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Concepts for a Deuterium-Deuterium Fusion Reactor
Concepts for a deuterium-deuterium fusion reactor Roberto Onofrio1, 2 1Dipartimento di Fisica e Astronomia “Galileo Galilei”, Universit`adi Padova, Via Marzolo 8, Padova 35131, Italy 2Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755, USA We revisit the assumption that reactors based on deuterium-deuterium (D-D) fusion processes have to be necessarily developed after the successful completion of experiments and demonstrations for deuterium-tritium (D-T) fusion reactors. Two possible mechanisms for enhancing the reactivity are discussed. Hard tails in the energy distribution of the nuclei, through the so-called κ-distribution, allow to boost the number of energetic nuclei available for fusion reactions. At higher temperatures − − than usually considered in D-T plasmas, vacuum polarization effects from real e+e and µ+µ pairs may provide further speed-up due to their contribution to screening of the Coulomb barrier. Furthermore, the energy collection system can benefit from the absence of the lithium blanket, both in simplicity and compactness. The usual thermal cycle can be bypassed with comparable efficiency levels using hadronic calorimetry and third-generation photovoltaic cells, possibly allowing to extend the use of fusion reactors to broader contexts, most notably maritime transport. I. INTRODUCTION high yield scintillating materials and hadronic calorime- try with third-generation photovoltaic cells. This could lead to energy conversion at an initially nearly compara- It is usually assumed that the first commercial fusion ble efficiency with respect to a thermal cycle, with un- reactors will be based on D-T mixtures, and within this known margins for improvement, and within a compact frame a well-defined path has been paved with the ongo- design. -
Nucleosynthesis
Nucleosynthesis Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang nucleosynthesis. Seventeen minutes later the universe had cooled to a point at which these processes ended, so only the fastest and simplest reactions occurred, leaving our universe containing about 75% hydrogen, 24% helium, and traces of other elements such aslithium and the hydrogen isotope deuterium. The universe still has approximately the same composition today. Heavier nuclei were created from these, by several processes. Stars formed, and began to fuse light elements to heavier ones in their cores, giving off energy in the process, known as stellar nucleosynthesis. Fusion processes create many of the lighter elements up to and including iron and nickel, and these elements are ejected into space (the interstellar medium) when smaller stars shed their outer envelopes and become smaller stars known as white dwarfs. The remains of their ejected mass form theplanetary nebulae observable throughout our galaxy. Supernova nucleosynthesis within exploding stars by fusing carbon and oxygen is responsible for the abundances of elements between magnesium (atomic number 12) and nickel (atomic number 28).[1] Supernova nucleosynthesis is also thought to be responsible for the creation of rarer elements heavier than iron and nickel, in the last few seconds of a type II supernova event. The synthesis of these heavier elements absorbs energy (endothermic process) as they are created, from the energy produced during the supernova explosion. Some of those elements are created from the absorption of multiple neutrons (the r-process) in the period of a few seconds during the explosion. -
Primordial Nucleosynthesis: from Precision Cosmology To
DSF-20/2008, FERMILAB-PUB-08-216-A, IFIC/08-37 Primordial Nucleosynthesis: from precision cosmology to fundamental physics Fabio Iocco a1 , Gianpiero Mangano b, Gennaro Miele b,c, Ofelia Pisanti b, Pasquale D. Serpico d2 aINAF, Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze, Italy bDip. Scienze Fisiche, Universit`adi Napoli Federico II & INFN, Sez. di Napoli, Complesso Univ. Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy c Instituto de F´ısica Corpuscular (CSIC-Universitat de Val`encia), Ed. Institutos de Investigaci´on, Apartado de Correos 22085, E-46071 Val`encia, Spain dCenter for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, IL 60510-0500, USA Abstract We present an up-to-date review of Big Bang Nucleosynthesis (BBN). We discuss the main improvements which have been achieved in the past two decades on the overall theoretical framework, summarize the impact of new experimental results on nuclear reaction rates, and critically re-examine the astrophysical determinations of light nuclei abundances. We report then on how BBN can be used as a powerful test of new physics, constraining a wide range of ideas and theoretical models of fundamental interactions beyond the standard model of strong and electroweak forces and Einstein’s general relativity. Key words: Primordial Nucleosynthesis; Early Universe; Physics Beyond the arXiv:0809.0631v2 [astro-ph] 16 Apr 2009 Standard Model PACS: 98.80.Ft; 26.35.+c; 98.62.Ai Contents 1 Introduction 3 2 Standard Cosmology 6 1 Present address: Institut -
Can Deuterium Formation Be Measured?
