Gamow-Teller strength in the β-decay of 36Ca
International Nuclear Information System (INIS)
Trinder, W.; Adelberger, E.G.; Janas, Z.; Keller, H.; Krumbholz, K.; Pfuetzner, M.; Rykaczewski, K.
1994-11-01
The β-decay of 36 Ca has been studied at the projectile fragment separator at GSI Darmstadt. The Gamow-Teller strength function B(GT), deduced from the observed β-delayed proton- and γ-emission and from the measured half-life of 102(2) ms, is compared to results obtained from large-scale sd-shell model calculations. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Deloncle, I. [CSNSM, CNRS et Universite Paris-Sud, Orsay (France); CEA, DAM, DIF, Arpajon (France); Peru, S. [CEA, DAM, DIF, Arpajon (France); Martini, M. [ESNT, CEA-Saclay, DSM, Irfu, Service de Physique Nucleaire, Gif-sur-Yvette (France)
2017-08-15
In this paper we present theoretical results on the dipole response in the proton spin-saturated {sup 90-94}Zr isotopes. The electric and magnetic dipole excitations are obtained in Hartree-Fock-Bogolyubov plus Quasi-particle Random Phase Approximation (QRPA) calculations performed with the D1M Gogny force. A pnQRPA charge exchange code is used to study the Gamow-Teller response. The results on the pygmy, the giant dipole resonances as well as those on the magnetic nuclear spin-flip excitation and the Gamow-Teller transitions are compared with available experimental or theoretical information. In our approach, the proton pairing plays a role in the phonon excitations, in particular in the M1 nuclear spin-flip resonance. (orig.)
Gamow teller strength from n-nucleus scattering
International Nuclear Information System (INIS)
Haeusser, O.
1989-08-01
Detailed studies of the spin-isospin structure of nuclear excitations are possible at TRIUMF's medium resolution spectrometer using the (n,p), ( p → , p →/ and (p,n) reactions. We discuss here results on isospin symmetry of inelastic nucleon scattering reactions populating isospin triads in A=6 and A=12 nuclei. The empirical ratio of L=0 isovector spin flip cross sections at 200-450 MeV and B(GT) for strong Gamow-Teller transitions in p-shell nuclei is found to be larger than calculated in the DWIA using a free NN t-matrix. Based on empirical values of σ/B(GT) the β + Gamow Teller strength function from (n,p) reactions on (sd) and (fp) shell targets is substantially quenched compared to current nuclear structure models using the free-nucleon axial-vector coupling constant. (Author) 33 refs., 6 figs
Gamow-Teller Strength Distributions for Some Magic Nuclei
Directory of Open Access Journals (Sweden)
Necla ÇAKMAK
2014-12-01
Full Text Available The total Gamow-Teller strengths and their energy distributions for 96Zr, 96Sr, 54Ca, 28O, 24C and 14C have been obtained within the framework of Random Phase Approximation (RPA. The effective interaction potential has been described by considering the commutativity of the Gamow-Teller operator with the central part of the nuclear Hamiltonian.
Gamow-Teller decay of T = 1 nuclei to odd-odd N = Z nuclei
Energy Technology Data Exchange (ETDEWEB)
Lisetskiy, A F [National Superconducting Cyclotron Laboratory, MSU, East Lansing, MI 48824 (United States); Gelberg, A [Institute for Nuclear Physics, University of Cologne, 50937 Cologne (Germany); Institute of Physical and Chemical Reasearch (RIKEN), Wako, 351-0198 (Japan); Brentano, P von [Institute for Nuclear Physics, University of Cologne, 50937 Cologne (Germany)
2005-01-01
Transition strengths of Gamow-Teller decay of T{sub z} = {+-}1 nuclei to N = Z odd-odd nuclei have been calculated in a two-nucleon approximation for spherical and deformed nuclei. The results obtained for the latter are quite close to the values obtained by full-space shell-model calculations and to the experiment.
Gamow-teller transitions: progress and problems
International Nuclear Information System (INIS)
Walter, G.
1994-01-01
The determination of the Gamow-Teller (GT) matrix elements from beta-decay and charge exchange reactions has led to a series of discoveries concerning the structure of the nucleus and the properties of spin-isospin transitions in nuclei. The study of GT distribution and strength, either by charge exchange or weak decay, provides excellent tests for nuclear models as these parameters are extremely sensitive to the details of nuclear structure. Recent improvements of these models have reduced, for the most part, differences between experiment and theory, allowing in turn a more reliable estimate of weak decay rates in stellar matter. A better understanding of the 'missing strength' and of the failure of many experiments to detect the strength that is present have also been obtained. Recently, it appears also that weak decay studies in selected region (proton or neutron rich) of the N-Z plane give access to the GT giant resonance. (J.S.). 65 refs., 10 figs
Role of the momentum transfer in the quenching of the Gamow-Teller strength
Energy Technology Data Exchange (ETDEWEB)
Marketin, Tomislav [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany); Physics Department, Faculty of Science, University of Zagreb (Croatia); Martinez-Pinedo, Gabriel [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany); Paar, Nils; Vretenar, Dario [Physics Department, Faculty of Science, University of Zagreb (Croatia)
2012-07-01
A fully consistent calculation of the Gamow-Teller strength is presented, based on a microscopic theoretical framework. Nuclear ground state is determined using the relativistic Hartree-Bogolyubov (RHB) model with density dependent meson-nucleon coupling constants, and transition rates are calculated via proton-neutron relativistic quasiparticle RPA using the same interaction as in the RHB equations. The (p,n) probe has a similar spin-isospin operator structure to the Gamow-Teller (GT) operator. However, they become comparable only if the GT cross section is measured at a very small momentum transfer q. At higher momentum transfer the isovector spin monopole (IVSM) mode occurs, with the r{sup 2}{sigma}{tau} transition operator. Unlike the Gamow-Teller operator which excites only the 0{Dirac_h}{omega} transitions, the isovector spin monopole operator can also excite 2{Dirac_h}{omega} transitions and can change the strength distribution at high excitation energies. We explore the strength beyond the resonance, examine the effect of momentum transfer on the total strength and compare the results with recent measurements.
Gamow-Teller beta decay of proton-rich nuclei
International Nuclear Information System (INIS)
Klepper, O.; Rykaczewski, K.
1990-11-01
The beta decays of 48 Mn and of even-even nuclei near the double shell-closures at 100 Sn and 146 Gd are currently investigated at the GSI on-line mass separator. Their Gamow-Teller strength are surveyed in their present experimental status, together with related results from the ISOLDE (CERN) and ISOCELE (Orsay) separators, and are compared with predictions from different nuclear models. The strength of the 0 + → 1 + Gamow-Teller transitions is compiled in tables and graphs. (orig.)
Gamow-Teller strength in the continuum studied via the (p,n) reaction
International Nuclear Information System (INIS)
Wakasa, T.; Hatanaka, K.; Sakai, H.
2002-01-01
The double differential cross sections for θ lab between 0.0deg and 14.7deg and the polarization transfer coefficient D NN (0deg) for the 27 Al (p vector, n vector) reaction have been measured at a bombarding energy of 295 MeV. A multipole decomposition technique is applied for the cross section data to extract L=0, 1, 2, and 3 contributions. The Gamow-Teller (GT) strength B(GT) deduced from the L=0 contribution is compared with the B(GT) values calculated in a full sd shell-model space. The sum of B(GT) values up to 20 MeV excitation is S β- =4.0 ± 0.1 ± 0.1. A fairly large L=0 contribution is observed in the continuum region up to 50 MeV, which could be in part ascribed to the quenched GT strength. A limit on the effect that the Δ(1232)-isobar nucleon-hole admixture has upon the GT strength is estimated. (author)
International Nuclear Information System (INIS)
Klapdor, H.V.
1976-01-01
Recent results in β-delayed neutron emission are interpreted by structure of the Gamow-Teller giant resonance not included in the 'gross-theory' of β-decay. Inclusion of this structure of the β-decay function is important for calculations of β-decay production rates for heavy nuclides by astrophysical processes and thermonuclear explosions. (Auth.)
International Nuclear Information System (INIS)
Mathews, G.J.; Bloom, S.D.; Hausman, R.F. Jr.
1983-01-01
Shell-model calculations of the Gamow-Teller strength function for 90 Zr have been performed utilizing a realistic finite-range two-body interaction in a model space consisting of the 2p and 1g shells. The effects of admixtures of two-particle two-hole excitations in 90 Nb, mostly due to the spin and isospin exchange components of the nucleon-nucleon force, are discussed. Ground state correlations in 90 Zr are also added via seniority-zero two-proton excitations from the 2p shell into the 1g/sub 9/2/ shell. With the correlations the Gamow-Teller strength function is in good agreement with the experimental results and accounts for essentially all of the observed dispersion of strength. The inclusion of these correlations does not, however, produce either a displacement of Gamow-Teller strength to higher excitation energies, or a significant change in the total strength. Thus, they cannot account for the observed Gamow-Teller quenching. The quenching factor derived by a comparison of our calculated results with experiment is 0.52
Gamow-Teller strength distributions and electron capture rates for 55Co and 56Ni
International Nuclear Information System (INIS)
Nabi, Jameel-Un; Rahman, Muneeb-Ur
2005-01-01
The Gamow-Teller strength (GT) distributions and electron capture rates on 55 Co and 56 Ni have been calculated using the proton-neutron quasiparticle random phase approximation theory. We calculate these weak interaction mediated rates over a wide temperature (0.01x10 9 -30x10 9 K) and density (10-10 11 gcm -3 ) domain. Electron capture process is one of the essential ingredients involved in the complex dynamics of supernova explosion. Our calculations of electron capture rates show differences with the reported shell model diagonalization approach calculations and are comparatively enhanced at presupernova temperatures. We note that the GT strength is fragmented over many final states
Chiral filter, axial charges and Gamow-Teller strengths
International Nuclear Information System (INIS)
Rho, M.
1983-09-01
The different ways that nuclear matter responds to the weak axial-vector current are interpreted in terms of modification of the ''vacuum'' in baryon-rich environments. The notion of ''chiral filter'' is introduced. Use of a ward identity is suggested. The Gamow-Teller quenching and the enhanced axial charge in O + O - transitions follow from this. I also discuss briefly possible relevance of the nucleon as a topological soliton configuration to the global property of nuclear axial response functions
International Nuclear Information System (INIS)
Neumann-Cosel, P. von; Byelikov, A.; Richter, A.; Shevchenko, A.; Adachi, T.; Fujita, Y.; Shimbara, Y.; Fujita, H.; Heger, A.; Kolbe, E.; Langanke, K.; Martinez-Pinedo, G.
2006-01-01
Some aspects of the importance of neutrino-induced reactions on nuclei within supernova physics are discussed. It is argued that important constraints on the experimentally unknown cross sections can be obtained from experimental studies of the nuclear response in selected cases. Examples are neutral-current induced reactions on fp-shell nuclei extracted from high-resolution inelastic electron scattering data providing the M1 strength distributions and the production of the exotic heavy, odd-odd nuclei 138La and 180Ta through charged-current reactions dominated by Gamow-Teller transitions. The Gamow-Teller strength can deduced from the (3He,t) charge-exchange reaction at zero degree
The beta-decay of 48Mn: improved data on Gamow-Teller quenching
International Nuclear Information System (INIS)
Szerypo, J.; Bazin, D.; Brown, B.A.
1991-01-01
Beta-decay studies of very proton-rich nuclides allow to investigate the phenomenon of quenching of Gamow-Teller transitions. A presentation of the experimental techniques is followed by the discussion of preliminray results of the measurements in comparison to shell-model calculations. A corresponding reinvestigation is discussed. A mass-separated 48 Mn beam was used from 12 C( 40 Ca,p3n) reactions. The 48 Mn decay spectroscopy was performed simultaneously in two beam lines of the mass separator. (G.P.) 13 refs.; 2 figs
Gamow Teller strength from charge exchange reactions at intermediate energies
International Nuclear Information System (INIS)
Haeusser, O.
1989-07-01
Detailed studies of the spin-isospin structure of nuclear excitations are possible at TRIUMF's medium resolution spectrometer using the (n,p), ( p → , p →/ ) and (p,n) reactions. We discuss here results on isospin symmetry of inelastic nucleon scattering reactions populating isospin triads in A=6 and A=12 nuclei. The β + Gamow Teller strength function from (n,p) reactions on (sd) and (fp) shell targets is found to be substantially quenched compared to current nuclear structure models using the free-nucleon axial-vector coupling constant. (Author) 22 refs., 3 figs
Characteristics of the Gamow-Teller Force in the β- Decay of 40Zr98
International Nuclear Information System (INIS)
Raden Oktova
2002-01-01
The characteristics of the β - decay force for the Gamow-Teller transition in the p-h and the p-p channels in the heavy neutron-rich nucleus 40 Zr 98 have been studied. The ground state single-particle levels in the parent nucleus were calculated self-consistently using the Fayans energy-density functional, and from them the quasi-particle basis was obtained using the BCS model. The residual charge-changing force responsible for the β - transition was taken as having a zero-range (a delta function); in the p-h channel the spin-isospin exchange → σ 1 . → σ 2 → τ 1 . → τ 2 term in the Migdal-Larkin force was used, and that in the p-p channel was a constant. The method employed was the proton-neutron QRPA (pnQRPA). The results show that the proton-neutron pairing p-p force in the Gamow-Teller decay is negligible for the nucleus considered. The value of the p-h force obtained is g ' = 0.735, slightly larger than the standard value of g ' = 0.7 commonly used for stable nuclei. (author)
Gamow-Teller Strengths from (3He,t) Charge-Exchange Reaction
International Nuclear Information System (INIS)
Fujita, Yoshitaka
2006-01-01
Gamow-Teller (GT) transition is the most popular nuclear weak process with the nature of spin-isospin excitation. GT transitions in pf-shell nuclei, including those starting from unstable nuclei, are of interest, due to their importance in astrophysical processes. Weak processes, however, gives us rather limited information on the GT response of nuclei. We introduce high-resolution ( 3 He, t) reaction at 0 0 and at an intermediate beam energy as a new spectroscopic tool for studying GT excitations. Owing to the high energy-resolution of the reaction (∼ 30 keV), individual transitions can be observed up to the region of GT giant resonance. Assuming isospin symmetry for the T z = ±1 → 0 isobaric analogous transitions in isobars with mass number A, we present a new method to deduce GT transition strengths starting from proton rich exotic nuclei
Gamow-Teller matrix elements from 00 ( p,n) cross section
International Nuclear Information System (INIS)
Goodman, C.D.; Goulding, C.A.; Greenfield, M.B.; Rapaport, J.; Bainum, D.E.; Foster, C.C.; Love, W.G.; Petrovich, F.
1980-01-01
After simple corrections for distortion effects, 120-MeV, 0 0 (p,n) cross sections are found to be proportional to the squares of the corresponding Fermi and Gamow-Teller matrix elements extracted from β-decay measurements. It is suggested that this proportionality can be used to extract Gamow-Teller matrix elements for transitions inaccessible to β decay
Gamow-Teller strength functions from (→p,→p') scattering experiments
International Nuclear Information System (INIS)
Hausser, O.
1987-01-01
We present here recent (→p, →'p) results from TRIUMF that are relevant to the determination of spin-flip isovector strength functions in nuclei. Distortion factors needed for the extraction of nuclear-structure information have been deduced from cross sections and analyzing powers in elastic scattering for several energies and targets. Nonrelativistic optical potentials obtained by folding effective nucleon (N)-nucleus interactions with nuclear densities are found to overpredict both elastic and reaction cross sections, whereas Dirac calculations that include Pauli blocking are in good agreement with the data. Spin observables (S nn and A y ) for the quasi-elastic region in 54 Fe(→p, →p) at 290 MeV provide some evidence for the reduction of the effective proton mass predicted in relativistic mean-field theories as a consequence of the attractive scalar field in the nuclear medium. The energy dependence of the effective N-nucleus interaction at small momentum transfers has been investigated using isoscalar and isovector 1 + states in 28 Si as probe states. We find that the cross sections for the isovector transitions are in good agreement with predictions for the dominant Vστ part of the Franey-Love interaction. Gamow-Teller (GT) strength functions have been obtained in 24 Mg and 54 Fe from measurements of both cross sections and spin-flip probabilities S nn . The spin-flip cross sections σS nn are particularly useful in heavier nuclei to discriminate against a continuous background of ΔS = 0 excitations. In the (s, d) shell where full shell-model wave functions are available, the GT quenching factors (g A eff / g A free ) 2 ≅ 0.7 are in good agreement with those from recent (p, n) and (n, p) experiments. We show that a state-by-state comparison of (p, p') and (e, e') results has the potential of identifying pionic current contributions in (e, e'). The GT quenching factors in 54 Fe are smaller than in the (s, d) shell probably because of severely
Effect on Tensor Correlations on Gamow- Teller States in 90Zr and 208Pb
International Nuclear Information System (INIS)
Bai, C. L.; Sagawa, H.; Zhang, H. Q.
2009-01-01
The tensor terms of the Skyrme effective interaction are included in the self-consistent Hartree-Fock plus Random Phase Approximation (HF-RPA) model. The Gamow-Teller (GT) strength function of 9 0Z r and 2 08P b are calculated with and without the tensor terms. The main peaks are moved downwards by about 2 MeV when including the tensor contribution. About 10% of the non-energy weighted sum rule is shifted to the excitation energy region above 30 MeV by the RPA tensor correlations. The contribution of the tensor terms to the energy weighted sum rule is given analytically, and compared to the outcome of RPA. A microscopic origin of the quenching of GT sum rule is discussed in relation with the coupling to giant spin-quadrupole excitations by the tensor interactions.(author)
Effect of Tensor Correlations on Gamow-Teller States in 90Zr and 208Pb
International Nuclear Information System (INIS)
Bai, C. L.; Zhang, H. Q.; Zhang, X. Z.
2009-01-01
The tensor terms of the Skyrme effective interaction are included in the self-consistent Hartree-Fock plus Random Phase Approximation (HF-RPA) model. The Gamow-Teller (GT) strength functions of 9 0Z r and 2 08P b is calculated with and without the tensor terms. The main peaks are moved downwards by about 2 MeV when including the tensor contribution. About 10% of the non-energy weighted sum rule is shifted to the excitation energy region above 30 MeV by the RPA tensor correlations. The contribution of the tensor terms to the energy weighted sum rule is given analytically, and compared to the outcome of RPA. A microscopic origin of the quenching of GT sum rule due to the tensor force is discussed.(author)
Gamow-Teller resonances and a separable approximation for Skyrme tensor interactions
Directory of Open Access Journals (Sweden)
Severyukhin A. P.
2012-12-01
Full Text Available A finite rank separable approximation for the quasiparticle random phase approximation (QRPA with Skyrme interactions is applied to study properties of the Gamow-Teller (GT resonances in the neutron-rich Cd isotopes. This approximation enables one to reduce considerably the dimension of matrix that must be diagonalized to perform QRPA calculations in a very large configuration space. Our results from the SGII Skyrme interaction with the tensor interactions and the density-dependent zero-range pairing interaction show that the GT distribution is noticeably modified when the tensor correlations are taken into account. In particular, for 130Cd the dominant peak is moved 3.6 MeV downward and 10% of the GT distribution is shifted to the high excitation energy region near E=50MeV.
Role of momentum transfer in the quenching of the Gamow-Teller strength
International Nuclear Information System (INIS)
Marketin, T.; Martínez-Pinedo, G.; Paar, N.; Vretenar, D.
2012-01-01
A recent analysis of (p,n) and (n,p) reaction data from 90 Zr was performed recently, where a significant amount of Gamow-Teller strength was found above the resonance, an energy region previously unreachable by experimental setups. The extracted strengths in the β − and the β + channel indicate that approximately 10% of the total strength necessary to satisfy the model independent Ikeda sum rule is missing. One possible source of this discrepancy is the treatment of the isovector spin monopole (IVSM) mode of excitation which has been found to occurr at high excitation energies. Employing the relativistic Hartree-Bogoliubov (RHB) model and the protonneutron relativistic quasiparticle random phase approximation (pn-RQRPA) to calculate the nuclear response, we explore the contribution of the IVSM mode to the total L= 0 strength and apply our results to the available data.
Role of momentum transfer in the quenching of the Gamow-Teller strength
Energy Technology Data Exchange (ETDEWEB)
Marketin, T.; Martinez-Pinedo, G.; Paar, N.; Vretenar, D. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt, Germany and Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia)
2012-10-20
A recent analysis of (p,n) and (n,p) reaction data from {sup 90}Zr was performed recently, where a significant amount of Gamow-Teller strength was found above the resonance, an energy region previously unreachable by experimental setups. The extracted strengths in the {beta}{sub -} and the {beta}{sub +} channel indicate that approximately 10% of the total strength necessary to satisfy the model independent Ikeda sum rule is missing. One possible source of this discrepancy is the treatment of the isovector spin monopole (IVSM) mode of excitation which has been found to occurr at high excitation energies. Employing the relativistic Hartree-Bogoliubov (RHB) model and the protonneutron relativistic quasiparticle random phase approximation (pn-RQRPA) to calculate the nuclear response, we explore the contribution of the IVSM mode to the total L= 0 strength and apply our results to the available data.
International Nuclear Information System (INIS)
Poirier, E.
2002-12-01
Nuclei with A ∼ 70 along the N=Z line are known to be the scene of phenomena closely related to the nuclear deformation and are of particular interest since theoretical mean field calculations predict that a large part of the Gamow-Teller resonance might be located below the ground state of the mother nucleus and then be accessible through β-decay studies. These results have shown the effect of the shape of the ground state on the intensity of the Gamow-Teller strength. Thus, the experimental determination, through δ-decay, of the Gamow-Teller strength distribution and the comparison to the theoretical predictions allow to pin down the quadrupolar deformation parameter of the ground state of the parent nucleus. In order to study the neutron deficient isotopes of krypton (A=72,73,74,75) and strontium (A=76,77,78) and to establish the β-strength on the full energy range, a new total absorption spectrometer (TAgS) has been built in the frame of an international collaboration and installed at the (SOLDE/CERN mass separator. For the data analysis, the response function R of the spectrometer has been calculated by means of Monte-Carlo simulations, based on the GEANT4 code, and of a statistical description of the level scheme in the daughter nucleus. The β-feeding distribution has been obtained from experimental spectra through a method based on Bayes theorem and then converted into Gamow-Teller strength. The results coming from the 74 Kr decay analysis allow to describe the ground state of such a nucleus as the coexistence of an oblate shape and of a prolate shape. In the case of 76 Sr, the experimental Gamow-Teller strength distribution strongly indicates a prolate deformation. (author)
Lorentz-Lorenz quenching for the Gamow-Teller sum rule
International Nuclear Information System (INIS)
Delorme, J.; Ericson, M.; Figureau, A.
1984-03-01
We investigate the modification of the Gamow-Teller sum rule brought in by nucleonic excitations. The general trend of the data is well reproduced. The value of the force which mixes nucleonic and nuclear excitations is discussed
Gamow-Teller strength in deformed nuclei within self-consistent pnQRPA with the Gogny force
Directory of Open Access Journals (Sweden)
Martini M.
2014-03-01
Full Text Available In recent years fully consistent quasiparticle random-phase approximation (QRPA calculations using finite range Gogny force have been performed to study electromagnetic excitations of several axially-symmetric deformed nuclei up to the 238U. Here we present the extension of this approach to the charge-exchange nuclear excitations (pn-QRPA. In particular we focus on the Gamow-Teller (GT excitations. A comparison of the predicted GT strength distribution with existing experimental data is presented The role of nuclear deformation is shown. Special attention is paid to β-decay half-lives calculations for which experimental data exist.
International Nuclear Information System (INIS)
Batist, L.; Bykov, A.; Moroz, F.; Wittmann, V.; Alkhazov, G.D.; Keller, H.; Kirchner, R.; Klepper, O.; Roeckl, E.; Huyse, M.; Duppen, P. van; Reusen, G.; Plochocki, A.; Pfuetzner, M.; Rykaczewski, K.; Szerypo, J.; Zylicz, J.; Brown, B.A.
1994-10-01
The EC/β + -decay of the odd-odd nucleus 100 Ag was studied by means of total absorption γ-ray spectrometry. Most of the Gamow-Teller strength was found to be concentrated at an excitation energy of 5.6 MeV in 100 Pd, the FWHM of this resonance being 1.5 MeV. The measured strength distribution which is interpreted within the BCS approximation as being due to the dominant population of four-quasiparticle excitations, resembles the distribution predicted by an advanced shell-model calculation for the 98 Ag→ 98 Cd decay. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Poirier, E
2002-12-01
Nuclei with A {approx} 70 along the N=Z line are known to be the scene of phenomena closely related to the nuclear deformation and are of particular interest since theoretical mean field calculations predict that a large part of the Gamow-Teller resonance might be located below the ground state of the mother nucleus and then be accessible through {beta}-decay studies. These results have shown the effect of the shape of the ground state on the intensity of the Gamow-Teller strength. Thus, the experimental determination, through {delta}-decay, of the Gamow-Teller strength distribution and the comparison to the theoretical predictions allow to pin down the quadrupolar deformation parameter of the ground state of the parent nucleus. In order to study the neutron deficient isotopes of krypton (A=72,73,74,75) and strontium (A=76,77,78) and to establish the {beta}-strength on the full energy range, a new total absorption spectrometer (TAgS) has been built in the frame of an international collaboration and installed at the (SOLDE/CERN mass separator. For the data analysis, the response function R of the spectrometer has been calculated by means of Monte-Carlo simulations, based on the GEANT4 code, and of a statistical description of the level scheme in the daughter nucleus. The {beta}-feeding distribution has been obtained from experimental spectra through a method based on Bayes theorem and then converted into Gamow-Teller strength. The results coming from the {sup 74}Kr decay analysis allow to describe the ground state of such a nucleus as the coexistence of an oblate shape and of a prolate shape. In the case of {sup 76}Sr, the experimental Gamow-Teller strength distribution strongly indicates a prolate deformation. (author)
Gamow-Teller strength functions from N-nucleus scattering experiments at 200-400 MeV
International Nuclear Information System (INIS)
Haeusser, O.; British Columbia Univ., Vancouver; Vetterli, M.C.
1988-01-01
Recent measurements of (n,p), (p vector, p vector') and (p,n) reactions at TRIUMF have made possible a detailed examination of the spin-isospin structure of nuclear excitations up to 50 MeV. Cross sections for 54 Fe(n,p) 54 Mn and spin-flip cross sections for 54 Fe (p vector, p vector') near 300 MeV have been used to estimate the nuclear response for different multipoles L, spin transfers (ΔS = 0,1), and isospins of the residual nucleus (T f = 1,2). Qualitative features of the spin-flip probabilities in (p vector, p vector') are in good agreement with recent surface-RPA calculations. Between 200 and 400 MeV the ΔL=0 spin-flip isovector component is well described by the central part V στ of the Franey-Love interaction. The Gamow-Teller strength S + in 54 Fe, which is of significance in models of pre-collapse supernovae, is found to be smaller by a factor of two than the best available shell model calculations. In (sd)-shell nuclei ( 24,26 Mg, 28 Si) about (70±15)% of the Gamow-Teller strength predicted by untruncated shell-model calculations is found at low excitation. (orig.)
Nabi, Jameel-Un; Ishfaq, Mavra; Böyükata, Mahmut; Riaz, Muhammad
2017-10-01
At finite temperatures (≥ 107K), 76Se is abundant in the core of massive stars and electron capture on 76Se has a consequential role to play in the dynamics of core-collapse. The present work may be classified into two main categories. In the first phase we study the nuclear structure properties of 76Se using the interacting boson model-1 (IBM-1). The IBM-1 investigations include the energy levels, B (E 2) values and the prediction of the geometry. We performed the extended consistent-Q formalism (ECQF) calculation and later the triaxial formalism calculation (constructed by adding the cubic term to the ECQF). The geometry of 76Se can be envisioned within the formalism of the potential energy surface based on the classical limit of IBM-1 model. In the second phase, we reconfirm the unblocking of the Gamow-Teller (GT) strength in 76Se (a test case for nuclei having N > 40 and Z fashion. Results are compared with experimental data and previous calculations. The calculated GT distribution fulfills the Ikeda sum rule. Rates for β-delayed neutrons and emission probabilities are also calculated. Our study suggests that at high stellar temperatures and low densities, the β+-decay on 76Se should not be neglected and needs to be taken into consideration along with electron capture rates for simulation of presupernova evolution of massive stars.
Beta decay of 97Ag: evidence for the Gamow-Teller resonance near 100Sn
International Nuclear Information System (INIS)
Hu Zhiqiang
1999-03-01
In two complementary measurements, a cube like array of 6 Euroball-Cluster germanium detectors and a total-absorption γ-spectrometer were used to investigate the β decay of 97 Ag, a three proton-hole nucleus with respect to the 100 Sn core. The half-life and Q EC value of the decay of the 9/2 + ground-state of 97 Ag were determined to be 25.9(4) s and 6.98(11) MeV respectively. A total of 603 γ rays (578 new) was observed, and 151 levels (132 new) in 97 Pd have been identified. An interesting β-delayed γ cascade was observed, which comprises 6 γ-transitions with a de-excitation pattern involving an initial increase of the level spin. The Gamow-Teller (GT) β-decay strength distributions from the two measurements reveal a large GT resonance around 4 MeV with a width of about 1.8 MeV. The hindrance factor for the total GT strength summed from the ground-state up to 6 MeV excitation energy in 97 Pd, amounts to 4.3(6) with reference to a shell-model prediction. This factor is discussed in comparison with a core-polarization and a Monte-Carlo shell-model calculation. (orig.)
Double Gamow-Teller Transitions and its Relation to Neutrinoless β β Decay
Shimizu, Noritaka; Menéndez, Javier; Yako, Kentaro
2018-04-01
We study the double Gamow-Teller (DGT) strength distribution of 48Ca with state-of-the-art large-scale nuclear shell model calculations. Our analysis shows that the centroid energy of the DGT giant resonance depends mostly on the isovector pairing interaction, while the resonance width is more sensitive to isoscalar pairing. Pairing correlations are also key in neutrinoless β β (0 ν β β ) decay. We find a simple relation between the centroid energy of the 48Ca DGT giant resonance and the 0 ν β β decay nuclear matrix element. More generally, we observe a very good linear correlation between the DGT transition to the ground state of the final nucleus and the 0 ν β β decay matrix element. The correlation, which originates on the dominant short-range character of both transitions, extends to heavier systems including several β β emitters and also holds in energy-density functional results. Our findings suggest that DGT experiments can be a very valuable tool to obtain information on the value of 0 ν β β decay nuclear matrix elements.
Breaking of the SU(4) limit for the Gamow-Teller strength in N{proportional_to}Z nuclei
Energy Technology Data Exchange (ETDEWEB)
Petermann, I. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Gesellschaft fuer Schwerionenforschung Darmstadt, Darmstadt (Germany); Martinez-Pinedo, G. [Gesellschaft fuer Schwerionenforschung Darmstadt, Darmstadt (Germany); Langanke, K. [Gesellschaft fuer Schwerionenforschung Darmstadt, Darmstadt (Germany); Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); Caurier, E. [Universite Louis Pasteur, Institut de Recherches Subatomiques, Strasbourg (France)
2007-12-15
We have performed large-scale shell model calculations of the Gamow-Teller strength distributions in N{proportional_to}Z pf-shell nuclei. These calculations were motivated by the experimental attempts to measure the low-lying GT strength for the even-even N=Z+2 or N=Z-2 nuclei {sup 46}Ti, {sup 50}Cr, {sup 54}Fe and {sup 62}Ge, where a sizable low-energy GT strength could be interpreted as reminiscence of SU(4) symmetry; in the limit of exact SU(4) symmetry the GT{sub -} strength would be concentrated in a single transition to the lowest T=0, J=1{sup +} state in the daughter. We confirm that the SU(4) symmetry is strongly broken by the spin-orbit interaction and by increasing neutron excess. (orig.)
Observation of Fermi and Gamow-Teller strength in the 800 MeV(p,n) reaction
Energy Technology Data Exchange (ETDEWEB)
King, N S.P.; Lisowski, P W; Morgan, G L; Craig, P N; Jeppesen, R G; Lind, D A; Shepard, J R; Ullmann, J L; Zafiratos, C D; Goodman, C D
1986-08-07
Angular distributions have been measured for the (p,n) reaction on targets of /sup 6/Li, /sup 12/C, /sup 13/C, and /sup 15/N at 800 MeV with an energy resolution of 2.7 MeV allowing observation of discrete nuclear levels. As is the case at lower energies, this reaction is very selective, emphasizing Gamow-Teller (GT) and Fermi transitions. Absolute cross sections of pure GT transitions are reproduced by impulse approximation calculations. The ratio vertical strokeJsub(sigmatau)vertical stroke/sup 2//vertical strokeJsub(tau)vertical stroke/sup 2/ was extracted from /sup 13/C and /sup 15/N measurements at 800 MeV and from a /sup 13/C measurement at 318 MeV.
Gamow-Teller strength and lepton captures rates on 66-71Ni in stellar matter
Nabi, Jameel-Un; Majid, Muhammad
Charge-changing transitions play a significant role in stellar weak-decay processes. The fate of the massive stars is decided by these weak-decay rates including lepton (positron and electron) captures rates, which play a consequential role in the dynamics of core collapse. As per previous simulation results, weak interaction rates on nickel (Ni) isotopes have significant influence on the stellar core vis-à-vis controlling the lepton content of stellar matter throughout the silicon shell burning phases of high mass stars up to the presupernova stages. In this paper, we perform a microscopic calculation of Gamow-Teller (GT) charge-changing transitions, in the β-decay and electron capture (EC) directions, for neutron-rich Ni isotopes (66-71Ni). We further compute the associated weak-decay rates for these selected Ni isotopes in stellar environment. The computations are accomplished by employing the deformed proton-neutron quasiparticle random phase approximation (pn-QRPA) model. A recent study showed that the deformed pn-QRPA theory is well suited for the estimation of GT transitions. The astral weak-decay rates are determined over densities in the range of 10-1011g/cm3 and temperatures in the range of 0.01 × 109-30 × 109K. The calculated lepton capture rates are compared with the previous calculation of Pruet and Fuller (PF). The overall comparison demonstrates that, at low stellar densities and high temperatures, our EC rates are bigger by as much as two orders of magnitude. Our results show that, at higher temperatures, the lepton capture rates are the dominant mode for the stellar weak rates and the corresponding lepton emission rates may be neglected.
Quenching of the Gamow-Teller matrix element in closed LS-shell-plus-one nuclei
International Nuclear Information System (INIS)
Towner, I.S.
1989-06-01
It is evident that nuclear Gamow-Teller matrix elements determined from β-decay and charge-exchange reactions are significantly quenched compared to simple shell-model estimates based on one-body operators and free-nucleon coupling constants. Here we discuss the theoretical origins of this quenching giving examples from light nuclei near LS-closed shells, such as 16 0 and 40 Ca. (Author) 12 refs., 2 tabs
QRPA estimate for the Δ(1232) cotribution to the Gamow-Teller decay of heavy nuclei
International Nuclear Information System (INIS)
Suhonen, J.
1991-01-01
The contribution of the Δ(1232) isobars to the nuclear beta decay strength function is estimated in the framework of the charge-changing form of the QRPA. This procedure is applied to neutron-deficient tin isotopes. The results imply that the quenching of the low-energy Gamow-Teller decay strength cannot attributed to the presence of delta admixtures in the nuclear wave function. (orig.)
International Nuclear Information System (INIS)
Brown, B.A.; Wildenthal, B.H.
1983-01-01
The magnetic dipole moments of states in mirror pairs of the sd-shell nuclei and the strengths of the Gamow-Teller beta decays which connect them are compared with predictions based on mixed-configuration shell-model wave functions. From this analysis we extract the average effective values of the single-particle matrix elements of the l, s, and [Y/sup( 2 )xs]/sup( 1 ) components of the M1 and Gamow-Teller operators acting on nucleons in the 0d/sub 5/2/, 1s/sub 1/2/, and 0d/sub 3/2/ orbits. These results are compared with the recent calculations by Towner and Khanna of the corrections to the free-nucleon values of these matrix elements which arise from the effects of isobar currents, mesonic-exchange currents, and mixing with configurations outside the sd shell
Study of the giant Gamow-Teller resonance in nuclear beta-decay
International Nuclear Information System (INIS)
Dicklage, R.D. von; Hansen, P.G.
1984-01-01
A strong effort has been devoted to the development of new target-ion-source systems at ISOLDE which would give higher yields of proton-rich nuclei. The first break-trough has been obtained for the element argon where one recently was able to produce about three orders of magnitude higher yields than in the first experiments. This makes it possible to perform experiments, involving β-delayed protons and gamma-rays, which may give information about the giant Gamow-Teller resonance. This paper gives a report on the status of these experiments
A study of Gamow-Teller strength in A=37 nuclei
International Nuclear Information System (INIS)
Aufderheide, M.B.; Bloom, S.D.; Resler, D.A.; Goodman, C.D.
1992-01-01
An analysis is made of the recent β+ decay measurements of Garcia et al., in order to see whether the 1981 37 Cl(p,n) 37 Ar measurements of Rapaport et al. are consistent with them. Garcia et al., were not able to determine the amount of Gamow-Teller strength in the isobaric analog state (IAS) or the Coulomb mixing of Fermi strength to a state near the IAS, and were forced to determine the amount of Gamow-Teller strength in the daughter 1371 keV state by making the branching ratios sum to unity. These uncertainties leave a range of possible values open which we investigate. We find that the experiments are consistent within part of this range. We also examine the effect of this range of allowed values on solar and supernova neutrino cross sections of 37 Cl and find weak dependence on the uncertainties described here. We discuss how this range can be narrowed so that the consistency of the two experiments can be conclusively tested
Gamow-Teller transitions and proton-neutron pair correlation in N =Z odd-odd p -shell nuclei
Morita, Hiroyuki; Kanada-En'yo, Yoshiko
2017-10-01
We have studied the Gamow-Teller (GT) transitions from N =Z +2 neighbors to N =Z odd-odd nuclei in the p -shell region by using isospin-projected and β γ -constraint antisymmetrized molecular dynamics combined with the generator coordinate method. The calculated GT transition strengths from 0+1 states to 1+0 states such as 6He(01+1 ) →6Li(11+0 ) , 10Be(01+1 ) →10B(11+0 ) , and 14C(01+1 ) →14N(12+0 ) exhaust more than 50% of the sum rule. These N =Z +2 initial states and N =Z odd-odd final states are found to dominantly have S =0 ,T =1 n n pairs and S =1 ,T =0 p n pairs, respectively. Based on the two-nucleon (N N ) pair picture, we can understand the concentration of the GT strengths as the spin-isospin-flip transition n n (S =0 ,T =1 )→p n (S =1 ,T =0 ) in L S coupling. The GT transition can be a good probe to identify the spin-isospin partner states with n n pairs and p n pairs of N =Z +2 and N =Z odd-odd nuclei, respectively.
Beta decay of {sup 97}Ag: evidence for the Gamow-Teller resonance near {sup 100}Sn
Energy Technology Data Exchange (ETDEWEB)
Hu Zhiqiang
1999-03-01
In two complementary measurements, a cube like array of 6 Euroball-Cluster germanium detectors and a total-absorption {gamma}-spectrometer were used to investigate the {beta} decay of {sup 97}Ag, a three proton-hole nucleus with respect to the {sup 100}Sn core. The half-life and Q{sub EC} value of the decay of the 9/2{sup +} ground-state of {sup 97}Ag were determined to be 25.9(4) s and 6.98(11) MeV respectively. A total of 603 {gamma} rays (578 new) was observed, and 151 levels (132 new) in {sup 97}Pd have been identified. An interesting {beta}-delayed {gamma} cascade was observed, which comprises 6 {gamma}-transitions with a de-excitation pattern involving an initial increase of the level spin. The Gamow-Teller (GT) {beta}-decay strength distributions from the two measurements reveal a large GT resonance around 4 MeV with a width of about 1.8 MeV. The hindrance factor for the total GT strength summed from the ground-state up to 6 MeV excitation energy in {sup 97}Pd, amounts to 4.3(6) with reference to a shell-model prediction. This factor is discussed in comparison with a core-polarization and a Monte-Carlo shell-model calculation. (orig.)
Isospin symmetry of Tz =±3/2→±1/2 Gamow-Teller transitions in A=41 nuclei
Fujita, Y.; Shimbara, Y.; Adachi, T.; Berg, G. P.; Brown, B. A.; Fujita, H.; Hatanaka, K.; Kamiya, J.; Nakanishi, K.; Sakemi, Y.; Sasaki, S.; Shimizu, Y.; Tameshige, Y.; Uchida, M.; Wakasa, T.; Yosoi, M.
2004-11-01
Under the assumption that isospin T is a good quantum number, isobaric analog states and various analogous transitions are expected in isobars with mass number A . The strengths of Tz =±3/2→±1/2 analogous Gamow-Teller (GT) transitions and analogous M1 transitions within the A=41 isobar quartet are compared in detail. The Tz =+3/2→+1/2 GT transitions from the Jπ = 3/2+ ground state of 41K leading to excited Jπ = 1/2+ , 3/2+ , and 5/2+ states in 41Ca were measured using the ( 3He ,t) charge-exchange reaction. With a high energy resolution of 35 keV , many fragmented states were observed, and the GT strength distribution was determined up to 10 MeV excitation energy ( Ex ) . The main part of the strength was concentrated in the Ex =4 6 MeV region. A shell-model calculation could reproduce the concentration, but not so well details of the strength distribution. The obtained distribution was further compared with two results of 41Ti β decay studying the analogous Tz =-3/2→-1/2 GT strengths. They reported contradicting distributions. One-to-one correspondences of analogous transitions and analog states were assigned up to Ex =6 MeV in the comparison with one of these 41Ti β -decay results. Combining the spectroscopic information of the analog states in 41Ca and 41Sc , the most probable Jπ values were deduced for each pair of analog states. It was found that 5/2+ states carry the main part of the observed GT strength, while much less GT strength was carried by 1/2+ and 3/2+ states. The gross features of the GT strength distributions for each J were similar for the isospin analogous Tz =±3/2→±1/2 transitions, but the details were somewhat different. From the difference of the distributions, isospin-asymmetry matrix elements of ≈8 keV were deduced. The Coulomb displacement energy, which is sensitive to the configuration of states, showed a sudden increase of about 50 keV at the excitation energy of 3.8 MeV . The strengths of several M1 transitions to the
Isospin symmetry of T-z=+/- 3/2 ->+/- 1/2 Gamow-Teller transitions in A=41 nuclei
Fujita, Y; Shimbara, Y; Adachi, T; Berg, GPA; Fujita, H; Hatanaka, K; Kamiya, J; Nakanishi, K; Sakemi, Y; Sasaki, S; Shimizu, Y; Tameshige, Y; Uchida, M; Wakasa, T; Yosoi, M
2004-01-01
Under the assumption that isospin T is a good quantum number, isobaric analog states and various analogous transitions are expected in isobars with mass number A. The, strengths of T-z = +/-3/2 --> 1/2 analogous Gamow-Teller (GT) transitions and analogous M1 transitions within the A = 41 isobar
Isospin symmetry of T-z=+/- 3/2 ->+/- 1/2 Gamow-Teller transitions in A=41 nuclei
Fujita, Y; Shimbara, Y; Adachi, T; Berg, GPA; Fujita, H; Hatanaka, K; Kamiya, J; Nakanishi, K; Sakemi, Y; Sasaki, S; Shimizu, Y; Tameshige, Y; Uchida, M; Wakasa, T; Yosoi, M
Under the assumption that isospin T is a good quantum number, isobaric analog states and various analogous transitions are expected in isobars with mass number A. The, strengths of T-z = +/-3/2 --> 1/2 analogous Gamow-Teller (GT) transitions and analogous M1 transitions within the A = 41 isobar
Measurement of Gamow-Teller and spin dipole strength in the 45Sc(n,p)45Ca reaction at 198 MeV
International Nuclear Information System (INIS)
Alford, W.P.; Celler, A.; Brown, B.A.; Long, S.; Raywood, K.
1990-11-01
The reaction 45 Sc(n,p) 45 Ca has been studied at an energy of 198 MeV with energy resolution of about 1 MeV. Measurements were carried out at nominal angles 0, 3, 6, 9, 12, 15, and 18 degrees and spectra obtained up to ∼40 MeV excitation energy in 45 Ca. Significant Gamow-Teller strength is observed at an excitation energy of about 7 MeV, somewhat higher than predicted by shell model calculations. The strength observed is in agreement with calculations using g A /g V ≅ 1. The spin dipole giant resonance is seen with centroid at about 15 MeV excitation and total cross section of 25 mb/sr at an angle of 6 degrees. (Author) (22 refs., 9 figs.)
High-resolution study of Gamow-Teller transitions in the 47Ti(3He,t)47V reaction
Ganioǧlu, E.; Fujita, H.; Fujita, Y.; Adachi, T.; Algora, A.; Csatlós, M.; Deaven, J. M.; Estevez-Aguado, E.; Guess, C. J.; Gulyás, J.; Hatanaka, K.; Hirota, K.; Honma, M.; Ishikawa, D.; Krasznahorkay, A.; Matsubara, H.; Meharchand, R.; Molina, F.; Okamura, H.; Ong, H. J.; Otsuka, T.; Perdikakis, G.; Rubio, B.; Scholl, C.; Shimbara, Y.; Susoy, G.; Suzuki, T.; Tamii, A.; Thies, J. H.; Zegers, R. G. T.; Zenihiro, J.
2013-01-01
Given the importance of Gamow-Teller (GT) transitions in nuclear structure and astrophysical nuclear processes, we have studied Tz=+3/2→+1/2, GT transitions starting from the 47Ti nucleus in the (3He,t) charge-exchange reaction at 0∘ and at an intermediate incident energy of 140 MeV/nucleon. The experiments were carried out at the Research Center for Nuclear Physics (RCNP), Osaka, using the high-resolution facility with a high-dispersion beam line and the Grand-Raiden spectrometer. With an energy resolution of 20 keV, individual GT transitions were observed and GT strength was derived for each state populated up to an excitation energy (Ex) of 12.5 MeV. The GT strength was widely distributed from low excitation energy up to 12.5 MeV, where we had to stop the analysis because of the high level density. The distribution of the GT strengths was compared with the results of shell model calculations using the GXPF1 interaction. The calculations could reproduce the experimental GT distributions well. The GT transitions from the ground state of 47Ti and the M1 transitions from the isobaric analog state in 47V to the same low-lying states in 47V are analogous. It was found that the ratios of GT transition strengths to the ground state, the 0.088-MeV state, and the 0.146-MeV state are similar to the ratios of the strengths of the analogous M1 transitions from the isobaric analog state (IAS) to these states. The measured distribution of the GT strengths was also compared with those starting from the Tz=+3/2 nucleus 41K to the Tz=+1/2 nucleus 41Ca.
Gamow-Teller transitions and neutron-proton-pair transfer reactions
Van Isacker, P.; Macchiavelli, A. O.
2018-05-01
We propose a schematic model of nucleons moving in spin-orbit partner levels, j = l ± 1/2, to explain Gamow-Teller and two-nucleon transfer data in N = Z nuclei above 40Ca. Use of the LS coupling scheme provides a more transparent approach to interpret the structure and reaction data. We apply the model to the analysis of charge-exchange, 42Ca(3He,t)42Sc, and np-transfer, 40Ca(3He,p)42Sc, reactions data to define the elementary modes of excitation in terms of both isovector and isoscalar pairs, whose properties can be determined by adjusting the parameters of the model (spin-orbit splitting, isovector pairing strength and quadrupole matrix element) to the available data. The overall agreement with experiment suggests that the approach captures the main physics ingredients and provides the basis for a boson approximation that can be extended to heavier nuclei. Our analysis also reveals that the SU(4)-symmetry limit is not realized in 42Sc.
Ha, Eunja; Cheoun, Myung-Ki
2015-02-01
The deformed proton-neutron quasiparticle random phase approximation (QRPA) has been developed and applied to evaluate Gamow-Teller (GT) transition strength distributions, including high-lying excited states. The data of high-lying excited states are recently available beyond one or two nucleon threshold by charge exchange reactions using hundreds of MeV projectiles. Our calculations started with single-particle states calculated using a deformed, axially symmetric Woods-Saxon potential. The neutron-neutron and proton-proton pairing correlations are explicitly taken into account at the deformed Bardeen-Cooper-Schriffer theory. Additionally, the ground state correlations and two-particle and two-hole mixing states were included in the deformed QRPA. In this work, we used a realistic two-body interaction, given by the Brueckner G-matrix based on the CD Bonn potential to reduce the ambiguity on the nucleon-nucleon interactions inside nuclei. We applied our formalism to the GT transition strengths for 76Ge, 76,82Se, and 90,92Zr, and compared the results with the available experimental data. The GT strength distributions were sensitive to the deformation parameter as well as its sign, i.e., oblate or prolate. The Ikeda sum rule, which is usually thought to be satisfied under the one-body current approximation, regardless of nucleon models, was used to test our numerical calculations and shown to be satisfied without introducing the quenching factor, if high-lying GT excited states were properly taken into account. Most of the GT strength distributions of the nuclei considered in this work have the high-lying GT excited states beyond one-nucleon threshold, which are shown to be consistent with the available experimental data.
Ratio of Gamow-Teller to Fermi strength observed in /sup 13,14/C(p,n) at 492 and 590 MeV
International Nuclear Information System (INIS)
Ullmann, J.L.; Rapaport, J.; Lisowski, P.W.
1988-01-01
It has been recognized for a number of years that certain spin-isospin components of the nucleon-nucleus effective interaction can be inferred from (p,n) reactions to states of known nuclear structure. For L = 0, S = 0 and L = 0, S = 1 transitions, the 0-degree (p,n) cross section can be related respectively to Fermi and Gamow-Teller beta decay matrix elements. If these transitions occur in the same nucleus, the ratio of isovector spin-flip to non-spin-flip effective interactions can be measured without regard for absolute normalization. The best reaction to measure this is /sup 14/C(p,n) which goes by a pure Gamow-Teller transition to the 1/sup /plus// state at 3.95 MeV in /sup 14/N, and Fermi transition to the 2.31 MeV 0/sup /plus// state. This work extends the ratio measurements made at lower energies (ref. 1, 2, 3) to 492 and 590 MeV. We also report on the /sup 13/C(p,n) reaction which goes by a pure GT transition to the 3.51 MeV 3/2/sup /minus// state in /sup 13/N, but by a mixed Fermi plus Gamow-Teller transition to the 1/2/sup /minus// ground state. 11 refs., 4 figs., 2 tabs
Konieczka, M.; Kortelainen, M.; Satuła, W.
2018-03-01
Background: The atomic nucleus is a unique laboratory in which to study fundamental aspects of the electroweak interaction. This includes a question concerning in medium renormalization of the axial-vector current, which still lacks satisfactory explanation. Study of spin-isospin or Gamow-Teller (GT) response may provide valuable information on both the quenching of the axial-vector coupling constant as well as on nuclear structure and nuclear astrophysics. Purpose: We have performed a seminal calculation of the GT response by using the no-core configuration-interaction approach rooted in multireference density functional theory (DFT-NCCI). The model treats properly isospin and rotational symmetries and can be applied to calculate both the nuclear spectra and transition rates in atomic nuclei, irrespectively of their mass and particle-number parity. Methods: The DFT-NCCI calculation proceeds as follows: First, one builds a configuration space by computing relevant, for a given physical problem, (multi)particle-(multi)hole Slater determinants. Next, one applies the isospin and angular-momentum projections and performs the isospin and K mixing in order to construct a model space composed of linearly dependent states of good angular momentum. Eventually, one mixes the projected states by solving the Hill-Wheeler-Griffin equation. Results: The method is applied to compute the GT strength distribution in selected N ≈Z nuclei including the p -shell 8Li and 8Be nuclei and the s d -shell well-deformed nucleus 24Mg. In order to demonstrate a flexibility of the approach we present also a calculation of the superallowed GT β decay in doubly-magic spherical 100Sn and the low-spin spectrum in 100In. Conclusions: It is demonstrated that the DFT-NCCI model is capable of capturing the GT response satisfactorily well by using a relatively small configuration space, exhausting simultaneously the GT sum rule. The model, due to its flexibility and broad range of applicability, may
International Nuclear Information System (INIS)
Scholl, Clemens
2010-01-01
Excited states in the light nuclei 9 B and 13 C were studied using the ( 3 He,t) charge-exchange reaction on 9 Be and 13 C targets. The measurements were performed at the research center for nuclear physics (RCNP) in Osaka, Japan, using the magnetic spectrometer Grand Raiden and the dispersive WS course. The 3 He beam with an energy of 420 MeV was accelerated by the RCNP Ring Cyclotron. The Grand Raiden spectrometer and the WS course allow to study the ( 3 He,t) charge-exchange reaction with an energy resolution of around 30 keV, which is one order of magnitude better than measurements with the (p,n) charge-exchange reaction. The high resolution allows to better separate individual states and to determine weak excitation strengths because of low background in the spectra. A total of 19 states in 13 N were studied, and a total of 20 states were observed in 9 B. Of these, 9 states in 13 C and 10 states in 9 B were identified as being excited by a Gamow-Teller transition. Charge-exchange reactions are related to beta-decay, and at zero momentum transfer a simple proportionality exists between the cross-section of the charge-exchange experiment and the Fermi (F) or Gamow-Teller (GT) beta-decay strength. While the Fermi strength B(F) is concentrated in the transition to the isobaric analog state, the Gamow-Teller strength B(GT) is scattered among the excited states. The main aim of the present study is to determine the B(GT) strengths in the nuclei 9 B and 13 N. The only charge-exchange study of 9 B was made 30 years ago with the (p,n) reaction and a resolution of around 300-400 keV. Many states, especially at high excitation energy, could not be resolved by that study. The present work was able to separate many weakly excited states with small decay width at high excitation energies (12-19 MeV) in 9 B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The results point to a strong difference in spatial structure between the
Energy Technology Data Exchange (ETDEWEB)
Scholl, Clemens
2010-07-07
Excited states in the light nuclei {sup 9}B and {sup 13}C were studied using the ({sup 3}He,t) charge-exchange reaction on {sup 9}Be and {sup 13}C targets. The measurements were performed at the research center for nuclear physics (RCNP) in Osaka, Japan, using the magnetic spectrometer Grand Raiden and the dispersive WS course. The {sup 3}He beam with an energy of 420 MeV was accelerated by the RCNP Ring Cyclotron. The Grand Raiden spectrometer and the WS course allow to study the ({sup 3}He,t) charge-exchange reaction with an energy resolution of around 30 keV, which is one order of magnitude better than measurements with the (p,n) charge-exchange reaction. The high resolution allows to better separate individual states and to determine weak excitation strengths because of low background in the spectra. A total of 19 states in {sup 13}N were studied, and a total of 20 states were observed in {sup 9}B. Of these, 9 states in {sup 13}C and 10 states in {sup 9}B were identified as being excited by a Gamow-Teller transition. Charge-exchange reactions are related to beta-decay, and at zero momentum transfer a simple proportionality exists between the cross-section of the charge-exchange experiment and the Fermi (F) or Gamow-Teller (GT) beta-decay strength. While the Fermi strength B(F) is concentrated in the transition to the isobaric analog state, the Gamow-Teller strength B(GT) is scattered among the excited states. The main aim of the present study is to determine the B(GT) strengths in the nuclei {sup 9}B and {sup 13}N. The only charge-exchange study of {sup 9}B was made 30 years ago with the (p,n) reaction and a resolution of around 300-400 keV. Many states, especially at high excitation energy, could not be resolved by that study. The present work was able to separate many weakly excited states with small decay width at high excitation energies (12-19 MeV) in {sup 9}B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The
Energy Technology Data Exchange (ETDEWEB)
Ha, Eunja; Cheoun, Myung-Ki [Soongsil University, Origin of Matter and Evolution of Galaxy Institute and Department of Physics, Seoul (Korea, Republic of)
2017-02-15
We investigated Gamow-Teller (GT) transitions and strength distributions of s-d shell N = Z nuclei, {sup 24}Mg, {sup 28}Si, and {sup 32}S, by a deformed quasi-particle random phase approximation (DQRPA). In the DQRPA, we included particle model space up to p-f shell and considered explicitly the deformation as well as the like- and unlike-pairing correlations. Shell evolution by deformation and attractive force by unlike-pairing correlations turned out to play vital roles to reproduce the experimental GT data. Correlations between the deformation and the pairing correlations are also discussed with the comparison to the experimental data shape. (orig.)
Inelastic electron scattering, fine structure of M1 giant resonances and Gamow-Teller states
International Nuclear Information System (INIS)
Richter, A.
1983-01-01
Recent progress in obtaining detailed fine structure distributions of magnetic giant resonances in nuclei using high resolution inelastic electron scattering at low energy is discussed. Specific examples chosen are the medium heavy nuclei 40 42 44 48 Ca in which M1 excitations are due to neutron spin-flip transitions and the N=28 isotones 50 Ti, 52 Cr and 54 Fe where in addition also proton excitations contribute to the measured M1 strength. It is found that the M1 strength is very fragmented and considerably quenched in comparison to predictions of shell model calculations in a model space that includes up to 2p-2h excitations. Finally, the old problem of M1 strength in 208 Pb is revisited and the results of a form factor measurement of a recently discovered low lying Jsup(π)=1 + state by nuclear resonance fluorescence are presented. (Auth.)
Energy Technology Data Exchange (ETDEWEB)
Fujiwara, M.; Fujita, Y.; Katayama, I.; Morinobu, S.; Yamazaki, T.; Itahashi, T.; Ikegami, H. [Osaka Univ., Suita (Japan). Research Center for Nuclear Physics; Hayakawa, S. I.; Ikegami, Hidetsugu; Muraoka, Mitsuo [eds.; Osaka Univ., Suita (Japan). Research Center for Nuclear Physics
1980-01-01
A Gamow-Teller giant resonance in /sup 90/Nb was excited by the /sup 90/Zr(/sup 3/He, t) reaction at 89.5 MeV. The strength of the resonance was localized in the energy region of Ex = 4.5 - 7.5 MeV. The transition was found to be dominated by the L = 2 transfer.
International Nuclear Information System (INIS)
Mercer, D.J.
