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Sample records for energy nuclear reaction

  1. Nuclear reactions at intermediate energies

    NASA Astrophysics Data System (ADS)

    Shyam, Radhey

    2016-05-01

    In the domain of Nuclear reactions at intermediate energies, the QCD coupling constant αs is large enough (~ 0.3 - 0.5) to render the perturbative calculational techniques inapplicable. In this regime the quarks are confined into colorless hadrons and it is expected that effective field theories of hadron interactions via exchange of hadrons, provide useful tools to describe such reactions. In this contribution we discuss the application of one such theory, the effective Lagrangian model, in describing the hadronic reactions at intermediate energies whose measurements are the focus of a vast international experimental program.

  2. The Science of Low Energy Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Storms, Edmund

    2007-03-01

    The large literature describing the anomalous behavior attributed to cold fusion or low energy nuclear reactions has been critically described in a recently published book. Over 950 publications are evaluated allowing the phenomenon to be understood. A new class of nuclear reactions has been discovered that are able to generate practical energy without significant radiation or radioactivity. Edmund K Storms, The Science of Low Energy Nuclear Reactions, in press (2006). Also see: http://www.lenr-canr.org/StudentsGuide.htm .

  3. Low Energy Nuclear Reactions: 2007 Update

    NASA Astrophysics Data System (ADS)

    Krivit, Steven B.

    2007-03-01

    This paper presents an overview of low energy nuclear reactions, a subset of the field of condensed matter nuclear science. Condensed matter nuclear science studies nuclear effects in and/or on condensed matter, including low energy nuclear reactions, an entirely new branch of science that gained widespread attention and notoriety beginning in 1989 with the announcement of a previously unrecognized source of energy by Martin Fleischmann and Stanley Pons that came to be known as cold fusion. Two branches of LENR are recognized. The first includes a set of reactions like those observed by Fleischmann and Pons that use palladium and deuterium and yield excess heat and helium-4. Numerous mechanisms have been proposed to explain these reactions, however there is no consensus for, or general acceptance of, any of the theories. The claim of fusion is still considered speculative and, as such, is not an ideal term for this work. The other branch is a wide assortment of nuclear reactions that may occur with either hydrogen or deuterium. Anomalous nuclear transmutations are reported that involve light as well as heavy elements. The significant questions that face this field of research are: 1) Are LENRs a genuine nuclear reaction? 2) If so, is there a release of excess energy? 3) If there is, is the energy release cost-effective?

  4. Nuclear phenomena in low-energy nuclear reaction research.

    PubMed

    Krivit, Steven B

    2013-09-01

    This is a comment on Storms E (2010) Status of Cold Fusion, Naturwissenschaften 97:861-881. This comment provides the following remarks to other nuclear phenomena observed in low-energy nuclear reactions aside from helium-4 make significant contributions to the overall energy balance; and normal hydrogen, not just heavy hydrogen, produces excess heat.

  5. Low Energy Nuclear Reaction Products at Surfaces

    NASA Astrophysics Data System (ADS)

    Nagel, David J.

    2008-03-01

    This paper examines the evidence for LENR occurring on or very near to the surface of materials. Several types of experimental indications for LENR surface reactions have been reported and will be reviewed. LENR result in two types of products, energy and the appearance of new elements. The level of instantaneous power production can be written as the product of four factors: (1) the total area of the surface on which the reactions can occur, (2) the fraction of the area that is active at any time, (3) the reaction rate, that is, the number of reactions per unit active area per second, and (4) the energy produced per reaction. Each of these factors, and their limits, are reviewed. A graphical means of relating these four factors over their wide variations has been devised. The instantaneous generation of atoms of new elements can also be written as the product of the first three factors and the new elemental mass produced per reaction. Again, a graphical means of presenting the factors and their results over many orders of magnitude has been developed.

  6. Overview of Light Hydrogen-Based Low Energy Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Miley, George H.; Shrestha, Prajakti J.

    This paper reviews light water and hydrogen-based low-energy nuclear reactions (LENRs) including the different methodologies used to study these reactions and the results obtained. Reports of excess heat production, transmutation reactions, and nuclear radiation emission are cited. An aim of this review is to present a summary of the present status of light water LENR research and provide some insight into where this research is heading.

  7. The nuclear structure and low-energy reactions (NSLER) collaboration

    NASA Astrophysics Data System (ADS)

    Dean, D. J.; NSLER Collaboration

    2006-09-01

    The long-term vision of the Nuclear Structure and Low-Energy Reactions (NSLER) collaboration is to arrive at a comprehensive and unified description of nuclei and their reactions that is grounded in the interactions between the constituent nucleons. For this purpose, we will develop a universal energy density functional for nuclei and replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that will deliver maximum predictive power with minimal uncertainties that are well quantified. Nuclear structure and reactions play an essential role in the science to be investigated at rare isotope facilities, and in nuclear physics applications to the Science-Based Stockpile Stewardship Program, next-generation reactors, and threat reduction. We anticipate an expansion of the computational techniques and methods we currently employ, and developments of new treatments, to take advantage of petascale architectures and demonstrate the capability of the leadership class machines to deliver new science heretofore impossible.

  8. Nuclear reactions induced by high-energy alpha particles

    NASA Technical Reports Server (NTRS)

    Shen, B. S. P.

    1974-01-01

    Experimental and theoretical studies of nuclear reactions induced by high energy protons and heavier ions are included. Fundamental data needed in the shielding, dosimetry, and radiobiology of high energy particles produced by accelerators were generated, along with data on cosmic ray interaction with matter. The mechanism of high energy nucleon-nucleus reactions is also examined, especially for light target nuclei of mass number comparable to that of biological tissue.

  9. Low-energy nuclear reaction studies with RI beams in nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Kubono, S.; Teranishi, T.; Kato, S.

    2003-07-01

    After a brief discussion on the recent development in nuclear astrophysics, two reaction studies of typical astrophysical reactions at low energies where nuclear reactions play the main contributions to the nucleosynthesis in the universe, are discussed. One is the proton capture reaction, 11C(p, γ)12N, studied by the direct method using a 11C beam produced with a new low-energy RIB separator CRIB at CNS, Japan. The second one is the 13C(α, n)16O rearrangement reaction, which is believed to be the main neutron source for the s-process at low temperatures, investigated by an indirect method using the direct α-transfer reaction 13C(6Li, d)17O. Detailed investigations are suggested on the nuclear reactions relevant.

  10. Resonant Electromagnetic Interaction in Low Energy Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Chubb, Scott

    2008-03-01

    Basic ideas about how resonant electromagnetic interaction (EMI) can take place in finite solids are reviewed. These ideas not only provide a basis for conventional, electron energy band theory (which explains charge and heat transport in solids), but they also explain how through finite size effects, it is possible to create many of the kinds of effects envisioned by Giuliano Preparata. The underlying formalism predicts that the orientation of the external fields in the SPAWAR protocolootnotetextKrivit, Steven B., New Energy Times, 2007, issue 21, item 10. http://newenergytimes.com/news/2007/NET21.htm^,ootnotetextSzpak, S.; Mosier-Boss, P.A.; Gordon, F.E. Further evidence of nuclear reactions in the Pd lattice: emission of charged particles. Naturwissenschaften 94,511(2007)..has direct bearing on the emission of high-energy particles. Resonant EMI also implies that nano-scale solids, of a particular size, provide an optimal environment for initiating Low Energy Nuclear Reactions (LENR) in the PdD system.

  11. Rydberg phases of Hydrogen and low energy nuclear reactions

    NASA Astrophysics Data System (ADS)

    Olafsson, Sveinn; Holmlid, Leif

    2016-03-01

    For over the last 26 years the science of cold fusion/LENR has been researched around the world with slow pace of progress. Modest quantity of excess heat and signatures of nuclear transmutation and helium production have been confirmed in experiments and theoretical work has only resulted in a large flora of inadequate theoretical scenarios. Here we review current state of research in Rydberg matter of Hydrogen that is showing strong signature of nuclear processes. In the presentation experimental behavior of Rydberg matter of hydrogen is described. An extensive collaboration effort of surface physics, catalysis, atomic physics, solid state physics, nuclear physics and quantum information is need to tackle the surprising experimental results that have so far been obtained. Rydberg matter of Hydrogen is the only known state of matter that is able to bring huge collection of protons to so short distances and for so long time that tunneling becomes a reasonable process for making low energy nuclear reactions. Nuclear quantum entanglement can also become realistic process at theses conditions.

  12. New Mechanism of Low Energy Nuclear Reactions Using Superlow

    NASA Astrophysics Data System (ADS)

    Gareev, F. A.; Zhidkova, I. E.

    2006-03-01

    We proposed a new mechanism of LENR (low energy nuclear reactions) cooperative processes in the whole system - nuclei+atoms+condensed matter can occur at smaller threshold than the corresponding ones assoiciated with free constituents. The cooperative processes can be induced and enhanced by (``superlow energy'') external fields. The excess heat is the emission of internal energy, and transmutations from LENR are the result of redistribution of the internal energy of the whole system. A review of possible stimulation mechanisms of LENR is presented. We have concluded that transmutation of nuclei at low energies and excess heat are possible in the framework of the known fundamental physical laws: The universal resonance synchronization principle, and based on it, different enhancement mechanisms of reaction rates are responsible for these processes. The excitation and ionization of atoms may play the role of a trigger for LENR. F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/0511092 v1 30 Nov 2005. F.A. Gareev, In: FPB-98, Novosibirsk, June 1998, p.92; F.A.Gareev, G.F. Gareeva, in: Novosibirsk, July 2000, p.161. F.A. Gareev, I.E. Zhidkova and Yu.L. Ratis, Preprint JINR P4-2004-68, Dubna, 2004. F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/0505021 9 May 2005.

  13. Screening in Low Energy Nuclear Reactions of Importance to Astrophysics

    NASA Astrophysics Data System (ADS)

    Miley, George H.; Hora, Heinz; Luo, Nie

    2004-05-01

    Recent experiments in the LUNAR (Laboratory for Underground Nuclear Astrophysics) project have shown anonymously high electron screening may occur during acceleration driven low energy (<400 kV) ion bombardment of solid targets [1]. These effects become particularly important for E/ Ue < 100 (here E= ion energy and Ue = electron-screening potential energy). Thus these effects become significant for the understanding of reactions involved in nucleosynthesis of the elements and the interpretation of astrophysical data [1]. Another example of the behavior is the surprising threshold behavior near 18 keV for deuterons stopping in 3He gas at energies below the Bragg peak [2]. As pointed out in ref [1], the theoretical explanation for these effects is still under debate. Several researchers have proposed variations of the Trojan Horse Method (THM) to explain these effects [3]. In this paper, we propose an alternate mechanism associated with electron charge accumulation around the target atoms arising from the solid-state structure of the host. This concept will be explained in terms of density functional calculations of charge density profiles in a target undergoing ion dynamic effects [4]. REFERENCES [1] F. Strieder, et al., Naturwissenschaften (2000)88:461-467 [2] A. Formicola, et al., (2000) Eur Phys J. A 8:443-446 [3] S. Typel and H H Wolter, (2000) Few-Body System 29:75-93 [4] G. Miley and H. Hora, (2000) Nuclear Reactions in Solids, APS mtg. Lansing, MI [5] G. Miley, A. Lipson, N. Luo, and H. Hora, (2003) IEEE NSS/MIC Conf., Portland, OR

  14. Nuclear structure and reaction studies at medium energies

    SciTech Connect

    Hoffmann, G.W.; Ray, R.L.

    1990-10-01

    This document constitutes the (1988--1991) technical progress report for the ongoing medium energy physics research program supported by the US Department of Energy through special Research Grant FG05-88ER40444. The experiments discussed are conducted at the Los Alamos National Laboratory's (LANL) Clinton P. Anderson Meson Physics Facility (LAMPF), the Alternating Gradient Synchrotron (AGS) facility of the Brookhaven National Laboratory (BNL), and at the Fermi National Accelerator Laboratory (FNAL). The overall motivation for the work discussed in this document is driven by three main objectives: (1) provide hadron-nucleon and hadron-nucleus scattering data which serve to facilitate the study of effective two-body interactions, test (and possibly determine) nuclear structure, and help study reaction mechanisms and dynamics;(2) provide unique, first-of-a-kind exploratory'' hadron-nucleus scattering data in the hope that such data will lead to discovery of new phenomena and new physics; and (3) perform precision tests of fundamental interactions, such as rare decay searches, whose observation would imply fundamental new physics.

  15. Deuterium cluster model for low energy nuclear reactions (LENR)

    NASA Astrophysics Data System (ADS)

    Miley, George; Hora, Heinrich

    2007-11-01

    For studying the possible reactions of high density deuterons on the background of a degenerate electron gas, a summary of experimental observations resulted in the possibility of reactions in pm distance and more than ksec duration similar to the K-shell electron capture [1]. The essential reason was the screening of the deuterons by a factor of 14 based on the observations. Using the bosonic properties for a cluster formation of the deuterons and a model of compound nuclear reactions [2], the measured distribution of the resulting nuclei may be explained as known from the Maruhn-Greiner theory for fission. The local maximum of the distribution at the main minimum indicates the excited states of the compound nuclei during their intermediary state. This measured local maximum may be an independent proof for the deuteron clusters at LENR. [1] H. Hora, G.H. Miley et al. Physics Letters A175, 138 (1993) [2] H. Hora and G.H. Miley, APS March Meeting 2007, Program p. 116

  16. Study of Nuclear Structure of 13C and 20Ne by Low Energy Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Lombardo, I.; Campajola, L.; Dell'Aquila, D.; La Commara, M.; Ordine, A.; Rosato, E.; Spadaccini, G.; Vigilante, M.

    2014-12-01

    We report some recent experimental results on the spectroscopy of 13C and 20Ne nuclei by means of low energy nuclear reactions carried out with high resolution electrostatic accelerators. In the case of 13C we investigated the possible existence of a-cluster states above the a emission threshold by means of low energy elastic resonant scattering α+9Be in direct kinematics. Excitation functions show the presence of various resonances that have been reproduced by R-matrix fit. We studied also the structure of 20Ne by means of the 19F(p,α0) reaction at sub-barrier energies. The spectroscopy of 20Ne excited states in the region Ex ≈ 13.5-14.0 MeV can be probed by analyzing experimental angular distributions and excitation functions. This reaction plays an important role also in the CNOF cycle and is an important ingredient to describe hydrogen-induced destruction of fluorine in massive stars. For this reason we investigated the trend of S-factor, that has been compared with results previously reported in the literature.

  17. Uncovering Special Nuclear Materials by Low-energy Nuclear Reaction Imaging

    DOE PAGES

    Rose, P. B.; Erickson, A. S.; Mayer, M.; Nattress, J.; Jovanovic, I.

    2016-04-18

    Weapons-grade uranium and plutonium could be used as nuclear explosives with extreme destructive potential. The problem of their detection, especially in standard cargo containers during transit, has been described as “searching for a needle in a haystack” because of the inherently low rate of spontaneous emission of characteristic penetrating radiation and the ease of its shielding. Currently, the only practical approach for uncovering well-shielded special nuclear materials is by use of active interrogation using an external radiation source. However, the similarity of these materials to shielding and the required radiation doses that may exceed regulatory limits prevent this method frommore » being widely used in practice. We introduce a low-dose active detection technique, referred to as low-energy nuclear reaction imaging, which exploits the physics of interactions of multi-MeV monoenergetic photons and neutrons to simultaneously measure the material’s areal density and effective atomic number, while confirming the presence of fissionable materials by observing the beta-delayed neutron emission. For the first time, we demonstrate identification and imaging of uranium with this novel technique using a simple yet robust source, setting the stage for its wide adoption in security applications.« less

  18. Uncovering Special Nuclear Materials by Low-energy Nuclear Reaction Imaging.

    PubMed

    Rose, P B; Erickson, A S; Mayer, M; Nattress, J; Jovanovic, I

    2016-04-18

    Weapons-grade uranium and plutonium could be used as nuclear explosives with extreme destructive potential. The problem of their detection, especially in standard cargo containers during transit, has been described as "searching for a needle in a haystack" because of the inherently low rate of spontaneous emission of characteristic penetrating radiation and the ease of its shielding. Currently, the only practical approach for uncovering well-shielded special nuclear materials is by use of active interrogation using an external radiation source. However, the similarity of these materials to shielding and the required radiation doses that may exceed regulatory limits prevent this method from being widely used in practice. We introduce a low-dose active detection technique, referred to as low-energy nuclear reaction imaging, which exploits the physics of interactions of multi-MeV monoenergetic photons and neutrons to simultaneously measure the material's areal density and effective atomic number, while confirming the presence of fissionable materials by observing the beta-delayed neutron emission. For the first time, we demonstrate identification and imaging of uranium with this novel technique using a simple yet robust source, setting the stage for its wide adoption in security applications.

  19. Uncovering Special Nuclear Materials by Low-energy Nuclear Reaction Imaging.

    PubMed

    Rose, P B; Erickson, A S; Mayer, M; Nattress, J; Jovanovic, I

    2016-01-01

    Weapons-grade uranium and plutonium could be used as nuclear explosives with extreme destructive potential. The problem of their detection, especially in standard cargo containers during transit, has been described as "searching for a needle in a haystack" because of the inherently low rate of spontaneous emission of characteristic penetrating radiation and the ease of its shielding. Currently, the only practical approach for uncovering well-shielded special nuclear materials is by use of active interrogation using an external radiation source. However, the similarity of these materials to shielding and the required radiation doses that may exceed regulatory limits prevent this method from being widely used in practice. We introduce a low-dose active detection technique, referred to as low-energy nuclear reaction imaging, which exploits the physics of interactions of multi-MeV monoenergetic photons and neutrons to simultaneously measure the material's areal density and effective atomic number, while confirming the presence of fissionable materials by observing the beta-delayed neutron emission. For the first time, we demonstrate identification and imaging of uranium with this novel technique using a simple yet robust source, setting the stage for its wide adoption in security applications. PMID:27087555

  20. Uncovering Special Nuclear Materials by Low-energy Nuclear Reaction Imaging

    NASA Astrophysics Data System (ADS)

    Rose, P. B.; Erickson, A. S.; Mayer, M.; Nattress, J.; Jovanovic, I.

    2016-04-01

    Weapons-grade uranium and plutonium could be used as nuclear explosives with extreme destructive potential. The problem of their detection, especially in standard cargo containers during transit, has been described as “searching for a needle in a haystack” because of the inherently low rate of spontaneous emission of characteristic penetrating radiation and the ease of its shielding. Currently, the only practical approach for uncovering well-shielded special nuclear materials is by use of active interrogation using an external radiation source. However, the similarity of these materials to shielding and the required radiation doses that may exceed regulatory limits prevent this method from being widely used in practice. We introduce a low-dose active detection technique, referred to as low-energy nuclear reaction imaging, which exploits the physics of interactions of multi-MeV monoenergetic photons and neutrons to simultaneously measure the material’s areal density and effective atomic number, while confirming the presence of fissionable materials by observing the beta-delayed neutron emission. For the first time, we demonstrate identification and imaging of uranium with this novel technique using a simple yet robust source, setting the stage for its wide adoption in security applications.

  1. Uncovering Special Nuclear Materials by Low-energy Nuclear Reaction Imaging

    PubMed Central

    Rose, P. B.; Erickson, A. S.; Mayer, M.; Nattress, J.; Jovanovic, I.

    2016-01-01

    Weapons-grade uranium and plutonium could be used as nuclear explosives with extreme destructive potential. The problem of their detection, especially in standard cargo containers during transit, has been described as “searching for a needle in a haystack” because of the inherently low rate of spontaneous emission of characteristic penetrating radiation and the ease of its shielding. Currently, the only practical approach for uncovering well-shielded special nuclear materials is by use of active interrogation using an external radiation source. However, the similarity of these materials to shielding and the required radiation doses that may exceed regulatory limits prevent this method from being widely used in practice. We introduce a low-dose active detection technique, referred to as low-energy nuclear reaction imaging, which exploits the physics of interactions of multi-MeV monoenergetic photons and neutrons to simultaneously measure the material’s areal density and effective atomic number, while confirming the presence of fissionable materials by observing the beta-delayed neutron emission. For the first time, we demonstrate identification and imaging of uranium with this novel technique using a simple yet robust source, setting the stage for its wide adoption in security applications. PMID:27087555

  2. Proton Reaction Data Library for Nuclear Activation (Medium Energy Nuclear Data Library.)

    2002-03-01

    Version 00 GROUPXS does file handling and processing of the double-differential continuum-emission cross sections stored in the new MF6 format of ENDF/VI. It treats the energy-angle data that are supposed to be represented by a Legendre-polynomial expansion in the center-of-mass system and can do the following: (1) Conversion of MF6 data from center-of-mass system to the laboratory system, with the possibility to continue the calculation with the options (2), (3), and (4). (2) Conversion ofmore » Legendre-polynomial representation into point-wise angular data, in MF6 format. (3) Conversion of data from MF6 into MF4 + MF5 (ENDF-V). (4) Calculation of group constants, scattering matrices and transfer matrices for arbitrary group structures with a fusion micro-flux weighting spectrum (PN-approximation). The code treats only continuum reaction types that are stored in the MF6 format with the restrictions as specified for the European Fusion File (EFF1). These restrictions are not inconvenient for the purpose of fusion neutronics calculations and they facilitate relatively simple processing . This neutron reaction data library can be used for nuclear activation and transmutation applications at energies up to 100 MeV.« less

  3. Low-Energy Nuclear Reactions of Protons in Host Metals at Picometre Distance

    SciTech Connect

    Heinrich Hora; George H. Miley; Jak C. Kelly

    2000-11-12

    A review is given for the explanation of the measurements of Miley et al. of a fully reproducible generation of nuclei of the whole periodic table by protons in host metals during a several-weeks reaction. Similar low-energy nuclear reactions (LENR) were observed by other groups. The fact that the heavy nuclides are not due to pollution can be seen from the fact that such very rare elements as thulium and terbium were detected by unique K-shell X-ray spectra. The nuclear reaction energy goes into the heavy nuclei as measured from much bigger traces in CR39 than from alphas. The fact that any reaction of the protons results in stable daughter nuclei is confirmed by the fact that the highest energy gain is resulting with stable reaction products. This has been explained in Ref. 2, and the energy gain for the heavy element generation by a compound reaction was discussed. The explanation is based on the model of the authors from 1989 to assume free motion of the protons contrary to localized crystalline states. A relation of the reaction time U on distance d of the reacting nuclei by a power law with an exponent 34.8 was derived. Based on few reproducible D-D reactions, a reaction time near the range of megaseconds and a reaction distance of nanometers was concluded. A splendid confirmation of the picometre-megasecond reactions was achieved by Li et al. from his direct quantum mechanical calculations of the hot fusion D-T reactions based on a one-step selective resonance tunneling model. Li et al. were able for the first time to derive the cross sections of the hot fusion. Li's application to picometre distance showed megasecond reaction times with no neutron or gamma emission. Because of the imaginary part in the Schroedinger potential, the problem of the level width is reduced by damping.

  4. Nuclear Reaction Data Centers

    SciTech Connect

    McLane, V.; Nordborg, C.; Lemmel, H.D.; Manokhin, V.N.

    1988-01-01

    The cooperating Nuclear Reaction Data Centers are involved in the compilation and exchange of nuclear reaction data for incident neutrons, charged particles and photons. Individual centers may also have services in other areas, e.g., evaluated data, nuclear structure and decay data, reactor physics, nuclear safety; some of this information may also be exchanged between interested centers. 20 refs., 1 tab.

  5. Resonant Interaction, Approximate Symmetry, and Electromagnetic Interaction (EMI) in Low Energy Nuclear Reactions (LENR)

    NASA Astrophysics Data System (ADS)

    Chubb, Scott

    2007-03-01

    Only recently (talk by P.A. Mosier-Boss et al, in this session) has it become possible to trigger high energy particle emission and Excess Heat, on demand, in LENR involving PdD. Also, most nuclear physicists are bothered by the fact that the dominant reaction appears to be related to the least common deuteron(d) fusion reaction,d+d ->α+γ. A clear consensus about the underlying effect has also been illusive. One reason for this involves confusion about the approximate (SU2) symmetry: The fact that all d-d fusion reactions conserve isospin has been widely assumed to mean the dynamics is driven by the strong force interaction (SFI), NOT EMI. Thus, most nuclear physicists assume: 1. EMI is static; 2. Dominant reactions have smallest changes in incident kinetic energy (T); and (because of 2), d+d ->α+γ is suppressed. But this assumes a stronger form of SU2 symmetry than is present; d+d ->α+γ reactions are suppressed not because of large changes in T but because the interaction potential involves EMI, is dynamic (not static), the SFI is static, and because the two incident deuterons must have approximate Bose Exchange symmetry and vanishing spin. A generalization of this idea involves a resonant form of reaction, similar to the de-excitation of an atom. These and related (broken gauge) symmetry EMI effects on LENR are discussed.

  6. Nuclear-Pumped Lasers. [efficient conversion of energy liberated in nuclear reactions to coherent radiation

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The state of the art in nuclear pumped lasers is reviewed. Nuclear pumped laser modeling, nuclear volume and foil excitation of laser plasmas, proton beam simulations, nuclear flashlamp excitation, and reactor laser systems studies are covered.

  7. Low Energy Nuclear Reaction Aircraft- 2013 ARMD Seedling Fund Phase I Project

    NASA Technical Reports Server (NTRS)

    Wells, Douglas P.; McDonald, Robert; Campbell, Robbie; Chase, Adam; Daniel, Jason; Darling, Michael; Green, Clayton; MacGregor, Collin; Sudak, Peter; Sykes, Harrison; Waddington, Michael; Fredericks, William J.; Lepsch, Roger A.; Martin, John G.; Moore, Mark D.; Zawodny, Joseph M.; Felder, James L.; Snyder, Christopher A.

    2014-01-01

    This report serves as the final written documentation for the Aeronautic Research Mission Directorate (ARMD) Seedling Fund's Low Energy Nuclear Reaction (LENR) Aircraft Phase I project. The findings presented include propulsion system concepts, synergistic missions, and aircraft concepts. LENR is a form of nuclear energy that potentially has over 4,000 times the energy density of chemical energy sources. It is not expected to have any harmful emissions or radiation which makes it extremely appealing. There is a lot of interest in LENR, but there are no proven theories. This report does not explore the feasibility of LENR. Instead, it assumes that a working system is available. A design space exploration shows that LENR can enable long range and high speed missions. Six propulsion concepts, six missions, and four aircraft concepts are presented. This report also includes discussion of several issues and concerns that were uncovered during the study and potential research areas to infuse LENR aircraft into NASA's aeronautics research.

  8. Use of Helium Production to Screen Glow Discharges for Low Energy Nuclear Reactions (LENR)

    NASA Astrophysics Data System (ADS)

    Passell, Thomas O.

    2011-03-01

    My working hypothesis of the conditions required to observe low energy nuclear reactions (LENR) follows: 1) High fluxes of deuterium atoms through interfaces of grains of metals that readily accommodate movement of hydrogen atoms interstitially is the driving variable that produces the widely observed episodes of excess heat above the total of all input energy. 2) This deuterium atom flux has been most often achieved at high electrochemical current densities on highly deuterium-loaded palladium cathodes but is clearly possible in other experimental arrangements in which the metal is interfacing gaseous deuterium, as in an electrical glow discharge. 3) Since the excess heat episodes must be producing the product(s) of some nuclear fusion reaction(s) screening of options may be easier with measurement of those ``ashes'' than the observance of the excess heat. 4) All but a few of the exothermic fusion reactions known among the first 5 elements produce He-4. Hence helium-4 appearance in an experiment may be the most efficient indicator of some fusion reaction without commitment on which reaction is occurring. This set of hypotheses led me to produce a series of sealed tubes of wire electrodes of metals known to absorb hydrogen and operate them for 100 days at the 1 watt power level using deuterium gas pressures of ~ 100 torr powered by 40 Khz AC power supplies. Observation of helium will be by measurement of helium optical emission lines through the glass envelope surrounding the discharge. The results of the first 18 months of this effort will be described.

  9. The use of low energy, ion induced nuclear reactions for proton radiotherapy applications

    SciTech Connect

    Horn, K.M.; Doyle, B.; Segal, M.N.; Hamm, R.W.; Adler, R.J.; Glatstein, E.

    1995-04-01

    Medical radiotherapy has traditionally relied upon the use of external photon beams and internally implanted radioisotopes as the chief means of irradiating tumors. However, advances in accelerator technology and the exploitation of novel means of producing radiation may provide useful alternatives to some current modes of medical radiation delivery with reduced total dose to surrounding healthy tissue, reduced expense, or increased treatment accessibility. This paper will briefly overview currently established modes of radiation therapy, techniques still considered experimental but in clinical use, innovative concepts under study that may enable new forms of treatment or enhance existing ones. The potential role of low energy, ion-induced nuclear reactions in radiotherapy applications is examined specifically for the 650 keV d({sup 3}He,p){sup 4}He nuclear reaction. This examination will describe the basic physics associated with this reaction`s production of 17.4 MeV protons and the processes used to fabricate the necessary materials used in the technique. Calculations of the delivered radiation dose, heat generation, and required exposure times are presented. Experimental data are also presented validating the dose calculations. The design of small, lower cost ion accelerators, as embodied in `nested`-tandem and radio frequency quadrupole accelerators is examined, as is the potential use of high-output {sup 3}He and deuterium ion sources. Finally, potential clinical applications are discussed in terms of the advantages and disadvantages of this technique with respect to current radiotherapy methods and equipment.

  10. Tungsten fragmentation in nuclear reactions induced by high-energy cosmic-ray protons

    SciTech Connect

    Chechenin, N. G. Chuvilskaya, T. V.; Shirokova, A. A.; Kadmenskii, A. G.

    2015-01-15

    Tungsten fragmentation arising in nuclear reactions induced by cosmic-ray protons in space-vehicle electronics is considered. In modern technologies of integrated circuits featuring a three-dimensional layered architecture, tungsten is frequently used as a material for interlayer conducting connections. Within the preequilibrium model, tungsten-fragmentation features, including the cross sections for the elastic and inelastic scattering of protons of energy between 30 and 240 MeV; the yields of isotopes and isobars; their energy, charge, and mass distributions; and recoil energy spectra, are calculated on the basis of the TALYS and EMPIRE-II-19 codes. It is shown that tungsten fragmentation affects substantially forecasts of failures of space-vehicle electronics.

  11. Role of Electronic Structure In Ion Band State Theory of Low Energy Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Chubb, Scott

    2004-03-01

    The Nuts and Bolts of our Ion Band State (IBS) theory of low energy nuclear reactions (LENR's) in palladium-deuteride (PdD) and palladium-hydride (PdH) are the electrons that hold together or tear apart the bonds (or lack of bonds) between deuterons (d's) or protons (p's) and the host material. In PdDx and PdH_x, this bonding is strongly correlated with loading: in ambient loading conditions (x< 0. 6), the bonding in hibits IBS occupation. As x arrow 1, slight increases and decreases in loading can lead to vibrations (which have conventionally been thought to occur from phonons) that can induce potential losses or increases of p/d. Naive assumptions about phonons fail to include these losses and increases. These effects can occur because neither H or D has core electrons and because in either PdD or PdH, the electrons near the Fermi Energy have negligible overlap with the nucleus of either D or H. I use these ideas to develop a formal justification, based on a generalization of conventional band theory (Scott Chubb, "Semi-Classical Conduction of Charged and Neutral Particles in Finite Lattices," 2004 March Meeting."), for the idea that occupation of IBS's can occur and that this can lead to nuclear reactions.

  12. From low- to high-energy nuclear data evaluations. Issues and perspectives on nuclear reaction models and covariances

    NASA Astrophysics Data System (ADS)

    Tamagno, P.; De Saint Jean, C.; Bouland, O.; Noguère, G.; Archier, P.; Privas, E.; Serot, O.

    2015-12-01

    Evaluation of neutron cross sections between 0eV and 20MeV is based on several aspects of nuclear physics such as nuclear reaction and structure models and microscopic and integral measurements. Most of the time, the evaluation process is separately done in the resolved resonance range and the continuum. It may give rise to non-physical mismatches of cross sections and large uncertainties at boundaries. It also leads to an absence of cross correlations between high-energy domain and resonance range. In addition, integral experiments are sometimes only used to check central values (evaluation is "working fine" on a dedicated set of benchmarks). Eventual reduction of uncertainties on cross sections is not straightforward: "working fine" could be mathematically turned into reduced uncertainties. This paper will present several ideas that could be used to avoid such effects. They are based on basic physical principles, recent advances in terms of covariance evaluation methodologies, intensive use of Monte Carlo methods and High Performance Computing (HPC) and on some newly introduced models. A clear connection is made between resonance and continuum energy ranges.

  13. Low-Energy Nuclear Reactions Resulting as Picometer Interactions with Similarity to K-Shell Electron Capture

    NASA Astrophysics Data System (ADS)

    Hora, H.; Miley, G. H.; Li, X. Z.; Kelly, J. C.; Osman, F.

    2006-02-01

    Since the appeal by Brian Josephson at the meeting of the Nobel Laureates July 2004, it seems to be indicated to summarize the following serious, reproducible and confirmed observations on reactions of protons or deuterons incorporated in host metals such as palladium. Some reflections to Rutherford's discovery of nuclear physics, the Cockroft-Oliphant discovery of anomalous low-energy fusion reactions and the chemist Hahn's discovery of fission had to be included. Using gaseous atmosphere or discharges between palladium targets, rather significant results were seen e.g. from the "life after death" heat production of such high values per host atom that only nuclear reactions can be involved. This supports the earlier evaluation of neutron generation in fully reversible experiments with gas discharges hinting that a reasonable screening effect - preferably in the swimming electron layer - may lead to reactions at nuclear distances d of picometers with reaction probability times U of about megaseconds similar to the K-shell capture radioactivity. Further electrolytic experiments led to low-energy nuclear reactions (LENR) where the involvement of pollution could be excluded from the appearance of very seldom rare earth elements. A basically new theory for DD cross-sections is used to confirm the picometer-megasecond reactions of cold fusion. Other theoretical aspects are given from measured heavy element distributions similar to the standard abundance distribution, SAD, in the Universe with consequences on endothermic heavy nuclei generation, magic numbers and to quark-gluon plasmas.

  14. Tracking of Ions Produced at Near Barrier Energies in Nuclear Reactions

    SciTech Connect

    Shapira, Dan

    2010-01-01

    Examples of detectors, presently in use, for tracking products from nuclear reactions induced by radioactive ion beams are described. A new tracking detector is being designed to study the binary products from reactions induced by heavy neutron-rich radioactive ion beams on heavy neutron-rich target nuclei. The motivation for such studies and the features designed to accomplish this goal will be presented.

  15. Nuclear reactions from lattice QCD

    DOE PAGES

    Briceño, Raúl A.; Davoudi, Zohreh; Luu, Thomas C.

    2015-01-13

    In this study, one of the overarching goals of nuclear physics is to rigorously compute properties of hadronic systems directly from the fundamental theory of strong interactions, Quantum Chromodynamics (QCD). In particular, the hope is to perform reliable calculations of nuclear reactions which will impact our understanding of environments that occur during big bang nucleosynthesis, the evolution of stars and supernovae, and within nuclear reactors and high energy/density facilities. Such calculations, being truly ab initio, would include all two-nucleon and three- nucleon (and higher) interactions in a consistent manner. Currently, lattice QCD provides the only reliable option for performing calculationsmore » of some of the low-energy hadronic observables. With the aim of bridging the gap between lattice QCD and nuclear many-body physics, the Institute for Nuclear Theory held a workshop on Nuclear Reactions from Lattice QCD on March 2013. In this review article, we report on the topics discussed in this workshop and the path planned to move forward in the upcoming years.« less

  16. Nuclear reactions from lattice QCD

    SciTech Connect

    Briceño, Raúl A.; Davoudi, Zohreh; Luu, Thomas C.

    2015-01-13

    In this study, one of the overarching goals of nuclear physics is to rigorously compute properties of hadronic systems directly from the fundamental theory of strong interactions, Quantum Chromodynamics (QCD). In particular, the hope is to perform reliable calculations of nuclear reactions which will impact our understanding of environments that occur during big bang nucleosynthesis, the evolution of stars and supernovae, and within nuclear reactors and high energy/density facilities. Such calculations, being truly ab initio, would include all two-nucleon and three- nucleon (and higher) interactions in a consistent manner. Currently, lattice QCD provides the only reliable option for performing calculations of some of the low-energy hadronic observables. With the aim of bridging the gap between lattice QCD and nuclear many-body physics, the Institute for Nuclear Theory held a workshop on Nuclear Reactions from Lattice QCD on March 2013. In this review article, we report on the topics discussed in this workshop and the path planned to move forward in the upcoming years.

  17. New supersonic gas jet target for low energy nuclear reaction studies

    NASA Astrophysics Data System (ADS)

    Favela, F.; Acosta, L.; Andrade, E.; Araujo, V.; Huerta, A.; de Lucio, O. G.; Murillo, G.; Ortiz, M. E.; Policroniades, R.; Santa Rita, P.; Varela, A.; Chávez, E.

    2015-12-01

    A windowless supersonic gas jet target (SUGAR) has been put in operation recently in Mexico. It is the first target of its kind in the country and the region. New research opportunities become available with this facility through the study of the direct beam-gas interaction: nuclear physics and astrophysics, atomic physics, interaction of radiation with matter and other interdisciplinary applications. A general description of the apparatus and its commissioning is given here. Air, nitrogen and argon jets were produced. Proton and deuteron beams were used to measure key parameters of the system to compare with theoretical estimates. In addition, as a first study case, we present data from the 14N (d ,α )12C reaction, at center of mass energies between 1.9 and 3.0 MeV with an E-Δ E telescope detector at 35°. Excitation functions for several excited states were constructed and an 16O resonance at 22.72 MeV was confirmed.

  18. Alternative Interpretation of Low-Energy Nuclear Reaction Processes with Deuterated Metals Based on the Bose-Einstein Condensation Mechanism

    NASA Astrophysics Data System (ADS)

    Kim, Yeong E.; Passell, Thomas O.

    2006-02-01

    Recently, a generalization of the Bose-Einstein condensation (BEC) mechanism has been made to a ground-state mixture of two different species of positively charged bosons in harmonic traps. The theory has been used to describe (D + Li) reactions in the low energy nuclear reaction (LENR) processes in condensed matter and predicts that the (D + Li) reaction rates can be larger than (D + D) reaction rates by as much as a factor of ~50, implying that (D + Li) reactions may be occuring in addition to the (D + D) reactions. A survey of the existing data from LENR experiments is carried out to check the validity of the theoretical prediction. We conclude that there is compelling experimental evidence which support the theoretical prediction. New experimental tests of the theoretical prediction are suggested.

  19. New Cooperative Mechanisms of Low-Energy Nuclear Reactions Using Super Low-Energy External Field

    NASA Astrophysics Data System (ADS)

    Gareev, F. A.; Zhidkova, I. E.

    We propose a new mechanism of LENR: cooperative processes in the whole system, nuclei + atoms + condensed matter, can occur at a smaller threshold energies than the corresponding ones on free constituents. The cooperative processes can be induced and enhanced by low-energy external fields. The excess heat is the emission of internal energy and transmutations at LENR are the result of redistribution of inner energy of the whole system.

  20. Computer experiments concerning palladium-deuterium and titanium-deuterium lattices - implications to phenomenon of low-energy nuclear reaction

    SciTech Connect

    Rao, K.R.; Chaplot, S.L.

    1996-12-01

    Short-lived large energy fluctuations (SLEFs) in solids, proposed by Khait, are known to be responsible for several anomalous properties in a variety of materials. The study of SLEFs in palladium-deuterium and titanium-deuterium lattices via computer experiments is reported. The relevance of these large energy fluctuations in penetrating coulombic barriers in these systems is discussed. Such dynamical effects arising from the phonon bath in solids may enhance nuclear reaction probabilities leading to cold fusion. Expected cold fusion reaction rates are reported taking into account the effective charges of the deuterium atoms in the solid and SLEF frequencies. 25 refs., 7 figs., 1 tab.

  1. Micro-radiosurgery: a new concept for radiotherapy based upon low energy, ion-induced nuclear reactions

    NASA Astrophysics Data System (ADS)

    Horn, K. M.; Doyle, B. L.

    1993-06-01

    Traditionally, proton radiotherapy has required the use of high energy proton beams (50-200 MeV) which can penetrate into a patient's body to the site of a tumor that is to be destroyed through irradiation. However, substantial damage is still done to healthy tissue along the path of the incident proton beam, as much as 30% of that done at the tumor site. We propose a new concept for the production and delivery of energetic protons for use in medical radiotherapy, based upon the fact that low energy, ion-induced nuclear reactions can produce radiation products suitable for use in radiotherapy applications. By employing specially fabricated "conduit needles" to deliver beams of energetic ions to selected target materials plugging the end of the needle, ion beam-induced nuclear reactions can be generated at the needle tip, emitting reaction-specific radiation products directly at the tumor site. In this paper, we show that the 13.6 MeV protons produced by the d( 3He, p) 4He nuclear reaction can deliver a lethal dose (7 krad) of radiation to a 4.4 mm diameter sphere of tissue in only 30 s using a 1 μA, 800 keV 3He ion beam. If also proven clinically feasible, the use of low energy, ion-induced nuclear reactions would allow the utilization of relatively inexpensive, compact, low energy ion accelerators for proton radiotherapy and minimize unintended radiation damage to healthy tissue by providing much greater precision in controlling the irradiated volume.

  2. Low-Energy Nuclear Reactions In Low-Temperature Dense Plasmas

    SciTech Connect

    Kasagi, J.; Toriyabe, Y.; Yoshida, E.; Fang, K. H.; Yonemura, H.

    2010-06-01

    We report the Li+d reaction with liquid Li target and the D+D reaction in liquid Li with ultrasonic cavitation. The screening potential of the Li+d reaction has been deduce from the thick target yields of alpha particles emitted in the {sup 6}Li(d,alpha){sup 4} He reaction in the solid and liquid phase. The deduced screening potential for the liquid Li is about 180 eV larger than for the solid. This difference is considered to attributed to the effect of liquefied Li{sup +} ions. It is found out that the D+D reaction in liquid Li with ultrasonic cavitation is enhanced very much; the enhancement corresponds to effective energy increase of about 2000 eV.

  3. Laser induced nuclear reactions

    SciTech Connect

    Ledingham, Ken; McCanny, Tom; Graham, Paul; Fang Xiao; Singhal, Ravi; Magill, Joe; Creswell, Alan; Sanderson, David; Allott, Ric; Neely, David; Norreys, Peter; Santala, Marko; Zepf, Matthew; Watts, Ian; Clark, Eugene; Krushelnick, Karl; Tatarakis, Michael; Dangor, Bucker; Machecek, Antonin; Wark, Justin

    1998-12-16

    Dramatic improvements in laser technology since 1984 have revolutionised high power laser technology. Application of chirped-pulse amplification techniques has resulted in laser intensities in excess of 10{sup 19} W/cm{sup 2}. In the mid to late eighties, C. K. Rhodes and K. Boyer discussed the possibility of shining laser light of this intensity onto solid surfaces and to cause nuclear transitions. In particular, irradiation of a uranium target could induce electro- and photofission in the focal region of the laser. In this paper it is shown that {mu}Ci of {sup 62}Cu can be generated via the ({gamma},n) reaction by a laser with an intensity of about 10{sup 19} Wcm{sup -2}.

  4. Reaction models in nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Descouvemont, Pierre

    2016-05-01

    We present different reaction models commonly used in nuclear astrophysics, in particular for the nucleosynthesis of light elements. Pioneering works were performed within the potential model, where the internal structure of the colliding nuclei is completely ignored. Significant advances in microscopic cluster models provided the first microscopic description of the 3He(α,&gamma)7 Be reaction more than thirty years ago. In this approach, the calculations are based on an effective nucleon-nucleon interaction, but the cluster approximation should be made to simplify the calculations. Nowadays, modern microscopic calculations are able to go beyond the cluster approximation, and aim at finding exact solutions of the Schrödinger equation with realistic nucleon-nucleon interactions. We discuss recent examples on the d+d reactions at low energies.

  5. COMMENTS ON "A NEW LOOK AT LOW-ENERGY NUCLEAR REACTION RESEARCH"

    SciTech Connect

    Shanahan, K.

    2009-12-30

    Cold fusion researchers have accumulated a large body of anomalous results over the last 20 years that they claim proves a new, mysterious nuclear reaction is active in systems they study. Krivit and Marwan give a brief and wholly positive view of this body of research. Unfortunately, cold fusion researchers routinely ignore conventional explanations of their observations, and claim much greater than real accuracy and precision for their techniques. This paper attempts to equally briefly address those aspects of the field with the intent of providing a balanced view of the field, and to establish some criteria for subsequent publications in this arena.

  6. Transfer reactions in nuclear astrophysics

    NASA Astrophysics Data System (ADS)

    Bardayan, D. W.

    2016-08-01

    To a high degree many aspects of the large-scale behavior of objects in the Universe are governed by the underlying nuclear physics. In fact the shell structure of nuclear physics is directly imprinted into the chemical abundances of the elements. The tranquility of the night sky is a direct result of the relatively slow rate of nuclear reactions that control and determines a star’s fate. Understanding the nuclear structure and reaction rates between nuclei is vital to understanding our Universe. Nuclear-transfer reactions make accessible a wealth of knowledge from which we can extract much of the required nuclear physics information. A review of transfer reactions for nuclear astrophysics is presented with an emphasis on the experimental challenges and opportunities for future development.

  7. Method and apparatus for generating high-energy nuclear reactions by low-energy ion bombardment of solids

    SciTech Connect

    Grabowski, K.; Eridon, J.; Chambers, G.; Hubler, G.

    1992-01-01

    A method and apparatus for producing an exoergic nuclear reaction. A target made of solid material is positioned in a vacuum chamber containing deuterium gas and having an operating pressure below atmospheric pressure. The target is ion bombarded with a deuterium ion beam produced by an electron cyclotron resonance microwave plasma source.

  8. Neutron Energy Spectra and Yields from the 7Li(p,n) Reaction for Nuclear Astrophysics

    NASA Astrophysics Data System (ADS)

    Tessler, M.; Friedman, M.; Schmidt, S.; Shor, A.; Berkovits, D.; Cohen, D.; Feinberg, G.; Fiebiger, S.; Krása, A.; Paul, M.; Plag, R.; Plompen, A.; Reifarth, R.

    2016-01-01

    Neutrons produced by the 7Li(p, n)7Be reaction close to threshold are widely used to measure the cross section of s-process nucleosynthesis reactions. While experiments have been performed so far with Van de Graaff accelerators, the use of RF accelerators with higher intensities is planned to enable investigations on radioactive isotopes. In parallel, high-power Li targets for the production of high-intensity neutrons at stellar energies are developed at Goethe University (Frankfurt, Germany) and SARAF (Soreq NRC, Israel). However, such setups pose severe challenges for the measurement of the proton beam intensity or the neutron fluence. In order to develop appropriate methods, we studied in detail the neutron energy distribution and intensity produced by the thick-target 7Li(p,n)7Be reaction and compared them to state-of- the-art simulation codes. Measurements were performed with the bunched and chopped proton beam at the Van de Graaff facility of the Institute for Reference Materials and Measurements (IRMM) using the time-of-flight (TOF) technique with thin (1/8") and thick (1") detectors. The importance of detailed simulations of the detector structure and geometry for the conversion of TOF to a neutron energy is stressed. The measured neutron spectra are consistent with those previously reported and agree well with Monte Carlo simulations that include experimentally determined 7Li(p,n) cross sections, two-body kinematics and proton energy loss in the Li-target.

  9. Exploring the Symmetry Energy of Asymmetric Nuclear Matter with Heavy Ion Reactions

    NASA Astrophysics Data System (ADS)

    Tsang, M. B.

    2008-04-01

    The nuclear symmetry energy governs many properties of neutron-rich nuclei and of neutron stars. Neutron star radii, moments of inertia, phase transitions in the stellar interior and the cooling of proto-neutron stars are among the stellar properties that are most strongly affected. A number of interesting experimental observables have been identified that provide opportunities to probe the density dependence of the symmetry energy via nucleus-nucleus collisions. In this talk, we discuss measurements and simulations of the isospin diffusion and neutron to proton emission observable over a wide incident energy range. This work is supported by the National Science Foundation under Grant Nos. PHY-01-10253, PHY-0606007.

  10. Nuclear energy.

    PubMed

    Grandin, Karl; Jagers, Peter; Kullander, Sven

    2010-01-01

    Nuclear energy can play a role in carbon free production of electrical energy, thus making it interesting for tomorrow's energy mix. However, several issues have to be addressed. In fission technology, the design of so-called fourth generation reactors show great promise, in particular in addressing materials efficiency and safety issues. If successfully developed, such reactors may have an important and sustainable part in future energy production. Working fusion reactors may be even more materials efficient and environmental friendly, but also need more development and research. The roadmap for development of fourth generation fission and fusion reactors, therefore, asks for attention and research in these fields must be strengthened.

  11. Nuclear energy.

    PubMed

    Grandin, Karl; Jagers, Peter; Kullander, Sven

    2010-01-01

    Nuclear energy can play a role in carbon free production of electrical energy, thus making it interesting for tomorrow's energy mix. However, several issues have to be addressed. In fission technology, the design of so-called fourth generation reactors show great promise, in particular in addressing materials efficiency and safety issues. If successfully developed, such reactors may have an important and sustainable part in future energy production. Working fusion reactors may be even more materials efficient and environmental friendly, but also need more development and research. The roadmap for development of fourth generation fission and fusion reactors, therefore, asks for attention and research in these fields must be strengthened. PMID:20873683

  12. On the idea of low-energy nuclear reactions in metallic lattices by producing neutrons from protons capturing "heavy" electrons

    NASA Astrophysics Data System (ADS)

    Tennfors, Einar

    2013-02-01

    The present article is a critical comment on Widom and Larsens speculations concerning low-energy nuclear reactions (LENR) based on spontaneous collective motion of protons in a room temperature metallic hydride lattice producing oscillating electric fields that renormalize the electron self-energy, adding significantly to the effective electron mass and enabling production of low-energy neutrons. The frequency and mean proton displacement estimated on the basis of neutron scattering from protons in palladium and applied to the Widom and Larsens model of the proton oscillations yield an electron mass enhancement less than one percent, far below the threshold for the proposed neutron production and even farther below the mass enhancement obtained by Widom and Larsen assuming a high charge density. Neutrons are not stopped by the Coulomb barrier, but the energy required for the neutron production is not low.

  13. Nuclear excitation and precompound nuclear reactions

    SciTech Connect

    De, A.; Ray, S.; Ghosh, S.K.

    1988-06-01

    The angular distribution of nucleons emitted in nucleon-induced precompound nuclear reactions are calculated taking into account the effect of excitation on the kinematics of nucleon-nucleon scattering inside the target-plus-projectile system. The results are compared with quantum mechanical calculations and those of reaction models based on a pure nucleon-nucleon collision picture.

  14. Nuclear reaction studies

    SciTech Connect

    Alexander, J.M.; Lacey, R.A.

    1994-11-01

    Research focused on the statistical and dynamical properties of ``hot`` nuclei formed in symmetric heavy-ion reactions. Theses included ``flow`` measurements and the mechanism for multifragment disassembly. Model calculations are being performed for the reactions C+C, Ne+Al, Ar+Sc, Kr+Nb, and Xe+La. It is planned to study {sup 40}Ar reactions from 27 to 115 MeV/nucleon. 2 figs., 41 refs.

  15. Disassembly of hot nuclear matter formed in Au-induced reactions near the Fermi energy

    SciTech Connect

    Delis, D.N.

    1993-09-01

    Complex fragment emission has been studied in the 60 MeV/A {sup 197}Au + {sup 12}C, {sup 27}Al, {sup 51}V, {sup nat}Cu, and {sup 197}Au reactions. Velocity spectra, angular distributions and cross sections have been constructed for each target from the inclusive data. Coincidence data including 2-, 3-, 4-, and 5-fold events have also been examined. Furthermore neutron multiplicity distributions have been obtained for the above reactions by utilizing a novel neutron calorimetric approach.

  16. Heavy flavours production in quark-gluon plasma formed in high energy nuclear reactions

    NASA Technical Reports Server (NTRS)

    Kloskinski, J.

    1985-01-01

    Results on compression and temperatures of nuclear fireballs and on relative yield of strange and charmed hadrons are given . The results show that temperatures above 300 MeV and large compressions are unlikely achieved in average heavy ion collision. In consequence, thermal production of charm is low. Strange particle production is, however, substantial and indicates clear temperature - threshold behavior.

  17. The nuclear reaction code McGNASH.

    SciTech Connect

    Talou, P.; Chadwick, M. B.; Chadwick, M B; Young, P. G. ,; Kawano, T.

    2004-01-01

    McGNASH is a modern statitistical/preequilibrium nuclear reaction code, being developed at Los Alamos, which can simulate neutron-, proton- and photon-induced reactions in the energy range from a few-keV to about 150 MeV. It is written in modern Fortran 95 scientific language, offering new capabilities both for the developer and the user. McGNASH is still in a development stage, and a first public release is planned for later in 2005. The statisticaUpre-equilibrium nuclear reaction code GNASH has been used successfully over the years to compute neutron-, proton- and photon-induced reactions cross sections on a variety of nuclei targets, and for incident particle energies from tens of keV up to 150-200 MeV. This code has been instrumental in producing numerous nuclear data evaluation files for various ENDF libraries around the World, and in particular the ENDFB-VI and pre-ENDFB-VII libraries in the US. More recently, GNASH was used extensively for the creation of the LA1501ibrary, including data on neutron- and proton-induced reactions up to 150 MeV incident energy. We are now developing a modern version of the code, called McGNASH.

  18. Nuclear Reactions for Astrophysics and Other Applications

    SciTech Connect

    Escher, J E; Burke, J T; Dietrich, F S; Scielzo, N D; Ressler, J J

    2011-03-01

    Cross sections for compound-nuclear reactions are required for many applications. The surrogate nuclear reactions method provides an indirect approach for determining cross sections for reactions on unstable isotopes, which are difficult or impossible to measure otherwise. Current implementations of the method provide useful cross sections for (n,f) reactions, but need to be improved upon for applications to capture reactions.

  19. Unifying Theory of Low-Energy Nuclear Reaction and Transmutation Processes in Deuterated/hydrogenated Metals, Acoustic Cavitation, Glow Discharge, and Deuteron Beam Experiments

    NASA Astrophysics Data System (ADS)

    Kim, Yeong E.; Zubarev, Alexander L.

    The most basic theoretical challenge for understanding low-energy nuclear reaction (LENR) and transmutation reaction (LETR) in condensed matters is to find mechanisms by which the large Coulomb barrier between fusing nuclei can be overcome. A unifying theory of LENR and LETR has been developed to provide possible mechanisms for the LENR and LETR processes in matters based on high-density nano-scale and micro-scale quantum plasmas. It is shown that recently developed theoretical models based on Bose-Einstein Fusion (BEF) mechanism and Quantum Plasma Nuclear Fusion (QPNF) mechanism are applicable to the results of many different types of LENR and LETR experiments.

  20. Transport-theoretical description of nuclear reactions

    NASA Astrophysics Data System (ADS)

    Buss, O.; Gaitanos, T.; Gallmeister, K.; van Hees, H.; Kaskulov, M.; Lalakulich, O.; Larionov, A. B.; Leitner, T.; Weil, J.; Mosel, U.

    2012-03-01

    In this review we first outline the basics of transport theory and its recent generalization to off-shell transport. We then present in some detail the main ingredients of any transport method using in particular the Giessen Boltzmann-Uehling-Uhlenbeck (GiBUU) implementation of this theory as an example. We discuss the potentials used, the ground state initialization and the collision term, including the in-medium modifications of the latter. The central part of this review covers applications of GiBUU to a wide class of reactions, starting from pion-induced reactions over proton and antiproton reactions on nuclei to heavy-ion collisions (up to about 30 AGeV). A major part concerns also the description of photon-, electron- and neutrino-induced reactions (in the energy range from a few 100 MeV to a few 100 GeV). For this wide class of reactions GiBUU gives an excellent description with the same physics input and the same code being used. We argue that GiBUU is an indispensable tool for any investigation of nuclear reactions in which final-state interactions play a role. Studies of pion-nucleus interactions, nuclear fragmentation, heavy-ion reactions, hypernucleus formation, hadronization, color transparency, electron-nucleus collisions and neutrino-nucleus interactions are all possible applications of GiBUU and are discussed in this article.

  1. Mixtures of Charged Bosons Confined in Harmonic Traps and Bose-Einstein Condensation Mechanism for Low-Energy Nuclear Reactions and Transmutation Processes in Condensed Matters

    NASA Astrophysics Data System (ADS)

    Kim, Yeong E.; Zubarev, Alexander L.

    2006-02-01

    A mixture of two different species of positively charged bosons in harmonic traps is considered in the mean-field approximation. It is shown that depending on the ratio of parameters, the two components may coexist in same regions of space, in spite of the Coulomb repulsion between the two species. Application of this result is discussed for the generalization of the Bose-Einstein condensation mechanism for low-energy nuclear reaction (LENR) and transmutation processes in condensed matters. For the case of deutron-lithium (d + Li) LENR, the result indicates that (d + 6Li) reactions may dominate over (d + d) reactions in LENR experiments.

  2. Nuclear energy.

    PubMed

    Wilson, Peter D

    2010-01-01

    The technical principles and practices of the civil nuclear industry are described with particular reference to fission and its products, natural and artificial radioactivity elements principally concerned and their relationships, main types of reactor, safety issues, the fuel cycle, waste management, issues related to weapon proliferation, environmental considerations and possible future developments.

  3. Coupled-channels density-matrix approach to low-energy nuclear collision dynamics: A technique for quantifying quantum decoherence effects on reaction observables

    SciTech Connect

    Diaz-Torres, Alexis

    2010-11-15

    The coupled-channels density-matrix technique for nuclear reaction dynamics, which is based on the Liouville-von Neumann equation with Lindblad dissipative terms, is developed with the inclusion of full angular momentum couplings. It allows a quantitative study of the role and importance of quantum decoherence in nuclear scattering. Formulas of asymptotic observables that can reveal effects of quantum decoherence are given. A method for extracting energy-resolved scattering information from the time-dependent density matrix is introduced. As an example, model calculations are carried out for the low-energy collision of the {sup 16}O projectile on the {sup 154}Sm target.

