were detected. As the number and variety of these particles proliferated, physicists began to try to make sense of them. Some seemed to have masses about 900 times that of the electron, and existed in both charged and neutral varieties. These particles are now called kaons (or K mesons), and they have become the subject of some of the most exciting research in particle physics. Kaon Physics at the Turn of the Millennium presents cutting-edge papers by leading theorists and experimentalists that synthesize the current state of the field and suggest promising new directions for the future study of kaons. Topics covered include the history of kaon physics, direct CP violation in kaon decays, time reversal violation, CPT studies, theoretical aspects of kaon physics, rare kaon decays, hyperon physics, charm: CP violation and mixing, the physics of B mesons, and future opportunities for kaon physics in the twenty-first century.

Cities and Their Vital Systems asks basic questions about the longevity, utility, and nature of urban infrastructures; analyzes how they grow, interact, and change; and asks how, when, and at what cost they should be replaced. Among the topics discussed are problems arising from increasing air travel and airport congestion; the adequacy of water supplies and waste treatment; the impact of new technologies on construction; urban real estate values; and the field of "telematics," the combination of computers and telecommunications that makes money machines and national newspapers possible.