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Sample records for 46ti 64zn 114sn

  1. The consistency of the data for neutron fission averaged cross-sections of threshold reactions: A study on the cross-section of 46Ti(n,p)46Sc, 47Ti(n,p)47Sc, 48Ti(n,p)48Sc and 64Zn(n,p)64Cu reactions

    The consistency of the published values for fission averaged cross-sections of threshold reactions induced in a nuclear reactor is analyzed. The influence of the literature data involved in the determination of these cross-sections is discussed. Renormalizations based on cross-sections value for the standard reactions, isotopic abundances of the precursors and radiation emission probabilities of the radionuclide under study and the monitor, are applied to the evaluation of the cross-sections for the reactions: 46Ti(n,p)46Sc; 47Ti(n,p)47Sc; 48Ti(n,p)48Sc; and 64Zn(n,p)64Cu. - Highlights: • Some published data on cross-sections averaged over a fission spectrum are analyzed. • The reactions were 46Ti(n,p)46Sc; 47Ti(n,p)47Sc; 48Ti(n,p)48Sc and 64Zn(n,p)64Cu. • Renormalization as a function of five critical parameters was performed. • Averages of the renormalized values were calculated and the results discussed

  2. Evaluation of Excitation Function for 64Zn

    2008-01-01

    <正>Present work concerns the evaluated neutron induced excitation function data for 64Zn, and mainly on (n, γ) reaction channel. The related experimental data were collected, analyzed and corrected for 64Zn

  3. Elastic and inelastic {alpha}-scattering cross-sections obtained with the 44 MeV fixed energy Saclay cyclotron on separated targets of {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 40}Ca, {sup 46}Ti, {sup 48}Ti, {sup 50}Ti, {sup 52}Cr, {sup 54}Fe, {sup 56}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 112}Sn, {sup 114}Sn, {sup 116}Sn, {sup 118}Sn, {sup 120}Sn, {sup 122}Sn, {sup 124}Sn and {sup 208}Pb using the Saclay fixed-energy cyclotron; Sections efficaces differentielles elastiques et inelastiques obtenues par diffusion de particules {alpha} de 44 MeV sur des cibles de {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 40}Ca, {sup 46}Ti, {sup 48}Ti, {sup 50}Ti, {sup 52}Cr, {sup 54}Fe, {sup 56}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 112}Sn, {sup 114}Sn, {sup 116}Sn, {sup 118}Sn, {sup 120}Sn, {sup 122}Sn, {sup 124}Sn et {sup 208}Pb au cyclotron a energie fixe de saclay

    Bruge, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement de physique nucleaire, service de physique nucleaire a moyenne energie

    1967-01-01

    This report contains elastic and inelastic {alpha}-scattering cross-sections obtained with the 44 MeV fixed energy Saclay cyclotron on Mg, Ca, Ti, Cr, Fe, Ni, Co, Zn, Sn and Pb enriched targets. (author) [French] Ce rapport contient les tableaux des sections efficaces differentielles obtenues par diffusion elastique et inelastique des particules {alpha} de 44 MeV, fournies par le cyclotron a energie fixe de Saclay, sur des cibles d'isotopes separes de Mg, Ca, Ti, Cr, Fe, Ni, Co, Zn, Sn et Pb. (auteur)

  4. Comparison between the exact and the thermal description of the pairing interaction in 114Sn

    The pairing interaction is solved exactly in the 114Sn nucleus using a realistic strength parameter as well as standard energy levels for the shell seniority zero states. The same single-particle and two-body Hamiltonian is treated with finite-temperature BCS and the thermal random-phase approximation. The results obtained through these calculations are compared to obtain insight about the suitability of the thermal approach to the description of nuclear phenomena

  5. Enhanced $0_{g.s.}^+ \\to 2_1^+$ E2 Transition Strength in $^{112,114}$Sn

    Kumar, R; Jhingan, A; Muralithar, S; Mukherjee, S; Reiter, P; Gorska, M; Bhowmik, R K; Cederkall, J; Siwal, D; Doornenbal, P; Garg, R; Appannababu, S; Kojouharov, I; Grawe, H; Singh, P P; Mandal, S; Sharma, A; Schaffner, H; Ekstrom, A; Caceres, L; Prokopowicz, W; Kaur, J; Gerl, J; Singh, R P; Bednarczyk, P

    2011-01-01

    The poorly known B(E2; 0(+) -> 2(+)) values of (112)Sn and (114)Sn have been measured to high precision. Two Coulomb excitation experiments were performed to determine the reduced transition probabilities relative to (116)Sn in order to minimize the systematic errors. The obtained B(E2 up arrow) values of 0.242(8) e(2)b(2) for (112)Sn and 0.232(8) e(2)b(2) for (114)Sn confirm the tendency of large B(E2 up arrow) values for the lighter tin isotopes below the midshell (116)Sn that has been observed recently in various radioactive ion beam experiments.

  6. Experimental study of the collision 11Be + 64Zn around the Coulomb barrier

    Di Pietro, A.; Scuderi, V.; Moro, A. M.; Acosta Sánchez, Luis Armando; Amorini, F.; Borge, M. J. G.; Gómez Camacho, Joaquín; Jeppesen, H.; Lattuada, M.; Martel Bravo, Ismael; Milin, M.; Musumarra, A.; Papa, M.; Pellegriti, M. G.; Pérez Bernal, Francisco

    2012-01-01

    In this paper details of the experimental procedure and data analysis of the collision of 11Be +64Zn around the Coulomb barrier are described and discussed in the framework of different theoretical approaches. In a previous work, the elastic scattering angular distribution of the collisions 9 ,10Be +64Zn as well as the angular distribution for the quasielastic scattering and transfer/breakup cross sections for the 11Be +64Zn reaction were briefly reported. The suppression of the quasielastic ...

  7. Effects of nuclear breakup channel on fusion of 6Li+64Zn system around barrier energies

    We have studied the effects of breakup, occurring due to the nuclear interaction between weakly bound 6Li and tightly bound 64Zn isotopes, on the fusion reaction at near barrier energies within the framework of dynamic polarization potential (DPP) approach. When the nuclear induced dynamic polarization potential is taken into account sub barrier enhancement and above barrier suppression have been found which improves the matching between the fusion excitation function data and predictions for 6Li+64Zn system significantly. (author)

  8. Thermal quantities of {sup 46}Ti

    Rahmatinejad, A. [Department of Physics, Faculty of Science, University of Zanjan, Zanjan (Iran, Islamic Republic of); Razavi, R., E-mail: rrazavin@ihu.ac.ir [Physics Department, Faculty of Science, Imam Hossein Comprehensive University, Tehran (Iran, Islamic Republic of); Kakavand, T. [Department of Physics, Faculty of Science, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of)

    2015-07-15

    Thermodynamic quantities of {sup 46}Ti have been calculated in the framework of the BCS model with inclusion of modified nuclear pairing gap (MPBCS) that was proposed in our previous publication. Using modified paring gap results in an S-shaped heat capacity curve at critical temperature with a smooth behavior instead of singular behavior of the same curve in the BCS calculations. In addition the thermal quantities have been extracted within the framework of a canonical ensemble according to the new experimental data on nuclear level densities measured by the Oslo group. Comparison shows a good agreement between our calculations in MPBCS and the extracted quantities in the canonical ensemble framework.

  9. Deformed shell model studies of spectroscopic properties of 64Zn and 64Ni and the positron double beta decay of 64Zn

    R Sahu; V K B Kota

    2014-04-01

    The spectroscopic properties of 64Zn and 64Ni are calculated within the framework of the deformed shell model (DSM) based on Hartree–Fock states. GXPF1A interaction in 1 $f_{7/2}$, 2$p_{3/2}$, 1$f_{5/2}$ and 2$p_{1/2}$ space with 40Ca as the core is employed. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these two nuclei considered, nuclear transition matrix elements (NTME) for the neutrinoless positron double beta decay (0 + and 0 +EC) of 64Zn are calculated. The two-neutrino positron double beta decay halflife is also calculated for this nucleus.

  10. Double folding model analysis of elastic scattering of halo nucleus 11Be from 64Zn

    M Hemalatha

    2014-05-01

    Calculations of elastic scattering cross-sections for 9,10,11Be+64Zn at near-Coulomb barrier energy have been performed using a potential obtained from the double folding model and are compared with the experiment. In the framework of the double folding model, the nuclear matter densities of 9,10,11Be projectiles and a 64Zn target are folded with the complex energydependent effective M3Y interaction. The angular distributions of the differential cross-section for 9,10Be scattering from 64Zn at $E_{c.m.} ≈$24.5 MeV agree remarkably well with the data, while in case of 11Be, calculations show a Coulomb–nuclear interference peak which is not observed in the data.

  11. Elastic scattering and fusion studies in the reactions $^{10,11}$Be + $^{64}$Zn

    2002-01-01

    We propose to measure elastic scattering and fusion excitation functions for the reactions $^{10,11}$Be + $^{64}$Zn at 3.1 MeV/u . The aim of the experiment is to investigate possible effects of the halo structure of the $^{11}$Be nucleus on the reaction mechanisms at energy around the Coulomb barrier. For this purpose a comparison with the reaction induced by the $^{10}$Be nucleus is required.

  12. Elastic and inelastic scattering of 16O+64Zn at near-barrier energies

    Elastic and inelastic scattering angular distributions were measured for the 16O+64Zn reaction at bombarding energies close to the Coulomb barrier. The experimental data were analyzed within the optical model and coupled-channel model. An extended dispersion relation of integral quantities using a Gaussian weight was applied, instead of the normal relationship. Within this frame, the optical model parameters obtained from the data are in agreement with the dispersion relation and show the threshold anomaly at energies close to the Coulomb barrier. Analysis of the inelastic scattering angular distributions leads to some indications that an inelastic threshold anomaly is beginning to develop at energies lower than the ones for which our data were taken. copyright 1996 The American Physical Society

  13. Quadrupole moment of the first 2/sup +/ excited state in /sup 64/Zn

    Salem-Vasconcelos, S.; Bechara, M.J.; Hirata, J.H.; Dietzsch, O.

    1988-11-01

    The Coulomb excitation probability of the first 2/sup +/ state of /sup 64/Zn was measured observing the backscattered ions of /sup 4/He, /sup 16/O, and /sup 18/O. The static quadrupole moment Q/sub =/ and the reduced transition probability B(E2;O/sup +/..-->..2/sup +/) have been determined using the reorientation effect. It is found that Q/sub =/ = -0.32 +- 0.06 e b (-0.26 +- 0.06 e b) for constructive (destructive) interference involving the second 2/sup +/ state, and that B(E2;O/sup +/..-->..2/sup +/) = 0.168 +- 0.004e/sup 2/b/sup 2/, for both cases.

  14. Elastic scattering of the halo nucleus 11Be on 64Zn

    The elastic scattering cross-sections for the halo nucleus 11Be incident on 64Zn in the vicinity of Coulomb barrier are calculated using the microscopic double folding model. The parametrized densities taking into account for the halo part are folded with the effective nucleon-nucleon interaction (M3Y) to yield the microscopic double folded potential. The dynamic polarization potential (DPP) has been computed using the dipole strength distribution from the cluster model and from experiments. The calculated differential cross-section with the inclusion of the imaginary part of the dynamic polarization potential to the double folded potential shows a significant suppression of the differential cross-section in the Coulomb-nuclear interference region. This indicates that DPP effects due to B(E1) distribution are crucial in explaining the elastic scattering cross section of halo nuclei at incident energies in the vicinity of Coulomb barrier

  15. High spin levels in 62Zn, 64Zn, 66Zn, and 68Zn

    Investigation by in-beam gamma spectroscopy of high-spin states in the even zinc isotopes has been made using the Ni(α,2nγ)Zn reactions at Esub(α) approximately equal to 30MeV for 62Zn, 64Zn and 66Zn, and the 65Cu(α,pγ) reaction at Esub(α) approximately equal to 18MeV for 68Zn. The high-spin states feeding by varying the incident particles: p,3He,α,12C is discussed. It is pointed out that the gsub(9/2) orbital plays an important role in the structure of the high-spin states. The variation of the inertia momentum throughout the yrast line shows a backbending behavior and a shape transition associated to the occurence, for J>6, of rotational states is speculated

  16. Gamma-ray spectroscopy for investigation of the co-existence of deformed and spherical states in the magic nucleus of 114Sn

    The term diagram of the 50114Sn64 magic nucleus could be enlarged by 77 newly identified gamma transitions and 47 novel energy levels identified by way of a gamma-gamma coincidence measurement using the OSIRIS hexahedral spectrometer and by means of the high-spin reaction of 100Mo(18O,4n)114Sn at an injection energy of E(18O) = 70 MeV. Spins up to an excitation energy of ∝ 11.2 MeV and up to a maximum spin of 23 h have been occupied. For identification of the multipolarities of low-intensity γ-transitions which deplete the high-spin states, γγ-angular correlations have been evaluated, and 26 energy levels could be clearly assigned for the first time to measured spin values. For an interpretation of further nuclear structural states of 114Sn theoretical calculation have been made based on the shell model of nucleus. (orig./DG)

  17. Evidence for the Jacobi shape transition in hot 46Ti

    Maj, A; Bracco, A; Camera, F; Bednarczyk, P; Herskind, B; Brambilla, S; Benzoni, G; Brekiesz, M; Curien, D; De Angelis, G F; Farnea, E; Grebosz, J; Kicinska-Habior, M; Leoni, S; Meczynski, W; Million, B; Napoli, D R; Nyberg, J; Petrache, C M; Styczen, J; Wieland, O; Zieblinski, M; Zuber, K; Dubray, N; Dudek, J; Pomorski, K

    2004-01-01

    The gamma-rays from the decay of the GDR in 46Ti compound nucleus formed in the 18O+28Si reaction at bombarding energy 105 MeV have been measured in an experiment using a setup consisting of the combined EUROBALL IV, HECTOR and EUCLIDES arrays. A comparison of the extracted GDR lineshape data with the predictions of the thermal shape fluctuation model shows evidence for the Jacobi shape transition in hot 46Ti. In addition to the previously found broad structure in the GDR lineshape region at 18-27 MeV caused by large deformations, the presence of a low energy component (around 10 MeV), due to the Coriolis splitting in prolate well deformed shape, has been identified for the first time.

  18. Evaporation residues cross-section measurements and TDHF calculations for 16O+64Zn and 32S+48Ti systems

    Investigation of dynamical effects in heavy-ion induced fusion reactions is an area of intense research. Much progress has been made in this field both on the theoretical and experimental front. In order to test this we have measured the fusion (Evaporation residue (ER)) cross-section for 16O+64Zn and 32S+48Ti systems. We report here the results on cross-section measurements and the comparison with the predictions of Time Dependent Hartree Fock (TDHF) calculations

  19. Strong Deformation Effects in Hot Rotating 46Ti

    Kmiecik, M; Brekiesz, M; Mazurek, K; Bednarczyk, P; Grebosz, J; Meczynski, W; Styczen, J; Zieblinski, M; Zuber, K; Papka, P; Beck, C; Curien, D; Haas, F; Rauch, V; Rousseau, M; Dudek, J; Schunck, N; Bracco, A; Camera, F; Benzoni, G; Wieland, O; Herskind, B; Farnea, E; De Angelis, G

    2007-01-01

    Exotic-deformation effects in 46Ti nucleus were investigated by analysing the high-energy gamma-ray and the alpha-particle energy spectra. One of the experiments was performed using the charged-particle multi-detector array ICARE together with a large volume (4"x4") BGO detector. The study focused on simultaneous measurement of light charged particles and gamma-rays in coincidence with the evaporation residues. The experimental data show a signature of very large deformations of the compound nucleus in the Jacobi transition region at the highest spins. These results are compared to data from previous experiments performed with the HECTOR array coupled to the EUROBALL array, where it was found that the GDR strength function is highly fragmented, strongly indicating a presence of nuclei with very large deformation.

  20. Evidence for the Jacobi shape transition in hot 46Ti

    The γ-ras from the decay of the GDR in the compound nucleus reaction 18O+28Si at bombarding energy of 105 MeV have been measured in an experiment using a setup consisting of the combined EUROBALL IV, HECTOR and EUCLIDES arrays. The shape of the rotating compound nucleus, 46Ti, is expected to undergo the Jacobi transition around spin 28 ℎ. A comparison of the GDR lineshape data with the predictions of the thermal shape fluctuation model, based on the most recent rotating liquid drop LSD calculations, shows evidence for such Jacobi shape transition. In addition to the previously found broad structure in the GDR lineshape region at 18-25 MeV caused by large deformations, the presence of a low energy component (around 10 MeV), due to the Coriolis splitting in prolate, well deformed shape has been identified for the first time

  1. Elastic scattering and direct reactions of the 1n halo 11Be nucleus on 64Zn near the barrier

    Scuderi, V.; Di Pietro, A.; Acosta Sánchez, Luis Armando; Amorini, F.; Borge, M. J. G.; Figuera, P; Fisichella, M.; Fraile, L. M.; Gómez Camacho, Joaquín; Jeppesen, H.; Lattuada, M.; Martel Bravo, Ismael; Milin, M.; Musumarra, A.; Papa, M.

    2012-01-01

    Elastic scattering and direct reactions have been studied for the collisions induced by the three Beryllium isotopes 9,10,11Be, on a medium mass 64Zn target at energies near the Coulomb barrier. The elastic-scattering angular distribution of the 11Be halo nucleus shows a deviation from the classical Fresnel type diffraction behavior in the Coulomb-nuclear interference peak angular region. The deduced total reaction cross-sections for the 11Be collision is more than a factor of ...

  2. Comparison of the effects of couplings to breakup channels in reactions induced by {sup 6}Li and {sup 6}He on the same {sup 64}Zn target

    Fernández-García, J. P., E-mail: fernandez@lns.infn.it; Di Pietro, A.; Figuera, P.; Fisichella, M. [INFN, Laboratori Nazionali del Sud, via S. Sofia 62, 1-95123 Catania (Italy); Lattuada, M.; Musumarra, A.; Pellegriti, M. G.; Scuderi, V.; Torresi, D. [INFN, Laboratori Nazionali del Sud, via S. Sofia 62, 1-95123 Catania (Italy); Dipartamento di Fisica e Astronomia, via S. Sofia 64, I-95123 Catania (Italy); Moro, A. M. [Departamento de FAMN, Universidad de Sevilla, Apartado 1065, E-41080 Seville (Spain); Zadro, M. [Ruder Bošković Institute, Bijenička cesta 54, HR-10000 Zagreb (Croatia)

    2015-10-15

    The experimental elastic scattering angular distributions for the weakly bound nuclei {sup 6,7}Li and for the halo nucleus {sup 6}He on the same {sup 64}Zn target at several energies around the Coulomb barrier were measured at the Laboratori Nazionali del Sud (LNS, Italy) and at the Cyclotron Research Center, Louvain La Neuve (Belgium), respectively. The measured elastic scattering angular distributions of these three systems at the same center of mass energy have been compared. The experimental data of the {sup 6,7}Li+ {sup 64}Zn systems have been analyzed within the CDCC method, while the {sup 6}He+{sup 64}Zn data have been compared with both both CDCC and CRC calculations.

  3. Elastic and inelastic scattering of {sup 16}O+{sup 64}Zn at near-barrier energies

    Tenreiro, C.; Acquadro, J.C.; Freitas, P.A.; Liguori Neto, R. [Universidade de Sao Paulo, IFUSP Laboratorio Pelletron, C.P. 20516-01498-970, Sao Paulo (Brazil); Ramirez, G.; Cuevas, N. [Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 1 (Chile); Gomes, P.R.; Cabezas, R.; Anjos, R.M. [Departamento de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Niteroi, R. J., 24210 (Brazil); Copnell, J. [University of Manchester, Physics Department, Schuster Laboratories, Manchester M13 9PL (United Kingdom)

    1996-06-01

    Elastic and inelastic scattering angular distributions were measured for the {sup 16}O+{sup 64}Zn reaction at bombarding energies close to the Coulomb barrier. The experimental data were analyzed within the optical model and coupled-channel model. An extended dispersion relation of integral quantities using a Gaussian weight was applied, instead of the normal relationship. Within this frame, the optical model parameters obtained from the data are in agreement with the dispersion relation and show the threshold anomaly at energies close to the Coulomb barrier. Analysis of the inelastic scattering angular distributions leads to some indications that an inelastic threshold anomaly is beginning to develop at energies lower than the ones for which our data were taken. {copyright} {ital 1996 The American Physical Society.}

  4. Coupled-channel analysis for 20.4 MeV energy of p-^{64}Zn inelastic scattering

    Harun Yücel; Müşfik Taşan

    2012-02-01

    In this study, a coupled-channel (CC) analysis of the elastic and the inelastic scattering of 20.4 MeV polarized protons from a 64Zn target leading to the deformed 2+, $3^−$, $2^+_2$ states was performed. The CC potential parameters and the deformation parameters of the excited states corresponding to the best fit to the experimental differential cross-sections and the analysing powers data were determined. For $2^+_2$ excited state, a mixed type was used and a good fit to the data was provided. The CC calculation results were compared to the pure distorted wave Born approximation (DWBA) calculation results which were calculated using the new parameters. All calculations were conducted using the computer code ECIS06.

  5. MICROSTRUCTURE OF Mg-6.4Zn-1.1Y ALLOY FABRICATED BY RAPID SOLIDIFICATION AND RECIPROCATING EXTRUSION

    Z.M. Zhang; C.J. Xu; X.F. Guo

    2008-01-01

    In order to explore the methods to prepare high-strength quasicrystal-reinforced magnesium alloys, the flakes of rapidly solidified Mg-6.4Zn-1.1 Y magnesium alloy with a thickness of 50-60 um were obtained by a melt spinning single-roller device, and the flakes were then processed into rods by reciprocating extrusion and direct extrusion. The microstructure of the alloy was analyzed by optical microscope and SEM, and the constituent phases were identified by XRD. Phase transformation and its onset temperature were determined by differential thermal analyzer (DTA). The analysis result shows that rapid solidification for Mg-6.4Zn-1.1Y alloy can inhibit the eutectic reactions, broaden the solid solubility of Zn in a-Mg solute solution, and impede the formation of Mg3 Y2 Zn3 and MgZn2 compounds, and thus help the icosahedral Mg3 YZn6 quasicrystal formed directly from the melt. The mierostrueture of the flakes consists of the a-Mg solid solution and icosahedral Mg3 YZn6 quasierystal. Dense rods can be made from the flakes by two-pass reciprocating extrusion and direct extrusion. The interfaces between flakes in the rods can be welded and jointed perfectly. During the reciprocating extrusion and direct extrusion process, more Mg3 YZn6 compounds are precipitated and distributed uniformly, whereas the rods possess fine microstructures inherited from rapidly solidified flakes. The rods contain only two phases: amagnesium solid solution as matrix and fine icosahedral Mg3 YZn6 quasicrystal which disperses uniformly in the matrix.

  6. Four-body continuum-discretized coupled-channels calculations: Application to 6He+64Zn at 13.6 MeV

    The recently developed four-body continuum-discretized coupled-channels (CDCC) method, making use of the binning procedure, is applied to the reaction 6He+64Zn at 13.6 MeV (around the Coulomb barrier). Excellent agreement with available elastic data is found.

  7. SIMS depth profiling of rubber-tyre cord bonding layers prepared using 64Zn depleted ZnO

    Zinc oxide and copper/zinc sulphide layers are formed during vulcanisation and moulding of rubber to brass-coated steel tyre reinforcing cords. Previous studies have described how zinc diffuses through the rubber-brass interface to form zinc sulphide, and combines with oxygen to create zinc oxide during dezincification. The zinc is usually assumed to originate in the brass of the tyre cord, however, zinc oxide is also present in the rubber formulation. We reveal how zinc from these sources is distributed within the interfacial bonding layers, before and after heat and humidity ageing. Zinc oxide produced using 64Zn-isotope depleted zinc was mixed in the rubber formulation in place of the natural ZnO and the zinc isotope ratios within the interfacial layers were followed by secondary ion mass spectroscopy (SIMS) depth profiling. Variations in the relative ratios of the zinc isotopes during depth profiling were measured for unaged, heat-aged and humidity-aged wire samples and in each case a relatively large proportion of the zinc incorporated into the interfacial layer as zinc sulphide was shown to have originated from ZnO in the rubber compound

  8. Disappearance of flow and the in-medium nucleon-nucleon cross section for {sup 64}Zn+{sup 27}Al collisions at intermediate energies

    Zhi-Yong He [Caen Univ., 14 (France). Lab. de Physique Corpusculaire]|[Academia Sinica, Lanzhou, GS (China). Inst. of Modern Physics; Peter, J.; Angelique, J.C.; Bizard, G.; Brou, R.; Cussol, D. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire; Auger, A.; Cabot, C.; Crema, E. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Buta, A. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire]|[Institute of Atomic Physics, Bucharest (Romania)] [and others

    1996-09-01

    Experimental measurement and theoretical comparison of collective flow can give important information about the nuclear equation of state (EOS) and the in-medium nucleon-nucleon cross section. Experimental measurements of {sup 64}Zn+{sup 27}Al collision from 35 to 79 MeV/u with the 4{pi} array MUR=TONNEAU are presented. The results are compared to BUU calculations. (K.A.).

  9. Cross section measurement for 45Sc(p,γ)46Ti

    The cross section of the reaction 45Sc(p,γ)46Ti has been measured over the bombarding energy range 0.7 - 4.2 MeV. This energy range is appropriate for calculating the interaction rate in a stellar interior over the temperature range 109 - 1010K. The results are compared with predictions of the statistical model of nuclear reactions. Stellar interaction rates are calculated

  10. Measurement of the thermal cross section of the reaction 64Zn(n,γ)65Zn in a mixed neutron flux

    Zinc is an element that is present in a great variety of biological and geological samples.For its determination by Instrumental Neutron Activation Analysis, the reaction 64Zn(n,γ)65Zn is used, due to the long half life of the reaction product, the target's bigger isotopic abundance, and an easily measurable 1115 keV main gamma line.In a recent evaluation of thermal cross sections and resonance integrals, a thermal cross section value that is 44.7% bigger than the previous evaluation has been published by the same reference.This difference is not within reported uncertainties.Besides, the relative uncertainty of the new evaluation is much bigger than the one corresponding to the previous evaluation.The adoption of the thermal cross section corresponding to different evaluations may imply, in the case of an irradiation in the peripheral I 6 position at the R A-6 reactor, discrepancies of about 43% in the calculated concentrations.These inconsistencies were evident during the irradiation of certified standard materials.This motivated the measurement of the thermal cross section for the reaction 64Zn(n,γ)65Zn in the I 6 position at the R A-6 reactor.For the analysis of results, a code was written in order to calculate correction factors from an accurate characterization of the neutron spectrum.The thermal cross section value of the reaction 64Zn(n,γ)65Zn measured is (0.76± 0.03) b

  11. Measurements of the 64Zn(n,a)61Ni cross section at En=5.0-6.75 MeV

    Gledenov, Yu M; Sedyshev, P V; Oprea, A; Chen, Z; Chen, Y; Yuan, J; Zhang, G; Tang, G; Khuukhenkhuu, G; Szalanski, P; Gledenov, Yu.M.

    2002-01-01

    The experiment of determination of the 64Zn(n,a)61Ni reaction cross section in the 5.0-6.75 MeV neutron energy range was performed at the 4.5 MV Van de Graaf accelerator at the Institute of Heavy Ion Physics, Peking University, Beijing. Double section ionization chamber with grid was used for direct registration of the reaction products. The cross sections and angular distributions were extracted from the experimental data. The obtained values were compared with the results of other authors and theoretical estimations. The analysis of the experimental data and model calculations were carried out.

  12. Measurements of the 64Zn(n,a)61Ni cross section at En=5.0-6.75 MeV

    Gledenov, Yu. M.; Sedysheva, M. V.; Sedyshev, P. V.; Oprea, A.; Chen, Z.; Chen, Y; Yuan, J.; Zhang, G.; Tang, G.; Khuukhenkhuu, G.; Szalanski, P.

    2002-01-01

    The experiment of determination of the 64Zn(n,a)61Ni reaction cross section in the 5.0-6.75 MeV neutron energy range was performed at the 4.5 MV Van de Graaf accelerator at the Institute of Heavy Ion Physics, Peking University, Beijing. Double section ionization chamber with grid was used for direct registration of the reaction products. The cross sections and angular distributions were extracted from the experimental data. The obtained values were compared with the results of other authors a...

  13. Measurement of Excitation Functions of 64Zn (n,p) 64Cu, 64Zn(n, Zn) 63Zn, 51V(n,alpha) 48Sc and 48Ti(n,p) 48Sc Reactions, Around 14-MeV Energy

    The cross-sections of the reactions 64Zn (n,p) 64Cu, 64Zn(n,Zn) 63Zn, 51V(n,alpha)48Sc and 48Ti (n,p) 48Sc around 14-MeV show large discrepancies in the literature. Accurate measurements of these excitation functions were made in the energy range 13.63-14.73 MeV applying the neutron activation technique using a neutron generator. Results were obtained with a statistical error less than 7%. These measured excitation functions were used to check the statistical multistep compound/ statistical multistep direct (SMC/SMD) reaction models using EXIFON code. The calculations are in good agreement with the measurements, specially for the (n,Zn) reactions

  14. Statistical and direct aspects of 64Zn (γ,n) and (γ,np) decay channels in the giant dipole resonance and quasideuteron energy regions

    The investigation of statistical and direct aspects related to the (γ,n) and (γ,np) decay channels of 64Zn in the giant dipole resonance (GDR) and quasideuteron (QD) energy regions was performed by a trial function fitting to the respective (e,n) and (e,np) electrodisintegration yields measured by residual activity. The trial function incorporated the GDR and QD models to describe the initial photoabsorption mechanism and the geometry dependent hybrid exciton model used in the ALICE/LIVERMORE-82 code to calculate the relevant branching ratios, with the E1 virtual photon spectra being calculated in the distorted wave Born approximation. We compared our results for the (γ,n) cross section with other existing experimental measurements, and the long-standing normalization issue among different laboratories was revisited and addressed. We obtained for the first time the absolute (γ,np) cross section from threshold to 60 MeV. We succeeded in separating statistical and direct contributions of the (γ,np) process, the latter being remarkably well described by the QD model in the interval 40-60 MeV. A possible direct contribution for the (γ,n) decay in the GDR is also addressed. Finally, the total photoabsorption cross section of 64Zn was reevaluated up to 21 MeV, and the results were compared with previous estimates performed by other groups

  15. A Comprehensive Theoretical Analysis of 6,7Li + 64Zn Elastic Scattering in a Wide Angular Range Around the Coulomb Barrier

    Ibraheem, Awad A.; Aygun, M.

    2016-08-01

    In this paper, the elastic scattering angular distributions of 6,7Li on 64Zn have been investigated by using various nuclear potentials. For this, we use the phenomenological Woods-Saxon potential, the real double folding potential with the density-independent M3Y effective interaction supplemented with an imaginary part in Woods-Saxon form and the double folding potentials multiplied with a normalization factor of the real and imaginary parts via the density-independent and CDM3Y6 density-dependent versions of the M3Y effective interaction have been used. The results have been compared with each other as well as with the experimental data. It has been observed that the agreement between the theoretical results and earlier reported data is perfect. Finally, the change of the total reaction cross sections with energy has been investigated.

  16. A Comprehensive Theoretical Analysis of 6,7Li + 64Zn Elastic Scattering in a Wide Angular Range Around the Coulomb Barrier

    Ibraheem, Awad A.; Aygun, M.

    2016-06-01

    In this paper, the elastic scattering angular distributions of 6,7Li on 64Zn have been investigated by using various nuclear potentials. For this, we use the phenomenological Woods-Saxon potential, the real double folding potential with the density-independent M3Y effective interaction supplemented with an imaginary part in Woods-Saxon form and the double folding potentials multiplied with a normalization factor of the real and imaginary parts via the density-independent and CDM3Y6 density-dependent versions of the M3Y effective interaction have been used. The results have been compared with each other as well as with the experimental data. It has been observed that the agreement between the theoretical results and earlier reported data is perfect. Finally, the change of the total reaction cross sections with energy has been investigated.

  17. Reconstructed primary fragments and symmetry energy, temperature and density of the fragmenting source in $^{64}$Zn + $^{112}$Sn at 40 MeV/nucleon

    Liu, X; Wada, R; Huang, M; Zhang, S; Ren, P; Chen, Z; Wang, J; Xiao, G Q; Han, R; Liu, J; Shi, F; Rodrigues, M R D; Kowalski, S; Keutgen, T; Hagel, K; Barbui, M; Zheng, H; Bonasera, A; Natowitz, J B

    2014-01-01

    Symmetry energy, temperature and density at the time of the intermediate mass fragment formation are determined in a self-consistent manner, using the experimentally reconstructed primary hot isotope yields and anti-symmetrized molecular dynamics (AMD) simulations. The yields of primary hot fragments are experimentally reconstructed for multifragmentation events in the reaction system $^{64}$Zn + $^{112}$Sn at 40 MeV/nucleon. Using the reconstructed hot isotope yields and an improved method, based on the modified Fisher model, symmetry energy values relative to the apparent temperature, $a_{sym}/T$, are extracted. The extracted values are compared with those of the AMD simulations, extracted in the same way as that for the experiment, with the Gogny interaction with three different density-dependent symmetry energy terms. $a_{sym}/T$ values change according to the density-dependent symmetry energy terms used. Using this relation, the density of the fragmenting system is extracted first. Then symmetry energy a...

  18. Elastic and inelastic scattering of [sup 16]O and [sup 18]O ions from [sup 64]Zn at energies near the Coulomb barrier

    Salem-Vasconcelos, S.; Takagui, E.M.; Bechara, M.J.; Koide, K.; Dietzsch, O. (Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil)); Jr, A.B.N. (Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro (Brazil)); Takai, H. (Brookhaven National Laboratory, Upton, New York 11973 (United States))

    1994-08-01

    Coulomb-nuclear interference effects were investigated in the inelastic scattering of [sup 16]O and [sup 18]O by [sup 64]Zn. Measurements of elastic and inelastic angular distributions of [sup 18]O were performed at a laboratory energy of 49 MeV, over the angular range from [theta][sub lab][similar to]30[degree] to 85[degree]. The excitation functions of [sup 16]O and [sup 18]O ions were measured at incident energies between 29 and 46 MeV at [theta][sub lab]=174[degree]. The experimental angular distributions show structures which are more pronounced for projectile excitation than for target excitation. The interference minimum for the excitation of the [sup 18]O first 2[sup +] state was found to be shifted towards forward angles by approximately 5[degree] (c.m.) with respect to the distorted-wave Born approximation calculations and by approximately 3.5[degree] (c.m.) with respect to the coupled-channels calculations. A pronounced Coulomb-nuclear interference minimum was seen in the excitation of [sup 64]Zn(2[sup +]) state by inelastic scattering of [sup 16]O projectiles, whereas no pronounced minimum was observed in target excitation by [sup 18]O projectiles. The elastic scattering data were analyzed with the optical model. The inelastic differential cross sections for the excitation of the first 2[sup +] states in the target and in the [sup 18]O projectile were analyzed using the distorted-wave Born approximation and also the coupled-channels approach with collective form factors.