  4. Extension of the energy range of experimental activation cross-sections data of deuteron induced nuclear reactions on indium up to 50MeV.

    PubMed

    Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

    2015-11-01

    The energy range of our earlier measured activation cross-sections data of longer-lived products of deuteron induced nuclear reactions on indium were extended from 40MeV up to 50MeV. The traditional stacked foil irradiation technique and non-destructive gamma spectrometry were used. No experimental data were found in literature for this higher energy range. Experimental cross-sections for the formation of the radionuclides (113,110)Sn, (116m,115m,114m,113m,111,110g,109)In and (115)Cd are reported in the 37-50MeV energy range, for production of (110)Sn and (110g,109)In these are the first measurements ever. The experimental data were compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS 1.6 nuclear model code as listed in the on-line library TENDL-2014.

  5. Forging the link between nuclear reactions and nuclear structure

    NASA Astrophysics Data System (ADS)

    Dickhoff, W. H.

    2016-06-01

    A review of the recent applications of the dispersive optical model (DOM) is presented. Emphasis is on the nonlocal implementation of the DOM that is capable of describing ground-state properties accurately when data like the nuclear charge density are available. The present understanding of the role of short- and long-range physics in determining proton properties near the Fermi energy for stable closed-shell nuclei has relied mostly on data from the (e, e' p) reaction. Hadronic tools to extract such spectroscopic information have been hampered by the lack of a consistent reaction description that provides unambiguous and undisputed results. The DOM, conceived by Claude Mahaux, provides a unified description of both elastic nucleon scattering and structure information related to single-particle properties below the Fermi energy. We have recently introduced a nonlocal dispersive optical potential for both the real and imaginary part. Nonlocal absorptive potentials yield equivalent elastic differential cross sections for 40Ca as compared to local ones but change the l-dependent absorption profile suggesting important consequences for the analysis of nuclear reactions. Below the Fermi energy, nonlocality is essential for an accurate representation of particle number and the nuclear charge density. Spectral properties implied by (e, e' p) and (p, 2p) reactions are correctly described, including the energy distribution of about 10% high-momentum protons obtained at Jefferson Lab. The nonlocal DOM allows a complete description of experimental data both above (up to 200 MeV) and below the Fermi energy in 40Ca. It is further demonstrated that elastic nucleon-nucleus scattering data constrain the spectral strength in the continuum of orbits that are nominally bound in the independent-particle model. Extension of this analysis to 48Ca allows a prediction of the neutron skin of this nucleus that is larger than most predictions made so far.

  6. Hadron Cancer Therapy: Role of Nuclear Reactions

    DOE R&D Accomplishments Database

    Chadwick, M. B.

    2000-06-20

    Recently it has become feasible to calculate energy deposition and particle transport in the body by proton and neutron radiotherapy beams, using Monte Carlo transport methods. A number of advances have made this possible, including dramatic increases in computer speeds, a better understanding of the microscopic nuclear reaction cross sections, and the development of methods to model the characteristics of the radiation emerging from the accelerator treatment unit. This paper describes the nuclear reaction mechanisms involved, and how the cross sections have been evaluated from theory and experiment, for use in computer simulations of radiation therapy. The simulations will allow the dose delivered to a tumor to be optimized, whilst minimizing the dos given to nearby organs at risk.

  7. Indirect Methods for Nuclear Reaction Data

    SciTech Connect

    Escher, J E; Dietrich, F S

    2005-11-18

    Several indirect approaches for obtaining reaction cross sections are briefly reviewed. The Surrogate Nuclear Reactions method, which aims at determining cross sections for compound-nuclear reactions, is discussed in some detail. The validity of the Weisskopf-Ewing approximation in the Surrogate approach is studied for the example of neutron-induced fission of an actinide nucleus.

  8. Common sense in nuclear energy

    SciTech Connect

    Hoyle, F.; Hoyle, G.

    1980-01-01

    Public concern about energy resource exhaustion is noted to have developed only after the means (nuclear power) for avoiding this disaster became available and the negative implications of a nuclear society became a focus for anxiety. Ironically, collapse of conventional energy supplies could lead to the nuclear confrontation which anti-nuclear forces claim as the inevitable outcome of nuclear power. A review of the risks, environmental impacts, and political implications of the major energy sources concludes that emotion, not common sense, has made nuclear energy an unpopular option. While the problems of proliferation, radiation protection, waste management, and accident prevention are far from trivial, they will respond to technological improvements and responsible control policies. An historical tradition of fearing new, poorly understood technologies is seen in the reaction to railroads during the early 19th Century. (DCK)

  9. Low-energy fission investigated in reactions of 750 AMeV238U-ions with Pb and Be targets. I. Nuclear charge distributions

    NASA Astrophysics Data System (ADS)

    Armbruster, P.; Bernas, M.; Czajkowski, S.; Geissel, H.; Aumann, T.; Dessagne, Ph.; Donzaud, C.; Hanelt, E.; Heinz, A.; Hesse, M.; Kozhuharov, C.; Miehe, Ch.; Münzenberg, G.; Pfützner, M.; Schmidt, K.-H.; Schwab, W.; Stéphan, C.; Sümmerer, K.; Tassan-Got, L.; Voss, B.

    1996-12-01

    Charge distributions of fragments from low energy nuclear fission are investigated in reactions of highly fissile238U projectiles at relativistic energies (750 A·MeV) with a heavy (Pb) and a light (Be) target. The fully stripped fission fragments are separated by the Fragment Separator (FRS). Their high kinetic energies in the laboratory system allow the identification of all atomic numbers by using Multiple-Sampling Ionization Chambers (MUSIC). The elemental distributions of fragments observed at larger magnetic rigidities than the238U projectiles show asymmetric break-up and odd-even effects. They indicate a low energy fission process, induced mainly by dissociation in the electro-magnetic field for the U/Pb-system, or by peripheral nuclear interactions for the U/Be-system.

  10. High energy halogen atom reactions activated by nuclear transformations. Progress report, February 15, 1980-February 14, 1981

    SciTech Connect

    Not Available

    1981-02-01

    The stereochemistry of high energy /sup 18/F, /sup 34m/Cl, and /sup 76/Br substitution reactions involving enantiomeric molecules in the gas and condensed phase is studied. The gas to condensed state transition in halogen high energy chemistry, involving chlorine, bromine, and iodine activated by the (n,..gamma..) and (I.T.) processes in halomethanes, saturated and unsaturated hydrocarbons is being investigated in more detail. Special attention is given to defining the nature of the enhancement yields in the condensed phase. High energy halogen reactions in liquid and frozen aqueous solutions of organic and biomolecular solutes are studied in an attempt to learn more about these reactions. The applications of high energy chemistry techniques and theory to neutron activation analysis of biological systems are being continued. Special attention is given to developing procedures for trace molecular determinations in biological systems. The applications of hot halogen atoms as indicators of solute-solute interactions in liquid and frozen aqueous solutions of halogenated bases and nucleosides are being developed. Experiments are designed to explain the mechanisms of the radioprotection offered biomolecular solutes trapped within the frozen ice lattice. Reactions of bromine and iodine activated by isomeric transition with halogenated biomolecular solutes in liquid and frozen aqueous solutions are studied. The high energy reactions of iodine with the isomers of pentene have been studied in low pressure gaseous systems employing additives and rare gas moderators and liquid systems. Reactivity of excited complex formation and structural effects of electrophilic iodine attack on the pi-bond systems are studied.

  11. High energy halogen atom reactions activated by nuclear transformations. Progress report, February 15, 1979-February 14, 1980

    SciTech Connect

    Rack, E.P.

    1980-02-01

    The program consists of six interrelated areas: (1) Reactions of iodine with alkenes and alkynes activated by radiative neutron capture and isomeric transition in low pressure gaseous systems employing additives and rare gas moderators, high pressure, and liquid systems. Special attention was given to the reactivity of excited complex formation and structural effects of electrophilic iodine attack on various pi-bond systems. (2) The gas-to-condensed phase transition in halogen high energy chemistry. Current interest involves the study of caging effects of an ice lattice on recombination reactions involving neutron-irradiated frozen aqueous solutions of halogenated organic and biochemical solutes in order to learn more about kinetic energy effects, halogen size, solute molecule size, steric effects and hydrogen bonding within an ice lattice cage. (3) Systematics of halogen hot atom reactions. The reactions of /sup 80m/Br, /sup 80/Br, /sup 82m/Br + /sup 82/Br, /sup 82/Br, /sup 82/Br, /sup 128/I, /sup 130/I, and /sup 130m/I + /sup 130/I activated by radiative neutron capture or isomeric transition in hydrocarbons and halo-substituted alkanes in low pressure and high pressure gaseous systems employing additives and rare gas moderators are currently being studied. (4) Mathematical and computer simulation studies of caging events within an ice lattice are being investigated. (5) At Brookhaven National Laboratory, cyclotron-produced chlorine and fluorine hot atoms substitution reactions with molecules possessing a single chiral center are under investigation to determine the role of hot atom kinetic energy, halogen atom, enantioner structure, steric effects and phase on the extent of substitution by retention of configuration or by Walden inversion. (6) The applications of high energy techniques and concepts to neutron activation analysis for trace element determinations in biological systems was continued.

  12. Forging the link between nuclear reactions and nuclear structure.

    PubMed

    Mahzoon, M H; Charity, R J; Dickhoff, W H; Dussan, H; Waldecker, S J

    2014-04-25

    A comprehensive description of all single-particle properties associated with the nucleus Ca40 is generated by employing a nonlocal dispersive optical potential capable of simultaneously reproducing all relevant data above and below the Fermi energy. The introduction of nonlocality in the absorptive potentials yields equivalent elastic differential cross sections as compared to local versions but changes the absorption profile as a function of angular momentum suggesting important consequences for the analysis of nuclear reactions. Below the Fermi energy, nonlocality is essential to allow for an accurate representation of particle number and the nuclear charge density. Spectral properties implied by (e, e'p) and (p, 2p) reactions are correctly incorporated, including the energy distribution of about 10% high-momentum nucleons, as experimentally determined by data from Jefferson Lab. These high-momentum nucleons provide a substantial contribution to the energy of the ground state, indicating a residual attractive contribution from higher-body interactions for Ca40 of about 0.64  MeV/A.

  13. Random-matrix approach to the statistical compound nuclear reaction at low energies using the Monte-Carlo technique

    SciTech Connect

    Kawano, Toshihiko

    2015-11-10

    This theoretical treatment of low-energy compound nucleus reactions begins with the Bohr hypothesis, with corrections, and various statistical theories. The author investigates the statistical properties of the scattering matrix containing a Gaussian Orthogonal Ensemble (GOE) Hamiltonian in the propagator. The following conclusions are reached: For all parameter values studied, the numerical average of MC-generated cross sections coincides with the result of the Verbaarschot, Weidenmueller, Zirnbauer triple-integral formula. Energy average and ensemble average agree reasonably well when the width I is one or two orders of magnitude larger than the average resonance spacing d. In the strong-absorption limit, the channel degree-of-freedom ν a is 2. The direct reaction increases the inelastic cross sections while the elastic cross section is reduced.

  14. Nuclear reactions in Monte Carlo codes.

    PubMed

    Ferrari, A; Sala, P R

    2002-01-01

    The physics foundations of hadronic interactions as implemented in most Monte Carlo codes are presented together with a few practical examples. The description of the relevant physics is presented schematically split into the major steps in order to stress the different approaches required for the full understanding of nuclear reactions at intermediate and high energies. Due to the complexity of the problem, only a few semi-qualitative arguments are developed in this paper. The description will be necessarily schematic and somewhat incomplete, but hopefully it will be useful for a first introduction into this topic. Examples are shown mostly for the high energy regime, where all mechanisms mentioned in the paper are at work and to which perhaps most of the readers are less accustomed. Examples for lower energies can be found in the references.

  15. Quantitative Analysis of Plutonium Content in Particles Collected from a Certified Reference Material by Total Nuclear Reaction Energy (Q Value) Spectroscopy

    NASA Astrophysics Data System (ADS)

    Croce, M. P.; Hoover, A. S.; Rabin, M. W.; Bond, E. M.; Wolfsberg, L. E.; Schmidt, D. R.; Ullom, J. N.

    2016-08-01

    Microcalorimeters with embedded radioisotopes are an emerging category of sensor with advantages over existing methods for isotopic analysis of trace-level nuclear materials. For each nuclear decay, the energy of all decay products captured by the absorber (alpha particles, gamma rays, X-rays, electrons, daughter nuclei, etc.) is measured in one pulse. For alpha-decaying isotopes, this gives a measurement of the total nuclear reaction energy (Q value) and the spectra consist of well-separated, narrow peaks. We have demonstrated a simple mechanical alloying process to create an absorber structure consisting of a gold matrix with small inclusions of a radioactive sample. This absorber structure provides an optimized energy thermalization environment, resulting in high-resolution spectra with minimal tailing. We have applied this process to the analysis of particles collected from the surface of a plutonium metal certified reference material (CRM-126A from New Brunswick Laboratory) and demonstrated isotopic analysis by microcalorimeter Q value spectroscopy. Energy resolution from the Gaussian component of a Bortels function fit was 1.3 keV FWHM at 5244 keV. The collected particles were integrated directly into the detector absorber without any chemical processing. The ^{238}Pu/^{239}Pu and ^{240}Pu/^{239}Pu mass ratios were measured and the results confirmed against the certificate of analysis for the reference material. We also demonstrated inter-element analysis capability by measuring the ^{241}Am/^{239}Pu mass ratio.

  16. Model for particle production in nuclear reactions at intermediate energies: Application to C-C collisions at 95 MeV/nucleon

    NASA Astrophysics Data System (ADS)

    Dudouet, J.; Durand, D.

    2016-07-01

    A model describing nuclear collisions at intermediate energies is presented and the results are compared with recently measured double differential cross sections in C-C reactions at 95 MeV/nucleon. Results show the key role played by geometrical effects and the memory of the entrance channel, in particular the momentum distributions of the two incoming nuclei. Special attention is paid to the description of processes occurring at midrapidity. To this end, a random particle production mechanism by means of a coalescence process in velocity space is considered in the overlap region of the two interacting nuclei.

  17. EXFOR Library of Experimental Nuclear Reaction Data

    DOE Data Explorer

    The EXFOR library contains an extensive compilation of experimental nuclear reaction data up to 1 GeV. Neutron reactions have been compiled systematically since the discovery of the neutron, while charged particle(up to carbon) and photon reactions have been covered less extensively. Files contain nuclear reaction data such as cross sections, spectra, angular distributions, polarizations, etc, along with information on experimental technique, error analysis, and applied standards. Numerous search parameters include: target, beam, product, experimental method, and even author and publication names. The library contains data from more than 20,000 experiments. (Specialized Interface)

  18. Decoherence in nuclear collisions: Towards a new understanding of near Coulomb barrier nuclear reactions

    SciTech Connect

    Evers, M.; Dasgupta, M.; Hinde, D. J.

    2010-04-26

    To understand the underlying physical processes that might lead to loss of quantum coherence, high precision quasi-elastic excitation functions at sub-barrier energies were measured. Results show transfer events to high excitation energies, which may be impossible to model in a coherent picture. This points to the need to explicitly include quantum decoherence in nuclear reaction models and ultimately to a new understanding of near Coulomb barrier nuclear reactions.

  19. Nuclear energy technology

    NASA Technical Reports Server (NTRS)

    Buden, David

    1992-01-01

    An overview of space nuclear energy technologies is presented. The development and characteristics of radioisotope thermoelectric generators (RTG's) and space nuclear power reactors are discussed. In addition, the policy and issues related to public safety and the use of nuclear power sources in space are addressed.

  20. Compilation of Nuclear Reaction Data from RIBF

    NASA Astrophysics Data System (ADS)

    Makinaga, Ayano; Ebata, Shuichiro; Aikawa, Masayuki; Furutachi, Naoya; Ichinkhorloo, Dagvadorj; Katō, Kiyoshi; Odsuren, Myagmarjav; Devi, Vidya; Otuka, Naohiko; Kohama, Akihisa; Otsu, Hideaki; Sakurai, Hiroyoshi

    Nuclear reaction data are useful in many fields, e.g., nuclear physics, astrophysics, nuclear engineering, and radiation therapy. It is therefore desirable to make such data freely available through a database. One such database is the EXFOR library, which is maintained under international cooperation. For the benefit of nuclear data users worldwide, the experimental nuclear data obtained at the RIKEN Radioisotope Beam Factory (RIBF) are continuously transmitted into the EXFOR library. We are effectively improving the completeness and usability of the data produced at the RIBF. In addition, a new format is being discussed to create convenient access to the databases for experimentalists and users.

  1. Ion transport of Fr nuclear reaction products

    SciTech Connect

    Behr, J.A.; Cahn, S.B.; Dutta, S.B.

    1993-04-01

    Experiments planned for fundamental studies of radioactive atoms in magneto-optic traps require efficient deceleration and transport of nuclear reaction products to energies and locations where they can be trapped. The authors have built a low-energy ion transport system for Francium and other alkalis. A thick Au target is held on a W rod at 45{degrees} to the accelerator beam direction. The heavy-ion fusion reaction 115 MeV {sup 18}O + {sup 197}Au produces {sup 211,210,209}Fr recoil products which are stopped in the target. The target is heated to close to the melting point of Au to allow the Fr to diffuse to the surface, where it is ionized due to Au`s high work function, and is directly extracted by an electrode at 90{degrees} to the accelerator beam direction. The Fr is transported by electrostatic optics {approximately}1 m to a catcher viewed by an {alpha} detector: {ge}15% of the Fr produced in the target reaches the catcher. 2{times}10{sup 5} Fr/sec have been produced at the catcher, yielding at equilibrium a sample of 3x10{sup 7}Fr nuclei. This scheme physically decouples the target diffusion from the surface neutralization process, which can occur at a lower temperature more compatible with the neutral-atom trap.

  2. Public reactions to nuclear waste

    SciTech Connect

    Dunlap, R.E.; Kraft, M.E.; Rosa, E.A.

    1993-12-31

    For many scientists, engineers, and regulators, the public controversy over siting a repository for high-level nuclear wastes exemplifies the clash between rational scientific judgment and irrational public attitudes. Even many who are more sympathetic to public concerns about risk and management believe the controversy is exacerbated by incompatibilities between good science and public participation in regulatory decision-making. Understanding the incompatibilities, however, is crucial to managing science and technology in a democratic society and provides an important motivation to study the relationship between public opinion and nuclear waste policy. In this book, Dunlap and his colleagues present a solid base of empirical research on the subject, and the strength of the collection is the careful unraveling of social factors and context to explain the overwhelmingly negative public view of nuclear waste and its management.

  3. Nuclear chain reaction: forty years later

    SciTech Connect

    Sachs, R.G.

    1984-01-01

    The proceedings from a 1982 symposium 40 years after the first controlled nuclear chain reaction took place in Chicago covers four sessions and public discussion. The session covered the history of the chain reaction; peaceful uses in technology, medicine, and biological science; peaceful uses in power generation; and nuclear weapons control. Among the speakers were Eugene Wigner, Glenn Seaborg, Alvin Weinberg, and others who participated in the first chain reaction experiments. The proceedings reflect differences of opinion among the scientists as well as the general public. References, slides, and tables used to illustrate the individual talks are included with the papers.

  4. Experimental nuclear reaction data collection EXFOR

    SciTech Connect

    Semkova, V.; Otuka, N.; Simakov, S. P.; Zerkin, V.

    2011-07-01

    The International Network of Nuclear Reaction Data Centres (NRDC) constitutes a worldwide cooperation of 14 nuclear data centres. The main activity of the NRDC Network is collection and compilation of experimental nuclear reaction cross section data and the related bibliographic information in the EXFOR and CINDA databases as well as dissemination of nuclear reaction data and associated documentation to users. The database contains information and numerical data from more than about 19000 experiments consisting of more than 140000 datasets. EXFOR is kept up to date by constantly adding newly published experimental information. Tools developed for data dissemination utilise modern database technologies with fast online capabilities over the Internet. Users are provided with sophisticated search options, a user-friendly retrieval interface for downloading data in different formats, and additional output options such as improved data plotting capabilities. The present status of the EXFOR database will be presented together with the latest development for data access and retrieval. (authors)

  5. Towards gauge-independent treatment of radiative capture in nuclear reactions: Applications to low-energy cluster-cluster collisions

    NASA Astrophysics Data System (ADS)

    Shebeko, A. V.

    2014-04-01

    Our departure point in describing electromagnetic (EM) interactions with nuclei (in general, bound systems of charged particles) is to use the Fock-Weyl criterion and a generalization of the Siegert theorem. It is shown how one can meet the gauge invariance principle (GIP) in all orders in the charge and construct the corresponding EM interaction operators in case of nuclear forces arbitrarily dependent on velocity. Along the guideline we have derived the conserved current density operator for a dicluster system (more precisely, the system of two finite-size clusters with many-body interaction effects included). In the context, we are addressing the current clusterization as a first step when accounting for possible cluster excitations. Being expressed through the electric and magnetic field strengths and matrix elements of the so-called generalized electric and magnetic dipole moments of the system, associated with the conserved current, the single-photon transition amplitude attains a manifestly gauge-independent (GI) form. The latter is essentially simplified at low energies.

  6. Nuclear structure from direct reactions with rare isotopes: observables, methods and highlights

    NASA Astrophysics Data System (ADS)

    Obertelli, Alexandre

    2016-09-01

    An overview of direct reactions employed for nuclear structure studies is presented. The basic and most used analysis methods of elastic and inelastic scattering, transfer reactions and intermediate-energy removal reactions are reviewed. The most relevant observables from direct reactions regarding the nuclear many-body problem, as well as related experimental techniques, are illustrated through recent achievements with unstable nuclei.

  7. Maruhn-Greiner Maximum for Confirmation of Low Energy Nuclear Reactions (LENR) via a Compound Nucleus with Double Magic Numbers

    NASA Astrophysics Data System (ADS)

    Hora, Heinrich; Miley, George

    2007-03-01

    One of the most convincing facts about LENR due to deuterons (ds) or protons of very high concentration in host metals of palladium is the measurement of the large scale minimum in the reaction probability with product elements centered around the nucleon number A = 153. The local maximum was measured in this region is similar to fission of uranium at A = 119 where the local maximum follows the Maruhn-Greiner mechanism^1. We suggest this phenomenon can be explained by the strong screening of the Maxwellian ds on the degenerate rigid electron background within the swimming electrons at the metal surface or thin filem interfaces. The deuterons behave like neutrals at distances of above 2 picometers (pm) and form clusters due to soft attraction in the range of thermal energy; 10 pm diameter clusters can react over long time scales (10^6 s) with Pd leading to double magic number compound nuclei 306x126 decaying via fission to an A=153 element distribution. J. Maruhn et al, Phys. Rev. Letters 32, 548 (1974) H. Hora, G.H. Miley, CzechJ. Phys. 48, 1111 (1998)

  8. Multilayer Network Analysis of Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Zhu, Liang; Ma, Yu-Gang; Chen, Qu; Han, Ding-Ding

    2016-08-01

    The nuclear reaction network is usually studied via precise calculation of differential equation sets, and much research interest has been focused on the characteristics of nuclides, such as half-life and size limit. In this paper, however, we adopt the methods from both multilayer and reaction networks, and obtain a distinctive view by mapping all the nuclear reactions in JINA REACLIB database into a directed network with 4 layers: neutron, proton, 4He and the remainder. The layer names correspond to reaction types decided by the currency particles consumed. This combined approach reveals that, in the remainder layer, the β-stability has high correlation with node degree difference and overlapping coefficient. Moreover, when reaction rates are considered as node strength, we find that, at lower temperatures, nuclide half-life scales reciprocally with its out-strength. The connection between physical properties and topological characteristics may help to explore the boundary of the nuclide chart.

  9. Multilayer Network Analysis of Nuclear Reactions.

    PubMed

    Zhu, Liang; Ma, Yu-Gang; Chen, Qu; Han, Ding-Ding

    2016-08-25

    The nuclear reaction network is usually studied via precise calculation of differential equation sets, and much research interest has been focused on the characteristics of nuclides, such as half-life and size limit. In this paper, however, we adopt the methods from both multilayer and reaction networks, and obtain a distinctive view by mapping all the nuclear reactions in JINA REACLIB database into a directed network with 4 layers: neutron, proton, (4)He and the remainder. The layer names correspond to reaction types decided by the currency particles consumed. This combined approach reveals that, in the remainder layer, the β-stability has high correlation with node degree difference and overlapping coefficient. Moreover, when reaction rates are considered as node strength, we find that, at lower temperatures, nuclide half-life scales reciprocally with its out-strength. The connection between physical properties and topological characteristics may help to explore the boundary of the nuclide chart.

  10. Multilayer Network Analysis of Nuclear Reactions

    PubMed Central

    Zhu, Liang; Ma, Yu-Gang; Chen, Qu; Han, Ding-Ding

    2016-01-01

    The nuclear reaction network is usually studied via precise calculation of differential equation sets, and much research interest has been focused on the characteristics of nuclides, such as half-life and size limit. In this paper, however, we adopt the methods from both multilayer and reaction networks, and obtain a distinctive view by mapping all the nuclear reactions in JINA REACLIB database into a directed network with 4 layers: neutron, proton, 4He and the remainder. The layer names correspond to reaction types decided by the currency particles consumed. This combined approach reveals that, in the remainder layer, the β-stability has high correlation with node degree difference and overlapping coefficient. Moreover, when reaction rates are considered as node strength, we find that, at lower temperatures, nuclide half-life scales reciprocally with its out-strength. The connection between physical properties and topological characteristics may help to explore the boundary of the nuclide chart. PMID:27558995

  11. Multilayer Network Analysis of Nuclear Reactions.

    PubMed

    Zhu, Liang; Ma, Yu-Gang; Chen, Qu; Han, Ding-Ding

    2016-01-01

    The nuclear reaction network is usually studied via precise calculation of differential equation sets, and much research interest has been focused on the characteristics of nuclides, such as half-life and size limit. In this paper, however, we adopt the methods from both multilayer and reaction networks, and obtain a distinctive view by mapping all the nuclear reactions in JINA REACLIB database into a directed network with 4 layers: neutron, proton, (4)He and the remainder. The layer names correspond to reaction types decided by the currency particles consumed. This combined approach reveals that, in the remainder layer, the β-stability has high correlation with node degree difference and overlapping coefficient. Moreover, when reaction rates are considered as node strength, we find that, at lower temperatures, nuclide half-life scales reciprocally with its out-strength. The connection between physical properties and topological characteristics may help to explore the boundary of the nuclide chart. PMID:27558995

  12. MEANS FOR TERMINATING NUCLEAR REACTIONS

    DOEpatents

    Cooper, C.M.

    1959-02-17

    An apparatus is presented for use in a reactor of the heterogeneous, fluid cooled type for the purpose of quickly terminating the reaction, the coolant being circulated through coolant tubes extending through the reactor core. Several of the tubes in the critical region are connected through valves to a tank containing a poisoning fluid having a high neutron capture crosssection and to a reservoir. When it is desired to quickly terminate the reaction, the valves are operated to permit the flow of the poisoning fluid through these particular tubes and into the reservoir while normal coolant is being circulated through the remaining tubes. The apparatus is designed to prevent contamination of the primary coolant by the poisoning fluid.

  13. Nuclear Energy and the Environment.

    ERIC Educational Resources Information Center

    International Atomic Energy Agency, Vienna (Austria).

    "Nuclear Energy and the Environment" is a pocket folder of removable leaflets concerned with two major topics: Nuclear energy and Nuclear Techniques. Under Nuclear Energy, leaflets concerning the topics of "Radiation--A Fact of Life,""The Impact of a Fact: 1963 Test Ban Treaty,""Energy Needs and Nuclear Power,""Power Reactor Safety,""Transport,"…

  14. Quark catalysis of exothermal nuclear reactions.

    PubMed

    Zweig, G

    1978-09-15

    This article discusses circumstances under which free quarks catalyze exothermal nuclear reactions. It also presents possible methods for removing quarks sequestered by nuclear reaction products. Stable quarks that are negatively charged and significantly heavier than electrons attract positively charged nuclei to form new states of matter. The nuclei and quarks are closely bound, and presumably interact through both electromagnetic and nuclear forces. Nuclear fusion and fission are possible, as well as a new class of plural reactions in which either a quark isobar, isotope, or isotone is created in each individual reaction, with catalysis resulting in the overall system because the net transfer of charge, neutrons, or protons to the quarks is zero. The quark with quantum numbers of üü is a promising catalytic candidate. A satisfactory understanding of which reactions are or are not possible awaits the isolation of free quarks and a description of their strong interactions with matter. Finally, other kinds of stable negatively charged particles (such as heavy leptons), if discovered, can catalyze deuterium fusion reactions if thermal neutrons are used to liberate He(3)-bound catalytic particles. PMID:17743618

  15. Generation of Gravitational Waves with Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Fontana, Giorgio; Baker, Robert M. L.

    2006-01-01

    The problem of efficient generation of High Frequency Gravitational Waves (HFGWs) and pulses of Gravitational Radiation might find a reasonably simple solution by employing nuclear matter, especially isomers. A fissioning isomer not only rotates at extremely high frequency (~ 3.03×1024 s-1), but is also highly deformed in the first stages of fission (the nucleus is rotating and made asymmetric ``before'' fission). Thus one achieves significant impulsive forces (e.g., 3.67×108 N) acting over extremely short time spans (e.g., 3.3×10-22 s). Alternatively, a pulsed particle beam, which could include antimatter, could trigger nuclear reactions and build up a coherent GW as the particles move through a target mass. The usual difficulty with HFGWs generated by nuclear reactions is the small dimensions of their nuclear-reaction volumes, that is, the small moment of inertia and submicroscopic radii of gyration (e.g., 10-16 m) of the nuclear-mass system. Such a difficulty is overcome by utilizing clusters of nuclear material, whose nuclear reactions are in synchronization (through the use of a computer controlled logic system) and are at a large distance apart, e.g., meters, kilometers, etc. The effective radius of gyration of the overall nuclear mass system is enormous and if the quadrupole formalism holds even approximately, then significant HFGW is generated, for example up to 8.5×1010 W to 1.64×1025 W bursts for the transient asymmetrical spinning nucleus case. In this preliminary analysis, possible conceptual designs of reactors suitable for the generation of HFGWs are discussed as well as applications to space technology. In an optimized dual-beam design, GW amplitudes on the order of A ~ 0.005 are theoretically achieved in the laboratory, which might have interesting general-relativity and nuclear-physics consequences.

  16. Desalting and Nuclear Energy

    ERIC Educational Resources Information Center

    Burwell, Calvin C.

    1971-01-01

    Future use of nuclear energy to produce electricity and desalted water is outlined. Possible desalting processes are analyzed to show economic feasibility and the place in planning in world's economic growth. (DS)

  17. US nuclear reaction data program in support of basic research

    SciTech Connect

    Bhat, M.R.; Chadwick, M.B.; Smith, M.S.

    1997-06-01

    Information about the US Nuclear Reaction Data Network (USNRDN) such as its members, work in progress, summaries of meetings, and organizational details may be found in its WWW Homepage. This paper is an overview of the data support provided by the network for basic research in nuclear astrophysics, radioactive ion beams, high energy heavy-ion and electron interactions and related activities involving all aspects of data stewardship.

  18. The Nuclear Reactions in Standard BBN

    NASA Astrophysics Data System (ADS)

    Serpico, Pasquale D.

    2005-07-01

    Nowadays, the Cosmic Microwave Background (CMB) anisotropy studies accurately determine the baryon fraction ω showing an overall and striking agreement with previous determinations of ω obtained from Big Bang Nucleosynthesis (BBN). However, a deeper comparison of BBN predictions with the determinations of the primordial light nuclide abundances shows some tension, motivating an effort to further improve the accuracy of theoretical predictions, as well as to better evaluate systematics in both observations and nuclear reactions measurements. We present some results of an important step towards an increasing precision of BBN predictions, namely an updated and critical review of the nuclear network, and a new protocol to perform the nuclear data regression.

  19. Tailoring medium energy proton beam to induce low energy nuclear reactions in ⁸⁶SrCl₂ for production of PET radioisotope ⁸⁶Y.

    PubMed

    Medvedev, Dmitri G; Mausner, Leonard F; Pile, Philip

    2015-07-01

    This paper reports results of experiments at Brookhaven Linac Isotope Producer (BLIP) aiming to investigate effective production of positron emitting radioisotope (86)Y by the low energy (86)Sr(p,n) reaction. BLIP is a facility at Brookhaven National Laboratory designed for the proton irradiation of the targets for isotope production at high and intermediate proton energies. The proton beam is delivered by the Linear Accelerator (LINAC) whose incident energy is tunable from 200 to 66 MeV in approximately 21 MeV increments. The array was designed to ensure energy degradation from 66 MeV down to less than 20 MeV. Aluminum slabs were used to degrade the proton energy down to the required range. The production yield of (86)Y (1.2+/-0.1 mCi (44.4+/-3.7) MBq/μAh) and ratio of radioisotopic impurities was determined by assaying an aliquot of the irradiated (86)SrCl2 solution by gamma spectroscopy. The analysis of energy dependence of the (86)Y production yield and the ratios of radioisotopic impurities has been used to adjust degrader thickness. Experimental data showed substantial discrepancies in actual energy propagation compared to energy loss calculations.

  20. Towards a More Complete and Accurate Experimental Nuclear Reaction Data Library (EXFOR). International Collaboration Between Nuclear Reaction Data Centres (NRDC)

    SciTech Connect

    Otuka, N.; Pritychenko, B.; Otuka, N.; Dupont, E.; Semkova, V.; Pritychenko, B.; Blokhin, A. I.; Aikawa, M.; Babykina, S.; Bossant, M.; Chen, G.; Dunaeva, S.; Forrest, R. A.; Fukahori, T.; Furutachi, N.; Ganesan, S.; Ge, Z.; Gritzay, O. O.; Herman, M.; Hlavac, S.; Kato, K.; Lalremruata, B.; Lee, Y. O.; Makinaga, A.; Matsumoto, K.; Mikhaylyukova, M.; Pikulina, G.; Pronyaev, V. G.; Saxena, A.; Schwerer, O.; Simakov, S. P.; Soppera, N.; Suzuki, R.; Takacs, S.; Tao, X.; Taova, S.; Tarkanyi, F.; Varlamov, V. V.; Wang, J.; Yang, S. C.; Zerkin, V.; Zhuang, Y.

    2014-06-01

    The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by the IAEA Nuclear Data Section (NDS) successfully collaborates in the maintenance and development of the EXFOR library. Likewise, as the scope of published data expands (e.g. to higher energy, to heavier projectile) to meet the needs of research and applications, it has become a challenging task to maintain both the completeness and accuracy of the EXFOR library. Evolution of the library highlighting recent developments is described.

  1. Towards a More Complete and Accurate Experimental Nuclear Reaction Data Library (EXFOR): International Collaboration Between Nuclear Reaction Data Centres (NRDC)

    SciTech Connect

    Otuka, N.; Dupont, E.; Semkova, V.; Pritychenko, B.; Blokhin, A.I.; Aikawa, M.; Babykina, S.; Bossant, M.; Chen, G.; Dunaeva, S.; Forrest, R.A.; Fukahori, T.; Furutachi, N.; Ganesan, S.; Ge, Z.; Gritzay, O.O.; Herman, M.; Hlavač, S.; and others

    2014-06-15

    The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by the IAEA Nuclear Data Section (NDS) successfully collaborates in the maintenance and development of the EXFOR library. As the scope of published data expands (e.g. to higher energy, to heavier projectile) to meet the needs of research and applications, it has become a challenging task to maintain both the completeness and accuracy of the EXFOR library. Evolution of the library highlighting recent developments is described.

  2. Nuclear reactions for nucleosynthesis beyond Fe

    SciTech Connect

    Rauscher, Thomas

    2015-10-15

    Many more nuclear transitions have to be known in the determination of stellar reactivities for trans-iron nucleosynthesis than for reactions of light nuclei. This requires different theoretical and experimental approaches. Some of the issues specific for trans-iron nucleosynthesis are discussed.

  3. Studying Nuclear Level Densities of 238U in the Nuclear Reactions within the Macroscopic Nuclear Models

    NASA Astrophysics Data System (ADS)

    Razavi, Rohallah; Rahmatinejad, Azam; Kakavand, Tayeb; Taheri, Fariba; Aghajani, Maghsood; Khooy, Asghar

    2016-02-01

    In this work the nuclear level density parameters of 238U have been extracted in the back-shifted Fermi gas model (BSFGM), as well as the constant temperature model (CTM), through fitting with the recent experimental data on nuclear level densities measured by the Oslo group. The excitation functions for 238U(p,2nα)233Pa, and 238U(p,4n)235Np reactions and the fragment yields for the fragments of the 238U(p,f) reaction have been calculated using obtained level density parameters. The results are compared to their corresponding experimental values. It was found that the extracted excitation functions and the fragment yields in the CTM coincide well with the experimental values in the low-energy region. This finding is according to the claim made by the Oslo group that the extracted level densities of 238U show a constant temperature behaviour.

  4. Low-energy proton capture reactions

    SciTech Connect

    Lipoglavsek, M.; Cvetinovic, A.; Gajevic, J.; Likar, A.; Vavpetic, P.; Petrovic, T.

    2014-05-09

    An overview of experimental problems in measuring the cross sections for (p,γ) and (p,n) reactions at low energies is given with a specific emphasis on electron screening in metallic targets. Thick target γ-ray and neutron yields are compared for Ni and NiO targets, V and VO{sub 2} targets and Mn and MnO targets. The {sup 1}H({sup 7}Li,α){sup 4}He reaction was studied in inverse kinematics with hydrogen loaded into Pd and PdAg alloy foils from gas phase. Based on these results, a new approach to electron screening in nuclear reactions is suggested.

  5. Excitation function calculations for α + 93Nb nuclear reactions

    NASA Astrophysics Data System (ADS)

    Yiǧit, M.; Tel, E.; Sarpün, İ. H.

    2016-10-01

    In this study, the excitation functions of alpha-induced reactions on the 93Nb target nucleus were calculated by using ALICE-ASH code. The hybrid model, Weisskopf-Ewing model and geometry dependent hybrid model in this code were used to understand the alpha-niobium interaction. The contribution on the nuclear interaction of compound and pre-compound processes, with variation of the incident alpha particle energy, was presented. Furthermore, the reaction cross sections were calculated by using different level density models such as Superfluid nuclear model, Fermi gas model and Kataria-Ramamurthy Fermi gas model. Obtaining a good agreement between the calculated and the measured cross sections, the exciton numbers and the nuclear level density models were varied. Finally, the proper choice of the exciton numbers and the nuclear level density models was found to be quite important in order to obtain the more realistic cross section values.

  6. Excitation functions of (nat)Zn(p,x) nuclear reactions with proton beam energy below 18 MeV.

    PubMed

    Asad, Ali H; Chan, Sun; Morandeau, Laurence; Cryer, David; Smith, Suzanne V; Price, Roger I

    2014-12-01

    We measured the excitation functions of (nat)Zn (p,x) reactions up to 17.6MeV, using the stacked-foils activation technique. High-purity natural zinc (and copper) foils were irradiated with proton beams generated by an 18MeV isochronous cyclotron. Activated foils were measured using high-purity Ge gamma spectroscopy to quantify the radionuclides (61)Cu, (66)Ga, (67)Ga, and (65)Zn produced from the reactions. Thick-target integral yields were also deduced from the measured excitation functions of the produced radioisotopes. These results were compared with the published literature and were found to be in good agreement with most reports, particularly those most recently compiled.

  7. Nuclear Structure and Reaction Mechanism Studies with Multinucleon Reactions

    SciTech Connect

    Regan, P. H.; Jones, G. A.; Podolyak, Zs.; Abdullah, M.; Gelletly, W.; Langdown, S. D.; Wollel, G.; De Angelis, G.; Gadea, A.; Kroell, Th.; Marginean, N.; Martinez, T.; Napoli, D. R.; Rusu, C.; Tonev, D.; Zhang, Y. H.; Ur, C. A.; Axiotis, M.; Bazzacco, D.; Farnea, E.

    2006-08-14

    This contribution reports on the results of an experiment to study the near-yrast states in selenium- and osmium-like nuclei, following their population in thick-target, multinucleon transfer reactions between an 82Se beam and a 192Os target. The experimental results for the level scheme for 84Se are presented together with investigations into the use of multi-dimensional gamma-ray energy gating to investigate angular momentum population in such heavy-ion binary reactions.

  8. Advances in Nuclear Energy

    NASA Astrophysics Data System (ADS)

    Frois, B.

    2005-04-01

    This paper briefly reviews the next generations of nuclear reactors and the perspectives of development of nuclear energy. Advanced reactors will progressively replace the existing ones during the next two decades. Future systems of the fourth generation are planned to be built beyond 2030. These systems have been studied in the framework of the "Generation IV" International Forum. The goals of these systems is to have a considerable increase in safety, be economically competitive and produce a significantly reduced volume of nuclear wastes. The closed fuel cycle is preferred.

  9. Nuclear hybrid energy infrastructure

    SciTech Connect

    Agarwal, Vivek; Tawfik, Magdy S.

    2015-02-01

    The nuclear hybrid energy concept is becoming a reality for the US energy infrastructure where combinations of the various potential energy sources (nuclear, wind, solar, biomass, and so on) are integrated in a hybrid energy system. This paper focuses on challenges facing a hybrid system with a Small Modular Reactor at its core. The core of the paper will discuss efforts required to develop supervisory control center that collects data, supports decision-making, and serves as an information hub for supervisory control center. Such a center will also be a model for integrating future technologies and controls. In addition, advanced operations research, thermal cycle analysis, energy conversion analysis, control engineering, and human factors engineering will be part of the supervisory control center. Nuclear hybrid energy infrastructure would allow operators to optimize the cost of energy production by providing appropriate means of integrating different energy sources. The data needs to be stored, processed, analyzed, trended, and projected at right time to right operator to integrate different energy sources.

  10. Neutrino-induced Reactions and Neutrino Scattering with Nuclear Targets

    NASA Astrophysics Data System (ADS)

    Cheoun, Myung-Ki; Ha, Eunja; Yang, Ghil-Seok; Kim, Kyungsik; Kajino, T.

    2016-02-01

    We reviewed present status regarding experimental data and theoretical approaches for neutrino-induced reactions and neutrino scattering. With a short introduction of relevant data, our recent calculations by distorted-wave Born approximation for quasielastic region are presented for MiniBooNE data. For much higher energy neutrino data, such as NOMAD data, elementary process approach was shown to be useful instead of using complicated nuclear models. But, in the low energy region, detailed nuclear structure model, such as QRPA and shell model, turn out to be inescapable to explain the reaction data. Finally, we discussed that one step-process in the reaction is comparable to the two-step process, which has been usually used in the neutrino-nucleosynthesis.

  11. Nuclear reactions used for superheavy element research

    SciTech Connect

    Stoyer, M A

    2008-02-26

    Some of the most fascinating questions about the limits of nuclear stability are confronted in the heaviest nuclei. How many more new elements can be synthesized? What are the nuclear and chemical properties of these exotic nuclei? Does the 'Island of Stability' exist and can we ever explore the isotopes inhabiting that nuclear region? This paper will focus on the current experimental research on the synthesis and characterization of superheavy nuclei with Z > 112 from the Dubna/Livermore collaboration. Reactions using 48Ca projectiles from the U400 cyclotron and actinide targets ({sup 233,238}U, {sup 237}Np, {sup 242,244}Pu, {sup 243}Am, {sup 245,248}Cm, {sup 249}Cf) have been investigated using the Dubna Gas Filled Recoil Separator in Dubna over the last 8 years. In addition, several experiments have been performed to investigate the chemical properties of some of the observed longer-lived isotopes produced in these reactions. Some comments will be made on nuclear reactions used for the production of the heaviest elements. A summary of the current status of the upper end of the chart of nuclides will be presented.

  12. Nuclear Reactions in Micro/Nano-Scale Metal Particles

    NASA Astrophysics Data System (ADS)

    Kim, Y. E.

    2013-03-01

    Low-energy nuclear reactions in micro/nano-scale metal particles are described based on the theory of Bose-Einstein condensation nuclear fusion (BECNF). The BECNF theory is based on a single basic assumption capable of explaining the observed LENR phenomena; deuterons in metals undergo Bose-Einstein condensation. The BECNF theory is also a quantitative predictive physical theory. Experimental tests of the basic assumption and theoretical predictions are proposed. Potential application to energy generation by ignition at low temperatures is described. Generalized theory of BECNF is used to carry out theoretical analyses of recently reported experimental results for hydrogen-nickel system.

  13. Nucleus Z=126 with magic neutron number N=184 may be related to the measured Maruhn-Greiner maximum at A/2=155 from compound nuclei at low energy nuclear reactions

    NASA Astrophysics Data System (ADS)

    Prelas, M. A.; Hora, H.; Miley, G. H.

    2014-07-01

    Evaluation of nuclear binding energies from theory close to available measurements of a very high number of superheavy elements (SHE) based on α-decay energies Qα, arrived at a closing shell with a significant neutron number 184. Within the option of several discussed magic numbers for protons of around 120, Bagge's numbers 126 and 184 fit well and are supported by the element generation measurements by low energy nuclear reactions (LENR) discovered in deuterium loaded host metals. These measurements were showing a Maruhn-Greiner maximum from fission of compound nuclei in an excited state with double magic numbers for mutual confirmation.

  14. Intermediate-energy nuclear chemistry workshop

    SciTech Connect

    Butler, G.W.; Giesler, G.C.; Liu, L.C.; Dropesky, B.J.; Knight, J.D.; Lucero, F.; Orth, C.J.

    1981-05-01

    This report contains the proceedings of the LAMPF Intermediate-Energy Nuclear Chemistry Workshop held in Los Alamos, New Mexico, June 23-27, 1980. The first two days of the Workshop were devoted to invited review talks highlighting current experimental and theoretical research activities in intermediate-energy nuclear chemistry and physics. Working panels representing major topic areas carried out indepth appraisals of present research and formulated recommendations for future research directions. The major topic areas were Pion-Nucleus Reactions, Nucleon-Nucleus Reactions and Nuclei Far from Stability, Mesonic Atoms, Exotic Interactions, New Theoretical Approaches, and New Experimental Techniques and New Nuclear Chemistry Facilities.

  15. Microscopic time-dependent analysis of neutrons transfers at low-energy nuclear reactions with spherical and deformed nuclei

    NASA Astrophysics Data System (ADS)

    Samarin, Viacheslav

    2014-03-01

    Time-dependent Schrödinger equation is numerically solved by difference method for external neutrons of nuclei 6He, 18O, 48Са, 238U at their grazing collisions with energies in the vicinity of a Coulomb barrier. The spin-orbital interaction and Pauli's exclusion principle were taken into consideration during the solution.

  16. Approximate penetration factors for nuclear reactions of astrophysical interest

    NASA Technical Reports Server (NTRS)

    Humblet, J.; Fowler, W. A.; Zimmerman, B. A.

    1987-01-01

    The ranges of validity of approximations of P(l), the penetration factor which appears in the parameterization of nuclear-reaction cross sections at low energies and is employed in the extrapolation of laboratory data to even lower energies of astrophysical interest, are investigated analytically. Consideration is given to the WKB approximation, P(l) at the energy of the total barrier, approximations derived from the asymptotic expansion of G(l) for large eta, approximations for small values of the parameter x, applications of P(l) to nuclear reactions, and the dependence of P(l) on channel radius. Numerical results are presented in tables and graphs, and parameter ranges where the danger of serious errors is high are identified.

  17. Solving The Long-Standing Problem Of Low-Energy Nuclear Reactions At The Highest Microscopic Level. Annual Continuation And Progress Report, August 15, 2014 -- August 14, 2015

    SciTech Connect

    Quaglioni, Sofia

    2015-03-19

    The aim of this project is to develop a comprehensive framework that will lead to a fundamental description of both structural properties and reactions of light nuclei in terms of constituent protons and neutrons interacting through nucleon-nucleon (NN) and three-nucleon (3N) forces. This project will provide the research community with the theoretical and computational tools what will enable: an accurate prediction for fusion reactions that power stars and Earth-based fusion facilities; an improved description of the spectroscopy of exotic nuclei, including light Borromean systems; and, a fundamental understanding of the three-nucleon force in nuclear reaction and nuclei at the drip line.

  18. Direct reactions for nuclear structure required for fundamental symmetry tests

    NASA Astrophysics Data System (ADS)

    Garrett, P. E.; Rand, E. T.; Diaz Varela, A.; Ball, G. C.; Bildstein, V.; Faestermann, T.; Hadinia, B.; Hertenberger, R.; Jamieson, D. S.; Jigmeddorj, B.; Leach, K. G.; Svensson, C. E.; Wirth, H.-F.

    2016-09-01

    A program of nuclear structure studies to support fundamental symmetry tests has been initiated. Motivated by the search for an electric dipole moment in 199Hg, the structure in the vicinity has been explored via direct reaction studies. To date, these have included the 198,200Hg(d, d') inelastic scattering reactions, with the aim to obtain information on the E2 and E3 strength distributions, and the 198Hg(d, p) and 200Hg(d, t) reactions to obtain information on the single-particle states in 199Hg. The studies using the 200Hg targets have been fully analyzed using the FRESCO reaction code yielding the E2 and E3 strength distribution to 4 MeV in excitation energy, and the (d, t) single- particle strength to over 3 MeV in excitation energy.

  19. A Transport Model for Nuclear Reactions Induced by Radioactive Beams

    SciTech Connect

    Li Baoan; Chen Liewen; Das, Champak B.; Das Gupta, Subal; Gale, Charles; Ko, C.M.; Yong, G.-C.; Zuo Wei

    2005-10-14

    Major ingredients of an isospin and momentum dependent transport model for nuclear reactions induced by radioactive beams are outlined. Within the IBUU04 version of this model we study several experimental probes of the equation of state of neutron-rich matter, especially the density dependence of the nuclear symmetry energy. Comparing with the recent experimental data from NSCL/MSU on isospin diffusion, we found a nuclear symmetry energy of Esym({rho}) {approx_equal} 31.6({rho}/{rho}0)1.05 at subnormal densities. Predictions on several observables sensitive to the density dependence of the symmetry energy at supranormal densities accessible at GSI and the planned Rare Isotope Accelerator (RIA) are also made.

  20. Public reactions to nuclear waste: Citizens' views of repository siting

    SciTech Connect

    Rosa, E.A.

    1993-01-01

    This book presents revised and updated papers from a panel of social scientists, at the 1989 AAAS meetings, that examined the public's reactions to nuclear waste disposal and the repository siting process. The papers report the results of original empirical research on citizens' views of nuclear waste repository siting. Topics covered include the following: content analysis of public testimony; sources of public concern about nuclear waste disposal in Texas agricultural communities; local attitudes toward high-level waste repository at Hanford; perceived risk and attitudes toward nuclear wastes; attitudes of Nevada urban residents toward a nuclear waste repository; attitudes of rural community residents toward a nuclear waste respository. An introductory chapter provides background and context, and a concluding chapter summarizes the implications of the reports. Two additional chapters cover important features of high-level waste disposal: long term trends in public attitudes toward nuclear energy and nuclear waste policy and assessment of the effects on the Los Vegas convention business if a high-level nuclear waste depository were sited in Nevada.

  1. Random matrices and chaos in nuclear physics: Nuclear reactions

    SciTech Connect

    Mitchell, G. E.; Richter, A.; Weidenmueller, H. A.

    2010-10-15

    The application of random-matrix theory (RMT) to compound-nucleus (CN) reactions is reviewed. An introduction into the basic concepts of nuclear scattering theory is followed by a survey of phenomenological approaches to CN scattering. The implementation of a random-matrix approach into scattering theory leads to a statistical theory of CN reactions. Since RMT applies generically to chaotic quantum systems, that theory is, at the same time, a generic theory of quantum chaotic scattering. It uses a minimum of input parameters (average S matrix and mean level spacing of the CN). Predictions of the theory are derived with the help of field-theoretical methods adapted from condensed-matter physics and compared with those of phenomenological approaches. Thorough tests of the theory are reviewed, as are applications in nuclear physics, with special attention given to violation of symmetries (isospin and parity) and time-reversal invariance.

  2. Effect of nuclear-reaction mechanisms on the population of excited nuclear states and isomeric ratios

    NASA Astrophysics Data System (ADS)

    Skobelev, N. K.

    2016-07-01

    Experimental data on the cross sections for channels of fusion and transfer reactions induced by beams of radioactive halo nuclei and clustered and stable loosely bound nuclei were analyzed, and the results of this analysis were summarized. The interplay of the excitation of single-particle states in reaction-product nuclei and direct reaction channels was established for transfer reactions. Respective experiments were performed in stable (6Li) and radioactive (6He) beams of the DRIBs accelerator complex at the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, and in deuteron and 3He beams of the U-120M cyclotron at the Nuclear Physics Institute, Academy Sciences of Czech Republic (Řež and Prague, Czech Republic). Data on subbarrier and near-barrier fusion reactions involving clustered and loosely bound light nuclei (6Li and 3He) can be described quite reliably within simple evaporation models with allowance for different reaction Q-values and couple channels. In reactions involving halo nuclei, their structure manifests itself most strongly in the region of energies below the Coulomb barrier. Neutron transfer occurs with a high probability in the interactions of all loosely bound nuclei with light and heavy stable nuclei at positive Q-values. The cross sections for such reactions and the respective isomeric ratios differ drastically for nucleon stripping and nucleon pickup mechanisms. This is due to the difference in the population probabilities for excited single-particle states.

  3. Visualized kinematics code for two-body nuclear reactions

    NASA Astrophysics Data System (ADS)

    Lee, E. J.; Chae, K. Y.

    2016-05-01

    The one or few nucleon transfer reaction has been a great tool for investigating the single-particle properties of a nucleus. Both stable and exotic beams are utilized to study transfer reactions in normal and inverse kinematics, respectively. Because many energy levels of the heavy recoil from the two-body nuclear reaction can be populated by using a single beam energy, identifying each populated state, which is not often trivial owing to high level-density of the nucleus, is essential. For identification of the energy levels, a visualized kinematics code called VISKIN has been developed by utilizing the Java programming language. The development procedure, usage, and application of the VISKIN is reported.

  4. From Stopping to Viscosity in Nuclear Reactions

    SciTech Connect

    Danielewicz, Pawel; Barker, Brent; Shi Lijun

    2009-05-07

    Data on stopping in intermediate-energy central heavy-ion collisions are analyzed following transport theory based on the Boltzmann equation. In consequence, values of nuclear shear viscosity are inferred. The inferred values are significantly larger than obtained for free nucleon dispersion relations and free nucleon-nucleon cross sections.

  5. A Career in Nuclear Energy

    ScienceCinema

    Lambregts, Marsha

    2016-07-12

    Nuclear chemist Dr. Marsha Lambregts talks about the Center for Advanced Energy Studies and the benefits of a nuclear energy career. For more information about careers at INL, visit http://www.facebook.com/idahonationallaboratory.

  6. A Career in Nuclear Energy

    SciTech Connect

    Lambregts, Marsha

    2009-01-01

    Nuclear chemist Dr. Marsha Lambregts talks about the Center for Advanced Energy Studies and the benefits of a nuclear energy career. For more information about careers at INL, visit http://www.facebook.com/idahonationallaboratory.

  7. Sigma: Web Retrieval Interface for Nuclear Reaction Data

    SciTech Connect

    Pritychenko,B.; Sonzogni, A.A.

    2008-06-24

    The authors present Sigma, a Web-rich application which provides user-friendly access in processing and plotting of the evaluated and experimental nuclear reaction data stored in the ENDF-6 and EXFOR formats. The main interface includes browsing using a periodic table and a directory tree, basic and advanced search capabilities, interactive plots of cross sections, angular distributions and spectra, comparisons between evaluated and experimental data, computations between different cross section sets. Interactive energy-angle, neutron cross section uncertainties plots and visualization of covariance matrices are under development. Sigma is publicly available at the National Nuclear Data Center website at www.nndc.bnl.gov/sigma.

  8. Sigma: Web Retrieval Interface for Nuclear Reaction Data

    SciTech Connect

    Pritychenko, B. Sonzogni, A.A.

    2008-12-15

    We present Sigma, a Web-rich application which provides user-friendly access in processing and plotting of the evaluated and experimental nuclear reaction data stored in the ENDF-6 and EXFOR formats. The main interface includes browsing using a periodic table and a directory tree, basic and advanced search capabilities, interactive plots of cross sections, angular distributions and spectra, comparisons between evaluated and experimental data, computations between different cross section sets. Interactive energy-angle, neutron cross section uncertainties plots and visualization of covariance matrices are under development. Sigma is publicly available at the National Nuclear Data Center website at (http://www.nndc.bnl.gov/sigma)

  9. Opportunities in nuclear structure and reactions

    NASA Astrophysics Data System (ADS)

    Nunes, Filomena

    2015-10-01

    The last decade has seen important advances in the area of low energy nuclear physics. New measurements have provided crucial insight into the behavior of nuclei at the limits of stability, including the mapping of the neutron dripline up to Oxygen, investigations of unbound nuclear states, and the discovery of new super-heavy elements. In parallel we have seen a revolution in low-energy nuclear theory, moving toward quantified predictability, rooted in the underlying inter-nucleon forces. But the next decade offers even more opportunities with a new generation factory of rare isotopes, and the anticipated developments in high performance computing. The Facility for Rare Isotope Beams coupled with new state-of-the-art detectors will allow us to access a large fraction of the necessary information for the r-process responsible for making at least half of the heavy elements in our universe. FRIB will provide the needed intensities to study global nuclear properties, shell structure, and collective phenomena far from stability. Key measurements are anticipated, at various facilities, which will inform symmetry tests with rare isotopes. We expect to put strict constraints on the equation of state. These and many other opportunities will be highlighted in this overview talk.