CAN DEUTERIUM FORMATION BE MEASURED? Robert K. Soberman∗ and Maurice Dubin† retired (Dated: November 12, 2018) The fundamental PP reaction has never been attempted in the laboratory as theory states it cannot be measured within the human life span. This forms the foundation of stellar nucleosynthesis and the standard solar model. Yet numerous observations including the Sun’s obvious variability argue the theory is flawed and the reaction occurs in times many orders of magnitude shorter than prediction. Considering the consequence to accepted models and controlled fusion, testing is warranted. PACS numbers: 95.30.Cq, 96.60.-j, 25.40.-h There is no record of an attempt to measure the transmutation probability for the fundamental reaction 1H(p, e+,ν)2H. As Bethe and Critchfield [1] predicted a reaction rate of 14(10)9 years no one has been bold enough to test this prediction. Parker and Rolfs [2] wrote “It can be estimated that with a total cross section of 10−47cm2 at Ep(lab) = 1MeV for a proton beam of 1 mA incident on a thick hydrogen target, there would be only one 1H(p, e+,ν)2H reaction in 106 yr.” A similar but numerically discrepant statement appears in Clayton’s classic stellar nucleosynthesis text [3]. As no research team has the patients, resources or longevity to wait out such a prediction it is not surprising that it has never been tested. Such a slow reaction rate was necessary for the standard stellar power model. A much shorter time would cut the lifetime of stars accordingly and a brief reaction time such as seconds would, in that model, cause stars to explode when the reaction conditions were reached. -
Cold Fusion Phenomena May 23-25, 1989 Santa Fe, New Mexico
WORKSHOP ON COLD FUSION PHENOMENA MAY 23-25, 1989 SANTA FE, NEW MEXICO AGENDA Sponsored by Los Alamos National Laboratory and the U.S. Department of Energy TABLE OF CONTENTS Program Committee V Agenda 1-6 Abstracts of Presentations Sessions A - E WORKSHOP CO-CHAIRMAN Prof. Johann Rafelski Department of Physics Dr. Norman Hackerman University of Arizona The Welch Foundation Tucson, AZ Houston, TX Dr. A. John Appleby Dr. J. Robert Schrieffer Center for Electrochemical Systems Director, Institute for and Hydrogen Research Theoretical Physics Texas A&M University University of California College Station, TX Santa Barbara, CA Dr. Anthony L. Turkevich Enrico Fermi Institute TECHNICAL PROGRAM COORDINATOR University of Chicago Chicago, IL Dr. Reed J. Jensen Los Alamos National Laboratory PROGRAM SUPPORT COORDINATOR Mr. David C. Phillips Los Alamos National Laboratory WORKSHOP PROGRAM COMMITTEE Prof. Allen Bard Department of Chemistry University of Texas Austin, TX Dr. Hans Frauenfelder Department of Physics University of Illinois at Urbana-Champaign Urbana, IL Dr. Steven E. Jones Department of Chemistry Brigham Young University Provo, UT Prof. Arthur K. Kerman Director, Laboratory for Nuclear Science MIT Cambridge, MA Prof. Steve Koonin Institute for Theoretical Physics University of California Santa Barbara, CA AGENDA WORKSHOP ON COLD FUSION PHENOMENA May 22-25, 1989 SWEENEY CENTER, SANTA FE, NM MONDAY, MAY 22 Workshop participants arrive in Santa Fe 4:00 - 8:00 Registration and badge issue at EldoradoHotel -Hospitality room available at EldoradoHotel TUESDAY, MAY 23 7:30 - 8:00 Arrival at Sweeney Center 8:00 - 8:30 Late Registration 8:30 - 9:00 Preliminary Remarks Reed J. -
Stellar Evolution
AccessScience from McGraw-Hill Education Page 1 of 19 www.accessscience.com Stellar evolution Contributed by: James B. Kaler Publication year: 2014 The large-scale, systematic, and irreversible changes over time of the structure and composition of a star. Types of stars Dozens of different types of stars populate the Milky Way Galaxy. The most common are main-sequence dwarfs like the Sun that fuse hydrogen into helium within their cores (the core of the Sun occupies about half its mass). Dwarfs run the full gamut of stellar masses, from perhaps as much as 200 solar masses (200 M,⊙) down to the minimum of 0.075 solar mass (beneath which the full proton-proton chain does not operate). They occupy the spectral sequence from class O (maximum effective temperature nearly 50,000 K or 90,000◦F, maximum luminosity 5 × 10,6 solar), through classes B, A, F, G, K, and M, to the new class L (2400 K or 3860◦F and under, typical luminosity below 10,−4 solar). Within the main sequence, they break into two broad groups, those under 1.3 solar masses (class F5), whose luminosities derive from the proton-proton chain, and higher-mass stars that are supported principally by the carbon cycle. Below the end of the main sequence (masses less than 0.075 M,⊙) lie the brown dwarfs that occupy half of class L and all of class T (the latter under 1400 K or 2060◦F). These shine both from gravitational energy and from fusion of their natural deuterium. Their low-mass limit is unknown. -
