Natural Superheavy Nuclei in Astrophysical Data
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Arxiv:Nucl-Th/0402046V1 13 Feb 2004
The Shell Model as Unified View of Nuclear Structure E. Caurier,1, ∗ G. Mart´ınez-Pinedo,2,3, † F. Nowacki,1, ‡ A. Poves,4, § and A. P. Zuker1, ¶ 1Institut de Recherches Subatomiques, IN2P3-CNRS, Universit´eLouis Pasteur, F-67037 Strasbourg, France 2Institut d’Estudis Espacials de Catalunya, Edifici Nexus, Gran Capit`a2, E-08034 Barcelona, Spain 3Instituci´oCatalana de Recerca i Estudis Avan¸cats, Llu´ıs Companys 23, E-08010 Barcelona, Spain 4Departamento de F´ısica Te´orica, Universidad Aut´onoma, Cantoblanco, 28049, Madrid, Spain (Dated: October 23, 2018) The last decade has witnessed both quantitative and qualitative progresses in Shell Model stud- ies, which have resulted in remarkable gains in our understanding of the structure of the nucleus. Indeed, it is now possible to diagonalize matrices in determinantal spaces of dimensionality up to 109 using the Lanczos tridiagonal construction, whose formal and numerical aspects we will analyze. Besides, many new approximation methods have been developed in order to overcome the dimensionality limitations. Furthermore, new effective nucleon-nucleon interactions have been constructed that contain both two and three-body contributions. The former are derived from realistic potentials (i.e., consistent with two nucleon data). The latter incorporate the pure monopole terms necessary to correct the bad saturation and shell-formation properties of the real- istic two-body forces. This combination appears to solve a number of hitherto puzzling problems. In the present review we will concentrate on those results which illustrate the global features of the approach: the universality of the effective interaction and the capacity of the Shell Model to describe simultaneously all the manifestations of the nuclear dynamics either of single particle or collective nature. -
Effects of Acute and Chronic Gamma Irradiation on the Cell Biology and Physiology of Rice Plants
plants Article Effects of Acute and Chronic Gamma Irradiation on the Cell Biology and Physiology of Rice Plants Hong-Il Choi 1,† , Sung Min Han 2,†, Yeong Deuk Jo 1 , Min Jeong Hong 1 , Sang Hoon Kim 1 and Jin-Baek Kim 1,* 1 Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 56212, Korea; [email protected] (H.-I.C.); [email protected] (Y.D.J.); [email protected] (M.J.H.); [email protected] (S.H.K.) 2 Division of Ecological Safety, National Institute of Ecology, Seocheon 33657, Korea; [email protected] * Correspondence: [email protected]; Tel.: +82-63-570-3313 † Both authors contributed equally to this work. Abstract: The response to gamma irradiation varies among plant species and is affected by the total irradiation dose and dose rate. In this study, we examined the immediate and ensuing responses to acute and chronic gamma irradiation in rice (Oryza sativa L.). Rice plants at the tillering stage were exposed to gamma rays for 8 h (acute irradiation) or 10 days (chronic irradiation), with a total irradiation dose of 100, 200, or 300 Gy. Plants exposed to gamma irradiation were then analyzed for DNA damage, oxidative stress indicators including free radical content and lipid peroxidation, radical scavenging, and antioxidant activity. The results showed that all stress indices increased immediately after exposure to both acute and chronic irradiation in a dose-dependent manner, and acute irradiation had a greater effect on plants than chronic irradiation. The photosynthetic efficiency and growth of plants measured at 10, 20, and 30 days post-irradiation decreased in irradiated plants, Citation: Choi, H.-I.; Han, S.M.; Jo, Y.D.; Hong, M.J.; Kim, S.H.; Kim, J.-B. -
Effects of Gamma-Irradiation of Seed Potatoes on Numbers of Stems and Tubers