  10. BRUSLIB and NETGEN: the Brussels nuclear reaction rate library and nuclear network generator for astrophysics

    NASA Astrophysics Data System (ADS)

    Aikawa, M.; Arnould, M.; Goriely, S.; Jorissen, A.; Takahashi, K.

    2005-10-01

    Nuclear reaction rates are quantities of fundamental importance in astrophysics. Substantial efforts have been devoted in the last decades to measuring or calculating them. This paper presents a detailed description of the Brussels nuclear reaction rate library BRUSLIB and of the nuclear network generator NETGEN. BRUSLIB is made of two parts. The first one contains the 1999 NACRE compilation based on experimental data for 86 reactions with (mainly) stable targets up to Si. BRUSLIB provides an electronic link to the published, as well as to a large body of unpublished, NACRE data containing adopted rates, as well as lower and upper limits. The second part of BRUSLIB concerns nuclear reaction rate predictions to complement the experimentally-based rates. An electronic access is provided to tables of rates calculated within a statistical Hauser-Feshbach approximation, which limits the reliability of the rates to reactions producing compound nuclei with a high enough level density. These calculations make use of global and coherent microscopic nuclear models for the quantities entering the rate calculations. The use of such models makes the BRUSLIB rate library unique. A description of the Nuclear Network Generator NETGEN that complements the BRUSLIB package is also presented. NETGEN is a tool to generate nuclear reaction rates for temperature grids specified by the user. The information it provides can be used for a large variety of applications, including Big Bang nucleosynthesis, the energy generation and nucleosynthesis associated with the non-explosive and explosive hydrogen to silicon burning stages, or the synthesis of the heavy nuclides through the s-, α- and r-, rp- or p-processes.

  11. Extension of the energy range of the experimental activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium up to 65MeV.

    PubMed

    Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

    2015-04-01

    Activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium were extended up to 65MeV by using stacked foil irradiation and gamma spectrometry experimental methods. Experimental cross-sections data for the formation of the radionuclides (159)Dy, (157)Dy, (155)Dy, (161)Tb, (160)Tb, (156)Tb, (155)Tb, (154m2)Tb, (154m1)Tb, (154g)Tb, (153)Tb, (152)Tb and (151)Tb are reported in the 36-65MeV energy range, and compared with an old dataset from 1964. The experimental data were also compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction model code as listed in the latest on-line libraries TENDL 2013.

  12. NNDC PERSPECTIVE ON NUCLEAR REACTION DATABASES AND ORELA.

    SciTech Connect

    OBLOZINSKY, P.

    2005-07-14

    We discuss perspective of the National Nuclear Data Center on nuclear reaction databases, focusing on contributions from the ORELA machine over more than 3 decades. We conclude that ORELA had profound impact on nuclear reaction databases, in particular CSISRS and ENDF. In addition, ORELA contributed considerable amount of data included in the recent Atlas of Neutron Resonances, along with data of critical importance for nuclear reaction model calculations by codes such as EMPIRE.

  13. Formation of correlated states and optimization of nuclear reactions for low-energy particles at nonresonant low-frequency modulation of a potential well

    SciTech Connect

    Vysotskii, V. I. Vysotskyy, M. V.

    2015-02-15

    A method for the formation of correlated coherent states of low-energy particles in a parabolic potential well owing to the full-scale low-frequency modulation ω(t) = ω{sub 0}sinΩt of the parameters of this well has been considered. It has been shown that such a modulation in the absence of a stochastic force acting on a particle results in the fast formation of correlated coherent states and in an increase in the correlation coefficient and transparency of the potential barrier to the limiting values vertical bar r(t) vertical bar {sub max} → 1 and D → 1. The presence of the stochastic force significantly affects the evolution of correlated coherent states, decreasing the rate of an increase in the correlation coefficient vertical bar r(t) vertical bar {sub max} (at Ω ≤ 10{sup −4}ω{sub 0}) and limiting it at the level vertical bar r(∞) vertical bar {sub max} < 1 (at Ω = (0.001–0.1)ω{sub 0}); vertical bar r(∞) vertical bar {sub max} increases with a decrease in the frequency of modulation and decreases with an increase in the intensity of the stochastic force. It has been shown that, at a realistic relation between the parameters, low-frequency modulation can ensure such vertical bar r vertical bar {sub max} value that the transparency of the potential barrier for low-energy particles increases by a factor of 10{sup 50}–10{sup 100} or larger. The mechanism of the formation of correlated coherent states for charged particles in a gas or a low-pressure plasma placed in a low-frequency magnetic field has been considered. We have determined the relation between the magnetic field strength and modulation frequency, as well as the relation between the temperature and density of the gas (plasma), at which the method under consideration can be used to optimize nuclear reactions at low energies.

  14. NUCLEAR AND HEAVY ION PHYSICS: Measurement of the astrophysical S factor for the low energy 2H(d,γ)4He reaction

    NASA Astrophysics Data System (ADS)

    Zhou, Jing; Fu, Yuan-Yong; Zhou, Shu-Hua; Xia, Hai-Hong; Li, Cheng-Bo; Meng, Qiu-Ying

    2009-05-01

    The γ-rays and protons from an Ed = 20 keV deuteron beam incident on a D—Ti target were measured. A branching ratio of the 2H(d,γ)4 He reaction versus the 2H(d,p) 3H reaction of Γγ/Γp = (1.06 ± 0.34) × 10-7 has been obtained, and the astrophysical S factor of the 2H(d,γ)4 He reaction at the center of mass energy Ecm approx 7 keV of (6.0 ± 2.4) × 10-6 keV·b was deduced.

  15. Investigations of nuclear structure and nuclear reactions induced by complex projectiles

    SciTech Connect

    Sarantites, D.G.

    1990-01-01

    This report discusses research in the following areas: nuclear structure; fusion reactions near and below the barrier; incomplete fusion and fragmentation reactions; and instrumentation and analysis. (LSP).

  16. Experimental Observation of Nuclear Reactions in Palladium and Uranium

    SciTech Connect

    J. Dufour; D. Murat; X. Dufour; J. Foos

    2001-11-12

    By submitting various metals (Pd, U) containing hydrogen (from 2000 to 700 000 atoms of hydrogen for 1 000 000 atoms of the host metal) to the combined action of electrical currents and magnetic fields, we have observed a sizeable exothermal effect (from 0.1 to 8 W for 500 mg of metal used). This effect is beyond experimental errors, the energy output being typically 130 to 250{percent} of the energy input and not of chemical origin (exothermal effect in the range of 7000 MJ/mol of metal in the case of palladium and of 60 MJ/mol in the case of uranium). New chemical species also appear in the processes metals. It has been shown by a QED calculation that resonances of long lifetime (s), nuclear dimensions (fm), and low energy of formation (eV) could exist. This concept seems to look like the 'shrunken hydrogen atoms' proposed by various authors. It is indeed very different in two ways (a) being a metastable state, it needs energy to be formed (a few eV) and reverts to normal hydrogen after a few seconds, liberating back its energy of formation (it is thus not the source of the energy observed); (b) its formation can be described as the electron spin/proton nuclear spin interaction becoming first order in the lattice environment (whereas it is third order in a normal hydrogen atom). Moreover, we consider that the hydrex cannot yield a neutron because this reaction is strongly endothermic. To explain our results, we put forward the following working hypothesis: In a metal lattice and under proper conditions, the formation of such resonances (metastable state) could be favored. We propose to call them HYDREX, and we assume that they are actually formed in cold fusion (CF) and low-energy nuclear reaction (LENR) experiments. Once formed, a number of HYDREX could gather around a nucleus of the lattice to form a cluster of nuclear size and of very long life time compared to nuclear time (10{sup -22} s). In this cluster, nuclear rearrangements could take place, yielding

  17. Nuclear physics reactions of astrophysical importance

    NASA Astrophysics Data System (ADS)

    O'Malley, Patrick D.

    2012-05-01

    Understanding the origin of elements in the universe is one of the main goals of nuclear science and astrophysics today. Achieving this goal involves determining how the elements and their isotopes formed and being able to predict their abundances. At the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory (ORNL), an experimental program has been established to use transfer reactions (such as (p,d) or (d,p)) to study the properties of many nuclei important to understanding the origins of various elements. Three measurements were done to aid in the determination of the origins of different light isotopes. Big Bang Nucleosynthesis calculations, constrained by the Wilkinson Microwave Anisotropy Probe results, produce primordial 7Li abundances almost a factor of four larger than those extrapolated from observations. Since primordial 7Li is believed to be mostly produced by the beta decay of 7Be, one proposed solution to this discrepancy is a resonant enhancement of the 7Be(d, p)2α reaction rate through the 5/2+ 16.7-MeV state in 9B. The 2H(7Be,d) 7Be reaction was used to search for such a resonance; none was observed. An upper limit on the width of the proposed resonance was deduced. 19F is believed to have formed in Asymptotic Giant Branch stars, but current models cannot reproduce the observed abundances of this nucleus. One of the key reactions responsible for the creation of 19F is 15N(α,γ). Therefore, it is important to understand reactions that might destroy 15N, such as 15N(n,γ). The magnitude of the 15N( n,γ) reaction rate depends directly on the neutron spectroscopic factors of low-lying 16N levels. Currently the measured spectroscopic factors differ from those expected from theory by a factor of 2. A study has been done to resolve this discrepancy using the d( 15N,p) reaction. The spectroscopic factors were all found to be

  18. Laser-initiated primary and secondary nuclear reactions in Boron-Nitride.

    PubMed

    Labaune, C; Baccou, C; Yahia, V; Neuville, C; Rafelski, J

    2016-01-01

    Nuclear reactions initiated by laser-accelerated particle beams are a promising new approach to many applications, from medical radioisotopes to aneutronic energy production. We present results demonstrating the occurrence of secondary nuclear reactions, initiated by the primary nuclear reaction products, using multicomponent targets composed of either natural boron (B) or natural boron nitride (BN). The primary proton-boron reaction (p + (11)B → 3 α + 8.7 MeV), is one of the most attractive aneutronic fusion reaction. We report radioactive decay signatures in targets irradiated at the Elfie laser facility by laser-accelerated particle beams which we interpret as due to secondary reactions induced by alpha (α) particles produced in the primary reactions. Use of a second nanosecond laser beam, adequately synchronized with the short laser pulse to produce a plasma target, further enhanced the reaction rates. High rates and chains of reactions are essential for most applications. PMID:26882988

  19. Laser-initiated primary and secondary nuclear reactions in Boron-Nitride

    PubMed Central

    Labaune, C.; Baccou, C.; Yahia, V.; Neuville, C.; Rafelski, J.

    2016-01-01

    Nuclear reactions initiated by laser-accelerated particle beams are a promising new approach to many applications, from medical radioisotopes to aneutronic energy production. We present results demonstrating the occurrence of secondary nuclear reactions, initiated by the primary nuclear reaction products, using multicomponent targets composed of either natural boron (B) or natural boron nitride (BN). The primary proton-boron reaction (p + 11B → 3 α + 8.7 MeV), is one of the most attractive aneutronic fusion reaction. We report radioactive decay signatures in targets irradiated at the Elfie laser facility by laser-accelerated particle beams which we interpret as due to secondary reactions induced by alpha (α) particles produced in the primary reactions. Use of a second nanosecond laser beam, adequately synchronized with the short laser pulse to produce a plasma target, further enhanced the reaction rates. High rates and chains of reactions are essential for most applications. PMID:26882988

  20. Laser-initiated primary and secondary nuclear reactions in Boron-Nitride

    NASA Astrophysics Data System (ADS)

    Labaune, C.; Baccou, C.; Yahia, V.; Neuville, C.; Rafelski, J.

    2016-02-01

    Nuclear reactions initiated by laser-accelerated particle beams are a promising new approach to many applications, from medical radioisotopes to aneutronic energy production. We present results demonstrating the occurrence of secondary nuclear reactions, initiated by the primary nuclear reaction products, using multicomponent targets composed of either natural boron (B) or natural boron nitride (BN). The primary proton-boron reaction (p + 11B → 3 α + 8.7 MeV), is one of the most attractive aneutronic fusion reaction. We report radioactive decay signatures in targets irradiated at the Elfie laser facility by laser-accelerated particle beams which we interpret as due to secondary reactions induced by alpha (α) particles produced in the primary reactions. Use of a second nanosecond laser beam, adequately synchronized with the short laser pulse to produce a plasma target, further enhanced the reaction rates. High rates and chains of reactions are essential for most applications.

  1. The US nuclear reaction data network. Summary of the first meeting, March 13 & 14 1996

    SciTech Connect

    1996-03-01

    The first meeting of the US Nuclear Reaction Data Network (USNRDN) was held at the Colorado School of Mines, March 13-14, 1996 chaired by F. Edward Cecil. The Agenda of the meeting is attached. The Network, its mission, products and services; related nuclear data and data networks, members, and organization are described in Attachment 1. The following progress reports from the members of the USNRDN were distributed prior to the meeting and are given as Attachment 2. (1) Measurements and Development of Analytic Techniques for Basic Nuclear Physics and Nuclear Applications; (2) Nuclear Reaction Data Activities at the National Nuclear Data Center; (3) Studies of nuclear reactions at very low energies; (4) Nuclear Reaction Data Activities, Nuclear Data Group; (5) Progress in Neutron Physics at Los Alamos - Experiments; (6) Nuclear Reaction Data Activities in Group T2; (7) Progress Report for the US Nuclear Reaction Data Network Meeting; (8) Nuclear Astrophysics Research Group (ORNL); (9) Progress Report from Ohio University; (10) Exciton Model Phenomenology; and (11) Progress Report for Coordination Meeting USNRDN.

  2. Studies in Low-Energy Nuclear Science

    SciTech Connect

    Carl R. Brune; Steven M. Grimes

    2010-01-13

    This report presents a summary of research projects in the area of low energy nuclear reactions and structure, carried out between March 1, 2006 and October 31, 2009 which were supported by U.S. DOE grant number DE-FG52-06NA26187.

  3. Nuclear Data Needs for Generation IV Nuclear Energy Systems

    NASA Astrophysics Data System (ADS)

    Rullhusen, Peter

    2006-04-01

    Nuclear data needs for generation IV systems. Future of nuclear energy and the role of nuclear data / P. Finck. Nuclear data needs for generation IV nuclear energy systems-summary of U.S. workshop / T. A. Taiwo, H. S. Khalil. Nuclear data needs for the assessment of gen. IV systems / G. Rimpault. Nuclear data needs for generation IV-lessons from benchmarks / S. C. van der Marck, A. Hogenbirk, M. C. Duijvestijn. Core design issues of the supercritical water fast reactor / M. Mori ... [et al.]. GFR core neutronics studies at CEA / J. C. Bosq ... [et al]. Comparative study on different phonon frequency spectra of graphite in GCR / Young-Sik Cho ... [et al.]. Innovative fuel types for minor actinides transmutation / D. Haas, A. Fernandez, J. Somers. The importance of nuclear data in modeling and designing generation IV fast reactors / K. D. Weaver. The GIF and Mexico-"everything is possible" / C. Arrenondo Sánchez -- Benmarks, sensitivity calculations, uncertainties. Sensitivity of advanced reactor and fuel cycle performance parameters to nuclear data uncertainties / G. Aliberti ... [et al.]. Sensitivity and uncertainty study for thermal molten salt reactors / A. Biduad ... [et al.]. Integral reactor physics benchmarks- The International Criticality Safety Benchmark Evaluation Project (ICSBEP) and the International Reactor Physics Experiment Evaluation Project (IRPHEP) / J. B. Briggs, D. W. Nigg, E. Sartori. Computer model of an error propagation through micro-campaign of fast neutron gas cooled nuclear reactor / E. Ivanov. Combining differential and integral experiments on [symbol] for reducing uncertainties in nuclear data applications / T. Kawano ... [et al.]. Sensitivity of activation cross sections of the Hafnium, Tanatalum and Tungsten stable isotopes to nuclear reaction mechanisms / V. Avrigeanu ... [et al.]. Generating covariance data with nuclear models / A. J. Koning. Sensitivity of Candu-SCWR reactors physics calculations to nuclear data files / K. S

  4. NUCLEAR ASTROPHYSICS PROJECT WITH A NEW LOW-ENERGY RIB SEPARATOR CRIB:. Study of a Critical Stellar Reaction 15O(α,γ)19Ne

    NASA Astrophysics Data System (ADS)

    Kubono, S.; Michimasa, S.; Teranishi, T.; Yanagisawa, Y.; Fulop, Z.; Liu, X.; Kumagai, K.; Abe, K.; Yun, C. C.; Watanabe, S.; Yamazaki, N.; Ohshiro, Y.; Kurokawa, M.; Strasser, P.; Hahn, K. I.; Kishida, T.; Imai, N.; Kato, S.; Fuchi, Y.; Tanaka, M. H.

    2003-04-01

    One of the critical stellar reactions for the onset of explosive hydrogen burning, 15O(α,γ)19Ne, is discussed with our recent experimental effort and a new possibility in our new RIB project. This reaction was investigated experimentally by indirect methods. Single particle nature of the threshold states was studied by the analog reactions, (d,t) and (d,3He) on 20Ne. The α-branching ratios for some states were also measured by a coincidence measurement of a triton and α from 19F(3He,t)19Ne*(α)15O(g.s.). Experimental plan for the problem was also discussed that uses a new low-energy RIB facility at CNS, called CRIB, which will come into operation soon.

  5. Study of Exotic Nuclear Structures via Total Reaction Cross Sections

    NASA Astrophysics Data System (ADS)

    Takechi, Maya

    2009-10-01

    Nuclear radius is one of the most basic physical quantities to study unknown exotic nuclei. A number of radii for unstable nuclei were studied through measurements of interaction cross sections (σI) at high energies, using the Glauber-type calculation (Optical-Limit approximation (OLA) of Glauber theory) to investigate halo and skin structures of exotic nuclei. On the other hand, it was indicated that reaction cross sections (σR) at intermediate energies (from several tens to hundreds of MeV/nucleon) were more sensitive to dilute nucleon density distribution owing to large nucleon-nucleon total cross sections (σNN) compared to high-energy region. Recently, we developed a new method to deduce nucleon density distributions from the energy dependences of σ R, through the precise measurements of σ R for various nuclei and some modifications of Glauber-type calculation. Using this method, we studied nucleon density distributions of light nuclei by measuring σ R for those nuclei at HIMAC (Heavy ion Medical Accelerator in CHIBA), NIRS (National Institute of Radiological Sciences). And very recently, we deduced nuclear radii of neutron-rich Ne isotopes (^28-32Ne) which are in the island-of-inversion region by measuring σI using BigRIPS at RIBF (RI Beam Factory) to study nuclear structures of those isotopes using our method. In this workshop, results of nucleon density distributions obtained at HIMAC and results of the studies of Ne isotopes at RIBF will be introduced and discussed.

  6. Identifying Understudied Nuclear Reactions by Text-mining the EXFOR Experimental Nuclear Reaction Library

    NASA Astrophysics Data System (ADS)

    Hirdt, J. A.; Brown, D. A.

    2016-01-01

    The EXFOR library contains the largest collection of experimental nuclear reaction data available as well as the data's bibliographic information and experimental details. We text-mined the REACTION and MONITOR fields of the ENTRYs in the EXFOR library in order to identify understudied reactions and quantities. Using the results of the text-mining, we created an undirected graph from the EXFOR datasets with each graph node representing a single reaction and quantity and graph links representing the various types of connections between these reactions and quantities. This graph is an abstract representation of the connections in EXFOR, similar to graphs of social networks, authorship networks, etc. We use various graph theoretical tools to identify important yet understudied reactions and quantities in EXFOR. Although we identified a few cross sections relevant for shielding applications and isotope production, mostly we identified charged particle fluence monitor cross sections. As a side effect of this work, we learn that our abstract graph is typical of other real-world graphs.

  7. 76 FR 78252 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-16

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Department of Energy, Office of Nuclear Energy. ACTION: Notice of... Management Secretariat, General Services Administration, notice is hereby given that the Nuclear...

  8. Vision of nuclear physics with photo-nuclear reactions by laser-driven γ beams

    NASA Astrophysics Data System (ADS)

    Habs, D.; Tajima, T.; Schreiber, J.; Barty, C. P. J.; Fujiwara, M.; Thirolf, P. G.

    2009-11-01

    A laser-accelerated dense electron sheet with an energy E=tilde{γ} mc^2 can be used as a relativistic mirror to coherently reflect a second laser with photon energy ħω, thus generating by the Doppler boost [A. Einstein, Annalen der Physik 17, 891 (1905); D. Habs et al., Appl. Phys. B 93, 349 (2008)] brilliant high-energy photon beams with hbarω^'=4tilde{γ}^2hbarω and short duration for many new nuclear physics experiments. While the shortest-lived atomic levels are in the atto-second range, nuclear levels can have lifetimes down to zeptoseconds. We discuss how the modulation of electron energies in phase-locked laser fields used for as-measurements [E. Goulielmakis et al., Science 317, 769 (2007)] can be carried over to the new direct measurement of fs-zs nuclear lifetimes by modulating the energies of accompanying conversion electrons or emitted protons. In the field of nuclear spectroscopy we discuss the new perspective as a function of increasing photon energy. In nuclear systems a much higher sensitivity is predicted to the time variation of fundamental constants compared to atomic systems [V. Flambaum, arXiv:nucl-th/0801.1994v1 (2008)]. For energies up to 50 keV Mössbauer-like recoilless absorption allows to produce nuclear bosonic ensembles with many delocalized coherent polaritons [G.V. Smirnov et al., Phys. Rev. A 71, 023804 (2005)] for the first time. Using the ( γ, n) reaction to produce cold, polarized neutrons with a focusing ellipsoidal device [P. Böni, Nucl. Instrum. Meth. A 586, 1 (2008); Ch. Schanzer et al., Nucl. Instrum. Meth. 529, 63 (2004)], brilliant cold polarized micro-neutron beams become available. The compact and relatively cheap laser-generated γ beams may serve for extended studies at university-based facilities.

  9. Data requirements for intermediate energy nuclear applications

    SciTech Connect

    Pearlstein, S.

    1990-01-01

    Several applications that include spallation neutron sources, space radiation effects, biomedical isotope production, accelerator shielding and radiation therapy make use of intermediate energy nuclear data extending to several GeV. The overlapping data needs of these applications are discussed in terms of what projectiles, targets and reactions are of interest. Included is a discussion of what is generally known about these data and what is needed to facilitate their use in intermediate energy applications. 40 refs., 2 figs., 2 tabs.

  10. NESST: A nuclear energy safety and security treaty-Separating nuclear energy from nuclear weapons

    NASA Astrophysics Data System (ADS)

    McNamara, Brendan

    2012-06-01

    Fission and Fusion energy is matched by the need to completely separate civilian energy programmes from the production of nuclear weapons. The Nuclear Proliferation Treaty (NPT, 1968) muddles these issues together. The case is presented here for making a new Nuclear Energy Security Treaty (NESST) which is rigorous, enforceable without violence, and separate from the political quagmire of nuclear weapons.

  11. Social Institutions and Nuclear Energy

    ERIC Educational Resources Information Center

    Weinberg, Alvin M.

    1972-01-01

    Nuclear technologists can offer an all but infinite source of relatively cheap and clean energy" but society must decide whether the price of eternal vigilance needed to ensure proper and safe operation of its nuclear energy system" is worth the benefits. (Author/AL)

  12. Nuclear energy: basics, present, future

    NASA Astrophysics Data System (ADS)

    Ricotti, M. E.

    2013-06-01

    The contribution is conceived for non-nuclear experts, intended as a synthetic and simplified overview of the technology related to energy by nuclear fission. At the end of the paper, the Reader will find a minimal set of references, several of them on internet, useful to start deepening the knowledge on this challenging, complex, debated albeit engaging energy source.

  13. Nuclear and gravitational energies in stars

    SciTech Connect

    Meynet, Georges; Ekström, Sylvia; Courvoisier, Thierry

    2014-05-09

    The force that governs the evolution of stars is gravity. Indeed this force drives star formation, imposes thermal and density gradients into stars at hydrostatic equilibrium and finally plays the key role in the last phases of their evolution. Nuclear power in stars governs their lifetimes and of course the stellar nucleosynthesis. The nuclear reactions are at the heart of the changes of composition of the baryonic matter in the Universe. This change of composition, in its turn, has profound consequences on the evolution of stars and galaxies. The energy extracted from the gravitational, respectively nuclear reservoirs during the lifetimes of stars of different masses are estimated. It is shown that low and intermediate mass stars (M < 8 M{sub ⊙}) extract roughly 90 times more energy from their nuclear reservoir than from their gravitational one, while massive stars (M > 8 M{sub ⊙}), which explode in a supernova explosion, extract more than 5 times more energy from the gravitational reservoir than from the nuclear one. We conclude by discussing a few important nuclear reactions and their link to topical astrophysical questions.

  14. Nuclear waste vitrification efficiency: cold cap reactions

    SciTech Connect

    Hrma, Pavel R.; Kruger, Albert A.; Pokorny, Richard

    2012-12-15

    The cost and schedule of nuclear waste treatment and immobilization are greatly affected by the rate of glass production. Various factors influence the performance of a waste-glass melter. One of the most significant, and also one of the least understood, is the process of batch melting. Studies are being conducted to gain fundamental understanding of the batch reactions, particularly those that influence the rate of melting, and models are being developed to link batch makeup and melter operation to the melting rate. Batch melting takes place within the cold cap, i.e., a batch layer floating on the surface of molten glass. The conversion of batch to glass consists of various chemical reactions, phase transitions, and diffusion-controlled processes. These include water evaporation (slurry feed contains as high as 60% water), gas evolution, the melting of salts, the formation of borate melt, reactions of borate melt with molten salts and with amorphous oxides (Fe2O3 and Al2O3), the formation of intermediate crystalline phases, the formation of a continuous glass-forming melt, the growth and collapse of primary foam, and the dissolution of residual solids. To this list we also need to add the formation of secondary foam that originates from molten glass but accumulates on the bottom of the cold cap. This study presents relevant data obtained for a high-level-waste melter feed and introduces a one-dimensional (1D) mathematical model of the cold cap as a step toward an advanced three-dimensional (3D) version for a complete model of the waste glass melter. The 1D model describes the batch-to-glass conversion within the cold cap as it progresses in a vertical direction. With constitutive equations and key parameters based on measured data, and simplified boundary conditions on the cold-cap interfaces with the glass melt and the plenum space of the melter, the model provides sensitivity analysis of the response of the cold cap to the batch makeup and melter conditions

  15. NUCLEAR WASTE VITRIFICATION EFFICIENCY COLD CAP REACTIONS

    SciTech Connect

    KRUGER AA; HRMA PR; POKORNY R

    2011-07-29

    The cost and schedule of nuclear waste treatment and immobilization are greatly affected by the rate of glass production. Various factors influence the performance of a waste-glass melter. One of the most significant, and also one of the least understood, is the process of batch melting. Studies are being conducted to gain fundamental understanding of the batch reactions, particularly those that influence the rate of melting, and models are being developed to link batch makeup and melter operation to the melting rate. Batch melting takes place within the cold cap, i.e., a batch layer floating on the surface of molten glass. The conversion of batch to glass consists of various chemical reactions, phase transitions, and diffusion-controlled processes. These include water evaporation (slurry feed contains as high as 60% water), gas evolution, the melting of salts, the formation of borate melt, reactions of borate melt with molten salts and with amorphous oxides (Fe{sub 2}O{sub 3} and Al{sub 2}O{sub 3}), the formation of intermediate crystalline phases, the formation of a continuous glass-forming melt, the growth and collapse of primary foam, and the dissolution of residual solids. To this list we also need to add the formation of secondary foam that originates from molten glass but accumulates on the bottom of the cold cap. This study presents relevant data obtained for a high-level-waste melter feed and introduces a one-dimensional (1D) mathematical model of the cold cap as a step toward an advanced three-dimensional (3D) version for a complete model of the waste glass melter. The 1D model describes the batch-to-glass conversion within the cold cap as it progresses in a vertical direction. With constitutive equations and key parameters based on measured data, and simplified boundary conditions on the cold-cap interfaces with the glass melt and the plenum space of the melter, the model provides sensitivity analysis of the response of the cold cap to the batch makeup

  16. Deexcitation Modes in Spallation Nuclear Reactions

    NASA Astrophysics Data System (ADS)

    Velasco, F. G.; Guzmán, F.; Rodriguez, O.; Tumbarell, O.; Souza, D. A.; Samana, A. R.; Andrade-II, E.; Bernal Castillo, J. L.; Deppman, A.

    2016-08-01

    Spallation nuclear reactions in the range of 0.2 to 1.2 GeV are studied using the CRISP code. A new approach for the deexcitation stage of the compound nucleus was introduced. For the calculations of the level densities, this approach is based on the Back-shifted Fermi gas model (BSFG), which takes into account pairing effects and shell corrections, whereas the calculation of the fission barriers were performed by means of the Extended Thomas-Fermi plus Strutinsky Integral (ETFSI) method, which is a high-speed approximation to the Hartree-Fock method with pairing correlations treated as in the usual BCS plus blocking approach. This procedure is more appropriate to calculate level densities for exotic nuclei. Satisfactory results were obtained and compared with experimental data obtained in the GSI experiments. As another important result, we highlight some directions for the development of a qualitatively superior version of the CRISP code with the implementation of more realistic and suitable physical models to be applied in stable and exotic nuclei that participate in the process. This new version of the code includes several substantial changes in the decay of the hot compound nucleus which allow satisfactory agreement with the experimental data and a reduction of the adjustment parameters.

  17. Ab Initio Calculations Of Nuclear Reactions And Exotic Nuclei

    SciTech Connect

    Quaglioni, S.

    2014-05-05

    Our ultimate goal is to develop a fundamental theory and efficient computational tools to describe dynamic processes between nuclei and to use such tools toward supporting several DOE milestones by: 1) performing predictive calculations of difficult-to-measure landmark reactions for nuclear astrophysics, such as those driving the neutrino signature of our sun; 2) improving our understanding of the structure of nuclei near the neutron drip line, which will be the focus of the DOE’s Facility for Rare Isotope Beams (FRIB) being constructed at Michigan State University; but also 3) helping to reveal the true nature of the nuclear force. Furthermore, these theoretical developments will support plasma diagnostic efforts at facilities dedicated to the development of terrestrial fusion energy.

  18. EMPIRE: Nuclear Reaction Model Code System for Data Evaluation

    NASA Astrophysics Data System (ADS)

    Herman, M.; Capote, R.; Carlson, B. V.; Obložinský, P.; Sin, M.; Trkov, A.; Wienke, H.; Zerkin, V.

    2007-12-01

    EMPIRE is a modular system of nuclear reaction codes, comprising various nuclear models, and designed for calculations over a broad range of energies and incident particles. A projectile can be a neutron, proton, any ion (including heavy-ions) or a photon. The energy range extends from the beginning of the unresolved resonance region for neutron-induced reactions (∽ keV) and goes up to several hundred MeV for heavy-ion induced reactions. The code accounts for the major nuclear reaction mechanisms, including direct, pre-equilibrium and compound nucleus ones. Direct reactions are described by a generalized optical model (ECIS03) or by the simplified coupled-channels approach (CCFUS). The pre-equilibrium mechanism can be treated by a deformation dependent multi-step direct (ORION + TRISTAN) model, by a NVWY multi-step compound one or by either a pre-equilibrium exciton model with cluster emission (PCROSS) or by another with full angular momentum coupling (DEGAS). Finally, the compound nucleus decay is described by the full featured Hauser-Feshbach model with γ-cascade and width-fluctuations. Advanced treatment of the fission channel takes into account transmission through a multiple-humped fission barrier with absorption in the wells. The fission probability is derived in the WKB approximation within the optical model of fission. Several options for nuclear level densities include the EMPIRE-specific approach, which accounts for the effects of the dynamic deformation of a fast rotating nucleus, the classical Gilbert-Cameron approach and pre-calculated tables obtained with a microscopic model based on HFB single-particle level schemes with collective enhancement. A comprehensive library of input parameters covers nuclear masses, optical model parameters, ground state deformations, discrete levels and decay schemes, level densities, fission barriers, moments of inertia and γ-ray strength functions. The results can be converted into ENDF-6 formatted files using the

  19. An Assessment of Nuclear Isomers as an Energy Storage Medium

    SciTech Connect

    Hartouni, E P

    2008-12-08

    Nuclear Isomers have been suggested as a potential high energy density medium that might be used to store energy. This talk assesses the state of the science supporting key elements of using nuclear isomers in energy storage applications. The focus is on the nuclear isomer {sup 178m2}Hf which has been most widely suggested for energy storage applications. However, the science issues apply to all nuclear isomer. The assessment addresses the production of the nuclear isomer, and inducing the release of the isomer. Also discussed are novel speculations on photon and/or neutron chain reactions, both as a 'pure' material as well as mixed with other materials.

  20. An Assessment of Nuclear Isomers as an Energy Storage Medium

    SciTech Connect

    Hartouni, Edward P.

    2009-03-16

    Nuclear Isomers have been suggested as a potential high energy density medium that might be used to store energy. This talk assesses the state of the science supporting key elements of using nuclear isomers in energy storage applications. The focus is on the nuclear isomer {sup 178m2}Hf which has been most widely suggested for energy storage applications. However, the science issues apply to all nuclear isomer. The assessment addresses the production of the nuclear isomer, and inducing the release of the isomer. Also discussed are novel speculations on photon and/or neutron chain reactions, both as a 'pure' material as well as mixed with other materials.

  1. Study of astrophysical ({alpha}, n) reactions using light-neutron rich radioactive nuclear beams

    SciTech Connect

    Ishiyama, Hironobu; Watanabe, Yutaka; Imai, Nobuaki; Hirayama, Yoshikazu; Miyatake, Hiroari; Tanaka, Masa-Hiko; Yoshikawa, Nobuharu; Jeong, Sunchan; Fuchi, Yoshihide; Katayama, Ichiro; Nomura, Toru; Ishikawa, Tomoko; Das, Suranjan K.; Mizoi, Yutaka; Fukuda, Tomokazu; Hashimoto, Takashi; Nishio, Katsuhisa; Mitsuoka, Shinichi; Ikezoe, Hiroshi; Matsuda, Makoto

    2006-07-12

    A systematic study of astrophysical reaction rates of ({alpha}, n) reactions on light neutron-rich nuclei using low-energy radioactive nuclear beams is in progress at the tandem facility of Japan Atomic Energy Agency. Exclusive measurements of 8Li({alpha}, n)11B and 12B({alpha}, n)15N reaction cross sections have been performed successfully. Their excitation functions together with the experimental method are presented.

  2. Indirect measurements of nuclear astrophysics reactions at CIAE

    SciTech Connect

    Liu Weiping; Li Zhihong; Bai Xixiang; Wang Youbao; Lian Gang; Guo Bing; Zeng Sheng; Yan Shengquan; Wang Baoxiang; Su Jun; Shu Nengchuan; Chen Yongshou

    2006-11-02

    This paper described the nuclear astrophysical studies using the unstable ion beam facility GIRAFFE, by indirect measurements. We measured the angular distributions for some single proton or neutron transfer reactions, such as 7Be(d,n)8B, 11C(d,n)12N, 8Li(d,n)9Be, 8Li(d,p)9Li and 13N(d,n)14O in inverse kinematics, and derived the astrophysical S-factors or reaction rates of 7Be(p,{gamma})8B, 11C(p,{gamma})12N, 8Li(n,{gamma})9Li, 13N(p,{gamma})14O by asymptotic normalization coefficient, spectroscopic factor, and R-matrix approach at astrophysically relevant energies.

  3. Solar He-3: Information from nuclear reactions in flares

    NASA Technical Reports Server (NTRS)

    Ramaty, R.; Kozlovsky, B.

    1974-01-01

    Information on solar He-3 from nuclear reactions in flares was considered. Consideration was also given to the development of models for these reactions as well as the abundance of He-3 in the photosphere. Data show that abundances may be explained by nuclear reactions of flare acceleration protons and alpha particles with the ambient atmosphere, provided that various assumptions are made on the directionality of the interacting beams and acceleration of the particles after production.

  4. High energy nuclear structures

    SciTech Connect

    Boguta, J.; Kunz, J.

    1984-03-09

    In conventional nuclear physics the nucleus is described as a non-relativistic many-body system, which is governed by the Schroedinger equation. Nucleons interact in this framework via static two-body potentials, mesonic degrees of freedom are neglected. An alternative description of nuclear physics in terms of a relativistic field theory has been developed by Walecka. The model Lagrangian containing baryons, sigma-mesons and ..omega..-mesons was subsequently extended to include also ..pi..-mesons and rho-mesons. An essential feature of such a nuclear Lagrangian is its renormalizability. In addition to the description of known nuclear structure the field theoretical approach may reveal entirely new nuclear phenomena, based on the explicit treatment of mesonic degrees of freedom. The existence of such abnormal nuclear states was proposed by Lee and Wick employing the sigma-model Lagrangian. There the non-linearity of the meson field equations allows for soliton solutions in the presence of nucleons, in particular the sigma-field may exhibit a kink. Different types of soliton solutions occur in gauge theories with hidden symmetries. In the phenomenological Lagrangian the rho-meson is described by a non-abelian gauge field, that acquires its mass spontaneously due to the non-vanishing vacuum expectation value of a Higgs field. A general ansatz for soliton solutions of such a gauge theory was given by Dashen et al. A specific solution and its possible implications for nuclear physics like anomalous nuclear states were discussed by Boguta.

  5. Nuclear Structure of 97Mo from the (d, p) Reaction

    NASA Astrophysics Data System (ADS)

    Chowdhury, M. S.; Booth, W.

    The reaction 96Mo(d, p)97Mo has been studied at 12 MeV using the tandem Van de Graaff accelerator and a multi-channel magnetic spectrograph at the Atomic Weapon Research Establishment, Aldermaston, England. Angular distributions of protons are measured at 12 different angles from 5° to 87.5° at an interval of 7.5° and the reaction products are detected in nuclear emulsion plates. Thirty levels in the energy range from 0.000 to 2.458 MeV have been observed and absolute differential cross-sections for these levels have been measured. The data are analyzed in terms of the distorted-wave Born approximation (DWBA) theory of the direct reactions, and spins, parities and spectroscopic factors are deduced for various levels. Ambiguity in the spin assignments of d5/2 and d3/2 which is allowed in ln = 2(d, p) transition is removed by using the corresponding L-value of the 95 Mo(t, p)97Mo reaction at Et = 12 MeV. Determined value of the sum of spectroscopic factors for transfers of d5/2 neutrons suggests configuration mixing in the ground state of 96Mo. The properties of the levels in 97Mo are compared with previous experimental results and theoretical predictions.

  6. Maruhn-Greiner Maximum of Uranium Fission for Confirmation of Low Energy Nuclear Reactions LENR via a Compound Nucleus with Double Magic Numbers

    NASA Astrophysics Data System (ADS)

    Hora, H.; Miley, G. H.

    2007-12-01

    One of the most convincing facts about LENR due to deuterons of very high concentration in host metals as palladium is the measurement of the large scale minimum of the reaction probability depending on the nucleon number A of generated elements at A = 153 where a local maximum was measured. This is similar to the fission of uranium at A = 119 where the local maximum follows from the Maruhn-Greiner theory if the splitting nuclei are excited to about MeV energy. The LENR generated elements can be documented any time after the reaction by SIMS or K-shell X-ray excitation to show the very unique distribution with the local maximum. An explanation is based on the strong Debye screening of the Maxwellian deuterons within the degenerate rigid electron background especially within the swimming electron layer at the metal surface or at interfaces. The deuterons behave like neutrals at distances of about 2 picometers. They may form clusters due to soft attraction in the range above thermal energy. Clusters of 10 pm diameter may react over long time probabilities (megaseconds) with Pd nuclei leading to a double magic number compound nucleus which splits like in fission to the A = 153 element distribution.

  7. Dynamic Analysis of Nuclear Energy System Strategies

    SciTech Connect

    Den Durpel, Luc Van

    2004-06-17

    DANESS is an integrated process model for nuclear energy systems allowing the simulation of multiple reactors and fuel cycles in a continuously changing nuclear reactor park configuration. The model is energy demand driven and simulates all nuclear fuel cycle facilites, up to 10 reactors and fuels. Reactor and fuel cycle facility history are traced and the cost of generating energy is calculated per reactor and for total nuclear energy system. The DANESS model aims at performing dynamic systems analysis of nuclear energy development used for integrated analysis of development paths for nuclear energy, parameter scoping for new nuclear energy systems, economic analysis of nuclear energy, government role analysis, and education.

  8. Secondary Nuclear Reactions in Magneto-Inertial Fusion Plasmas

    NASA Astrophysics Data System (ADS)

    Knapp, Patrick

    2014-10-01

    The goal of Magneto-Inertial Fusion (MIF) is to relax the extreme pressure requirements of inertial confinement fusion by magnetizing the fuel. Understanding the level of magnetization at stagnation is critical for charting the performance of any MIF concept. We show here that the secondary nuclear reactions in magnetized deuterium plasma can be used to infer the magnetic field-radius product (BR), the critical confinement parameter for MIF. The secondary neutron yields and spectra are examined and shown to be extremely sensitive to BR. In particular, embedded magnetic fields are shown to affect profoundly the isotropy of the secondary neutron spectra. Detailed modeling of these spectra along with the ratio of overall secondary to primary neutron yields is used to form the basis of a diagnostic technique used to infer BR at stagnation. Effects of gradients in density, temperature and magnetic field strength are examined, as well as other possible non-uniform fuel configurations. Computational results employing a fully kinetic treatment of charged reaction product transport and Monte Carlo treatment of secondary reactions are compared to results from recent experiments at Sandia National Laboratories' Z machine testing the MAGnetized Liner Inertial Fusion (MagLIF) concept. The technique reveals that the charged reaction products were highly magnetized in these experiments. Implications for eventual ignition-relevant experiments with deuterium-tritium fuel are discussed. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  9. Building a Universal Nuclear Energy Density Functional

    SciTech Connect

    Carlson, Joe A.; Furnstahl, Dick; Horoi, Mihai; Lust, Rusty; Nazaewicc, Witek; Ng, Esmond; Thompson, Ian; Vary, James

    2012-12-30

    During the period of Dec. 1 2006 – Jun. 30, 2012, the UNEDF collaboration carried out a comprehensive study of all nuclei, based on the most accurate knowledge of the strong nuclear interaction, the most reliable theoretical approaches, the most advanced algorithms, and extensive computational resources, with a view towards scaling to the petaflop platforms and beyond. The long-term vision initiated with UNEDF is to arrive at a comprehensive, quantitative, and unified description of nuclei and their reactions, grounded in the fundamental interactions between the constituent nucleons. We seek to replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that delivers maximum predictive power with well-quantified uncertainties. Specifically, the mission of this project has been three-fold:  First, to find an optimal energy density functional (EDF) using all our knowledge of the nucleonic Hamiltonian and basic nuclear properties;  Second, to apply the EDF theory and its extensions to validate the functional using all the available relevant nuclear structure and reaction data;  Third, to apply the validated theory to properties of interest that cannot be measured, in particular the properties needed for reaction theory.

  10. Nuclear reactions and synthesis of new transuranium species

    SciTech Connect

    Seaborg, G.T.

    1983-01-01

    In this short review, I shall describe the special aspects of heavy ion nuclear reaction mechanisms operative in the transuranium region, the role of new techniques, possible nuclear reactions for the production of additional transuranium elements and nuclear species and the importance of work in this region for the development of nuclear models and theoretical concepts. This discussion should make it clear that a continuing supply of leements and isotopes, some fo them relatively short-lived, produced by the HFIR-TRU facilities, will be a requirement for future synthesis of new elements and isotopes.

  11. Nuclear reaction modeling, verification experiments, and applications

    SciTech Connect

    Dietrich, F.S.

    1995-10-01

    This presentation summarized the recent accomplishments and future promise of the neutron nuclear physics program at the Manuel Lujan Jr. Neutron Scatter Center (MLNSC) and the Weapons Neutron Research (WNR) facility. The unique capabilities of the spallation sources enable a broad range of experiments in weapons-related physics, basic science, nuclear technology, industrial applications, and medical physics.

  12. The CCONE Code System and its Application to Nuclear Data Evaluation for Fission and Other Reactions

    NASA Astrophysics Data System (ADS)

    Iwamoto, O.; Iwamoto, N.; Kunieda, S.; Minato, F.; Shibata, K.

    2016-01-01

    A computer code system, CCONE, was developed for nuclear data evaluation within the JENDL project. The CCONE code system integrates various nuclear reaction models needed to describe nucleon, light charged nuclei up to alpha-particle and photon induced reactions. The code is written in the C++ programming language using an object-oriented technology. At first, it was applied to neutron-induced reaction data on actinides, which were compiled into JENDL Actinide File 2008 and JENDL-4.0. It has been extensively used in various nuclear data evaluations for both actinide and non-actinide nuclei. The CCONE code has been upgraded to nuclear data evaluation at higher incident energies for neutron-, proton-, and photon-induced reactions. It was also used for estimating β-delayed neutron emission. This paper describes the CCONE code system indicating the concept and design of coding and inputs. Details of the formulation for modelings of the direct, pre-equilibrium and compound reactions are presented. Applications to the nuclear data evaluations such as neutron-induced reactions on actinides and medium-heavy nuclei, high-energy nucleon-induced reactions, photonuclear reaction and β-delayed neutron emission are mentioned.

  13. Theoretical studies in nuclear reactions and nuclear structure

    SciTech Connect

    Not Available

    1992-05-01

    Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon's mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon's mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e{sup +}e{sup {minus}} problem and heavy ion dynamics.

  14. Theoretical studies in nuclear reactions and nuclear structure. Progress report

    SciTech Connect

    Not Available

    1992-05-01

    Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon`s mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon`s mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon`s mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e{sup +}e{sup {minus}} problem and heavy ion dynamics.

  15. Microscopic effective reaction theory for direct nuclear reactions

    NASA Astrophysics Data System (ADS)

    Ogata, Kazuyuki; Minomo, Kosho; Toyokawa, Masakazu; Kohno, Michio; Matsumoto, Takuma; Yahiro, Masanobu; Kikuchi, Yuma; Fukui, Tokuro; Yoshida, Kazuki; Mizuyama, Kazuhito

    2016-06-01

    Some recent activities with the microscopic effective reaction theory (MERT) on elastic, inelastic, breakup, transfer, and knockout processes are reviewed briefly. As a possible alternative to MERT, a description of elastic and inelastic scattering with the continuum particle-vibration coupling (cPVC) method is also discussed.

  16. Electromagnetic studies of nuclear structure and reactions

    SciTech Connect

    Hersman, F.W.; Dawson, J.F.; Heisenberg, J.H.; Calarco, J.R.

    1990-06-01

    This report contains papers on the following topics: giant resonance studies; deep inelastic scattering studies; high resolution nuclear structure work; and relativistic RPA; and field theory in the Schroedinger Representation.

  17. Ab initio calculations of nuclear reactions important for astrophysics

    NASA Astrophysics Data System (ADS)

    Navratil, Petr; Dohet-Eraly, Jeremy; Calci, Angelo; Horiuchi, Wataru; Hupin, Guillaume; Quaglioni, Sofia

    2016-09-01

    In recent years, significant progress has been made in ab initio nuclear structure and reaction calculations based on input from QCD employing Hamiltonians constructed within chiral effective field theory. One of the newly developed approaches is the No-Core Shell Model with Continuum (NCSMC), capable of describing both bound and scattering states in light nuclei simultaneously. We will present NCSMC results for reactions important for astrophysics that are difficult to measure at relevant low energies, such as 3He(α,γ)7Be and 3H(α,γ)7Li and 11C(p,γ)12N radiative capture, as well as the 3H(d,n)4He fusion. We will also address prospects of calculating the 2H(α,γ)6Li capture reaction within the NCSMC formalism. Prepared in part by LLNL under Contract DE-AC52-07NA27344. Supported by the U.S. DOE, OS, NP, under Work Proposal No. SCW1158, and by the NSERC Grant No. SAPIN-2016-00033. TRIUMF receives funding from the NRC Canada.

  18. Direct Reactions for Nuclear Structure and Nuclear Astrophysics

    SciTech Connect

    Jones, Katherine Louise

    2014-12-18

    Direct reactions are powerful probes for studying the atomic nucleus. Modern direct reaction studies are illuminating both the fundamental nature of the nucleus and its role in nucleosynthetic processes occurring in the cosmos. This report covers experiments using knockout reactions on neutron-deficient fragmentation beams, transfer reactions on fission fragment beams, and theoretical sensitivity studies relating to the astrophysical r-process. Results from experiments on 108,106Sn at the NSCL, and on 131Sn at HRIBF are presented as well as the results from the nucleosynthesis study.

  19. Nuclear reactions in Rb, Sr, Y, and Zr targets

    NASA Astrophysics Data System (ADS)

    Regnier, S.; Lavielle, B.; Simonoff, M.; Simonoff, G. N.

    1982-09-01

    Excitation functions of all stable or long-lived krypton isotopes were measured or estimated for incident protons and neutrons in Rb, Sr, Y, and Zr targets. Experimental data concern mostly Y and Zr targets bombarded with 0.059 to 24 GeV protons. The products 78-86Kr, 74As, 75Se, 83,84,86Rb, 85Sr, 88Y, 88,95Zr, and 92Nbm were measured using high-sensitivity mass spectrometry and nondestructive γ counting. Lighter products such as 38,39,42Ar and 12 radioactive isotopes from 7Be to 65Zn were also measured in some cases and their cross sections are given in an appendix. Most excitation functions pass through a maximum between 0.4 and 0.8 GeV, and the peak energy could depend on the ΔA value. The results, combined with a general survey of nuclear reactions in Ga to Nb targets, permitted the development of new systematics leading to the calculation of spallation-produced Kr isotopes in the moon bombarded with galactic and solar cosmic rays. Compared to cosmogenic krypton measured in nine well-documented lunar samples, 83Kr is predicted with a precision better than 33% (1σ) and the production ratios iKr/83Kr are predicted to better than 25%. It is concluded that the cosmogenic ratios 86Kr/83Kr and 81Kr/83Kr are dependent on the main target element concentrations. This should be taken into account in strontium-rich samples when calculating exposure ages of extraterrestrial materials. NUCLEAR REACTIONS 89Y and Zr, (p, spallation) E=0.059-24 GeV; measured σ(E) for 78-86Kr and 12 radioactive products. Systematics of p- and n-induced reactions in Rb, Sr, Y, and Zr. Cosmogenic krypton.

  20. Nuclear Reaction and Structure Databases of the National Nuclear Data Center

    SciTech Connect

    Pritychenko, B.; Arcilla, R.; Herman, M. W.; Oblozinsky, P.; Rochman, D.; Sonzogni, A. A.; Tuli, J. K.; Winchell, D. F.

    2006-03-13

    The National Nuclear Data Center (NNDC) collects, evaluates, and disseminates nuclear physics data for basic research and applied nuclear technologies. In 2004, the NNDC migrated all databases into modern relational database software, installed new generation of Linux servers and developed new Java-based Web service. This nuclear database development means much faster, more flexible and more convenient service to all users in the United States. These nuclear reaction and structure database developments as well as related Web services are briefly described.

  1. Angular Dependency and Kinematics of Light Atom Nuclear Reactions with Positive Q Values

    NASA Astrophysics Data System (ADS)

    Pacheco, Jose; Naab, Fabian; Marble, Daniel; Duggan, Jerome

    2006-10-01

    Einstein's relationship, E=mĉ2 implies that energy can be changed into mass and vice versa. Using nuclear reaction analysis, the interchange of mass into energy can be used to analyze trace elements in a material since each given element has a set of nuclear reactions that are unique to it. These nuclear reactions have positive Q values, which show up as excess energy in the emitted particle spectrum. However accurate interpretation of these spectra for materials analysis can be complicated as knowledge of both the angular dependency of the reaction and the geometry of the detection setup is required. The angular dependence is usually easily taken into account provided the reaction is well known and there are no nuclear interferences. In this experiment, a 1 MeV proton beam from a 2.5 MeV Van De Graff was applied to targets made up of light atoms, mainly 7Li, 6Li, and 19F. The results demonstrate the importance of accurately knowing the detection configuration, geometry, and the effect of detection system resolution when doing NRA. For instance, our system failed to give any information about the nuclear reaction for angles less than 30 degrees from the incoming beam due to its resolution.

  2. Nuclear Energy Present and Future

    NASA Astrophysics Data System (ADS)

    Hutchinson, I. H.

    2006-10-01

    Nuclear power plants currently generate about 20% of US and 17% of world electricity, which makes nuclear the largest non-emitting energy source in current use. Concerns about global climate change have led to a remarkable transformation of attitudes towards nuclear energy. There remain key challenges that must be faced when considering expansion of its contribution. In summary they are: Economics, Safety, Waste Disposal, and Proliferation. Electricity from legacy fission plants is highly competitive with fossil, but perceived financial risks make the large capital cost fraction a key hurdle to new-construction, and costs of 2 per installed Watt electrical are currently considered only just economically attractive. Proliferation of nuclear-weapons-enabling technology is a major concern for global stability, in which fusion may have significant technical advantages over fission. But proliferation control requires a combination of both technical and political initiatives. The feasibility of supplying process heat or hydrogen from nuclear energy inspires additional research into novel reactor concepts and associated technologies. The presentation will lay out this overall context of the nuclear energy renaissance.

  3. ICENES '91:Sixth international conference on emerging nuclear energy systems

    SciTech Connect

    Not Available

    1991-01-01

    This document contains the program and abstracts of the sessions at the Sixth International Conference on Emerging Nuclear Energy Systems held June 16--21, 1991 at Monterey, California. These sessions included: The plenary session, fission session, fission and nonelectric session, poster session 1P; (space propulsion, space nuclear power, electrostatic confined fusion, fusion miscellaneous, inertial confinement fusion, [mu]-catalyzed fusion, and cold fusion); Advanced fusion session, space nuclear session, poster session 2P, (nuclear reactions/data, isotope separation, direct energy conversion and exotic concepts, fusion-fission hybrids, nuclear desalting, accelerator waste-transmutation, and fusion-based chemical recycling); energy policy session, poster session 3P (energy policy, magnetic fusion reactors, fission reactors, magnetically insulated inertial fusion, and nuclear explosives for power generation); exotic energy storage and conversion session; and exotic energy storage and conversion; review and closing session.

  4. Studies in Low-Energy Nuclear Science

    SciTech Connect

    Brune, Carl R; Grimes, Steven M

    2006-03-30

    This report presents a summary of research projects in the area of low energy nuclear reactions and structure, carried out between 1 January 2003 and 31 December 2005 and supported by U.S. DOE grant number DE-FG03-03NA00074. Cross sections measured with high resolution have been subjected to an Ericson theory analysis to infer information about the nuclear level density. Other measurements were made of the spectral shape of particles produced in evaporation processes; these also yield level density information. A major project was the development of a new Hauser-Feshbach code for analyzing such spectra. Other measurements produced information on the spectra of gamma rays emitted in reactions on heavy nuclei and gave a means of refining our understanding of gamma-ray strength functions. Finally,reactions on light nuclei were studied and subjected to an R-matrix analysis. Cross sections fora network of nuclear reactions proceedingthrough a given compound nucleus shouldgreatly constrain the family of allowed parameters. Modifications to the formalism andcomputer code are also discussed.

  5. In vitro splicing reactions in Drosophila Kc nuclear extracts.

    PubMed

    Rio, Donald C

    2014-08-01

    This protocol describes how to generate and analyze products and intermediates in a pre-mRNA splicing reaction. The reaction relies on the use of labeled, capped, synthetic pre-mRNAs, prepared by in vitro transcription, and Drosophila Kc cell culture nuclear extracts. The pre-mRNA substrate is incubated in the nuclear extract under splicing conditions for 1-2 h. The products of the reaction are purified by phenol:chloroform extraction and precipitation with ethanol, and then loaded directly onto a denaturing urea-acrylamide gel. Visualization of the splicing reactions will reveal the pre-mRNA, the spliced mRNA, and the intermediates generated by the first step of splicing. For inefficient reactions, a more sensitive detection method, such as RNase protection, primer extension, or RT-PCR (reverse transcription-polymerase chain reaction), may be required.

  6. Study of nuclear reactions with intense, high-purity, low-energy radioactive ion beams using a versatile multi-configuration dual superconducting-solenoid system

    NASA Astrophysics Data System (ADS)

    Lee, M. Y.; Becchetti, F. D.; O'Donnell, T. W.; Roberts, D. A.; Zimmerman, J. A.; Guimarães, V.; Kolata, J. J.; Peterson, D.; Santi, P.; DeYoung, P. A.; Peaslee, G. F.; Hinnefeld, J. D.

    1999-02-01

    A new device (TwinSol) installed at the Nuclear Structure Laboratory at the University of Notre Dame implements a pair of large-bore 6 T superconducting solenoids for producing relatively pure, high-intensity beams of exotic light nuclei at low-energies (10-80 MeV). Typical beams include 8Li and 6He (T 1/2<1 s). The device efficiently produces, collects and focuses beams onto (or implants into) suitable target foils and test materials. The system uses various combinations of the following detection schemes: XY position sensitive gas counters for time-of-flight and ion ray-tracing; multiple stacks of silicon surface barrier detector telescopes mounted at various angles on a rotating table; 2D position-sensitive silicon detectors (PSDs) for high precision angular measurements; multi-annular, multisectored "CD" detectors for large solid angle (nearly 2π in lab frame), high-collection efficiency (multi-hit) particle detection; and ion-implanted stacks of target foils for off-line detection. Also available are a set of HPGe detectors which will be implemented upon completion of a low-background gamma cave. TwinSol represents an advancement in the application of large-bore superconducting magnet technology, capable of running in persistent mode for weeks without liquid helium (LHe) refill or measurable degradation of magnetic field (<0.1%).