1993-01-01
Measurements of neutron polarization from (rvec p,rvec n) reactions can provide valuable clues toward understanding the isovector nucleon-nucleus interaction. A neutron time-of-flight polarimeter has been constructed at the Los Alamos Meson Physics Facility to perform such measurements, but before the polarimeter can be used, its effective analyzing powers must be determined. This is accomplished by using the 14 C(rvec p,rvec n) 14 N reaction at a bombarding energy of 494 MeV to produce a beam of neutrons with known polarization, illuminating the detector with these neutrons, and measuring the azimuthal asymmetries after scattering from a hydrogenous analyzer fluid within the detector. Secondary measurements are made using the 2 H(rvec p,rvec n) 2 p reaction with bombarding energies of 318 and 494 MeV to produce a polarized neutron beam. The results from (rvec np) analyzing reactions within the detector agree with values anticipated from free nucleon-nucleon analyzing powers, but the results from (rvec np) analyzing reactions display a more than 33% reduction from the anticipated values. Additionally, measurements are made of the polarization transfer coefficient D LL (0 degree) for rvec p,rvec n Gamow-Teller reactions on 2 H, 7 Li 12 C, and 14 C targets. For a purely central interaction, one would expect that D LL (0 degree) ∼ -1/3 in the plane wave limit, but a simple average of the Jπ = 0 + → 1 + results at a bombardment energy of 494 MeV gives D LL (0 degree) = -0.689 ± 0.044. Thus, the measurements indicate that the nucleon-nucleus interaction -- which is largely central at 200 MeV -- has strong tensor contributions at higher energy
Does the delta quench Gamow-Teller strength in (p,n)- and (p vector,p vector')-reactions
International Nuclear Information System (INIS)
Osterfeld, F.; Schulte, A.; Udagawa, T.; Yabe, M.
1986-01-01
Microscopic analyses of complete forward angle intermediate energy (p,n)-, ( 3 He,t)- and (p vector,p vector')-spin-flip spectra are presented for the reactions 90 Zr(p,n), 90 Zr( 3 He,t) and 90 Zr(p vector,p vector'). It is shown that the whole spectra up to high excitation energies (E X ∝50 MeV) are the result of correlated one-particle-one-hole (1p1h) spin-isospin transitions only. The spectra reflect, therefore, the linear spin-isospin response of the target nucleus to the probing external hadronic fields. Our results suggest that the measured (p,n)-, ( 3 He,t)- and (p vector,p vector')-cross sections are compatible with the transition strength predictions as obtained from random phase approximation (RPA) calculations. This means that the Δ isobar quenching mechanism is likely to be rather small. (orig.)
Cheoun, Myung-Ki; Ha, Eunja
2013-07-01
With the advent of high analysis technology in detecting the Gamow-Teller (GT) excited states beyond one nucleon emission threshold, the quenching of the GT strength to the Ikeda sum rule (ISR) seems to be recovered by the high-lying (HL) GT states. We address that these HL GT excited states result from the smearing of the Fermi surface by the increase of the chemical potential owing to the deformation within a framework of the deformed quasi-particle random phase approximation (DQRPA). Detailed mechanism leading to the smearing is discussed, and comparisons to the available experimental data on 76Ge,82Se and N = 20 nuclei are shown to explain the strong peaks on the HL GT excited states.
International Nuclear Information System (INIS)
Cheoun, Myung-Ki; Ha, Eunja
2013-01-01
With the advent of high analysis technology in detecting the Gamow-Teller (GT) excited states beyond one nucleon emission threshold, the quenching of the GT strength to the Ikeda sum rule (ISR) seems to be recovered by the high-lying (HL) GT states. We address that these HL GT excited states result from the smearing of the Fermi surface by the increase of the chemical potential owing to the deformation within a framework of the deformed quasi-particle random phase approximation (DQRPA). Detailed mechanism leading to the smearing is discussed, and comparisons to the available experimental data on 76 Ge, 82 Se and N = 20 nuclei are shown to explain the strong peaks on the HL GT excited states
Nuclear structure calculations in $^{20}$Ne with No-Core Configuration-Interaction model
Konieczka, Maciej; Satuła, Wojciech
2016-01-01
Negative parity states in $^{20}$Ne and Gamow-Teller strength distribution for the ground-state beta-decay of $^{20}$Na are calculated for the very first time using recently developed No-Core Configuration-Interaction model. The approach is based on multi-reference density functional theory involving isospin and angular-momentum projections. Advantages and shortcomings of the method are briefly discussed.
A statistical calculation of the β- strength function
International Nuclear Information System (INIS)
Arvieu, R.; Haq, R.U.; Touchard, J.
1976-01-01
A microscopic calculation of the Gamow-Teller strength between the 0 + ground state of 208 Pb and the 1 + particle-hole states of 208 Bi assuming the particle-hole matrix elements as random numbers with some specified distribution, is described. Under certain conditions for the two-body matrix elements, a G.T. resonance occurs. The stability of this collective state along with the accompanying low energy β - -strength tail is studied for various samples of p-h matrix elements [fr
Statistical theory for calculating energy spectra of β-delayed neutrons
International Nuclear Information System (INIS)
Kawano, Toshihiko; Moeller, Peter; Wilson, William B.
2008-01-01
Theoretical β-delayed neutron spectra are calculated based on the Quasi-particle Random Phase Approximation (QRPA) and the Hauser-Feshbach statistical model. Neutron emissions from an excited daughter nucleus after β-decay to the granddaughter residual are more accurately calculated than previous evaluations, including all the microscopic nuclear structure information, such as a Gamow-Teller strength distribution and discrete states in the granddaughter. The calculated delayed-neutron spectra reasonably agree with those evaluations in the ENDF decay library, which are based on experimental data. The model was adopted to generate the delayed-neutron spectra for all 271 precursors. (authors)
Shell-model calculations of beta-decay rates for s- and r-process nucleosyntheses
International Nuclear Information System (INIS)
Takahashi, K.; Mathews, G.J.; Bloom, S.D.
1985-01-01
Examples of large-basis shell-model calculations of Gamow-Teller β-decay properties of specific interest in the astrophysical s- and r- processes are presented. Numerical results are given for: (1) the GT-matrix elements for the excited state decays of the unstable s-process nucleus 99 Tc; and (2) the GT-strength function for the neutron-rich nucleus 130 Cd, which lies on the r-process path. The results are discussed in conjunction with the astrophysics problems. 23 refs., 3 figs
International Nuclear Information System (INIS)
Grotz, K.; Klapdor, H.V.; Metzinger, J.
1986-01-01
Calculations of the neutrino capture cross sections for /sup 69,71/Ga based on a microscopic treatment of the Gamow-Teller matrix elements are presented. A strong enhancement of the cross section for highly energetic neutrinos is found compared to previous phenomenological estimates. As a consequence, the present assumptions on the signal from 8 B neutrinos in 71 Ga have to be revised. A non-negligible solar model dependent background of 8 B neutrinos has to be expected in a gallium solar neutrino experiment together with the pp signal. The calculations yield a larger sensitivity of the gallium detector than assumed previously for galactic neutrinos
The beta strength function structure in β+ decay of lutetium, thulium and cesium isotopes
International Nuclear Information System (INIS)
Alkhazov, G.D.; Bykov, A.A.; Vitman, V.D.; Naumov, Yu.V.; Orlov, S.Yu.
1981-01-01
The spectra of total γ-absorption in the decays of some Lutecium, Thulium and Cesium isotopes have been measured. The probabilities for level population in the decay of the isotopes have been determined. The deduced beta strength functions reveal pronounced structure. Calculations of the strength functions using the Saxon-Woods potential and the residual Gamow-Teller interaction are presented. It is shown that in β + decay of light Thulium and Cesium isotopes the strength function comprises more than 70% of the Gamow-Teller excitations with μsub(tau) = +1. This result is the first direct observation of the Gamow-Teller resonance in β + decay of nuclei with Tsub(z) > O. (orig.)
Gamow-Teller strength functions and neutrino problems
International Nuclear Information System (INIS)
Haxton, W.C.
1982-01-01
A quantitative understanding of spin strengths in nuclei is of vital importance in studies of nuclear double beta decay and in solar neutrino spectroscopy. The current status of these problems is outlined
Electronic structure of SnS deduced from photoelectron spectra and band-structure calculations
Ettema, A.R.H.F.; Groot, R.A. de; Haas, C.; Turner, T.S.
1992-01-01
SnS is a layer compound with a phase transition from a high-temperature β phase to a low-temperature α phase with a lower symmetry. Ab initio band-structure calculations are presented for both phases. The calculations show that the charge distributions in the two phases are very similar. However,
Allowed Gamow-Teller excitations from the ground state of N-14
Czech Academy of Sciences Publication Activity Database
Aroua, S.; Navrátil, Petr; Zamick, L.; Fayche, M. S.; Barret, B. R.; Vary, J. P.; Heyde, K.
2003-01-01
Roč. 720, 1/2 (2003), s. 71-83 ISSN 0375-9474 Institutional research plan: CEZ:AV0Z1048901 Keywords : core shell-model * tensor interactions * light-nuclei Subject RIV: BE - Theoretical Physics Impact factor: 1.761, year: 2003
Beta-delayed fission and neutron emission calculations for the actinide cosmochronometers
International Nuclear Information System (INIS)
Meyer, B.S.; Howard, W.M.; Mathews, G.J.; Takahashi, K.; Moeller, P.; Leander, G.A.
1989-01-01
The Gamow-Teller beta-strength distributions for 19 neutron-rich nuclei, including ten of interest for the production of the actinide cosmochronometers, are computed microscopically with a code that treats nuclear deformation explicitly. The strength distributions are then used to calculate the beta-delayed fission, neutron emission, and gamma deexcitation probabilities for these nuclei. Fission is treated both in the complete damping and WKB approximations for penetrabilities through the nuclear potential-energy surface. The resulting fission probabilities differ by factors of 2 to 3 or more from the results of previous calculations using microscopically computed beta-strength distributions around the region of greatest interest for production of the cosmochronometers. The indications are that a consistent treatment of nuclear deformation, fission barriers, and beta-strength functions is important in the calculation of delayed fission probabilities and the production of the actinide cosmochronometers. Since we show that the results are very sensitive to relatively small changes in model assumptions, large chronometric ages for the Galaxy based upon high beta-delayed fission probabilities derived from an inconsistent set of nuclear data calculations must be considered quite uncertain
Deformation of the N=Z nucleus $^{76}$Sr using $\\beta$-decay studies
Nacher, E; Rubio, B; Taín, J L; Cano-Ott, D; Courtin, S; Dessagne, P; Maréchal, F; Miehé, C; Poirier, E; García-Borge, M J; Escrig, D; Jungclaus, A; Sarriguren, P; Tengblad, O; Gelletly, W; Fraile-Prieto, L M; Le Scornet, G; Dessagne, Ph.; Miehe, Ch.
2004-01-01
A novel method of deducing the deformation of the N=Z nucleus $^{76}$Sr is presented. It is based on the comparison of the experimental Gamow-Teller strength distribution B(GT) from its $\\beta$-decay with the results of QRPA calculations. This method confirms previous indications of the strong prolate deformation of this nucleus in a totally independent and novel way. The measurement has been carried out with a large Total Absorption Gamma Spectrometer, "Lucrecia", newly installed at CERN-ISOLDE.
FANG, CM; ETTEMA, ARHF; HAAS, C; WIEGERS, GA; VANLEUKEN, H; DEGROOT, RA
1995-01-01
In order to understand the electronic structure of the misfit-layer compound (SnS)(1.17)NbS2 we carried out an ab initio band-structure calculation of the closely related commensurate compound (SnS)(1.20)NbS2. The band structure is compared with calculations for NbS2 and for hypothetical SnS with
Fang, C.M.; Ettema, A.R.H.F.; Haas, C.; Wiegers, G.A.; Leuken, H. van; Groot, R.A. de
1995-01-01
In order to understand the electronic structure of the misfit-layer compound (SnS)1.17NbS2 we carried out an ab initio band-structure calculation of the closely related commensurate compound (SnS)1.20NbS2. The band structure is compared with calculations for NbS2 and for hypothetical SnS with
International Nuclear Information System (INIS)
Moeller, Peter; Pfeiffer, Bernd; Kratz, Karl-Ludwig
2003-01-01
Recent compilations of experimental gross β-decay properties, i.e., half-lives (T 1/2 ) and neutron-emission probabilities (P n ), are compared to improved global macroscopic-microscopic model predictions. The model combines calculations within the quasiparticle (QP) random-phase approximation for the Gamow-Teller (GT) part with an empirical spreading of the QP strength and the gross theory for the first-forbidden part of β - decay. Nuclear masses are either taken from the 1995 data compilation of Audi et al., when available, otherwise from the finite-range droplet model. Especially for spherical and neutron-(sub-)magic isotopes a considerable improvement compared to our earlier predictions for pure GT decay (ADNDT, 1997) is observed. T 1/2 and P n values up to the neutron drip line have been used in r-process calculations within the classical 'waiting-point' approximation. With the new nuclear-physics input, a considerable speeding-up of the r-matter flow is observed, in particular at those r-abundance peaks which are related to magic neutron-shell closures
Beta-decay of {sup 103}In: evidence for the Gamow-Teller resonance near {sup 100}Sn
Energy Technology Data Exchange (ETDEWEB)
Karny, M. [Warsaw Univ. (Poland). Inst. of Experimental Physics; Batist, L.; Brown, B.A. [and others
1998-04-01
The {beta} decay of the neutron-deficient isotope {sup 103}In was investigated by using total absorption {gamma}-ray spectrometry on mass-separated sources. The measurement reveals a high-lying resonance of the {beta}-decay strength in striking disagreement with high-resolution {gamma}-ray data. The result is discussed in comparison with shell-model predictions. (orig.)
Sum rules for nuclear excitations with the Skyrme-Landau interaction
International Nuclear Information System (INIS)
Liu Kehfei; Luo Hongde; Ma Zhongyu; Feng Man; Shen Qingbiao
1991-01-01
The energy-weighted sum rules for electric, magnetic, Fermi and Gamow-Teller transitions with the Skyrme-Landau interaction are derived from the double commutators and numerically calculated in a HF + RPA formalism. As a numerical check of the Thouless theorem, our self-consistent calculations show that the calculated RPA strengths exhaust more than 85% of the sum rules in most cases. The well known non-energy-weighted sum rules for Fermi and Gamow-Teller transitions are also checked numerically. The sum rules are exhausted by more than 94% in these cases. (orig.)
Analysis of (3He, t) charge exchange reactions at 140 AMeV
International Nuclear Information System (INIS)
Singh, Pardeep; Zegers, R.G.T.; Danielewicz, Pawel; Noji, S.; Kim, B.T.; Sakai, H.
2014-01-01
The spin-isospin response in nuclei has been studied widely through ( 3 He, t) and (t, 3 He) charge-exchange reactions wherein a proton (neutron) transforms into a neutron (proton), which in turn changes the isospin, ΔT=1, of the nuclei participating in the reaction, either with or without spin transfer. The Gamow-Teller transitions are used to obtain the weak transition strength in the excitation-energy regions inaccessible through β-decay. The strengths deduced using charge exchange experiments provide stringent tests for nuclear structure calculations and serve as inputs for variety of applications in which weak transition strengths play a role. In this context, we explore here the ( 3 He,t) charge-exchange reaction at 140 MeV/u on 18 O, 26 Mg, 58,60,62, 64 Ni, 90 Zr, 118,120 Sn and 208 Pb targets, within the theoretical framework of distorted wave impulse approximation
Gamow-Teller matrix elements from the C-12(d,He-2) and Mg-24(d,He-2) reactions at 170 MeV
Baumer, C; Frekers, D; Schmidt, R; van den Berg, AM; Hannen, VM; Harakeh, MN; de Huu, MA; Wörtche, HJ; De Frenne, D; Hagemann, M; Heyse, J; Jacobs, E; Fujita, Y
The Mg-24(d,He-2)Na-24 and the C-12(d,He-2)B-12 charge-exchange reactions have been studied at an incident energy of 170 MeV. The two protons in the S-1(0)(pp) state (indicated as He-2) were both momentum analyzed and detected by the same spectrometer and detector. Background-free He-2 spectra with
International Nuclear Information System (INIS)
Saito, T.Y.; Wu, Y.; Ishikawa, S.; Sasakawa, T.
1990-01-01
Triton β-decay has been calculated using wave functions for 3 He and 3 H obtained from (Coulomb-modified) Faddeev equations for various interactions. We get a value for the Gamow-Teller matrix element of √3 (0.962±0.002) without regards to two- or three-nucleon inteactions. This value agrees with the experimental value. (orig.)
Low-energy Electro-weak Reactions
International Nuclear Information System (INIS)
Gazit, Doron
2012-01-01
Chiral effective field theory (EFT) provides a systematic and controlled approach to low-energy nuclear physics. Here, we use chiral EFT to calculate low-energy weak Gamow-Teller transitions. We put special emphasis on the role of two-body (2b) weak currents within the nucleus and discuss their applications in predicting physical observables.
International Nuclear Information System (INIS)
Rykaczewski, Krzysztof Piotr; Karny, M.; Batist, L.; Banu, A.; Becker, F.; Blazhev, A.; Burkard, K.; Bruchle, W.; Doring, J.; Faestermann, T.; Gorska, M.; Grawe, H.; Janas, Z.; Jungclaus, A.; Kavatsyuk, M.; Kavatsyuk, O.; Kirchner, R.; La Commara, M.; Mandal, S.; Mazzocchi, C.; Miernik, K.; Mukha, I.; Muralithar, S.; Plettner, C.; Plochocki, A.; Roeckl, E.; Romoli, M.; Schadel, M.; Schmidt, K.; Schwengner, R.; Zylicz, J.
2005-01-01
The β-decay of 102 Sn was studied by using high-resolution germanium detectors as well as a Total Absorption Spectrometer (TAS). A decay scheme has been constructed based on the γ-γ coincidence data. The total experimental Gamow-Teller strength B GT exp of 102 Sn was deduced from the TAS data to be 4.2(9). A search for β-delayed γ-rays of 100 Sn decay remained unsuccessful. However, a Gamow-Teller hindrance factor h = 2.2(3), and a cross-section of about 3nb for the production of 100 Sn in fusion-evaporation reaction between 58 Ni beam and 50 Cr target have been estimated from the data on heavier tin isotopes. The estimated hindrance factor is similar to the values derived for lower shell nuclei
Nuclear Structure Calculations for Two-Neutrino Double-β Decay
Directory of Open Access Journals (Sweden)
P. Sarriguren
2016-01-01
Full Text Available We study the two-neutrino double-β decay in 76Ge, 116Cd, 128Te, 130Te, and 150Nd, as well as the two Gamow-Teller branches that connect the double-β decay partners with the states in the intermediate nuclei. We use a theoretical microscopic approach based on a deformed self-consistent mean field with Skyrme interactions including pairing and spin-isospin residual forces, which are treated in a proton-neutron quasiparticle random-phase approximation. We compare our results for Gamow-Teller strength distributions with experimental information obtained from charge-exchange reactions. We also compare our results for the two-neutrino double-β decay nuclear matrix elements with those extracted from the measured half-lives. Both single-state and low-lying-state dominance hypotheses are analyzed theoretically and experimentally making use of recent data from charge-exchange reactions and β decay of the intermediate nuclei.
Nuclear properties for astrophysical applications
Energy Technology Data Exchange (ETDEWEB)
Moeller, P.; Nix, J.R. [Los Alamos National Lab., NM (United States); Kratz, K.L. [Mainz Univ. (Germany). Inst. fuer Kernchemie
1994-09-23
We tabulate the ground-state odd-proton and odd-neutron spins, proton and neutron pairing gaps, binding energies, neuton separation energies, quantities related to {beta}-delayed one, two and three neutron emission probabilities, {beta}-decay Q values and half-lives with respect to Gamow-Teller decay, proton separation energies, and {alpha}-decay Q values and half-lives. The starting point of the calculations is a calculation of nuclear ground-states and (information based on the finite-range droplet model and the folded-Yukawa single-particle model published in a previous issue of ATOMIC DATA AND NUCLEAR DATA TABLES. The {beta}-delayed neutron-emission probabilities and Gamow-Teller {beta}-decay rates are obtained from a QRPA model that uses single-particle levels and wave-functions at the calculated nuclear ground-state shape as the starting point.
Configuration interaction calculations for the region of 76Ge
Brown, Alex
2017-09-01
I will present a short history of the configuration interaction Hamiltonians that have been developed for the (0f5 / 2 , 1p3 / 2 , 1p1 / 2 , 0g9 / 2) (jj 44) model space. This model space is appropriate for the region of nuclei bounded by the nickel isotopes for Z = 28 and the isotones with N = 50 . I will discuss results for the double-beta decay of 76Ge that lies in the jj 44 region. I will show results for the structure of nuclei around 76Ge for some selected data from gamma decay, Gamow-Teller beta decay, charge-exchange reactions, one-nucleon transfer reactions, and two-nucleon transfer reactions. This work was supported by NSF Grant PHY-1404442.
Deducing magnetic resonance neuroimages based on knowledge from samples.
Jiang, Yuwei; Liu, Feng; Fan, Mingxia; Li, Xuzhou; Zhao, Zhiyong; Zeng, Zhaoling; Wang, Yi; Xu, Dongrong
2017-12-01
Because individual variance always exists, using the same set of predetermined parameters for magnetic resonance imaging (MRI) may not be exactly suitable for each participant. We propose a knowledge-based method that can repair MRI data of undesired contrast as if a new scan were acquired using imaging parameters that had been individually optimized. The method employed a strategy called analogical reasoning to deduce voxel-wise relaxation properties using morphological and biological similarity. The proposed framework involves steps of intensity normalization, tissue segmentation, relaxation time deducing, and image deducing. This approach has been preliminarily validated using conventional MRI data at 3T from several examples, including 5 normal and 9 clinical datasets. It can effectively improve the contrast of real MRI data by deducing imaging data using optimized imaging parameters based on deduced relaxation properties. The statistics of deduced images shows a high correlation with real data that were actually collected using the same set of imaging parameters. The proposed method of deducing MRI data using knowledge of relaxation times alternatively provides a way of repairing MRI data of less optimal contrast. The method is also capable of optimizing an MRI protocol for individual participants, thereby realizing personalized MR imaging. Copyright © 2017 Elsevier Ltd. All rights reserved.
Beta-delayed particle decay of 17Ne
International Nuclear Information System (INIS)
Morton, A.C.; Chow, J.C.; King, J.D.; Boyd, R.N.; Bateman, N.P.T.; Buchmann, L.; D'Auria, J.M.; Davinson, T.; Dombsky, M.; Galster, W.; Gete, E.; Giesen, U.; Iliadis, C.; Jackson, K.P.; Powell, J.; Roy, G.; Shotter, A.
2002-01-01
The β-delayed particle decay of 17 Ne has been studied via proton-γ coincidences, time-of-flight measurements and the ''ratio-cut technique'', allowing cleanly-separated proton and α-particle spectra to be obtained. A complete set of proton and α branching ratios for the decay of 14 excited states in 17 F to the ground and excited states of 16 O and 13 N has been determined and branching ratios for the β decay of 17 Ne to these states have been deduced. From the branching ratios, f A t values and reduced Gamow-Teller matrix elements were calculated; no indication of isospin mixing in the isobaric analog state in 17 F was observed. From the measurement of proton-γ angular correlations, combined with the selection rules for an allowed β decay, we obtain J π =((1)/(2)) - for states at 8.436 and 9.450 MeV and ((3)/(2)) - for the state at 10.030 MeV in 17 F. Probabilities for the β-delayed pα decay to 12 C through the tails of the subthreshold 7.117 and 6.917 MeV states in 16 O have been calculated and the feasibility of using such decays to provide information about the rates for the E1 and E2 components of the 12 C(α,γ) 16 O reaction is discussed
Energy Technology Data Exchange (ETDEWEB)
Achouri, N.L
2001-09-01
This thesis describes two studies which explore the structure of proton-rich nuclei. The first of these concerned an investigation of the {beta}-delayed charged particle decay of {sup 22}Al. The experiment was carried out using the LISE3 spectrometer at GANIL and permitted the energies of the {beta}-p, {beta}-2p and {beta}-{alpha} transitions together with the corresponding branching ratios to be determined with an improved precision over earlier work. In addition the coincidences with {gamma}-rays were measured for the first time allowing the decay scheme to be reconstructed. Comparison with shell model calculations using the code OXBASH and the mirror nucleus {sup 22}F allowed the spin and parity and the mass of {sup 22}Al g.s. as well as levels in {sup 22}Mg to be deduced. The experimentally determined Gamow Teller strength was found to be in good agreement at low excitation energies with a shell model calcination employing an effective operator. The second study concerned the development of resonant elastic scattering in inverse kinematics as a spectroscopic tool. Extensive simulations were carried out to ascertain the feasibility of such experiments as well as to optimise the set-up. In the context of the later, particular attention was paid to the final resolution. Experiments subsequently undertaken at GANIL with stable and radioactive beams demonstrated that the technique will be a powerful spectroscopic tool for use with radioactive beams with characteristics similar to those that will be furnished by SPIRAL. (author)
Heavy-ion optical potential for sub-barrier fusion deduced from a dispersion relation
International Nuclear Information System (INIS)
Kim, B.T.; Kim, H.C.; Park, K.E.
1988-01-01
The heavy-ion energy-dependent optical potentials for the 16 O+ 208 Pb system are deduced from a dispersion relation. These potentials are used to analyze the elastic scattering, fusion, and spin distributions of compound nuclei for the system in a unified way based on the direct reaction theory. It turns out that the energy dependence of the optical potential is essential in explaining the data at near- and sub-barrier energies. The real part of the energy-dependent optical potential deduced was also used in calculating the elastic and fusion cross sections by the conventional barrier penetration model using an incoming wave boundary condition. The predictions of the elastic scattering, fusion cross sections, and the spin distributions of compound nuclei are not satisfactory compared with those from the direct reaction approach. It seems to originate from the fact that this model neglects absorption around the Coulomb barrier region
Coupling constants deduced for the resonances in kaon photo-production
International Nuclear Information System (INIS)
Cheoun, M. K.; Kim, K. S.; Choi, T. K.
2004-01-01
We deduced the coupling constants of nucleon and hyperon resonances, which participate in kaon productions as intermediate states that are formed by electro-magnetic probes and that finally decay into hadronic final states. We used an isobaric model based on an effective Lagrangian approach to describe the processes, in which relevant coupling constants regarding related resonances are effectively determined by fitting available experimental data. Our scheme to deduce the coupling constants was as follows: First, we calculated the lower and the upper limits on the coupling constants by using the experimental decay data available until now and/or theoretical predictions, such as those from quark models and SU(3) symmetry. Second, we exploited those limits as physical constraints on our fitting scheme for the kaon photo-production data. Finally, the deduced values and regions of the coupling constants, which satisfy not only the reaction data but also the decay data, are presented as figures with respect to the strong and the electro-magnetic coupling constants, and their multiplicative values. Our results for the coupling constants give physical values that are more restricted than those allowed by the experimental data nowadays.
International Nuclear Information System (INIS)
Lienard, E.; Ban, G.; Blieck, J.; Durand, D.; Duval, F.; Flechard, X.; Herbane, M.; Labalme, M.; Lemiere, Y.; Mauger, F.; Mery, A.; Naviliat-Cuncic, O.; Rodriguez, D.; Thomas, J. C.
2006-01-01
We report on the status of the LPCTrap experiment, devoted to measure the β-ν angular correlation in the pure Gamow-Teller decay of 6 He. This measurement is motivated by the search for the presence of tensor type contributions to the weak interaction. The 6 He ions are confined in a novel transparent Paul trap. The β particles and the recoil ions are detected in coincidence to deduce the angular correlation parameter. The commissioning run performed in 2005 has given the proof of principle of this experiment. Up to 10 5 coincidences were recorded during a second run in 2006.
Measurement of the electron-neutrino angular correlation in 6He decay
International Nuclear Information System (INIS)
Naviliat-Cuncic, O.; Ban, G.; Durand, D.; Duval, F.; Flechard, X.; Herbane, M.; Labalme, M.; Lienard, E.; Mauger, F.; Mery, A.; Rodriguez-Rubiales, D.
2006-01-01
We report on the status of an experiment aiming to determine the angular correlation coefficient between the electron and the anti-neutrino in the pure Gamow-Teller decay of 6He. Such measurement is motivated by the search for the presence of tensor type contributions to the weak interaction. The experiment uses a setup where 6He ions are confined in a novel transparent Paul trap. Electrons and recoiling ions are detected in coincidence to deduce the angular correlation coefficient. First direct in trap decays have been recorded
International Nuclear Information System (INIS)
Trinder, W.; Adelberger, E.G.; Keller, H.; Krumbholz, K.; Rykaczewski, K.
1994-11-01
The β-decay of 37 Ca has been studied. The half-life was remeasured with improved precision to be 181(1) ms, and β-delayed γ-rays were observed for the first time. The surprisingly high Γ γ /Γ p values for proton-unbound states in 37 K drastically reduce former discrepancies between the Gamow-Teller strength values B(GT) measured in the 37 Ga β-decay and those deduced from the 37 Cl(p, n) 37 Ar mirror reaction. (orig.)
Temporal variability of TEC deduced from groundbased measurements
International Nuclear Information System (INIS)
Mosert, M.; Ezquer, R.G.; Jadur, C.; Radicella, S.M.
2001-01-01
This paper presents a study of the behaviour of the integrated total electron content (ITEC) deduced from electron density profiles of two Argentine stations: Tucuman (26.9 S; 294.6 E) and San Juan (31.5 S; 290.4 E). The ITEC values have been obtained by the technique proposed by Reinisch and Huang (2000). The database includes electron density profiles derived from ionograms recorded at 4 typical hours of the day (00.00, 06.00, 12.00 and 18.00 LT) during different seasonal and solar activity conditions. An analysis of the day to day variability of ITEC has also been done. (author)
Deducing Energy Consumer Behavior from Smart Meter Data
DEFF Research Database (Denmark)
Ebeid, Emad Samuel Malki; Heick, Rune; Jacobsen, Rune Hylsberg
2017-01-01
The ongoing upgrade of electricity meters to smart ones has opened a new market of intelligent services to analyze the recorded meter data. This paper introduces an open architecture and a unified framework for deducing user behavior from its smart main electricity meter data and presenting...... the results in a natural language. The framework allows a fast exploration and integration of a variety of machine learning algorithms combined with data recovery mechanisms for improving the recognition’s accuracy. Consequently, the framework generates natural language reports of the user’s behavior from...
Atmospheric response to Saharan dust deduced from ECMWF reanalysis increments
Kishcha, P.; Alpert, P.; Barkan, J.; Kirchner, I.; Machenhauer, B.
2003-04-01
This study focuses on the atmospheric temperature response to dust deduced from a new source of data - the European Reanalysis (ERA) increments. These increments are the systematic errors of global climate models, generated in reanalysis procedure. The model errors result not only from the lack of desert dust but also from a complex combination of many kinds of model errors. Over the Sahara desert the dust radiative effect is believed to be a predominant model defect which should significantly affect the increments. This dust effect was examined by considering correlation between the increments and remotely-sensed dust. Comparisons were made between April temporal variations of the ERA analysis increments and the variations of the Total Ozone Mapping Spectrometer aerosol index (AI) between 1979 and 1993. The distinctive structure was identified in the distribution of correlation composed of three nested areas with high positive correlation (> 0.5), low correlation, and high negative correlation (Forecast(ECMWF) suggests that the PCA (NCA) corresponds mainly to anticyclonic (cyclonic) flow, negative (positive) vorticity, and downward (upward) airflow. These facts indicate an interaction between dust-forced heating /cooling and atmospheric circulation. The April correlation results are supported by the analysis of vertical distribution of dust concentration, derived from the 24-hour dust prediction system at Tel Aviv University (website: http://earth.nasa.proj.ac.il/dust/current/). For other months the analysis is more complicated because of the essential increasing of humidity along with the northward progress of the ITCZ and the significant impact on the increments.
Physics-based Inverse Problem to Deduce Marine Atmospheric Boundary Layer Parameters
2017-03-07
knowledge and capabilities in the use and development of inverse problem techniques to deduce atmospheric parameters. WORK COMPLETED The research completed...please find the Final Technical Report with SF 298 for Dr. Erin E. Hackett’s ONR grant entitled Physics -based Inverse Problem to Deduce Marine...From- To) 07/03/2017 Final Technica l Dec 2012- Dec 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Physics -based Inverse Problem to Deduce Marine
Isospin mixing in the ground state of sup 5 sup 2 Mn
Schuurmans, P; Phalet, T; Severijns, N; Vereecke, B; Versyck, S
2000-01-01
The presence of isospin mixing into the ground state of sup 5 sup 2 Mn was studied via anisotropic positron emission from nuclei. With this method the isospin forbidden Fermi-component in the Gamow-Teller dominated beta decay was determined. It is shown that sample purity and the control of positron scattering is of vital importance. Comparison between theory and experiment shows that shell model calculations of the isospin mixing probability deviate by a factor three to seven from experiment. For more recent Hartree-Fock-RPA based calculations the difference is over two orders of magnitude.
Energy Technology Data Exchange (ETDEWEB)
Courtin, S.; Baumann, P.; Dessagne, Ph.; Marechal, F.; Miehe, Ch.; Perrot, F.; Poirier, E.; Ramdhane, M. [Institut de Recherches Subatomiques, Strasbourg Cedex 2 (France); ISOLDE collaboration
2004-09-15
This paper describes two beta decay experiments performed at the CERN/ISOLDE mass separator. The structure of {sup 74}Kr has been studied using a total absorption {gamma} spectrometer (TAgS). The measured Gamow-Teller strength is presented and compared to HFBCS+QRPA calculations. The {sup 33}Na decay is also presented. The structure of the {sup 33}Mg daughter nucleus is compared to shell-model calculations, showing for the first time an inversion of states in the A{sub {approx}}35 mass region. (author)
Beta-decay strength and isospin mixing studies in the sd and fp-shells
International Nuclear Information System (INIS)
Jokinen, A.; Aeystoe, J.; Dendooven, P.; Honkanen, A.; Lipas, P.; Peraejaervi, K.; Oinonen, M.; Siiskonen, T.
1998-01-01
We have studied beta decays of M T 41 Ti shows a large, 10(8) %, isospin mixing of IAS and the Gamow-Teller strength is observed to be quenched by a factor of q 2 =0.64. These results can be reproduced qualitatively in our shell model calculations. We have observed for the first time proton and gamma decay of the isobaric analogue state in 23 Mg. Our results on the isospin mixing of the isobaric analogue state agrees well with the shell model calculations. The obtained proton branch of the IAS is used to extract the transition strength for the reaction 22 Na(p,γ) 23 Mg
Energy Technology Data Exchange (ETDEWEB)
Kucuk, L.; Oktem, Y.; Cakirli, R.B.; Ganioglu, E.; Susoy, G. [Istanbul University, Department of Physics, Istanbul (Turkey); Orrigo, S.E.A.; Montaner-Piza, A.; Rubio, B. [CSIC-Universidad de Valencia, Instituto de Fisica Corpuscular, Valencia (Spain); Fujita, Y. [Osaka University, Department of Physics, Toyonaka, Osaka (Japan); Osaka University, Research Center for Nuclear Physics, Ibaraki, Osaka (Japan); Gelletly, W. [CSIC-Universidad de Valencia, Instituto de Fisica Corpuscular, Valencia (Spain); University of Surrey, Department of Physics, Guildford, Surrey (United Kingdom); Blank, B.; Ascher, P.; Giovinazzo, J.; Grevy, S. [Centre d' Etudes Nucleaires de Bordeaux Gradignan, CNRS/IN2P3 - Universite de Bordeaux, Gradignan (France); Adachi, T.; Fujita, H.; Tamii, A. [Osaka University, Research Center for Nuclear Physics, Ibaraki, Osaka (Japan); Algora, A. [CSIC-Universidad de Valencia, Instituto de Fisica Corpuscular, Valencia (Spain); Inst. of Nuclear Research of the Hung. Acad. of Sciences, Debrecen (Hungary); France, G. de; Oliveira Santos, F. de; Thomas, J.C. [Grand Accelerateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Caen (France); Marques, F.M. [Laboratoire de Physique Corpusculaire de Caen, ENSICAEN, UNICAEN, IN2P3/CNRS, Caen (France); Molina, F. [CSIC-Universidad de Valencia, Instituto de Fisica Corpuscular, Valencia (Spain); Comision Chilena de Energia Nuclear, Casilla 188-D, Santiago (Chile); Perrot, L. [IPN Orsay, Orsay (France); Raabe, R. [Grand Accelerateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Caen (France); KU Leuven, Instituut voor Kern- en Stralingsfysica, Leuven (Belgium); Srivastava, P.C. [Grand Accelerateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Caen (France); Indian Institute of Technology, Department of Physics, Roorkee (India)
2017-06-15
We have measured the β-decay half-lives of 16 neutron-deficient nuclei with T{sub z} = -1/2 and -1, ranging from chromium to germanium. They were produced in an experiment carried out at GANIL and optimized for the production of {sup 58}Zn, for which in addition we present the decay scheme and absolute Fermi and Gamow-Teller transition strengths. Since all of these nuclei lie on the rp-process pathway, the T{sub 1/2} values are important ingredients for the rp-process reaction flow calculations and for models of X-ray bursters. (orig.)
Description of the Gamov-Teller β+-decay of tin isotopes
International Nuclear Information System (INIS)
Kuz'min, V.A.; Solov'ev, V.G.
1988-01-01
The integrated log(ft) values of Gamow-Teller β + decays of the neutron-deficient tine isotopes are calculated in the random phase approximation with particle-hole and particle-particle residual interactions which parameters have been fixed earlier. For |g A /g V |=1 and |g A /g V |=1.263 a good correspondence with the experimental data is obtained for 104,106,108 Sn and a prediction is made for 102 Sn. It is shown that one cannot define from the rate of neutron-deficient nuclei β + decay the renormalization of the axial-vector weak interaction constant g A
Multipole decomposition analysis of the 27Al, 90Zr, 208Pb(p, n) reactions at 295 MeV
International Nuclear Information System (INIS)
Wakasa, T.; Greenfield, M.B.; Koori, N.; Okihana, A.; Hatanaka, K.
1996-01-01
Differential cross sections at θ lab between 0 and 15 and the polarization transfer D NN at zero degrees for the 27 Al, 90 Zr, 208 Pb(p,n) reactions are measured at a bombarding energy of 295 MeV. A multipole decomposition (MD) technique is applied to extract L=0, L=1, and L≥2 contributions to the cross sections. The summed Gamow-Teller strength B(GT) is compared with shell-model calculations for the 27 Al(p,n) and 90 Zr(p,n) reactions. The usefulness of the polarization transfer observable in the MD analysis is discussed. (orig.)
Marechal, F; Caballero ontanaya, L
2002-01-01
In the framework of the investigation of the shapes of the ground states of the parent nucleus, we propose to carry out measurements of the complete Gamow-Teller strength distribution for the $^{76-80}$Sr isotopes, with a new Total Absorption Gamma Spectrometer installed on a new beam line. The results will be compared with theoretical calculations based on the mean field approach. A brief report on the IS370 experiment on $^{72-75}$Kr decay, which was recently performed at ISOLDE, will be given and the performance of the sum spectrometer will be presented.
International Nuclear Information System (INIS)
De Oliveira, Z.M.
1980-01-01
A detailed analysis of the simple statistical model description for delayed neutron emission of 87 Br, 137 I, 85 As and 135 Sb has been performed. In agreement with experimental findings, structure in the #betta#-strength function is required to reproduce the envelope of the neutron spectrum from 87 Br. For 85 As and 135 Sb the model is found incapable of simultaneously reproducing envelopes of delayed neutron spectra and neutron branching ratios to excited states in the final nuclei for any choice of #betta#-strength function. The results indicate that partial widths for neutron emission are not compatible with optical-model transmission coefficients. The simple shell model with pairing is shown to qualitatively describe the main features of the #betta#-strength functions for decay of 87 Br and 91 93 95 97 Rb. It is found that the location of apparent resonances in the experimental data are in rough agreement with the location of centroids of strength calculated with this model. An extension of the shell model picture which includes the Gamow-Teller residual interaction is used to investigate decay properties of 84 86 As, 86 92 Br and 88 102 Rb. For a realistic choice of interaction strength, the half lives of these isotopes are fairly well reproduced and semiquantitative agreement with experimental #betta#-strength functions is found. Delayed neutron emission probabilities are reproduced for precursors nearer stability with systematic deviations being observed for the heavier nuclei. Contrary to the assumption of a structureless Gamow-Teller giant resonance as embodied gross theory of #betta#-decay, we find that structures in the tail of the Gamow-Teller giant resonances are expected which strongly influence the decay properties of nuclides in this region
Nuclear spin and isospin excitations
International Nuclear Information System (INIS)
Osterfeld, F.
1992-01-01
A review is given of our present knowledge of collective spin-isospin excitations in nuclei. Most of this knowledge comes from intermediate-energy charge-exchange reactions and from inelastic electron- and proton-scattering experiments. The nuclear-spin dynamics is governed by the spin-isospin-dependent two-nucleon interaction in the medium. This interaction gives rise to collective spin modes such as the giant Gamow-Teller resonances. An interesting phenomenon is that the measured total Gamow-Teller transition strength in the resonance region is much less than a model-independent sum rule predicts. Two physically different mechanisms have been discussed to explain this so-called quenching of the total Gamow-Teller strength: coupling to subnuclear degrees of freedom in the form of Δ-isobar excitation and ordinary nuclear configuration mixing. Both detailed nuclear structure calculations and extensive analyses of the scattering data suggest that the nuclear configuration mixing effect is the more important quenching mechanism, although subnuclear degrees of freedom cannot be ruled out. The quenching phenomenon occurs for nuclear-spin excitations at low excitation energies (ω∼10--20 MeV) and small-momentum transfers (q≤0.5 fm -1 ). A completely opposite effect is anticipated in the high (ω,q)-transfer region (0≤ω≤500 MeV, 0.5≤q≤3 fm -1 ). The nuclear spin-isospin response might be enhanced due to the attractive pion field inside the nucleus. Charge-exchange reactions at GeV incident energies have been used to study the quasifree peak region and the Δ-resonance region. An interesting result of these experiments is that the Δ excitation in the nucleus is shifted downwards in energy relative to the Δ excitation of the free proton
Hydraulics of subaqueous ash flows as deduced from their deposits
Doronzo, Domenico M.; Dellino, Pierfrancesco
2012-09-01
Subaqueous ash flows are gravity currents consisting of a mixture of sea water and ash particles. Also called volcaniclastic turbidity currents (VTCs), they can be generated because of remobilization of pyroclastic fall deposits, which are emplaced into the sea around a volcanic island, as well as far away, during an explosive eruption. The VTC upper part is the turbulent transport system for the flow, whereas the viscous basal one is the depositional system. Typical sequences of VTC deposits are characterized by cross-laminations, planar and convolute laminations, and massive beds, which reflect the stratified nature of the flow. Here, the analysis of some VTC hydraulic parameters is presented in order to depict flow behavior and sedimentation during deposition. A reverse engineering approach is proposed, which consists of calculating hydraulic parameters by starting from deposit features. The calculated values show that a VTC is homogeneously-turbulent for most of the thickness, but is viscous at its base. First, cross-laminations are directly acquired over the rough pre-existing seafloor, then planar or convolute laminations aggrade over the newly formed substrate. Finally, fine-grained suspended particles gently settle and cap the flow deposit.
Shell structure of potassium isotopes deduced from their magnetic moments
Papuga, J.; Kreim, K; Barbieri, C; Blaum, K; De Rydt, M; Duguet, T; Garcia Ruiz, R F; Heylen, H; Kowalska, M; Neugart, R; Neyens, G; Nortershauser, W; Rajabali, M M; Sanchez, R; Smirnova, N; Soma, V; Yordanov, D T
2014-09-29
$\\textbf{Background:}$ Ground-state spins and magnetic moments are sensitive to the nuclear wave function, thus they are powerful probes to study the nuclear structure of isotopes far from stability. \\\\ \\\\ $\\textbf{Purpose:}$ Extend our knowledge about the evolution of the $1/2^+$ and $3/2^+$ states for K isotopes beyond the $N = 28$ shell gap. \\\\ \\\\ $\\textbf{Method:}$ High-resolution collinear laser spectroscopy on bunched atomic beams. \\\\ \\\\ $\\textbf{Results:}$ From measured hyperfine structure spectra of K isotopes, nuclear spins and magnetic moments of the ground states were obtained for isotopes from $N = 19$ up to $N = 32$. In order to draw conclusions about the composition of the wave functions and the occupation of the levels, the experimental data were compared to shell-model calculations using SDPF-NR and SDPF-U effective interactions. In addition, a detailed discussion about the evolution of the gap between proton $1d_{3/2}$ and $2s_{1/2}$ in the shell model and $\\textit{ab initio}$ framework is al...
Deducing T, C, and P invariance for strong interactions in topological particle theory
International Nuclear Information System (INIS)
Jones, C.E.
1985-01-01
It is shown here how the separate discrete invariances [time reversal (T), charge conjugation (C), and parity (P)] in strong interactions can be deduced as consequences of other S-matrix requirements in topological particle theory
Nuclear structure of light thallium isotopes as deduced from laser spectroscopy on a fast atom beam
International Nuclear Information System (INIS)
Bounds, J.A.
1985-08-01
After optimizing the system by experiments on /sup 201,203,205/Tl, the neutron-deficient isotopes 189-193 Tl have been studied using the collinear fast atom beam laser spectroscopy system at UNISOR on-line to the Holifield Heavy Ion Research Facility. A sensitive system for the measurements was developed since the light isotopes were available in mass-separated beams of only 7 x 10 4 to 4 x 10 5 atoms per second. By laser excitation of the 535 nm atomic transitions of atoms in the beam, the 6s 2 7s 2 S/sub 1/2/ and 6s 2 6s 2 P/sub 3/2/ hyperfine structures were measured, as were the isotope shifts of the 535 nm transitions. From these, the magnetic dipole moments, spectroscopic quadrupole moments and isotopic changes in mean-square charge radius were deduced. The magnetic dipole moments are consistent with previous data. The /sup 190,192/Tl isotopes show a considerable difference in quadrupole deformations as well as an anomalous isotope shift with respect to 194 Tl. A large isomer shift in 193 Tl is observed implying a larger deformation in the 9/2 - isomer than in the 1/2 + ground state. The /sup 189,191,193/Tl isomers show increasing deformation away from stability. A deformed shell model calculation indicates that this increase in deformation can account for the dropping of the 9/2 - band in these isotopes while an increase in neutron pairing correlations, having opposite and compensating effects on the rotational moment of inertia, maintains the 9/2 - strong-coupled band structure. 105 refs., 27 figs
Method of estimating horizontal vectors of ionospheric electric field deduced from HF Doppler data
International Nuclear Information System (INIS)
Tsutsui, M.; Ogawa, T.; Kamide, Y.; Kroehl, H.W.; Hausman, B.A.
1988-01-01
An HF Doppler method for estimating the time variations of the horizontal electric field in the ionosphere is presented which takes into account, for long-lasting variations in the electric field, the effect of electron decay due to attachment and/or recombination processes. The method is applied to an isolated substorm event, using equivalent ionospheric current systems deduced from worldwide magnetometer data in the estimations. The present results are found to agree with data deduced from current systems and high latitude electrojet activity. 18 references
Uncertainties in constraining low-energy constants from {sup 3}H β decay
Energy Technology Data Exchange (ETDEWEB)
Klos, P.; Carbone, A.; Hebeler, K. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Menendez, J. [University of Tokyo, Department of Physics, Tokyo (Japan); Schwenk, A. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)
2017-08-15
We discuss the uncertainties in constraining low-energy constants of chiral effective field theory from {sup 3}H β decay. The half-life is very precisely known, so that the Gamow-Teller matrix element has been used to fit the coupling c{sub D} of the axial-vector current to a short-range two-nucleon pair. Because the same coupling also describes the leading one-pion-exchange three-nucleon force, this in principle provides a very constraining fit, uncorrelated with the {sup 3}H binding energy fit used to constrain another low-energy coupling in three-nucleon forces. However, so far such {sup 3}H half-life fits have only been performed at a fixed cutoff value. We show that the cutoff dependence due to the regulators in the axial-vector two-body current can significantly affect the Gamow-Teller matrix elements and consequently also the extracted values for the c{sub D} coupling constant. The degree of the cutoff dependence is correlated with the softness of the employed NN interaction. As a result, present three-nucleon forces based on a fit to {sup 3}H β decay underestimate the uncertainty in c{sub D}. We explore a range of c{sub D} values that is compatible within cutoff variation with the experimental {sup 3}H half-life and estimate the resulting uncertainties for many-body systems by performing calculations of symmetric nuclear matter. (orig.)
Impact of electron-captures on nuclei near N = 50 on core-collapse supernovae
Titus, R.; Sullivan, C.; Zegers, R. G. T.; Brown, B. A.; Gao, B.
2018-01-01
The sensitivity of the late stages of stellar core collapse to electron-capture rates on nuclei is investigated, with a focus on electron-capture rates on 74 nuclei with neutron number close to 50, just above doubly magic 78Ni. It is demonstrated that variations in key characteristics of the evolution, such as the lepton fraction, electron fraction, entropy, stellar density, and in-fall velocity are about 50% due to uncertainties in the electron-capture rates on nuclei in this region, although thousands of nuclei are included in the simulations. The present electron-capture rate estimates used for the nuclei in this high-sensitivity region of the chart of isotopes are primarily based on a simple approximation, and it is shown that the estimated rates are likely too high, by an order of magnitude or more. Electron-capture rates based on Gamow-Teller strength distributions calculated in microscopic theoretical models will be required to obtain better estimates. Gamow-Teller distributions extracted from charge-exchange experiments performed at intermediate energies serve to guide the development and benchmark the models. A previously compiled weak-rate library that is used in the astrophysical simulations was updated as part of the work presented here, by adding additional rate tables for nuclei near stability for mass numbers between 60 and 110.
Contribution of the radioactive decay to the study of the structure of N=Z nuclei of mass A>70
International Nuclear Information System (INIS)
Longour, Christophe
1999-01-01
Radioactive decay study gives an access to the interaction which rules the β decay process as well as the structure of the nuclear states involved. This work describes the observation of the decay of N = Z nuclei with mass A > 70. For the odd-odd N = Z nuclei 78 Y, 82 Nb and 86 Tc, the decay has been established as superallowed Fermi type transitions. The results pave the way for more precise measurements and extend the mass range nowadays used to understand the behaviour of the weak interaction in the nuclear matter. The observation of the decay of the even-even N = Z 72 Kr leads us to build the Gamow-Teller strength distribution from which some clues about the ground state deformation of this isotope can be obtained. More complete experimental observation and some developments of the calculations used to interpret the distribution of the Gamow-Teller strength are needed. Finally, this work describes the developments and tests of a prototype detector the aim of which to determine the contribution of β particles to energy distribution observed in germanium detector. The tests we have performed show that this prototype can identify and reject 80% of the β particles emitted by a source with a 2,3 MeV end-point. The very satisfactory performances of this prototype need now to be confirmed under experimental conditions. (author)
Complete amino acid sequence of human intestinal aminopeptidase N as deduced from cloned cDNA
DEFF Research Database (Denmark)
Cowell, G M; Kønigshøfer, E; Danielsen, E M
1988-01-01
The complete primary structure (967 amino acids) of an intestinal human aminopeptidase N (EC 3.4.11.2) was deduced from the sequence of a cDNA clone. Aminopeptidase N is anchored to the microvillar membrane via an uncleaved signal for membrane insertion. A domain constituting amino acid 250...
CONSISTENT USE OF THE KALMAN FILTER IN CHEMICAL TRANSPORT MODELS (CTMS) FOR DEDUCING EMISSIONS
Past research has shown that emissions can be deduced using observed concentrations of a chemical, a Chemical Transport Model (CTM), and the Kalman filter in an inverse modeling application. An expression was derived for the relationship between the "observable" (i.e., the con...
Calculation of saturated hydraulic conductivity of bentonite
International Nuclear Information System (INIS)
He Jun
2006-01-01
Hydraulic conductivity test has some defects such as weak repeatability, time-consuming. Taking bentonite as dual porous media, the calculation formula of the distance, d 2 , between montmorillonite in intraparticle pores is deduced. Improved calculated method of hydraulic conductivity is obtained using d 2 and Poiseuille law. The method is valid through the comparison with results of test and other methods. The method is very convenient to calculate hydraulic conductivity of bentonite of certain montmorillonite content and void ratio. (authors)
International Nuclear Information System (INIS)
Poveda, Ana; Asensio, Juan Luis; Martin-Pastor, Manuel; Jimenez-Barbero, Jesus
1997-01-01
1 H-NMR cross-relaxation rates and nonselective longitudinal relaxation times have been obtained at two magnetic fields (7.0 and 11.8 T) and at a variety of temperatures for the branched tetrasaccharide methyl 3-O-α-N-acetyl-galactosaminyl-β-galactopyranosyl-(1 → 4)[3-O-α-fucosyl] -glucopyranoside (1), an inhibitor of astrocyte growth. In addition, 13 C-NMR relaxation data have also been recorded at both fields. The 1 H-NMR relaxation data have been interpreted using different motional models to obtain proton-proton correlation times. The results indicate that the GalNAc and Fuc rings display more extensive local motion than the two inner Glc and Gal moieties, since those present significantly shorter local correlation times. The 13 C-NMR relaxation parameters have been interpreted in terms of the Lipari-Szabo model-free approach. Thus, order parameters and internal motion correlation times have been deduced. As obtained for the 1 H-NMR relaxation data, the two outer residues possess smaller order parameters than the two inner rings. Internal correlation times are in the order of 100 ps. The hydroxymethyl groups have also different behaviour,with the exocyclic carbon on the glucopyranoside unit showing the highestS 2 . Molecular dynamics simulations using a solvated system have also been performed and internal motion correlation functions have been deduced from these calculations. Order parameters and interproton distances have been compared to those inferred from the NMR measurements. The obtained results are in fair agreement with the experimental data
Energy Technology Data Exchange (ETDEWEB)
Poveda, Ana [Universidad Autonoma de Madrid, Servicio Interdepartamental de Investigacion (Spain); Asensio, Juan Luis; Martin-Pastor, Manuel; Jimenez-Barbero, Jesus [Instituto de Quimica Organica, CSIC, Grupo de Carbohidratos (Spain)
1997-07-15
{sup 1}H-NMR cross-relaxation rates and nonselective longitudinal relaxation times have been obtained at two magnetic fields (7.0 and 11.8 T) and at a variety of temperatures for the branched tetrasaccharide methyl 3-O-{alpha}-N-acetyl-galactosaminyl-{beta}-galactopyranosyl-(1{sup {yields}}4)[3-O-{alpha}-fucosyl] -glucopyranoside (1), an inhibitor of astrocyte growth. In addition, {sup 13}C-NMR relaxation data have also been recorded at both fields. The {sup 1}H-NMR relaxation data have been interpreted using different motional models to obtain proton-proton correlation times. The results indicate that the GalNAc and Fuc rings display more extensive local motion than the two inner Glc and Gal moieties, since those present significantly shorter local correlation times. The{sup 13}C-NMR relaxation parameters have been interpreted in terms of the Lipari-Szabo model-free approach. Thus, order parameters and internal motion correlation times have been deduced. As obtained for the{sup 1}H-NMR relaxation data, the two outer residues possess smaller order parameters than the two inner rings. Internal correlation times are in the order of 100 ps. The hydroxymethyl groups have also different behaviour,with the exocyclic carbon on the glucopyranoside unit showing the highestS{sup 2}. Molecular dynamics simulations using a solvated system have also been performed and internal motion correlation functions have been deduced from these calculations. Order parameters and interproton distances have been compared to those inferred from the NMR measurements. The obtained results are in fair agreement with the experimental data.
Directory of Open Access Journals (Sweden)
C. M. Hall
Full Text Available By measuring fading times of radar echoes from underdense meteor trails, it is possible to deduce the ambipolar diffusivities of the ions responsible for these radar echoes. It could be anticipated that these diffusivities increase monotonically with height akin to neutral viscosity. In practice, this is not always the case. Here, we investigate the capability of neutral turbulence to affect the meteor trail diffusion rate.
Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; turbulence
Directory of Open Access Journals (Sweden)
C. M. Hall
2002-11-01
Full Text Available By measuring fading times of radar echoes from underdense meteor trails, it is possible to deduce the ambipolar diffusivities of the ions responsible for these radar echoes. It could be anticipated that these diffusivities increase monotonically with height akin to neutral viscosity. In practice, this is not always the case. Here, we investigate the capability of neutral turbulence to affect the meteor trail diffusion rate.Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; turbulence
Comparisons of Satellite-Deduced Overlapping Cloud Properties and CALIPSO CloudSat Data
Chang, Fu-Lung; Minnis, Patrick; Lin, Bing; Sun-Mack, Sunny
2010-01-01
Introduction to the overlapped cloud properties derived from polar-orbiting (MODIS) and geostationary (GOES-12, -13, Meteosat-8, -9, etc.) meteorological satellites, which are produced at the NASA Langley Research Center (LaRC) cloud research & development team (NASA lead scientist: Dr. Patrick Minnis). Comparison of the LaRC CERES MODIS Edition-3 overlapped cloud properties to the CALIPSO and the CloudSat active sensing data. High clouds and overlapped clouds occur frequently as deduced by CALIPSO (44 & 25%), CloudSat (25 & 4%), and MODIS (37 & 6%). Large fractions of optically-thin cirrus and overlapped clouds are deduced from CALIPSO, but much smaller fractions are from CloudSat and MODIS. For overlapped clouds, the averaged upper-layer CTHs are about 12.8 (CALIPSO), 10.9 (CloudSat) and 10 km (MODIS), and the averaged lower-layer CTHs are about 3.6 (CALIPSO), 3.2 (CloudSat) and 3.9 km (MODIS). Based on comparisons of upper and lower-layer cloud properties as deduced from the MODIS, CALIPSO and CloudSat data, more enhanced passive satellite methods for retrieving thin cirrus and overlapped cloud properties are needed and are under development.
Horvath, Monica M; Winfield, Stephanie; Evans, Steve; Slopek, Steve; Shang, Howard; Ferranti, Jeffrey
2011-04-01
In many healthcare organizations, comparative effectiveness research and quality improvement (QI) investigations are hampered by a lack of access to data created as a byproduct of patient care. Data collection often hinges upon either manual chart review or ad hoc requests to technical experts who support legacy clinical systems. In order to facilitate this needed capacity for data exploration at our institution (Duke University Health System), we have designed and deployed a robust Web application for cohort identification and data extraction--the Duke Enterprise Data Unified Content Explorer (DEDUCE). DEDUCE is envisioned as a simple, web-based environment that allows investigators access to administrative, financial, and clinical information generated during patient care. By using business intelligence tools to create a view into Duke Medicine's enterprise data warehouse, DEDUCE provides a Guided Query functionality using a wizard-like interface that lets users filter through millions of clinical records, explore aggregate reports, and, export extracts. Researchers and QI specialists can obtain detailed patient- and observation-level extracts without needing to understand structured query language or the underlying database model. Developers designing such tools must devote sufficient training and develop application safeguards to ensure that patient-centered clinical researchers understand when observation-level extracts should be used. This may mitigate the risk of data being misunderstood and consequently used in an improper fashion. Copyright © 2010 Elsevier Inc. All rights reserved.
Taddeucci, T. N.; Rapaport, J.; Bainum, D. E.; Goodman, C. D.; Foster, C. C.; Gaarde, C.; Larsen, J.; Goulding, C. A.; Horen, D. J.; Masterson, T.; Sugarbaker, E.
