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Sample records for 46ti 64zn 114sn

  1. Evaluation of Excitation Function for 64Zn

    Institute of Scientific and Technical Information of China (English)

    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

  2. Thermal quantities of 46Ti

    Science.gov (United States)

    Rahmatinejad, A.; Razavi, R.; Kakavand, T.

    2015-07-01

    Thermodynamic quantities of 46Ti 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.

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

    CERN Document Server

    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.

  4. Thermal quantities of {sup 46}Ti

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Indian Academy of Sciences (India)

    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.

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

    Indian Academy of Sciences (India)

    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.

  7. MICROSTRUCTURES AND PROPERTIES OF RECIPROCATINGLY EXTRUDED Mg-6.4Zn-1.IY ALLOYS

    Institute of Scientific and Technical Information of China (English)

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

    2008-01-01

    An icosahedral Mg3 YZn6 quasicrystalline phase can be produced in Mg-Zn-Y system alloys when a proper amount of Zn and Y is contained, and it is feasible to prepare the quasicrystal phase-reinforced low-density magnesium alloy. In this article, phase constituents and the effect of reciprocating extrusion on microstructures and properties of the as-cast Mg-6.4Zn-1.1 Y alloy are analyzed. The microstructure of the as-cast Mg-6.4Zn-1.1 Y alloy consists of the a-Mg solid solution, icosahedral Mg3 YZn6 quasicrystal, and Mg3 Y2Zn3 and MgZn2 compounds. After the alloy was reciprocatingly extruded for four passes, grains were refined, Mg3 Y2 Zn3 and MgZn2 phases dissolved into the matrix, whereas, Mg3YZn6 precipitated and distributed uniformly. The alloy possesses the best performance at this state; the tensile strength, yield strength, and elongation are 323.4 MPa, 258.2 MPa, and 19.7%, respectively. In comparison with that of the as-cast alloy, the tensile strength, yield strength, and elongation of the reciprocatingly extruded alloy increase by 258.3%, 397.5%, and 18 times, respectively. It is concluded that reciprocating extrusion can substantially improve the properties of the as-cast Mg-6.4Zn-1.1 Y alloy, particularly for elongation. The high performance of the Mg-6.4Zn-1.1 Y alloy after reciprocating extrusion can be attributed to dispersion strengthening and grain-refined microstructures.

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

    CERN Multimedia

    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.

  9. Statistical model analysis of α -induced reaction cross sections of 64Zn at low energies

    Science.gov (United States)

    Mohr, P.; Gyürky, Gy.; Fülöp, Zs.

    2017-01-01

    Background: α -nucleus potentials play an essential role in the calculation of α -induced reaction cross sections at low energies in the statistical model. Uncertainties of these calculations are related to ambiguities in the adjustment of the potential parameters to experimental elastic scattering angular distributions (typically at higher energies) and to the energy dependence of the effective α -nucleus potentials. Purpose: The present work studies cross sections of α -induced reactions for 64Zn at low energies and their dependence on the chosen input parameters of the statistical model calculations. The new experimental data from the recent Atomki experiments allow for a χ2-based estimate of the uncertainties of calculated cross sections at very low energies. Method: Recently measured data for the (α ,γ ), (α ,n ), and (α ,p ) reactions on 64Zn are compared to calculations in the statistical model. A survey of the parameter space of the widely used computer code talys is given, and the properties of the obtained χ2 landscape are discussed. Results: The best fit to the experimental data at low energies shows χ2/F ≈7.7 per data point, which corresponds to an average deviation of about 30% between the best fit and the experimental data. Several combinations of the various ingredients of the statistical model are able to reach a reasonably small χ2/F , not exceeding the best-fit result by more than a factor of 2. Conclusions: The present experimental data for 64Zn in combination with the statistical model calculations allow us to constrain the astrophysical reaction rate within about a factor of 2. However, the significant excess of χ2/F of the best fit from unity demands further improvement of the statistical model calculations and, in particular, the α -nucleus potential.

  10. α scattering and α -induced reaction cross sections of 64Zn at low energies

    Science.gov (United States)

    Ornelas, A.; Mohr, P.; Gyürky, Gy.; Elekes, Z.; Fülöp, Zs.; Halász, Z.; Kiss, G. G.; Somorjai, E.; Szücs, T.; Takács, M. P.; Galaviz, D.; Güray, R. T.; Korkulu, Z.; Özkan, N.; Yalçın, C.

    2016-11-01

    Background: α -nucleus potentials play an essential role for the calculation of α -induced reaction cross sections at low energies in the statistical model. Uncertainties of these calculations are related to ambiguities in the adjustment of the potential parameters to experimental elastic scattering angular distributions and to the energy dependence of the effective α -nucleus potentials. Purpose: The present work studies the total reaction cross section σreac of α -induced reactions at low energies which can be determined from the elastic scattering angular distribution or from the sum over the cross sections of all open nonelastic channels. Method: Elastic and inelastic 64Zn(α ,α )64Zn angular distributions were measured at two energies around the Coulomb barrier, at 12.1 and 16.1 MeV. Reaction cross sections of the (α ,γ ) , (α ,n ) , and (α ,p ) reactions were measured at the same energies using the activation technique. The contributions of missing nonelastic channels were estimated from statistical model calculations. Results: The total reaction cross sections from elastic scattering and from the sum of the cross sections over all open nonelastic channels agree well within the uncertainties. This finding confirms the consistency of the experimental data. At the higher energy of 16.1 MeV, the predicted significant contribution of compound-inelastic scattering to the total reaction cross section is confirmed experimentally. As a by-product it is found that most recent global α -nucleus potentials are able to describe the reaction cross sections for 64Zn around the Coulomb barrier. Conclusions: Total reaction cross sections of α -induced reactions can be well determined from elastic scattering angular distributions. The present study proves experimentally that the total cross section from elastic scattering is identical to the sum of nonelastic reaction cross sections. Thus, the statistical model can reliably be used to distribute the total reaction

  11. Long-range dynamic polarization potentials for 11Be projectiles on 64Zn

    Science.gov (United States)

    So, W. Y.; Kim, K. S.; Choi, K. S.; Cheoun, Myung-Ki

    2015-07-01

    We investigate the effects of the long-range dynamic polarization (LRDP) potential, which consists of the Coulomb dipole excitation (CDE) potential and the long-range nuclear (LRN) potential, for the 11Be projectile on 64Zn. To study these effects, we perform a χ2 analysis of an optical model including the LRDP potential as well as a conventional short-range nuclear (SRN) potential. To take these effects into account, we argue that both the CDE and LRN potentials are essential to explaining the experimental values of PE, which is the ratio of the elastic scattering cross section to the Rutherford cross section. The Coulomb and nuclear parts of the LRDP potential are found to contribute to a strong absorption effect. Strong absorption occurs because the real part of the CDE and LRN potentials lowers the barrier, and the imaginary part of the CDE and LRN potentials removes the flux from the elastic channel in the 11Be+64Zn system. Finally, we extract the total reaction cross section σR including the inelastic, breakup, and fusion cross sections. The contribution of the inelastic scattering by the first excited state at ɛx1 st=0.32 MeV (1 /2-) is found to be relatively large and cannot be ignored. In addition, our results are shown to agree quite well with the experimental breakup reaction cross section by using a fairly large radius parameter.

  12. $\\alpha$-scattering and $\\alpha$-induced reaction cross sections of $^{64}$Zn at low energies

    CERN Document Server

    Ornelas, A; Gyürky, Gy; Elekes, Z; Fülöp, Zs; Halász, Z; Kiss, G G; Somorjai, E; Szücs, T; Takács, M P; Galaviz, D; Güray, R T; Korkulu, Z; Özkan, N; Yalçın, C

    2016-01-01

    Background: alpha-nucleus potentials play an essential role for the calculation of alpha-induced reaction cross sections at low energies in the statistical model... Purpose: The present work studies the total reaction cross section sigma_reac of alpha-induced reactions at low energies which can be determined from the elastic scattering angular distribution or from the sum over the cross sections of all open non-elastic channels. Method: Elastic and inelastic 64Zn(a,a)64Zn angular distributions were measured at two energies around the Coulomb barrier at 12.1 MeV and 16.1 MeV. Reaction cross sections of the (a,g), (a,n), and (a,p) reactions were measured at the same energies using the activation technique. The contributions of missing non-elastic channels were estimated from statistical model calculations. Results: The total reaction cross sections from elastic scattering and from the sum of the cross sections over all open non-elastic channels agree well within the uncertainties. This finding confirms the cons...

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

    CERN Document Server

    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.

  14. Heavy-ion fusion cross sections of weakly bound {sup 9}Be on {sup 27}Al, {sup 64}Zn and tightly bound {sup 16}O on {sup 64}Zn target using Coulomb and proximity potential

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, K.P., E-mail: drkpsanthosh@gmail.com; Bobby Jose, V.

    2014-02-15

    The total fusion cross sections for the fusion of weakly bound {sup 9}Be on {sup 27}Al and {sup 64}Zn targets at near and above the barrier have been calculated using one dimensional barrier penetration model, taking scattering potential as the sum of Coulomb and proximity potential and the calculated values are compared with experimental data. For the purpose of comparison of the fusion of weakly bound projectiles and strongly bound projectiles, the total fusion cross sections for the reaction of tightly bound nucleus {sup 16}O on {sup 64}Zn have also been computed using a similar procedure. The calculated values of total fusion cross sections in all cases are compared with coupled channel calculations using the code CCFULL. The computed cross sections using Coulomb and proximity potential explain the fusion reactions well in both cases of weakly bound and strongly bound projectiles. Reduced reaction cross sections for the systems {sup 9}Be+{sup 27}Al, {sup 9}Be+{sup 64}Zn and {sup 16}O+{sup 64}Zn have also been described.

  15. Heavy-ion fusion cross sections of weakly bound $^{9}$Be on $^{27}$Al, $^{64}$Zn and tightly bound $^{16}$O on $^{64}$Zn target using Coulomb and proximity potential

    CERN Document Server

    Santhosh, K P

    2013-01-01

    The total fusion cross sections for the fusion of weakly bound $^{9}$Be on $^{27}$Al and $^{64}$Zn targets at near and above the barrier have been calculated using one dimensional barrier penetration model, taking scattering potential as the sum of Coulomb and proximity potential and the calculated values are compared with experimental data. For the purpose of comparison of the fusion of weakly bound projectiles and strongly bound projectiles, the total fusion cross sections for the reaction of tightly bound nucleus $^{16}$O on $^{64}$Zn have also been computed using a similar procedure. The calculated values of total fusion cross sections in all cases are compared with coupled channel calculations using the code CCFULL. The computed cross sections using Coulomb and proximity potential explain the fusion reactions well in both cases of weakly bound and strongly bound projectiles. Reduced reaction cross sections for the systems $^{9}$Be + $^{27}$Al, $^{9}$Be+ $^{64}$Zn and $^{16}$O + $^{64}$Zn have also been d...

  16. Cyclotron production of {sup 64}Cu by deuteron irradiation of {sup 64}Zn

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, K. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (Vatican City State, Holy See,) (Italy)]. E-mail: kamel.abbas@jrc.it; Kozempel, J. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Charles University Prague, Faculty of Science, Department of Organic and Nuclear Chemistry, 128 43 Prague (Czech Republic); Bonardi, M. [LASA, Radiochemistry Laboratory, University and INFN, via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Groppi, F. [LASA, Radiochemistry Laboratory, University and INFN, via F.lli Cervi 201, I-20090 Segrate (MI) (Italy); Alfarano, A. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Holzwarth, U. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Simonelli, F. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Hofman, H. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Horstmann, W. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy); Menapace, E. [ENEA, Applied Physics Division, Bologna (Italy); Leseticky, L. [Charles University Prague, Faculty of Science, Department of Organic and Nuclear Chemistry, 128 43 Prague (Czech Republic); Gibson, N. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, TP 500, I-21020 Ispra (VA) (Italy)

    2006-09-15

    The short-lived (12.7 h half-life) {sup 64}Cu radioisotope is both a {beta} {sup +} and a {beta} {sup -} emitter. This property makes {sup 64}Cu a promising candidate for novel medical applications, since it can be used simultaneously for therapeutic application of radiolabelled biomolecules and for diagnosis with PET. Following previous work on {sup 64}Cu production by deuteron irradiation of natural zinc, we report here the production of this radioisotope by deuteron irradiation of enriched {sup 64}Zn. In addition, yields of other radioisotopes such as {sup 61}Cu, {sup 67}Cu, {sup 65}Zn, {sup 69m}Zn, {sup 66}Ga and {sup 67}Ga, which were co-produced in this process, were also measured. The evaporation code ALICE-91 and the transport code SRIM 2003 were used to determine the excitation functions and the stopping power, respectively. All the nuclear reactions yielding the above-mentioned radioisotopes were taken into account in the calculations both for the natural and enriched Zn targets. The experimental and calculated yields were shown to be in reasonable agreement. The work was carried out at the Scanditronix MC-40 Cyclotron of the Institute for Health and Consumer Protection of the Joint Research Centre of the European Commission (Ispra site, Italy). The irradiations were carried out with 19.5 MeV deuterons, the maximum deuteron energy obtainable with the MC-40 cyclotron.

  17. Strong Deformation Effects in Hot Rotating 46Ti

    CERN Document Server

    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.