  7. Isospin transport and reaction mechanism in nuclear reactions in the range 20–40 MeV/n

    SciTech Connect

    Barlini, S. Piantelli, S.; Casini, G.; Olmi, A.; Bini, M.; Pasquali, G.; Poggi, G.; Stefanini, A. A.; Valdré, S.; Pastore, G.; Bougault, R.; Lopez, O.; Le Neindre, N.; Parlog, M.; Vient, E.; Bonnet, E.; Chibhi, A.; Frankland, J. D. [GANIL, CEA Borderie, B.; Rivet, M. F. [Institut de Physique Nucléaire, CNRS and others

    2015-10-15

    In recent years, many efforts have been devoted to the investigation of the isospin degree of freedom in nuclear reactions. Comparing systems involving partners with different N/Z, it has been possible to investigate the isospin transport process and its influence on the final products population. This can be then related to the symmetry energy term of the nuclear EOS. From the experimental point of view, this task requires detectors able to measure both charge and mass of the emitted products, in the widest possible range of energy and size of the fragments. With this objective, the FAZIA and GARFIELD+RCo apparatus have been used with success in some recent experiments.

  8. Isospin transport and reaction mechanism in nuclear reactions in the range 20-40 MeV/n

    NASA Astrophysics Data System (ADS)

    Barlini, S.; Piantelli, S.; Casini, G.; Olmi, A.; Bini, M.; Pasquali, G.; Poggi, G.; Stefanini, A. A.; Bougault, R.; Bonnet, E.; Borderie, B.; Chibhi, A.; Frankland, J. D.; Gruyer, D.; Lopez, O.; Le Neindre, N.; Parlog, M.; Rivet, M. F.; Vient, E.; Rosato, E.; Vigilante, M.; Bruno, M.; Marchi, T.; Morelli, L.; Cinausero, M.; Degerlier, M.; Gramegna, F.; Kozik, T.; Twarog, T.; Fabris, D.; Valdré, S.; Pastore, G.

    2015-10-01

    In recent years, many efforts have been devoted to the investigation of the isospin degree of freedom in nuclear reactions. Comparing systems involving partners with different N/Z, it has been possible to investigate the isospin transport process and its influence on the final products population. This can be then related to the symmetry energy term of the nuclear EOS. From the experimental point of view, this task requires detectors able to measure both charge and mass of the emitted products, in the widest possible range of energy and size of the fragments. With this objective, the FAZIA and GARFIELD+RCo apparatus have been used with success in some recent experiments.

  9. The History of Nuclear Energy

    SciTech Connect

    None, None

    1995-01-31

    This is one in a series of publications on nuclear energy. The intent of the series is to present a public overview of various energy sources and it is not intended as an exhaustive treatment of the subject matter. The pamphlet traces the history of discoveries about atoms through more modern-day use of atoms a a valuable source of energy. Included is a detailed chronology and a glossary of terms.

  10. Nuclear Energy. Instructional Materials.

    ERIC Educational Resources Information Center

    Jordan, Kenneth; Thessing, Dan

    This document is one of five learning packets on alternative energy (see note) developed as part of a descriptive curriculum research project in Arkansas. The overall objectives of the learning packets are to improve the level of instruction in the alternative energies by vocational exploration teachers, and to facilitate the integration of new…

  11. Department of Energy Nuclear Energy Standards Program

    SciTech Connect

    Silver, E.G.

    1980-01-01

    The policy with respect to the development and use of standards in the Department of Energy (DOE) programs concerned with maintaining and developing the nuclear option for the civilian sector (both in the form of the currently used light water reactors and for advanced concepts including the Liquid Metal Fast Breeder Reactor), is embodied in a Nuclear Standards Policy, issued in 1978, whose perspectives and philosophy are discussed.

  12. NUCLEAR REACTION MODELING FOR RIA ISOL TARGET DESIGN

    SciTech Connect

    S. MASHNIK; ET AL

    2001-03-01

    Los Alamos scientists are collaborating with researchers at Argonne and Oak Ridge on the development of improved nuclear reaction physics for modeling radionuclide production in ISOL targets. This is being done in the context of the MCNPX simulation code, which is a merger of MCNP and the LAHET intranuclear cascade code, and simulates both nuclear reaction cross sections and radiation transport in the target. The CINDER code is also used to calculate the time-dependent nuclear decays for estimating induced radioactivities. They give an overview of the reaction physics improvements they are addressing, including intranuclear cascade (INC) physics, where recent high-quality inverse-kinematics residue data from GSI have led to INC spallation and fission model improvements; and preequilibrium reactions important in modeling (p,xn) and (p,xnyp) cross sections for the production of nuclides far from stability.

  13. 77 FR 67809 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Department of Energy, Office of Nuclear Energy. ACTION: Notice of Open Meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory Committee (NEAC)....

  14. 75 FR 13269 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Department of Energy, Office of Nuclear Energy. ACTION: Notice of open meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory Committee (NEAC)....

  15. 75 FR 67351 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Office of Nuclear Energy, Department of Energy. ACTION: Notice of open meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory Committee (NEAC)....

  16. 78 FR 76599 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Office of Nuclear Energy, Department of Energy. ACTION: Notice of... that the Nuclear Energy Advisory Committee (NEAC) will be renewed for a two-year period beginning...

  17. 76 FR 67717 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Department of Energy, Office of Nuclear Energy. ACTION: Notice of open meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory Committee (NEAC)....

  18. 77 FR 26274 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Department of Energy, Office of Nuclear Energy. ACTION: Notice of open meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory Committee (NEAC)....

  19. 78 FR 70932 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-27

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Office of Nuclear Energy, Department of Energy. ACTION: Notice of open meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory Committee (NEAC)....

  20. 78 FR 29125 - Nuclear Energy Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee AGENCY: Office of Nuclear Energy, Department of Energy. ACTION: Notice of open meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory Committee (NEAC)....

  1. Photonuclear Reaction Studies at HIγS: Developing the Science of Remote Detection of Nuclear Materials

    NASA Astrophysics Data System (ADS)

    Howell, C. R.

    2015-10-01

    Development of gamma-ray beam interrogation technologies for remote detection of special nuclear materials and isotope analysis requires comprehensive databases of nuclear structure information and gamma-ray induced nuclear reaction observables. Relevant nuclear structure details include the energy, spin and parity of excited states that have significant probability for electromagnetic transition from the ground state, i.e, the angular momentum transferred in the reaction is Δl ≤ 2. This talk will report recent Nuclear Resonance Fluorescence (NRF) measurements to identify and characterize new low-spin states in actinide nuclei at energies from 1 to 4 MeV, which is the energy range most important for remote analysis methods. These measurements are carried out using the nearly mono-energetic linearly polarized gamma-ray beam at the High Intensity Gamma-ray Source (HIγS) at the Triangle Universities Nuclear Laboratory. Also, studies of the (γ, n) reaction on a variety of nuclei with linearly polarized beams at HIγS indicate that this reaction might be used to discern between fissile and non-fissile materials. This work will be described. In addition, an overview will be given of a concept for a next generation laser Compton-backing scattering gamma-ray source to be implemented as an upgrade to increase the beam intensity at HIγS by more than an order of magnitude.

  2. Properties of carbon-based structures synthesized in nuclear reactions induced by bremsstrahlung γ quanta with threshold energy of 10 MeV at helium pressure of 1.1 kbar

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wiśniewski, R.

    2016-07-01

    Helium gas with an initial pressure of about 1.1 kbar inside a high-pressure chamber (HeHPC) has been irradiated by bremsstrahlung γ quanta with a threshold energy of 10 MeV for 1.0 × 105 s produced by an electron-beam current of 22-24 μA. After opening the HeHPC, the residual pressure of helium is equal to 430 bar. Synthesized black foils with a variety of other objects are found inside the HeHPC. They are located on the inner surfaces of the reaction chamber made of high-purity copper (99.99%), the entrance the window of γ quanta made of beryllium bronze and a copper container of nuclear and chemical reaction products. Elemental analysis with the use of scanning electron microscopy and X-ray microprobe analysis has revealed that the foils contain predominantly carbon and small quantities of other elements from carbon to iron. The results are in good agreement with the cycle of investigations of the authors devoted to the γ-quanta irradiation of dense hydrogen and helium gases in the presence (absence) of metals in a reaction chamber.

  3. The carbon-based structures synthesized through nuclear reactions in helium at 1.1 kbar pressure under irradiation with braking γ-rays of 10 MeV threshold energy

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wisniewski, R.; Wilczynska-Kitowska, T.

    2015-01-01

    A helium high-pressure chamber (HeHPC), made from beryllium bronze, filled with gaseous helium at an initial pressure of about 1.1 kbar was irradiated by braking γ-rays of 10 MeV threshold energy during 1.0×105 \\text{s} at an electron beam current 22\\text-24 μ \\text{A} . Before opening of the chamber, the residual pressure inside was equal to 430 bar. Synthesized foils of black colour and other multiple objects were found inside the HeHPC at the inner surfaces of the reaction chamber made of high-purity copper, at the entrance window for γ-rays of beryllium bronze, and at the copper collector of nuclear and chemical reaction products. The element analysis using scanning electron microscopy (SEM) and microprobe roentgen analysis (MPRA) allowed us to establish that the foils were predominantly made of carbon and smaller quantities of other elements from carbon to iron. The developed approach agrees well with a series of studies carried out by the authors where dense hydrogen and deuterium gases are acted on by γ-rays in the presence or absence of metals in the reaction chamber.

  4. RIPL - Reference Input Parameter Library for Calculation of Nuclear Reactions and Nuclear Data Evaluations

    SciTech Connect

    Capote, R. , E-Mail: r.capotenoy@iaea.org; Herman, M.; Oblozinsky, P.; Young, P.G.; Goriely, S.; Belgya, T.; Ignatyuk, A.V.; Koning, A.J.; Hilaire, S.; Plujko, V.A.; Avrigeanu, M.; Bersillon, O.; Chadwick, M.B.; Fukahori, T.; Ge, Zhigang; Han, Yinlu; Kailas, S.; Kopecky, J.; Maslov, V.M.; Reffo, G.

    2009-12-15

    We describe the physics and data included in the Reference Input Parameter Library, which is devoted to input parameters needed in calculations of nuclear reactions and nuclear data evaluations. Advanced modelling codes require substantial numerical input, therefore the International Atomic Energy Agency (IAEA) has worked extensively since 1993 on a library of validated nuclear-model input parameters, referred to as the Reference Input Parameter Library (RIPL). A final RIPL coordinated research project (RIPL-3) was brought to a successful conclusion in December 2008, after 15 years of challenging work carried out through three consecutive IAEA projects. The RIPL-3 library was released in January 2009, and is available on the Web through (http://www-nds.iaea.org/RIPL-3/). This work and the resulting database are extremely important to theoreticians involved in the development and use of nuclear reaction modelling (ALICE, EMPIRE, GNASH, UNF, TALYS) both for theoretical research and nuclear data evaluations. The numerical data and computer codes included in RIPL-3 are arranged in seven segments: MASSES contains ground-state properties of nuclei for about 9000 nuclei, including three theoretical predictions of masses and the evaluated experimental masses of Audi et al. (2003). DISCRETE LEVELS contains 117 datasets (one for each element) with all known level schemes, electromagnetic and {gamma}-ray decay probabilities available from ENSDF in October 2007. NEUTRON RESONANCES contains average resonance parameters prepared on the basis of the evaluations performed by Ignatyuk and Mughabghab. OPTICAL MODEL contains 495 sets of phenomenological optical model parameters defined in a wide energy range. When there are insufficient experimental data, the evaluator has to resort to either global parameterizations or microscopic approaches. Radial density distributions to be used as input for microscopic calculations are stored in the MASSES segment. LEVEL DENSITIES contains

  5. RIPL-Reference Input Parameter Library for Calculation of Nuclear Reactions and Nuclear Data Evaluations

    SciTech Connect

    Capote, R.; Herman, M.; Capote,R.; Herman,M.; Oblozinsky,P.; Young,P.G.; Goriely,S.; Belgy,T.; Ignatyuk,A.V.; Koning,A.J.; Hilaire,S.; Pljko,V.A.; Avrigeanu,M.; Bersillon,O.; Chadwick,M.B.; Fukahori,T.; Ge, Zhigang; Han,Yinl,; Kailas,S.; Kopecky,J.; Maslov,V.M.; Reffo,G.; Sin,M.; Soukhovitskii,E.Sh.; Talou,P

    2009-12-01

    We describe the physics and data included in the Reference Input Parameter Library, which is devoted to input parameters needed in calculations of nuclear reactions and nuclear data evaluations. Advanced modelling codes require substantial numerical input, therefore the International Atomic Energy Agency (IAEA) has worked extensively since 1993 on a library of validated nuclear-model input parameters, referred to as the Reference Input Parameter Library (RIPL). A final RIPL coordinated research project (RIPL-3) was brought to a successful conclusion in December 2008, after 15 years of challenging work carried out through three consecutive IAEA projects. The RIPL-3 library was released in January 2009, and is available on the Web through http://www-nds.iaea.org/RIPL-3/. This work and the resulting database are extremely important to theoreticians involved in the development and use of nuclear reaction modelling (ALICE, EMPIRE, GNASH, UNF, TALYS) both for theoretical research and nuclear data evaluations. The numerical data and computer codes included in RIPL-3 are arranged in seven segments: MASSES contains ground-state properties of nuclei for about 9000 nuclei, including three theoretical predictions of masses and the evaluated experimental masses of Audi et al. (2003). DISCRETE LEVELS contains 117 datasets (one for each element) with all known level schemes, electromagnetic and {gamma}-ray decay probabilities available from ENSDF in October 2007. NEUTRON RESONANCES contains average resonance parameters prepared on the basis of the evaluations performed by Ignatyuk and Mughabghab. OPTICAL MODEL contains 495 sets of phenomenological optical model parameters defined in a wide energy range. When there are insufficient experimental data, the evaluator has to resort to either global parameterizations or microscopic approaches. Radial density distributions to be used as input for microscopic calculations are stored in the MASSES segment. LEVEL DENSITIES contains

  6. RIPL - Reference Input Parameter Library for Calculation of Nuclear Reactions and Nuclear Data Evaluations

    NASA Astrophysics Data System (ADS)

    Capote, R.; Herman, M.; Obložinský, P.; Young, P. G.; Goriely, S.; Belgya, T.; Ignatyuk, A. V.; Koning, A. J.; Hilaire, S.; Plujko, V. A.; Avrigeanu, M.; Bersillon, O.; Chadwick, M. B.; Fukahori, T.; Ge, Zhigang; Han, Yinlu; Kailas, S.; Kopecky, J.; Maslov, V. M.; Reffo, G.; Sin, M.; Soukhovitskii, E. Sh.; Talou, P.

    2009-12-01

    We describe the physics and data included in the Reference Input Parameter Library, which is devoted to input parameters needed in calculations of nuclear reactions and nuclear data evaluations. Advanced modelling codes require substantial numerical input, therefore the International Atomic Energy Agency (IAEA) has worked extensively since 1993 on a library of validated nuclear-model input parameters, referred to as the Reference Input Parameter Library (RIPL). A final RIPL coordinated research project (RIPL-3) was brought to a successful conclusion in December 2008, after 15 years of challenging work carried out through three consecutive IAEA projects. The RIPL-3 library was released in January 2009, and is available on the Web through http://www-nds.iaea.org/RIPL-3/. This work and the resulting database are extremely important to theoreticians involved in the development and use of nuclear reaction modelling (ALICE, EMPIRE, GNASH, UNF, TALYS) both for theoretical research and nuclear data evaluations. The numerical data and computer codes included in RIPL-3 are arranged in seven segments: MASSES contains ground-state properties of nuclei for about 9000 nuclei, including three theoretical predictions of masses and the evaluated experimental masses of Audi et al. (2003). DISCRETE LEVELS contains 117 datasets (one for each element) with all known level schemes, electromagnetic and γ-ray decay probabilities available from ENSDF in October 2007. NEUTRON RESONANCES contains average resonance parameters prepared on the basis of the evaluations performed by Ignatyuk and Mughabghab. OPTICAL MODEL contains 495 sets of phenomenological optical model parameters defined in a wide energy range. When there are insufficient experimental data, the evaluator has to resort to either global parameterizations or microscopic approaches. Radial density distributions to be used as input for microscopic calculations are stored in the MASSES segment. LEVEL DENSITIES contains

  7. Neutrino nuclear responses for double beta decays and astro neutrinos by charge exchange reactions

    NASA Astrophysics Data System (ADS)

    Ejiri, Hiroyasu

    2014-09-01

    Neutrino nuclear responses are crucial for neutrino studies in nuclei. Charge exchange reactions (CER) are shown to be used to study charged current neutrino nuclear responses associated with double beta decays(DBD)and astro neutrino interactions. CERs to be used are high energy-resolution (He3 ,t) reactions at RCNP, photonuclear reactions via IAR at NewSUBARU and muon capture reactions at MUSIC RCNP and MLF J-PARC. The Gamow Teller (GT) strengths studied by CERs reproduce the observed 2 neutrino DBD matrix elements. The GT and spin dipole (SD) matrix elements are found to be reduced much due to the nucleon spin isospin correlations and the non-nucleonic (delta isobar) nuclear medium effects. Impacts of the reductions on the DBD matrix elements and astro neutrino interactions are discussed.

  8. Computed potential energy surfaces for chemical reactions

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.

    1994-01-01

    Quantum mechanical methods have been used to compute potential energy surfaces for chemical reactions. The reactions studied were among those believed to be important to the NASP and HSR programs and included the recombination of two H atoms with several different third bodies; the reactions in the thermal Zeldovich mechanism; the reactions of H atom with O2, N2, and NO; reactions involved in the thermal De-NO(x) process; and the reaction of CH(squared Pi) with N2 (leading to 'prompt NO'). These potential energy surfaces have been used to compute reaction rate constants and rates of unimolecular decomposition. An additional application was the calculation of transport properties of gases using a semiclassical approximation (and in the case of interactions involving hydrogen inclusion of quantum mechanical effects).

  9. Computed potential energy surfaces for chemical reactions

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.

    1990-01-01

    The objective was to obtain accurate potential energy surfaces (PES's) for a number of reactions which are important in the H/N/O combustion process. The interest in this is centered around the design of the SCRAM jet engine for the National Aerospace Plane (NASP), which was envisioned as an air-breathing hydrogen-burning vehicle capable of reaching velocities as large as Mach 25. Preliminary studies indicated that the supersonic flow in the combustor region of the scram jet engine required accurate reaction rate data for reactions in the H/N/O system, some of which was not readily available from experiment. The most important class of combustion reactions from the standpoint of the NASP project are radical recombinaton reactions, since these reactions result in most of the heat release in the combustion process. Theoretical characterizations of the potential energy surfaces for these reactions are presented and discussed.

  10. New measurements of the astrophysical S factor for {sup 12}C(p,{gamma}){sup 13}N reaction at low energies and the asymptotic normalization coefficient (nuclear vertex constant) for the p+{sup 12}C{yields}{sup 13}N reaction

    SciTech Connect

    Burtebaev, N.; Zazulin, D. M.; Igamov, S. B.; Yarmukhamedov, R.; Peterson, R. J.

    2008-09-15

    New measurements of differential and total cross sections for the {sup 12}C(p,{gamma}){sup 13}N reaction have been made at beam energies of E{sub p}=354,390,460,463,565,750, and 1061 keV. Analysis of the astrophysical S factor S(E) for the {sup 12}C(p,{gamma}){sup 13}N reaction at low energies and of the reaction rates has been carried out within the R-matrix approach by using the previously measured nuclear vertex constant (or the respective asymptotic normalization coefficient) for the virtual decay {sup 13}N{yields}p+{sup 12}C to fix the direct capture part of the amplitude in S(E). It is demonstrated that the R-matrix approach, using the measured asymptotic normalization coefficient, can be employed as an ideal tool, minimizing the uncertainties associated with a calculation of the direct capture cross section of the {sup 12}C(p,{gamma}){sup 13}N reaction at extremely low energies. New information on the proton and {gamma} width for the first excited state of {sup 13}N is obtained.

  11. Answers to Questions: Nuclear Energy.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC. Nuclear Energy Office.

    Electricity is an increasingly important part of our everyday lives. Its versatility allows one to heat, cool, and light homes; cook meals; watch television; listen to music; power computers; make medical diagnosis and treatment; explore the vastness of space; and study the tiniest molecules. Nuclear energy, second to coal, surpasses natural gas,…

  12. Low energy ion-molecule reactions

    SciTech Connect

    Farrar, J.M.

    1993-12-01

    This project is concerned with elucidating the dynamics of elementary ion-molecule reactions at collision energies near and below 1 eV. From measurements of the angular and energy distributions of the reaction products, one can infer intimathe details about the nature of collisions leading to chemical reaction, the geometries and lifetimes of intermediate complexes that govern the reaction dynamics, and the collision energy dependence of these dynamical features. The author employs crossed-beam low energy mass spectrometry technology developed over the last several years, with the focus of current research on proton transfer and hydrogen atom transfer reactions of te O{sup {minus}} ion with species such as HF, H{sub 2}O, and NH{sub 3}.

  13. Research in Heavy Ion Nuclear Reactions

    SciTech Connect

    Petitt, G.A.; Nelson, W.H.; He, Xiaochun; Lee, W.

    1999-04-14

    This is the final progress report for the experimental nuclear physics program at Georgia State University (GSU) under the leadership of Gus Petitt. In June, 1996, Professor Petitt retired for health reasons and the DOE contract was extended for another year to enable the group to continue it's work. This year has been a productive one. The group has been heavily involved in the E866 experiment at Fermilab where we have taken on the responsibility of developing a new level-3 trigger for the experiment. Bill Lee, the graduate student in our group expects to obtain his thesis data from the run extension currently in progress, which focuses on the A dependence of J/{psi}'s and {Upsilon}'s from beryllium, tungsten, and iron targets. In the past year and a half the GSU group has led the development of a new level-3 software trigger system for E866. Our work on this project is described.

  14. A study of heavy-heavy nuclear reactions. [nuclear research/nuclear particles

    NASA Technical Reports Server (NTRS)

    Khandelwal, G. S.

    1975-01-01

    Calculations are presented for the reaction products in high energy collisions and of the atmospheric transport of particles such as protons, neutrons and other nucleons. The magnetic moments of charmed baryons are examined. Total cross sections which are required for cosmic heavy ion transport and shielding studies are also examined.

  15. Modeling Proton- and Light Ion-Induced Reactions at Low Energies in the MARS15 Code

    SciTech Connect

    Rakhno, I. L.; Mokhov, N. V.; Gudima, K. K.

    2015-04-25

    An implementation of both ALICE code and TENDL evaluated nuclear data library in order to describe nuclear reactions induced by low-energy projectiles in the Monte Carlo code MARS15 is presented. Comparisons between results of modeling and experimental data on reaction cross sections and secondary particle distributions are shown.

  16. EXFOR SYSTEMS MANUAL NUCLEAR REACTION DATA EXCHANGE FORMAT.

    SciTech Connect

    MCLANE,V.; NUCLEAR DATA CENTER NETWORK

    2000-05-19

    EXFOR is an exchange format designed to allow transmission of nuclear reaction data between the members of the Nuclear Data Centers Network. This document has been written for use by the members of the Network and includes matters of procedure and protocol, as well as detailed rules for the compilation of data. Users may prefer to consult EXFOR Basics' for a brief description of the format.

  17. U.S. nuclear reaction data program in support of basic research

    SciTech Connect

    Bhat, M.R.; Chadwick, M.B.; Smith, M.S.

    1998-03-01

    Information about the US Nuclear Reaction Data Network (USNRDN) such as its members, work in progress, summaries of meetings, and organizational details may be found in its WWW Homepage. This paper is an overview of the data support provided by the network for basic research in nuclear astrophysics, radioactive ion beams, high energy heavy ion and electron interactions and related activities involving all aspects of data stewardship.

  18. Dependence of X-Ray Burst Models on Nuclear Reaction Rates

    NASA Astrophysics Data System (ADS)

    Cyburt, R. H.; Amthor, A. M.; Heger, A.; Johnson, E.; Keek, L.; Meisel, Z.; Schatz, H.; Smith, K.

    2016-10-01

    X-ray bursts are thermonuclear flashes on the surface of accreting neutron stars, and reliable burst models are needed to interpret observations in terms of properties of the neutron star and the binary system. We investigate the dependence of X-ray burst models on uncertainties in (p, γ), (α, γ), and (α, p) nuclear reaction rates using fully self-consistent burst models that account for the feedbacks between changes in nuclear energy generation and changes in astrophysical conditions. A two-step approach first identified sensitive nuclear reaction rates in a single-zone model with ignition conditions chosen to match calculations with a state-of-the-art 1D multi-zone model based on the Kepler stellar evolution code. All relevant reaction rates on neutron-deficient isotopes up to mass 106 were individually varied by a factor of 100 up and down. Calculations of the 84 changes in reaction rate with the highest impact were then repeated in the 1D multi-zone model. We find a number of uncertain reaction rates that affect predictions of light curves and burst ashes significantly. The results provide insights into the nuclear processes that shape observables from X-ray bursts, and guidance for future nuclear physics work to reduce nuclear uncertainties in X-ray burst models.

  19. Nuclear Reactions and Stellar Evolution: Unified Dynamics

    SciTech Connect

    Bauer, W.; Strother, T.

    2007-10-26

    Motivated by the success of kinetic theory in the description of observables in intermediate and high energy heavy ion collisions, we use kinetic theory to model the dynamics of collapsing iron cores in type II supernova explosions. The algorithms employed to model the collapse, some preliminary results and predictions, and the future of the code are discussed.

  20. Development of the Experimental Photo-Nuclear Reaction Database in Hokkaido University

    NASA Astrophysics Data System (ADS)

    Makinaga, A.

    2015-10-01

    Nuclear databases are important tools to apply nuclear phenomena to various fields of nuclear engineering. It is now recognized that the databases must be further developed for photo-nuclear reaction data for nuclear security, safety and nonproliferation applications. Hokkaido University Nuclear Reaction Data Centre (JCPRG) has contributed to the Experimental Nuclear Reaction Data Library (EXFOR) which is developed by the International Network of Nuclear Reaction Data Centres under coordination by IAEA. We report here on the recent compilation of the nuclear data files for the photonuclear reaction.

  1. Fission Activities of the Nuclear Reactions Group in Uppsala

    NASA Astrophysics Data System (ADS)

    Al-Adili, A.; Alhassan, E.; Gustavsson, C.; Helgesson, P.; Jansson, K.; Koning, A.; Lantz, M.; Mattera, A.; Prokofiev, A. V.; Rakopoulos, V.; Sjöstrand, H.; Solders, A.; Tarrío, D.; Österlund, M.; Pomp, S.

    This paper highlights some of the main activities related to fission of the nuclear reactions group at Uppsala University. The group is involved for instance in fission yield experiments at the IGISOL facility, cross-section measurements at the NFS facility, as well as fission dynamics studies at the IRMM JRC-EC. Moreover, work is ongoing on the Total Monte Carlo (TMC) methodology and on including the GEF fission code into the TALYS nuclear reaction code. Selected results from these projects are discussed.

  2. Towards many-body based nuclear reaction modelling

    NASA Astrophysics Data System (ADS)

    Hilaire, Stéphane; Goriely, Stéphane

    2016-06-01

    The increasing need for cross sections far from the valley of stability poses a challenge for nuclear reaction models. So far, predictions of cross sections have relied on more or less phenomenological approaches, depending on parameters adjusted to available experimental data or deduced from systematic expressions. While such predictions are expected to be reliable for nuclei not too far from the experimentally known regions, it is clearly preferable to use more fundamental approaches, based on sound physical principles, when dealing with very exotic nuclei. Thanks to the high computer power available today, all the ingredients required to model a nuclear reaction can now be (and have been) microscopically (or semi-microscopically) determined starting from the information provided by a nucleon-nucleon effective interaction. This concerns nuclear masses, optical model potential, nuclear level densities, photon strength functions, as well as fission barriers. All these nuclear model ingredients, traditionally given by phenomenological expressions, now have a microscopic counterpart implemented in the TALYS nuclear reaction code. We are thus now able to perform fully microscopic cross section calculations. The quality of these ingredients and the impact of using them instead of the usually adopted phenomenological parameters will be discussed. Perspectives for the coming years will be drawn on the improvements one can expect.

  3. Finding reaction paths using the potential energy as reaction coordinate.

    PubMed

    Aguilar-Mogas, Antoni; Giménez, Xavier; Bofill, Josep Maria

    2008-03-14

    The intrinsic reaction coordinate curve (IRC), normally proposed as a representation of a reaction path, is parametrized as a function of the potential energy rather than the arc-length. This change in the parametrization of the curve implies that the values of the energy of the potential energy surface points, where the IRC curve is located, play the role of reaction coordinate. We use Caratheodory's relation to derive in a rigorous manner the proposed parametrization of the IRC path. Since this Caratheodory's relation is the basis of the theory of calculus of variations, then this fact permits to reformulate the IRC model from this mathematical theory. In this mathematical theory, the character of the variational solution (either maximum or minimum) is given through the Weierstrass E-function. As proposed by Crehuet and Bofill [J. Chem. Phys. 122, 234105 (2005)], we use the minimization of the Weierstrass E-function, as a function of the potential energy, to locate an IRC path between two minima from an arbitrary curve on the potential energy surface, and then join these two minima. We also prove, from the analysis of the Weierstrass E-function, the mathematical bases for the algorithms proposed to locate the IRC path. The proposed algorithm is applied to a set of examples. Finally, the algorithm is used to locate a discontinuous, or broken, IRC path, namely, when the path connects two first order saddle points through a valley-ridged inflection point. PMID:18345872

  4. Finding reaction paths using the potential energy as reaction coordinate

    NASA Astrophysics Data System (ADS)

    Aguilar-Mogas, Antoni; Giménez, Xavier; Bofill, Josep Maria

    2008-03-01

    The intrinsic reaction coordinate curve (IRC), normally proposed as a representation of a reaction path, is parametrized as a function of the potential energy rather than the arc-length. This change in the parametrization of the curve implies that the values of the energy of the potential energy surface points, where the IRC curve is located, play the role of reaction coordinate. We use Carathéodory's relation to derive in a rigorous manner the proposed parametrization of the IRC path. Since this Carathéodory's relation is the basis of the theory of calculus of variations, then this fact permits to reformulate the IRC model from this mathematical theory. In this mathematical theory, the character of the variational solution (either maximum or minimum) is given through the Weierstrass E-function. As proposed by Crehuet and Bofill [J. Chem. Phys. 122, 234105 (2005)], we use the minimization of the Weierstrass E-function, as a function of the potential energy, to locate an IRC path between two minima from an arbitrary curve on the potential energy surface, and then join these two minima. We also prove, from the analysis of the Weierstrass E-function, the mathematical bases for the algorithms proposed to locate the IRC path. The proposed algorithm is applied to a set of examples. Finally, the algorithm is used to locate a discontinuous, or broken, IRC path, namely, when the path connects two first order saddle points through a valley-ridged inflection point.

  5. Nuclear methods in environmental and energy research

    SciTech Connect

    Vogt, J R

    1980-01-01

    A total of 75 papers were presented on nuclear methods for analysis of environmental and biological samples. Sessions were devoted to software and mathematical methods; nuclear methods in atmospheric and water research; nuclear and atomic methodology; nuclear methods in biology and medicine; and nuclear methods in energy research.

  6. Cross Sections Calculations of ( d, t) Nuclear Reactions up to 50 MeV

    NASA Astrophysics Data System (ADS)

    Tel, E.; Yiğit, M.; Tanır, G.

    2013-04-01

    In nuclear fusion reactions two light atomic nuclei fuse together to form a heavier nucleus. Fusion power is the power generated by nuclear fusion processes. In contrast with fission power, the fusion reaction processes does not produce radioactive nuclides. The fusion will not produce CO2 or SO2. So the fusion energy will not contribute to environmental problems such as particulate pollution and excessive CO2 in the atmosphere. Fusion powered electricity generation was initially believed to be readily achievable, as fission power had been. However, the extreme requirements for continuous reactions and plasma containment led to projections being extended by several decades. In 2010, more than 60 years after the first attempts, commercial power production is still believed to be unlikely before 2050. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. In the fusion reactor, tritium self-sufficiency must be maintained for a commercial power plant. Therefore, for self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of ( d, t) nuclear reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. Since the experimental data of charged particle induced reactions are scarce, self-consistent calculation and analyses using nuclear theoretical models are very important. In this study, ( d, t) cross sections for target nuclei 19F, 50Cr, 54Fe, 58Ni, 75As, 89Y, 90Zr, 107Ag, 127I, 197Au and 238U have been investigated up to 50 MeV deuteron energy. The excitation functions for ( d, t) reactions have been calculated by pre-equilibrium reaction mechanism. Calculation results have been also compared with the available measurements in

  7. Dynamic Analysis of Nuclear Energy System Strategies

    2004-06-17

    DANESS is an integrated process model for nuclear energy systems allowing the simulation of multiple reactors and fuel cycles in a continuously changing nuclear reactor park configuration. The model is energy demand driven and simulates all nuclear fuel cycle facilites, up to 10 reactors and fuels. Reactor and fuel cycle facility history are traced and the cost of generating energy is calculated per reactor and for total nuclear energy system. The DANESS model aims atmore » performing dynamic systems analysis of nuclear energy development used for integrated analysis of development paths for nuclear energy, parameter scoping for new nuclear energy systems, economic analysis of nuclear energy, government role analysis, and education.« less

  8. Proposal for New Experimental Tests of the Bose-Einstein Condensation Mechanism for Low-Energy Nuclear Reaction and Transmutation Processes in Deuterium Loaded - and Nano-Scale Cavities

    NASA Astrophysics Data System (ADS)

    Kim, Yeong E.; Koltick, David S.; Reifenberger, Ronald G.; Zubarev, Alexander L.

    2006-02-01

    Most of experimental results of low-energy nuclear reaction (LENR) reported so far cannot be reproduced on demand. There have been persistent experimental results indicating that the LENR and transmutation processes in condensed matters (LENRTPCM) are surface phenomena rather than bulk phenomena. Recently proposed Bose-Einstein condensation (BEC) mechanism may provide a suitable theoretical description of the surface phenomena. New experiments are proposed and described for testing the BEC mechanism for LENR and transmutation processes in micro- and nano-scale traps. (1) We propose the use of micro- or nano-porous conducting materials as a cathode in electrolysis experiments with heavy water with or without Li in order to stabilize the active surface spots and to enhance the effect for the purpose of improving the reproducibility of excess heat generation and nuclear emission. (2) We propose new experimental tests of the BEC mechanism by measuring the pressure and temperature dependence of LENR events using deuterium gas and these deuterated metals with or without Li. If the LENRTPCM are surface phenomena, the proposed use of micro-/nano-scale porous materials is expected to enhance and scale up the LENRTPCM effects by many order of magnitude, and thus may lead to better reproductivity and theoretical understanding of the phenomena.

  9. Investigations of nuclear structure and nuclear reactions induced by complex projectiles

    SciTech Connect

    Sarantites, D.G.

    1991-01-01

    The research program of our group touches five areas of nuclear physics: (1) Nuclear structure studies at high spin; (2) Studies at the interface between structure and reactions; (3) Production and study of hot nuclei; (4) Incomplete fusion and fragmentation reactions; and (5) Development and use of novel techniques and instrumentation in the above areas of research. The papers from these areas are discussed in this report.

  10. Indirect measurement of nuclear reactions of astrophysical interest

    SciTech Connect

    Liu, W. P.; Li, Z. H.; Bai, X. X.; Wang, Y. B.; Guo, B.; Lian, G.; Su, J.; Zeng, S.; Wang, B. X.; Yan, S. Q.; Li, Y. J.; Li, E. T.; Jin, S. J.

    2010-05-12

    Systematic indirect measurements of nuclear astrophysical reactions using the unstable ion beam facility GIRAFFE in CIAE were performed. We have measured the angular distributions of transfer reactions, such as {sup 8}Li(d,p){sup 9}Li, {sup 8}Li(d,n){sup 9}Be and {sup 8}Li(p,d){sup 7}Li in inverse kinematics, and derived the astrophysical S-factors or reaction rates for {sup 8}Li(n,gamma){sup 9}Li and {sup 8}Li(p,gamma){sup 9}Be by using asymptotic normalization coefficient (ANC) or spectroscopic factor methods.

  11. The ``light-est'' of all Projectiles: Nuclear Structure Studies Using Photonuclear Reactions

    NASA Astrophysics Data System (ADS)

    Pietralla, Norbert

    2014-03-01

    Nuclear reactions induced by photons have had and continue to have a large impact on the course of nuclear physics. Photons interact purely electromagnetically with the atomic nucleus and induce minimal momentum transfer at given excitation energy. Photonuclear reaction processes can be expanded in terms of QED and photonuclear excitations are by far dominated by one-step processes. They allow for a model independent measurement of nuclear observables and, hence, for a clean characterization of effective nuclear forces. Apart from the pioneering photonuclear reactions by Bothe and Gentner in the 1930s, bremsstrahlung has been used most widely as an intense source of gamma-rays for photonuclear reactions from the 1940s until today. The nuclear dipole strength distribution has largely been mapped out at bremsstrahlung facilities. While the continuous-energy distribution of bremsstrahlung photons offers a complete view of the spectrum of photonuclear excitations, it suffers from a poor sensitivity to specific energy intervals. Intense, energy-tunable, quasi-monochromatic gamma-ray beams from laser-Compton backscattering processes have revolutionized the field of photonuclear reactions for the last ten years. A set of new techniques is under development and new information on fundamental nuclear modes, such as the IVGDR, IVGQR, Pygmy Dipole Resonance, and the Scissors Mode, has recently been obtained. We will attempt to give a brief overview of the state of the art and dare an outlook at the research opportunities at the next generation of gamma-ray facilities under construction in the U.S. and Europe. Supported by the DFG under grant No. SFB634.

  12. A Laboratory Experiment on the Statistical Theory of Nuclear Reactions

    ERIC Educational Resources Information Center

    Loveland, Walter

    1971-01-01

    Describes an undergraduate laboratory experiment on the statistical theory of nuclear reactions. The experiment involves measuring the relative cross sections for formation of a nucleus in its meta stable excited state and its ground state by applying gamma-ray spectroscopy to an irradiated sample. Involves 3-4 hours of laboratory time plus…

  13. What can nuclear energy do for society.

    NASA Technical Reports Server (NTRS)

    Rom, F. E.

    1971-01-01

    Nuclear fuel is a compact and abundant source of energy. Its cost per unit of energy is less than that of fossil fuel. Disadvantages of nuclear fuel are connected with the high cost of capital equipment required for releasing nuclear energy and the heavy weight of the necessary shielding. In the case of commercial electric power production and marine propulsion the advantages have outweighed the disadvantages. It is pointed out that nuclear commercial submarines have certain advantages compared to surface ships. Nuclear powerplants might make air-cushion vehicles for transoceanic ranges feasible. The problems and advantages of a nuclear aircraft are discussed together with nuclear propulsion for interplanetary space voyages.

  14. What can nuclear energy do for society?

    NASA Technical Reports Server (NTRS)

    Rom, F. E.

    1971-01-01

    The utilization of nuclear energy and the predicted impact of future uses of nuclear energy are discussed. Areas of application in electric power production and transportation methods are described. It is concluded that the need for many forms of nuclear energy will become critical as the requirements for power to supply an increasing population are met.

  15. Energy distribution among reaction products. V.

    NASA Technical Reports Server (NTRS)

    Anlauf, K. G.; Horne, D. S.; Macdonald, R. G.; Polanyi, J. C.; Woodall, K. B.

    1972-01-01

    Discussion of three reactions, one point of theoretical interest being the predicted correlation between barrier height and barrier location. The H + Br 2 reaction having a lower activation barrier than H + Cl 2, should have an earlier barrier, and hence a greater percentage attractive energy release and higher efficiency of vibrational excitation. Information is developed concerning the effect of isotopic substitution in the pair of reactions H + Cl 2 and D + Cl 2. The 'arrested relaxation' method was used. Essentially, the method involves reacting two diffuse reagent beams in a reaction vessel with background pressure less than 0.001 torr, and with walls cooled by liquid nitrogen or liquid helium.

  16. Nuclear quantum effects and kinetic isotope effects in enzyme reactions.

    PubMed

    Vardi-Kilshtain, Alexandra; Nitoker, Neta; Major, Dan Thomas

    2015-09-15

    Enzymes are extraordinarily effective catalysts evolved to perform well-defined and highly specific chemical transformations. Studying the nature of rate enhancements and the mechanistic strategies in enzymes is very important, both from a basic scientific point of view, as well as in order to improve rational design of biomimetics. Kinetic isotope effect (KIE) is a very important tool in the study of chemical reactions and has been used extensively in the field of enzymology. Theoretically, the prediction of KIEs in condensed phase environments such as enzymes is challenging due to the need to include nuclear quantum effects (NQEs). Herein we describe recent progress in our group in the development of multi-scale simulation methods for the calculation of NQEs and accurate computation of KIEs. We also describe their application to several enzyme systems. In particular we describe the use of combined quantum mechanics/molecular mechanics (QM/MM) methods in classical and quantum simulations. The development of various novel path-integral methods is reviewed. These methods are tailor suited to enzyme systems, where only a few degrees of freedom involved in the chemistry need to be quantized. The application of the hybrid QM/MM quantum-classical simulation approach to three case studies is presented. The first case involves the proton transfer in alanine racemase. The second case presented involves orotidine 5'-monophosphate decarboxylase where multidimensional free energy simulations together with kinetic isotope effects are combined in the study of the reaction mechanism. Finally, we discuss the proton transfer in nitroalkane oxidase, where the enzyme employs tunneling as a catalytic fine-tuning tool. PMID:25769515

  17. Nuclear quantum effects and kinetic isotope effects in enzyme reactions.

    PubMed

    Vardi-Kilshtain, Alexandra; Nitoker, Neta; Major, Dan Thomas

    2015-09-15

    Enzymes are extraordinarily effective catalysts evolved to perform well-defined and highly specific chemical transformations. Studying the nature of rate enhancements and the mechanistic strategies in enzymes is very important, both from a basic scientific point of view, as well as in order to improve rational design of biomimetics. Kinetic isotope effect (KIE) is a very important tool in the study of chemical reactions and has been used extensively in the field of enzymology. Theoretically, the prediction of KIEs in condensed phase environments such as enzymes is challenging due to the need to include nuclear quantum effects (NQEs). Herein we describe recent progress in our group in the development of multi-scale simulation methods for the calculation of NQEs and accurate computation of KIEs. We also describe their application to several enzyme systems. In particular we describe the use of combined quantum mechanics/molecular mechanics (QM/MM) methods in classical and quantum simulations. The development of various novel path-integral methods is reviewed. These methods are tailor suited to enzyme systems, where only a few degrees of freedom involved in the chemistry need to be quantized. The application of the hybrid QM/MM quantum-classical simulation approach to three case studies is presented. The first case involves the proton transfer in alanine racemase. The second case presented involves orotidine 5'-monophosphate decarboxylase where multidimensional free energy simulations together with kinetic isotope effects are combined in the study of the reaction mechanism. Finally, we discuss the proton transfer in nitroalkane oxidase, where the enzyme employs tunneling as a catalytic fine-tuning tool.

  18. Delayed gamma radiation from lightning induced nuclear reactions

    NASA Astrophysics Data System (ADS)

    Greenfield, M. B.; Sakuma, K.; Ikeda, Y.; Kubo, K.

    2004-03-01

    An increase in atmospheric gamma radiation observed with NaI and Ge detectors positioned about 15 m above ground was observed following natural lightning near Tokyo, Japan [1]. Background subtracted gamma ray rates GRR following numerous lightning strokes observed since 2001 persisted for a few hours and subsequently decayed with a half-life of about 50 minutes. Using a 3x3 Ge detector, with 2 KeV resolution, positioned about 2 m from one of the NaI detectors increases in GRR were observed minutes after the onset of lightning with a delayed 50 min exponential decay. Although most of the increase in activity occured at less than a few 100 KeV, on July 11, 2003 a 1267 +/-2 KeV line was observed. Although the statistics of this event were poor, the appearance of this line with an exponential decay of 50 min half-life suggests the possibility that it may be due to 39Cl (1267 MeV; half-life = 55.5 min) via the 40Ar(gamma,p)39Cl, 40Ar(p,2p)39Cl and/or 40Ar(n,d)39Cl reactions. Observations of > 10 MeV gamma rays observed in NaI detectors within 10s of meters from and coincident with rocket-triggered lightning at the International Center for Lightning Research and Testing suggest that charged particles accelerated in intense electric fields associated with lightning give rise to photons with sufficient energy to initiate nuclear reactions [2]. Further work to explain the cause of this anomalous activity is underway using natural and triggered lightning. 1. M. B. Greenfield et al., Journal of Applied Physics 93 no. 3 (2003) pp 1839-184. 2. J. R. Dwyer et al., Science 299, (2003), pp 694-697 and recent communications

  19. Plastic foils as primary hydrogen standards for nuclear reaction analysis

    NASA Astrophysics Data System (ADS)

    Rudolph, W.; Bauer, C.; Brankoff, K.; Grambole, D.; Grötzschel, R.; Heiser, C.; Herrmann, F.

    1986-04-01

    Plastic materials like polypropylene, polyester (Mylar) and polycarbonate (Lexan or Makrofol E) contain large amounts of hydrogen and their compositions are well known. However, these materials are not stable during ion bombardment. Using the 1H( 15N,αγ) 12C and 1H( 19F, αγ) 16O nuclear resonance reaction at energies EN = 6.50 MeV and EF = 6.83 MeV, respectively, we have investigated the behaviour of plastic foils during 15N and 19F ion bombardment. By means of a rotating sample holder low current densities of 1-2 {nA}/{cm 2} and large irradiated foil areas of up to 10 cm 2 were realized. Under these measuring conditions the γ-ray yields change only slightly and the initial yields, which correspond to the known compositions of the foils, can be determined with good accuracy. In this way the plastic foils can be used as primary standards for hydrogen content calibration. The method was employed to calibrate an a-Si(H) reference target.

  20. Materials Challenges in Nuclear Energy

    SciTech Connect

    Zinkle, Steven J; Was, Gary

    2013-01-01

    Nuclear power currently provides about 13% of the worldwide electrical power, and has emerged as a reliable baseload source of electricity. A number of materials challenges must be successfully resolved for nuclear energy to continue to make further improvements in reliability, safety and economics. The operating environment for materials in current and proposed future nuclear energy systems is summarized, along with a description of materials used for the main operating components. Materials challenges associated with power uprates and extensions of the operating lifetimes of reactors are described. The three major materials challenges for the current and next generation of water-cooled fission reactors are centered on two structural materials aging degradation issues (corrosion and stress corrosion cracking of structural materials and neutron-induced embrittlement of reactor pressure vessels), along with improved fuel system reliability and accident tolerance issues. The major corrosion and stress corrosion cracking degradation mechanisms for light water reactors are reviewed. The materials degradation issues for the Zr alloy clad UO2 fuel system currently utilized in the majority of commercial nuclear power plants is discussed for normal and off-normal operating conditions. Looking to proposed future (Generation IV) fission and fusion energy systems, there are 5 key bulk radiation degradation effects (low temperature radiation hardening and embrittlement, radiation-induced and modified solute segregation and phase stability, irradiation creep, void swelling, and high temperature helium embrittlement) and a multitude of corrosion and stress corrosion cracking effects (including irradiation-assisted phenomena) that can have a major impact on the performance of structural materials.

  1. Relevant energy ranges for astrophysical reaction rates

    SciTech Connect

    Rauscher, Thomas

    2010-04-15

    Effective energy windows (Gamow windows) of astrophysical reaction rates for (p,gamma), (p,n), (p,alpha), (alpha,gamma), (alpha,n), (alpha,p), (n,gamma), (n,p), and (n,alpha) on targets with 10<=Z<=83 from proton to neutron dripline are calculated using theoretical cross sections. It is shown that widely used approximation formulas for the relevant energy ranges are not valid for a large number of reactions relevant to hydrostatic and explosive nucleosynthesis. The influence of the energy dependence of the averaged widths on the location of the Gamow windows is discussed and the results are presented in tabular form.

  2. Reaction wheels for kinetic energy storage

    NASA Technical Reports Server (NTRS)

    Studer, P. A.

    1984-01-01

    In contrast to all existing reaction wheel implementations, an order of magnitude increase in speed can be obtained efficiently if power to the actuators can be recovered. This allows a combined attitude control-energy storage system to be developed with structure mounted reaction wheels. The feasibility of combining reaction wheels with energy storage wwheels is demonstrated. The power required for control torques is a function of wheel speed but this energy is not dissipated; it is stored in the wheel. The I(2)R loss resulting from a given torque is shown to be constant, independent of the design speed of the motor. What remains, in order to efficiently use high speed wheels (essential for energy storage) for control purposes, is to reduce rotational losses to acceptable levels. Progress was made in permanent magnet motor design for high speed operation. Variable field motors offer more control flexibility and efficiency over a broader speed range.

  3. Unified ab initio approaches to nuclear structure and reactions

    NASA Astrophysics Data System (ADS)

    Navrátil, Petr; Quaglioni, Sofia; Hupin, Guillaume; Romero-Redondo, Carolina; Calci, Angelo

    2016-05-01

    The description of nuclei starting from the constituent nucleons and the realistic interactions among them has been a long-standing goal in nuclear physics. In addition to the complex nature of the nuclear forces, with two-, three- and possibly higher many-nucleon components, one faces the quantum-mechanical many-nucleon problem governed by an interplay between bound and continuum states. In recent years, significant progress has been made in ab initio nuclear structure and reaction calculations based on input from QCD-employing Hamiltonians constructed within chiral effective field theory. After a brief overview of the field, we focus on ab initio many-body approaches—built upon the no-core shell model—that are capable of simultaneously describing both bound and scattering nuclear states, and present results for resonances in light nuclei, reactions important for astrophysics and fusion research. In particular, we review recent calculations of resonances in the 6He halo nucleus, of five- and six-nucleon scattering, and an investigation of the role of chiral three-nucleon interactions in the structure of 9Be. Further, we discuss applications to the 7Be {({{p}},γ )}8{{B}} radiative capture. Finally, we highlight our efforts to describe transfer reactions including the 3H{({{d}},{{n}})}4He fusion.

  4. Spectroscopic study of sub-barrier quasi-elastic nuclear reactions

    SciTech Connect

    Pass, C.N.; Evans, P.M.; Smith, A.E.; Stuttge, L.; Betts, R.R.; Lilley, J.S.; Connell, K.A.; Simpson, J.; Smith, J.R.; James, A.N.

    1988-01-01

    The technique developed in this paper is particularly well suited to the detailed spectroscopic study of low energy quasi-elastic nuclear reactions and by overcoming the limitations of conventional procedure, the prospect of detailed studies of inclusive reaction mechanism may be realised. With only limited statistics we find evidence for strong multistep character in the transfer of a single nucleon from spherical vibrational target to spherical projectile nuclei. The suggestive measurements reported here may be made definitive through extended runs based on this technique and experiments planned for the future offer the real prospect of developing a quantified interpretation of the reaction process. 9 refs. 5 figs.

  5. Universal Nuclear Energy Density Functional

    SciTech Connect

    Carlson, Joseph; Furnstahl, Richard; Horoi, Mihai; Lusk, Rusty; Nazarewicz, Witold; Ng, Esmond; Thompson, Ian; Vary, James

    2012-12-01

    An understanding of the properties of atomic nuclei is crucial for a complete nuclear theory, for element formation, for properties of stars, and for present and future energy and defense applications. During the period of Dec. 1 2006 – Jun. 30, 2012, the UNEDF collaboration carried out a comprehensive study of all nuclei, based on the most accurate knowledge of the strong nuclear interaction, the most reliable theoretical approaches, the most advanced algorithms, and extensive computational resources, with a view towards scaling to the petaflop platforms and beyond. Until recently such an undertaking was hard to imagine, and even at the present time such an ambitious endeavor would be far beyond what a single researcher or a traditional research group could carry out.

  6. Method and apparatus for generating low energy nuclear particles

    DOEpatents

    Powell, James R.; Reich, Morris; Ludewig, Hans; Todosow, Michael

    1999-02-09

    A particle accelerator (12) generates an input particle beam having an initial energy level above a threshold for generating secondary nuclear particles. A thin target (14) is rotated in the path of the input beam for undergoing nuclear reactions to generate the secondary particles and correspondingly decrease energy of the input beam to about the threshold. The target (14) produces low energy secondary particles and is effectively cooled by radiation and conduction. A neutron scatterer (44) and a neutron filter (42) are also used for preferentially degrading the secondary particles into a lower energy range if desired.

  7. Method and apparatus for generating low energy nuclear particles

    DOEpatents

    Powell, J.R.; Reich, M.; Ludewig, H.; Todosow, M.

    1999-02-09

    A particle accelerator generates an input particle beam having an initial energy level above a threshold for generating secondary nuclear particles. A thin target is rotated in the path of the input beam for undergoing nuclear reactions to generate the secondary particles and correspondingly decrease energy of the input beam to about the threshold. The target produces low energy secondary particles and is effectively cooled by radiation and conduction. A neutron scatterer and a neutron filter are also used for preferentially degrading the secondary particles into a lower energy range if desired. 18 figs.

  8. Sparking fusion: A step toward laser-initiated nuclear fusion reactions

    SciTech Connect

    Peterson, I.

    1996-10-19

    The fusion furnace at the sun`s core burns hydrogen to make helium. Each time two hydrogen nuclei, or protons, merge to create a deuterium nucleus, the process releases energy. A chain of additional energy-producing nuclear reactions then converts deuterium into helium. Because protons, with their like electric charges, naturally repel each other, high temperatures and tremendous pressures are needed to force them together closely enough to initiate and sustain the reactions. These mergers cost energy initially, but the return on that investment proves prodigious. On Earth, such an energy payoff has been achieved only in the uncontrolled fury of a detonated hydrogen bomb. The vision of harnessing and controlling nuclear fusion as a terrestrial energy source has yet to be fulfilled. The proposed National Ignition Facility (NIF) represents an ambitious effort to use powerful lasers to deposit sufficient energy in a small capsule of nuclear fuel to trigger fusion. The main justification for the project is to ensure that a core group of physicists and engineers maintains its expertise in the physics of nuclear weapons. This article presents both the scientific and political sides of the NIF facility.

  9. Studies on Nuclear Astrophysics and Exotic Structure at the Low-Energy RI Beam Facility CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Kahl, D.; Hayakawa, S.; Sakaguchi, Y.; Nakao, T.; Wakabayashi, Y.; Hashimoto, T.; Teranishi, T.; Kubono, S.; Cherubini, S.; Mazzocco, M.; Signorini, C.; Gulino, M.; Di Pietro, A.; Figuera, P.; La Cognata, M.; Lattuada, M.; Spitaleri, C.; Torresi, D.; Lee, P. S.; Lee, C. S.; Komatsubara, T.; Iwasa, N.; Okoda, Y.; Pierroutsakou, D.; Parascandolo, C.; La Commara, M.; Strano, E.; Boiano, C.; Boiano, A.; Manea, C.; Sánchez-Benítez, A. M.; Miyatake, H.; Watanabe, Y. X.; Ishiyama, H.; Jeong, S. C.; Imai, N.; Hirayama, Y.; Kimura, S.; Mukai, M.; Kim, Y. H.; Lin, C. J.; Jia, H. M.; Yan, L.; Yang, Y. Y.; Kawabata, T.; Kwon, Y. K.; Binh, D. N.; Khiem, L. H.; Duy, N. N.

    Studies on nuclear astrophysics, resonant structure, and nuclear reaction are going on at CRIB (CNS Radioactive Ion Beam separator), a low-energy RI beam separator operated by Center for Nuclear Study (CNS), the University of Tokyo. Two major methods used at CRIB to study nuclear reactions of astrophysical relevance are the resonant scattering, and direct measurements of (α,p) reactions using a thick-gas target. Several experiments for decay measurements and reaction mechanism are also performed using low-energy RI beams at CRIB. Some of the results from recent experiments at CRIB are discussed.

  10. BUILDING A UNIVERSAL NUCLEAR ENERGY DENSITY FUNCTIONAL (UNEDF)

    SciTech Connect

    Nazarewicz, Witold

    2012-07-01

    The long-term vision initiated with UNEDF is to arrive at a comprehensive, quantitative, and unified description of nuclei and their reactions, grounded in the fundamental interactions between the constituent nucleons. We seek to replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that delivers maximum predictive power with well-quantified uncertainties. Specifically, the mission of this project has been three-fold: First, to find an optimal energy density functional (EDF) using all our knowledge of the nucleonic Hamiltonian and basic nuclear properties. Second, to apply the EDF theory and its extensions to validate the functional using all the available relevant nuclear structure and reaction data. Third, to apply the validated theory to properties of interest that cannot be measured, in particular the properties needed for reaction theory.

  11. Nuclear energy in Malaysia - closing the gaps

    NASA Astrophysics Data System (ADS)

    >Malaysian Nuclear Society (Mns,

    2013-06-01

    This article is prepared by the Malaysian Nuclear Society (MNS) to present the views of the Malaysian scientific community on the need for Malaysia to urgently upgrade its technical know-how and expertise to support the nuclear energy industry for future sustainable economic development of the country. It also present scientific views that nuclear energy will bring economic growth as well as technically sound industry, capable of supporting nuclear energy industry needs in the country, and recommend action items for timely technical upgrading of Malaysian expertise related to nuclear energy industry.

  12. Databases and tools for nuclear astrophysics applications. BRUSsels Nuclear LIBrary (BRUSLIB), Nuclear Astrophysics Compilation of REactions II (NACRE II) and Nuclear NETwork GENerator (NETGEN)

    NASA Astrophysics Data System (ADS)

    Xu, Y.; Goriely, S.; Jorissen, A.; Chen, G. L.; Arnould, M.