1982-02-01
Information concerning the ratio of the isovector effective interaction strengths |JστJτ| may be obtained from the ratio of (p,n) Gamow-Teller and isobaric analog state 0° differential cross sections. We have examined 0° (p,n) data for the energy range 5-200 MeV and find that for energies larger than 50 MeV and for targets with A=7-42 the product of the interaction-strength and distortion-factor ratios |JστJτ|(NστNτ)12 appears to be mass independent and linear as a function of bombarding energy. NUCLEAR REACTIONS 7Li, 13, 14C, 26Mg, 37Cl, 41Ca(p,n), measured σ(θ=0°), GT, IAS transitions, Ep=60-200 MeV. Deduced energy dependence, interaction strength ratio |JστJτ|.
International Nuclear Information System (INIS)
Rosen, S.P.
1990-01-01
I review the intrinsic properties of neutrinos as deduced from cosmological, astrophysical, and laboratory experiments. Bounds on magnetic moments and theoretical models which yield large moments but small masses are briefly discussed. The MSW solution to the solar neutrino problem is reviewed in light of the existing data from the 37 Cl and Kamiokande II experiments. The combined data disfavor the adiabatic solution and tend to support either the large angle solution or the nonadiabatic one. In the former case the 71 Ga signal will be suppressed by the same factor as for 37 Cl, and in the latter case the suppression factor could be as large as 10 or more. 41 refs
Dotaciones para la recuperación de activos revertibles como deducibles del impuesto sobre sociedades
Duplá Marín, María José
2001-01-01
El objetivo final que nos propusimos con este trabajo de investigación fue profundizar en el estudio jurídico-tributario de las dotaciones al fondo de reversión como gasto deducible para determinar la base imponible del impuesto sobre sociedades, en aquellas sociedades concesionarias de servicios públicos con cláusula de reversión de activos, partiendo de su realidad contable.En consecuencia el trabajo se ciñe al estudio crítico de la regulación jurídica del fondo de reversión como gasto fisc...
Deducing the kinetics of protein synthesis in vivo from the transition rates measured in vitro.
Directory of Open Access Journals (Sweden)
Sophia Rudorf
2014-10-01
Full Text Available The molecular machinery of life relies on complex multistep processes that involve numerous individual transitions, such as molecular association and dissociation steps, chemical reactions, and mechanical movements. The corresponding transition rates can be typically measured in vitro but not in vivo. Here, we develop a general method to deduce the in-vivo rates from their in-vitro values. The method has two basic components. First, we introduce the kinetic distance, a new concept by which we can quantitatively compare the kinetics of a multistep process in different environments. The kinetic distance depends logarithmically on the transition rates and can be interpreted in terms of the underlying free energy barriers. Second, we minimize the kinetic distance between the in-vitro and the in-vivo process, imposing the constraint that the deduced rates reproduce a known global property such as the overall in-vivo speed. In order to demonstrate the predictive power of our method, we apply it to protein synthesis by ribosomes, a key process of gene expression. We describe the latter process by a codon-specific Markov model with three reaction pathways, corresponding to the initial binding of cognate, near-cognate, and non-cognate tRNA, for which we determine all individual transition rates in vitro. We then predict the in-vivo rates by the constrained minimization procedure and validate these rates by three independent sets of in-vivo data, obtained for codon-dependent translation speeds, codon-specific translation dynamics, and missense error frequencies. In all cases, we find good agreement between theory and experiment without adjusting any fit parameter. The deduced in-vivo rates lead to smaller error frequencies than the known in-vitro rates, primarily by an improved initial selection of tRNA. The method introduced here is relatively simple from a computational point of view and can be applied to any biomolecular process, for which we have
International Nuclear Information System (INIS)
Wakasa, Tomotsugu
1997-01-01
We have measured a complete set of polarization transfer observables has been measured for quasi-free (p vector, n vector) reactions on 2 H, 6 Li, 12 C, 40 Ca, and 208 Pb at a bombarding energy of 346MeV and a laboratory scattering angle of 22deg (q=1.7 fm -1 ). The polarization transfer observables for all five targets are remarkably similar. These polarization observables yield separated spin-longitudinal (σ·q) and spin-transverse (σxq) nuclear responses. These results are compared to the spin-transverse responses measured in deep-inelastic electron scattering as well as to nuclear responses based on the random phase approximation. Such a comparison reveals an enhancement in the (p vector, n vector) spin-transverse channel, which masks the effect of pionic correlations in the response ratio. Second, the double differential cross sections at θ lab between 0deg and 12.3deg and the polarization transfer D NN at 0deg for the 90 Zr(p,n) reaction are measured at a bombarding energy of 295MeV. The Gamow-Teller(GT) strength B(GT) in the continuum deduced from the L=0 cross section is compared both with the perturbative calculation by Bertsch and Hamamoto and with the second-order random phase approximation calculation by Drozdz et al. The sum of B(GT) values up to 50MeV excitation becomes S β- =28.0±1.6 after subtracting the contribution of the isovector spin-monopole strength. This S β- value of 28.0±1.6 corresponds to about (93±5)% of the minimum value of the sum-rule 3(N-Z)=30. Last, first measurements of D NN (0deg) for (p vector, n vector) reactions at 295MeV yield large negative values up to 50MeV excitation for the 6 Li, 11 B, 12 C, 13 C(p vector, n vector) reactions. DWIA calculations using the Franey and Love (FL) 270MeV interaction reproduce differential cross sections and D NN (0deg) values, while the FL 325MeV interaction yield D NN (0deg) values less negative than the experimental values. (J.P.N.)
Ivanov, Yurii P.
2014-02-14
The magneto-optic Kerr effect has been employed to determine the magnetization process and estimate the domain structure of microwires with circular magnetic anisotropy. The diameter of microwires was 8 μm, and pieces 2 cm long were selected for measurements. The analysis of the local surface longitudinal and transverse hysteresis loops has allowed us to deduce a vortex magnetic structure with axial core and circular external shell. Moreover, a bamboo-like surface domain structure is confirmed with wave length of around 10 to 15 μm and alternating chirality in adjacent circular domains. The width of the domain wall is estimated to be less than 3 μm. Finally, closure domain structures with significant helical magnetization component are observed extending up to around 1000 μm from the end of the microwire.
Deducing the pathogenic contribution of recessive ABCA4 alleles in an outbred population.
Schindler, Emily I; Nylen, Erik L; Ko, Audrey C; Affatigato, Louisa M; Heggen, Andrew C; Wang, Kai; Sheffield, Val C; Stone, Edwin M
2010-10-01
Accurate prediction of the pathogenic effects of specific genotypes is important for the design and execution of clinical trials as well as for meaningful counseling of individual patients. However, for many autosomal recessive diseases, it can be difficult to deduce the relative pathogenic contribution of individual alleles because relatively few affected individuals share the same two disease-causing variations. In this study, we used multiple regression analysis to estimate the pathogenicity of specific alleles of ABCA4 in patients with retinal phenotypes ranging from Stargardt disease to retinitis pigmentosa. This analysis revealed quantitative allelic effects on two aspects of the visual phenotype, visual acuity (P disease and will also aid in the optimal selection of subjects for clinical trials of new therapies.
Arman, Samuel D; Prideaux, Gavin J
2016-02-15
The marsupial lion, Thylacoleo carnifex, was the largest-ever marsupial carnivore, and is one of the most iconic extinct Australian vertebrates. With a highly-specialised dentition, powerful forelimbs and a robust build, its overall morphology is not approached by any other mammal. However, despite >150 years of attention, fundamental aspects of its biology remain unresolved. Here we analyse an assemblage of claw marks preserved on surfaces in a cave and deduce that they were generated by marsupial lions. The distribution and skewed size range of claw marks within the cave elucidate two key aspects of marsupial lion biology: they were excellent climbers and reared young in caves. Scrutiny of >10,000 co-located Pleistocene bones reveals few if any marsupial lion tooth marks, which dovetails with the morphology-based interpretation of the species as a flesh specialist.
Ivanov, Yurii P.; del Real, R. P.; Chubykalo-Fesenko, O.; Vá zquez, M.
2014-01-01
The magneto-optic Kerr effect has been employed to determine the magnetization process and estimate the domain structure of microwires with circular magnetic anisotropy. The diameter of microwires was 8 μm, and pieces 2 cm long were selected for measurements. The analysis of the local surface longitudinal and transverse hysteresis loops has allowed us to deduce a vortex magnetic structure with axial core and circular external shell. Moreover, a bamboo-like surface domain structure is confirmed with wave length of around 10 to 15 μm and alternating chirality in adjacent circular domains. The width of the domain wall is estimated to be less than 3 μm. Finally, closure domain structures with significant helical magnetization component are observed extending up to around 1000 μm from the end of the microwire.
International Nuclear Information System (INIS)
Srinivasan, M.; SubbaRao, K.; Garg, S.B.; Acharya, G.V.
1989-01-01
The authors describe a number of interesting systematics and correlations deduced by analyzing the criticality data of special actinide nuclides using concepts embodied in the Trombay critically formula (TCF). The κ ∞ of fast metal actinide nuclides gives a remarkable linear correlation with the fissility parameter Z 2 /A. The neutron leakage probability of all fast metal cores characterized using a constant parameter σ std enables computation of the critical mass value of any unknown fissile nuclide knowing only its Z 2 /A value. Since the neutron leakage probability from dilute fissile solutions is primarily governed by the scattering/slowing down properties of the hydrogen present in water, critical masses and subcritical limits can be predicted for any water-reflected system at any specified hydrogen-to-actinide atomic ratio knowing only the κ ∞ value of the given fissile solution
National Oceanic and Atmospheric Administration, Department of Commerce — Declination is calculated using the current International Geomagnetic Reference Field (IGRF) model. Declination is calculated using the current World Magnetic Model...
Report to the DOE Nuclear Data Committee, 1983
International Nuclear Information System (INIS)
Haight, R.C.; Struble, G.L.
1983-02-01
Measurements for nuclear data applicactions are described including branching ratio in 7 Be decay, kerma factor for carbon, photoneutron cross sections, neutron differential scattering cross sections, half-life of 77 Kr, stellar neutron capture rates for 86 87 88 Sr, neutron total cross sections, 142 143 144 Nd neutron capture nucleo-synthesis, half-life of 163 Ho, thermal neutron fission of 236 Np, revised branching ratios in 237 U and 238 Pu decays, and levels of 244 Cm populated by the beta decay of 10-hour 244 Am and 26-minute /sup 244m/Am. Calculations discussed include systematic test of microscopic optical models for nucleon scattering in the range 7 to 60 MeV, Lanczos method shell-model calculations of GamowTeller strength functions, explosive nucleosynthesis and direct radiative capture rates, and calculation of fission cross sections. Evaluated data libraries are briefly discussed
Spin-flip isovector giant resonances from the 90Zr (n,p) 90Y reaction at 200 MeV
International Nuclear Information System (INIS)
Raywood, K.J.; Spicer, B.M.
1989-01-01
Doubly differential cross sections of the reaction 90 Zr(n,p) 90 Y have been measured at 200 MeV for excitations up to 38 MeV in the residual nucleus. An overall resolution of 1.3 MeV was achieved. The spectra show qualitative agreement in shape and magnitude with recent RPA calculations; however all of the calculations underestimate the high excitation region of the spectra. A multipole decomposition of the data has been performed using differential cross sections calculated in the DWIA. An estimate of the Gamow-Teller strength in the reaction is given. The isovector spin-flip dipole giant resonance has been identified and there is also an indication of isovector monopole strength. 39 refs., 16 figs., 1 tab
Beta decay and muon capture rates in a self-consistent relativistic framework
Energy Technology Data Exchange (ETDEWEB)
Marketin, Tomislav; Paar, Nils; Niksic, Tamara; Vretenar, Dario [Physics Department, Faculty of Science, University of Zagreb (Croatia); Ring, Peter [Physik-Department, Technische Universitaet Muenchen, D-85748 Muenchen (Germany)
2009-07-01
A fully consistent calculation of muon capture and beta decay rates is presented, based on a microscopic theoretical framework describing the semileptonic weak interaction processes. Nuclear ground state is determined using the Relativistic Hartree-Bogolyubov (RHB) model with density dependent meson-nucleon coupling constants, and transition rates are calculated via proton-neutron relativistic quasiparticle RPA using the same interaction as in the RHB equations. Muon capture rates are calculated for a wide range of nuclei along the valley of stability, from {sup 12}C to {sup 244}Pu, with accuracy of approximately 30%, using the interaction DD-ME2. Previous studies of beta decay rates have only taken into account Gamow-Teller transitions. We extend this approach by including forbidden transitions and systematically study their contribution to decay rates of exotic nuclei along the r-process path, which are important for constraining the conditions in which nucleosynthesis takes place.
International Nuclear Information System (INIS)
Haeusser, O.; Sawafta, R.; Jeppesen, R.G.
1988-01-01
Forward-angle cross sections for 1 + , T = 1 and 1 + , T = 0 states in 28 Si excited by the (p,p') reaction have been measured to determine the energy dependence of important pieces of the effective nucleon-nucleus interaction. The isovector spin-transfer transitions depend on energy as expected from distorted-wave impulse approximation calculations based on the dominant V/sub Σ//sub tau/ part of the Franey-Love interaction. The parts of this interaction responsible for exciting the 9.5 MeV isosca- lar spin-flip transition predict a weaker energy dependence than is observed experimentally. The summed Gamow-Teller strength for isovector transitions below 14.5 MeV is found to be (0.89 +- 0.09) times the result of large-scale shell model calculations
International Nuclear Information System (INIS)
Bengtsson, R.; Krumlinde, J.; Moeller, P.; Nix, J.R.; Zhang, J.
1983-01-01
We study nuclear potential-energy surfaces, ground-state masses and shapes calculated by use of a Yukawa-plus-exponential macroscopic model and a folded-Yukawa single-particle potential for 4023 nuclei ranging from 16 O to 279 112. We discuss extensively the transition from spherical to deformed shapes and study the relation between shape changes and the mass corresponding to the ground-state minimum. The calculated values for the ground-state mass and shape show good agreement with experimental data throughout the periodic system, but some discrepancies remain that deserve further study. We also discuss the effect of deformation on Gamow-Teller #betta#-strength functions
Isovector excitations in charge independent systems
International Nuclear Information System (INIS)
Menezes, D.P.
1986-01-01
A method for building states with good isospin, from states given by the action of an isovector excitation operator on states of the parent multiplet is developed. This new method is a generalization of Toki's method and is applicable to cases involving any isovector excitation operator and a parent state, which is not a double magic nucleus. Once obtained these states with well defined isospin, it is shown how to do a Tamm-Dancoff calculation for determining the energy levels. The transition matrix elements of an isotensor operator are also calculated. An application of this formalism to the Gamow-Teller transition strength in 90 Zr is studied. In this case, besides the double magic configuration, the 2 particles - 2 holes (Π1g 9/2 ) 2 (υ 2p 1/2 -1 ) 2 configuration is also considered. (author) [pt
Charge-exchange QRPA with the Gogny Force for Axially-symmetric Deformed Nuclei
Energy Technology Data Exchange (ETDEWEB)
Martini, M., E-mail: martini.marco@gmail.com [Institut d' Astronomie et d' Astrophysique, Université Libre de Bruxelles, CP-226, 1050 Brussels (Belgium); CEA, DAM, DIF, F-91297 Arpajon (France); Goriely, S. [Institut d' Astronomie et d' Astrophysique, Université Libre de Bruxelles, CP-226, 1050 Brussels (Belgium); Péru, S. [CEA, DAM, DIF, F-91297 Arpajon (France)
2014-06-15
In recent years fully consistent quasiparticle random-phase approximation (QRPA) calculations using finite range Gogny force have been performed to study electromagnetic excitations of several axially-symmetric deformed nuclei up to the {sup 238}U. Here we present the extension of this approach to the charge-exchange nuclear excitations (pnQRPA). In particular we focus on the Isobaric Analog and Gamow-Teller resonances. A comparison of the predicted GT strength distribution with existing experimental data is presented. The role of nuclear deformation is shown. Special attention is paid to β-decay half-lives calculations for which experimental data exist and for specific isotone chains of relevance for the r-process nucleosynthesis.
International Nuclear Information System (INIS)
Sakai, H.; Yako, K.
2009-01-01
The two neutrino double beta (2ν2β) decay proceeds through a sequence of Gamow-Teller (GT) transitions, namely from the parent nucleus to the intermediate nucleus and then from the intermediate nucleus to the final daughter nucleus. The nuclear matrix element M 2ν for the 2ν2β - decay thus consists of the 2β - decay matrix elements for the parent nucleus decay and the 2β - decay matrix elements for the intermediate nucleus decay. These 2β - decay matrix elements can be studied experimentally through the (p, n) reaction for the parent nucleus decay and the (n, p) reaction for the intermediate nucleus decay. The 2ν2β-decay nucleus, 4 8C a is studied. The charge exchange (p, n) and (n, p) measurements at 300 MeV were performed using the neutron time-of-flight facility and the (n,p) facility, respectively, at RCNP. The (p, n) measurement on 4 8C a and the (n,p) measurement on 4 8T i provided us, for the first time, reliable B(GT - ) and B(GT + ) strength distributions up to high excitation energy of 30 MeV of the intermediate nucleus 4 8S c. The multipole decomposition analysis was applied to the angular distributions of the cross section spectra to extract the ΔL = 0 components, which are used to deduce B(GT ± ). Figure shows the double differential cross Nb sections for 4 8C a(p, n)4 8S c (left panel) and 4 8T i(n,p)4 8S c (right panel) reactions. The histograms show the results of the multi-pole decomposition analyses. It is very surprising to find sizable amount of ΔL = 0 yield, i.e. B(GT + ) strength in the highly excited energy region (> 10 MeV). The obtained B(GT ± ) distribution in 4 8S c as well as corresponding nuclear matrix elements M 2ν are compared with theoretical shell model calculation. In this talk, new results will be presented and their implication to the nuclear matrix elements for the 2ν2β-decay will be discussed (author)
Radial plasma drifts deduced from VLF whistler mode signals - A modelling study
Poulter, E. M.; Andrews, M. K.; Bailey, G. J.; Moffett, R. J.
1984-05-01
VLF whistler mode signals have previously been used to infer radial plasma drifts in the equatorial plane of the plasmasphere and the field-aligned ionosphere-protonosphere coupling fluxes. Physical models of the plasmasphere consisting of O(+) adn H(+) ions along dipole magnetic field lines, and including radial E x B drifts, are applied to a mid-latitude flux tube appropriate to whistler mode signals received at Wellington, New Zealand, from the fixed frequency VLF transmitter NLK (18.6 kHz) in Seattle, U.S.A. These models are first shown to provide a good representation of the recorded Doppler shift and group delay data. They are then used to simulate the process of deducing the drifts and fluxes from the recorded data. Provided the initial whistler mode duct latitude and the ionospheric contributions are known, the drifts at the equatorial plane can be estimated to about + or - 20 m/s (approximately 10-15 percent), and the two hemisphere ionosphere-protonosphere coupling fluxes to about + or - 10 to the 12th/sq m-sec (approximately 40 percent).
Geodynamical behavior of some active area in Egypt, as deduced from geodetic and gravity data
Issawy, E.; Mrlina, J.; Radwan, A.; Mahmoud, S.; Rayan, A.
2009-04-01
Temporal gravity variation in parallel with the space geodetic technique (GPS) had been started in Egypt for real campaigns in 1997. The geodetic networks around the High Dam, Aswan area was the first net to be measured. More than five measurement epochs were performed. The results had a considerable limit of coincidence between gravity and GPS observations. The trend of gravity changes indicated a positive stress and had the vertical displacement observed for leveling points. The lowest gravity changes along Kalabsha fault reflect extensional and/or strike component of the stress field. Also, the areas around Cairo (Greater Cairo) and due to the occurrence of an earthquake of 1992, such type of measurements were useful for monitoring the recent activity. The data of the geodetic network around Cairo after 5 campaigns showed that, the estimated horizontal velocities for almost all points are 5.5± mm/year in approximately NW-SE direction. The non-tidal changes can explain the dynamic process within the upper crust related to the development of local stress conditions. The trends of gravity changes are more or less coincident with that deduced from GPS deformation analysis and the occurrence of the main shocks in the area. In additions, in 2005 the geodetic network around the southern part of Sinai and the Gulf of Suez were established. One campaign of measurements had been performed and the gravity values were obtained.
Atmospheric response to Saharan dust deduced from ECMWF reanalysis (ERA) temperature increments
Kishcha, P.; Alpert, P.; Barkan, J.; Kirchner, I.; Machenhauer, B.
2003-09-01
This study focuses on the atmospheric temperature response to dust deduced from a new source of data the European Reanalysis (ERA) increments. These increments are the systematic errors of global climate models, generated in the reanalysis procedure. The model errors result not only from the lack of desert dust but also from a complex combination of many kinds of model errors. Over the Sahara desert the lack of dust radiative effect is believed to be a predominant model defect which should significantly affect the increments. This dust effect was examined by considering correlation between the increments and remotely sensed dust. Comparisons were made between April temporal variations of the ERA analysis increments and the variations of the Total Ozone Mapping Spectrometer aerosol index (AI) between 1979 and 1993. The distinctive structure was identified in the distribution of correlation composed of three nested areas with high positive correlation (>0.5), low correlation and high negative correlation (Forecast (ECMWF) suggest that the PCA (NCA) corresponds mainly to anticyclonic (cyclonic) flow, negative (positive) vorticity and downward (upward) airflow. These findings are associated with the interaction between dust-forced heating/cooling and atmospheric circulation. This paper contributes to a better understanding of dust radiative processes missed in the model.
Epitopes of human testis-specific lactate dehydrogenase deduced from a cDNA sequence
International Nuclear Information System (INIS)
Millan, J.L.; Driscoll, C.E.; LeVan, K.M.; Goldberg, E.
1987-01-01
The sequence and structure of human testis-specific L-lactate dehydrogenase [LDHC 4 , LDHX; (L)-lactate:NAD + oxidoreductase, EC 1.1.1.27] has been derived from analysis of a complementary DNA (cDNA) clone comprising the complete protein coding region of the enzyme. From the deduced amino acid sequence, human LDHC 4 is as different from rodent LDHC 4 (73% homology) as it is from human LDHA 4 (76% homology) and porcine LDHB 4 (68% homology). Subunit homologies are consistent with the conclusion that the LDHC gene arose by at least two independent duplication events. Furthermore, the lower degree of homology between mouse and human LDHC 4 and the appearance of this isozyme late in evolution suggests a higher rate of mutation in the mammalian LDHC genes than in the LDHA and -B genes. Comparison of exposed amino acid residues of discrete anti-genic determinants of mouse and human LDHC 4 reveals significant differences. Knowledge of the human LDHC 4 sequence will help design human-specific peptides useful in the development of a contraceptive vaccine
International Nuclear Information System (INIS)
Dowden, R.L.; Adams, C.D.D.
1989-01-01
Interference between the first two modes of Earth-ionosphere waveguide propagation at the high end of the VLF band (> 18 kHz) increases with distance from the transmitter out to very large distances and can add amplitude perturbations to the phase perturbations (trimpis) produced by lightning-induced electron precipitation (LEP) on the great circle path. Since the two modes have slightly different phase velocities, an interference pattern or standing wave is formed which is shifted slightly along the propagation path by the LEP-induced change in differential phase velocity. The model effect at the receiver depends on the local gradient (along the great circle path) of amplitude with respect to the differential phase. Since this differential or mode beat phase varies with frequency, measurement of the resultant amplitude at two close frequencies enables an estimation of the modal effects. In this study, measurements were made at Dunedin at the two MSK frequencies, 22,250 Hz and 22,350 Hz, of the transmitter NWC, during a night of frequent one-dimensional trimpis (i.e., those produced by large-area LEP occurring close to the great circle path) and of strong and varying modal interference. Modal generation or modification of trimpi amplitude was related to the local gradient of amplitude as expected. From these results it was deduced that modal modification of echo trimpis (those produced by small area LEP occurring well off the great circle path), even under extreme conditions, is insignificant
F-region Pedersen conductivity deduced using the TIMED/GUVI limb retrievals
Directory of Open Access Journals (Sweden)
Y. Zhang
2006-07-01
Full Text Available As a proxy of the Rayleigh-Taylor instability growth rate for equatorial plasma bubbles, we investigate the flux-tube integrated F-region Pedersen conductivity (ΣPF using the electron density profiles (EDPs provided by the Global Ultraviolet Imager (GUVI on board the Thermosphere Ionosphere and Mesosphere Energetics and Dynamics (TIMED satellite. The investigation is conducted using the EDPs obtained in the Atlantic sector at 19:00-22:00 LT during 4–17 August and 6-16 December 2002. The seasonal difference of the strength and location of the equatorial ionization anomalies (EIAs induces a significant difference in the deduced ΣPF. Much stronger EIAs are created at higher altitudes and latitudes in December rather than in August. At 19:00–20:00 LT, the peak value of the ΣPF has 23 mhos at 1100 km apex height during 14–16 December and 18mhos at 600 km during 15–17 August. The ΣPF decreases as local time progresses. Therefore, ΣPF provides a preferred condition for the growth of bubbles to higher altitudes at 19:00-20:00 LT than at later hours, in December rather than in August in the Atlantic sector.
Supercritical fluid in the mantle transition zone deduced from H-D interdiffusion of wadsleyite
Sun, Wei; Yoshino, Takashi; Sakamoto, Naoya; Yurimoto, Hisayoshi
2018-02-01
Knowledge of the distribution of water in the Earth's mantle is key to understanding the mantle convection and geochemical evolution of the Earth. As wadsleyite and ringwoodite can incorporate large amounts of water in their crystal structures, proton conduction has been invoked to account for the widespread conductive anomalies observed in the mantle wedge, where descending slab stagnates at the transition zone. However, there is a lot of controversy on whether proton conduction by itself is able to explain such anomalies, because of large discrepancy in the extent of the water effect deduced from previous electrical conductivity measurements on hydrous polycrystalline wadsleyite and ringwoodite. Here we report the hydrogen self-diffusion coefficient obtained from H-D interdiffusion experiments in wadsleyite single-crystal couples. Our results demonstrate that the effect of water on the electrical conductivity of wadsleyite is limited and hydrous wadsleyite by itself is unable to explain conductive anomalies in the transition zone. In contrast, the expected hydrogen effective diffusion does not allow the wide propagation of water between the stagnant slab and surrounding mantle, probably leading to persistence of local water saturation and continuous release of supercritical fluids at the stagnant slab roof on geological time scales. This phenomenon provides an alternative explanation for both the high-conductivity and seismic-velocity anomalies observed in the mantle wedge at the transition-zone depth.
International Nuclear Information System (INIS)
Scholtyssek, W.
1995-01-01
In the first phase of a benchmark comparison, the CONTAIN code was used to calculate an assumed EPR accident 'medium-sized leak in the cold leg', especially for the first two days after initiation of the accident. The results for global characteristics compare well with those of FIPLOC, MELCOR and WAVCO calculations, if the same materials data are used as input. However, significant differences show up for local quantities such as flows through leakages. (orig.)
A novel computational framework for deducing muscle synergies from experimental joint moments
Directory of Open Access Journals (Sweden)
Anantharaman eGopalakrishnan
2014-12-01
Full Text Available Prior experimental studies have hypothesized the existence of a ‘muscle synergy’ based control scheme for producing limb movements and locomotion in vertebrates. Such synergies have been suggested to consist of fixed muscle grouping schemes with the co-activation of all muscles in a synergy resulting in limb movement. Quantitative representations of these groupings (termed muscle weightings and their control signals (termed synergy controls have traditionally been derived by the factorization of experimentally measured EMG. This study presents a novel approach for deducing these weightings and controls from inverse dynamic joint moments that are computed from an alternative set of experimental measurements – movement kinematics and kinetics. This technique was applied to joint moments for healthy human walking at 0.7 and 1.7 m/s, and two sets of ‘simulated’ synergies were computed based on two different criteria (1 synergies were required to minimize errors between experimental and simulated joint moments in a musculoskeletal model (pure-synergy solution (2 along with minimizing joint moment errors, synergies also minimized muscle activation levels (optimal-synergy solution. On comparing the two solutions, it was observed that the introduction of optimality requirements (optimal-synergy to a control strategy solely aimed at reproducing the joint moments (pure-synergy did not necessitate major changes in the muscle grouping within synergies or the temporal profiles of synergy control signals. Synergies from both the simulated solutions exhibited many similarities to EMG derived synergies from a previously published study, thus implying that the analysis of the two different types of experimental data reveals similar, underlying synergy structures.
Aminzadeh, Milad; Breitenstein, Daniel; Or, Dani
2017-12-01
The intermittent nature of turbulent airflow interacting with the surface is readily observable in fluctuations of the surface temperature resulting from the thermal imprints of eddies sweeping the surface. Rapid infrared thermography has recently been used to quantify characteristics of the near-surface turbulent airflow interacting with the evaporating surfaces. We aim to extend this technique by using single-point rapid infrared measurements to quantify properties of a turbulent flow, including surface exchange processes, with a view towards the development of an infrared surface anemometer. The parameters for the surface-eddy renewal (α and β ) are inferred from infrared measurements of a single-point on the surface of a heat plate placed in a wind tunnel with prescribed wind speeds and constant mean temperatures of the surface. Thermally-deduced parameters are in agreement with values obtained from standard three-dimensional ultrasonic anemometer measurements close to the plate surface (e.g., α = 3 and β = 1/26 (ms)^{-1} for the infrared, and α = 3 and β = 1/19 (ms)^{-1} for the sonic-anemometer measurements). The infrared-based turbulence parameters provide new insights into the role of surface temperature and buoyancy on the inherent characteristics of interacting eddies. The link between the eddy-spectrum shape parameter α and the infrared window size representing the infrared field of view is investigated. The results resemble the effect of the sampling height above the ground in sonic anemometer measurements, which enables the detection of larger eddies with higher values of α . The physical basis and tests of the proposed method support the potential for remote quantification of the near-surface momentum field, as well as scalar-flux measurements in the immediate vicinity of the surface.
Van Dyke, Michael B.
2014-01-01
During random vibration testing of electronic boxes there is often a desire to know the dynamic response of certain internal printed wiring boards (PWBs) for the purpose of monitoring the response of sensitive hardware or for post-test forensic analysis in support of anomaly investigation. Due to restrictions on internally mounted accelerometers for most flight hardware there is usually no means to empirically observe the internal dynamics of the unit, so one must resort to crude and highly uncertain approximations. One common practice is to apply Miles Equation, which does not account for the coupled response of the board in the chassis, resulting in significant over- or under-prediction. This paper explores the application of simple multiple-degree-of-freedom lumped parameter modeling to predict the coupled random vibration response of the PWBs in their fundamental modes of vibration. A simple tool using this approach could be used during or following a random vibration test to interpret vibration test data from a single external chassis measurement to deduce internal board dynamics by means of a rapid correlation analysis. Such a tool might also be useful in early design stages as a supplemental analysis to a more detailed finite element analysis to quickly prototype and analyze the dynamics of various design iterations. After developing the theoretical basis, a lumped parameter modeling approach is applied to an electronic unit for which both external and internal test vibration response measurements are available for direct comparison. Reasonable correlation of the results demonstrates the potential viability of such an approach. Further development of the preliminary approach presented in this paper will involve correlation with detailed finite element models and additional relevant test data.
Hsiao, Yu-Yun; Tsai, Wen-Chieh; Kuoh, Chang-Sheng; Huang, Tian-Hsiang; Wang, Hei-Chia; Wu, Tian-Shung; Leu, Yann-Lii; Chen, Wen-Huei; Chen, Hong-Hwa
2006-07-13
Floral scent is one of the important strategies for ensuring fertilization and for determining seed or fruit set. Research on plant scents has hampered mainly by the invisibility of this character, its dynamic nature, and complex mixtures of components that are present in very small quantities. Most progress in scent research, as in other areas of plant biology, has come from the use of molecular and biochemical techniques. Although volatile components have been identified in several orchid species, the biosynthetic pathways of orchid flower fragrance are far from understood. We investigated how flower fragrance was generated in certain Phalaenopsis orchids by determining the chemical components of the floral scent, identifying floral expressed-sequence-tags (ESTs), and deducing the pathways of floral scent biosynthesis in Phalaneopsis bellina by bioinformatics analysis. The main chemical components in the P. bellina flower were shown by gas chromatography-mass spectrometry to be monoterpenoids, benzenoids and phenylpropanoids. The set of floral scent producing enzymes in the biosynthetic pathway from glyceraldehyde-3-phosphate (G3P) to geraniol and linalool were recognized through data mining of the P. bellina floral EST database (dbEST). Transcripts preferentially expressed in P. bellina were distinguished by comparing the scent floral dbEST to that of a scentless species, P. equestris, and included those encoding lipoxygenase, epimerase, diacylglycerol kinase and geranyl diphosphate synthase. In addition, EST filtering results showed that transcripts encoding signal transduction and Myb transcription factors and methyltransferase, in addition to those for scent biosynthesis, were detected by in silico hybridization of the P. bellina unigene database against those of the scentless species, rice and Arabidopsis. Altogether, we pinpointed 66% of the biosynthetic steps from G3P to geraniol, linalool and their derivatives. This systems biology program combined
Zhou, Yun-Liang; Lühr, Hermann; Alken, Patrick
2018-02-01
Based on 5 years (2001-2005) of magnetic field measurements made by the CHAMP satellite, latitudinal profiles of the equatorial electrojet (EEJ) have been derived. This study provides a comprehensive characterization of the reverse current EEJ sidebands. These westward currents peak at ±5° quasi-dipole latitude with typical amplitudes of 35% of the main EEJ. The diurnal amplitude variation is quite comparable with that of the EEJ. Similarly to the EEJ, the intensity is increasing with solar EUV flux, but with a steeper slope, indicating that not only the conductivity plays a role. For the longitude distribution we find, in general, larger amplitudes in the Western than in the Eastern Hemisphere. It is presently a common understanding that the reverse current EEJ sidebands are generated by eastward zonal winds at altitudes above about 120 km. In particular, a positive vertical gradient of wind speed generates westward currents at magnetic latitudes outside of 2° dip latitude. Interesting information about these features can be deduced from the sidebands' tidal characteristics. The longitudinal variation of the amplitude is dominated by a wave-1 pattern, which can primarily be attributed to the tidal components SPW1 and SW3. In case of the hemispheric amplitude differences these same two wave-1 components dominate. The ratio between sideband amplitude and main EEJ is largely controlled by the tidal features of the EEJ. The longitudinal patterns of the latitude, where the sidebands peak, resemble to some extent those of the amplitude. Current densities become larger when the peaks move closer to the magnetic equator.
De Witte, H; Borzov, I N; Caurier, E; Cederkäll, J; De Smet, A; Eckhaudt, S; Fedorov, D V; Fedosseev, V; Franchoo, S; Górska, M; Grawe, H; Huber, G; Huyse, M; Janas, Z; Köster, U; Kurcewicz, W; Kurpeta, J; Plochocki, A; Van Duppen, P; Van de Vel, K; Weissman, L
2004-01-01
The neutron-rich isotope /sup 218/Bi has been produced in proton- induced spallation of a uranium carbide target at the ISOLDE facility at CERN, extracted from the ion source by the pulsed-release technique and resonant laser ionization, and its beta decay is studied for the first time. A half-life of 33(1)s was measured and is discussed in the self-consistent continuum-quasi particle-random- phase approximation framework that includes Gamow-Teller and first- forbidden transitions. A level scheme was constructed for /sup 218 /Po, and a deexcitation pattern of stretched E2 transitions 8/sup +/ to 6/sup +/ to 4/sup +/ to 2/sup +/ to 0/sup +/ to the ground state is suggested. Shell-model calculations based on the Kuo-Herling interaction reproduce the experimental results satisfactorily. (28 refs).
Gogny interactions with tensor terms
Energy Technology Data Exchange (ETDEWEB)
Anguiano, M.; Lallena, A.M.; Bernard, R.N. [Universidad de Granada, Departamento de Fisica Atomica, Molecular y Nuclear, Granada (Spain); Co' , G. [INFN, Lecce (Italy); De Donno, V. [Universita del Salento, Dipartimento di Matematica e Fisica ' ' E. De Giorgi' ' , Lecce (Italy); Grasso, M. [Universite Paris-Sud, Institut de Physique Nucleaire, IN2P3-CNRS, Orsay (France)
2016-07-15
We present a perturbative approach to include tensor terms in the Gogny interaction. We do not change the values of the usual parameterisations, with the only exception of the spin-orbit term, and we add tensor terms whose only free parameters are the strengths of the interactions. We identify observables sensitive to the presence of the tensor force in Hartree-Fock, Hartree-Fock-Bogoliubov and random phase approximation calculations. We show the need of including two tensor contributions, at least: a pure tensor term and a tensor-isospin term. We show results relevant for the inclusion of the tensor term for single-particle energies, charge-conserving magnetic excitations and Gamow-Teller excitations. (orig.)
Meson exchange currents in nuclei; the triton beta decay as an example
International Nuclear Information System (INIS)
Jaus, W.
1976-01-01
The method used to reduce the four-dimensional Bethe-Salpeter equation to the three-dimensional Schroedinger equation, thus defining a potential in terms of the field theoretic interaction, can be generalized to define a consistent exchange by considering the relativistic interaction of a current with a bound state of nucleons. This covariant approach allows a unified treatment of exchange current effects, renormalization of the nuclear wave function due to meson exchange, relativistic corrections and negative energy contributions to the wave function and it is discussed in detail how these effects influence the Gamow-Teller matrix element for the decay 3 H→ 3 He + e + antiγ. One and two-meson exchange processes are calculated including nucleon resonances in intermediate states, and good agreement of theoretical and experimental predictions for the GT matrix element is found. (Auth.)
Selected aspects in the structure of beta-delayed particle spectra
International Nuclear Information System (INIS)
Honkanen, J.; Aeystoe, J.; Eskola, K.
1986-01-01
Some weak beta-delayed particle emitters in the T z =-3/2, -1, -1/2, +1/2 and +5/2 series are reviewed. Selected features of the delayed particle emission are discussed in terms of experimental delayed particle data and (p,γ), (p,p') and (p,n) reaction data. Experimental beta transition strengths are compared with the existing complete shell-model calculations for the sd-shell nuclei. The effect of the Gamow-Teller giant resonance on the structure of the delayed particle spectra is considered. The correlation between the widths of two decay channels, protons and alpha particles, and the preceeding beta decay is studied in the case of the 40 Sc decay. (orig.)
International Nuclear Information System (INIS)
Onishi, T K; Gelberg, A; Sakurai, H; Yoneda, K; Aoi, N; Imai, N; Baba, H; Brentano, P von; Fukuda, N; Ichikawa, Y; Ishihara, M; Iwasaki, H; Kameda, D; Kishida, T; Lisetskiy, A F; Ong, H J; Osada, M; Otsuka, T; Suzuki, M K; Ue, K; Utsuno, Y; Watanabe, H
2006-01-01
The Gamow-Teller transition of 46 Cr to the N = Z odd-odd nucleus 46 V has been observed for the first time. By means of β-γ coincidence measurements, a γ-ray peak at 993 keV corresponding to the decay of the 1 + 1 state in 46 V was observed. The branching ratio of the decay to this state was found to be b GT = 0.25 ± 0.050. The half-life of 46 Cr was measured to be T 1/2 = 240 ± 140 ms. The transition strength was determined to be B(GT) = 0.64 ± 0.20. This result was compared with theoretical calculations
International Nuclear Information System (INIS)
Paar, N.; Niksic, T.; Marketin, T.; Vretenar, D.; Ring, P.
2005-01-01
The excitation phenomena in unstable nuclei are investigated in the framework of the relativistic quasiparticle random-phase approximation (RQRPA) in the relativistic Hartree-Bogolyubov model (RHB) which is extended to include effective interactions with explicit density-dependent meson-nucleon couplings. The properties of the pygmy dipole resonance (PDR) are examined in 132 Sn and within isotopic chains, showing that already at moderate proton-neutron asymmetry the PDR peak energy is located above the neutron emission threshold. A method is suggested for determining the size of the neutron skin within an isotopic chain, based on the measurement of the excitation energies of the Gamow-Teller resonance relative to the isobaric analog state. In addition, for the first time the relativistic RHB+RQRPA model, with tensor ω meson-nucleon couplings, is employed in calculations of β-decay half-lives of nuclei of the relevance for the r-process. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Paar, N. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); University of Zagreb, Physics Department, Faculty of Science (Croatia); University of Washington, Institute for Nuclear Theory, Seattle (United States); Niksic, T. [University of Zagreb, Physics Department, Faculty of Science (Croatia); University of Washington, Institute for Nuclear Theory, Seattle (United States); Marketin, T.; Vretenar, D. [University of Zagreb, Physics Department, Faculty of Science (Croatia); Ring, P. [Physik-Department der Technischen Universitaet Muenchen, Garching (Germany)
2005-09-01
The excitation phenomena in unstable nuclei are investigated in the framework of the relativistic quasiparticle random-phase approximation (RQRPA) in the relativistic Hartree-Bogolyubov model (RHB) which is extended to include effective interactions with explicit density-dependent meson-nucleon couplings. The properties of the pygmy dipole resonance (PDR) are examined in {sup 132}Sn and within isotopic chains, showing that already at moderate proton-neutron asymmetry the PDR peak energy is located above the neutron emission threshold. A method is suggested for determining the size of the neutron skin within an isotopic chain, based on the measurement of the excitation energies of the Gamow-Teller resonance relative to the isobaric analog state. In addition, for the first time the relativistic RHB+RQRPA model, with tensor {omega} meson-nucleon couplings, is employed in calculations of {beta}-decay half-lives of nuclei of the relevance for the r-process. (orig.)
Uncertainties in modeling low-energy neutrino-induced reactions on iron-group nuclei
International Nuclear Information System (INIS)
Paar, N.; Vretenar, D.; Suzuki, T.; Honma, M.; Marketin, T.
2011-01-01
Charged-current neutrino-nucleus cross sections for 54,56 Fe and 58,60 Ni are calculated and compared using frameworks based on relativistic and Skyrme energy-density functionals and on the shell model. The current theoretical uncertainties in modeling neutrino-nucleus cross sections are assessed in relation to the predicted Gamow-Teller transition strength and available data, to multipole decomposition of the cross sections, and to cross sections averaged over the Michel flux and Fermi-Dirac distribution. By employing different microscopic approaches and models, the decay-at-rest (DAR) neutrino- 56 Fe cross section and its theoretical uncertainty are estimated to be th =(258±57)x10 -42 cm 2 , in very good agreement with the experimental value exp =(256±108±43)x10 -42 cm 2 .
Directory of Open Access Journals (Sweden)
Wu Tian-Shung
2006-07-01
Full Text Available Abstract Background Floral scent is one of the important strategies for ensuring fertilization and for determining seed or fruit set. Research on plant scents has hampered mainly by the invisibility of this character, its dynamic nature, and complex mixtures of components that are present in very small quantities. Most progress in scent research, as in other areas of plant biology, has come from the use of molecular and biochemical techniques. Although volatile components have been identified in several orchid species, the biosynthetic pathways of orchid flower fragrance are far from understood. We investigated how flower fragrance was generated in certain Phalaenopsis orchids by determining the chemical components of the floral scent, identifying floral expressed-sequence-tags (ESTs, and deducing the pathways of floral scent biosynthesis in Phalaneopsis bellina by bioinformatics analysis. Results The main chemical components in the P. bellina flower were shown by gas chromatography-mass spectrometry to be monoterpenoids, benzenoids and phenylpropanoids. The set of floral scent producing enzymes in the biosynthetic pathway from glyceraldehyde-3-phosphate (G3P to geraniol and linalool were recognized through data mining of the P. bellina floral EST database (dbEST. Transcripts preferentially expressed in P. bellina were distinguished by comparing the scent floral dbEST to that of a scentless species, P. equestris, and included those encoding lipoxygenase, epimerase, diacylglycerol kinase and geranyl diphosphate synthase. In addition, EST filtering results showed that transcripts encoding signal transduction and Myb transcription factors and methyltransferase, in addition to those for scent biosynthesis, were detected by in silico hybridization of the P. bellina unigene database against those of the scentless species, rice and Arabidopsis. Altogether, we pinpointed 66% of the biosynthetic steps from G3P to geraniol, linalool and their derivatives
Active deformation processes of the Northern Caucasus deduced from the GPS observations
Milyukov, Vadim; Mironov, Alexey; Rogozhin, Eugeny; Steblov, Grigory; Gabsatarov, Yury
2015-04-01
The Northern Caucasus, as a part of the Alpine-Himalayan mobile belt, is a zone of complex tectonics associated with the interaction of the two major tectonic plates, Arabian and Eurasian. The first GPS study of the contemporary geodynamics of the Caucasus mountain system were launched in the early 1990s in the framework of the Russia-US joint project. Since 2005 observations of the modern tectonic motion of the Northern Caucasus are carried out using the continuous GPS network. This network encompasses the territory of three Northern Caucasian Republics of the Russian Federation: Karachay-Cherkessia, Kabardino-Balkaria, and North Ossetia. In the Ossetian part of the Northern Caucasus the network of GPS survey-mode sites has been deployed as well. The GPS velocities confirm weak general compression of the Northern Caucasus with at the rate of about 1-2 mm/year. This horizontal motion at the boundary of the Northern Caucasus with respect to the Eurasian plate causes the higher seismic and tectonic activity of this transition zone. This result confirms that the source of deformation of the Northern Caucasus is the sub-meridional drift of the Arabian plate towards the adjacent boundary of the Eastern European part of the Eurasian lithospheric plate. The concept of such convergence implies that the Caucasian segment of the Alpine-Himalayan mobile belt is under compression, the layers of sedimentary and volcanic rocks are folded, the basement blocks are subject to shifts in various directions, and the upper crust layers are ruptured by reverse faults and thrusts. Weak deviation of observed velocities from the pattern corresponding to homogeneous compression can also be revealed, and numerical modeling of deformations of major regional tectonic structures, such as the Main Caucasus Ridge, can explain this. The deformation tensor deduced from the velocity field also exhibits the sub-meridional direction of the major compressional axes which coincides with the direction of
International Nuclear Information System (INIS)
Li, D.
1980-01-01
Reviewed is the effect of heat flux of different system parameters on critical density in order to give an initial view on the value of several parameters. A thorough analysis of different equations is carried out to calculate burnout is steam-water flows in uniformly heated tubes, annular, and rectangular channels and rod bundles. Effect of heat flux density distribution and flux twisting on burnout and storage determination according to burnout are commended [ru
Decadal variability in core surface flows deduced from geomagnetic observatory monthly means
DEFF Research Database (Denmark)
Whaler, K. A.; Olsen, Nils; Finlay, Chris
2016-01-01
. On the annual to decadal timescale, the SV is generated primarily by advection in the fluid outer core. We demonstrate the utility of the revised monthly means by calculating models of the core surface advective flow between 1997 and 2013 directly from the SV data. One set of models assumes flow......Monthly means of the magnetic field measurements at ground observatories are a key data source for studying temporal changes of the core magnetic field. However, when they are calculated in the usual way, contributions of external (magnetospheric and ionospheric) origin may remain, which make them...... less favourable for studying the field generated by dynamo action in the core. We remove external field predictions, including a new way of characterising the magnetospheric ring current, from the data and then calculate revised monthly means using robust methods. The geomagnetic secular variation (SV...
Spectroscopy of the doubly magic nucleus {sup 100}Sn and its decay
Energy Technology Data Exchange (ETDEWEB)
Hinke, Christoph B.
2010-07-23
}{sub 0}}=3.29{+-}0.20 MeV. The resultant Gamow-Teller transition strength in the decay of {sup 100}Sn turned out to be a surprisingly high value of B{sub GT}=9.1{sup +4.8}{sub -2.3}. In the daughter nucleus {sup 100}In five gamma rays with transition energies of E{sub {gamma}}=96 keV, 141 keV, 436 keV, 1297 keV and 2048 keV deexciting the populated 1{sup +}-state after the beta decay of {sup 100}Sn could be observed for the first time. Different scenarios for the level structure in {sup 100}In are discussed but can unfortunately not be distinguished on the basis of the present data. For each scenario a ground state to ground state Q{sub EC} value of the decay was calculated. (orig.)
Spectroscopy of the doubly magic nucleus 100Sn and its decay
International Nuclear Information System (INIS)
Hinke, Christoph B.
2010-01-01
The nucleus 100 Sn has been the aim of a number of experimental approaches. It is of great interest for various reasons. It is presumably the heaviest particle-stable N=Z nucleus and at the same time doubly magic. Its beta decay is of particular importance because it is expected to be the purest Gamow-Teller decay in the nuclear chart and thus allows to study the question of the missing Gamow-Teller strength/the Gamow-Teller quenching due to core polarisation effects. From the beta-coincident decay spectroscopy of the daughter nucleus 100 In information about the proton-neutron interaction in this region of the nuclear chart can be obtained. Simultaneously with the implantation of the nucleus in the detector setup after production the search for delayed gamma radiation from a predicted isomeric state in 100 Sn could yield first insight into the structure of excited states in this exotic nucleus. This work presents investigation results concerning the spectroscopy of the doubly magic nucleus 100 Sn and its decay. The experiment was performed in March 2008 at the accelerator facilities of the GSI Helmholtz Zentrum Darmstadt. The neutron deficient nucleus was produced in a projectile fragmentation reaction of a 124 Xe primary beam impinging on a Beryllium target with an energy of 1 GeV x A. After a separation from other fragmentation products and a unique identification 100 Sn was stopped in an implantation detector consisting of highly segmented silicon strip detectors for decay spectroscopy. Beside the determination of the half life it was possible to detect the total energy of the emitted particle radiation in the implantation detector as well as the emitted gamma radiation with a surrounding array of Germanium detectors. With a number of approximately 70 successfully observed decays of 100 Sn a half life of T 1/2 =1.16±0.20s was obtained. The beta endpoint energy of the single channel decay yielded a value of E β 0 =3.29±0.20 MeV. The resultant Gamow-Teller
Structure of the two-neutrino double-β decay matrix elements within perturbation theory
Štefánik, Dušan; Šimkovic, Fedor; Faessler, Amand
2015-06-01
The two-neutrino double-β Gamow-Teller and Fermi transitions are studied within an exactly solvable model, which allows a violation of both spin-isospin SU(4) and isospin SU(2) symmetries, and is expressed with generators of the SO(8) group. It is found that this model reproduces the main features of realistic calculation within the quasiparticle random-phase approximation with isospin symmetry restoration concerning the dependence of the two-neutrino double-β decay matrix elements on isovector and isoscalar particle-particle interactions. By using perturbation theory an explicit dependence of the two-neutrino double-β decay matrix elements on the like-nucleon pairing, particle-particle T =0 and T =1 , and particle-hole proton-neutron interactions is obtained. It is found that double-β decay matrix elements do not depend on the mean field part of Hamiltonian and that they are governed by a weak violation of both SU(2) and SU(4) symmetries by the particle-particle interaction of Hamiltonian. It is pointed out that there is a dominance of two-neutrino double-β decay transition through a single state of intermediate nucleus. The energy position of this state relative to energies of initial and final ground states is given by a combination of strengths of residual interactions. Further, energy-weighted Fermi and Gamow-Teller sum rules connecting Δ Z =2 nuclei are discussed. It is proposed that these sum rules can be used to study the residual interactions of the nuclear Hamiltonian, which are relevant for charge-changing nuclear transitions.
International Nuclear Information System (INIS)
Petersen, K.E.
1986-03-01
Risk and reliability analysis is increasingly being used in evaluations of plant safety and plant reliability. The analysis can be performed either during the design process or during the operation time, with the purpose to improve the safety or the reliability. Due to plant complexity and safety and availability requirements, sophisticated tools, which are flexible and efficient, are needed. Such tools have been developed in the last 20 years and they have to be continuously refined to meet the growing requirements. Two different areas of application were analysed. In structural reliability probabilistic approaches have been introduced in some cases for the calculation of the reliability of structures or components. A new computer program has been developed based upon numerical integration in several variables. In systems reliability Monte Carlo simulation programs are used especially in analysis of very complex systems. In order to increase the applicability of the programs variance reduction techniques can be applied to speed up the calculation process. Variance reduction techniques have been studied and procedures for implementation of importance sampling are suggested. (author)
McCarty, George
1982-01-01
How THIS BOOK DIFFERS This book is about the calculus. What distinguishes it, however, from other books is that it uses the pocket calculator to illustrate the theory. A computation that requires hours of labor when done by hand with tables is quite inappropriate as an example or exercise in a beginning calculus course. But that same computation can become a delicate illustration of the theory when the student does it in seconds on his calculator. t Furthermore, the student's own personal involvement and easy accomplishment give hi~ reassurance and en couragement. The machine is like a microscope, and its magnification is a hundred millionfold. We shall be interested in limits, and no stage of numerical approximation proves anything about the limit. However, the derivative of fex) = 67.SgX, for instance, acquires real meaning when a student first appreciates its values as numbers, as limits of 10 100 1000 t A quick example is 1.1 , 1.01 , 1.001 , •••• Another example is t = 0.1, 0.01, in the functio...
CMB and the elementary particles structure deduced from QFT of non-dot model
Chen, Shao-Guang
In my paper ‘Planck Constant Deduced from Metrical Results of Doppler Effect of Moving Particle —Uncertainty Principle Caused by Collision of a Particle with CMB Photons and Virtual Photons (H05-0036-10)’ the absolute velocity is decided by CMB which as a mark of the vacuum. CMB come from the thermal radiation of stars via gravitational redshift about 10 (13) year (E14- 0032-08). In my paper ‘Quanta turn-advance ism, China Science && Technology Overview 131 192-210 (2011)’, QFT four-dimensional uncertainty principle and momentum-energy conservation law had been generalized as a five-dimensional equations: de Broglie wavelength as a position vector \\underline{q}= (i c t, r, s), momentum \\underline{P} = (i E / c, P, U c), \\underline{q} = i h / \\underline{P}, \\underline{q} \\underline{q} = 0, \\underline{P} \\underline{P} = 0, Sigma∑ \\underline{P} = \\underline{P} (0) . The five-dimensional time-space-spin had been quantized as a non-dot model basic cell, the lowest energy state vertical polarized left spin 1/2 neutrino and right spin 1/2 antineutrino are just the left, right advance unit quanta _{0}nuυ, nuυ _{0} and left, right back unit quanta (0) nuυ, nuυ (0) , it again compose into spin 1 unit advance photons _{0}nuυnuυ _{0} and back (0) nuυnuυ (0) , spin 0 unit rest mass nuυ _{0}nuυ (0) and anti-mass _{0}nuυ (0) nuυ, spin 0 unit positive charge _{0}nuυnuυ (0) and negative charge nuυ _{0} (0) nuυ. It accord to the high energy physics experimental results of the transformation among the photons, masses quanta and charges quanta. The physical vacuum is the even collocation of non-combinational nuυ _{0} or _{0}nuυ. QFT is no longer with divergence difficulty by the non-dot model. It is mathematically easy that from five-dimensional equations deduce out the Dirac, Klein-Gordan, Maxwell equations and Lorentz force formula, but appear some new results. The interactions between _{0}nuυ, nuυ _{0}, (0) nuυ, nuυ (0) , i.e., force f
Fuchs, K.; Tittgemeyer, M.; Ryberg, T.; Wenzel, F.; Mooney, W.
2002-01-01
We infer the fine structure of a sub-Moho boundary layer (SMBL) at the top of the lithospheric mantle from high-resolution seismic observations of Peaceful Nuclear Explosions (PNE) on superlong-range profiles in Russia. Densely recorded seismograms permit recognition of previously unknown features of teleseismic propagation of the well known Pn and Sn phases, such as a band of incoherent, scattered, high-frequency seismic energy, developing consistently from station to station, apparent velocities of sub-Moho material, and high-frequency energy to distances of more than 3000 km with a coda band, incoherent at 10 km spacing and yet consistently observed to the end of the profiles. Estimates of the other key elements of the SMBL were obtained by finite difference calculations of wave propagation in elastic 2D models from a systematic grid search through parameter space. The SMBL consists of randomly distributed, mild velocity fluctuations of 2% or schlieren of high aspect ratios (???40) with long horizontal extent (???20 km) and therefore as thin as 0.5 km only; SMBL thickness is 60-100 km. It is suggested that the SMBL is of global significance as the physical base of the platewide observed high-frequency phases Pn and Sn. It is shown that wave propagation in the SMBL waveguide is insensitive to the background velocity distribution on which its schlieren are superimposed. This explains why the Pn and Sn phases traverse geological provinces of various age, heat flow, crustal thickness, and tectonic regimes. Their propagation appears to be independent of age. temperature, pressure, and stress. Dynamic stretching of mantle material during subduction or flow, possibly combined with chemical differentiation have to be considered as scale-forming processes in the upper mantle. However, it is difficult to distinguish with the present sets of Pn/Sn array data whether (and also where) the boundary layer is a frozen-in feature of paleo-processes or whether it is a response to
DEFF Research Database (Denmark)
Petersen, Kurt Erling
1986-01-01
Risk and reliability analysis is increasingly being used in evaluations of plant safety and plant reliability. The analysis can be performed either during the design process or during the operation time, with the purpose to improve the safety or the reliability. Due to plant complexity and safety...... and availability requirements, sophisticated tools, which are flexible and efficient, are needed. Such tools have been developed in the last 20 years and they have to be continuously refined to meet the growing requirements. Two different areas of application were analysed. In structural reliability probabilistic...... approaches have been introduced in some cases for the calculation of the reliability of structures or components. A new computer program has been developed based upon numerical integration in several variables. In systems reliability Monte Carlo simulation programs are used especially in analysis of very...
Theory for Deducing Volcanic Activity From Size Distributions in Plinian Pyroclastic Fall Deposits
Iriyama, Yu; Toramaru, Atsushi; Yamamoto, Tetsuo
2018-03-01
Stratigraphic variation in the grain size distribution (GSD) of plinian pyroclastic fall deposits reflects volcanic activity. To extract information on volcanic activity from the analyses of deposits, we propose a one-dimensional theory that provides a formula connecting the sediment GSD to the source GSD. As the simplest case, we develop a constant-source model (CS model), in which the source GSD and the source height are constant during the duration of release of particles. We assume power laws of particle radii for the terminal fall velocity and the source GSD. The CS model can describe an overall (i.e., entire vertically variable) feature of the GSD structure of the sediment. It is shown that the GSD structure is characterized by three parameters, that is, the duration of supply of particles to the source scaled by the fall time of the largest particle, ts/tM, and the power indices of the terminal fall velocity p and of the source GSD q. We apply the CS model to samples of the Worzel D ash layer and compare the sediment GSD structure calculated by using the CS model to the observed structure. The results show that the CS model reproduces the overall structure of the observed GSD. We estimate the duration of the eruption and the q value of the source GSD. Furthermore, a careful comparison of the observed and calculated GSDs reveals new interpretation of the original sediment GSD structure of the Worzel D ash layer.