  19. Evidence for the Jacobi shape transition in hot {sup 46}Ti

    Maj, A.; Kmiecik, M.; Bracco, A.; Camera, F.; Bednarczyk, P.; Herskind, B.; Brambilla, S.; Benzoni, G.; Brekiesz, M.; Curien, D.; De Angelis, G.; Farnea, E.; Grebosz, J.; Kicinska-Habior, M.; Leoni, S.; Meczynski, W.; Million, B.; Napoli, D.R.; Nyberg, J.; Petrache, C.M.; Styczen, J.; Wieland, O.; Zieblinski, M.; Zuber, K.; Dubray, N.; Dudek, J.; Pomorski, K

    2004-02-09

    The {gamma}-ras from the decay of the GDR in the compound nucleus reaction {sup 18}O+{sup 28}Si at bombarding energy of 105 MeV have been measured in an experiment using a setup consisting of the combined EUROBALL IV, HECTOR and EUCLIDES arrays. The shape of the rotating compound nucleus, {sup 46}Ti, is expected to undergo the Jacobi transition around spin 28 {Dirac_h}. A comparison of the GDR lineshape data with the predictions of the thermal shape fluctuation model, based on the most recent rotating liquid drop LSD calculations, shows evidence for such Jacobi shape transition. In addition to the previously found broad structure in the GDR lineshape region at 18-25 MeV caused by large deformations, the presence of a low energy component (around 10 MeV), due to the Coriolis splitting in prolate, well deformed shape has been identified for the first time.

  20. Reconstructed primary fragments and symmetry energy, temperature and density of the fragmenting source in {sup 64}Zn+{sup 112}Sn at 40 MeV/nucleon

    Liu, X., E-mail: liuxingquan@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Lin, W. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Wada, R., E-mail: wada@comp.tamu.edu [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Huang, M. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Ren, P. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Chen, Z.; Wang, J.; Xiao, G.Q. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Zhang, S. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Han, R.; Liu, J.; Shi, F. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Rodrigues, M.R.D. [Instituto de Física, Universidade de São Paulo, Caixa Postal 66318, CEP 05389-970, São Paulo, SP (Brazil); Kowalski, S. [Institute of Physics, Silesia University, Katowice (Poland); Keutgen, T. [FNRS and IPN, Université Catholique de Louvain, B-1348 Louvain-Neuve (Belgium); Hagel, K.; Barbui, M. [Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States); Bonasera, A. [Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States); Laboratori Nazionali del Sud, INFN, via Santa Sofia, 62, 95123 Catania (Italy); Natowitz, J.B. [Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States); and others

    2015-01-15

    Symmetry energy, temperature and density at the time of the intermediate mass fragment formation are determined in a self-consistent manner, using the experimentally reconstructed primary hot isotope yields and anti-symmetrized molecular dynamics (AMD) simulations. The yields of primary hot fragments are experimentally reconstructed for multifragmentation events in the reaction system {sup 64}Zn+{sup 112}Sn at 40 MeV/nucleon. Using the reconstructed hot isotope yields and an improved method, based on the modified Fisher model, symmetry energy values relative to the apparent temperature, a{sub sym}/T, are extracted. The extracted values are compared with those of the AMD simulations, extracted in the same way as those for the experiment, with the Gogny interaction with three different density-dependent symmetry energy terms. The a{sub sym}/T values change according to the density-dependent symmetry energy terms used. Using this relation, the density of the fragmenting system is extracted first. Then symmetry energy and apparent temperature are determined in a self consistent manner in the AMD model simulations. Comparing the calculated a{sub sym}/T values and those of the experimental values from the reconstructed yields, ρ/ρ{sub 0}=0.65±0.02, a{sub sym}=23.1±0.6 MeV and T=5.0±0.4 MeV are evaluated for the fragmenting system experimentally observed in the reaction studied.

  1. The study of the components of matter collective flow in the collisions of 64 Zn on 58 Ni at 35 to 79 MeV/u

    In a nucleus-nucleus collision the collective motion of matter, emitted from the overlapping region, give information on the properties of nuclear matter out-of-equilibrium. The characteristics of this motion have been studied on the 64 Zn on 58 Ni system up to 79 MeV per nucleon, using the flow parameter and the azimuthal distributions. We studied the evolution of those quantities with the incident energy, the impact parameter and the charge of particle. The experiment has been done at GANIL using the multidetectors of light particles and fragments, Mur and Tonneau. For estimating the impact parameter, two global variables have been used: the average parallel velocity and the total perpendicular momentum. For determining the reaction plane two methods have been used: the transverse momentum analysis and the azimuthal correlation method. The results are not sensitive to the global variable or method. The measured values revealed the inversion of the direction of sideward flow. The energy of vanishing flow ranges from 55 to 75 MeV per nucleon when the impact parameter increases from 1 to 6 fm. In the same way, the aspect of the azimuthal distribution changes from in-plane to out-of-plane enhancement when the energy increases, providing with a new indication of change in the interaction dynamics. The energy of isotropic emission lies between 45 and 65 MeV per nucleon depending of the impact parameter. For alpha particles, the flow parameter and the azimuthal asymmetry are greater than for protons, due to a smaller thermal dispersion. A Landau-Vlasov model using a non-local Gogny force is able to reproduce the global characteristics experimentally observed (rapidity and transverse momentum distributions). The calculated flow and azimuthal asymmetry values reproduce the experimental ones for an incompressibility modulus near 230 MeV. The study of the dependence on nucleon-nucleon cross section in nuclear medium must be pursued. (author)

  2. Deformation Effects in Hot Rotating {sup 46}Ti Probed by the Charged Particle Emission and GDR {gamma}-Decay

    Brekiesz, M. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Maj, A. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Kmiecik, M. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Mazurek, K. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Meczynski, W. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Styczen, J. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Zuber, K. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Papka, P. [IPHC and ULP (Strasbourg I), B.P. 28 F-67037 Strasbourg Cedex 2 (France); iThemba LABS, 7129 Somerset West (South Africa); Beck, C. [IPHC and ULP (Strasbourg I), B.P. 28 F-67037 Strasbourg Cedex 2 (France); Haas, F. [IPHC and ULP (Strasbourg I), B.P. 28 F-67037 Strasbourg Cedex 2 (France); Rauch, V. [IPHC and ULP (Strasbourg I), B.P. 28 F-67037 Strasbourg Cedex 2 (France); Rousseau, M. [IPHC and ULP (Strasbourg I), B.P. 28 F-67037 Strasbourg Cedex 2 (France); Sanchez i Zafra, A. [IPHC and ULP (Strasbourg I), B.P. 28 F-67037 Strasbourg Cedex 2 (France); Dudek, J. [IPHC and ULP (Strasbourg I), B.P. 28 F-67037 Strasbourg Cedex 2 (France); Schunck, N. [H. Niewodniczanski Institute of Nuclear Physics, PAN, 31-342 Cracow (Poland); Departamento de Fisica Teorica, Universidad Autonoma de Madrid (Spain)

    2007-05-15

    The {sup 46}Ti * compound nucleus, as populated by the fusion-evaporation reaction {sup 27}Al + {sup 19}F at the bombarding energy of E {sub lab} = 144 MeV, has been investigated by charged particle spectroscopy using the multidetector array ICARE at the VIVITRON tandem facility of the IReS (Strasbourg). The light charged particles and high-energy {gamma}-rays from the GDR decay have been measured in coincidence with selected evaporation residues. The CACARIZO code, a Monte Carlo implementation of the statistical-model code CASCADE, has been used to calculate the spectral shapes of evaporated {alpha}-particles which are compared with the experimental coincident spectra. This comparison indicates the signature of large deformations (possibly superdeformed and hyperdeformed shapes) present in the compound nucleus decay. The occurrence of the Jacobi shape transition is also discussed in the framework of a newly developed rotating liquid drop model.

  3. The threshold anomaly from the simultaneous calculation of elastic scattering and fusion cross sections for the systems 9Be+144Sm and 9Be+64 Zn for energies around the barrier

    A.G. Camacho

    2008-01-01

    Full Text Available La dependencia con la energía del potencial óptico se usa para determinar la presencia de la Anomalía de Umbral en reacciones entre el proyectil débilmente ligado 9Be con 144Sm y 64Zn a energías alrededor de la barrera Coulombiana. Los parámetros del optencial óptico se encuentran mediante un ajuste X² de los datos experimentales de dispersión elástica y fusión completa. Los resultados demuestran que, en realidad la Anomalía de Umbral por Rompimiento aparece en estas reacciones. Esta conclusión concuerda con los resultados de otras reacciones en que intervienen projectiles debilmente ligados.

  4. Re-evaluation of microscopic and integral cross-section data for important dosimetry reactions. Re-evaluation of the excitation functions for the 24Mg(n,p)24Na, 32S(n,p)32P, 60Ni(n,p)60m+gCo, 63Cu(n,2n)62Cu, 65Cu(n,2n)64Cu, 64Zn(n,p)64Cu, 115In(n,2n)114mIn, 127I(n,2n)126I, 197Au(n,2n)196Au and 199Hg(n,n')199mHg reactions

    Re-evaluations of cross sections and their associated covariance matrices have been carried out for ten dosimetry reactions: - excitation functions for the 63Cu(n,2n)62Cu, 65Cu(n,2n)64Cu, 64Zn(n,p)64Cu, 115In(n,2n)114mIn and 199Hg(n,n')199mHg reactions were re-evaluated over the neutron energy range from threshold to 20 MeV; - excitation functions for the 24Mg(n,p)24Na, 32S(n,p)32P and 60Ni(n,p)60m+gCo were reevaluated in the energy range from threshold to 21 MeV; - excitation functions for the 127I(n,2n)126I and 197Au(n,2n)196Au reactions were reevaluated in the energy range from threshold to 32 and 40 MeV, respectively. Benchmark calculations performed for 235U thermal fission and 252Cf spontaneous fission neutron spectra show that the integral cross sections derived from the newly evaluated excitation functions exhibit improved agreement with related experimental data when compared with the equivalent data from the IRDF-2002 library. (author)

  5. On the Contribution of Gamma Ray Bursts to the Galactic Inventory of Some Intermediate Mass Nuclei

    Pruet, J; Surman, R; McLaughlin, G C

    2004-01-23

    Light curves from a growing number of Gamma Ray Bursts (GRBs) indicate that GRBs copiously produce radioactive Ni moving outward at fractions of the speed of light. We calculate nuclear abundances of elements accompanying the outflowing Ni under the assumption that this Ni originates from a wind blown off of a viscous accretion disk. We also show that GRB's likely contribute appreciably to the galactic inventory of {sup 42}Ca, {sup 45}Sc, {sup 46}Ti, {sup 49}Ti, {sup 63}Cu, and may be an important site for the production of {sup 64}Zn.

  6. Measurements of integral cross sections in the californium-252 fission neutron spectrum

    In a low-scattering arrangement cross sections averaged over the californium-252 spontaneous fission neutron spectrum were measured. The reactions 27Al(n,α)46Ti, 47Ti, 48Ti(n,p), 54Fe,56Fe(n,p), 58Ni(n,p), 64Zn(n,p), 115In(n,n') were studied in order to obtain a consistent set of threshold detectors used in fast neutron flux density measurements. Overall uncertainties between 2 and 2.5% could be achieved; corrections due to neutron scattering in source and samples are discussed

  7. On the Contribution of Gamma Ray Bursts to the Galactic Inventory of Some Intermediate Mass Nuclei

    Pruet, J; McLaughlin, G C; Pruet, Jason; Surman, Rebecca; Laughlin, Gail C. Mc

    2004-01-01

    Light curves from a growing number of Gamma Ray Bursts (GRBs) indicate that GRBs copiously produce radioactive Ni moving outward at fractions of the speed of light. We calculate nuclear abundances of elements accompanying the outflowing Ni under the assumption that this Ni originates from a wind blown off of a viscous accretion disk. We also show that GRB's likely contribute appreciably to the galactic inventory of 42Ca, 45Sc, 46Ti, 49Ti, 63Cu, and may be a principal site for the production of 64Zn.

  8. Study by {alpha}-particle scattering, of the collective states of closed shell nuclei with 28 neutrons, 28 and 50 protons; Etude des etats a caractere collectif des noyaux au voisinage des couches fermees par diffusion inelastique des particules {alpha}

    Bruge, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-01-01

    This report gives the results from a systematic study by 44 MeV {alpha} particle scattering on the collective states of closed shell nuclei with 28 neutrons, 28 and 50 protons especially in the energy region corresponding to the two phonon vibrational triplet. The nuclei studied are: {sup 46}Ti, {sup 48}Ti, {sup 50}Ti, {sup 52}Cr, {sup 54}Fe, {sup 56}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 62}Ni, {sup 64}Ni, {sup 112}Sn, {sup 114}Sn, {sup 116}Sn, {sup 118}Sn, {sup 120}Sn, {sup 122}Sn and {sup 124}Sn. The theoretical analysis has been made with the Austern and Blair model using a phase shift analysis of the elastic scattering. Deformation lengths {delta}{sub I} = {beta}{sub I}R and transition probabilities obtained are compared with several experimental and theoretical data. (author) [French] Ce rapport donne les resultats d'une etude systematique par diffusion de particules {alpha} de 44 MeV des etats collectifs des noyaux au voisinage des couches fermees a 28 neutrons et 28 et 50 protons, specialement dans la region correspondant au triplet vibrationnel a deux phonons. Les noyaux etudies sont: {sup 46}Ti, {sup 48}Ti, {sup 50}Ti, {sup 52}Cr, {sup 54}Fe, {sup 56}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 62}Ni, {sup 64}Ni, {sup 112}Sn, {sup 114}Sn, {sup 116}Sn, {sup 118}Sn, {sup 120}Sn, {sup 122}Sn et {sup 124}Sn. L'analyse theorique a ete faite a l'aide du modele de Austern et Blair utilisant une analyse en dephasages de la diffusion elastique. Les longueurs de deformation {delta}I = {beta}{sub I}R obtenues pour chaque niveau sont comparees a plusieurs donnees experimentales et theoriques. (auteur)

  9. Integral cross section measurements of a few threshold reactions induced by Am/Be neutrons

    Uddin, Md. Shuza; Hossain, Syed Mohammad; Rumman-Uz-Zaman, Md. [Atomic Energy Research Establishment, Dhaka (Bangladesh). Institute of Nuclear Science and Technology (INST); Spahn, Ingo; Qaim, Syed M. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Neurowissenschaften und Medizin (INM), Nuklearchemie (INM-5); Rakib-Uz-Zaman, Md. [Rajshahi Univ. (Bangladesh). Dept. of Applied Chemistry and Chemical Engineering

    2015-07-01

    Integral cross sections of the reactions {sup 46}Ti(n,p){sup 46}Sc, {sup 47}Ti(n,p){sup 47}Sc, {sup 48}Ti(n,p){sup 48}Sc, {sup 60}Ni(n,p){sup 60}Co and {sup 64}Zn(n,p){sup 64}Cu were measured with fast neutrons (E{sub n} > 1.5 MeV) from an Am/Be source. The results were compared with data calculated using the neutron spectral distribution and the excitation function of each reaction given in the data libraries ENDF/B-VII.0, IRDF-2002, JEFF-3.2 and JENDL-4.0. In general, the integral measurement and the integrated value agreed within ±4%, except for the {sup 46}Ti(n,p){sup 46}Sc reaction where JEFF-3.2 shows a deviation of 7% and the {sup 60}Ni(n,p){sup 60}Co reaction where ENDF/B-VII.0 and IRDF-2002 exhibit deviations upto 8%.

  10. A measurement of the half-life of the superallowed Fermi decay 46V(β+)46Ti and a study of some systematic errors involved

    The half-life for 46V positron decay has been determined with a high precision. Particular care has been taken to eliminate systematic effects introduced by inappropriate data analysis methods, by the presence of contaminant activities and by the occurrence of pulse pile-up in the electronic system. The final result obtained is 422.28 +- 0.23 ms, which is significantly lower than the presently accepted value. (Auth.)

  11. Fast neutron induced reaction cross sections and their systematics

    14.6 MeV Neutron induced cross-sections have been measured by the activation technique on twenty-nine nuclei. Sixty-two reactions have been studied using high resolution Ge(Li) spectroscopy and by a detailed accounting for flux variations during the irradiations. The cross-section for the 128Xe(n,p)-128I has been reported for the first time. The values determined in this work have been compared to those reported by other investigators as well as to values predicted by semi-empirical and theoretical methods. The influence of shell closure is difficult to discern, though some evidence is reported for such effects on (n,2n) reactions having threshold energies near the neutron energy. The nuclei studied in this work included: 14N, 19F, 23Na, 27Al, 31P, 45Sc, 46Ti, 50Cr, 54Fe, 28Ni, 63Cu, 65Cu, 64Zn, 66Zn, 68Zn, 69Ga, 75As, 90Zr, 92Mo, 124Xe, 126Xe, 128Xe, 130Xe, 131Xe, 132Xe, 134Xe, 136Xe, 141Pr and 144Sm. The temperature scale for the solar xenon thermometer is reexamined in terms of excitation functions for (n,γ) reactions on 127I and 133Cs. The revised scale suggests that an upper limit of approximately 1060K can be set on the temperature of the sun during the deuterium burning stage

  12. The PSIMECX medium-energy neutron activation cross-section library. Part III: Calculational methods for heavy nuclei

    The PSIMECX library contains calculated nuclide production cross-sections from neutron-induced reactions in the energy range about 2 to 800 MeV in the following 72 stable isotopes of 24 elements: 12C, 13C, 16O, 17O, 18O, 23Na, 24Mg, 25Mg, 26Mg, 27Al, 28Si, 29Si, 30Si, 31P, 32S, 33S, 34S, 36S, 35Cl, 37Cl, 39K, 40K, 41K, 40Ca, 42Ca, 43Ca, 44Ca, 46Ca, 48Ca, 46Ti, 47Ti, 48Ti, 49Ti, 50Ti, 50V, 51V, 50Cr, 52Cr, 53Cr, 54Cr, 55Mn, 54Fe, 56Fe, 57Fe, 58Fe, 58Ni, 60Ni, 61Ni, 62Ni, 64Ni, 63Cu, 65Cu, 64Zn, 66Zn, 67Zn, 68Zn, 70Zn, 92Mo, 94Mo, 95Mo, 96Mo, 97Mo, 98Mo, 100Mo, 121Sb, 123Sb, 204Pb, 206Pb, 207Pb, 208Pb, 232Th and 238U. The energy range covers essentially all transmutation channels other than capture. The majority of the selected elements are main constituents of normal materials of construction used in and around accelerator facilities and the library is, first and foremost, designed to be a tool for the estimation of their activation in wide-band neutron fields. This third report describes and discusses the calculational methods used for the heavy nuclei. The library itself has been described in the first report of this series and the treatment for the medium and light mass nuclei is given in the second. (author)

  13. The PSIMECX medium-energy neutron activation cross-section library. Part 1: Description and procedures for use

    The PSIMECX library contains calculated nuclide production cross-sections from neutron-induced reactions in the energy range about 2 to 800 MeV in the following 72 stable isotopes of 24 elements: 12C, 13C, 16O, 17O, 18O, 23Na, 24Mg, 25Mg, 26Mg, 27Al, 28Si, 29Si, 30Si, 31P, 32S, 33S, 34S, 36S, 35Cl, 37Cl, 39K, 40K, 41K, 40Ca, 42Ca, 43Ca, 44Ca, 46Ca, 48Ca, 46Ti, 47Ti, 48Ti, 49Ti, 50Ti, 50V, 51V, 50Cr, 52Cr, 53Cr, 54Cr, 55Mn, 54Fe, 56Fe, 57Fe, 58Fe, 58Ni, 60Ni, 61Ni, 62Ni, 64Ni, 63Cu, 65Cu, 64Zn, 66Zn, 67Zn, 68Zn, 70Zn, 92Mo, 94Mo, 95Mo, 96Mo, 97Mo, 98Mo, 100Mo, 121Sb, 123Sb, 204Pb, 206Pb, 207Pb, 208Pb, 232Th and 238U. The energy range covers essentially all transmutation channels other than capture. The majority of the selected elements are principal constituents of normal materials of construction used in and around accelerator facilities and the library is, first and foremost, designed to be a tool for the estimation of their activation in wide-band neutron fields. This first report, from a set of three, describes the form and usage of the library; the other two reports document the calculational methods. The present organisation of the library is the author's first idea and adequate for the intended use (activation calculations); being machine readable, translation of the library into other formats is straightforward. (author)

  14. ZZ KAFAX-F31, 150 and 12 Groups Cross Section Library in MATXS Format based on JEFF-3.1 for Fast Reactors

    1 - Description: Format: MATXS, 142 nuclides processed with NJOY99.245. Number of groups: 150 neutron-, 12 photon-groups. 142 nuclides: H-1, H-2, He-3, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-nat, N-14, N-15, O-16, F-19, Na-23, Mg-24, Mg-25, Mg-26, Al-27, Si-28, Si-29, Si-30, P-31, Cl-35, Cl-37, Ar-40, K-39, K-40, K-41, Ca-40, Ca-42, Ca-43, Ca-44, Ca-46, Ca-48, Ti-46, Ti-47, Ti-48, Ti-49, Ti-50, V-nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Cu-63, Cu-65, Ga-nat, Y-89, Zr-90, Zr-91, Zr-92, Zr-93, Zr-94, Zr-95, Zr-96, Nb-93, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, Mo-98, Mo-99, Mo-100, Ag-107, Ag-109, Cd-106, Cd-108, Cd-110, Cd-111, Cd-112, Cd-113, Cd-114, Cd-115m, Cd-116, Sn-112, Sn-114, Sn-115, Sn-116, Sn-117, Sn-118, Sn-119, Sn-120, Sn-122, Sn-123, Sn-124, Sn-125, Sn-126, Eu-151, Eu-153, Gd-152, Gd-154, Gd-155, Gd-156, Gd-157, Gd-158, Gd-160, W-182, W-183, W-184, W-186, Re-185, Re-187, Au-197, Pb-206, Pb-207, Pb-208, Bi-209, Th-232, Pa-233, U-233, U-234, U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, Am-242, Am-242m, Am-243, Cm-242, Cm-243, Cm-244, Cm-245, Cm-246. Origin: JEFF-3.1. Weighting spectrum: 300, 600, 900, 1200 K. The KAFAX-F31 is a MATXS-format, 150-group neutron and 12-group photon cross section library for fast reactors based on JEFF-3.1. This library was originally generated for the KALIMER (Korea Advanced LIquid Metal Reactor) core analyses. It includes 142 nuclide data (Table 1) processed by the NJOY99.245 code patched with NEA020. The library can be utilized to generate the problem-dependent group constants for neutron and/or photon transport calculations through the DANTSYS, DOORS, or PARTISN code systems. 2 - Methods: The KAFAX-F31 was generated at 300, 600, 900, and 1200 K. It contains the self-shielded cross sections for 5 to 10 background cross sections depending on the nuclides. The neutron group structure consists of one-eighth lethargy widths in almost

  15. ZZ KAFAX-E70, 150 and 12 Groups Cross Section Library in MATXS Format based on ENDF/B-VII.0 for Fast Reactors

    1 - Description: Format: MATXS, 144 nuclides processed with NJOY99.245. Number of groups: 150 neutron-, 12 photon-groups. 144 nuclides: H-1, H-2, He-3, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-nat, N-14, N-15, O-16, F-19, Na-23, Mg-24, Mg-25, Mg-26, Al-27, Si-28, Si-29, Si-30, P-31, Cl-35, Cl-37, Ar-40, K-39, K-40, K-41, Ca-40, Ca-42, Ca-43, Ca-44, Ca-46, Ca-48, Ti-46, Ti-47, Ti-48, Ti-49, Ti-50, V-nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Cu-63, Cu-65, Ga-69, Ga-71, Y-89, Zr-90, Zr-91, Zr-92, Zr-93, Zr-94, Zr-95, Zr-96, Nb-93, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, Mo-98, Mo-99, Mo-100, Ag-107, Ag-109, Cd-106, Cd-108, Cd-110, Cd-111, Cd-112, Cd-113, Cd-114, Cd-115m, Cd-116, Sn-112, Sn-113, Sn-114, Sn-115, Sn-116, Sn-117, Sn-118, Sn-119, Sn-120, Sn-122, Sn-123, Sn-124, Sn-125, Sn-126, Eu-151, Eu-153, Gd-152, Gd-154, Gd-155, Gd-156, Gd-157, Gd-158, Gd-160, W-182, W-183, W-184, W-186, Re-185, Re-187, Au-197, Pb-206, Pb-207, Pb-208, Bi-209, Th-232, Pa-233, U-233, U-234, U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, Am-242, Am-242m, Am-243, Cm-242, Cm-243, Cm-244, Cm-245, Cm-246. Origin: ENDF/B-VII.0. Weighting spectrum: 300, 600, 900, 1200 k. The ZZ-KAFAX-E70 is a MATXS-format, 150-group neutron and 12-group photon cross section library for fast reactors based on ENDF/B-VII.0. This library was originally generated for the KALIMER (Korea Advanced Liquid Metal Reactor) core analyses. It includes 144 nuclide data processed with the NJOY99.245 code patched with NEA020. The library can be used to generate the problem-dependent group constants for neutron and/or photon transport calculations through the DANTSYS, DOORS, or PARTISN code systems. 2 - Methods: The KAFAX-E70 was generated at 300, 600, 900, and 1200 K. It contains the self-shielded cross sections for 5 to 10 background cross sections depending on the nuclides. The neutron group structure consists of one-eighth lethargy

  16. ZZ KAFAX-J33, 150 and 12 Groups Cross Section Library in MATXS Format based on JENDL-3.3 for Fast Reactors

    1 - Description: Format: MATXS, 136 nuclides processed with NJOY99.245. Number of groups: 150 neutron-, 12 photon-groups. 136 Nuclides: H-1, H-2, He-3, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-nat, N-14, N-15, O-16, F-19, Na-23, Mg-24, Mg-25, Mg-26, Al-27, Si-28, Si-29, Si-30, P-31, Cl-35, Cl-37, Ar-40, K-39, K-40, K-41, Ca-40, Ca-42, Ca-43, Ca-44, Ca-46, Ca-48, Ti-46, Ti-47, Ti-48, Ti-49, Ti-50, V-nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Cu-63, Cu-65, Ga-69, Ga-71, Y-89, Zr-90, Zr-91, Zr-92, Zr-93, Zr-94, Zr-95, Zr-96, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, Mo-98, Mo-99, Mo-100, Ag-107, Ag-109, Cd-106, Cd-108, Cd-110, Cd-111, Cd-112, Cd-113, Cd-114, Cd-116, Sn-112, Sn-114, Sn-115, Sn-116, Sn-117, Sn-118, Sn-119, Sn-120, Sn-122, Sn-123, Sn-124, Sn-126, Eu-151, Eu-153, Gd-152, Gd-154, Gd-155, Gd-156, Gd-157, Gd-158, Gd-160, W-182, W-183, W-184, W-186, Pb-206, Pb-208, Bi-209, Th-232, Pa-233, U-233, U-234, U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, Am-241, Am-242, Am-242m, Am-243, Cm-242, Cm-243, Cm-244, Cm-245, Cm-246. Origin: JENDL-3.3. Weighting spectrum: 300, 600, 900, 1200 K. The KAFAX-J33 is a MATXS-format, 150-group neutron and 12-group photon cross section library for fast reactors based on JENDL-3.3. This library was originally generated for the KALIMER (Korea Advanced LIquid Metal Reactor) core analyses. It includes 136 nuclide data processed by the NJOY99.245 code patched with NEA020. The library can be utilized to generate the problem-dependent group constants for neutron and/or photon transport calculations through the DANTSYS, DOORS, or PARTISN code systems. 2 - Methods: The KAFAX-J33 was generated at 300, 600, 900, and 1200 K. It contains the self-shielded cross sections for 5 to 10 background cross sections depending on the nuclides. The neutron group structure consists of one-eighth lethargy widths in almost all the energy ranges, except between 1 and 10 keV in

  17. Zinc separation by using a liquid membrane

    We have performed the isotopic separation of 64Zn and 66Zn by using a liquid membrane with chloroform diluent and dicyclohexano - 18 - crown - 6 as carrier. The isotopic separation factor was the same as for liquid-liquid extraction

  18. Zinc isotope separation in acetone by displacement chromatography using benzo-15-crown-5 resin

    Zinc isotope separation was studied by column chromatographies using resorcinol-formaldehyde-resin grafted with benzo-15-crown-5 in the porous silica beads. Chromatography was performed in a break-through manner by feeding the acetone solution of zinc chloride into the columns. Zinc isotopic abundance ratios of 66Zn/64Zn and 68Zn/64Zn were measured by ICP-MS. It has been found that the heavier isotopes are preferentially enriched at the front boundary region. This result proves 64Zn depleted zinc can be obtained by collecting the effluents of front boundary region. The separation coefficient (ε) observed by five meters migration treatment is 0.81 x 10-3 for the isotopic pair of 68Zn/64Zn at 25 deg C and higher separation coefficient was obtained from more concentrated zinc chloride solution. (author)

  19. Role of projectile breakup in {sup 6}He and {sup 6}Li induced fusion reactions around barrier energies

    Kumari, Anju; Kharab, Rajesh, E-mail: kharabrajesh@rediffmail.com

    2015-09-15

    The influence of projectile breakup on fusion cross section for {sup 6}He + {sup 209}Bi, {sup 6}He + {sup 64}Zn, {sup 6}Li + {sup 209}Bi and {sup 6}Li + {sup 64}Zn reactions at near barrier energies is studied within the framework of quantum diffusion approach. The breakup does not affect the fusion induced by {sup 6}He, whereas a significant suppression for {sup 6}Li induced reaction is observed in below barrier energy region.

  20. Overview

    The year 2003 can be called a real breakthrough for our Institute. We managed to have our Institute transferred to the Polish Academy of Sciences. Furthermore, we succeeded in joining several programmes of the EU. These programmes are usually oriented towards improving the quality of life and applied research. Our scientific activities throughout 2003 led to 325 publications. In addition, we published 210 conference reports and scientific articles. In the field of particle physics the outstanding result was precise determination of the φ1 angle of the unitarity triangle, sin2φ1 0.733±0.057, in the CP violation studies based on B-mesons decays. This result was the outcome of the Belle collaboration. Here, our contribution was the Si Vertex Detector. An interesting result was obtained in the studies of the B0→φK0s decay driven by the b→sss transition. The time-dependent CP asymmetry in this channel measured with high statistics hinted at the CP asymmetry being inconsistent with the Standard Model (SM) prediction. This may be a sign of new physics. In central Au + Au collisions at 200 GeV/nucleon pair, the Phobos group discovered creation of a new type of highly excited hadronic matter which strongly absorbs the jets. This result indicates that a sort of critical state for dense excited hadronic matter has been reached. The Coriolis splitting of the GDR components in 46Ti was observed, and a link to the low excited states of 42Co established. This may point to a kind of memory in the compound nucleus. The spectra of pions from hadronic reaction were calculated using unintegrated parton distributions known from lepton inelastic scattering experiments. It was shown that the spectra cannot be explained by the gluonic mechanism only. Complete Two-Loop Bosonic contributions to the Muon Lifetime in the Standard Model were calculated. These results will serve as a test of the SM in future e+e- colliders. Within the Na49 collaboration the existence of the S=-2, Q =-2

  1. ZZ MATXSLIBJ33, JENDL-3.3 based, 175 N-42 photon groups (VITAMIN-J) MATXS library for discrete ordinates multi-group

    1 - Description of program or function: JENDL-3.3 based, 175 neutron-42 photon groups (VITAMIN-J) MATXS library for discrete ordinates multi-group transport codes. Format: MATXS. Number of groups: 175 neutron, 42 gamma-ray. Nuclides: 337 nuclides contained in JENDL-3.3: H-1, H-2, He-3, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-Nat, N-14, N-15, O-16, F-19, Na-23, Mg-24, Mg-25, Mg-26, Al-27, Si-28, Si-29, Si-30, P-31, S-32, S-33, S-34, S-36, Cl-35, Cl-37, Ar-40, K-39, K-40, K-41, Ca-40, Ca-42, Ca-43, Ca-44, Ca-46, Ca-48, Sc-45, Ti-46, Ti-47, Ti-48, Ti-49, Ti-50, V-Nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Cu-63, Cu-65, Ga-69, Ga-71, Ge-70, Ge-72, Ge-73, Ge-74, Ge-76, As-75, Se-74, Se-76, Se-77, Se-78, Se-79, Se-80, Se-82, Br-79, Br-81, Kr-78, Kr-80, Kr-82, Kr-83, Kr-84, Kr-85, Kr-86, Rb-85, Rb-87, Sr-86, Sr-87, Sr-88, Sr-89, Sr-90, Y-89, Y-91, Zr-90, Zr-91, Zr-92, Zr-93, Zr-94, Zr-95, Zr-96, Nb-93, Nb-94, Nb-95, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, Mo-98, Mo-99, Mo-100, Tc-99, Ru-96, Ru-98, Ru-99, Ru-100, Ru-101, Ru-102, Ru-103, Ru-104, Ru-106, Rh-103, Rh-105, Pd-102, Pd-104, Pd-105, Pd-106, Pd-107, Pd-108, Pd-110, Ag-107, Ag-109, Ag-110m, Cd-106, Cd-108, Cd-110, Cd-111, Cd-112, Cd-113, Cd-114, Cd-116, In-113, In-115, Sn-112, Sn-114, Sn-115, Sn-116, Sn-117, Sn-118, Sn-119, Sn-120, Sn-122, Sn-123, Sn-124, Sn-126, Sb-121, Sb-123, Sb-124, Sb-125, Te-120, Te-122, Te-123, Te-124, Te-125, Te-126, Te-127m, Te-128, Te-129m, Te-130, I-127, I-129, I-131, Xe-124, Xe-126, Xe-128, Xe-129, Xe-130, Xe-131, Xe-132, Xe-133, Xe-134, Xe-135, Xe-136, Cs-133, Cs-134, Cs-135, Cs-136, Cs-137, Ba-130, Ba-132, Ba-134, Ba-135, Ba-136, Ba-137, Ba-138, Ba-140, La-138, La-139, Ce-140, Ce-141, Ce-142, Ce-144, Pr-141, Pr-143, Nd-142, Nd-143, Nd-144, Nd-145, Nd-146, Nd-147, Nd-148, Nd-150, Pm-147, Pm-148, Pm-148m, Pm-149, Sm-144, Sm-147, Sm-148, Sm-149, Sm-150, Sm-151, Sm-152, Sm-153, Sm-154, Eu-151, Eu-152, Eu-153, Eu-154, Eu-155, Eu

  2. Zinc isotope separation in acetone by displacement chromatography using benzo-15-crown-5 resin

    Zinc is considered as a useful material for cooling water treatment in light water plants. Injection of 64Zn depleted Zinc is expected to further reduce the radiation in the reactor water system. For such a purpose of Zinc isotope separation, chemical exchange method has been studied. Breakthrough methods of chromatography experiments were performed. 0.5 mol/dm3 ZnCl2 dissolved in acetone solution was fed to glass columns packed with benzo-15-crown-5 resin at 35 degree C. The effluent was collected in fractions of which zinc concentration was determined by atomic adsorption spectrometer and isotope ratio was measured by ICP-MS. Observed enrichment ratios defined as, (iZn/64Zn)sample/ (iZn/64Zn)original, where i=66,68, are plotted in Figure. From the results of experiment, it was confirmed that heavier zinc is preferentially enriched in the eluted samples of front band regions. The separation coefficient (ε) for 66Zn/64Zn and 68Zn/64Zn of five meters migration was obtained as 5.2 x 10-4 and 8.1 x 10-4, respectively. The error is estimated to be 20% of the values.