  18. Structure effects in the reactions {sup 9,10,11}Be+{sup 64}Zn at the Coulomb barrier

    Energy Technology Data Exchange (ETDEWEB)

    Scuderi, V; Amorini, F; Fisichella, M; Lattuada, M; Pellegriti, M G; Randisi, G; Rizzo, F [Dipartimento di Fisica ed Astronomia Universita di Catania, Catania (Italy); Pietro, A Di; Figuera, P; Musumarra, A; Papa, M [INFN-Laboratori Nazionali del Sud and Sezione di Catania (Italy); Acosta, L; Martel, I; Perez-Bernal, F [Departamento de Fisica Aplicada Universidad de Huelva, Huelva (Spain); Borge, M J G [Instituto de Estructura de la Materia CSIC, Madrid (Spain); Fraile, L M; Jeppesen, H [CERN, Geneva (Switzerland); Gomez-Camacho, J [Departamento de Fisica Atomica Molecular Nuclear Universidad de Sevilla, Sevilla (Spain); Milin, M [Department of Physics Faculty of Science University of Zagreb, Zagreb (Croatia); Raabe, R, E-mail: scuderiv@lns.infn.it [Instituut voor Kern-en Stralingsfysica University of Leuven, Leuven (Belgium)

    2011-01-01

    Elastic scattering and direct reactions have been studied for the collisions induced by the three Beryllium isotopes {sup 9,10,11}Be, on a medium mass {sup 64}Zn target at energies around the Coulomb barrier. The elastic scattering angular distributions, measured for the three systems at the same center of mass energy, were analyzed within the Optical Model and reaction cross-sections were deduced from optical model calculations. For the {sup 11}Be induced reaction the transfer/break-up angular distribution was also extracted.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.}

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

    Indian Academy of Sciences (India)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  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

    Energy Technology Data Exchange (ETDEWEB)

    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. Search for 2{beta} processes in {sup 64}Zn with the help of ZnWO{sub 4} crystal scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Belli, P. [Dipartimento di Fisica, Universita di Roma ' Tor Vergata' and INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy); Bernabei, R. [Dipartimento di Fisica, Universita di Roma ' Tor Vergata' and INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy)], E-mail: rita.bernabei@roma2.infn.it; Cappella, F. [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, I-00185 Rome (Italy); Cerulli, R. [INFN, Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ) (Italy); Dai, C.J. [IHEP, Chinese Academy, P.O. Box 918/3, Beijing 100039 (China); Danevich, F.A. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Grinyov, B.V. [Institute for Scintillation Materials, 61001 Kharkiv (Ukraine); Incicchitti, A. [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, I-00185 Rome (Italy); Kobychev, V.V. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Nagornaya, L.L. [Institute for Scintillation Materials, 61001 Kharkiv (Ukraine); Nagorny, S.S. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Nozzoli, F. [Dipartimento di Fisica, Universita di Roma ' Tor Vergata' and INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy); Poda, D.V. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Prosperi, D. [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, I-00185 Rome (Italy); Tretyak, V.I.; Yurchenko, S.S. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine)

    2008-01-10

    Double beta processes in {sup 64}Zn were searched for with the help of a low background ZnWO{sub 4} crystal scintillator (mass of 117 g) at the Gran Sasso National Laboratories of the INFN. Total time of measurements was 1902 h. New improved half-life limits on different modes of double electron capture and electron capture with positron emission were established as: T{sub 1/2}{sup 2{nu}}{sup 2K}{>=}6.2x10{sup 18} yr, T{sub 1/2}{sup 0{nu}}{sup 2K}{>=}4.0x10{sup 18} yr, T{sub 1/2}{sup 0{nu}}{sup 2{epsilon}}{>=}3.4x10{sup 18} yr, T{sub 1/2}{sup 2{nu}}{sup {epsilon}}{sup {beta}{sup +}}{>=}2.1x10{sup 20} yr, and T{sub 1/2}{sup 0{nu}}{sup {epsilon}}{sup {beta}{sup +}}{>=}2.2x10{sup 20} yr, all at 90% C.L.

  4. Search for the Jacobi Instability in Rapidly Rotating 46Ti* Nuclei

    CERN Document Server

    Maj, A; Krolas, W; Styczen, J; Bracco, A; Camera, F; Million, B; Gaardhøje, J J; Herskind, B; Kicinska-Habior, M; Kownacki, J P; Ormand, W E

    2001-01-01

    The possible existence of Jacobi shape transition in hot 46Ti at high angular momenta was investigated with the Giant Dipole Resonance exclusive experiments. The GDR spectra and the angular distributions are consistent with predictions of the thermal shape fluctuation model indicating elongated nuclear shapes.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.).

  6. Study of Deformation Effects in the Charged Particle Emission from 46Ti

    CERN Document Server

    Brekiesz, M; Maj, A; Kmiecik, M; Beck, C; Bednarczyk, P; Grebosz, J; Haas, F; Meczynski, W; Rauch, V; Rousseau, M; Zafra, A S; Styczen, J; Thummerer, S; Zieblinski, M; Zuber, K

    2004-01-01

    The 46Ti compound nucleus, as populated by the fusion-evaporation reaction 27Al + 19F at the bombarding energy of 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 have been measured in coincidence with 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 spectra. This comparison indicates the possible signature of large deformations of the compound nucleus.

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

    CERN Document Server

    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...

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

    Science.gov (United States)

    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.

  9. Copper doping of ZnO crystals by transmutation of {sup 64}Zn to {sup 65}Cu: An electron paramagnetic resonance and gamma spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Recker, M. C.; McClory, J. W., E-mail: John.McClory@afit.edu; Holston, M. S.; Golden, E. M.; Giles, N. C. [Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433 (United States); Halliburton, L. E. [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2014-06-28

    Transmutation of {sup 64}Zn to {sup 65}Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the {sup 65}Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of {sup 64}Zn nuclei to {sup 65}Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu{sup 2+} ions (where {sup 63}Cu and {sup 65}Cu hyperfine lines are easily resolved). A spectrum from isolated Cu{sup 2+} (3d{sup 9}) ions acquired after the neutron irradiation showed only hyperfine lines from {sup 65}Cu nuclei. The absence of {sup 63}Cu lines in this Cu{sup 2+} spectrum left no doubt that the observed {sup 65}Cu signals were due to transmuted {sup 65}Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu{sup +}-H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu{sup +}-H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900 °C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. The study of the components of matter collective flow in the collisions of {sup 64} Zn on {sup 58} Ni at 35 to 79 MeV/u; Etude des composantes de l`ecoulement collectif de matiere dans les collisions {sup 64} Zn sur {sup 58} Ni de 35 a 79 MeV/u

    Energy Technology Data Exchange (ETDEWEB)

    Popescu, R. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire

    1995-06-01

    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 {sup 64} Zn on {sup 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) 37 refs.

  13. Deformation Effects in Hot Rotating $^{46}Ti$ Probed by the Charged Particle Emission and GDR $\\gamma-Decay$

    CERN Document Server

    Brekiesz, M; Kmiecik, M; Mazurek, K; Meczynski, W; Styczen, J; Zuber, K; Papka, P; Beck, C; Haas, F; Rauch, V; Rousseau, M; Zafra, A S; Dudek, J; Schunck, N

    2007-01-01

    The 46Ti* compound nucleus, as populated by the fusion-evaporation reaction 27Al+19F at the bombarding energy of E_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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Origin of the DOS pseudogap and Hume-Rothery stabilization mechanism in RT-type Al48Mg64Zn48 and Al84Li52Cu24 1/1-1/1-1/1 approximants

    Science.gov (United States)

    Inukai, M.; Zijlstra, E. S.; Sato, H.; Mizutani, U.

    2011-11-01

    Full-potential linearized plane wave (FLAPW) band calculations with subsequent FLAPW-Fourier analyses have been performed for two RT-type Al48Mg64Zn48 and Al84Li52Cu24 1/1-1/1-1/1 approximants containing 160 atoms per unit cell. The FLAPW-Fourier analysis revealed that the Fermi surface-Brillouin zone (FsBz) interactions involving more than two sets of lattice planes are responsible for the formation of a pseudogap across the Fermi level in both compounds. The most critical sets of lattice planes interfering with electrons at the Fermi level are deduced to be {543} + {710} + {550} with ? = 50 in the former and {631} with ? = 46 in the latter. The square of the Fermi diameter ? is determined to be 49.9 ± 0.1 and 47.1 ± 0.4 in units of ? , respectively, where a is the lattice constant. Hence, the matching condition ? holds well in both compounds. It is also shown that, while a shallow pseudogap in the Al48Mg64Zn48 approximant can be ascribed solely to the FsBz interactions, a much deeper one in the Al84Li52Cu24 approximant is explained as a superposition of the FsBz interactions and the formation of strongly directional bonding states between Cu-4p and Al-3p orbitals.

  16. From in-plane to out-of-plane enhancement of the directed flow in {sup 64}Zn on {sup 58}Ni collisions between 35 and 79 MeV/u

    Energy Technology Data Exchange (ETDEWEB)

    Angelique, J.C.; Bizard, G.; Brou, R.; Cussol, D.; Kerambrun, A.; Patry, J.P.; Peter, J.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire; Popescu, R.; Buta, A. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire]|[Central Inst. of Physics, Bucharest (Romania). Inst. of Physics and Nuclear Engineering; He, Z.Y. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire]|[Lanzhou Univ., GS (China). Dept. of Modern Physics; Auger, G.; Peghaire, A.; Saint-Laurent, F. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Cabot, C. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France)]|[Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; Crema, E. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France)]|[Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Hagel, K.; Wada, R. [Texas A and M Univ., College Station, TX (United States). Cyclotron Inst.; Gonin, M. [Texas A and M Univ., College Station, TX (United States). Cyclotron Inst.]|[Brooklyn Coll., NY (United States). Dept. of Chemistry; Eudes, P.; Lebrun, C. [Nantes Univ., 44 (France). Lab. de Physique Nucleaire; El Masri, Y. [Universite Catholique de Louvain (UCL), Louvain-la-Neuve (Belgium); Rosato, E. [Istituto Nazionale di Fisica Nucleare, Naples (Italy)

    1994-05-01

    The azimuthal distributions of light particles relative to the reaction plane have been measured for several bins of experimentally estimated impact parameter in the reactions of {sup 64}Zn + {sup 58}Ni at energies between 35 and 79 MeV/u. An in-plane enhancement for mid-rapidity Z = 1, 2, 3 particles is observed at low incident energy but gradually evolves to out-of plane enhancement (squeeze-out effect) with increasing energy. This evolution depends on the impact parameter in a way similar to the flow parameter. The energies for this system at which the azimuthal distribution is uniform are lower than the corresponding balance energies. (authors). 22 refs.

  17. Isospin Against Size Effects In Projectile Dynamical Fission For 112,124Sn+58,64Ni and 124Xe+64Zn Reactions At 35 A.MeV

    Science.gov (United States)

    Russotto, P.; De Filippo, E.; Pagano, A.; Piasecki, E.; Acosta, L.; Amorini, F.; Anzalone, A.; Auditore, L.; Baran, V.; Berceanu, I.; Boiano, C.; Borderie, B.; Bruno, M.; Cap, T.; Cardella, G.; Castoldi, A.; Cavallaro, S.; Chatterjee, M. B.; Chbihi, A.; Colonna, M.; D'Agostino, M.; D'Andrea, M.; Di Toro, M.; Fichera, F.; Francalanza, L.; Geraci, E.; Gianì, R.; Gnoffo, B.; Grimaldi, A.; Grzeszczuk, A.; Guazzoni, C.; Guazzoni, P.; Giudice, N.; Kowalski, S.; La Guidara, E.; Lanzalone, G.; Lanzanò, G.; Lombardo, I.; Maiolino, C.; Marquínez-Durán, G.; Minniti, T.; Papa, M.; Pagano, E. V.; Passaro, G.; Pirrone, S.; Płaneta, R.; Politi, G.; Porto, F.; Quattrocchi, L.; Rivet, M. F.; Rosato, E.; Riccio, F.; Rizzo, F.; Saccà, G.; Schmidt, K.; Siwek-Wilczyńska, K.; Skwira-Chalot, I.; Trifirò, A.; Trimarchi, M.; Verde, G.; Vigilante, M.; Wieleczko, J. P.; Wilczyński, J.; Zambon, P.; Zetta, L.; Zipper, W.

    2014-05-01

    In past experiments, mass asymmetric projectile-target combinations124Sn+64Ni and 112Sn+58Ni were investigated at ELab(112'124Sn)=35 A.MeVbeam energybyusing the 4n multi-detector CHIMERA. From a quantitative comparison of cross sections associated to Statistical and Dynamical Fission of the Projectile-Like Fragments, it resulted that Dynamical Fission process is about two times more probable in the neutron rich 124Sn+64Ni system than in the 112 Sn +58 Ni neutron poor one. In contrast, no sizable difference was found for Statistical Fission mechanism. The observed difference in the strength of the Dynamical effects could arise from the difference in entrance channel Isospin (N/Z) content. In order to disentangle Isospin effects from effects due to the different masses of the two systems, a new experiment 124Xe+64Zn at 35 A.MeV beam energy has been recently carried out.

  18. Ab initio study on vibrational dipole moments of XH{sup +} molecular ions: X = {sup 24}Mg, {sup 40}Ca, {sup 64}Zn, {sup 88}Sr, {sup 114}Cd, {sup 138}Ba, {sup 174}Yb and {sup 202}Hg

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Minori; Hada, Masahiko [Department of Chemistry, Tokyo Metropolitan University, 1-1, Minami-Osawa, Hachioji, Tokyo 192-0397 (Japan); Kajita, Masatoshi [National Institute of Information and Communications Technology, Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan); Moriwaki, Yoshiki, E-mail: minoria@tmu.ac.j [Department of Physics, University of Toyama, Gofuku, Toyama, 930-8555 (Japan)

    2010-12-28

    The vibrational matrix elements of electric dipole moments were theoretically estimated for the electronic ground state of XH{sup +} molecular ions (X = {sup 24}Mg, {sup 40}Ca, {sup 64}Zn, {sup 88}Sr, {sup 114}Cd, {sup 138}Ba, {sup 174}Yb and {sup 202}Hg) using the complete active space second-order perturbation theory method. Because of the large rotational constant and zero X-nuclear spin, these molecules are advantageous to be localized to a single (v, J, F) state, where v, J, F are quantum numbers of the vibrational, rotational and hyperfine states, respectively. The information of the dipole moments is very useful to discuss the period to localize the molecular ion to the (v, J, F) = (0, 0, 1/2) state and also the period to remain in this state, which is limited by the interaction with the black body radiation. The agreement of experimental and our theoretical spectroscopic constants ensures the accuracy of our results. Vibrational permanent and transition dipole moments were obtained with special care of accuracy in numerical integration. Spontaneous emission rates were calculated from the vibrational dipole moments and transition energies.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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%.

  1. Ferroelectromagnetic solid solutions on the base piezoelectric ceramic materials for components of micromechatronics

    Science.gov (United States)

    Bochenek, Dariusz; Zachariasz, Radosław; Niemiec, Przemysław; Ilczuk, Jan; Bartkowska, Joanna; Brzezińska, Dagmara

    2016-10-01

    In the presented work, a ferroelectromagnetic solid solutions based on PZT and ferrite powders have been obtained. The main aim of combination of ferroelectric and magnetic powders was to obtain material showing both electric and magnetic properties. Ferroelectric ceramic powder (in amount of 90%) was based on the doped PZT type solid solution while magnetic component was nickel-zinc ferrite Ni1-xZnxFe2O4 (in amount of 10%). The synthesis of components of ferroelectromagnetic solid solutions was performed using the solid phase sintering. Final densification of synthesized powder has been done using free sintering. The aim of the work was to obtain and examine in the first multicomponent PZT type ceramics admixed with chromium with the following chemical composition Pb0.94Sr0.06(Zr0.46Ti0.54)O3+0.25 at% Cr2O3 and next ferroelectromagnetic solid solution based on a PZT type ferroelectric powder (Pb0.94Sr0.06(Zr0.46Ti0.54)O3+0.25 at% Cr2O3) and nickel-zinc ferrite (Ni0.64Zn0.36Fe2O4), from the point of view of their mechanical and electric properties, such as: electric permittivity, ε; dielectric loss, tanδ; mechanical losses, Q-1; and Young modulus, E.

  2. The PSIMECX medium-energy neutron activation cross-section library. Part II: Calculational methods for light to medium mass nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Atchison, F.