Tardieu, François; Parent, Boris
2017-06-01
Growth under water deficit is controlled by short-term mechanisms but, because of numerous feedbacks, the combination of these mechanisms over time often results in outputs that cannot be deduced from the simple inspection of individual mechanisms. It can be analysed with dynamic models in which causal relationships between variables are considered at each time-step, allowing calculation of outputs that are routed back to inputs for the next time-step and that can change the system itself. We first review physiological mechanisms involved in seven feedbacks of transpiration on plant growth, involving changes in tissue hydraulic conductance, stomatal conductance, plant architecture and underlying factors such as hormones or aquaporins. The combination of these mechanisms over time can result in non-straightforward conclusions as shown by examples of simulation outputs: 'over production of abscisic acid (ABA) can cause a lower concentration of ABA in the xylem sap ', 'decreasing root hydraulic conductance when evaporative demand is maximum can improve plant performance' and 'rapid root growth can decrease yield'. Systems of equations simulating feedbacks over numerous time-steps result in logical and reproducible emergent properties that can be viewed as 'meta-mechanisms' at plant level, which have similar roles as mechanisms at cell level. © 2016 John Wiley & Sons Ltd.
History of Giant Resonances and Quenching
Arima, A
1999-01-01
The history of nuclear magnetic moments and Gamow-Teller transitions is reviewed. The importance of configuration mixing and core polarization to explain the quenching phenomena is shown, and discussed in the context of the recent measurement of the Gamow-Teller strength in sup 9 sup 0 Nb. It is confirmed that the contribution of the DELTA-hole excitation to the quenching of spin matrix elements is small.
Electrodynamics of an omega-band as deduced from optical and magnetometer data
Directory of Open Access Journals (Sweden)
H. Vanhamäki
2009-09-01
Full Text Available We investigate an omega-band event that took place above northern Scandinavia around 02:00–02:30 UT on 9 March 1999. In our analysis we use ground based magnetometer, optical and riometer measurements together with satellite based optical images. The optical and riometer data are used to estimate the ionospheric Hall and Pedersen conductances, while ionospheric equivalent currents are obtained from the magnetometer measurements. These data sets are used as input in a local KRM calculation, which gives the ionospheric potential electric field as output, thus giving us a complete picture of the ionospheric electrodynamic state during the omega-band event. The overall structure of the electric field and field-aligned current (FAC provided by the local KRM method are in good agreement with previous studies. Also the E×B drift velocity calculated from the local KRM solution is in good qualitative agreement with the plasma velocity measured by the Finnish CUTLASS radar, giving further support for the new local KRM method. The high-resolution conductance estimates allow us to discern the detailed structure of the omega-band current system. The highest Hall and Pedersen conductances, ~50 and ~25 S, respectively, are found at the edges of the bright auroral tongue. Inside the tongue, conductances are somewhat smaller, but still significantly higher than typical background values. The electric field shows a converging pattern around the tongues, and the field strength drops from ~40 mV/m found at optically dark regions to ~10 mV/m inside the areas of enhanced conductivity. Downward FAC flow in the dark regions, while upward currents flow inside the auroral tongue. Additionally, sharp conductance gradients at the edge of an auroral tongue are associated with narrow strips of intense FACs, so that a strip of downward current flows at the eastern (leading edge and a similar strip of upward current is present at the western (trailing edge. The Joule
The peculiar acceleration of the Local Group as deduced from the optical and IRAS flux dipoles
International Nuclear Information System (INIS)
Lahav, O.; Lynden-Bell, D.
1988-01-01
The relation between the peculiar acceleration of the Local Group and the surface brightness dipole moments of all-sky optical and IRAS samples is studied. Our revised optical dipole lies within 7 0 of the direction of the Local Group's motion through the Microwave Background Radiation (MBR). The directions of the optical, IRAS and MBR dipoles are all consistent with each other. To analyse the optical dipole we have calculated diameter functions for the UGC and ESO galaxy catalogues from redshift surveys. Most of the optical dipole arises from the Centaurus-Virgo direction and from the 'Local Void' on the opposite side of the sky. The sources of the IRAS dipole are more evenly distributed around the sky. A simple 'shell model', fitted to the variation of the dipoles as a function of flux, suggests that the dipoles arise from galaxies whose recession velocities are smaller than 4000 kms -1 . We find a high Ω 0 value for the IRAS sample and a low one for the optical sample. These results may be reconciled if the optical galaxy distribution is more biased relative to the matter distribution than the IRAS galaxy distribution. (author)
International Nuclear Information System (INIS)
Montbriand, L.E.; Belrose, J.S.
1976-01-01
The occurrence of enhanced ionization after geomagnetic storms, commonly referred to as storm aftereffect, is investigated on the hypothesis that the enhancement is due to a 'drizzle' of energetic electrons from the radiation belts. The study utilized electron density-height profiles obtained from the partial reflection experiment at Ottawa and available information on the height profile of the steady state loss coefficient for energetic electron events in combination with the ion pair production treatments of Ress (1963) and Berger et al. (1974) to deduce two-component differential energy spectra of the electron drizzle. The period studied, December 13--20, 1970, was unique for examining poststorm effects in that the geomagnetic storm on December 14--15 was intense and brief, and it was preceded and followed by periods of geomagnetic calm. The results indicate that the drizzle deduced was minimal before the storm and on the storm day and maximized 2--3 days after the peak of the storm at a time when geomagnetic activity had returned to calm. The results also suggest that the spectrum was hardest shortly after the drizzle maximized. No satisfactory source for the enhanced ionization during the poststorm other than particle drizzle could be found that would produce both the magnitude and the diurnal variation of the effect observed, a conclusion which establishes the validity of the hypothesis made
Foulger, G. R.
1995-04-01
Given a uniform lithology and strain rate and a full seismic data set, the maximum depth of earthquakes may be viewed to a first order as an isotherm. These conditions are approached at the Hengill geothermal area S. Iceland, a dominantly basaltic area. The likely strain rate calculated from thermal and tectonic considerations is 10 -15 s -1, and temperature measurements from four drill sites within the area indicate average, near-surface geothermal gradients of up to 150 °C km -1 throughout the upper 2 km. The temperature at which seismic failure ceases for the strain rates likely at the Hengill geothermal area is determined by analogy with oceanic crust, and is about 650 ± 50 °C. The topographies of the top and bottom of the seismogenic layer were mapped using 617 earthquakes located highly accurately by performing a simultaneous inversion for three-dimensional structure and hypocentral parameters. The thickness of the seismogenic layer is roughly constant and about 3 km. A shallow, aseismic, low-velocity volume within the spreading plate boundary that crosses the area occurs above the top of the seismogenic layer and is interpreted as an isolated body of partial melt. The base of the seismogenic layer has a maximum depth of about 6.5 km beneath the spreading axis and deepens to about 7 km beneath a transform zone in the south of the area. Beneath the high-temperature part of the geothermal area, the maximum depth of earthquakes may be as shallow as 4 km. The geothermal gradient below drilling depths in various parts of the area ranges from 84 ± 9 °Ckm -1 within the low-temperature geothermal area of the transform zone to 138 ± 15 °Ckm -1 below the centre of the high-temperature geothermal area. Shallow maximum depths of earthquakes and therefore high average geothermal gradients tend to correlate with the intensity of the geothermal area and not with the location of the currently active spreading axis.
Emittance calculations for the Stanford Linear Collider injector
International Nuclear Information System (INIS)
Sheppard, J.C.; Clendenin, J.E.; Helm, R.H.; Lee, M.J.; Miller, R.H.; Blocker, C.A.
1983-03-01
A series of measurements have been performed to determine the emittance of the high intensity, single bunch beam that is to be injected into the Stanford Linear Collider. On-line computer programs were used to control the Linac for the purpose of data acquisition and to fit the data to a model in order to deduce the beam emittance. This paper will describe the method of emittance calculation and present some of the measurement results
A constrained variational calculation for beta-stable matter
International Nuclear Information System (INIS)
Howes, C.; Bishop, R.F.; Irvine, J.M
1978-01-01
A method of lowest-order constrained variation previously applied by the authors to asymmetric nuclear matter is extended to include electrons and muons making the nucleon fluid electrically neutral and stable against beta decay. The equilibrium composition of a nucleon fluid is calculated as a function of baryon number density and an equation of state for beta-stable matter is deduced for the Reid soft-core interaction. (author)
Reiner, M. J.; Jackson, B. V.; Webb, D. F.; Mizuno, D. R.; Kaiser, M. L.; Bougeret, J.-L.
2005-09-01
White-light and radio observations are combined to deduce the coronal and interplanetary kinematics of a fast coronal mass ejection (CME) that was ejected from the Sun at about 1700 UT on 2 November 2003. The CME, which was associated with an X8.3 solar flare from W56°, was observed by the Mauna Loa and Solar and Heliospheric Observatory (SOHO) Large-Angle Spectrometric Coronograph (LASCO) coronagraphs to 14 R⊙. The measured plane-of-sky speed of the LASCO CME was 2600 km s-1. To deduce the kinematics of this CME, we use the plane-of-sky white light observations from both the Solar Mass Ejection Imager (SMEI) all-sky camera on board the Coriolis spacecraft and the SOHO/LASCO coronagraph, as well as the frequency drift rate of the low-frequency radio data and the results of the radio direction-finding analysis from the WAVES experiment on the Wind spacecraft. In agreement with the in situ observations for this event, we find that both the white light and radio observations indicate that the CME must have decelerated significantly beginning near the Sun and continuing well into the interplanetary medium. More specifically, by requiring self-consistency of all the available remote and in situ data, together with a simple, but not unreasonable, assumption about the general characteristic of the CME deceleration, we were able to deduce the radial speed and distance time profiles for this CME as it propagated from the Sun to 1 AU. The technique presented here, which is applicable to mutual SMEI/WAVES CME events, is expected to provide a more complete description and better quantitative understanding of how CMEs propagate through interplanetary space, as well as how the radio emissions, generated by propagating CME/shocks, relate to the shock and CME. This understanding can potentially lead to more accurate predictions for the onset times of space weather events, such as those that were observed during this unique period of intense solar activity.
International Nuclear Information System (INIS)
Longworth, J.P.; Tobias, A.
1986-07-01
Work performed at Berkely Nuclear Laboratories both prior to the meeting in Vienna at which USSR gave full details of the Chernobyl accident and after that meeting is recorded. Plume data from Western Europe were used to deduce the likely damage to the fuel and its previous irradiation history. The note concludes that the source to the environment consisted of an initial dispersion of fuel particulate followed by a prolonged release at a lower rate, the total release being some 3% of the core inventory of fuel. Early and late in the release period it was enhanced in volatile species. Damage to the fuel was thus due both to mechanical disruption and to high temperatures. During the early dispersive event high temperatures (probably approaching fuel melting) were reached in some of the core, though the proportion of the fuel affected may have been small. (UK)
International Nuclear Information System (INIS)
Cheverton, R.D.; Canonico, D.A.; Iskander, S.K.; Bolt, S.E.; Holz, P.P.; Nanstad, R.K.; Stelzman, W.J.
1982-01-01
Pressurized water reactors (PWRs) are susceptible to certain types of hypothetical accidents that can subject the reactor pressure vessel to severe thermal shock, that is, a rapid cooling of the inner surface of the vessel wall. The thermal-shock loading, coupled with the radiation-induced reduction in the material fracture toughness, introduces the possibility of propagation of preexistent flaws and what at one time were regarded as somewhat unique fracture-oriented conditions. Several postulated reactor accidents have been analyzed to discover flaw behavior trends; seven intermediate-scale thermal-shock experiments with steel cylinders have been conducted; and corresponding materials characterization studies have been performed. Flaw behavior trends and related fracture-mechanics data deduced from these studies are discussed
McClelland, Arthur; Ahn, Seokhoon; Matzger, Adam J.; Chen, Zhan
2009-03-01
Supplemented by computed models, Scanning Tunneling Microscopy (STM) can provide detailed structure of 2D crystals formed at the liquid/solid interface with atomic resolution. However, some structural information such as functional group orientations in such 2D crystals needs to be tested experimentally to ensure the accuracy of the deduced structures. Due to the limited sensitivity, many other experimental techniques such as Raman and infrared spectroscopy have not been allowed to provide such structural information of 2D crystals. Here we showed that Sum Frequency Generation Vibrational Spectroscopy (SFG) can measure average orientation of functional groups in such 2D crystals, or physisorbed monolayers, providing key experimental data to aid in the modeling and interpretation of the STM images. The usefulness of combining these two techniques is demonstrated with a phthalate diesters monolayer formed at the 1-phenyloctane/ highly oriented pyrolytic graphite (HOPG) interface. The spatial orientation of the ester C=O of the monolayer was successfully determined using SFG.
DEFF Research Database (Denmark)
Tamke, Martin; Myrup Jensen, Morten; Beetz, Jakob
2014-01-01
In recent years, Building Information Models have become commonplace in building profession. The extensive use and increasing experience with BIM models offers new perspectives and potentials for design and planning. A recent stakeholder study conducted by the authors of this paper show that in p......In recent years, Building Information Models have become commonplace in building profession. The extensive use and increasing experience with BIM models offers new perspectives and potentials for design and planning. A recent stakeholder study conducted by the authors of this paper show...... that in practice models are no longer solely observed as culmination of knowledge in a 3d representation of future built structures, but as a source of information in itself. Experienced users of BIM want to Find Information within a model or across a set of these and Compare models in order to evaluate states...... of a model, differences in separate models or models from different point of time. Current BIM tools support both modes only in a rudimentary form. This paper discusses current modes of information query within and across BIM models, shows beneficial scenarios for building and planning practice through...
Inclusion of temperature dependence of fission barriers in statistical model calculations
International Nuclear Information System (INIS)
Newton, J.O.; Popescu, D.G.; Leigh, J.R.
1990-08-01
The temperature dependence of fission barriers has been interpolated from the results of recent theoretical calculations and included in the statistical model code PACE2. It is shown that the inclusion of temperature dependence causes significant changes to the values of the statistical model parameters deduced from fits to experimental data. 21 refs., 2 figs
International Nuclear Information System (INIS)
Hershberger, R.L.; Flynn, D.S.; Gabbard, F.; Johnson, C.H.
1980-01-01
The ( p,p) and ( p,n) cross sections were measured to accuracies of +- 2% and +- 3%, respectively, for 2.0- to 6.7-MeV protons on /sup 107,109/Ag and 115 In. Hauser-Feshbach calculations, which included γ-ray emission channels, were used to convert the ( p,n) cross sections to proton absorption cross sections. Analysis of the ( p,p) and deduced proton absorption cross sections were made simultaneously using a conventional optical-model potential. The measured cross sections can be described using parameters extrapolated from the Sn region in a systematic way, except for a large increase required for the depth of the absorptive potential
Elementary calculation of the shutdown delay of a pile
International Nuclear Information System (INIS)
Yvon, J.
1949-04-01
This study analyzes theoretically the progress of the shutdown of a nuclear pile (reactor) when a cadmium rod is introduced instantaneously. For simplification reasons, the environment of the pile is considered as homogenous and only thermal neutrons are considered (delayed neutrons are neglected). Calculation is made first for a plane configuration (plane vessel, plane multiplier without reflector, and plane multiplier with reflector), and then for a cylindrical configuration (multiplier without reflector, multiplier with infinitely thick reflector, finite cylindrical piles without reflector and with reflector). The self-sustain conditions are calculated for each case and the multiplication length and the shutdown delay are deduced. (J.S.)
Jérôme, Elisabeth; Aubinet, Marc; Heinesch, Bernard
2010-05-01
The general aim of this research is to analyze inter annual variability of carbon dioxide (CO2) fluxes exchanged by a mixed forest located at the Vielsalm experimental site in Belgium. At this site, CO2 flux measurements started in 1996 and are still going on. Thirteen complete years of measurements are thus available. Net Ecosystem Exchange (NEE) inter annual variability may be driven by gross primary productivity (GPP) or Total Ecosystem Respiration (TER), which should thus be both quantified. Using flux partitioning methods, TER is deduced from NEE measurements. GPP is then obtained by subtracting TER from NEE. Initially, a robust estimation of TER is required. This work seeks to compare two independent approaches to assess TER in order to quantify the implications on inter-annual variability. The comparison was performed on twelve complete years. TER estimates can be deduced by extrapolating to the whole day NEE measurements taken during selected night or day periods. In both case, the extrapolation is performed by using a respiration response to temperature. The first approach, referred as the night-time approach, consisted in calculating TER using a temperature response function derived from night-time data sets (Reichstein et al., 2005). The second approach, referred as the daytime approach, consisted in assessing TER from the intercept of the NEE/Photosynthetically Photon Flux Density (PPFD) response (Wohlfahrt et al., 2005). For each approach, different modalities were compared: the use of long term (annual) or short term (15 days) data sets for the night-time approach and the use of different types of regression for the daytime approach. In addition, the impact of the temperature choice was studied for each of the approaches. For the night-time approach, main results showed that air temperature sensitivity of ecosystem respiration derived from annual data did not reflect the short-term air temperature sensitivity. Vielsalm is a summer active ecosystem
An Exact Formula for Calculating Inverse Radial Lens Distortions
Directory of Open Access Journals (Sweden)
Pierre Drap
2016-06-01
Full Text Available This article presents a new approach to calculating the inverse of radial distortions. The method presented here provides a model of reverse radial distortion, currently modeled by a polynomial expression, that proposes another polynomial expression where the new coefficients are a function of the original ones. After describing the state of the art, the proposed method is developed. It is based on a formal calculus involving a power series used to deduce a recursive formula for the new coefficients. We present several implementations of this method and describe the experiments conducted to assess the validity of the new approach. Such an approach, non-iterative, using another polynomial expression, able to be deduced from the first one, can actually be interesting in terms of performance, reuse of existing software, or bridging between different existing software tools that do not consider distortion from the same point of view.
International Nuclear Information System (INIS)
Glasser, S.W.; Korfhagen, T.R.; Weaver, T.E.; Clark, J.C.; Pilot-Matias, T.; Meuth, J.; Fox, J.L.; Whitsett, J.A.
1988-01-01
In hyaline membrane disease of premature infants, lack of surfactant leads to pulmonary atelectasis and respiratory distress. Hydrophobic surfactant proteins of M/sub r/ = 5000-14,000 have been isolated from mammalian surfactants which enhance the rate of spreading and the surface tension lowering properties of phospholipids during dynamic compression. The authors have characterized the amino-terminal amino acid sequence of pulmonary proteolipids from ether/ethanol extracts of bovine, canine, and human surfactant. Two distinct peptides were identified and termed SPL(pVal) and SPL(Phe). An oligonucleotide probe based on the valine-rich amino-terminal amino acid sequence of SPL(pVal) was utilized to isolate cDNA and genomic DNA encoding the human protein, termed surfactant proteolipid SPL(pVal) on the basis of its unique polyvaline domain. The primary structure of a precursor protein of 20,870 daltons, containing the SPL(pVal) peptide, was deduced from the nucleotide sequence of the cDNAs. Hybrid-arrested translation and immunoprecipitation of labeled translation products of human mRNA demonstrated a precursor protein, the active hydrophobic peptide being produced by proteolytic processing. Two classes of cDNAs encoding SPL(pVal) were identified. Human SPL(pVal) mRNA was more abundant in the adult than in fetal lung. The SPL(pVal) gene locus was assigned to chromosome 8
Dougherty, Edward J; Guo, Chunhua; Simons, S Stoney; Chow, Carson C
2012-01-01
Cofactors are intimately involved in steroid-regulated gene expression. Two critical questions are (1) the steps at which cofactors exert their biological activities and (2) the nature of that activity. Here we show that a new mathematical theory of steroid hormone action can be used to deduce the kinetic properties and reaction sequence position for the functioning of any two cofactors relative to a concentration limiting step (CLS) and to each other. The predictions of the theory, which can be applied using graphical methods similar to those of enzyme kinetics, are validated by obtaining internally consistent data for pair-wise analyses of three cofactors (TIF2, sSMRT, and NCoR) in U2OS cells. The analysis of TIF2 and sSMRT actions on GR-induction of an endogenous gene gave results identical to those with an exogenous reporter. Thus new tools to determine previously unobtainable information about the nature and position of cofactor action in any process displaying first-order Hill plot kinetics are now available.
International Nuclear Information System (INIS)
Hummel, K.B.; Litwer, S.; Bradford, A.P.; Aitken, A.; Danner, D.J.; Yeaman, S.J.
1988-01-01
Nucleotide sequence was determined for a 1.6-kilobase human cDNA putative for the branched chain acyltransferase protein of the branched chain α-ketoacid dehydrogenase complex. Translation of the sequence reveals an open reading frame encoding a 315-amino acid protein of molecular weight 35,759 followed by 560 bases of 3'-untranslated sequence. Three repeats of the polyadenylation signal hexamer ATTAAA are present prior to the polyadenylate tail. Within the open reading frame is a 10-amino acid fragment which matches exactly the amino acid sequence around the lipoate-lysine residue in bovine kidney branched chain acyltransferase, thus confirming the identity of the cDNA. Analysis of the deduced protein structure for the human branched chain acyltransferase revealed an organization into domains similar to that reported for the acyltransferase proteins of the pyruvate and α-ketoglutarate dehydrogenase complexes. This similarity in organization suggests that a more detailed analysis of the proteins will be required to explain the individual substrate and multienzyme complex specificity shown by these acyltransferases
Calculation of atomic integrals using commutation relations
International Nuclear Information System (INIS)
Zamastil, J.; Vinette, F.; Simanek, M.
2007-01-01
In this paper, a numerically stable method of calculating atomic integrals is suggested. The commutation relations among the components of the angular momentum and the Runge-Lenz vector are used to deduce recurrence relations for the Sturmian radial functions. The radial part of the one- and two-electron integrals is evaluated by means of these recurrence relations. The product of two radial functions is written as a linear combination of the radial functions. This enables us to write the integrals over four radial functions as a linear combination of the integrals over two radial functions. The recurrence relations for the functions are used to derive the recursion relations for the coefficients of the linear combination and for the integrals over two functions
Qiu, Peiyu; Man, Shuli; Yang, He; Fan, Wei; Yu, Peng; Gao, Wenyuan
2016-08-25
Murine H22 hepatocarcinoma model is so popular to be used for the preclinical anticancer candidate's evaluation. However, the metabolic biomarkers of this model were not identified. Meanwhile, Rhizoma Paridis saponins (RPS) as natural products have been found to show strong antitumor activity, while its anti-cancer mechanism is not clear. To search for potential metabolite biomarkers of this model, serum metabonomics approach was applied to detect the variation of metabolite biomarkers and the related metabolism genes and signaling pathway were used to deduce the antitumor mechanisms of RPS. As a result, ten serum metabolites were identified in twenty-four mice including healthy mice, non-treated cancer mice, RPS-treated cancer mice and RPS-treated healthy mice. RPS significantly decreased tumor weight correlates to down-regulating lactate, acetate, N-acetyl amino acid and glutamine signals (p < 0.05), which were marked metabolites screened according to the very important person (VIP), loading plot and receiver operating characteristic curve (ROC) tests. For the analysis of metabolic enzyme related genes, RPS reversed the aerobic glycolysis through activating tumor suppressor p53 and PTEN, and suppressed FASN to inhibit lipogenesis. What's more, RPS repressed Myc and GLS expression and decreased glutamine level. The regulating PI3K/Akt/mTOR and HIF-1α/Myc/Ras networks also participated in these metabolic changes. Taken together, RPS suppressed ATP product made the tumor growth slow, which indicated a good anti-cancer effect and new angle for understanding the mechanism of RPS. In conclusion, this study demonstrated that the utility of (1)H NMR metabolic profiles taken together with tumor weight and viscera index was a promising screening tool for evaluating the antitumor effect of candidates. In addition, RPS was a potent anticancer agent through inhibiting cancer cellular metabolism to suppress proliferation in hepatoma H22 tumor murine, which promoted the
Directory of Open Access Journals (Sweden)
Kristen Feher
Full Text Available Heterosis, the greater vigor of hybrids compared to their parents, has been exploited in maize breeding for more than 100 years to produce ever better performing elite hybrids of increased yield. Despite extensive research, the underlying mechanisms shaping the extent of heterosis are not well understood, rendering the process of selecting an optimal set of parental lines tedious. This study is based on a dataset consisting of 112 metabolite levels in young roots of four parental maize inbred lines and their corresponding twelve hybrids, along with the roots' biomass as a heterotic trait. Because the parental biomass is a poor predictor for hybrid biomass, we established a model framework to deduce the biomass of the hybrid from metabolite profiles of its parental lines. In the proposed framework, the hybrid metabolite levels are expressed relative to the parental levels by incorporating the standard concept of additivity/dominance, which we name the Combined Relative Level (CRL. Our modeling strategy includes a feature selection step on the parental levels which are demonstrated to be predictive of CRL across many hybrid metabolites. We demonstrate that these selected parental metabolites are further predictive of hybrid biomass. Our approach directly employs the diallel structure in a multivariate fashion, whereby we attempt to not only predict macroscopic phenotype (biomass, but also molecular phenotype (metabolite profiles. Therefore, our study provides the first steps for further investigations of the genetic determinants to metabolism and, ultimately, growth. Finally, our success on the small-scale experiments implies a valid strategy for large-scale experiments, where parental metabolite profiles may be used together with profiles of selected hybrids as a training set to predict biomass of all possible hybrids.
Connor, H. K.; Carter, J. A.
2017-12-01
Soft X-rays can be emitted when highly charged solar wind ions and exospheric neutrals exchange electrons. Astrophysics missions, such as XMM-Newton and ROSAT X-ray telescopes, have found that such solar wind charge exchange happens at the Earth's exosphere. The Earth's magnetosphere can be imaged via soft X-rays in order to understand its interaction with solar wind. Consequently, two soft X-ray telescope missions (CuPID and SMILE) are scheduled to launch in 2019 and 2021. They will provide wide field-of-view soft X-ray images of the Earth's dayside magnetosphere. The imagers will track the location and movement of the cusps, magnetopause, and bow shock in response to solar wind variations. To support these missions, an understanding of exospheric neutral density profile is needed. The neutral density is one of the controlling factors of soft X-ray signals. Strong neutral density can help to obtain high-resolution and high-cadence of soft X-ray images. In this study, we estimate the exospheric neutral density at 10 RE subsolar point using XMM X-ray observations, Cluster plasma observations, and OpenGGCM global magnetosphere - ionosphere MHD model. XMM-Newton observes line-of-sight, narrow field-of-view, integrated soft X-ray emissions when it looks through the dayside magnetosphere. OpenGGCM reproduces soft X-ray signals seen by the XMM spacecraft, assuming exospheric neutral density as a function of the neutral density at the 10RE subsolar point and the radial distance. Cluster observations are used to confirm OpenGGCM plasma results. Finally, we deduce the neutral density at 10 RE subsolar point by adjusting the model results to the XMM-Newton soft X-ray observations.
Itahashi, K.; Oyama, K.; Hayano, R. S.; Gilg, H.; Gillitzer, A.; Knülle, M.; Münch, M.; Schott, W.; Kienle, P.; Geissel, H.; Iwasa, N.; Münzenberg, G.; Hirenzaki, S.; Toki, H.; Yamazaki, T.
2000-08-01
We find a remarkable agreement of the excitation energy spectrum of the 208Pb(d,3He) reaction measured at Td=600 MeV near the π- production threshold with its theoretical prediction. Their comparison leads us to assign the distinct narrow peak observed at about 5 MeV below the threshold to the formation of bound pionic states π-⊗207Pb of the quasisubstitutional configurations (2p)π-(3p3/2,3p1/2)-1n. A small bump observed on the tail of the peak is assigned to the pionic 1s state. The binding energies (Bnl) and the widths (Γnl) of the pionic orbitals are deduced to be B2p=5.13+/-0.02 (stat)+/-0.12 (syst) MeV and Γ2p=0.43+/-0.06 (stat)+/-0.06 (syst) MeV by decomposing the experimental spectrum into the pionic 1s and 2p components. While B2p and Γ2p are determined with small ambiguity, B1s and Γ1s are strongly correlated with each other, and are affected by the relative 1s/2p cross section ratio assumed, since the 1s component is observed only as an unresolved bump. Thus, we have to allow large uncertainties 6.6 MeV
National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Calculator will calculate the total magnetic field, including components (declination, inclination, horizontal intensity, northerly intensity,...
Numerical calculation of radiation pattern of plasma channel antenna
International Nuclear Information System (INIS)
Xia Xinren; Yin Chengyou
2010-01-01
The idea of plasma channel antenna (PCA) for high power microwave weapon is presented in this paper. The radiation pattern of PCA is calculated. The directivity functions of general antenna are derived. The near electromagnetic model of PCA is created based on physical circumstances. The electromagnetic fields of PCA and surrounding air in cylindrical coordinate are given. The dispersion equation of PCA is deduced by applying the boundary conditions of electromagnetic fields. The surface wave vector of PCA is achieved. The variations of radiation characteristic with plasma density, antenna length and antenna radius are emphatically discussed. The controllability of PCA's radiation patterns is confirmed. (authors)
Molecular-Field Calculation of the Magnetic Structure in Erbium
DEFF Research Database (Denmark)
Jensen, J.
1976-01-01
A molecular-field calculation of the magnetic configurations in Er is found to reproduce the neutron diffraction results of the three different magnetic phases and to give a reasonable fit to the magnetization data at 4.2K. The two-ion coupling is considered to be described by the inter......-planar coupling parameters deduced from the dispersion of the spin waves in the low temperature conical phases. The four (effective) crystal-field parameters are determined by the fit to the experimental data. Projecting the magnetic moments present in the intermediate phase of Er (18-52.4K) to a common origin...
Majeed, Raad H.; Oudah, Osamah N.
2018-05-01
Thermonuclear fusion reaction plays an important role in developing and construction any power plant system. Studying the physical behavior for the possible mechanism governed energies released by the fusion products to precise understanding the related kinematics. In this work a theoretical formula controlled the general applied thermonuclear fusion reactions is achieved to calculating the fusion products energy depending upon the reactants physical properties and therefore, one can calculate other parameters governed a given reaction. By using this formula, the energy spectrum of 4He produced from T-3He fusion reaction has been sketched with respect to reaction angle and incident energy ranged from (0.08-0.6) MeV.
International Nuclear Information System (INIS)
Carossi, Jean-Claude
1969-02-01
A CO 2 flowrate calculator has been designed for measuring and recording the gas flow in the loops of Pegase reactor. The analog calculator applies, at every moment, Bernoulli's formula to the values that characterize the carbon dioxide flow through a nozzle. The calculator electronics is described (it includes a sampling calculator and a two-variable function generator), with its amplifiers, triggers, interpolator, multiplier, etc. Calculator operation and setting are presented
Horvath, Monica M.; Rusincovitch, Shelley A.; Brinson, Stephanie; Shang, Howard C.; Evans, Steve; Ferranti, Jeffrey M.
2015-01-01
Purpose Data generated in the care of patients are widely used to support clinical research and quality improvement, which has hastened the development of self-service query tools. User interface design for such tools, execution of query activity, and underlying application architecture have not been widely reported, and existing tools reflect a wide heterogeneity of methods and technical frameworks. We describe the design, application architecture, and use of a self-service model for enterprise data delivery within Duke Medicine. Methods Our query platform, the Duke Enterprise Data Unified Content Explorer (DEDUCE), supports enhanced data exploration, cohort identification, and data extraction from our enterprise data warehouse (EDW) using a series of modular environments that interact with a central keystone module, Cohort Manager (CM). A data-driven application architecture is implemented through three components: an application data dictionary, the concept of “smart dimensions”, and dynamically-generated user interfaces. Results DEDUCE CM allows flexible hierarchies of EDW queries within a grid-like workspace. A cohort “join” functionality allows switching between filters based on criteria occurring within or across patient encounters. To date, 674 users have been trained and activated in DEDUCE, and logon activity shows a steady increase, with variability between months. A comparison of filter conditions and export criteria shows that these activities have different patterns of usage across subject areas. Conclusions Organizations with sophisticated EDWs may find that users benefit from development of advanced query functionality, complimentary to the user interfaces and infrastructure used in other well-published models. Driven by its EDW context, the DEDUCE application architecture was also designed to be responsive to source data and to allow modification through alterations in metadata rather than programming, allowing an agile response to source
Horvath, Monica M; Rusincovitch, Shelley A; Brinson, Stephanie; Shang, Howard C; Evans, Steve; Ferranti, Jeffrey M
2014-12-01
Data generated in the care of patients are widely used to support clinical research and quality improvement, which has hastened the development of self-service query tools. User interface design for such tools, execution of query activity, and underlying application architecture have not been widely reported, and existing tools reflect a wide heterogeneity of methods and technical frameworks. We describe the design, application architecture, and use of a self-service model for enterprise data delivery within Duke Medicine. Our query platform, the Duke Enterprise Data Unified Content Explorer (DEDUCE), supports enhanced data exploration, cohort identification, and data extraction from our enterprise data warehouse (EDW) using a series of modular environments that interact with a central keystone module, Cohort Manager (CM). A data-driven application architecture is implemented through three components: an application data dictionary, the concept of "smart dimensions", and dynamically-generated user interfaces. DEDUCE CM allows flexible hierarchies of EDW queries within a grid-like workspace. A cohort "join" functionality allows switching between filters based on criteria occurring within or across patient encounters. To date, 674 users have been trained and activated in DEDUCE, and logon activity shows a steady increase, with variability between months. A comparison of filter conditions and export criteria shows that these activities have different patterns of usage across subject areas. Organizations with sophisticated EDWs may find that users benefit from development of advanced query functionality, complimentary to the user interfaces and infrastructure used in other well-published models. Driven by its EDW context, the DEDUCE application architecture was also designed to be responsive to source data and to allow modification through alterations in metadata rather than programming, allowing an agile response to source system changes. Copyright © 2014 Elsevier
Schaub, D.; Boersma, K. F.; Kaiser, J. W.; Weiss, A. K.; Folini, D.; Eskes, H. J.; Buchmann, B.
2006-08-01
Nitrogen dioxide (NO2) vertical tropospheric column densities (VTCs) retrieved from the Global Ozone Monitoring Experiment (GOME) are compared to coincident ground-based tropospheric NO2 columns. The ground-based columns are deduced from in situ measurements at different altitudes in the Alps for 1997 to June 2003, yielding a unique long-term comparison of GOME NO2 VTC data retrieved by a collaboration of KNMI (Royal Netherlands Meteorological Institute) and BIRA/IASB (Belgian Institute for Space Aeronomy) with independently derived tropospheric NO2 profiles. A first comparison relates the GOME retrieved tropospheric columns to the tropospheric columns obtained by integrating the ground-based NO2 measurements. For a second comparison, the tropospheric profiles constructed from the ground-based measurements are first multiplied with the averaging kernel (AK) of the GOME retrieval. The second approach makes the comparison independent from the a priori NO2 profile used in the GOME retrieval. This allows splitting the total difference between the column data sets into two contributions: one that is due to differences between the a priori and the ground-based NO2 profile shapes, and another that can be attributed to uncertainties in both the remaining retrieval parameters (such as, e.g., surface albedo or aerosol concentration) and the ground-based in situ NO2 profiles. For anticyclonic clear sky conditions the comparison indicates a good agreement between the columns (n=157, R=0.70/0.74 for the first/second comparison approach, respectively). The mean relative difference (with respect to the ground-based columns) is -7% with a standard deviation of 40% and GOME on average slightly underestimating the ground-based columns. Both data sets show a similar seasonal behaviour with a distinct maximum of spring NO2 VTCs. Further analysis indicates small GOME columns being systematically smaller than the ground-based ones. The influence of different shapes in the a priori and
Directory of Open Access Journals (Sweden)
D. Schaub
2006-01-01
Full Text Available Nitrogen dioxide (NO2 vertical tropospheric column densities (VTCs retrieved from the Global Ozone Monitoring Experiment (GOME are compared to coincident ground-based tropospheric NO2 columns. The ground-based columns are deduced from in situ measurements at different altitudes in the Alps for 1997 to June 2003, yielding a unique long-term comparison of GOME NO2 VTC data retrieved by a collaboration of KNMI (Royal Netherlands Meteorological Institute and BIRA/IASB (Belgian Institute for Space Aeronomy with independently derived tropospheric NO2 profiles. A first comparison relates the GOME retrieved tropospheric columns to the tropospheric columns obtained by integrating the ground-based NO2 measurements. For a second comparison, the tropospheric profiles constructed from the ground-based measurements are first multiplied with the averaging kernel (AK of the GOME retrieval. The second approach makes the comparison independent from the a priori NO2 profile used in the GOME retrieval. This allows splitting the total difference between the column data sets into two contributions: one that is due to differences between the a priori and the ground-based NO2 profile shapes, and another that can be attributed to uncertainties in both the remaining retrieval parameters (such as, e.g., surface albedo or aerosol concentration and the ground-based in situ NO2 profiles. For anticyclonic clear sky conditions the comparison indicates a good agreement between the columns (n=157, R=0.70/0.74 for the first/second comparison approach, respectively. The mean relative difference (with respect to the ground-based columns is −7% with a standard deviation of 40% and GOME on average slightly underestimating the ground-based columns. Both data sets show a similar seasonal behaviour with a distinct maximum of spring NO2 VTCs. Further analysis indicates small GOME columns being systematically smaller than the ground-based ones. The influence of different shapes in the a
Heterogeneous Calculation of {epsilon}
Energy Technology Data Exchange (ETDEWEB)
Jonsson, Alf
1961-02-15
A heterogeneous method of calculating the fast fission factor given by Naudet has been applied to the Carlvik - Pershagen definition of {epsilon}. An exact calculation of the collision probabilities is included in the programme developed for the Ferranti - Mercury computer.
Heterogeneous Calculation of ε
International Nuclear Information System (INIS)
Jonsson, Alf
1961-02-01
A heterogeneous method of calculating the fast fission factor given by Naudet has been applied to the Carlvik - Pershagen definition of ε. An exact calculation of the collision probabilities is included in the programme developed for the Ferranti - Mercury computer
Nuclear structure and weak rates of heavy waiting point nuclei under rp-process conditions
Nabi, Jameel-Un; Böyükata, Mahmut
2017-01-01
The structure and the weak interaction mediated rates of the heavy waiting point (WP) nuclei 80Zr, 84Mo, 88Ru, 92Pd and 96Cd along N = Z line were studied within the interacting boson model-1 (IBM-1) and the proton-neutron quasi-particle random phase approximation (pn-QRPA). The energy levels of the N = Z WP nuclei were calculated by fitting the essential parameters of IBM-1 Hamiltonian and their geometric shapes were predicted by plotting potential energy surfaces (PESs). Half-lives, continuum electron capture rates, positron decay rates, electron capture cross sections of WP nuclei, energy rates of β-delayed protons and their emission probabilities were later calculated using the pn-QRPA. The calculated Gamow-Teller strength distributions were compared with previous calculation. We present positron decay and continuum electron capture rates on these WP nuclei under rp-process conditions using the same model. For the rp-process conditions, the calculated total weak rates are twice the Skyrme HF+BCS+QRPA rates for 80Zr. For remaining nuclei the two calculations compare well. The electron capture rates are significant and compete well with the corresponding positron decay rates under rp-process conditions. The finding of the present study supports that electron capture rates form an integral part of the weak rates under rp-process conditions and has an important role for the nuclear model calculations.
Calculation of neutron background for underground experiments
Energy Technology Data Exchange (ETDEWEB)
Tomasello, V. [Department of Physics and Astronomy, University of Sheffield, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Physikalisches Institut, Eberhard Karls Universitaet Tuebingen, Auf der Morgenstelle 14, Tuebingen D-72076 (Germany)], E-mail: v.tomasello@sheffield.ac.uk; Kudryavtsev, V.A.; Robinson, M. [Department of Physics and Astronomy, University of Sheffield, Hounsfield Road, Sheffield S3 7RH (United Kingdom)
2008-10-01
New generation dark matter experiments aim at exploring the 10{sup -9}-10{sup -10}pb cross-section region for the WIMP-nucleon scalar interactions. Neutrons produced in the detector components are one of the main factors that can limit detector sensitivity. Estimation of the background from this source then becomes a crucial task for designing future large-scale detectors. Energy spectra and production rates for neutrons coming from radioactive contamination are required for all materials in and around the detector. In order to estimate neutron yields and spectra, the cross-sections of ({alpha},n) reactions and probabilities of transitions to different excited states should be known. Cross-sections and transition probabilities have been calculated using EMPIRE2.19 for several isotopes, and for some isotopes, a comparison with the experimental data is shown. The results have been used to calculate the neutron spectra from materials using the code SOURCES4A. Neutron background event rates from some detector components in a hypothetical dark matter detector based on Ge crystals have been estimated. Some requirements for the radiopurity of the materials have been deduced from the results of these simulations.
Calculation of neutron background for underground experiments
International Nuclear Information System (INIS)
Tomasello, V.; Kudryavtsev, V.A.; Robinson, M.
2008-01-01
New generation dark matter experiments aim at exploring the 10 -9 -10 -10 pb cross-section region for the WIMP-nucleon scalar interactions. Neutrons produced in the detector components are one of the main factors that can limit detector sensitivity. Estimation of the background from this source then becomes a crucial task for designing future large-scale detectors. Energy spectra and production rates for neutrons coming from radioactive contamination are required for all materials in and around the detector. In order to estimate neutron yields and spectra, the cross-sections of (α,n) reactions and probabilities of transitions to different excited states should be known. Cross-sections and transition probabilities have been calculated using EMPIRE2.19 for several isotopes, and for some isotopes, a comparison with the experimental data is shown. The results have been used to calculate the neutron spectra from materials using the code SOURCES4A. Neutron background event rates from some detector components in a hypothetical dark matter detector based on Ge crystals have been estimated. Some requirements for the radiopurity of the materials have been deduced from the results of these simulations
Experimental study of radiative pion capture on 13C, 20Ne, 90Zr, 19F and 12C
International Nuclear Information System (INIS)
Martoff, C.J.
1980-11-01
Photon spectra for 50 13 C, 19 F, 20 Ne, and 90 Zr. The e + e - pair spectrometer system used has resolution 850 keV fwhm and photon detection efficiency 5 x 10 -6 . The total radiative capture branching ratios measured are 13 C (1.66 +- 0.25)%, 19 F (2.40 +- 0.48)%, 20 Ne (1.60 +- 0.24)%, and 90 Zr (2.1 +- 0.5)%. The partial radiative capture branching ratios to four bound states and two resonances in 20 F, and two bound states and three resonances in 13 B have also been measured. The branching ratio for 13 C(π - ,γ) 13 B g.s. is (6.1 +- 1.2) x 10 -4 . Comparison of this result with the beta decay rate of 13 B shows that (84 +- 16)% of the pion capture amplitude is accounted for by the Gamow-Teller matrix element. Further analysis suggests that much of the remaining strength is E2. The measured branching ratios to resonant states in 13 C(π - ,γ) 13 B are shown to be in agreement with detailed shell model calculations. The total single-particle strength in these transitions is shown to be approximately half as large as that of the T = 3/2 part of the E1 photoresonance (the Giant Dipole Resonance) in 13 C. The branching ratio for 20 Ne(π - ,γ) 20 F (T = 1, J/sup π/ = 1 + , E/sub x/ = 1.06 MeV) is 0.91 +- 0.52).10 -4 . Comparison with the electroexcitation of the analog giant M1 state in 20 Ne (11.24 MeV) shows that the M1 transition amplitude is less than (46 +- 14)% Gamow-Teller. This result is in agreement with detailed shell model calculations of the M1 transition. The photon spectrum for radiative pion capture from flight (reaction 12 C(π + T = 44 MeV, γ at 90 0 )) has been measured. 13 figures, 12 tables
Energy Technology Data Exchange (ETDEWEB)
Nagao, Yoshiharu [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment
1998-03-01
In material testing reactors like the JMTR (Japan Material Testing Reactor) of 50 MW in Japan Atomic Energy Research Institute, the neutron flux and neutron energy spectra of irradiated samples show complex distributions. It is necessary to assess the neutron flux and neutron energy spectra of an irradiation field by carrying out the nuclear calculation of the core for every operation cycle. In order to advance core calculation, in the JMTR, the application of MCNP to the assessment of core reactivity and neutron flux and spectra has been investigated. In this study, in order to reduce the time for calculation and variance, the comparison of the results of the calculations by the use of K code and fixed source and the use of Weight Window were investigated. As to the calculation method, the modeling of the total JMTR core, the conditions for calculation and the adopted variance reduction technique are explained. The results of calculation are shown. Significant difference was not observed in the results of neutron flux calculations according to the difference of the modeling of fuel region in the calculations by K code and fixed source. The method of assessing the results of neutron flux calculation is described. (K.I.)
Discrepancies between calculated and observed Fe XVII and Ni XIX solar coronal lines
Energy Technology Data Exchange (ETDEWEB)
Loulergue, M [Observatoire de Paris, Section de Meudon, 92 (France); Nussbaumer, H [Eidgenoessische Technische Hochschule, Zurich (Switzerland)
1975-12-01
The 36-levels model atom Fe/sup +16/ of Loulergue and Nussbaumer (1973) is extended to a 51-levels atom including n=4 configuration. The earlier conclusion that relative intensities among the Fe XVII lines are not sufficiently sensitive to variations in electron densities and electron temperature to deduce these parameters from observed intensity ratios still holds. Discrepancies between calculated and observed relative intensities in Fe XVII and Ni XIX are attributed to blends or misidentifications.
International Nuclear Information System (INIS)
Carneiro, L.B.; Dourado, M.A.; Barbosa, R.C.
2017-01-01
To reassess the calculations of the effective dose equivalent to obtain data of dosimetry and the accomplishment of the analysis comparing the data of several techniques that record doses of radiation originating from the cosmogenic and terrestrial contributions that make up the so-called background radiation. the basic information to be obtained is the contribution of the difference between the terrestrial dose equivalents, even the lowest concentration of primordial radionuclides, and that of the dose equivalent, deduced from TLD readings. (author)
Energy Technology Data Exchange (ETDEWEB)
Carneiro, L.B.; Dourado, M.A.; Barbosa, R.C., E-mail: research.photonics@gmail.com [Centro Regional de Ciências Nucleares do Centro-Oeste (CRCN-CO/CNEN-GO), Abadia de Goiás, GO (Brazil)
2017-07-01
To reassess the calculations of the effective dose equivalent to obtain data of dosimetry and the accomplishment of the analysis comparing the data of several techniques that record doses of radiation originating from the cosmogenic and terrestrial contributions that make up the so-called background radiation. the basic information to be obtained is the contribution of the difference between the terrestrial dose equivalents, even the lowest concentration of primordial radionuclides, and that of the dose equivalent, deduced from TLD readings. (author)
Optical and statistical model calculation of the americium 242m capture cross section
International Nuclear Information System (INIS)
Tellier, Henry.
1981-04-01
The capture cross sections of Am 242m can be deduced from resonances analysis at low energy and computed with theoretical models at high energy. In this work, a coherent set of cross sections which reproduced the experimental values of the fission cross sections is computed. These calculations were performed for an energy of the incoming neutron between 1 keV and 1 MeV
Energy Technology Data Exchange (ETDEWEB)
Lemke, H.M. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Atmosphaerenphysik
2000-07-01
The potential of polarimetric radar measurements at 95 GHz to derive microphysical cloud characteristics is assessed. Scattering by atmospheric ice crystals is calculated applying the discrete dipole approximation (DDA) for single crystals of various shape, size, and orientation. The results are combined to acquire radar signals for collections of particles representing the radar volume. Expressing the particle size with respect to the radius of a volume equivalent sphere, the co-plar reflectivity is only slightly affected by particle shape variations. Thus, keeping the limitations of such an approach in mind, the simplified representation of crystals as spheres is applicable. On the other hand, the signal is strongly influenced by the particle size and the total ice water content. Polarimetric radar parameters like linear depolarisation ratio and differential reflectivity are almost independent of size and ice water content. They are predominantly affected by the crystal shape and orientation and therefore have a potential to deduce information about ice crystal habits. Unfortunately, to date such measurements are subject to technical restrictions. (orig.)
Amelia, Kassim; Khor, Chin Yin; Shah, Farida Habib; Bhore, Subhash J
2015-01-01
Common beans (Phaseolus vulgaris L.) are widely consumed as a source of proteins and natural products. However, its yield needs to be increased. In line with the agenda of Phaseomics (an international consortium), work of expressed sequence tags (ESTs) generation from bean pods was initiated. Altogether, 5972 ESTs have been isolated. Alcohol dehydrogenase (AD) encoding gene cDNA was a noticeable transcript among the generated ESTs. This AD is an important enzyme; therefore, to understand more about it this study was undertaken. The objective of this study was to elucidate P. vulgaris L. AD (PvAD) gene cDNA sequence and to predict the three-dimensional (3D) structure of deduced protein. positive and negative strands of the PvAD cDNA clone were sequenced using M13 forward and M13 reverse primers to elucidate the nucleotide sequence. Deduced PvAD cDNA and protein sequence was analyzed for their basic features using online bioinformatics tools. Sequence comparison was carried out using bl2seq program, and tree-view program was used to construct a phylogenetic tree. The secondary structures and 3D structure of PvAD protein were predicted by using the PHYRE automatic fold recognition server. The sequencing results analysis showed that PvAD cDNA is 1294 bp in length. It's open reading frame encodes for a protein that contains 371 amino acids. Deduced protein sequence analysis showed the presence of putative substrate binding, catalytic Zn binding, and NAD binding sites. Results indicate that the predicted 3D structure of PvAD protein is analogous to the experimentally determined crystal structure of s-nitrosoglutathione reductase from an Arabidopsis species. The 1294 bp long PvAD cDNA encodes for 371 amino acid long protein that contains conserved domains required for biological functions of AD. The predicted deduced PvAD protein's 3D structure reflects the analogy with the crystal structure of Arabidopsis thaliana s-nitrosoglutathione reductase. Further study is required
Electronics Environmental Benefits Calculator
U.S. Environmental Protection Agency — The Electronics Environmental Benefits Calculator (EEBC) was developed to assist organizations in estimating the environmental benefits of greening their purchase,...
Electrical installation calculations basic
Kitcher, Christopher
2013-01-01
All the essential calculations required for basic electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practice. A step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3Fo
Electrical installation calculations advanced
Kitcher, Christopher
2013-01-01
All the essential calculations required for advanced electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practiceA step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3For apprentices and electrical installatio
Radar Signature Calculation Facility
Federal Laboratory Consortium — FUNCTION: The calculation, analysis, and visualization of the spatially extended radar signatures of complex objects such as ships in a sea multipath environment and...
Waste Package Lifting Calculation
International Nuclear Information System (INIS)
H. Marr
2000-01-01
The objective of this calculation is to evaluate the structural response of the waste package during the horizontal and vertical lifting operations in order to support the waste package lifting feature design. The scope of this calculation includes the evaluation of the 21 PWR UCF (pressurized water reactor uncanistered fuel) waste package, naval waste package, 5 DHLW/DOE SNF (defense high-level waste/Department of Energy spent nuclear fuel)--short waste package, and 44 BWR (boiling water reactor) UCF waste package. Procedure AP-3.12Q, Revision 0, ICN 0, calculations, is used to develop and document this calculation
Energy Technology Data Exchange (ETDEWEB)
Yvon, J
1949-04-01
This study analyzes theoretically the progress of the shutdown of a nuclear pile (reactor) when a cadmium rod is introduced instantaneously. For simplification reasons, the environment of the pile is considered as homogenous and only thermal neutrons are considered (delayed neutrons are neglected). Calculation is made first for a plane configuration (plane vessel, plane multiplier without reflector, and plane multiplier with reflector), and then for a cylindrical configuration (multiplier without reflector, multiplier with infinitely thick reflector, finite cylindrical piles without reflector and with reflector). The self-sustain conditions are calculated for each case and the multiplication length and the shutdown delay are deduced. (J.S.)
Nucleon charge-exchange reactions at intermediate energy
International Nuclear Information System (INIS)
Alford, W.P.; Spicer, B.M.
1997-01-01
An historical review of the development of ideas pertaining to Gamow-Teller giant resonances is given, and a description of the emergence of techniques for the study of charge exchange reactions - particularly the technical advances which yielded the recent volume of new date. The present status of charge exchange reactions is reviewed and assessed. Evidence is presented from the 14 C(p,n) reaction for the dominance of the spin-isospin component of the nucleon-nucleon interaction in intermediate energy reactions. In (p,n) reactions the Gamow-Teller giant resonance dominates the spectra, with higher multipoles contributing. By contrast, in (n,p) reactions in the heavier nuclei, the Gamow-Teller transitions are substantially Pauli-blocked and the spin dipole resonance dominates, with contributions from higher multipoles. Discussions of the multipole decomposition process, used to obtain from the data the contributions of the different multipoles, and the contributions of the multipoles, are given
Nucleus as a chiral filter: the role of the Δ(1232)
International Nuclear Information System (INIS)
Rho, Mannque.
1982-03-01
We describe how two different modes of chiral symmetry can be seen in nuclei. In particular, it is shown that the nuclear axial charge or more precisely the O + O - , ΔT=1 transition at zero momentum transfer probe the nuclear configuration wherein the axial charge gsub(A) is effectively enhanced in nuclear medium due to soft pions, symptomatic of the Goldstone realization of chiral symmetry in the medium while the Gamow-Teller resonances probe the configuration wherein soft pions are no longer operative, suggesting an approach toward the Wigner realization of chiral symmetry. Using the celebrated Adler-Weisberger relation, it is argued that the observed approximately 50% quenching of the Gamow-Teller strength reflects the possibility that the Gamow-Teller operator sees the quarks inside the bag, blind to the Goldstone vacuum outside. Some implications on chiral phase transitions are also discussed
Diffusion theory model for optimization calculations of cold neutron sources
International Nuclear Information System (INIS)
Azmy, Y.Y.
1987-01-01
Cold neutron sources are becoming increasingly important and common experimental facilities made available at many research reactors around the world due to the high utility of cold neutrons in scattering experiments. The authors describe a simple two-group diffusion model of an infinite slab LD 2 cold source. The simplicity of the model permits to obtain an analytical solution from which one can deduce the reason for the optimum thickness based solely on diffusion-type phenomena. Also, a second more sophisticated model is described and the results compared to a deterministic transport calculation. The good (particularly qualitative) agreement between the results suggests that diffusion theory methods can be used in parametric and optimization studies to avoid the generally more expensive transport calculations
International Nuclear Information System (INIS)
Trkov, A.; Ravnik, M.; Zeleznik, N.
1992-01-01
Functional description of the programme package Cord-2 for PWR core design calculations is presented. Programme package is briefly described. Use of the package and calculational procedures for typical core design problems are treated. Comparison of main results with experimental values is presented as part of the verification process. (author) [sl
Uneconomical top calculation method
International Nuclear Information System (INIS)
De Noord, M.; Vanm Sambeek, E.J.W.
2003-08-01
The methodology used to calculate the financial gap of renewable electricity sources and technologies is described. This methodology is used for calculating the production subsidy levels (MEP subsidies) for new renewable electricity projects in 2004 and 2005 in the Netherlands [nl
International Nuclear Information System (INIS)
Ahn, T.G.; Cohn, D.V.; Gorr, S.U.; Ornstein, D.L.; Kashdan, M.A.; Levine, M.A.
1987-01-01
Secretory protein I (SP-I), also referred to as chromogranin A, is an acidic glycoprotein that has been found in every tissue of endocrine and neuroendocrine origin examined but never in exocrine or epithelial cells. Its co-storage and co-secretion with peptide hormones and neurotransmitters suggest that it has an important endocrine or secretory function. The authors have isolated cDNA clones from a bovine pituitary λgt11 expression library using an antiserum to parathyroid SP-I. The largest clone (SP4B) hybridized to a transcript of 2.1 kilobases in RNA from parathyroid, pituitary, and adrenal medulla. Immunoblots of bacterial lysates derived from SP4B lysognes demonstrated specific antibody binding to an SP4B/β-galactosidase fusion protein (160 kDa) with a cDNA-derived component of 46 kDa. Radioimmunoassay of the bacterial lystates with SP-I antiserum yielded parallel displacement curves of 125 I-labeled SP-I by the SP4B lysate and authentic SP-I. SP4B contains a cDNA of 1614 nucleotides that encodes a 449-amino acid protein (calculated mass, 50 kDa). The nucleotide sequences of the pituitary SP-I cDNA and adrenal medullary SP-I cDNAs are nearly identical. Analysis of genomic DNA suggests that pituitary, adrenal, and parathyroid SP-I are products of the same gene
Directory of Open Access Journals (Sweden)
H. Veit
2007-10-01
Full Text Available Surface exposure dating (SED is an innovative tool already being widely applied for moraine dating and for Late Quaternary glacier and climate reconstruction. Here we present exposure ages of 28 boulders from the Cordillera Real and the Cordillera Cochabamba, Bolivia. Our results indicate that the local Last Glacial Maximum (LGM in the Eastern Cordilleras occurred at ~22–25 ka and was thus synchronous to the global temperature minimum. We were also able to date several Late Glacial moraines to ~11–13 ka, which likely document lower temperatures and increased precipitation ("Coipasa" humid phase. Additionally, we recognize the existence of older Late Glacial moraines re-calculated to ~15 ka from published cosmogenic nuclide data. Those may coincide with the cold Heinrich 1 event in the North Atlantic region and the pronounced "Tauca" humid phase. We conclude that (i exposure ages in the tropical Andes may have been overestimated so far due to methodological uncertainties, and (ii although precipitation plays an important role for glacier mass balances in the tropical Andes, it becomes the dominant forcing for glaciation only in the drier and thus more precipitation-sensitive regions farther west and south.
Moro, M. V.; Bruckner, B.; Grande, P. L.; Tabacniks, M. H.; Bauer, P.; Primetzhofer, D.
2018-06-01
We have experimentally determined electronic stopping cross sections of vanadium for 50-2750 keV protons and for 250-6000 keV He ions by relative measurements in backscattering geometry. To check the consistency of the employed procedure we investigate how to define adequate reference stopping cross section data and chose different reference materials. To proof consistency of different reference data sets, an intercomparison is performed to test the reliability of the evaluation procedure for a wide range of energies. This process yielded consistent results. The resulting stopping cross section data for V are compared to values from the IAEA database, to the most commonly employed semi-empirical program SRIM, and to calculations according to CasP. For helium, our results show a significant deviation of up to 10% with respect to literature and to SRIM, but are in very good agreement with the CasP predictions, in particular when charge-exchange processes are included in the model.
Cohen, Barbara A.; Coker, R. F.