  3. Zinc isotope separation with crown ether by column chromatography

    Depleted 64Zn is a new useful material and can be widely used in the cooling water treatment in light water nuclear power plants. In the present work, column chromatographic zinc isotope separation was performed by crown ether resin which was synthesized by ourselfs, the experimental results shown that benzo-15-crown-5 resin could effectively separate the zinc isotopes. High temperature could improve the separation coefficient, while the migration distance has no effect on separation coefficient. The height equivalent to a theoretical plate increase with the increasing of the migration distance. The separation coefficients (68Zn/64Zn=6.03 x 10-4, 66Zn/64Zn=3.52 x 10-4, respectively) and the height equivalent to a theoretical plate (0.204 cm) were obtained by 20 meters chromatographic operation with the temperature of 328 K. (authors)

  4. Spin distribution as a probe to investigate the dynamical effects in fusion reactions

    Kaur Maninder

    2015-01-01

    Full Text Available The spin distributions are measured for the compound nucleus 80Sr populated in the reactions 16O+64Zn and 32S+48Ti. The comparison of the experimental results for both the systems shows that the mean γ-ray multiplicity values for the system 32S+48Ti are lower than those for 16O+64Zn. The spin distribution of the compound nucleus populated through the symmetric channel is also found to be lower than the asymmetric channel. Present investigation directly shows the effect of entrance channel mass asymmetry on the reaction dynamics.

  5. New lifetime measurements in the stable semimagic Sn isotopes using the Doppler-shift attenuation technique

    Precise measurements of lifetimes in the picosecond range of excited states in the stable even-A Sn isotopes 112,114,116,122Sn have been performed using the Doppler shift attenuation technique. For the first excited 2+ states in 112Sn, 114Sn and 116Sn the E2 transition strengths deduced from the measured lifetimes are in disagreement with the previously adopted values. They indicate a shallow minimum at N = 66 in contrast to the maximum at mid-shell predicted by modern shell model calculations.

  6. New lifetime measurements in the stable semimagic Sn isotopes using the Doppler-shift attenuation technique

    Jungclaus, A.; Walker, J.; Leske, J.; Speidel, K.-H.; Stuchbery, A. E.; East, M.; Boutachkov, P.; Cederkäll, J.; Doornenbal, P.; Egido, J. L.; Ekström, A.; Gerl, J.; Gernhäuser, R.; Goel, N.; Górska, M.; Kojouharov, I.; Maier-Komor, P.; Modamio, V.; Naqvi, F.; Pietralla, N.; Pietri, S.; Prokopowicz, W.; Schaffner, H.; Schwengner, R.; Wollersheim, H.-J.

    2011-09-01

    Precise measurements of lifetimes in the picosecond range of excited states in the stable even-A Sn isotopes 112,114,116,122Sn have been performed using the Doppler shift attenuation technique. For the first excited 2+ states in 112Sn, 114Sn and 116Sn the E2 transition strengths deduced from the measured lifetimes are in disagreement with the previously adopted values. They indicate a shallow minimum at N = 66 in contrast to the maximum at mid-shell predicted by modern shell model calculations.

  7. Evidence for reduced collectivity around the neutron mid-shell in the stable even-mass Sn isotopes from new lifetime measurements

    Precise measurements of the lifetimes of the first excited 2+ states in the stable even-A Sn isotopes 112-124Sn have been performed using the Doppler shift attenuation technique. For the isotopes 112Sn, 114Sn and 116Sn the E2 transition strengths deduced from the measured lifetimes are in disagreement with the previously reported values and indicate a shallow minimum at N=66. The observed deviation from a maximum at mid-shell is attributed to the obstructive effect of the s1/2 neutron orbital in generating collectivity when near the Fermi level.

  8. Resonant Continuum in the Relativistic Mean-Field Theory

    CAOLi-Gang; MAZhong-Yu

    2002-01-01

    Energies,widths and wave functions of the single-particle resonant continuum are determined by solving scattering states of the Dirac equation with proper asymptotic conditions for the continuous spectrum in the relativistic mean-field theory.The relativistic regular and irregular Coulomb wave functions are calculated numerically.The resonance states in the continum for some closed-or sub-closed-shell nucleus in Sn-isotopes,such as 114Sn,116Sn,118Sn,and 120Sn are calculated.Results show that the S-matrix method is a reliable and straightforward way in determining energies and widths of resonant states.

  9. Temperature antipairing effect over the energy weighted sum rule

    We study the temperature dependence of the sum rules using the discontinuity of the first derivative of the Matsubara Green's functions of a bilinear particle-hole operator. Particularly we study the behavior of the dipole particle-hole operator. We applied the calculation to 114Sn, 138Ba, 154Gd and 170Yb. It is found that the energy weighted sum rule for the dipole operator changes as a function of the temperature depending on the square of the gap. This fact is related to the antipairing effect of the temperature over the nuclear system

  10. Combinatorial Level Densities from a Microscopic Relativistic Structure Model

    Pezer, R.; Ventura, A.; Vretenar, D.

    2002-01-01

    A new model for calculating nuclear level densities is investigated. The single-nucleon spectra are calculated in a relativistic mean-field model with energy-dependent effective mass, which yields a realistic density of single-particle states at the Fermi energy. These microscopic single-nucleon states are used in a fast combinatorial algorithm for calculating the non-collective excitations of nuclei. The method, when applied to magic and semi-magic nuclei, such as $^{60}$Ni, $^{114}$Sn and $...

  11. Deperturbation of the 011 → 010 hot band for ZnH2 and ZnD2

    Motallebipour, Maryam S.; Shayesteh, Alireza

    2015-12-01

    Local perturbations observed in the 0111 (Πg) → 0110 (Πu) hot bands of 64ZnH2, 66ZnH2, 68ZnH2, 64ZnD2 and 66ZnD2 have been analyzed. The 0111 (Πg) state is perturbed by the nearby 040 vibrational level that contains 0440 (Γg), 0420 (Δg) and 0400 ( Σg+) states. Appropriate Hamiltonian matrices were constructed in which the effects of rotational ℓ -type doubling, ℓ -type resonance and Coriolis interaction were taken into account, and nonlinear least squares fits were performed. Unperturbed constants were obtained for the 0111 (Πg) states, along with vibrational energies of the 040 (perturbing) levels and the Coriolis interaction coefficients. Relative vibrational energies of the 040 and 030 levels were then used to estimate the origins of the bending mode fundamental bands, resulting in ν2 vibrational wavenumbers of 634.45 cm-1 and 459.14 cm-1, for 64ZnH2 and 64ZnD2, respectively.

  12. Isotopic fractionation of zinc in tektites

    Moynier, Frederic; Beck, Pierre; Jourdan, Fred; Yin, Qing-Zhu; Reimold, Uwe; Koeberl, Christian

    2009-01-01

    Tektites are terrestrial natural glasses produced during a hypervelocity impact of an extraterrestrial projectile onto the Earth's surface. The similarity between the chemical and isotopic compositions of tektites and terrestrial upper continental crust implies that the tektites formed by fusion of such target rock. Tektites are among the driest rocks on Earth. Although volatilization at high temperature may have caused this extreme dryness, the exact mechanism of the water loss and the behavior of other volatile species during tektite formation are still debated. Volatilization can fractionate isotopes, therefore, comparing the isotope composition of volatile elements in tektites with that of their source rocks may help to understand the physical conditions during tektite formation. For this study, we have measured the Zn isotopic composition of 20 tektites from four different strewn fields. Almost all samples are enriched in heavy isotopes of Zn compared to the upper continental crust. On average, the different groups of tektites are isotopically distinct (listed from the isotopically lightest to the heaviest): Muong-Nong type indochinites ( δ66/64Zn = 0.61 ± 0.30‰); North American bediasites ( δ66/64Zn = 1.61 ± 0.49‰); Ivory Coast tektites ( δ66/64Zn = 1.66 ± 0.18‰); the Australasian tektites (others than the Muong Nong-type indochinites) ( δ66/64Zn = 1.84 ± 0.42‰); and Central European moldavites ( δ66/64Zn = 2.04 ± 0.19‰). These results are contrasted with a narrow range of δ66/64Zn = 0-0.7‰ for a diverse spectrum of upper continental crust materials. The elemental abundance of Zn is negatively correlated with δ66/64Zn, which may reflect that isotopic fractionation occurred by evaporation during the heating event upon tektite formation. Simple Rayleigh distillation predicts isotopic fractionations much larger than what is actually observed, therefore, such a model cannot account for the observed Zn isotope fractionation in tektites. We

  13. ZZ FSXJ32, MCNP nuclear data library based on JENDL-3.2. ZZ FSXLIBJ33, MCNP nuclear data library based on JENDL-3.3

    1 - Description of program or function: - NEA-1424/03: JENDL-3.2 based MCNP library. Format: MCNP. Number of groups: Continuous energy cross section library. Nuclides: H, He, Li, Be, B, C, N, O, F, Na, Mg, Al, Si, P, S, Cl, Ar, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Ga, Ge, As, Se, Br, Kr, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Xe, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Hf, Ta, W, Pb, Bi, Ra, Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm. Temperatures: 293 K, 600 K, 900 K, 1200 K, 1500 K, 2000 K. Origin: JENDL-3.2. The temperature-dependent continuous energy cross section library for MCNP, FSXJ32, was prepared from JENDL-3.2 for a variety of applications in the field of atomic energy. - NEA-1424/06: April 2005: This is the DVD version of ZZ-FSXJ32 NEA-1424/03. - NEA-1424/07: This version differs from version NEA-1424/05 in the following: Index files xsdir.fsxlb331 and xsdir.fsxlb332 have been updated, since atomic weights were missing for 23 nuclides. JENDL-3.3 based MCNP library. Format: MCNP. Number of groups: Continuous energy cross section library. Nuclides: 337 nuclides contained in JENDL-3.3. H-1, H-2, He-3, He-4, Li-6, Li-7, Be-9, B-10, B-11, C-Nat, N-14, N-15, O-16, F-19, Na-23, Mg-24, Mg-25, Mg-26, Al-27, Si-28, Si-29, Si-30, P-31, S-32, S-33, S-34, S-36, Cl-35, Cl-37, Ar-40, K-39, K-40, K-41, Ca-40, Ca-42, Ca-43, Ca-44, Ca-46, Ca-48, Sc-45, Ti-46, Ti-47, Ti-48, Ti-49, Ti-50, V-Nat, Cr-50, Cr-52, Cr-53, Cr-54, Mn-55, Fe-54, Fe-56, Fe-57, Fe-58, Co-59, Ni-58, Ni-60, Ni-61, Ni-62, Ni-64, Cu-63, Cu-65, Ga-69, Ga-71, Ge-70, Ge-72, Ge-73, Ge-74, Ge-76, As-75, Se-74, Se-76, Se-77, Se-78, Se-79, Se-80, Se-82, Br-79, Br-81, Kr-78, Kr-80, Kr-82, Kr-83, Kr-84, Kr-85, Kr-86, Rb-85, Rb-87, Sr-86, Sr-87, Sr-88, Sr-89, Sr-90, Y-89, Y-91, Zr-90, Zr-91, Zr-92, Zr-93, Zr-94, Zr-95, Zr-96, Nb-93, Nb-94, Nb-95, Mo-92, Mo-94, Mo-95, Mo-96, Mo-97, Mo-98, Mo-99, Mo-100, Tc-99, Ru-96, Ru-98, Ru-99, Ru-100, Ru-101, Ru-102, Ru-103, Ru-104, Ru-106, Rh

  14. Asymptotic and near-target direct breakup of 6Li and 7Li

    Kalkal, Sunil; Simpson, E. C.; Luong, D. H.; Cook, K. J.; Dasgupta, M.; Hinde, D. J.; Carter, I. P.; Jeung, D. Y.; Mohanto, G.; Palshetkar, C. S.; Prasad, E.; Rafferty, D. C.; Simenel, C.; Vo-Phuoc, K.; Williams, E.; Gasques, L. R.; Gomes, P. R. S.; Linares, R.

    2016-04-01

    Background: Li,76 and 9Be are weakly bound against breakup into their cluster constituents. Breakup location is important for determining the role of breakup in above-barrier complete fusion suppression. Recent works have pointed out that experimental observables can be used to separate near-target and asymptotic breakup. Purpose: Our purpose is to distinguish near-target and asymptotic direct breakup of Li,76 in reactions with nuclei in different mass regions. Method: Charged particle coincidence measurements are carried out with pulsed Li,76 beams on 58Ni and 64Zn targets at sub-barrier energies and compared with previous measurements using 208Pb and 209Bi targets. A detector array providing a large angular coverage is used, along with time-of-flight information to give definitive particle identification of the direct breakup fragments. Results: In interactions of 6Li with 58Ni and 64Zn, direct breakup occurs only asymptotically far away from the target. However, in interactions with 208Pb and 209Bi, near-target breakup occurs in addition to asymptotic breakup. Direct breakup of 7Li into α -t is not observed in interactions with 58Ni and 64Zn. However, near-target dominated direct breakup was observed in measurements with 208Pb and 209Bi. A modified version of the Monte Carlo classical trajectory model code platypus, which explicitly takes into account lifetimes associated with unbound states, is used to simulate sub-barrier breakup reactions. Conclusions: Near-target breakup in interactions with Li,76 is an important mechanism only for the heavy targets 208Pb and 209Bi. There is insignificant near-target direct breakup of 6Li and no direct breakup of 7Li in reactions with 58Ni and 64Zn. Therefore, direct breakup is unlikely to suppress the above-barrier fusion cross section in reactions of Li,76 with 58Ni and 64Zn nuclei.

  15. Nuclear data measurements in 3x592 GBq 241Am-Be neutron cell

    . Cumulative fission yield for the fission products from 232Th(n, f) and 238U(n, f) reactions in a neutron spectrum of average 5.0 MeV energy, were measured. For 232Th(n, f) reaction, cumulative fission yield of 16 fission products between A = 87 - 143 was measured and for 238U(n, f) reaction, cumulative fission yield of 33 fission products between A = 87 - 146 was measured. Neutron threshold detectors are used for determining reactor radiation damage, neutron flux measurements and in neutron dosimeters. Cross section measurements were performed for the following threshold detectors in the given neutron energies: for 103Rh(n, n')103mRh at 4.83 MeV, for 115In(n, n')115mIn at 4.97 MeV, for 232Th(n, f) at 5.02 MeV, for 238U(n, f) at 5.04 MeV, for 47Ti(n, p)47Sc at 5.23 MeV, for 64Zn(n, p)64Cu at 5.45 MeV, for 58Ni(n, p)58Co at 5.45 MeV, for 54Fe(n, p)54Mn at 5.71 MeV, for 46Ti(n, p)46Sc at 6.16 MeV, for 27Al(n, p)27Mg at 6.47 MeV, for 56Fe(n, p)56Mn at 7.72 MeV, for 24Mg(n, p)24Na at 8.21 MeV, for 59Co(n, α)56Mn at 8.21 MeV, for 27Al(n, α)24Na at 8.43 MeV and for 48Ti(n, p)48Sc at 8.72 MeV. It is especially crucial to know accurately the gamma ray intensities of 234Th,234mPa and 234gPa nuclides, which are important for the evaluation of the dose balance of depleted uranium and the efficiency calibration of the high efficiency gamma detectors and are in secular equilibrium with 238U. Here, intensities (decay probabilities) of 72 gamma rays of 234mPa and 234gPa nuclides were measured. In 3 x 592 GBq Am-Be neutron irradiation cell, qualitative and quantitative detection limits were determined for Na, Al, Cl, K, Ti, V, Mn, Fe, Co, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Y, Mo, Ru, Ag, Cd, In, Sb, I, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Yb, Lu, Hf, W, Pt, Au, Th and U elements. By using the cyclic activation analysis method, half lives of 28Al, 52V, 66Cu, 77mSe, 86mRb, 108Ag, 110Ag, 122mSb, 161Gd, 165mDy and 179mHf radioisotopes, which were induced by 27Al(n, γ)28Al, 51V(n,

  16. Risk of overestimation of urinary cadmium concentrations: interference from molybdenum

    Cañas A.I.

    2013-04-01

    Full Text Available We show here that the selection of analytical method is critical when measuring low levels of cadmium in human urine. Cadmium is today usually analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS, which has a higher sensitivity than Atomic Absorption Spectroscopy (AAS. ICP-MS cadmium measurements show interference from tin (114Sn and molybdenum oxides, which can result in an overestimation of cadmium levels. The 114Sn interference is stable and can be mathematically corrected. Molybdenum concentrations in urine are variable and different from individual to individual. We have estimated the degree of error which molybdenum interference introduces in the measurement of cadmium in urine by conventional ICP-MS. 268 urine samples from mothers and their children were measured. Removal of the molybdenum oxide interference (DRC-ICP-MS method reduced urinary cadmium concentrations significantly (47.8%. The urinary molybdenum concentration in children was higher than in their mothers, resulting in greater overestimation. Our results clearly show that the DRC method is essential for reliable measurements of urinary cadmium concentrations, particularly in children. Furthermore, care should be taken when comparing Human Biomonitoring data for cadmium in urine and attention should be paid to which analytical method has been used (e.g. AAS and ICP-Ms, and especially if the measurements have been corrected for molybdenum interference.

  17. Evaluation of zinc, cadmium and lead isotope fractionation during smelting and refining

    To evaluate metallurgical processing as a source of Zn and Cd isotopic fractionation and to potentially trace their distribution in the environment, high-precision MC-ICP-MS Zn, Cd and Pb isotope ratio measurements were made for samples from the integrated Zn-Pb smelting and refining complex in Trail, B.C., Canada. Significant fractionation of Zn and Cd isotopes during processing of ZnS and PbS ore concentrates is demonstrated by the total variation in δ66/64Zn and δ114/110Cd values of 0.42 per mille and 1.04 per mille , respectively, among all smelter samples. No significant difference is observed between the isotopic compositions of the Zn ore concentrates (δ66/64Zn = 0.09 to 0.17 per mille ; δ114/110Cd = - 0.13 to 0.18 per mille ) and the roasting product, calcine (δ66/64Zn = 0.17 per mille ; δ114/110Cd = 0.05 per mille ), due to ∼ 100% recovery from roasting. The overall Zn recovery from metallurgical processing is ∼ 98%, thus the refined Zn metal (δ66/64Zn = 0.22 per mille ) is not significantly fractionated relative to the starting materials despite significantly fractionated fume (δ66/64Zn = 0.43 per mille ) and effluent (δ66/64Zn = 0.41 to 0.51 per mille ). Calculated Cd recovery from metallurgical processing is 72-92%, with the majority of the unrecovered Cd lost during Pb operations (δ114/110Cd = - 0.38 per mille ). The refined Cd metal is heavy (δ114/110Cd = 0.39 to 0.52 per mille ) relative to the starting materials. In addition, significant fractionation of Cd isotopes is evidenced by the relatively light and heavy isotopic compositions of the fume (δ114/110Cd = - 0.52 per mille ) and effluent (δ114/110Cd = 0.31 to 0.46 per mille ). In contrast to Zn and Cd, Pb isotopes are homogenized by mixing during processing. The total variation observed in the Pb isotopic compositions of smelter samples is attributed to mixing of ore sources with different radiogenic signatures.

  18. Production of low and high specific activity 64Cu in a reactor

    Production of Copper-64 (64Cu) by irradiating copper and zinc metals in a reactor was evaluated. Low specific activity 64Cu can be easily produced using thermal neutrons via 63Cu (n,γ) 64Cu reaction, while use of fast neutrons are mandatory for high specific activity 64Cu via 64Zn (n,p) 64Cu reaction. Natural copper and zinc targets were irradiated in Pakistan Research Reactor-1. Radionuclidic impurities produced by thermal and fast neutrons were determined. Commonly available organic anion exchange resin (AG 1-X8) was used for the separation of no-carrier-added radiocopper from neutron irradiated zinc. More than 95% 64,67Cu was recovered. The radionuclidic and chemical purity of 64Cu was determined. The specific activity of 64Cu produced by 63Cu (n,γ) and 64Zn (n,p) was compared. (author)

  19. Continuum effects in the scattering of exotic nuclei

    Druet, T. [Universite Libre de Bruxelles (ULB), Physique Quantique, C.P. 165/82, Brussels (Belgium); Universite Libre de Bruxelles (ULB), Physique Nucleaire Theorique et Physique Mathematique, Brussels (Belgium); Descouvemont, P. [Universite Libre de Bruxelles (ULB), Physique Nucleaire Theorique et Physique Mathematique, Brussels (Belgium)

    2012-10-15

    We discuss continuum effects in the scattering of exotic nuclei, and more specifically on the {sup 11}Be + {sup 64}Zn scattering. {sup 11}Be is a typical example of an exotic nucleus, with a low binding energy. Elastic, inelastic and breakup cross-sections of the {sup 11}Be + {sup 64}Zn system are computed in the Continuum Discretized Coupled Channel formalism, at energies near the Coulomb barrier. We show that converged cross-sections need high angular momenta as well as as large excitation energies in the wave functions of the projectile. Extensions to other systems are simulated by different collision energies, and by varying the binding energy of {sup 11}Be. (orig.)

  20. Final results of an experiment to search for 2beta processes in zinc and tungsten with the help of radiopure ZnWO4 crystal scintillators

    Belli, P; Cappella, F; Cerulli, R; Danevich, F A; d'Angelo, S; Incicchitti, A; Kobychev, V V; Poda, D V; Tretyak, V I

    2011-01-01

    A search for the double beta decay of zinc and tungsten isotopes has been performed with the help of radiopure ZnWO4 crystal scintillators (0.1-0.7 kg) at the Gran Sasso National Laboratories of the INFN. The total exposure of the low background measurements is 0.529 kg yr. New improved half-life limits on the double beta decay modes of 64Zn, 70Zn, 180W, and 186W have been established at the level of 10^{18}-10^{21} yr. In particular, limits on double electron capture and electron capture with positron emission in 64Zn have been set: T_{1/2}(2\

  1. Study on bioavailability of zinc for children's diet by using activable isotopic tracer 70Zn and neutron activation analysis techniques

    Bioavailability of zinc for three groups (low amount of diet zinc, balance amount of diet zinc and high amount of diet zinc) of children's diet is studied by using activable isotopic tracer 70Zn and neutron activation analysis techniques. The results indicate that the fractional absorption of zinc from balance diet zinc group is the highest, up to 33.9%. A procedure of pre-irradiation concentration zinc for fecal samples using anion exchanger is developed, and the enriched 70Zn with isotopic abundance of 18.3% is used for tracer. The mass ratios between 70Zn and 68Zn or 64Zn and their contents between natural zinc and enriched zinc are used to calculate the bioavailability of zinc. Instrumental neutron activation analysis of 64Zn of each original fecal samples and pre-irradiation concentrated zinc samples are used to normalize the chemical yield in order to reduce the uncertainty during the chemical separation procedure

  2. Production and separation of 64Cu and 67Cu using 14 MeV neutrons

    64Cu and 67Cu were produced from 14 MeV neutron irradiated natural ZnO and enriched 64ZnO targets via 64Zn(n,p)64Cu and 67Zn(n,p)67Cu reactions. The ZnO disc targets were irradiated for 6 hours by 14 MeV neutrons, which are generated by bombarding a tritiated titanium target with deuteron beam at the Fusion Neutronics Source (FNS) at Japan Atomic Energy Agency (JAEA). After irradiation, ion chromatographic separations were carried out to obtain purified no-carrier-added Cu radionuclides. Elution pattern clearly showed separation of 64Cu and 67Cu giving a yield of > 90%, and a very low radionuclide impurity ratio of 65Zn within the purified 64Cu. (author)

  3. Zinc isotope fractionation on benzo-15-crown-5 resin by liquid chromatography

    Chromatographic fractionation of zinc isotopes was performed on the synthesized benzo-15-crown-5 resin as a column packing material at 323 K in the breakthrough manner for both a frontal and a rear bands. Zinc adsorption capacity was affected by anion chloride concentration and solvent dielectric constant. The heavier zinc isotopes were found enriched to the solution phase and the lighter zinc isotope was concentrated on the resin phase. The frontal maximum enrichment ratio for isotopic pair of 68Zn/64Zn was 1.0081. The isotope separation coefficients for isotopic pair of 68Zn/64Zn for frontal and rear band, were 5.3x10-4, 4.5x10-4, respectively. (author)

  4. Variation of the Concentration of Isotopes Copper and Zinc in Human Plasmas of Patients Affected by Cancer

    Triassi, Antonio

    2006-02-01

    In this paper, we demonstrate that the increase of copper and the reduction of zinc in the human plasma of patient with cancer, and in particular the Lymphoid Leukaemia, is a consequence of the isotopic constant of the enzymatic components copper/zinc dependent (DNA/RNA polymerase). Our hypothesis is that the reaction happens at the nuclear level in the human cell, and it is due to the action of a neutron (probably of deuterium of water) (J.F. Thomson, Biological Effects of Deuterium, Pergamon Press, Oxford, 1963) with the isotopic component of 64Zn transmutation into 65Cu stable following reaction: [ ^{64}Zn + N(HDO) rightarrow ^{65}Zn rightarrow beta^+ rightarrow EC rightarrow gamma rightarrow ^{65}Cu ] this produces energy of 0.325 MeV for the β+ and equal energy of 1.118 MeV for the photon γ with a half-life of 250 days.

  5. Properties of rotational bands at the spin limit in A {approximately} 50, A {approximately} 65 and A {approximately} 110 nuclei

    Janzen, V.P.; Andrews, H.R.; Ball, G.C. [Chalk River Labs., Ontario (Canada)] [and others

    1996-12-31

    There is now widespread evidence for the smooth termination of rotational bands in A {approx_equal} 110 nuclei at spins of 40-to-50{Dirac_h}s. The characteristics of these bands are compared to those of bands recently observed to high spin in {sup 64}Zn and {sup 48}Cr, studied with the 8{pi} {gamma}-ray spectrometer coupled to the Chalk River miniball charged-particle-detector array.

  6. Thermal properties of a rotating nucleus in a fluctuating mean field approach

    B K Agrawal; Ansari, A

    1993-01-01

    The static path approximation to the path integral representation of partition function provides a natural microscopic basis to deal with thermal fluctuations around mean field configurations. Using this approach for one-dimensional cranking Hamiltonian with quadrupole- quadrupole interaction term we have studied a few properties like energy, level density, level density parameter($a$) and moment of inertia as a function of temperature and spin for $^{64}Zn$ taking it as an illustrative examp...

  7. Investigation of the fast neutron induced (n, α) reaction. (Experimental techniques)

    For investigation of the fast neutron induced (n, α)-reaction, two grid-type gas-filled twin ionization chambers were developed and tested. Using the ionization chambers, the energy spectra, angular distributions and cross sections of the (n, α)-reaction were measured around En=5 MeV for 40Ca, 58Ni and 64Zn. 27 refs., 20 figs., 1 tab

  8. Search for entrance channel effects in fusion reactions via neutron evaporation

    It is generally expected that the compound nuclei formed at the given excitation energies and the angular momenta follow a statistical decay pattern independent of a particular reaction that led to fusion. In order to search the entrance channel effects in the decay of compound nucleus, the reaction 16O + 64Zn at oxygen beam energy of 91 MeV and 95 MeV are investigated

  9. Study of entrance channel effects in the decay of compound nucleus

    In order to study the entrance channel effects in the decay of compound nucleus the neutron spectra at different laboratory angles were measured from the fusion reaction 16O+63Cu at 109 MeV and 16O+64Zn at 91MeV. The results are compared with the symmetric system 32S+48Ti at 120 and 125 MeV

  10. Determination of activable isotopic tracers of zinc by neutron activation analysis for study of bioavailability of zinc

    A procedure of pre-irradiation concentration of zinc in fecal samples using anion exchanger was developed for the study of the bioavailability of zinc by neutron activation analysis. The mass ratios between 70Zn and 68Zn, or 64Zn and their contents between natural zinc and enriched zinc are used to calculate the bioavailability of zinc when the abundance of the isotope 70Zn is not high enough. (author) 9 refs.; 1 fig.; 2 tabs

  11. Mediating conducting polymer growth within hydrogels by controlling nucleation

    A. J. Patton; Green, R A; L. A. Poole-Warren

    2015-01-01

    This study examines the efficacy of primary and secondary nucleation for electrochemical polymerisation of conductive polymers within poly(vinyl alcohol) methacrylate hydrogels. The two methods of nucleation investigated were a primary heterogeneous mechanism via introduction of conductive bulk metallic glass (Mg64Zn30Ca5Na1) particles and a secondary mechanism via introduction of “pre-polymerised” conducting polymer within the hydrogel (PEDOT:PSS). Evidence of nucleation was not seen in the ...

  12. Enrichment of zinc isotopes by a liquid membrane system using a crown ether

    A liquid membrane system to enrich zinc isotope was investigated. The liquid membrane was composed of a solution of dicyclohexano-18-crown-6 in chloroform. Zinc chloride dissolved in diluted hydrochloric acid was used as a feed phase. A receiving phase was made of a 0.001 M HCl solution. The zinc isotopes were enriched (1) at the interface of the liquid-membrane/feed-phase and (2) at that of the liquid-membrane/receiving-phase. The separation factor attained in the system was α = 1.049 for the separation of 64Zn and 66Zn. The enrichment factor of 66Zn relative to 67Zn was ε = -0.053, which is in the inverse direction of enrichment by a liquid-liquid extraction. The enrichment factor of 64Zn to 66Zn showed a different value from that of 66Zn to 68Zn, regardless of their similar mass difference. The isotope effects in the Zn-crown complex were dominated by the field shift of electronic energy in the isotope atom. This is in contrast to the Bigeleisen-Mayer approximation for a chemical exchange reaction. Trace amounts of zinc are injected into the primary coolant of boiling water reactors in order to suppress 60Co build-up. The use of 64Zn-depleted zinc suppresses the production of 65Zn within the reactor. Zinc isotopes are also useful precursors of radiopharmaceuticals

  13. Isotope separation of zinc by ion cyclotron resonance

    The separation of zinc isotopes has been performed in CEA Saclay by ion cyclotron resonance (ICR). Zinc, enriched in the isotope 68 is needed for medical applications and zinc, depleted in the isotope 64, in nuclear water reactors. A high density (up to 8 x 1011 cm-3), low electronic temperature (1-3 eV) plasma has been obtained, using Joule heating combined with electron cyclotron resonance heating. The density and electronic radial profiles have been measured as well as the multicharged ions, which have been found negligible. The selective resonant heating of 68 Zn, measured with an electrostatic analyser, has reached 180 eV, while the ionic energy of non resonant isotopes remains around 3 eV. In the so-called depletion experiments, we choose to have 64 Zn resonant; in this case, the 64 Zn ion energy was increased up to 150 eV. The conditions for depleting the initial natural zinc in 64 Zn have been optimised: i.e. the rich collector bias and the spacing of the blades of the 'rich'collector. It has been easy to get a depletion factor of 0.26 with a high flow rate. As a conclusion, operating conditions that make the ICR process attractive in the depletion mode have been derived. (author)

  14. Zinc isotope effects observed by liquid chromatography with benzo-15-crown-5 resin

    The chromatographic fractionation in Zn isotopes was performed on the synthesized benzo-15-crown-5 resin at 313 and 343 K. The lighter isotopes were found enriched in the resin phase. The isotope fractionation coefficients (ε) were 3.4 and 2.9x10-4, 4.7 and 4.7x10-4, and 6.7 and 5.7x10-4 for the 66Zn/64Zn, 67Zn/64Zn and 68Zn/64Zn isotopic pairs at 313 and 343 K, respectively. They reflected mass-dependence among the Zn isotopes at each operated temperature but did not show 1/T2-temperature proportionality. The temperature effects of the composition of Zn species both in the solution phase and in the resin phase may account in part for the latter observation. The magnitudes of ε's in this study were comparable to the ones obtained by ion exchange chromatography, but much smaller than those observed in the solvent extraction systems with a crown ether in the organic phase. (author)

  15. Intermediate-energy Coulomb excitation of 104Sn: Moderate E2 strength decrease approaching 100Sn

    Doornenbal, P; Aoi, N; Matsushita, M; Obertelli, A; Steppenbeck, D; Wang, H; Audirac, L; Baba, H; Bednarczyk, P; Boissinot, S; Ciemala, M; Corsi, A; Furumoto, T; Isobe, T; Jungclaus, A; Lapoux, V; Lee, J; Matsui, K; Motobayashi, T; Nishimura, D; Ota, S; Pollacco, E C; Sakurai, H; Santamaria, C; Shiga, Y; Sohler, D; Taniuchi, R

    2013-01-01

    The reduced transition probability B(E2) of the first excited 2+ state in the nucleus 104Sn was measured via Coulomb excitation in inverse kinematics at intermediate energies. A value of 0.163(26) e^2b^2 was extracted from the absolute cross-section on a Pb target, while the method itself was verified with the stable 112Sn isotope. Our result deviates significantly from the earlier reported value of 0.10(4) e^2b^2 and corresponds to a moderate decrease of excitation strength relative to the almost constant values observed in the proton-rich, even-A 106-114Sn isotopes. Present state-of-the-art shell-model predictions, which include proton and neutron excitations across the N=Z=50 shell closures as well as standard polarization charges, underestimate the experimental findings

  16. Study of the giant dipole resonance built on highly excited states in Sn and Dy nuclei

    A study is presented of the giant dipole resonance built on highly excited states. The aim is to get more detailed information on the properties of the GDR and to use it as a tool for the investigation of nuclear structure at high excitation energy. The high energy γ-rays seen from the decay of excited state GDRs in heavy ion fusion reactions reflect the average properties of the states populated by the γ-emission. The measurements at different initial excitation energies of 114Sn provide information on the nuclear level density near the particle separation energy at an average angular momentum of 10ℎ. The study of shape changes at very high spin in 152-156Dy nuclei is presented. A theoretical model developed to describe fusion-evaporation reactions is presented. 149 refs.; 63 figs.; 13 tabs

  17. Pre-compound neutron evaporation in heavy ion fusion reactions

    In the present investigation, exclusive neutron spectra have been measured in coincidence with the observed γ-rays characteristic to the residual nuclei 53Fe, 55Fe and 56Co. In this new experimental study, we have followed the strategy of forming the compound nucleus 58Ni at the same excitation energy through two different entrance channels viz the mass symmetric reaction 31P +27Al and the mass asymmetric reaction 12C + 46Ti

  18. High-Spin States in Odd-Odd N=Z {sup 46}V

    O' Leary, C.D.; Bentley, M.A.; Appelbe, D.E.; Bark, R.A.; Cullen, D.M.; Erturk, S.; Maj. A.; Sheikh, J.A.; Warner, D.D.

    1999-12-31

    High-spin states up to the F{sub 7/2}-shell band termination at J{pi}=15+ have been observed for the first time in the odd-odd N=Z=23 nucleous {sup 46}V. The new level scheme has two separate structures corresponding to spherical and prolate shapes. A rotational band has very similar energies to the yrast sequence in {sup 46}Ti and is therefore assumed to be a T=1 configuration.