Direct Measurement of the Neutron
Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 1-9-2020 Stellar Nucleosynthesis: Direct Measurement of the Neutron- Capture Cross Sections of Stable Germanium Isotopes and Design of a Next Generation Ion Trap for the Study of Beta- Delayed Neutron Emission Alexander Laminack Louisiana State University and Agricultural and Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Instrumentation Commons, Nuclear Commons, Physical Processes Commons, and the Stars, Interstellar Medium and the Galaxy Commons Recommended Citation Laminack, Alexander, "Stellar Nucleosynthesis: Direct Measurement of the Neutron-Capture Cross Sections of Stable Germanium Isotopes and Design of a Next Generation Ion Trap for the Study of Beta- Delayed Neutron Emission" (2020). LSU Doctoral Dissertations. 5131. https://digitalcommons.lsu.edu/gradschool_dissertations/5131 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. STELLAR NUCLEOSYNTHESIS: DIRECT MEASUREMENT OF THE NEUTRON-CAPTURE CROSS SECTIONS OF STABLE GERMANIUM ISOTOPES AND DESIGN OF A NEXT GENERATION ION TRAP FOR THE STUDY OF β-DELAYED NEUTRON EMISSION A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Physics and Astronomy by Alexander Laminack B. S., The Unviersity of Alabama, 2015 May 2020 To my wife and son: Kristy Allen Alexander Laminack and Daniel Allen Laminack. -
Primordial Nucleosynthesis in the Precision Cosmology Era the Annual Review of Nuclear and Particle Science Gary Steigman (2007)
Primordial Nucleosynthesis in the Precision Cosmology Era The Annual Review of Nuclear and Particle Science Gary Steigman (2007) Galactic Archeology Seminar Manuel Kramer Universit¨atHeidelberg December 1, 2017 Contents 1 Introduction 2 Fusion of the first nuclides 3 Observations of the relic nuclides 4 Theory vs data 5 Summary Source: CERN Introduction Fusion of the first nuclides Observations of the relic nuclides Theory vs data Summary Fusion of the first nuclides Initial neutron to proton ratio Neutron & Proton equilibrium Once stable hadrons can form from the quark gluon plasma in the very early universe, neutrons and protons are in thermal equilibrium by the weak interactions: − p + e $ n + νe (1) + n + e $ p +ν ¯e Mass of protons is slightly lower than that of the neutrons ni =pi = 1=7 (2) Introduction Fusion of the first nuclides Observations of the relic nuclides Theory vs data Summary Deuterium evolution Deuterium is formed by fusion of a proton and a neutron n + p $ d + γ (3) Significant amounts can only built up when kT . 80 keV −10 The higher the baryon density η10 = 10 (nB=nγ), the higher the interaction rate Introduction Fusion of the first nuclides Observations of the relic nuclides Theory vs data Summary Helium-4 evolution Nucelar fusion processes The starting point for all subsequent fusions is Deuterium Deuterium fusion is a slow reaction Deuterium is immediately converted to 3He and tritium no stable mass-5 nuclides ! bottleneck at 4He Source: https://en.wikipedia.org/ wiki/Big Bang nucleosynthesis Introduction Fusion of -
Modern Physics, the Nature of the Interaction Between Particles Is Carried a Step Further
44.1 Some Properties of Nuclei 1385 are the same, apart from the additional repulsive Coulomb force for the proton– U(r ) (MeV) proton interaction. 40 Evidence for the limited range of nuclear forces comes from scattering experi- n–p system ments and from studies of nuclear binding energies. The short range of the nuclear 20 force is shown in the neutron–proton (n–p) potential energy plot of Figure 44.3a 0 r (fm) obtained by scattering neutrons from a target containing hydrogen. The depth of 1 567432 8 the n–p potential energy well is 40 to 50 MeV, and there is a strong repulsive com- Ϫ20 ponent that prevents the nucleons from approaching much closer than 0.4 fm. Ϫ40 The nuclear force does not affect electrons, enabling energetic electrons to serve as point-like probes of nuclei. The charge independence of the nuclear force also Ϫ60 means that the main difference between the n–p and p–p interactions is that the a p–p potential energy consists of a superposition of nuclear and Coulomb interactions as shown in Figure 44.3b. At distances less than 2 fm, both p–p and n–p potential The difference in the two curves energies are nearly identical, but for distances of 2 fm or greater, the p–p potential is due to the large Coulomb has a positive energy barrier with a maximum at 4 fm. repulsion in the case of the proton–proton interaction. The existence of the nuclear force results in approximately 270 stable nuclei; hundreds of other nuclei have been observed, but they are unstable. -
Nucleosynthetic Isotope Variations of Siderophile and Chalcophile