    2013-01-01

    An update of a previous description of the BRUSLIB + NACRE package of nuclear data for astrophysics and of the web-based nuclear network generator NETGEN is presented. The new version of BRUSLIB contains the latest predictions of a wide variety of nuclear data based on the most recent version of the Brussels-Montreal Skyrme-Hartree-Fock-Bogoliubov model. The nuclear masses, radii, spin/parities, deformations, single-particle schemes, matter densities, nuclear level densities, E1 strength functions, fission properties, and partition functions are provided for all nuclei lying between the proton and neutron drip lines over the 8 ≤ Z ≤ 110 range, whose evaluation is based on a unique microscopic model that ensures a good compromise between accuracy, reliability, and feasibility. In addition, these various ingredients are used to calculate about 100 000 Hauser-Feshbach neutron-, proton-, α-, and γ-induced reaction rates based on the reaction code TALYS. NACRE is superseded by the NACRE II compilation for 15 charged-particle transfer reactions and 19 charged-particle radiative captures on stable targets with mass numbers A < 16. NACRE II features the inclusion of experimental data made available after the publication of NACRE in 1999 and up to 2011. In addition, the extrapolation of the available data to the very low energies of astrophysical relevance is improved through the systematic use of phenomenological potential models. Uncertainties in the rates are also evaluated on this basis. Finally, the latest release v10.0 of the web-based tool NETGEN is presented. In addition to the data already used in the previous NETGEN package, it contains in a fully documented form the new BRUSLIB and NACRE II data, as well as new experiment-based radiative neutron capture cross sections. The full new versions of BRUSLIB, NACRE II, and NETGEN are available electronically from the nuclear database at http://www.astro.ulb.ac.be/NuclearData. The nuclear material is presented in

  13. Nuclear Powerplant Safety: Source Terms. Nuclear Energy.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC. Nuclear Energy Office.

    There has been increased public interest in the potential effects of nuclear powerplant accidents since the Soviet reactor accident at Chernobyl. People have begun to look for more information about the amount of radioactivity that might be released into the environment as a result of such an accident. When this issue is discussed by people…

  14. Time-dependent Green's functions approach to nuclear reactions

    SciTech Connect

    Rios, Arnau; Danielewicz, Pawel

    2008-04-04

    Nonequilibrium Green's functions represent underutilized means of studying evolution of quantum many-body systems. In view of a rising computer power, an effort is underway to apply the Green's functions to the dynamics of central nuclear reactions. As the first step, mean-field evolution for the density matrix for colliding slabs is studied in one dimension. Strategy to extend the dynamics to correlations is described.

  15. What can nuclear energy do for society.

    NASA Technical Reports Server (NTRS)

    Rom, F. E.

    1972-01-01

    It is pointed out that the earth's crust holds 30,000 times as much energy in the form of fissionable atoms as fossil fuel. Moreover, nuclear fuel costs less per unit of energy than fossil fuel. Capital equipment used to release nuclear energy, on the other hand, is expensive. For commercial electric-power production and marine propulsion, advantages of nuclear power have outweighed disadvantages. As to nuclear submarines, applications other than military may prove feasible. The industry has proposed cargo submarines to haul oil from the Alaskan North Slope beneath the Arctic ice. Other possible applications for nuclear power are in air-cushion-vehicles, aircraft, and rockets.-

  16. Computed potential energy surfaces for chemical reactions

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.; Levin, Eugene

    1993-01-01

    A new global potential energy surface (PES) is being generated for O(P-3) + H2 yields OH + H. This surface is being fit using the rotated Morse oscillator method, which was used to fit the previous POL-CI surface. The new surface is expected to be more accurate and also includes a much more complete sampling of bent geometries. A new study has been undertaken of the reaction N + O2 yields NO + O. The new studies have focused on the region of the surface near a possible minimum corresponding to the peroxy form of NOO. A large portion of the PES for this second reaction has been mapped out. Since state to state cross sections for the reaction are important in the chemistry of high temperature air, these studies will probably be extended to permit generation of a new global potential for reaction.

  17. Low Energy Ion-Molecule Reactions

    SciTech Connect

    James M. Farrar

    2004-05-01

    This objective of this project is to study the dynamics of the interactions of low energy ions important in combustion with small molecules in the gas phase and with liquid hydrocarbon surfaces. The first of these topics is a long-standing project in our laboratory devoted to probing the key features of potential energy surfaces that control chemical reactivity. The project provides detailed information on the utilization of specific forms of incident energy, the role of preferred reagent geometries, and the disposal of total reaction energy into product degrees of freedom. We employ crossed molecular beam methods under single collision conditions, at collision energies from below one eV to several eV, to probe potential surfaces over a broad range of distances and interaction energies. These studies allow us to test and validate dynamical models describing chemical reactivity. Measurements of energy and angular distributions of the reaction products with vibrational state resolution provide the key data for these studies. We employ the crossed beam low energy mass spectrometry methods that we have developed over the last several years.

  18. Assessment and requirements of nuclear reaction databases for GCR transport in the atmosphere and structures.

    PubMed

    Cucinotta, F A; Wilson, J W; Shinn, J L; Tripathi, R K

    1998-01-01

    The transport properties of galactic cosmic rays (GCR) in the atmosphere, material structures, and human body (self-shielding) are of interest in risk assessment for supersonic and subsonic aircraft and for space travel in low-Earth orbit and on interplanetary missions. Nuclear reactions, such as knockout and fragmentation, present large modifications of particle type and energies of the galactic cosmic rays in penetrating materials. We make an assessment of the current nuclear reaction models and improvements in these model for developing required transport code data bases. A new fragmentation data base (QMSFRG) based on microscopic models is compared to the NUCFRG2 model and implications for shield assessment made using the HZETRN radiation transport code. For deep penetration problems, the build-up of light particles, such as nucleons, light clusters and mesons from nuclear reactions in conjunction with the absorption of the heavy ions, leads to the dominance of the charge Z = 0, 1, and 2 hadrons in the exposures at large penetration depths. Light particles are produced through nuclear or cluster knockout and in evaporation events with characteristically distinct spectra which play unique roles in the build-up of secondary radiation's in shielding. We describe models of light particle production in nucleon and heavy ion induced reactions and make an assessment of the importance of light particle multiplicity and spectral parameters in these exposures.

  19. Assessment and Requirements of Nuclear Reaction Databases for GCR Transport in the Atmosphere and Structures

    NASA Technical Reports Server (NTRS)

    Cucinotta, F. A.; Wilson, J. W.; Shinn, J. L.; Tripathi, R. K.

    1998-01-01

    The transport properties of galactic cosmic rays (GCR) in the atmosphere, material structures, and human body (self-shielding) am of interest in risk assessment for supersonic and subsonic aircraft and for space travel in low-Earth orbit and on interplanetary missions. Nuclear reactions, such as knockout and fragmentation, present large modifications of particle type and energies of the galactic cosmic rays in penetrating materials. We make an assessment of the current nuclear reaction models and improvements in these model for developing required transport code data bases. A new fragmentation data base (QMSFRG) based on microscopic models is compared to the NUCFRG2 model and implications for shield assessment made using the HZETRN radiation transport code. For deep penetration problems, the build-up of light particles, such as nucleons, light clusters and mesons from nuclear reactions in conjunction with the absorption of the heavy ions, leads to the dominance of the charge Z = 0, 1, and 2 hadrons in the exposures at large penetration depths. Light particles are produced through nuclear or cluster knockout and in evaporation events with characteristically distinct spectra which play unique roles in the build-up of secondary radiation's in shielding. We describe models of light particle production in nucleon and heavy ion induced reactions and make an assessment of the importance of light particle multiplicity and spectral parameters in these exposures.

  20. Nuclear structure studies with intermediate energy probes

    SciTech Connect

    Lee, T.S.H.

    1993-10-01

    Nuclear structure studies with pions are reviewed. Results from a recent study of 1 p-shell nuclei using (e,e{prime}), ({pi}, {pi}{prime}), and ({gamma},{pi}) reactions are reported. Future nuclear structure studies with GeV electrons at CEBAF are also briefly discussed.

  1. VizieR Online Data Catalog: Brussels nuclear reaction rate library (Aikawa+, 2005)

    NASA Astrophysics Data System (ADS)

    Aikawa, M.; Arnould, M.; Goriely, S.; Jorissen, A.; Takahashi, K.

    2005-07-01

    The present data is part of the Brussels nuclear reaction rate library (BRUSLIB) for astrophysics applications and concerns nuclear reaction rate predictions calculated within the statistical Hauser-Feshbach approximation and making use of global and coherent microscopic nuclear models for the quantities (nuclear masses, nuclear structure properties, nuclear level densities, gamma-ray strength functions, optical potentials) entering the rate calculations. (4 data files).

  2. Investigating resonances above and below the threshold in nuclear reactions of astrophysical interest and beyond

    SciTech Connect

    La Cognata, M.; Kiss, G. G.; Mukhamedzhanov, A. M.; Spitaleri, C.; Trippella, O.

    2015-10-15

    Resonances in nuclear cross sections dramatically change their trends. Therefore, the presence of unexpected resonances might lead to unpredicted consequences on astrophysics and nuclear physics. In nuclear physics, resonances allow one to study states in the intermediate compound systems, to evaluate their cluster structure, for instance, especially in the energy regions approaching particle decay thresholds. In astrophysics, resonances might lead to changes in the nucleosynthesis flow, determining different isotopic compositions of the nuclear burning ashes. For these reasons, the Trojan Horse method has been modified to investigate resonant reactions. Thanks to this novel approach, for the first time normalization to direct data might be avoided. Moreover, in the case of sub threshold resonances, the Trojan Horse method modified to investigate resonances allows one to deduce the asymptotic normalization coefficient, showing the close connection between the two indirect approaches.

  3. Investigating resonances above and below the threshold in nuclear reactions of astrophysical interest and beyond

    NASA Astrophysics Data System (ADS)

    La Cognata, M.; Kiss, G. G.; Mukhamedzhanov, A. M.; Spitaleri, C.; Trippella, O.

    2015-10-01

    Resonances in nuclear cross sections dramatically change their trends. Therefore, the presence of unexpected resonances might lead to unpredicted consequences on astrophysics and nuclear physics. In nuclear physics, resonances allow one to study states in the intermediate compound systems, to evaluate their cluster structure, for instance, especially in the energy regions approaching particle decay thresholds. In astrophysics, resonances might lead to changes in the nucleosynthesis flow, determining different isotopic compositions of the nuclear burning ashes. For these reasons, the Trojan Horse method has been modified to investigate resonant reactions. Thanks to this novel approach, for the first time normalization to direct data might be avoided. Moreover, in the case of sub threshold resonances, the Trojan Horse method modified to investigate resonances allows one to deduce the asymptotic normalization coefficient, showing the close connection between the two indirect approaches.

  4. Nuclear Energy for Water Desalting, A Bibliography.

    ERIC Educational Resources Information Center

    Kuhns, Helen F., Comp.; And Others

    This bibliography includes 215 abstracts of publications on the use of nuclear energy in the production of potable water from saline or brackish waters. The uses of nuclear reactors, radioisotopic heat sources, and nuclear explosives are covered in relation to the various desalination methods available. Literature through April 1967 has been…

  5. Minimum Energy Pathways for Chemical Reactions

    NASA Technical Reports Server (NTRS)

    Walch, S. P.; Langhoff, S. R. (Technical Monitor)

    1995-01-01

    Computed potential energy surfaces are often required for computation of such parameters as rate constants as a function of temperature, product branching ratios, and other detailed properties. We have found that computation of the stationary points/reaction pathways using CASSCF/derivative methods, followed by use of the internally contracted CI method to obtain accurate energetics, gives useful results for a number of chemically important systems. The talk will focus on a number of applications to reactions leading to NOx and soot formation in hydrocarbon combustion.

  6. Hadronic nuclear energy: An approach towards green energy

    SciTech Connect

    Das Sarma, Indrani B.

    2015-03-10

    Nuclear energy is undoubtedly the largest energy source capable of meeting the total energy requirements to a large extent in long terms. However the conventional nuclear energy involves production of high level of radioactive wastes which possesses threat, both to the environment and mankind. The modern day demand of clean, cheap and abundant energy gets fulfilled by the novel fuels that have been developed through hadronic mechanics/chemistry. In the present paper, a short review of Hadronic nuclear energy by intermediate controlled nuclear synthesis and particle type like stimulated neutron decay and double beta decay has been presented.

  7. Nuclear structure at intermediate energies

    SciTech Connect

    Bonner, B.E.; Mutchler, G.S.

    1991-09-30

    The theme that unites the sometimes seemingly disparate experiments undertaken by the Bonner Lab Medium Energy Group is a determination to understand in detail the many facets and manifestations of the strong interaction, that which is now referred to as nonperturbative QCD. Whether we are investigating the question of just what does carry the spin of baryons, or the extent of the validity of the SU(6) wavefunctions for the excited hyperons (as will be measured in their radiative decays in our CEBAF experiment), or questions associated with the formation of a new state of matter predicted by QCD (the subject of our BNL experiments E810, E854, as well as our approved experiment at RHIC), -- all these projects share this common goal. Our other experiments represent different approaches to the same broad undertaking. LAMPF E1097 will provide definitive answers to the question of the spin dependence of the inelastic channel of pion production in the n-p interaction. FNAL E683 may well open a new field of investigation in nuclear physics: that of just how quarks and gluons interact with nuclear matter as they transverse nuclei of different sizes. In most all of the experiments mentioned above, the Bonner Lab Group is playing major leadership roles as well as doing a big fraction of the hard work that such experiments require. We use many of the facilities that are unavailable to the intermediate energy physics community and we use our expertise to design and fabricate the detectors and instrumentation that are required to perform the measurements which we decide to do.

  8. Renewability and sustainability aspects of nuclear energy

    SciTech Connect

    Şahin, Sümer

    2014-09-30

    Renewability and sustainability aspects of nuclear energy have been presented on the basis of two different technologies: (1) Conventional nuclear technology; CANDU reactors. (2) Emerging nuclear technology; fusion/fission (hybrid) reactors. Reactor grade (RG) plutonium, {sup 233}U fuels and heavy water moderator have given a good combination with respect to neutron economy so that mixed fuel made of (ThO{sub 2}/RG‐PuO{sub 2}) or (ThC/RG-PuC) has lead to very high burn up grades. Five different mixed fuel have been selected for CANDU reactors composed of 4 % RG‐PuO{sub 2} + 96 % ThO{sub 2}; 6 % RG‐PuO{sub 2} + 94 % ThO{sub 2}; 10 % RG‐PuO{sub 2} + 90 % ThO{sub 2}; 20 % RG‐PuO{sub 2} + 80 % ThO{sub 2}; 30 % RG‐PuO{sub 2} + 70 % ThO{sub 2}, uniformly taken in each fuel rod in a fuel channel. Corresponding operation lifetimes have been found as ∼ 0.65, 1.1, 1.9, 3.5, and 4.8 years and with burn ups of ∼ 30 000, 60 000, 100 000, 200 000 and 290 000 MW.d/ton, respectively. Increase of RG‐PuO{sub 2} fraction in radial direction for the purpose of power flattening in the CANDU fuel bundle has driven the burn up grade to 580 000 MW.d/ton level. A laser fusion driver power of 500 MW{sub th} has been investigated to burn the minor actinides (MA) out of the nuclear waste of LWRs. MA have been homogenously dispersed as carbide fuel in form of TRISO particles with volume fractions of 0, 2, 3, 4 and 5 % in the Flibe coolant zone in the blanket surrounding the fusion chamber. Tritium breeding for a continuous operation of the fusion reactor is calculated as TBR = 1.134, 1.286, 1.387, 1.52 and 1.67, respectively. Fission reactions in the MA fuel under high energetic fusion neutrons have lead to the multiplication of the fusion energy by a factor of M = 3.3, 4.6, 6.15 and 8.1 with 2, 3, 4 and 5 % TRISO volume fraction at start up, respectively. Alternatively with thorium, the same fusion driver would produce ∼160 kg {sup 233}U per year in addition to fission

  9. Renewability and sustainability aspects of nuclear energy

    NASA Astrophysics Data System (ADS)

    Şahin, Sümer

    2014-09-01

    Renewability and sustainability aspects of nuclear energy have been presented on the basis of two different technologies: (1) Conventional nuclear technology; CANDU reactors. (2) Emerging nuclear technology; fusion/fission (hybrid) reactors. Reactor grade (RG) plutonium, 233U fuels and heavy water moderator have given a good combination with respect to neutron economy so that mixed fuel made of (ThO2/RG-PuO2) or (ThC/RG-PuC) has lead to very high burn up grades. Five different mixed fuel have been selected for CANDU reactors composed of 4 % RG-PuO2 + 96 % ThO2; 6 % RG-PuO2 + 94 % ThO2; 10 % RG-PuO2 + 90 % ThO2; 20 % RG-PuO2 + 80 % ThO2; 30 % RG-PuO2 + 70 % ThO2, uniformly taken in each fuel rod in a fuel channel. Corresponding operation lifetimes have been found as ˜ 0.65, 1.1, 1.9, 3.5, and 4.8 years and with burn ups of ˜ 30 000, 60 000, 100 000, 200 000 and 290 000 MW.d/ton, respectively. Increase of RG-PuO2 fraction in radial direction for the purpose of power flattening in the CANDU fuel bundle has driven the burn up grade to 580 000 MW.d/ton level. A laser fusion driver power of 500 MWth has been investigated to burn the minor actinides (MA) out of the nuclear waste of LWRs. MA have been homogenously dispersed as carbide fuel in form of TRISO particles with volume fractions of 0, 2, 3, 4 and 5 % in the Flibe coolant zone in the blanket surrounding the fusion chamber. Tritium breeding for a continuous operation of the fusion reactor is calculated as TBR = 1.134, 1.286, 1.387, 1.52 and 1.67, respectively. Fission reactions in the MA fuel under high energetic fusion neutrons have lead to the multiplication of the fusion energy by a factor of M = 3.3, 4.6, 6.15 and 8.1 with 2, 3, 4 and 5 % TRISO volume fraction at start up, respectively. Alternatively with thorium, the same fusion driver would produce ˜160 kg 233U per year in addition to fission energy production in situ, multiplying the fusion energy by a factor of ˜1.3.

  10. EXFOR systems manual: Nuclear reaction data exchange format

    SciTech Connect

    McLane, V.

    1996-07-01

    This document describes EXFOR, the exchange format designed to allow transmission of nuclear reaction data between the members of the Nuclear Data Centers Network. In addition to storing the data and its bibliographic information, experimental information, including source of uncertainties, is also compiled. The status and history of the data set is also included, e.g., the source of the data, any updates which have been made, and correlations to other data sets. The exchange format, as outlined, is designed to allow a large variety of numerical data tables with explanatory and bibliographic information to be transmitted in an easily machine-readable format (for checking and indicating possible errors) and a format that can be read by personnel (for passing judgment on and correcting any errors indicated by the machine).

  11. Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter

    SciTech Connect

    Voinov, A. V.; Grimes, S. M.; Brune, C. R.; Burger, A.; Gorgen, A.; Guttormsen, M.; Larsen, A. C.; Massey, T. N.; Siem, S.

    2014-09-03

    Here, the proton spectrum from the 57Fe(α,p) reaction has been measured and analyzed with the Hauser-Feshbach model of nuclear reactions. Different input level density models have been tested. It was found that the best description is achieved with either Fermi-gas or constant temperature model functions obtained by fitting them to neutron resonance spacing and to discrete levels and using the spin cutoff parameter with much weaker excitation energy dependence than it is predicted by the Fermi-gas model.

  12. Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter

    DOE PAGES

    Voinov, A. V.; Grimes, S. M.; Brune, C. R.; Burger, A.; Gorgen, A.; Guttormsen, M.; Larsen, A. C.; Massey, T. N.; Siem, S.

    2014-09-03

    Here, the proton spectrum from the 57Fe(α,p) reaction has been measured and analyzed with the Hauser-Feshbach model of nuclear reactions. Different input level density models have been tested. It was found that the best description is achieved with either Fermi-gas or constant temperature model functions obtained by fitting them to neutron resonance spacing and to discrete levels and using the spin cutoff parameter with much weaker excitation energy dependence than it is predicted by the Fermi-gas model.

  13. Interplay between compound and fragments aspects of nuclear fission and heavy-ion reaction

    SciTech Connect

    Moller, Peter; Iwamoto, A; Ichikawa, I

    2010-09-10

    The scission point in nuclear fission plays a special role where one-body system changes to two-body system. Inverse of this situation is realized in heavy-ion fusion reaction where two-body system changes to one body system. Among several peculiar phenomena expected to occur during this change, we focus our attention to the behavior of compound and fragments shell effects. Some aspects of the interplay between compound and fragments shell effect are discussed related to the topics of the fission valleys in the potential energy surface of actinide nuclei and the fusion-like trajectory found in the cold fusion reaction leading to superheavy nuclei.

  14. Hydrogen release from irradiated elastomers measured by Nuclear Reaction Analysis

    NASA Astrophysics Data System (ADS)

    Jagielski, J.; Ostaszewska, U.; Bielinski, D. M.; Grambole, D.; Romaniec, M.; Jozwik, I.; Kozinski, R.; Kosinska, A.

    2016-03-01

    Ion irradiation appears as an interesting method of modification of elastomers, especially friction and wear properties. Main structural effect caused by heavy ions is a massive loss of hydrogen from the surface layer leading to its smoothening and shrinking. The paper presents the results of hydrogen release from various elastomers upon irradiation with H+, He+ and Ar+ studied by using Nuclear Reaction Analysis (NRA) method. The analysis of the experimental data indicates that the hydrogen release is controlled by inelastic collisions between ions and target electrons. The last part of the study was focused on preliminary analysis of mechanical properties of irradiated rubbers.

  15. Initiation of nuclear reactions in femtosecond laser plasma

    SciTech Connect

    Golovinski, P. A.; Mikhin, E. A.

    2013-01-15

    Mechanisms of electron interaction with a nucleus via a direct electron-nucleus collision and via bremsstrahlung generated in electron scattering on a nucleus in a femtosecond laser plasma are considered. The description of this interaction is simplified substantially by using the instantaneous-impact and equivalent-photon approximations. The yields of photons, electron-positron pairs, and products of nuclear reactions initiated by a laser pulse for some nuclei are calculated. In particular, this is done for {sup 235}U, {sup 236}U, {sup 238}U, and {sup 232}Th fission in a laser field of intensity 10{sup 20} to 10{sup 22} W/cm{sup 2}.

  16. Advanced scheme for high-yield laser driven nuclear reactions

    NASA Astrophysics Data System (ADS)

    Margarone, D.; Picciotto, A.; Velyhan, A.; Krasa, J.; Kucharik, M.; Mangione, A.; Szydlowsky, A.; Malinowska, A.; Bertuccio, G.; Shi, Y.; Crivellari, M.; Ullschmied, J.; Bellutti, P.; Korn, G.

    2015-01-01

    The use of a low contrast nanosecond laser pulse with a relatively low intensity (3  ×  1016 W cm-2) allowed the enhancing of the yield of induced nuclear reactions in advanced solid targets. In particular the ‘ultraclean’ proton-boron fusion reaction, producing energetic alpha particles without neutron generation, was chosen. A spatially well-defined layer of boron dopants in a hydrogen-enriched silicon substrate was used as a target. A combination of the specific target composition and the laser pulse temporal shape allowed the enhancing of the yield of alpha particles up to 109 per steradian. This result can be ascribed to the interaction of the long-laser pre-pulse with the target and to the optimal target geometry and composition.

  17. A Nuclear Reaction Analysis study of fluorine uptake in flint

    SciTech Connect

    Jin, Jian-Yue; Weathers, D. L.; Picton, F.; Hughes, B. F.; Duggan, J. L.; McDaniel, F. D.; Matteson, S.

    1999-06-10

    Nuclear Reaction Analysis (NRA) using the {sup 19}F(p,{alpha}{gamma}){sup 16}O resonance reaction is a powerful method of fluorine depth profiling. We have used this method to study the fluorine uptake phenomenon in mineral flint, which could potentially develop into a method of dating archeological flint artifacts. Flint samples cut with a rock saw were immersed in aqueous fluoride solutions for different times for the uptake study. The results suggest that fluorine uptake is not a simple phenomenon, but rather a combination of several simultaneous processes. Fluorine surface adsorption appears to play an important role in developing the fluorine profiles. The surface adsorption was affected by several parameters such as pH value and fluorine concentration in the solution, among others. The problem of surface charging for the insulator materials during ion bombardment is also reported.

  18. EXTENSION OF THE NUCLEAR REACTION MODEL CODE EMPIRE TO ACTINIDES NUCLEAR DATA EVALUATION.

    SciTech Connect

    CAPOTE,R.; SIN, M.; TRKOV, A.; HERMAN, M.; CARLSON, B.V.; OBLOZINSKY, P.

    2007-04-22

    Recent extensions and improvements of the EMPIRE code system are outlined. They add new capabilities to the code, such as prompt fission neutron spectra calculations using Hauser-Feshbach plus pre-equilibrium pre-fission spectra, cross section covariance matrix calculations by Monte Carlo method, fitting of optical model parameters, extended set of optical model potentials including new dispersive coupled channel potentials, parity-dependent level densities and transmission through numerically defined fission barriers. These features, along with improved and validated ENDF formatting, exclusive/inclusive spectra, and recoils make the current EMPIRE release a complete and well validated tool for evaluation of nuclear data at incident energies above the resonance region. The current EMPIRE release has been used in evaluations of neutron induced reaction files for {sup 232}Th and {sup 231,233}Pa nuclei in the fast neutron region at IAEA. Triple-humped fission barriers and exclusive pre-fission neutron spectra were considered for the fission data evaluation. Total, fission, capture and neutron emission cross section, average resonance parameters and angular distributions of neutron scattering are in excellent agreement with the available experimental data.

  19. [Reaction mechanism studies of heavy ion induced nuclear reactions]. Annual progress report, [January 1992--February 1993

    SciTech Connect

    Mignerey, A.C.

    1993-02-01

    Completed work is summarized on the topics of excitation energy division in deep-inelastic reactions and the onset of multifragmentation in La-induced reactions at E/A = 45 MeV. Magnetic fields are being calculated for the PHOBOS detector system, a two-arm multiparticle spectrometer for studying low-transverse-momentum particles produced at the Relativistic Heavy Ion Collider. The Maryland Forward Array is being developed for detection of the reaction products from very peripheral collisions; it consists of two individual units of detectors: the annular silicon detector in front and the plastic phoswich detector at back.

  20. Nuclear Energy Assessment Battery. Form C.

    ERIC Educational Resources Information Center

    Showers, Dennis Edward

    This publication consists of a nuclear energy assessment battery for secondary level students. The test contains 44 multiple choice items and is organized into four major sections. Parts include: (1) a knowledge scale; (2) attitudes toward nuclear energy; (3) a behaviors and intentions scale; and (4) an anxiety scale. Directions are provided for…

  1. Designing the Nuclear Energy Attitude Scale.

    ERIC Educational Resources Information Center

    Calhoun, Lawrence; And Others

    1988-01-01

    Presents a refined method for designing a valid and reliable Likert-type scale to test attitudes toward the generation of electricity from nuclear energy. Discusses various tests of validity that were used on the nuclear energy scale. Reports results of administration and concludes that the test is both reliable and valid. (CW)

  2. A theological view of nuclear energy

    SciTech Connect

    Pollard, W.G.

    1982-07-01

    The author presents a theological perspective on nuclear power based on Israel's history, as revealed in the Hebrew Bible and the Alexandrian Greek Septuagint. Nuclear energy is described as God's energy choice for the whole of creation, which can be made as safe as traditional sources.

  3. The Trojan Horse method for nuclear astrophysics: Recent results on resonance reactions

    SciTech Connect

    Cognata, M. La; Pizzone, R. G.; Spitaleri, C.; Cherubini, S.; Romano, S.; Gulino, M.; Tumino, A.; Lamia, L.

    2014-05-09

    Nuclear astrophysics aims to measure nuclear-reaction cross sections of astrophysical interest to be included into models to study stellar evolution and nucleosynthesis. Low energies, < 1 MeV or even < 10 keV, are requested for this is the window where these processes are more effective. Two effects have prevented to achieve a satisfactory knowledge of the relevant nuclear processes, namely, the Coulomb barrier exponentially suppressing the cross section and the presence of atomic electrons. These difficulties have triggered theoretical and experimental investigations to extend our knowledge down to astrophysical energies. For instance, indirect techniques such as the Trojan Horse Method have been devised yielding new cutting-edge results. In particular, I will focus on the application of this indirect method to resonance reactions. Resonances might dramatically enhance the astrophysical S(E)-factor so, when they occur right at astrophysical energies, their measurement is crucial to pin down the astrophysical scenario. Unknown or unpredicted resonances might introduce large systematic errors in nucleosynthesis models. These considerations apply to low-energy resonances and to sub-threshold resonances as well, as they may produce sizable modifications of the S-factor due to, for instance, destructive interference with another resonance.

  4. Ab Initio Nuclear Structure and Reaction Calculations for Rare Isotopes

    SciTech Connect

    Draayer, Jerry P.

    2014-09-28

    We have developed a novel ab initio symmetry-adapted no-core shell model (SA-NCSM), which has opened the intermediate-mass region for ab initio investigations, thereby providing an opportunity for first-principle symmetry-guided applications to nuclear structure and reactions for nuclear isotopes from the lightest p-shell systems to intermediate-mass nuclei. This includes short-lived proton-rich nuclei on the path of X-ray burst nucleosynthesis and rare neutron-rich isotopes to be produced by the Facility for Rare Isotope Beams (FRIB). We have provided ab initio descriptions of high accuracy for low-lying (including collectivity-driven) states of isotopes of Li, He, Be, C, O, Ne, Mg, Al, and Si, and studied related strong- and weak-interaction driven reactions that are important, in astrophysics, for further understanding stellar evolution, X-ray bursts and triggering of s, p, and rp processes, and in applied physics, for electron and neutrino-nucleus scattering experiments as well as for fusion ignition at the National Ignition Facility (NIF).

  5. New exclusive CHIPS-TPT algorithms for simulation of neutron-nuclear reactions

    NASA Astrophysics Data System (ADS)

    Kosov, M.; Savin, D.

    2015-05-01

    The CHIPS-TPT physics library for simulation of neutron-nuclear reactions on the new exclusive level is being developed in CFAR VNIIA. The exclusive modeling conserves energy, momentum and quantum numbers in each neutron-nuclear interaction. The CHIPS-TPT algorithms are based on the exclusive CHIPS library, which is compatible with Geant4. Special CHIPS-TPT physics lists in the Geant4 format are provided. The calculation time for an exclusive CHIPS-TPT simulation is comparable to the time of the corresponding Geant4- HP simulation. In addition to the reduction of the deposited energy fluctuations, which is a consequence of the energy conservation, the CHIPS-TPT libraries provide a possibility of simulation of the secondary particles correlation, e.g. secondary gammas, and of the Doppler broadening of gamma lines in the spectrum, which can be measured by germanium detectors.

  6. On microscopic theory of radiative nuclear reaction characteristics

    NASA Astrophysics Data System (ADS)

    Kamerdzhiev, S. P.; Achakovskiy, O. I.; Avdeenkov, A. V.; Goriely, S.

    2016-07-01

    A survey of some results in the modern microscopic theory of properties of nuclear reactions with gamma rays is given. First of all, we discuss the impact of Phonon Coupling (PC) on the Photon Strength Function (PSF) because it represents the most natural physical source of additional strength found for Sn isotopes in recent experiments that could not be explained within the standard HFB + QRPA approach. The self-consistent version of the Extended Theory of Finite Fermi Systems in the Quasiparticle Time Blocking Approximation is applied. It uses the HFB mean field and includes both the QRPA and PC effects on the basis of the SLy4 Skyrme force. With our microscopic E1 PSFs, the following properties have been calculated for many stable and unstable even-even semi-magic Sn and Ni isotopes as well as for double-magic 132Sn and 208Pb using the reaction codes EMPIRE and TALYS with several Nuclear Level Density (NLD) models: (1) the neutron capture cross sections; (2) the corresponding neutron capture gamma spectra; (3) the average radiative widths of neutron resonances. In all the properties considered, the PC contribution turned out to be significant, as compared with the standard QRPA one, and necessary to explain the available experimental data. The results with the phenomenological so-called generalized superfluid NLD model turned out to be worse, on the whole, than those obtained with the microscopic HFB + combinatorial NLD model. The very topical question about the M1 resonance contribution to PSFs is also discussed. Finally, we also discuss the modern microscopic NLD models based on the self-consistent HFB method and show their relevance to explain the experimental data as compared with the phenomenological models. The use of these self-consistent microscopic approaches is of particular relevance for nuclear astrophysics, but also for the study of double-magic nuclei.

  7. Building A Universal Nuclear Energy Density Functional (UNEDF)

    SciTech Connect

    Joe Carlson; Dick Furnstahl; Mihai Horoi; Rusty Lusk; Witek Nazarewicz; Esmond Ng; Ian Thompson; James Vary

    2012-09-30

    During the period of Dec. 1 2006 - Jun. 30, 2012, the UNEDF collaboration carried out a comprehensive study of all nuclei, based on the most accurate knowledge of the strong nuclear interaction, the most reliable theoretical approaches, the most advanced algorithms, and extensive computational resources, with a view towards scaling to the petaflop platforms and beyond. The long-term vision initiated with UNEDF is to arrive at a comprehensive, quantitative, and unified description of nuclei and their reactions, grounded in the fundamental interactions between the constituent nucleons. We seek to replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that delivers maximum predictive power with well-quantified uncertainties. Specifically, the mission of this project has been three-fold: first, to find an optimal energy density functional (EDF) using all our knowledge of the nucleonic Hamiltonian and basic nuclear properties; second, to apply the EDF theory and its extensions to validate the functional using all the available relevant nuclear structure and reaction data; third, to apply the validated theory to properties of interest that cannot be measured, in particular the properties needed for reaction theory. The main physics areas of UNEDF, defined at the beginning of the project, were: ab initio structure; ab initio functionals; DFT applications; DFT extensions; reactions.

  8. Capture process in nuclear reactions with a quantum master equation

    SciTech Connect

    Sargsyan, V. V.; Kanokov, Z.; Adamian, G. G.; Antonenko, N. V.; Scheid, W.

    2009-09-15

    Projectile-nucleus capture by a target nucleus at bombarding energies in the vicinity of the Coulomb barrier is treated with the reduced-density-matrix formalism. The effects of dissipation and fluctuations on the capture process are taken self-consistently into account within the quantum model suggested. The excitation functions for the capture in the reactions {sup 16}O, {sup 19}F, {sup 26}Mg, {sup 28}Si, {sup 32,34,36,38}S, {sup 40,48}Ca, {sup 50}Ti, {sup 52}Cr+{sup 208}Pb with spherical nuclei are calculated and compared with the experimental data. At bombarding energies about (15-25) MeV above the Coulomb barrier the maximum of capture cross section is revealed for the {sup 58}Ni+{sup 208}Pb reaction.

  9. Breakup locations: Intertwining effects of nuclear structure and reaction dynamics

    NASA Astrophysics Data System (ADS)

    Dasgupta, M.; Simpson, E. C.; Luong, D. H.; Kalkal, Sunil; Cook, K. J.; Carter, I. P.; Hinde, D. J.; Williams, E.

    2016-05-01

    Studies at the Australian National University aim to distinguish breakup of the projectile like-nucleus that occurs when approaching the target from that when receding from the target. Helped by breakup simulations, observables have been found that are sensitive to the breakup location, and thus to the mean-lives of unbound states; sensitivity to even sub-zeptosecond lifetime is found. These results provide insights to understand the reaction dynamics of weakly bound nuclei at near barrier energies.

  10. Density dependence of nuclear symmetry energy

    NASA Astrophysics Data System (ADS)

    Behera, B.; Routray, T. R.; Tripathy, S. K.

    2016-10-01

    High density behavior of nuclear symmetry energy is studied on the basis of the stiffest density dependence of asymmetric contribution to energy per nucleon in charge neutral n + p + e + μ matter under beta equilibrium. The density dependence of nuclear symmetry energy obtained in this way is neither very stiff nor soft at high densities and is found to be in conformity with recent observations of neutron stars.

  11. Chemical composition and structure of particles synthesized on the surface of HHPC in nuclear reactions induced by bremstrahlung γ quanta with threshold energy of 10 MeV in molecular hydrogen at a pressure of 0.5 kbar

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wiśniewski, R.

    2015-12-01

    A high-pressure chamber filled with molecular hydrogen (HHPC) at a pressure of 0.5 kbar with a Pd rod inside has been irradiated for 14 h with γ quanta with an energy of 9.7 kbar produced by an electron beam current of 20-21 μA. Postirradiation studies of the changes in the structure of the synthesized particle and other objects on the surface of a brass hub in the composition of HHPC revealed the presence of light elements from carbon to calcium. Multiple small particles of lead have also been found and studied. The detected synthesized particle has complex shape and composition. Also, thin-walled microtubes were detected on the inner surfaces inside HHPC. Based on fission reactions of intermediate mass nuclei (descending reactions), as well as the reactions of synthesis from hydrogen and heavier nuclei (ascending reactions), an attempt to explain the anomalies that were observed is made.

  12. Generation IV nuclear energy systems and the need of accurate nuclear data

    NASA Astrophysics Data System (ADS)

    Colonna, N.

    2009-05-01

    To satisfy the world's demand of energy, constantly increasing over the years, a suitable mix of different energy sources has to be envisaged. In this scenario, an important role may be played by nuclear energy, provided that major safety, waste and proliferation issues affecting current nuclear reactors are satisfactorily addressed. In this respect, a large effort is under way since a few years towards the development of advanced nuclear systems that would use more efficiently the uranium resources, and produce a minimal amount of long-lived nuclear waste. The main activity concerns Generation IV reactors, with full or partial waste recycling capability. Their design requires R&D in numerous fields. Among the different needs, it is of fundamental importance to improve the knowledge of basic nuclear data, such as cross-sections for neutron-induced reactions on actinides. The main characteristics and principle of operation of the new generation nuclear systems are here described, together with the related needs of new and accurate nuclear data. Finally, an example of activity currently undergoing in the field is shown, with the recent experimental results obtained at the neutron facility n_TOF at CERN.

  13. Medium energy nuclear physics research

    NASA Astrophysics Data System (ADS)

    Peterson, G. A.; Dubach, J. F.; Hicks, R. S.; Miskimen, R. A.

    1991-06-01

    Research on the following topics is discussed: Transverse from factors of (Sn-117); Elastic magnetic electron scattering from C-13 at Q(exp 2) = 1 GeV(exp 2)/sq c; A reanalysis of C-13 elastic scattering; Deuteron threshold electrodisintegration; Measurement of the elastic magnetic form factor of He-3 at high momentum transfer; Coincidence measurement of the D(electron, electron proton) cross section at low excitation energy and high momentum transfer; Measurement of the quadrupole contribution to the N yields Delta excitation; measurement of the x-, Q(exp 2)-, and A-dependence of R = sigma sub L/sigma sub T; The PEGASYS project; PEP beam-gas event analysis; Plans for other experiments at SLAC, i.e., polarized electron scattering on polarized nuclei; Experiment PR-89-015 (study of coincidence reactions in the dip and delta resonance regions); Experiment PR-89-031 (multi-nulceon knockout using the CLAS detector); Drift chamber tests; A memorandum of understanding and test experiments; Photoprotons from (exp 10)B; And hadronic electroproduction at LEP.

  14. Medium energy nuclear physics research

    SciTech Connect

    Peterson, G.A.; Dubach, J.F.; Hicks, R.S.; Miskimen, R.A.

    1992-06-01

    This paper covers the following topics: Experiment 87-02: Threshold Electrodisintegration of the Deuteron at High Q{sup 2}; Measurement of the 5th Structure Function in Deuterium and {sup 12}C; Single-Particle Densities of sd-Shell Nuclei; Experiment 84-28: Transverse Form Factors of {sup 117}Sn; Experiment 82-11: Elastic Magnetic Electron Scattering from {sup 13}C; Experiment 89-09: Measurement of the Elastic Magnetic Form Factor of {sup 3}He at High Momentum Transfer; Experiment 89-15: Coincidence Measurement of the D(e,e{prime}p) Cross-Section at Low Excitation Energy and High Momentum Transfer; Experiment 87-09: Measurement of the Quadrupole Contribution to the N {yields} {Delta} Excitation; Experiment E-140: Measurement of the x-, Q{sup 2} and A-Dependence of R = {sigma}{sub L}/{sigma}{sub T}; PEP Beam-Gas Event Analysis: Physics with the SLAC TPC/2{gamma} Detector; Drift Chamber Tests at Brookhaven National Laboratory; Experiment PR-89-031: Multi-nucleon Knockout Using the CLAS Detector; Electronics Design for the CLAS Region 1 Drift Chamber; Color Transparencies in the Electroproduction of Nucleon Resonances; and Experiment PR-89-015: Study of Coincidence Reactions in the Dip and Delta-Resonance Regions.

  15. Nuclear Energy: Benefits Versus Risks

    ERIC Educational Resources Information Center

    Jordan, Walter H.

    1970-01-01

    Discusses the benefits as well as the risks of nuclear-power plants. Suggests that critics who dwell on the risks to the public from nuclear-power plants should compare these risks with the present hazards that would be eliminated. Bibliography. (LC)

  16. Nuclear energy for the third millennium

    SciTech Connect

    Teller, E.

    1997-10-01

    The major energy sources of today are expected to last for only a small fraction of the millennium starting three years hence. In the plans of most people, nuclear energy has been ruled out for four separate reasons: 1. The danger of radioactivity from a reactor accident or from reactor products during a long period after reactor shutdown; 2. The proposed fuels, U-235 and also Pu-239, as obtained by presently available procedures will serve only for a limited duration; 3. Energy from nuclear reactors will be more expensive than costs of present alternatives; 4. The possibility of misusing the products for military purposes is an unacceptable danger. The development described below 1 attempts to meet all four objections. Specifically, we propose a structure as an example of future reactors that is deployed two hundred meters underground in loose and dry earth. The reactor is designed to function for thirty years, delivering electrical power on demand up to a level of thousand electrical megawatts. From the time that the reactor is started to the time of its shutdown thirty years later, the functioning is to be completely automatic. This is an obviously difficult condition to fulfill. The most important factor in making it possible is to design and operate the reactor without moving mechanical parts. At the start, the reactor functions on thermal neutrons within a structure containing uranium enriched in U-235 or having an addition of plutonium. That part of the reactor is to deliver energy for approximately one year after which a neighboring portion of the reactor containing thorium has been converted into Th-233 which rather rapidly decays into fissile U-233. This part of the assembly works on fission by fast neutrons. It will heat-up if insufficient thermal energy is withdrawn from the reactor`s core, under the negative feedback action of engineered-in thermostats. Indeed, these specifically designed thermostatic units absorb neutrons if excessive reactor core

  17. The Future of Energy from Nuclear Fission

    SciTech Connect

    Kim, Son H.; Taiwo, Temitope

    2013-04-13

    Nuclear energy is an important part of our current global energy system, and contributes to supplying the significant demand for electricity for many nations around the world. There are 433 commercial nuclear power reactors operating in 30 countries with an installed capacity of 367 GWe as of October 2011 (IAEA PRIS, 2011). Nuclear electricity generation totaled 2630 TWh in 2010 representing 14% the world’s electricity generation. The top five countries of total installed nuclear capacity are the US, France, Japan, Russia and South Korea at 102, 63, 45, 24, and 21 GWe, respectively (WNA, 2012a). The nuclear capacity of these five countries represents more than half, 68%, of the total global nuclear capacity. The role of nuclear power in the global energy system today has been motivated by several factors including the growing demand for electric power, the regional availability of fossil resources and energy security concerns, and the relative competitiveness of nuclear power as a source of base-load electricity. There is additional motivation for the use of nuclear power because it does not produce greenhouse gas (GHG) emissions or local air pollutants during its operation and contributes to low levels of emissions throughout the lifecycle of the nuclear energy system (Beerten, J. et. al., 2009). Energy from nuclear fission primarily in the form of electric power and potentially as a source of industrial heat could play a greater role for meeting the long-term growing demand for energy worldwide while addressing the concern for climate change from rising GHG emissions. However, the nature of nuclear fission as a tremendously compact and dense form of energy production with associated high concentrations of radioactive materials has particular and unique challenges as well as benefits. These challenges include not only the safety and cost of nuclear reactors, but proliferation concerns, safeguard and storage of nuclear materials associated with nuclear fuel

  18. MARLEY: Model of Argon Reaction Low Energy Yields

    NASA Astrophysics Data System (ADS)

    Gardiner, Steven; Bilton, Kyle; Grant, Christopher; Pantic, Emilija; Svoboda, Robert

    2015-10-01

    Core-collapse supernovae are sources of tremendous numbers of neutrinos with energies of up to about 50 MeV. In recent years, there has been growing interest in building detectors that are sensitive to supernova neutrinos. Such detectors can provide information about the initial stages of stellar collapse, early warning signals for light emission from supernovae, and opportunities to study neutrino oscillation physics over astronomical distances. In an effort to enable supernova neutrino detection in next-generation experiments like DUNE, the CAPTAIN collaboration plans to make the first direct measurement of cross sections for neutrino interactions on argon in the supernova energy regime. To help predict neutrino event signatures in the CAPTAIN liquid argon time projection chamber (LArTPC), we have developed a first-of-its-kind Monte Carlo event generator called MARLEY (Model of Argon Reaction Low Energy Yields). This generator attempts to model the complicated nuclear structure dependence of low-energy neutrino-nucleus reactions in sufficient detail for use in LArTPC simulations. In this talk we present some preliminary results calculated using MARLEY and discuss how the current version of the generator may be improved and expanded.

  19. On the Role of Nuclear Energy

    ERIC Educational Resources Information Center

    Parsegian, V. Lawrence

    1974-01-01

    The author elaborates on the thesis that much of the confusion and argument about the role of nuclear energy in meeting the energy needs of the nation and the world is caused by failure to place the known facts in perspective with respect to time, to hazards that accompany the use of energy in any form, to economics, and to ultimate limitations in…

  20. Calculation of nuclear reaction cross sections on excited nuclei with the coupled-channels method

    SciTech Connect

    Kawano, T.; Talou, P.; Lynn, J. E.; Chadwick, M. B.; Madland, D. G.

    2009-08-15

    We calculate nuclear cross sections on excited nuclei in the fast neutron energy range. We partition the whole process into two contributions: the direct reaction part and the compound nuclear reactions. A coupled-channels method is used for calculating the direct transition of the nucleus from the initial excited state, which is a member of the ground-state rotational band, to the final ground and excited low-lying levels. This process is strongly affected by the channel coupling. The compound nuclear reactions on the excited state are calculated with the statistical Hauser-Feshbach model, with the transmission coefficients obtained from the coupled-channels calculation. The calculations are performed for a strongly deformed nucleus {sup 169}Tm, and selected cross sections for the ground and first excited states are compared. The calculation is also made for actinides to investigate possible modification to the fission cross section when the target is excited. It is shown that both the level coupling for the entrance channel, and the different target spin, change the fission cross section.

  1. Separable coupled-channels momentum space potentials for nuclear reactions

    NASA Astrophysics Data System (ADS)

    Hlophe, Linda; Eremenko, Vasily; Elster, Charlotte; Nunes, Filomena; Deltuva, Arbanas; Escher, Jutta; Thompson, Ian; Torus Collaboration

    2015-10-01

    Many nuclei are deformed and their properties may be described using a rotational model. This involves defining a deformed surface of the nucleus and constructing the nuclear interaction as a function of distance to the surface. The resulting potential has non-zero matrix elements between different rotational states which are characterized by the nuclear spin-parity Iπ, leading to channel couplings. Our goal is to utilize these coupled-channels potentials in momentum space Faddeev calculations which take into account core excitations. For this purpose their separable representation in momentum space is necessary. We accomplish this by employing the separable representation scheme developed by Ernst, Shakin, and Thaler (EST). Since the potentials are complex, the multichannel EST scheme is generalized to non-Hermitian potentials. In the case of proton-nucleus interactions the EST scheme is further extended to include charged particles. The multichannel EST scheme is applied to scattering off 10Be and 12C. For 10Be only couplings to the first excited state (Iπ =2+) were included while for 12C the first two excited states (Iπ =2+ ,4+) were taken into account. Research for this project was supported in part by the US Department of Energy, Office of Science of Nuclear Physics contact.

  2. NUCLEAR ENERGY SYSTEM COST MODELING

    SciTech Connect

    Francesco Ganda; Brent Dixon

    2012-09-01

    The U.S. Department of Energy’s Fuel Cycle Technologies (FCT) Program is preparing to perform an evaluation of the full range of possible Nuclear Energy Systems (NES) in 2013. These include all practical combinations of fuels and transmuters (reactors and sub-critical systems) in single and multi-tier combinations of burners and breeders with no, partial, and full recycle. As part of this evaluation, Levelized Cost of Electricity at Equilibrium (LCAE) ranges for each representative system will be calculated. To facilitate the cost analyses, the 2009 Advanced Fuel Cycle Cost Basis Report is being amended to provide up-to-date cost data for each step in the fuel cycle, and a new analysis tool, NE-COST, has been developed. This paper explains the innovative “Island” approach used by NE-COST to streamline and simplify the economic analysis effort and provides examples of LCAE costs generated. The Island approach treats each transmuter (or target burner) and the associated fuel cycle facilities as a separate analysis module, allowing reuse of modules that appear frequently in the NES options list. For example, a number of options to be screened will include a once-through uranium oxide (UOX) fueled light water reactor (LWR). The UOX LWR may be standalone, or may be the first stage in a multi-stage system. Using the Island approach, the UOX LWR only needs to be modeled once and the module can then be reused on subsequent fuel cycles. NE-COST models the unit operations and life cycle costs associated with each step of the fuel cycle on each island. This includes three front-end options for supplying feedstock to fuel fabrication (mining/enrichment, reprocessing of used fuel from another island, and/or reprocessing of this island’s used fuel), along with the transmuter and back-end storage/disposal. Results of each island are combined based on the fractional energy generated by each islands in an equilibrium system. The cost analyses use the probability

  3. Activation cross sections of proton induced nuclear reactions on palladium up to 80MeV.

    PubMed

    Tárkányi, F; Ditrói, F; Takács, S; Csikai, J; Hermanne, A; Uddin, M S; Baba, M

    2016-08-01

    Activation cross sections of proton induced nuclear reactions on palladium were measured up to 80MeV by using the stacked foil irradiation technique and gamma ray spectrometry. The beam intensity, the incident energy and the energy degradation were controlled by a method based on flux constancy via normalization to the excitation functions of monitor reactions measured in parallel. Excitation functions for direct and cumulative cross-sections were measured for the production of (104m,104g,105g,106m,110m)Ag, (100,101)Pd, (99m,99g,100,101m,101g,102m,102g,105)Rh and (103,97)Ru radioisotopes. The cross section data were compared with the theoretical predictions of TENDL-2014 and -2015 libraries. For practical applications thick target yields were derived from the measured excitation functions. Application in the field of medical radionuclide production is shortly discussed. PMID:27235887

  4. Oxygen determination in materials by 18O(p,αγ)15N nuclear reaction

    NASA Astrophysics Data System (ADS)

    Kumar, Sanjiv; Sunitha, Y.; Reddy, G. L. N.; Sukumar, A. A.; Ramana, J. V.; Sarkar, A.; Verma, Rakesh

    2016-07-01

    The paper presents a proton induced γ-ray emission method based on 18O(p,αγ)15N nuclear reaction to determine bulk oxygen in materials. The determination involves the measurement of 5.27 MeV γ-rays emitted following the de-excitation of 15N nuclei. A description of the energetics of the reaction is given to provide an insight into the origin of 5.27 MeV γ-rays. In addition, thick target γ-ray yields and the limits of detection are measured to ascertain the analytical potential of the reaction. The thick-target γ-ray yields are measured with a high purity germanium detector and a bismuth germanate detector at 0° as well as 90° angles in 3.0-4.2 MeV proton energy region. The best limit of detection of about 1.3 at.% is achieved at 4.2 MeV proton energy for measurements at 0° as well 90° angles with the bismuth germanate detector while the uncertainty in quantitative analysis is <8%. The reaction has a probing depth of several tens of microns. Interferences can arise from fluorine due to the occurrence of 19F(p,αγ)16O reaction that emits 6-7 MeV γ-rays. The analytical potential of the methodology is demonstrated by determining oxygen in several oxide as well as non-oxide materials.

  5. The nuclear energy outlook--a new book from the OECD nuclear energy agency.

    PubMed

    Yoshimura, Uichiro

    2011-01-01

    This paper summarizes the key points of a report titled Nuclear Energy Outlook, published in 2008 by the Nuclear Energy Agency of the Organization for Economic Cooperation and Development, which has 30 member nations. The report discusses the commitment of many nations to increase nuclear power generating capacity and the potential rate of building new electricity-generating nuclear plants by 2030 to 2050. The resulting decrease in carbon dioxide emissions from fossil fuel combustion resulting from an increase in nuclear power sources is described. Other topics that are discussed include the need to develop non-proliferative nuclear fuels, the importance of developing geological disposal facilities or reprocessing capabilities for spent nuclear fuel and high-level radioactive waste materials, and the requirements for a larger nuclear workforce and greater cost competitiveness for nuclear power generation.

  6. The nuclear energy outlook--a new book from the OECD nuclear energy agency.

    PubMed

    Yoshimura, Uichiro

    2011-01-01

    This paper summarizes the key points of a report titled Nuclear Energy Outlook, published in 2008 by the Nuclear Energy Agency of the Organization for Economic Cooperation and Development, which has 30 member nations. The report discusses the commitment of many nations to increase nuclear power generating capacity and the potential rate of building new electricity-generating nuclear plants by 2030 to 2050. The resulting decrease in carbon dioxide emissions from fossil fuel combustion resulting from an increase in nuclear power sources is described. Other topics that are discussed include the need to develop non-proliferative nuclear fuels, the importance of developing geological disposal facilities or reprocessing capabilities for spent nuclear fuel and high-level radioactive waste materials, and the requirements for a larger nuclear workforce and greater cost competitiveness for nuclear power generation. PMID:21399406

  7. Mass and charge distributions in chlorine-induced nuclear reactions

    SciTech Connect

    Marchetti, A.A.

    1991-12-31

    Projectile-like fragments were detected and characterized in terms of A, Z, and energy for the reactions {sup 37}Cl on {sup 40}Ca and {sup 209}Bi at E/A = 7.3 MeV, and {sup 35}Cl, on {sup 209}Bi at E/A = 15 MeV, at angles close to the grazing angle. Mass and charge distributions were generated in the N-Z plane as a function of energy loss, and have been parameterized in terms of their centroids, variances, and coefficients of correlation. Due to experimental problems, the mass resolution corresponding to the {sup 31}Cl on {sup 209}Bi reaction was very poor. This prompted the study and application of a deconvolution technique for peak enhancement. The drifts of the charge and mass centroids for the system {sup 37}Cl on {sup 40}Ca are consistent with a process of mass and charge equilibration mediated by nucleon exchange between the two partners, followed by evaporation. The asymmetric systems show a strong drift towards larger asymmetry, with the production of neutron-rich nuclei. It was concluded that this is indicative of a net transfer of protons from the light to the heavy partner, and a net flow of neutrons in the opposite direction. The variances for all systems increase with energy loss, as it would be expected from a nucleon exchange mechanism; however, the variances for the reaction {sup 37}Cl on {sup 40}Ca are higher than those expected from that mechanism. The coefficients of correlation indicate that the transfer of nucleons between projectile and target is correlated. The results were compared to the predictions of two current models based on a stochastic nucleon exchange mechanism. In general, the comparisons between experimental and predicted variances support this mechanism; however, the need for more realistic driving forces in the model calculations is indicated by the disagreement between predicted and experimental centroids.

  8. Determination of the helium diffusion coefficient in nuclear waste storage ceramics by a nuclear reaction analysis method

    NASA Astrophysics Data System (ADS)

    Gosset, Dominique; Trocellier, Patrick; Serruys, Yves

    2002-06-01

    Host matrices for actinide immobilisation will undergo the formation of large helium quantities due to alpha decay. Helium diffusion rate has to be known in order to predict the long-term behaviour of the material, and particularly, the influence of helium accumulation on mechanical properties. A nuclear reaction analysis method, namely the 3He(d, p) 4He reaction, has been used to analyse the evolution of 3He profiles after ion implantations at 1 and 3 MeV in two materials, monoclinic ZrO 2 (as a test material) and Ca 9Nd(PO 4) 5(SiO 4)F 1.5(OH) 0.5 britholite (envisaged for Am and Pu long-term storage). Two data processing methods are used: the classical excitation curve (proton yields versus deuteron energy) and second, the proton energy spectrum for a given deuteron energy. The characteristics of the 3He profiles (depth, width) obtained by both methods are compared to SRIM estimations. Their evolution during subsequent annealings allows an estimation of the helium diffusion rate in the britholite: D ( cm2/ s)=(2.5±1.5)×10 -4exp(-(1.07±0.03 eV)/ kT) in the temperature range 200-400 °C, in agreement with previous results on similar materials. Moreover, the shape of the proton energy spectra suggests channeling effects in britholite.