  19. INFLUENCE OF AGEING ON THE INTERNAL FRICTION OF Nb-Ti-N ALLOYS

    Heulin, B.; Clauss, A.

    1981-01-01

    We have studied the influence of ageing on the internal friction of various Nb-4.6Ti-N alloys at 1Hz, annealed for 24 hours at 400, 600, and 800°C. This study shows the influence of temperature, beginning at 400°C, on the measurements of internal friction and allows a more complete description of the structure and behaviour of Nb-Ti-N alloys.

  20. Search for the Jacobi shape transition in light nuclei

    The γ-rays following the reaction 105 MeV 18O+28Si have been measured using the EUROBALL IV, HECTOR and EUCLIDES arrays in order to investigate the predicted Jacobi shape transition. The high-energy γ-ray spectrum from the GDR decay indicates the presence of large deformations in the hot 46Ti nucleus, in agreement with new theoretical calculations based on the rotating liquid-drop model. (orig.)

  1. Search for the Jacobi shape transition in light nuclei

    Maj, A; Brekiesz, M; Grebosz, J; Meczynski, W; Styczen, J; Zieblinski, M; Zuber, K; Bracco, A; Camera, F; Benzoni, G; Million, B; Blasi, N; Brambilla, S; Leoni, S; Pignanelli, M; Wieland, O; Nyberg, J; Kicinska-Habior, M; Petrache, C M; Dudek, J; Pomorski, K

    2003-01-01

    The gamma-rays following the reaction 105 MeV 18O + 28Si have been measured using the EUROBALL IV, HECTOR and EUCLIDES arrays in order to investigate the predicted Jacobi shape transition. The high-energy gamma-ray spectrum from the GDR decay indicates a presence of large deformations in hot 46Ti nucleus, in agreement with new theoretical calculations based on the Rotating Liquid Drop model.

  2. Search for the Jacobi shape transition in light nuclei

    Maj, A.; Kmiecik, M.; Brekiesz, M.; Grebosz, J.; Meczynski, W.; Styczen, J.; Zieblinski, M.; Zuber, K. [The Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, PL-31342, Krakow (Poland); Bracco, A.; Camera, F.; Benzoni, G.; Million, B.; Blasi, N.; Brambilla, S.; Leoni, S.; Pignanelli, M.; Wieland, O. [Dipartimento di Fisica and INFN sez. Milano, I-20133, Milano (Italy); Herskind, B. [The Niels Bohr Insitute, Blegdamsvej 17, DK-2100, Copenhagen (Denmark); Bednarczyk, P. [The Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, PL-31342, Krakow (Poland); Institut de Recherches Subatomiques, 23 rue du Loess, BP28, F-67037, Strasbourg (France); Curien, D. [Institut de Recherches Subatomiques, 23 rue du Loess, BP28, F-67037, Strasbourg (France); Vivien, J.P.; Farnea, E.; De Angelis, G.; Napoli, D.R.; Nyberg, J.; Kicinska-Habior, M.; Petrache, C.M.; Dudek, J.; Pomorski, K.

    2004-04-01

    The {gamma}-rays following the reaction 105 MeV {sup 18}O+{sup 28}Si have been measured using the EUROBALL IV, HECTOR and EUCLIDES arrays in order to investigate the predicted Jacobi shape transition. The high-energy {gamma}-ray spectrum from the GDR decay indicates the presence of large deformations in the hot {sup 46}Ti nucleus, in agreement with new theoretical calculations based on the rotating liquid-drop model. (orig.)

  3. Serpentinization at Isua, a forearc environment identified by Zn isotopes

    Pons, M.; Quitté, G.; Rosing, M.; Douchet, C.; Reynard, B.; Mills, R.; Albarede, F.

    2010-12-01

    The present study deals with the isotope compositions of Zn in the 3.8 Ga old serpentinites from the Archean complex of Isua, Greenland. The sample set includes igneous, metamorphic, and sedimentary rocks such as serpentinites, metagabbros, amphibolites, talc schists, and metagreywackes. For comparison, modern serpentines from Mexico and the Alps were also analyzed together with deep-sea clays from the Pacific, and metalliferous sediments from the East Pacific Rise and from the TAG area. The modern serpentinites show the enrichment in heavy zinc, with δ66/64Zn values from +0.21 to +0.52‰, typical of the modern igneous rocks. In contrast, the δ66/64Zn values of the Isua serpentines are conspicuously negative and range from -0.48 ‰ to +0.04 ‰ and can be clearly distinguished from other both igneous and sedimentary lithologies from the same area, in which the δ66/64Zn values range from -0.08 to 0.36‰ and overlap with the range of modern igneous rocks. Along mid-oceanic ridges, serpentinization takes place in high-temperature hydrothermal fields (typically > 250°C). The modern serpentinites analyzed seem to have formed in that way and formed by interaction between peridotites and low-pH, high-temperature, high-salinity seawater. Under such conditions, zinc is leached from rock by hydrothermal fluids as Zn2+ [1]. During this reaction, Zn from the rocks becomes depleted in light isotopes and its δ66/64Zn rises. The higher the temperature of the fluid, the lighter its isotope Zn composition becomes [2]. The remarkably low δ66/64Zn observed in Isua serpentinites indicates a different context of alteration and suggests reaction of peridotites with a low-temperature and high-pH fluid, which stabilizes Zn-sulfide complexes in solution. This is consistent with the arc subduction zone model of Isua [3]. Our δ66/64Zn data suggest that the closest equivalents of Isua serpentinites are the serpentinite mud volcanoes from the Mariana forearc [4]. This arc is

  4. Theoretical and experimental cross sections for neutron reactions on 64Zinc

    Accurate measurements of the 64Zn (n,2n) 64Cu and 64Zn (n,p) 63Zn cross sections at 14.8 MeV have been made using a Texas Nuclear Neutron Generator and the activation technique. A NaI(T1) spectrometer (using two 6'' x 6'' NaI detectors/crystals) was used to measure the gamma radiation emitted in coincidence from the positron-emitting decay products. The measurements were made relative to 65Cu (n,2n) /64/Cu and 63Cu (n,2n) 62Cu cross sections, which have similar half-lives, radiation emission, and were previously measured to high accuracy (2 percent). The value obtained for the (n,2n) measurement was 199 /+-/ 6 millibarns, and a value of 176 /+-/ 4.5 millibarns was obtained for the (n,p) measurement. In concert, a theoretical analysis of neutron induced reactions on /64/Zn was performed at Los Alamos National Laboratory using the Hauser-Feshbach statistical theory in the GNASH code over an energy range of 100 keV to 20 MeV. Calculations included width fluctuation corrections, direct reaction contributions, and preequilibrium corrections above 6 MeV. Neutron optical model potentials were determined for zinc. The theoretical values agree with the new 14.8 MeV measurements approximately within experimental error, with calculations of 201 millibarns for the (n,2n) cross section and 170 millibarns for the (n,p) cross section. Results from the analysis will be made available in National Evaluated Nuclear Data Format (ENDF/B) for fusion energy applications. 50 refs., 34 figs., 10 tabs

  5. Structure of high-spin states in A {approx} 60 region

    Nakada, Hitoshi [Chiba Univ. (Japan); Furutaka, K.; Hatsukawa, Y. [and others

    1998-03-01

    High-spin states in the proton-rich Cu-Zn nuclei are investigated by the experiments at JAERI. New levels and {gamma}-rays are identified by the particle-{gamma}-{gamma} coincidence, and J{sup P} assignments are made via the DCO ratio analysis. Yrast sequences are observed up to J {approx} 18 for {sup 62}Zn, and {sup 64}Zn, J {approx} 27/2 for {sup 61}Cu and J {approx} 23/2 for {sup 63}Cu. Though we cannot settle new J{sup P} values for {sup 61,63}Zn, their yrast sequence is also extended. In {sup 64}Zn, a doublet of {gamma}-rays is discovered at 1315 keV, clarifying the similarity in the level scheme between {sup 62}Zn and {sup 64}Zn. We reproduce the yrast levels by a shell-model calculation, by which structure of the high-spin states is further studied. A parity change in the yrast sequence is established, in which the unique-parity orbit 0g{sub 9/2} plays an essential role; one nucleon excitation to g{sub 9/2} gains high angular momentum with low seniority, at the cost of the single-parity energy. Second parity-change is also suggested by the calculation. Such parity change seems characteristic to spherical or nearly spherical nuclei. In {sup 61}Cu, concentration of the {gamma}-ray intensity is observed. This happens because a stretched 3-quasiparticle configuration including 0g{sub 9/2} is relatively stable, similarly to some isomers. Thus, by studying the structure of the high-spin states of the A {approx} 60 nuclei, we have clarified the role of unique-parity orbit in high-spin states, which may be generic to spherical and nearly spherical nuclei. (J.P.N.)

  6. Theoretical and experimental cross sections for neutron reactions on /sup 64/Zinc

    Rutherford, D.A.

    1988-03-01

    Accurate measurements of the /sup 64/Zn (n,2n)/sup 63/Zn and /sup 64/Zn (n,p)/sup 64/Cu cross sections at 14.8 MeV have been made using a Texas Nuclear Neutron Generator and the activation technique. A NaI(Tl) spectrometer (using two 6'' x 6'' NaI detectors/crystals) was ued to measure the gamma radiation emitted in coincidence from the positron-emitting decay products. The measurements were made relative to /sup 65/Cu (n,2n)/sup 64/Cu and /sup 63/Cu (n,2n)/sup 62/Cu cross sections, which have similar half-lives, radiation emission, and were previously measured to high accuracy (2%). The value obtained for the (n,2n) measurement was 199 +- 6 millibarns, and a value of 176 +- 4.5 millibarns was obtained for the (n,p) measurement. In concert, a theoretical analysis of neutron induced reactions on /sup 64/Zn was performed at Los Alamos National Laboratory using the Hauser-Feshbach statistical theory in the GNASH code over an energy range of 100 keV to 20 MeV. Calculations included width fluctuation corrections, direct reaction contributions, and preequilibrium corrections above 6 MeV. Neutron optical model potentials were determined for zinc. The theoretical values agree with the new 14.8 MeV measurements approximately within experimental error, with calculations of 201 millibarns for the (n,2n) cross section and 170 millibarns for the (n,p) cross section. Results from the analysis will be made available in National Evaluated Nuclear Data Format (ENDF/B) for fusion energy applications. 50 refs., 34 figs., 10 tabs.

  7. Elastic and break-up of the 1n-halo 11Be nucleus

    Di Pietro, A.; Moro, A. M.; Acosta, L.; Amorini, F.; Borge, M. J. G.; Figuera, P.; Fisichella, M.; Fraile, L. M.; Gomez-Camacho, J.; Jeppesen, H.; Lattuada, M.; Martel, I.; Milin, M.; Musumarra, A.; Papa, M.; Pellegriti, M. G.; Perez-Bernal, F.; Raabe, R.; Randisi, G.; Rizzo, F.; Scuderi, V.; Tengblad, O.; Torresi, D.; Vidal, A. Maira; Voulot, D.; Wenander, F.; Zadro, M.

    2014-03-01

    The elastic and break-up angular distributions of the 10,11Be+64Zn reactions measured at Ec.m.≈1.4 VC have been analysed within the CCDC and O.M. frameworks. The suppression of the Coulomb-nuclear interference, observed in the 11Be scattering case with respect to the 10Be, has been interpreted as due to a long range absorption owing to the coupling with the break-up (Coulomb and nuclear) channels. The presence of 10Be events on the 11Be experiment data have been explained as due mainly to break-up processes.

  8. Elastic and break-up of the 1n-halo 11Be nucleus

    Di Pietro A.

    2014-03-01

    Full Text Available The elastic and break-up angular distributions of the 10,11Be+64Zn reactions measured at Ec.m.≈1.4 VC have been analysed within the CCDC and O.M. frameworks. The suppression of the Coulomb-nuclear interference, observed in the 11Be scattering case with respect to the 10Be, has been interpreted as due to a long range absorption owing to the coupling with the break-up (Coulomb and nuclear channels. The presence of 10Be events on the 11Be experiment data have been explained as due mainly to break-up processes.

  9. Study of the 16O+64,66,68Zn reactions

    Excitation functions for the fusion of 16O with 64,66Zn in the energy range of 0.8-1.7 times the Coulomb barrier were measured. Reduced fusion excitation functions, scaled to remove the geometrical effects shown and isotopic effect in the excitation functions for the sub-barrier energies. Furthermore, angular distributions for the elastic scattering were measured for the 16O+64,68Zn systems in the energy range from 43 MeV to 56 MeV for the 16O. An anomalous back-angle elastic scattering was observed for the 16O+64Zn system and for energies around the Coulomb barrier. (Author)

  10. Gridded ionization chamber and dual parameter measurement system for fast neutron-induced charged particles emission reaction

    A twin ionization chamber with a common cathode and grids is described for (n,α), (n,p) studies. The chamber is used to determine the energy spectra and angular distribution of the charged particles emitted from the sample positioned on the cathode by dual parameter measurements of coinciding pulses from the anode and cathode of the ionization chamber. Pu α source is used to test the property of the chamber, an isotropic angular distribution is basically showed and the energy resolution is about 2%. This ionization chamber has already been applied to the studies of the 40Ca(n,α) and 64Zn(n,α) reactions

  11. Cluster Model For Reactions Induced By Weakly Bound And/Or Exotic Halo Nuclei With Medium-Mass Targets

    Beck, C; Papka, P; Courtin, S; Rousseau, M; Souza, F A; Carlin, N; Neto, F Liguori; De Moura, M M; Del Santo, M G; Suade, A A I; Munhoz, M G; Szanto, E M; De Toledo, A Szanto; Keeley, N; Diaz-Torres, A; Hagino, K

    2010-01-01

    An experimental overview of reactions induced by the stable, but weakly-bound nuclei 6Li, 7Li and 9Be, and by the exotic, halo nuclei 6He, 8He, 8B, and 11Be on medium-mass targets, such as 58Ni, 59Co or 64Zn, is presented. Existing data on elastic scattering, total reaction cross sections, fusion processes, breakup and transfer channels are discussed in the framework of a CDCC approach taking into account the breakup degree of freedom.

  12. Dominance of binary dissipative reactions in nearly symmetric nucleus-nucleus collisions above 35 MeV/U

    Incomplete fusion or massive transfer mechanisms were invoked to explain the observed distributions of products, especially for heavy residues, for the nearly symmetric systems, 36Ar on 27Al from 55 to 95 MeV/u, and 64Zn on natTi, from 35 to 79 MeV/u. Charged products were detected in a nearly 4π geometry using two complementary multidetector systems. Lorentz invariant cross section maps plotted for different products show three sources for Z=1 and 2 particles: quasi-projectile, quasi-target and a third source, located at mid-rapidity. For heavier fragments, the mid-rapidity contribution vanishes. (K.A.)

  13. Probing dynamics of fusion reactions through cross-section and spin distribution measurement

    Kaur Maninder

    2016-01-01

    Full Text Available Present work aims to explicate the effect of entrance channel mass asymmetry on fusion dynamics for the Compound Nucleus 80Sr populated through two different channels, 16O+64Zn and 32S+48Ti, using cross-section and spin distribution measurements as probes. The evaporation spectra studies for these systems, reported earlier indicate the presence of dynamical effects for mass symmetric 32S+48Ti system.The CCDEF and TDHF calculations have been performed for both the systems and an attempt has been made to explain the reported deviations in the α-particle spectrum for the mass symmetric system.

  14. Enhanced production possibility of the therapeutic radionuclides 64Cu, 67Cu and 89Sr via (n,p) reactions induced by fast spectral neutrons

    Spahn, I.; Coenen, H. H.; Qaim, S. M.

    2004-01-01

    Spectrum averaged cross sections for the Zn-64(n, p)Cu-64, Zn-67(n, p)Cu-67 and Y-89(n, p)Sr-89 reactions were measured using a 14 MeV d(Be) neutron source. In each case a clean radiochemical separation was performed and the radioactivity of the product was determined via high-resolution gamma-ray spectrometry or anticoincidence beta(-) counting. The cross sections are three to five times higher than with a fission neutron spectrum. It is postulated that at an intense fast spectral neutron so...

  15. Study of the 16O+64,66,68Zn reactions: fusion and elastic scattering

    Excitation functions for the fusion of 16O with64,66Zn in the energy range of 0,8-1,7 times the coulomb barrier were measured. Reduced fusion excitation functions, scaled to remove the geometrical effects show an isotopic effect in the excitation functions for sub-barrier energies. Furthermore, angular distributions for the elastic scattering were measured for the 16O+ 64,68Zn systems in the energy range of 43 Mev to 56 Mev. An anomalous back-angle elastic scattering was observed for the 16O64Zn system for energies around the coulomb barrier. (author)

  16. Improvements on the present theoretical understanding of octupole correlations

    Some intriguing results, obtained in a recent survey of octupole properties for all even-even nuclei, are reanalyzed in order to understand the origin of the strong disagreement with experimental data and/or the strange behaviours observed. The limitations of the rotational formula to describe E1 and E3 transition strengths are discussed as well as the role played by octupole-quadrupole coupling in some specific nuclei such as 20Ne, 64Zn, 158Gd, 208Pb and 224Ra

  17. Fusion and neutron transfer reactions with weakly bound nuclei within time-dependent and coupled channel approaches

    Samarin, V. V.

    2016-05-01

    The time-dependent Schrödinger equation and the coupled channel approach based on the method of perturbed stationary two-center states are used to describe nucleon transfers and fusion in low-energy nuclear reactions. Results of the cross sections calculation for the formation of the 198Au and fusion in the 6He+197Au reaction and for the formation of the 65Zn in 6He+64Zn reaction agree satisfactorily with the experimental data near the barrier. The Feynman's continual integrals calculations for a few-body systems were used for the proposal of the new form of the shell model mean field for helium isotopes.

  18. Isotope effects of zinc in crown ether chromatography

    Isotope separation of zinc has been studied with a polymer-supported crown ether resin packed in glass columns. Chromatography was performed in a break-through manner by feeding a zinc chloride solution into the columns. The mass analysis revealed that the heavier isotope was enriched at the front part of the zinc adsorption band. This result means that the heavier isotopes are preferentially fractionated into the solution phase. The largest single-stage separation coefficient (ε) in the present work is 1.0 x 10-3 for the isotopic pair of 64Zn and 66Zn at 35degC. (author)

  19. Double beta decay of ^{64,70}Zn and ^{180,186}W isotopes

    Poda, D V

    2011-01-01

    The results of the experimental investigations of double beta processes in Zinc and Tungsten isotopes with the help of middle volume (117 g, 168 g and 699 g) low-background ZnWO_4 crystal scintillators are presented. The experiment was carried out in the low-background "DAMA/R&D" set-up at the Gran Sasso National Laboratories of the INFN (Italy) at a depth of \\approx3600 m w.e. The total measurement time exceeds ten thousand hours. New improved half-life limits on double electron capture and electron capture with positron emission in ^{64}Zn have been set: T^{2\

  20. Isotope enrichment of metal in the process of zone melting

    The possibility of using the zone melting technique with the purpose of isotope enrichment of metal has been checked. The experiments have been carried out with zinc and cadmium wires. After the experiment the long wire has been sectioned by 15 mm and in such a state has been subjected to mass spectrometric and neutron activation analysis. The dependence of isotope enrichment with zone passage is shown. The light isotopes 64Zn in zinc and 106Cd and 108Cd in cadmium move following the zone enriching at the wire end

  1. Centrifugal enrichment of zinc isotopes, their application in medicine and in increasing radiation safety in nuclear power plants

    This paper contains the results of our research on the complete cycle of centrifuge enrichment of all zinc isotopes. The centrifuge cascade that was used to obtain the world's first zinc isotope, 7Zn, with an enrichment of more than 99.3% in gram quantities, is described. As a result of this work, gram quantities of all highly enriched zinc isotopes and hundreds of grams of depleted zinc (in the form of ZnO) with concentrations of less than 0.5% 64Zn were obtained

  2. Investigation of nα-reactions on medium mass nuclei at En 4.5-6.75 MeV

    The 39K(nα)36Cl, 40Ca(nα)37Ar and 64Zn (nα)61Ni reactions are studied within the energy values range of 4.5-6.75 MeV. The energy spectra and reaction products angular distributions are obtained. The complete and partial cross sections of the transitions into the excited states of the daughter nuclei as well as the differential cross sections are determined. The analysis of the obtained data is carried out within the frames of the optical model alongside with the data from other works

  3. Diffraction structures in high-energy electron–nucleus bremsstrahlung

    Jakubassa-Amundsen, D.H.

    2013-10-30

    The emission of hard bremsstrahlung during the collision of relativistic spin-polarized electrons with inert spin 0 and spin 1/2 nuclei is calculated within the weak-potential approximation. Diffraction structures in the polarization correlations between the beam electron and the emitted photon are predicted for collision energies in the region 50–120 MeV if the photon is emitted at backward angles. The dynamical recoil plays a dominant role concerning the location and the shape of the structures. The target nuclei {sup 19}F, {sup 64}Zn and {sup 89}Y are investigated.

  4. Calculation of excitation functions for the production of Cu and Co medical isotopes

    Copper and cobalt radioisotopes have been used for both diagnostic and therapeutic purposes in the field of nuclear medicine. There is considerable interest in 60,61,64,67Cu and 55,57Co radioisotopes for some applications like PET, SPECT imaging and targeted radiotherapy of tumors. In present study, the production of 60,61,64,67Cu and 55,57Co via 64Zn(p,a)61Cu, 67Zn(p,a)64Cu, 70Zn(p,a)67Cu, 58Ni(p,a)55Co, 60Ni(p,a)57Co, 64Zn(p,na)60Cu and 68Zn(p,na)64Cu reactions have been investigated in the range of 5-40 MeV proton incident energy. The new version of the code ALICE-2011 is used to determine the excitation functions of these nuclear reactions. The calculated excitation functions were compared with experimental results and semi-empirical cross section values of a previously developed model. (orig.)

  5. Measurement of cross section and angular distribution for 64Ze(n, α)61Ni by using gridded ionization chamber of Kr(CH4) gas

    By using a gridded ionization chamber, the angular distribution and total cross section for 64Zn(n, α)61Ni reaction were measured at 5.0, 5, 7 and 6.5 MeV, and included 10B(n, α)7Li measurement. The neutrons were produced through D(d, n)3He reaction, working gas was Kr + 4.71% CH4. Because using Kr + 4.71% CH4 as working gas, there is no interference from 16O(n, α), the authors got two dimensions events spectrums of the many excited states groups of 64Zr(n, α)61Ni and high excited state of 10B(n, α)7Li clearly at first in the world, the result of measurement show that the distribution of 64Zn(n, α)61Ni was nearly 90 degree symmetric at 5.7 MeV, and obviously backward peaked in the center of mass reference system

  6. Search for entrance channel effects in heavy ion induced fusion reactions via neutron evaporation

    Neutrons from the fusion reactions 16O+64Zn at 91 MeV and 32S+48Ti at 120 and 125 MeV have been observed in two series of complementary experiments using the time of flight technique. The energies are selected so that both the systems lead to the compound nucleus 80Sr* with the same value of the angular momentum and the excitation energy. The spectra from the asymmetric reaction 16O+64Zn are found to be consistent with the predictions of the statistical model calculations using rotating liquid drop model values of the moment of inertia and the transmission coefficients for the spherical nuclei in the inverse absorption channel. However, the experimental spectra in the case of the symmetric reaction 32S+48Ti show deviations at higher as well as lower energies from the normal statistical model calculations. This indicates the effect of the entrance channel on the dynamics of the neutron evaporation of the compound system. The effective level density parameter a is found to be smaller, indicating the evaporation at a higher temperature, for the same compound nucleus formed in the case of the symmetric system as compared to the asymmetric system

  7. Level Density Parameter: A Tool to Study the Particle Spectra

    The compound nucleus 76Kr* is formed in the heavy-ion fusion reactions by an asymmetric entrance channel 12C+64Zn and the symmetric entrance channel 31P+45Sc at the excitation energy of 75 MeV and angular momentum of 39 η. Neutron energy spectra of the asymmetric system (12C+64Zn) at different angles are well described by the statistical model predictions using the normal value of the level density parameter a = A/8 MeV-1. However, in the case of the symmetric system (31P+45Sc), the statistical model interpretation of the data requires the change in the value of a = A/10 MeV-1. The delayed evolution of the compound system in case of the symmetric 31P+45Sc system may lead to the formation of a temperature equilibrated dinuclear complex, which may be responsible for the neutron emission at higher temperature, while the protons and alpha particles are evap orated after neutron emission when the system is sufficiently cooled down and the higher λ-values do not contribute in the formation of the compound nucleus for the symmetric entrance channel in case of charged particle emission.

  8. 45V(p,γ) thermonuclear reaction rate relevant to 44Ti production in core-collapse supernovae: General estimates and shell model analysis

    The lack of knowledge of the 45V(p,γ) reaction rate has been shown to contribute a large uncertainty to the production of 44Ti in core-collapse supernovae. By considering likely contributions from resonances associated with 46Cr states that are the isobaric analog of states in 46Ti, we have determined that the currently accepted value of the 45V(p,γ) reaction rate is unlikely to be inaccurate by more than an order of magnitude. These conclusions are confirmed by the shell model calculations with the FPD6 effective interaction

  9. Resonance neutron capture in the isotopes of titanium

    The neutron capture cross sections of 46Ti, 47Ti, 48Ti, 49Ti, 50Ti have been measured from 2.75 to 300 keV with approximately 0.2 per cent energy resolution. The reduced neutron and radiative widths of the s-wave resonance exhibit correlations which, with the exception of 47Ti, are consistent with the calculated magnitudes of the valence component, assuming that the radiative widths contain an additional uncorrelated part. In 47Ti, a significant correlation is observed for J=3- resonances, although the calculated valence component is small. (Author)

  10. Spin and temperature dependence of nuclear deformation using alpha-gamma angular correlations

    Alpha-particle angular distributions with respect to the spin direction of residual nuclei have been measured in heavy-ion fusion reactions. The spin direction was determined by measuring the γ-ray angular distributions, for each event, using the spin spectrometer. α-particle anisotropies have been extracted for the compound nuclear systems: 110Sn*(94 MeV), 114Sn*(80 MeV), 138Nd*(82 MeV), 164Yb*(67 MeV) and 170Yb*(135 MeV) as a function of the α-particle energy and γ-ray multiplicity. The results are compared with statistical model calculations using transmission coefficients from a spherically symmetric optical model potential. The trend of the anisotropy coefficients below the evaporation Coulomb barrier is consistent with spherical emitting shapes in the case of the Sn* isotopes. Small deformation effects are suggested by the 138Nd* and 164Yb* data. The 170Yb* data indicate a large deformation which increases considerably with increasing spin. These results are in agreement with findings for similar systems in which the decay of the giant resonances built on excited states have been studied. 16 refs., 5 figs

  11. Collective and non-collective structures in nuclei of mass region A ≈ 125

    Generation of angular momentum in nuclei is a key question in nuclear structure studies. In single particle model, it is due to alignment of spin of individual nucleon available in the valence space, whereas coherent motion of nucleons are assumed in the collective model. The nuclei near the closed shell at Z = 50 with mass number A ≈ 120-125 represent ideal cases to explore the interplay between these competing mechanisms and the transition from non-collective to collective behavior or vice versa. Recent spectroscopic studies of nuclei in this region reveal several non-collective maximally aligned states representing the first kind of excitation mechanism, where 8-12 particles above the 114Sn align their spins to generate these states. Deformed rotational bands feeding the non-collective states in the spin range I=20-25 and excitation energies around 10 MeV have also been observed. Structure of the collective and non-collective states are discussed in the framework of Cranked-Nilsson-Strutinsky model

  12. Thin film metallic glass as an underlayer for tin whisker mitigation: A room-temperature evaluation

    Introduction of underlayer is one of the mitigation methods commonly used for the suppression of the Sn whiskering phenomenon in electronic packaging. The presence of a proper underlayer prevents the intermetallic compound formation resulting from a Cu/Sn interaction believed to be the major driving force of Sn whisker growth. Ni as an underlayer has been widely studied and industrially accepted. However, Ni underlayer suffers from its polycrystalline grain structure where grain boundaries can potentially act as a diffusion path for the Cu/Sn interaction to take place. In this study, a 100-nm-thick Zr46Ti26Ni28 thin film metallic glass (TFMG) is introduced to block the Cu/Sn interaction. Samples with and without TFMG underlayer were aged at room temperature for up to 33 days in ambient atmosphere. No Sn whisker is observed in the sample with TFMG underlayer after aging. In contrast, Sn whiskers are found in the absence of the underlayer and the whisker density increases with increasing aging time. It is found that TFMG underlayer plays an important role in effectively suppressing Sn whisker growth. - Highlights: • Zr46Ti26Ni28 thin film metallic glass (TFMG) has an amorphous structure. • TFMG underlayer influences the surface morphology of the Sn overlay. • TFMG effectively impedes interactions between Sn and Cu at room temperature. • Due to the absence of Sn/Cu interactions, formation of Sn whiskers is mitigated

  13. Thin film metallic glass as an underlayer for tin whisker mitigation: A room-temperature evaluation

    Diyatmika, Wahyu [Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Chu, J.P., E-mail: jpchu@mail.ntust.edu.tw [Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Yen, Y.W.; Chang, W.Z. [Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Hsueh, C.H. [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2014-06-30

    Introduction of underlayer is one of the mitigation methods commonly used for the suppression of the Sn whiskering phenomenon in electronic packaging. The presence of a proper underlayer prevents the intermetallic compound formation resulting from a Cu/Sn interaction believed to be the major driving force of Sn whisker growth. Ni as an underlayer has been widely studied and industrially accepted. However, Ni underlayer suffers from its polycrystalline grain structure where grain boundaries can potentially act as a diffusion path for the Cu/Sn interaction to take place. In this study, a 100-nm-thick Zr{sub 46}Ti{sub 26}Ni{sub 28} thin film metallic glass (TFMG) is introduced to block the Cu/Sn interaction. Samples with and without TFMG underlayer were aged at room temperature for up to 33 days in ambient atmosphere. No Sn whisker is observed in the sample with TFMG underlayer after aging. In contrast, Sn whiskers are found in the absence of the underlayer and the whisker density increases with increasing aging time. It is found that TFMG underlayer plays an important role in effectively suppressing Sn whisker growth. - Highlights: • Zr{sub 46}Ti{sub 26}Ni{sub 28} thin film metallic glass (TFMG) has an amorphous structure. • TFMG underlayer influences the surface morphology of the Sn overlay. • TFMG effectively impedes interactions between Sn and Cu at room temperature. • Due to the absence of Sn/Cu interactions, formation of Sn whiskers is mitigated.

  14. Pre-compound neutron evaporation in low energy heavy ion fusion reactions

    Inclusive and exclusive neutron evaporation spectra have been studied from the fusion reactions at 80 MeV 12C on 46Ti and 131 MeV 31P on 27Al, populating the compound nucleus 58Ni at the excitation energy of 79.5 MeV but in different angular momentum ranges. The evaporation residues 53Fe, 55Fe and 56Co were identified by their characteristic γ-rays. The measured energy spectra of evaporated neutrons were compared with the predictions from statistical-model calculations. In case of the asymmetric system 12C + 46Ti, the neutron spectra are well reproduced, when compared with the results from statistical-model calculations with level density parameter a=A/8MeV-1. On the contrary, the experimental spectra for the symmetric system 31P + 27Al are found to be harder than the theoretical predictions with a=A/8MeV-1. In this case, a lower value of the level density parameter a=A/10MeV-1 seems to be required to reproduce the experimental results. The dependence of the energy spectra on the entrance channel is taken as an indication that, in case of the symmetric system, the neutrons are in part emitted from a temperature equilibrated di-nuclear complex at a higher temperature before the formation of the compound nucleus

  15. Structural characterization of hollandite-type material intended for the specific containment of cesium

    Investigations on the Ba1Cs0.28Fe0.82Al1.46Ti5.72O16 hollandite powdered compound, used as potential host for radioactive cesium waste, highlight an incommensurate modulated structure and the presence of an amorphous phase. On XRD pattern, this modulation leads to two wide peaks (2 θ =19.5 and 27 angle, λ = 1.54059 A). The space group I4/m(0 0 γ) 0 0 was determined thanks to the X-Ray of single crystal analysis on a simplified Ba1.16Al2.32Ti5.68O16 material. The electron diffraction confirmed that this result could be transposed to our formulation Ba1Cs0.28Fe0.82Al1.46Ti5.72O16. This material exhibits a distribution of modulation vectors ranging from q = (0 0 0.30) to (0 0 0.48) explaining perfectly the two wide XRD peaks. In addition, an amorphous phase is observed and has been quantified (about 13%wt). (authors)

  16. Effects of isoscalar admixtures on the combined analysis of electron-nucleus and proton-nucleus ''scissors mode'' excitations in the f-p shell

    In the single j shell approximation, only the isovector amplitudes of electron-nucleus or proton-nucleus scattering contribute to the excitation of 1+ states from the J=0+ targets of even-even nuclei, provided the excitation is a one-step process. However, when configuration mixing is put in, one also obtains contributions from isoscalar amplitudes, which are here studied for various nuclei in the f-p shell endash 44Ti, 46Ti, 48Ti and 50Cr. A comparison of the cross-conjugate pairs 46Ti and 50Cr is made. The decomposition of the electron-nucleus scattering into an orbital and spin part is made. The isoscalar effects are small and are unable to explain the discrepancies between the experimental analysis and the shell model calculations with regards to the variation of the orbit to spin ratio for various nuclei. However, there is probably hidden orbital strength in a state in 50Cr for which the spin and orbit excitation amplitudes interfere destructively

  17. Zinc isotope ratios of bones and teeth as new dietary indicators: results from a modern food web (Koobi Fora, Kenya)

    Jaouen, Klervia; Beasley, Melanie; Schoeninger, Margaret; Hublin, Jean-Jacques; Richards, Michael P.

    2016-01-01

    In order to explore the possibilities of using zinc (Zn) stable isotope ratios as dietary indicators, we report here on the measurements of the ratio of stable isotopes of zinc (66Zn/64Zn, expressed here as δ66Zn) in bioapatite (bone and dental enamel) of animals from a modern food web in the Koobi Fora region of the Turkana Basin in Kenya. We demonstrate that δ66Zn values in both bone and enamel allow a clear distinction between carnivores and herbivores from this food web. Differences were also observed between browsers and grazers as well as between carnivores that consumed bone (i.e. hyenas) compared to those that largely consume flesh (i.e. lions). We conclude that Zn isotope ratio measurements of bone and teeth are a new and promising dietary indicator. PMID:27189145

  18. Zinc isotope ratios of bones and teeth as new dietary indicators: results from a modern food web (Koobi Fora, Kenya).