    1998-09-01

    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: {sup 12}C, {sup 13}C, {sup 16}O, {sup 17}O, {sup 18}O, {sup 23}Na, {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 27}Al, {sup 28}Si, {sup 29}Si, {sup 30}Si, {sup 31}P, {sup 32}S, {sup 33}S, {sup 34}S, {sup 36}S, {sup 35}Cl, {sup 37}Cl, {sup 39}K, {sup 40}K, {sup 41}K, {sup 40}Ca, {sup 42}Ca, {sup 43}Ca, {sup 44}Ca, {sup 46}Ca, {sup 48}Ca, {sup 46}Ti, {sup 47}Ti, {sup 48}Ti, {sup 49}Ti, {sup 50}Ti, {sup 50}V, {sup 51}V, {sup 50}Cr, {sup 52}Cr, {sup 53}Cr, {sup 54}Cr, {sup 55}Mn, {sup 54}Fe, {sup 56}Fe, {sup 57}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 61}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 66}Zn, {sup 67}Zn, {sup 68}Zn, {sup 70}Zn, {sup 92}Mo, {sup 94}Mo, {sup 95}Mo, {sup 96}Mo, {sup 97}Mo, {sup 98}Mo, {sup 100}Mo, {sup 121}Sb, {sup 123}Sb, {sup 204}Pb, {sup 206}Pb, {sup 207}Pb, {sup 208}Pb, {sup 232}Th and {sup 238}U. 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 second report, of a series of three, describes and discusses the calculational methods used for the stable isotopes up to and including {sup 123}Sb. The library itself has been described in the first report of the series and the treatment for the heavy nuclei is given in the third. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Atchison, F.

    1998-09-01

    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: {sup 12}C, {sup 13}C, {sup 16}O, {sup 17}O, {sup 18}O, {sup 23}Na, {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 27}Al, {sup 28}Si, {sup 29}Si, {sup 30}Si, {sup 31}P, {sup 32}S, {sup 33}S, {sup 34}S, {sup 36}S, {sup 35}Cl, {sup 37}Cl, {sup 39}K, {sup 40}K, {sup 41}K, {sup 40}Ca, {sup 42}Ca, {sup 43}Ca, {sup 44}Ca, {sup 46}Ca, {sup 48}Ca, {sup 46}Ti, {sup 47}Ti, {sup 48}Ti, {sup 49}Ti, {sup 50}Ti, {sup 50}V, {sup 51}V, {sup 50}Cr, {sup 52}Cr, {sup 53}Cr, {sup 54}Cr, {sup 55}Mn, {sup 54}Fe, {sup 56}Fe, {sup 57}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 61}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 66}Zn, {sup 67}Zn, {sup 68}Zn, {sup 70}Zn, {sup 92}Mo, {sup 94}Mo, {sup 95}Mo, {sup 96}Mo, {sup 97}Mo, {sup 98}Mo, {sup 100}Mo, {sup 121}Sb, {sup 123}Sb, {sup 204}Pb, {sup 206}Pb, {sup 207}Pb, {sup 208}Pb, {sup 232}Th and {sup 238}U. 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)

  4. Precise measurement of energies in 115Sn following the (n ,γ ) reaction

    Science.gov (United States)

    Urban, W.; Köster, U.; Jentschel, M.; Mutti, P.; Märkisch, B.; RzÄ ca-Urban, T.; Bernards, Ch.; Fransen, Ch.; Jolie, J.; Thomas, T.; Simpson, G. S.

    2016-07-01

    The first measurement of γ rays from the 114Sn(n ,γ ) reaction using cold neutrons, performed with an array of Ge detectors at the PF1B facility of the Institute Laue-Langevin in Grenoble, has provided the most accurate energy, Qβ=173 (12 ) eV, of β- decay of the 115In ground state to the first excited state in 115Sn. This is the lowest of all such energies in the known nuclear landscape. The accuracy of the neutron binding energy of 115Sn and the mass of 114Sn have been improved.

  5. Neutron activation of natural zinc samples at kT = 25 keV

    OpenAIRE

    Reifarth, R.; Dababneh, S.; Heil, M.; Käppeler, F.; Plag, R.; Sonnabend, K.; Uberseder, E.

    2013-01-01

    The neutron-capture cross sections of 64Zn, 68Zn, and 70Zn have been measured with the activation technique in a quasistellar neutron spectrum corresponding to a thermal energy of kT = 25 keV. By a series of repeated irradiations with different experimental conditions, an uncertainty of 3% could be achieved for the 64Zn(n,g)65Zn cross section and for the partial cross section 68Zn(n,g)69Zn-m feeding the isomeric state in 69Zn. For the partial cross sections 70Zn(n,g)71Zn-m and 70Zn(n,g)71Zn-g...

  6. Search for double beta decay of zinc and tungsten with low background ZnWO{sub 4} crystal scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Bernabei, R; Nozzoli, F [Dip. di Fisica, Universita di Roma ' Tor Vergata' , I-00133 Rome (Italy); Belli, P [INFN, sez. Roma ' Tor Vergata' , I-00133 Rome (Italy); Cappella, F; Prosperi, D [Dip. di Fisica, Universita di Roma ' La Sapienza' , I-00185 Rome (Italy); Cerulli, R; Nisi, S [INFN, Laboratori Nazionali del Gran Sasso, 67010 Assergi (Italy); Danevich, F A; Kobychev, V V; Mokina, V M; Nagorny, S S; Poda, D V; Tretyak, V I; Yurchenko, S S [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Grinyov, B V; Nagornaya, L L [Institute for Scintillation Materials, 61001 Kharkiv (Ukraine); Incicchitti, A [INFN, sez. Roma, I-00185 Rome (Italy)

    2010-01-01

    Double beta processes in {sup 64}Zn, {sup 70}Zn, {sup 180}W, and {sup 186}W have been searched for with the help of low background ZnWO4 crystal scintillators at the Gran Sasso National Laboratories of the INFN (Italy). The total measurement time exceeds ten thousand hours. New improved half-life (T{sub 1/2}) limits on double electron capture and electron capture with positron emission in {sup 64}Zn have been set. New T{sub 1/2} bounds were also set on different modes of 2{beta} processes in {sup 70}Zn, {sup 180}W, and {sup 186}W. Future perspectives are considered.

  7. High specific activity ⁶¹Cu via ⁶⁴Zn(p,α)⁶¹Cu reaction at low proton energies.

    Science.gov (United States)

    Thieme, Stefan; Walther, Martin; Preusche, Stephan; Rajander, Johan; Pietzsch, Hans-Jürgen; Lill, Jan-Olof; Kaden, Michael; Solin, Olof; Steinbach, Jörg

    2013-02-01

    The PET radionuclide (61)Cu is accessible through several nuclear reactions. Besides the common production route via (61)Ni(p,n)(61)Cu the (64)Zn(p,α)(61)Cu reaction offers some advantages. Especially the comparatively cheap enriched (64)Zn makes this process economical. For fast product purification and recycling of target material an ion exchange cascade was developed. In addition a separation technique with a copper selective resin was tested. (61)Cu with specific activities up to 1000 GBq/μmol was produced with these methods. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Origins of dipole resonance strength fragmentation in calcium and titanium isotopes

    Directory of Open Access Journals (Sweden)

    Skorodumina Iu. A.

    2012-12-01

    Full Text Available Theoretical description of dipole resonances in 46Ti, 48Ti, 50Ti, 48Ca, 40Ca was performed. The distribution of the “hole” among the states of final nuclei was taken into account using information on pick-up reactions. The obtained results are in reasonable agreement with experimental data.

  11. Isospin dependence of physical observables in Incomplete Fusion reactions at 25 MeV/nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Lombardo, I., E-mail: ilombardo@lns.infn.i [Dipartimento di Fisica, Universita di Catania, Catania (Italy); INFN Laboratori Nazionali del Sud, Catania (Italy); Agodi, C.; Alba, R. [INFN Laboratori Nazionali del Sud, Catania (Italy); Amorini, F. [INFN, Sezione di Catania, Catania (Italy); Dipartimento di Fisica, Universita di Catania, Catania (Italy); Anzalone, A. [INFN Laboratori Nazionali del Sud, Catania (Italy); Berceanu, I. [Institute for Physics and Nuclear Engineering, Bucharest (Romania); Cardella, G. [INFN, Sezione di Catania, Catania (Italy); Cavallaro, S. [Dipartimento di Fisica, Universita di Catania, Catania (Italy); INFN Laboratori Nazionali del Sud, Catania (Italy); Chatterjee, M.B. [Saha Institute of Nuclear Physics, Kolkata (India); Coniglione, R. [INFN Laboratori Nazionali del Sud, Catania (Italy); DeFilippo, E. [INFN, Sezione di Catania, Catania (Italy); DiPietro, A.; Figuera, P. [INFN Laboratori Nazionali del Sud, Catania (Italy); Geraci, E.; Giuliani, G.; Grassi, L. [Dipartimento di Fisica, Universita di Catania, Catania (Italy); INFN, Sezione di Catania, Catania (Italy); Grzeszczuk, A. [Institute of Physics, University of Silesia, Katowice (Poland); LaGuidara, E. [INFN, Sezione di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Lanzalone, G. [INFN Laboratori Nazionali del Sud, Catania (Italy); Libera Universita Kore, Enna (Italy); LeNeindre, N. [LPC Caen, CNRS-IN2P3, ENSICAEN, Universite de Caen, Caen (France)

    2010-03-01

    Isospin dependence of dynamical and thermodynamical physical quantities observed in the reactions {sup 40}Ca + {sup 40,48}Ca and {sup 40}Ca + {sup 46}Ti at 25 MeV/nucleon has been analyzed by means of the CHIMERA multi-detector.

  12. Continuum effects in the scattering of exotic nuclei

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  13. Search for double beta decay of Zinc and Tungsten with the help of low-background ZnWO4 crystal scintillators

    CERN Document Server

    Belli, P; Cappella, F; Cerulli, R; Danevich, F A; Grinyov, B V; Incicchitti, A; Kobychev, V V; Mokina, V M; Nagorny, S S; Nagornaya, L L; Nisi, S; Nozzoli, F; Poda, D V; Prosperi, D; Tretyak, V I; Yurchenko, S S

    2008-01-01

    Double beta processes in 64-Zn, 70-Zn, 180-W, and 186-W have been searched for with the help of large volume (0.1-0.7 kg) low background ZnWO4 crystal scintillators at the Gran Sasso National Laboratories of the INFN. Total time of measurements exceeds 10 thousands hours. New improved half-life limits on double electron capture and electron capture with positron emission in 64-Zn have been set, in particular (all the limits are at 90% C.L.): T1/2(0nu2EC)> 1.1e20 yr, T1/2(2nuECbeta+)>7.0e20 yr, and T1/2(0nuECbeta+)>4.3e20 yr. The different modes of double beta processes in 70-Zn, 180-W, and 186-W have been restricted at the level of 1e17-1e20 yr.

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

    CERN Document Server

    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\

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Model-based predictions for nuclear excitation functions of neutron-induced reactions on 64,66−68Zn targets

    Directory of Open Access Journals (Sweden)

    M. Yiğit

    2017-08-01

    Full Text Available In this paper, nuclear data for cross sections of the 64Zn(n,2n63Zn, 64Zn(n,3n62Zn, 64Zn(n,p64Cu, 66Zn(n,2n65Zn, 66Zn(n,p66Cu, 67Zn(n,p67Cu, 68Zn(n,p68Cu, and 68Zn(n,α65Ni reactions were studied for neutron energies up to 40 MeV. In the nuclear model calculations, TALYS 1.6, ALICE/ASH, and EMPIRE 3.2 codes were used. Furthermore, the nuclear data for the (n,2n and (n,p reaction channels were also calculated using various cross-section systematics at energies around 14–15 MeV. The code calculations were analyzed and obtained using the different level densities in the exciton model and the geometry-dependent hybrid model. The results obtained from the excitation function calculations are discussed and compared with literature experimental data, ENDF/B-VII.1, and the TENDL-2015 evaluated data.

  17. Constrained Hartree-Fock Theory and Study of Deformed Structures of Closed Shell Nuclei

    Science.gov (United States)

    Praharaj, Choudhury

    2016-03-01

    We have studied some N or Z = 50 nuclei in a microscopic model with effective interaction in a reasonably large shell model space. Excitation of particles across 50 shell closure leads to well-deformed excited prolate configurations. The potential energy surfaces of nuclei are studied using Hartree-Fock theory with quadrupole constraint to explore the various deformed configurations of N = 50 nuclei 82Ge , 84Se and 86Kr . Energy spectra are calculated from various intrinsic states using Peierls-Yoccoz angular momentum projection technique. Results of spectra and electromagnetic moments and transitions will be presented for N = 50 nuclei and for Z = 50 114Sn nucleus. Supported by Grant No SB/S2/HEP-06/2013 of DST.

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

    CERN Document Server

    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

  19. Search for the Jacobi shape transition in light nuclei

    CERN Document Server

    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.

  20. Search for the Jacobi shape transition in light nuclei

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  1. Do light nuclei display a universal γ-ray strength function?

    Directory of Open Access Journals (Sweden)

    Voinov A.

    2012-02-01

    Full Text Available In this work we focus on properties in the quasi-continuum of light nuclei. Generally, both level density and γ-ray strength function (γ-SF differ from nucleus to nucleus. In order to investigate this closer, we have performed particle-γ coincidences using the reactions (p, p', (p, d and (p, t on a 46Ti target. In particular, the very rich data set of the 46Ti(p, p'46Ti inelastic scattering reaction allows analysis of the coincidence data for many independent data sets. Using the Oslo method, we find one common level density for all data sets. If transitions to well-separated low-energy levels are included, the deduced γ-SF may change by a factor of 2 – 3, due strong to Porter-Thomas fluctuations. However, a universal γ-SF with small fluctuations is found provided that only excitation energies above 3 MeV are taken into account. The nuclear structure of the titaniums is discussed within a combinatorial quasi-particle model, showing that only few Nilsson orbitals participate in building up the level density for these light nuclei.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  6. Chromatographic zinc isotope separation by phenol formaldehyde benzo crown resin.

    Science.gov (United States)

    Ding, Xingcheng; Nomura, Masao; Suzuki, Tatsuya; Sugiyama, Yuichi; Kaneshiki, Toshitaka; Fujii, Yasuhiko

    2006-04-28

    New types of phenol formaldehyde resin having benzo crown as a functional group were synthesized and applied to zinc isotope chromatographic operation. Zinc adsorption and isotope separation capacities were dramatically improved by using phenol formaldehyde benzo-15-crown-5 resin. Zinc batch adsorption tests were performed by various dehydrated organic solvents. Separation coefficient, epsilon 8.1 x 10(-4) and height equivalent to a theoretical plate (HETP) 0.105 cm for the isotopic pair of 68Zn/64Zn in phenol formaldehyde benzo-15-crown-5 resin were obtained in the case of acetone as the solvent at 298+/-1K.

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

    CERN Document Server

    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\

  8. Giant Dipole Resonance in the Hot and Thermalized Ce132 Nucleus: Damping of Collective Modes at Finite Temperature

    Science.gov (United States)

    Wieland, O.; Bracco, A.; Camera, F.; Benzoni, G.; Blasi, N.; Brambilla, S.; Crespi, F.; Giussani, A.; Leoni, S.; Mason, P.; Million, B.; Moroni, A.; Barlini, S.; Kravchuk, V. L.; Gramegna, F.; Lanchais, A.; Mastinu, P.; Maj, A.; Brekiesz, M.; Kmiecik, M.; Bruno, M.; Geraci, E.; Vannini, G.; Casini, G.; Chiari, M.; Nannini, A.; Ordine, A.; Ormand, E.