Netherlands Journal of Agricultural Science 39 (1991) 81-90 Effects of gamma-irradiation of seed potatoes on numbers of stems and tubers A. J. HAVERKORT1, D. I. LANGERAK2 & M. VAN DE WAART1 1 Centre for Agrobiological Research (CABO-DLO), P.O. Box 14, NL 6700 AA Wagenin- gen, Netherlands 2 State Institute for Quality Control of Agricultural Products (RIKILT), P.O. Box 230, NL 6700 AE Wageningen, Netherlands Received 28 november 1990; accepted 8 February 1991 Abstract In field trials with the cultivars Bintje, Jaerla and Spunta, whose seed potatoes were treated with gamma-rays from a ^Co source with doses varying from 0.5 to 27 Gy, tuber yield, har vest index, and number of stems and tubers were determined. A dose of 3 Gy increased the number of tubers by 30 % in Spunta in two out of three trials and by 17 % in one trial in Jaer la, but it did not increase number of tubers in Bintje. Doses of 9 or 10 Gy did not influence the number of tubers nor stems, and decreased harvest index. A dose of 27 Gy yielded off-type plants with reduced yield and number of tubers. Gamma-radiation affected the growth of the apex of the sprout allowing lateral buds or divisions of the affected apex to develop into stems. To achieve larger numbers of tuber-bearing stems, tubers should preferably be irra diated at the start of sprout growth, about 5 months before planting. Keywords: harvest index, gamma irradiation, seed potatoes Introduction Effects of different doses of gamma-rays on potato tubers have been studied exten sively, especially in the 1960s. -
Industrial Applications of Electron Accelerators
Industrial applications of electron accelerators M.R. Cleland Ion Beam Applications, Edgewood, NY 11717, USA Abstract This paper addresses the industrial applications of electron accelerators for modifying the physical, chemical or biological properties of materials and commercial products by treatment with ionizing radiation. Many beneficial effects can be obtained with these methods, which are known as radiation processing. The earliest practical applications occurred during the 1950s, and the business of radiation processing has been expanding since that time. The most prevalent applications are the modification of many different plastic and rubber products and the sterilization of single-use medical devices. Emerging applications are the pasteurization and preservation of foods and the treatment of toxic industrial wastes. Industrial accelerators can now provide electron energies greater than 10 MeV and average beam powers as high as 700 kW. The availability of high-energy, high-power electron beams is stimulating interest in the use of X-rays (bremsstrahlung) as an alternative to gamma rays from radioactive nuclides. 1 Introduction Radiation processing can be defined as the treatment of materials and products with radiation or ionizing energy to change their physical, chemical or biological characteristics, to increase their usefulness and value, or to reduce their impact on the environment. Accelerated electrons, X-rays (bremsstrahlung) emitted by energetic electrons, and gamma rays emitted by radioactive nuclides are suitable energy sources. These are all capable of ejecting atomic electrons, which can then ionize other atoms in a cascade of collisions. So they can produce similar molecular effects. The choice of energy source is usually based on practical considerations, such as absorbed dose, dose uniformity (max/min) ratio, material thickness, density and configuration, processing rate, capital and operating costs. -
Bio-9 a Comparison of Y-Irradiation and Microwave Treatments on the Lipids and Microbiological Pattern of Beef Liver
Seventh Conference of Nuclear Sciences & Applications 6-10 February 2000, Cairo, Egypt Bio-9 A comparison of y-irradiation and microwave treatments on the lipids and microbiological pattern of beef liver Farag, R. S .*, Z. Y. Daw2, Farag , S.A 3 and Safaa A. E. ABD El-Wahab3. / Biochemistry Department, Faculty of Agriculture, Cairo University, Giza - Egypt. 2 Microbiology Department. Faculty of Agriculture. Cairo University, Giza - Egypt. 