    Jaouen, Klervia; Beasley, Melanie; Schoeninger, Margaret; Hublin, Jean-Jacques; Richards, Michael P

    2016-01-01

    In order to explore the possibilities of using zinc (Zn) stable isotope ratios as dietary indicators, we report here on the measurements of the ratio of stable isotopes of zinc ((66)Zn/(64)Zn, expressed here as δ(66)Zn) in bioapatite (bone and dental enamel) of animals from a modern food web in the Koobi Fora region of the Turkana Basin in Kenya. We demonstrate that δ(66)Zn values in both bone and enamel allow a clear distinction between carnivores and herbivores from this food web. Differences were also observed between browsers and grazers as well as between carnivores that consumed bone (i.e. hyenas) compared to those that largely consume flesh (i.e. lions). We conclude that Zn isotope ratio measurements of bone and teeth are a new and promising dietary indicator. PMID:27189145

  19. Market of stable isotopes produced by gas centrifuges: status and prospects

    The major consumers on the market of enriched stable isotopes traditionally include nuclear industry, medicine and life sciences, and new technical and scientific applications. The beginning of new millennium has brought the wide application of enriched stable isotopes in fundamental physics experiments that needed tens and hundreds kilograms of various stable isotopes of middle and heavy masses. In addition, the needs of nuclear power industry to develop materials to be used in nuclear power plants capable to reduce formation of radioactive by-products and to prevent cracking in certain metallic components led to production of big amounts of different compounds of zinc depleted with the 64Zn isotope. All these problems have been solved successfully by means of the gas centrifuge technology applied for separation of isotopes other than uranium. As a result the market of enriched/depleted stable isotopes has changed radically in recent years. (authors)

  20. Mediating conducting polymer growth within hydrogels by controlling nucleation

    A. J. Patton

    2015-01-01

    Full Text Available This study examines the efficacy of primary and secondary nucleation for electrochemical polymerisation of conductive polymers within poly(vinyl alcohol methacrylate hydrogels. The two methods of nucleation investigated were a primary heterogeneous mechanism via introduction of conductive bulk metallic glass (Mg64Zn30Ca5Na1 particles and a secondary mechanism via introduction of “pre-polymerised” conducting polymer within the hydrogel (PEDOT:PSS. Evidence of nucleation was not seen in the bulk metallic glass loaded gels, however, the PEDOT:PSS loaded gels produced charge storage capacities over 15 mC/cm2 when sufficient polymer was loaded. These studies support the hypothesis that secondary nucleation is an efficient approach to producing stand-alone conducting hydrogels.

  1. Production of carrier-free radioactive copper from neutron irradiated zinc targets

    The present study describes the production of carrier-free radioactive copper from natural zinc metal as target material irradiated at ETRR-2 and ETRR+1 research reactors, Egypt. Radioactive copper-64 and 67 were prepared according to the fast neutron reaction 64 Zn (n,p)64 Cu and 67 Zn (n,p)67 Cu. The zinc chloride radiotracer in 8 M HCl acid solutions was loaded onto the anion exchanger resin (Dowex 1 x 8, Cl - ion form, 200-400 mesh, i.d. 0.9 x 10 cm) at flow rate of 0.8 ml/min. Carrier-free radioactive Cu was eluted from the resin by 2.5 M HCl leaving zinc chloride retained on the resin. Quality control investigations including radionuclidic, radiochemical and chemical purity of carrier-free radioactive Cu product has proved its suitability for nuclear medicine use

  2. Elastic scattering and reaction mechanisms of the halo nucleus $^{11}$Be around the Coulomb barrier

    Di Pietro, A; Fisichella, M; Borge, M J G; Randisi, G; Milin, M; Figuera, P; Gomez-Camacho, J; Raabe, R; Amorini, F; Fraile, L M; Rizzo, F; Zadro, M; Torresi, D; Wenander, F; Pellegriti, M G; Papa, M; Jeppesen, H; Santonocito, D; Scuderi, V; Acosta, L; Perez-Bernal, F; Tengblad, O; Lattuada, M; Musumarra, A; Scalia, G; Maira Vidal, A; Voulot, D

    2010-01-01

    Collisions induced by $^{9}$Be, $^{10}$Be, $^{11}$Be on a $^{64}$Zn target at the same c. m. energy were studied. For the first time, strong effects of the $^{11}$Be halo structure on elastic-scattering and reaction mechanisms at energies near the Coulomb barrier are evidenced experimentally. The elastic-scattering cross section of the $^{11}$Be halo nucleus shows unusual behavior in the Coulomb-nuclear interference peak angular region. The extracted total-reaction cross section for the $^{11}$Be collision is more than double the ones measured in the collisions induced by $^{9}$Be, $^{10}$Be. It is shown that such a strong enhancement of the total-reaction cross section with $^{11}$Be is due to transfer and breakup processes.

  3. Zinc isotope ratios of bones and teeth as new dietary indicators: results from a modern food web (Koobi Fora, Kenya)

    Jaouen, Klervia; Beasley, Melanie; Schoeninger, Margaret; Hublin, Jean-Jacques; Richards, Michael P.

    2016-05-01

    In order to explore the possibilities of using zinc (Zn) stable isotope ratios as dietary indicators, we report here on the measurements of the ratio of stable isotopes of zinc (66Zn/64Zn, expressed here as δ66Zn) in bioapatite (bone and dental enamel) of animals from a modern food web in the Koobi Fora region of the Turkana Basin in Kenya. We demonstrate that δ66Zn values in both bone and enamel allow a clear distinction between carnivores and herbivores from this food web. Differences were also observed between browsers and grazers as well as between carnivores that consumed bone (i.e. hyenas) compared to those that largely consume flesh (i.e. lions). We conclude that Zn isotope ratio measurements of bone and teeth are a new and promising dietary indicator.

  4. Coulomb excitation of {sup 140}Nd - measuring the B(E2) value of the first 2{sup +} state at REX-ISOLDE

    Bauer, Christopher; Pietralla, Norbert; Bloch, Timo; Boenig, Sabine; Kroell, Thorsten; Leske, Joerg; Scheck, Marcus; Stahl, Christian; Stegmann, Robert [IKP, TU Darmstadt (Germany); Rainovski, Georgi; Damyanova, Antoaneta; Danchev, Miroslav; Gladnishki, Kalin [University of Sofia (Bulgaria); Blazhev, Andrey; Moschner, Kevin [IKP, Universitaet zu Koeln (Germany); Pakarinen, Janne [CERN, Geneva (Switzerland); Werner, Volker [WNSL, Yale University, New Haven, CT (United States)

    2012-07-01

    A radioactive beam of {sup 140}Nd was impinging on a 1.40 mg/cm{sup 2} {sup 48}Ti as well as a 1.55mg/cm{sup 2} {sup 64}Zn target. Gamma rays were detected by the MINIBALL array and a DSSD was used for particle identification. The transition strength of the first 2{sup +} state to the 0{sup +} ground state of neutron-deficient {sup 140}Nd was measured to be 30(5) W.u. This result deviates from empirical rules for quadrupole collectivity and microscopic predictions. This unexpected behavior prompts for new, refined microscopic calculations and might be related to the shell stabilization of the quadrupole isovector valence shell excitations. The result is important for the planned experiment at HIE-ISOLDE, which aims to identify the one-phonon mixed-symmetry 2{sup +} state of {sup 140}Nd.

  5. Anomalous behaviour of transition probabilities in 75Kr

    The two collective bands of 75Kr have been extended up to spin 21/2 using the compound reactions 64Zn(14N, p2n)75Kr and 50Cr(28Si, 2pn)75Kr. Spins and parities were assigned from neutron-gated γ angular-distributions and excitation functions using the OSIRIS Anti Compton Spectrometer. The bands are interpreted to be built on well-deformed Nilsson states: [442]5/2 and [301]3/2. Energies and mixing ratios for both bands can be reproduced within the 'single particle and rotor' model, while the experimental Q0(I->I-1)/Q0(I->I-2) ratios exhibit large deviations by a factor 4 to 6 from theoretical values. (orig.)

  6. Thermal properties of zinc isotopes in the static path approximation

    Employing a quadrupole-quadrupole interaction Hamiltonian in the so-called static path approximation, which is based on path integration in the space of single-particle potential fields, we have calculated the excitation energy, level density, and level density parameter of some of the zinc isotopes with neutron numbers, N=34, 40, 44, and 46 at finite temperatures, T≤2.0 MeV. Using a cranking Hamiltonian (with rotation about the X axis) in the same approach we have also studied the behavior of the moment of inertia as a function of rotational frequency (ω) and temperature for 64Zn, taking it as an illustrative example. At low temperature (T∼0.5 MeV) the effect of rotation alignment is seen at ω∼1.0 MeV whereas at T∼2.0 MeV the moment of inertia becomes almost independent of ω, indicative of a rigid body behavior

  7. Reaction mechanisms in collisions induced by 8B beam close to the barrier

    The aim of the proposed experiment is to investigate on the reaction dynamics of proton-halo induced collisions at energies around the Coulomb barrier where coupling to continuum effects are expected to be important. We propose to measure $^{8}$B+$^{64}$Zn elastic scattering angular distribution together with the measurement, for the first time, of p-$^{7}$Be coincidences coming from transfer and/or break-up of $^{8}$B. The latter will allow a better understanding of the relative contribution of elastic $\\textit{vs}$ non-elastic break-up in reactions induced by extremely weakly-bound nuclei. We believe that with the availability of the post accelerated $^{8}$B beam at REX-ISOLDE we will be able to collect for the first time high quality data for the study of such an important topic.

  8. Benchmark experiment on the model of fusion reactor blanket with uranium neutron multiplier

    Benchmark experiment on the model of thermonuclear reactor blanket with 14 MeV neutron source is described. The model design corresponds to the known concept of the fast hybrid blanket with 238U neutron multiplier and main tritium production on 6Li. Detailed measurements of the following process velocities were carried out: tritium production on lithium isotopes; reactions modelling tritium production; (n, γ) and (n, 2n) processes for 238U; fission reactions for 235,238U, 239Pu, 237Np. Neutron flux integral measurements were performed by a set of threshold detectors on the basic of the 115In(n, n'), 204Pb(n, n'), 64Zn(n, p), 27Al(n, p), 56Fe(n, p), 107Ag(n, 2n), 63Cu(n, 2n) and 64(n, 2n) reactions

  9. Neutron evaporation as a probe for dynamical effects in heavy ion fusion reactions

    The compound nucleus 76Kr* was populated at the excitation energy of 75 MeV and angular momentum of 39 (ℎ/2π) in fusion reactions with two complementary, mass-symmetric (31P+45Sc) and mass asymmetric (12C+64Zn) entrance channels. The neutron evaporation spectra were measured and compared with the predictions of the statistical model calculations. The results for the mass-asymmetric reaction are found to be consistent with the predictions of the statistical model calculations. However, for the mass-symmetric reaction (31P+45Sc), the experimental spectra are found to be harder than the theoretical neutron spectra. The dynamical model calculations of Feldmeier show that the formation time for the compound nucleus for the symmetric system is relatively larger as compared to the asymmetric system

  10. Comparison of nuclear data of 64Cu production using an accelerator by TALYS 1.0 code

    Sadeghi Mahdi

    2010-01-01

    Full Text Available The extensive use of 64Cu (T1/2 = 12.7 h as a positron and electron emitter radioisotope in recent years has ensured its potential to serve a dual role in the development of molecular agents in PET and radioimmunotheraphy drugs in oncology. The TALYS 1.0 code was used to calculate excitation functions for induced proton, deuteron and alfa-particles on 64Zn, 66Zn, 67Zn, 68Zn, 70Zn, 62Ni, and 64Ni up to 50 MeV. According to the data acquired by the TALYS 1.0 code, thick-target integral yield of the induced charged particles on the enriched targets was achieved.

  11. Experimental reconstruction of primary fragments with kinematical focusing method

    An experimental method was used to evaluate the primary isotope yields of semi-central collisions in the reaction system 64Zn+112Sn at 40A MeV, The characteristic nature of the hot nuclear matter at the time of the isotope formation was studied. The multiplicities of light particles (LPs) associated with intermediate mass fragments (IMFs) were determined experimentally by using a kinematical focusing technique. The primary isotope distributions, reconstructed by a Monte Carlo method, were compared with those of the AMD-Gemini simulations. ac/T=0.11 and asym/T=3.34 were extracted from the reconstructed primary fragments yield. These are consistent with those of the primary fragments of the AMD simulation. (authors)

  12. The $^{63}$Ni(n,$\\gamma$) cross section measured with DANCE

    Weigand, M; Couture, A; Göbel, K; Heftrich, T; Jandel, M; Käppeler, F; Lederer, C; Kivel, N; Korschinek, G; Krticka, M; O'Donnell, J M; Ostermöller, J; Plag, R; Reifarth, R; Schumann, D; Ullmann, J L; Wallner, A

    2015-01-01

    The neutron capture cross section of the s-process branch nucleus $^{63}$Ni affects the abundances of other nuclei in its region, especially $^{63}$Cu and $^{64}$Zn. In order to determine the energy dependent neutron capture cross section in the astrophysical energy region, an experiment at the Los Alamos National Laboratory has been performed using the calorimetric 4$\\pi$ BaF$_2$ array DANCE. The (n,$\\gamma$) cross section of $^{63}$Ni has been determined relative to the well known $^{197}$Au standard with uncertainties below 15%. Various $^{63}$Ni resonances have been identified based on the Q-value. Furthermore, the s-process sensitivity of the new values was analyzed with the new network calculation tool NETZ.

  13. 63Ni (n ,γ ) cross sections measured with DANCE

    Weigand, M.; Bredeweg, T. A.; Couture, A.; Göbel, K.; Heftrich, T.; Jandel, M.; Käppeler, F.; Lederer, C.; Kivel, N.; Korschinek, G.; Krtička, M.; O'Donnell, J. M.; Ostermöller, J.; Plag, R.; Reifarth, R.; Schumann, D.; Ullmann, J. L.; Wallner, A.

    2015-10-01

    The neutron capture cross section of the s -process branch nucleus 63Ni affects the abundances of other nuclei in its region, especially 63Cu and 64Zn. In order to determine the energy-dependent neutron capture cross section in the astrophysical energy region, an experiment at the Los Alamos National Laboratory has been performed using the calorimetric 4 π BaF2 array DANCE. The (n ,γ ) cross section of 63Ni has been determined relative to the well-known 197Au standard with uncertainties below 15%. Various 63Ni resonances have been identified based on the Q value. Furthermore, the s -process sensitivity of the new values was analyzed with the new network calculation tool NETZ.

  14. Reactor production of 64Cu and 67Cu using enriched zinc target material

    Initial development work and trial irradiations were conducted to produce the in-demand medical isotopes 64Cu and 67Cu via the reactor-based fast neutron 64Zn(n,p)64Cu and 67Zn(n,p)67Cu reactions using enriched zinc targets. Boron-nitride shielded sample holders were used to reduce the thermal neutron flux to the zinc targets and diminish the production of undesired 65Zn. Irradiated oxide targets were dissolved and preliminary separations achieved copper yields of ∼95 % and zinc separations factors greater than 103 after one ion exchange pass. Further development would allow the production of mCi levels of 64Cu and 67Cu per irradiation, providing sufficient activity for small mammal research studies. (author)

  15. ZnWO_4 crystals as detectors for double beta decay and dark matter experiments

    Danevich, F A; Nagorny, S S; Poda, D V; Tretyak, V I; Yurchenko, S S; Zdesenko, Y G; Zdesenko, Yu.G.

    2004-01-01

    Energy resolution, alpha/beta ratio, and the pulse shape discrimination ability of the ZnWO_4 crystal scintillators were studied. The radioactive contamination of a ZnWO_4 crystal was investigated in the Solotvina Underground Laboratory. Possibilities to apply ZnWO_4 crystals for the dark matter and double beta decay searches are discussed. New improved half-life limits on double beta decay in zinc isotopes were established, in particular, for EC\\beta^+ decay of 64-Zn as: T_1/2^2nu > 8.9 10^18 yr and T_1/2^0nu > 3.6 10^18 yr, both at 68% CL.

  16. Diffusion studies in ZnTe for an active role of vacancies

    Investigations on the jump frequencies for various isotopes of cations and anions in ZnTe for an active role of vacancies are reported. Lattice dynamical calculations of diffusion are carried out using the scattering matrix formalism and reaction co-ordinates. The jump frequency and isotope effect for 126Te, 128Te, 64Zn, 66Zn, 68Zn are estimated for temperatures 1000, 1200, and 1500 K. The isotope effect in the case of Te diffusion is of the order of 50%. The diffusion of Zn in ZnTe can be explained lattice dynamically only by considering the contributions from various defects (single vacancies, Frenkel defect pairs). It can be concluded that Zn diffusion in ZnTe is different from Te diffusion in ZnTe

  17. A study on zinc isotope fractionation in a benzo crown resin/acetone system

    Zinc isotope fractionation has been studied in different cavities of crown ether resins that were synthesized in porous silica beads. Displacement chromatography was performed, as a breakthrough manner, in glass columns by feeding in a zinc chloride solution. From the mass analysis of effluents, the heavier isotopes of zinc were enriched at the beginning of the zinc adsorption band. The front maximum enrichment (1.0168), separation coefficient (8.1 x 10-4), and smaller HETP (0.205 cm) for the isotopic pair 68Zn/64Zn were obtained with the use of the benzo-15-crown-5 resin. Zinc isotope fractionation was obviously affected by the cavity size of the crown ethers. (author)

  18. Zinc isotope separation by phenol formaldehyde type 15-crown-5 resin in organic solvents

    Zinc adsorption and isotope separation by newly synthesized benzo-15-crown-5 resin was evaluated using various solvents. This resin was synthesized in the pores of silica beads for chromatography use. Larger adsorption of zinc was obtained in the case of acetic acid derivatives than in protic solvent such as water and alcohol by the batch treatment. The displacement chromatography was conducted to study zinc isotope separation. The isotope separation coefficient ε=0.32x10-3, 0.69x10-3 and HETP=0.2268, 0.3968 cm were determined for isotopic pair of 68Zn/64Zn at 25degC by five meters migration experiment using methyl isobutyl ketone and acetic acid, respectively. The improvement of enrichment ratio is very small between 1 and 5 m migration. Hydrogen chloride and/or water obviously reduce zinc adsorption to this resin. (author)

  19. Experimental reconstruction of primary hot isotopes and characteristic properties of the fragmenting source in the heavy ion reactions near the Fermi energy

    Lin, W; Rodrigues, M R D; Kowalski, S; Wada, R; Huang, M; Zhang, S; Chen, Z; Wang, J; Xiao, G Q; Han, R; Jin, Z; Liu, J; Ren, P; Shi, F; Keutgen, T; Hagel, K; Barbui, M; Bottosso, C; Bonasera, A; Natowitz, J B; Materna, T; Qin, L; Sahu, P K; Zheng, H

    2014-01-01

    The characteristic properties of the hot nuclear matter existing at the time of fragment formation in the multifragmentation events produced in the reaction $^{64}$Zn + $^{112}$Sn at 40 MeV/nucleon are studied. A kinematical focusing method is employed to determine the multiplicities of evaporated light particles, associated with isotopically identified detected fragments. From these data the primary isotopic yield distributions are reconstructed using a Monte Carlo method. The reconstructed yield distributions are in good agreement with the primary isotope distributions obtained from AMD transport model simulations. Utilizing the reconstructed yields, power distribution, Landau free energy, characteristic properties of the emitting source are examined. The primary mass distributions exhibit a power law distribution with the critical exponent, $A^{-2.3}$, for $A \\geq 15$ isotopes, but significantly deviates from that for the lighter isotopes. Landau free energy plots show no strong signature of the first orde...

  20. A self-consistent determination of density, temperature and symmetry energy for nuclear multi-fragmentation through primary fragment yield reconstruction

    Lin, W; Rodrigues, M R D; Kowalski, S; Wada, R; Huang, M; Zhang, S; Chen, Z; Wang, J; Xiao, G Q; Han, R; Jin, Z; Liu, J; Shi, F; Keutgen, T; Hagel, K; Barbui, M; Bottosso, C; Bonasera, A; Natowitz, J B; Kim, E J; Materna, T; Qin, L; Sahu, P K; Schmidt, K J; Wuenschel, S; Zheng, H

    2014-01-01

    For the first time primary hot isotope distributions are experimentally reconstructed in intermediate heavy ion collisions and used with antisymmetrized molecular dynamics (AMD) calculations to determine density, temperature and symmetry energy coefficient in a self-consistent manner. A kinematical focusing method is employed to reconstruct the primary hot fragment yield distributions for multifragmentation events observed in the reaction system $^{64}$Zn + $^{112}$Sn at 40 MeV/nucleon.The reconstructed yield distributions are in good agreement with the primary isotope distributions of AMD simulations. The experimentally extracted values of the symmetry energy coefficient relative to the temperature, $a_{sym}/T$, are compared with those of the AMD simulations with different density dependence of the symmetry energy term.The calculated $a_{sym}/T$ values changes according to the different interactions. By comparison of the experimental values of $a_{sym}/T$ with those of alculations, the density of the source ...

  1. Measurement of (n,2n) reaction cross-sections on isotopes of zinc, germanium and scandium in neutron energy range 13.82-14.7 MeV

    The cross-sections for the reactions 64Zn(n,2n)63Zn, 76Ge (n,2n)75m+gGe and 45Sc(n,2n)44mSc were measured in the energy range 13.82-14.71 MeV. The activation technique was used in combination with high resolution HPGe detector gamma-ray spectroscopy. Neutrons were produced via D-T reaction at J-25 neutron generator of the Institute of Nuclear Science and Technology, AERE, Dhaka, Bangladesh. The neutron flux at each energy was determined using monitor reaction 27Al(n, α)24Na. The nuclear model calculations using the computer codes SINCROS-II and EXIFON were undertaken to describe the excitation functions of the investigated reactions. (author)

  2. Neutrinoless double positron decay and positron emitting electron capture in the interacting boson model

    Barea, J; Iachello, F

    2015-01-01

    Neutrinoless double-$\\beta$ decay is of fundamental importance for determining the neutrino mass. Although double electron ($\\beta^-\\beta^-$) decay is the most promising mode, in very recent years interest in double positron ($\\beta^+\\beta^+$) decay, positron emitting electron capture ($EC\\beta^+$), and double electron capture ($ECEC$) has been renewed. We present here results of a calculation of nuclear matrix elements for neutrinoless double-$\\beta^+$ decay and positron emitting electron capture within the framework of the microscopic interacting boson model (IBM-2) for $^{58}$Ni, $^{64}$Zn, $^{78}$Kr, $^{96}$Ru, $^{106}$Cd, $^{124}$Xe, $^{130}$Ba, and $^{136}$Ce decay. By combining these with a calculation of phase space factors we calculate expected half-lives.

  3. Nuclear structure effects in high-energy bremsstrahlung from spin-0 and spin-1/2 nuclei

    Jakubassa-Amundsen, Doris [University of Munich (Germany)

    2014-07-01

    Bremsstrahlung from relativistic spin-polarized electrons colliding with inert nuclei is calculated by taking into account the nuclear form factors and the kinematical recoil. For the spin-1/2 nuclei additional contributions from the anomalous magnetic moment and the dynamical recoil are considered. Electron bremsstrahlung is described with the help of semirelativistic wavefunctions while nuclear bremsstrahlung, when present, is treated within the Born approximation. The triply differential bremsstrahlung cross section is integrated over the electron scattering angle to study the polarization correlations between the beam electron and the emitted photon. Results are shown for 20-120 MeV electrons colliding with protons, 19F, 64Zn and 89Y. It is also attempted to explain the background in electron spectra from nuclear excitation in terms of bremsstrahlung. As an example the 180 degree spectrum from exciting the giant M2 resonance in 90Zr by 42.7 MeV electrons is analyzed.

  4. Study of covariances involved in the k0 method of neutron activation analysis

    This work aimed the development of a methodology for the treatment of uncertainty in the k0 Method for Neutron Activation Analysis (NAA), comprehensively and accurately, by applying the covariance analysis methodology. All parameters involved in determining the concentration of a given element were analyzed with criteria in order to establish the correlations among them. Also established were the possible correlations between the concentrations of different elements for the same sample and for different samples. This procedure generated a large number of correlations that have been rigorously addressed. Data for analysis were obtained experimentally by means of irradiations performed at 24A irradiation position, near the core of the IEA-R1 research reactor, located at IPEN-CNEN/SP. The parameters α and f, characterizing the neutron field were determined by applying several methods from the literature. A detailed statistical treatment was applied to each measurement, verifying the various uncertainties and partial correlations. In order to deepen the study, targets of 64Zn and 68Zn were chosen, for which the nuclear parameters k0 and Q0 showed discrepancies in the literature in order to determine them experimentally. For 64Zn, the values for these parameters resulted 5.63(8) x 10-3 and 1.69(6), respectively. For 68Zn they resulted 4.00(6) x 10-4 and 2.34(4), respectively. These values were compared with data from the literature. The Monte Carlo method was applied at various stages of study, to allow accurate determination of some parameters needed for the complete data analysis. (author)

  5. Nucleosynthesis in Electron Capture Supernovae of Asymptotic Giant Branch Stars

    Wanajo, S.; Nomoto, K.; Janka, H.-T.; Kitaura, F. S.; Müller, B.

    2009-04-01

    We examine nucleosynthesis in the electron capture supernovae of progenitor asymptotic giant branch stars with an O-Ne-Mg core (with the initial stellar mass of 8.8 M sun). Thermodynamic trajectories for the first 810 ms after core bounce are taken from a recent state-of-the-art hydrodynamic simulation. The presented nucleosynthesis results are characterized by a number of distinct features that are not shared with those of other supernovae from the collapse of stars with iron core (with initial stellar masses of more than 10 M sun). First is the small amount of 56Ni (0.002-0.004 M sun) in the ejecta, which can be an explanation for the observed properties of faint supernovae such as SNe 2008S and 1997D. In addition, the large Ni/Fe ratio is in reasonable agreement with the spectroscopic result of the Crab nebula (the relic of SN 1054). Second is the large production of 64Zn, 70Ge, light p-nuclei (74Se, 78Kr, 84Sr, and 92Mo), and in particular, 90Zr, which originates from the low Ye (0.46-0.49, the number of electrons per nucleon) ejecta. We find, however, that only a 1%-2% increase of the minimum Ye moderates the overproduction of 90Zr. In contrast, the production of 64Zn is fairly robust against a small variation of Ye . This provides the upper limit of the occurrence of this type of events to be about 30% of all core-collapse supernovae.

  6. Realization of a gamma multiplicity filter and gamma multiplicity measurements

    A gamma multiplicity filter for the study of reaction mechanism has been realised. It's composed of six NaI(Tl) counters. The flexibility of the geometry allows many configurations. This set up has been tested with gamma radioactive sources and with the 252Cf source to resolve problems of gamma-efficiency of the NaI(Tl) counters and the contamination of neutrons in these detectors. A logical electronic unit (Encodeur) has been constructed and the around electronic has been developped. This gamma multiplicity filter has been coupled with a detector of high resolution Ge(Li), and used in two reactions: 12C + 55Mn at E(12C) = 54 MeV; α + 63Cu at E(α) = 52 MeV. The dominant process is the fusion-evaporation. The compound nucleus 67Ga, is formed at the same excitation energy. The values of multiplicities Msub(γ) have been extracted using a program based on the formalism of W.J. Ockels. The fractionalization of the angular momentum is well observed for some residual nuclei (63Zn, 64Zn, 65Zn), and for each residual nucleus, the average gamma multiplicity is lower with projectile α than that with projectile 12C. For the most strongly output channel p2n, an entry point for the 64Zn has been determined in the reactions. All these observations are in good agreement with those published, in the same region (f-p shell) of nuclei. This set up can be coupled with different central detector as, ''X'', neutrons charged particles detectors, and will be used with the new machine SARA to make a systematic study of transfer of angular momentum to the fragments at 30 MeV/A

  7. Anomalous behavior of the level density parameter in neutron and charged particle evaporation

    The compound nucleus 76Kr* was populated at the excitation energy of 75 MeV and angular momentum of 39(ℎ/2π) in fusion reactions with two complementary, mass-symmetric (31P+45Sc) and mass-asymmetric (12C+64Zn) entrance channels. The neutron evaporation spectra were measured and compared with the predictions of statistical model calculations using the transmission coefficients for the spherical nuclei in the inverse absorption channel, the rotating liquid drop model moment of inertia, and the normal systematic value of A/8 for the level density parameter a. The results for the mass-asymmetric reaction are found to be consistent with the predictions of the statistical model calculations. However, for the mass-symmetric reaction (31P+45Sc), the experimental spectra are found to be harder than the theoretical neutron spectra and the statistical model calculations require a lower value of A/10 for the parameter a to reproduce the shape of the experimental spectra, indicating the neutron to be evaporated at higher temperature for the same excitation energy and angular momentum in symmetric system. According to the dynamical model, the formation time (37x10-22 sec) of the compound nucleus for the symmetric 31P+45Sc system is significantly higher than that (29x10-22 sec) for the asymmetric 12C+64Zn system. This may probably lead to the formation of a temperature-equilibrated dinuclear complex that may be responsible for neutron emission at higher temperature in the case of the symmetric system

  8. Investigation into the semimagic nature of the tin isotopes through electromagnetic moments

    Allmond, J. M.; Stuchbery, A. E.; Galindo-Uribarri, A.; Padilla-Rodal, E.; Radford, D. C.; Batchelder, J. C.; Bingham, C. R.; Howard, M. E.; Liang, J. F.; Manning, B.; Pain, S. D.; Stone, N. J.; Varner, R. L.; Yu, C.-H.

    2015-10-01

    A complete set of electromagnetic moments, B (E 2 ;01+→21+) ,Q (21+) , and g (21+) , have been measured from Coulomb excitation of semimagic 112,114,116,118,120,122,124Sn (Z =50 ) on natural carbon and titanium targets. The magnitude of the B (E 2 ) values, measured to a precision of ˜4 % , disagree with a recent lifetime study [Phys. Lett. B 695, 110 (2011), 10.1016/j.physletb.2010.11.012] that employed the Doppler-shift attenuation method. The B (E 2 ) values show an overall enhancement compared with recent theoretical calculations and a clear asymmetry about midshell, contrary to naive expectations. A new static electric quadrupole moment, Q (21+) , has been measured for 114Sn. The static quadrupole moments are generally consistent with zero but reveal an enhancement near midshell; this had not been previously observed. The magnetic dipole moments are consistent with previous measurements and show a near monotonic decrease in value with neutron number. The g -factor measurements in Sn,114112 establish the recoil-in-vacuum method for states with τ ˜0.5 ps and hence demonstrate that this method can be used for future g -factor measurements on proton-rich isotopes toward 100Sn. Current theory calculations fail to reproduce the electromagnetic moments of the tin isotopes. The role of 2p-2h and 4p-4h intruders, which are lowest in energy at midshell and outside of current model spaces, needs to be investigated in the future.

  9. Dependence of strength og polycrystalline ferroelectric TsTS-22 on loading velocity

    The strength of polycrystalline ferroelectric Pb0.95Sr0,05(Zr0,46Ti0.54)O3 + 0.78 wt. % Cr2O3 (TsTS-22) by bending is measured within the range of loading velocities of 5 x 10-2 MPa/s and temperatures of 293-873 K (including Curie temperature Tc = 593 K). The interpretation of results is presented within the frames of the relaxation model of the friable destruction. The effective activation volume of destruction process is determined with application of the strength dependence on the sample loading velocity under various temperatures. Changes in the activation features in the phase transition area are discussed

  10. Evaluation of the (n,p) cross sections of natural Ti and its isotopes from thresholds to 20 MeV

    The titanium isotopes (n,p) cross sections are based upon renormalized experimental data or deduced from statistical model calculations where measurements were not available. Some of these cross sections, notably the 46Ti (n,p), 47Ti (n,p) and 48Ti (n,p), which find wide use as dosimetry indicators, are compared here with the corresponding ENDF/BIV dosimetry file data. The (n,p) elemental cross section is constructed from the weighted isotopic components. Our evaluation and the corresponding ENDF/BIV data are compared showing the great difference between both results, especially below 10 MeV. Moreover the new data exhibit some structure characteristics of the 47Ti (n,p) cross section. The present Ti (n,p) data are intended to be included in the ENDF/BV evaluation

  11. Onset of collectivity in the ground-state band of 50Cr

    Transient field precessions of the first excited states in 50Cr have been measured. The states were excited by the inverse 12C(40Ca, 2p)50Cr reaction and the recoil nuclei traversed a thick gadolinium foil, where they experienced the rotation. The observed precessions, for the 2+,4+,6+,8+ states of the ground-state band, were equal within experimental error indicating these states have g factors similar to that of the 2+ state value of 0.55±0.10 measured previously. This feature is contrary to the predictions of the shell model and suggests a higher collectivity for the ground-state band. Limited results were also obtained for the cross conjugate nucleus 46Ti supporting this conclusion

  12. Angular momentum projection of cranked Hartree-Fock states: Application to terminating bands in A∼44 nuclei

    We present the first systematic calculations based on the angular momentum projection of cranked Slater determinants. We propose the Iy→I scheme, by which one projects the angular momentum I from the one-dimensional cranked state constrained to the average spin projection of y>=I. Calculations performed for the rotational band in 46Ti show that the AMP Iy→I scheme offers a natural mechanism for correcting the cranking moment of inertia at low spins and shifting the terminating state up by ∼2 MeV, in accordance with data. We also apply this scheme to high-spin states near the band termination in A∼44 nuclei and compare results thereof with experimental data, shell-model calculations, and results of the approximate analytical symmetry-restoration method proposed previously

  13. Systematic study of proton-neutron pairing correlations in the nuclear shell model

    A shell-model study of proton-neutron pairing in 2p1f shell nuclei using a parametrized Hamiltonian that includes deformation and spin-orbit effects as well as isoscalar and isovector pairing is reported. By working in a shell-model framework we are able to assess the role of the various modes of proton-neutron pairing in the presence of nuclear deformation without violating symmetries. Results are presented for 44Ti, 45Ti, 46Ti, 46V, and 48Cr to assess how proton-neutron pair correlations emerge under different scenarios. We also study how the presence of a one-body spin-obit interaction affects the contribution of the various pairing modes.

  14. Nuclear structure theory in spin- and number-conserving quasiparticle configuration spaces: First applications

    Schmid, K.W.; Gruemmer, F.; Faessler, A.

    1984-01-01

    In the first part of the present series of two papers we discussed several nuclear structure models all working in configuration spaces consisting of spin- and number-projected quasiparticle determinants. In the present paper a particular version of the numerically simplest of these models is presented. This model approximates the nuclear wave functions by linear combinations of the angular momentum- and particle number-projected Hartree-Fock-Bogoliubov vacuum and the equally spin- and number-projected two quasiparticle excitations with respect to it. The model allows the use of realistic two body interactions and rather large model spaces. It can hence be applied to a large number of nuclear structure problems in various mass regions. First applications have been performed for the nuclei /sup 20/Ne, /sup 22/Ne, /sup 46/Ti, and /sup 164/Er. In all these cases the results are very encouraging.

  15. Synthesis of amorphous Ti-Al alloys by mechanical alloying of elemental powders

    张俊红; 黄伯云; 贺跃辉; 周科朝; 刘咏

    2002-01-01

    Blended elemental powders with the nominal compositions (mole fraction, %) of Ti54Al46, Ti52Al48 and Ti50Al50 were mechanically alloyed in a planetary ball milling system for up to 100h.The structure evolution in these powders was characterized by scanning electron microscope, X-ray diffraction and differential thermal a nalysis techniques. It was found that elemental powders were progressively trans formed into nanocrystalline Ti(Al) supersaturated solid solution, then into amor phous phase. With increasing Al content, the formation of a fully Ti(Al) supersa turated solid solution and amorphous phase were accelerated, which are attributed to the fine grain size. And the grain size condition for formation of amorpho us phase in this system is ≤16 nm.