  9. Public Acceptance of Nuclear Energy in Mexico

    SciTech Connect

    Ramirez-Sanchez, Jose R.; Alonso, Gustavo; Palacios, H. Javier

    2006-07-01

    The nuclear energy is attracting renewed interest of public and policy makers due to his potential role in long term strategies aiming to reduce the risk of global warming and in a more general, to carry out sustainable policies, however, any project of nuclear nature arise concerns about the risks associated with the release of radioactivity during accident conditions, radioactive waste disposal and nuclear weapons proliferation. Then in light of the likeliness for a new nuclear project in Mexico, is necessary to design a strategy to improve the social acceptance of nuclear power. This concern is been boarding since the environmental and economic point of view. The information that can change the perception of nuclear energy towards increase public acceptance, should be an honest debate about the benefits of nuclear energy, of course there are questions and they have to be answered, but in a realistic and scientific way: So thinking in Mexico as a first step it is important to communicate to the government entities and political parties that nuclear energy is a proven asset that it is emission free and safe. Of course besides the guarantee of a proven technology, clean and safe relies the economic fact, and in Mexico this could be the most important aspect to communicate to key people in government. Based in the Laguna Verde survey it is clear that we have to find the adequate means to distribute the real information concerning nuclear technology to the public, because the results shows that Mexican people does not have complete information about nuclear energy, but public can support it when they have enough information. From the IAEA study we can say that in Mexico public acceptance of nuclear energy it s not so bad, is the highest percentage of acceptance of nuclear technology for health, considering benefits to the environment Mexican opposition to build new plants is the second less percentage, and generally speaking 60% of the people accept somehow nuclear

  10. Advanced nuclear energy analysis technology.

    SciTech Connect

    Gauntt, Randall O.; Murata, Kenneth K.; Romero, Vicente JosÔe; Young, Michael Francis; Rochau, Gary Eugene

    2004-05-01

    A two-year effort focused on applying ASCI technology developed for the analysis of weapons systems to the state-of-the-art accident analysis of a nuclear reactor system was proposed. The Sandia SIERRA parallel computing platform for ASCI codes includes high-fidelity thermal, fluids, and structural codes whose coupling through SIERRA can be specifically tailored to the particular problem at hand to analyze complex multiphysics problems. Presently, however, the suite lacks several physics modules unique to the analysis of nuclear reactors. The NRC MELCOR code, not presently part of SIERRA, was developed to analyze severe accidents in present-technology reactor systems. We attempted to: (1) evaluate the SIERRA code suite for its current applicability to the analysis of next generation nuclear reactors, and the feasibility of implementing MELCOR models into the SIERRA suite, (2) examine the possibility of augmenting ASCI codes or alternatives by coupling to the MELCOR code, or portions thereof, to address physics particular to nuclear reactor issues, especially those facing next generation reactor designs, and (3) apply the coupled code set to a demonstration problem involving a nuclear reactor system. We were successful in completing the first two in sufficient detail to determine that an extensive demonstration problem was not feasible at this time. In the future, completion of this research would demonstrate the feasibility of performing high fidelity and rapid analyses of safety and design issues needed to support the development of next generation power reactor systems.

  11. 18 CFR 1316.9 - Nuclear energy hazards and nuclear incidents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Nuclear energy hazards... Text of Conditions and Certifications § 1316.9 Nuclear energy hazards and nuclear incidents. When so... documents or actions: Nuclear Energy Hazards and Nuclear Incidents (Applicable only to contracts for...

  12. 18 CFR 1316.9 - Nuclear energy hazards and nuclear incidents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Nuclear energy hazards... Text of Conditions and Certifications § 1316.9 Nuclear energy hazards and nuclear incidents. When so... documents or actions: Nuclear Energy Hazards and Nuclear Incidents (Applicable only to contracts for...

  13. 18 CFR 1316.9 - Nuclear energy hazards and nuclear incidents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Nuclear energy hazards... Text of Conditions and Certifications § 1316.9 Nuclear energy hazards and nuclear incidents. When so... documents or actions: Nuclear Energy Hazards and Nuclear Incidents (Applicable only to contracts for...

  14. 18 CFR 1316.9 - Nuclear energy hazards and nuclear incidents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Nuclear energy hazards... Text of Conditions and Certifications § 1316.9 Nuclear energy hazards and nuclear incidents. When so... documents or actions: Nuclear Energy Hazards and Nuclear Incidents (Applicable only to contracts for...

  15. 18 CFR 1316.9 - Nuclear energy hazards and nuclear incidents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Nuclear energy hazards... Text of Conditions and Certifications § 1316.9 Nuclear energy hazards and nuclear incidents. When so... documents or actions: Nuclear Energy Hazards and Nuclear Incidents (Applicable only to contracts for...

  16. Nuclear spectroscopy study of the isotopes populated via multinucleon transfer in the 90Zr + 208Pb reaction

    SciTech Connect

    Ur, C. A.; Corradi, L.; Stefanini, A. M.; Behera, B. R.; Fioretto, E.; Gadea, A.; Latina, A.; Szilner, S.; Beghini, S.; Farnea, E.; Montagnoli, G.; Scarlassara, F.; Haas, F.; Pollarolo, G.

    2006-08-14

    The present work takes advantage of the multinucleon transfer mechanism between heavy reaction partners to study the population pattern of excited nuclear states in near spherical Zirconium isotopes following the 90Zr + 208Pb reaction at an energy closed to the Coulomb barrier. Both the projectile and the target are well known closed shell nuclei offering an optimum situation for clean experimental and theoretical conditions. Total kinetic energy loss (TKEL) distributions were compared with calculations performed with the GRAZING code. The ability to use the TKEL as a selection tool for the states at different excitation energies was shown.

  17. A perfect match: Nuclear energy and the National Energy Strategy

    SciTech Connect

    Not Available

    1990-11-01

    In the course of developing the National Energy Strategy, the Department of Energy held 15 public hearings, heard from more than 375 witnesses and received more than 1000 written comments. In April 1990, the Department published an Interim Report on the National Energy Strategy, which compiles those public comments. The National Energy Strategy must be based on actual experience and factual analysis of our energy, economic and environmental situation. This report by the Nuclear Power Oversight committee, which represents electric utilities and other organizations involved in supplying electricity from nuclear energy to the American people, provides such an analysis. The conclusions here are based on hard facts and actual worldwide experience. This analysis of all the available data supports -- indeed, dictates -- expanded reliance on nuclear energy in this nation's energy supply to achieve the President's goals. 33 figs.

  18. Nuclear Reactions X-Sections By Evaporation Model, Gamma-Cascades

    2000-06-27

    Calculation of energy-averaged cross sections for nuclear reactions with emission of particles and gamma rays and fission. The models employed are the evaporation model with inclusion of pre-equilibrium decay and gamma ray cascade model. Angular momentum and parity conservation are accounted for. Major improvement to the 1976 STAPRE program (NEA 0461) relates to level density approach, implemwnted in subroutine ZSTDE. Generalized superfluid model is incorporated, Boltzman-gas modelling of intrinsic state density and semi-empirical modelling ofmore » a few quasiparticle effects in total level density in equilibrium and saddle deformations of actinide nuclei.« less

  19. Nuclear Energy Encore in Sweden.

    ERIC Educational Resources Information Center

    Fishlock, David

    1991-01-01

    This article traces Sweden's decision to indefinitely delay their previous plan to phase out nuclear power generators which had been scheduled for 1995. Discussed as major factors in this delay are the excellent safety record of current reactors and the unacceptable economic, as well as environmental, consequences of switching to other power…

  20. Nucleus-nucleus total reaction cross sections, and the nuclear interaction radius

    SciTech Connect

    Abu-Ibrahim, Badawy

    2011-04-15

    We study the nucleus-nucleus total reaction cross sections for stable nuclei, in the energy region from 30A MeV to about 1A GeV, and find them to be in proportion to ({radical}({sigma}{sub pp}{sup tot}Z{sub 1}{sup 2/3}+{sigma}{sub pn}{sup tot}N{sub 1}{sup 2/3})+{radical}({sigma}{sub pp}{sup tot}Z{sub 2}{sup 2/3}+{sigma}{sub pn}{sup tot}N{sub 2}{sup 2/3})) {sup 2} in the mass range 8 to 100. Also, we find a parameter-free relation that enables us to predict a total reaction cross section for any nucleus-nucleus within 10% uncertainty at most, using the experimental value of the total reaction cross section of a given nucleus-nucleus. The power of the relation is demonstrated by several examples. The energy dependence of the nuclear interaction radius is deduced; it is found to be almost constant in the energy range from about 200A MeV to about 1A GeV; in this energy range and for nuclei with N=Z, R{sub I}(A)=(1.14{+-}0.02)A{sup 1/3} fm.

  1. Effects of isospin dynamics on neck fragmentation in isotopic nuclear reactions

    NASA Astrophysics Data System (ADS)

    Feng, Zhao-Qing

    2016-07-01

    The neck dynamics in Fermi-energy heavy-ion collisions, to probe the nuclear symmetry energy in the domain of subsaturation densities, is investigated within an isospin-dependent transport model. The single and double ratios of neutrons to protons from free nucleons and light clusters (complex particles) in the isotopic reactions are analyzed systematically. Isospin effects of particles produced from the neck fragmentations are explored. It is found that the ratios of the energetic isospin particles strongly depend on the stiffness of the nuclear symmetry energy and the effects increase with softening of the symmetry energy, which would be a nice probe for extracting the symmetry energy below the normal density in experiments. A flat structure appears at the tail spectra from the double ratio distributions. The neutron to proton ratio of light intermediate-mass fragments with charge number Z ≤8 is related to the density dependence of the symmetry energy with less sensitivity in comparison to the isospin ratios of nucleons and light particles.

  2. Nuclear Hybrid Energy Systems: Challenges and Opportunities

    SciTech Connect

    P. Sabharwall; S.B. Sitton; S.J. Yoon; C. Stoots

    2014-07-01

    With growing demand of energy and costs of the fossil fuels, coupled with the environmental concerns have resulted in an increased interest in alternative energy sources. Nuclear hybrid energy systems (NHES) are being considered which incorporates renewable energy sources such as solar and wind energy combined with nuclear reactor and energy storage to meet the peak hours demand imposed on the grid, along with providing process heat for other potential industrial applications. This concept could potentially satisfy various energy demands and improve reliability, robustness and resilience for the entire system as a whole, along with economic and net efficiency gains. This paper provides a brief understanding of potential NHES system and architecture along with the challenges

  3. Study on astrophysical reactions using low-energy RI beams

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Hidetoshi

    2009-10-01

    In recent years, low-energy RI beams can be produced in a good intensity and they have been used for studying many astrophysical reactions. One of the facilities producing low-energy RI beams is CRIB (CNS Radio-Isotope Beam separator) [1,2], an RI-beam separator of Center for Nuclear Study, University of Tokyo. Taking CRIB as an example, recent improvements on the RI-beam production and experimental results on astrophysical studies are presented. Several experimental approaches have been taken for the studies on astrophysical reactions.The feature of each method are discussed based on real measurements performed at CRIB. One is the direct method, applied for measurements of reactions such as (α,p) [3]. Another is the measurement of proton/alpha resonance scattering using the thick target method in inverse kinematics, by which we can obtain information on the resonances relevant in astrophysical reactions [4,5]. A recent fruitful result was from a measurement of proton resonance scattering using a ^7Be beam [5]. The energy level structure of ^8B, revealed by the experiment, is especially of interest as it is related with the ^7Be(p,γ) ^8B reaction, responsible for the production of ^8B neutrinos in the sun. We successfully determined parameters of resonances in ^8B below 6.7 MeV, which may affect the ^7Be(p,γ)^8B reaction rate at the solar temparature. Indirect methods, such as ANC and the Trojan Horse Method, were also used in some of the measurements.[4pt] [1] S. Kubono et al., Eur. Phys. J. A13 (2002) 217.[0pt] [2] Y. Yanagisawa et al., Nucl. Instrum. Meth. Phys. Res., Sect. A 539 (2005) 74.[0pt] [3] M. Notani et al., Nucl. Phys. A 764 (2004) 113c.[0pt] [4] T. Teranishi et al., Phys. Lett. B 650 (2007) 129.[0pt] [5] H. Yamaguchi et al., Phys. Lett. B 672 (2009) 230.

  4. A Nuclear Energy Elective for "Ungineers"

    ERIC Educational Resources Information Center

    Long, R. L.; And Others

    1975-01-01

    Describes a course in the technology of nuclear energy which responds to the immediate concerns of students in areas such as environmental effects, weapons effects, national energy needs, and medical and forensic applications. Includes a course outline and description of appropriate textbooks, (GS)

  5. The Harnessed Atom: Nuclear Energy & Electricity.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC. Nuclear Energy Office.

    This document is part of a nuclear energy curriculum designed for grades six through eight. The complete kit includes a written text, review exercises, activities for the students, and a teachers guide. The 19 lessons in the curriculum are divided into four units including: (1) "Energy and Electricity"; (2) "Understanding Atoms and Radiation"; (3)…

  6. ICENES `91:Sixth international conference on emerging nuclear energy systems. Program and abstracts

    SciTech Connect

    Not Available

    1991-12-31

    This document contains the program and abstracts of the sessions at the Sixth International Conference on Emerging Nuclear Energy Systems held June 16--21, 1991 at Monterey, California. These sessions included: The plenary session, fission session, fission and nonelectric session, poster session 1P; (space propulsion, space nuclear power, electrostatic confined fusion, fusion miscellaneous, inertial confinement fusion, {mu}-catalyzed fusion, and cold fusion); Advanced fusion session, space nuclear session, poster session 2P, (nuclear reactions/data, isotope separation, direct energy conversion and exotic concepts, fusion-fission hybrids, nuclear desalting, accelerator waste-transmutation, and fusion-based chemical recycling); energy policy session, poster session 3P (energy policy, magnetic fusion reactors, fission reactors, magnetically insulated inertial fusion, and nuclear explosives for power generation); exotic energy storage and conversion session; and exotic energy storage and conversion; review and closing session.

  7. Tables of Nuclear Cross Sections and Reaction Rates: AN Addendum to the Paper ``ASTROPHYSICAL Reaction Rates from Statistical Model Calculations'' ()

    NASA Astrophysics Data System (ADS)

    Rauscher, Thomas; Thielemann, Friedrich-Karl

    2001-09-01

    In a previous publication (ATOMIC DATAAND NUCLEAR DATA TABLES75, 1 (2000)), we gave seven-parameter analytical fits to theoretical reaction rates derived from nuclear cross sections calculated in the statistical model (Hauser-Feshbach formalism) for targets with 10<=Z<=83 (Ne to Bi) and for a mass range reaching the neutron and proton driplines. Reactions considered were (n,γ), (n,p), (n,α), (p,γ), (p,α), (α,γ), and their inverse reactions. Here, we present the theoretical nuclear cross sections and astrophysical reaction rates from which those rate fits were derived, and we provide these data as on-line electronic files. Corresponding to the fitted rates, two complete data sets are provided, one of which includes a phenomenological treatment of shell quenching for neutron-rich nuclei.

  8. Nuclear Energy for Space Exploration

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.

    2010-01-01

    Nuclear power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system. Fusion and antimatter systems may also be viable in the future

  9. Nuclear matter at a HIRFL-CSR energy regime

    NASA Astrophysics Data System (ADS)

    Xiao, Zhigang; Chen, Lie-Wen; Fu, Fen; Li, Bao-An; Jin, Genming; Xu, Hushan; Yong, Gaochan; Zhang, Ming

    2009-06-01

    We report some recent progress in constraining the symmetry energy Esym(ρ) at high densities using high-energy heavy-ion collisions. Circumstantial evidence of a soft Esym(ρ) at supra-saturation density is obtained by comparing the pion ratio π-/π+ measured recently with FOPI at GSI and the IBUU04 model calculations. Detailed studies indicate that the power of determining the Esym(ρ) from π-/π+ is enhanced with decreasing the beam energy to near the pion production threshold, showing a correlation to the increasing nuclear stopping. Among several heavy-ion reaction facilities in the world, the cooling storage ring (HIRFL-CSR), newly commissioned at Lanzhou, delivering heavy-ion beams up to 1 A GeV, to be coupled with advanced detectors will contribute significantly to further studies of the equation of state of asymmetric nuclear matter.

  10. Computed potential energy surfaces for chemical reactions

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.

    1988-01-01

    The minimum energy path for the addition of a hydrogen atom to N2 is characterized in CASSCF/CCI calculations using the (4s3p2d1f/3s2p1d) basis set, with additional single point calculations at the stationary points of the potential energy surface using the (5s4p3d2f/4s3p2d) basis set. These calculations represent the most extensive set of ab initio calculations completed to date, yielding a zero point corrected barrier for HN2 dissociation of approx. 8.5 kcal mol/1. The lifetime of the HN2 species is estimated from the calculated geometries and energetics using both conventional Transition State Theory and a method which utilizes an Eckart barrier to compute one dimensional quantum mechanical tunneling effects. It is concluded that the lifetime of the HN2 species is very short, greatly limiting its role in both termolecular recombination reactions and combustion processes.

  11. Systematic Error Estimation for Chemical Reaction Energies.

    PubMed

    Simm, Gregor N; Reiher, Markus

    2016-06-14

    For a theoretical understanding of the reactivity of complex chemical systems, accurate relative energies between intermediates and transition states are required. Despite its popularity, density functional theory (DFT) often fails to provide sufficiently accurate data, especially for molecules containing transition metals. Due to the huge number of intermediates that need to be studied for all but the simplest chemical processes, DFT is, to date, the only method that is computationally feasible. Here, we present a Bayesian framework for DFT that allows for error estimation of calculated properties. Since the optimal choice of parameters in present-day density functionals is strongly system dependent, we advocate for a system-focused reparameterization. While, at first sight, this approach conflicts with the first-principles character of DFT that should make it, in principle, system independent, we deliberately introduce system dependence to be able to assign a stochastically meaningful error to the system-dependent parametrization, which makes it nonarbitrary. By reparameterizing a functional that was derived on a sound physical basis to a chemical system of interest, we obtain a functional that yields reliable confidence intervals for reaction energies. We demonstrate our approach on the example of catalytic nitrogen fixation.

  12. Nuclear Reactions: Studying Peaceful Applications in the Middle and Secondary School.

    ERIC Educational Resources Information Center

    Szymanski Sunal, Cynthia; Sunal, Dennis W.

    1999-01-01

    Asserts that students must learn about nuclear fission and fusion in the social studies curriculum to help them develop a foundation for considering the social issues associated with the everyday use of nuclear reactions. Gives background on the two types of reactions and provides three lessons for middle and secondary classrooms. (CMK)

  13. Estimation of Nuclear Reaction Effects in Proton-Tissue-Dose Calculations.

    1983-01-14

    Version 00 REPC reviews calculational methods for the estimation of dose from external proton exposure of arbitrary convex bodies and presents the necessary information for the estimation of dose in soft tissue. The effects of nuclear reactions, especially in relation to the dose equivalent, are retained. REPC subroutines can be used to convert existing computer programs which neglect nuclear reaction effects to include them.

  14. Multicomponent Molecular Orbital-Climbing Image-Nudged Elastic Band Method to Analyze Chemical Reactions Including Nuclear Quantum Effect.

    PubMed

    Udagawa, Taro; Suzuki, Kimichi; Tachikawa, Masanori

    2015-10-26

    To analyze the H/D isotope effects on hydrogen transfer reactions in XHCHCHCHY↔XCHCHCHYH (X, Y=O, NH, or CH2 ) including the nuclear quantum effect of proton and deuteron, we propose a multicomponent molecular orbital-climbing image-nudged elastic band (MC_MO-CI-NEB) method. We obtain not only transition state structures but also minimum-energy paths (MEPs) on the MC_MO effective potential energy surface by using MC_MO-CI-NEB method. We find that nuclear quantum effect affects not only stationary-point geometries but also MEPs and electronic structures in the reactions. We clearly demonstrate the importance of including nuclear quantum effects for H/D isotope effect on rate constants (kH /kD ).

  15. Advancing the Theory of Nuclear Reactions with Rare Isotopes. From the Laboratory to the Cosmos

    SciTech Connect

    Nunes, Filomena

    2015-06-01

    The mission of the Topical Collaboration on the Theory of Reactions for Unstable iSotopes (TORUS) was to develop new methods to advance nuclear reaction theory for unstable isotopes—particularly the (d,p) reaction in which a deuteron, composed of a proton and a neutron, transfers its neutron to an unstable nucleus. After benchmarking the state-of-the-art theories, the TORUS collaboration found that there were no exact methods to study (d,p) reactions involving heavy targets; the difficulty arising from the long-range nature of the well known, yet subtle, Coulomb force. To overcome this challenge, the TORUS collaboration developed a new theory where the complexity of treating the long-range Coulomb interaction is shifted to the calculation of so-called form-factors. An efficient implementation for the computation of these form factors was a major achievement of the TORUS collaboration. All the new machinery developed are essential ingredients to analyse (d,p) reactions involving heavy nuclei relevant for astrophysics, energy production, and stockpile stewardship.

  16. Attitudes and reactions to nuclear weapons: responses to fear arousal

    SciTech Connect

    Herman, K.L.

    1987-01-01

    This study employed a pre-posttest design to investigate how degree of commitment to a preventive nuclear war strategy, and various demographic characteristics influence nuclear-war-related factors. Two hundred sixteen college students were assigned to one of four groups. Subjects in the first two groups completed the pretest, and waited three weeks before receiving the posttest. The posttest asked subjects in the first group to imagine and write about what might happen to them in the event of a major nuclear war, and re-administered the pretest research questions. Individuals in the second group responded to a fantasy on earthquakes, followed by the posttest. Subjects in the third group responded only to the nuclear was fantasy and theposttest, while those individuals in the fourth group were administered the posttest only. Subjects committed to a strategy considered their chance of death by nuclear war more likely after the nuclear-war fantasy than after the earthquake fantasy. Subjects uncommitted viewed their chance of death by nuclear was as less likely after the nuclear war fantasy than after the earthquake fantasy. This supports previous research indicating that cognitive strategies may be employed to reduce fear arousal. Women reported greater (a) chance of death by nuclear war, (b) nuclear anxiety, (c) nuclear concern, and (d) fear of the future than men. Subjects committed to a strategy expressed greater nuclear concern, greater nuclear anxiety, and employed less nuclear denial than those who were uncommitted.

  17. 3D reconstruction of nuclear reactions using GEM TPC with planar readout

    SciTech Connect

    Bihałowicz, Jan Stefan

    2015-02-24

    The research program of the Extreme Light Infrastructure – Nuclear Physics (ELI-NP) laboratory under construction in Magurele, Romania facilities the need of developing a gaseous active-target detector providing 3D reconstruction of charged products of nuclear reactions induced by gamma beam. The monoenergetic, high-energy (E{sub γ} > 19 MeV) gamma beam of intensity 10{sup 13}γ/s allows studying nuclear reactions in astrophysics. A Time Projection Chamber with crossed strip readout (eTPC) is proposed as one of the imaging detectors. The special feature of the readout electrode structure is a 2D reconstruction based on the information read out simultaneously from three arrays of strips that form virtual pixels. It is expected to reach similar spatial resolution as for pixel readout at largely reduced cost of electronics. The paper presents the current progress and first results of the small scale prototype TPC which is a one of implementation steps towards eTPC detector proposed in the Technical Design Report of Charged Particles Detection at ELI-NP.

  18. Nuclear structure studies with medium energy probes. [Northwestern Univ

    SciTech Connect

    Seth, Kamal K.

    1980-01-01

    Progress in the continuing program of experimental research in nuclear structure with medium-energy probes during the year 1979-1980 is reviewed, and the research activities planned for the year 1980-1981 are discussed. In the study of pion-induced reactions emphasis is placed on investigation of isovector characteristics of nuclear excitations and on double charge exchange reactions. Pion production studies form the major part of the program of experiments with proton beams of 400 to 800 MeV at LAMPF. Current emphasis is on the bearing of these investigations on di-baryon existence. The study of high-spin states and magnetic scattering constitute the main goals of the electron scattering program at Bates. Representative results are presented; completed work is reported in the usual publications. (RWR)

  19. A nuclear reaction analysis and optical microscopy study on controlled growth of large SiC nanocrystals on Si formed by low-energy ion implantation and electron beam annealing

    NASA Astrophysics Data System (ADS)

    Markwitz, A.; Lucas, F.; Rusterucci, J.; Kennedy, J.; Trompetter, W. J.; Rudolphi, M.; Ryan, M.; White, V.; Johnson, S.

    2006-08-01

    Ion implantation of 20 keV 12C+ ions into (1 0 0), p-type silicon with ion fluence of 8 × 1016 at. cm-2 followed by an electron beam annealing under high vacuum conditions has been performed to investigate the formation of crystalline nano-scale SiC features on the silicon surface. Depending on the implantation and annealing conditions, the SiC nanocrystal numbers and average spacing can be controlled by adjusting the implantation and annealing conditions. Typically 300-1000 SiC nanocrystals are produced per 1000 μm2 spaced 0.7-1.2 ± 0.1 μm. Nuclear reaction analysis measurements using the deuterium induced 12C(d, p)13C reaction show that carbon is present in the implanted and annealed samples and varies only to a small degree by the annealing time. However, by not using a liquid nitrogen trap surrounding the targets during implantation, the carbon contamination on the surface reduces the number of SiC nanocrystals and increases their average distance. Specific results are discussed.

  20. Nuclear reaction measurements on tissue-equivalent materials and GEANT4 Monte Carlo simulations for hadrontherapy

    NASA Astrophysics Data System (ADS)

    De Napoli, M.; Romano, F.; D'Urso, D.; Licciardello, T.; Agodi, C.; Candiano, G.; Cappuzzello, F.; Cirrone, G. A. P.; Cuttone, G.; Musumarra, A.; Pandola, L.; Scuderi, V.

    2014-12-01

    When a carbon beam interacts with human tissues, many secondary fragments are produced into the tumor region and the surrounding healthy tissues. Therefore, in hadrontherapy precise dose calculations require Monte Carlo tools equipped with complex nuclear reaction models. To get realistic predictions, however, simulation codes must be validated against experimental results; the wider the dataset is, the more the models are finely tuned. Since no fragmentation data for tissue-equivalent materials at Fermi energies are available in literature, we measured secondary fragments produced by the interaction of a 55.6 MeV u-1 12C beam with thick muscle and cortical bone targets. Three reaction models used by the Geant4 Monte Carlo code, the Binary Light Ions Cascade, the Quantum Molecular Dynamic and the Liege Intranuclear Cascade, have been benchmarked against the collected data. In this work we present the experimental results and we discuss the predictive power of the above mentioned models.

  1. A reexamination of the abrasion-ablation model for the description of the nuclear fragmentation reaction

    NASA Astrophysics Data System (ADS)

    Gaimard, J.-J.; Schmidt, K.-H.

    1991-09-01

    The nuclear fragmentation reaction is studied as an important production mechanism for secondary beams. The geometrical abrasion model and a macroscopic evaporation model which describe the two steps of the reaction are reexamined. Several improvements and modifications of these models are discussed and a new model description incorporating these elements is proposed. In particular, the excitation energy and the angular-momentum distribution of the prefragments, the formulation of evaporation as a diffusion process and the role of microscopic structure in the production cross section are considered. The new model description preserves the simplicity and the transparency of the original models. The prediction of the new model are compared to those of the original models and to experimental cross sections. While the original models showed several systematic discrepancies in comparison to measured cross sections, the new model is able to reproduce the whole body of experimental data with satisfactory agreement.

  2. Coal and nuclear power: Illinois' energy future

    SciTech Connect

    Not Available

    1982-01-01

    This conference was sponsored by the Energy Resources Center, University of Illinois at Chicago; the US Department of Energy; the Illinois Energy Resources Commission; and the Illinois Department of Energy and Natural Resources. The theme for the conference, Coal and Nuclear Power: Illinois' Energy Future, was based on two major observations: (1) Illinois has the largest reserves of bituminous coal of any state and is surpassed in total reserves only by North Dakota, and Montana; and (2) Illinois has made a heavy commitment to the use of nuclear power as a source of electrical power generation. Currently, nuclear power represents 30% of the electrical energy produced in the State. The primary objective of the 1982 conference was to review these two energy sources in view of the current energy policy of the Reagan Administration, and to examine the impact these policies have on the Midwest energy scene. The conference dealt with issues unique to Illinois as well as those facing the entire nation. A separate abstract was prepared for each of the 30 individual presentations.

  3. Particle-gamma and particle-particle correlations in nuclear reactions using Monte Carlo Hauser-Feshback model

    SciTech Connect

    Kawano, Toshihiko; Talou, Patrick; Watanabe, Takehito; Chadwick, Mark

    2010-01-01

    Monte Carlo simulations for particle and {gamma}-ray emissions from an excited nucleus based on the Hauser-Feshbach statistical theory are performed to obtain correlated information between emitted particles and {gamma}-rays. We calculate neutron induced reactions on {sup 51}V to demonstrate unique advantages of the Monte Carlo method. which are the correlated {gamma}-rays in the neutron radiative capture reaction, the neutron and {gamma}-ray correlation, and the particle-particle correlations at higher energies. It is shown that properties in nuclear reactions that are difficult to study with a deterministic method can be obtained with the Monte Carlo simulations.

  4. 75 FR 14638 - FirstEnergy Nuclear Operating Company; Perry Nuclear Power Plant; Environmental Assessment and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-26

    ... COMMISSION FirstEnergy Nuclear Operating Company; Perry Nuclear Power Plant; Environmental Assessment and...Energy Nuclear Operating Company (FENOC, the licensee), for operation of the Perry Nuclear Power Plant... Manager, Plant Licensing Branch III-2, Division of Operating Reactor Licensing, Office of Nuclear...

  5. Theoretical studies in high energy nuclear physics. Progress report

    SciTech Connect

    1995-08-01

    This paper is a progress report for the period 1-1-93 to 6-30-95 on a project primarily directed at the application of high energy physics techniques to nuclear structure studies, and the ability to study hadron dynamics through interactions with nuclear targets. This work has included the first legitimate QCD calculations of hard coherent diffractive processes off nucleon (nuclear) targets which established novel features of color transparency phenomenon not anticipated in the previous intuitive or QCD inspired model calculations and predicted the fast increase of the cross section for electroproduction of {rho}-mesons with increase of the energy, which was confirmed very recently by the first HERA data on this reaction. First theoretical demonstration that color transparency phenomenon for the hard diffractive processes follow from QCD in the kinematics when both x{yields}0 and Q{sup 2}{yields}{infinity}. Establishing the pattern of color (cross section) fluctuations in hadrons. Confirmed by the FNAL inelastic diffraction data. Finding that in realistic quark, skyrmion models of a hadron large momentum transfer elastic lepton-hadron scattering occurs through formation of small spatial size configurations. Discovering a novel class of color transparency sensitive double interaction processes which is complementary to quasielastic reactions originally suggested by S. Brodsky and A. Mueller. Adopting ideas suggested elsewhere for hadron initiated reactions they developed a method for taking into account nuclear correlations in (e,e{prime}p) reactions. Such an approach gives practical possibility to overcome ambiguities of optical model approximation used before and to reliably interpret color transparency effects at intermediate Q{sup 2}.

  6. Criteria for Global Nuclear Energy Development

    SciTech Connect

    Lawrence, Michael J.

    2002-07-01

    Global energy consumption will at least double over the next fifty years due to population growth, increased consumption, and an urgent need to improve the standard of living in under-developed countries. Thirty percent of this growth will be for electricity. At the same time, carbon emissions must be significantly reduced to respond to concerns regarding global warming. The use of nuclear energy to meet this growing electricity demand without carbon emissions is an obvious solution to many observers, however real concerns over economics, safety, waste and proliferation must be adequately addressed. The issue is further complicated by the fact that developing countries, which have the most pressing need for additional electricity generation, have the least capability and infrastructure to deploy nuclear energy. Nevertheless, if the specific needs of developing countries are appropriately considered now as new generation reactors are being developed, and institutional arrangements based upon the fundamental principles of President Eisenhower's 1953 Atoms For Peace speech are followed, nuclear energy could be deployed in any country. From a technical perspective, reactor safety and accessibility of special nuclear material are primary concerns. Institutionally, plant and fuel ownership and waste management issues must be addressed. International safety and safeguards authority are prerequisites. While the IAEA's IMPRO program and the United States' Generation IV programs are focusing on technical solutions, institutional issues, particularly with regard to deployment in developing countries, are not receiving corresponding attention. Full-service, cradle-to-grave, nuclear electricity companies that retain custody and responsibility for the plant and materials, including waste, are one possible solution. Small modular reactors such as the Pebble Bed Modular Reactor could be ideal for such an arrangement. While waste disposal remains a major obstacle, this is already

  7. Accelerator Driven Nuclear Energy: The Thorium Option

    SciTech Connect

    Raja, Rajendran

    2009-03-18

    Conventional nuclear reactors use enriched Uranium as fuel and produce nuclear waste which needs to be stored away for over 10,000 years. At the current rate of use, existing sources of Uranium will last for 50-100 years. We describe a solution to the problem that uses particle accelerators to produce fast neutrons that can be used to burn existing nuclear waste and produce energy. Such systems, initially proposed by Carlo Rubbia and collaborators in the 1990's, are being seriously considered by many countries as a possible solution to the green energy problem. Accelerator driven reactors operate in a sub-critical regime and, thus, are safer and can obtain energy from plentiful elements such as Thorium-232 and Uranium-238. What is missing is the high intensity (10MW) accelerator that produces 1 GeV protons. We will describe scenarios which if implemented will make such systems a reality.

  8. The development of nuclear energy in the Philippines

    SciTech Connect

    Aleta, C. )

    1992-01-01

    The paper traces the development of nuclear energy in the Philippines and outlines the program on the peaceful uses of nuclear energy in the country as well as the problems and prospects of nuclear energy development. Nuclear power is at a standstill but the other areas of nuclear energy development are underway. The projects on the application of nuclear energy in agriculture, industry, public health and safety, are being pursued. Technology transfer to end users is sometimes hampered by public acceptance issues, such as irradiated food being believed to become radioactive, dislike with anything associated with radiation, and plain inherent fear of nuclear energy.

  9. Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iriduim and Gold

    SciTech Connect

    Hoffman, R D; Dietrich, F S; Kelley, K; Escher, J; Bauer, R; Mustafa, M

    2008-02-26

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from osmium (Z = 76) to gold (Z = 79). Of particular interest are the cross sections on Ir and Au including reactions on isomeric targets.

  10. Nuclear energy release from fragmentation

    NASA Astrophysics Data System (ADS)

    Li, Cheng; Souza, S. R.; Tsang, M. B.; Zhang, Feng-Shou

    2016-08-01

    It is well known that binary fission occurs with positive energy gain. In this article we examine the energetics of splitting uranium and thorium isotopes into various numbers of fragments (from two to eight) with nearly equal size. We find that the energy released by splitting 230,232Th and 235,238U into three equal size fragments is largest. The statistical multifragmentation model (SMM) is applied to calculate the probability of different breakup channels for excited nuclei. By weighing the probability distributions of fragment multiplicity at different excitation energies, we find the peaks of energy release for 230,232Th and 235,238U are around 0.7-0.75 MeV/u at excitation energy between 1.2 and 2 MeV/u in the primary breakup process. Taking into account the secondary de-excitation processes of primary fragments with the GEMINI code, these energy peaks fall to about 0.45 MeV/u.

  11. 76 FR 23798 - Nuclear Energy Advisory Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Nuclear Energy Advisory Committee; Meeting AGENCY: Office of Nuclear Energy, Department of Energy. ACTION: Notice of open meeting. SUMMARY: This notice announces a meeting of the Nuclear Energy Advisory...

  12. Nuclear Hybrid Energy Systems: Molten Salt Energy Storage

    SciTech Connect

    P. Sabharwall; M. Green; S.J. Yoon; S.M. Bragg-Sitton; C. Stoots

    2014-07-01

    With growing concerns in the production of reliable energy sources, the next generation in reliable power generation, hybrid energy systems, are being developed to stabilize these growing energy needs. The hybrid energy system incorporates multiple inputs and multiple outputs. The vitality and efficiency of these systems resides in the energy storage application. Energy storage is necessary for grid stabilizing and storing the overproduction of energy to meet peak demands of energy at the time of need. With high thermal energy production of the primary nuclear heat generation source, molten salt energy storage is an intriguing option because of its distinct properties. This paper will discuss the different energy storage options with the criteria for efficient energy storage set forth, and will primarily focus on different molten salt energy storage system options through a thermodynamic analysis

  13. 75 FR 16523 - FirstEnergy Nuclear Operating Company; Davis-Besse Nuclear Power Station; Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ... COMMISSION FirstEnergy Nuclear Operating Company; Davis-Besse Nuclear Power Station; Exemption 1.0 Background FirstEnergy Nuclear Operating Company (FENOC, the licensee) is the holder of Facility Operating License... M.S. Fertel, Nuclear Energy Institute). The licensee's request for an exemption is...

  14. Dynamical cluster-decay model for hot and rotating light-mass nuclear systems applied to the low-energy {sup 32}S+{sup 24}Mg{yields}{sup 56}Ni{sup *} reaction

    SciTech Connect

    Gupta, Raj K.; Kumar, Rajesh; Singh, Dalip; Balasubramaniam, M.; Beck, C.

    2005-01-01

    The dynamical cluster-decay model (DCM) is developed further for the decay of hot and rotating compound nuclei (China) formed in light heavy-ion reactions. The model is worked out in terms of only one parameter, namely the neck-length parameter, which is related to the total kinetic energy TKE(T) or effective Q value Q{sub eff}(T) at temperature T of the hot CN and is defined in terms of the CN binding energy and ground-state binding energies of the emitted fragments. The emission of both the light particles (LP), with A{<=}4,Z{<=}2, as well as the complex intermediate mass fragments (IMF), with 42, is considered as the dynamical collective mass motion of preformed clusters through the barrier. Within the same dynamical model treatment, the LPs are shown to have different characteristics compared to those of the IMFs. The systematic variations of the LP emission cross section {sigma}{sub LP} and IMF emission cross section {sigma}{sub IMF} calculated from the present DCM match exactly the statistical fission model predictions. A nonstatistical dynamical description is developed for the first time for emission of light particles from hot and rotating CN. The model is applied to the decay of {sup 56}Ni* formed in the {sup 32}S+{sup 24}Mg reaction at two incident energies E{sub c.m.}=51.6 and 60.5 MeV. Both the IMFs and average TKE{sup lowbar} spectra are found to compare resonably well with the experimental data, favoring asymmetric mass distributions. The LPs' emission cross section is shown to depend strongly on the type of emitted particles and their multiplicities.

  15. Nuclear Astrophysics and Structure Studies Using Low-energy RI Beams at CRIB

    SciTech Connect

    Yamaguchi, H.; Hashimoto, T.; Hayakawa, S.; Binh, D. N.; Kahl, D.; Kubono, S.

    2010-05-12

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Using the RI beams at CRIB, Many measurements on proton and alpha resonance scatterings, (alpha,p) reactions, and others were peformed in recent years, mainly for studying astrophysical reactions and exotic nuclear structure. Among them, the results on the {sup 7}Be+p and {sup 7}Li+alpha resonance scatterings are presented.

  16. Nuclear Astrophysics and Structure Studies Using Low-energy RI Beams at CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Hashimoto, T.; Hayakawa, S.; Binh, D. N.; Kahl, D.; Kubono, S.

    2010-05-01

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Using the RI beams at CRIB, Many measurements on proton and alpha resonance scatterings, (α,p) reactions, and others were peformed in recent years, mainly for studying astrophysical reactions and exotic nuclear structure. Among them, the results on the 7Be+p and 7Li+α resonance scatterings are presented.

  17. Colorado School of Mines low energy nuclear physics project

    SciTech Connect

    Cecil, F.E.

    1991-01-02

    A major accomplishment of this project in the past year is the completion of a fairly comprehensive paper describing the survey of radiative capture reactions of protons on light nuclei at low energies. In addition we have completed a preliminary set of measurements of (d,p)/(d,{alpha}) cross section ratios on the charge symmetric nuclei {sup 6}Li and {sup 10}B as a test of the Oppenheimer-Phillips effect. While the {sup 6}Li data remain inconclusive, the {sup 10}B data show solid evidence for the Oppenheimer-Phillips enhancement of the (d,p) reaction relative to the (d,{alpha}) reaction for deuteron bombarding energies below about 100 keV. We have continued our investigation of fusion reaction products from deuterium-metal systems at room temperatures with the startling observation of intense burst of energetic charged particles from deuterium gas loaded thin titaium foils subject to non-equilibrium thermal and electrical conditions. We have completed two projects involving the application of the low energy particle accelerator to material science problems; firstly a study of the transformation of crystalline to amorphous Fe-Zr systems by proton irradiation and secondly the effects of ion bombardment on the critical temperature of YBCO high-temperature superconductors. Finally we have made progress in several instrumentation projects which will be used in some of the up-coming measurements of nuclear cross sections at very low energies.

  18. Analysis of the H(2)(+) with H(2) reaction using electron nuclear dynamics

    NASA Astrophysics Data System (ADS)

    Oreiro, Juan J. G.

    The END formalism addresses the solution of the time- dependent Schrodinger equation, treating both electrons and nuclei simultaneously. It differs from the other traditional fully quantum mechanical time-dependent methods in that it does not require a potential energy surface (PES) to carry the nuclear motion. The interaction between electronic and nuclear motion is, therefore, obtained in a transparent way, not relying on PES gradients to obtain the coupling between electrons and nuclei. We analyze the H2+ + H2 reaction at energies below 4 eV using different approximations and basis sets. Other than the choice of initial conditions, form of wave function, and basis set, no constraints are imposed on the system evolution. The nuclei are treated in the classical limit, and the electronic part is described by a single determinantal, unrestricted wave function. We obtain properties, such as Mulliken populations, transition probabilities, and cross-sections, from the resulting trajectories. These results are compared with other current theoretical approaches, and with experimental values. The relevance of the electron- nuclear coupling is estimated by comparing the END trajectories with molecular dynamics calculations for selected initial conditions in different basis sets.

  19. Alpha-induced reaction studies using low-energy RI beams at CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Kahl, D.; Hu, J.; Kubono, S.; Hayakawa, S.; Hashimoto, T.

    2012-11-01

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Studies on proton and alpha resonance scatterings, (α, p) reactions, and other types of measurements (β-decay lifetimes etc.) have been performed using RI beams at CRIB, motivated by interests on astrophysical reactions and exotic nuclear structure. Among the studies at CRIB, the measurement of 7Li+α/7Be+α resonant scatterings are presented.

  20. Alpha-induced reaction studies using low-energy RI beams at CRIB

    SciTech Connect

    Yamaguchi, H.; Kahl, D.; Hu, J.; Kubono, S.; Hayakawa, S.; Hashimoto, T.

    2012-11-12

    CRIB (CNS Radioactive Ion Beam separator) is a low-energy RI beam separator at the Center for Nuclear Study (CNS) of the University of Tokyo. Studies on proton and alpha resonance scatterings, ({alpha}, p) reactions, and other types of measurements ({beta}-decay lifetimes etc.) have been performed using RI beams at CRIB, motivated by interests on astrophysical reactions and exotic nuclear structure. Among the studies at CRIB, the measurement of {sup 7}Li+{alpha}/{sup 7}Be+{alpha} resonant scatterings are presented.

  1. Generation-IV Nuclear Energy Systems

    NASA Astrophysics Data System (ADS)

    McFarlane, Harold

    2008-05-01

    Nuclear power technology has evolved through roughly three generations of system designs: a first generation of prototypes and first-of-a-kind units implemented during the period 1950 to 1970; a second generation of industrial power plants built from 1970 to the turn of the century, most of which are still in operation today; and a third generation of evolutionary advanced reactors which began being built by the turn of the 20^th century, usually called Generation III or III+, which incorporate technical lessons learned through more than 12,000 reactor-years of operation. The Generation IV International Forum (GIF) is a cooperative international endeavor to develop advanced nuclear energy systems in response to the social, environmental and economic requirements of the 21^st century. Six Generation IV systems under development by GIF promise to enhance the future contribution and benefits of nuclear energy. All Generation IV systems aim at performance improvement, new applications of nuclear energy, and/or more sustainable approaches to the management of nuclear materials. High-temperature systems offer the possibility of efficient process heat applications and eventually hydrogen production. Enhanced sustainability is achieved primarily through adoption of a closed fuel cycle with reprocessing and recycling of plutonium, uranium and minor actinides using fast reactors. This approach provides significant reduction in waste generation and uranium resource requirements.

  2. Realizing the potential of nuclear energy. [Monograph

    SciTech Connect

    Walske, C.

    1982-01-01

    The future of nuclear power, just as the future of America, can be viewed with optimism. There is hope in America's record of overcoming obstacles, but growth is essential for that hope to be realized. Despite the downturn in energy demand made possible by conservation, we will need a 35% growth in total energy for new workers and production. Electricity generated by nuclear or coal can make US production more cost-competitive, and it can power mass-transit systems, electric heat pumps, and communications and information systems. Changes in electricity and gross national product (GNP) have been more closely in step since 1973 than have total energy and GNP. The nuclear power units now under construction will add 80,000 megawatts to the 56,000 now on line. It is important to note that, while utilities are cancelling plans for nuclear plants, they aren't ordering new coal plants, which shows the impact of the high cost of money. Interest rates must come down and public-relations efforts to sell electricity must improve to change the situation. Although capital shortages are real, waste disposal is a problem of perception that was politically induced because the government failed to provide a demonstration of safety as the French are doing. Streamlined regulatory and insurance procedures can help to justify optimism in the nuclear option. 4 figures. (DCK)

  3. An approach to a self-consistent nuclear energy system

    SciTech Connect

    Fujii-e, Yoichi ); Arie, Kazuo; Endo, Hiroshi )

    1992-01-01

    A nuclear energy system should provide a stable supply of energy without endangering the environment or humans. If there is fear about exhausting world energy resources, accumulating radionuclides, and nuclear reactor safety, tension is created in human society. Nuclear energy systems of the future should be able to eliminate fear from people's minds. In other words, the whole system, including the nuclear fuel cycle, should be self-consistent. This is the ultimate goal of nuclear energy. If it can be realized, public acceptance of nuclear energy will increase significantly. In a self-consistent nuclear energy system, misunderstandings between experts on nuclear energy and the public should be minimized. The way to achieve this goal is to explain using simple logic. This paper proposes specific targets for self-consistent nuclear energy systems and shows that the fast breeder reactor (FBR) lies on the route to attaining the final goal.

  4. 78 FR 49726 - International Framework for Nuclear Energy Cooperation Finance/Regulatory/Energy Planning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-15

    ... International Trade Administration International Framework for Nuclear Energy Cooperation Finance/ Regulatory... International Framework for Nuclear Energy Cooperation (IFNEC)--to organize participation by representatives of... power projects, including national energy planning authorities, nuclear regulatory institutions,...

  5. Experimental cross-sections for proton-induced nuclear reactions on natMo

    NASA Astrophysics Data System (ADS)

    Červenák, Jaroslav; Lebeda, Ondřej

    2016-08-01

    In the framework of the Co-ordinated Research Project of the IAEA, we measured in detail cross-sections of the nuclear reactions natMo(p,x)93gTc, 93mTc, 93m+gTc, 94gTc, 94mTc, 95gTc, 95mTc, 96m+gTc, 97mTc, 99mTc, 90Mo, 93mMo, 99Mo, 88gNb, 88mNb, 89gNb, 89mNb, 90m+gNb, 90m+gNbcum, 91mNb, 92mNb, 95gNb, 95mNb, 95m+gNb, 96Nb, 97m+gNb, 88m+gZrcum and 89m+gZrcum in the energy range of 6.9-35.8 MeV. The data for formation of 97mTc, 88gNb, 88mNb and 89mNb are reported for the first time. The obtained results were compared to the prediction of the nuclear reaction model code TALYS adopted from the TENDL-2015 library and to the previously published cross-sections. The thick target yields for all the radionuclides were calculated from the measured data. We suggest recommended cross-sections and thick target yields for the 100Mo(p,2n)99mTc, 100Mo(p,x)99Mo and natMo(p,x)96m+gTc nuclear reactions deduced from the selected experimental data.

  6. Thermal Tests of Target Materials for Nuclear Reaction-Based Interrogation Sources

    SciTech Connect

    Provencio, P. P.; Doyle, B. L.; McDaniel, F. D.; Antolak, A. J.; Morse, D. H.

    2009-03-10

    Compact active interrogation sources are being developed that use low-energy (kilovolt) nuclear reactions to produce high-energy (megavolt) neutrons or gamma-rays. We are evaluating target materials for these interrogation sources by performing rapid thermal load and high power density tests that reach conditions expected during source operation. Following the tests, the targets are analyzed with low and high resolution microscopes to assess whether any physical or structural damage has occurred. This paper presents results of the examinations of LiF, Li{sub 2}O, LiNbO{sub 3}, CaF{sub 2}, B{sub 4}C, and LaB{sub 6} target materials following rapid thermal and electron beam heating tests.

  7. Nuclear Structure of 99Mo from the (t,p) Reaction

    NASA Astrophysics Data System (ADS)

    Rahman, M. A.; Chowdhury, M. S.

    The 97Mo(t,p)99Mo reaction has been studied with the triton beam energy of 12 MeV obtained from tandem Van de Graaff accelerator at the Atomic Weapon Research Establishment, Aldermaston. Proton spectra were obtained at 12 different angles from 5° to 87.5° at an interval of 7.5° and were detected in nuclear emulsion plates. Angular distributions for transitions to 46 levels in the energy range from 0 to 2.054 MeV have been measured. Absolute differential cross-sections for the levels have been measured. The experimental angular distributions are compared with the distorted-wave Born approximation calculations (DWBA) to determine L and Jπ values. The present results are compared with the previous experimental results and model predictions.

  8. A nuclear fragmentation energy deposition model

    NASA Technical Reports Server (NTRS)

    Ngo, D. M.; Wilson, J. W.; Fogarty, T. N.; Buck, W. W.; Townsend, L. W. (Principal Investigator)

    1991-01-01

    A formalism for target fragment transport is presented with application to energy loss spectra in thin silicon devices. A nuclear data base is recommended that agrees well with the measurements of McNulty et al. using surface barrier detectors. High-energy events observed by McNulty et al., which are not predicted by intranuclear cascade models, are well represented by the present work.

  9. NSTA Conducts Nuclear Energy Survey for AIF

    ERIC Educational Resources Information Center

    Science Teacher, 1972

    1972-01-01

    A survey conducted to determine teacher's instructional resources, methods, materials, and attitudes toward various uses of nuclear energy resulted in nearly one thousand science teachers throughout the nation responding. Results of survey are presented and five recommendations for action are made. (DF)

  10. Stamps Tell the Story of Nuclear Energy.

    ERIC Educational Resources Information Center

    Angelo, Joseph A., Jr.

    This document provides a summary history of the individual scientists principally responsible for the development of nuclear physics and a survey of modern utilization of atomic energy. Identified throughout the booklet are postage stamps illustrating each individual and topic discussed. (SL)

  11. Towards the Universal Nuclear Energy Density Functional

    SciTech Connect

    Stoitsov, Mario; More, J.; Nazarewicz, Witold; Pei, Junchen; Sarich, J.; Schunck, Nicolas F; Staszczak, A.; Wild, S.

    2009-01-01

    The UNEDF SciDAC project to develop and optimize the energy density functional for atomic nuclei using state-of-the-art computational infrastructure is briefly described. The ultimate goal is to replace current phenomenological models of the nucleus with a well-founded microscopic theory with minimal uncertainties, capable of describing nuclear data and extrapolating to unknown regions.

  12. Nuclear Energy Technologies for Hydrogen Production

    SciTech Connect

    Yildiz, Bilge; Kazimi, Mujid S.

    2004-07-01

    Nuclear energy can be used as the primary thermal energy source in centralized hydrogen production through several methods to address the expected demand for hydrogen. The hydrogen production technologies that the nuclear reactors can be coupled to are such as high temperature thermochemical and hybrid processes, water electrolysis, and high-temperature steam electrolysis. Energy efficiency and use of clean technologies is important to meet the increasing energy demand in a climate friendly manner. High operating temperatures are needed for more efficient thermochemical and electrochemical hydrogen production using nuclear energy. Therefore, high temperature reactors, such as the gas cooled, molten salt cooled and liquid metal cooled reactor technologies, are the candidates for use in hydrogen production. Among these alternatives, high temperature steam electrolysis (HTSE) coupled to an advanced gas reactor cooled by supercritical CO{sub 2} (S-CO{sub 2}) and a direct S-CO{sub 2} power conversion cycle has the potential to provide higher energy efficiency at lower temperature range than the other alternatives. (authors)

  13. Exclusive CHIPS-TPT algorithms for simulation of neutron-nuclear reactions

    NASA Astrophysics Data System (ADS)

    Kosov, Mikhail; Savin, Dmitriy

    2016-09-01

    The CHIPS-TPT physics library for simulation of neutron-nuclear reactions on the new exclusive level is being developed in CFAR VNIIA. The exclusive modeling conserves energy, momentum and quantum numbers in each neutron-nuclear interaction. The CHIPS-TPT algorithms are based on the exclusive CHIPS library, which is compatible with Geant4. Special CHIPS-TPT physics lists in the Geant4 format are provided. The calculation time for an exclusive CHIPS-TPT simulation is comparable to the time of the corresponding inclusive Geant4-HP simulation and much faster for mono-isotopic simulations. In addition to the reduction of the deposited energy fluctuations, which is a consequence of the energy conservation, the CHIPS-TPT libraries provide a possibility of simulation of the secondary particles correlation, e.g. secondary gammas or n-γ correlations, and of the Doppler broadening of the γ-lines in the simulated spectra, which can be measured by germanium detectors.

  14. Application of Nuclear Energy to Bitumen Upgrading and Biomass Conversion

    SciTech Connect

    Mamoru Numata; Yasushi Fujimura; Takayuki Amaya; Masao Hori

    2006-07-01

    Key drivers for the increasing use of nuclear energy are the need to mitigate global warming and the requirement for energy security. Nuclear energy can be applied not only to generate electricity but also as a heat source. Moreover, nuclear energy can be applied for hydrogen as well as water production. The application of nuclear energy to oil processing and biomass production is studied in this paper. (authors)

  15. Children's reactions to the threat of nuclear plant accidents.

    PubMed

    Schwebel, M; Schwebel, B

    1981-04-01

    In the wake of Three Mile Island nuclear plant accident, questionnaire and interview responses of children in elementary and secondary schools revealed their perceptions of the dangers entailed in the continued use of nuclear reactors. Results are compared with a parallel study conducted close to 20 years ago, and implications for mental health are examined. PMID:7223871

  16. Manufactured Doubt: The Campaign Against Nuclear Energy

    NASA Astrophysics Data System (ADS)

    Rogers, N. L.

    2012-12-01

    Nuclear electricity is a CO2 free technology with a proven track record of large scale commercial deployment. For example, France generates 78% of its electrical power with nuclear plants. France has the lowest pre-tax cost of electricity in Europe at 4.75 eurocents per KWH and France is the world's largest exporter of electricity. There are large world reserves of uranium sufficient for hundreds of years, even without breeder technology. Additionally, thorium, another radioactive mineral is in even more plentiful supply. Although present-day nuclear technology has proven to be safe and reliable, waiting in the wings is new generation technology that promises great improvements in both safety and cost. Yet, there has been a calculated and sophisticated campaign in the later part of the 20th century to create doubt and fear concerning nuclear power. In the United States this campaign has essentially destroyed the nuclear industry. No new plants have been commissioned for decades. Leadership in the nuclear power field has been ceded to other countries. The great paradox is that the very organizations that express great alarm concerning CO2 emissions are the same organizations that led the campaign against nuclear power decades ago. Representatives of these organizations will say privately that they are taking a new look at nuclear power, but no major organization has reversed course and become a supporter of nuclear power. To do so would involve a loss of face and create doubts concerning the credibility of the organization. As recently as 2001 environmentalist lobbyists made great efforts to ensure that no credit could be given for nuclear power under the Kyoto accords and the associated clean development mechanism. They succeeded and nuclear power receives unfavorable treatment under the Kyoto accords even though it is a proven solution for reducing CO2 emissions. The technique used to destroy nuclear energy as a viable alternative in the United States had two

  17. Compact Detection System for High Sensitivity Hydrogen Profiling of Materials by Nuclear Reaction Analysis

    SciTech Connect

    Marble, Daniel Keith; Urban, Ben; Pacheco, Jose

    2009-03-10

    Hydrogen is a ubiquitous contaminant that is known to have dramatic effects on the electrical, chemical, and mechanical properties of many types of materials in even minute quantities. Thus, the detection of hydrogen in materials is of major importance. Nuclear Reaction Analysis (NRA) is a powerful technique for nondestructive profiling hydrogen in materials. However, NRA has found only limited use in many applications because of poor sensitivity due to cosmic ray background (CSRB). Most attempts to eliminate CSRB to achieve ppm detection levels using higher energy nuclear reactions or tons of passive shielding are not compatible with commercial ion beam analysis space and equipment requirements Zimmerman, et al. have previously reported upon a coincidence detector that meets IBA space requirements and reduces the cosmic ray background, but the detector suffers from lower detection efficiency and small sample size. We have replaced the BGO well detector in the Zimmerman coincidence detection scheme with a larger Nal well detector and used faster timing electronics to produce a detector that can handle larger samples with higher detection efficiency, and still eliminate cosmic ray background.

  18. Symmetry energy of dilute warm nuclear matter.

    PubMed

    Natowitz, J B; Röpke, G; Typel, S; Blaschke, D; Bonasera, A; Hagel, K; Klähn, T; Kowalski, S; Qin, L; Shlomo, S; Wada, R; Wolter, H H

    2010-05-21

    The symmetry energy of nuclear matter is a fundamental ingredient in the investigation of exotic nuclei, heavy-ion collisions, and astrophysical phenomena. New data from heavy-ion collisions can be used to extract the free symmetry energy and the internal symmetry energy at subsaturation densities and temperatures below 10 MeV. Conventional theoretical calculations of the symmetry energy based on mean-field approaches fail to give the correct low-temperature, low-density limit that is governed by correlations, in particular, by the appearance of bound states. A recently developed quantum-statistical approach that takes the formation of clusters into account predicts symmetry energies that are in very good agreement with the experimental data. A consistent description of the symmetry energy is given that joins the correct low-density limit with quasiparticle approaches valid near the saturation density.

  19. 75 FR 16524 - FirstEnergy Nuclear Operating Company, Perry Nuclear Power Plant; Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-01

    ... COMMISSION FirstEnergy Nuclear Operating Company, Perry Nuclear Power Plant; Exemption 1.0 Background FirstEnergy Nuclear Operating Company (FENOC, the licensee) is the holder of Facility Operating License No... compliance date (Reference: June 4, 2009, letter from R. W. Borchardt, NRC, to M. S. Fertel, Nuclear...

  20. 75 FR 38147 - FirstEnergy Nuclear Operating Company; Davis-Besse Nuclear Power Station; Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION FirstEnergy Nuclear Operating Company; Davis-Besse Nuclear Power Station; Exemption 1.0 Background FirstEnergy Nuclear Operating Company (FENOC, the licensee) is the holder of Facility Operating...