2009-01-01
The South Pole-Aitken (SPA) basin is an important target for absolute age-dating. Vertical and lateral impact mixing ensures that regolith within SPA will contain rock fragments from SPA itself, local impact craters, and faraway giant basins. About 20% of the regolith at any given site is foreign [1, 2], but much of this material will be cold ejecta, not impact melt. We calculated the fraction of contributed impact melt using scaling laws to estimate the amount and provenance of impact melt, demonstrating that SPA melt is the dominant impact melt rock (>70%) likely to be present. We also constructed a statistical model to illustrate how many randomly-selected impact-melt fragments would need to be dated, and with what accuracy, to confidently reproduce the impact history of a site. A detailed impact history becomes recognizable after a few hundred to a thousand randomly-selected marbles, however, it will be useful to have more information (e.g. compositional, mineralogical, remote sensing) to group fragments. These exercises show that SPA melt has a high probability of being present in a scoop sample and that dating of a few hundred to a thousand impact-melt fragments will yield the impact history of the SPA basin.
Energy Technology Data Exchange (ETDEWEB)
Ahn, T.G.; Cohn, D.V.; Gorr, S.U.; Ornstein, D.L.; Kashdan, M.A.; Levine, M.A.
1987-07-01
Secretory protein I (SP-I), also referred to as chromogranin A, is an acidic glycoprotein that has been found in every tissue of endocrine and neuroendocrine origin examined but never in exocrine or epithelial cells. Its co-storage and co-secretion with peptide hormones and neurotransmitters suggest that it has an important endocrine or secretory function. The authors have isolated cDNA clones from a bovine pituitary lambdagt11 expression library using an antiserum to parathyroid SP-I. The largest clone (SP4B) hybridized to a transcript of 2.1 kilobases in RNA from parathyroid, pituitary, and adrenal medulla. Immunoblots of bacterial lysates derived from SP4B lysognes demonstrated specific antibody binding to an SP4B/..beta..-galactosidase fusion protein (160 kDa) with a cDNA-derived component of 46 kDa. Radioimmunoassay of the bacterial lystates with SP-I antiserum yielded parallel displacement curves of /sup 125/I-labeled SP-I by the SP4B lysate and authentic SP-I. SP4B contains a cDNA of 1614 nucleotides that encodes a 449-amino acid protein (calculated mass, 50 kDa). The nucleotide sequences of the pituitary SP-I cDNA and adrenal medullary SP-I cDNAs are nearly identical. Analysis of genomic DNA suggests that pituitary, adrenal, and parathyroid SP-I are products of the same gene.
Directory of Open Access Journals (Sweden)
Kunio Kawamura
2016-08-01
Full Text Available RNA played a central role in the emergence of the first life-like system on primitive Earth since RNA molecules contain both genetic information and catalytic activity. However, there are several drawbacks regarding the RNA world hypothesis. Here, I briefly discuss the feasibility of the RNA world hypothesis to deduce the RNA functions that are essential for forming a life-like system. At the same time, I have conducted a conceptual analysis of the characteristics of biosystems as a useful approach to deduce a realistic life-like system in relation to the definition of life. For instance, an RNA-based life-like system should possess enough stability to resist environmental perturbations, by developing a cell-like compartment, for instance. Here, a conceptual viewpoint is summarized to provide a realistic life-like system that is compatible with the primitive Earth environment and the capabilities of RNA molecules. According to the empirical and conceptual analysis, I propose the hypothesis that the first life-like system could have initiated from only two genes.
International Nuclear Information System (INIS)
Kawamura, Kenji; Nakazawa, Takakiyo; Aoki, Shuji
2003-01-01
A deep ice core drilled at Dome Fuji, East Antarctica was analyzed for the CO 2 concentration using a wet extraction method in order to reconstruct its atmospheric variations over the past 320 kyr, which includes three full glacial-interglacial climatic cycles, with a mean time resolution of about 1.1 kyr. The CO 2 concentration values derived for the past 65 kyr are very close to those obtained from other Antarctic ice cores using dry extraction methods, although the wet extraction method is generally thought to be inappropriate for the determination of the CO 2 concentration. The comparison between the CO 2 and Ca 2+ concentrations deduced from the Dome Fuji core suggests that calcium carbonate emitted from lands was mostly neutralized in the atmosphere before reaching the central part of Antarctica, or that only a small part of calcium carbonate was involved in CO 2 production during the wet extraction process. The CO 2 concentration for the past 320 kyr deduced from the Dome Fuji core varies between 190 and 300 ppmv, showing clear glacial-interglacial variations similar to the result of the Vostok ice core. However, for some periods, the concentration values of the Dome Fuji core are higher by up to 20 ppmv than those of the Vostok core. There is no clear indication that such differences are related to variations of chemical components of Ca 2+ , microparticle and acidity of the Dome Fuji core
Ikehara, Kenji
2016-01-26
It is no doubt quite difficult to solve the riddle of the origin of life. So, firstly, I would like to point out the kinds of obstacles there are in solving this riddle and how we should tackle these difficult problems, reviewing the studies that have been conducted so far. After that, I will propose that the consecutive evolutionary steps in a timeline can be rationally deduced by using a common event as a juncture, which is obtained by two counter-directional approaches: one is the bottom-up approach through which many researchers have studied the origin of life, and the other is the top-down approach, through which I established the [GADV]-protein world hypothesis or GADV hypothesis on the origin of life starting from a study on the formation of entirely new genes in extant microorganisms. Last, I will describe the probable evolutionary process from the formation of Earth to the emergence of life, which was deduced by using a common event-the establishment of the first genetic code encoding [GADV]-amino acids-as a juncture for the results obtained from the two approaches.
Directory of Open Access Journals (Sweden)
Kenji Ikehara
2016-01-01
Full Text Available It is no doubt quite difficult to solve the riddle of the origin of life. So, firstly, I would like to point out the kinds of obstacles there are in solving this riddle and how we should tackle these difficult problems, reviewing the studies that have been conducted so far. After that, I will propose that the consecutive evolutionary steps in a timeline can be rationally deduced by using a common event as a juncture, which is obtained by two counter-directional approaches: one is the bottom-up approach through which many researchers have studied the origin of life, and the other is the top-down approach, through which I established the [GADV]-protein world hypothesis or GADV hypothesis on the origin of life starting from a study on the formation of entirely new genes in extant microorganisms. Last, I will describe the probable evolutionary process from the formation of Earth to the emergence of life, which was deduced by using a common event—the establishment of the first genetic code encoding [GADV]-amino acids—as a juncture for the results obtained from the two approaches.
Directory of Open Access Journals (Sweden)
M. Scherer
2008-03-01
Full Text Available This paper presents an updated trend analysis of water vapour in the lower midlatitude stratosphere from the Boulder balloon-borne NOAA frostpoint hygrometer measurements and from the Halogen Occulation Experiment (HALOE. Two corrections for instrumental bias are applied to homogenise the frostpoint data series, and a quality assessment of all soundings after 1991 is presented. Linear trend estimates based on the corrected data for the period 1980–2000 are up to 40% lower than previously reported. Vertically resolved trends and variability are calculated with a multi regression analysis including the quasi-biennal oscillation and equivalent latitude as explanatory variables. In the range of 380 to 640 K potential temperature (≈14 to 25 km, the frostpoint data from 1981 to 2006 show positive linear trends between 0.3±0.3 and 0.7±0.1%/yr. The same dataset shows trends between −0.2±0.3 and 1.0±0.3%/yr for the period 1992 to 2005. HALOE data over the same time period suggest negative trends ranging from −1.1±0.2 to −0.1±0.1%/yr. In the lower stratosphere, a rapid drop of water vapour is observed in 2000/2001 with little change since. At higher altitudes, the transition is more gradual, with slowly decreasing concentrations between 2001 and 2007. This pattern is consistent with a change induced by a drop of water concentrations at entry into the stratosphere. Previously noted differences in trends and variability between frostpoint and HALOE remain for the homogenised data. Due to uncertainties in reanalysis temperatures and stratospheric transport combined with uncertainties in observations, no quantitative inference about changes of water entering the stratosphere in the tropics could be made with the mid latitude measurements analysed here.
Dose calculation for electrons
International Nuclear Information System (INIS)
Hirayama, Hideo
1995-01-01
The joint working group of ICRP/ICRU is advancing the works of reviewing the ICRP publication 51 by investigating the data related to radiation protection. In order to introduce the 1990 recommendation, it has been demanded to carry out calculation for neutrons, photons and electrons. As for electrons, EURADOS WG4 (Numerical Dosimetry) rearranged the data to be calculated at the meeting held in PTB Braunschweig in June, 1992, and the question and request were presented by Dr. J.L. Chartier, the responsible person, to the researchers who are likely to undertake electron transport Monte Carlo calculation. The author also has carried out the requested calculation as it was the good chance to do the mutual comparison among various computation codes regarding electron transport calculation. The content that the WG requested to calculate was the absorbed dose at depth d mm when parallel electron beam enters at angle α into flat plate phantoms of PMMA, water and ICRU4-element tissue, which were placed in vacuum. The calculation was carried out by the versatile electron-photon shower computation Monte Carlo code, EGS4. As the results, depth dose curves and the dependence of absorbed dose on electron energy, incident angle and material are reported. The subjects to be investigated are pointed out. (K.I.)
Is neutrinoless double beta decay suppressed
International Nuclear Information System (INIS)
Tomoda, T.
1989-01-01
Much effort has been devoted to the study of nuclear double beta decay, since the observation of a neutrinoless double beta (OνΒΒ) decay would be clear evidence that the electron neutrino is a Majorana particle. The OνΒΒ decay is caused by a finite Majorana neutrino mass and/or an admixture of right-handed leptonic currents. In order to relate these quantities to OνΒΒ decay rates, we need nuclear matrix elements, which are model dependent. One of the possibilities of testing nuclear models employed in such analysis is to calculate the experimentally known rates of ΒΒ decay with emission of two neutrinos (2νΒΒ decay) which occurs independently of the nature of the neutrino. There was a long-standing difficulty in such attempts that the calculated 2νΒΒ decay rates turned out to be always too large by one to two orders of magnitude. Trying to overcome such difficulty, Klapdor and Grotz as well as Vogel and Zirnbauer showed in their calculation using schematic effective interactions such that 2νΒΒ decay rates can get reduced considerably due to the nuclear ground state correlations. This paper reports that the suppression is ascribed to that of the virtual Gamow-Teller transitions from the excited 1 + states of the intermediate odd-odd -even nucleus
Progress report, Physics Division, 1 April - 30 June, 1981
International Nuclear Information System (INIS)
1981-08-01
The nuclear physics group obtained an accurate value of the gamow-teller contribution to the 2 + → 2 + (T=1) super allowed β transition in 20 Na from kinematic shifts in the β-delayed α-particle spectrum, thus allowing calculation of the Fermi coupling constant. In experiments with an anti-Compton NaI(Tl) shield, the average properties of the continuum γ-rays were determined for the (HI,xn) reaction and the properties of the high-energy (approximately 14 MeV) giant resonance γ-rays were correlated with specific (HI,xn) reaction channels. A systematic analysis by different techniques showed that recoil distance lifetime measurements can have systematic errors of about 10% from undetected feeding, background and/or hyperfine interactions. Average neutron kinetic energies for the 124 Sn ( 28 Si,5n) 147 Gd reaction correlated very strongly, but unexpectedly, with the bombarding energy. In the High Current Proton Accelerator, beamlet stacking was found to improve injection emittance by a factor of 1.9. The line-shapes of selected phonons in the orientationally disordered crystal β-nitrogen were calculated with the Michel-Nandts model. Computer simulation was used to calculate the spin-wave properties of the disordered ferromagnet Nisub(2)Mnsub(0.8)Vsub(0.2)Sn
International Nuclear Information System (INIS)
Govoni, Marco; Argonne National Lab., Argonne, IL; Galli, Giulia; Argonne National Lab., Argonne, IL
2015-01-01
We present GW calculations of molecules, ordered and disordered solids and interfaces, which employ an efficient contour deformation technique for frequency integration and do not require the explicit evaluation of virtual electronic states nor the inversion of dielectric matrices. We also present a parallel implementation of the algorithm, which takes advantage of separable expressions of both the single particle Green's function and the screened Coulomb interaction. The method can be used starting from density functional theory calculations performed with semilocal or hybrid functionals. The newly developed technique was applied to GW calculations of systems of unprecedented size, including water/semiconductor interfaces with thousands of electrons
Radioactive cloud dose calculations
International Nuclear Information System (INIS)
Healy, J.W.
1984-01-01
Radiological dosage principles, as well as methods for calculating external and internal dose rates, following dispersion and deposition of radioactive materials in the atmosphere are described. Emphasis has been placed on analytical solutions that are appropriate for hand calculations. In addition, the methods for calculating dose rates from ingestion are discussed. A brief description of several computer programs are included for information on radionuclides. There has been no attempt to be comprehensive, and only a sampling of programs has been selected to illustrate the variety available
Kocsis, László; Ounis, Anouar; Chaabani, Fredj; Salah, Neili Mohamed
2013-06-01
Fossil shark teeth and coprolites from three major phosphorite occurrences in the Gafsa Basin (southwestern Tunisia) were investigated for their geochemical compositions to improve local stratigraphy and to better assess paleoenvironmental conditions. 87Sr/86Sr isotope ratios of shark teeth from the Early Maastrichtian El Haria Formation and from the Early Eocene Métlaoui s.s. Formation yielded Sr isotope ages of 68 ± 1 and 47.9 ± 1.3 Ma, respectively, which accord with the expected stratigraphic positions of these sediments. Conversely, shark teeth from the Paleocene-Eocene Chouabine Formation have large variation in Sr isotope ratios even within individual layers. After statistical treatment and then elimination of certain outlier samples, three age-models are proposed and discussed. The most reasonable solution includes three subsequent Sr ages of 61.8 ± 2.2 Ma, 57.2 ± 1.8 and 54.6 ± 1.6 for layer IX, layers VIII-V and layers IV-0, respectively. Three scenarios are discussed for explanation of the presence of the outliers: (1) diagenesis, (2) re-working and (3) locally controlled seawater Sr isotope ratio. The most plausible account for the higher 87Sr/86Sr ratios relative to the global ocean in some fossils is enhanced intrabasinal re-working due to low sea level. Conversely, the sample with lower 87Sr/86Sr than the global seawater may link to diagenesis or to seawater influenced by weathering of Late Cretaceous marine carbonates, which latter is supported by model calculation as well. The ɛNd values of these fossils are very similar to those reported for Paleogene and Late Cretaceous Tethyan seawater and are compatible with the above interpretations. The relatively low oxygen isotope values in shark teeth from the topmost phosphate bed of the Chouabine Formation, together with the Sr isotope results, point toward recovering better connections with the open sea. These δ18O data reflect elevated ambient temperature, which may link to the Early Eocene
Handout on shielding calculation
International Nuclear Information System (INIS)
Heilbron Filho, P.F.L.
1991-01-01
In order to avoid the difficulties of the radioprotection supervisors in the tasks related to shielding calculations, is presented in this paper the basic concepts of shielding theory. It also includes exercises and examples. (author)
Unit Cost Compendium Calculations
U.S. Environmental Protection Agency — The Unit Cost Compendium (UCC) Calculations raw data set was designed to provide for greater accuracy and consistency in the use of unit costs across the USEPA...
PHYSICOCHEMICAL PROPERTY CALCULATIONS
Computer models have been developed to estimate a wide range of physical-chemical properties from molecular structure. The SPARC modeling system approaches calculations as site specific reactions (pKa, hydrolysis, hydration) and `whole molecule' properties (vapor pressure, boilin...
Magnetic Field Grid Calculator
National Oceanic and Atmospheric Administration, Department of Commerce — The Magnetic Field Properties Calculator will computes the estimated values of Earth's magnetic field(declination, inclination, vertical component, northerly...
Intercavitary implants dosage calculation
International Nuclear Information System (INIS)
Rehder, B.P.
The use of spacial geometry peculiar to each treatment for the attainment of intercavitary and intersticial implants dosage calculation is presented. The study is made in patients with intercavitary implants by applying a modified Manchester technique [pt
Casio Graphical Calculator Project.
Stott, Nick
2001-01-01
Shares experiences of a project aimed at developing and refining programs written on a Casio FX9750G graphing calculator. Describes in detail some programs used to develop mental strategies and problem solving skills. (MM)
Small portable speed calculator
Burch, J. L.; Billions, J. C.
1973-01-01
Calculator is adapted stopwatch calibrated for fast accurate measurement of speeds. Single assembled unit is rugged, self-contained, and relatively inexpensive to manufacture. Potential market includes automobile-speed enforcement, railroads, and field-test facilities.
DEFF Research Database (Denmark)
Frederiksen, Morten
2014-01-01
Williamson’s characterisation of calculativeness as inimical to trust contradicts most sociological trust research. However, a similar argument is found within trust phenomenology. This paper re-investigates Williamson’s argument from the perspective of Løgstrup’s phenomenological theory of trust....... Contrary to Williamson, however, Løgstrup’s contention is that trust, not calculativeness, is the default attitude and only when suspicion is awoken does trust falter. The paper argues that while Williamson’s distinction between calculativeness and trust is supported by phenomenology, the analysis needs...... to take actual subjective experience into consideration. It points out that, first, Løgstrup places trust alongside calculativeness as a different mode of engaging in social interaction, rather conceiving of trust as a state or the outcome of a decision-making process. Secondly, the analysis must take...
Hiatt, Arthur A.
1987-01-01
Ten activities that give learners in grades 5-8 a chance to explore mathematics with calculators are provided. The activity cards involve such topics as odd addends, magic squares, strange projects, and conjecturing rules. (MNS)
IRIS core criticality calculations
International Nuclear Information System (INIS)
Jecmenica, R.; Trontl, K.; Pevec, D.; Grgic, D.
2003-01-01
Three-dimensional Monte Carlo computer code KENO-VI of CSAS26 sequence of SCALE-4.4 code system was applied for pin-by-pin calculations of the effective multiplication factor for the first cycle IRIS reactor core. The effective multiplication factors obtained by the above mentioned Monte Carlo calculations using 27-group ENDF/B-IV library and 238-group ENDF/B-V library have been compared with the effective multiplication factors achieved by HELIOS/NESTLE, CASMO/SIMULATE, and modified CORD-2 nodal calculations. The results of Monte Carlo calculations are found to be in good agreement with the results obtained by the nodal codes. The discrepancies in effective multiplication factor are typically within 1%. (author)
Current interruption transients calculation
Peelo, David F
2014-01-01
Provides an original, detailed and practical description of current interruption transients, origins, and the circuits involved, and how they can be calculated Current Interruption Transients Calculationis a comprehensive resource for the understanding, calculation and analysis of the transient recovery voltages (TRVs) and related re-ignition or re-striking transients associated with fault current interruption and the switching of inductive and capacitive load currents in circuits. This book provides an original, detailed and practical description of current interruption transients, origins,
Source and replica calculations
International Nuclear Information System (INIS)
Whalen, P.P.
1994-01-01
The starting point of the Hiroshima-Nagasaki Dose Reevaluation Program is the energy and directional distributions of the prompt neutron and gamma-ray radiation emitted from the exploding bombs. A brief introduction to the neutron source calculations is presented. The development of our current understanding of the source problem is outlined. It is recommended that adjoint calculations be used to modify source spectra to resolve the neutron discrepancy problem
Shielding calculations using FLUKA
International Nuclear Information System (INIS)
Yamaguchi, Chiri; Tesch, K.; Dinter, H.
1988-06-01
The dose equivalent on the surface of concrete shielding has been calculated using the Monte Carlo code FLUKA86 for incident proton energies from 10 to 800 GeV. The results have been compared with some simple equations. The value of the angular dependent parameter in Moyer's equation has been calculated from the locations where the values of the maximum dose equivalent occur. (author)
Mohamed, Abdel-Monem S.; Hosny, A.; Abou-Aly, N.; Saleh, M.; Rayan, A.
2013-06-01
A local geodetic network consisting of eleven benchmarks has been established to study the recent crustal deformation in the Abu-Dabbab area. Seven campaigns of GPS measurements have been collected started from October 2008 and ended in March 2012. The collected data were processed using Bernese version 5.0, and the result values were adjusted to get the more accurate positions of the GPS stations. The magnitudes of horizontal displacements are variable from one epoch to another and in the range of 1-3 (±0.2) mm/yr. Due to the differences in rates of the horizontal displacement; the area is divided into two main blocks. The first one, moves to the east direction of about 3 mm/yr, while the second block, moves to the SW direction of about 6 mm/yr. According to the strain fields that were calculated for the different epochs of measurement, the main force is compression force and is taken the NW-SE to NWW-SEE direction. This force could be because of local and regional tectonic processes affecting on the study area. The maximum values of compression stress are found in the southern central and western part of study area. Estimated accumulation of this strain energy may be considered as an indicator of the possibility of earthquake occurrence. From the seismic tomography study, the 3D Vp and Vp/Vs crustal models indicate high Vp/Vs values forms an elongated anomaly, in the central part of the study area, that extends from a depth of 12 km to about 1-2 km of depth is obtained. By using this crustal model in relocations all seismicity informed that most of the seismicity strongly tend to occur in a cluster manner exactly above the southern part of the study area. Based on the conducted source mechanism study, it is noticed that shallow earthquakes are associated by a high CLVD ratio (up to 40%). Furthermore, initiation of a high level seismic activity, without a large seismic main shock is observed in the Abu-Dabbab area. The distribution of micro-earthquakes tends to
Energy Technology Data Exchange (ETDEWEB)
Birkhan, Jonny Hubertus
2016-07-01
only up to an excitation energy of 60 MeV. Taking into account the excitation energy range from E{sub x}=10 MeV to E{sub x}=60 MeV the polarisability of the nucleus {sup 48}Ca was estimated to be α{sub D}=(2.09±0.02) fm{sup 3}. This result deviates significantly from a theoretical prediction of α{sub D}=(2.31±0.09) fm{sup 3} based on the energy density functional theory. The result of this work could further constrain the range of the parameters of the nuclear models and might give new insights on the neutron skin thickness of {sup 48}Ca as far as a theoretical prediction for the correlation between the polarisability and neutron skin thickness is available especially for the energy region investigated in this work. In the nucleus {sup 48}Ca, almost the full experimentally accessible spin-M1 strength is exhausted by a single spin-flip transition. The corresponding state is the prominent 1{sup +}-state at E{sub x}=10.22 MeV. The configuration of the nucleus {sup 48}Ca leads to nearly pure spin-flip transitions of the neutrons. In this case the isoscalar transition matrix element is as large as the isovector one. This means that the nucleus {sup 48}Ca is a reference case whereas the nucleus {sup 208}Pb is another one because its isoscalar and isovector M1 strength is well separated. The extraction of the total electromagnetic M1 strength was based on a method that had been successfully applied to Gamow-Teller transitions in other analyses in the framework of a distorted wave impulse approximation. This method allows to calculate the strength from the measured isovector cross section at θ{sub CM}=0 mainly by a single conversion factor, the so-called ''unit cross section''. The method was used for the analysis of this work assuming that isospin symmetry is given for isobars and that the unit cross section is the same for isovector spin-M1 excitations as well as for the excitations of analogue states. The problem was to extract the isovector part of
We propose to use the new ISOLDE decay station and the neutron detector VANDLE to measure the $\\beta$-delayed neutron emission of N=82-84 $^{130-132}$Cd isotopes. The large delayed neutron emission probability observed in a previous ISOLDE measurement is indicative of the Gamow-Teller transitions due to the decay of deep core neutrons. Core Gamow-Teller decay has been experimentally proven in the $^{78}$Ni region for the N>50 nuclei using the VANDLE array. The spectroscopic measurement of delayed neutron emission along the cadmium isotopic chain will allow us to track the evolution of the single particle states and the shell gap.
Structure of β-decay strength functions
International Nuclear Information System (INIS)
Naumov, Y.V.; Bykov, A.A.; Izosimov, I.N.
1983-01-01
The experimental and theoretical studies on the structure of the Gamow--Teller β-decay strength functions are reviewed. Also considered are processes such as M1 γ decay of analog states, the emission of delayed protons, neutrons, and α particles, delayed fission, and the (p, n) reaction at proton energies 100--200 MeV. The results of measurements of the strength functions by γ-ray total absorption are analyzed. It is shown that the β + decay of nuclei far from the stability band exhibits a new type of collective charge-exchange excitation: Gamow--Teller resonance with μ/sub tau/ = +1
International Nuclear Information System (INIS)
Luo Mingkun; Wang Fei; Huang Wei; Zhang Wenqi; Zhao Shan; Lu Lianghong
2001-01-01
A kind of approximate theoretical calculating formula of the vertical U-bend tube natural-circuit steam generator is deduced by using an approximate method, the results of this formula is compared with the heat exchanging areas of the real vertical U-bend tube natural-circuit steam generators, the absolute errors of them are below 8%
Uncertainty calculations made easier
International Nuclear Information System (INIS)
Hogenbirk, A.
1994-07-01
The results are presented of a neutron cross section sensitivity/uncertainty analysis performed in a complicated 2D model of the NET shielding blanket design inside the ITER torus design, surrounded by the cryostat/biological shield as planned for ITER. The calculations were performed with a code system developed at ECN Petten, with which sensitivity/uncertainty calculations become relatively simple. In order to check the deterministic neutron transport calculations (performed with DORT), calculations were also performed with the Monte Carlo code MCNP. Care was taken to model the 2.0 cm wide gaps between two blanket segments, as the neutron flux behind the vacuum vessel is largely determined by neutrons streaming through these gaps. The resulting neutron flux spectra are in excellent agreement up to the end of the cryostat. It is noted, that at this position the attenuation of the neutron flux is about 1 l orders of magnitude. The uncertainty in the energy integrated flux at the beginning of the vacuum vessel and at the beginning of the cryostat was determined in the calculations. The uncertainty appears to be strongly dependent on the exact geometry: if the gaps are filled with stainless steel, the neutron spectrum changes strongly, which results in an uncertainty of 70% in the energy integrated flux at the beginning of the cryostat in the no-gap-geometry, compared to an uncertainty of only 5% in the gap-geometry. Therefore, it is essential to take into account the exact geometry in sensitivity/uncertainty calculations. Furthermore, this study shows that an improvement of the covariance data is urgently needed in order to obtain reliable estimates of the uncertainties in response parameters in neutron transport calculations. (orig./GL)
Interplay of quasiparticle-vibration coupling and pairing correlations on β-decay half-lives
Niu, Y. F.; Niu, Z. M.; Colò, G.; Vigezzi, E.
2018-05-01
The nuclear β-decay half-lives of Ni and Sn isotopes, around the closed shell nuclei 78Ni and 132Sn, are investigated by computing the distribution of the Gamow-Teller strength using the Quasiparticle Random Phase Approximation (QRPA) with quasiparticle-vibration coupling (QPVC), based on ground-state properties obtained by Hartree-Fock-Bogoliubov (HFB) calculations. We employ the effective interaction SkM* and a zero-range effective pairing force. The half-lives are strongly reduced by including the QPVC. We study in detail the effects of isovector (IV) and isoscalar (IS) pairing. Increasing the IV strength tends to increase the lifetime for nuclei in the proximity of, but lighter than, the closed-shell ones in QRPA calculations, while the effect is significantly reduced by taking into account the QPVC. On the contrary, the IS pairing mainly plays a role for nuclei after the shell closure. Increasing its strength decreases the half-lives, and the effect at QRPA and QRPA+QPVC level is comparable. The effect of IS pairing is particularly pronounced in the case of the Sn isotopes, where it turns out to be instrumental to obtain good agreement with experimental data.
The nuclear spin response to intermediate energy protons and deuterons at low momentum transfer
International Nuclear Information System (INIS)
Baker, F.T.; Djalali, C.; Glashausser, C.; Lenske, H.; Love, W.G.; Tomasi-Gustafsson, E.; Wambach, J.
1997-01-01
Measurements of polarization transfer in the inelastic scattering of intermediate energy protons and deuterons have yielded a wealth of data on the spin response of nuclei. This work complements the well-known studies of Gamow-Teller strength in charge-exchange reactions. The emphasis here is on a consistent determination of the S=1, T=0 response, practical only with deuterons, and on the proper separation of S=0 and S=1 strength in proton spectra for appropriate comparison with sum rules. We concentrate on two nuclei, 40 Ca and 12 C, at momentum transfers below about 1 fm -1 and on excitations up to about 50 MeV. The continuum second random phase approximation provides the primary theoretical tool for calculating and interpreting the response in terms of properties of the nucleon-nucleon force inside the nuclear medium. The reaction mechanism is described by the DWIA, applied here to continuum proton scattering almost as rigorously as it is usually applied to low energy excitations. A new DWIA formalism for the description of spin observables in deuteron scattering is used. Comparison of the proton and deuteron data with each other and with RPA/DWIA calculations yields interesting insights into the current state of understanding of collectivity and the nuclear spin response. (orig.)
International Nuclear Information System (INIS)
Hannen, V.M.; Van den Berg, A.M.; Bieber, R.K.; Harakeh, M.N.; De Huu, M.A.; Kruesemann, B.A.M.; Van der Werf, S.Y.; Woertche, H.J.; Amos, K.; Deb, P.K.; Ellinghaus, F.; Frekers, D.; Rakers, S.; Schmidt, R.; Hagemann, M.
2001-01-01
Cross sections and analyzing powers for the 11 B(p.p') reaction have been measured using a 150 MeV polarized proton beam from the AGOR cyclotron at KVI. For the stronger inelastic transitions, also spin-flip probabilities have been extracted. A fully microscopic distorted-wave analysis of the elastic and inelastic data has been made, using density-dependent effective interactions and input from shell-model calculations in a complete (0+2) ℎω model space for normal parity transitions and in a 1 ℎω model space for non-normal parity transitions. With the help of these model calculations spin-isovector M1 strengths for the negative-parity states at excitation energies of 2.125 MeV (J π = 1/2 - ), 4.445 MeV (J π 5/2 - ), 5.020 MeV (J π = 3/2 - ) and 8.920 MeV (J π 5/2 - ) have been extracted and compared to known Gamow-Teller strengths for the analog transitions to 11 C
International Nuclear Information System (INIS)
Suzuki, T.; Sagawa, H.
2000-01-01
Complete text of publication follows. Spin and isospin modes in nuclei are investigated. We discuss some of the following topics. 1. Spin-dipole excitations in 12 C and 16 O are studied (1). Effects of tensor and spin-orbit interactions on the distribution of the strengths are investigated, and neutral current neutrino scattering cross sections in 16 O are obtained for heavy-flavor neutrinos from the supernovae. 2. Gamow-Teller (GT) and spin-dipole (SD) modes in 208 Bi are investigated. Quenching and fragmentation of the GT strength are discussed (2). SD excitations and electric dipole (E1) transitions between the GT and SD states are studied (3). Calculated E1 strengths are compared with the sum rule values obtained within the 1p-1h and 1p-1h + 2p-2h configuration spaces. 3. Coulomb displacement energy (CDE) of the IAS of 14 Be is calculated, and the effects of the halo on the CDE and the configuration of the halo state are investigated. 4. Spreading width of IAS and isospin dependence of the width are investigated (4). Our formula for the width explains very well the observed isospin dependence (5). (author)
Progress in research, April 1, 1992--March 31, 1993, Texas A and M University Cyclotron Institute
Energy Technology Data Exchange (ETDEWEB)
NONE
1993-07-01
This Institute annual report for the period 1 April 1992--31 March 1993 covers a period which has seen the initial runs of three new spectrometers which constitute a major portion of the new detection capabilities developed for this facility. These devices are the Proton Spectrometer (PSP), the Mass Achromat Recoil Mass Spectrometer (MARS), and the Multipole dipole Multipole (MDM) Particle Spectrometer. These devices are now available to pursue the studies of Gamow Teller states, reactions of astrophysical interest, and giant resonance studies for which they were constructed, as well as for other experiments. A beam analysis system which will deliver high resolution beams to the MDM spectrometer is currently under construction. With the completion of these spectrometer projects, the facility emphasis is now focused on the development of the full capabilities of the K500 cyclotron and on the research program. During the report period, the ECR-K500 cyclotron combination operated 5,849 hours. Theoretical work reported in this document ranges from nuclear structure calculations using the IBM-2 model to calculations of kaon production and the in-medium properties of the rho and phi mesons, the latter as a probe of the QCD phase transition. Nuclear dynamics and exotic shapes and fragmentation modes of hot nuclei are also addressed. In atomic physics, new measurements of x-ray emission from highly ionized ions, of molecular dissociation and of surface interactions are reported.
Progress in research, April 1, 1992 - March 31, 1993, Texas A and M University Cyclotron Institute
International Nuclear Information System (INIS)
1993-07-01
This Institute annual report for the period 1 April 1992--31 March 1993 covers a period which has seen the initial runs of three new spectrometers which constitute a major portion of the new detection capabilities developed for this facility. These devices are the Proton Spectrometer (PSP), the Mass Achromat Recoil Mass Spectrometer (MARS), and the Multipole dipole Multipole (MDM) Particle Spectrometer. These devices are now available to pursue the studies of Gamow Teller states, reactions of astrophysical interest, and giant resonance studies for which they were constructed, as well as for other experiments. A beam analysis system which will deliver high resolution beams to the MDM spectrometer is currently under construction. With the completion of these spectrometer projects, the facility emphasis is now focused on the development of the full capabilities of the K500 cyclotron and on the research program. During the report period, the ECR-K500 cyclotron combination operated 5,849 hours. Theoretical work reported in this document ranges from nuclear structure calculations using the IBM-2 model to calculations of kaon production and the in-medium properties of the rho and phi mesons, the latter as a probe of the QCD phase transition. Nuclear dynamics and exotic shapes and fragmentation modes of hot nuclei are also addressed. In atomic physics, new measurements of x-ray emission from highly ionized ions, of molecular dissociation and of surface interactions are reported
Nuclear chiral axial currents and applications to few-nucleon systems
Energy Technology Data Exchange (ETDEWEB)
Baroni, Alessandro [Old Dominion Univ., Norfolk, VA (United States)
2017-08-01
This Thesis is divided into three main parts. The first part discusses basic aspects of chiral effective field theory and the formalism, based on time ordered perturbation theory, used to to derive the nuclear potentials and currents from the chiral Lagrangians. The second part deals with the actual derivation, up to one loop, of the two-nucleon potential and one- and two-nucleon weak axial charge and current. In both derivations ultraviolet divergences generated by loop corrections are isolated using dimensional regularization. The resulting axial current is finite and conserved in the chiral limit, while the axial charge requires renormalization. A complete set of contact terms for the axial charge up to the relevant order in the power counting is constructed. The third part of this Thesis discusses two applications: (i) the calculation of the Gamow-Teller matrix element of tritium, used to constrain the single low-energy constant entering the axial current; (ii) the calculation of neutrino-deuteron inclusive cross sections at low energies. These results have confirmed previous predictions obtained in phenomenological approaches. These latter studies have played an important role in the analysis and interpretation of experiments at the Sudbury Neutrino Observatory.
Wisniewski, H.; Gourdain, P.-A.
2017-10-01
APOLLO is an online, Linux based plasma calculator. Users can input variables that correspond to their specific plasma, such as ion and electron densities, temperatures, and external magnetic fields. The system is based on a webserver where a FastCGI protocol computes key plasma parameters including frequencies, lengths, velocities, and dimensionless numbers. FastCGI was chosen to overcome security problems caused by JAVA-based plugins. The FastCGI also speeds up calculations over PHP based systems. APOLLO is built upon the WT library, which turns any web browser into a versatile, fast graphic user interface. All values with units are expressed in SI units except temperature, which is in electron-volts. SI units were chosen over cgs units because of the gradual shift to using SI units within the plasma community. APOLLO is intended to be a fast calculator that also provides the user with the proper equations used to calculate the plasma parameters. This system is intended to be used by undergraduates taking plasma courses as well as graduate students and researchers who need a quick reference calculation.
Su, Zhi-Hui; Imura, Yûki; Osawa, Syozo
2005-11-07
We deduced the phylogenetic relationships of 54 individuals representing 27 species of the Calosomina (Coleoptera, Carabidae) from various regions of the world from the mitochondrial NADH dehydrogenase subunit 5 (ND 5) gene sequences. The results suggest that these Calosomina radiated into 17 lineages within a short time about 30 million years ago (Mya). Most of the lineages are composed of a single genus containing only one or a few species. In some cases, several species classified into the same genus (e.g., Calosoma maximowiczi, Calos. inquisitor and Calos. frigidum) appear separately in independent lineages, while in others a series of species classified into different genera fall into one lineage (e.g., Chrysostigma calidum, Blaptosoma chihuahua, Microcallisthenes wilkesi and Callisthenes spp.). Based on this molecular phylogeny and morphological data, the probable evolutionary history and mode of morphological differentiation of the Calosomina are discussed.
Daylight calculations in practice
DEFF Research Database (Denmark)
Iversen, Anne; Roy, Nicolas; Hvass, Mette
The aim of the project was to obtain a better understanding of what daylight calculations show and also to gain knowledge of how the different daylight simulation programs perform compared with each other. Experience has shown that results for the same room, obtained from two daylight simulation...... programs can give different results. This can be due to restrictions in the program itself and/or be due to the skills of the persons setting up the models. This is crucial as daylight calculations are used to document that the demands and recommendations to daylight levels outlined by building authorities....... The aim of the project was to obtain a better understanding of what daylight calculations show and also to gain knowledge of how the different daylight simulation programs perform compared with each other. Furthermore the aim was to provide knowledge of how to build up the 3D models that were...
Salgado, C A; Salgado, Carlos A.; Wiedemann, Urs Achim
2003-01-01
We calculate the probability (``quenching weight'') that a hard parton radiates an additional energy fraction due to scattering in spatially extended QCD matter. This study is based on an exact treatment of finite in-medium path length, it includes the case of a dynamically expanding medium, and it extends to the angular dependence of the medium-induced gluon radiation pattern. All calculations are done in the multiple soft scattering approximation (Baier-Dokshitzer-Mueller-Peign\\'e-Schiff--Zakharov ``BDMPS-Z''-formalism) and in the single hard scattering approximation (N=1 opacity approximation). By comparison, we establish a simple relation between transport coefficient, Debye screening mass and opacity, for which both approximations lead to comparable results. Together with this paper, a CPU-inexpensive numerical subroutine for calculating quenching weights is provided electronically. To illustrate its applications, we discuss the suppression of hadronic transverse momentum spectra in nucleus-nucleus colli...
Three recent TDHF calculations
International Nuclear Information System (INIS)
Weiss, M.S.
1981-05-01
Three applications of TDHF are discussed. First, vibrational spectra of a post grazing collision 40 Ca nucleus is examined and found to contain many high energy components, qualitatively consistent with recent Orsay experiments. Second, the fusion cross section in energy and angular momentum are calculated for 16 O + 24 Mg to exhibit the parameters of the low l window for this system. A sensitivity of the fusion cross section to the effective two body potential is discussed. Last, a preliminary analysis of 86 Kr + 139 La at E/sub lab/ = 505 MeV calculated in the frozen approximation is displayed, compared to experiment and discussed
Fission neutron multiplicity calculations
International Nuclear Information System (INIS)
Maerten, H.; Ruben, A.; Seeliger, D.
1991-01-01
A model for calculating neutron multiplicities in nuclear fission is presented. It is based on the solution of the energy partition problem as function of mass asymmetry within a phenomenological approach including temperature-dependent microscopic energies. Nuclear structure effects on fragment de-excitation, which influence neutron multiplicities, are discussed. Temperature effects on microscopic energy play an important role in induced fission reactions. Calculated results are presented for various fission reactions induced by neutrons. Data cover the incident energy range 0-20 MeV, i.e. multiple chance fission is considered. (author). 28 refs, 13 figs
Lattice cell burnup calculation
International Nuclear Information System (INIS)
Pop-Jordanov, J.
1977-01-01
Accurate burnup prediction is a key item for design and operation of a power reactor. It should supply information on isotopic changes at each point in the reactor core and the consequences of these changes on the reactivity, power distribution, kinetic characters, control rod patterns, fuel cycles and operating strategy. A basic stage in the burnup prediction is the lattice cell burnup calculation. This series of lectures attempts to give a review of the general principles and calculational methods developed and applied in this area of burnup physics
Energy Technology Data Exchange (ETDEWEB)
Trkov, A; Ravnik, M; Zeleznik, N [Inst. Jozef Stefan, Ljubljana (Slovenia)
1992-07-01
Functional description of the programme package Cord-2 for PWR core design calculations is presented. Programme package is briefly described. Use of the package and calculational procedures for typical core design problems are treated. Comparison of main results with experimental values is presented as part of the verification process. (author) [Slovenian] Opisali smo programski paket CORD-2, ki se uporablja pri projektnih izracunih sredice pri upravljanju tlacnovodnega reaktorja. Prikazana je uporaba paketa in racunskih postopkov za tipicne probleme, ki nastopajo pri projektiranju sredice. Primerjava glavnih rezultatov z eksperimentalnimi vrednostmi je predstavljena kot del preveritvenega procesa. (author)
Allswang, John M.
1986-01-01
This article provides two short microcomputer gradebook programs. The programs, written in BASIC for the IBM-PC and Apple II, provide statistical information about class performance and calculate grades either on a normal distribution or based on teacher-defined break points. (JDH)
Cardiovascular risk calculation
African Journals Online (AJOL)
James A. Ker
2014-08-20
Aug 20, 2014 ... smoking and elevated blood sugar levels (diabetes mellitus). These risk ... These are risk charts, e.g. FRS, a non-laboratory-based risk calculation, and ... for hard cardiovascular end-points, such as coronary death, myocardial ...
International Nuclear Information System (INIS)
Simonkova, J.
1988-01-01
The problems are summed up of the dynamic calculation of cooling towers with forced and natural air draft. The quantities and relations are given characterizing the simultaneous exchange of momentum, heat and mass in evaporative water cooling by atmospheric air in the packings of cooling towers. The method of solution is clarified in the calculation of evaporation criteria and thermal characteristics of countercurrent and cross current cooling systems. The procedure is demonstrated of the calculation of cooling towers, and correction curves and the effect assessed of the operating mode at constant air number or constant outlet air volume flow on their course in ventilator cooling towers. In cooling towers with the natural air draft the flow unevenness is assessed of water and air relative to its effect on the resulting cooling efficiency of the towers. The calculation is demonstrated of thermal and resistance response curves and cooling curves of hydraulically unevenly loaded towers owing to the water flow rate parameter graded radially by 20% along the cross-section of the packing. Flow rate unevenness of air due to wind impact on the outlet air flow from the tower significantly affects the temperatures of cooled water in natural air draft cooling towers of a design with lower demands on aerodynamics, as early as at wind velocity of 2 m.s -1 as was demonstrated on a concrete example. (author). 11 figs., 10 refs
Hypervelocity impact cratering calculations
Maxwell, D. E.; Moises, H.
1971-01-01
A summary is presented of prediction calculations on the mechanisms involved in hypervelocity impact cratering and response of earth media. Considered are: (1) a one-gram lithium-magnesium alloys impacting basalt normally at 6.4 km/sec, and (2) a large terrestrial impact corresponding to that of Sierra Madera.
Languages for structural calculations
International Nuclear Information System (INIS)
Thomas, J.B.; Chambon, M.R.
1988-01-01
The differences between human and computing languages are recalled. It is argued that they are to some extent structured in antagonistic ways. Languages in structural calculation, in the past, present, and future, are considered. The contribution of artificial intelligence is stressed [fr
Energy Technology Data Exchange (ETDEWEB)
Brockway, D.; Soran, P.; Whalen, P.
1985-01-01
A Monte Carlo algorithm to efficiently calculate static alpha eigenvalues, N = ne/sup ..cap alpha..t/, for supercritical systems has been developed and tested. A direct Monte Carlo approach to calculating a static alpha is to simply follow the buildup in time of neutrons in a supercritical system and evaluate the logarithmic derivative of the neutron population with respect to time. This procedure is expensive, and the solution is very noisy and almost useless for a system near critical. The modified approach is to convert the time-dependent problem to a static ..cap alpha../sup -/eigenvalue problem and regress ..cap alpha.. on solutions of a/sup -/ k/sup -/eigenvalue problem. In practice, this procedure is much more efficient than the direct calculation, and produces much more accurate results. Because the Monte Carlo codes are intrinsically three-dimensional and use elaborate continuous-energy cross sections, this technique is now used as a standard for evaluating other calculational techniques in odd geometries or with group cross sections.
International Nuclear Information System (INIS)
Devooght, J.; Lefvert, T.; Stankiewiez, J.
1981-01-01
This chapter deals with the work done in reactor dynamics within the Coordinated Research Program on Transport Theory and Advanced Reactor Calculations by three groups in Belgium, Poland, Sweden and Italy. Discretization methods in diffusion theory, collision probability methods in time-dependent neutron transport and singular perturbation method are represented in this paper
Equilibrium fission model calculations
International Nuclear Information System (INIS)
Beckerman, M.; Blann, M.
1976-01-01
In order to aid in understanding the systematics of heavy ion fission and fission-like reactions in terms of the target-projectile system, bombarding energy and angular momentum, fission widths are calculated using an angular momentum dependent extension of the Bohr-Wheeler theory and particle emission widths using angular momentum coupling
Low-spin structure of 51,35,86Br and 50,36,86Kr nuclei: The role of the g7 /2 neutron orbital
Urban, W.; Sieja, K.; Materna, T.; Czerwiński, M.; Rząca-Urban, T.; Blanc, A.; Jentschel, M.; Mutti, P.; Köster, U.; Soldner, T.; de France, G.; Simpson, G. S.; Ur, C. A.; Bernards, C.; Fransen, C.; Jolie, J.; Regis, J.-M.; Thomas, T.; Warr, N.
2016-10-01
Low-spin excited levels in 51,35,86Br and 50,36,86Kr, populated following β- decay and the neutron-induced fission of 235U, were measured using the Lohengrin fission-fragment separator and the EXILL array of Ge detectors at the PF1B cold-neutron facility of the Institute Laue-Langevin Grenoble. Improved populations of excited levels in 86Br remove inconsistencies existing in the literature on this nucleus. Directional-linear-polarization correlations, analyzed using newly developed formulas, as well as precise angular correlations allowed the unique 1- and 2- spin and parity assignments to the ground state of 86Br and the 4016.3-keV level in 86Kr, respectively. Based on these results we propose that the Gamow-Teller β- decays of 86Se and 86Br involve the ν g7 /2→π g9 /2 transition in addition to the ν p3 /2→π p3 /2 transition proposed earlier. In 86Kr we have identified 11+, 23+, and 31+ levels, analogous to the mixed-symmetry states in 94Mo, which in 86Kr are from proton excitations, only. Large-scale, shell-model calculations with refined interactions reproduce well excitations in 86Br and 86Kr and support our interpretations.
Relativistic mean field theory for unstable nuclei
International Nuclear Information System (INIS)
Toki, Hiroshi
2000-01-01
We discuss the properties of unstable nuclei in the framework of the relativistic mean field (RMF) theory. We take the RMF theory as a phenomenological theory with several parameters, whose form is constrained by the successful microscopic theory (RBHF), and whose values are extracted from the experimental values of unstable nuclei. We find the outcome with the newly obtained parameter sets (TM1 and TMA) is promising in comparison with various experimental data. We calculate systematically the ground state properties of even-even nuclei up to the drip lines; about 2000 nuclei. We find that the neutron magic shells (N=82, 128) at the standard magic numbers stay at the same numbers even far from the stability line and hence provide the feature of the r-process nuclei. However, many proton magic numbers disappear at the neutron numbers far away from the magic numbers due to the deformations. We discuss how to describe giant resonances for the case of the non-linear coupling terms for the sigma and omega mesons in the relativistic RPA. We mention also the importance of the relativistic effect on the spin observables as the Gamow-Teller strength and the longitudinal and transverse spin responses. (author)
Energy Technology Data Exchange (ETDEWEB)
Robin, Caroline; Litvinova, Elena [Western Michigan University, Department of Physics, Kalamazoo, MI (United States)
2016-07-15
A new theoretical approach to spin-isospin excitations in open-shell nuclei is presented. The developed method is based on the relativistic meson-exchange nuclear Lagrangian of Quantum Hadrodynamics and extends the response theory for superfluid nuclear systems beyond relativistic quasiparticle random phase approximation in the proton-neutron channel (pn-RQRPA). The coupling between quasiparticle degrees of freedom and collective vibrations (phonons) introduces a time-dependent effective interaction, in addition to the exchange of pion and ρ-meson taken into account without retardation. The time-dependent contributions are treated in the resonant time-blocking approximation, in analogy to the previously developed relativistic quasiparticle time-blocking approximation (RQTBA) in the neutral (non-isospin-flip) channel. The new method is called proton-neutron RQTBA (pn-RQTBA) and is applied to the Gamow-Teller resonance in a chain of neutron-rich nickel isotopes {sup 68-78}Ni. A strong fragmentation of the resonance along with quenching of the strength, as compared to pn-RQRPA, is obtained. Based on the calculated strength distribution, beta-decay half-lives of the considered isotopes are computed and compared to pn-RQRPA half-lives and to experimental data. It is shown that a considerable improvement of the half-life description is obtained in pn-RQTBA because of the spreading effects, which bring the lifetimes to a very good quantitative agreement with data. (orig.)
The ``Folk Theorem'' on effective field theory: How does it fare in nuclear physics?
Rho, Mannque
2017-10-01
This is a brief history of what I consider as very important, some of which truly seminal, contributions made by young Korean nuclear theorists, mostly graduate students working on PhD thesis in 1990s and early 2000s, to nuclear effective field theory, nowadays heralded as the first-principle approach to nuclear physics. The theoretical framework employed is an effective field theory anchored on a single scale-invariant hidden local symmetric Lagrangian constructed in the spirit of Weinberg's "Folk Theorem" on effective field theory. The problems addressed are the high-precision calculations on the thermal np capture, the solar pp fusion process, the solar hep process — John Bahcall's challenge to nuclear theorists — and the quenching of g A in giant Gamow-Teller resonances and the whopping enhancement of first-forbidden beta transitions relevant in astrophysical processes. Extending adventurously the strategy to a wild uncharted domain in which a systematic implementation of the "theorem" is far from obvious, the same effective Lagrangian is applied to the structure of compact stars. A surprising, unexpected, result on the properties of massive stars, totally different from what has been obtained up to day in the literature, is predicted, such as the precocious onset of conformal sound velocity together with a hint for the possible emergence in dense matter of hidden symmetries such as scale symmetry and hidden local symmetry.
Additional results from the β-delayed proton decays of 27P and 31Cl
International Nuclear Information System (INIS)
Ognibene, T.J.; Powell, J.; Moltz, D.M.; Rowe, M.W.; Cerny, J.
1996-01-01
β-delayed proton decays of the nuclides 27 P and 31 Cl were measured using the helium-jet recoil collection technique and low-energy particle identification detector telescopes. In 27 P, two new proton groups at 466±3 keV and 612±2 keV, with intensities of 9±2% and 97±3% relative to the main (100%) group at 731±2 keV, were discovered. Additionally, during the 27 P experiments, a new proton transition was identified following the β decay of 28 P. This group, at a proton energy of 1452±4 keV, had a 2±1% intensity relative to the 100% group at 679±1 keV. A total 27 P β-delayed proton branch of 0.07% was estimated. The experimental Gamow-Teller β-decay strengths of the observed transitions from 27 P were compared to results from shell model calculations. A search for new proton transitions in 31 Cl, the next member of this A=4n+3, T z =-3/2 series, was unsuccessful. However, several proton peaks that had been previously assigned to 31 Cl decay were shown to be from the decay of 25 Si. copyright 1996 The American Physical Society
Spin dipole and quadrupole resonances in 40Ca
International Nuclear Information System (INIS)
Baker, F.T.; Love, W.G.; Bimbot, L.; Fergerson, R.W.; Glashausser, C.; Green, A.; Jones, K.; Nanda, S.
1989-01-01
Angular distributions of the double differential cross section d 2 σ/dΩ dE(σ) and the spin-flip probability S nn have been measured for inclusive proton inelastic scattering from 40 Ca at 319 MeV. Excitation energies (ω) up to about 40 MeV have been investigated over the angular range from 3.5 degree to 12 degree in the laboratory (0.3 to 0.9 fm -1 ). Here, multipole decompositions of angular distributions of σS nn for the 40 Ca(rvec p,rvec p ') reaction at 319 MeV have been performed in order to compare ΔS=1 strength observed with sum rules. In contrast to the well-known quenching of Gamow-Teller and M1 resonances, the spin-dipole resonance has a total measured strength which is larger than that predicted by the energy-weighted sum rule. The spin-dipole strength distribution supports asymmetric widths predicted by calculations including 2p-2h mixing. The spin-quadrupole resonance is observed near ω=35 MeV and its total strength for ω<40 MeV estimated
Temperature dependence of pair correlations in nuclei in the iron region
International Nuclear Information System (INIS)
Langanke, K.; Dean, D.J.; Oak Ridge National Lab., TN; Radha, P.B.; Koonin, S.E.
1996-01-01
We use the shell-model Monte Carlo approach to study thermal properties and pair correlations in 54,56,58 Fe and in 56 Cr. The calculations are performed with the modified Kuo-Brown interaction in the complete 1p0f model space. We find generally that the proton-proton and neutron-neutron J=0 pairing correlations, which dominate the ground-state properties of even-even nuclei, vanish at temperatures around 1 MeV. This pairing phase transition is accompanied by a rapid increase in the moment of inertia and a partial unquenching of the M1 strength. We find that the M1 strength totally unquenches at higher temperatures, related to the vanishing of isoscalar proton-neutron correlations, which persist to higher temperatures than the pairing between like nucleons. The Gamow-Teller strength is also correlated to the isoscalar proton-neutron pairing and hence also unquenches at a temperature larger than that of the pairing phase transition. (orig.)
Elucidation of impact of tensor force on the β decay of magic and semi-magic nuclei
International Nuclear Information System (INIS)
Minato, Futoshi
2016-01-01
The authors theoretically examined the β decay of neutron-rich nuclei with a magic number and semi-magic number, using a proton-neutron random phase approximation method. The tensor force previously believed to have a significant impact on the development of the structure of unstable nuclei was found to potentially have an impact on β decay, too. This paper introduces how β decay half-life is reproduced by the tensor force, with a focus on its microscopic mechanism. It was found that the tensor force plays an important role in the β decay of 34 Si, 68,78 Ni, and 132 Sn. Although the calculation of Gamow-Teller transition (GT transition) leaves room for theoretical confirmation, it is clear that the tensor force has a large impact on the 1+ excited state of GT transition. Therefore, for the reliable prediction of the β decay half-life of unknown nuclei, it is necessary to take into account the impact of tensor force. β decay, along with the mass, radius, and excited state, is one of the characteristics possessed by unstable nuclei, and it is important to increase the knowledge of nuclear structure theory so as to be able to systematically predict the probability of β decay. (A.O.)
Axial charge of the weak nucleon current extracted from the β decays of spin aligned 12B and 12N
International Nuclear Information System (INIS)
Yamaguchi, Takayuki
1998-01-01
The alignment correlation terms in the β-ray angular distributions of the 12 B and 12 N mirror nuclei have been precisely measured, in order to investigate the mesonic effect in the axial charge matrix element. The spin alignments were created with the spin manipulation technique in the β-NMR method, which has been improved based on the recent studies of hyperfine interactions of 12 B and 12 N in a Mg crystal. From the sum of the alignment correlation terms, the ratio of the axial charge to the Gamow-Teller term was determined to be y = 4.66 ± 0.06(stat) ± 0.13(syst). The present result gives clear evidence of the mesonic effect in the axial charge and even more shows 16 ± 6% enhancement over the full calculation which includes the meson exchange effect and the core polarization effect. A possible mass renormalization for the decaying nucleon in a finite nucleon density explains this enhancement. (author)
The Structure of the Heavy Calcium Isotopes and the Effective Interaction in the sd-fp Shell
Dorvaux, O; Nowacki, F; Courtin, S; Marechal, F; Siiskonen, T M; Perrot, F; Pietri, S B
2002-01-01
Nuclei with 40 $<$ A $<$ 56, near the stability line, are very well described in the frame of the shell model. However, when the number of neutrons increases, the situation becomes more complex which explains why the interaction can be found very dissimilar within different calculations. Heavy Ca isotopes, because of the simplicity of their wave-functions, correspond to the optimal choice to fix unambiguously the interaction in this mass region.\\\\ It is proposed to measure the $\\beta$-decay of $^{51, 52, 53}$K with the help of an utmost performing neutron (TONNERRE array) and $\\gamma$- (Miniball clusters) detection, allowing efficient coincidence measurements. This will allow the lowest lying Gamow-Teller states to be located in $^{51, 52, 53}$Ca, and the still unknown properties of natural parity states to be investigated. The awaited results should allow to settle the n-n interaction in the fp shell and the Gnp matrix accross the sd and fp shells, one step farther from stability, by comparison with fu...
Conserving RPA and the response of 48Ca
International Nuclear Information System (INIS)
Brand, M.G.E.; Allaart, K.; Dickhoff, W.H.
1988-01-01
The connection between the single-particle self-energy and the corresponding conserving particle-hole (ph) interaction, discussed long ago by Kadanoff and Baym, is employed to study the response of 48 Ca. Second order self-energy contributions are taken into account in the construction of the energy dependent ph interaction. From this perspective it is possible to make contact with other approaches which also aim to incorporate the coupling to 2p2h excitations within the RPA framework. The method is used to study both the discrete low-energy states as well as the giant resonances in both 48 Ca and 48 Sc using a realistic G matrix interaction based on meson exchange. The calculated strength distribution compares favorably with experimental but the strength below 15 MeV is still somewhat too large as compared to experiment for all types of excitations. The quenching of magnetic and Gamow-Teller strength due to 2p2h admixture amounts to about 30%. (orig.)
Shell structure from N=Z (100Sn) to N>>Z (78Ni)
International Nuclear Information System (INIS)
Grawe, H.
2003-01-01
The shell structure of 100 Sn shows striking resemblance to 56 Ni one major shell below. Large-scale shell model calculations employing realistic interactions derived from effective NN potentials and allowing for up to 4p4h excitations of the 100 Sn core account very well for the spectroscopy of key neighbours 102,103 Sn, 98 Cd and 94 Ag, as inferred from level energies, isomerism, E2 strengths and Gamow-Teller (GT) decay of high-spin states. Recent β- decay studies of 101-104 Sn using the sulphurisation ISOL technique open the perspective to study the 100 Sn GT resonance. At N>>Z the persistence of the N=50 and the weakness of the N=40 shells are traced back to the monopole interaction in S=0 proton-neutron (πν) pairs of nucleons, a scenario which can be generalised to account for the new N=6,16(14),34(32) magicity in light neutron-rich nuclei. (orig.)
International Nuclear Information System (INIS)
Weill, J.; Tellier; Bonnemay; Craigne; Chareton; Di Falco
1969-02-01
After a definition of hybrid calculation (combination of analogue and digital calculation) with a distinction between series and parallel hybrid computing, and a description of a hybrid computer structure and of task sharing between computers, this course proposes a description of hybrid hardware used in Saclay and Cadarache computing centres, and of operations performed by these systems. The next part addresses issues related to programming languages and software. The fourth part describes how a problem is organised for its processing on these computers. Methods of hybrid analysis are then addressed: resolution of optimisation problems, of partial differential equations, and of integral equations by means of different methods (gradient, maximum principle, characteristics, functional approximation, time slicing, Monte Carlo, Neumann iteration, Fischer iteration)
Calculation of projected ranges
International Nuclear Information System (INIS)
Biersack, J.P.