  16. Isospin aspects in nuclear reactions involving Ca beams at 25 MeV/nucleon

    Lombardo, I., E-mail: ilombardo@lns.infn.it; Agodi, C.; Alba, R.; Amorini, F.; Anzalone, A. [INFN Laboratori Nazionali del Sud (Italy); Auditore, L. [Universita di Messina, and INFN-Gr. Coll. Messina, Dipartimento di Fisica (Italy); Berceanu, I. [Institute for Physics and Nuclear Engineering (Romania); Cardella, G. [INFN, Sezione di Catania (Italy); Cavallaro, S. [INFN Laboratori Nazionali del Sud (Italy); Chatterjee, M. B. [Saha Institute of Nuclear Physics (India); Filippo, E. De [INFN, Sezione di Catania (Italy); Di Pietro, A.; Figuera, P. [INFN Laboratori Nazionali del Sud (Italy); Giuliani, G.; Geraci, E.; Grassi, L. [Dipartimento di Fisica e Astronomia Universita di Catania (Italy); Grzeszczuk, A. [University of Silesia, Institute of Physics (Poland); Han, J. [INFN Laboratori Nazionali del Sud (Italy); La Guidara, E. [INFN, Sezione di Catania (Italy); Lanzalone, G. [INFN Laboratori Nazionali del Sud (Italy); and others

    2011-11-15

    Isospin dependence of dynamical and thermodynamical properties observed in reactions {sup 40}Ca+ {sup 40,48}Ca and {sup 40}Ca + {sup 46}Ti at 25 MeV/nucleon has been studied. We used the CHIMERA multi-detector array. Strong isospin effects are seen in the isotopic distributions of light nuclei and in the competition between different reaction mechanisms in semi-central collisions. We will show also preliminary results obtained in nuclear collision {sup 48}Ca + {sup 48}Ca at 25MeV/nucleon, having very high N/Z value in the entrance channel (N/Z = 1.4). The enhancement of evaporation residue production confirms the strong role played by the N/Z degree of freedom in nuclear dynamics.

  17. Isospin Dependence of Incomplete Fusion Reactions at 25 Mev/a

    Amorini, F; Giuliani, G; Papa, M; Agodi, C; Alba, R; Anzalone, A; Berceanu, I; Cavallaro, S; Chatterjee, M B; Coniglione, R; De Filippo, E; Di Pietro, A; Geraci, E; Grassi, L; Grzeszczuk, A; Figuera, P; La Guidara, E; Lanzalone, G; Neindre, N Le; Lombardo, I; Maiolino, C; Pagano, A; Pirrone, S; Politi, G; Pop, A; Porto, F; Rizzo, F; Russotto, P; Santonocito, D; Sapienza, P; Verde, G

    2008-01-01

    40Ca+40,48Ca,46Ti reactions at 25 MeV/A have been studied using the 4p CHIMERA detector. An isospin effect on the competition between incomplete fusion and dissipative binary reaction mechanisms has been observed. The probability of producing a compound system is observed to be lower in the case of N=Z colliding systems as compared to the case of reactions induced on the more neutron rich 48Ca target. Predictions based on CoMD-II calculations show that the competition between fusion-like and dissipative reactions, for the selected centrality, can strongly constraint the parameterization of symmetry energy and its density dependence in the nuclear equation of state.

  18. Angular momentum projection of cranked Hartree-Fock states: Application to terminating bands in A~44 nuclei

    Zdunczuk, H; Dobaczewski, J; Kosmulski, M

    2007-01-01

    We present the first systematic calculations based on the angular-momentum projection of cranked Slater determinants. We propose the Iy --> I scheme, by which one projects the angular momentum I from the 1D cranked state constrained to the average spin projection of =I. Calculations performed for the rotational band in 46Ti show that the AMP Iy --> I scheme offers a natural mechanism for correcting the cranking moment of inertia at low-spins and shifting the terminating state up by ~2 MeV, in accordance with data. We also apply this scheme to high-spin states near the band termination in A~44 nuclei, and compare results thereof with experimental data, shell-model calculations, and results of the approximate analytical symmetry-restoration method proposed previously.

  19. Zinc isotope fractionation during adsorption on calcite

    Dong, S.; Wasylenki, L. E.

    2013-12-01

    Zinc is an important element as a nutrient in the marine biosphere. However, our understanding of its biogeochemical cycling in the oceans is relatively limited. The Zn stable isotope system holds the promise of providing novel insights, since published Zn isotopic values for various natural samples reveal significant fractionations in the marine environment. Surface seawater, basalts, shales, deep-sea clay sediments, sediment trap material, bulk plankton and zooplankton samples, and eolian dust fall within a tight range (δ66/64Zn from -0.1 to 0.5‰), but modern ferromanganese crusts (δ66/64Zn from 0.5 to 1.2‰), as well as carbonates (δ66/64Zn from 0.3 to 1.4‰), are notably enriched in heavy Zn isotopes [1-4]. In this study we seek to constrain the mechanism by which carbonates are enriched in heavier isotopes. In particular, we have conducted experiments to quantify isotope fractionation during adsorption of Zn onto the surfaces of calcite crystals that are in equilibrium with solution. The adsorption experiments were carried out in a series of small-volume batch reactions in a clean laboratory environment, using high-purity reagents and calcite seed crystals. The calcite was equilibrated with the solution prior to addition of Zn at atmospheric CO2 pressure (i.e., in air) for 5 days until a stable pH of 8.3 was reached. Later, a small aliquot of dissolved ZnCl2 was added such that the solution remained undersaturated with respect to hydrozincite. Experimental duration varied among the replicates from 6 to 144 hours, and then all solids and solutions were separated by filtration, purified by ion exchange chromatography, and analyzed by MC-ICP-MS. Zn adsorbed on calcite is isotopically heavier than in the co-existing solutions, with Δ68/66Zncalcite-solution of approximately 0.3‰. The variation of Δ68/66Zncalcite-solution beyond 24 hours is insignificant, so we infer that isotopic equilibrium is reached by this time. Previous work strongly suggests that a

  20. Study of angular momentum variation due to entrance channel effect in heavy ion fusion reactions

    Kumar, Ajay

    2014-05-01

    A systematic investigation of the properties of hot nuclei may be studied by detecting the evaporated particles. These emissions reflect the behavior of the nucleus at various stages of the deexcitation cascade. When the nucleus is formed by the collision of a heavy nucleus with a light particle, the statistical model has done a good job of predicting the distribution of evaporated particles when reasonable choices were made for the level densities and yrast lines. Comparison to more specific measurements could, of course, provide a more severe test of the model and enable one to identify the deviations from the statistical model as the signature of other effects not included in the model. Some papers have claimed that experimental evaporation spectra from heavy-ion fusion reactions at higher excitation energies and angular momenta are no longer consistent with the predictions of the standard statistical model. In order to confirm this prediction we have employed two systems, a mass-symmetric (31P+45Sc) and a mass-asymmetric channel (12C+64Zn), leading to the same compound nucleus 76Kr* at the excitation energy of 75 MeV. Neutron energy spectra of the asymmetric system (12C+64Zn) at different angles are well described by the statistical model predictions using the normal value of the level density parameter a = A/8 MeV-1. However, in the case of the symmetric system (31P+45Sc), the statistical model interpretation of the data requires the change in the value of a = A/10 MeV-1. The delayed evolution of the compound system in case of the symmetric 31P+45Sc system may lead to the formation of a temperature equilibrated dinuclear complex, which may be responsible for the neutron emission at higher temperature, while the protons and alpha particles are evaporated after neutron emission when the system is sufficiently cooled down and the higher g-values do not contribute in the formation of the compound nucleus for the symmetric entrance channel in case of charged

  1. Calculation and measurement of helium generation and solid transmutations in Cu-Zn-Ni alloys

    Greenwood, L.R.; Oliver, B.M.; Garner, F.A. [Pacific Northwest National Lab., Richland, WA (United States); Muroga, T. [National Inst. of Fusion Science, Nagoya (Japan)

    1998-03-01

    A method was recently proposed by Garner and Greenwood that would allow the separation of the effects of solid and gaseous transmutation for Cu-Zn-Ni alloys. Pure copper produces zinc and nickel during neutron irradiation. {sup 63}Cu transmutes to {sup 64}Ni and {sup 64}Zn, in about a 2-to-1 ratio, and {sup 65}Cu transmutes to {sup 66}Zn. The {sup 64}Zn further transmutes to {sup 65}Zn which has been shown to have a high thermal neutron (n,{alpha}) cross-section. Since a three-step reaction sequence is required for natural copper, the amount of helium produced is much smaller than would be produced for the two-step, well-known {sup 58}Ni (n,{gamma}) {sup 59}Ni (n,{alpha}) reaction sequence. The addition of natural Zn and Ni to copper leads to greatly increased helium production in neutron spectra with a significant thermal component. Using a suitable Cu-Zn-Ni alloy matrix and comparative irradiation of thermal neutron-shielded and unshielded specimens, it should be possible to distinguish the separate influences of the solid and gaseous transmutants. Whereas helium generation rates have been previously measured for natural nickel and copper, they have not been measured for natural Zn or Cu-Ni-Zn alloys. The (N,{alpha}) cross section for {sup 65}Zn was inferred from helium measurements made with natural copper. By comparing helium production in Cu and Cu-Zn alloys, this cross section can be determined more accurately. In the current study, both the solid and helium transmutants were measured for Cu, Cu-5Ni, Cu-3.5Zn and Cu-5Ni-2Zn, irradiated in each of two positions in the HFIR JP-23 test. Highly accurate helium measurements were performed on these materials by isotope dilution mass spectrometry using a facility that was recently moved from Rockwell International to PNNL. It is shown that both the helium and solid transmutants for Cu-zn-Ni alloys can be calculated with reasonable certainty, allowing the development of a transmutation experiment as proposed by

  2. A new method of pure 111In production by proton-induced nuclear reactions with enriched 112Sn

    We aimed at finding out a simple and reliable way of 111In production with the highest radionuclide purity from its grand parent 111Sb and parent 111Sn nuclei, produced by the 112Sn(p, 2n)111Sb and 112Sn(p, pn)111Sn reactions, respectively. The target was a metallic 112Sn sample enriched to 84%. We have measured activation cross sections for seven reactions on an enriched 112Sn sample induced by 23.6 ± 0.8 MeV energy protons. Gamma-ray spectroscopy with high-purity germanium detectors has been used. We also identified the activities of 55Co (T1/2 = 17.5 h) and 60Cu (T1/2 = 23.7 min) in proton beam monitoring Ni foils, induced in the natNi(p,X)55Co and natNi(p,X)60Cu reactions at 22.8 MeV proton energy. The cross sections determined for these reactions are: σ[natNi(p,X)55Co] = 36.6 ±4 mb and σ[natNi(p,X)60Cu] 64.4 ±7 mb. The measured cross sections of reactions on tin isotopes are: σ[112Sn(p,n)112Sb] = 4 ±0.8 mb; σ[112Sn(p,2n)111Sb] = 182 ±26 mb; σ[112Sn(p,pn)111Sn] = 307 ±35 mb; σ[114Sn(p,2n)113Sb] = 442 ±52 mb; σ[117Sn(p,n)117Sb] = 15 ±3 mb; σ[117Sn(p,p)117mSn] = 0.37 ±0.06 mb; σ[115Sn(p,2p)114m2In] = 0.01 ±0.002 mb. Our measurements indicated the expected yield of the 111In production to be 46 MBq/μAh (1.2 mCi/μAh). The contamination of 111In by the undesired nuclide 114m2In was determined and belongs to the smallest ones found in the literature. The measured cross sections were compared with theoretical calculations by two top-level nuclear reaction codes EMPIRE and TALYS. (authors)

  3. Correlation between the fragmentation modes and light charged particles emission in heavy ion collisions

    ZHANG YingXun[1; ZHOU ChengShuang[1,2; CHEN JiXian[1,2; WANG Ning[2; ZHAO Kai[1; LI ZhuXia[1

    2015-01-01

    The correlation between the shape of rapidity distribution of the yield of light charged particles and the fragmentation modes in semi-peripheral collisions for 70Zn+70Zn, 64Zn+64Zn and 64Ni+64Ni at the beam energy of 35 MeV/nucleon is investigated based on ImQMD05 code. Our studies show there is an interplay between the binary, ternary and multi-fragmentation break-up modes. The binary and ternary break-up modes more prefer to emit light charged particles at middle rapidity and give larger values of Rmid compared with the multi-fragmentation break-up mode does. The reduced rapidity distribution for the normalized yields of yield p, d, t, 3He, 4He and 6He and the corresponding values ~ Rmid oI yield can be used to estimate the probability of multi-fragmentation break-up modes. By comparing to experimental data, our results illustrate that ~40% of the collisions events belong to the multi- fragmentation break-up mode for the reactions we studied.

  4. Application of elemental bioimaging using laser ablation ICP-MS in forest pathology: distribution of elements in the bark of Picea sitchensis following wounding

    Siebold, Magdalena [University of Aberdeen, Department of Plant and Soil Science, Institute of Biological and Environmental Sciences, Aberdeen (United Kingdom); University of Natural Resources and Applied Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Forest Entomology, Forest Pathology and Forest Protection, Vienna (Austria); Georg-August University Goettingen, Division of Plant Pathology and Crop Protection, Department of Crop Sciences, Goettingen (Germany); Leidich, Patrick; Bertini, Martina; Feldmann, Joerg [University of Aberdeen, TESLA, Trace Element Speciation Laboratory, Department of Chemistry, Aberdeen (United Kingdom); Deflorio, Giuliana; Woodward, Steve [University of Aberdeen, Department of Plant and Soil Science, Institute of Biological and Environmental Sciences, Aberdeen (United Kingdom); Krupp, Eva M. [University of Aberdeen, TESLA, Trace Element Speciation Laboratory, Department of Chemistry, Aberdeen (United Kingdom); University of Aberdeen, ACES, Aberdeen Centre of Environmental Sustainability, Aberdeen (United Kingdom); Halmschlager, Erhard [University of Natural Resources and Applied Life Sciences Vienna, Department of Forest and Soil Sciences, Institute of Forest Entomology, Forest Pathology and Forest Protection, Vienna (Austria)

    2012-04-15

    Element distribution in the bark of two 20-year-old clones of Picea sitchensis following wounding was studied using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Bark was sampled at 0, 3, and 43 days after wounding and analysed using a focused Nd:YAG laser (266 nm). Intensities of {sup 13} C, {sup 25}Mg, {sup 27}Al, {sup 31}P, {sup 32}S, {sup 39}K, {sup 48}Ca, {sup 55}Mn, {sup 57}Fe, {sup 63}Cu and {sup 64}Zn were measured by ICP-MS to study elemental distribution across the bark samples during the wound repair process. A clear accumulation of Mg, P and K at the boundary zone between the lesion and healthy tissue was detected in the wounded samples and was more distinctive at 43 than at 3 days after treatment. This zone of accumulation mapped onto the position of formation of the ligno-suberised boundary zone and differentiation of the wound periderm. These accumulations suggest major roles for Mg, P and K in the non-specific response of Sitka spruce both to wounding, possibly as co-factors to enzymes and energy utilisation. The LA-ICP-MS method developed in this work proved useful to study spatial element distribution across bark samples and has great potential for applications in other areas of plant pathology research. (orig.)

  5. Application of gas chromatography/mass spectroscopy to the investigation of metabolic pathways of trace elements using stable isotopes as tracers

    Zinc and copper metabolism became easier to study after science provided two research ways: Isotope tracer technique and atomic absorption spectroscopy. Using stable isotopes is advantageous in humans because exposure to radioactivity is avoided and therefore the method can be used safely in infants and pregnant women. We have investigated the bioavailability of zinc in a group of premature infants and one term infant weighing 1 850 to 5 630 g and the copper absorption in a man and an adolescent with M. Wilson (a copper storage disease) and discuss the accurate isotope analysis of human feces in relation to mineral bioavailability studies of premature infants. It is shown that for the determination of bioavailability of zinc and copper, the method of chelate-gas chromatography/mass spectrometry (GC/MS) is valuable for routine application to clinical experiments; the human fecal samples resulting from diet suitably enriched with isotopes 68Zn, 70Zn or 65Cu can be routinely analysed with a precision of about 1% for these stable isotopes. The total zinc in feces was determined by atomic absorption spectroscopy and the 70Zn/64Zn ratio by chelate-GC/MS (EI). We have found different absorption values between 3% to 70% for zinc in a group of different infants including twins, triplets and preterms. The copper uptake was determined to be 79.7% and 49.9%. (orig./RB)

  6. Communication of nuclear data progress No.25 (2001. 6)

    This is the 25th issue of Communication of Nuclear Data Progress (CNDP), in which the achievements in nuclear data field for the last year in China are carried. It includes the measurements of 10B(n, γ)7Li and 64Zn(n,α) 61Ni angular distributions and cross sections, 75As(n,γ) 76As cross section and fission product yields of n + 235,238U; theoretical calculations of n + 23Na, 93,95Nb, 99Tc, 99-105Ru, 132,134-138Ba, 133-135,137Cs, 136,138,140,142NatCe, 142-148,150Nd, 175,176NatLu, 174,176-180NatHf; evaluations of reference fission yield data and n + 93,95Nb, 99,100Ru, 121,123Sb, 127,135I and 241,242Pu complete data; method to set up file 6 in neutron data library of light nuclei, Kerma factor calculation, a code for automatically searching optimal optical potential parameters below 300 MeV, internal conversion electrons data calculation, a code for composition of a nuclear data file of natural element from its isotope files; and the developments of CWIMS code and its 69-group library. Also the activities and cooperation on nuclear data in China are summarized

  7. Sensitivity of N/Z ratio in projectile break-up of isobaric systems

    De Filippo E.

    2016-01-01

    Full Text Available The binary break-up of projectile-like fragments in non central heavy-ion collisions follows different decay patterns, from equilibrated emission towards dynamical (prompt fission. Recently, comparing two systems with different N/Z in the entrance channel, it has been shown that the dynamical emission cross-section is enhanced for the most neutron rich system while the statistical emission cross-section is independent from the isotopic composition. In order to understand this dependence and disentangle it from the initial size of the nuclei, we have studied the two isobaric systems 124Xe+64 Zn and 124Xe+64 Ni at 35 A MeV (InKiIsSy experiment, in comparison with the previous studied reactions (124Sn +64 Ni and 112Sn +58 Ni at the same bombarding energy. We present the first results evidencing a striking similar effect in the dynamical decay as a function of the N/Z of the target for equal size systems.

  8. Application of elemental bioimaging using laser ablation ICP-MS in forest pathology: distribution of elements in the bark of Picea sitchensis following wounding

    Element distribution in the bark of two 20-year-old clones of Picea sitchensis following wounding was studied using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Bark was sampled at 0, 3, and 43 days after wounding and analysed using a focused Nd:YAG laser (266 nm). Intensities of 13 C, 25Mg, 27Al, 31P, 32S, 39K, 48Ca, 55Mn, 57Fe, 63Cu and 64Zn were measured by ICP-MS to study elemental distribution across the bark samples during the wound repair process. A clear accumulation of Mg, P and K at the boundary zone between the lesion and healthy tissue was detected in the wounded samples and was more distinctive at 43 than at 3 days after treatment. This zone of accumulation mapped onto the position of formation of the ligno-suberised boundary zone and differentiation of the wound periderm. These accumulations suggest major roles for Mg, P and K in the non-specific response of Sitka spruce both to wounding, possibly as co-factors to enzymes and energy utilisation. The LA-ICP-MS method developed in this work proved useful to study spatial element distribution across bark samples and has great potential for applications in other areas of plant pathology research. (orig.)

  9. Preparation of [61Cu]-2-acetylpyridine thiosemicarbazone complex as a possible PET tracer for malignancies

    Due to the interesting anti-proliferative properties of copper-thiosemicarbazone complexes, the production of a 61Cu-labeled thiosemicarbazone, i.e. 2-acetylpyridine thiosemicarbazone (APTS) was investigated. Copper-61 (T1/2=3.33h) was produced via the 64Zn(p,α)61Cu nuclear reaction using a natural zinc target irradiated with 22MeV protons for 500μAh. The 61Cu was separated from the irradiated target material by a two-step method and converted to acetate; this yielded a final activity of 222GBq (6.0Ci), with a radiochemical yield of >95%. The 61Cu-acetate was mixed with 2-acetylpyridine thiosemicarbazone for 30min at room temperature to yield [61Cu]APTS with a radiochemical yield of more than 80%. Colorimetric methods showed that residual chemical impurities in the product were below the accepted limits. Radio thin layer chromatography (RTLC) showed a radiochemical purity of more than 99% after C18 column chromatography. A specific activity of about 370-740MBq/mmol (10-20Ci/mmol) was obtained. The stability of the final product was checked in the absence and presence of human serum at 37oC for up to 3h. The partition coefficient of the final complex was also determined

  10. Preparation of [{sup 61}Cu]-2-acetylpyridine thiosemicarbazone complex as a possible PET tracer for malignancies

    Jalilian, A.R. [Cyclotron and Nuclear Medicine Department, Nuclear Research Center for Agriculture and Medicine (NRCAM), Atomic Energy Organization of Iran, Moazzen Boulevard, Rajaeeshahr, P.O. Box 31485-498 Karaj (Iran, Islamic Republic of)]. E-mail: ajalilian@nrcam.org; Rowshanfarzad, P. [Cyclotron and Nuclear Medicine Department, Nuclear Research Center for Agriculture and Medicine (NRCAM), Atomic Energy Organization of Iran, Moazzen Boulevard, Rajaeeshahr, P.O. Box 31485-498 Karaj (Iran, Islamic Republic of); Sabet, M. [SSDL and Health Physics Department, Nuclear Research Center for Agriculture and Medicine (NRCAM), Atomic Energy Organization of Iran, Moazzen Boulevard, Rajaeeshahr, P.O. Box 31485-498 Karaj, Iran. (Iran); Shafiee, A. [Faculty of Pharmacy and Pharmaceutical Sciences Research center, Tehran University of Medical Sciences, P.O. Box 14155-6451 Tehran (Iran, Islamic Republic of)

    2006-03-15

    Due to the interesting anti-proliferative properties of copper-thiosemicarbazone complexes, the production of a {sup 61}Cu-labeled thiosemicarbazone, i.e. 2-acetylpyridine thiosemicarbazone (APTS) was investigated. Copper-61 (T{sub 1/2}=3.33h) was produced via the {sup 64}Zn(p,{alpha}){sup 61}Cu nuclear reaction using a natural zinc target irradiated with 22MeV protons for 500{mu}Ah. The {sup 61}Cu was separated from the irradiated target material by a two-step method and converted to acetate; this yielded a final activity of 222GBq (6.0Ci), with a radiochemical yield of >95%. The {sup 61}Cu-acetate was mixed with 2-acetylpyridine thiosemicarbazone for 30min at room temperature to yield [{sup 61}Cu]APTS with a radiochemical yield of more than 80%. Colorimetric methods showed that residual chemical impurities in the product were below the accepted limits. Radio thin layer chromatography (RTLC) showed a radiochemical purity of more than 99% after C{sub 18} column chromatography. A specific activity of about 370-740MBq/mmol (10-20Ci/mmol) was obtained. The stability of the final product was checked in the absence and presence of human serum at 37{sup o}C for up to 3h. The partition coefficient of the final complex was also determined.

  11. Abundance and Impact of Doubly Charged Polyatomic Argon Interferences in ICPMS Spectra.

    Hattendorf, Bodo; Gusmini, Bianca; Dorta, Ladina; Houk, Robert S; Günther, Detlef

    2016-07-19

    Doubly charged molecular ions of alkaline earth metals and argon could be identified as spectral interferences in an inductively coupled plasma mass spectrometer. These molecular ions were found to occur at abundances reaching about 10(-4) relative to the alkaline earth atomic ion abundances. They can thus substantially affect ultratrace analyses and, when present at similar concentration as the analyte elements, also isotope ratio measurements. For the case of Cu and Zn isotope ratio analyses, the same mass concentration of Sr was found to alter the measured (63)Cu/(65)Cu and (64)Zn/(66)Zn isotope ratios by -0.036‰ to -0.95‰ due to SrAr(2+), appearing at m/Q 63 and 64. BaAr(2+) can affect Sr isotope analyses, MgAr(2+) may impair S isotope ratio measurements, while CaAr(2+) may cause interference to Ca(+) isotopes. The abundances of the doubly charged molecular ions were higher than those of the corresponding singly charged species, which is in accordance with their generally higher bond dissociation energies. The relative abundances were found to depend significantly on the inductively coupled plasma (ICP) operating conditions and generally increase with increasing carrier gas flow rates or lower gas temperature of the ICP. They also increase by about an order of magnitude when a desolvated aerosol is introduced to the ICP. PMID:27306032

  12. quality control of some radiopharmaceuticals

    copper-67 is one of the most useful radionuclide for radioimmunotherapy. its physical half-life (2.58 d) is appropriate for the residence time of a typical antibody on a tumor cells. the high-energy electrons (β- particles ) emitted by 67Cu cause toxic chemical reactions within target tumor cells located with a few millimeters of the radionuclide the chelation of copper-67 with a bifunctional chelator (BFC) such as a cyclic DTPA anhydride may be useful in diagnostic and radiotherapeutic studies using nuclear medicine instrumentations. this work describes the production of carrier-free radioactive copper from natural zinc metal as target material irradiated at ETRR-2 and ETRR-1 research reactors. radioactive copper-64 and 67 were prepared according to the fast neutron reaction 64Zn (n,p) 64Cu and 67Zn (n,p) 67Cu. the zine chloride radiotracer in 8 M HCl acid solution was loaded onto the anion exchanger resin (Dowex 1 x 8, Cl-- ion form, 200-400 mesh, i.d. 0.9 x 10 cm) at flow rate 1 ml/min

  13. Radiochemical measurement of neutron-spectrum averaged cross sections for the formation of {sup 64}Cu and {sup 67}Cu via the (n,p) reaction at a TRIGA Mark-II reactor. Feasibility of simultaneous production of the theragnostic pair {sup 64}Cu/{sup 67}Cu

    Uddin, M. Shuza; Hossain, Syed Mohammod [Atomic Energy Research Establishment, Dhaka (Bangladesh). Inst. of Nuclear Science and Technology; Rumman-uz-Zaman, M. [Atomic Energy Research Establishment, Dhaka (Bangladesh). Inst. of Nuclear Science and Technology; Dhaka Univ. (Bangladesh). Dept. of Applied Chemistry and Chemical Engineering; Qaim, Syed M. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Neurowissenschaften und Medizin (INM-5) - Nuklearchemie

    2014-09-01

    Integral cross sections of the {sup 64}Zn(n,p){sup 64}Cu and {sup 67}Zn(n,p){sup 67}Cu reactions were measured for the fast neutron spectrum of TRIGA Mark-II reactor at Savar, Dhaka, Bangladesh. A clean radiochemical separation was performed to isolate the copper radionuclides from the target element zinc. The radioactivities produced in the irradiation were measured by HPGe γ-ray spectroscopy. The neutron flux over the energy range 0.5-20 MeV was determined using the {sup 58}Ni(n,p){sup 58}Co monitor reaction. The measured results amount to 28.9 ± 2.0 mb and 0.84 ± 0.07 mb for the formation of {sup 64}Cu and {sup 67}Cu, respectively. These values are slightly lower than the respective values for a pure fission spectrum. The present results were compared with data calculated using the neutron spectral distribution and the recently critically analysed excitation function of each reaction given in the literature. The good agreement validates the reliability of those excitation functions. The feasibility of simultaneous production of {sup 64}Cu and {sup 67}Cu with fast neutrons is discussed. (orig.)

  14. Study of the reactions (nsub(th),α) (nsub(th),γα) and (nsub(th),p) among medium and heavy nuclei

    A systematic investigation of alpha particle and proton emission following capture of thermal neutron has been performed at the ILL'S high flux reactor. The (nsub(th),α) reaction could be investigated among most of the stable nuclei and several radioactive one. Experimental results are presented on 33S, 37Ar, 40K, 59Ni, 64Zn, 65Zn, 67Zn, 77Se, 93Mo, 95Mo, 123Te, 143Nd, 145Nd, 147Sm, 149Sm, 151Eu, 155Gd, 167Er, 177Hf, 238U. A method has been proposed for calculation of the (n,α) cross section. This method has been tested on all the experimental results. Fluctuation of experimental values compared to theoretical one are those predicted by the statistical model. Moreover the very rare (nsub(th),p) reaction could be observed on the 35Cl, 37Ar, 40K, 59Ni, 76Br, 84Rb nuclei and the (n,γ-α) reaction has been investigated with 40K, 143Nd and 149Sm samples

  15. Customization of ENDF/B-VI and JENDL3.2 basic data for MCNP calculation and measurements on neutron cross section at INST, AERE, Savar

    Bhuiyan, S.I.; Molla, N.I.; Chakrobortty, T.K.; Huda, M.Q.; Mondal, M.A.W. [Institute of Nuclear Science and Technology (INST), Atomic Energy Research Establishment, Savar, Dhaka (Bangladesh)

    2000-03-01

    The NJOY94.10{sup +}, a version of NJOY, has been installed in a VAX computer under Open VMS operating system. ENDF/B-VI, latest release of ENDF data, has been also implemented in the same system. A data library has been processed using the modules RECONR, BROADR and ACER of NJOY code. MCNP4B2 computer code has been used to validate the prepared data library for some benchmark experiments. The results obtained have been found to be in good agreement with the experimental results. Excitation function have been measured for {sup 81}Br(n,alpha){sup 78}As, {sup 79}Br(n,alpha){sup 76}As, {sup 73}Ge(n,p){sup 73}Ga, {sup 72}Ge(n,p){sup 72}Ga, {sup 64}Zn(n,p){sup 64}Cu, {sup 68}Zn(n,alpha){sup 65}Ni, and {sup 70}Zn(n,2n){sup 69m}Zn reactions in the neutron energy range 13.57-14.71 MeV via Activation technique. (author)

  16. Thermal properties of a rotating nucleus in a fluctuating mean-field approach

    The static-path approximation to the path integral representation of partition function provides a natural microscopic basis to deal with thermal fluctuations around mean-field configurations. Using this approach for a one-dimensional cranking hamiltonian with quadrupole-quadrupole interaction term we have studied a few properties like energy, level-density, level-density parameter (a) and moment of inertia as a function of temperature and spin for 64Zn taking it as an illustrative example. We have also investigated the effects of variation in interaction strength on the level density and the parameter a as a function of temperature. The moment of inertia, I, versus rotational frequency, ω, plot shows a sudden rise in the value of I due to the rotation alignment of Og9/2 orbitals at ω ∼ 1.0 MeV for a small temperature T ∼ 0.5 MeV. At high T ∼ 2.0 MeV about 40-45% of each angular momentum is generated by the alignment of Og9/2 orbitals with an interesting result that at ω ∼ 1.0 MeV and spin J ∼ 16 the moment of inertia has almost a constant, temperature-independent value. (orig.)

  17. An Analysis of Heavy-Ion Elastic Scattering Processes Using Numerical Model Based on the Partial Wave Parameterised S-Matrix with Regge Pole Factor

    Badran, R. I.; Al-Lehyani, I. H.

    2016-06-01

    Analyses of the angular distributions in the elastic scattering processes of 9, 10, 11Be by the target nucleus 64Zn at the laboratory energies of 27.95 MeV, and 4, 6, 8He by the target nucleus 208Pb at the laboratory energy of 22 MeV are performed. These analyses rely on a numerical model based on a parameterised scattering matrix (S-matrix) derived from Frahn and Venter. They confirm the absence of the Coulomb rainbow peak in angular distributions of elastic scattering in collisions of halo nuclei at energies around the Coulomb barrier. The correlation between the total reaction cross section and the halo structure for each scattering that involves a halo nucleus is discussed, and values of the total reaction cross section are found comparable with those of others. The diffractive features of the systems 16, 18O + 19F at specific laboratory energies are examined, and the effect of exchanging the projectile and target nuclei at such energies on these features are inspected. The incorporation of the Regge pole factor into the parameterised S-matrix calculations, which is found important in some cases, is employed in order to account for the oscillatory structure (if available) at backward angles. The theoretical results are found reasonable, reproducing the general pattern of the data. The trend of the extracted parameters meets the requirements proposed by the adopted models.

  18. SIMS and RBS Investigation of Zn Implanted Si

    We present results of secondary ion mass-spectrometry and Rutherford backscattering spectroscopy of the Zn implantation profile in the damaged layer of a n-type Cz-Si(100) substrate, as well as the profile change during annealing. Si wafers were implanted with 64Zn+ ions at energy of 100 keV and ion dose of 2x1014cm-2. They were then subsequently annealed at 400 deg. C for 60 min and 700 deg. C for 10 min. Analysis of experimental data shows that in the as-implanted sample on a silicon surface a damage gauzy amorphous layer with thickness about 80nm was created, located inside the substrate at the ion-implantation depth. After two annealing steps the defects were completely annealed out. From the Zn depth profiles we observe that during annealing the Zn concentration decreases and the Zn peak concentration moves to the wafer surface. The Zn concentration maximum exceeds the solubility limit of Zn in Si, suggesting decomposition of Zn solid solution in Si and Zn precipitation.

  19. Reactions induced by 11Be beam at Rex-Isolde

    Jeppesen H.

    2011-10-01

    Full Text Available The collision induced by the three Beryllium isotopes, 9,10,11Be, on a 64Zn target were investigated at Ec.m. ≈ 1.4 the Coulomb barrier. The experiments with the radioactive 10,11Be beams were performed at the Rex-Isolde facility at CERN. In the case of 9,10Be, elastic scattering angular distributions were measured whereas, in the 11Be case, the quasielastic scattering angular distribution was obtained. A strong damping of the quasielastic cross-section was observed in the 11Be case, in the angular range around the Coulomb-nuclear interference peak. In this latter case a large total-reaction cross-section is found. Such a cross-section is more than a factor of two larger than the ones extracted in the reactions induced by the non-halo Beryllium isotopes. A large contribution to the total-reaction cross-section in the 11Be case could be attributed to transfer and/or break-up events.

