On the occasion of the retirement of Ulrich Schwarz, a symposium was held in Groningen in May of 1996, celebrating his contributions to the study of the int- stellar medium, including his work on the high-velocity clouds. The coming together of many specialists in the latter ?eld prompted the idea of compiling a book c- taining their contributions, and summarizing the status of our understanding of the high-velocity cloud phenomenon. This seemed especially worthwhile at the time, since many exciting developments were taking place. After the discovery of some H i clouds with high velocities, about 40 years ago, the subject had been dominated by 21-cm observations of H i emission. Starting in the mid-1980s much progress was being made because of the availability of new instruments, such as large ground-based optical telescopes and UV observatories in space. The connections between the work on high-velocity clouds and other studies of the properties of the (hot) interstellar medium also became clearer.

This is the proceedings of an international conference on the evolution of matter in the Universe, with emphasis on the following topics: big bang nucleosynthesis, cosmic ray nucleosynthesis, stellar nucleosynthesis, galactic chemical and dynamical evolution, and evolution with redshift and cosmic chemical evolution in general.

Since the discovery of the cluster soft excess (CSE) over eight years ago, its properties and origin have been the subject of debate. With the recent launch of new missions such as XMM-Newton and FUSE, we are beginning to answer some of the complex issues regarding the phenomenon. This conference proceedings is an attempt to bring together the latest research results and covers both observational and theoretical work on the CSE and related topics. One of the main topics is the possible relationship between the CSE and the warm-hot intergalactic medium (WHIM), which is believed to harbor 50% of the baryons in the near Universe. New data from both XMM-Newton and FUSE have indicated a possible causal link between the WHIM and CSE. Evidence is based on the apparent detection of O VII emission lines in the soft excess spectrum of the outskirts of several clusters, as well as reports of absorption lines at local and higher redshifts (seen in the spectra of distant sources) as signature of the WHIM. However, while there has been considerable optimism in attributing a substantial fraction of the cluster soft excess flux to WHIM emission, other work shows that, for example, the amount of WHIM material predicted by theoretical simulations falls way short of that necessary to account for the CSE. Other work indicates that at the cores of some cluster this excess emission is so strong, it is impossible to invoke the thermal model without at the same time enlisting radically new physics. Thus alternative interpretations involving non-thermal processes are also reported and being pursued in earnest. Whatever the origin of CSE may turn out to be, results in this book show that it has become beyond reasonable doubt that the phenomenon itself is observationally established. This book reports the scientific progress made by bringing together scientists from a wide range of disciplines. It clearly demonstrates the importance of such meetings and participants if we are to solve this puzzle. This volume is aimed at scientists and graduate students in astronomy who want to learn about the latest results on cluster soft excess observations and theoretical implications.

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This book includes the proceedings of the Workshop held in Madrid, April 1999 to celebrate 2 years of successful operation of the first Spanish small scientific satellite in orbit. It contains discussions about the overall philosophy of small mission programs, the design of the satellite and its payload as well as the most relevant scientific outcome of the mission. Also included are additional contributions to the workshop, which are of importance to Minisat 01 in order to put its results within context. Finally, the future of small missions for space sciences is reviewed together with the main technological challenges for new studies. Out of the technological and scientific results of Minisat 01, the measurement of the EUV airglow spectrum and the flux of some stars in the same range can be highlighted together with the dismiss of the massive neutrino decay theory. The high-energy experiment analyzed the characterization of the radiation environment in LEO and the behaviour of different kind of detectors, as well as the use of coded masks for imaging and the measurement of some specific sources. The book's level is intended for specialists in EUV and Hard X-Ray astrophysicists as well as for engineers and technicians involved in space science experiments and missions.

This volume contains the proceedings of the meeting entitled, "The IGM/Galaxy Connection: The Distribution of Baryons at z = 0. " The meeting was held August 8 -10 at the National Center for Atmospheric Research (NCAR) located in Boulder, Colorado on the foothills of the Rocky Mountains (see conference photo). We organized this meeting because we felt it was time to address the link between galaxies and the intergalactic medium at low redshift. In this vein, we posed several questions to the conference participants: Where are the baryons in the local universe and in what phase do they reside? What signatures of galaxy evolution have been imprinted on the IGM? What percentage of intergalactic gas is left from the galaxy formation process? What does the distribution of baryons at z = 0 tell us about the early universe? The conference was an overwhelming success with lots of friendly interaction and discussion among the participants. At lunch we were treated to splendid views from the NCAR terrace and discussions rang ing from the importance of the LSR, GSR, and LGSR velocity frames to how long the desserts would last with 90 astronomers and the hot Boul der sun. From an inventory of the baryons, to the associations between galaxies and Lya absorbers, to the mechanisms by which galaxies obtain and lose gas, the conference covered many topics. The results of these endeavors are contained in these pages and eloquently summarized by Chris Impey.