1980-09-01
The concept of multiple scattering is reconsidered for obtaining the directional spreading of ion motion as a function of energy loss. From this the mean projection of each pathlength element of the ion trajectory is derived which - upon summation or integration - leads to the desired mean projected range. In special cases, the calculation can be carried out analytically, otherwise a simple general algorithm is derived which is suitable even for the smallest programmable calculators. Necessary input for the present treatment consists only of generally accessable stopping power and straggling formulas. The procedure does not rely on scattering cross sections, e.g. power potential or f(t 1 sup(/) 2 ) approximations. The present approach lends itself easily to include electronic straggling or to treat composed target materials, or even to account for the so-called time integral. (orig.)
Spallation reactions: calculations
International Nuclear Information System (INIS)
Bertini, H.W.
1975-01-01
Current methods for calculating spallation reactions over various energy ranges are described and evaluated. Recent semiempirical fits to existing data will probably yield the most accurate predictions for these reactions in general. However, if the products in question have binding energies appreciably different from their isotropic neighbors and if the cross section is approximately 30 mb or larger, then the intranuclear-cascade-evaporation approach is probably better suited. (6 tables, 12 figures, 34 references) (U.S.)
Performance assessment calculational exercises
International Nuclear Information System (INIS)
Barnard, R.W.; Dockery, H.A.
1990-01-01
The Performance Assessment Calculational Exercises (PACE) are an ongoing effort coordinated by Yucca Mountain Project Office. The objectives of fiscal year 1990 work, termed PACE-90, as outlined in the Department of Energy Performance Assessment (PA) Implementation Plan were to develop PA capabilities among Yucca Mountain Project (YMP) participants by calculating performance of a Yucca Mountain (YM) repository under ''expected'' and also ''disturbed'' conditions, to identify critical elements and processes necessary to assess the performance of YM, and to perform sensitivity studies on key parameters. It was expected that the PACE problems would aid in development of conceptual models and eventual evaluation of site data. The PACE-90 participants calculated transport of a selected set of radionuclides through a portion of Yucca Mountain for a period of 100,000 years. Results include analyses of fluid-flow profiles, development of a source term for radionuclide release, and simulations of contaminant transport in the fluid-flow field. Later work included development of a problem definition for perturbations to the originally modeled conditions and for some parametric sensitivity studies. 3 refs
Cheng, Liang; Zhang, Yidong; Ji, Ming; Cui, Mantang; Zhang, Kai; Zhang, Minglei
2015-01-01
Given the increase in mining depth and intensity, tunnel failure as a result of rock burst has become an important issue in the field of mining engineering in China. Based on the Composite Rock-Bolt Bearing Structure, which is formed due to the interaction of the bolts driven into the surrounding rock, this paper analyzes a rock burst prevention mechanism, establishes a mechanical model in burst-prone ground, deduces the strength calculation formula of the Composite Rock-Bolt Bearing Structur...
Martins, Juliana R; Nunes, Francis M F; Cristino, Alexandre S; Simões, Zilá L P; Bitondi, Márcia M G
2010-03-26
Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. The hexamerin genes of the honey bee (hex 70a, hex 70b, hex 70c and hex 110) diverge considerably in structure, so that the overall amino acid identity shared among their deduced protein subunits varies from 30 to 42%. Bioinformatics search for motifs in the respective upstream control regions (UCRs) revealed six overrepresented motifs including a potential binding site for Ultraspiracle (Usp), a target of juvenile hormone (JH). The expression of these genes was induced by topical application of JH on worker larvae. The four genes are highly transcribed by the larval fat body, although with significant differences in transcript levels, but only hex 110 and hex 70a are re-induced in the adult fat body in a caste- and sex-specific fashion, workers showing the highest expression. Transcripts for hex 110, hex 70a and hex70b were detected in developing ovaries and testes, and hex 110 was highly transcribed in the ovaries of egg-laying queens. A phylogenetic analysis revealed that HEX 110 is located at the most basal position among the holometabola hexamerins, and like HEX 70a and HEX 70c, it shares potential orthology relationship with hexamerins from other hymenopteran species. Striking differences were found in the structure and developmental expression of the four hexamerin genes in the honey bee. The presence of a potential binding site for Usp in the respective 5' UCRs, and the results of experiments on JH level manipulation in vivo support the hypothesis of regulation by JH. Transcript levels and patterns in the fat body and gonads suggest that, in addition to their primary
Directory of Open Access Journals (Sweden)
Martins Juliana R
2010-03-01
Full Text Available Abstract Background Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. Results The hexamerin genes of the honey bee (hex 70a, hex 70b, hex 70c and hex 110 diverge considerably in structure, so that the overall amino acid identity shared among their deduced protein subunits varies from 30 to 42%. Bioinformatics search for motifs in the respective upstream control regions (UCRs revealed six overrepresented motifs including a potential binding site for Ultraspiracle (Usp, a target of juvenile hormone (JH. The expression of these genes was induced by topical application of JH on worker larvae. The four genes are highly transcribed by the larval fat body, although with significant differences in transcript levels, but only hex 110 and hex 70a are re-induced in the adult fat body in a caste- and sex-specific fashion, workers showing the highest expression. Transcripts for hex 110, hex 70a and hex70b were detected in developing ovaries and testes, and hex 110 was highly transcribed in the ovaries of egg-laying queens. A phylogenetic analysis revealed that HEX 110 is located at the most basal position among the holometabola hexamerins, and like HEX 70a and HEX 70c, it shares potential orthology relationship with hexamerins from other hymenopteran species. Conclusions Striking differences were found in the structure and developmental expression of the four hexamerin genes in the honey bee. The presence of a potential binding site for Usp in the respective 5' UCRs, and the results of experiments on JH level manipulation in vivo support the hypothesis of regulation by JH. Transcript levels and patterns in the fat body
2010-01-01
Background Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. Results The hexamerin genes of the honey bee (hex 70a, hex 70b, hex 70c and hex 110) diverge considerably in structure, so that the overall amino acid identity shared among their deduced protein subunits varies from 30 to 42%. Bioinformatics search for motifs in the respective upstream control regions (UCRs) revealed six overrepresented motifs including a potential binding site for Ultraspiracle (Usp), a target of juvenile hormone (JH). The expression of these genes was induced by topical application of JH on worker larvae. The four genes are highly transcribed by the larval fat body, although with significant differences in transcript levels, but only hex 110 and hex 70a are re-induced in the adult fat body in a caste- and sex-specific fashion, workers showing the highest expression. Transcripts for hex 110, hex 70a and hex70b were detected in developing ovaries and testes, and hex 110 was highly transcribed in the ovaries of egg-laying queens. A phylogenetic analysis revealed that HEX 110 is located at the most basal position among the holometabola hexamerins, and like HEX 70a and HEX 70c, it shares potential orthology relationship with hexamerins from other hymenopteran species. Conclusions Striking differences were found in the structure and developmental expression of the four hexamerin genes in the honey bee. The presence of a potential binding site for Usp in the respective 5' UCRs, and the results of experiments on JH level manipulation in vivo support the hypothesis of regulation by JH. Transcript levels and patterns in the fat body and gonads suggest that
Accurate quantum chemical calculations
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
1989-01-01
An important goal of quantum chemical calculations is to provide an understanding of chemical bonding and molecular electronic structure. A second goal, the prediction of energy differences to chemical accuracy, has been much harder to attain. First, the computational resources required to achieve such accuracy are very large, and second, it is not straightforward to demonstrate that an apparently accurate result, in terms of agreement with experiment, does not result from a cancellation of errors. Recent advances in electronic structure methodology, coupled with the power of vector supercomputers, have made it possible to solve a number of electronic structure problems exactly using the full configuration interaction (FCI) method within a subspace of the complete Hilbert space. These exact results can be used to benchmark approximate techniques that are applicable to a wider range of chemical and physical problems. The methodology of many-electron quantum chemistry is reviewed. Methods are considered in detail for performing FCI calculations. The application of FCI methods to several three-electron problems in molecular physics are discussed. A number of benchmark applications of FCI wave functions are described. Atomic basis sets and the development of improved methods for handling very large basis sets are discussed: these are then applied to a number of chemical and spectroscopic problems; to transition metals; and to problems involving potential energy surfaces. Although the experiences described give considerable grounds for optimism about the general ability to perform accurate calculations, there are several problems that have proved less tractable, at least with current computer resources, and these and possible solutions are discussed.
Zero Temperature Hope Calculations
International Nuclear Information System (INIS)
Rozsnyai, B. F.
2002-01-01
The primary purpose of the HOPE code is to calculate opacities over a wide temperature and density range. It can also produce equation of state (EOS) data. Since the experimental data at the high temperature region are scarce, comparisons of predictions with the ample zero temperature data provide a valuable physics check of the code. In this report we show a selected few examples across the periodic table. Below we give a brief general information about the physics of the HOPE code. The HOPE code is an ''average atom'' (AA) Dirac-Slater self-consistent code. The AA label in the case of finite temperature means that the one-electron levels are populated according to the Fermi statistics, at zero temperature it means that the ''aufbau'' principle works, i.e. no a priory electronic configuration is set, although it can be done. As such, it is a one-particle model (any Hartree-Fock model is a one particle model). The code is an ''ion-sphere'' model, meaning that the atom under investigation is neutral within the ion-sphere radius. Furthermore, the boundary conditions for the bound states are also set at the ion-sphere radius, which distinguishes the code from the INFERNO, OPAL and STA codes. Once the self-consistent AA state is obtained, the code proceeds to generate many-electron configurations and proceeds to calculate photoabsorption in the ''detailed configuration accounting'' (DCA) scheme. However, this last feature is meaningless at zero temperature. There is one important feature in the HOPE code which should be noted; any self-consistent model is self-consistent in the space of the occupied orbitals. The unoccupied orbitals, where electrons are lifted via photoexcitation, are unphysical. The rigorous way to deal with that problem is to carry out complete self-consistent calculations both in the initial and final states connecting photoexcitations, an enormous computational task. The Amaldi correction is an attempt to address this problem by distorting the
International Nuclear Information System (INIS)
Heilbron Filho, P.F.L.; Oliveira Brandao, R. de.
1988-04-01
The theory of Point Kernel applied to a source uniformelly distributed in a cylindrical geometry was utilized to estimated the Cs-137 content of each package of radioactive waste collected. The Taylor equation was employed to calculate the build-up factor and the Green function G was adjusted by means of a least square method. The theory also takes into account factors such as aditional shielding, heterogeneity and humidity of the medium as well as associated uncertanties of the parameters envolved. (author) [pt
Calculations in furnace technology
Davies, Clive; Hopkins, DW; Owen, WS
2013-01-01
Calculations in Furnace Technology presents the theoretical and practical aspects of furnace technology. This book provides information pertinent to the development, application, and efficiency of furnace technology. Organized into eight chapters, this book begins with an overview of the exothermic reactions that occur when carbon, hydrogen, and sulfur are burned to release the energy available in the fuel. This text then evaluates the efficiencies to measure the quantity of fuel used, of flue gases leaving the plant, of air entering, and the heat lost to the surroundings. Other chapters consi
International Nuclear Information System (INIS)
Thompson, W.L.; Deutsch, O.L.; Booth, T.E.
1980-04-01
Several Monte Carlo techniques are compared in the transport of neutrons of different source energies through two different deep-penetration problems each with two parts. The first problem involves transmission through a 200-cm concrete slab. The second problem is a 90 0 bent pipe jacketed by concrete. In one case the pipe is void, and in the other it is filled with liquid sodium. Calculations are made with two different Los Alamos Monte Carlo codes: the continuous-energy code MCNP and the multigroup code MCMG
Bae, Chae-Wun; Lee, Joong-Bok; Park, Seung-Yong; Song, Chang-Seon; Lee, Nak-Hyung; Seo, Kun-Ho; Kang, Young-Sun; Park, Choi-Kyu; Choi, In-Soo
2013-08-01
Canine distemper virus (CDV) causes highly contagious respiratory, gastrointestinal, and neurological diseases in wild and domestic animal species. Despite a broad vaccination campaign, the disease is still a serious problem worldwide. In this study, six field CDV strains were isolated from three dogs, two raccoon dogs, and one badger in Korea. The full sequence of the genes encoding fusion (F) and hemagglutinin (H) proteins were compared with those of other CDVs including field and vaccine strains. The phylogenetic analysis for the F and H genes indicated that the two CDV strains isolated from dogs were most closely related to Chinese strains in the Asia-1 genotype. Another four strains were closely related to Japanese strains in the Asia-2 genotype. The six currently isolated strains shared 90.2-92.1% and 88.2-91.8% identities with eight commercial vaccine strains in their nucleotide and amino acid sequences of the F protein, respectively. They also showed 90.1-91.4% and 87.8-90.7% identities with the same vaccine strains in their nucleotide and deduced amino acid sequences of the H protein, respectively. Different N-linked glycosylation sites were identified in the F and H genes of the six isolates from the prototype vaccine strain Onderstepoort. Collectively, these results demonstrate that at least two different CDV genotypes currently exist in Korea. The considerable genetic differences between the vaccine strains and wild-type isolates would be a major factor of the incomplete protection of dogs from CDV infections.
Directory of Open Access Journals (Sweden)
F.H.R. Fagundes
2010-03-01
Full Text Available To illustrate the construction of precursor complementary DNAs, we isolated mRNAs from whole venom samples. After reverse transcription polymerase chain reaction (RT-PCR, we amplified the cDNA coding for a neurotoxic protein, phospholipase A2 D49 (PLA2 D49, from the venom of Crotalus durissus collilineatus (Cdc PLA2. The cDNA encoding Cdc PLA2 from whole venom was sequenced. The deduced amino acid sequence of this cDNA has high overall sequence identity with the group II PLA2 protein family. Cdc PLA2 has 14 cysteine residues capable of forming seven disulfide bonds that characterize this group of PLA2 enzymes. Cdc PLA2 was isolated using conventional Sephadex G75 column chromatography and reverse-phase high performance liquid chromatography (RP-HPLC. The molecular mass was estimated using matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF mass spectrometry. We tested the neuromuscular blocking activities on chick biventer cervicis neuromuscular tissue. Phylogenetic analysis of Cdc PLA2 showed the existence of two lines of N6-PLA2, denominated F24 and S24. Apparently, the sequences of the New World’s N6-F24-PLA2 are similar to those of the agkistrodotoxin from the Asian genus Gloydius. The sequences of N6-S24-PLA2 are similar to the sequence of trimucrotoxin from the genus Protobothrops, found in the Old World.
Thomas, Louise; Hodgson, David A; Wentzel, Alexander; Nieselt, Kay; Ellingsen, Trond E; Moore, Jonathan; Morrissey, Edward R; Legaie, Roxane; Wohlleben, Wolfgang; Rodríguez-García, Antonio; Martín, Juan F; Burroughs, Nigel J; Wellington, Elizabeth M H; Smith, Margaret C M
2012-02-01
Bacteria in the genus Streptomyces are soil-dwelling oligotrophs and important producers of secondary metabolites. Previously, we showed that global messenger RNA expression was subject to a series of metabolic and regulatory switches during the lifetime of a fermentor batch culture of Streptomyces coelicolor M145. Here we analyze the proteome from eight time points from the same fermentor culture and, because phosphate availability is an important regulator of secondary metabolite production, compare this to the proteome of a similar time course from an S. coelicolor mutant, INB201 (ΔphoP), defective in the control of phosphate utilization. The proteomes provide a detailed view of enzymes involved in central carbon and nitrogen metabolism. Trends in protein expression over the time courses were deduced from a protein abundance index, which also revealed the importance of stress pathway proteins in both cultures. As expected, the ΔphoP mutant was deficient in expression of PhoP-dependent genes, and several putatively compensatory metabolic and regulatory pathways for phosphate scavenging were detected. Notably there is a succession of switches that coordinately induce the production of enzymes for five different secondary metabolite biosynthesis pathways over the course of the batch cultures.
Park, Jaeheung; Martinis, Carlos R.; Luehr, Hermann; Pfaff, Robert F.; Kwak, Young-Sil
2016-01-01
Transitions from depletions to enhancements of 630.0 nm nighttime airglow have been observed at Arecibo. Numerical simulations by Krall et al. (2009) predicted that they should occur only in one hemisphere, which has not yet been confirmed observationally. In this study we investigate the hemispheric conjugacy of the depletion-to-enhancement transition using multiple instruments. We focus on one event observed in the American longitude sector on 22 December 2014: 630.0 nm airglow depletions evolved into enhancements in the Northern Hemisphere while the evolution did not occur in the conjugate location in the Southern Hemisphere. Concurrent plasma density measured by low Earth orbit (LEO) satellites and 777.4 nm airglow images support that the depletions and enhancements of 630.0 nm night time airglow reflect plasma density decreases and increases (blobs), respectively. Characteristics of the airglow depletions, in the context of the LEO satellite data, further suggest that the plasma density depletion deduced from the airglow data represents equatorial plasma bubbles (EPBs) rather than medium-scale traveling ionospheric disturbances from midlatitudes. Hence, the event in this study can be interpreted as EPB-to-blob transition.
Pérez, Ana G; de la Rosa, Raúl; Pascual, Mar; Sánchez-Ortiz, Araceli; Romero-Segura, Carmen; León, Lorenzo; Sanz, Carlos
2016-01-08
Volatile compounds are responsible for most of the sensory qualities of virgin olive oil and they are synthesized when enzymes and substrates come together as olive fruit is crushed during the industrial process to obtain the oil. Here we have studied the variability among the major volatile compounds in virgin olive oil prepared from the progeny of a cross of Picual and Arbequina olive cultivars (Olea europaea L.). The volatile compounds were isolated by SPME, and analyzed by HRGC-MS and HRGC-FID. Most of the volatile compounds found in the progeny's oil are produced by the enzymes in the so-called lipoxygenase pathway, and they may be clustered into different groups according to their chain length and polyunsaturated fatty acid origin (linoleic and linolenic acids). In addition, a group of compounds derived from amino acid metabolism and two terpenes also contributed significantly to the volatile fraction, some of which had significant odor values in most of the genotypes evaluated. The volatile compound content of the progeny was very varied, widely transgressing the progenitor levels, suggesting that in breeding programs it might be more effective to consider a larger number of individuals within the same cross than using different crosses with fewer individuals. Multivariate analysis allowed genotypes with particularly interesting volatile compositions to be identified and their flavor quality deduced. Copyright © 2015 Elsevier B.V. All rights reserved.
Weldon Spring dose calculations
International Nuclear Information System (INIS)
Dickson, H.W.; Hill, G.S.; Perdue, P.T.
1978-09-01
In response to a request by the Oak Ridge Operations (ORO) Office of the Department of Energy (DOE) for assistance to the Department of the Army (DA) on the decommissioning of the Weldon Spring Chemical Plant, the Health and Safety Research Division of the Oak Ridge National Laboratory (ORNL) performed limited dose assessment calculations for that site. Based upon radiological measurements from a number of soil samples analyzed by ORNL and from previously acquired radiological data for the Weldon Spring site, source terms were derived to calculate radiation doses for three specific site scenarios. These three hypothetical scenarios are: a wildlife refuge for hunting, fishing, and general outdoor recreation; a school with 40 hr per week occupancy by students and a custodian; and a truck farm producing fruits, vegetables, meat, and dairy products which may be consumed on site. Radiation doses are reported for each of these scenarios both for measured uranium daughter equilibrium ratios and for assumed secular equilibrium. Doses are lower for the nonequilibrium case
Configuration space Faddeev calculations
International Nuclear Information System (INIS)
Payne, G.L.; Klink, W.H.; Polyzou, W.N.
1989-01-01
The detailed study of few-body systems provides one of the most effective means for studying nuclear physics at subnucleon distance scales. For few-body systems the model equations can be solved numerically with errors less than the experimental uncertainties. We have used such systems to investigate the size of relativistic effects, the role of meson-exchange currents, and the importance of quark degrees of freedom in the nucleus. Complete calculations for momentum-dependent potentials have been performed, and the properties of the three-body bound state for these potentials have been studied. Few-body calculations of the electromagnetic form factors of the deuteron and pion have been carried out using a front-form formulation of relativistic quantum mechanics. The decomposition of the operators transforming convariantly under the Poincare group into kinematical and dynamical parts has been studies. New ways for constructing interactions between particles, as well as interactions which lead to the production of particles, have been constructed in the context of a relativistic quantum mechanics. To compute scattering amplitudes in a nonperturbative way, classes of operators have been generated out of which the phase operator may be constructed. Finally, we have worked out procedures for computing Clebsch-Gordan and Racah coefficients on a computer, as well as giving procedures for dealing with the multiplicity problem
International Nuclear Information System (INIS)
Penner, J.E.; Haselman, L.C.; Edwards, L.L.
1985-01-01
Smoke from raging fires produced in the aftermath of a major nuclear exchange has been predicted to cause large decreases in surface temperatures. However, the extent of the decrease and even the sign of the temperature change, depend on how the smoke is distributed with altitude. We present a model capable of evaluating the initial distribution of lofted smoke above a massive fire. Calculations are shown for a two-dimensional slab version of the model and a full three-dimensional version. The model has been evaluated by simulating smoke heights for the Hamburg firestorm of 1943 and a smaller scale oil fire which occurred in Long Beach in 1958. Our plume heights for these fires are compared to those predicted by the classical Morton-Taylor-Turner theory for weakly buoyant plumes. We consider the effect of the added buoyancy caused by condensation of water-laden ground level air being carried to high altitude with the convection column as well as the effects of background wind on the calculated smoke plume heights for several fire intensities. We find that the rise height of the plume depends on the assumed background atmospheric conditions as well as the fire intensity. Little smoke is injected into the stratosphere unless the fire is unusually intense, or atmospheric conditions are more unstable than we have assumed. For intense fires significant amounts of water vapor are condensed raising the possibility of early scavenging of smoke particles by precipitation. 26 references, 11 figures
Shielding calculations for NET
International Nuclear Information System (INIS)
Verschuur, K.A.; Hogenbirk, A.
1991-05-01
In the European Fusion Technology Programme there is only a small activity on research and development for fusion neutronics. Never-the-less, looking further than blanket design now, as ECN is getting involved in design of radiation shields for the coils and biological shields, it becomes apparent that fusion neutronics as a whole still needs substantial development. Existing exact codes for calculation of complex geometries like MCNP and DORT/TORT are put over the limits of their numerical capabilities, whilst approximate codes for complex geometries like FURNACE and MERCURE4 are put over the limits of their modelling capabilities. The main objective of this study is just to find out how far we can get with existing codes in obtaining reliable values for the radiation levels inside and outside the cryostat/shield during operation and after shut-down. Starting with a 1D torus model for preliminary parametric studies, more dimensional approximation of the torus or parts of it including the main heterogeneities should follow. Regular contacts with the NET-Team are kept, to be aware of main changes in NET design that might affect our calculation models. Work on the contract started 1 July 1990. The technical description of the contract is given. (author). 14 refs.; 4 figs.; 1 tab
Starck, Patricia L; Love, Karen; McPherson, Robert
2008-01-01
In recent years, the focus has been on increasing the number of registered nurse (RN) graduates. Numerous states have initiated programs to increase the number and quality of students entering nursing programs, and to expand the capacity of their programs to enroll additional qualified students. However, little attention has been focused on an equally, if not more, effective method for increasing the number of RNs produced-increasing the graduation rate of students enrolling. This article describes a project that undertook the task of compiling graduation data for 15 entry-level programs, standardizing terms and calculations for compiling the data, and producing a regional report on graduation rates of RN students overall and by type of program. Methodology is outlined in this article. This effort produced results that were surprising to program deans and directors and is expected to produce greater collaborative efforts to improve these rates both locally and statewide.
Kheifets, Aaron; Gallistel, C R
2012-05-29
Animals successfully navigate the world despite having only incomplete information about behaviorally important contingencies. It is an open question to what degree this behavior is driven by estimates of stochastic parameters (brain-constructed models of the experienced world) and to what degree it is directed by reinforcement-driven processes that optimize behavior in the limit without estimating stochastic parameters (model-free adaptation processes, such as associative learning). We find that mice adjust their behavior in response to a change in probability more quickly and abruptly than can be explained by differential reinforcement. Our results imply that mice represent probabilities and perform calculations over them to optimize their behavior, even when the optimization produces negligible material gain.
Smile esthetics: calculated beauty?
Lecocq, Guillaume; Truong Tan Trung, Lisa
2014-06-01
Esthetic demand from patients continues to increase. Consequently, the treatments we offer are moving towards more discreet or invisible techniques using lingual brackets in order to achieve harmonious, balanced results in line with our treatment goals. As orthodontists, we act upon relationships between teeth and bone. And the equilibrium they create impacts the entire face via the smile. A balanced smile is essential to an esthetic outcome and is governed by rules, which guide both the practitioner and patient. A smile can be described in terms of mathematical ratios and proportions but beauty cannot be calculated. For the smile to sit harmoniously within the face, we need to take into account facial proportions and the possibility of their being modified by our orthopedic appliances or by surgery. Copyright © 2014 CEO. Published by Elsevier Masson SAS. All rights reserved.
Selim, El Sayed Ibrahim
2016-01-01
The Sinai Peninsula is a part of the Sinai sub-plate that located between the southeast Nubian-Arabian shield and the southeastern Mediterranean northward. The main objectives of this investigation are to deduce the main sedimentary basin and its subdivisions, identify the subsurface structural framework that affects the study area and determine the thickness of sedimentary cover of the basement surface. The total intensity magnetic map, Bouguer gravity map and seismic data were used to achieve the study aims. Structural interpretation of the gravity and magnetic data were done by applying advanced processing techniques. These techniques include; Reduce to the pole (RTP), Power spectrum, Tile derivative and Analytical Signal techniques were applied on gravity and magnetic data. Two dimensional gravity and magnetic modeling and interpretation of seismic sections were done to determine the thickness of sedimentary cover of the study area. The integration of our interpretation suggests that, the northern Sinai area consists of elongated troughs that contain many high structural trends. Four major structural trends have been identified, that, reflecting the influence of district regional tectonic movements. These trends are: (1) NE-SW trend; (2) NNW-SSE trend; (3) ENE-WSW trend and (4) WNW-ESE trend. There are also many minor trends, E-W, NW-SE and N-S structural trends. The main sedimentary basin of North Sinai is divided into four sub-basins; (1) Northern Maghara; (2) Northeastern Sinai; (3) Northwestern Sinai and (4) Central Sinai basin. The sedimentary cover ranges between 2 km and 7 km in the northern part of the study area.
Relative Hazard Calculation Methodology
International Nuclear Information System (INIS)
DL Strenge; MK White; RD Stenner; WB Andrews
1999-01-01
The methodology presented in this document was developed to provide a means of calculating the RH ratios to use in developing useful graphic illustrations. The RH equation, as presented in this methodology, is primarily a collection of key factors relevant to understanding the hazards and risks associated with projected risk management activities. The RH equation has the potential for much broader application than generating risk profiles. For example, it can be used to compare one risk management activity with another, instead of just comparing it to a fixed baseline as was done for the risk profiles. If the appropriate source term data are available, it could be used in its non-ratio form to estimate absolute values of the associated hazards. These estimated values of hazard could then be examined to help understand which risk management activities are addressing the higher hazard conditions at a site. Graphics could be generated from these absolute hazard values to compare high-hazard conditions. If the RH equation is used in this manner, care must be taken to specifically define and qualify the estimated absolute hazard values (e.g., identify which factors were considered and which ones tended to drive the hazard estimation)
Experimental Young's modulus calculations
International Nuclear Information System (INIS)
Chen, Y.; Jayakumar, R.; Yu, K.
1994-01-01
Coil is a very important magnet component. The turn location and the coil size impact both mechanical and magnetic behavior of the magnet. The Young's modulus plays a significant role in determining the coil location and size. Therefore, Young's modulus study is essential in predicting both the analytical and practical magnet behavior. To determine the coil Young's modulus, an experiment has been conducted to measure azimuthal sizes of a half quadrant QSE101 inner coil under different loading. All measurements are made at four different positions along an 8-inch long inner coil. Each measurement is repeated three times to determine the reproducibility of the experiment. To ensure the reliability of this experiment, the same measurement is performed twice with a open-quotes dummy coil,close quotes which is made of G10 and has the same dimension and similar azimuthal Young's modulus as the inner coil. The difference between the G10 azimuthal Young's modulus calculated from the experiments and its known value from the manufacturer will be compared. Much effort has been extended in analyzing the experimental data to obtain a more reliable Young's modulus. Analysis methods include the error analysis method and the least square method
Relativistic few body calculations
International Nuclear Information System (INIS)
Gross, F.
1988-01-01
A modern treatment of the nuclear few-body problem must take into account both the quark structure of baryons and mesons, which should be important at short range, and the relativistic exchange of mesons, which describes the long range, peripheral interactions. A way to model both of these aspects is described. The long range, peripheral interactions are calculated using the spectator model, a general approach in which the spectators to nucleon interactions are put on their mass-shell. Recent numerical results for a relativistic OBE model of the NN interaction, obtained by solving a relativistic equation with one-particle on mass-shell, will be presented and discussed. Two meson exchange models, one with only four mesons (π,σ,/rho/,ω) but with a 25% admixture of γ 5 coupling for the pion, and a second with six mesons (π,σ,/rho/,ω,δ,/eta/) but pure γ 5 γ/sup μ/ pion coupling, are shown to give very good quantitative fits to the NN scattering phase shifts below 400 MeV, and also a good description of the /rvec p/ 40 Ca elastic scattering observables. Applications of this model to electromagnetic interactions of the two body system, with emphasis on the determination of relativistic current operators consistent with the dynamics and the exact treatment of current conservation in the presence of phenomenological form factors, will be described. 18 refs., 8 figs
Equilibrium calculations, ch. 6
International Nuclear Information System (INIS)
Deursen, A.P.J. van
1976-01-01
A calculation is presented of dimer intensities obtained in supersonic expansions. There are two possible limiting considerations; the dimers observed are already present in the source, in thermodynamic equilibrium, and are accelerated in the expansion. Destruction during acceleration is neglected, as are processes leading to newly formed dimers. On the other hand one can apply a kinetic approach, where formation and destruction processes are followed throughout the expansion. The difficulty of this approach stems from the fact that the density, temperature and rate constants have to be known at all distances from the nozzle. The simple point of view has been adopted and the measured dimer intensities are compared with the equilibrium concentration in the source. The comparison is performed under the assumption that the detection efficiency for dimers is twice the detection efficiency for monomers. The experimental evidence against the simple point of view that the dimers of the onset region are formed in the source already, under equilibrium conditions, is discussed. (Auth.)
Configuration space Faddeev calculations
International Nuclear Information System (INIS)
Payne, G.L.; Klink, W.H.; Ployzou, W.N.
1991-01-01
The detailed study of few-body systems provides one of the most precise tools for studying the dynamics of nuclei. Our research program consists of a careful theoretical study of the nuclear few-body systems. During the past year we have completed several aspects of this program. We have continued our program of using the trinucleon system to investigate the validity of various realistic nucleon-nucleon potentials. Also, the effects of meson-exchange currents in nuclear systems have been studied. Initial calculations using the configuration-space Faddeev equations for nucleon-deuteron scattering have been completed. With modifications to treat relativistic systems, few-body methods can be applied to phenomena that are sensitive to the structure of the individual hadrons. We have completed a review of Relativistic Hamiltonian Dynamics in Nuclear and Particle Physics for Advances in Nuclear Physics. Although it is called a review, it is a large document that contains a significant amount of new research
Excitation of giant resonances via charge exchange reactions
International Nuclear Information System (INIS)
Goodman, C.D.
1979-01-01
Charge-exchange reactions can be useful for identifying isovector resonances. At present the most promising use of charge-exchange reactions with respect to giant resonances is to locate and study Gamow-Teller (GT) resonances. Detailed comparisons between GT and M1 strengths can yield further structure information. 7 figures
Nuclear structure information from nucleon-nucleus scattering experiments at TRIUMF
International Nuclear Information System (INIS)
Haeusser, O.
1989-02-01
We discuss a variety of forward-angle measurements of cross sections for (n,p), (p,p') and (p,n) reactions which were carried out using the medium-resolution spectrometer (MRS) at TRIUMF. The ratio of L=0 isovector spinflip cross section and Gamow-Teller strength has been investigated at 200-450 MeV for several strong transitions of known B(GT) in p-shell nuclei. Isospin symmetry in N-nucleus reactions has been tested for Gamow-Teller transitions to isospin triads in A=6 and A=12 nuclei. The prospects of identifying orbital and meson exchange current contributions in M1 transitions from a state-by-state comparison of M1 and Gamow-Teller strength in sd shell nuclei are discussed. Finally we describe a test of the Gamow-Teller sum rule in 54 Fe where both S - and S + strength are substantial and have been extracted from a multipole decomposition of (p,n) and (n,p) angular distributions
Charge exchange probes of nuclear structure and interactions with emphasis on (p,n)
International Nuclear Information System (INIS)
Goodman, C.D.
1980-01-01
New results from (p,n) studies at IUCF show that it is possible to observe Gamow-Teller (GT) strength and extract GT matrix elements from (p,n) measurements. The charge exchange reactions ( 6 Li, 6 He) and (π + ,π 0 ) involve different projectile quantum numbers, and the relationships of these reactions to (p,n) is discussed
Searches for exotic interactions in nuclear beta decay
Energy Technology Data Exchange (ETDEWEB)
Naviliat-Cuncic, O. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, 640 S Shaw Lane, East Lansing MI 48824 (United States)
2016-07-07
This contribution presents current efforts in the search for exotic interactions in nuclear β decay using a calorimetric technique for the measurement of the β energy spectrum shape. We describe the criteria for the choice of sensitive candidates in Gamow-Teller transitions and present the status of measurements performed in {sup 6}He and {sup 20}F decay.
Prof. Ikeda’s important contributions to nuclear physics
Brink, D M
2010-01-01
Professor Ikeda has made many fundamental contributions to nuclear physics, especially to the theory of Gamow-Teller giant resonances, to nuclear cluster physics, to hypernuclear physics, and to the physics of neutron-rich nuclei. He also has played an important role in the education of young researchers in Japan and on the contacts between theoreticians and experimentalists.
Configuration mixing for spin-isospin modes
International Nuclear Information System (INIS)
Ichimura, Munetake
2005-01-01
Development of theories of configuration mixing is reviewed, concentrating on their application to spin-isospin modes, especially to the Gamow-Teller transitions. This talk is divided into three historical stages, the first order configuration mixing as the first stage, the second order configuration mixing as the second stage, and the delta-isobar-hole mixing as the third stage
The rating reliability calculator
Directory of Open Access Journals (Sweden)
Solomon David J
2004-04-01
Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.
International Nuclear Information System (INIS)
Rhoades, W.A.; Childs, R.L.; Ingersoll, D.T.
1988-01-01
The analysis of radiation doses received during the World War II attack on Nagasaki provides an important source of biochemical information. More than 40 years after the war, it has been possible to make a satisfactory calculation of the doses to personnel inside reinforced concrete buildings by use of a 3-dimensional discrete ordinates code, TORT. The results were used to deduce a new value of the LD50 parameter that is in good agreement with traditional values. The new discrete ordinates software appears to have potential application to conventional radiation transport calculations as well. 9 refs., 3 figs., 2 tabs
MOx Depletion Calculation Benchmark
International Nuclear Information System (INIS)
San Felice, Laurence; Eschbach, Romain; Dewi Syarifah, Ratna; Maryam, Seif-Eddine; Hesketh, Kevin
2016-01-01
Under the auspices of the NEA Nuclear Science Committee (NSC), the Working Party on Scientific Issues of Reactor Systems (WPRS) has been established to study the reactor physics, fuel performance, radiation transport and shielding, and the uncertainties associated with modelling of these phenomena in present and future nuclear power systems. The WPRS has different expert groups to cover a wide range of scientific issues in these fields. The Expert Group on Reactor Physics and Advanced Nuclear Systems (EGRPANS) was created in 2011 to perform specific tasks associated with reactor physics aspects of present and future nuclear power systems. EGRPANS provides expert advice to the WPRS and the nuclear community on the development needs (data and methods, validation experiments, scenario studies) for different reactor systems and also provides specific technical information regarding: core reactivity characteristics, including fuel depletion effects; core power/flux distributions; Core dynamics and reactivity control. In 2013 EGRPANS published a report that investigated fuel depletion effects in a Pressurised Water Reactor (PWR). This was entitled 'International Comparison of a Depletion Calculation Benchmark on Fuel Cycle Issues' NEA/NSC/DOC(2013) that documented a benchmark exercise for UO 2 fuel rods. This report documents a complementary benchmark exercise that focused on PuO 2 /UO 2 Mixed Oxide (MOX) fuel rods. The results are especially relevant to the back-end of the fuel cycle, including irradiated fuel transport, reprocessing, interim storage and waste repository. Saint-Laurent B1 (SLB1) was the first French reactor to use MOx assemblies. SLB1 is a 900 MWe PWR, with 30% MOx fuel loading. The standard MOx assemblies, used in Saint-Laurent B1 reactor, include three zones with different plutonium enrichments, high Pu content (5.64%) in the center zone, medium Pu content (4.42%) in the intermediate zone and low Pu content (2.91%) in the peripheral zone
Developments for the 6He beta - nu angular correlation experiment
Zumwalt, David W.
This thesis describes developments toward the measurement of the angular correlation between the beta and the antineutrino in the beta decay of 6He. This decay is a pure Gamow-Teller decay which is described in the Standard Model as a purely axial vector weak interaction. The angular correlation is characterized by the parameter abetanu = -1/3 in the Standard Model. Any deviation from this value would be evidence for tensor components in the weak interaction and would constitute new physics. A new method will be used to measure the parameter a betanu from 6He decays, featuring a magneto-optical trap that will measure the beta particle in coincidence with the recoiling 6Li daughter ion. This neutral atom trapping scheme provides cold, tightly confined atoms which will reduce systematic uncertainties related to the initial position of the decay. By knowing the initial position of the decay and measuring the time of flight of the recoiling 6Li daughter ion in coincidence with the beta, the angular correlation between the beta and the antineutrino can be deduced. We aim to measure a betanu first to the level of 1%, and eventually to the 0.1% level, which would represent an order of magnitude improvement in precision over past experiments. Towards this goal, we have designed, built, and successfully tested a liquid lithium target to provide >2×10. {10} 6He atoms/sto a low-background environment, which is the most intense source of 6He presently available. This allowed for an additional measurement of the 6He half-life (806.89 +/- 0.11stat +0.23-0.19syst ms) to be made with unprecedented precision, resolving discrepancies in past measurements. We have also tested our trapping and detection apparatus and have begun to record preliminary coincidence events.
ENRAF gauge reference level calculations
Energy Technology Data Exchange (ETDEWEB)
Huber, J.H., Fluor Daniel Hanford
1997-02-06
This document describes the method for calculating reference levels for Enraf Series 854 Level Detectors as installed in the tank farms. The reference level calculation for each installed level gauge is contained herein.
HEU benchmark calculations and LEU preliminary calculations for IRR-1
International Nuclear Information System (INIS)
Caner, M.; Shapira, M.; Bettan, M.; Nagler, A.; Gilat, J.
2004-01-01
We performed neutronics calculations for the Soreq Research Reactor, IRR-1. The calculations were done for the purpose of upgrading and benchmarking our codes and methods. The codes used were mainly WIMS-D/4 for cell calculations and the three dimensional diffusion code CITATION for full core calculations. The experimental flux was obtained by gold wire activation methods and compared with our calculated flux profile. The IRR-1 is loaded with highly enriched uranium fuel assemblies, of the plate type. In the framework of preparation for conversion to low enrichment fuel, additional calculations were done assuming the presence of LEU fresh fuel. In these preliminary calculations we investigated the effect on the criticality and flux distributions of the increase of U-238 loading, and the corresponding uranium density.(author)
MCNP and OMEGA criticality calculations
International Nuclear Information System (INIS)
Seifert, E.
1998-04-01
The reliability of OMEGA criticality calculations is shown by a comparison with calculations by the validated and widely used Monte Carlo code MCNP. The criticality of 16 assemblies with uranium as fissionable is calculated with the codes MCNP (Version 4A, ENDF/B-V cross sections), MCNP (Version 4B, ENDF/B-VI cross sections), and OMEGA. Identical calculation models are used for the three codes. The results are compared mutually and with the experimental criticality of the assemblies. (orig.)
CALCULATION OF LASER CUTTING COSTS
Bogdan Nedic; Milan Eric; Marijana Aleksijevic
2016-01-01
The paper presents description methods of metal cutting and calculation of treatment costs based on model that is developed on Faculty of mechanical engineering in Kragujevac. Based on systematization and analysis of large number of calculation models of cutting with unconventional methods, mathematical model is derived, which is used for creating a software for calculation costs of metal cutting. Software solution enables resolving the problem of calculating the cost of laser cutting, compar...
Transient anisotropic magnetic field calculation
International Nuclear Information System (INIS)
Jesenik, Marko; Gorican, Viktor; Trlep, Mladen; Hamler, Anton; Stumberger, Bojan
2006-01-01
For anisotropic magnetic material, nonlinear magnetic characteristics of the material are described with magnetization curves for different magnetization directions. The paper presents transient finite element calculation of the magnetic field in the anisotropic magnetic material based on the measured magnetization curves for different magnetization directions. For the verification of the calculation method some results of the calculation are compared with the measurement
Application of the CRAY-1 for quantum chemistry calculations
International Nuclear Information System (INIS)
Saunders, V.R.; Guest, M.F.
1982-01-01
The following steps in a typical quantum chemistry calculation will be considered: 1. Gaussian integrals evaluation. 2. Hartree-Fock computation of an uncorrelated wavefunction. 3. 4-index transformation of two-electron integrals. 4. Configuration interaction calculations of a correlated wavefunction. In all the above steps we have found that algorithms may be devised which formulate the problem as being dominated by a series of matrix multiplications: R=AB, where A (or B) is sparse. A routine for performing the sparse matrix multiply has been prepared with a maximum measured performance of 147 M flops. When this routine is used in our applications packages, overall performance of approximately 50, 100 and 120 M flops are observed for steps 1, 3 and 4, respectively. The result in step 2 is not so successful, as effective implementation of the matrix multiplication requires efficient performance of data gather and scatter sequences (not vectorisable on the CRAY-1), and a performance of 10 M flops is observed. The importance of gather/scatter sequences in such operations as file sorting is pointed out. The present performance is compared with that previously obtained on CDC 7600 equipment and from this data we deduce the cost-effectiveness of the CRAY-1 in our field. (orig.)
Zhang, Han-Wei; Zheng, Yong; Du, Lan; Pan, Guan-Song
The tidal variation in Earth rotation rate is a periodical response to solar-lunar tide generating potential (TGP). Some theoretical formulae are given here based on Doodson development of TGP including the variations in Earth rotation rate, LOD and UT1. Finally the zonal tidal effect on the variation in the fluid core Earth rotation rate is calculated according to the formula deduced by Xi Qinwen (1995). The calculation shows that the results in this paper are well consistent with the ones in IERS (96), which indicates the correctness of the theoretical formula we deduced. It is also shown that the effects from the high frequency parts are relatively small, within the observing precision so far; relatively large effects due to the lower parts, which should be able to be seperated from the observed data, are actually difficult to make because of the influence from some non-tidal factors as well as short time span data.
International Nuclear Information System (INIS)
Yu Zhengqin; Li Keqin; Xiang Hengquan
2006-01-01
Objective: To investigate the changes of serum SOD contents and T-cell subsets distribution type after leukocyte-deduced red blood cell transfusion in patients with lung cancer. Methods: Serum SOD levels was measured with RIA and T-cell subsets distribution type was detected with monoclonal antibody technic both before and after leukocyte-deduced red blood cell transfusion in 32 patients with lung cancer and 35 normal controls. Results: Before treatment, the serum levels of SOD and T-cell CIM/ CD8 value were significantly lower in the patients than those in controls (P 0.05). Conclusion: Determination of serum SOD level and T-cell subsets distribution type is clinically useful in the management of patients with lung cancer. (authors)
Charon, E.; Aléon, J.; Rouzaud, J.-N.
2014-10-01
Lodran. Carbon phases in Lodran would have been formed by the secondary carbonization of hydrocarbon fluids released during the primary carbonization of IOM. In the framework of this model, the C isotopic compositions can be reproduced using Rayleigh distillation at each carbonization step and the N isotopic compositions can be understood as resulting from the variable loss and preservation of 15N-rich nitriles (δ15N ∼ +800‰) and 15N-poor pyrroles (δ15N = -140‰) during carbonization. The combined interpretation of the temperatures deduced from this model, petrographic cooling rates, and thermochronological indicators suggest that the CI-CM IOM could have been introduced in the parent-body by an impact, about 10 Myr after solar system formation.
Nabi, Jameel-Un; Böyükata, Mahmut
2016-03-01
We investigate even-even nuclei in the A ∼ 70 mass region within the framework of the proton-neutron quasi-particle random phase approximation (pn-QRPA) and the interacting boson model-1 (IBM-1). Our work includes calculation of the energy spectra and the potential energy surfaces V (β , γ) of Zn, Ge, Se, Kr and Sr nuclei with the same proton and neutron number, N = Z. The parametrization of the IBM-1 Hamiltonian was performed for the calculation of the energy levels in the ground state bands. Geometric shape of the nuclei was predicted by plotting the potential energy surfaces V (β , γ) obtained from the IBM-1 Hamiltonian in the classical limit. The pn-QRPA model was later used to compute half-lives of the neutron-deficient nuclei which were found to be in very good agreement with the measured ones. The pn-QRPA model was also used to calculate the Gamow-Teller strength distributions and was found to be in decent agreement with the measured data. We further calculate the electron capture and positron decay rates for these N = Z waiting point (WP) nuclei in the stellar environment employing the pn-QRPA model. For the rp-process conditions, our total weak rates are within a factor two compared with the Skyrme HF +BCS +QRPA calculation. All calculated electron capture rates are comparable to the competing positron decay rates under rp-process conditions. Our study confirms the finding that electron capture rates form an integral part of the weak rates under rp-process conditions and should not be neglected in the nuclear network calculations.
Invert Effective Thermal Conductivity Calculation
International Nuclear Information System (INIS)
M.J. Anderson; H.M. Wade; T.L. Mitchell
2000-01-01
The objective of this calculation is to evaluate the temperature-dependent effective thermal conductivities of a repository-emplaced invert steel set and surrounding ballast material. The scope of this calculation analyzes a ballast-material thermal conductivity range of 0.10 to 0.70 W/m · K, a transverse beam spacing range of 0.75 to 1.50 meters, and beam compositions of A 516 carbon steel and plain carbon steel. Results from this calculation are intended to support calculations that identify waste package and repository thermal characteristics for Site Recommendation (SR). This calculation was developed by Waste Package Department (WPD) under Office of Civilian Radioactive Waste Management (OCRWM) procedure AP-3.12Q, Revision 1, ICN 0, Calculations
Global nuclear-structure calculations
International Nuclear Information System (INIS)
Moeller, P.; Nix, J.R.
1990-01-01
The revival of interest in nuclear ground-state octupole deformations that occurred in the 1980's was stimulated by observations in 1980 of particularly large deviations between calculated and experimental masses in the Ra region, in a global calculation of nuclear ground-state masses. By minimizing the total potential energy with respect to octupole shape degrees of freedom in addition to ε 2 and ε 4 used originally, a vastly improved agreement between calculated and experimental masses was obtained. To study the global behavior and interrelationships between other nuclear properties, we calculate nuclear ground-state masses, spins, pairing gaps and Β-decay and half-lives and compare the results to experimental qualities. The calculations are based on the macroscopic-microscopic approach, with the microscopic contributions calculated in a folded-Yukawa single-particle potential
CALCULATION OF LASER CUTTING COSTS
Directory of Open Access Journals (Sweden)
Bogdan Nedic
2016-09-01
Full Text Available The paper presents description methods of metal cutting and calculation of treatment costs based on model that is developed on Faculty of mechanical engineering in Kragujevac. Based on systematization and analysis of large number of calculation models of cutting with unconventional methods, mathematical model is derived, which is used for creating a software for calculation costs of metal cutting. Software solution enables resolving the problem of calculating the cost of laser cutting, comparison' of costs made by other unconventional methods and provides documentation that consists of reports on estimated costs.
Calculation of Rydberg interaction potentials
DEFF Research Database (Denmark)
Weber, Sebastian; Tresp, Christoph; Menke, Henri
2017-01-01
for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up...... to higher multipole orders on a desktop computer. Finally, we present example calculations showing the relevance of the full interaction calculation to current experiments. Our software for calculating Rydberg potentials including all features discussed in this tutorial is available as open source....
... ounces of regular beer, 5 ounces of table wine, or 1.5 ounces of 80-proof distilled spirits. Distilled spirits include vodka, whiskey, gin, rum, and ... is 5% alcohol by volume (alc/vol), table wine is about 12% alc/vol, and straight 80-proof distilled spirits is 40% alc/vol. The percent alcohol by ...
International Nuclear Information System (INIS)
Obioha, F.I.; Gillies, N.E.; Cullen, B.M.; Walker, H.C.; Alper, T.
1984-01-01
E. coli were irradiated in the presence of 100% oxygen, oxygen-free nitrogen and mixtures of 1.01, 0.59, 0.3, 0.1 and 0.06% oxygen in nitrogen. Changes in sensitivity with pO 2 conformed with the Alper and Howard-Flanders equation for bacteria treated after irradiation by penicillin as well as for the untreated ones. Values of m were respectively 4.8 and 3.3; values of K were identical, within experimental error, (4.4 mmHg). Sensitivity to induction of the bacterial membrane penicillin-sensitive lesion was calculated from the difference in the reciprocals of D 0 values proper to untreated and treated bacteria, for every gas used. The value of m could not be directly calculated because the effect of penicillin on anoxically irradiated bacteria was not detectable. For that reason, a transformation of the oxygen equation was used, allowing estimates to be made of both m and K, provided the results conformed with the equation. Within experimental error they did. Calculated values of m and K for induction of the penicillin-sensitive lesion were respectively 8 and 5.9 mmHg, but it is shown that the oxygen enhancement ratio was probably underestimated and the value overestimated. (author)
The two-wave X-ray field calculated by means of integral-equation methods
International Nuclear Information System (INIS)
Bremer, J.
1984-01-01
The problem of calculating the two-wave X-ray field on the basis of the Takagi-Taupin equations is discussed for the general case of curved lattice planes. A two-dimensional integral equation which incorporates the nature of the incoming radiation, the form of the crystal/vacuum boundary, and the curvature of the structure, is deduced. Analytical solutions for the symmetrical Laue case with incoming plane waves are obtained directly for perfect crystals by means of iteration. The same method permits a simple derivation of the narrow-wave Laue and Bragg cases. Modulated wave fronts are discussed, and it is shown that a cut-off in the width of an incoming plane wave leads to lateral oscillations which are superimposed on the Pendelloesung fringes. Bragg and Laue shadow fields are obtained. The influence of a non-zero kernel is discussed and a numerical procedure for calculating wave amplitudes in curved crystals is presented. (Auth.)
Application of the particle-in-cell method in propagation calculations
International Nuclear Information System (INIS)
Voelz, E.
1979-01-01
The Particle-in-Cell-Method that is capable of calculating the spreading of a plume in the atmosphere under instationary and inhomogeneous conditions, has a systematical advantage over the steady state Gaussian plume model usually used. Especially the fixed-point concentration time integral is calculated realistically instead of the locally integrated concentration at a constant time as is done in the plume model. Inaccuracies due to the computational techniques may be avoided in this way. On the other hand, at first the turbulent diffusion coefficients that describe the diffusion in the particle-in-cell method, must be prepared for all diffusion types. Thereby the diffusion coefficients can be seen to be mainly deduced in the steady state. This is one reason why they cannot be used in an optimal sense in a model that actually works instationary. (orig.) [de
Fatigue analysis - computation of the actual strain range using elastic calculation
International Nuclear Information System (INIS)
Roche, R.L.
1987-04-01
The design codes used in nuclear industry do not contain all the same rules allowing to deduce from an elastic calculation the actual deformation variation. Knowledge of strain range is needed for fatigue analysis. Elastic calculation does not give the actual range. The aim of this paper is discussing ways to correct elastic results and proposing a practical method to do it. Two corrections are required. The first one is related to elastic follow up effect when shakedown is not obtained (correction on secondary stress). The second one is related to stress raisers effect (correction on peak stress). It is shown that NEUBER's rule is not convenient for the second correction when shakedown is not fulfilled [fr
Core calculational techniques and procedures
International Nuclear Information System (INIS)
Romano, J.J.
1977-10-01
Described are the procedures and techniques employed by B and W in core design analyses of power peaking, control rod worths, and reactivity coefficients. Major emphasis has been placed on current calculational tools and the most frequently performed calculations over the operating power range
Economic calculation in socialist countries
Ellman, M.; Durlauf, S.N.; Blume, L.E.
2008-01-01
In the 1930s, when the classical socialist system emerged, economic decisions were based not on detailed and precise economic methods of calculation but on rough and ready political methods. An important method of economic calculation - particularly in the post-Stalin period - was that of
Calculation of Spectra of Solids:
DEFF Research Database (Denmark)
Lindgård, Per-Anker
1975-01-01
The Gilat-Raubenheimer method simplified to tetrahedron division is used to calculate the real and imaginary part of the dynamical response function for electrons. A frequency expansion for the real part is discussed. The Lindhard function is calculated as a test for numerical accuracy...
Calculator. Owning a Small Business.
Parma City School District, OH.
Seven activities are presented in this student workbook designed for an exploration of small business ownership and the use of the calculator in this career. Included are simulated situations in which students must use a calculator to compute property taxes; estimate payroll taxes and franchise taxes; compute pricing, approximate salaries,…
Shielding calculational system for plutonium
International Nuclear Information System (INIS)
Zimmerman, M.G.; Thomsen, D.H.
1975-08-01
A computer calculational system has been developed and assembled specifically for calculating dose rates in AEC plutonium fabrication facilities. The system consists of two computer codes and all nuclear data necessary for calculation of neutron and gamma dose rates from plutonium. The codes include the multigroup version of the Battelle Monte Carlo code for solution of general neutron and gamma shielding problems and the PUSHLD code for solution of shielding problems where low energy gamma and x-rays are important. The nuclear data consists of built in neutron and gamma yields and spectra for various plutonium compounds, an automatic calculation of age effects and all cross-sections commonly used. Experimental correlations have been performed to verify portions of the calculational system. (23 tables, 7 figs, 16 refs) (U.S.)
Closure and Sealing Design Calculation
International Nuclear Information System (INIS)
T. Lahnalampi; J. Case
2005-01-01
The purpose of the ''Closure and Sealing Design Calculation'' is to illustrate closure and sealing methods for sealing shafts, ramps, and identify boreholes that require sealing in order to limit the potential of water infiltration. In addition, this calculation will provide a description of the magma that can reduce the consequences of an igneous event intersecting the repository. This calculation will also include a listing of the project requirements related to closure and sealing. The scope of this calculation is to: summarize applicable project requirements and codes relating to backfilling nonemplacement openings, removal of uncommitted materials from the subsurface, installation of drip shields, and erecting monuments; compile an inventory of boreholes that are found in the area of the subsurface repository; describe the magma bulkhead feature and location; and include figures for the proposed shaft and ramp seals. The objective of this calculation is to: categorize the boreholes for sealing by depth and proximity to the subsurface repository; develop drawing figures which show the location and geometry for the magma bulkhead; include the shaft seal figures and a proposed construction sequence; and include the ramp seal figure and a proposed construction sequence. The intent of this closure and sealing calculation is to support the License Application by providing a description of the closure and sealing methods for the Safety Analysis Report. The closure and sealing calculation will also provide input for Post Closure Activities by describing the location of the magma bulkhead. This calculation is limited to describing the final configuration of the sealing and backfill systems for the underground area. The methods and procedures used to place the backfill and remove uncommitted materials (such as concrete) from the repository and detailed design of the magma bulkhead will be the subject of separate analyses or calculations. Post-closure monitoring will not
Reactor core performance calculating device
International Nuclear Information System (INIS)
Tominaga, Kenji; Bando, Masaru; Sano, Hiroki; Maruyama, Hiromi.
1995-01-01
The device of the present invention can calculate a power distribution efficiently at high speed by a plurality of calculation means while taking an amount of the reactor state into consideration. Namely, an input device takes data from a measuring device for the amount of the reactor core state such as a large number of neutron detectors disposed in the reactor core for monitoring the reactor state during operation. An input data distribution device comprises a state recognition section and a data distribution section. The state recognition section recognizes the kind and amount of the inputted data and information of the calculation means. The data distribution section analyzes the characteristic of the inputted data, divides them into a several groups, allocates them to each of the calculation means for the purpose of calculating the reactor core performance efficiently at high speed based on the information from the state recognition section. A plurality of the calculation means calculate power distribution of each of regions based on the allocated inputted data, to determine the power distribution of the entire reactor core. As a result, the reactor core can be evaluated at high accuracy and at high speed irrespective of the whole reactor core or partial region. (I.S.)
Directory of Open Access Journals (Sweden)
A. V. Mikhailov
1997-11-01
Full Text Available A self-consistent method for day-time F2-region modelling was applied to the analysis of Millstone Hill incoherent scatter observations during the storm period of March 16-22, 1990. The method allows us to calculate in a self-consistent way neutral composition, temperature and meridional wind as well as the ionized species height distribution. Theoretically calculated Ne(h profiles fit the observed daytime ones with great accuracy in the whole range of heights above 150 km for both quiet and disturbed days. The overall increase in Tex by 270 K from March 16 to March 22 reflects the increase of solar activity level during the period in question. A 30% decrease in [O] and a two-fold increase in [N2] are calculated for the disturbed day of March 22 relative to quiet time prestorm conditions. Only a small reaction to the first geomagnetic disturbance on March 18 and the initial phase of the second storm on March 20 was found in [O] and [N2] variations. The meridional neutral wind inferred from plasma vertical drift clearly demonstrates the dependence on the geomagnetic activity level being more equatorward on disturbed days. Small positive F2-layer storm effects on March 18 and 20 are totally attributed to the decrease in the northward neutral wind but not to changes in neutral composition. A moderate (by a factor of 1.5 O/N2 ratio decrease relative to the MSIS-83 model prediction is required to describe the observed NmF2 decrease on the most disturbed day of March 22, but virtually no change of this ratio is needed for March 21.