  20. Probing the nuclear multipole response with intermediate energy heavy ions

    Intermediate energy (∼100 MeV/nucleon) heavy ion inelastic scattering excites low multipolarity giant resonances (GR) with very large cross sections (∼barns/sr for states which exhaust a large fraction of the relevant energy-weighted sum rule), and excites the continuum underlying the GR very weakly compared to light hadronic probes. These two features, combined with the fact that high resolution magnetic spectrometers are available at intermediate-energy heavy ion facilities, mean that heavy ion scattering has enormous promise for use in DR decay studies, and for isolating and studying weak states lying above the GDR. The author illustrates some of this promise with the results of experiments employing inelastic scattering of 17O, 36Ar, 86Kr, and 64Zn at energies ranging from 60 to 95 MeV/nucleon. These experiments were carried out at GANIL, and employed a high resolution magnetic spectrograph to detect the inelastically scattered particle, a large array of BaF2 detectors and a plastic open-quotes forward wallclose quotes hodoscope to study decay products. Results of studies of the decay of the GDR and the investigation of exotic strength above the GDR, including the identification and study of two-phonon strength, are discussed. The work involves scientists from ORNL, MSU, GANIL, KVI, GSI, Giessen, and Valencia

  1. Competition between collective and single particle excitations in nuclear structure description

    The microscopic description of the quadrupole collective dynamics in even krypton isotopes is presented. A microscopic calculation of Bohr's collective Hamiltonian is used to describe the collective motion in 76Kr. A single-particle basis calculated in a deformed Woods-Saxon potential leads to the potential energy surface obtained by the Strutinsky renormalization procedure, and to the inertial functions determined in the cranking model approximation. The collective Schroedinger equation is solved numerically to analyse the low-energy, even parity states in 76Kr. A good agreement between experiment and theory is obtained without specifically adjusting any parameter in the model for this nucleus. Some results regarding statical and dynamical characteristics of sup(74,78,80)Kr isotopes are also presented. The asymmetric rotor model with admixture of two quasiparticles is used to describe the sup(66,68,70)Ge and the sup(64,66)Zn isotopes. The interplay of collective and single particle motions is further investigated by magnetic moment measurements using the method of integral angular correlations perturbed by recoil into gas. The results involve g-factor measurements for 166Ho, 68Ge, 64Zn, 66Zn and 68Ga nuclei. Finally, a discussion of further possible improvements and more general developments of the problems under investigation is given. (author)

  2. The measurement of the isotope ratios and concentrations of zinc by thermal ionization mass spectrometry using double isotope dilution

    The isotope ratios and concentrations of zinc are measured by silicagel-thermal ionization mass spectrometry using the double isotope spikers. The double isotope spikers (70Zn and 67Zn-enriched isotopes) are used to correct the isotope mass fractionation for the zinc isotope ratios, and to certify the zinc concentrations in the unknown samples. The zinc concentrations of these double isotope spikers are surveyed by a spiker made of pure (99.99%) natural zinc metal powder. The correcting factors (fa, ft and fn) of the zinc isotope ratios in the spiked mixture, spike and unspiked samples for the isotope mass fractionation, and the spike-to-unspiked ratios (Xr) of the zinc isotope r in the spiked mixture samples can be obtained to solve the matrix equations by numerical approximation. The natural zinc isotope ratios are: 64Zn/67Zn = 11.8498, 66Zn/67Zn = 6.7977, 68Zn/67Zn = 4.5730 and 70Zn/67Zn = 0.1520. The uncertainties determined of the isotope ratios and concentrations of zinc are +- 0.16% and +-0.31%, respectively

  3. Discussion on the Key Factors of Abundance Ratios About Zn Isotope Measurement

    The application of Zn isotope analysis is well known in geochemistry and diet study. An inter-lab comparison of five samples with isotopic ratio covering from 0.02 to 15.00 was organized in order to develop measurement ability and keep consistency of the results of isotopic ratios measurement among the participants. Multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) and multi-collector thermal ionization mass spectrometry (MC-TIMS) were used. For MC-ICP-MS, blank-corrected and blank-no corrected results were submitted. For MC-TIMS, total evaporation method (TE) was applied to the samples while a certified reference material IRMM3702 was analyzed together. All the results showed that the uncertainties were 1.29%-0.03% for 64Zn/66Zn, and the uncertainty was obviously relative to isotopic abundances. The blank-corrected and blank-no corrected and the influence of blank and non-linear of K factor of mass discrimination for MC-ICP-MS were convinced of contributing to the unsatisfied uncertainties. (authors)

  4. Utilization and operating experience of the 250 kw TRIGA Mark II research reactor in Ljubljana

    In its 35th year, the TRIGA Mark II 250 kW pulsing research reactor in Ljubljana is continuing its busy operation. With the maximum neutron flux in the central thimble of 10 13 n/cm 2 sec and many sample radiation positions the reactor has been used to perform many experiments in the following fields: solid state physics (elastic and inelastic neutron scattering), neutron dosimetry, neutron radiography, reactor physics including burn up measurements and calculations, boron neutron capture therapy and neutron activation analysis which represents one of the major usage of our reactor. Besides these, applied research around the reactor has been conducted, such as doping of silicon monocrystals, a routine production of various radioactive isotopes for industry ( 60Co, 64Zn, 24Na, 82Br) and medical use ( 18F, 99m Tc, etc.) and other activities. During the past decade the reactor was almost completely reconstructed (new grid plates, the control mechanisms and the control unit, modification of the spent fuel storage pool, etc). The main novelty in the reactor physics and operation features of the reactor was the installation of a pulse rod, therefore the reactor can be operated in a pulse mode. After reconstruction, the core was loaded with fresh 20% enriched fuel elements. In 1999 all spent fuel elements were shipped to the USA. (author)

  5. Experimental Guidance of ISB Corrections via Direct Nuclear Reactions

    Leach, K. G.; Garrett, P. E.; Ball, G. C.; Bangay, J. C.; Bianco, L.; Demand, G. A.; Faestermann, T.; Finlay, P.; Green, K. L.; Hertenberger, R.; Kriicken, R.; Phillips, A. A.; Rand, E. T.; Sumithrarachchi, C. S.; Svensson, C. E.; Towner, I. S.; Triambak, S.; Wirth, H.-F.; Wong, J.

    2011-09-01

    The most recent isospin-symmetry-breaking corrections, δc, of Towner and Hardy for superallowed Fermi β-decay transitions, have included the opening of specific core orbitals. This change has resulted in significant deviations in some of the δc factors from their previous calculations, and an improved agreement of the individual corrected Script Ft values with the overall world average of the 13 most precise cases. While this is consistent with the conserved-vector-current (CVC) hypothesis of the Standard Model, these new calculations must be thoroughly tested, and guidance must be given for the improvement of calculations for the upper-pf shell nuclei. Using the (d,t) reaction mechanism to probe the single neutron wavefunction overlap, information regarding the relevant shell-model configurations needed in the calculation can be determined. An experiment was therefore performed with a 22 MeV polarized deuterium beam from the MP tandem Van de Graaff accelerator in Munich, Germany. Using the Q3D magnetic spectrograph, and a cathode-strip focal-plane detector, outgoing tritons were analyzed at 9 angles between 10° and 60°, up to an excitation energy of 4.8 MeV. This proceeding reports the motivational and experimental details for the 64Zn(d,t)63Zn transfer work presented.

  6. Average neutron detection efficiency for DEMON detectors

    The neutron detection efficiency of a DEMON detector, averaged over the whole volume, was calculated using GEANT and applied to determine neutron multiplicities in an intermediate heavy ion reaction. When a neutron source is set at a distance of about 1 m from the front surface of the detector, the average efficiency, ϵav, is found to be significantly lower (20–30%) than the efficiency measured at the center of the detector, ϵ0. In the GEANT simulation the ratio R=ϵav/ϵ0 was calculated as a function of neutron energy. The experimental central efficiency multiplied by R was then used to determine the average efficiency. The results were applied to a study of the 64Zn+112Sn reaction at 40 A MeV which employed 16 DEMON detectors. The neutron multiplicity was extracted using a moving source fit. The derived multiplicities are compared well with those determined using the neutron ball in the NIMROD detector array in a separate experiment. Both are in good agreement with multiplicities predicted by a transport model calculation using an antisymmetric molecular dynamics (AMD) model code

  7. Zinc isotope fractionation during magmatic differentiation and the isotopic composition of the bulk Earth

    Chen, Heng; Savage, Paul S.; Teng, Fang-Zehn; Helz, Rosalind T.; Moynier, Frédéric

    2013-01-01

    he zinc stable isotope system has been successfully applied to many and varied fields in geochemistry, but to date it is still not completely clear how this isotope system is affected by igneous processes. In order to evaluate the potential application of Zn isotopes as a proxy for planetary differentiation and volatile history, it is important to constrain the magnitude of Zn isotopic fractionation induced by magmatic differentiation. In this study we present high-precision Zn isotope analyses of two sets of chemically diverse, cogenetic samples from Kilauea Iki lava lake, Hawaii, and Hekla volcano, Iceland, which both show clear evidence of having undergone variable and significant degrees of magmatic differentiation. The Kilauea Iki samples display small but resolvable variations in Zn isotope composition (0.26‰66Zn66Zn defined as the per mille deviation of a sample's 66Zn/64Zn compositional ratio from the JMC-Lyon standard), with the most differentiated lithologies exhibiting more positive δ66Zn values. This fractionation is likely a result of the crystallization of olivine and/or Fe–Ti oxides, which can both host Zn in their crystal structures. Samples from Hekla have a similar range of isotopic variation (0.22‰66Zn66Zn=0.28±0.05‰ (2s.d.).

  8. Measurement of 233U fission spectrum-averaged cross sections for some threshold reactions

    The 233U fission spectrum-averaged cross sections for twelve threshold reactions were measured relative to the average cross section of 0.688 ± 0.040 mb for the 27Al(n,α)24Na reaction. The reference value was obtained by calculation using the energy dependent cross section in the Japanese Evaluated Nuclear Data Library (JENDL) Dosimetry File and the Watt-type fission spectrum in ENDF/B-VI. General agreement was seen between the measured and the calculated fission-spectrum averaged cross sections. However, there exist discrepancies of more than 10% between the measured and the calculated average cross sections for the 24Mg(n,p)24Na, 47Ti(n,p)47Sc, and 64Zn(n,p)64Cu reactions. The tendencies in the calculated-to-measured ratios are similar to those for 235U fission spectrum-averaged cross sections the authors previously measured. The measured average cross sections were also applied for the spectrum adjustment of the 233U fission neutrons using the Neutron Unfolding Package Code (NEUPAC). The adjusted spectrum is close to the Watt-type fission spectrum of 233U within the uncertainties of the obtained spectrum, although there exist some fluctuations in the ratio spectrum of the adjusted to the Watt-type

  9. Production of 61Cu by the natZn(p,α) reaction. Improved separation and specific activity determination by titration with three chelators

    The cyclotron-based production of positronemitting 61Cu using the (p,a) reaction at 11.7 MeV was investigated starting from natural-zinc (natZn) and enriched 64Zn-foil targets, as well as its subsequent purification. For natZn, a combination of three resins were assessed to separate 61Cu from contaminating 66,67,68Ga and natZn. The specific activity of the purified 61Cu determined using ICPMS analysis ranged from 143.3 ± 14.3(SD) to 506.2 ± 50.6 MBq/lg while the titration method using p-SCN-Bn-DOTA, p-SCN-Bn-NOTA and diamsar gave variable results (4.7 ± 0.2-412.5 ± 15.3 MBq/μg), with diamsar lying closest to the ICP-MS values. Results suggest that the p-SCN-Bn-DOTA and p-SCN-Bn-NOTA titration methods are significantly affected by the presence of trace-metal contaminants. (author)

  10. A search for various double beta decay modes of Cd, Te, and Zn isotopes

    Various double beta decay modes of Cd, Zn, and Te isotopes are explored with the help of CdTe and CdZnTe semiconductor detectors. The data set is splitted in an energy range below 1 MeV having a statistics of 134.5 g d and one above 1 MeV resulting in 532 g d. No signals were observed in all channels under investigation. New improved limits for the neutrinoless double beta decay of 70Zn of T1/2>1.3x1016 yrs (90% CL), the longest standing limit of all double beta isotopes, and 0νβ+EC of 120Te of T1/2>2.2x1016 yrs (90% CL) are given. For the first time a limit on the half-life of the 2νECEC of 120Te of T1/2>9.4x1015 yrs (90% CL) is obtained. In addition, limits on 2νECEC for ground state transitions of 106Cd, 108Cd, and 64Zn are improved. The obtained results even under rough background conditions show the reliability of CdTe semiconductor detectors for rare nuclear decay searches

  11. Investigation of dynamics of fusion reactions through cross-section and spin distribution measurements

    The CN populated at high excitation energy and angular momentum in fusion reactions can undergo decay through fission or emission of different light particles (α-particles, neutrons and protons). The statistical model has been extensively used to explain the evaporation spectra of these light particles and to extract important information about the properties of the CN. However, many of the evaporation studies show anomalous results from the statistical model predictions, for the mass symmetric systems. With this motivation we have performed the ER-gated spin distribution and the cross-section measurements for two systems 16O + 64Zn (mass asymmetric) and 32S + 48Ti (mass symmetric) populating the same CN (80Sr) for which the evaporation spectra studies have reported the existence of deviations for the symmetric system. Present measurements have been performed using 15 UD Pelletron accelerator and Heavy Ion Reaction Analyzer (HIRA) facility at Inter University Accelerator Centre (IUAC), New Delhi. The details of these measurements and analysis procedure have been described elsewhere

  12. One or two step processes in one or two proton transfer reactions induced by heavy ions

    The one-proton and two-proton transfer reactions induced by 12C and 16O ion beams in the respective 5+ and 6+ charge states (at 48MeV and 56MeV respectively) were experimentally studied with 62Ni targets. A simultaneous analysis of elastic and inelastic scattering gave the precise characteristics of the optical potential (surface transparency). The DWBA formalism reproduces well the general shapes of angular distributions when the optical potential range is increased in the exit channel (decrease in the Coulomb barrier forward shift of the angular distribution). As for one-proton transfer, the DWBA calculation gives spectroscopic factors in good agreement with the light ion experimental data, in condition that an exact calculation is effected with a finite range potential (recoil). As for two-proton transfer, a DWBA calculation subestimates the experimental cross sections. A more complete calculation of the form factor including the relative motions of both protons and sequential transfers is more valuable. The angular distributions at forward angles are imperfectly reproduced by a DWBA calculation, two-step processes involving a core excitation must be taken into account: projectile excitation in the reaction 62Ni(12C,11B)63Cu or target excitation and residual nucleus excitation in the reaction 62Ni(16O,14C)64Zn

  13. Study of high-fluence titanium implantation into AISI M2 steel by 48Ti isotopic tracing

    AISI M2 steel was implanted with titanium ions of 110 keV incident energy at room temperature. Fluences were varied from 1 to 4x1017 Ti cm-2. The 48Ti(p, γ)49V resonant nuclear reaction at 1362 keV was used to determine selectively the 48Ti distribution profiles. The γ-rays of 7.936 MeV energy and the related escape peaks were identified and used to quantify the 1362 keV resonance yield. In order to understand the mechanisms taking place during titanium implantation, a high Ti fluence was implanted in several steps made up of, first, a 101748Ti cm-2 dose, followed by several successive 101746Ti cm-2 doses. Thus the evolution of the initially implanted 48Ti distribution was followed as the 46Ti dose increased. On the basis of the experimental results, a primary recoil mixing based model is proposed. The agreement obtained between experimental and theoretical mixing rates suggests that the primary recoil mixing process and the sputtering effect are the most important physical mechanisms during high-fluence Ti implantation into steels. (orig.)

  14. Comparison of the charge distributions of the titanium isotopes

    Measurements have been made of the elastic electron scattering from the three even isotopes of titanium, Ti46, Ti48, and Ti50, with the objective of determining the differences in their ground state charge distributions. The experiment measures the ratios of the elastic cross sections of the three isotopes, thereby eliminating many of the uncertainties peculiar to an absolute cross section measurement. The experiment was done at the NBS Linac in Gaithersburg, Maryland. Theoretical calculations using a partial wave elastic scattering program, showed that the ratios of cross sections arising from scattering from two slightly different Fermi type 2 parameter charge distributions, depended strongly on the differences in the parameter describing the charge distribution, but only weakly on the actual values of these parameters. These ratio curves, considered as a function of momentum transfer, achieved their extreme values at momenta transfer near 1.0 F-1, which is near the point where the Born approximation form factor goes to zero. Therefore, ratios of cross sections were measured at momenta transfer ranging from .55 to 1.1 F-1; by holding the scattering angle fixed at 127.50 and varying the incident beam energy from 60 to 123 MeV. 43 refs., 45 figs., 9 tabs

  15. Synthesis and structural and thermodynamical characterization of hollandite type material intended for the specific containment of cesium; Synthese et caracterisation de ceramiques de type hollandite destinees au conditionnement specifique du cecium

    Leinekugel-Le-Cocq-Errien, A.Y

    2005-09-15

    This thesis deals with the characterization of the Ba{sub 1}Cs{sub 0.28}Fe{sub 0.82}Al{sub 1.46}Ti{sub 5.72}O{sub 16} hollandite envisaged for Cs containment. Techniques used are essentially classical powder XRD or synchrotron radiation at the absorption threshold of Ba and Cs, TEM and high-temperature calorimetry. Two syntheses have been studied: an alcoxide route and a dry route. After sintering, both routes lead to an incommensurate modulated tetragonal hollandite structure (space group: I4/m(00{gamma})00) with a modulation vector distribution. Before sintering, the material obtained by the alcoxide route is composed of three phases: a tetragonal hollandite like above, a monoclinic Ba-free hollandite and a weak-coherence-length phase containing only Ba. On contrary, the dry route already leads to the tetragonal hollandite at this step of the synthesis. High temperature oxide melt solution calorimetry was used to derive standard enthalpy of formation of hollandite to deduce its free enthalpy of formation. (author)

  16. Probing the systematics for low energy incomplete fusion with universal fusion function model

    In the recent years, a renewed interest has emerged, in the study of heavy ion (HI) reactions to investigate the effects of breakup and fusion processes at energies around the Coulomb barrier. In HI reactions the complete fusion (CF) takes place when all the nucleons of the projectile and target nuclei lose their identity to form a single complex system followed by equilibration of the compound system. On the other hand, incomplete fusion (ICF) occurs, when only a part of projectile fuses with the target nucleus and remaining part escapes with nearly incident beam velocity. In order to explore the dynamics of HI reactions, a number of studies has been done within the framework of entrance channel parameters with weakly as well as strongly bound projectiles. In the present work, an attempt has been made to study the target dependence on experimentally modified fusion function as suggested by Canto et al.. The experimental data from the experiment performed at IUAC, New Delhi for the 12C projectile on 159Tb target along with 12C+46Ti, 12C+48Ti, 12C+50Ti from the available literature has been renormalized within the framework of recently proposed Universal Fusion Function (UFF) approach

  17. Response of unirradiated and neutron-irradiated vanadium alloys to Charpy-impact loading

    The ductile-brittle transition temperature (DBTT) was determined by Charpy-impact impact tests for dehydrogenated (<30 appm H) and hydrogenated (400--1200 appm H) V-7.2Cr-14.5Ti, V-9.9Cr-9.2Ti, V-13.5Cr-5.2Ti, V-17.7Ti, V-9.2Cr-4.9Ti, V-9.0Cr-3.2Fe-1.2Zr, V-3.1Ti-0.5Si, V-4.1Cr-4.3Ti, V-4.6Ti, and V-2.5Ti-1.0Si alloys. The DBTT was also determined for the V-13.5Cr-5.2Ti, V-9.2Cr-4.9Ti, V-7.2Cr-14.5Ti, and V-17.7Ti alloys after neutron irradiation at 420 and 600 degrees C to 41--44 atom displacements per atom. The DBTTs determined for these vanadium alloys show that a vanadium alloy containing Cr and/or Ti and Si alloying additions to be used as a structural material in a fusion reactor should contain 3--11 wt % total alloying addition for maximum resistance to hydrogen- and/or irradiation-induced embrittlement. 4 refs., 3 figs., 2 tabs

  18. Study of dynamics and ground state structure of low and medium mass double hypernuclei

    M D Abdul Khan; Tapan Kumar Das

    2001-01-01

    We critically review the dynamics by examining - and -nucleon phenomenological potentials in the study of the bound state properties of double- hypernuclei $^{6}_{}$He, $^{10}_{}$Be, $^{14}_{}$C, $^{18}_{}$O, $^{22}_{}$Ne, $^{26}_{}$Mg, $^{30}_{}$Si, $^{34}_{}$S, $^{38}_{}$Ar, $^{42}_{}$Ca, $^{46}_{}$Ti, $^{50}_{}$Cr, $^{54}_{}$Fe, $^{58}_{}$Ni, $^{62}_{}$Zn, $^{66}_{}$Ge, $^{70}_{}$Se, $^{74}_{}$Kr, $^{78}_{}$Sr, $^{82}_{}$Zr, $^{86}_{}$Mo, $^{90}_{}$Ru, $^{94}_{}$Pd, $^{98}_{}$Cd, $^{102}_{}$Sn in the frame work of (core ++) three body model. An effective potential is obtained by folding the phenomenological potential into the density distribution of the core nuclei. The former two cases (i.e. $^{6}_{}$He and $^{10}_{}$Be) are revisited to justify the correctness of the present potential model. Assuming the same potential model we predicted some of the structural properties of heavier doubly -hypernuclei. The hyperspherical harmonics expansion method, which is an essentially exact method has been employed for the three body system. A convergence in binding energy up to 0.15% for max = 20 has been achieved. In our calculation we have made no approximation in restricting the allowed -values of the interacting pairs.

  19. Synthesis and structural and thermodynamical characterization of hollandite type material intended for the specific containment of cesium

    This thesis deals with the characterization of the Ba1Cs0.28Fe0.82Al1.46Ti5.72O16 hollandite envisaged for Cs containment. Techniques used are essentially classical powder XRD or synchrotron radiation at the absorption threshold of Ba and Cs, TEM and high-temperature calorimetry. Two syntheses have been studied: an alcoxide route and a dry route. After sintering, both routes lead to an incommensurate modulated tetragonal hollandite structure (space group: I4/m(00γ)00) with a modulation vector distribution. Before sintering, the material obtained by the alcoxide route is composed of three phases: a tetragonal hollandite like above, a monoclinic Ba-free hollandite and a weak-coherence-length phase containing only Ba. On contrary, the dry route already leads to the tetragonal hollandite at this step of the synthesis. High temperature oxide melt solution calorimetry was used to derive standard enthalpy of formation of hollandite to deduce its free enthalpy of formation. (author)

  20. Nuclear data for design analyses of the test blanket modules in ITER: Review and recommendations for EFF/JEFF evaluations

    This ppt-presentation gives an overview of ITER materials for nuclear analysis (Test Blanket Modules (TBM); Shield modules, vacuum vessel, plasma facing components; superconducting magnet, minor importance materials), a review of available nuclear data evaluations (EFF-3/JEFF-3.0 (EU); FENDL-2.0, JENDL-3.3, ENDF/B-VI; MF=6 data, co-variances, γ-production; benchmark analyses (data quality)) and recommendations for evaluations (priorities for EFF data evaluations in FP6; update/revision/completion of data evaluations according to needs for TBM design; extension for E > 20 MeV (IFMIF application)) for the isotopes 9Be, natPb, 204Pb, 206Pb, 208Pb, 6Li, 7Li, 28Si, 29Si, 30Si, 16O, 54Fe, 56Fe, 57Fe, 58Fe, 50Cr, 52Cr, 53Cr, 54Cr, natW, 182W, 183W, 184W, 186W, 181Ta, 63Cu, 65Cu, natTi, 46Ti, 47Ti, 48Ti, 49Ti, 12C, 23Na, 39K, 1H and many more

  1. fp shell spectroscopy: numerical calculations and theoretical aspects

    The fp shell spectroscopy is reviewed and the fsup(n) model is introduced. It is shown that the two-body Hamiltonian monopolar terms play a very important part in the behavior of these spectra, and that realistic interactions do not reproduce them. The detailed study of the following nuclei was undertaken: 47Ca, 48Ca, 49Ca, 56Ni, 48Sc, 50Sc, 50Ti, 46Ti, 50Cr, 47V and 49Cr. It is shown that very precise values of the few parameters defining the monopolar contributions could be extracted from the comparison between calculations and experimental data. The study of the binding energies of all the nuclei from 40Ca to 56Ni shows that it is necessary to introduce three-body forces. The results also reveal the effect of nondiagonal multipoles which are well reproduced by realistic interactions. A better understanding of the electromagnetic behavior of the fsup(n) nuclei of their conjugaison properties and of the relation between 42Sc and 48Sc was obtained. Several calculations of two-body transfer amplitudes were proposed

  2. Quantification of titanium from TiO2 particles in biological tissue.

    Faucher, Stéphane; Lespes, Gaëtane

    2015-10-01

    This study presents the development of a strategy for the quantification of titanium from titanium dioxide polydisperse particles (TiO2) in dry biological tissue. Calf liver was chosen as laboratory testing material. The challenge was to (i) obtain a complete mineralization of the solid material (biological tissue and TiO2) and (ii) ensure the accuracy of the determined concentrations with a sufficient sensitivity. Mineralization was performed using a mixture of concentrated nitric and hydrofluoric acids. Atomic mass spectrometry associated with light-scattering technique was used to control the physical state (dissolved and particle forms) of titanium and reliably estimate the total titanium concentration in calf liver. The monitoring of (46)Ti and (49)Ti, operating in helium collision/reaction cell mode, and using external calibration with internal standard addition, allowed the quantification of Ti while removing isobaric interferences. The limit of detection and quantification were 0.7 and 2.3μg (Ti)g(-1) (tissue) respectively. The mean analytical recovery over the whole procedure was (103±6)% in a range of concentrations from LOD to 200μg(Ti)g(-1) (tissue). PMID:26302910

  3. Design status of KOBRA for rare isotope production and direct measurements of radiative capture cross sections

    Tshoo, K.; Chae, H.; Park, J.; Moon, J. Y.; Kwon, Y. K.; Souliotis, G. A.; Hashimoto, T.; Akers, C.; Berg, G. P. A.; Choi, S.; Jeong, S. C.; Kato, S.; Kim, Y. K.; Kubono, S.; Lee, K. B.; Moon, C.-B.

    2016-06-01

    KOBRA (KOrea Broad acceptance Recoil spectrometer and Apparatus) facility being designed at Rare Isotope Science Project in Korea will be utilized to produce rare isotope beams by employing multi-nucleon transfer reactions at about 20 MeV/nucleon for studies of nuclear structure. KOBRA will also provide high suppression of beam induced background for direct measurements of radiative-capture cross sections in the astrophysical energy range. The present design status of the KOBRA facility is reported along with a brief introduction to the facility. We have studied the feasibility of production of 44Ti based on the present design of KOBRA as an example, and calculated the intensity of 44Ti secondary beam, to be about 105 particles per second, for 1 pnA 46Ti primary beam with a carbon target for a beam energy of 25 MeV/nucleon. A Monte Carlo simulation with a ray-tracing code has been performed to show that recoil products 66Se are well separated from a 65As beam by KOBRA for the 65As (p, γ)66Se reaction at a beam energy of 1 MeV/nucleon.

  4. Proton-capture studies of medium-weight nuclei

    This thesis describes the measurements on the reaction 46Ti(p,γ)47V in which some 40 bound states have been located, which have not been reported previously. Spins and/or parities and lifetimes have been determined for about the same number of bound states. It also describes experiments on the 62Ni(p,γ)63Cu reaction. The γ-ray decay of ten selected resonances in the proton-energy range Esub(p) = 1.1 - 1.7 MeV has been measured. Finally, experiments on the 36Ar(p,γ)37K reaction are reported. Due to the low Q-value (Q = 1.86 MeV) the lower levels of 37K correspond to well-isolated resonances. For the three nuclei studied, the experimental level schemes are compared with the results of shell-model calculations in which the strength parameters and single-particle energies have been fitted with the experimental level schemes. The results of the calculations agree quite well with the experimental data for 47V and 63Cu; for 37K they are still in progress. (Auth.)

  5. Quantification of copper and zinc species fractions in legume seeds extracts by SEC/ICP-MS: validation and uncertainty estimation.

    Mestek, Oto; Komínková, Jana; Koplík, Richard; Borková, Markéta; Suchánek, Miloslav

    2002-07-19

    Fractions of Cu and Zn species in legume samples (common white bean, pea, chick pea and lentil seeds and defatted soybean flour) were analysed by on-line hyphenation of size exclusion chromatography and inductively coupled plasma-mass spectrometry. Samples were extracted by 0.02 mol l(-1) Tris-HCl buffer solution, pH 7.5. The extraction efficiency lay in the region 60-90 and 60-80% for Cu and Zn, respectively. Quantification of elements in the individual chromatographic fractions was carried out by isotope dilution (ID) and external calibration (EC) techniques. For ID analysis the chromatographic effluent was mixed with the flow of (65)Cu and (68)Zn isotope enriched solution and the isotope ratio values (63)Cu/(65)Cu and ((64)Zn+(66)Zn)/(68)Zn were measured. In the case of EC technique calibration solutions of elements were injected to the flow of mobile phase by the second injector. Prior entering detector the effluent was mixed with the flow of internal standard solution (In, 50 mug l(-1)). Both methods have similar precision, however the behaviour of both studied elements was not the same. The chromatographic analysis itself was the main source of variability in the case of Cu. For Zn species analysis, the extraction process and the manipulation with the extract, played the significant role too. It was probably caused by lower stability of the present zinc chelates. The total amounts of Zn found in all chromatographic fractions represented 85-95% of Zn in sampled extract whereas those of Cu approached 100%. In case of small peaks the results of ID and EC were not the same. The EC results were lower then ID results. The great deal of results uncertainty accounts for the precision. PMID:18968719

  6. Fast neutron activation dosimetry with TLDS

    Pearson, D.W.; Moran, P.R.

    1975-01-01

    Fast neutron activation using threshold reactions is the only neutron dosimetry method which offers complete discrimination against gamma-rays and preserves some information about the neutron energy. Conventional activation foil technique requires sensitive radiation detectors to count the decay of the neutron induced activity. For extensive measurements at low neutron fluences, vast outlays of counting equipment are required. TL dosimeters are inexpensive, extremely sensitive radiation detectors. The work of Mayhugh et al. (Proc. Third Int. Conf. on Luminescence Dosimetry, Riso Report 249, 1040, (1971)) showed that CaSO/sub 4/: DyTLDs could be used to measure the integrated dose from the decay of the radioactivity produced in the dosimeters by exposure to thermal neutrons. This neatly combines the activation detector and counter functions in one solid state device. This work has been expanded to fast neutron exposures and other TL phosphors. The reactions /sup 19/F(n, 2n)/sup 18/F, /sup 32/S(n,p)/sup 32/P, /sup 24/Mg(n,p)/sup 24/, and /sup 64/Zn(n,p)/sup 64/Cu were found useful for fast neutron activation in commercial TLDs. As each TLD is its own integrating decay particle counter, many activation measurements can be made at the same time. The subsequent readings of the TL signals can be done serially after the induced radioactivity has decayed, using only one TL reader. The neutron detection sensitivity is limited mainly by the number statistics of the neutron activations. The precision of the neutron measurement is within a factor of two of conventional foil activation for comparable mass detectors. Commercially available TLDs can measure neutron fluences of 10/sup 9/n/cm/sup 2/ with 10 percent precision.

  7. Fast neutron activation dosimetry with TLDS

    Fast neutron activation using threshold reactions is the only neutron dosimetry method which offers complete discrimination against gamma-rays and preserves some information about the neutron energy. Conventional activation foil technique requires sensitive radiation detectors to count the decay of the neutron induced activity. For extensive measurements at low neutron fluences, vast outlays of counting equipment are required. TL dosimeters are inexpensive, extremely sensitive radiation detectors. The work of Mayhugh et al. (Proc. Third Int. Conf. on Luminescence Dosimetry, Riso Report 249, 1040, (1971)) showed that CaSO4: DyTLDs could be used to measure the integrated dose from the decay of the radioactivity produced in the dosimeters by exposure to thermal neutrons. This neatly combines the activation detector and counter functions in one solid state device. This work has been expanded to fast neutron exposures and other TL phosphors. The reactions 19F(n, 2n)18F, 32S(n,p)32P, 24Mg(n,p)24, and 64Zn(n,p)64Cu were found useful for fast neutron activation in commercial TLDs. As each TLD is its own integrating decay particle counter, many activation measurements can be made at the same time. The subsequent readings of the TL signals can be done serially after the induced radioactivity has decayed, using only one TL reader. The neutron detection sensitivity is limited mainly by the number statistics of the neutron activations. The precision of the neutron measurement is within a factor of two of conventional foil activation for comparable mass detectors. Commercially available TLDs can measure neutron fluences of 109n/cm2 with 10 percent precision

  8. Communication of nuclear data progress: No.14 (1995)

    Communication of Nuclear Data Progress (CNDP) in English is set up by Chinese Nuclear Data Center. This is the fourteenth issue, in which the achievements in nuclear data field for the last year in P.R. China are published. It includes the measurements of neutron activation cross sections for 64Zn(n,γ)65Zn, 23Na(n,2n)22Na, 92Mo(n,p)92mNb, 94Mo(n,2n)93mMo, 98Mo(n,p)98mNb, Ba(n,x)134Cs, 134Ba(n,2n)133Ba, 137Ba(n,p)137Cs, 140Ce(n,2n)139Ce, 142Ce(n,2n)141Ce, 179Hf(n,2n)178m2Hf and 209Bi(n,2n)208Bi reactions; calculation of neutron induced reactions on nuclides 175,176,NatLu and 89Y (emphatically on γ-production data); a γ-production data intercomparison system and intercomparison of Fe, Cr, Ni γ-production data; evaluations of n + 56Fe, 58,60,61,62,64,NatNi(n,α), 93Nb(n,2n), (n,n') and 58Ni, 87Rb, 89Y, 90Zr, 140Ce, 169Tm(n,2n) reaction cross sections; sensitivity of logft on ε branching to ground state of 197Au in decay of 197Hg; evaluated particle reflection data base, physical sputtering simulated calculation; progress on parameter and program libraries

  9. Study of collective movements: plane flow and azimuthal anisotropy

    One of the central problems of the heavy ion physics consists in the characterization of the nucleon-nucleon interaction in the nuclear matter. The study of collective flow appearing during the collisions allows by making use of the dynamical models (BUU, LVUU, QMD, etc.) to access to two basic interaction parameters: the nucleon-nucleon cross section in the nuclear environment, σnn and the nuclear matter incompressibility parameter, K∞. Our study focuses particularly on the matter flow in the reaction plane and on the competition between the emissions in and off the reaction plane for the light particles observed at mid-rapidity. Several experiments were carried out to achieve this aim: 36Ar on 27Al from 55 to 95 MeV/u and 64Zn on 58Ni from 36 to 79 MeV/u with the detector assembly MUR and TONNEAU, 36Ar on 58Ni from 32 to 95 MeV/u and Ni on Ni from 32 to 90 MeV/u with the INDRA multidetector. These detection systems allow obtaining a good classification according to the impact parameter as well as a good reconstitution of the reaction plane. The first results indicate for the the σnn a value of about 80% of the free nucleon -nucleon interaction cross section. Unfortunately, the limited range of the incident energy does not allow extracting so far a value for the K∞. This will be obtained only when the results from the Ni on Ni experiments at GANIL with INDRA and at SIS with FOPI will be combined. The INDRA experiments will provide also the parameter of flow and of anisotropy of H, He and Li

  10. Nucleosynthesis in the Hot Convective Bubble in Core-Collapse Supernovae

    Pruet, J; Woosley, S E; Buras, R; Janka, H; Hoffman, R D

    2004-09-02

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

  11. Absolute calibration of MC-ICP-MS isotopic composition measurements on natural-like zinc materials by means of synthetic isotopic mixtures

    In a technical report from 2002, the IUPAC (International Union for Pure and Applied Chemistry) highlights the lack of internationally accepted Isotopic Certified Reference Materials (ICRMs) for 5 chemical elements, including zinc. Also, the isotopic composition of natural zinc has not yet been calibrated in an absolute way. IRMM (Institute for Reference Materials and Measurements) launched the production of zinc ICRMs to calibrate mass spectrometric measurements and allow traceability of results for this element to the Systeme International d'Unite (SI). Isotopic data based on measurements calibrated by means of these ICRMs and issued from different laboratories become immediately comparable. The most common way of calibrating the values (i.e. correction for mass discrimination effects during their measurements) carried by these ICRMs consists of two steps. Several synthetic isotopic mixtures covering a wide enough range of isotope ratios (4-5 orders of magnitude) are produced from the gravimetric mixing of purified isotopically enriched materials. The results obtained for the measurements by mass spectrometry on all these mixtures and enriched materials, combined with gravimetric data, permit the quantification (iterative calculations) of the mass discrimination effects. Ten different synthetic isotopic mixtures of Zn were produced by mixing 64Zn, 67Zn and 68Zn enriched materials, and all these mixtures and enriched materials were measured by Multi-Collector Inductively Couple Plasma Mass Spectrometry (MC-ICP-MS). This presentation will introduce the analytical procedure and will present calibrated results obtained for a set of various natural-like Zn materials. The validation aspect of the work will particularly emphasise: - the propagation together of all identified sources of uncertainty following the ISO/GUM guidelines; - the excellent consistency observed between these results and the data obtained on identical samples using a different MC-ICP-MS as well as

  12. Mass and beta decay of the N = Z isotope {sup 68}Se

    Blumenthal, D.J.; Davids, C.N.; Lister, C.J. [and others

    1995-08-01

    An experiment to measure the mass and beta decay of the N = Z nuclide {sup 68}Se was performed. The properties of {sup 68}Se are important for determining the abundance of proton-rich nuclei such as {sup 60}Ni and {sup 64}Zn, which are thought to be formed in the alpha-rich freezeout stage of a giant star. The abundances of the even-even N = Z nuclei such as {sup 60}Zn, {sup 64}Ge, and {sup 68}Se depend on the competition between ({alpha},{gamma}) and ({gamma},{alpha}) reactions, whose rates depend sensitively on the reaction Q-values. In addition, the half-life of {sup 68}Se is important in determining the path of the explosive rp-process, since reactions such as (p,{gamma}) must compete with beta decay in order to push the rp path to heavier nuclei. Using the moving tape collector system and the {sup 12}C({sup 58}Ni,2n){sup 68}Se reaction at 200 MeV, recoils were mass-selected by a slit at the FMA focal plane and implanted into the tape. After a 50-second collection period, the accumulated activity was moved to the counting position between two Ge gamma-ray detectors or a plastic scintillator beta detector and a Ge detector. The half-life of {sup 68}Se was determined to be 37 {plus_minus} 5 s, in agreement with other measurements. Gamma-gamma and beta-gamma coincidence data are under analysis, to produce the decay scheme and the electron capture decay energy.