    2006-07-01

    The γ decay of the giant dipole resonance (GDR) in the Ce132 compound nucleus with temperature up to ≈4MeV has been measured, using the reaction Ni64+Zn68 at Ebeam=300, 400, and 500 MeV. The γ and charged particles measured in coincidence with recoils are consistent with a fully equilibrated compound nucleus emission. The GDR width, obtained with the statistical model analysis, is found to increase almost linearly with temperature. This increase is rather well reproduced within a model including thermal shape fluctuations and the lifetime of the compound nucleus.

  9. Radioactivity-synchronized fluorescence enhancement using a radionuclide fluorescence-quenched dye.

    Science.gov (United States)

    Berezin, Mikhail Y; Guo, Kevin; Teng, Bao; Edwards, W Barry; Anderson, Carolyn J; Vasalatiy, Olga; Gandjbakhche, Amir; Griffiths, Gary L; Achilefu, Samuel

    2009-07-08

    We demonstrate the first evidence of radioactivity-synchronized fluorescence quenching of a near-infrared light-emitting dye by a radionuclide, (64)Cu, and subsequent fluorescence enhancement upon (64)Cu decay to the daughter isotopes (64)Ni and (64)Zn. The dynamic switch from high radioactivity and low fluorescence to low radioactivity and high fluorescence is potentially useful for developing complementary multimodal imaging and detection platforms for chemical, environmental, and biomedical applications as well as for unraveling the mechanisms of metal-induced dynamic fluorescence changes.

  10. a New Strongly Deformed Proton-Emitter 117La

    Science.gov (United States)

    Soramel, F.; Guglielmetti, A.; Bonetti, R.; Poli, G. L.; Malerba, F.; Bianchi, E.; Stroe, L.; Müller, L.; Andrighetto, A.; Guo, J. Y.; Li, Z. C.; Maglione, E.; Scarlassara, F.; Signorini, C.; Liu, Z. H.; Ruan, M.; Ivascu, M.; Broude, C.; Ferreira, L. S.

    2001-11-01

    The decay by proton emission of the 117La nucleus has been studied via the 310 MeV 58Ni + 64Zn reaction. The nucleus has two levels that decay to the ground state of 116Ba with Ep = 783(6) keV (T1/2 = 20(5) ms) and Ep = 933(10) keV (T1/2 = 10(5) ms). Calculations done for a deformed proton emitter reproduce the experimental results confirming that 117La is well deformed (β2 ~ 0.3).

  11. Correlations between the fragmentation modes and light charged particles emission in heavy ion collisions

    CERN Document Server

    Zhang, Yingxun; Chen, Jixian; Wang, Ning; Zhao, Kai; Li, Zhuxia

    2015-01-01

    The correlations between the shape of rapidity distribution of the yield of light charged particles and the fragmentation modes in semi-peripheral collisions for $^{70}$Zn+$^{70}$Zn, $^{64}$Zn+$^{64}$Zn and $^{64}$Ni+$^{64}$Ni at the beam energy of 35MeV/nucleon are 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 $R_{yield}^{mid}$ compared with the multi-fragmentation break-up mode does. The reduced rapidity distribution for the normalized yields of p, d, t, $^3$He, $^4$He and $^6$He and the corresponding values of $R_{yield}^{mid}$ can be used to estimate the probability of multi-fragmentation break-up modes. By comparing to experimental data, our results illustrate that $\\ge$40\\% of the collisions events belong to the multi-fragmentation break-up mode for the reactions we studied.

  12. Experimental and theoretical investigation of isotope fractionation of zinc between aqua, chloro, and macrocyclic complexes.

    Science.gov (United States)

    Fujii, Toshiyuki; Moynier, Frédéric; Telouk, Philippe; Abe, Minori

    2010-02-25

    This work reports on the chemical isotope fractionation of Zn(II) by a solvent extraction method with the crown ether dicyclohexano-18-crown-6. The (m)Zn/(64)Zn ratios (m = 66, 67, and 68) were analyzed by multiple-collector inductively coupled plasma mass spectrometry. The relative deviations of the (66)Zn/(64)Zn ratios relative to the unprocessed material (delta(66)Zn) was determined to be -0.51 to -0.32 in the acidity region 1.0-6.0 mol dm(-3) (M) HCl. The acidity dependence of delta(m)Zn was explained by the isotope exchange reactions between Zn(II) species (Zn(2+), ZnCl(+), ZnCl(2), ZnCl(3)(-), and ZnCl(4)(2-)) and the mole fractions of them. The magnitude of delta(m)Zn due to the related Zn(II) species estimated by quantum chemical calculations was in agreement with delta(m)Zn experimentally obtained. Contribution of nuclear field shift to the isotope fractionation was estimated to be less than 10% of delta(m)Zn by quantum chemical calculations.

  13. Signature inversion in doubly odd {sup124}La.

    Energy Technology Data Exchange (ETDEWEB)

    Chantler, H. J.; Paul, E. S.; Boston, A. J.; Carpenter, M. P.; Charity, R.; Chiara, C. J.; Choy, P. T. W.; Davids, C. N.; Devlin, M.; Fletcher, A. M.; Fossan, D. B.; Jenkins, D. G.; Kelsall, N. S.; Koike, T.; LaFosse, D. R.; Nolan, P. J.; Sarantites, D. G.; Seweryniak, D.; Smith, J. F.; Starosta, K.; Wadsworth, R.; Wilson, A. N.; Physics; Univ. of Liverpool; Washington Univ.; State Univ. of New York, Stony Brook; Univ. of Manchester; Univ. of York

    2002-07-01

    High-spin states have been studied in neutron-deficient {sup 124}{sub 57}La{sub 67}, populated through the {sup 64}Zn({sup 64}Zn,3pn) reaction at 260 MeV. The Gammasphere {gamma}-ray spectrometer has been used in conjunction with the Microball charged-particle detector, the Neutron Shell, and the Argonne Fragment Mass Analyzer, in order to select evaporation residues of interest. The known band structures have been extended and new bands found. Most of the bands are linked together, allowing more consistent spin and parity assignments. Comparison of band properties to cranking calculations has allowed configuration assignments to be made and includes the first identification of the g{sub 9/2} proton-hole in an odd-odd lanthanum isotope. Two bands have been assigned a {pi}h{sub 11/2}{circle_times}{nu}h{sub 11/2} structure; the yrast one exhibits a signature inversion in its level energies below I=18.5{Dirac_h}, while the excited one exhibits a signature inversion above I=18.5{Dirac_h}.

  14. Search for double beta decay of zinc and tungsten with low background ZnWO{sub 4} crystal scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Belli, P. [Dipartimento di Fisica, Universita di Roma ' Tor Vergata' and INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy); Bernabei, R. [Dipartimento di Fisica, Universita di Roma ' Tor Vergata' and INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy)], E-mail: rita.bernabei@roma2.infn.it; Cappella, F. [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, I-00185 Rome (Italy); Cerulli, R. [INFN, Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ) (Italy); Danevich, F.A. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Grinyov, B.V. [Institute for Scintillation Materials, 61001 Kharkiv (Ukraine); Incicchitti, A. [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, I-00185 Rome (Italy); Kobychev, V.V.; Mokina, V.M.; Nagorny, S.S. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Nagornaya, L.L. [Institute for Scintillation Materials, 61001 Kharkiv (Ukraine); Nisi, S. [INFN, Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ) (Italy); Nozzoli, F. [Dipartimento di Fisica, Universita di Roma ' Tor Vergata' and INFN, Sezione di Roma Tor Vergata, I-00133 Rome (Italy); Poda, D.V. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine); Prosperi, D. [Dipartimento di Fisica, Universita di Roma ' La Sapienza' and INFN, Sezione di Roma, I-00185 Rome (Italy); Tretyak, V.I.; Yurchenko, S.S. [Institute for Nuclear Research, MSP 03680 Kyiv (Ukraine)

    2009-08-01

    Double beta processes in {sup 64}Zn, {sup 70}Zn, {sup 180}W, and {sup 186}W have been searched for with the help of large volume (0.1-0.7 kg) low background ZnWO{sub 4} crystal scintillators at the Gran Sasso National Laboratories of the INFN (Italy). The total measurement time exceeds ten thousand hours. New improved half-life limits on double electron capture and electron capture with positron emission in {sup 64}Zn have been set, in particular (all the limits are at 90% C.L.): T{sub 1/2}{sup 0{nu}}{sup 2{epsilon}}{>=}1.1x10{sup 20} yr, T{sub 1/2}{sup 2{nu}}{sup {epsilon}}{sup {beta}{sup +}}{>=}7.0x10{sup 20} yr, and T{sub 1/2}{sup 0{nu}}{sup {epsilon}}{sup {beta}{sup +}}{>=}4.3x10{sup 20} yr. In addition, new T{sub 1/2} bounds were set for different modes of 2{beta} processes in {sup 70}Zn, {sup 180}W, and {sup 186}W at the level of 10{sup 17}-10{sup 20} yr.

  15. Neutron activation of natural zinc samples at kT = 25 keV

    CERN Document Server

    Reifarth, R; Heil, M; Käppeler, F; Plag, R; Sonnabend, K; Uberseder, E

    2013-01-01

    The neutron-capture cross sections of 64Zn, 68Zn, and 70Zn have been measured with the activation technique in a quasistellar neutron spectrum corresponding to a thermal energy of kT = 25 keV. By a series of repeated irradiations with different experimental conditions, an uncertainty of 3% could be achieved for the 64Zn(n,g)65Zn cross section and for the partial cross section 68Zn(n,g)69Zn-m feeding the isomeric state in 69Zn. For the partial cross sections 70Zn(n,g)71Zn-m and 70Zn(n,g)71Zn-g, which had not been measured so far, uncertainties of only 16% and 6% could be reached because of limited counting statistics and decay intensities. Compared to previous measurements on 64,68Zn, the uncertainties could be significantly improved, while the 70Zn cross section was found to be two times smaller than existing model calculations. From these results Maxwellian average cross sections were determined between 5 and 100 keV. Additionally, the beta-decay half-life of 71Zn-m could be determined with significantly imp...

  16. New Production Routes for Medical Isotopes 64Cu and 67Cu Using Accelerator Neutrons

    Science.gov (United States)

    Kin, Tadahiro; Nagai, Yasuki; Iwamoto, Nobuyuki; Minato, Futoshi; Iwamoto, Osamu; Hatsukawa, Yuichi; Segawa, Mariko; Harada, Hideo; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke

    2013-03-01

    We have measured the activation cross sections producing 64Cu and 67Cu, promising medical radioisotopes for molecular imaging and radioimmunotherapy, by bombarding a natural zinc sample with 14 MeV neutrons. We estimated the production yields of 64Cu and 67Cu by fast neutrons from \\text{natC(d,n) with 40 MeV 5 mA deuterons. We used the present result together with the evaluated cross section of Zn isotopes. The calculated 64Cu yield is 1.8 TBq (175 g 64Zn) for 12 h of irradiation; the yields of 67Cu by 67Zn(n,p)67Cu and 68Zn(n,x)67Cu were 249 GBq (184 g 67Zn) and 287 GBq (186 g 68Zn) at the end of 2 days of irradiation, respectively. From the results, we proposed a new route to produce 67Cu with very little radionuclide impurity via the 68Zn(n,x)67Cu reaction, and showed the 64Zn(n,p)64Cu reaction to be a promising route to produce 64Cu. Both 67Cu and 64Cu are noted to be produced using fast neutrons.

  17. Studying dispersions of ferroelectric nanopowders in dioctyl phthalate as dielectric media for capacitive electronic components

    Science.gov (United States)

    Gorokhovskii, A. V.; Gorshkov, N. V.; Burmistrov, I. N.; Goffman, V. G.; Tret'yachenko, E. V.; Sevryugin, A. V.; Fedorov, F. S.; Kovyneva, N. N.

    2016-06-01

    The electrical properties of dispersions of a powdered ferroelectric nanocomposite based on ilmenite (FeTiO3) and hollandite (K1.46Ti7.2Fe0.8O16) in dioctyl phthalate have been studied by impedance spectroscopy techniques in a frequency range of 10-1-106 Hz. The influence of stabilizing additives of cationic and anionic surfactants and iron acetylacetonate on the permittivity, conductivity, and dielectric losses was determined for dispersions containing 40 mass % of the solid composite. The influence of composition on the mechanisms of relaxation processes in the system is discussed.

  18. Study of proton hole states in 1f/sub 7/2/ nuclei by the (p,2p) reaction at 46 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Bertrand, F.; Eisberg, R.; Ingham, D.; Makino, M.; Waddell, C.

    1970-03-01

    Proton hole states in the 1f/sub 7/2/ nuclei /sup 46/Ti, /sup 54/Fe, /sup 56/Fe, /sup 58/Ni, and /sup 60/Ni have been studied with the (p,2p) reaction with 46-MeV protons. The measured binding energies and angular correlations are consistent with the binding energies and orbital angular momentum assignments (1f/sub 7/2/, 2s/sub 1/2/, and 1d/sub 3/2/) obtained from proton pick-up reactions. 3 figures, 1 table.

  19. Nuclear Level Density and Gamma-Ray Strength Function of 43Sc

    CERN Document Server

    Bürger, A; Hilaire, S; Guttormsen, M; Harissopulos, S; Kmiecik, M; Konstantinopoulos, T; Krticka, M; Lagoyannis, A; Lönnroth, T; Mazurek, K; Norrby, M; Nyhus, H T; Perdikakis, G; Siem, S; Spyrou, A; Syed, N U H; 10.1103/PhysRevC.85.064328

    2012-01-01

    The nuclear level density and the gamma-ray strength function have been determined for 43Sc in the energy range up to 2 MeV below the neutron separation energy using the Oslo method with the 46Ti(p,alpha)43Sc reaction. A comparison to 45Sc shows that the level density of 43Sc is smaller by an approximately constant factor of two. This behaviour is well reproduced in a microscopical/combinatorial model calculation. The gamma-ray strength function is showing an increase at low gamma-ray energies, a feature which has been observed in several nuclei but which still awaits theoretical explanation.