Zhang, Zhen; Xia, Changliang; Yan, Yan; Geng, Qiang; Shi, Tingna
2017-08-01
Due to the complicated rotor structure and nonlinear saturation of rotor bridges, it is difficult to build a fast and accurate analytical field calculation model for multilayer interior permanent magnet (IPM) machines. In this paper, a hybrid analytical model suitable for the open-circuit field calculation of multilayer IPM machines is proposed by coupling the magnetic equivalent circuit (MEC) method and the subdomain technique. In the proposed analytical model, the rotor magnetic field is calculated by the MEC method based on the Kirchhoff's law, while the field in the stator slot, slot opening and air-gap is calculated by subdomain technique based on the Maxwell's equation. To solve the whole field distribution of the multilayer IPM machines, the coupled boundary conditions on the rotor surface are deduced for the coupling of the rotor MEC and the analytical field distribution of the stator slot, slot opening and air-gap. The hybrid analytical model can be used to calculate the open-circuit air-gap field distribution, back electromotive force (EMF) and cogging torque of multilayer IPM machines. Compared with finite element analysis (FEA), it has the advantages of faster modeling, less computation source occupying and shorter time consuming, and meanwhile achieves the approximate accuracy. The analytical model is helpful and applicable for the open-circuit field calculation of multilayer IPM machines with any size and pole/slot number combination.
Radial electromagnetic force calculation of induction motor based on multi-loop theory
Directory of Open Access Journals (Sweden)
HE Haibo
2017-12-01
Full Text Available [Objectives] In order to study the vibration and noise of induction motors, a method of radial electromagnetic force calculation is established on the basis of the multi-loop model.[Methods] Based on the method of calculating air-gap magneto motive force according to stator and rotor fundamental wave current, the analytic formulas are deduced for calculating the air-gap magneto motive force and radial electromagnetic force generated in accordance with any stator winding and rotor conducting bar current. The multi-loop theory and calculation method for the electromagnetic parameters of a motor are introduced, and a dynamic simulation model of an induction motor built to achieve the current of the stator winding and rotor conducting bars, and obtain the calculation formula of radial electromagnetic force. The radial electromagnetic force and vibration are then estimated.[Results] The experimental results indicate that the vibration acceleration frequency and amplitude of the motor are consistent with the experimental results.[Conclusions] The results and calculation method can support the low noise design of converters.
Alaska Village Electric Load Calculator
Energy Technology Data Exchange (ETDEWEB)
Devine, M.; Baring-Gould, E. I.
2004-10-01
As part of designing a village electric power system, the present and future electric loads must be defined, including both seasonal and daily usage patterns. However, in many cases, detailed electric load information is not readily available. NREL developed the Alaska Village Electric Load Calculator to help estimate the electricity requirements in a village given basic information about the types of facilities located within the community. The purpose of this report is to explain how the load calculator was developed and to provide instructions on its use so that organizations can then use this model to calculate expected electrical energy usage.
Reactor calculations and nuclear information
International Nuclear Information System (INIS)
Lang, D.W.
1977-12-01
The relationship of sets of nuclear parameters and the macroscopic reactor quantities that can be calculated from them is examined. The framework of the study is similar to that of Usachev and Bobkov. The analysis is generalised and some properties required by common sense are demonstrated. The form of calculation permits revision of the parameter set. It is argued that any discrepancy between a calculation and measurement of a macroscopic quantity is more useful when applied directly to prediction of other macroscopic quantities than to revision of the parameter set. The mathematical technique outlined is seen to describe common engineering practice. (Author)
Practical astronomy with your calculator
Duffett-Smith, Peter
1989-01-01
Practical Astronomy with your Calculator, first published in 1979, has enjoyed immense success. The author's clear and easy to follow routines enable you to solve a variety of practical and recreational problems in astronomy using a scientific calculator. Mathematical complexity is kept firmly in the background, leaving just the elements necessary for swiftly making calculations. The major topics are: time, coordinate systems, the Sun, the planetary system, binary stars, the Moon, and eclipses. In the third edition there are entirely new sections on generalised coordinate transformations, nutr
Calculation of pion form factor
International Nuclear Information System (INIS)
Vahedi, N.; Amirarjomand, S.
1975-09-01
The pion form factor is calculated using the structure function Wsub(2), which incorporates kinematical constraints, threshold behaviour and scaling. The Bloom-Gilman sum rule is used and only the two leading Regge trajectories are taken into account
Landfill Gas Energy Benefits Calculator
This page contains the LFG Energy Benefits Calculator to estimate direct, avoided, and total greenhouse gas reductions, as well as environmental and energy benefits, for a landfill gas energy project.
Calculate Your Body Mass Index
... Can! ) Health Professional Resources Calculate Your Body Mass Index Body mass index (BMI) is a measure of body fat based ... Health Information Email Alerts Jobs and Careers Site Index About NHLBI National Institute of Health Department of ...
Transfer Area Mechanical Handling Calculation
International Nuclear Information System (INIS)
Dianda, B.
2004-01-01
This calculation is intended to support the License Application (LA) submittal of December 2004, in accordance with the directive given by DOE correspondence received on the 27th of January 2004 entitled: ''Authorization for Bechtel SAX Company L.L. C. to Include a Bare Fuel Handling Facility and Increased Aging Capacity in the License Application, Contract Number DE-AC--28-01R W12101'' (Arthur, W.J., I11 2004). This correspondence was appended by further Correspondence received on the 19th of February 2004 entitled: ''Technical Direction to Bechtel SAIC Company L.L. C. for Surface Facility Improvements, Contract Number DE-AC--28-OIRW12101; TDL No. 04-024'' (BSC 2004a). These documents give the authorization for a Fuel Handling Facility to be included in the baseline. The purpose of this calculation is to establish preliminary bounding equipment envelopes and weights for the Fuel Handling Facility (FHF) transfer areas equipment. This calculation provides preliminary information only to support development of facility layouts and preliminary load calculations. The limitations of this preliminary calculation lie within the assumptions of section 5 , as this calculation is part of an evolutionary design process. It is intended that this calculation is superseded as the design advances to reflect information necessary to support License Application. The design choices outlined within this calculation represent a demonstration of feasibility and may or may not be included in the completed design. This calculation provides preliminary weight, dimensional envelope, and equipment position in building for the purposes of defining interface variables. This calculation identifies and sizes major equipment and assemblies that dictate overall equipment dimensions and facility interfaces. Sizing of components is based on the selection of commercially available products, where applicable. This is not a specific recommendation for the future use of these components or their
CONTAIN calculations; CONTAIN-Rechnungen
Energy Technology Data Exchange (ETDEWEB)
Scholtyssek, W.
1995-08-01
In the first phase of a benchmark comparison, the CONTAIN code was used to calculate an assumed EPR accident `medium-sized leak in the cold leg`, especially for the first two days after initiation of the accident. The results for global characteristics compare well with those of FIPLOC, MELCOR and WAVCO calculations, if the same materials data are used as input. However, significant differences show up for local quantities such as flows through leakages. (orig.)
Numerical calculations near spatial infinity
International Nuclear Information System (INIS)
Zenginoglu, Anil
2007-01-01
After describing in short some problems and methods regarding the smoothness of null infinity for isolated systems, I present numerical calculations in which both spatial and null infinity can be studied. The reduced conformal field equations based on the conformal Gauss gauge allow us in spherical symmetry to calculate numerically the entire Schwarzschild-Kruskal spacetime in a smooth way including spacelike, null and timelike infinity and the domain close to the singularity
Calculating radiation exposure and dose
International Nuclear Information System (INIS)
Hondros, J.
1987-01-01
This paper discusses the methods and procedures used to calculate the radiation exposures and radiation doses to designated employees of the Olympic Dam Project. Each of the three major exposure pathways are examined. These are: gamma irradiation, radon daughter inhalation and radioactive dust inhalation. A further section presents ICRP methodology for combining individual pathway exposures to give a total dose figure. Computer programs used for calculations and data storage are also presented briefly
Lorenz-Meyer, W.
1977-01-01
In connection with the question on the applicability of test results obtained from cryogenic wind tunnels to the large-scale model the similarity parameter is referred to. A simple method is given for calculating the similarity parameter. From the numerical values obtained it can be deduced that nitrogen behaves practically like an ideal gas when it is close to the saturation point and in a pressure range up to 4 bar. The influence of this parameter on the pressure distribution of a supercritical profile confirms this finding.
Calculation of Rydberg interaction potentials
International Nuclear Information System (INIS)
Weber, Sebastian; Büchler, Hans Peter; Tresp, Christoph; Urvoy, Alban; Hofferberth, Sebastian; Menke, Henri; Firstenberg, Ofer
2017-01-01
The strong interaction between individual Rydberg atoms provides a powerful tool exploited in an ever-growing range of applications in quantum information science, quantum simulation and ultracold chemistry. One hallmark of the Rydberg interaction is that both its strength and angular dependence can be fine-tuned with great flexibility by choosing appropriate Rydberg states and applying external electric and magnetic fields. More and more experiments are probing this interaction at short atomic distances or with such high precision that perturbative calculations as well as restrictions to the leading dipole–dipole interaction term are no longer sufficient. In this tutorial, we review all relevant aspects of the full calculation of Rydberg interaction potentials. We discuss the derivation of the interaction Hamiltonian from the electrostatic multipole expansion, numerical and analytical methods for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up to higher multipole orders on a desktop computer. Finally, we present example calculations showing the relevance of the full interaction calculation to current experiments. Our software for calculating Rydberg potentials including all features discussed in this tutorial is available as open source. (tutorial)
International Nuclear Information System (INIS)
Masrour, R.; Jabar, A.; Hlil, E.K.; Hamedoun, M.; Benyoussef, A.; Hourmatallah, A.; Rezzouk, A.; Bouslykhane, K.; Benzakour, N.
2017-01-01
Self-consistent ab initio calculations, based on Density Functional Theory (DFT) approach and using Full potential Linear Augmented Plane Wave (FLAPW) method, are performed to investigate both electronic and magnetic properties of the Mn 2 NiAl. Magnetic moment considered to lie along (001) axes are computed. Obtained data from ab initio calculations are used as input for Monte Carlo simulations to compute other magnetic parameters. Also, the magnetic properties of Mn 2 NiAl are studied using the Monte Carlo simulations. The variation of magnetization and magnetic susceptibility with the reduced temperature of Mn 2 NiAl are investigated. The transition temperature of this system is deduced for different values exchange interaction and crystal field. The thermal total magnetization has been obtained, and the magnetic hysteresis cycle is established. The total magnetic moment is superior to those obtained by the other method and is mainly determined by the antiparallel aligned Mn I , Mn II and Ni spin moments. The superparamagnetic phase is found at the neighborhood of transition temperature. - Highlights: • Ab initio calculations are used to study magnetic and electronic properties of Mn 2 NiX. • The transition temperature of Mn 2 NiX is established. • The magnetic hysteresis cycle of M n2 NiX (X = Al, Ga, In, Sn) is deduced. • The magnetic coercive field of Mn 2 NiX (X = Al, Ga, In, Sn) is given.
Precision half-life measurement of 11C: The most precise mirror transition F t value
Valverde, A. A.; Brodeur, M.; Ahn, T.; Allen, J.; Bardayan, D. W.; Becchetti, F. D.; Blankstein, D.; Brown, G.; Burdette, D. P.; Frentz, B.; Gilardy, G.; Hall, M. R.; King, S.; Kolata, J. J.; Long, J.; Macon, K. T.; Nelson, A.; O'Malley, P. D.; Skulski, M.; Strauss, S. Y.; Vande Kolk, B.
2018-03-01
Background: The precise determination of the F t value in T =1 /2 mixed mirror decays is an important avenue for testing the standard model of the electroweak interaction through the determination of Vu d in nuclear β decays. 11C is an interesting case, as its low mass and small QE C value make it particularly sensitive to violations of the conserved vector current hypothesis. The present dominant source of uncertainty in the 11CF t value is the half-life. Purpose: A high-precision measurement of the 11C half-life was performed, and a new world average half-life was calculated. Method: 11C was created by transfer reactions and separated using the TwinSol facility at the Nuclear Science Laboratory at the University of Notre Dame. It was then implanted into a tantalum foil, and β counting was used to determine the half-life. Results: The new half-life, t1 /2=1220.27 (26 ) s, is consistent with the previous values but significantly more precise. A new world average was calculated, t1/2 world=1220.41 (32 ) s, and a new estimate for the Gamow-Teller to Fermi mixing ratio ρ is presented along with standard model correlation parameters. Conclusions: The new 11C world average half-life allows the calculation of a F tmirror value that is now the most precise value for all superallowed mixed mirror transitions. This gives a strong impetus for an experimental determination of ρ , to allow for the determination of Vu d from this decay.
Mordred: a molecular descriptor calculator.
Moriwaki, Hirotomo; Tian, Yu-Shi; Kawashita, Norihito; Takagi, Tatsuya
2018-02-06
Molecular descriptors are widely employed to present molecular characteristics in cheminformatics. Various molecular-descriptor-calculation software programs have been developed. However, users of those programs must contend with several issues, including software bugs, insufficient update frequencies, and software licensing constraints. To address these issues, we propose Mordred, a developed descriptor-calculation software application that can calculate more than 1800 two- and three-dimensional descriptors. It is freely available via GitHub. Mordred can be easily installed and used in the command line interface, as a web application, or as a high-flexibility Python package on all major platforms (Windows, Linux, and macOS). Performance benchmark results show that Mordred is at least twice as fast as the well-known PaDEL-Descriptor and it can calculate descriptors for large molecules, which cannot be accomplished by other software. Owing to its good performance, convenience, number of descriptors, and a lax licensing constraint, Mordred is a promising choice of molecular descriptor calculation software that can be utilized for cheminformatics studies, such as those on quantitative structure-property relationships.
Propagation calculation for reactor cases
Energy Technology Data Exchange (ETDEWEB)
Yang Yanhua [School of Power and Energy Engineering, Shanghai Jiao Tong Univ., Shanghai (China); Moriyama, K.; Maruyama, Y.; Nakamura, H.; Hashimoto, K. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
2000-11-01
The propagation of steam explosion for real reactor geometry and conditions are investigated by using the computer code JASMINE-pro. The ex-vessel steam explosion is considered, which is described as follow: during the accident of reactor core meltdown, the molten core melts a hole at the bottom of reactor vessel and causes the higher temperature core fuel being leaked into the water pool below reactor vessel. During the melt-water mixing interaction process, the high temperature melt evaporates the cool water at an extreme high rate and might induce a steam explosion. A steam explosion could experience first the premixing phase and then the propagation explosion phase. For a propagation calculation, we should know the information about the initial fragmentation time, the total melt mass, premixing region size, initial void fraction and distribution of the melt volume fraction, and so on. All the initial conditions used in this calculation are based on analyses from some simple assumptions and the observation from the experiments. The results show that the most important parameter for the initial condition of this phase is the total mass and its initial distribution. This gives the requirement for a premixing calculation. On the other hand, for higher melt volume fraction case, the fragmentation is strong so that the local pressure can exceed over the EOS maximum pressure of the code, which lead to the incorrect calculation or divergence of the calculation. (Suetake, M.)
International Nuclear Information System (INIS)
Ivascu, M.
1983-10-01
Computer codes incorporating advanced nuclear models (optical, statistical and pre-equilibrium decay nuclear reaction models) were used to calculate neutron cross sections needed for fusion reactor technology. The elastic and inelastic scattering (n,2n), (n,p), (n,n'p), (n,d) and (n,γ) cross sections for stable molybdenum isotopes Mosup(92,94,95,96,97,98,100) and incident neutron energy from about 100 keV or a threshold to 20 MeV were calculated using the consistent set of input parameters. The hydrogen production cross section which determined the radiation damage in structural materials of fusion reactors can be simply deduced from the presented results. The more elaborated microscopic models of nuclear level density are required for high accuracy calculations
The calculation of proton and secondary electron stopping powers in liquid water
International Nuclear Information System (INIS)
Marouane, Abdelhak; Inchaouh, Jamal; Ouaskit, Said; Fathi, Ahmed
2012-01-01
The stopping power of energetic protons in liquid water has been calculated using a new model based on different theoretical and semi-empirical approaches. In this model, we consider the relativistic corrections along with the electronic and nuclear stopping power. The present work accounts for the different interactions made with electrons and nuclei inside the target. Interactions of the incident particle with the target's electrons dominate in the high energy regime; in the low energy regime, the interactions of the projectile with the target nuclei contribute importantly and are included in the calculation. We also compute the stopping cross sections and the stopping power of secondary electrons ejected from proton and hydrogen ionization impact, and generated by hydrogen electron loss processes. The consideration of secondary electrons' stopping power can contribute to the study of nano-dosimetry. Our results are in good agreement with existing experimental data. This calculation model can be useful for different applications in medical physics and space radiation health, such as hadron therapy for cancer treatment or radiation protection for astronauts. - Highlights: ► We discussed the stopping cross sections at the Bragg peak region of primary and secondary processes. ► We considered the corrections of incident particle energy focusing on the Rudds semi-empirical model. ► We calculated the electronic and nuclear stopping power, and we deduced the total stopping power. ► We calculated the stopping power of the secondary electrons.
Ohta, Y.; Ohzono, M.; Takahashi, H.; Kawamoto, S.; Hino, R.
2017-12-01
A large and destructive earthquake (Mjma 7.3) occurred on April 15, 2016 in Kumamoto region, southwestern Japan. This earthquake was accompanied approximately 32 s later by an M 6 earthquake in central Oita region, which hypocenter located 80 km northeast from the hypocenter of the mainshock of the Kumamoto earthquake. This triggered earthquake also had the many aftershocks in and around the Oita region. It is important to understand how to occur such chain-reacted earthquake sequences. We used the 1Hz dual-frequency phase and range data from GEONET in Kyushu island. The data were processed using GIPSY-OASIS (version 6.4). We adopoted kinematic PPP strategy for the coordinate estimation. The reference GPS satellite orbit and 5 s clock information were obtained using the CODE product. We also applied simple sidereal filter technique for the estimated time series. Based on the obtained 1Hz GNSS time series, we estimated the areal strain and principle strain field using the method of the Shen et al. (1996). For the assessment of the dynamic strain, firstly we calculated the averaged absolute value of areal strain field between 60-85s after the origin time of the mainshock of the Kumamoto earthquake which was used as the "reference" static strain field. Secondly, we estimated the absolute value of areal strain in each time step. Finally, we calculated the strain ratio in each time step relative to the "reference". Based on this procedure, we can extract the spatial and temporal characteristic of the dynamic strain in each time step. Extracted strain ratio clearly shows the spatial and temporal dynamic strain characteristic. When an attention is paid to a region of triggered Oita earthquake, the timing of maximum dynamic strain ratio in the epicenter just corresponds to the origin time of the triggered event. It strongly suggested that the large dynamic strain may trigger the Oita event. The epicenter of the triggered earthquake located within the geothermal region. In
Energy Technology Data Exchange (ETDEWEB)
Zhang, Zhen [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China); Xia, Changliang [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China); Tianjin Engineering Center of Electric Machine System Design and Control, Tianjin 300387 (China); Yan, Yan, E-mail: yanyan@tju.edu.cn [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China); Geng, Qiang [Tianjin Engineering Center of Electric Machine System Design and Control, Tianjin 300387 (China); Shi, Tingna [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China)
2017-08-01
Highlights: • A hybrid analytical model is developed for field calculation of multilayer IPM machines. • The rotor magnetic field is calculated by the magnetic equivalent circuit method. • The field in the stator and air-gap is calculated by subdomain technique. • The magnetic scalar potential on rotor surface is modeled as trapezoidal distribution. - Abstract: Due to the complicated rotor structure and nonlinear saturation of rotor bridges, it is difficult to build a fast and accurate analytical field calculation model for multilayer interior permanent magnet (IPM) machines. In this paper, a hybrid analytical model suitable for the open-circuit field calculation of multilayer IPM machines is proposed by coupling the magnetic equivalent circuit (MEC) method and the subdomain technique. In the proposed analytical model, the rotor magnetic field is calculated by the MEC method based on the Kirchhoff’s law, while the field in the stator slot, slot opening and air-gap is calculated by subdomain technique based on the Maxwell’s equation. To solve the whole field distribution of the multilayer IPM machines, the coupled boundary conditions on the rotor surface are deduced for the coupling of the rotor MEC and the analytical field distribution of the stator slot, slot opening and air-gap. The hybrid analytical model can be used to calculate the open-circuit air-gap field distribution, back electromotive force (EMF) and cogging torque of multilayer IPM machines. Compared with finite element analysis (FEA), it has the advantages of faster modeling, less computation source occupying and shorter time consuming, and meanwhile achieves the approximate accuracy. The analytical model is helpful and applicable for the open-circuit field calculation of multilayer IPM machines with any size and pole/slot number combination.
Calculation of magnetic hyperfine constants
International Nuclear Information System (INIS)
Bufaical, R.F.; Maffeo, B.; Brandi, H.S.
1975-01-01
The magnetic hyperfine constants of the V sub(K) center in CaF 2 , SrF 2 and BaF 2 have been calculated assuming a phenomenological model, based on the F 2 - 'central molucule', to describe the wavefunction of the defect. Calculations have shown that introduction of a small degree of covalence, between this central molecule and neighboring ions, is necessary to improve the electronic structure description of the defect. It was also shown that the results for the hyperfine constants are strongly dependent on the relaxations of the ions neighboring the central molecule; these relaxations have been determined by fitting the experimental data. The present results are compared with other previous calculations where similar and different theoretical methods have been used
Parameters calculation of shielding experiment
International Nuclear Information System (INIS)
Gavazza, S.
1986-02-01
The radiation transport methodology comparing the calculated reactions and dose rates for neutrons and gama-rays, with experimental measurements obtained on iron shield, irradiated in the YAYOI reactor is evaluated. The ENDF/B-IV and VITAMIN-C libraries and the AMPX-II modular system, for cross sections generation collapsed by the ANISN code were used. The transport calculations were made using the DOT 3.5 code, adjusting the boundary iron shield source spectrum to the reactions and dose rates, measured at the beginning of shield. The neutron and gamma ray distributions calculated on the iron shield presented reasonable agreement with experimental measurements. An experimental arrangement using the IEA-R1 reactor to determine a shielding benchmark is proposed. (Author) [pt
Insertion device calculations with mathematica
Energy Technology Data Exchange (ETDEWEB)
Carr, R. [Stanford Synchrotron Radiation Lab., CA (United States); Lidia, S. [Univ. of California, Davis, CA (United States)
1995-02-01
The design of accelerator insertion devices such as wigglers and undulators has usually been aided by numerical modeling on digital computers, using code in high level languages like Fortran. In the present era, there are higher level programming environments like IDL{reg_sign}, MatLab{reg_sign}, and Mathematica{reg_sign} in which these calculations may be performed by writing much less code, and in which standard mathematical techniques are very easily used. The authors present a suite of standard insertion device modeling routines in Mathematica to illustrate the new techniques. These routines include a simple way to generate magnetic fields using blocks of CSEM materials, trajectory solutions from the Lorentz force equations for given magnetic fields, Bessel function calculations of radiation for wigglers and undulators and general radiation calculations for undulators.
PHEBUS-FPTO Benchmark calculations
International Nuclear Information System (INIS)
Shepherd, I.; Ball, A.; Trambauer, K.; Barbero, F.; Olivar Dominguez, F.; Herranz, L.; Biasi, L.; Fermandjian, J.; Hocke, K.
1991-01-01
This report summarizes a set of pre-test predictions made for the first Phebus-FP test, FPT-O. There were many different calculations, performed by various organizations and they represent the first attempt to calculate the whole experimental sequence, from bundle to containment. Quantitative agreement between the various calculations was not good but the particular models in the code responsible for disagreements were mostly identified. A consensus view was formed as to how the test would proceed. It was found that a successful execution of the test will require a different operating procedure than had been assumed here. Critical areas which require close attention are the need to devize a strategy for the power and flow in the bundle that takes account of uncertainties in the modelling and the shroud conductivity and the necessity to develop a reliable method to achieve the desired thermalhydraulic conditions in the containment
Sakkas, Vassilis; Lagios, Evangelos
2017-03-01
The implications of the earthquakes that took place in the central Ionian Islands in 2014 (Cephalonia, M w6.1, M w5.9) and 2015 (Lefkas, M w6.4) are described based on repeat measurements of the local GPS networks in Cephalonia and Ithaca, and the available continuous GPS stations in the broader area. The Lefkas earthquake occurred on a branch of the Cephalonia Transform Fault, affecting Cephalonia with SE displacements gradually decreasing from north ( 100 mm) to south ( 10 mm). This earthquake revealed a near N-S dislocation boundary separating Paliki Peninsula in western Cephalonia from the rest of the island, as well as another NW-SE trending fault that separates kinematically the northern and southern parts of Paliki. Strain field calculations during the interseismic period (2014-2015) indicate compression between Ithaca and Cephalonia, while extension appears during the following co-seismic period (2015-2016) including the 2015 Lefkas earthquake. Additional tectonically active zones with differential kinematic characteristics were also identified locally.
Automatic calculations of electroweak processes
International Nuclear Information System (INIS)
Ishikawa, T.; Kawabata, S.; Kurihara, Y.; Shimizu, Y.; Kaneko, T.; Kato, K.; Tanaka, H.
1996-01-01
GRACE system is an excellent tool for calculating the cross section and for generating event of the elementary process automatically. However it is not always easy for beginners to use. An interactive version of GRACE is being developed so as to be a user friendly system. Since it works exactly in the same environment as PAW, all functions of PAW are available for handling any histogram information produced by GRACE. As its application the cross sections of all elementary processes with up to 5-body final states induced by e + e - interaction are going to be calculated and to be summarized as a catalogue. (author)
Calculation methods in program CCRMN
Energy Technology Data Exchange (ETDEWEB)
Chonghai, Cai [Nankai Univ., Tianjin (China). Dept. of Physics; Qingbiao, Shen [Chinese Nuclear Data Center, Beijing, BJ (China)
1996-06-01
CCRMN is a program for calculating complex reactions of a medium-heavy nucleus with six light particles. In CCRMN, the incoming particles can be neutrons, protons, {sup 4}He, deuterons, tritons and {sup 3}He. the CCRMN code is constructed within the framework of the optical model, pre-equilibrium statistical theory based on the exciton model and the evaporation model. CCRMN is valid in 1{approx} MeV energy region, it can give correct results for optical model quantities and all kinds of reaction cross sections. This program has been applied in practical calculations and got reasonable results.
Friction and wear calculation methods
Kragelsky, I V; Kombalov, V S
1981-01-01
Friction and Wear: Calculation Methods provides an introduction to the main theories of a new branch of mechanics known as """"contact interaction of solids in relative motion."""" This branch is closely bound up with other sciences, especially physics and chemistry. The book analyzes the nature of friction and wear, and some theoretical relationships that link the characteristics of the processes and the properties of the contacting bodies essential for practical application of the theories in calculating friction forces and wear values. The effect of the environment on friction and wear is a
Selfconsistent calculations at finite temperatures
International Nuclear Information System (INIS)
Brack, M.; Quentin, P.
1975-01-01
Calculations have been done for the spherical nuclei 40 Ca, 208 Pb and the hypothetical superheavy nucleus with Z=114, A=298, as well as for the deformed nucleus 168 Yb. The temperature T was varied from zero up to 5 MeV. For T>3 MeV, some numerical problems arise in connection with the optimization of the basis when calculating deformed nuclei. However, at these high temperatures the occupation numbers in the continuum are sufficiently large so that the nucleus starts evaporating particles and no equilibrium state can be described. Results are obtained for excitation energies and entropies. (Auth.)
Benchmark neutron porosity log calculations
International Nuclear Information System (INIS)
Little, R.C.; Michael, M.; Verghese, K.; Gardner, R.P.
1989-01-01
Calculations have been made for a benchmark neutron porosity log problem with the general purpose Monte Carlo code MCNP and the specific purpose Monte Carlo code McDNL. For accuracy and timing comparison purposes the CRAY XMP and MicroVax II computers have been used with these codes. The CRAY has been used for an analog version of the MCNP code while the MicroVax II has been used for the optimized variance reduction versions of both codes. Results indicate that the two codes give the same results within calculated standard deviations. Comparisons are given and discussed for accuracy (precision) and computation times for the two codes
Molecular calculations with B functions
International Nuclear Information System (INIS)
Steinborn, E.O.; Homeier, H.H.H.; Ema, I.; Lopez, R.; Ramirez, G.
2000-01-01
A program for molecular calculations with B functions is reported and its performance is analyzed. All the one- and two-center integrals and the three-center nuclear attraction integrals are computed by direct procedures, using previously developed algorithms. The three- and four-center electron repulsion integrals are computed by means of Gaussian expansions of the B functions. A new procedure for obtaining these expansions is also reported. Some results on full molecular calculations are included to show the capabilities of the program and the quality of the B functions to represent the electronic functions in molecules
Lattice calculations in gauge theory
International Nuclear Information System (INIS)
Rebbi, C.
1985-01-01
The lattice formulation of quantum gauge theories is discussed as a viable technique for quantitative studies of nonperturbative effects in QCD. Evidence is presented to ascertain that whole classes of lattice actions produce a universal continuum limit. Discrepancies between numerical results from Monto Carlo simulations for the pure gauge system and for the system with gauge and quark fields are discussed. Numerical calculations for QCD require very substantial computational resources. The use of powerful vector processors of special purpose machines, in extending the scope and magnitude or the calculations is considered, and one may reasonably expect that in the near future good quantitative predictions will be obtained for QCD
Yunus, Abdul S; Govindarajan, Dhanasekaran; Huang, Zhuhui; Samal, Siba K
2003-05-01
We report here the nucleotide and deduced amino acid (aa) sequences of the small hydrophobic (SH) gene of the avian pneumovirus strain Colorado (APV/CO). The SH gene of APV/CO is 628 nucleotides in length from gene-start to gene-end. The longest ORF of the SH gene encoded a protein of 177 aas in length. Comparison of the deduced aa sequence of the SH protein of APV/CO with the corresponding published sequences of other members of genera metapneumovirus showed 28% identity with the newly discovered human metapneumovirus (hMPV), but no discernable identity with the APV subgroup A or B. Collectively, this data supports the hypothesis that: (i) APV/CO is distinct from European APV subgroups and belongs to the novel subgroup APV/C (APV/US); (ii) APV/CO is more closely related to hMPV, a mammalian metapneumovirus, than to either APV subgroup A or B. The SH gene of APV/CO was cloned using a genomic walk strategy which initiated cDNA synthesis from genomic RNA that traversed the genes in the order 3'-M-F-M2-SH-G-5', thus confirming that gene-order of APV/CO conforms in the genus Metapneumovirus. We also provide the sequences of transcription-signals and the M-F, F-M2, M2-SH and SH-G intergenic regions of APV/CO.
Methods for Melting Temperature Calculation
Hong, Qi-Jun
Melting temperature calculation has important applications in the theoretical study of phase diagrams and computational materials screenings. In this thesis, we present two new methods, i.e., the improved Widom's particle insertion method and the small-cell coexistence method, which we developed in order to capture melting temperatures both accurately and quickly. We propose a scheme that drastically improves the efficiency of Widom's particle insertion method by efficiently sampling cavities while calculating the integrals providing the chemical potentials of a physical system. This idea enables us to calculate chemical potentials of liquids directly from first-principles without the help of any reference system, which is necessary in the commonly used thermodynamic integration method. As an example, we apply our scheme, combined with the density functional formalism, to the calculation of the chemical potential of liquid copper. The calculated chemical potential is further used to locate the melting temperature. The calculated results closely agree with experiments. We propose the small-cell coexistence method based on the statistical analysis of small-size coexistence MD simulations. It eliminates the risk of a metastable superheated solid in the fast-heating method, while also significantly reducing the computer cost relative to the traditional large-scale coexistence method. Using empirical potentials, we validate the method and systematically study the finite-size effect on the calculated melting points. The method converges to the exact result in the limit of a large system size. An accuracy within 100 K in melting temperature is usually achieved when the simulation contains more than 100 atoms. DFT examples of Tantalum, high-pressure Sodium, and ionic material NaCl are shown to demonstrate the accuracy and flexibility of the method in its practical applications. The method serves as a promising approach for large-scale automated material screening in which
Development of My Footprint Calculator
Mummidisetti, Karthik
The Environmental footprint is a very powerful tool that helps an individual to understand how their everyday activities are impacting environmental surroundings. Data shows that global climate change, which is a growing concern for nations all over the world, is already affecting humankind, plants and animals through raising ocean levels, droughts & desertification and changing weather patterns. In addition to a wide range of policy measures implemented by national and state governments, it is necessary for individuals to understand the impact that their lifestyle may have on their personal environmental footprint, and thus over the global climate change. "My Footprint Calculator" (myfootprintcalculator.com) has been designed to be one the simplest, yet comprehensive, web tools to help individuals calculate and understand their personal environmental impact. "My Footprint Calculator" is a website that queries users about their everyday habits and activities and calculates their personal impact on the environment. This website was re-designed to help users determine their environmental impact in various aspects of their lives ranging from transportation and recycling habits to water and energy usage with the addition of new features that will allow users to share their experiences and their best practices with other users interested in reducing their personal Environmental footprint. The collected data is stored in the database and a future goal of this work plans to analyze the collected data from all users (anonymously) for developing relevant trends and statistics.
Calculations of nucleon structure functions
International Nuclear Information System (INIS)
Signal, A.I.
1990-01-01
We present a method of calculating deep inelastic nucleon structure functions using bag model wavefunctions. Our method uses the Peierls - Yoccoz projection to form translation invariant bag states. We obtain the correct support for the structure functions and satisfy the positivity requirements for quark and anti-quark distribution functions. (orig.)
Data Acquisition and Flux Calculations
DEFF Research Database (Denmark)
Rebmann, C.; Kolle, O; Heinesch, B
2012-01-01
In this chapter, the basic theory and the procedures used to obtain turbulent fluxes of energy, mass, and momentum with the eddy covariance technique will be detailed. This includes a description of data acquisition, pretreatment of high-frequency data and flux calculation....
Ab Initio Calculations of Oxosulfatovanadates
DEFF Research Database (Denmark)
Frøberg, Torben; Johansen, Helge
1996-01-01
Restricted Hartree-Fock and multi-configurational self-consistent-field calculations together with secondorder perturbation theory have been used to study the geometry, the electron density, and the electronicspectrum of (VO2SO4)-. A bidentate sulphate attachment to vanadium was found to be stabl...
Coil protection calculator for TFTR
International Nuclear Information System (INIS)
Marsala, R.J.; Lawson, J.E.; Persing, R.G.; Senko, T.R.; Woolley, R.D.
1989-01-01
A new coil protection system (CPS) is being developed to replace the existing TFTR magnetic coil fault detector. The existing fault detector sacrifices TFTR operating capability for simplicity. The new CPS, when installed in October of 1988, will permit operation up to the actual coil stress limits parameters in real-time. The computation will be done in a microprocessor based Coil Protection Calculator (CPC) currently under construction at PPL. THe new CPC will allow TFTR to operate with higher plasma currents and will permit the optimization of pulse repetition rates. The CPC will provide real-time estimates of critical coil and bus temperatures and stresses based on real-time redundant measurements of coil currents, coil cooling water inlet temperature, and plasma current. The critical parameter calculations are compared to prespecified limits. If these limits are reached or exceeded, protection action will be initiated to a hard wired control system (HCS), which will shut down the power supplies. The CPC consists of a redundant VME based microprocessor system which will sample all input data and compute all stress quantities every ten milliseconds. Thermal calculations will be approximated every 10ms with an exact solution occurring every second. The CPC features continuous cross-checking of redundant input signal, automatic detection of internal failure modes, monitoring and recording of calculated results, and a quick, functional verification of performance via an internal test system. (author)
Faas, S.; Snijders, Jaap; van Lenthe, J.H.; HernandezLaguna, A; Maruani, J; McWeeny, R; Wilson, S
2000-01-01
In this paper we present the first application of the ZORA (Zeroth Order Regular Approximation of the Dirac Fock equation) formalism in Ab Initio electronic structure calculations. The ZORA method, which has been tested previously in the context of Density Functional Theory, has been implemented in
Introduction to calculations of recuperators
International Nuclear Information System (INIS)
Dollar, M.
1977-01-01
Physical principles of heat transfer between fluid under turbulent flow conditions and a wall of a duct are described. The methods of calculations of heat transfer coefficient and the theory of recuperative heat exchangers are presented. Numerical examples are given to illustrate the theory. (author)
Photoproduction data for heating calculations
International Nuclear Information System (INIS)
Van der Marck, Steven C.; Koning, Arjan J.; Rochman, Dimitri
2008-01-01
For irradiations in a materials test reactor, the prediction of the amount of gamma heating in the reactor is important. Only a good predictive calculation will lead to an irradiation in which the specified temperatures are reached. The photons produced by fission product decay are often missing in spectrum calculations for a reactor, but the contribution of the photons can be computed effectively using engineering correlations for the amount of fission product decay and the ensuing photon spectrum. The prompt photons are usually calculated by a spectrum code based on the underlying nuclear data libraries. For most of the important nuclides, the nuclear data libraries contain data for the photon productions rates. However, there are still many nuclides for which the photon production data are missing, and some of these nuclides contribute to gamma heating. In this paper it is estimated what the contributions to heating are from photon production on nuclides such as 236 U, 238 Pu, 135 I, 135 Xe, 147 Pm, 148 Pm, 148m Pm, and 149 Sm. Also, simple arguments are given to judge the effect from photon production on all other (lumped) fission products, and from 28 Al decay. For all these calculations the High Flux Reactor is used as an example. (authors)
Methods for magnetostatic field calculation
International Nuclear Information System (INIS)
Vorozhtsov, S.B.
1984-01-01
Two methods for magnetostatic field calculation: differential and integrat are considered. Both approaches are shown to have certain merits and drawbacks, choice of the method depend on the type of the solved problem. An opportunity of combination of these tWo methods in one algorithm (hybrid method) is considered
Seaman, S. J.
2017-12-01
Water concentrations of clinopyroxene megacrysts in the Powai ankaramite flow, located near Mumbai, Deccan province, India, indicate that the parent magma of the flow hosted at least 4.3 wt.% water, an unusually high water concentration for a continental flood basalt magma. The Powai flow hosts clinopyroxene and olivine phenocrysts. Chatterjee and Sheth (2015) showed that phenocrysts in the flow were part of a cumulate layer intruded by basaltic melt at 6 kb and 1230oC, so the phenocrysts record characteristics of the cumulate parent melt. Clinopyroxene phenocrysts are oscillatorily zoned in water, Mg, Fe, and Ca concentrations, and have concentric bands 100-200 microns thick of 10-20 micron diameter melt inclusions. Olivine phenocrysts host only larger isolated melt inclusions. Zones in the cpx phenocrysts where melt inclusion-rich concentric bands occur have higher concentrations of water than inclusion-free zones. Water concentrations of cpx were used to calculate water concentrations in the melt from which the crystals formed using partition coefficients of Hauri et al. (2004). Water concentrations in the parent magma were between 4.3 and 8.2 wt. % based on water concentrations in cpx. Both Mg and Fe are relatively depleted in the water- and melt inclusion-rich zones in cpx, and Ca is enriched in these zones. Oscillatory zoning in cpx may be a result of repeated growth of cpx in water- richer and water-poorer boundary layers where water lowered melt viscosity and enhanced diffusion and crystal growth rates. Water-enhanced growth rates may have resulted in capture of melt inclusions preserved in water-rich cpx zones. Melt inclusions in olivine phenocrysts preserve lower water concentrations ( 1.2 wt. %) than those indicated by water concentration in cpx phenocrysts. This disparity may be evidence of water loss from melt inclusions in olivine (Gaetani et al., 2009) or may indicate that cpx and ol crystals did not crystallize from the same parent at the same time.
Yang, Changjun; Zhao, Biqiang; Zhu, Jie; Yue, Xinan; Wan, Weixing
2017-10-01
In this study we propose the combination of topside in-situ ion density data from the Communication/Navigation Outage Forecast System (C/NOFS) along with the electron density profile measurement from Constellation Observing System for Meteorology, Ionosphere & Climate (COSMIC) satellites Radio Occultation (RO) for studying the spatial and temporal variations of the ionospheric upper transition height (hT) and the oxygen ion (O+) density scale height. The latitudinal, local time and seasonal distributions of upper transition height show more consistency between hT re-calculated by the profile of the O+ using an α-Chapman function with linearly variable scale height and that determined from direct in-situ ion composition measurements, than with constant scale height and only the COSMIC data. The discrepancy in the values of hT between the C/NOFS measurement and that derived by the combination of COSMIC and C/NOFS satellites observations with variable scale height turns larger as the solar activity decreases, which suggests that the photochemistry and the electrodynamics of the equatorial ionosphere during the extreme solar minimum period produce abnormal structures in the vertical plasma distribution. The diurnal variation of scale heights (Hm) exhibits a minimum after sunrise and a maximum around noon near the geomagnetic equator. Further, the values of Hm exhibit a maximum in the summer hemisphere during daytime, whereas in the winter hemisphere the maximum is during night. Those features of Hm consistently indicate the prominent role of the vertical electromagnetic (E × B) drift in the equatorial ionosphere.
International Nuclear Information System (INIS)
Shapiro, S.D.; Endicott, S.K.; Province, M.A.; Pierce, J.A.; Campbell, E.J.
1991-01-01
Normal structure and function of the lung parenchyma depend upon elastic fibers. Amorphous elastin is biochemically stable in vitro, and may provide a metabolically stable structural framework for the lung parenchyma. To test the metabolic stability of elastin in the normal human lung parenchyma, we have (a) estimated the time elapsed since the synthesis of the protein through measurement of aspartic acid racemization and (b) modeled the elastin turnover through measurement of the prevalence of nuclear weapons-related 14 C. Elastin purified by a new technique from normal lung parenchyma was hydrolyzed; then the prevalences of D-aspartate and 14 C were measured by gas chromatography and accelerator-mass spectrometry, respectively. D-aspartate increased linearly with age; Kasp (1.76 x 10 - 3 yr - 1 ) was similar to that previously found for extraordinarily stable human tissues, indicating that the age of lung parenchymal elastin corresponded with the age of the subject. Radiocarbon prevalence data also were consistent with extraordinary metabolic stability of elastin; the calculated mean carbon residence time in elastin was 74 yr (95% confidence limits, 40-174 yr). These results indicate that airspace enlargement characteristic of 'aging lung' is not associated with appreciable new synthesis of lung parenchymal elastin. The present study provides the first tissue-specific evaluation of turnover of an extracellular matrix component in humans and underscores the potential importance of elastin for maintenance of normal lung structure. Most importantly, the present work provides a foundation for strategies to directly evaluate extracellular matrix injury and repair in diseases of lung (especially pulmonary emphysema), vascular tissue, and skin
Directory of Open Access Journals (Sweden)
J. R. Taylor
1996-09-01
Full Text Available The dynamic behaviour of the northern polar cap area is studied employing Northern Hemisphere electric potential patterns derived by the Assimilative Mapping of Ionospheric Electrodynamics (AMIE procedure. The rate of change in area of the polar cap, which can be defined as the region of magnetospheric field lines open to the interplanetary magnetic field (IMF, has been calculated during two intervals when the IMF had an approximately constant southward component (1100–2200 UT, 20 March 1990 and 1300–2100 UT, 21 March 1990. The estimates of the polar cap area are based on the approximation of the polar cap boundary by the flow reversal boundary. The change in the polar cap area is then compared to the predicted expansion rate based on a simple application of Faraday\\'s Law. Furthermore, timings of magnetospheric substorms are also related to changes in the polar cap area. Once the convection electric field reconfigures following a southward turning of the IMF, the growth rate of the observed polar cap boundary is consistent with that predicted by Faraday\\'s Law. A delay of typically 20 min to 50 min is observed between a substorm expansion phase onset and a reduction in the polar cap area. Such a delay is consistent with a synthesis between the near Earth neutral line and current disruption models of magnetospheric substorms in which the dipolarisation in the magnetotail may act as a trigger for reconnection. These delays may represent a propagation time between near geosynchronous orbit dipolarisation and subsequent reconnection further down tail. We estimate, from these delays, that the neutral X line occurs between ~35RE and ~75RE downstream in the tail.
Prenatal radiation exposure. Dose calculation
International Nuclear Information System (INIS)
Scharwaechter, C.; Schwartz, C.A.; Haage, P.; Roeser, A.
2015-01-01
The unborn child requires special protection. In this context, the indication for an X-ray examination is to be checked critically. If thereupon radiation of the lower abdomen including the uterus cannot be avoided, the examination should be postponed until the end of pregnancy or alternative examination techniques should be considered. Under certain circumstances, either accidental or in unavoidable cases after a thorough risk assessment, radiation exposure of the unborn may take place. In some of these cases an expert radiation hygiene consultation may be required. This consultation should comprise the expected risks for the unborn while not perturbing the mother or the involved medical staff. For the risk assessment in case of an in-utero X-ray exposition deterministic damages with a defined threshold dose are distinguished from stochastic damages without a definable threshold dose. The occurrence of deterministic damages depends on the dose and the developmental stage of the unborn at the time of radiation. To calculate the risks of an in-utero radiation exposure a three-stage concept is commonly applied. Depending on the amount of radiation, the radiation dose is either estimated, roughly calculated using standard tables or, in critical cases, accurately calculated based on the individual event. The complexity of the calculation thereby increases from stage to stage. An estimation based on stage one is easily feasible whereas calculations based on stages two and especially three are more complex and often necessitate execution by specialists. This article demonstrates in detail the risks for the unborn child pertaining to its developmental phase and explains the three-stage concept as an evaluation scheme. It should be noted, that all risk estimations are subject to considerable uncertainties.
Calculating zeros: Non-equilibrium free energy calculations
International Nuclear Information System (INIS)
Oostenbrink, Chris; Gunsteren, Wilfred F. van
2006-01-01
Free energy calculations on three model processes with theoretically known free energy changes have been performed using short simulation times. A comparison between equilibrium (thermodynamic integration) and non-equilibrium (fast growth) methods has been made in order to assess the accuracy and precision of these methods. The three processes have been chosen to represent processes often observed in biomolecular free energy calculations. They involve a redistribution of charges, the creation and annihilation of neutral particles and conformational changes. At very short overall simulation times, the thermodynamic integration approach using discrete steps is most accurate. More importantly, reasonable accuracy can be obtained using this method which seems independent of the overall simulation time. In cases where slow conformational changes play a role, fast growth simulations might have an advantage over discrete thermodynamic integration where sufficient sampling needs to be obtained at every λ-point, but only if the initial conformations do properly represent an equilibrium ensemble. From these three test cases practical lessons can be learned that will be applicable to biomolecular free energy calculations
Directory of Open Access Journals (Sweden)
Hayashizaki Yoshihide
2009-06-01
Full Text Available Abstract Background Wheat is an allopolyploid plant that harbors a huge, complex genome. Therefore, accumulation of expressed sequence tags (ESTs for wheat is becoming particularly important for functional genomics and molecular breeding. We prepared a comprehensive collection of ESTs from the various tissues that develop during the wheat life cycle and from tissues subjected to stress. We also examined their expression profiles in silico. As full-length cDNAs are indispensable to certify the collected ESTs and annotate the genes in the wheat genome, we performed a systematic survey and sequencing of the full-length cDNA clones. This sequence information is a valuable genetic resource for functional genomics and will enable carrying out comparative genomics in cereals. Results As part of the functional genomics and development of genomic wheat resources, we have generated a collection of full-length cDNAs from common wheat. By grouping the ESTs of recombinant clones randomly selected from the full-length cDNA library, we were able to sequence 6,162 independent clones with high accuracy. About 10% of the clones were wheat-unique genes, without any counterparts within the DNA database. Wheat clones that showed high homology to those of rice were selected in order to investigate their expression patterns in various tissues throughout the wheat life cycle and in response to abiotic-stress treatments. To assess the variability of genes that have evolved differently in wheat and rice, we calculated the substitution rate (Ka/Ks of the counterparts in wheat and rice. Genes that were preferentially expressed in certain tissues or treatments had higher Ka/Ks values than those in other tissues and treatments, which suggests that the genes with the higher variability expressed in these tissues is under adaptive selection. Conclusion We have generated a high-quality full-length cDNA resource for common wheat, which is essential for continuation of the
A T-matrix calculation for in-medium heavy-quark gluon scattering
International Nuclear Information System (INIS)
Huggins, K.; Rapp, R.
2012-01-01
The interactions of charm and bottom quarks in a quark-gluon plasma (QGP) are evaluated using a thermodynamic 2-body T-matrix. We specifically focus on heavy-quark (HQ) interactions with thermal gluons with an input potential motivated by lattice-QCD computations of the HQ free energy. The latter is implemented into a field-theoretic ansatz for color-Coulomb and (remnants of) confining interactions. This, in particular, enables to discuss corrections to the potential approach, specifically hard-thermal-loop corrections to the vertices, relativistic corrections deduced from pertinent Feynman diagrams, and a suitable projection on transverse thermal gluons. The resulting potentials are applied to compute scattering amplitudes in different color channels and utilized for a calculation of the corresponding HQ drag coefficient in the QGP. A factor of ∼2-3 enhancement over perturbative results is obtained, mainly driven by the resummation in the attractive color-channels.
Calculation of absorbed dose of anchorage-dependent cells from internal beta-rays irradiation
International Nuclear Information System (INIS)
Chen Jianwei; Huang Gang; Li Shijun
2001-01-01
Objective: To elicit the formula of internal dosimetry in anchorage-dependent cells by beta-emitting radionuclides from uniformly distributed volume sources. Methods: By means of the definition of absorbed dose and the MIRD (Medical International Radiation Dose) scheme the formula of internal dosimetry was reasonably deduced. Firstly, studying the systems of suspension culture cells. Then, taking account of the speciality of the systems of the anchorage-dependent cells and the directions of irradiation, the absorbed dose of anchorage -dependent cells was calculated by the accumulated radioactivity, beta-ray energy, and the volume of the cultured systems. Results: The formula of internal dosimetry of suspension culture cells and anchorage-dependent cells were achieved. At the same time, the formula of internal dosimetry of suspension culture cells was compared with that of MIRD and was confirmed accurate. Conclusion: The formula of internal dosimetry is concise, reliable and accurate
Mechanical calculation of heat exchangers
International Nuclear Information System (INIS)
Osweiller, Francis.
1977-01-01
Many heat exchangers are still being dimensioned at the present time by means of the American TEMA code (Tubular Exchanger Manufacturers Association). The basic formula of this code often gives rise to significant tubular plate thicknesses which, apart from the cost of materials, involve significant machining. Some constructors have brought into use calculation methods that are more analytic so as to take into better consideration the mechanical phenomena which come into play in a heat exchanger. After a brief analysis of these methods it is shown, how the original TEMA formulations have changed to reach the present version and how this code has incorporated Gardner's results for treating exchangers with two fixed heads. A formal and numerical comparison is then made of the analytical and TEMA methods by attempting to highlight a code based on these methods or a computer calculation programme in relation to the TEMA code [fr
CONTRIBUTION FOR MINING ATMOSPHERE CALCULATION
Directory of Open Access Journals (Sweden)
Franica Trojanović
1989-12-01
Full Text Available Humid air is an unavoidable feature of mining atmosphere, which plays a significant role in defining the climate conditions as well as permitted circumstances for normal mining work. Saturated humid air prevents heat conduction from the human body by means of evaporation. Consequently, it is of primary interest in the mining practice to establish the relative air humidity either by means of direct or indirect methods. Percentage of water in the surrounding air may be determined in various procedures including tables, diagrams or particular calculations, where each technique has its specific advantages and disadvantages. Classical calculation is done according to Sprung's formula, in which case partial steam pressure should also be taken from the steam table. The new method without the use of diagram or tables, established on the functional relation of pressure and temperature on saturated line, is presented here for the first time (the paper is published in Croatian.
The Collective Practice of Calculation
DEFF Research Database (Denmark)
Schrøder, Ida
The calculation of costs plays an increasingly large role in the decision-making processes of public sector human service organizations. This has brought scholars of management accounting to investigate the relationship between caring professions and demands to make economic entities of the service...... productions as either a process of hybridization or conflict. With these approaches, though, they fail to interrogate the possibility that professional action might not be either the one or the other, but entail a broad variety of relationships between calculations and judgements. This paper elaborates...... and judgement to reach decisions to invest in social services. The line is not drawn between the two, but between the material arrangements that make decisions possible. This implies that the insisting on qualitatively based decisions gives the professionals agency to collectively engage in practical...
Computer programs for lattice calculations
International Nuclear Information System (INIS)
Keil, E.; Reich, K.H.
1984-01-01
The aim of the workshop was to find out whether some standardisation could be achieved for future work in this field. A certain amount of useful information was unearthed, and desirable features of a ''standard'' program emerged. Progress is not expected to be breathtaking, although participants (practically from all interested US, Canadian and European accelerator laboratories) agreed that the mathematics of the existing programs is more or less the same. Apart from the NIH (not invented here) effect, there is a - to quite some extent understandable - tendency to stay with a program one knows and to add to it if unavoidable rather than to start using a new one. Users of the well supported program TRANSPORT (designed for beam line calculations) would prefer to have it fully extended for lattice calculations (to some extent already possible now), while SYNCH users wish to see that program provided with a user-friendly input, rather than spending time and effort for mastering a new program
Coil protection calculator for TFTR
International Nuclear Information System (INIS)
Marsala, R.J.; Woolley, R.D.
1987-01-01
A new coil protection calculator (CPC) is presented in this paper. It is now being developed for TFTR's magnetic field coils will replace the existing coil fault detector. The existing fault detector sacrifices TFTR operating capability for simplicity. The new CPC will permit operation up to the actual coil limits by accurately and continuously computing coil parameters in real-time. The improvement will allow TFTR to operate with higher plasma currents and will permit the optimization of pulse repetition rates
Rotor calculations for neutron spectroscopy
International Nuclear Information System (INIS)
Gobert, G.
1968-01-01
The determination of stress in a rotating disk plane of symmetry normal to the axis of rotation has been studied by a number of investigators. In a recent paper Reich gives an operating process for an analytical solution in an asymmetric rotating disk. In the report we give the calculation of finite difference stress solutions applicable to the two rotating disks. The equations are then programmed for the 360.75 computer by Fortran methods concerning the rotors of choppers. (author) [fr
Rontogianni, S.; Konstantinou, K. I.; Evangelidis, C.; Melis, N. S.
2011-12-01
The Gulf of Gökova is located in the southeast Aegean along the coast of the southwest Anatolia. It is surrounded by the Bodrum Peninsula to the north, Datça Peninsula to the south and the island of Kos to the west. The Gulf is under a N-S regional extensional tectonic regime related to the westerly escape of the Anatolian plate, as a result of the collision of the Arab-African and Eurasian plates. Multi-channel seismic reflection studies that took place in the area revealed a E-W trending buried listric normal fault to the south of the Gulf, the Datça Fault, the associated antithetic faults in the north of the Gulf and a younger NE active fault, named Gökova Tranfer Fault (GTF), in the central part of the Gulf. According to these studies, the activity of the Datça Fault has been decelerated, possibly since Pleistocene, while the continuing extension has been taken up by the faults in the northeast margin of the Gulf. For our analysis we selected all the shallow earthquake activity that took place in the Gulf, within the time window from 2002 to 2011 as provided by the two seismological centers NOA-IG (HL) and KOERI-NEMC (KO). We used data from 15 three component seismic stations surrounding the Gulf. This seismic activity is observed within three periods: (a) November 2002 - May 2003, (b) May 2004 - end of 2007 and (c) December 2008 - May 2011. The strongest events recorded took place in January 2005 and May 2011, with local magnitudes ML 5.1 and 4.9 respectively. After a thorough quality control, a dataset of 192 seismic events was selected, with criteria that at least 4P and 3S phases were available. Manually picked arrival times for these selected events were inverted in order to obtain a 1D velocity model with station corrections. Probabilistic nonlinear earthquake locations were calculated using this newly derived velocity model. The earthquake locations showed that the seismic activity extends from the island of Kos to the center of the Gulf, mainly
Parallel plasma fluid turbulence calculations
International Nuclear Information System (INIS)
Leboeuf, J.N.; Carreras, B.A.; Charlton, L.A.; Drake, J.B.; Lynch, V.E.; Newman, D.E.; Sidikman, K.L.; Spong, D.A.
1994-01-01
The study of plasma turbulence and transport is a complex problem of critical importance for fusion-relevant plasmas. To this day, the fluid treatment of plasma dynamics is the best approach to realistic physics at the high resolution required for certain experimentally relevant calculations. Core and edge turbulence in a magnetic fusion device have been modeled using state-of-the-art, nonlinear, three-dimensional, initial-value fluid and gyrofluid codes. Parallel implementation of these models on diverse platforms--vector parallel (National Energy Research Supercomputer Center's CRAY Y-MP C90), massively parallel (Intel Paragon XP/S 35), and serial parallel (clusters of high-performance workstations using the Parallel Virtual Machine protocol)--offers a variety of paths to high resolution and significant improvements in real-time efficiency, each with its own advantages. The largest and most efficient calculations have been performed at the 200 Mword memory limit on the C90 in dedicated mode, where an overlap of 12 to 13 out of a maximum of 16 processors has been achieved with a gyrofluid model of core fluctuations. The richness of the physics captured by these calculations is commensurate with the increased resolution and efficiency and is limited only by the ingenuity brought to the analysis of the massive amounts of data generated
Microcomputer generated pipe support calculations
International Nuclear Information System (INIS)
Hankinson, R.F.; Czarnowski, P.; Roemer, R.E.
1991-01-01
The cost and complexity of pipe support design has been a continuing challenge to the construction and modification of commercial nuclear facilities. Typically, pipe support design or qualification projects have required large numbers of engineers centrally located with access to mainframe computer facilities. Much engineering time has been spent repetitively performing a sequence of tasks to address complex design criteria and consolidating the results of calculations into documentation packages in accordance with strict quality requirements. The continuing challenges of cost and quality, the need for support engineering services at operating plant sites, and the substantial recent advances in microcomputer systems suggested that a stand-alone microcomputer pipe support calculation generator was feasible and had become a necessity for providing cost-effective and high quality pipe support engineering services to the industry. This paper outlines the preparation for, and the development of, an integrated pipe support design/evaluation software system which maintains all computer programs in the same environment, minimizes manual performance of standard or repetitive tasks, and generates a high quality calculation which is consistent and easily followed
Calculational methods for lattice cells
International Nuclear Information System (INIS)
Askew, J.R.
1980-01-01
At the current stage of development, direct simulation of all the processes involved in the reactor to the degree of accuracy required is not an economic proposition, and this is achieved by progressive synthesis of models for parts of the full space/angle/energy neutron behaviour. The split between reactor and lattice calculations is one such simplification. Most reactors are constructed of repetitions of similar geometric units, the fuel elements, having broadly similar properties. Thus the provision of detailed predictions of their behaviour is an important step towards overall modelling. We shall be dealing with these lattice methods in this series of lectures, but will refer back from time to time to their relationship with overall reactor calculation The lattice cell is itself composed of somewhat similar sub-units, the fuel pins, and will itself often rely upon a further break down of modelling. Construction of a good model depends upon the identification, on physical and mathematical grounds, of the most helpful division of the calculation at this level
Calculation of groundwater travel time
International Nuclear Information System (INIS)
Arnett, R.C.; Sagar, B.; Baca, R.G.
