Stars are the main factories of element production in the universe through a suite of complex and intertwined physical processes. Such stellar alchemy is driven by multiple nuclear interactions that through eons have transformed the pristine, metal-poor ashes leftover by the Big Bang into a cosmos with 100 distinct chemical species. The products of

This thesis reports the discovery of relativistic stellar explosions outside of the gamma ray band, using optical time domain surveys. It is well known that some massive stars end their lives with the formation of a compact object (a neutron star or black hole) that launches a relativistic jet detectable from earth as a burst of gamma rays. It has long been suspected, however, that gamma ray bursts are only the tip of the iceberg in a broad landscape of relativistic explosions, and so the results presented in this thesis represent a major breakthrough. Highlights of this thesis include: characterization of the first major new class of relativistic explosions in a decade; the discovery of abrupt end-of-life mass-loss in a surprisingly diverse range of stars; and the routine discovery of afterglow emission and several events that may represent baryonically dirty jets or jets viewed slightly off axis. These discoveries necessitated the solution of difficult technical challenges such as the identification of rare and fleeting “needles” in a vast haystack of time-varying phenomena in the night sky, and responding to discoveries within hours to obtain data across the electromagnetic spectrum from X-rays to radio wavelengths.

Bringing together atomic physicists, nuclear physicists, astronomers, and astrophysicists from around the world, Stellar Evolution, Stellar Explosions, and Galactic Chemical Evolution focuses on stellar atmospheres; stellar evolution; stellar explosions, such as novae, supernovae, and x-ray bursters; pregalactic and galactic chemical evolution; the interstellar medium; and atomic and nuclear data for astrophysics. Consisting of invited papers, invited posters, and contributed posters, this volume covers observations, modeling, and atomic and nuclear physics foundations, including data, experiments, and theories, that are essential to understanding these important astrophysical objects and events. It documents a confluence of atomic physics, nuclear physics, and astrophysics and a confluence of data from atomic and nuclear physics experiments from current-generation astronomical instruments-all have helped advance the frontier in our understanding of the universe.

What happens at the end of the life of massive stars? At one time we thought all these stars followed similar evolutionary paths. However, new discoveries have shown that things are not quite that simple. This book focuses on the extreme –the most intense, brilliant and peculiar– of astronomical explosions. It features highly significant observational finds that push the frontiers of astronomy and astrophysics, particularly as before these objects were only predicted in theory. This book is for those who want the latest information and ideas about the most dramatic and unusual explosions detected by current supernova searches. It examines and explains cataclysmic and unusual events in stellar astrophysics and presents them in a non-mathematical but highly detailed way that non-professionals can understand and enjoy.

Targeting advanced students of astronomy and physics, as well as astronomers and physicists contemplating research on supernovae or related fields, David Branch and J. Craig Wheeler offer a modern account of the nature, causes and consequences of supernovae, as well as of issues that remain to be resolved. Owing especially to (1) the appearance of supernova 1987A in the nearby Large Magellanic Cloud, (2) the spectacularly successful use of supernovae as distance indicators for cosmology, (3) the association of some supernovae with the enigmatic cosmic gamma-ray bursts, and (4) the discovery of a class of superluminous supernovae, the pace of supernova research has been increasing sharply. This monograph serves as a broad survey of modern supernova research and a guide to the current literature. The book’s emphasis is on the explosive phases of supernovae. Part 1 is devoted to a survey of the kinds of observations that inform us about supernovae, some basic interpretations of such data, and an overview of the evolution of stars that brings them to an explosive endpoint. Part 2 goes into more detail on core-collapse and superluminous events: which kinds of stars produce them, and how do they do it? Part 3 is concerned with the stellar progenitors and explosion mechanisms of thermonuclear (Type Ia) supernovae. Part 4 is about consequences of supernovae and some applications to astrophysics and cosmology. References are provided in sufficient number to help the reader enter the literature.

“Neutrinos and Explosive Events in the Universe” brought together experts from diverse disciplines to offer a detailed view of the exciting new work in this part of High Energy Astrophysics. Sponsored by NATO as an Advanced Study Institute, and coordinated under the auspices of the International School of Cosmic Ray Astrophysics (14th biennial course), the ASI featured a full program of lectures and discussion in the ambiance of the Ettore Majorana Centre in Erice, Italy, including visits to the local Dirac and Chalonge museum collections as well as a view of the cultural heritage of southern Sicily. Enri- ment presentations on results from the Spitzer Infrared Space Telescope and the Origin of Complexity complemented the program. This course was the best attended in the almost 30 year history of the School with 121 participants from 22 countries. The program provided a rich ex- rience, both introductory and advanced, to fascinating areas of observational Astrophysics Neutrino Astronomy, High Energy Gamma Ray Astronomy, P- ticle Astrophysics and the objects most likely responsible for the signals - plosions and related phenomena, ranging from Supernovae to Black Holes to the Big Bang. Contained in this NATO Science Series volume is a summative formulation of the physics and astrophysics of this newly emerging research area that already has been, and will continue to be, an important contributor to understanding our high energy universe.

b="" The book provides a concise description of the physical processes and mathematical models for explosions and formation of blast waves from explosions. The contents focus on quantitatively determining the energy released in the different types of explosions and the destructive blast waves that are generated. The contribution of flames, detonations and other physical processes to the explosion phenomenon is dealt with in detail. Gaseous and condensed phase explosions are discussed and the yield of explosions with their TNT equivalence is determined. Time scales involved in the explosion process and the scaling procedure are ascertained. Explosions over the ground, in water, and the interaction of explosions with objects are examined. In order to keep the text easily readable, the detailed derivation of the mathematical equations is given in the seven appendices at the end of the book. Case studies of various explosions are investigated and simple problems and their solutions are provided for the different topics to assist the reader in internalizing the explosion process. The book is a useful reference for professionals and academics in aeronautics, mechanical, civil and chemical engineering and for personnel working in explosive manufacture and high-energy materials, armaments, space, defense, and industrial and fire safety.