3 Food irradiation Department, National Center for Radiation Research and Technology, Cairo - Egypt. ABSTRACT EG0100123 The effects of y-irradiation treatments (0, 2.5, 5 and, 10 kGy) and microwaves generated from an oven at low and defrost settings for 0.5 , 1 and 2 min on the chemical composition and microbiological aspects of beef liver samples were studied . The chemical and microbiological analyses were performed on the non-treated and treated beef liver immediately after treatments and during frozen storage (-18°C) for 3 months. The chemical analyses of beef liver Hpids showed that acid, peroxide and TBA(Thiobarbituric acid ) values were slightly increased after irradiation treatments and also during frozen storage (-18°C). On the contrary, iodine value of the treated beef liver was decreased. Irradiation treatments remarkably reduced the total bacterial counts in beef liver. The percent reduction of bacterial load for beef liver exposed to microwaves generated from an oven at defrost mode for 2 min and after 3 months at - 18°C was 62% . The bacterial load for beef liver exposed to y-irradiation at 10 kGy after 3 months at - 18°C was decreased by 98%. Hence, y-irradiation treatment was far better than microwave treatment for inhibiting the multiplication of the associated microorganisms with beef liver. -
Beam–Material Interactions
Beam–Material Interactions N.V. Mokhov1 and F. Cerutti2 1Fermilab, Batavia, IL 60510, USA 2CERN, Geneva, Switzerland Abstract This paper is motivated by the growing importance of better understanding of the phenomena and consequences of high-intensity energetic particle beam interactions with accelerator, generic target, and detector components. It reviews the principal physical processes of fast-particle interactions with matter, effects in materials under irradiation, materials response, related to component lifetime and performance, simulation techniques, and methods of mitigating the impact of radiation on the components and environment in challenging current and future applications. Keywords Particle physics simulation; material irradiation effects; accelerator design. 1 Introduction The next generation of medium- and high-energy accelerators for megawatt proton, electron, and heavy- ion beams moves us into a completely new domain of extreme energy deposition density up to 0.1 MJ/g and power density up to 1 TW/g in beam interactions with matter [1, 2]. The consequences of controlled and uncontrolled impacts of such high-intensity beams on components of accelerators, beamlines, target stations, beam collimators and absorbers, detectors, shielding, and the environment can range from minor to catastrophic. Challenges also arise from the increasing complexity of accelerators and experimental set-ups, as well as from design, engineering, and performance constraints. All these factors put unprecedented requirements on the accuracy of particle production predictions, the capability and reliability of the codes used in planning new accelerator facilities and experiments, the design of machine, target, and collimation systems, new materials and technologies, detectors, and radiation shielding and the minimization of radiation impact on the environment. -
Particle Accelerators and Detectors for Medical Diagnostics and Therapy Arxiv:1601.06820V1 [Physics.Med-Ph] 25 Jan 2016
Particle Accelerators and Detectors for medical Diagnostics and Therapy Habilitationsschrift zur Erlangung der Venia docendi an der Philosophisch-naturwissenschaftlichen Fakult¨at der Universit¨atBern arXiv:1601.06820v1 [physics.med-ph] 25 Jan 2016 vorgelegt von Dr. Saverio Braccini Laboratorium f¨urHochenenergiephysik L'aspetto pi`uentusiasmante della scienza `eche essa incoraggia l'uomo a insistere nei suoi sogni. Guglielmo Marconi Preface This Habilitation is based on selected publications, which represent my major sci- entific contributions as an experimental physicist to the field of particle accelerators and detectors applied to medical diagnostics and therapy. They are reprinted in Part II of this work to be considered for the Habilitation and they cover original achievements and relevant aspects for the present and future of medical applications of particle physics. The text reported in Part I is aimed at putting my scientific work into its con- text and perspective, to comment on recent developments and, in particular, on my contributions to the advances in accelerators and detectors for cancer hadrontherapy and for the production of radioisotopes. Dr. Saverio Braccini Bern, 25.4.2013 i ii Contents Introduction 1 I 5 1 Particle Accelerators and Detectors applied to Medicine 7 2 Particle Accelerators for medical Diagnostics and Therapy 23 2.1 Linacs and Cyclinacs for Hadrontherapy . 23 2.2 The new Bern Cyclotron Laboratory and its Research Beam Line . 39 3 Particle Detectors for medical Applications of Ion Beams 49 3.1 Segmented Ionization Chambers for Beam Monitoring in Hadrontherapy 49 3.2 Proton Radiography with nuclear Emulsion Films . 62 3.3 A Beam Monitor Detector based on doped Silica Fibres . -
