Download or read book Nucleosynthesis in Early Neutrino Driven Winds written by and published by . This book was released on 2008 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two recent issues related to nucleosynthesis in early proton-rich neutrino winds are investigated. In the first part we investigate the effect of nuclear physics uncertainties on the synthesis of 92Mo and 94Mo. Based on recent experimental results, we find that the proton rich winds of the model investigated here can not be the only source of the solar abundance of 92Mo and 94Mo. In the second part we investigate the nucleosynthesis from neutron rich bubbles and show that they do not contribute to the nucleosynthesis integrated over both neutron and proton-rich bubbles and proton-rich winds.

Download or read book Nucleosynthesis in Neutrino driven Winds written by Lutz Huther and published by . This book was released on 2013 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nucleosynthesis in Early Supernova Winds II written by and published by . This book was released on 2005 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the outstanding unsolved riddles of nuclear astrophysics is the origin of the so called ''p-process'' nuclei from A = 92 to 126. Both the lighter and heavier p-process nuclei are adequately produced in the neon and oxygen shells of ordinary Type II supernovae, but the origin of these intermediate isotopes, especially {sup 92,94}Mo and {sup 96,98}Ru, has long been mysterious. Here we explore the production of these nuclei in the neutrino-driven wind from a young neutron star. We consider such early times that the wind still contains a proton excess because the rates for [nu]{sub e} and positron captures on neutrons are faster than those for the inverse captures on protons. Following a suggestion by Froehlich et al. (2005), they also include the possibility that, in addition to the protons, [alpha]-particles, and heavy seed, a small flux of neutrons is maintained by the reaction p({bar {nu}}{sub e}, e)n. This flux of neutrons is critical in bridging the long waiting points along the path of the rp-process by (n, p) and (n, [gamma]) reactions. Using the unmodified ejecta histories from a recent two-dimensional supernova model by Janka, Buras, and Rampp (2003), they find synthesis of p-rich nuclei up to 1°2Pd. However, if the entropy of these ejecta is increased by a factor of two, the synthesis extends to 12°Te. Still larger increases in entropy, that might reflect the role of magnetic fields or vibrational energy input neglected in the hydrodynamical model, result in the production of numerous r-, s-, and p-process nuclei up to A H"170, even in winds that are proton-rich.

Download or read book Nucleosynthesis in the Neutrino Driven Wind written by Robert D. Hoffman and published by . This book was released on 1996 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nucleosynthesis of Lighter Heavy Elements in Neutrino driven Winds written by Julia Barbara Erika Bliss and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nucleosynthesis in Neutrino Driven Winds from Protoneutron Stars written by Josef Witti and published by . This book was released on 1993 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nucleosynthesis in Neutrino Driven Winds from Protoneutron Stars written by Josef Witti and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Integrated Nucleosynthesis in Neutrino Driven Winds written by and published by . This book was released on 2010 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although they are but a small fraction of the mass ejected in core-collapse supernovae, neutrino-driven winds (NDWs) from nascent proto-neutron stars (PNSs) have the potential to contribute significantly to supernova nucleosynthesis. In previous works, the NDW has been implicated as a possible source of r-process and light p-process isotopes. In this paper we present time-dependent hydrodynamic calculations of nucleosynthesis in the NDW which include accurate weak interaction physics coupled to a full nuclear reaction network. Using two published models of PNS neutrino luminosities, we predict the contribution of the NDW to the integrated nucleosynthetic yield of the entire supernova. For the neutrino luminosity histories considered, no true r-process occurs in the most basic scenario. The wind driven from an older 1.4M{sub {circle_dot}} model for a PNS is moderately neutron-rich at late times however, and produces 87Rb, 88Sr, 89Y, and 9°Zr in near solar proportions relative to oxygen. The wind from a more recently studied 1.27M{sub {circle_dot}} PNS is proton-rich throughout its entire evolution and does not contribute significantly to the abundance of any element. It thus seems very unlikely that the simplest model of the NDW can produce the r-process. At most, it contributes to the production of the N = 50 closed shell elements and some light p-nuclei. In doing so, it may have left a distinctive signature on the abundances in metal poor stars, but the results are sensitive to both uncertain models for the explosion and the masses of the neutron stars involved.

Download or read book Nucleosynthesis in neutrino driven winds from protoneutron stars written by Josef Witti and published by . This book was released on 1993 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nucleosynthesis and Its Implications on Nuclear and Particle Physics written by J. Audouze and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Research Workshop (Fifth Moriond Astrophysics Meeting), Les Arcs, France, March 17-23, 1985

Download or read book Nucleosynthesis in the Hot Convective Bubble in Core Collapse Supernovae written by and published by . This book was released on 2004 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: As an explosion develops in the collapsed core of a massive star, neutrino emission drives convection in a hot bubble of radiation, nucleons, and pairs just outside a proto-neutron star. Shortly thereafter, neutrinos drive a wind-like outflow from the neutron star. In both the convective bubble and the early wind, weak interactions temporarily cause a proton excess (Y{sub e} ≈> 0.50) to develop in the ejected matter. This situation lasts for at least the first second, and the approximately 0.05-0.1 M{sub {circle_dot}} that is ejected has an unusual composition that may be important for nucleosynthesis. Using tracer particles to follow the conditions in a two-dimensional model of a successful supernova explosion calculated by Janka, Buras, and Rampp (2003), they determine the composition of this material. most of it is helium and 56Ni. The rest is relatively rare species produced by the decay of proton-rich isotopes unstable to positron emission. In the absence of pronounced charged-current neutrino capture, nuclear flow will be held up by long-lived waiting point nuclei in the vicinity of 64Ge. The resulting abundance pattern can be modestly rich in a few interesting rare isotopes like 45Sc, 49Ti, and 64Zn. The present calculations imply yields that, when compared with the production of major species in the rest of the supernova, are about those needed to account for the solar abundance of 45Sc and 49Ti. Since the synthesis will be nearly the same in stars of high and low metallicity, the primary production of these species may have discernible signatures in the abundances of low metallicity stars. They also discuss uncertainties in the nuclear physics and early supernova evolution to which abundances of interesting nuclei are sensitive.

