Proceedings of the 14th Winter Workshop held in Snowbird, Utah, January 31-February 7, 1998

th The 13 Winter Workshop on Nuclear Dynamics is the latest installment in a series of workshops that was started in 1978. This series has grown into a tradition, bringing together experimental and theoretical expertise from all areas of the study of nuclear dynamics. As always, the organizers had placed emphasis on the important aspect of cross fertilization between the different energy regimes and wa.ys of viewing a collision of energetic nuclei. This emphasis is reflected in the broad range of topics covered in these proceedings. Phase transitions in nuclear collisions received most of the attention during this workshop, as indicated by the number of contributions on this subject. Many of the questions in connection with these topics remain not settled and will have a huge impact on the physics that can be extracted from experiments at the future Relativistic Heavy Ion Collider. While the experimental program at the AGS is winding down, the NSCL upgrade and RHIC promise a bright future for our field in the USA. In Europe and Asia, major new facilities are under construction as well. The excitement and anticipation in connection with these new opportunities are reflected in these proceedings as well. Wolfgang Bauer Michigan State University Alice Mignerey University of Maryland v PREVIOUS WORKSHOPS The following table contains a list of the dates and locations of the previous Winter Workshops on Nuclear Dynamics as well as the members of the organizing committees. The chairpersons of the conferences are underlined.

th This workshop was the 15 in a series that addresses the subject of the dynamics of nuclear reactions. These workshops are dedicated to the concept that bringing together scientists from diverse areas of nuclear reactions promotes the vibrant exchange of ideas. This workshop hosted presentations from experimentalists and theorists, intermediate energy to ultrarelativistic energies, and final results to recent speculations. Many of these scientists would not normally be exposed to the work done in other subfields. Thus the Winter Workshop on Nuclear Dynamics plays a unique role in information exchange and the stimulation of new ides. The field of nuclear dynamics has a bright future. New accelerators are being planned and completed around the world. New detectors are being constructed. New models and theories are being developed to describe these phenomena. The Winter Workshop on Nuclear Dynamics will continue to promote this lively and compelling field of research. WOLFGANG BAUER AND GARY D. WESTFALL v Previous Workshops The following table contains a list of the dates and locations of the previous Winter Workshops on Nuclear Dynamics as well as the members of the organizing committees. The chairpersons of the conferences are underlined.

The field of nuclear dynamics has evolved tremendously over the course of the 15 years of this workshop series. The workshop presently spans a very broad range of research interests. These include the development of concepts that will form the foundation of research for the quark-gluon plasma as well as current studies of very hot and dense baryonic matter through the measurement of pions, strange particles, dileptons, baryons and antimatter. The investigation of the decay of extremely hot nuclear systems blossomed with the dramatic observation of multifragmentation of heavy systems and detailed studies of the temporal and spatial extent of the system emitting fragments at a wide range of excitation energies. This also includes a continuing search for the liquid-gas phase transition in nuclear matter. An entirely new field of inquiry has begun with the advent of reaction studies with radioactive beams.This international workshop, attended by theorists and experimentalists from 20 institutions and 6 countries, continues to provide the opportunity for cross-fertilization between researchers involved in the broad range of research in nuclear dynamics as well as stimulating the interaction between experimentalists and theorists. The present status of research in the vigorous field of nuclear dynamics is reviewed.

This workshop was established as a forum for experts from different subfields in nuclear dynamics to investigate unifying concepts of nuclear reactions in different beam energy regimes. The proceedings contain an overview of recent experimental and theoretical progress in nuclear dynamics from ultra-subbarrier fusion studies to the physics of the quark-gluon plasma at AGS, CERN, and RHIC energies.