  1. 75 FR 80549 - FirstEnergy Nuclear Operating Company, Davis-Besse Nuclear Power Station; Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-22

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION FirstEnergy Nuclear Operating Company, Davis-Besse Nuclear Power Station; Exemption 1.0 Background FirstEnergy Nuclear Operating Company (FENOC, the licensee) is the holder of Facility Operating...

  2. On the implementation of a chain nuclear reaction of thermonuclear fusion on the basis of the p+11B process

    NASA Astrophysics Data System (ADS)

    Belyaev, V. S.; Krainov, V. P.; Zagreev, B. V.; Matafonov, A. P.

    2015-07-01

    Various theoretical and experimental schemes for implementing a thermonuclear reactor on the basis of the p+11B reaction are considered. They include beam collisions, fusion in degenerate plasmas, ignition upon plasma acceleration by ponderomotive forces, and the irradiation of a solid-state target from 11B with a proton beam under conditions of a Coulomb explosion of hydrogen microdrops. The possibility of employing ultra-short high-intensity laser pulses to initiate the p+11B reaction under conditions far from thermodynamic equilibrium is discussed. This and some other weakly radioactive thermonuclear reactions are promising owing to their ecological cleanness—there are virtually no neutrons among fusion products. Nuclear reactions that follow the p+11B reaction may generate high-energy protons, sustaining a chain reaction, and this is an advantage of the p+11B option. The approach used also makes it possible to study nuclear reactions under conditions close to those in the early Universe or in the interior of stars.

  3. On the possibility of negative activation energies in bimolecular reactions

    NASA Technical Reports Server (NTRS)

    Jaffe, R. L.

    1978-01-01

    The temperature dependence of the rate constants for model reacting systems was studied to understand some recent experimental measurements which imply the existence of negative activation energies. A collision theory model and classical trajectory calculations are used to demonstrate that the reaction probability can vary inversely with collision energy for bimolecular reactions occurring on attractive potential energy surfaces. However, this is not a sufficient condition to ensure that the rate constant has a negative temperature dependence. On the basis of these calculations, it seems unlikely that a true bimolecular reaction between neutral molecules will have a negative activation energy.

  4. International nuclear societies council vision for the second fifty years of nuclear energy

    SciTech Connect

    Hatcher, S.R.

    1994-12-31

    A vision of the future should be in the context of ongoing social and technological development Perhaps the most compelling moral and ethical issue facing the world at the close of the 20th Century is to help the peoples of the poorer countries in their struggle for a reasonable quality of life, while at the saw time they face a dramatic increase in their population. Despite improvements in the efficiency of energy use, world energy demand will continue to grow significantly, driven by: (1) an inevitable population increase; (2) the communications revolution, which will generate global aspirations for a better quality of life; (3) the need to generate wealth to address the new level of aspirations; and (4) environmental protection as a cornerstone of sustainable development. The vision of abundant energy in the service of mankind came a step closer to realisation following the discoveries of the properties of the nucleus in the 1930`s. The achievement of a sustained chain fission reaction in 1942 led to the development of nuclear fission into an electrical energy system that now supplies 7% of the world`s energy. The earth`s resources of uranium and thorium for fission and deuterium for fusion provided a virtually inexhaustible rarely of fuel. Looking at the needs of the world over the next 50 years, one can visualise that an even more important contribution will be demanded of nuclear energy.

  5. Extension of PENELOPE to protons: Simulation of nuclear reactions and benchmark with Geant4

    SciTech Connect

    Sterpin, E.; Sorriaux, J.; Vynckier, S.

    2013-11-15

    Purpose: Describing the implementation of nuclear reactions in the extension of the Monte Carlo code (MC) PENELOPE to protons (PENH) and benchmarking with Geant4.Methods: PENH is based on mixed-simulation mechanics for both elastic and inelastic electromagnetic collisions (EM). The adopted differential cross sections for EM elastic collisions are calculated using the eikonal approximation with the Dirac–Hartree–Fock–Slater atomic potential. Cross sections for EM inelastic collisions are computed within the relativistic Born approximation, using the Sternheimer–Liljequist model of the generalized oscillator strength. Nuclear elastic and inelastic collisions were simulated using explicitly the scattering analysis interactive dialin database for {sup 1}H and ICRU 63 data for {sup 12}C, {sup 14}N, {sup 16}O, {sup 31}P, and {sup 40}Ca. Secondary protons, alphas, and deuterons were all simulated as protons, with the energy adapted to ensure consistent range. Prompt gamma emission can also be simulated upon user request. Simulations were performed in a water phantom with nuclear interactions switched off or on and integral depth–dose distributions were compared. Binary-cascade and precompound models were used for Geant4. Initial energies of 100 and 250 MeV were considered. For cases with no nuclear interactions simulated, additional simulations in a water phantom with tight resolution (1 mm in all directions) were performed with FLUKA. Finally, integral depth–dose distributions for a 250 MeV energy were computed with Geant4 and PENH in a homogeneous phantom with, first, ICRU striated muscle and, second, ICRU compact bone.Results: For simulations with EM collisions only, integral depth–dose distributions were within 1%/1 mm for doses higher than 10% of the Bragg-peak dose. For central-axis depth–dose and lateral profiles in a phantom with tight resolution, there are significant deviations between Geant4 and PENH (up to 60%/1 cm for depth

  6. Decoding the nuclear genome using nuclear binding and fusion energies

    NASA Astrophysics Data System (ADS)

    Yablon, Jay R.

    2015-04-01

    In several publications the author has presented the theory that protons and neutrons and other baryons are the chromo-magnetic monopoles of Yang-Mills gauge theory and used that to deduce the up and down current quark masses from the tightly-known Q = 0 empirical electron mass and the neutron minus proton mass difference with commensurately high precision. This is then used as a springboard to closely fit a wide range of empirical nuclear binding and fusion energy data and to obtain the proton and neutron masses themselves within all experimental errors. This presentation will systematically pull all of this together and a) establishes that this way of defining current quark masses constitutes a valid measurement scheme, b) lays out the empirical support for this theory via observed nuclear binding and fusion energies as well as the proton and neutron masses themselves, c) solidifies the interface used to connect the theory to these empirical results and uncovers a mixing between the up and down current quark masses, and d) presents clearly how and why the underlying theory is very conservative, being no more and no less than a deductive mathematical synthesis of Maxwell's classical theory with both the electric and magnetic field equations merged into one, Yang-Mills gauge theory, Dirac fermion theory, the Fermi-Dirac-Pauli Exclusion Principle, and to get from classical chromodynamics to QCD, Feynman path integration.

  7. Summary Report of the Workshop on The Experimental Nuclear Reaction Data Database

    SciTech Connect

    Semkova, V.; Pritychenko, B.

    2014-10-10

    The Workshop on the Experimental Nuclear Reaction Data Database (EXFOR) was held at IAEA Headquarters in Vienna from 6 to 10 October 2014. The workshop was organized to discuss various aspects of the EXFOR compilation process including compilation rules, different techniques for nuclear reaction data measurements, software developments, etc. A summary of the presentations and discussions that took place during the workshop is reported here.

  8. Heuristic control of kinetic energy in dynamic reaction coordinate calculations.

    PubMed

    Hellweg, Arnim

    2013-08-01

    For the understanding and prediction of chemical reactions, detailed knowledge of the minimum energy path between reactants and transition state is of utmost importance. Stewart et al. (J. Comput. Chem. 1987, 8, 1117) proposed the usage of molecular trajectories calculated from Newton's equations of motion for an efficient reaction path following. Two operational modes are possible thereby: intrinsic (IRC) and dynamic reaction coordinate calculations (DRC). The technical difference between these modes is that in an IRC calculation the kinetic energy of the nuclei is quenched while the total energy is conserved in DRC calculations. In this work, a heuristic control methodology of atomic kinetic energies in DRC calculations using fuzzy logic is proposed. A diversified test set of 10 reactions has been collected to examine the performance of this approach. Fuzzy rule-based models are found to be a convenient way to make the determination of accessible paths of chemical reactions computationally efficient.

  9. Computed potential energy surfaces for chemical reactions

    NASA Technical Reports Server (NTRS)

    Heinemann, K.; Walch, Stephen P.

    1992-01-01

    The work on the NH + NO system which was described in the last progress report was written up and a draft of the manuscript is included in the appendix. The appendix also contains a draft of a manuscript on an Ar + H + H surface. New work which was completed in the last six months includes the following: (1) calculations on the (1)CH2 + H2O, H2 + HCOH, and H2 + H2CO product channels in the CH3 + OH reaction; (2) calculations for the NH2 + O reaction; (3) calculations for the CH3 + O2 reaction; and (4) calculations for CH3O and the two decomposition channels--CH2OH and H + H2CO. Detailed descriptions of this work will be given in manuscripts; however, brief descriptions of the CH3 + OH and CH3 + O2 projects are given.

  10. Radiation chemistry for modern nuclear energy development

    NASA Astrophysics Data System (ADS)

    Chmielewski, Andrzej G.; Szołucha, Monika M.

    2016-07-01

    Radiation chemistry plays a significant role in modern nuclear energy development. Pioneering research in nuclear science, for example the development of generation IV nuclear reactors, cannot be pursued without chemical solutions. Present issues related to light water reactors concern radiolysis of water in the primary circuit; long-term storage of spent nuclear fuel; radiation effects on cables and wire insulation, and on ion exchangers used for water purification; as well as the procedures of radioactive waste reprocessing and storage. Radiation effects on materials and enhanced corrosion are crucial in current (II/III/III+) and future (IV) generation reactors, and in waste management, deep geological disposal and spent fuel reprocessing. The new generation of reactors (III+ and IV) impose new challenges for radiation chemists due to their new conditions of operation and the usage of new types of coolant. In the case of the supercritical water-cooled reactor (SCWR), water chemistry control may be the key factor in preventing corrosion of reactor structural materials. This paper mainly focuses on radiation effects on long-term performance and safety in the development of nuclear power plants.

  11. Converting Energy to Medical Progress [Nuclear Medicine

    DOE R&D Accomplishments Database

    2001-04-01

    For over 50 years the Office of Biological and Environmental Research (BER) of the United States Department of Energy (DOE) has been investing to advance environmental and biomedical knowledge connected to energy. The BER Medical Sciences program fosters research to develop beneficial applications of nuclear technologies for medical diagnosis and treatment of many diseases. Today, nuclear medicine helps millions of patients annually in the United States. Nearly every nuclear medicine scan or test used today was made possible by past BER-funded research on radiotracers, radiation detection devices, gamma cameras, PET and SPECT scanners, and computer science. The heart of biological research within BER has always been the pursuit of improved human health. The nuclear medicine of tomorrow will depend greatly on today's BER-supported research, particularly in the discovery of radiopharmaceuticals that seek specific molecular and genetic targets, the design of advanced scanners needed to create meaningful images with these future radiotracers, and the promise of new radiopharmaceutical treatments for cancers and genetic diseases.

  12. Converting energy to medical progress [nuclear medicine

    SciTech Connect

    2001-04-01

    For over 50 years the Office of Biological and Environmental Research (BER) of the United States Department of Energy (DOE) has been investing to advance environmental and biomedical knowledge connected to energy. The BER Medical Sciences program fosters research to develop beneficial applications of nuclear technologies for medical diagnosis and treatment of many diseases. Today, nuclear medicine helps millions of patients annually in the United States. Nearly every nuclear medicine scan or test used today was made possible by past BER-funded research on radiotracers, radiation detection devices, gamma cameras, PET and SPECT scanners, and computer science. The heart of biological research within BER has always been the pursuit of improved human health. The nuclear medicine of tomorrow will depend greatly on today's BER-supported research, particularly in the discovery of radiopharmaceuticals that seek specific molecular and genetic targets, the design of advanced scanners needed to create meaningful images with these future radiotracers, and the promise of new radiopharmaceutical treatments for cancers and genetic diseases.

  13. Studying astrophysical reactions with low-energy RI beams at CRIB

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Kahl, D.; Hayakawa, S.; Sakaguchi, Y.; Wakabayashi, Y.; Hashimoto, T.; Cherubini, S.; Gulino, M.; Spitaleri, C.; Rapisarda, G. G.; La Cognata, M.; Lamia, L.; Romano, S.; Kubono, S.; Iwasa, N.; Teranishi, T.; Kawabata, T.; Kwon, Y. K.; Binh, D. N.; Khiem, L. H.; Duy, N. N.; Kato, S.; Komatsubara, T.; Coc, A.; De Sereville, N.; Hammache, F.; Kiss, G.; Bishop, S.

    2016-05-01

    Studies on nuclear astrophysics, nuclear structure, and other interests have been performed using the radioactive-isotope (RI) beams at the low-energy RI beam separator CRIB, operated by Center for Nuclear Study (CNS), the University of Tokyo. A typical measurement performed at CRIB is the elastic resonant scattering with the inverse kinematics. One recent experiment was on the α resonant scattering with 7Li and 7Be beams. This study is related to the astrophysical 7Li/7Be(α,γ) reactions, important at hot p-p chain and νp-process in supernovae. There have also been measurements based on other experimental methods. The first THM measurement using an RI beam has been performed at CRIB, to study the 18F(p, α)15O reaction at astrophysical energies via the three body reaction 2H(18F, α15O)n. The 18F(p, α) 15O reaction rate is crucial to understand the 511-keV γ-ray production in nova explosion phenomena, and we successfully evaluated the reaction cross section at novae temperature and below experimentally for the first time.

  14. Study of components and statistical reaction mechanism in simulation of nuclear process for optimized production of {sup 64}Cu and {sup 67}Ga medical radioisotopes using TALYS, EMPIRE and LISE++ nuclear reaction and evaporation codes

    SciTech Connect

    Nasrabadi, M. N. Sepiani, M.

    2015-03-30

    Production of medical radioisotopes is one of the most important tasks in the field of nuclear technology. These radioactive isotopes are mainly produced through variety nuclear process. In this research, excitation functions and nuclear reaction mechanisms are studied for simulation of production of these radioisotopes in the TALYS, EMPIRE and LISE++ reaction codes, then parameters and different models of nuclear level density as one of the most important components in statistical reaction models are adjusted for optimum production of desired radioactive yields.

  15. Nuclear Reaction Models Responsible for Simulation of Neutron-induced Soft Errors in Microelectronics

    SciTech Connect

    Watanabe, Y. Abe, S.

    2014-06-15

    Terrestrial neutron-induced soft errors in MOSFETs from a 65 nm down to a 25 nm design rule are analyzed by means of multi-scale Monte Carlo simulation using the PHITS-HyENEXSS code system. Nuclear reaction models implemented in PHITS code are validated by comparisons with experimental data. From the analysis of calculated soft error rates, it is clarified that secondary He and H ions provide a major impact on soft errors with decreasing critical charge. It is also found that the high energy component from 10 MeV up to several hundreds of MeV in secondary cosmic-ray neutrons has the most significant source of soft errors regardless of design rule.

  16. Feasibility study of nuclear transmutation by negative muon capture reaction using the PHITS code

    NASA Astrophysics Data System (ADS)

    Abe, Shin-ichiro; Sato, Tatsuhiko

    2016-06-01

    Feasibility of nuclear transmutation of fission products in high-level radioactive waste by negative muon capture reaction is investigated using the Particle and Heave Ion Transport code System (PHITS). It is found that about 80 % of stopped negative muons contribute to transmute target nuclide into stable or short-lived nuclide in the case of 135Cs, which is one of the most important nuclide in the transmutation. The simulation result also indicates that the position of transmutation is controllable by changing the energy of incident negative muon. Based on our simulation, it takes approximately 8.5 × 108years to transmute 500 g of 135Cs by negative muon beam with the highest intensity currently available.

  17. Analysis of the Nuclear Structure of 186 Re Using Neutron-Induced Reactions

    NASA Astrophysics Data System (ADS)

    Matters, David; McClory, John; Carroll, James; Chiara, Chris; Fotiades, Nikolaos; Devlin, Matt; Nelson, Ron O.

    2015-04-01

    Evaluated nuclear structure data for 186 Re identifies the majority of spin-parity assignments as tentative, with approximate values associated with the energies of several levels and transitions. In particular, the absence of known transitions that feed the Jπ =8+ isomer motivates their discovery, which would have astrophysical implications and a potential application in the development of an isomer power source. Using the GErmanium Array for Neutron Induced Excitations (GEANIE) spectrometer at the Los Alamos Neutron Science Center (LANSCE) Weapons Neutron Research (WNR) facility, the (n,2n γ) and (n,n' γ) reactions in a 99.52% enriched 187 Re target were used to measure γ-ray excitation functions in 186 Re and 187 Re, respectively. A preliminary analysis of the data obtained from the experiment reveals several new transitions in 186 Re and 187 Re.

  18. Code System to Calculate Nuclear Reaction Cross Sections by Evaporation Model.

    2000-11-27

    Version: 00 Both STAPRE and STAPREF are included in this package. STAPRE calculates energy-averaged cross sections for nuclear reactions with emission of particles and gamma rays and fission. The models employed are the evaporation model with inclusion of pre-equilibrium decay and a gamma-ray cascade model. Angular momentum and parity conservation are accounted for. Major improvement in the 1976 STAPRE program relates to level density approach, implemented in subroutine ZSTDE. Generalized superfluid model is incorporated, boltzman-gasmore » modeling of intrinsic state density and semi-empirical modeling of a few-quasiparticle effects in total level density at equilibrium and saddle deformations of actinide nuclei. In addition to the activation cross sections, particle and gamma-ray production spectra are calculated. Isomeric state populations and production cross sections for gamma rays from low excited levels are obtained, too. For fission a single or a double humped barrier may be chosen.« less

  19. Nuclear Energy Innovation Workshops. Executive Summary

    SciTech Connect

    Allen, Todd; Jackson, John; Hildebrandt, Phil; Baker, Suzy

    2015-06-01

    The nuclear energy innovation workshops were organized and conducted by INL on March 2-4, 2015 at the five NUC universities and Boise State University. The output from these workshops is summarized with particular attention to final summaries that were provided by technical leads at each of the workshops. The current revision includes 3-4 punctuation corrections and a correction of the month of release from May to June.

  20. PHASE-OTI: A pre-equilibrium model code for nuclear reactions calculations

    NASA Astrophysics Data System (ADS)

    Elmaghraby, Elsayed K.

    2009-09-01

    The present work focuses on a pre-equilibrium nuclear reaction code (based on the one, two and infinity hypothesis of pre-equilibrium nuclear reactions). In the PHASE-OTI code, pre-equilibrium decays are assumed to be single nucleon emissions, and the statistical probabilities come from the independence of nuclei decay. The code has proved to be a good tool to provide predictions of energy-differential cross sections. The probability of emission was calculated statistically using bases of hybrid model and exciton model. However, more precise depletion factors were used in the calculations. The present calculations were restricted to nucleon-nucleon interactions and one nucleon emission. Program summaryProgram title: PHASE-OTI Catalogue identifier: AEDN_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDN_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 5858 No. of bytes in distributed program, including test data, etc.: 149 405 Distribution format: tar.gz Programming language: Fortran 77 Computer: Pentium 4 and Centrino Duo Operating system: MS Windows RAM: 128 MB Classification: 17.12 Nature of problem: Calculation of the differential cross section for nucleon induced nuclear reaction in the framework of pre-equilibrium emission model. Solution method: Single neutron emission was treated by assuming occurrence of the reaction in successive steps. Each step is called phase because of the phase transition nature of the theory. The probability of emission was calculated statistically using bases of hybrid model [1] and exciton model [2]. However, more precise depletion factor was used in the calculations. Exciton configuration used in the code is that described in earlier work [3]. Restrictions: The program is restricted to single nucleon emission and nucleon

  1. Extracting nuclear sizes of medium to heavy nuclei from total reaction cross sections

    NASA Astrophysics Data System (ADS)

    Horiuchi, W.; Hatakeyama, S.; Ebata, S.; Suzuki, Y.

    2016-04-01

    Background: Proton and neutron radii are fundamental quantities of atomic nuclei. To study the sizes of short-lived unstable nuclei, there is a need for an alternative to electron scattering. Purpose: The recent paper by Horiuchi et al. [Phys. Rev. C 89, 011601(R) (2014)], 10.1103/PhysRevC.89.011601 proposed a possible way of extracting the matter and neutron-skin thickness of light- to medium-mass nuclei using total reaction cross section, σR. The analysis is extended to medium to heavy nuclei up to lead isotopes with due attention to Coulomb breakup contributions as well as density distributions improved by paring correlation. Methods: We formulate a quantitative calculation of σR based on the Glauber model including the Coulomb breakup. To substantiate the treatment of the Coulomb breakup, we also evaluate the Coulomb breakup cross section due to the electric dipole field in a canonical-basis-time-dependent-Hartree-Fock-Bogoliubov theory in the three-dimensional coordinate space. Results: We analyze σR's of 103 nuclei with Z =20 , 28, 40, 50, 70, and 82 incident on light targets, H,21, 4He, and 12C. Three kinds of Skyrme interactions are tested to generate those wave functions. To discuss possible uncertainty due to the Coulomb breakup, we examine its dependence on the target, the incident energy, and the Skyrme interaction. The proton is a most promising target for extracting the nuclear sizes as the Coulomb excitation can safely be neglected. We find that the so-called reaction radius, aR=√{σR/π } , for the proton target is very well approximated by a linear function of two variables, the matter radius and the skin thickness, in which three constants depend only on the incident energy. We quantify the accuracy of σR measurements needed to extract the nuclear sizes. Conclusions: The proton is the best target because, once the incident energy is set, its aR is very accurately determined by only the matter radius and neutron-skin thickness. If σR's at

  2. Theories of Variable Mass Particles and Low Energy Nuclear Phenomena

    NASA Astrophysics Data System (ADS)

    Davidson, Mark

    2014-02-01

    Variable particle masses have sometimes been invoked to explain observed anomalies in low energy nuclear reactions (LENR). Such behavior has never been observed directly, and is not considered possible in theoretical nuclear physics. Nevertheless, there are covariant off-mass-shell theories of relativistic particle dynamics, based on works by Fock, Stueckelberg, Feynman, Greenberger, Horwitz, and others. We review some of these and we also consider virtual particles that arise in conventional Feynman diagrams in relativistic field theories. Effective Lagrangian models incorporating variable mass particle theories might be useful in describing anomalous nuclear reactions by combining mass shifts together with resonant tunneling and other effects. A detailed model for resonant fusion in a deuterium molecule with off-shell deuterons and electrons is presented as an example. Experimental means of observing such off-shell behavior directly, if it exists, is proposed and described. Brief explanations for elemental transmutation and formation of micro-craters are also given, and an alternative mechanism for the mass shift in the Widom-Larsen theory is presented. If variable mass theories were to find experimental support from LENR, then they would undoubtedly have important implications for the foundations of quantum mechanics, and practical applications may arise.

  3. NUCLEAR REACTION AND STRUCTURE DATABASES OF THE NATIONAL NUCLEAR DATA CENTER.

    SciTech Connect

    PRITYCHENKO, B.; HERMAN, M.W.; MUGHABGHAB, S.F.; OBLOZINSKY, P.; SONZOGNI, A.A.

    2006-06-23

    We discuss nuclear data resources of the National Nuclear Data Center (NNDC) of relevance to nuclear astrophysics applications. These resources include databases, tools and powerful web service at www.nndc.bnl.gov. Our objective is to provide an overview of nuclear databases, related products and demonstrate nuclear astrophysics potential of the ENDF/B-VII beta2 library. A detailed discussion on the Maxwellian neutron capture cross sections obtained from the ENDF/B-VII beta2 library is presented.

  4. Accelerator Driven Nuclear Energy: The Thorium Option

    SciTech Connect

    Raja, Rajendran

    2009-03-18

    Conventional nuclear reactors use enriched Uranium as fuel and produce nuclear waste which needs to be stored away for over 10,000 years.   At the current rate of use, existing sources of Uranium will last for 50-100 years.  We describe a solution to the problem that uses particle accelerators to produce fast neutrons that can be used to burn existing nuclear waste and produce energy.  Such systems, initially proposed by Carlo Rubbia and collaborators in the 1990's, are being seriously considered by many countries as a possible solution to the green energy problem.  Accelerator driven reactors operate in a sub-critical regime and, thus, are safer and can obtain energy from plentiful elements such as Thorium-232 and Uranium-238. What is missing is the high intensity (10MW) accelerator that produces 1 GeV protons. We will describe scenarios which if implemented will make such systems a reality.  

  5. Sanitary engineering aspects of nuclear energy developments*

    PubMed Central

    Kenny, A. W.

    1962-01-01

    So many developments have taken place in the field of nuclear energy since 1956, when the author's previous paper on radioactive waste disposal was published in the Bulletin of the World Health Organization, that a fresh review of the subject is now appropriate. The present paper deals with those aspects of the problem which are of most interest to the sanitary engineer. It considers specific points in the latest recommendations of the International Commission on Radiological Protection in relation to public drinking-water supplies, and examines the problem of fall-out, with special reference to the presence and significance of strontium-90 in drinking-water. A general survey of the various uses of radioactive materials is followed by a discussion of the legislative and control measures necessary to ensure safe disposal of wastes. The methods of waste disposal adopted in a number of nuclear energy establishments are described in detail. The paper concludes with some remarks on solid waste disposal, siting of nuclear energy industries and area monitoring. PMID:14455214

  6. Accelerator Driven Nuclear Energy: The Thorium Option

    ScienceCinema

    Raja, Rajendran

    2016-07-12

    Conventional nuclear reactors use enriched Uranium as fuel and produce nuclear waste which needs to be stored away for over 10,000 years.   At the current rate of use, existing sources of Uranium will last for 50-100 years.  We describe a solution to the problem that uses particle accelerators to produce fast neutrons that can be used to burn existing nuclear waste and produce energy.  Such systems, initially proposed by Carlo Rubbia and collaborators in the 1990's, are being seriously considered by many countries as a possible solution to the green energy problem.  Accelerator driven reactors operate in a sub-critical regime and, thus, are safer and can obtain energy from plentiful elements such as Thorium-232 and Uranium-238. What is missing is the high intensity (10MW) accelerator that produces 1 GeV protons. We will describe scenarios which if implemented will make such systems a reality.  

  7. Bremsstrahlung from nuclear scattering at low energy near a resonance

    NASA Astrophysics Data System (ADS)

    Trail, C. C.; Lesser, P. M. S.; Liou, M. K.

    1984-04-01

    A program to contribute to the general understanding of nuclear reactions by determining as many of the off-shell properties of the proton-nucleus interaction as possible through the study of the proton-nucleus bremsstrahlung process is discussed. The limits of validity of a model independent analysis of these reactions in the neighborhood of a resonance or a breakup threshold are sought. The differences between this analysis and the data is utilized to elucidate those off-shell constraints which any valid proton-nucleus model interaction must satisfy. The bremsstrahlung process provides a method for determining the off-shell properties of the proton-nucleus potential, and the Brooklyn College program offers a unique opportunity to measure these crucial aspects of the low energy proton-nucleus interaction.

  8. Cutaneous reactions in nuclear, biological and chemical warfare.

    PubMed

    Arora, Sandeep

    2005-01-01

    Nuclear, biological and chemical warfare have in recent times been responsible for an increasing number of otherwise rare dermatoses. Many nations are now maintaining overt and clandestine stockpiles of such arsenal. With increasing terrorist threats, these agents of mass destruction pose a risk to the civilian population. Nuclear and chemical attacks manifest immediately while biological attacks manifest later. Chemical and biological attacks pose a significant risk to the attending medical personnel. The large scale of anticipated casualties in the event of such an occurrence would need the expertise of all physicians, including dermatologists, both military and civilian. Dermatologists are uniquely qualified in this respect. This article aims at presenting a review of the cutaneous manifestations in nuclear, chemical and biological warfare and their management.

  9. High energy electrons, positrons and photonuclear reactions in petawatt laser-solid experiments

    SciTech Connect

    Cowan, T E; Hunt, A W; Johnson, J; Perry, M D; Fountain, W; Hatchett, S; Key, M H; Kuehl, T; Parnell, T; Pennington, D M; Phillips, T W; Roth, M; Takahashi, Y; Wilks, S C

    1999-09-09

    The Petawatt laser at LLNL has opened a new regime of high-energy laser-matter interactions in which the quiver motion of plasma electrons is fully relativistic with energies extending well above the threshold for nuclear processes. We have observed that, in addition to the large flux of several MeV electrons ponderomotively expelled from the ultra-intense laser focus, there is a high energy component of electrons extending to -100 MeV, apparently from relativistic self-focusing and plasma acceleration in the underdense pre-formed plasma. The generation of hard bremsstrahlung cascade as these electrons traverse the solid target material, and the resulting photo-nuclear reactions, nuclear fission, and positron-electron pair production are described.

  10. Nuclear coherences in photosynthetic reaction centers following light excitation

    SciTech Connect

    Weber, S.; Norris, J.R.; Berthold, T.; Ohmes, E.; Kothe, G.; Thurnauer, M.C.

    1997-07-01

    Transient electron paramagnetic resonance is used to study the secondary radical pair in plant photosystem I. Nuclear coherences are observed in the transverse magnetization at lower temperatures following light excitation. Comparative studies of deuterated and deuterated {sup 15}N-substituted cyanobacteria S. lividus indicate assignment of these coherences to nitrogen nuclei in the primary donor and deuterons in the secondary acceptor. The modulation amplitude of a deuteron matrix line, as a function of the microwave power, reveals a distinct resonance behavior. The maximum amplitude is obtained when the Rabi frequency equals the nuclear Zeeman frequency.

  11. Low and medium energy deuteron-induced reactions on {sup 63,65}Cu nuclei

    SciTech Connect

    Simeckova, E.; Bem, P.; Honusek, M.; Stefanik, M.; Fischer, U.; Simakov, S. P.; Forrest, R. A.; Koning, A. J.; Sublet, J.-C.; Avrigeanu, M.; Roman, F. L.; Avrigeanu, V.

    2011-07-15

    The activation cross sections of (d,p), (d,2n), (d,3n), and (d,2p) reactions on {sup 63,65}Cu were measured in the energy range from 4 to 20 MeV using the stacked-foil technique. Then, following the available elastic-scattering data analysis that provided the optical potential for reaction cross-section calculations, an increased effort was devoted to the breakup mechanism, direct reaction stripping, and pre-equilibrium and compound-nucleus cross-section calculations, corrected for the breakup and stripping decrease of the total reaction cross section. The overall agreement between the measured and calculated deuteron activation cross sections proves the correctness of the nuclear mechanism account, next to the simultaneous analysis of the elastic-scattering and reaction data.

  12. Computed Potential Energy Surfaces for Chemical Reactions

    NASA Technical Reports Server (NTRS)

    Heinemann, K.; Walch, Stephen P.; Levin, Eugene

    1993-01-01

    A manuscript describing the calculations on the (1)CH2 + H2O, H2 + HCOH, and H2 + H2CO product channels in the CH3 + OH reaction, which were described in the last progress report, has been accepted for publication in J. Chem. Phys., and a copy of the manuscript is included in the appendix. The production of (1)CH2 in this reaction is important in hydrocarbon combustion since (1)CH2 is highly reactive and would be expected to insert into N2, possibly leading to a new source for prompt NO(x) (vide infra). During the last six months new calculations have been carried out for the NH2 + NO system, which is important in the thermal de-NO(x) process.

  13. Neutron Transfer Reactions: Surrogates for Neutron Capture for Basic and Applied Nuclear Science

    NASA Astrophysics Data System (ADS)

    Cizewski, J. A.; Jones, K. L.; Kozub, R. L.; Pain, S. D.; Peters, W. A.; Adekola, A.; Allen, J.; Bardayan, D. W.; Becker, J. A.; Blackmon, J. C.; Chae, K. Y.; Chipps, K. A.; Erikson, L.; Gaddis, A.; Harlin, C.; Hatarik, R.; Howard, J.; Jandel, M.; Johnson, M. S.; Kapler, R.; Krolas, W.; Liang, F.; Livesay, R. J.; Ma, Z.; Matei, C.; Matthews, C.; Moazen, B.; Nesaraja, C. D.; O'Malley, P.; Patterson, N.; Paulauskas, S. V.; Pelham, T.; Pittman, S. T.; Radford, D.; Rogers, J.; Schmitt, K.; Shapira, D.; Shriner, J. F.; Sissom, D. J.; Smith, M. S.; Swan, T.; Thomas, J. S.; Vieira, D. J.; Wilhelmy, J. B.; Wilson, G. L.

    2009-03-01

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on 130,132Sn, 134Te and 75As are discussed.

  14. Neutron transfer reactions: Surrogates for neutron capture for basic and applied nuclear science

    SciTech Connect

    Cizewski, J. A.; Jones, K. L.; Kozub, R. L.; Pain, Steven D; Peters, W. A.; Adekola, Aderemi S; Allen, J.; Bardayan, Daniel W; Becker, J.; Blackmon, Jeff C; Chae, K. Y.; Chipps, K.; Erikson, Luke; Gaddis, A. L.; Harlin, Christopher W; Hatarik, Robert; Howard, Joshua A; Jandel, M.; Johnson, Micah; Kapler, R.; Krolas, W.; Liang, J Felix; Livesay, Jake; Ma, Zhanwen; Matei, Catalin; Matthews, C.; Moazen, Brian; Nesaraja, Caroline D; O'Malley, Patrick; Patterson, N. P.; Paulauskas, Stanley; Pelham, T.; Pittman, S. T.; Radford, David C; Rogers, J.; Schmitt, Kyle; Shapira, Dan; ShrinerJr., J. F.; Sissom, D. J.; Smith, Michael Scott; Swan, T. P.; Thomas, J. S.; Vieira, D. J.; Wilhelmy, J. B.; Wilson, Gemma L

    2009-04-01

    Neutron capture reactions on unstable nuclei are important for both basic and applied nuclear science. A program has been developed at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory to study single-neutron transfer (d,p) reactions with rare isotope beams to provide information on neutron-induced reactions on unstable nuclei. Results from (d,p) studies on {sup 130,132}Sn, {sup 134}Te and {sup 75}As are discussed.

  15. Nuclear reactions with 11C and 14O radioactive ion beams

    SciTech Connect

    Guo, Fanqing

    2004-12-09

    Radioactive ion beams (RIBs) have been shown to be a useful tool for studying proton-rich nuclides near and beyond the proton dripline and for evaluating nuclear models. To take full advantage of RIBs, Elastic Resonance Scattering in Inverse Kinematics with Thick Targets (ERSIKTT), has proven to be a reliable experimental tool for investigations of proton unbound nuclei. Following several years of effort, Berkeley Experiments with Accelerated Radioactive Species (BEARS), a RIBs capability, has been developed at the Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. The current BEARS provides two RIBs: a 11C beam of up to 2x108 pps intensity on target and an 14O beam of up to 3x104 pps intensity. While the development of the 11C beam has been relatively easy, a number of challenges had to be overcome to obtain the 14O beam. The excellent 11C beam has been used to investigate several reactions. The first was the 197Au(11C,xn)208-xnAt reaction, which was used to measure excitation functions for the 4n to 8n exit channels. The measured cross sections were generally predicted quite well using the fusion-evaporation code HIVAP. Possible errors in the branching ratios of ?? decays from At isotopes as well as the presence of incomplete fusion reactions probably contribute to specific overpredictions. 15F has been investigated by the p(14O,p)14O reaction with the ERSIKTT technology. Several 14O+p runs have been performed. Excellent energy calibration was obtained using resonances from the p(14N,p)14N reaction in inverse kinematics, and comparing the results to those obtained earlier with normal kinematics. The differences between 14N+p and 14O+p in the stopping power function have been evaluated for better energy calibration. After careful calibration, the energy levels of 15F were fitted with an R-matrix calculation. Spins and parities were assigned to the two observed resonances. This new measurement of the 15F ground state supports the disappearance of the Z = 8

  16. Living with the nuclear threat: psychological reactions and responses

    SciTech Connect

    Hamilton, E.D.

    1986-01-01

    Thirty subjects (15 males and 15 females) at the Forestville Nursing Center, Forestville, Connecticut participated in a clinical interview that assessed attitudes towards the future in relation to the nuclear threat. Subjects did not know the topic of the research prior to the interview, but were told that it was a study about their opinions of the 1980s. The population was described with respect to demographic, socioeconomic, educational, and political variables. The main areas considered were hopefulness for their future, personal action in response to the nuclear threat, and beliefs concerning the effectiveness of that action. Results supported and enlarged upon literature theories concerning peoples' beliefs about the future. Only 23.3% of the subjects made hopeful predictions for the future of the world and 50% made hopeful predictions for North America. Where subjects' personnel future was concerned 80% felt hopeful. Other literature claims concerning powerlessness and beliefs concerning the effect of action were also supported. Ninety-three per cent of the subjects were inactive and 83.3% believed actions they might take would be ineffective. Additional findings showed that over 50% of the subjects believed living with the nuclear threat had an effect on them personally, 50% saw an effect on their families, 40% an effect on friends, and 96.7% an effect on society. Without prior cueing, 66.7% brought up nuclear concerns before the topic was introduced by the interviewer, indicating that in this sample there was a fairly high level of awareness about the issue.

  17. LDRD Final Report: Surrogate Nuclear Reactions and the Origin of the Heavy Elements (04-ERD-057)

    SciTech Connect

    Escher, J E; Bernstein, L A; Bleuel, D; Burke, J; Church, J A; Dietrich, F S; Forssen, C; Gueorguiev, V; Hoffman, R D

    2007-02-23

    Research carried out in the framework of the LDRD project ''Surrogate Nuclear Reactions and the Origin of the Heavy Elements'' (04-ERD-057) is summarized. The project was designed to address the challenge of determining cross sections for nuclear reactions involving unstable targets, with a particular emphasis on reactions that play a key role in the production of the elements between Iron and Uranium. This report reviews the motivation for the research, introduces the approach employed to address the problem, and summarizes the resulting scientific insights, technical findings, and related accomplishments.

  18. Emerging nuclear energy systems: Economic challenge: Revision 1

    SciTech Connect

    Nuckolls, J.H.

    1986-01-01

    Future nuclear energy systems may achieve substantially lower energy costs than those of existing fossil energy systems and comparable capital costs. Such low cost nuclear energy would provide a strong economic incentive to minimize the use of fossil fuels. If these low cost nuclear energy systems emerge in the next few decades, 21st century civilization may be able to avert potentially disastrous CO/sub 2/ induced global climate changes. 12 refs., 1 fig.

  19. Ultraperipheral Pb+Pb reactions at LHC energies

    NASA Astrophysics Data System (ADS)

    Norbeck, Edwin; Onel, Yasar

    2011-10-01

    The magnetic field midway between two Pb nuclei passing at 20 fm is 2 × 1020 gauss at LHC energies (1144 TeV in PbPb center of mass). At these energies the Coulomb field of a passing Pb nucleus can be regarded as a cloud of real photons. The cross sections for γγ and γA reactions are huge compared to 7 b for two Pb nuclei actually colliding. The reaction rate is limited by the 323 b cross section for breaking up the Pb nucleus or for the capture by a Pb ion of an e- from the many e+ e- pairs that are formed. These products go down the beam pipe and eventually hit superconducting magnets. The γγ reactions can produce particles with mc2 up to 100 GeV. The γA reactions can produce particles with mc2 more than 900 GeV. These ultraperipheral reactions are particularly clean. In proton-proton reactions, the reaction between two partons to produce something of interest is accompanied by a large background caused by many other parton-parton reactions. When γA breaks up a Pb nucleus, the transverse energy is small so that the fragments continue in the original beam direction. A single neutron in the original beam direction provides a useful flag that shows that an ultraperipheral reaction has occurred.

  20. Proposal for a High Energy Nuclear Database

    SciTech Connect

    Brown, David A.; Vogt, Ramona

    2005-03-31

    We propose to develop a high-energy heavy-ion experimental database and make it accessible to the scientific community through an on-line interface. This database will be searchable and cross-indexed with relevant publications, including published detector descriptions. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support. This database should eventually contain all published data from Bevalac and AGS to RHIC to CERN-LHC energies, proton-proton to nucleus-nucleus collisions as well as other relevant systems, and all measured observables. Such a database would have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models to a broad range of old and new experiments. Furthermore, there is a growing need for compilations of high-energy nuclear data for applications including stockpile stewardship, technology development for inertial confinement fusion and target and source development for upcoming facilities such as the Next Linear Collider. To enhance the utility of this database, we propose periodically performing evaluations of the data and summarizing the results in topical reviews.

  1. Proposal for a High Energy Nuclear Database

    SciTech Connect

    Brown, D A; Vogt, R

    2005-03-31

    The authors propose to develop a high-energy heavy-ion experimental database and make it accessible to the scientific community through an on-line interface. This database will be searchable and cross-indexed with relevant publications, including published detector descriptions. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support. This database should eventually contain all published data from Bevalac, AGS and SPS to RHIC and CERN-LHC energies, proton-proton to nucleus-nucleus collisions as well as other relevant systems, and all measured observables. Such a database would have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models to a broad range of old and new experiments. Furthermore, there is a growing need for compilations of high-energy nuclear data for applications including stockpile stewardship, technology development for inertial confinement fusion and target and source development for upcoming facilities such as the Next Linear Collider. To enhance the utility of this database, they propose periodically performing evaluations of the data and summarizing the results in topical reviews.

  2. Perspectives of Nuclear Energy for Human Development

    SciTech Connect

    Rouyer, Jean-Loup

    2002-07-01

    In this period of expectation and short term viewing, everyone has difficulties to draw long term perspectives. A positive global world vision of sustainable development gives confidence in the preparation of energy future in a moving international context. This presentation proposes to share such a long term vision inside which energy scenarios for nuclear development take their right place. It is founded on a specific analysis of an index of countries global development which is representative of a country efficiency. Human Development Index (HDI) is a composite international index recommended and calculated every year since 1990 by the United Nations Development Program (UNDP). This index is still very dependent of GNP, which ignores the disparities of revenues inside the country. That is why a Country Efficiency Index (CEI) has been defined to better represent the capacity of a country to utilize its resources for welfare of its inhabitants. CEI is a ratio of health and education levels to the capacity of the country to satisfy this welfare. CEI has been calculated for the 70 more populated countries of the world for the year 1997. CEI calculation has been also performed for European Countries, the United States, China and India on the period from 1965 to 1997. It is observed a growth of CEI. for France from 0.6 to 0.78, and from 0.7 to 0.85 for USA. In 1997, CEI of China was 0.46, and 0.38 for India. This index is a good tool to measure the progression of development of the countries and the related energy needs. Comparison of the evolutions of CEI of these different countries shows a similar positive trend with some delay between OECD countries and China or India. A positive scenario for the future is based on a similar curve for these developing countries with learning effect which produces development with less energy consumption. This simulation results however in energy needs that exceed fossil fuel today available resources in 2070. Ultimate fossil

  3. Probing the nuclear structure with heavy-ion reactions

    SciTech Connect

    Broglia, R.A.

    1982-01-01

    Nuclei display distortions in both ordinary space and in gauge space. It is suggested that it is possible to learn about the spatial distribution of the Nilsson orbitals and about the change of the pairing gap with the rotational frequency through the analysis of one- and two-nucleon transfer reactions induced in heavy-ion collisions.

  4. SURFACE SYMMETRY ENERGY OF NUCLEAR ENERGY DENSITY FUNCTIONALS

    SciTech Connect

    Nikolov, N; Schunck, N; Nazarewicz, W; Bender, M; Pei, J

    2010-12-20

    We study the bulk deformation properties of the Skyrme nuclear energy density functionals. Following simple arguments based on the leptodermous expansion and liquid drop model, we apply the nuclear density functional theory to assess the role of the surface symmetry energy in nuclei. To this end, we validate the commonly used functional parametrizations against the data on excitation energies of superdeformed band-heads in Hg and Pb isotopes, and fission isomers in actinide nuclei. After subtracting shell effects, the results of our self-consistent calculations are consistent with macroscopic arguments and indicate that experimental data on strongly deformed configurations in neutron-rich nuclei are essential for optimizing future nuclear energy density functionals. The resulting survey provides a useful benchmark for further theoretical improvements. Unlike in nuclei close to the stability valley, whose macroscopic deformability hangs on the balance of surface and Coulomb terms, the deformability of neutron-rich nuclei strongly depends on the surface-symmetry energy; hence, its proper determination is crucial for the stability of deformed phases of the neutron-rich matter and description of fission rates for r-process nucleosynthesis.

  5. Calculating Ring Pucker Free Energy Surfaces From Reaction Coordinate Forces

    SciTech Connect

    Barnett, Christopher B.; Naidoo, Kevin J.

    2009-03-09

    We implemented the free energy from adaptive reaction coordinate forces (FEARCF) method and applied it to the conformational investigation of carbohydrate ring puckering. The method allows for significantly enhanced sampling of reaction coordinate space. The free energies associated with the ring pucker motion of {beta}-D-ribose (a furanose) and {beta}-D-glucose (a pyranose) were calculated. These can be used to interpret catalytic mechanisms of glycosylases.

  6. Global Nuclear Energy Partnership Waste Treatment Baseline

    SciTech Connect

    Dirk Gombert; William Ebert; James Marra; Robert Jubin; John Vienna

    2008-05-01

    The Global Nuclear Energy Partnership program (GNEP) is designed to demonstrate a proliferation-resistant and sustainable integrated nuclear fuel cycle that can be commercialized and used internationally. Alternative stabilization concepts for byproducts and waste streams generated by fuel recycling processes were evaluated and a baseline of waste forms was recommended for the safe disposition of waste streams. Waste forms are recommended based on the demonstrated or expected commercial practicability and technical maturity of the processes needed to make the waste forms, and performance of the waste form materials when disposed. Significant issues remain in developing technologies to process some of the wastes into the recommended waste forms, and a detailed analysis of technology readiness and availability may lead to the choice of a different waste form than what is recommended herein. Evolving regulations could also affect the selection of waste forms.

  7. MCNPX simulations of the silicon carbide semiconductor detector response to fast neutrons from D-T nuclear reaction

    NASA Astrophysics Data System (ADS)

    Sedlačková, Katarína; Šagátová, Andrea; Zat'ko, Bohumír; Nečas, Vladimír; Solar, Michael; Granja, Carlos

    2016-09-01

    Silicon Carbide (SiC) has been long recognized as a suitable semiconductor material for use in nuclear radiation detectors of high-energy charged particles, gamma rays, X-rays and neutrons. The nuclear interactions occurring in the semiconductor are complex and can be quantified using a Monte Carlo-based computer code. In this work, the MCNPX (Monte Carlo N-Particle eXtended) code was employed to support detector design and analysis. MCNPX is widely used to simulate interaction of radiation with matter and supports the transport of 34 particle types including heavy ions in broad energy ranges. The code also supports complex 3D geometries and both nuclear data tables and physics models. In our model, monoenergetic neutrons from D-T nuclear reaction were assumed as a source of fast neutrons. Their energy varied between 16 and 18.2 MeV, according to the accelerating voltage of the deuterons participating in D-T reaction. First, the simulations were used to calculate the optimum thickness of the reactive film composed of High Density PolyEthylene (HDPE), which converts neutral particles to charged particles and thusly enhancing detection efficiency. The dependency of the optimal thickness of the HDPE layer on the energy of the incident neutrons has been shown for the inspected energy range. Further, from the energy deposited by secondary charged particles and recoiled ions, the detector response was modeled and the effect of the conversion layer on detector response was demonstrated. The results from the simulations were compared with experimental data obtained for a detector covered by a 600 and 1300 μm thick conversion layer. Some limitations of the simulations using MCNPX code are also discussed.

  8. Nuclear binding energy and symmetry energy of nuclear matter with modern nucleon-nucleon potentials

    SciTech Connect

    Hassaneen, Kh.S.A.; Abo-Elsebaa, H.M.; Sultan, E.A.; Mansour, H.M.M.

    2011-03-15

    Research Highlights: > The nuclear matter is studied within the Brueckner-Hartree-Fock (BHF) approach employing the most recent accurate nucleon-nucleon potentials. > The results come out by approximating the single particle self-consistent potential with a parabolic form. > We discuss the current status of the Coester line, i.e., density and energy of the various saturation points being strongly linearly correlated. > The nuclear symmetry energy is calculated as the difference between the binding energy of pure neutron matter and that of symmetric nuclear matter. - Abstract: The binding energy of nuclear matter at zero temperature in the Brueckner-Hartree-Fock approximation with modern nucleon-nucleon potentials is studied. Both the standard and continuous choices of single particle energies are used. These modern nucleon-nucleon potentials fit the deuteron properties and are phase shifts equivalent. Comparison with other calculations is made. In addition we present results for the symmetry energy obtained with different potentials, which is of great importance in astrophysical calculation.

  9. Neutrino-induced reactions and neutrino scattering with nuclei in low and high neutrino energy

    NASA Astrophysics Data System (ADS)

    Cheoun, Myung-Ki; Ha, Eunja; Yang, Ghil-Seok; Kim, K. S.; Kajino, T.

    2016-06-01

    We reviewed present status regarding theoretical approaches for neutrino-induced reactions and neutrino scattering. With a short introduction of relevant data, our recent calculations by distorted-wave Born approximation (DWBA) for quasielastic region are presented for MiniBooNE data. We also discussed that one step-process estimated by the DWBA is comparable to the two-step process, which has been usually used in the neutrino-nucleosynthesis. For much higher energy neutrino data, such as NOMAD data, elementary process approach was shown to be useful instead of using complicated nuclear models. But, in the low energy region, detailed nuclear structure model, such as QRPA and shell model, turn out to be inescapable to explain the reaction data.

  10. Deuteron Induced ( d,p) and ( d,2p) Nuclear Reactions up to 50 MeV

    NASA Astrophysics Data System (ADS)

    Yiğit, M.; Tel, E.; Kara, A.

    2013-06-01

    Many studies have shown that the nuclear reactions of charged particles with nuclei are very important in many fields of nuclear physics. The interactions of deuterons with nuclei have been especially the subject of common research in the history of nuclear physics. Moreover, the knowledge of cross section for deuteron-nucleus interactions are required for various application such as space applications, accelerator driven sub-critical systems, nuclear medicine, nuclear fission reactors and controlled thermonuclear fusion reactors. Particularly, the future of controlled thermonuclear fusion reactors is largely dependent on the nuclear reaction cross section data and the selection of structural fusion materials. Finally, the reaction cross section data of deuteron induced reactions on fusion structural materials are of great importance for development and design of both experimental and commercial fusion devices. In this work, reaction model calculations of the cross sections of deuteron induced reactions on structural fusion materials such as Al ( Aluminium), Ti ( Titanium), Cu ( Copper), Ni ( Nickel), Co ( Cobalt), Fe ( Iron), Zr ( Zirconium), Hf ( Hafnium) and Ta ( Tantalum) have been investigated. The new calculations on the excitation functions of 27 Al( d,2p) 27 Mg, 47 Ti( d,2p) 47 Sc, 65 Cu( d,2p) 65 Ni, 58 Ni( d,2p) 58 Co, 59 Co( d,2p) 59 Fe, 58 Fe( d,p) 59 Fe, 96 Zr( d,p) 97 Zr, 180 Hf ( d,p) 181 Hf and 181 Ta( d,p) 182 Ta have been carried out for incident deuteron energies up to 50 MeV. In these calculations, the equilibrium and pre-equilibrium effects for ( d,p) and ( d,2p) reactions have been investigated. The equilibrium effects are calculated according to the Weisskopf-Ewing ( WE) Model. The pre-equilibrium calculations involve the new evaluated the Geometry Dependent Hybrid Model ( GDH) and Hybrid Model. In the calculations the program code ALICE/ASH was used. The calculated results are discussed and compared with the experimental data taken from the

  11. Ligand reorganization and activation energies in nonadiabatic electron transfer reactions

    NASA Astrophysics Data System (ADS)

    Zhu, Jianjun; Wang, Jianji; Stell, George

    2006-10-01

    The activation energy and ligand reorganization energy for nonadiabatic electron transfer reactions in chemical and biological systems are investigated in this paper. The free energy surfaces and the activation energy are derived exactly in the general case in which the ligand vibration frequencies are not equal. The activation energy is derived by free energy minimization at the transition state. Our formulation leads to the Marcus-Hush [J. Chem. Phys. 24, 979 (1956); 98, 7170 (1994); 28, 962 (1958)] results in the equal-frequency limit and also generalizes the Marcus-Sumi [J. Chem. Phys. 84, 4894 (1986)] model in the context of studying the solvent dynamic effect on electron transfer reactions. It is found that when the ligand vibration frequencies are different, the activation energy derived from the Marcus-Hush formula deviates by 5%-10% from the exact value. If the reduced reorganization energy approximation is introduced in the Marcus-Hush formula, the result is almost exact.

  12. Calculation of reaction energies and adiabatic temperatures for waste tank reactions

    SciTech Connect

    Burger, L.L.

    1995-10-01

    Continual concern has been expressed over potentially hazardous exothermic reactions that might occur in Hanford Site underground waste storage tanks. These tanks contain many different oxidizable compounds covering a wide range of concentrations. The chemical hazards are a function of several interrelated factors, including the amount of energy (heat) produced, how fast it is produced, and the thermal absorption and heat transfer properties of the system. The reaction path(s) will determine the amount of energy produced and kinetics will determine the rate that it is produced. The tanks also contain many inorganic compounds inert to oxidation. These compounds act as diluents and can inhibit exothermic reactions because of their heat capacity and thus, in contrast to the oxidizable compounds, provide mitigation of hazardous reactions. In this report the energy that may be released when various organic and inorganic compounds react is computed as a function of the reaction-mix composition and the temperature. The enthalpy, or integrated heat capacity, of these compounds and various reaction products is presented as a function of temperature; the enthalpy of a given mixture can then be equated to the energy release from various reactions to predict the maximum temperature which may be reached. This is estimated for several different compositions. Alternatively, the amounts of various diluents required to prevent the temperature from reaching a critical value can be estimated. Reactions taking different paths, forming different products such as N{sub 2}O in place of N{sub 2} are also considered, as are reactions where an excess of caustic is present. Oxidants other than nitrate and nitrite are considered briefly.

  13. Experiments on screening effect in deuteron fusion reactions at extremely low energies

    NASA Astrophysics Data System (ADS)

    Targosz-Ślȩczka, N.; Czerski, K.; Huke, A.; Ruprecht, G.; Weissbach, D.; Martin, L.; Kiliç, A. i.; Kaczmarski, M.; Winter, H.

    2013-10-01

    The enhanced electron screening effect in nuclear reactions taking place in dense astrophysical plasmas is extremely important for determination of stellar reaction rates in terrestrial laboratories as well as in prediction of cross sections enhancement in interiors of stars such as White and Brown Dwarfs or Giant Planets. This effect resulting in reduction of the nuclear Coulomb potential by the atomic electrons has been confirmed in many laboratory experiments. Unfortunately, experimental screening energies are much higher than the theoretical predictions and the reason for that remains unknown. Here, we present absorbing results of the experiment studying d + d nuclear reactions in different deuterized metallic targets under ultra high vacuum conditions. The total cross sections and angular distributions of the 2H( d, p)3H and 2H( d, n)3He reactions have been measured using a deuteron beam of energies between 8 and 30 keV provided by the electron cyclotron ion source. The atomic cleanness of the target surface has been secured by combining Ar sputtering of the target and Auger electrons spectroscopy. Due to application of an on-line analysis method, the homogeneity of the implanted deuteron densities could be continuously monitored. We will discuss probable causes of the large discrepancy between theoretical and experimental data.

  14. Bifurcations on Potential Energy Surfaces of Organic Reactions

    PubMed Central

    Ess, Daniel H.; Wheeler, Steven E.; Iafe, Robert G.; Xu, Lai; Çelebi-Ölçüm, Nihan; Houk, K. N.

    2009-01-01

    A single transition state may lead to multiple intermediates or products if there is a post-transition state reaction path bifurcation. These bifurcations arise when there are sequential transition states with no intervening energy minimum. For such systems, the shape of the potential energy surface and dynamic effects control selectivity rather than transition state energetics. This minireview covers recent investigations of organic reactions exhibiting reaction pathway bifurcations. Such phenomena are surprisingly general and affect experimental observables such as kinetic isotope effects and product distributions. PMID:18767086

  15. Reaction mechanism and reaction coordinates from the viewpoint of energy flow.

    PubMed

    Li, Wenjin; Ma, Ao

    2016-03-21

    Reaction coordinates are of central importance for correct understanding of reaction dynamics in complex systems, but their counter-intuitive nature made it a daunting challenge to identify them. Starting from an energetic view of a reaction process as stochastic energy flows biased towards preferred channels, which we deemed the reaction coordinates, we developed a rigorous scheme for decomposing energy changes of a system, both potential and kinetic, into pairwise components. The pairwise energy flows between different coordinates provide a concrete statistical mechanical language for depicting reaction mechanisms. Application of this scheme to the C7eq → C7ax transition of the alanine dipeptide in vacuum revealed novel and intriguing mechanisms that eluded previous investigations of this well studied prototype system for biomolecular conformational dynamics. Using a cost function developed from the energy decomposition components by proper averaging over the transition path ensemble, we were able to identify signatures of the reaction coordinates of this system without requiring any input from human intuition.

  16. Reaction mechanism and reaction coordinates from the viewpoint of energy flow

    NASA Astrophysics Data System (ADS)

    Li, Wenjin; Ma, Ao

    2016-03-01

    Reaction coordinates are of central importance for correct understanding of reaction dynamics in complex systems, but their counter-intuitive nature made it a daunting challenge to identify them. Starting from an energetic view of a reaction process as stochastic energy flows biased towards preferred channels, which we deemed the reaction coordinates, we developed a rigorous scheme for decomposing energy changes of a system, both potential and kinetic, into pairwise components. The pairwise energy flows between different coordinates provide a concrete statistical mechanical language for depicting reaction mechanisms. Application of this scheme to the C7eq → C7ax transition of the alanine dipeptide in vacuum revealed novel and intriguing mechanisms that eluded previous investigations of this well studied prototype system for biomolecular conformational dynamics. Using a cost function developed from the energy decomposition components by proper averaging over the transition path ensemble, we were able to identify signatures of the reaction coordinates of this system without requiring any input from human intuition.