Download or read book Handbook of Nuclear Physics written by Isao Tanihata and published by Springer Nature. This book was released on 2023-09-04 with total page 4180 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook is a comprehensive, systematic source of modern nuclear physics. It aims to summarize experimental and theoretical discoveries and an understanding of unstable nuclei and their exotic structures, which were opened up by the development of radioactive ion (RI) beam in the late 1980s. The handbook comprises three major parts. In the first part, the experiments and measured facts are well organized and reviewed. The second part summarizes recognized theories to explain the experimental facts introduced in the first part. Reflecting recent synergistic progress involving both experiment and theory, the chapters both parts are mutually related. The last part focuses on cosmo-nuclear physics—one of the mainstream subjects in modern nuclear physics. Those comprehensive topics are presented concisely. Supported by introductory reviews, all chapters are designed to present their topics in a manner accessible to readers at the graduate level. The book therefore serves as a valuable source for beginners as well, helping them to learn modern nuclear physics.

Download or read book Meteorites and the Early Solar System II written by Dante S. Lauretta and published by University of Arizona Press. This book was released on 2006-07 with total page 992 pages. Available in PDF, EPUB and Kindle. Book excerpt: They range in size from microscopic particles to masses of many tons. The geologic diversity of asteroids and other rocky bodies of the solar system are displayed in the enormous variety of textures and mineralogies observed in meteorites. The composition, chemistry, and mineralogy of primitive meteorites collectively provide evidence for a wide variety of chemical and physical processes. This book synthesizes our current understanding of the early solar system, summarizing information about processes that occurred before its formation. It will be valuable as a textbook for graduate education in planetary science and as a reference for meteoriticists and researchers in allied fields worldwide.

Download or read book Resonant Active sterile Neutrino Conversion and R process Nucleosynthesis in Neutrino heated Supernova Ejecta written by Jonathan Morton Fetter and published by . This book was released on 2000 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On Nucleosynthesis Relevant Conditions in Neutrino driven Supernova Outflows written by Almudena Arcones Segovia and published by . This book was released on 2007 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Current Aspects of Neutrino Physics written by David O. Caldwell and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, written by leading experts of the field, gives an excellent up-to-date overview of modern neutrino physics and is useful for scientists and graduate students alike. The book starts with a history of neutrinos and then develops from the fundamentals to the direct determination of masses and lifetimes. The role of neutrinos in fundamental astrophysical problems is discussed in detail.

Download or read book Astrophysics with Radioactive Isotopes written by Roland Diehl and published by Springer. This book was released on 2018-10-11 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dealing with astrophysics derived from the radiation emitted by radioactive atomic nuclei, this book describes the different methods used to measure cosmic radio-isotopes. It demonstrates how this astronomical window has contributed to the understanding of the sources and the chemical evolution of cosmic gas. Reference materials and explanations are included for students in advanced stages of their education. Nuclear reactions in different sites across the universe lead to the production of stable and unstable nuclei. Their abundances can be measured through different methods, allowing to study the various nuclear processes taking place in cosmic environments. Nucleosynthesis is the cosmic formation of new nuclear species, starting from hydrogen and helium resulting from the big bang origins. Stars create and eject synthesized nuclei during their evolution and explosions. Incorporation of the new interstellar composition into next-generation stars characterises the compositional (chemical) evolution of cosmic gas in and between galaxies. Radioactive species have unique messages about how this occurs. Since the first Edition of this book published in 2011 with the title Astronomy with Radioactivities, long-awaited new direct observations of supernova radioactivity have been made and are now addressed in two updated chapters dealing with supernovae. In this second Edition, the advances of recent years beyond one-dimensional treatments of stellar structure and stellar explosions towards 3-dimensional models have been included, and led to significant re-writings in Chapters 3-5. The sections on the Solar System origins have been re-written to account for new insights into the evolution of giant molecular clouds. The chapter on diffuse radioactivities now also includes material measurements of radioactivities in the current solar system, and their interpretations for recent nucleosynthesis activity in our Galaxy. Significant new results on gamma-rays from positron annihilations have been accounted for in that chapter, and led to new links with nucleosynthesis sources as well as interstellar transport processes. A new chapter now provides a description of interstellar processes often called 'chemical evolution', thus linking the creation of new nuclei to their abundance observations in gas and stars. The experimental / instrumental chapters on nuclear reaction measurements, on gamma-ray telescopes, and pre-solar grain laboratories have been updated. Moreover, new windows of astronomy that have been opened up in recent years have been included in the discussions of the multi-messenger approach that broadens the basis for astrophysical insights.