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

    Energy Technology Data Exchange (ETDEWEB)

    Leinekugel-le-Cocq, A.Y.; Deniard, P.; Jobic, S.; Bart, F.; Evain, M.; Gautier, E

    2004-07-01

    Investigations on the Ba{sub 1}Cs{sub 0.28}Fe{sub 0.82}Al{sub 1.46}Ti{sub 5.72}O{sub 16} 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 {theta} =19.5 and 27 angle, {lambda} = 1.54059 A). The space group I4/m(0 0 {gamma}) 0 0 was determined thanks to the X-Ray of single crystal analysis on a simplified Ba{sub 1.16}Al{sub 2.32}Ti{sub 5.68}O{sub 16} material. The electron diffraction confirmed that this result could be transposed to our formulation Ba{sub 1}Cs{sub 0.28}Fe{sub 0.82}Al{sub 1.46}Ti{sub 5.72}O{sub 16}. 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)

  1. Neutron capture cross section of unstable 63Ni implications for stellar nucleosynthesis

    CERN Document Server

    Lederer, C; Altstadt, S; Andrzejewski, J; Audouin, L; Barbagallo, M; Becares, V; Becvar, F; Belloni, F; Berthoumieux, E; Billowes, J; Boccone, V; Bosnar, D; Brugger, M; Calviani, M; Calvino, F; Cano-Ott, D; Carrapico, C; Cerutti, F; Chiaveri, E; Chin, M; Colonna, N; Cortes, G; Cortes-Giraldo, M.A; Diakaki, M; Domingo-Pardo, C; Duran, I; Dressler, R; Dzysiuk, N; Eleftheriadis, C; Ferrari, A; Fraval, K; Ganesan, S; Garcia, A R; Giubrone, G; Gomez-Hornillos, M B; Goncalves, I F; Gonzalez-Romero, E; Griesmayer, E; Guerrero, C; Gunsing, F; Gurusamy, P; Jenkins, D G; Jericha, E; Kadi, Y; Kappeler, F; Karadimos, D; Kivel, N; Koehler, P; Kokkoris, M; Korschinek, G; Krticka, M; Kroll, J; Langer, C; Leeb, H; Leong, L S; Losito, R; Manousos, A; Marganiec, J; Martinez, T; Mastinu, P F; Mastromarco, M; Meaze, M; Mendoza, E; Mengoni, A; Milazzo, P M; Mingrone, F; Mirea, M; Mondelaers, W; Paradela, C; Pavlik, A; Perkowski, J; Pignatari, M; Plompen, A; Praena, J; Quesada, J M; Rauscher, T; Reifarth, R; Riego, A; Roman, F; Rubbia, C; Sarmento, R; Schillebeeckx, P; Schmidt, S; Schumann, D; Tagliente, G; Tain, J L; Tarrio, D; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Versaci, R; Vermeulen, M J; Vlachoudis, V; Vlastou, R; Wallner, A; Ware, T; Weigand, M; Weiss, C; Wright, T J; Zugec, P

    2013-01-01

    The $^{63}$Ni($n, \\gamma$) cross section has been measured for the first time at the neutron time-of-flight facility n\\_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian Averaged Cross Sections were calculated for thermal energies from kT = 5 keV to 100 keV with uncertainties around 20%. Stellar model calculations for a 25 M$_\\odot$ star show that the new data have a significant effect on the $s$-process production of $^{63}$Cu, $^{64}$Ni, and $^{64}$Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

  2. Reaction mechanisms in collisions induced by $^{8}$B beam close to the barrier

    CERN Multimedia

    The aim of the proposed experiment is to investigate 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 the $^{8}$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.

  3. First identification of excited states in 117Ba using the recoil-β -delayed proton tagging technique

    Science.gov (United States)

    Ding, B.; Liu, Z.; Seweryniak, D.; Woods, P. J.; Wang, H. L.; Yang, J.; Liu, H. L.; Davids, C. N.; Carpenter, M. P.; Davinson, T.; Janssens, R. V. F.; Page, R. D.; Robinson, A. P.; Shergur, J.; Sinha, S.; Zhu, S.; Tang, X. D.; Wang, J. G.; Huang, T. H.; Zhang, W. Q.; Sun, M. D.; Liu, X. Y.; Lu, H. Y.

    2017-02-01

    Excited states have been observed for the first time in the neutron-deficient nucleus 117Ba using the recoil-decay tagging technique following the heavy-ion fusion-evaporation reaction 64Zn(58Ni, 2p3n)117Ba. Prompt γ rays have been assigned to 117Ba through correlations with β -delayed protons following the decay of A =117 recoils. Through the analysis of the γ -γ coincidence relationships, a high-spin level scheme consisting of two bands has been established in 117Ba. Based on the systematics of the level spacings in the neighboring barium isotopes, the two bands are proposed to have ν h11 /2[532 ] 5 /2- and ν d5 /2[413 ] 5 /2+ configurations, respectively. The observed band-crossing properties are interpreted in the framework of cranked shell model.

  4. Atom probe microscopy of zinc isotopic enrichment in ZnO nanorods

    Directory of Open Access Journals (Sweden)

    C. N. Ironside

    2017-02-01

    Full Text Available We report on atomic probe microscopy (APM of isotopically enriched ZnO nanorods that measures the spatial distribution of zinc isotopes in sections of ZnO nanorods for natural abundance natZnO and 64Zn and 66Zn enriched ZnO nanorods. The results demonstrate that APM can accurately quantify isotopic abundances within these nanoscale structures. Therefore the atom probe microscope is a useful tool for characterizing Zn isotopic heterostructures in ZnO. Isotopic heterostructures have been proposed for controlling thermal conductivity and also, combined with neutron transmutation doping, they could be key to a novel technology for producing p-n junctions in ZnO thin films and nanorods.

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

    CERN Document Server

    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.

  6. ZnWO{sub 4} crystals as detectors for 2{beta} decay and dark matter experiments

    Energy Technology Data Exchange (ETDEWEB)

    Danevich, F.A. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine)]. E-mail: danevich@kinr.kiev.ua; Kobychev, V.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Nagorny, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Poda, D.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Tretyak, V.I. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Yurchenko, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Zdesenko, Yu.G. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine)

    2005-06-01

    Energy resolution, {alpha}/{beta} ratio, and the pulse shape discrimination ability of the ZnWO{sub 4} crystal scintillators were studied. The radioactive contamination of a ZnWO{sub 4} crystal was investigated in the Solotvina Underground Laboratory. Possibilities to apply ZnWO{sub 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 -bar {beta}{sup +} decay of {sup 64}Zn as: T{sub 1/2}{sup 2{nu}}>=8.9x10{sup 18} years and T{sub 1/2}{sup 0{nu}}>=3.6x10{sup 18} years, both at 68% CL.

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

    CERN Document Server

    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.

  8. Formation of a low-crystalline Zn-silicate in a stream in SW Sardinia, Italy

    Science.gov (United States)

    Wanty, Richard B.; De Giudici, G.; Onnis, P.; Rutherford, D.; Kimball, B.A.; Podda, F.; Cidu, R.; Lattanzi, P.; Medas, D.

    2013-01-01

    n southwestern Sardinia, Italy, the Rio Naracauli drains a catchment that includes several abandoned mines. The drainage from the mines and associated waste rocks has led to extreme concentrations of dissolved Zn, but because of the near-neutral pH, concentrations of other metals remain low. In the reach from approximately 2300 to 3000 m downstream from the headwaters area, an amorphous Zn-silicate precipitates from the water. In this reach, concentrations of both Zn and silica remain nearly constant, but the loads (measured in mass/time) of both increase, suggesting that new Zn and silica are supplied to the stream, likely from emerging groundwater. Zinc isotope signatures of the solid are heavier than the dissolved Zn by about 0.5 permil in 66/64Zn, suggesting that an extracellular biologically mediated adsorption process may be involved in the formation of the Zn-silicate.

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

    CERN Document Server

    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.

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

    CERN Document Server

    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.

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

    Science.gov (United States)

    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.

  12. First observation of proton emission from 117La

    Science.gov (United States)

    Soramel, F.; Guglielmetti, A.; Stroe, L.; Müller, L.; Bonetti, R.; Malerba, F.; Poli, G. L.; Boiano, C.; Andrighetto, A.; Li, Z. C.; Scarlassara, F.; Signorini, C.; Bello, A. Dal; Isocrate, R.; Liu, Z. H.; Ruan, M.; Ivascu, M.; Bednarczyk, P.; Broude, C.

    2000-05-01

    We report the first measurement, at the XTU Tandem+LINAC accelerator of the Laboratori Nazionali di Legnaro, of the decay of the very neutron deficient nucleus 117La using a 310 MeV 58Ni beam on a 64Zn target; the 117La nucleus was populated via the (p, 4n) evaporation channel. The Recoil Mass Spectrometer (RMS) was used to select M/q=117/30 recoils that were implanted in a (40×40) mm2 Double Sided Silicon Strip Detector (DSSD) detector. The analysis has revealed that 117La decays to 116Ba via proton emission with Ep=(783±6)keV and T1/2=(20±5) ms. From this result deformation parameters of β2=0.3 and β4=0.1 have been deduced for the 117La ground state which was assigned to Jπ=3/2+.

  13. Nuclear level densities of 64,66Zn from neutron evaporation

    Science.gov (United States)

    Ramirez, A. P. D.; Voinov, A. V.; Grimes, S. M.; Schiller, A.; Brune, C. R.; Massey, T. N.; Salas-Bacci, A.

    2013-12-01

    Double differential cross sections of neutrons from d+63,65Cu reactions have been measured at deuteron energies of 6 and 7.5 MeV. The cross sections measured at backward angles have been compared to theoretical calculations in the framework of the statistical Hauser-Feshbach model. Three different level density models were tested: the Fermi-gas model, the Gilbert-Cameron model, and the microscopic approach through the Hartree-Fock-Bogoliubov method (HFBM). The calculations using the Gilbert-Cameron model are in best agreement with our experimental data. Level densities of the residual nuclei 64Zn and 66Zn have been obtained from statistical neutron evaporation spectra. The angle-integrated cross sections have been analyzed with the exciton model of nuclear reaction.

  14. Mediating conducting polymer growth within hydrogels by controlling nucleation

    Directory of Open Access Journals (Sweden)

    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.

  15. Laboratory tests of low density astrophysical nuclear equations of state.

    Science.gov (United States)

    Qin, L; Hagel, K; Wada, R; Natowitz, J B; Shlomo, S; Bonasera, A; Röpke, G; Typel, S; Chen, Z; Huang, M; Wang, J; Zheng, H; Kowalski, S; Barbui, M; Rodrigues, M R D; Schmidt, K; Fabris, D; Lunardon, M; Moretto, S; Nebbia, G; Pesente, S; Rizzi, V; Viesti, G; Cinausero, M; Prete, G; Keutgen, T; El Masri, Y; Majka, Z; Ma, Y G

    2012-04-27

    Clustering in low density nuclear matter has been investigated using the NIMROD multidetector at Texas A&M University. Thermal coalescence modes were employed to extract densities, ρ, and temperatures, T, for evolving systems formed in collisions of 47A MeV (40)Ar+(112)Sn, (124)Sn and (64)Zn+(112)Sn, (124)Sn. The yields of d, t, (3)He, and (4)He have been determined at ρ=0.002 to 0.03 nucleons/fm(3) and T=5 to 11 MeV. The experimentally derived equilibrium constants for α particle production are compared with those predicted by a number of astrophysical equations of state. The data provide important new constraints on the model calculations.

  16. Fe and Cu stable isotopes in archeological human bones and their relationship to sex.

    Science.gov (United States)

    Jaouen, Klervia; Balter, Vincent; Herrscher, Estelle; Lamboux, Aline; Telouk, Philippe; Albarède, Francis

    2012-07-01

    Accurate sex assignment of ancient human remains usually relies on the availability of coxal bones or well-preserved DNA. Iron (Fe) and copper (Cu) stable isotope compositions ((56)Fe/(54)Fe and (65)Cu/(63)Cu, respectively) were recently measured in modern human blood, and an unexpected result was the discovery of a (56)Fe-depletion and a (65)Cu-enrichment in men's blood compared to women's blood. Bones, being pervasively irrigated by blood, are expected to retain the (56)Fe/(54)Fe and (65)Cu/(63)Cu signature of blood, which in turn is useful for determining the sex of ancient bones. Here, we report the (56)Fe/(54)Fe, (65)Cu/(63)Cu, and (66)Zn/(64)Zn ratios from a suite of well-preserved phalanxes (n = 43) belonging to individuals buried in the 17th and 18th centuries at the necropolis of Saint-Laurent de Grenoble, France, and for which the sex was independently estimated from pelvic bone morphology. The metals were purified from the bone matrix by liquid chromatography on ion exchange resin and the isotope compositions were measured by multiple-collector inductively coupled plasma mass spectrometry. The results show that, as expected from literature data on blood, male bone iron is depleted in (56)Fe and enriched in (65)Cu relative to female. No sex difference is found in the (66)Zn/(64)Zn ratios of bone. The concentration and isotopic data show no evidence of soil contamination. Four samples of five (77%) can be assigned their correct sex, a result comparable to sex assignment using Fe and Cu isotopes in blood (81%). Isotopic analysis of metals may therefore represent a valid method of sex assignment applicable to incomplete human remains.

  17. Effects of annealing on mechanical behavior of Zr–Ti–Ni thin film metallic glasses

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chu-Shuan [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Yiu, Pakman [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Department of Physics and Materials Science, City University of Hong Kong, Kowloon, Hong Kong (China); Li, Chia-Lin; Chu, Jinn P. [Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Shek, Chan-Hung [Department of Physics and Materials Science, City University of Hong Kong, Kowloon, Hong Kong (China); Hsueh, Chun-Hway, E-mail: hsuehc@ntu.edu.tw [Department of Materials Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2014-07-01

    Zr{sub 46}Ti{sub 26}Ni{sub 28} thin film metallic glass was fabricated by radio frequency magnetron single target sputtering on Si and stainless steel substrates. The as-deposited film was found to be fully amorphous with high glass transition and crystallization temperatures of 466 °C and 502 °C, respectively. Its hardness progressively increased from 6.2 GPa to as high as 11.1 GPa when subjected to annealing near the glass-transition temperature at 450 °C. It was also of good adhesive strength and scratch resistance after the annealing treatment at 400 °C. Transmission electron microscopy results revealed annealing-induced nanocrystals that accounted for such superior mechanical properties. With the above unique properties, Zr–Ti–Ni thin film metallic glass has the potential for the fabrication of high strength micro parts and protective coating.

  18. Synthesis, characterization and investigation of electrochemical and spectroelectrochemical properties of non-peripherally tetra-5-methyl-1,3,4-thiadiazole substituted copper(II) iron(II) and oxo-titanium (IV) phthalocyanines

    Science.gov (United States)

    Demirbaş, Ümit; Akyüz, Duygu; Akçay, Hakkı Türker; Barut, Burak; Koca, Atıf; Kantekin, Halit

    2017-09-01

    In this study novel substituted phthalonitrile (3) and non-peripherally tetra 5-Methyl-1,3,4-thiadiazole substituted copper(II) (4), iron(II) (5) and oxo-titanium (IV) (6) phthalocyanines were synthesized. These novel compounds were fully characterized by FT-IR, 1H NMR, UV-vis and MALDI-TOF mass spectroscopic techniques. Voltammetric and in situ spectroelectrochemical measurements were performed for metallo-phthalocyanines (4-6). TiIVOPc and FeIIPc showed metal-based and ligand-based electron transfer reactions while CuIIPc shows only ligand-based electron transfer reaction. Voltammetric measurements indicated that the complexes have reversible, diffusion controlled and one-electron redox reactions. The assignments of the redox processes and color of the electrogenerated species of the complexes were determined with in-situ spectroelectrochemical and electrocolorimetric measurements. These measurements showed that the complexes can be used as the electrochromic materials for various display technologies.