  13. Compilation and evaluation of 14-MeV neutron-activation cross sections for nuclear technology applications. Set I

    Available 14-MeV experimental neutron activation cross sections are compiled and evaluated for the following reactions of interest for nuclear-energy technology applications: 27Al(n,p)27Mg, Si(n,X)28Al, Ti(n,X)46Sc, Ti(n,X)47Sc, Ti(n,X)48Sc, 51V(n,p)51Ti, 51V(n,α)48Sc, Cr(n,X)52V, 55Mn(n,α)52V, 55Mn(n,2n)54Mn, Fe(n,X)54Mn, 54Fe(n,α)51Cr, 59Co(n,p)59Fe, 59Co(n,α)56Mn, 59Co(n,2n)58Co, 65Cu(n,p)65Ni, Zn(n,X)64Cu, 64Zn(n,2n)63Zn, 113In(n,n')/sup 113m/In, 115In(n,n') /sup 115m/In. The compiled values are listed and plotted for reference without adjustments. From these collected results those values for which adequate supplementary information on nuclear constants, standards and experimental errors is provided are selected for use in reaction-by-reaction evaluations. These data are adjusted as needed to account for recent revisions in the nuclear constants and cross section standards. The adjusted results are subsequently transformed to equivalent cross sections at 14.7 MeV for the evaluation process. The evaluations are performed utilizing a least-squares method which considers correlations between the experimental data. 440 refs., 41 figs., 46 tabs

  14. Zinc isotope and transition-element dynamics accompanying hydrozincite biomineralization in the Rio Naracauli, Sardinia, Italy

    Wanty, Richard B.; Podda, F.; De Giudici, Giovanni; Cidu, R.; Lattanzi, Pierfranco

    2013-01-01

    The Rio Naracauli in SW Sardinia drains part of the Ingurtosu Zn–Pb mining district, and contains extreme concentrations of dissolved Zn at near-neutral pH. In the upper reaches of the stream, pH, alkalinity and Zn concentrations are such that hydrozincite [Zn5(CO3)2(OH)6] precipitates in a biologically mediated process facilitated by a microalga (Chlorella sp.) and a cyanobacterium (Scytonema sp.). Values of δ66Zn in water and solid samples ranged from − 0.35‰ to + 0.5‰ relative to the JMC 3-0749-Lyon standard, and closely follow a mass-dependent fractionation line. Two composite samples of sphalerite, the primary ore mineral in the Ingurtosu deposits, had an average δ66Zn of + 0.15‰, similar to sphalerite measured elsewhere in hydrothermal mineral deposits. Zinc isotope measurements of the stream water and the hydrozincite forming in the stream show a consistent preference for the heavy isotope, 66Zn, in the hydrozincite relative to 64Zn. Synthetic hydrozincites produced without added bacteria have δ66Zn identical to the dissolved Zn, thus suggesting a biologically mediated mineralization process in Rio Naracauli. The average fractionation, Δhdz-water, is 0.35‰, the magnitude of which is consistent with other studies, and suggests an extracellular mechanism of the biomineralization process. Zinc concentration and dissolved δ66Zn steadily decrease in the reach of the stream where the biomineralization occurs. The biomineralization process also leads to the sequestration of Pb, Cu and Ni in the hydrozincite lattice, and the coeval precipitation of an amorphous CdCO3 solid, prompting the suggestion that if optimized, the biomineralization process might represent a feasible passive remediation strategy for streams with high Zn and other metals, and with near-neutral pH.

  15. Composition of the Innermost Core Collapse Supernova Ejecta and the νp-Process

    Fröhlich, C.; Liebendörfer, M.; Martínez-Pinedo, G.; Thielemann, F.-K.; Bravo, E.; Zinner, N. T.; Hix, W. R.; Langanke, K.; Mezzacappa, A.; Nomoto, K.

    2006-07-01

    With presently known input physics and computer simulations in 1D, a self-consistent treatment of core collapse supernovae does not lead to explosions, while 2D models show some promise. Thus, there are strong indications that the delayed neutrino mechanism works combined with a multi-D convection treatment for unstable layers. On the other hand there is a need to provide correct nucleosynthesis abundances for the progressing field of galactic evolution and observations of low metallicity stars. The innermost ejecta is directly affected by the explosion mechanism, i.e. most strongly the yields of Fe-group nuclei for which an induced piston or thermal bomb treatment will not provide the correct yields because the effect of neutrino interactions is not included. We apply parameterized variations to the neutrino scattering cross sections and alternatively, parameterized variations to the neutrino absorption cross sections on nucleons in the ``gain region''. We find that both measures lead to similar results, causing explosions and a Ye larger than 0.5 in the innermost ejected layers, due to the combined effect of a short weak interaction time scale and a negligible electron degeneracy, unveiling the proton-neutron mass difference. The proton-rich environment results in enhanced abundances of 45Sc, 49Ti, and 64Zn as requested by chemical evolution studies and observations of low metallicity stars. Moreover, antineutrino capture on the free protons allows for an appreciable production of nuclei in the mass range up to A = 80 by the νp-process.

  16. The ground state infrared spectra of several isotopic forms of the CdH and ZnH radicals

    The infrared spectra of six isotopic forms of cadmium monohydride, [116CdH (7.6%), 114CdH (28.9%), 113CdH (12.3%), 112CdH (24.1%), 111CdH (12.7%), and 110CdH (12.4%)] and four isotopic forms of zinc hydride [68ZnH (18.6%), 67ZnH (4.1%), 66ZnH (27.8%), and 64ZnH (48.9%)] have been observed in natural abundance in their ground electronic state (2Σ+) in the gas phase using a diode laser spectrometer. A number of transitions of 108CdH (0.9%) and 106CdH (1.2%) and 70ZnH (0.6%) were also observed, but too little data was accumulated to allow a good analysis. The hydrides were produced by reaction of hydrogen with metal vapor at elevated temperature in an electric discharge. The analysis of the experimental data was carried out in two ways. (a) A complete set of Dunham parameters and spin--rotation parameters (γ parameters) was determined for each isotopic species of the two radicals and (b) a set of mass-independent parameters were calculated for both ZnH and CdH. Since only information over the isotopic species of the heavy atom was produced in each case, effects arising from a breakdown of the Born--Oppenheimer approximation were negligible. The effects of the strong anharmonicity present in these two molecules on the values of the parameters are discussed

  17. Imaging of copper, zinc, and other elements in thin section of human brain samples (hippocampus) by laser ablation inductively coupled plasma mass spectrometry.

    Becker, J S; Zoriy, M V; Pickhardt, C; Palomero-Gallagher, N; Zilles, K

    2005-05-15

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) was used to produce images of element distribution in 20-microm thin sections of human brain tissue. The sample surface was scanned (raster area approximately 80 mm(2)) with a focused laser beam (wavelength 213 nm, diameter of laser crater 50 microm, and laser power density 3 x 10(9) W cm(-2)) in a cooled laser ablation chamber developed for these measurements. The laser ablation system was coupled to a double-focusing sector field ICPMS. Ion intensities of 31P+, 32S+, 56Fe+, 63Cu+, 64Zn+, 232Th+, and 238U+ were measured within the area of interest of the human brain tissue (hippocampus) by LA-ICPMS. The quantitative determination of copper, zinc, uranium, and thorium distribution in thin slices of the human hippocampus was performed using matrix-matched laboratory standards. In addition, a new arrangement in solution-based calibration using a micronebulizer, which was inserted directly into the laser ablation chamber, was applied for validation of synthetic laboratory standard. The mass spectrometric analysis yielded an inhomogeneous distribution (layered structure) for P, S, Cu, and Zn in thin brain sections of the hippocampus. In contrast, Th and U are more homogeneously distributed at a low-concentration level with detection limits in the low-nanogram per gram range. The unique analytical capability and the limits of LA-ICPMS will be demonstrated for the imaging of element distribution in thin cross sections of brain tissue from the hippocampus. LA-ICPMS provides new information on the spatial element distribution of the layered structure in thin sections of brain tissues from the hippocampus. PMID:15889910

  18. Fractionation of Cu and Zn isotopes during adsorption onto amorphous Fe(III) oxyhydroxide: Experimental mixing of acid rock drainage and ambient river water

    Balistrieri, L.S.; Borrok, D.M.; Wanty, R.B.; Ridley, W.I.

    2008-01-01

    Fractionation of Cu and Zn isotopes during adsorption onto amorphous ferric oxyhydroxide is examined in experimental mixtures of metal-rich acid rock drainage and relatively pure river water and during batch adsorption experiments using synthetic ferrihydrite. A diverse set of Cu- and Zn-bearing solutions was examined, including natural waters, complex synthetic acid rock drainage, and simple NaNO3 electrolyte. Metal adsorption data are combined with isotopic measurements of dissolved Cu (65Cu/63Cu) and Zn (66Zn/64Zn) in each of the experiments. Fractionation of Cu and Zn isotopes occurs during adsorption of the metal onto amorphous ferric oxyhydroxide. The adsorption data are modeled successfully using the diffuse double layer model in PHREEQC. The isotopic data are best described by a closed system, equilibrium exchange model. The fractionation factors (??soln-solid) are 0.99927 ?? 0.00008 for Cu and 0.99948 ?? 0.00004 for Zn or, alternately, the separation factors (??soln-solid) are -0.73 ?? 0.08??? for Cu and -0.52 ?? 0.04??? for Zn. These factors indicate that the heavier isotope preferentially adsorbs onto the oxyhydroxide surface, which is consistent with shorter metal-oxygen bonds and lower coordination number for the metal at the surface relative to the aqueous ion. Fractionation of Cu isotopes also is greater than that for Zn isotopes. Limited isotopic data for adsorption of Cu, Fe(II), and Zn onto amorphous ferric oxyhydroxide suggest that isotopic fractionation is related to the intrinsic equilibrium constants that define aqueous metal interactions with oxyhydroxide surface sites. Greater isotopic fractionation occurs with stronger metal binding by the oxyhydroxide with Cu > Zn > Fe(II).

  19. Compilation and evaluation of 14-MeV neutron-activation cross sections for nuclear technology applications. Set I

    Evain, B.P.; Smith, D.L.; Lucchese, P.

    1985-04-01

    Available 14-MeV experimental neutron activation cross sections are compiled and evaluated for the following reactions of interest for nuclear-energy technology applications: /sup 27/Al(n,p)/sup 27/Mg, Si(n,X)/sup 28/Al, Ti(n,X)/sup 46/Sc, Ti(n,X)/sup 47/Sc, Ti(n,X)/sup 48/Sc, /sup 51/V(n,p)/sup 51/Ti, /sup 51/V(n,..cap alpha..)/sup 48/Sc, Cr(n,X)/sup 52/V, /sup 55/Mn(n,..cap alpha..)/sup 52/V, /sup 55/Mn(n,2n)/sup 54/Mn, Fe(n,X)/sup 54/Mn, /sup 54/Fe(n,..cap alpha..)/sup 51/Cr, /sup 59/Co(n,p)/sup 59/Fe, /sup 59/Co(n,..cap alpha..)/sup 56/Mn, /sup 59/Co(n,2n)/sup 58/Co, /sup 65/Cu(n,p)/sup 65/Ni, Zn(n,X)/sup 64/Cu, /sup 64/Zn(n,2n)/sup 63/Zn, /sup 113/In(n,n')/sup 113m/In, /sup 115/In(n,n') /sup 115m/In. The compiled values are listed and plotted for reference without adjustments. From these collected results those values for which adequate supplementary information on nuclear constants, standards and experimental errors is provided are selected for use in reaction-by-reaction evaluations. These data are adjusted as needed to account for recent revisions in the nuclear constants and cross section standards. The adjusted results are subsequently transformed to equivalent cross sections at 14.7 MeV for the evaluation process. The evaluations are performed utilizing a least-squares method which considers correlations between the experimental data. 440 refs., 41 figs., 46 tabs.

  20. Simultaneous imaging and treatment of vulnerable plaques with tin-117m-DOTA-Annexin

    Full text of publication follows. Tin-117m is a useful radionuclide both for radionuclide imaging (gamma emission 159 keV, 86%), and for radionuclide therapy (conversion electrons 141 keV, 114%). Sn-117m labeled Annexin-V demonstrates promise for the noninvasive molecular imaging and treatment of active atheromatous disease [vulnerable plaque (VP), also known as thin-cap fibroatheroma (TCFA)] [Ref.1]. The rupture of VP's is a major cause of myocardial infarction and stroke. A majority of all significant cardiac events (∼ 70%) leading to MI, including sudden death, are caused by the rupture of these thin-cap fibroatheroma lesions. VP is usually covered by a thin cap on the lumen side, and when ruptured, highly thrombogenic material is released that activates clotting cascade and induces thrombosis. We have developed and used (i) Sn-117m electroplated coronary stents (Sn-117m stents), and (ii) Sn-117m-DOTA-Annexin [TA] for evaluating the possibility of simultaneous imaging and therapy of VP with this dual-purpose (theragnostic) radionuclide. At therapeutic doses, the conversion electrons from Sn-117m have been shown to reduce inflammation, and thus, are ideal for treating VP's, as their range in tissue (∼300 μm) is approximately the same as the VP thickness in human coronary arteries. In hyperlipidaemic rabbit aortas, TA was shown to bind to macrophage cells undergoing apoptosis, which are present in abundance in VP's. In relatively low doses, TA was able to image the plaque using traditional SPECT/CT cameras. Studies in a similar rabbit model, sacrificed 3 days after Sn-117m-stent implantation [4 doses: 0 (cold tin), 30, 60, and 150 μCi Sn-117m per 15-mm stent), upon histochemical analysis of proliferating macrophages and smooth muscle cells, demonstrated that inflammatory cells in the Sn-117m-stented segments were dramatically reduced in a dose-dependent manner. In recent studies in an Apo-E mouse VP model, TA has demonstrated a significant

  1. The episodic influx of tin-rich cosmic dust particles during the last ice age

    LaViolette, Paul A.

    2015-12-01

    This paper presents evidence of the first detection of interstellar dust in ice age polar ice. Neutron activation analysis (NAA) results are reported for 15 elements found in dust filtered from eight samples of Camp Century Greenland ice dating from 40 to 78 kyrs BP. High concentrations of Sn, Sb, Au, Ag, Ir, and Ni were found to be present in three out of these eight samples. One compositionally anomalous dust sample from an ice core depth of 1230.5 m (age ∼49 kyrs BP, near the beginning of D/O stadial No. 13) was found to contain tin with an average weight percent of 49% as determined by energy dispersive X-ray analysis (EDS). This sample was also found to contain high concentrations of Pb with an average weight abundance of 8.4% and matching the Sn:Pb ratio observed in interstellar spectra. Dust particles in this sample generally have a platy morphology and range from submicron size up to a size as large as 120 μm, a particle consisting almost entirely of SnO2 and being the largest monomineralic extraterrestrial dust particle so far discovered. One porous aggregate tin-bearing particle was found to contain nanometer sized chondrules indicating an extraterrestrial origin. The extraterrestrial origin for the tin is also indicated by the presence of isotopic anomalies in the 114Sn, 115Sn and 117Sn isotopes. Follow up isotopic measurements of this tin-rich dust need to be performed to improve confidence in the anomalies reported here. High abundances of the low melting point elements Ag, Au, and Sb are also present in this tin-rich sample along with elevated abundances of the siderophiles Ir, Ni, Fe, and Co, the latter being present in chondritic proportions and indicating that about 9% of the dust has a C1 chondrite component. Measurements indicate that about 97% of this dust is of extraterrestrial origin with a 3% residual being composed of terrestrial windblown dust. EDS analysis of another tin-rich Camp Century ice core dust sample dating to ∼130 kyrs BP

  2. Synthesis, characterization and thermochemistry of Cs-, Rb- and Sr-substituted barium aluminium titanate hollandites

    Highlights: • Cs-, Rb- and Sr-substituted barium titanate hollandites were synthesized using sol–gel methods. • Chemical compositions were determined by electron microprobe analyses. • Crystal structures were analyzed using powder synchrotron X-ray diffraction coupled with Rietveld refinements. • Enthalpies of formation were measured using high temperature oxide melt solution calorimetry. • Stability relations with respect to BaTiO3 and SrTiO3 perovskites and other oxides were determined. - Abstract: Titanate hollandites are of considerable interest for immobilization of radioactive Cs, its daughter product Ba and related radionuclides Rb and Sr. In this study, we synthesized three hollandites, Ba1.18Cs0.21Al2.44Ti5.53O16, Ba1.17Rb0.19Al2.46Ti5.53O16 and Ba1.14Sr0.10Al2.38Ti5.59O16, using sol–gel methods. Rietveld analysis of synchrotron XRD data shows that they adopt the tetragonal structure (space group I4/m), and their cell parameters increase with increasing cation size (Sr2+ → Rb+ → Cs+). Standard enthalpies of formation of these hollandites were determined from drop solution calorimetric measurements with lead borate as the solvent at 973 K. Their formation enthalpies are similar, consistent with the occurrence of extensive cation substitutions in hollandites. Further energetic analysis with respect to BaTiO3 and SrTiO3 perovskites and other oxides reveals decreased thermodynamic stability from Cs- to Rb- to Sr-hollandite. This trend is consistent with the phase assemblage observed in Synroc, where Cs+, Rb+ and Ba2+ enter into hollandite, whereas Sr2+ occurs in perovskite

  3. Lifetime measurements in 47Ti and 49Cr

    The Doppler shift attenuation method has been used to measure lifetime limits. Precise excitation energies, branching ratios, and decay scheme information were also extracted from the experimental data and compared with model calculations in order to investigate the structure of low-lying states in 47Ti and 49Cr. States were populated with the 47Ti(p,p'γ)47Ti, 44Ca(α,nγ)47Ti, and 46Ti(α,nγ)49Cr reactions. Approximately forty-four states of 47Ti above 2.2 MeV excitation and three states of 49Cr above 2.5 MeV excitation were studied. The present results allow spin and parity assignments. States in 47Ti form a K/sup π/ = 3/2+ rotational band. Transition rates and other information obtained in the experimental phase of this work are compared with predictions of the rotation-particle coupling (RPC) model, the deformed configuration mixing (DCM) shell model, and the spherical shell model with (f/sub 7/2/)/sup n/ configurations. The DCM model gives an excellent account of the properties of low-lying states of 47Ti and a reasonable account of low-lying states of 49Cr; the simpler RPC model does a fair job in describing yrast levels of both nuclei; the (f/sub 7/2/)/sup n/ model is least successful. An apparent fall-off in E2 enhancement for transitions from higher yrast levels may indicate a decrease in collective behavior at higher angular momenta, however. In the course of studying the RPC model, a confusion over the proper treatment of hole excitations was investigated and eliminated, and the implications of requiring model states to have good isospin were explored

  4. Evaluation of neutron flux in the WWR-SM reactor channel and in the irradiating zone of U-150 cyclotron

    Full text: For effective work of a reactor, and correct planning of experiments related to the reactor irradiation of various materials it is required to control a neutron flux in the given irradiation point for a long irradiation period. For realization of research works on topazes ennobling under irradiation by reactor neutrons as well as by secondary neutrons produced in a cyclotron it is necessary to know the total neutron flux and spectra. To resolve the problem a technique for registration of neutrons with different energy and calculation of a neutrons spectrum in the given irradiation points in reactor channels and in cyclotron behind the nickel target has been developed. Neutron flux density and energy spectra were monitored by use of the following nuclear reactions: 59Co(n,γ)60Co, 197Au(n,γ)198Au, 58Ni(n,p)58Co, 24Mg(n,p)24Na, 48Ti(n,p)48Sc, 46Ti(n,p)46Sc, 54Fe(n,p)54Mn, 89Y(n,2n)88Y, 60Ni(np)60Co. Gamma spectrometer composed of HPGe detector (Rel. Eff. - 15%) and Digital Spectra Analyzer DSA-1000 (Canberra Ind., USA) was used to measure gamma activity of irradiated samples. Acquired gamma spectra were processed by means of Genie 2000 standard software package. The σ(E) functions and neutron spectra were calculated by using the least squares method and approximating the tabular and experimental data with power polynomials. The developed technique was applied for the adjustment of the topazes irradiation regimes in the reactor core and under secondary neutrons flux from a nickel target in the cyclotron. The given technique allows to calculate a logarithmic spectrum of neutrons in a energy range from 0,025 eV up to 12 MeV with the uncertainty of about 10 %. (author)

  5. Thermochemical investigations of zirconolite, pyrochlore and brannerite: Three materials relevant to issues of plutonium immobilization

    Helean, Katheryn Bridget

    For the purpose of immobilizing plutonium, a crystalline ceramic waste form is being developed that can be described as a pseudo-quaternary system consisting of CaHfTi2O7- CaPuTi2O7- CaUTi2O7- GdTi2O7. High-temperature oxide melt solution calorimetry offers an effective methodology for the determination of enthalpies of formation of rare earth-bearing and other refractory oxides relevant to the proposed waste form. Calorimetric investigations of the waste form end-member phases (using Ce as a Pu analogue) plus brannerite, the major waste form impurity, were conducted using 3Na2O•4MoO3 solvent at 975 K. Standard enthalpies of formation, DeltaH°f (kJ/mol), were derived for three pyrochlore phases: Ca0.93Ce1.00Ti 2.035O7.00 (-3656.0 +/- 5.6), Ca1.46U 4+0.23U6+0.46Ti1.85O 7.00 (-3610.6 +/- 4.1) and Gd2Ti2O 7 (-3822.5 +/- 4.9). Enthalpies of formation with respect to an oxide phase assemblage, DeltaH°f-ox: CaO+MO2+2TiO2=CaMTi2O7 or Gd 2O3+2TiO2=Gd2Ti2O7 , and an oxide/perovskite phase assemblage, DeltaH° f-pv+ox: CaTiO3+MO2+TiO2=CaMTi 2O7, M = Ce, U were also calculated. DeltaH° f-ox (kJ/mol): Gd2Ti2O7 (-113.4 +/- 2.8); Ca1.46U4+0.23U 6+0.46Ti1.85O7.00 (-123.1 +/- 3.4); Ca0.93Ce1.00Ti2.035O7.00 (-54.1 +/- 5.2). DeltaH°f-pv+ox (kJ/mol): Ca1.46U4+0.23U6+ 0.46Ti1.85O7.00 (-5.1 +/- 4.0); Ca 0.93Ce1.00Ti2.035O7.00 (+21.0 +/- 5.5). A significant metastability field was defined with respect to an oxide/perovskite phase assemblage. DeltaH°f (kJ/mol) were derived for two zirconolite phases: CaZr1.03Ti1.97O7 (-3719.4 +/- 3.9) and CaHf1.02Ti1.98O 7 (-3720.5 +/- 3.9). DeltaH° f-ox (kJ/mol): CaZr1.03Ti1.97O7 (-89.6 +/- 2.8); CaHf1.02Ti1.98O7 (-74.8 +/- 3.1). CaZr1.03Ti1.97O7 was stable with respect to a perovskite plus oxides assemblage (DeltaH° f-pv+ox = -8.8 +/- 3.3 kJ/mol). CaHf1.02Ti 1.98O7 was marginally metastable in enthalpy (Delta H°f-pv+ox = +6.0 +/- 3.5 kJ/mol). DeltaH°f (kJ/mol) were derived for three brannerites: CeTi2O6 (-2948.8 +/- 4.3); U0.97Ti2.03O6

  6. Fast neutron radiography using photoluminescent imaging plates

    Fast neutron radiography (FNR) and resonance neutron radiography (RNR) are complementary to the conventional radiography with high energy gamma-rays or brems-strahlung radiation used for the inspection of thick metal objects. In both non-destructive methods, the contrast sensitivity and the penetration power can be improved by using higher energy neutrons. At present direct techniques based either n Solid State Nuclear Track detectors (SSNTDs) or scintillating screens and transfer techniques using activation threshold detectors and radiographic films are applied for the detection of fast neutron images. Rather low detection sensitivity of film and SSNTD based fast neutron imaging methods and also rather poor inherent image contrast of SSNTD pose a problem for FNR in the fast neutron energy region 1-15 MeV interesting for NDT. For more efficient detection of fast neutron images the use of novel highly sensitive photoluminescent imaging plates (IP) in combination with threshold at the KFKI research reactor. The conventional IP produced by FUJI Photo Film Co. for the detection of beta and X-ray radiation were used. The threshold activation detectors were the reactions 115In(n, n') 115mIn, 64Zn(n,p) 64Cu, 56Fe(n, p)56Mn, 24Mg(n, p)24Na and 27Al(n, α)24Na. These threshold reactions cover the fast neutron energy region between 0,7 MeV and 12 MeV. Pure, commercially available metals 0,1 mm to 0,25 mm thick made of In, Zn, Fe, Mg and Al were used as converter screens. The very high sensitivity of IP, the linearity of their response over 5 decades of exposure dose and the high dynamic digitalisation latitude enabled fast neutron radiography of image quality comparable to the quality of thermal NR. In our experimental conditions (φn∼ 108 n/cm2s, RCd ∼ 2) the neutron exposure and IP exposure periods were still practical and comparable to the half life of the corresponding reaction products (half an hour to several hours). Even with the 27Al(n.α)24Na reaction having a

  7. Separation of Radiocopper 64/67Cu from the Matrix of Neutron-Irradiated Natural Zinc Applicable for 64Cu Production

    S. Soenarjo

    2012-04-01

    Full Text Available Radioisotope 64Cu is a promising radiometallic-isotope for molecular-targeted-radiopharmaceuticals. Having a half-life of 12.70 hours and emitting β+-radiation (E+ = 0.6531 MeV as well as β—ray (E = 0.5787 MeV, it is widely used in the form of biomedical-substrate-radiopharmaceutical for positron emission tomography (PET diagnosis and simultaneously for targeted radiotherapy of cancer. The potential needs on the availability of 64Cu-labeled pharmaceuticals for domestic nuclear medicine hospitals lead to a necessity for the local production of carrier-free 64Cu using BATAN’s G.A. Siwabessy reactor because of the technical and economical constraints in the production using BATAN’s cyclotron. The presented work is accordingly to study whether the radioisotope 64Cu can be produced and separated from the matrix of post-neutron-irradiated-natural zinc. This study is expected can be further improved and implemented in production technology of carrier-free 64Cu based on 64Zn (n,p 64Cu nuclear reaction exploiting the fast neutron fraction among the major thermal fraction due to unavailability of fast-neutron-irradiation facility in the BATAN’s G.A. Siwabessy reactor. The solution of post-neutron-irradiated-natural zinc in 1M acetic acid was loaded into Chelex-100 cation exchanger resin column to pass out the Zn/Zn* fraction whereas the Cu* fraction which remained in the column was then eluted out from the column by using 1.5 M HCl and loaded into the second column containing Dowex-1X8 anion exchanger resin. The second column was then eluted with 0.5 M HCl. The collected eluate was expected to be zinc-free Cu* fraction. It was observed from the half-life and the -spectrometric analysis that radioactive copper-64Cu containing 67Cu was produced by neutron activation on the natural Zn-foil target and can be separated from the target matrix by the presented two-steps-column-chromatographic separation technique. The radioactivity

  8. Separation of Radiocopper 64/67Cu from the Matrix of Neutron-Irradiated Natural Zinc Applicable for 64Cu Production

    Radioisotope 64Cu is a promising radiometallic-isotope for molecular-targeted-radiopharmaceuticals. Having a half-life of 12.70 hours and emitting β+-radiation (Eβ+ = 0.6531 MeV) as well as β-ray (Eβ- = 0.5787 MeV), it is widely used in the form of biomedical-substrate-radiopharmaceutical for positron emission tomography (PET) diagnosis and simultaneously for targeted radiotherapy of cancer. The potential needs on the availability of 64Cu-labeled pharmaceuticals for domestic nuclear medicine hospitals lead to a necessity for the local production of carrier-free 64Cu using BATAN's G.A. Siwabessy reactor because of the technical and economical constraints in the production using BATAN's cyclotron. The presented work is accordingly to study whether the radioisotope 64Cu can be produced and separated from the matrix of post-neutron-irradiated-natural zinc. This study is expected can be further improved and implemented in production technology of carrier-free 64Cu based on 64Zn (n,p) 64Cu nuclear reaction exploiting the fast neutron fraction among the major thermal fraction due to unavailability of fast-neutron-irradiation facility in the BATAN's G.A. Siwabessy reactor. The solution of post-neutron-irradiated-natural zinc in 1M acetic acid was loaded into Chelex-100 cation exchanger resin column to pass out the Zn/Zn* fraction whereas the Cu* fraction which remained in the column was then eluted out from the column by using 1.5 M HCl and loaded into the second column containing Dowex-1X8 anion exchanger resin. The second column was then eluted with 0.5 M HCl. The collected eluate was expected to be zinc-free Cu* fraction. It was observed from the half-life and the γ-spectrometric analysis that radioactive copper-64Cu containing 67Cu was produced by neutron activation on the natural Zn-foil target and can be separated from the target matrix by the presented two-steps-column-chromatographic separation technique. The radioactivity measurement showed that wrapping the

  9. Nano confinement induced isotope separation of zinc: density functional theoretical modelling

    Crown ether has shown potential for isotope separation. Zinc has five stable isotopes of masses 64, 66, 67, 68 and 70 with natural abundances 48.63, 27.90, 4.10, 18.75 and 0.62%, respectively. 64Zn-depleted zinc is used in the primary coolant of nuclear power plant to reduce the formation of radioactive cobalt isotope, 60Co, presence of which leads to radiation threat to the working personal. It will be worthwhile to investigate whether crown ether can also be used for isotope separation of Zinc. DFT based electronic structure calculation using Turbomole package was performed to evaluate the isotope separation factor of Zn with crown ether of different nano confinement. In order to compute the isotope separation factor for any biphasic system we need to know the value of reduced partition function ratio (RPFR) for a pair of isotope in the feed solvent phase and the product complex phase. Hence, first the RPFR of hydrated Zn2+-(H2O)n (n=1-6) cluster system was calculated for different pair of Zn isotope. The computed value of RPFR was found to be increased from n=1 then shows maximum at n=4 and then further reduced. The working value of RPFR at n=4 were taken as 1.0098 for Zn (68/64); 1.005 for Zn (66/64) and 1.0047 for Zn (68/66). The highest separation factor is limited by the value of RPFR in water system. Next, the values of RPFR of complexes of Zn2+ ion with different crown ethers were computed. It is interesting to mention that the RPFR was found to be decreased from B12C4 to DB18C6 for all the pair of Zn isotopes studied here. The RPFR was found to be highest with B12C4 and lowest with DB18C6 leading to lowest separation factor in B12C4 and highest separation factor in DB18C6. Further, the separation factor was found to be highest for Zn (68/64) pair and lowest for Zn (68/66) pair as expected because in the former pair the mass difference is highest. It is worth noting that the RPFR can be correlated with the binding energy and free energy of complexation

  10. Excess Heat Production in Pd/D during Periodic Pulse Discharge Current in Various Conditions

    Karabut, A. B.

    2006-02-01

    Experimental data from low-energy nuclear reactions (LERN) in condensed media are presented. The nuclear reactions products were found in solid cathode media used in glow discharge. Apparently, the nuclear reactions were initiated when bombarding the cathode surface by plasma ions with the energy of 1.0-2.0 keV. Excess heat from a high current glow discharge reaction in D2, Xe, and Kr using cathodes already charged with preliminary deuterium-charged Pd and Ti cathode samples are given. Excess heat up to 10-15 W and efficiency up to 130% was recorded under the experiments for Pd cathode samples in D2 discharge. Excess heat up to 5 W and efficiency up to 150% was recorded for Pd cathodes that were charged with deuterium before the run, in Xe and Kr discharges. At the same time excess heat was not observed for pure Pd cathode samples in Xe and Kr discharges. The formation of impurity nuclides (7Li, 13C, 15N, 20Ne, 29Si, 44Ca, 48Ca, 56Fe, 57Fe, 59Co, 64Zn, 66Zn, 75As, 107Ag, 109Ag, 110Cg, 111Cg, 112Cg, 114Cg, and 115In) with the efficiency up to 1013 at./s was recorded. The isotopic ratios of these new nuclides ware quite different from the natural ratios. Soft X-ray radiation from the solid-state cathode with the intensity up to 0.01 Gy/s was recorded in experiments with discharges in H2, D2, Ar, Xe, and Kr. The X-ray radiation was observed in bursts of up to 106 photons, with up to 105 bursts per second while the discharge was formed and within 100 ms after turning off the discharge current. The results of the X-ray radiation registration showed that the exited energy levels have a lifetime up to 100 ms or more, and the energy of 1.2-2.5 keV. A possible mechanism for producing excess heat and nuclear transmutation reactions in the solid medium with the exited energy levels is considered.