14. Structure of Nuclei Particle and Nuclear Physics
14. Structure of Nuclei Particle and Nuclear Physics Dr. Tina Potter Dr. Tina Potter 14. Structure of Nuclei 1 In this section... Magic Numbers The Nuclear Shell Model Excited States Dr. Tina Potter 14. Structure of Nuclei 2 Magic Numbers Magic Numbers = 2; 8; 20; 28; 50; 82; 126... Nuclei with a magic number of Z and/or N are particularly stable, e.g. Binding energy per nucleon is large for magic numbers Doubly magic nuclei are especially stable. Dr. Tina Potter 14. Structure of Nuclei 3 Magic Numbers Other notable behaviour includes Greater abundance of isotopes and isotones for magic numbers e.g. Z = 20 has6 stable isotopes (average=2) Z = 50 has 10 stable isotopes (average=4) Odd A nuclei have small quadrupole moments when magic First excited states for magic nuclei higher than neighbours Large energy release in α, β decay when the daughter nucleus is magic Spontaneous neutron emitters have N = magic + 1 Nuclear radius shows only small change with Z, N at magic numbers. etc... etc... Dr. Tina Potter 14. Structure of Nuclei 4 Magic Numbers Analogy with atomic behaviour as electron shells fill. Atomic case - reminder Electrons move independently in central potential V (r) ∼ 1=r (Coulomb field of nucleus). Shells filled progressively according to Pauli exclusion principle. Chemical properties of an atom defined by valence (unpaired) electrons. Energy levels can be obtained (to first order) by solving Schr¨odinger equation for central potential. 1 E = n = principle quantum number n n2 Shell closure gives noble gas atoms. Are magic nuclei analogous to the noble gas atoms? Dr. -
Low-Energy Nuclear Physics Part 2: Low-Energy Nuclear Physics
BNL-113453-2017-JA White paper on nuclear astrophysics and low-energy nuclear physics Part 2: Low-energy nuclear physics Mark A. Riley, Charlotte Elster, Joe Carlson, Michael P. Carpenter, Richard Casten, Paul Fallon, Alexandra Gade, Carl Gross, Gaute Hagen, Anna C. Hayes, Douglas W. Higinbotham, Calvin R. Howell, Charles J. Horowitz, Kate L. Jones, Filip G. Kondev, Suzanne Lapi, Augusto Macchiavelli, Elizabeth A. McCutchen, Joe Natowitz, Witold Nazarewicz, Thomas Papenbrock, Sanjay Reddy, Martin J. Savage, Guy Savard, Bradley M. Sherrill, Lee G. Sobotka, Mark A. Stoyer, M. Betty Tsang, Kai Vetter, Ingo Wiedenhoever, Alan H. Wuosmaa, Sherry Yennello Submitted to Progress in Particle and Nuclear Physics January 13, 2017 National Nuclear Data Center Brookhaven National Laboratory U.S. Department of Energy USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26) Notice: This manuscript has been authored by employees of Brookhaven Science Associates, LLC under Contract No.DE-SC0012704 with the U.S. Department of Energy. The publisher by accepting the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or any third party’s use or the results of such use of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. -
Present and Future Applications of Industrial Accelerators Craig S
55 Present and Future Applications of Industrial Accelerators Craig S. Nunan Varian Associates, Inc. 56 57 Present and Future Applications of Industrial Accelerators Craig S. Nunan Varian Associates, Inc. Technology transfer - from national laboratories to industry and vice versa implies that concepts, designs, and equipment get transferred. There is also an other mode of transfer which historically has been important - the transfer of ex perienced people. One of the major things that accelerator physics research laboratories have done is to train physicists and engineers in advanced technol ogy. If these people then transfer to industry they can carry with them a level of know-how and creative talent that can be very effective in the on-going applica tion of accelerator-based technology to societal needs. A prime example is Ed Ginzton. Ginzton was a