  19. Measurement of (43)Sc and (44)Sc production cross-section with an 18MeV medical PET cyclotron.

    Science.gov (United States)

    Carzaniga, Tommaso Stefano; Auger, Martin; Braccini, Saverio; Bunka, Maruta; Ereditato, Antonio; Nesteruk, Konrad Pawel; Scampoli, Paola; Türler, Andreas; van der Meulen, Nicholas

    2017-11-01

    (43)Sc and (44)Sc are positron emitter radionuclides that, in conjunction with the β(-) emitter (47)Sc, represent one of the most promising possibilities for theranostics in nuclear medicine. Their availability in suitable quantity and quality for medical applications is an open issue and their production with medical cyclotrons represents a scientific and technological challenge. For this purpose, an accurate knowledge of the production cross sections is mandatory. In this paper, we report on the cross section measurement of the reactions (43)Ca(p,n)(43)Sc, (44)Ca(p,2n) (43)Sc, (46)Ti(p,α)(43)Sc, and (44)Ca(p,n)(44)Sc at the Bern University Hospital cyclotron. A study of the production yield and purity performed by using commercially available enriched target materials is also presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  1. Marker experiments to determine diffusing species and diffusion path in medical Nitinol alloys

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, J. [Leibniz-Institut fuer Oberflaechenmodifizierung, Permoserstr. 15, 04318 Leipzig (Germany); Universitaet Leipzig, Translational Centre for Regenerative Medicine (TRM-Leipzig), 04103 Leipzig (Germany); Lindner, J.K.N. [Institut fuer Physik, Universitaet Augsburg, 86135 Augsburg (Germany); Maendl, S. [Leibniz-Institut fuer Oberflaechenmodifizierung, Permoserstr. 15, 04318 Leipzig (Germany)], E-mail: stephan.maendl@iom-leipzig.de

    2008-12-15

    The out-diffusion of toxic Ni ions from NiTi (Nitinol), often used for biomedical applications, can be strongly reduced using oxygen plasma immersion ion implantation (PIII). Non-radioactive isotope markers, {sup 60}Ni and {sup 46}Ti, were implanted at 180 keV into NiTi prior to the oxygen implantation with fluences between 0.4 x 10{sup 16} and 4 x 10{sup 16} at./cm{sup 2}. Implanting oxygen ions by PIII in the temperature range of 400-550 deg. C leads to a surface oxide layer consisting of pure TiO{sub 2}. The results prove that Ni cations are the mobile species, while Ti is immobile during the oxygen insertion.

  2. Tracing Cd, Zn and Pb pollution sources in bivalves using isotopes

    Science.gov (United States)

    Shiel, A. E.; Weis, D. A.; Orians, K. J.

    2010-12-01

    In a multi-tracer study, Cd, Zn and Pb isotopes (MC-ICP-MS) and elemental concentrations (HR-ICP-MS) are evaluated as tools to distinguish between natural and anthropogenic sources of these metals in bivalves from western Canada (British Columbia), the eastern USA, Hawaii and France. High Cd concentrations found in BC oysters have elicited economic and health concerns. The source of these high Cd levels is unknown but thought to be largely natural. High Cd levels in BC oysters are largely attributed to the natural upwelling of Cd-rich intermediate waters in the North Pacific as the δ114/110Cd (-0.69 to -0.09‰) and δ66/64Zn (0.28 to 0.36‰) values of BC oysters fall within the range reported for North Pacific seawater. Different contributions from anthropogenic sources account for the variability of Cd isotopic compositions of BC oysters; the lightest of these oysters are from the BC mainland. These oysters also have Pb isotopic compositions that reflect primarily anthropogenic sources (e.g., leaded and unleaded automotive gasoline and smelting of Pb ores, potentially historical). On the contrary, USA East Coast bivalves exhibit relatively light Cd isotopic compositions (δ114/110Cd = -1.20 to -0.54‰; lighter than reported for North Atlantic seawater) due to the high prevalence of industry on this coast. The Pb isotopic compositions of these bivalves indicate contributions from the combustion of coal. The large variability of environmental health among coastal areas in France is reflected in the broad range of Cd isotopic compositions exhibited by French bivalves (δ114/110Cd = -1.08 to -0.20‰). Oysters and mussels from the Marennes-Oléron basin and Gironde estuary have the lightest Cd isotopic compositions of the French oysters consistent with significant historical Cd emissions from the now-closed proximal Zn smelter. In these bivalves, significant declines in the Cd levels between 1984/7 and 2004/5 are not accompanied by a significant shift in the Cd

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

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  7. Heterogeneous distribution of Zn stable isotopes in mice and applications to medical sciences

    Science.gov (United States)

    Moynier, F.; Fujii, T.; Shaw, A.; Le Borgne, M.

    2013-12-01

    Zinc is required for the function of more than 300 enzymes involved in many metabolic pathways, and is a vital micronutrient for living organisms. To investigate if Zn isotopes could be used to better understand metal homeostasis, as well as a biomarker for diseases, we assessed the distribution of natural Zn isotopes in various mouse tissues. We found that, with respect to Zn isotopes, most mouse organs are isotopically distinct and that the total range of variation within one mouse encompasses the variations observed in the Earth's crust. Therefore, biological activity must have a major impact on the distribution of Zn isotopes in inorganic materials. The most striking aspect of the data is that red blood cells and bones are enriched by ~0.5 per mil in 66Zn relative to 64Zn when compared to serum, and up to ~1 per mil when compared to the brain and liver. This fractionation is well explained by the equilibrium distribution of isotopes between different bonding environments of Zn in different organs. Differences in gender and genetic background did not appear to affect the isotopic distribution of Zn. Together, these results suggest that potential use of Zn isotopes as a tracer for dietary Zn, and for detecting disturbances in Zn metabolism due to pathological conditions.

  8. Effects of thermal treatment and depth profiling analysis of solution processed bulk-heterojunction organic photovoltaic cells.

    Science.gov (United States)

    Mbule, Pontsho S; Swart, Hendrik C; Ntwaeaborwa, Odireleng M

    2014-12-15

    We report the use of solution processed zinc oxide (ZnO) nanoparticles as a buffer layer inserted between the top metal electrode and the photo-active layer in bulk-heterojunction (BHJ) organic solar cell (OSC) devices. The photovoltaic properties were compared for devices annealed before (Device A) or after (Device B) the deposition of the Al top electrode. The post-annealing treatment was shown to improve the power conversion efficiency up to 2.93% and the fill factor (FF) up to 63% under AM1.5 (100mW/cm(2)) illumination. We performed the depth profile/interface analysis and elemental mapping using the time-of-flight secondary ion mass spectrometry (TOF-SIMS). Signals arising from (27)Al, (16)O, (12)C, (32)S, (64)Zn, (28)Si, (120)Sn and (115)In give an indication of successive deposition of Al, ZnO, P3HT:PCBM and PEDOT:PSS layers on ITO coated glass substrates. Furthermore, we discuss the surface imaging and visualize the chemical information on the surface of the devices.

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

    Science.gov (United States)

    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.).

  10. Influence of PbO and TiO2 additives on the microstructure development and magnetic properties of Ni–Zn soft ferrites

    Directory of Open Access Journals (Sweden)

    O. Mirzaee

    2014-07-01

    Full Text Available This paper focuses on the effect of PbO and TiO2 on the magnetic properties and microstructural development of Fe2Ni0.64Zn0.36O4 soft ferrite. Ferrite was added to these oxides, ranging from 0 to 3.2 wt% in steps of 0.4 wt%. The results showed that with increasing the amount of PbO up to a certain percentage, relative density, grain size and magnetic permeability increase and then decrease. This additive caused to increase DC-resistivity, power loss and decrease in magnetic permeability and saturation magnetization. TiO2 revealed no considerable effect on the grain growth and densification. In contrast this additive due to the doping of the high valent Ti4+ ions to the lattice affects the magnetic and electrical properties noticeably. TiO2 improved the loss properties (up to 1.2 wt% and magnetic permeability (up to 2.0 wt% but reduced the saturation magnetization, and DC-resistivity of ferrite.

  11. Experimental research of double beta decay of atomic nuclei

    CERN Document Server

    Danevich, F A

    2011-01-01

    Results of several double beta decay experiments, performed with the help of low background crystal scintillators, are presented. In particular, the half-life value of the two-neutrino double beta decay of 116-Cd has been measured as 2.9 10^{19} yr, and the new half-life limit on the neutrinoless double beta decay of 116-Cd has been established as >1.7 10^{23} yr at 90%, which corresponds to a restriction on the neutrino mass <1.7 eV. New half-life bounds on the level of 10^{17}-10^{21} yr were set for double beta processes in 64-Zn, 70-Zn, 106-Cd, 108-Cd, 114-Cd, 136-Ce, 138-Ce, 142-Ce, 160-Gd, 180-W, and 186-W by using low-background CdWO4, GSO, and ZnWO4 crystal scintillators. The claim of discovery of the neutrinoless double beta decay of 76-Ge [Mod. Phys. Lett. A 16 (2001) 2409] was analyzed. The demands of the future high sensitivity double beta decay experiments, aiming to observe the neutrinoless double beta decay or to advance restrictions on the neutrino mass to < 0.01 eV, were considered. Req...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  13. Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of AlZn

    Science.gov (United States)

    Behm, Jane M.; Blume, Thorsten; Morse, Michael D.

    1994-10-01

    Resonant two-photon ionization spectroscopy has been employed to investigate diatomic AlZn produced by laser vaporization of a 1:2 Al:Zn alloy target disk in a supersonic expansion of helium. Several discrete transitions are reported in the energy range from 18 400 to 19 100 cm-1. Most of these are assigned as members of the B 2Π←X 2Π system, although an isolated band has been observed and assigned as the 2-0 band of the A Ω'=0.5←X 2Π1/2 system. A pair of strongly mixed levels are identified as resulting from a homogeneous spin-orbit perturbation between the A Ω=0.5, v'=3 and the B 2Π1/2, v'=1 levels, and the perturbation matrix element has been deduced to be 8.11 cm-1 for 27Al64Zn, 8.23 cm-1 for 27Al66Zn. The ground state has been unambiguously identified as a 2Πr state with a bond length of 2.6957±0.0004 Å. Comparisons to the results of the preceding article on the spectroscopy of AlCa are also provided, along with a discussion of the chemical bonding in AlZn in relation to AlCa, AlAr, and AlKr.

  14. Ab initio calculation of the Zn isotope effect in phosphates, citrates, and malates and applications to plants and soil.

    Directory of Open Access Journals (Sweden)

    Toshiyuki Fujii

    Full Text Available Stable Zn isotopes are fractionated in roots and leaves of plants. Analyses demonstrate that the heavy Zn isotopes are enriched in the root system of plants with respect to shoots and leaves as well as the host soil, but the fractionation mechanisms remain unclear. Here we show that the origin of this isotope fractionation is due to a chemical isotope effect upon complexation by Zn malates and citrates in the aerial parts and by phosphates in the roots. We calculated the Zn isotope effect in aqueous citrates, malates, and phosphates by ab initio methods. For pH<5, the Zn isotopic compositions of the various parts of the plants are expected to be similar to those of groundwater. In the neutral to alkaline region, the calculations correctly predict that (66Zn is enriched over (64Zn in roots, which concentrate phosphates, with respect to leaves, which concentrate malates and citrates, by about one permil. It is proposed that Zn isotope fractionation represents a useful tracer of Zn availability and mobility in soils.

  15. First Observation of Proton Emission from {sup 117}La

    Energy Technology Data Exchange (ETDEWEB)

    Soramel, F.; Guglielmetti, A.; Stroe, L.; Muller, L.; Bonetti, R.; Malerba, F.; Poli, G.L.; Boiano, C.; Andrighetto, A.; Li, Z.C.; Scarlassara, F.; Signorini, C.; Dal Bello, A.; Isocrate, R.; Liu, Z.H.; Ruan, M.; Ivascu, M.; Bednarczyk, P.; Broude, C.

    2000-12-31

    We report the first measurement, at the XTU Tandem + LINAC accelerator of the Laboratori Nazionali di Legnaro, of the decay of the very neutron deficient nucleus {sup 117}La using a 310 MeV {sup 58}Ni beam on a {sup 64}Zn target; the {sup 117}La nucleus was populated via the (p,4n) evaporation channel. The Recoil Mass Spectrometer (RMS) was used to select M/q = 117/30 recoils that were implanted in a (40x40) mm{sup 2} Double Sided Silicon Strip Detector (DSSD) detector. The analysis has revealed that {sup 117}La decays to {sup 116}Ba via proton emission with E{sub p} = (783{+-}6)keV and T{sub 1/2} = (20{+-}5) ms. From this result deformation parameters of {beta}{sub 2} = 0.3 and {beta}{sub 4} = 0.1 have been deduced for the {sup 117}La ground state which was assigned to J{sup {pi}} = 3/2{sup +}.

  16. Evidence for a large radius of the 11Be projectile

    Science.gov (United States)

    So, W. Y.; Choi, K. S.; Cheoun, Myung-Ki; Kim, K. S.

    2016-05-01

    We investigate ratios of the elastic scattering cross section to Rutherford cross section, PE, and angular distributions of breakup cross section by using an optical model which exploits various long-range dynamic polarization potentials as well as short-range nuclear bare potentials for the 11Be projectile. From these simultaneous analyses, we extract a large radius of a halo projectile from the experimental data for PE and the angular distribution of the breakup cross section of the 11Be + 64Zn and 11 + 120Sn systems. It results from the fact that a large radius for the long-range nuclear potential is more reasonable for properly explaining these data simultaneously. The extracted reduced interaction radius turns out to be r0=3.18 ˜3.61 fm for 11Be nucleus, which is larger than the conventional value of r0=1.1 ˜1.5 fm used in the standard radius form R =r0A1 /3 . Furthermore, the larger radius as well as the normalization constant N is shown to be important for understanding Coulomb dipole strength distribution.

  17. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    Directory of Open Access Journals (Sweden)

    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.

  19. In Situ Ti Isotopic Measurements by Laser Ablation MC-ICP-MS

    Directory of Open Access Journals (Sweden)

    Hsin-Wei Chen

    2009-01-01

    Full Text Available We have been developing Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS technique to measure titanium isotopic composition in situ. A principal aim of this work is to search for isotopic heterogeneities larger than the few epsilons (e, in parts in 10^4 of the solar system. Our analytical precision of the ratios of 46Ti, 48Ti, and 50Ti to 49Ti after exponential-law mass discrimination correction normalizing 47Ti/49Ti to 1.33375 were about 2.5 £` (2£m. Mixture solutions were prepared by adding the expected level of Ca, Cr, Mg, and Alto the Ti solutions to demonstrate that our interference correction is effective. We then applied our technique with 213 nm Nd-YAG laser ablation to five Ti-rich terrestrial solids, and all of them also showed titanium isotopic composition that was consistent with one an other and agreed with that for the solution standard. It appears that the in situ laser technique did not significantly in crease the long-term reproducibility be yond the 2.5 established using the solution method. This is an order of magnitude better than the typical precision of a few permil for secondary ion mass spectrometry (SIMS. The combination of the ability to perform in situ analysis on 30 mm spots with e level precision is a niche for LA-MC-ICP-MS. We also ablated two lines on a fassaite grain from a large well studied CAI Egg-6 of the Allende meteorite. After the mass discrimination was corrected by normalizing 47Ti/49Ti, the 46Ti and 48Ti are nor mal within about 2 £ while 50Ti/49Ti shows a 9 £ excess. These data are in excellent agreement with thermalion ization mass spectrometry (TIMS results. Comparing our ICP-MS results against the results from TIMS studies, we found that our normal titanium isotopic ratios were closest to the less precise data of Heydegger et al. (1979 who measured Ti+. We support the proposal to IUPAC to change the accepted Ti abundance to that measured by ICP-MS and TIMS

  20. 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

    Energy Technology Data Exchange (ETDEWEB)

    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)

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

    Indian Academy of Sciences (India)

    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.