Reviews in Mineralogy & Geochemistry Vol.81 pp. 107-160, 2016 3 Copyright © Mineralogical Society of America Nucleosynthetic Isotope Variations of Siderophile and Chalcophile Elements in the Solar System Tetsuya Yokoyama Department of Earth and Planetary Sciences Tokyo Institute of Technology Ookayama, Tokyo 152-885 Japan [email protected] Richard J. Walker Department of Geology University of Maryland College Park, MD 20742 USA [email protected] INTRODUCTION Numerous investigations have been devoted to understanding how the materials that contributed to the Solar System formed, were incorporated into the precursor molecular cloud and the protoplanetary disk, and ultimately evolved into the building blocks of planetesimals and planets. Chemical and isotopic analyses of extraterrestrial materials have played a central role in decoding the signatures of individual processes that led to their formation. Among the elements studied, the siderophile and chalcophile elements are crucial for considering a range of formational and evolutionary processes. Consequently, over the past 60 years, considerable effort has been focused on the development of abundance and isotopic analyses of these elements in terrestrial and extraterrestrial materials (e.g., Shirey and Walker 1995; Birck et al. 1997; Reisberg and Meisel 2002; Meisel and Horan 2016, this volume). In this review, we consider nucleosynthetic isotopic variability of siderophile and chalcophile elements in meteorites. Chapter 4 provides a review for siderophile and chalcophile elements in planetary materials in general (Day et al. 2016, this volume). In many cases, such variability is denoted as an “isotopic anomaly”; however, the term can be ambiguous because several pre- and post- Solar System formation processes can lead to variability of isotopic compositions as recorded in meteorites. -
Astronomy General Information
ASTRONOMY GENERAL INFORMATION HERTZSPRUNG-RUSSELL (H-R) DIAGRAMS -A scatter graph of stars showing the relationship between the stars’ absolute magnitude or luminosities versus their spectral types or classifications and effective temperatures. -Can be used to measure distance to a star cluster by comparing apparent magnitude of stars with abs. magnitudes of stars with known distances (AKA model stars). Observed group plotted and then overlapped via shift in vertical direction. Difference in magnitude bridge equals distance modulus. Known as Spectroscopic Parallax. SPECTRA HARVARD SPECTRAL CLASSIFICATION (1-D) -Groups stars by surface atmospheric temp. Used in H-R diag. vs. Luminosity/Abs. Mag. Class* Color Descr. Actual Color Mass (M☉) Radius(R☉) Lumin.(L☉) O Blue Blue B Blue-white Deep B-W 2.1-16 1.8-6.6 25-30,000 A White Blue-white 1.4-2.1 1.4-1.8 5-25 F Yellow-white White 1.04-1.4 1.15-1.4 1.5-5 G Yellow Yellowish-W 0.8-1.04 0.96-1.15 0.6-1.5 K Orange Pale Y-O 0.45-0.8 0.7-0.96 0.08-0.6 M Red Lt. Orange-Red 0.08-0.45 *Very weak stars of classes L, T, and Y are not included. -Classes are further divided by Arabic numerals (0-9), and then even further by half subtypes. The lower the number, the hotter (e.g. A0 is hotter than an A7 star) YERKES/MK SPECTRAL CLASSIFICATION (2-D!) -Groups stars based on both temperature and luminosity based on spectral lines. -
Maximizing Specific Energy by Breeding Deuterium
Maximizing specific energy by breeding deuterium Justin Ball Ecole Polytechnique F´ed´eralede Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland E-mail: [email protected] Abstract. Specific energy (i.e. energy per unit mass) is one of the most fundamental and consequential properties of a fuel source. In this work, a systematic study of measured fusion cross-sections is performed to determine which reactions are potentially feasible and identify the fuel cycle that maximizes specific energy. This reveals that, by using normal hydrogen to breed deuterium via neutron capture, the conventional catalyzed D-D fusion fuel cycle can attain a specific energy greater than anything else. Simply surrounding a catalyzed D-D reactor with water enables deuterium fuel, the dominant stockpile of energy on Earth, to produce as much as 65% more energy. Lastly, the impact on space propulsion is considered, revealing that an effective exhaust velocity exceeding that of deuterium-helium-3 is theoretically possible. 1. Introduction The aim of this work is to investigate the basic question \What fuel source can provide the most energy with the least mass?" For this question, we will look into the near future and assume that the current incremental and steady development of technology will continue. However, we will not postulate any breakthroughs or new physical processes because they cannot be predicted with any certainty. It is already well-known that the answer to our question must involve fusion fuels [1,2], but nothing more precise has been rigorously establishedz. A more precise answer may be useful in the future arXiv:1908.00834v1 [physics.pop-ph] 2 Aug 2019 when the technology required to implement it becomes available.