  17. 10 CFR 70.11 - Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory Commission contracts. 70.11 Section 70.11 Energy NUCLEAR... using special nuclear material under certain Department of Energy and Nuclear Regulatory...

  18. 10 CFR 70.11 - Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory Commission contracts. 70.11 Section 70.11 Energy NUCLEAR... using special nuclear material under certain Department of Energy and Nuclear Regulatory...

  19. 10 CFR 70.11 - Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory Commission contracts. 70.11 Section 70.11 Energy NUCLEAR... using special nuclear material under certain Department of Energy and Nuclear Regulatory...

  20. 10 CFR 70.11 - Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory Commission contracts. 70.11 Section 70.11 Energy NUCLEAR... using special nuclear material under certain Department of Energy and Nuclear Regulatory...

  1. 10 CFR 70.11 - Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Persons using special nuclear material under certain Department of Energy and Nuclear Regulatory Commission contracts. 70.11 Section 70.11 Energy NUCLEAR... using special nuclear material under certain Department of Energy and Nuclear Regulatory...

  2. Detailed Reaction Kinetics for CFD Modeling of Nuclear Fuel Pellet Coating for High Temperature Gas-Cooled Reactors

    SciTech Connect

    Battaglia, Francine

    2008-11-29

    The research project was related to the Advanced Fuel Cycle Initiative and was in direct alignment with advancing knowledge in the area of Nuclear Fuel Development related to the use of TRISO fuels for high-temperature reactors. The importance of properly coating nuclear fuel pellets received a renewed interest for the safe production of nuclear power to help meet the energy requirements of the United States. High-temperature gas-cooled nuclear reactors use fuel in the form of coated uranium particles, and it is the coating process that was of importance to this project. The coating process requires four coating layers to retain radioactive fission products from escaping into the environment. The first layer consists of porous carbon and serves as a buffer layer to attenuate the fission and accommodate the fuel kernel swelling. The second (inner) layer is of pyrocarbon and provides protection from fission products and supports the third layer, which is silicon carbide. The final (outer) layer is also pyrocarbon and provides a bonding surface and protective barrier for the entire pellet. The coating procedures for the silicon carbide and the outer pyrocarbon layers require knowledge of the detailed kinetics of the reaction processes in the gas phase and at the surfaces where the particles interact with the reactor walls. The intent of this project was to acquire detailed information on the reaction kinetics for the chemical vapor deposition (CVD) of carbon and silicon carbine on uranium fuel pellets, including the location of transition state structures, evaluation of the associated activation energies, and the use of these activation energies in the prediction of reaction rate constants. After the detailed reaction kinetics were determined, the reactions were implemented and tested in a computational fluid dynamics model, MFIX. The intention was to find a reduced mechanism set to reduce the computational time for a simulation, while still providing accurate results

  3. Update on DOE's Nuclear Energy University Program

    NASA Astrophysics Data System (ADS)

    Lambregts, Marsha J.

    2009-08-01

    The Nuclear Energy University Program (NEUP) Office assists the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) by administering its University Program. To promote accountable relationships between universities and the Technical Integration Offices (TIOs)/Technology Development Offices (TDOs), a process was designed and administered which includes two competitive Requests for Proposals (RFPs) and two Funding Opportunity Announcements (FOAs) in the following areas: (1) Research and Development (R&D) Grants, (2) Infrastructure improvement, and (3) Scholarships and Fellowships. NEUP will also host periodic reviews of university mission-specific R&D that document progress, reinforce accountability, and assess return on investment; sponsor workshops that inform universities of the Department's research needs to facilitate continued alignment of university R&D with NE missions; and conduct communications activities that foster stakeholder trust, serve as a catalyst for accomplishing NEUP objectives, and provide national visibility of NEUP activities and accomplishments. Year to date efforts to achieve these goals will be discussed.

  4. Update on DOE's Nuclear Energy University Program

    SciTech Connect

    Lambregts, Marsha J.

    2009-08-19

    The Nuclear Energy University Program (NEUP) Office assists the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) by administering its University Program. To promote accountable relationships between universities and the Technical Integration Offices (TIOs)/Technology Development Offices (TDOs), a process was designed and administered which includes two competitive Requests for Proposals (RFPs) and two Funding Opportunity Announcements (FOAs) in the following areas: (1) Research and Development (R and D) Grants, (2) Infrastructure improvement, and (3) Scholarships and Fellowships. NEUP will also host periodic reviews of university mission-specific R and D that document progress, reinforce accountability, and assess return on investment; sponsor workshops that inform universities of the Department's research needs to facilitate continued alignment of university R and D with NE missions; and conduct communications activities that foster stakeholder trust, serve as a catalyst for accomplishing NEUP objectives, and provide national visibility of NEUP activities and accomplishments. Year to date efforts to achieve these goals will be discussed.

  5. Overview of Nuclear Energy: Present and Projected Use

    SciTech Connect

    Alexander Stanculescu

    2011-09-01

    Several factors will influence the contribution of nuclear energy to the future energy mix. Among them, the most important are the degree of global commitment to greenhouse gas reduction, continued vigilance in safety and safeguards, technological advances, economic competitiveness and innovative financing arrangements for new nuclear power plant constructions, the implementation of nuclear waste disposal, and, last but not least, public perception, information and education. The paper presents an overview of the current nuclear energy situation, possible development scenarios, of reactor technology, and of non-electric applications of nuclear energy.

  6. Overview of nuclear energy: Present and projected use

    SciTech Connect

    Stanculescu, Alexander

    2012-06-19

    Several factors will influence the contribution of nuclear energy to the future energy mix. Among them, the most important are the degree of global commitment to greenhouse gas reduction, continued vigilance in safety and safeguards, technological advances, economic competitiveness and innovative financing arrangements for new nuclear power plant constructions, the implementation of nuclear waste disposal, and, last but not least, public perception, information and education. The paper presents an overview of the current nuclear energy situation, possible development scenarios, of reactor technology, and of non-electric applications of nuclear energy.

  7. Overview of nuclear energy: Present and projected use

    NASA Astrophysics Data System (ADS)

    Stanculescu, Alexander

    2012-06-01

    Several factors will influence the contribution of nuclear energy to the future energy mix. Among them, the most important are the degree of global commitment to greenhouse gas reduction, continued vigilance in safety and safeguards, technological advances, economic competitiveness and innovative financing arrangements for new nuclear power plant constructions, the implementation of nuclear waste disposal, and, last but not least, public perception, information and education. The paper presents an overview of the current nuclear energy situation, possible development scenarios, of reactor technology, and of non-electric applications of nuclear energy.

  8. Nuclear's role in 21. century Pacific rim energy use

    SciTech Connect

    Singer, Clifford; Taylor, J'Tia

    2007-07-01

    Extrapolations contrast the future of nuclear energy use in Japan and the Republic of Korea (ROK) to that of the Association of Southeast Asian Nations (ASEAN). Japan can expect a gradual rise in the nuclear fraction of a nearly constant total energy use rate as the use of fossil fuels declines. ROK nuclear energy rises gradually with total energy use. ASEAN's total nuclear energy use rate can rapidly approach that of the ROK if Indonesia and Vietnam make their current nuclear energy targets by 2020, but experience elsewhere suggests that nuclear energy growth may be slower than planned. Extrapolations are based on econometric calibration to a utility optimization model of the impact of growth of population, gross domestic product, total energy use, and cumulative fossil carbon use. Fractions of total energy use from fluid fossil fuels, coal, water-driven electrical power production, nuclear energy, and wind and solar electric energy sources are fit to market fractions data. Where historical data is insufficient for extrapolation, plans for non-fossil energy are used as a guide. Extrapolations suggest much more U.S. nuclear energy and spent nuclear fuel generation than for the ROK and ASEAN until beyond the first half of the twenty-first century. (authors)

  9. Energy Fuels Nuclear, Inc. Arizona Strip Operations

    SciTech Connect

    Pool, T.C.

    1993-05-01

    Founded in 1975 by uranium pioneer, Robert W. Adams, Energy Fuels Nuclear, Inc. (EFNI) emerged as the largest US uranium mining company by the mid-1980s. Confronting the challenges of declining uranium market prices and the development of high-grade ore bodies in Australia and Canada, EFNI aggressively pursued exploration and development of breccia-pipe ore bodies in Northwestern Arizona. As a result, EFNI's production for the Arizona Strip of 18.9 million pounds U[sub 3]O[sub 8] over the period 1980 through 1991, maintained the company's status as a leading US uranium producer.

  10. Nuclear stopping in oxygen-induced reactions at 200 A GeV

    SciTech Connect

    Obenshain, F.E.; Albrecht, R.; Awes, T.C.; Baktash, C.; Beckmann, P.; Berger, F.; Bock, R.; Claesson, G.; Dragon, L.; Ferguson, R.L.

    1988-01-01

    Measurements of transverse energy and energy at zero degrees are compared with the results of a Glauber-type multiple collision model calculations. The best fit to the data shows that the degree of nuclear stopping is large. This theoretical model also predicts energy densities and shows how the energy density changes as the projectile and target masses change. 10 refs., 5 figs.

  11. Nuclear Energy Response in the EMF27 Study

    SciTech Connect

    Kim, Son H.; Wada, Kenichi; Kurosawa, Atsushi; Roberts, Matthew

    2014-03-25

    The nuclear energy response for mitigating global climate change across eighteen participating models of the EMF27 study is investigated. Diverse perspectives on the future role of nuclear power in the global energy system are evident in the broad range of nuclear power contributions from participating models of the study. In the Baseline scenario without climate policy, nuclear electricity generation and shares span 0 – 66 EJ/ year and 0 - 25% in 2100 for all models, with a median nuclear electricity generation of 39 EJ/year (1,389 GWe at 90% capacity factor) and median share of 9%. The role of nuclear energy increased under the climate policy scenarios. The median of nuclear energy use across all models doubled in the 450 ppm CO2e scenario with a nuclear electricity generation of 67 EJ/year (2,352 GWe at 90% capacity factor) and share of 17% in 2100. The broad range of nuclear electricity generation (11 – 214 EJ/year) and shares (2 - 38%) in 2100 of the 450 ppm CO2e scenario reflect differences in the technology choice behavior, technology assumptions and competitiveness of low carbon technologies. Greater clarification of nuclear fuel cycle issues and risk factors associated with nuclear energy use are necessary for understanding the nuclear deployment constraints imposed in models and for improving the assessment of the nuclear energy potential in addressing climate change.

  12. A new study of 10B(p,α)7Be reaction at low energies

    NASA Astrophysics Data System (ADS)

    Caciolli, A.; Depalo, R.; Broggini, C.; La Cognata, M.; Lamia, L.; Menegazzo, R.; Mou, L.; Puglia, S. M. R.; Rigato, V.; Romano, S.; Rossi Alvarez, C.; Sergi, M. L.; Spitaleri, C.; Tumino, A.

    2016-05-01

    The 10B(p,α)7Be reaction is of great interest since it has many applications in different fields of research such as nuclear astrophysics, nuclear physics, and models of new reactors for clean energy generation. This reaction has been studied at the AN2000 accelerator of the INFN National Laboratories of Legnaro (LNL). The total cross section has been measured in a wide energy range (250-1182 keV) by using the activation method. The decays of the 7Be nuclei produced by the reaction were measured at the low counting facility of LNL by using two fully shielded high-purity germanium detectors. The present dataset shows a large discrepancy with respect to one of the previous data at the same energies and reduces the total uncertainty to the level of 6%. An R-matrix calculation has been performed on the present data using the parameters from previous Trojan Horse measurements for the 10 and 500keV resonances. The present data do not lay on the R-matrix fit in one point suggesting the existence of a 11C level not observed yet. Further nuclear investigations are needed to confirm this hypothesis.

  13. Production of new heavy isotopes in low-energy multinucleon transfer reactions.

    PubMed

    Zagrebaev, Valery; Greiner, Walter

    2008-09-19

    It is shown that the multinucleon transfer reactions in low-energy collisions of heavy ions may be used for production of new neutron-rich nuclei at the "northeast" part of the nuclear map along the neutron closed shell N=126 which plays an important role in the r process of nucleosynthesis. More than 50 unknown nuclei might be produced in such reactions (in particular, in collision of 136Xe with 208Pb) with cross sections of not less than 1 microb. PMID:18851367

  14. [Reaction mechanism studies of heavy ion induced nuclear reactions]. [Dept. of Chemistry and Biochemistry, Univ. of Maryland, College Park, Maryland

    SciTech Connect

    Mignerey, A.C.

    1993-02-01

    Completed work is summarized on the topics of excitation energy division in deep-inelastic reactions and the onset of multifragmentation in La-induced reactions at E/A = 45 MeV. Magnetic fields are being calculated for the PHOBOS detector system, a two-arm multiparticle spectrometer for studying low-transverse-momentum particles produced at the Relativistic Heavy Ion Collider. The Maryland Forward Array is being developed for detection of the reaction products from very peripheral collisions; it consists of two individual units of detectors: the annular silicon detector in front and the plastic phoswich detector at back.

  15. Nuclear Energy and Synthetic Liquid Transportation Fuels

    NASA Astrophysics Data System (ADS)

    McDonald, Richard

    2012-10-01

    This talk will propose a plan to combine nuclear reactors with the Fischer-Tropsch (F-T) process to produce synthetic carbon-neutral liquid transportation fuels from sea water. These fuels can be formed from the hydrogen and carbon dioxide in sea water and will burn to water and carbon dioxide in a cycle powered by nuclear reactors. The F-T process was developed nearly 100 years ago as a method of synthesizing liquid fuels from coal. This process presently provides commercial liquid fuels in South Africa, Malaysia, and Qatar, mainly using natural gas as a feedstock. Nuclear energy can be used to separate water into hydrogen and oxygen as well as to extract carbon dioxide from sea water using ion exchange technology. The carbon dioxide and hydrogen react to form synthesis gas, the mixture needed at the beginning of the F-T process. Following further refining, the products, typically diesel and Jet-A, can use existing infrastructure and can power conventional engines with little or no modification. We can then use these carbon-neutral liquid fuels conveniently long into the future with few adverse environmental impacts.

  16. Identification of colloids in nuclear waste glass reactions

    SciTech Connect

    Cunnane, J.C.; Bates, J.K.

    1991-01-01

    Characterization data for particulates formed under a variety of laboratory leaching conditions that simulate glass reaction in a repository environment are presented. Data on the particle size distributions and filterable fractions for neptunium, plutonium, americium, and curium were obtained by filtrations through a series of filters with pore sizes ranging from 1 {mu}m to 3.8 nm. The neptunium was found to be largely nonfilterable. Americium and plutonium were associated with filterable particles. The particles with which the americium, plutonium, and curium were associated were characterized using transmission electron microscopy (TEM) examination techniques. 8 refs., 1 fig., 2 tabs.

  17. Results on the neutron energy distribution measurements at the RECH-1 Chilean nuclear reactor

    NASA Astrophysics Data System (ADS)

    Aguilera, P.; Molina, F.; Romero-Barrientos, J.

    2016-07-01

    Neutron activations experiments has been perform at the RECH-1 Chilean Nuclear Reactor to measure its neutron flux energy distribution. Samples of pure elements was activated to obtain the saturation activities for each reaction. Using - ray spectroscopy we identify and measure the activity of the reaction product nuclei, obtaining the saturation activities of 20 reactions. GEANT4 and MCNP was used to compute the self shielding factor to correct the cross section for each element. With the Expectation-Maximization algorithm (EM) we were able to unfold the neutron flux energy distribution at dry tube position, near the RECH-1 core. In this work, we present the unfolding results using the EM algorithm.

  18. A Study of the Nuclear Structure at High Energy and Low Spin

    NASA Astrophysics Data System (ADS)

    Rekstad, J.; Henriquez, A.; Ingebretsen, F.; Midttun, G.; Skaali, B.; Øyan, R.; Wikne, J.; Engeland, T.; Thorsteinsen, T. F.; Hammaren, E.; Liukkonen, E.

    1983-01-01

    A novel method to study nuclear structure at low spin as a function of temperature is developed and used on 146,148Sm, 154,156Gd and 160,162Dy, by means of the (3He, α) reaction. The nuclear level density for a wide energy range is also studied. The γ-multiplicities and the first generation γ-ray spectra indicate a structure change in deformed nuclei at about 6 MeV.

  19. Energy and Mass-Number Dependence of Hadron-Nucleus Total Reaction Cross Sections

    NASA Astrophysics Data System (ADS)

    Kohama, Akihisa; Iida, Kei; Oyamatsu, Kazuhiro

    2016-09-01

    We thoroughly investigate how proton-nucleus total reaction cross sections depend on the target mass number A and the proton incident energy. In doing so, we systematically analyze nuclear reaction data that are sensitive to nuclear size, namely, proton-nucleus total reaction cross sections and differential elastic cross sections, using a phenomenological black-sphere approximation of nuclei that we are developing. In this framework, the radius of the black sphere is found to be a useful length scale that simultaneously accounts for the observed proton-nucleus total reaction cross section and first diffraction peak in the proton elastic differential cross section. This framework, which is shown here to be applicable to antiprotons, is expected to be applicable to any kind of projectile that is strongly attenuated in the nucleus. On the basis of a cross-section formula constructed within this framework, we find that a less familiar A1/6 dependence plays a crucial role in describing the energy dependence of proton-nucleus total reaction cross sections.

  20. Investigations of nuclear structure and nuclear reactions induced by complex projectiles. Progress report, September 1, 1991--August 31, 1992

    SciTech Connect

    Sarantites, D.G.

    1992-12-01

    The research program described touches five areas of nuclear physics: nuclear structure studies at high spin (hyperdeformation in the mass A {approx_equal} 182 region, structure of {sup 182}Hg and {sup 182}Au at high spin, a highly deformed band in {sup 136}Pm and the anomalous h{sub 11/2} proton crossing in the A{approximately}135 superdeformed region), studies at the interface between structure and reactions (population of entry states in heavy-ion fusion reactions, nuclear structure effects in proton evaporation spectra, nuclear structure- dependent entry state population by total spectroscopy, entrance channel effects in fusion near the barrier, lifetimes of subbarrier {alpha} particles by the atomic clock method), production and study of hot nuclei (the statistical model evaporation code EVAP, statistical emission of deuterons and tritons from highly excited compound nuclei, heavy-fragment emission as a probe of the thermal properties of highly excited compound nuclei, use of incoming-wave boundary condition transmission coefficients in the statistical model: implications in the particle evaporation spectra, study of transparency in the optical model), reaction mechanism studies (binary character of highly dissipative {sup 209}Bi + {sup 136}Xe collisions at E/A=28.2 MeV), and development and use of novel techniques and instrumentation in these areas of research (including a 4{pi} channel selection device, a novel x-ray detector, and a simple channel-selecting detector).

  1. Investigations of nuclear structure and nuclear reactions induced by complex projectiles. [Dept. of Chemistry, Washington Univ. , St. Louis, Mo

    SciTech Connect

    Sarantites, D.G.

    1992-01-01

    The research program described touches five areas of nuclear physics: nuclear structure studies at high spin (hyperdeformation in the mass A [approx equal] 182 region, structure of [sup 182]Hg and [sup 182]Au at high spin, a highly deformed band in [sup 136]Pm and the anomalous h[sub 11/2] proton crossing in the A[approximately]135 superdeformed region), studies at the interface between structure and reactions (population of entry states in heavy-ion fusion reactions, nuclear structure effects in proton evaporation spectra, nuclear structure- dependent entry state population by total spectroscopy, entrance channel effects in fusion near the barrier, lifetimes of subbarrier [alpha] particles by the atomic clock method), production and study of hot nuclei (the statistical model evaporation code EVAP, statistical emission of deuterons and tritons from highly excited compound nuclei, heavy-fragment emission as a probe of the thermal properties of highly excited compound nuclei, use of incoming-wave boundary condition transmission coefficients in the statistical model: implications in the particle evaporation spectra, study of transparency in the optical model), reaction mechanism studies (binary character of highly dissipative [sup 209]Bi + [sup 136]Xe collisions at E/A=28.2 MeV), and development and use of novel techniques and instrumentation in these areas of research (including a 4[pi] channel selection device, a novel x-ray detector, and a simple channel-selecting detector).

  2. Low energy ion-molecule reaction dynamics and chemiionization kinetics

    NASA Astrophysics Data System (ADS)

    Farrar, J. M.

    Low energy crossed ion beam neutral beam studies of a wide spectrum of elementary chemical reactions were performed. The reactive scattering work embodies crossed beam studies of simple chemical processes under single collision conditions which elucidate reaction dynamics by measuring product branching ratios, translational energy distributions and scattering angle distributions. The studies have emphasized the proton transfer reactions of the important flame cations HCO(+) and H3O(+) with a number of neutral molecules present in flames, including H2O, CH3OH, CH3CH2OH, and (CH3)2CO, and a wide variety of reactions of the ground state carbon cation, C(+)((2)P), with neutrals, illustrating the important reactions of insertion into C-H, O-H, N-H, and C-C bonds, as well as condensation reactions in which new C-C bonds are formed, yielding significant increases in the molecular weight of the charged product. These studies represent the first crossed beam studies in which information more detailed than rate constants and energy dependent total cross sections was inferred about the reaction dynamics.

  3. Exclusive and Semi-Exclusive Reactions at a Higher Energy CEBAF

    SciTech Connect

    Carl Carlson

    1998-06-01

    More energy at CEBAF provides more opportunity for studies of hadron and nuclear properties. Many of the experiments that could be done are extensions of things already done at lower energies. Others represent new initiatives that could not work or could not theoretically be interpreted at lower energies. The author concentrates on the new initiatives, but do not wish our thinking to neglect what can be learned from continuations of lower energy work. The author begins with a list of some things that should be continued into a new energy regime. (1) Baryon and meson spectroscopy of higher mass states. With 4 GeV incoming electron energy, strange mesons are limited to 1.8 GeV in mass and charm is not producible. (2) Exclusive reactions, including meson and baryon form factors and reactions on few nucleon systems. The latter includes deuteron photodisintegration, the A and B form factors of the deuteron, and the deuteron tensor polarization T{sub 20}. (And we should not forget T{sub 20} in inclusive scattering.) (3) Hadrons in the nuclear medium, with such topics as color transparency, electroproduction of {rho} mesons, virtual Compton scattering off nuclei, and backward hadrons from e-d reactions. The very last must be especially important, since it gives the logo used in the advertizing for this conference. In addition, there are new initiatives that this talk will call attention to, in particular: (1) semi-exclusive meson production; (2) duality in semi-exclusive reactions; and (3) new views of exclusive reactions and perturbative QCD (leading to ''off-forward parton distributions'').

  4. Cross section measurements of deuteron induced nuclear reactions on natural titanium up to 34 MeV.

    PubMed

    Duchemin, C; Guertin, A; Haddad, F; Michel, N; Métivier, V

    2015-09-01

    Experimental cross sections for deuteron induced nuclear reactions on natural titanium were measured, using the stacked-foil technique and gamma spectrometry, up to 34 MeV with beams provided by the ARRONAX cyclotron. The experimental cross section values were monitored using the (nat)Ti(d,x)(48)V reaction, recommended by the IAEA. The excitation functions for (nat)Ti(d,x)(44m,46,47,48)Sc are presented and compared with the existing ones and with the TALYS 1.6 code calculations using default models. Our experimental values are in good agreement with data found in the literature. TALYS 1.6 is not able to give a good estimation of the production cross sections investigated in this work. These production cross sections of scandium isotopes fit with the new Coordinated Research Project (CRP) launched by the International Atomic Energy Agency (IAEA) to expand the database of monitor reactions. PMID:26103622

  5. Diffusive reaction dynamics on invariant free energy profiles.

    PubMed

    Krivov, Sergei V; Karplus, Martin

    2008-09-16

    A fundamental problem in the analysis of protein folding and other complex reactions in which the entropy plays an important role is the determination of the activation free energy from experimental measurements or computer simulations. This article shows how to combine minimum-cut-based free energy profiles (F(C)), obtained from equilibrium molecular dynamics simulations, with conventional histogram-based free energy profiles (F(H)) to extract the coordinate-dependent diffusion coefficient on the F(C) (i.e., the method determines free energies and a diffusive preexponential factor along an appropriate reaction coordinate). The F(C), in contrast to the F(H), is shown to be invariant with respect to arbitrary transformations of the reaction coordinate, which makes possible partition of configuration space into basins in an invariant way. A "natural coordinate," for which F(H) and F(C) differ by a multiplicative constant (constant diffusion coefficient), is introduced. The approach is illustrated by a model one-dimensional system, the alanine dipeptide, and the folding reaction of a double beta-hairpin miniprotein. It is shown how the results can be used to test whether the putative reaction coordinate is a good reaction coordinate. PMID:18772379

  6. Nuclear energy in a nuclear weapon free world

    SciTech Connect

    Pilat, Joseph

    2009-01-01

    The prospect of a nuclear renaissance has revived a decades old debate over the proliferation and terrorism risks of the use of nuclear power. This debate in the last few years has taken on an added dimension with renewed attention to disarmament. Increasingly, concerns that proliferation risks may reduce the prospects for realizing the vision of a nuclear-weapon-free world are being voiced.

  7. Study of nuclear reactions in laser plasmas at future ELI-NP facility

    NASA Astrophysics Data System (ADS)

    Lanzalone, G.; Altana, C.; Anzalone, A.; Cappuzzello, F.; Cavallaro, M.; Gizzi, L. A.; Labate, L.; Lamia, L.; Mascali, D.; Muoio, A.; Negoita, F.; Odorici, F.; Petrascu, H.; Trifirò, A.; Trimarchi, M.; Tudisco, S.

    2016-05-01

    In this contribution we will present the future activities that our collaboration will carry out at ELI-NP (Extreme Light Infrastructure Nuclear Physics), the new multi peta-watt Laser facility, currently under construction at Bucharest (Romania). The activities concerns the study of nuclear reactions in laser plasmas. In this framework we proposed the construction of a new, general-purpose experimental set-up able to detect and identify neutrons and charged particles.

  8. An efficient nonclassical quadrature for the calculation of nonresonant nuclear fusion reaction rate coefficients from cross section data

    NASA Astrophysics Data System (ADS)

    Shizgal, Bernie D.

    2016-08-01

    Nonclassical quadratures based on a new set of half-range polynomials, Tn(x) , orthogonal with respect to w(x) =e - x - b /√{ x } for x ∈ [ 0 , ∞) are employed in the efficient calculation of the nuclear fusion reaction rate coefficients from cross section data. The parameter b = B /√{kB T } in the weight function is temperature dependent and B is the Gamow factor. The polynomials Tn(x) satisfy a three term recurrence relation defined by two sets of recurrence coefficients, αn and βn. These recurrence coefficients define in turn the tridiagonal Jacobi matrix whose eigenvalues are the quadrature points and the weights are calculated from the first components of the eigenfunctions. For nonresonant nuclear reactions for which the astrophysical function can be expressed as a lower order polynomial in the relative energy, the convergence of the thermal average of the reactive cross section with this nonclassical quadrature is extremely rapid requiring in many cases 2-4 quadrature points. The results are compared with other libraries of nuclear reaction rate coefficient data reported in the literature.

  9. Global Nuclear Energy Partnership Programmatic Environmental Impact Statement

    SciTech Connect

    R.A. Wigeland

    2008-10-01

    Abstract: The proposed Global Nuclear Energy Partnership (GNEP) Program, which is part of the President’s Advanced Energy Initiative, is intended to support a safe, secure, and sustainable expansion of nuclear energy, both domestically and internationally. Domestically, the GNEP Program would promote technologies that support economic, sustained production of nuclear-generated electricity, while reducing the impacts associated with spent nuclear fuel disposal and reducing proliferation risks. The Department of Energy (DOE) proposed action envisions changing the United States nuclear energy fuel cycle from an open (or once-through) fuel cycle—in which nuclear fuel is used in a power plant one time and the resulting spent nuclear fuel is stored for eventual disposal in a geologic repository—to a closed fuel cycle in which spent nuclear fuel would be recycled to recover energy-bearing components for use in new nuclear fuel. At this time, DOE has no specific proposed actions for the international component of the GNEP Program. Rather, the United States, through the GNEP Program, is considering various initiatives to work cooperatively with other nations. Such initiatives include the development of grid-appropriate reactors and the development of reliable fuel services (to provide an assured supply of fresh nuclear fuel and assist with the management of the used fuel) for nations who agree to employ nuclear energy only for peaceful purposes, such as electricity generation.

  10. Chemical modeling of irreversible reactions in nuclear waste-water-rock systems

    SciTech Connect

    Wolery, T.J.

    1981-02-01

    Chemical models of aqueous geochemical systems are usually built on the concept of thermodynamic equilibrium. Though many elementary reactions in a geochemical system may be close to equilibrium, others may not be. Chemical models of aqueous fluids should take into account that many aqueous redox reactions are among the latter. The behavior of redox reactions may critically affect migration of certain radionuclides, especially the actinides. In addition, the progress of reaction in geochemical systems requires thermodynamic driving forces associated with elementary reactions not at equilibrium, which are termed irreversible reactions. Both static chemical models of fluids and dynamic models of reacting systems have been applied to a wide spectrum of problems in water-rock interactions. Potential applications in nuclear waste disposal range from problems in geochemical aspects of site evaluation to those of waste-water-rock interactions. However, much further work in the laboratory and the field will be required to develop and verify such applications of chemical modeling.

  11. Nuclear Energy Readiness Indicator Index (NERI): A benchmarking tool for assessing nuclear capacity in developing countries

    SciTech Connect

    Saum-Manning,L.

    2008-07-13

    Declining natural resources, rising oil prices, looming climate change and the introduction of nuclear energy partnerships, such as GNEP, have reinvigorated global interest in nuclear energy. The convergence of such issues has prompted countries to move ahead quickly to deal with the challenges that lie ahead. However, developing countries, in particular, often lack the domestic infrastructure and public support needed to implement a nuclear energy program in a safe, secure, and nonproliferation-conscious environment. How might countries become ready for nuclear energy? What is needed is a framework for assessing a country's readiness for nuclear energy. This paper suggests that a Nuclear Energy Readiness Indicator (NERI) Index might serve as a meaningful basis for assessing a country's status in terms of progress toward nuclear energy utilization under appropriate conditions. The NERI Index is a benchmarking tool that measures a country's level of 'readiness' for nonproliferation-conscious nuclear energy development. NERI first identifies 8 key indicators that have been recognized by the International Atomic Energy Agency as key nonproliferation and security milestones to achieve prior to establishing a nuclear energy program. It then measures a country's progress in each of these areas on a 1-5 point scale. In doing so NERI illuminates gaps or underdeveloped areas in a country's nuclear infrastructure with a view to enable stakeholders to prioritize the allocation of resources toward programs and policies supporting international nonproliferation goals through responsible nuclear energy development. On a preliminary basis, the indicators selected include: (1) demonstrated need; (2) expressed political support; (3) participation in nonproliferation and nuclear security treaties, international terrorism conventions, and export and border control arrangements; (4) national nuclear-related legal and regulatory mechanisms; (5) nuclear infrastructure; (6) the

  12. A program in medium-energy nuclear physics

    SciTech Connect

    Berman, B.L.; Dhuga, K.S.

    1990-01-01

    This report discusses the following topics: electron-scattering nuclear-structure studies; coincidence electrodisintegration studies of light nuclei; pion scattering and reactions on the three-body nuclei; and pion scattering from shell-model nuclei.

  13. The TDF System for Thermonuclear Plasma Reaction Rates, Mean Energies and Two-Body Final State Particle Spectra

    SciTech Connect

    Warshaw, S I

    2001-07-11

    The rate of thermonuclear reactions in hot plasmas as a function of local plasma temperature determines the way in which thermonuclear ignition and burning proceeds in the plasma. The conventional model approach to calculating these rates is to assume that the reacting nuclei in the plasma are in Maxwellian equilibrium at some well-defined plasma temperature, over which the statistical average of the reaction rate quantity {sigma}v is calculated, where {sigma} is the cross-section for the reaction to proceed at the relative velocity v between the reacting particles. This approach is well-understood and is the basis for much nuclear fusion and astrophysical nuclear reaction rate data. The Thermonuclear Data File (TDF) system developed at the Lawrence Livermore National Laboratory (Warshaw 1991), which is the topic of this report, contains data on the Maxwellian-averaged thermonuclear reaction rates for various light nuclear reactions and the correspondingly Maxwellian-averaged energy spectra of the particles in the final state of those reactions as well. This spectral information closely models the output particle and energy distributions in a burning plasma, and therefore leads to more accurate computational treatments of thermonuclear burn, output particle energy deposition and diagnostics, in various contexts. In this report we review and derive the theoretical basis for calculating Maxwellian-averaged thermonuclear reaction rates, mean particle energies, and output particle spectral energy distributions for these reactions in the TDF system. The treatment of the kinematics is non-relativistic. The current version of the TDF system provides exit particle energy spectrum distributions for two-body final state reactions only. In a future report we will discuss and describe how output particle energy spectra for three- and four-body final states can be developed for the TDF system. We also include in this report a description of the algorithmic implementation of the

  14. Energy straggling and radiation reaction for magnetic bremsstrahlung.

    NASA Technical Reports Server (NTRS)

    Shen, C. S.; White, D.

    1972-01-01

    Using the method of quantum electrodynamics, the energy distribution of particles and emitted photons is calculated for the case when increases in the average energy of the photon emitted by synchrotron radiation to values appreciable compared to the energy of the particle give rise to particle energy straggling and radiation spectrum broadening. The classical radiative reaction effects which may be tested in this type of experiment are outlined, and a detailed quantum mechanical calculation is presented. The significance of energy straggling in astrophysics is discussed briefly.

  15. Role of breakup and direct processes in deuteron-induced reactions at low energies

    NASA Astrophysics Data System (ADS)

    Avrigeanu, M.; Avrigeanu, V.

    2015-08-01

    Background: Recent studies of deuteron-induced reactions around the Coulomb barrier B pointed out that numerical calculations for deuteron-induced reactions are beyond current capabilities. The statistical model of nuclear reactions was used in this respect since the compound-nucleus (CN) mechanism was considered to be responsible for most of the total-reaction cross section σR in this energy range. However, specific noncompound processes such as the breakup (BU) and direct reactions (DR) should be also considered for the deuteron-induced reactions, making them different from reactions with other incident particles. Purpose: The unitary and consistent BU and DR consideration in deuteron-induced reactions is proved to yield results at variance with the assumption of negligible noncompound components. Method: The CN fractions of σR obtained by analysis of measured neutron angular distributions in deuteron-induced reactions on 27Al, 56Fe, 63,63Cu, and 89Y target nuclei, around B , are compared with the results of an unitary analysis of every reaction mechanism. The latter values have been supported by the previously established agreement with all available deuteron data for 27Al 54,56,-58,natCu, 63,65,natCu and 93Nb. Results: There is a significant difference between the larger CN contributions obtained from measured neutron angular distributions and calculated results of an unitary analysis of every deuteron-interaction mechanism. The decrease of the latter values is mainly due to the BU component. Conclusions: The above-mentioned differences underline the key role of the breakup and direct reactions that should be considered explicitly in the case of deuteron-induced reactions.

  16. Bibliographic survey of medium energy inclusive reaction data

    SciTech Connect

    Arthur, E.D.; Madland, D.G.; McClellan, D.M.

    1986-04-01

    A bibliographic survey of inclusive reaction data (experimental and theoretical) for several projectile types having energies between 50 and 1000 MeV has been completed. Approximately one thousand references selected from this survey describe the current state of knowledge for particle-induced inclusive reaction data. The search covered data for the following projectiles: p, d, t, /sup 3/He, /sup 4/He, and lithium ions.

  17. Evidence of nuclear reactions in the Pd lattice

    NASA Astrophysics Data System (ADS)

    Szpak, Stanislaw; Mosier-Boss, Pamela A.; Young, Charles; Gordon, Frank E.

    2005-08-01

    An operating Pd//D2O, Li+, Cl-//Pt cell, placed in an external electrostatic field, yielded unexpected results, viz. (i) Morphological changes in the form of discrete sites exhibiting molten-like features, i.e. features that require substantial energy expenditure. (ii) Presence of elements (Al, Mg, Ca, Si, Zn, ...) that could not be extracted from cell components and deposited on discrete sites. The cell design and the experimental protocol assuring reproducibility is described in detail.

  18. Deexcitation processes in nuclear reactions. [Dept. of Chemistry, Purdue Univ

    SciTech Connect

    Porile, N.T.

    1992-09-01

    During the past year, our research program has involved continuing analysis of Fermilab E-735, search for quark-gluon plasma (QGP) in {bar p}-p collisions; continuing study of target fragments produced in the interaction of copper with intermediate-energy heavy ions; an exclusive study of multifragmentation using reverse kinematics at the Bevalac; and detector development for the STAR detector at RHIC.

  19. Deexcitation processes in nuclear reactions. Annual progress report

    SciTech Connect

    Porile, N.T.

    1992-09-01

    During the past year, our research program has involved continuing analysis of Fermilab E-735, search for quark-gluon plasma (QGP) in {bar p}-p collisions; continuing study of target fragments produced in the interaction of copper with intermediate-energy heavy ions; an exclusive study of multifragmentation using reverse kinematics at the Bevalac; and detector development for the STAR detector at RHIC.

  20. Studies of nuclear reactions relevant to stellar or Big-Bang Nucleosynthesis using ICF plasmas at OMEGA

    NASA Astrophysics Data System (ADS)

    Zylstra, Alex; Herrmann, Hans; Kim, Yongho; Hale, Gerry; Paris, Mark; McEvoy, Aaron; Gatu Johnson, Maria; Frenje, Johan; Li, Chikang; Seguin, Fredrick; Sio, Hong; Petrasso, Richard; McNabb, Dennis; Sayre, Dan; Pino, Jesse; Brune, Carl; Bacher, Andy; Forrest, Chad; Glebov, Vladimir; Stoeckl, Christian; Janezic, Roger; Sangster, Craig

    2015-10-01

    The 3He+3He, T+3He, and p + D reactions directly relevant to Stellar or Big-Bang Nucleosynthesis (BBN) have been studied at the OMEGA laser facility using high-temperature low-density `exploding pusher' implosions. The advantage of using these plasmas is that they better mimic astrophysical systems than cold-target accelerator experiments. Measured proton spectra from the 3He3He reaction are used to constrain nuclear R-matrix modeling. The resulting T+3He gamma-ray data rule out an anomalously-high 6Li production during the Big Bang as an explanation to the high observed values in metal poor first generation stars. The proton spectrum from the T+3He reaction is also being used to constrain the R-matrix model. Recent experiments have probed the p + D reaction for the first time in a plasma; this reaction is relevant to energy production in protostars, brown dwarfs and at higher CM energies to BBN. This work was partially supported by the US DOE, NLUF, LLE, and GA.

  1. Studies of nuclear reactions relevant to stellar or Big-Bang Nucleosynthesis using ICF plasmas at OMEGA

    NASA Astrophysics Data System (ADS)

    Zylstra, Alex; Herrmann, Hans; Kim, Yongho; Hale, Gerry; Paris, Mark; McEvoy, Aaron; Gatu Johnson, Maria; Frenje, Johan; Li, Chikang; Seguin, Fredrick; Sio, Hong; Petrasso, Richard; McNabb, Dennis; Sayre, Dan; Pino, Jesse; Brune, Carl; Bacher, Andy; Forrest, Chad; Glebov, Vladimir; Stoeckl, Christian; Janezic, Roger; Sangster, Craig

    2015-11-01

    The 3He+3He, T+3He, and p +D reactions directly relevant to Stellar or Big-Bang Nucleosynthesis (BBN) have been studied at the OMEGA laser facility using high-temperature low-density `exploding pusher' implosions. The advantage of using these plasmas is that they better mimic astrophysical systems than cold-target accelerator experiments. Measured proton spectra from the 3He3He reaction are used to constrain nuclear R-matrix modeling. The resulting T+3He gamma-ray data rule out an anomalously-high 6Li production during the Big Bang as an explanation to the high observed values in metal poor first generation stars. The proton spectrum from the T+3He reaction is also being used to constrain the R-matrix model. Recent experiments have probed the p +D reaction for the first time in a plasma; this reaction is relevant to energy production in protostars, brown dwarfs and at higher CM energies to BBN. This work was partially supported by the US DOE, NLUF, LLE, and GA.

  2. Nuclear Energy, Nuclear Weapons Proliferation, and the Arms Race.

    ERIC Educational Resources Information Center

    Hollander, Jack, Ed.

    A symposium was organized to reexamine the realities of vertical proliferation between the United States and the Soviet Union and to place into perspective the horizontal proliferation of nuclear weapons throughout the world, including the possible role of commercial nuclear power in facilitating proliferation. The four invited symposium…

  3. Nuclear and Renewable Energy Synergies Workshop: Report of Proceedings

    SciTech Connect

    Ruth, M.; Antkowiak, M.; Gossett, S.

    2011-12-01

    Two of the major challenges the U.S. energy sector faces are greenhouse gas emissions and oil that is both imported and potentially reaching a peak (the point at which maximum extraction is reached). Interest in development of both renewable and nuclear energy has been strong because both have potential for overcoming these challenges. Research in both energy sources is ongoing, but relatively little research has focused on the potential benefits of combining nuclear and renewable energy. In September 2011, the Joint Institute for Strategic Energy Analysis (JISEA) convened the Nuclear and Renewable Energy Synergies Workshop at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to identify potential synergies and strategic leveraging opportunities between nuclear energy and renewable energy. Industry, government, and academic thought leaders gathered to identify potential broad categories of synergies and brainstorm topic areas for additional analysis and research and development (R&D). This report records the proceedings and outcomes of the workshop.

  4. Quantum Mechanical Free Energy Barrier for an Enzymatic Reaction

    NASA Astrophysics Data System (ADS)

    Rod, Thomas H.; Ryde, Ulf

    2005-04-01

    We discuss problems related to in silico studies of enzymes and show that accurate and converged free energy changes for complex chemical reactions can be computed if a method based on a thermodynamic cycle is employed. The method combines the sampling speed of molecular mechanics with the accuracy of a high-level quantum mechanics method. We use the method to compute the free energy barrier for a methyl transfer reaction catalyzed by the enzyme catechol O-methyltransferase at the level of density functional theory. The surrounding protein and solvent are found to have a profound effect on the reaction, and we show that energies can be extrapolated easily from one basis set and exchange-correlation functional to another. Using this procedure we calculate a barrier of 69 kJ/mol, in excellent agreement with the experimental value of 75 kJ/mol.

  5. Direct nuclear-pumped lasers using the He-3/n,p/H-3 reaction

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Jalufka, N. W.; Hohl, F.

    1978-01-01

    A description is presented of experimental results concerning a specific class of direct nuclear-pumped lasers classified as 'volumetric nuclear lasers'. In the considered laser system a fissioning gas, He-3, is mixed with the lasing gas to form a homogeneous mixture, resulting in uniform volume excitation. In typical volumetric nuclear lasers a fast-burst reactor is used as a source of neutrons which penetrate a polyethylene moderator. Here the fast neutrons are thermalized. After thermalization, neutrons scatter into the laser cell. Nuclear reactions produce a proton of 0.56 MeV and a tritium ion of 0.19. These ions produce secondary electrons which pump the laser medium creating a population inversion. The results reported demonstrate direct nuclear pumping of He-3-Ar, Xe, Kr, and Cl with the considered system.

  6. Monte Carlo studies of nuclear reactions and calculating hadron masses using different methods with consistent results

    NASA Astrophysics Data System (ADS)

    Roncaglia, Renato

    Scattering reactions are ordinarily solved by performing a partial-wave decomposition of the scattering amplitude, and solving coupled-channel equations for each partial wave. As the energy increases, the number of partial waves and the number of equations for partial waves also increases, making the method unpractical. We study nuclear reactions without performing a partial wave expansion of the potential, by solving a Lippmann- Schwinger equation in momentum space with Monte Carlo techniques. We study the problem of the convergence of the Born series with the use of Pade acceleration in the presence of Monte-Carlo-generated noise by solving for Tabakin's potential, whose analytic solution is known. We also investigate how Pade-acceleration can handle the case of a weak nuclear potential in a strong Coulomb interaction by solving for a potential of the type proposed by Kisslinger for low-energy /pi - 12C interactions. The spectra of mesons and baryons show striking regularities, which can be explained in terms of some general properties of the quark-quark interactions. Without assuming any specific form for the Hamiltonian, we show that it is possible to take advantage of these regularities to obtain constraints on the constituent quark mass differences, and to predict the masses of some hadrons not yet observed experimentally. In particular, we predict the value of the mass of the Bc* meson. With the help of semi-empirical mass formulas which estimate the effect of color-magnetic interactions, we obtain sum-rules relating the masses of hadrons. These mass formulas can be used to predict the masses of several baryons not yet observed. Information on color-triplet and color-singlet interactions gathered respectively from the baryon and meson spectra can be used in determining the masses of exotic tetraquarks composed of color-triplet diquarks. All of our predictions yield exotic masses far above threshold for strong decay, therefore making experimental observation

  7. Theoretical interpretation of high-energy nuclear collisions.

    SciTech Connect

    Fai, G.

    1992-06-01

    Nuclear collisions are interpreted theoretically. The nuclear equation of state is studied in a wide energy range. Subnucleonic degrees of freedom are invoked at high energy densities and at short length-scales. Questions of dynamical collision simulations are investigated. Direct support is provided for experiment in the form of collaborative projects. The major objective of this nuclear theory program is a better understanding of the properties of strongly interacting matter on the nuclear energy scale, as manifested in high-energy heavy-ion collisions.

  8. Energy recovery linacs in high-energy and nuclear physics

    SciTech Connect

    I. Ben-Zvi; Ya. Derbenev; V. Litvinenko; L. Merminga

    2005-03-01

    Energy Recovery Linacs (ERL) have significant potential uses in High Energy Physics and Nuclear Physics. We describe some of the potential applications which are under development by our laboratories in this area and the technology issues that are associated with these applications. The applications that we discuss are electron cooling of high-energy hadron beams and electron-nucleon colliders. The common issues for some of these applications are high currents of polarized electrons, high-charge and high-current electron beams and the associated issues of High-Order Modes. The advantages of ERLs for these applications are numerous and will be outlined in the text. It is worth noting that some of these advantages are the high-brightness of the ERL beams and their relative immunity to beam-beam disturbances.

  9. Nuclear and High-Energy Astrophysics

    NASA Astrophysics Data System (ADS)

    Weber, Fridolin

    2003-10-01

    There has never been a more exciting time in the overlapping areas of nuclear physics, particle physics and relativistic astrophysics than today. Orbiting observatories such as the Hubble Space Telescope, Rossi X-ray Timing Explorer (RXTE), Chandra X-ray satellite, and the X-ray Multi Mirror Mission (XMM) have extended our vision tremendously, allowing us to see vistas with an unprecedented clarity and angular resolution that previously were only imagined, enabling astrophysicists for the first time ever to perform detailed studies of large samples of galactic and extragalactic objects. On the Earth, radio telescopes (e.g., Arecibo, Green Bank, Parkes, VLA) and instruments using adaptive optics and other revolutionary techniques have exceeded previous expectations of what can be accomplished from the ground. The gravitational wave detectors LIGO, LISA VIRGO, and Geo-600 are opening up a window for the detection of gravitational waves emitted from compact stellar objects such as neutron stars and black holes. Together with new experimental forefront facilities like ISAC, ORLAND and RIA, these detectors provide direct, quantitative physical insight into nucleosynthesis, supernova dynamics, accreting compact objects, cosmic-ray acceleration, and pairproduction in high energy sources which reinforce the urgent need for a strong and continuous feedback from nuclear and particle theory and theoretical astrophysics. In my lectures, I shall concentrate on three selected topics, which range from the behavior of superdense stellar matter, to general relativistic stellar models, to strange quark stars and possible signals of quark matter in neutron stars.

  10. Molten salts and nuclear energy production

    NASA Astrophysics Data System (ADS)

    Le Brun, Christian

    2007-01-01

    Molten salts (fluorides or chlorides) were considered near the beginning of research into nuclear energy production. This was initially due to their advantageous physical and chemical properties: good heat transfer capacity, radiation insensitivity, high boiling point, wide range solubility for actinides. In addition it was realised that molten salts could be used in numerous situations: high temperature heat transfer, core coolants with solid fuels, liquid fuel in a molten salt reactor, solvents for spent nuclear solid fuel in the case of pyro-reprocessing and coolant and tritium production in the case of fusion. Molten salt reactors, one of the six innovative concepts chosen by the Generation IV international forum, are particularly interesting for use as either waste incinerators or thorium cycle systems. As the neutron balance in the thorium cycle is very tight, the possibility to perform online extraction of some fission product poisons from the salt is very attractive. In this article the most important questions that must be addressed to demonstrate the feasibility of molten salt reactor will be reviewed.

  11. Using the sound of nuclear energy

    DOE PAGES

    Garrett, Steven; Smith, James; Smith, Robert; Heidrich, Benden; Heibel, Michael

    2016-08-01

    The generation of sound by heat has been documented as an “acoustical curiosity” since a Buddhist monk reported the loud tone generated by a ceremonial rice-cooker in his diary, in 1568. Over the last four decades, significant progress has been made in understanding “thermoacoustic processes,” enabling the design of thermoacoustic engines and refrigerators. Motivated by the Fukushima nuclear reactor disaster, we have developed and tested a thermoacoustic engine that exploits the energy-rich conditions in the core of a nuclear reactor to provide core condition information to the operators without a need for external electrical power. The heat engine is self-poweredmore » and can wirelessly transmit the temperature and reactor power level by generation of a pure tone which can be detected outside the reactor. We report here the first use of a fission-powered thermoacoustic engine capable of serving as a performance and safety sensor in the core of a research reactor and present data from the hydrophones in the coolant (far from the core) and an accelerometer attached to a structure outside the reactor. These measurements confirmed that the frequency of the sound produced indicates the reactor’s coolant temperature and that the amplitude (above an onset threshold) is related to the reactor’s operating power level. Furthermore, these signals can be detected even in the presence of substantial background noise generated by the reactor’s fluid pumps.« less

  12. Building a Universal Nuclear Energy Density Functional (UNEDF): SciDAC-2 Project

    SciTech Connect

    Carlson, Joe; Furnstahl, Dick; Lusk, Rusty; Nazarewicz, Witek; Ng, Esmond; Thompson, Ian; Vary, James

    2012-06-30

    An understanding of the properties of atomic nuclei is crucial for a complete nuclear theory, for element formation, for properties of stars, and for present and future energy and defense applications. During the period of Dec. 1, 2006 - Jun. 30, 2012, the UNEDF collaboration carried out a comprehensive study of all nuclei based on the most accurate knowledge of the strong nuclear interaction, the most reliable theoretical approaches, the most advanced algorithms, and extensive computational resources, with a view towards scaling to the petaflop platforms and beyond. The long-term vision initiated with UNEDF is to arrive at a comprehensive, quantitative, and unified description of nuclei and their reactions, grounded in the fundamental interactions between the constituent nucleons. We seek to replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that delivers maximum predictive power with well-quantified uncertainties. Specifically, the mission of this project has been three-fold: first, to find an optimal energy density functional (EDF) using all our knowledge of the nucleonic Hamiltonian and basic nuclear properties; second, to apply the EDF theory and its extensions to validate the functional using all the available relevant nuclear structure and reaction data; and third, to apply the validated theory to properties of interest that cannot be measured, in particular the properties needed for reaction theory.

  13. Refined scenario of standard Big Bang nucleosynthesis allowing for nonthermal nuclear reactions in the primordial plasma

    SciTech Connect

    Voronchev, Victor T.; Nakao, Yasuyuki; Nakamura, Makoto; Tsukida, Kazuki

    2012-11-12

    The standard scenario of big bang nucleosynthesis (BBN) is generalized to take into account nonthermal nuclear reactions in the primordial plasma. These reactions are naturally triggered in the BBN epoch by fast particles generated in various exoergic processes. It is found that, although such particles can appreciably enhance the rates of some individual reactions, their influence on the whole process of element production is not significant. The nonthermal corrections to element abundances are obtained to be 0.1% ({sup 3}H), -0.03% ({sup 7}Li), and 0.34 %-0.63% (CNO group).

  14. Decay heat studies for nuclear energy

    NASA Astrophysics Data System (ADS)

    Algora, A.; Jordan, D.; Taín, J. L.; Rubio, B.; Agramunt, J.; Caballero, L.; Nácher, E.; Perez-Cerdan, A. B.; Molina, F.; Estevez, E.; Valencia, E.; Krasznahorkay, A.; Hunyadi, M. D.; Gulyás, J.; Vitéz, A.; Csatlós, M.; Csige, L.; Eronen, T.; Rissanen, J.; Saastamoinen, A.; Moore, I. D.; Penttilä, H.; Kolhinen, V. S.; Burkard, K.; Hüller, W.; Batist, L.; Gelletly, W.; Nichols, A. L.; Yoshida, T.; Sonzogni, A. A.; Peräjärvi, K.

    2014-01-01

    The energy associated with the decay of fission products plays an important role in the estimation of the amount of heat released by nuclear fuel in reactors. In this article we present results of the study of the beta decay of some refractory isotopes that were considered important contributors to the decay heat in reactors. The measurements were performed at the IGISOL facility of the University of Jyväskylä, Finland. In these studies we have combined for the first time a Penning trap (JYFLTRAP), which was used as a high resolution isobaric separator, with a total absorption spectrometer. The results of the measurements as well as their consequences for decay heat summation calculations are discussed.

  15. Proceedings of GLOBAL 2013: International Nuclear Fuel Cycle Conference - Nuclear Energy at a Crossroads

    SciTech Connect

    2013-07-01

    The Global conference is a forum for the discussion of the scientific, technical, social and regulatory aspects of the nuclear fuel cycle. Relevant topics include global utilization of nuclear energy, current fuel cycle technologies, advanced reactors, advanced fuel cycles, nuclear nonproliferation and public acceptance.

  16. Development of Nuclear Reaction Data Retrieval System on IntelligentPad by JCPRG

    SciTech Connect

    Aoyama, Shigeyoshi; Masui, Hiroshi; Ohkubo, Michimasa; Arai, Koji; Ohbayasi, Yosihide; Kato, Kiyoshi; Chiba, Masaki

    2005-05-24

    A newly designed retrieval system of nuclear reaction data is developed on the IntelligentPad architecture, which is called CONTIP. We designed the network-base retrieval system. The relational database is constructed on the UNIX server and the retrieval interface is constructed on the Windows PC. We applied it for NRDF and Exfor compilations as an application example.

  17. Cross-checking of Large Evaluated and Experimental Nuclear Reaction Databases

    SciTech Connect

    Zeydina, O.; Koning, A.J.; Soppera, N.; Raffanel, D.; Bossant, M.; Dupont, E.; Beauzamy, B.

    2014-06-15

    Automated methods are presented for the verification of large experimental and evaluated nuclear reaction databases (e.g. EXFOR, JEFF, TENDL). These methods allow an assessment of the overall consistency of the data and detect aberrant values in both evaluated and experimental databases.

  18. Investigation on energy conversion technology using biochemical reaction elements, 2

    NASA Astrophysics Data System (ADS)

    1994-03-01

    For measures taken for resource/energy and environmental issues, a study is made on utilization of microbial biochemical reaction. As a reaction system using chemical energy, cited is production of petroleum substitution substances and food/feed by CO2 fixation using hydrogen energy and hydrogen bacteria. As to photo energy utilization, regarded as promising are CO2 fixation using photo energy and microalgae, and production of hydrogen and useful carbon compound using photosynthetic organisms. As living organism/electric energy interconversion, cited is the culture of chemoautotrophic bacteria which fix CO2 using electric energy. For enhancing its conversion efficiency, it is important to develop a technology of gene manipulation of the bacteria and a system to use functional biochemical elements adaptable to the electrode reaction. With regard to utilization of the microorganism metabolic function, the paper presents emission of soluble nitrogen in the hydrosphere into the atmosphere using denitrifying bacteria, removal of phosphorus, reduction in environmental pollution caused by heavy metal dilute solutions, and recovery as resources, etc.

  19. Kinematics of Eley-Rideal Reactions at Hyperthermal Energies

    NASA Astrophysics Data System (ADS)

    Yao, Yunxi; Giapis, Konstantinos P.

    2016-06-01

    Direct or Eley-Rideal reactions between energetic N+ and O+ projectiles and O atoms, adsorbed onto Pt and Pd surfaces, are studied experimentally at incidence energies between 20 and 200 eV. The exit energies of the diatomic molecular products NO and O2 depend linearly on the incidence energy of the corresponding projectiles. A reaction mechanism is proposed, where the incident projectile collides with a single metal atom on the surface, linked to an adsorbed O atom. At the apsis point, a high-energy transient state is formed between the projectile, substrate, and adsorbate atoms. As the projectile begins to rebound, the transient state decomposes into a diatomic molecule, consisting of the original projectile and the adsorbed O atom, which exits the surface with memory of the incidence energy. Energy and momentum conservation during this single-bounce event (atom in, molecule out) accurately predict the exit energy of the molecular product, thus capturing the kinematics of the direct reaction.

  20. Calculation of reaction energies and adiabatic temperatures for waste tank reactions

    SciTech Connect

    Burger, L.L.

    1993-03-01

    Continual concern has been expressed over potentially hazardous exothermic reactions that might occur in underground Hanford waste tanks. These tanks contain many different oxidizable compounds covering a wide range of concentrations. Several may be in concentrations and quantities great enough to be considered a hazard in that they could undergo rapid and energetic chemical reactions with nitrate and nitrite salts that are present. The tanks also contain many inorganic compounds inert to oxidation. In this report the computed energy that may be released when various organic and inorganic compounds react is computed as a function of the reaction mix composition and the temperature. The enthalpy, or integrated heat capacity, of these compounds and various reaction products is presented as a function of temperature, and the enthalpy of a given mixture can then be equated to the energy release from various reactions to predict the maximum temperature that may be reached. This is estimated for several different compositions. Alternatively, the amounts of various diluents required to prevent the temperature from reaching a critical value can be estimated.