  2. Mass measurements and superallowed beta decay

    CERN Document Server

    Hardy, J C; Towner, I S

    2005-01-01

    A recent Penning-trap measurement of the masses of 46V and 46Ti leads to a Qec value that disagrees significantly with the previously accepted value, and destroys overall consistency among the nine most precisely characterized T=1 superallowed beta emitters. This raises the possibility of a systematic discrepancy between Penning-trap measurements and the reaction-based measurements upon which the Qec values depended in the past. We carefully re-analyze (n,gamma) and (p,gamma) reaction measurements in the 24 \\leq A \\leq 28 mass region, and compare the results to very precise Penning-trap measurements of the stable nuclei 24Mg, 26Mg and 28Si. We thus determine upper limits to possible systematic effects in the reaction results, and go on to establish limits for the mass of radioactive 26Al, to which future on-line Penning-trap measurements can be compared. We stress the urgency of identifying or ruling-out possible systematic effects.

  3. Primary gamma-ray spectra in 44Ti of astrophysical interest

    CERN Document Server

    Larsen, A C; Bürger, A; Guttormsen, M; Görgen, A; Harrisopulos, S; Kmiecik, M; Konstantinopoulos, T; Lagoyannis, A; Lönnroth, T; Mazurek, K; Norrby, M; Nyhus, H T; Perdikakis, G; Schiller, A; Siem, S; Spyrou, A; Syed, N U H; Toft, H K; Tveten, G M; Voinov, A; 10.1103/PhysRevC.85.014320

    2012-01-01

    Primary gamma-ray spectra for a wide excitation-energy range have been extracted for 44Ti from particle-gamma coincidence data of the 46Ti(p,t gamma)44Ti reaction. These spectra reveal information on the gamma-decay pattern of the nucleus, and may be used to extract the level density and radiative strength function applying the Oslo method. Models of the level density and radiative strength function are used as input for cross-section calculations of the 40Ca(alpha,gamma)44Ti reaction. Acceptable models should reproduce data on the 40Ca(alpha,gamma)44Ti reaction cross section as well as the measured primary gamma-ray spectra. This is only achieved when a coherent normalization of the slope of the level density and radiative strength function is performed. Thus, the overall shape of the experimental primary gamma-ray spectra puts a constraint on the input models for the rate calculations.

  4. Insensitivity of the Yrast Spectra of Even-Even Nuclei to the T=0 two-body interaction matrix elements

    CERN Document Server

    Robinson, S J Q; Robinson, Shadow J.Q.; Zamick, Larry

    2002-01-01

    Calculations of the spectra of various even-even nuclei in the fp shell ($^{44}$Ti, $^{46}$Ti, $^{48}$Cr, and $^{50}$Cr) are performed with two sets of two-body interaction matrix elements. The first set consists of the matrix elements of the FPD6 interaction. The second set have the same T=1 two-body matrix elements as the FPD6 interaction, but all the T=0 two-body matrix elements are set equal to zero. Despite the drastic differences between the two interactions, the spectra they yield are very similar and indeed it is difficult to say which set gives a better fit to experiment. That the results for the yrast spectra are insensitive to the presence or absence of T=0 two-body matrix elements is surprising because the only bound two nucleon system has T=0, namely the deuteron. Also there is the general folklore that T=0 matrix elements are responsible for nuclear collectivity. Electric quadrupole transition rates are also examined. It is found that the reintroduction of T=0 matrix elements leads to an enhance...

  5. Mixed ZnO-TiO2 Suspended Solution as an Efficient Photocatalyst for Decolonization of a Textile Dye from Waste Water

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Mooji

    2015-03-01

    Full Text Available Introduction: Textile industries produce large volume of colored dye effluents which are toxic and removal of dyes from wastewater is a significant environmental issue. Advanced oxidation process (AOPs is alternative method for the complete degradation many organic pollutants. ZnO and TiO2 are important photocatalysts with high catalytic activity that have attracted much research attention. Material and Methods: Mixed ZnO/TiO2 was prepared with mixing of ZnO and TiO2 (20, 40, 60, 80 % (w/w. 20 mL of dye solution (80 mgL-1 for DB71 containing the appropriate quantity of photocatalyst was magnetically stirred under UV irradiation. Photocatalytic study was carried out to evaluate the effect of UV (400 W, ZnO/TiO2 weight percent (20, 40, 60, 80 % (w/w, pH (2.3 – 9.2, irradiation time of (10 – 70 min, initial dye concentration of (10, 40, 80 mg/L and ZnO/TiO2 dosage of (0.2 – 1.6 g/L on removal of dye. Dye concentration was monitored spectrophotometrically by measuring the dye absorbance at 285 nm. Results: In comparison with TiO2 or ZnO as photocatalyst, mixed photocatalyst (ZnO/TiO2 is more efficient catalyst for degradation of dye under UV irradiation Results show that approximately 90 % of Direct Blue 71 has been eliminated after 70 minutes and optimized condition ((pH = 6.4, ZnO/TiO2 (50% w/w, 1.25 g/L. Experiments showed, the noticeable decolorization of dye solution can be done without any oxidation agent with mixed ZnO/TiO2 photocatalyst.

  6. Chemical and structural composition of Atlantic Canadian moose (Alces alces) incisors with patterns of high breakage.

    Science.gov (United States)

    MacKenzie, Cynthia S Kendall; Clough, Michael J; Broders, Hugh G; Tubrett, Mike

    2011-11-15

    Analysis of mammalian teeth can provide information regarding local environmental conditions. For example, a high incidence of breakage and wear within a population may indicate poor food quality. Individuals consuming a diet causing high mechanical stress on their teeth, and/or lacking the appropriate minerals for proper development, could experience degradation of tooth condition. Previously, we documented a high rate of incisor tooth breakage, with age, in two genetically distinct moose populations in Atlantic Canada. In this study, multi-element (11B, 63Cu, 64Zn, 75As, 85Rb, 88Sr, 111Cd, 118Sn, 137Ba, 208Pb, 232Th, and 238U) analyses using laser ablation ICP-MS were performed on moose incisors from multiple North American regions. The purpose was to determine whether the elemental composition of moose incisors varies among regions, and whether that variation is related to tooth degradation among Atlantic Canadian populations. A principal components analysis revealed that nearly 50% of the elemental variation in the inner enamel matrix of moose teeth was explained by three groupings of elements. The element groupings revealed differences among geographic regions, but did not explain the variation between incisors that were broken and those that were not. Regression models indicate that the elemental group which includes Cu, Pb, and Zn is related to decreases in incisal integrity. It is likely that other environmental factors contribute to the occurrence of increased incisor breakage in affected populations. The relationship between food resource quantity and quality, as a function of moose density, is hypothesized to explain loss of tooth integrity.

  7. Fast neutron activation dosimetry with TLDS

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Validation of minor actinides fission neutron cross-sections

    Directory of Open Access Journals (Sweden)

    Pešić Milan P.

    2015-01-01

    Full Text Available Verification of neutron fission cross-sections of minor actinides from some recently available evaluated nuclear data libraries was carried out by comparison of the reaction rates calculated by the MCNP6.1 computer code to the experimental values. The experimental samples, containing thin layers of 235U, 237Np, 238,239,240,241Pu, 242mAm, 243Cm, 245Cm, and 247Cm, deposited on metal support and foils of 235U (pseudo-alloy 27Al + 235U, 238U, natIn, 64Zn, 27Al, and multi-component sample alloy 27Al + 55Mn + natCu + natLu + 197Au, were irradiated in the channels of the tank containing fluorine salts 0.52NaF + 0.48ZrF4, labelled as the Micromodel Salt Blanket, inserted in the lattice centre of the MAKET heavy water critical assembly at the Institute for Theoretical and Experimental Physics, Moscow. This paper is a continuation of earlier initiated scientific-research activities carried out for validation of the evaluated fission cross-sections of actinides that were supposed to be used for the quality examination of the fuel design of the accelerator driven systems or fast reactors, and consequently, determination of transmutation rates of actinides, and therefore, determination of operation parameters of these reactor facilities. These scientific-research activities were carried out within a frame of scientific projects supported by the International Science and Technology Center and the International Atomic Energy Agency co-ordinated research activities, from 1999 to 2010. Obtained results confirm that further research is needed in evaluations in order to establish better neutron cross-section data for the minor actinides and selected nuclides which could be used in the accelerator driven systems or fast reactors.

  10. REACTION RATES OF {sup 64}Ge(p,γ){sup 65}As AND {sup 65}As(p,γ){sup 66}Se AND THE EXTENT OF NUCLEOSYNTHESIS IN TYPE I X-RAY BURSTS

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Y. H.; He, J. J.; Wang, M.; Zhang, Y. H.; Zhou, X. H.; Xu, H. S. [Key Laboratory of High Precision Nuclear Spectroscopy, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Parikh, A. [Departament de Física i Enginyeria Nuclear, EUETIB, Universitat Politècnica de Catalunya, Barcelona E-08036 (Spain); Schatz, H.; Brown, B. A. [Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824-1321 (United States); Guo, B., E-mail: jianjunhe@impcas.ac.cn, E-mail: anuj.r.parikh@upc.edu, E-mail: schatz@nscl.msu.edu [China Institute of Atomic Energy, P.O. Box 275(10), Beijing 102413 (China)

    2016-02-10

    The extent of nucleosynthesis in models of type I X-ray bursts (XRBs) and the associated impact on the energy released in these explosive events are sensitive to nuclear masses and reaction rates around the {sup 64}Ge waiting point. Using the well known mass of {sup 64}Ge, the recently measured {sup 65}As mass, and large-scale shell model calculations, we have determined new thermonuclear rates of the {sup 64}Ge(p,γ){sup 65}As and {sup 65}As(p,γ){sup 66}Se reactions with reliable uncertainties. The new reaction rates differ significantly from previously published rates. Using the new data, we analyze the impact of the new rates and the remaining nuclear physics uncertainties on the {sup 64}Ge waiting point in a number of representative one-zone XRB models. We find that in contrast to previous work, when all relevant uncertainties are considered, a strong {sup 64}Ge rp-process waiting point cannot be ruled out. The nuclear physics uncertainties strongly affect XRB model predictions of the synthesis of {sup 64}Zn, the synthesis of nuclei beyond A = 64, the energy generation, and the burst light curve. We also identify key nuclear uncertainties that need to be addressed to determine the role of the {sup 64}Ge waiting point in XRBs. These include the remaining uncertainty in the {sup 65}As mass, the uncertainty of the {sup 66}Se mass, and the remaining uncertainty in the {sup 65}As(p,γ){sup 66}Se reaction rate, which mainly originates from uncertain resonance energies.

  11. Exploiting dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS) for sequential determination of trace elements in blood using a dilute-and-shoot procedure.

    Science.gov (United States)

    Batista, Bruno Lemos; Rodrigues, Jairo Lisboa; Nunes, Juliana Andrade; Souza, Vanessa Cristina de Oliveira; Barbosa, Fernando

    2009-04-20

    Inductively coupled plasma mass spectrometry with quadrupole (q-ICP-MS) and dynamic reaction cell (DRC-ICP-MS) were evaluated for sequential determination of As, Cd, Co, Cr, Cu, Mn, Pb, Se, Tl, V and Zn in blood. The method requires as little as 100 microL of blood. Prior to analysis, samples (100 microL) were diluted 1:50 in a solution containing 0.01% (v/v) Triton X-100 and 0.5% (v/v) nitric acid. The use of the DRC was only mandatory for Cr, Cu, V and Zn. For the other elements the equipment may be operated in a standard mode (q-ICP-MS). Ammonia was used as reaction gas. Selection of best flow rate of ammonium gas and optimization of the quadrupole dynamic band-pass tuning parameter (RPq) were carried out, using a ovine base blood for Cr and V and a synthetic matrix solution (SMS) for Zn and Cu diluted 1:50 and spiked to contain 1 microg L(-1) of each element. Method detection limits (3 s) for (75)As, (114)Cd, (59)Co, (51)Cr, (63)Cu (55)Mn, (208)Pb, (82)Se, (205)Tl, (51)V, and (64)Zn were 14.0, 3.0, 11.0, 7.0, 280, 9.0, 3.0, 264, 0.7, 6.0 and 800 ng L(-1), respectively. Method validation was accomplished by the analysis of blood Reference Materials produced by the L'Institut National de Santé Publique du Quebec (Canada).

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

    Energy Technology Data Exchange (ETDEWEB)

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

    Science.gov (United States)

    Balistrieri, Laurie S.; Borrok, David M.; Wanty, Richard B.; Ridley, W. Ian

    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 (αsoln-solid) are 0.99927 ± 0.00008 for Cu and 0.99948 ± 0.00004 for Zn or, alternately, the separation factors (Δsoln-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).

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

    Science.gov (United States)

    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).

  15. Systematics of gamma decay through low-lying vibrational levels of even--even nuclei excited by (p,p') and (n,n') reactions

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, R.P.

    1977-06-30

    A series of experiments was performed in which gamma-ray spectra were measured, using a Ge(Li) detector, for incident 7 to 26-MeV protons on the even-even vibrational nuclei /sup 56/Fe, /sup 62/Ni, /sup 64/Zn, /sup 108/Pd, /sup 110/Cd, /sup 114/Cd, /sup 116/Cd, /sup 116/Sn, /sup 120/Sn, and /sup 206/Pb, and for incident 14-MeV neutrons on natural Fe, Ni, Zn, Cd, Sn, and Pb. These measurements yielded gamma-ray cross sections from which it was inferred that almost all of the gamma cascades from (p,p') and (n,n') reactions passed down through the first 2/sup +/ levels. Consequently, the strength of the 2/sup +/ ..-->.. 0/sup +/ gamma transitions were found to be an indirect measure of the (p,p') or (n,n') cross sections. Several types of nuclear model calculations were performed and compared with experimental results. These calculations included coupled-channel calculations to reproduce the direct, collective excitation of the low-lying levels, and statistical plus pre-equilibrium model calculations to reproduce the (p,p') and the (n,n') cross sections for comparison with the 2/sup +/ ..-->.. 0/sup +/ gamma measurements. The agreement between calculation and experiment was generally good except at high energies, where pre-equilibrium processes dominate (i.e. around 26-MeV). Here discrepancies between calculations from the two different pre-equilibrium models and between the data and the calculations were found. Significant isospin mixing of T/sub greater than/ into T/sub less than/ states was necessary in order to have the calculations match the data for the (p,p') reactions, up to about 18-MeV.