1984-12-01
Pre-waste-emplacement groundwater travel time is one indicator of the isolation capability of the geologic system surrounding a repository. Two distinct modeling approaches exist for prediction of groundwater flow paths and travel times from the repository location to the designated accessible environment boundary. These two approaches are: (1) the deterministic approach which calculates a single value prediction of groundwater travel time based on average values for input parameters and (2) the stochastic approach which yields a distribution of possible groundwater travel times as a function of the nature and magnitude of uncertainties in the model inputs. The purposes of this report are to (1) document the theoretical (i.e., mathematical) basis used to calculate groundwater pathlines and travel times in a basalt system, (2) outline limitations and ranges of applicability of the deterministic modeling approach, and (3) explain the motivation for the use of the stochastic modeling approach currently being used to predict groundwater pathlines and travel times for the Hanford Site. Example calculations of groundwater travel times are presented to highlight and compare the differences between the deterministic and stochastic modeling approaches. 28 refs
Clouvas, A; Antonopoulos-Domis, M; Silva, J
2000-01-01
The dose rate conversion factors D/sub CF/ (absorbed dose rate in air per unit activity per unit of soil mass, nGy h/sup -1/ per Bq kg/sup -1/) are calculated 1 m above ground for photon emitters of natural radionuclides uniformly distributed in the soil. Three Monte Carlo codes are used: 1) The MCNP code of Los Alamos; 2) The GEANT code of CERN; and 3) a Monte Carlo code developed in the Nuclear Technology Laboratory of the Aristotle University of Thessaloniki. The accuracy of the Monte Carlo results is tested by the comparison of the unscattered flux obtained by the three Monte Carlo codes with an independent straightforward calculation. All codes and particularly the MCNP calculate accurately the absorbed dose rate in air due to the unscattered radiation. For the total radiation (unscattered plus scattered) the D/sub CF/ values calculated from the three codes are in very good agreement between them. The comparison between these results and the results deduced previously by other authors indicates a good ag...
Wave resistance calculation method combining Green functions based on Rankine and Kelvin source
Directory of Open Access Journals (Sweden)
LI Jingyu
2017-12-01
Full Text Available [Ojectives] At present, the Boundary Element Method(BEM of wave-making resistance mostly uses a model in which the velocity distribution near the hull is solved first, and the pressure integral is then calculated using the Bernoulli equation. However,the process of this model of wave-making resistance is complex and has low accuracy.[Methods] To address this problem, the present paper deduces a compound method for the quick calculation of ship wave resistance using the Rankine source Green function to solve the hull surface's source density, and combining the Lagally theorem concerning source point force calculation based on the Kelvin source Green function so as to solve the wave resistance. A case for the Wigley model is given.[Results] The results show that in contrast to the thin ship method of the linear wave resistance theorem, this method has higher precision, and in contrast to the method which completely uses the Kelvin source Green function, this method has better computational efficiency.[Conclusions] In general, the algorithm in this paper provides a compromise between precision and efficiency in wave-making resistance calculation.
The nuclear deformation versus spin-flip like excitations and the suppression of the 2νββ amplitude
International Nuclear Information System (INIS)
Raduta, A.A.; Delion, D.S.; Faessler, Amand
1997-01-01
We were the first who investigated the influence of spin-flip and non-spin-flip configuration on the separation of the transition amplitude of the Gamow-Teller double beta decay. A realistic Hamiltonian and a projected spherical single particle basis is considered, while the effects are generated by three antagonistic sources: spin-flip, non-spin-flip like excitation and nuclear deformation. Moreover, by a smooth variation of a deformation parameter one could bridge the spherical and deformed pictures. Although our application is not aimed at describing the experimental situation we chose as input data those corresponding to the transition 82 Se → 82 Kr. For near spherical case there are two resonances in M GT , one having a spin-flip structure and identified as GT resonance and one of non-spin-flip structure, placed at low energy. For large deformation and vanishing g pp coupling constant there are two resonances of spin-flip and non-spin-flip natures (ΔI = 1 and 0, respectively) and located at the same energy, what indicates that the deformation acts against the separation of this resonances. In conclusion, our calculation showed that the mechanism of M GT suppression is different for spherical and deformed nuclei. In both cases approaching the critical value of g pp where the RPA breaks down, a lot of strength is accumulated in lowest RPA state and, while in the spherical case this has a non spin-flip nature, in the deformed case the state is a mixture of both types of configurations
Energy Technology Data Exchange (ETDEWEB)
Nakata, Hidehiko [Waseda Univ., Tokyo (Japan). Dept. of Physics; Tachibana, Takahiro; Yamada, Masami
1997-03-01
Recently the gross theory of nuclear {beta}-decay was refined for odd-odd nuclei. In this refinement, the effect of the selection rule of {beta}-transitions from the ground states of odd-odd nuclei to those of even-even nuclei was taken into account based on a statistical consideration. The transitions to the first 2{sup +} excited states in even-even nuclei were also taken into account according to the selection rule approximately. In that study, it was found that the transitions between 1{sup -} ground states of the odd-odd nuclei and 0{sup +} ground states of even-even nuclei, belonging to the first-forbidden transitions of rank 1, are strongly hindered. A reduction factor was introduced for the transitions to the ground states of even-even nuclei to take into account this hindrance. It was also found that the strength functions of the Gamow-Teller transitions obtained from the conventional gross theory are underestimated by a factor of about 3. In order to improve this underestimation, the Lorentz-type function was adopted for the one-particle strength function in the model instead of the hyperbolic-secant-type function. In the present study we have newly analyzed the experimental ft-values of odd-A nuclei, and found that the first-forbidden transitions of rank 1 are also considerably hindered between the ground states. Following the above refinement we have calculated the {beta}-ray spectra of some odd-odd short-lived fission products with the use of the refined gross theory. These results are compared not only with the experiments by Rudstam et al. but also with the conventional gross theory. (author)
International Nuclear Information System (INIS)
Celikovic, Igor
2013-01-01
In this thesis we investigated the structure of nuclei around 68 Ni as well as the production, separation and identification of proton-rich isotopes lying in the vicinity of the doubly-magic 100 Sn nucleus.In the first part, we discuss the evolution of collectivity and the interplay between collective and single-particle degrees of freedom in nuclei around 68 Ni. We measured lifetimes in Zn isotopes around N = 40 produced in 238 U + 70 Zn deep-inelastic collisions at GANIL. We used a plunger device and the recoil-distance Doppler-shift method. The nuclei of interest were identified by the VAMOS spectrometer and the γ-rays with the EXOGAM array. The reduced electromagnetic transitions probabilities were extracted from the lifetimes. Several transitions and lifetimes are reported for the first time. The experimental results are discussed in the framework of shell model calculations. In the second part, the partial conservation of seniority in the g 9/2 shell and its influence on one-particle transfer is discussed. The third part presents the analysis of an in-beam test performed at RIKEN (Japan) to evaluate two settings of the BigRIPS separator for optimizing the production and selection of 100 Sn. This study has been used to setup our subsequent experiment, dedicated to the measurement of the Gamow-Teller strength in the decay of 100 Sn, to the mapping of the proton drip-line and the study of short-lived isomers in this mass region. Nuclei around 100 Sn were produced by fragmentation of a 345 MeV/u 124 Xe beam on a Be target. The production cross-sections of nuclei around 100 Sn were measured. The search for new isotopes and new isomers in all identified nuclei is presented. (author) [fr
Minimal nuclear energy density functional
Bulgac, Aurel; Forbes, Michael McNeil; Jin, Shi; Perez, Rodrigo Navarro; Schunck, Nicolas
2018-04-01
We present a minimal nuclear energy density functional (NEDF) called "SeaLL1" that has the smallest number of possible phenomenological parameters to date. SeaLL1 is defined by seven significant phenomenological parameters, each related to a specific nuclear property. It describes the nuclear masses of even-even nuclei with a mean energy error of 0.97 MeV and a standard deviation of 1.46 MeV , two-neutron and two-proton separation energies with rms errors of 0.69 MeV and 0.59 MeV respectively, and the charge radii of 345 even-even nuclei with a mean error ɛr=0.022 fm and a standard deviation σr=0.025 fm . SeaLL1 incorporates constraints on the equation of state (EoS) of pure neutron matter from quantum Monte Carlo calculations with chiral effective field theory two-body (NN ) interactions at the next-to-next-to-next-to leading order (N3LO) level and three-body (NNN ) interactions at the next-to-next-to leading order (N2LO) level. Two of the seven parameters are related to the saturation density and the energy per particle of the homogeneous symmetric nuclear matter, one is related to the nuclear surface tension, two are related to the symmetry energy and its density dependence, one is related to the strength of the spin-orbit interaction, and one is the coupling constant of the pairing interaction. We identify additional phenomenological parameters that have little effect on ground-state properties but can be used to fine-tune features such as the Thomas-Reiche-Kuhn sum rule, the excitation energy of the giant dipole and Gamow-Teller resonances, the static dipole electric polarizability, and the neutron skin thickness.
Cyclotron based nuclear science: Progress report, April 1, 1986-March 31, 1987
International Nuclear Information System (INIS)
1987-08-01
This report contains descriptions of research programs at the Institute, progress on construction of the K500 cyclotron, and descriptions of new experimental devices being built to take advantage of new beams that will be available. Several milestones were reached in construction of the new cyclotron during the period. In early summer, 1986, the magnet was completed with all trim coils and shimming iron in place. During July and August, the final field maps were made, which will be used for calculations of run parameters. In the spring, one rf amplifier was completed and tested over the full frequency and power range. Also in the spring, the computer control system successfully operated positioning controls and trim coil power supplies. Final assembly of the rf system including the dees, resonators and other 2 rf amplifiers is now underway. Initial attempts at getting beam are expected in September. The design of the ECR source was completed in the fall. A beam line configuration has been designed for the K500 cyclotron which will result initially in 3 lines, with a fourth to be added in 1988. With the eminent completion of the K500, there has been considerable instrumentation development. A 4π neutron calorimeter is under construction for heavy ion reaction studies, construction is beginning on a proton spectrometer for studies of Gamow-Teller matrix elements with the (d, 2 He) reaction, and several detector systems are being developed. During the year, the 88 inch cyclotron operated 4845 hours for research and beam development. Research programs in nuclear science scheduled 57% of the time. Atomic physics programs used 19% of the time, and a program in trace analysis scheduled 6%. An industrial testing laboratory used 18 hours. The remainder of the time was used for beam development, primarily for increasing the energy and/or intensity of heavy ion beams
Nuclear data library in design calculation
International Nuclear Information System (INIS)
Hirano, Go; Kosaka, Shinya
2006-01-01
In core design calculation, nuclear data takes part as multi group cross section library during the assembly calculation, which is the first stage of a core design calculation. This report summarizes the multi group cross section libraries used in assembly calculations and also presents the methods adopted for resonance and assembly calculation. (author)
Calculation of gas turbine characteristic
Mamaev, B. I.; Murashko, V. L.
2016-04-01
The reasons and regularities of vapor flow and turbine parameter variation depending on the total pressure drop rate π* and rotor rotation frequency n are studied, as exemplified by a two-stage compressor turbine of a power-generating gas turbine installation. The turbine characteristic is calculated in a wide range of mode parameters using the method in which analytical dependences provide high accuracy for the calculated flow output angle and different types of gas dynamic losses are determined with account of the influence of blade row geometry, blade surface roughness, angles, compressibility, Reynolds number, and flow turbulence. The method provides satisfactory agreement of results of calculation and turbine testing. In the design mode, the operation conditions for the blade rows are favorable, the flow output velocities are close to the optimal ones, the angles of incidence are small, and the flow "choking" modes (with respect to consumption) in the rows are absent. High performance and a nearly axial flow behind the turbine are obtained. Reduction of the rotor rotation frequency and variation of the pressure drop change the flow parameters, the parameters of the stages and the turbine, as well as the form of the characteristic. In particular, for decreased n, nonmonotonic variation of the second stage reactivity with increasing π* is observed. It is demonstrated that the turbine characteristic is mainly determined by the influence of the angles of incidence and the velocity at the output of the rows on the losses and the flow output angle. The account of the growing flow output angle due to the positive angle of incidence for decreased rotation frequencies results in a considerable change of the characteristic: poorer performance, redistribution of the pressure drop at the stages, and change of reactivities, growth of the turbine capacity, and change of the angle and flow velocity behind the turbine.
Calculation of Rydberg interaction potentials
DEFF Research Database (Denmark)
Weber, Sebastian; Tresp, Christoph; Menke, Henri
2017-01-01
The strong interaction between individual Rydberg atoms provides a powerful tool exploited in an ever-growing range of applications in quantum information science, quantum simulation and ultracold chemistry. One hallmark of the Rydberg interaction is that both its strength and angular dependence...... for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up...
FIPRED Project - Experiments and calculations
International Nuclear Information System (INIS)
Ohai, D.; Dumitrescu, I.; Doca, C.; Meleg, T.; Benga, D.
2009-01-01
Full text: The FIPRED (Fission Products Release from Debris Bed) Project was developed by INR in the framework of EC FP6 SARNET (2004-2008) and will be continued in EC FP6 SARNET2 (2009-2013). The project objective is the evaluation of fission product release from debris bed resulted after reactor severe accident by natural UO 2 sintered pellets self disintegration by oxidation. A large experimental program was performed covering the main parameters influencing granulometric distribution of powders (fragments) resulted from UO 2 sintered pellets self disintegration by air oxidation. The paper presents experimental results obtained and material equation obtained by mathematical calculations. (authors)
The Dental Trauma Internet Calculator
DEFF Research Database (Denmark)
Gerds, Thomas Alexander; Lauridsen, Eva Fejerskov; Christensen, Søren Steno Ahrensburg
2012-01-01
Background/Aim Prediction tools are increasingly used to inform patients about the future dental health outcome. Advanced statistical methods are required to arrive at unbiased predictions based on follow-up studies. Material and Methods The Internet risk calculator at the Dental Trauma Guide...... provides prognoses for teeth with traumatic injuries based on the Copenhagen trauma database: http://www.dentaltraumaguide.org The database includes 2191 traumatized permanent teeth from 1282 patients that were treated at the dental trauma unit at the University Hospital in Copenhagen (Denmark...
Perturbation calculations with Wilson loop
International Nuclear Information System (INIS)
Peixoto Junior, L.B.
1984-01-01
We present perturbative calculations with the Wilson loop (WL). The dimensional regularization method is used with a special attention concerning to the problem of divergences in the WL expansion in second and fourth orders, in three and four dimensions. We show that the residue in the pole, in 4d, of the fourth order graphs contribution sum is important for the charge renormalization. We compute up to second order the exact expression of the WL, in three-dimensional gauge theories with topological mass as well as its assimptotic behaviour for small and large distances. the author [pt
Symmetries applied to reactor calculations
International Nuclear Information System (INIS)
Makai, M.
1982-03-01
Three problems of a reactor-calculational model are discussed with the help of symmetry considerations. 1/ A coarse mesh method applicable to any geometry is derived. It is shown that the coarse mesh solution can be constructed from a few standard boundary value problems. 2/ A second stage homogenization method is given based on the Bloch theorem. This ensures the continuity of the current and the flux at the boundary. 3/ The validity of the micro-macro separation is shown for heterogeneous lattices. A formula for the neutron density is derived for cell homogenization. (author)
Criticality calculations for safety analysis
International Nuclear Information System (INIS)
Vellozo, S.O.
1981-01-01
Criticality studies in uranium nitrate and plutonium nitrate aqueous solutions were done. For uranium compound three basic computer codes are used: GAMTEC-II, DTF-IV, KENO-IV. Water was used as refletor and the results obtained with the different computer codes were analyzed and compared with the 'Handbuck zur Kriticalitat'. The cross sections and the cylindrical geometry were generated by Gamtec-II computer code. In the second compound the thickness of the recipient with plutonium nitrate are used with rectangular geometry and concret reflector. The effective multiplication constant was calculated with the Gamtec-II and Keno-IV library. The results show many differences. (E.G) [pt
Calculable resistors of coaxial design
International Nuclear Information System (INIS)
Kucera, J; Vollmer, E; Schurr, J; Bohacek, J
2009-01-01
1000 Ω and 1290.64 Ω coaxial resistors with calculable frequency dependence have been realized at PTB to be used in quantum Hall effect-based impedance measurements. In contradistinction to common designs of coaxial resistors, the design described in this paper makes it possible to remove the resistive element from the shield and to handle it without cutting the outer cylindrical shield of the resistor. Emphasis has been given to manufacturing technology and suppressing unwanted sources of frequency dependence. The adjustment accuracy is better than 10 µΩ Ω −1
Radiation shielding calculation using MCNP
International Nuclear Information System (INIS)
Masukawa, Fumihiro
2001-01-01
To verify the Monte Carlo code MCNP4A as a tool to generate the reference data in the shielding designs and the safety evaluations, various shielding benchmark experiments were analyzed using this code. These experiments were categorized in three types of the shielding subjects; bulk shielding, streaming, and skyshine. For the variance reduction technique, which is indispensable to get meaningful results with the Monte Carlo shielding calculation, we mainly used the weight window, the energy dependent Russian roulette and spitting. As a whole, our analyses performed enough small statistical errors and showed good agreements with these experiments. (author)
Techniques of nuclear structure calculations
International Nuclear Information System (INIS)
Dyson, R.D.
1967-04-01
The quasiparticle method for identical particles interacting through pairing forces has been extended by others for use with systems of neutrons and protons. The method is to project isospin from separately considered neutron and proton quasiparticle wavefunctions. This is discussed in detail, and it seems that the projection may not be important. Therefore unprojected quasiparticle wavefunctions are tried with some success as a basis of states in which to diagonalize a realistic nuclear Hamiltonian. Brief unrelated calculations on nuclei of mass 19 and the SU(3) classification of states in the p-f shell are also presented. (author)
Neutronic calculation of reactor cells
International Nuclear Information System (INIS)
Jaliff, J.O.
1981-01-01
Multigroup calculations of cylindrical pin cells were programmed, in Fortran IV, upon the basis of collision probabilities in each energy group. A rational approximation to the fuel-to-fuel collision probability in resonance groups was used. Together with the intermediate resonance theory, cross sections corrected for heterogeneity and absorber interactions were found. For the optimization of the program, the cell of a BWR reactor was taken as reference. Data for such a cell and the reactor's operating conditions are presented. PINCEL is a fast and flexible program, with checked results, around a 69-group library. (M.E.L.) [es
Electronics reliability calculation and design
Dummer, Geoffrey W A; Hiller, N
1966-01-01
Electronics Reliability-Calculation and Design provides an introduction to the fundamental concepts of reliability. The increasing complexity of electronic equipment has made problems in designing and manufacturing a reliable product more and more difficult. Specific techniques have been developed that enable designers to integrate reliability into their products, and reliability has become a science in its own right. The book begins with a discussion of basic mathematical and statistical concepts, including arithmetic mean, frequency distribution, median and mode, scatter or dispersion of mea
Digital calculations of engine cycles
Starkman, E S; Taylor, C Fayette
1964-01-01
Digital Calculations of Engine Cycles is a collection of seven papers which were presented before technical meetings of the Society of Automotive Engineers during 1962 and 1963. The papers cover the spectrum of the subject of engine cycle events, ranging from an examination of composition and properties of the working fluid to simulation of the pressure-time events in the combustion chamber. The volume has been organized to present the material in a logical sequence. The first two chapters are concerned with the equilibrium states of the working fluid. These include the concentrations of var
Methods for calculating nonconcave entropies
International Nuclear Information System (INIS)
Touchette, Hugo
2010-01-01
Five different methods which can be used to analytically calculate entropies that are nonconcave as functions of the energy in the thermodynamic limit are discussed and compared. The five methods are based on the following ideas and techniques: (i) microcanonical contraction, (ii) metastable branches of the free energy, (iii) generalized canonical ensembles with specific illustrations involving the so-called Gaussian and Betrag ensembles, (iv) the restricted canonical ensemble, and (v) the inverse Laplace transform. A simple long-range spin model having a nonconcave entropy is used to illustrate each method
FRELIB, Failure Reliability Index Calculation
International Nuclear Information System (INIS)
Parkinson, D.B.; Oestergaard, C.
1984-01-01
1 - Description of problem or function: Calculation of the reliability index given the failure boundary. A linearization point (design point) is found on the failure boundary for a stationary reliability index (min) and a stationary failure probability density function along the failure boundary, provided that the basic variables are normally distributed. 2 - Method of solution: Iteration along the failure boundary which must be specified - together with its partial derivatives with respect to the basic variables - by the user in a subroutine FSUR. 3 - Restrictions on the complexity of the problem: No distribution information included (first-order-second-moment-method). 20 basic variables (could be extended)
Iron -chromium alloys and free surfaces: from ab initio calculations to thermodynamic modeling
International Nuclear Information System (INIS)
Levesque, M.
2010-11-01
Ferritic steels possibly strengthened by oxide dispersion are candidates as structural materials for generation IV and fusion nuclear reactors. Their use is limited by incomplete knowledge of the iron-chromium phase diagram at low temperatures and of the phenomena inducing preferential segregation of one element at grain boundaries or at surfaces. In this context, this work contributes to the multi-scale study of the model iron-chromium alloy and their free surfaces by numerical simulations. This study begins with ab initio calculations of properties related to the mixture of atoms of iron and chromium. We highlight complex dependency of the magnetic moments of the chromium atoms on their local chemical environment. Surface properties are also proving sensitive to magnetism. This is the case of impurity segregation of chromium in iron and of their interactions near the surface. In a second step, we construct a simple energy model for high numerical efficiency. It is based on pair interactions on a rigid lattice to which are given local chemical environment and temperature dependencies. With this model, we reproduce the ab initio results at zero temperature and experimental results at high temperature. We also deduce the solubility limits at all intermediate temperatures with mean field approximations that we compare to Monte Carlo simulations. The last step of our work is to introduce free surfaces in our model. We then study the effect of ab initio calculated bulk and surface properties on surface segregation.Finally, we calculate segregation isotherms. We therefore propose an evolution model of surface composition of iron-chromium alloys as a function of bulk composition. which are given local chemical environment and temperature dependencies. With this model, we reproduce the ab initio results at zero temperature and experimental results at high temperature. We also deduce the solubility limits at all intermediate temperatures with mean field approximations that
Calculational Tool for Skin Contamination Dose Assessment
Hill, R L
2002-01-01
Spreadsheet calculational tool was developed to automate the calculations preformed for dose assessment of skin contamination. This document reports on the design and testing of the spreadsheet calculational tool.
Dissecting Reactor Antineutrino Flux Calculations
Sonzogni, A. A.; McCutchan, E. A.; Hayes, A. C.
2017-09-01
Current predictions for the antineutrino yield and spectra from a nuclear reactor rely on the experimental electron spectra from 235U, 239Pu, 241Pu and a numerical method to convert these aggregate electron spectra into their corresponding antineutrino ones. In the present work we investigate quantitatively some of the basic assumptions and approximations used in the conversion method, studying first the compatibility between two recent approaches for calculating electron and antineutrino spectra. We then explore different possibilities for the disagreement between the measured Daya Bay and the Huber-Mueller antineutrino spectra, including the 238U contribution as well as the effective charge and the allowed shape assumption used in the conversion method. We observe that including a shape correction of about +6 % MeV-1 in conversion calculations can better describe the Daya Bay spectrum. Because of a lack of experimental data, this correction cannot be ruled out, concluding that in order to confirm the existence of the reactor neutrino anomaly, or even quantify it, precisely measured electron spectra for about 50 relevant fission products are needed. With the advent of new rare ion facilities, the measurement of shape factors for these nuclides, for many of which precise beta intensity data from TAGS experiments already exist, would be highly desirable.
NATIONAL STORMWATER CALCULATOR USER'S GUIDE ...
The National Stormwater Calculator is a simple to use tool for computing small site hydrology for any location within the US. It estimates the amount of stormwater runoff generated from a site under different development and control scenarios over a long term period of historical rainfall. The analysis takes into account local soil conditions, slope, land cover and meteorology. Different types of low impact development (LID) practices (also known as green infrastructure) can be employed to help capture and retain rainfall on-site. Future climate change scenarios taken from internationally recognized climate change projections can also be considered. The calculator provides planning level estimates of capital and maintenance costs which will allow planners and managers to evaluate and compare effectiveness and costs of LID controls.The calculator’s primary focus is informing site developers and property owners on how well they can meet a desired stormwater retention target. It can be used to answer such questions as:• What is the largest daily rainfall amount that can be captured by a site in either its pre-development, current, or post-development condition?• To what degree will storms of different magnitudes be captured on site?• What mix of LID controls can be deployed to meet a given stormwater retention target?• How well will LID controls perform under future meteorological projections made by global climate change models?• What are the relativ
Adjoint electron Monte Carlo calculations
International Nuclear Information System (INIS)
Jordan, T.M.
1986-01-01
Adjoint Monte Carlo is the most efficient method for accurate analysis of space systems exposed to natural and artificially enhanced electron environments. Recent adjoint calculations for isotropic electron environments include: comparative data for experimental measurements on electronics boxes; benchmark problem solutions for comparing total dose prediction methodologies; preliminary assessment of sectoring methods used during space system design; and total dose predictions on an electronics package. Adjoint Monte Carlo, forward Monte Carlo, and experiment are in excellent agreement for electron sources that simulate space environments. For electron space environments, adjoint Monte Carlo is clearly superior to forward Monte Carlo, requiring one to two orders of magnitude less computer time for relatively simple geometries. The solid-angle sectoring approximations used for routine design calculations can err by more than a factor of 2 on dose in simple shield geometries. For critical space systems exposed to severe electron environments, these potential sectoring errors demand the establishment of large design margins and/or verification of shield design by adjoint Monte Carlo/experiment
Dispersion relations in loop calculations
International Nuclear Information System (INIS)
Kniehl, B.A.
1996-01-01
These lecture notes give a pedagogical introduction to the use of dispersion relations in loop calculations. We first derive dispersion relations which allow us to recover the real part of a physical amplitude from the knowledge of its absorptive part along the branch cut. In perturbative calculations, the latter may be constructed by means of Cutkosky's rule, which is briefly discussed. For illustration, we apply this procedure at one loop to the photon vacuum-polarization function induced by leptons as well as to the γf anti-f vertex form factor generated by the exchange of a massive vector boson between the two fermion legs. We also show how the hadronic contribution to the photon vacuum polarization may be extracted from the total cross section of hadron production in e + e - annihilation measured as a function of energy. Finally, we outline the application of dispersive techniques at the two-loop level, considering as an example the bosonic decay width of a high-mass Higgs boson. (author)
Neutronics calculation of RTP core
Rabir, Mohamad Hairie B.; Zin, Muhammad Rawi B. Mohamed; Karim, Julia Bt. Abdul; Bayar, Abi Muttaqin B. Jalal; Usang, Mark Dennis Anak; Mustafa, Muhammad Khairul Ariff B.; Hamzah, Na'im Syauqi B.; Said, Norfarizan Bt. Mohd; Jalil, Muhammad Husamuddin B.
2017-01-01
Reactor calculation and simulation are significantly important to ensure safety and better utilization of a research reactor. The Malaysian's PUSPATI TRIGA Reactor (RTP) achieved initial criticality on June 28, 1982. The reactor is designed to effectively implement the various fields of basic nuclear research, manpower training, and production of radioisotopes. Since early 90s, neutronics modelling were used as part of its routine in-core fuel management activities. The are several computer codes have been used in RTP since then, based on 1D neutron diffusion, 2D neutron diffusion and 3D Monte Carlo neutron transport method. This paper describes current progress and overview on neutronics modelling development in RTP. Several important parameters were analysed such as keff, reactivity, neutron flux, power distribution and fission product build-up for the latest core configuration. The developed core neutronics model was validated by means of comparison with experimental and measurement data. Along with the RTP core model, the calculation procedure also developed to establish better prediction capability of RTP's behaviour.
Calculation of sound propagation in fibrous materials
DEFF Research Database (Denmark)
Tarnow, Viggo
1996-01-01
Calculations of attenuation and velocity of audible sound waves in glass wools are presented. The calculations use only the diameters of fibres and the mass density of glass wools as parameters. The calculations are compared with measurements.......Calculations of attenuation and velocity of audible sound waves in glass wools are presented. The calculations use only the diameters of fibres and the mass density of glass wools as parameters. The calculations are compared with measurements....
SR 97 - Radionuclide transport calculations
Energy Technology Data Exchange (ETDEWEB)
Lindgren, Maria [Kemakta Konsult AB, Stockholm (Sweden); Lindstroem, Fredrik [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)
1999-12-01
An essential component of a safety assessment is to calculate radionuclide release and dose consequences for different scenarios and cases. The SKB tools for such a quantitative assessment are used to calculate the maximum releases and doses for the hypothetical repository sites Aberg, Beberg and Ceberg for the initial canister defect scenario and also for the glacial melting case for Aberg. The reasonable cases, i.e. all parameters take reasonable values, results in maximum biosphere doses of 5x10{sup -8} Sv/yr for Aberg, 3x10{sup -8} Sv/yr for Beberg and 1x10{sup -8} Sv/yr for Ceberg for peat area. These doses lie significantly below 0.15 mSv/yr. (A dose of 0.15 mSv/yr for unit probability corresponds to the risk limit of 10{sup -5} per year for the most exposed individuals recommended in regulations.) The conclusion that the maximum risk would lie well below 10{sup -5} per year is also demonstrated by results from the probabilistic calculations, which directly assess the resulting risk by combining dose and probability estimates. The analyses indicate that the risk is 2x10{sup -5} Sv/yr for Aberg, 8x10{sup -7} Sv/yr for Beberg and 3x10{sup -8} Sv/yr for Ceberg. The analysis shows that the most important parameters in the near field are the number of defective canisters and the instant release fraction. The influence from varying one parameter never changes the doses as much as an order of magnitude. In the far field the most important uncertainties affecting release and retention are associated with permeability and connectivity of the fractures in the rock. These properties affect several parameters. Highly permeable and well connected fractures imply high groundwater fluxes and short groundwater travel times. Sparsely connected or highly variable fracture properties implies low flow wetted surface along migration paths. It should, however, be remembered that the far-field parameters have little importance if the near-field parameters take their reasonable
SR 97 - Radionuclide transport calculations
International Nuclear Information System (INIS)
Lindgren, Maria; Lindstroem, Fredrik
1999-12-01
An essential component of a safety assessment is to calculate radionuclide release and dose consequences for different scenarios and cases. The SKB tools for such a quantitative assessment are used to calculate the maximum releases and doses for the hypothetical repository sites Aberg, Beberg and Ceberg for the initial canister defect scenario and also for the glacial melting case for Aberg. The reasonable cases, i.e. all parameters take reasonable values, results in maximum biosphere doses of 5x10 -8 Sv/yr for Aberg, 3x10 -8 Sv/yr for Beberg and 1x10 -8 Sv/yr for Ceberg for peat area. These doses lie significantly below 0.15 mSv/yr. (A dose of 0.15 mSv/yr for unit probability corresponds to the risk limit of 10 -5 per year for the most exposed individuals recommended in regulations.) The conclusion that the maximum risk would lie well below 10 -5 per year is also demonstrated by results from the probabilistic calculations, which directly assess the resulting risk by combining dose and probability estimates. The analyses indicate that the risk is 2x10 -5 Sv/yr for Aberg, 8x10 -7 Sv/yr for Beberg and 3x10 -8 Sv/yr for Ceberg. The analysis shows that the most important parameters in the near field are the number of defective canisters and the instant release fraction. The influence from varying one parameter never changes the doses as much as an order of magnitude. In the far field the most important uncertainties affecting release and retention are associated with permeability and connectivity of the fractures in the rock. These properties affect several parameters. Highly permeable and well connected fractures imply high groundwater fluxes and short groundwater travel times. Sparsely connected or highly variable fracture properties implies low flow wetted surface along migration paths. It should, however, be remembered that the far-field parameters have little importance if the near-field parameters take their reasonable values. In that case almost all
Energy Technology Data Exchange (ETDEWEB)
Masrour, R., E-mail: rachidmasrour@hotmail.com [Laboratory of Materials, Processes, Environment and Quality, Cady Ayyed University, National School of Applied Sciences, 63 46000, Safi (Morocco); LMPHE (URAC 12), Faculty of Science, Mohammed V-Agdal University, Rabat (Morocco); Hlil, E.K. [Institut Néel, CNRS et Université Joseph Fourier, BP 166, F-38042 Grenoble Cedex 9 (France); Hamedoun, M. [Institute of Nanomaterials and Nanotechnologies, MAScIR, Rabat (Morocco); Benyoussef, A. [LMPHE (URAC 12), Faculty of Science, Mohammed V-Agdal University, Rabat (Morocco); Institute of Nanomaterials and Nanotechnologies, MAScIR, Rabat (Morocco); Hassan II Academy of Science and Technology, Rabat (Morocco); Boutahar, A.; Lassri, H. [LPMMAT, Université Hassan II-Casablanca, Faculté des Sciences, BP 5366 Maârif (Morocco)
2015-11-01
The self-consistent ab initio calculations, based on DFT (Density Functional Theory) approach and using FLAPW (Full potential Linear Augmented Plane Wave) method, are performed to investigate both electronic and magnetic properties of the Mn{sub 2}Au. Polarized spin and spin–orbit coupling are included in calculations within the framework of the antiferromagnetic state between two adjacent Mn plans. Magnetic moment considered to lie along (110) axes are computed. Obtained data from ab initio calculations are used as input for the high temperature series expansions (HTSEs) calculations to compute other magnetic parameters. The exchange interactions between the magnetic atoms Mn–Mn in Mn{sub 2}Au are given by using the experiment results and the mean field theory. The High Temperature Series Expansions (HTSEs) of the magnetic susceptibility with the magnetic moments in Mn{sub 2}Au (m{sub Mn}) is given up to tenth order series in, 1/k{sub B}T. The Néel temperature T{sub N} is obtained by HTSEs combined with the Padé approximant method. The critical exponent associated with the magnetic susceptibility is deduced as well. - Highlights: • The both electronic and magnetic properties of the Mn{sub 2}Au are studied. • The exchange interactions between the magnetic atoms Mn–Mn in Mn{sub 2}Au are given. • The Néel temperature T{sub N} of Mn{sub 2}Au is obtained by HTSEs method. • The critical exponent associated with the magnetic susceptibility is deduced.
Methodologies of Uncertainty Propagation Calculation
International Nuclear Information System (INIS)
Chojnacki, Eric
2002-01-01
After recalling the theoretical principle and the practical difficulties of the methodologies of uncertainty propagation calculation, the author discussed how to propagate input uncertainties. He said there were two kinds of input uncertainty: - variability: uncertainty due to heterogeneity, - lack of knowledge: uncertainty due to ignorance. It was therefore necessary to use two different propagation methods. He demonstrated this in a simple example which he generalised, treating the variability uncertainty by the probability theory and the lack of knowledge uncertainty by the fuzzy theory. He cautioned, however, against the systematic use of probability theory which may lead to unjustifiable and illegitimate precise answers. Mr Chojnacki's conclusions were that the importance of distinguishing variability and lack of knowledge increased as the problem was getting more and more complex in terms of number of parameters or time steps, and that it was necessary to develop uncertainty propagation methodologies combining probability theory and fuzzy theory
Thermodynamic Calculations for Systems Biocatalysis
DEFF Research Database (Denmark)
Abu, Rohana; Gundersen, Maria T.; Woodley, John M.
2015-01-01
the transamination of a pro-chiral ketone into a chiral amine (interesting in many pharmaceutical applications). Here, the products are often less energetically stable than the reactants, meaning that the reaction may be thermodynamically unfavourable. As in nature, such thermodynamically-challenged reactions can...... on the basis of kinetics. However, many of the most interesting non-natural chemical reactions which could potentially be catalysed by enzymes, are thermodynamically unfavourable and are thus limited by the equilibrium position of the reaction. A good example is the enzyme ω-transaminase, which catalyses...... be altered by coupling with other reactions. For instance, in the case of ω-transaminase, such a coupling could be with alanine dehydrogenase. Herein, the aim of this work is to identify thermodynamic bottlenecks within a multi-enzyme process, using group contribution method to calculate the Gibbs free...
Calculating utility prudency issue costs
International Nuclear Information System (INIS)
Nielsen, K.R.
1985-01-01
The nuclear industry, particularly utilities and their construction, engineering and vendor agents, is faced with a surging increase in prudency management audits. What started as primarily a nuclear project-oriented requirement has spread to encompass most significant utility capital construction projects. Such audits are often a precedent condition to commencement of rate hearings. The cost engineer, a primary major capital construction project participant, is required to develop or critique ''prudency issue'' costs as part of such audits. Although utility costs in the broadest sense are potentially at issue, this paper concentrates on the typical project/construction management costs. The costs of design, procurement and construction are all subject to the calculation process
Shielding calculations. Optimization vs. Paradigms
International Nuclear Information System (INIS)
Cornejo Diaz, Nestor; Hernandez Saiz, Alejandro; Martinez Gonzalez, Alina
2005-01-01
Many radiation shielding barriers in Cuba have been designed according to the criterion of Maxi-mum Projected Dose Rates. This fact has created the paradigm of low dose rates. Because of this, dose rate levels greater than units of Sv.h-1 would be considered unacceptable by many specialists, regardless of the real exposure times. Nowadays many shielding barriers are being designed using dose constraints in real exposure times. Behind the new barriers, dose rates could be notably greater than those behind the traditional ones, and it does not imply inadequate designs or constructive errors. In this work were obtained significant differences in dose rate levels and shield-ing thicknesses calculated by both methods for some typical installations. The work concludes that real exposure time approach is more adequate in order to optimise Radiation Protection, although this method should be carefully applied
Dyscalculia and the Calculating Brain.
Rapin, Isabelle
2016-08-01
Dyscalculia, like dyslexia, affects some 5% of school-age children but has received much less investigative attention. In two thirds of affected children, dyscalculia is associated with another developmental disorder like dyslexia, attention-deficit disorder, anxiety disorder, visual and spatial disorder, or cultural deprivation. Infants, primates, some birds, and other animals are born with the innate ability, called subitizing, to tell at a glance whether small sets of scattered dots or other items differ by one or more item. This nonverbal approximate number system extends mostly to single digit sets as visual discrimination drops logarithmically to "many" with increasing numerosity (size effect) and crowding (distance effect). Preschoolers need several years and specific teaching to learn verbal names and visual symbols for numbers and school agers to understand their cardinality and ordinality and the invariance of their sequence (arithmetic number line) that enables calculation. This arithmetic linear line differs drastically from the nonlinear approximate number system mental number line that parallels the individual number-tuned neurons in the intraparietal sulcus in monkeys and overlying scalp distribution of discrete functional magnetic resonance imaging activations by number tasks in man. Calculation is a complex skill that activates both visual and spatial and visual and verbal networks. It is less strongly left lateralized than language, with approximate number system activation somewhat more right sided and exact number and arithmetic activation more left sided. Maturation and increasing number skill decrease associated widespread non-numerical brain activations that persist in some individuals with dyscalculia, which has no single, universal neurological cause or underlying mechanism in all affected individuals. Copyright © 2016 Elsevier Inc. All rights reserved.
Prediction of fission mass-yield distributions based on cross section calculations
International Nuclear Information System (INIS)
Hambsch, F.-J.; G.Vladuca; Tudora, Anabella; Oberstedt, S.; Ruskov, I.
2005-01-01
For the first time, fission mass-yield distributions have been predicted based on an extended statistical model for fission cross section calculations. In this model, the concept of the multi-modality of the fission process has been incorporated. The three most dominant fission modes, the two asymmetric standard I (S1) and standard II (S2) modes and the symmetric superlong (SL) mode are taken into account. De-convoluted fission cross sections for S1, S2 and SL modes for 235,238 U(n, f) and 237 Np(n, f), based on experimental branching ratios, were calculated for the first time in the incident neutron energy range from 0.01 to 5.5 MeV providing good agreement with the experimental fission cross section data. The branching ratios obtained from the modal fission cross section calculations have been used to deduce the corresponding fission yield distributions, including mean values also for incident neutron energies hitherto not accessible to experiment
Search for weak M 1 transitions in 48Ca with inelastic proton scattering
Mathy, M.; Birkhan, J.; Matsubara, H.; von Neumann-Cosel, P.; Pietralla, N.; Ponomarev, V. Yu.; Richter, A.; Tamii, A.
2017-05-01
Background: The quenching of spin-isospin modes in nuclei is an important field of research in nuclear structure. It has an impact on astrophysical reaction rates and on fundamental processes like neutrinoless double-β decay. Gamow-Teller (GT) and spin-flip M 1 strengths are quenched. Concerning the latter, the Jπ=1+ resonance in the doubly magic nucleus 48Ca, dominated by a single transition, serves as a reference case. Purpose: The aim of the present work is to search for weak M 1 transitions in 48Ca with a high-resolution (p ,p') experiment at 295 MeV and forward angles including 0∘ and a comparison with results from a similar study using backward-angle electron scattering at low momentum transfers in order to estimate their contribution to the total B (M 1 ) strength in 48Ca. Methods: The spin-M 1 cross sections of individual peaks in the spectra are deduced with a multipole decomposition analysis (MDA) and converted to reduced spin-M 1 transition strengths by using the unit cross-section method. For a comparison with electron-scattering results, corresponding reduced B (M 1 ) transition strengths are extracted following the approach outlined in Birkhan et al. [Phys. Rev. C 93, 041302(R) (2016), 10.1103/PhysRevC.93.041302]. Results: In total, 30 peaks containing a M 1 contribution are found in the excitation energy region 7-13 MeV. The resulting B (M 1 ) strength distribution compares well to the electron-scattering results considering different factors limiting the sensitivity in both experiments and the enhanced importance of mechanisms breaking the proportionality of nuclear cross sections and electromagnetic matrix elements for weak transitions as studied here. The total strength of 1.14(7) μN2 deduced assuming a nonquenched isoscalar part of the (p ,p') cross sections agrees with the (e ,e') result of 1.21(13) μN2. A bin-wise analysis above 10 MeV provides an upper limit of 1.51(17) μN2. Conclusions: The present results confirm the previous electron
Atmospheric phenomena deduced from radiosonde and GPS ...
Indian Academy of Sciences (India)
gation and atmospheric modeling studies. ... the earth. Atmosphere causes refraction of radio signals as it passes through it. This time ... from cloud, aerosol, precipitation and it provides ... in the troposphere have strong influence on tropical.
Atmospheric phenomena deduced from radiosonde and GPS ...
Indian Academy of Sciences (India)
The tropopause height and tropopause temperature are sensitive to temperature changes in troposphere and stratosphere. These are the measures of global climatic variability. Atmospheric profiles of temperature, refractivity and water vapour are always needed for communication, navigation and atmospheric modeling ...
Deducing the reachable space from fingertip positions.
Hai-Trieu Pham; Pathirana, Pubudu N
2015-01-01
The reachable space of the hand has received significant interests in the past from relevant medical researchers and health professionals. The reachable space was often computed from the joint angles acquired from a motion capture system such as gloves or markers attached to each bone of the finger. However, the contact between the hand and device can cause difficulties particularly for hand with injuries, burns or experiencing certain dermatological conditions. This paper introduces an approach to find the reachable space of the hand in a non-contact measurement form utilizing the Leap Motion Controller. The approach is based on the analysis of each position in the motion path of the fingertip acquired by the Leap Motion Controller. For each position of the fingertip, the inverse kinematic problem was solved under the physiological multiple constraints of the human hand to find a set of all possible configurations of three finger joints. Subsequently, all the sets are unified to form a set of all possible configurations specific for that motion. Finally, a reachable space is computed from the configuration corresponding to the complete extension and the complete flexion of the finger joint angles in this set.
Calculation of nuclear radius using alpha decay
International Nuclear Information System (INIS)
Castro, R.B. de.
1988-01-01
Using a Quantum Theory approach for the Alpha-Decay process, a formula is deduced for determination of the nuclear radius of the s-state, that is, a nuclear model with a spherical shell. The hypothesis that it is possible to individualize the alpha particle and the daughter nucleus at the moment of the alpha particle emission is considered. In considered in these conditions, the treatment of a two body problem considered as point particles, repelling each other by Coulomb's Law. Using the new values of the fundamental physical constants, experimentally determinated, by substitution of their numerical values in the proposed, new values of nuclear radii are obtained. These values are compared with those found in the literature. (author) [pt
International Nuclear Information System (INIS)
Trkov, A.; Budnar, M.; Copic, M.; Perdan, A.; Ravnik, M.
1982-01-01
Multigroup constants for 1-H-1, 92-U-235, and 92-U-238 have been calculated. Averaged cross-sections and other constants have been prepared in the WIMS 69-group format. Comparison has been made between group constants obtained with several evaluated libraries (KEDAK-3 1975, 1979, ENDF/B-4, ENDF/B-5) and the WIMS-D library. Observed differences are most pronounced in the resonance and fast region. From test runs on fuel cell with the WIMS program it can be deduced that these differences affect the fewgroup constants significantly. (author)
Stability calculations for MHD magnets
International Nuclear Information System (INIS)
Turner, L.R.; Wang, S.T.; Harrang, J.
1978-01-01
When a cryostable composite conductor carrying current experiences a heat input from a mechanical perturbation, a normal region develops which initially propagates and then either collapses or continues to propagate. A computer model has been devised to study this phenomenon. The model incorporates initial or continuing heat input from mechanical perturbations, heat conducted to the neighboring elements of the conductor and, if appropriate, heat conducted through insulation to neighboring turns. Heat is transferred to the helium coolant according to a specified heat transfer coefficient. If the element of conductor is in a normal or current-sharing state, resistive heating also occurs. The (unstable) equilibrium state of heat generation and conduction has been studied; results agree with those of a static calculation. The model has been validated against experimental measurements of response to heat pulses. The model suffers from uncertainties in transient heat transfer to the helium, but even more from uncertainties in the perturbing heat pulse which the magnet might be expected to suffer
Selfconsistent calculations for hyperdeformed nuclei
Energy Technology Data Exchange (ETDEWEB)
Molique, H.; Dobaczewski, J.; Dudek, J.; Luo, W.D. [Universite Louis Pasteur, Strasbourg (France)
1996-12-31
Properties of the hyperdeformed nuclei in the A {approximately} 170 mass range are re-examined using the self-consistent Hartree-Fock method with the SOP parametrization. A comparison with the previous predictions that were based on a non-selfconsistent approach is made. The existence of the {open_quotes}hyper-deformed shell closures{close_quotes} at the proton and neutron numbers Z=70 and N=100 and their very weak dependence on the rotational frequency is suggested; the corresponding single-particle energy gaps are predicted to play a role similar to that of the Z=66 and N=86 gaps in the super-deformed nuclei of the A {approximately} 150 mass range. Selfconsistent calculations suggest also that the A {approximately} 170 hyperdeformed structures have neglegible mass asymmetry in their shapes. Very importantly for the experimental studies, both the fission barriers and the {open_quotes}inner{close_quotes} barriers (that separate the hyperdeformed structures from those with smaller deformations) are predicted to be relatively high, up to the factor of {approximately}2 higher than the corresponding ones in the {sup 152}Dy superdeformed nucleus used as a reference.
Calculating system reliability with SRFYDO
Energy Technology Data Exchange (ETDEWEB)
Morzinski, Jerome [Los Alamos National Laboratory; Anderson - Cook, Christine M [Los Alamos National Laboratory; Klamann, Richard M [Los Alamos National Laboratory
2010-01-01
SRFYDO is a process for estimating reliability of complex systems. Using information from all applicable sources, including full-system (flight) data, component test data, and expert (engineering) judgment, SRFYDO produces reliability estimates and predictions. It is appropriate for series systems with possibly several versions of the system which share some common components. It models reliability as a function of age and up to 2 other lifecycle (usage) covariates. Initial output from its Exploratory Data Analysis mode consists of plots and numerical summaries so that the user can check data entry and model assumptions, and help determine a final form for the system model. The System Reliability mode runs a complete reliability calculation using Bayesian methodology. This mode produces results that estimate reliability at the component, sub-system, and system level. The results include estimates of uncertainty, and can predict reliability at some not-too-distant time in the future. This paper presents an overview of the underlying statistical model for the analysis, discusses model assumptions, and demonstrates usage of SRFYDO.
The (n,p) reaction as a probe of nuclear structure
International Nuclear Information System (INIS)
Jackson, K.P.; Celler, A.
1988-08-01
An account is given of some results of studies of the (n,p) reaction on nuclear targets at TRIUMF. The (n,p) reaction, inducing spin flip transitions in isospin space, appears to exhibit a unique sensitivity to certain aspects of nuclear structure. The TRIUMF facility is the first to exploit the (n,p) reaction as a detailed probe of nuclear structure at energies above 65 MeV. In the (n,p) reaction Fermi transitions are absent, but there is a dramatic impact on Gamow-Teller and other collective transactions. Some nuclear transition matrix elements can be estimated on the basis of (n,p) measurements. Experiments have been carried out at TRIUMF on Li 6 , Fe 5 4, and Zr 9 0 targets. The calibration of the (n,p) reaction as a probe of the Gamow-Teller strength B + GT has been achieved for three targets. (L.L.) (45 refs., 10 figs.)
Koettgen, Julius; Schmidt, Peter C.; Bučko, Tomáš; Martin, Manfred
2018-01-01
We have studied the free energy migration barriers Δ F‡ for oxygen diffusion in pure ceria and Sm-doped ceria for the temperatures 300, 700, and 1000 K. We used the density functional theory in the generalized gradient approximation and an additional Hubbard U parameter for the Ce 4 f electronic states. We compare the results for the free energy deduced from three different methods. First, a static harmonic approach is applied in which the temperature dependent vibrational contributions to energy and entropy are deduced from the phonon frequencies of supercells with a fixed volume. Second, a static quasiharmonic approach is used in which a part of the anharmonicity effect is introduced via an implicit dependence of the harmonic frequencies on the thermally expanding cell volume. Third, the free energy barriers are calculated using metadynamics and molecular dynamics in which anharmonicity effects are naturally taken into account. The three methods examined in this study lead to distinctly different results. According to the harmonic approximation, the migration free energy difference Δ F‡ increases with increasing temperature due to an increasing entropic contribution. According to the quasiharmonic approximation, the migration free energy is independent of temperature. Finally, molecular dynamics predicts a thermally induced increase in the migration free energy. We conclude that temperature dependent experimental lattice constants cancel out the increasing entropic contribution with increasing temperature in the static quasiharmonic approach. The full consideration of anharmonicity effects in the metadynamics method again leads to a temperature dependent migration free energy.
International Nuclear Information System (INIS)
Kuznetsov, Yu.K.; Pinos, I.B.; Tyupa, V.I.
1999-01-01
With formulas for averaging over magnetic surfaces general analytical expressions are here deduced to determine the rotational transform angles in stellarator systems having different plasma pressure profiles
Software testing in roughness calculation
International Nuclear Information System (INIS)
Chen, Y L; Hsieh, P F; Fu, W E
2005-01-01
A test method to determine the function quality provided by the software for roughness measurement is presented in this study. The function quality of the software requirements should be part of and assessed through the entire life cycle of the software package. The specific function, or output accuracy, is crucial for the analysis of the experimental data. For scientific applications, however, commercial software is usually embedded with specific instrument, which is used for measurement or analysis during the manufacture process. In general, the error ratio caused by the software would be more apparent especially when dealing with relatively small quantities, like the measurements in the nanometer-scale range. The model of 'using a data generator' proposed by NPL of UK was applied in this study. An example of the roughness software is tested and analyzed by the above mentioned process. After selecting the 'reference results', the 'reference data' was generated by a programmable 'data generator'. The filter function of 0.8 mm long cutoff value, defined in ISO 11562 was tested with 66 sinusoid data at different wavelengths. Test results from commercial software and CMS written program were compared to the theoretical data calculated from ISO standards. As for the filter function in this software, the result showed a significant disagreement between the reference and test results. The short cutoff feature for filtering at the high frequencies does not function properly, while the long cutoff feature has the maximum difference in the filtering ratio, which is more than 70% between the wavelength of 300 μm and 500 μm. Conclusively, the commercial software needs to be tested more extensively for specific application by appropriate design of reference dataset to ensure its function quality
Nonlinear calculations for bump Cepheids
International Nuclear Information System (INIS)
Hodson, S.W.; Cox, A.N.
1979-01-01
Hydrodynamic calculations to find strictly periodic solutions for the fundamental mode pulsations of 7 M/sub sun/ models were made using the von Sengbusch--Stellingwerf relaxation method. The models have a helium enrichment in the surface convection zones to Y = 0.78, which from the linear theory period ratio π 2 /π 0 and the Simon and Schmidt resonance hypothesis, should give the observed Hertzsprung progression of light and velocity curve bump phase with period. These surface helium enhanced models show the proper nonlinear bump phase behavior without resort to any mass loss before or during the blue loop phases of yellow giant evolution. At 6000 K and the evolution theory luminosity of 4744 L/sub sun/ for 7 M/sub sun/, that is, at a fundamental mode period of 8.5 day, the velocity curve bump is well after the maximum expansion velocity. At 5400 K and at the same luminosity (period of 12.5 days), there is a bump on the velocity curve well before maximum expansion velocity time. The latter case seems to exhibit the Christy echos but not the former. The echo interpretation may not be appropriate for these masses which are larger than the anomalous masses used by Christy, Stobie, and Adams. Resonance of the fundamental and second overtone modes should not necessarily show echos of surface disturbances from the center. The conclusion is that helium enrichment in the surface convection zones can adequately explain observations of bump Cepheids at evolution theory masses. 12 references
The effect of rock electrical parameters on the calculation of reservoir saturation
International Nuclear Information System (INIS)
Li, Xiongyan; Qin, Ruibao; Liu, Chuncheng; Mao, Zhiqiang
2013-01-01
The error in calculating a reservoir saturation caused by the error in the cementation exponent, m, and the saturation exponent, n, should be analysed. In addition, the influence of m and n on the reservoir saturation should be discussed. Based on the Archie formula, the effect of variables m and n on the reservoir saturation is analysed, while the formula for the error in calculating the reservoir saturation, caused by the error in m and n, is deduced, and the main factors affecting the error in reservoir saturation are illustrated. According to the physical meaning of m and n, it can be interpreted that they are two independent parameters, i.e., there is no connection between m and n. When m and n have the same error, the impact of the variables on the calculation of the reservoir saturation should be compared. Therefore, when the errors of m and n are respectively equal to 0.2, 0.4 and 0.6, the distribution range of the errors in calculating the reservoir saturation is analysed. However, in most cases, the error of m and n is about 0.2. When the error of m is 0.2, the error in calculating the reservoir saturation ranges from 0% to 35%. Meanwhile, when the error in n is 0.2, the error in calculating the reservoir saturation is almost always below 5%. On the basis of loose sandstone, medium sandstone, tight sandstone, conglomerate, tuff, breccia, basalt, andesite, dacite and rhyolite, this paper first analyses the distribution range and change amplitude of m and n. Second, the impact of m and n on the calculation of reservoir saturation is elaborated upon. With regard to each lithology, the distribution range and change amplitude of m are greater than those of n. Therefore, compared with n, the effect of m on the reservoir saturation is stronger. The influence of m and n on the reservoir saturation is determined, and the error in calculating the reservoir saturation caused by the error of m and n is calculated. This is theoretically and practically significant for
Quark-spin isospin sum rules and the Adler-Weisberger relation in nuclei
International Nuclear Information System (INIS)
Delorme, J.; Ericson, M.
1982-01-01
We use a quark model to extend the classical Gamow-Teller sum rule for the difference of the β - and β + strengths to excitations of the nucleon (mainly the Δ isobar). A schematic model illustrates the realization of the new sum rule when a particle-hole force is introduced. We discuss the connection of our result with the model-independent Adler-Weisberger sum rule. (orig.)
International Nuclear Information System (INIS)
Horowitz, C.J.; Macfarlane, M.H.; Serot, B.D.
1989-01-01
In this period covered by this report (April 1, 1988 to March 31, 1989), work focused on six main areas: Relativistic Theories of Nuclear Structure and Saturation; Relativistic Descriptions of Proton- Nucleus and Electron-Nucleus Scattering; Nonrelativistic Theory of Nucleon-Nucleus Reactions; Gamow-Teller Excitations in Nuclear Charge- Exchange Reactions; Relativistic Many-Body Theory at Finite Temperature and Density and Relativistic Atomic Physics of High Z Atoms. Results and publications in these areas are summarized in this report
International Nuclear Information System (INIS)
Horowitz, C.J.; Macfarlane, M.H.; Serot, B.D.
1988-01-01
In the period covered by this report (April 1, 1987 to March 31, 1988), work focused on five main areas: Relativistic Theories of Nuclear Structure and Saturation; Relativistic Descriptions of Proton-Nucleus Scattering; Multipole Sum Rules and Ground-State Correlations; Gamow-Teller Excitations in Nuclear Charge-Exchange Reactions; Relativistic Many-Body Theory at Finite Temperature and Density. Results and publications in these areas are summarized in this report. 32 refs., 1 fig
Charge exchange reactions and solar neutrino detection in 81Br
International Nuclear Information System (INIS)
Liu, K.F.; Gabbard, F.
1983-01-01
The feasibility of 81 Br as the detector of the solar neutrino flux hinges upon the knowledge of the Gamow-Teller matrix element from the ground state of 81 Br to the (5/2) - state at 0.457 MeV in 81 Kr. The possibility of obtaining this matrix element is discussed in terms of the (p,n) and ( 3 He, t) charge exchange reactions. .ID CR2009 .PG 98 112
Measurement of Angular Correlations in the Decay of Polarized Neutrons
DEFF Research Database (Denmark)
Christensen, Carl Jørgen; Krohn, V.E.; Ringo, G.R.
1970-01-01
The electron-momentum-neutron-spin correlation coefficient was found to be A=-0.115±0.008, and the antineutrino-momentum-neutron-spin correlation coefficient was found to be B=1.00±0.05. The value of A leads to |GA/GV|=1.26±0.02 for the ratio of Gamow-Teller-to-Fermi coupling constants in β decay...
International Nuclear Information System (INIS)
Armour, E.A.G.; Plummer, M.
1989-01-01
An explanation is given of why it is necessary to include long-range polarisation functions in the trial function when carrying out Kohn calculations of low-energy positron (and electron) scattering by atoms and simple molecules. The asymptotic form of these functions in low-energy e + -H 2 scattering is deduced. Appropriate functions with this asymptotic form are used to represent the closed-channel part of the wavefunction in a Kohn calculation of the lowest partial wave of Σ u + symmetry in e + -H 2 scattering at very low energies. For k≤0.03a 0 -1 , the results obtained are in good agreement with those obtained using the Born approximation and the asymptotic forms of the static and polarisation potentials. The relationship is pointed out between this method of taking into account long-range polarisation and the polarised pseudostate method used in R-matrix calculations. (author)