professor of physics at Stanford University and co founder of SLAC, the Stanford Linear Accelerator Center. He was one of the founders of Varian Associates. People from other accelerator laboratories joined Varian over the years. They came from many U.S. and foreign laboratories. Some of the people subsequently left Varian to found other ac celerator companies. A recent example is Bob Hamm, a physicist who trained at Los Alamos Na tional Laboratory, spent two years at Varian, founded AccSys Technology Cor poration, was joined by other people from Los Alamos, and among other things, built the proton linac injector for the proton therapy synchrotron designed and built by Ferrnilab for Lorna Linda University Medical Center. There are other examples of this form of genesis of accelerators in industry. -
Nuclear Physics
Massachusetts Institute of Technology 22.02 INTRODUCTION to APPLIED NUCLEAR PHYSICS Spring 2012 Prof. Paola Cappellaro Nuclear Science and Engineering Department [This page intentionally blank.] 2 Contents 1 Introduction to Nuclear Physics 5 1.1 Basic Concepts ..................................................... 5 1.1.1 Terminology .................................................. 5 1.1.2 Units, dimensions and physical constants .................................. 6 1.1.3 Nuclear Radius ................................................ 6 1.2 Binding energy and Semi-empirical mass formula .................................. 6 1.2.1 Binding energy ................................................. 6 1.2.2 Semi-empirical mass formula ......................................... 7 1.2.3 Line of Stability in the Chart of nuclides ................................... 9 1.3 Radioactive decay ................................................... 11 1.3.1 Alpha decay ................................................... 11 1.3.2 Beta decay ................................................... 13 1.3.3 Gamma decay ................................................. 15 1.3.4 Spontaneous fission ............................................... 15 1.3.5 Branching Ratios ................................................ 15 2 Introduction to Quantum Mechanics 17 2.1 Laws of Quantum Mechanics ............................................. 17 2.2 States, observables and eigenvalues ......................................... 18 2.2.1 Properties of eigenfunctions ......................................... -
Internal and External Exposure Exposure Routes 2.1
Exposure Routes Internal and External Exposure Exposure Routes 2.1 External exposure Internal exposure Body surface From outer space contamination and the sun Inhalation Suspended matters Food and drink consumption From a radiation Lungs generator Radio‐ pharmaceuticals Wound Buildings Ground Radiation coming from outside the body Radiation emitted within the body Radioactive The body is equally exposed to radiation in both cases. materials "Radiation exposure" refers to the situation where the body is in the presence of radiation. There are two types of radiation exposure, "internal exposure" and "external exposure." External exposure means to receive radiation that comes from radioactive materials existing on the ground, suspended in the air, or attached to clothes or the surface of the body (p.25 of Vol. 1, "External Exposure and Skin"). Conversely, internal exposure is caused (i) when a person has a meal and takes in radioactive materials in the food or drink (ingestion); (ii) when a person breathes in radioactive materials in the air (inhalation); (iii) when radioactive materials are absorbed through the skin (percutaneous absorption); (iv) when radioactive materials enter the body from a wound (wound contamination); and (v) when radiopharmaceuticals containing radioactive materials are administered for the purpose of medical treatment. Once radioactive materials enter the body, the body will continue to be exposed to radiation until the radioactive materials are excreted in the urine or feces (biological half-life) or as the radioactivity weakens over time (p.26 of Vol. 1, "Internal Exposure"). The difference between internal exposure and external exposure lies in whether the source that emits radiation is inside or outside the body.