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

    Science.gov (United States)

    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.

  17. A search for nickel isotopic anomalies in iron meteorites and chondrites

    Science.gov (United States)

    Chen, J. H.; Papanastassiou, D. A.; Wasserburg, G. J.

    2009-03-01

    We report Ni isotopic data, for 58,60-62Ni, on (1) FeNi metal and sulfides in different groups of iron meteorites, (2) sulfides and a whole rock sample of the St. Séverin chondrite, and (3) chondrules from the Chainpur chondrite. We have developed improved, Multiple-Collector, Positive ion Thermal Ionization Mass Spectrometric (MC-PTIMS) techniques, with Ni + ionization efficiency at 1‰, and chemical separation techniques for Ni which reduce mass interferences to the 1 ppm level, so that no mass interference corrections need be applied, except for 64Ni (from 64Zn, at the 0.1‰ level), for which we do not report results. We normalize the data to 62Ni/ 58Ni to correct for mass dependent isotope fractionation. No evidence was found for resolved radiogenic or general Ni isotope anomalies at the resolution levels of 0.2 and 0.5 ɛu (ɛu = 0.01%) for 60Ni/ 58Ni and 61Ni/ 58Ni, respectively. From the 56Fe/ 58Ni ratios and ɛ( 60Ni/ 58Ni) values, we calculate upper limits for the initial value of ( 60Fe/ 56Fe) 0 of (a) Toluca and Odessa by Quitté et al. [Quitté G., Meier M., Latkoczy C., Halliday A. N., and Gunther D., (2006). Nickel isotopes in iron meteorites-nucleosynthetic anomalies in sulfides with no effects in metals and no trace of 60Fe. Earth Planet. Sci. Lett. 242, 16-25]. Hence, we find no need for specialized physical-chemical planetary processes for the preservation of different Ni isotope compositions, between FeNi metal and sulfides in the same iron meteorites, as proposed by the above reports nor for complex astrophysical scenarios to provide the very peculiar Ni isotope anomalies reported by these workers for sulfides.

  18. Systemic translocation of (70)zinc: kinetics following intratracheal instillation in rats.

    Science.gov (United States)

    Wallenborn, J Grace; Kovalcik, Kasey D; McGee, John K; Landis, Matthew S; Kodavanti, Urmila P

    2009-01-01

    Mechanisms of particulate matter (PM)-induced cardiotoxicity are not fully understood. Direct translocation of PM-associated metals, including zinc, may mediate this effect. We hypothesized that following a single intratracheal instillation (IT), zinc directly translocates outside of the lungs, reaching the heart. To test this, we used high resolution magnetic sector field inductively coupled plasma mass spectrometry to measure levels of five stable isotopes of zinc ((64)Zn, (66)Zn, (67)Zn, (68)Zn, (70)Zn), and copper in lungs, plasma, heart, liver, spleen, and kidney of male Wistar Kyoto rats (13 weeks old, 250-300 g), 1, 4, 24, and 48 h following a single IT or oral gavage of saline or 0.7 micromol/rat (70)Zn, using a solution enriched with 76.6% (70)Zn. Natural abundance of (70)Zn is 0.62%, making it an easily detectable tracer following exposure. In IT rats, lung (70)Zn was highest 1 h post IT and declined by 48 h. Liver endogenous zinc was increased 24 and 48 h post IT. (70)Zn was detected in all extrapulmonary organs, with levels higher following IT than following gavage. Heart (70)Zn was highest 48 h post IT. Liver, spleen and kidney (70)Zn peaked 4 h following gavage, and 24 h following IT. (70)Zn IT exposure elicited changes in copper homeostasis in all tissues. IT instilled (70)Zn translocates from lungs into systemic circulation. Route of exposure affects (70)Zn translocation kinetics. Our data suggests that following pulmonary exposure, zinc accumulation and subsequent changes in normal metal homeostasis in the heart and other organs could induce cardiovascular injury.

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Systematics of gamma decay through low-lying vibrational levels of even--even nuclei excited by (p,p') and (n,n') reactions

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, R.P.

    1977-06-30

    A series of experiments was performed in which gamma-ray spectra were measured, using a Ge(Li) detector, for incident 7 to 26-MeV protons on the even-even vibrational nuclei /sup 56/Fe, /sup 62/Ni, /sup 64/Zn, /sup 108/Pd, /sup 110/Cd, /sup 114/Cd, /sup 116/Cd, /sup 116/Sn, /sup 120/Sn, and /sup 206/Pb, and for incident 14-MeV neutrons on natural Fe, Ni, Zn, Cd, Sn, and Pb. These measurements yielded gamma-ray cross sections from which it was inferred that almost all of the gamma cascades from (p,p') and (n,n') reactions passed down through the first 2/sup +/ levels. Consequently, the strength of the 2/sup +/ ..-->.. 0/sup +/ gamma transitions were found to be an indirect measure of the (p,p') or (n,n') cross sections. Several types of nuclear model calculations were performed and compared with experimental results. These calculations included coupled-channel calculations to reproduce the direct, collective excitation of the low-lying levels, and statistical plus pre-equilibrium model calculations to reproduce the (p,p') and the (n,n') cross sections for comparison with the 2/sup +/ ..-->.. 0/sup +/ gamma measurements. The agreement between calculation and experiment was generally good except at high energies, where pre-equilibrium processes dominate (i.e. around 26-MeV). Here discrepancies between calculations from the two different pre-equilibrium models and between the data and the calculations were found. Significant isospin mixing of T/sub greater than/ into T/sub less than/ states was necessary in order to have the calculations match the data for the (p,p') reactions, up to about 18-MeV.

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

    Science.gov (United States)

    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. RoSiB - a 4{pi} silicon ball for charged-particle detection in EUROBALL

    Energy Technology Data Exchange (ETDEWEB)

    Pausch, G.; Prade, H.; Sobiella, M.; Schnare, H.; Schwengner, R.; Kaeubler, L.; Borcan, C.; Ortlepp, H.-G.; Oehmichen, U.; Grawe, H.; Schubart, R.; Gerl, J.; Cederkaell, J.; Johnson, A.; Kerek, A.; Klamra, W.; Moszynski, M. E-mail: marek@ipj.gov.pl; Wolski, D.; Kapusta, M.; Axelsson, A.; Weiszflog, M.; Haertlein, T.; Pansegrau, D.; De Angelis, G.; Ashrafi, S.; Likar, A.; Lipoglavsek, M

    2000-04-01

    A 4{pi} silicon ball for detection and identification of light charged particles in large multidetector {gamma}-arrays as EUROBALL is presented. The design is based on a N=42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive material for {gamma}-rays is minimized to the detector thickness of 300 or 500 {mu}m and a 0.63 mm ceramic backing. The geometrical coverage is designed for about 90% of 4{pi}. A pulse shape discrimination method with totally depleted detectors working in the reverse mount allows identifying protons and {alpha}-particles above an energy threshold of about 2 MeV. The performances of the ball were tested at the tandem - booster accelerator combination of the MPI Heidelberg in two experiments using the high-recoil reaction of 228 MeV {sup 58}Ni+{sup 46}Ti and the low-recoil reaction of 95 MeV {sup 16}O+{sup 58}Ni. The two-dimensional spectra of zero-crossing (ZC) versus energy confirmed an excellent discrimination of protons and {alpha}-particles in all the detectors at different angles. The energy spectra of protons and {alpha}-particles measured in the experiments are presented, too. The {gamma}-spectra measured in coincidence with various combinations of emitted particles showed a high selectivity of the ball. The reduced total efficiency for protons of 59% and 55% and {alpha}-particles of 44% and 32% measured in a nuclear spectroscopy application is analyzed in a Monte-Carlo simulation (GEANT). It is due to a combined influence of a thick target needed to stop the recoiling residual nuclei and thick absorbers needed to protect the Si-detectors from scattered beam. The results along with the GEANT extrapolation to optimum experimental conditions confirm that RoSiB is a highly efficient and selective device for identification of rare reaction channels with heavy ions.

  3. Temperature-dependent wear mechanisms for magnetron-sputtered AlTiTaN hard coatings.

    Science.gov (United States)

    Khetan, Vishal; Valle, Nathalie; Duday, David; Michotte, Claude; Mitterer, Christian; Delplancke-Ogletree, Marie-Paule; Choquet, Patrick

    2014-09-10

    AlTiTaN coatings have been demonstrated to have high thermal stability at temperatures up to 900 °C. It has been speculated that the high oxidation resistance promotes an improved wear resistance, specifically for dry machining applications. This work reports on the influence of temperature up to 900 °C on the wear mechanisms of AlTiTaN hard coatings. DC magnetron-sputtered coatings were obtained from an Al(46)Ti(42)Ta(12) target, keeping the substrate bias at -100 V and the substrate temperature at 265 °C. The coatings exhibited a single-phase face-centered cubic AlTiTaN structure. The dry sliding tests revealed predominant abrasion and tribo-oxidation as wear mechanisms, depending on the wear debris formed. At room temperature, abrasion leading to surface polishing was observed. At 700 and 800 °C, slow tribo-oxidation and an amorphous oxide formed reduced the wear rate of the coating compared to room temperature. Further, an increase in temperature to 900 °C increased the wear rate significantly due to fast tribo-oxidation accompanied by grooving. The friction coefficient was found to decrease with temperature increasing from 700 to 900 °C due to the formation of oxide scales, which reduce adhesion of asperity contacts. A relationship between the oxidation and wear mechanisms was established using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, surface profilometry, confocal microscopy, and dynamic secondary ion mass spectrometry.

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

    Science.gov (United States)

    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

  5. Four-body continuum-discretized coupled-channels calculations applied to {sup 6}He reactions

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Gallardo, M. [Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain). Inst. de Estructura de la Materia; Arias, J.M.; Gomez-Camacho, J.M.; Moro, A.M. [Universidad de Sevilla (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Thompson, I.J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Physical Science Directorate; Tostevin, J.A. [University of Surrey, Guildford (United Kingdom). Dept. of Physics

    2010-07-01

    Full text. The scattering of a weakly bound three-body system by a target is discussed. The continuum-discretized coupled-channels (CDCC) framework, recently extended to four-body reactions (three-body projectile plus target), is used for the scattering calculations. Two different methods are used to discretized the three-body continuum of the projectile. In the first case, we make use of a Pseudo-State (PS) method in which the states of the projectile are represented by the eigenstates of its internal Hamiltonian in a truncated basis of square-integrable functions. In particular, we use the transformed harmonic oscillator (THO) method, in which the PS basis is obtained by applying a local scale transformation to the Harmonic Oscillator basis. In the second case, we applied the binning procedure that has just been extended to three-body projectiles. This discretization method requires to calculate first the true continuum of the projectile and then this continuum is discretized making bins or packages of energy. This has been the method used for many years in standard three-body (two-body projectile plus target) CDCC calculations. Its extension to three-body projectiles uses the eigenchannel expansion of the three-body S-matrix. We applied this formalism to several reactions induced by the Borromean nucleus {sup 6}He at different energies, namely {sup 6}He+{sup 9}Be at 16.2 MeV, {sup 6}He+{sup 64}Zn at 13.6 MeV, {sup 6}He+{sup 120}Sn at 17.4 MeV, and {sup 6}He+{sup 208}Pb at 22 MeV. Four-body CDCC calculations for elastic and breakup observables are presented for these reactions comparing both discretization methods, THO and binning. The effect of the mass of the target, which is clearly related to the influence of Coulomb couplings, is investigated. The elastic cross sections are also compared to existing experimental data. (author)

  6. Zinc and volatile element loss during planetary magma ocean phases

    Science.gov (United States)

    Dhaliwal, Jasmeet K.; Day, James M. D.; Moynier, Frédéric

    2016-10-01

    Zinc is a moderately volatile element and a key tracer of volatile depletion on planetary bodies due to lack of significant isotopic fractionation under high-temperature processes. Terrestrial basalts have δ66Zn values similar to some chondrites (+ 0.15 to 0.3‰ where [{66Zn/64Znsample/66Zn/64ZnJMC-Lyon-1} × 1000]) and elevated Zn concentrations (100 ppm). Lunar mare basalts yield a mean δ66Zn value of +1.4 ± 0.5‰ and have low Zn concentrations (~2 ppm). Late-stage lunar magmatic products, such as ferroan anorthosite, Mg-suite and Alkali suite rocks exhibit heavier δ66Zn values (+3 to +6‰). The heavy δ66Zn lunar signature is thought to reflect evaporative loss and fractionation of zinc, either during a giant impact or in a magma ocean phase.We explore conditions of volatile element loss within a lunar magma ocean (LMO) using models of Zn isotopic fractionation that are widely applicable to planetary magma oceans. For the Moon, our objective was to identify conditions that would yield a δ66Zn signature of ~ +1.4‰ within the mantle, assuming a terrestrial mantle zinc starting composition.We examine two cases of zinc evaporative fractionation: (1) lunar surface zinc fractionation that was completed prior to LMO crystallization and (2) lunar surface zinc fractionation that was concurrent with LMO crystallization. The first case resulted in a homogeneous lunar mantle and the second case yielded a stratified lunar mantle, with the greatest zinc isotopic enrichment in late-stage crystallization products. This latter case reproduces the distribution of zinc isotope compositions in lunar materials quite well.We find that hydrodynamic escape was not a dominant process in losing Zn, but that erosion of a nascent lunar atmosphere, or separation of condensates into a proto-lunar crust are possible. While lunar volatile depletion is still possible as a consequence of the giant impact, this process cannot reproduce the variable δ66Zn found in the Moon. Outgassing

  7. Study of the {sup 6}He+{sup 9}Be reaction at low energies

    Energy Technology Data Exchange (ETDEWEB)

    Pires, K.C.C.; Lichtenthaeler, R.; Lepine-Szily, A. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica. Dept. de Fisica Nuclear

    2010-07-01

    Full text: Elastic scattering measurements of the exotic {sup 6}He nuclei on heavy and medium mass targets (eg. {sup 6}He+{sup 208}Pb, {sup 6}He+{sup 64}Zn) show large values of the reaction cross section compared with reactions induced by stable weakly bound projectiles. This phenomenon could be a consequence of the halo nature of the {sup 6}He, which can easily breakup in the Coulomb and nuclear fields of the target. In this work we present new scattering data of the light system {sup 6}He+{sup 9}Be at E{sub lab} = 16:2 MeV and E{sub lab} = 21:3 MeV. For this light system the Coulomb interaction is small compared to the nuclear and the Coulomb breakup of the projectile is expected to have little influence. The measurements have been performed at the Pelletron Laboratory of the Institute of Physics of the University of Sao Paulo, Brazil, using the RIBRAS facility. The RIBRAS system consists of two superconducting solenoids used to focalize and select the radioactive secondary beam. The {sup 6}He beam was produced using the {sup 9}Be({sup 7}Li,{sup 6}He) production reaction. The detection system consisted of four {Delta}E-E Silicon telescopes, with 20{mu}m and 1000{mu}m thickness respectively which allow to separate the {sup 6}He particles from the {sup 7}Li beam contaminant and light particles. We performed optical model, coupled channels and CDCC calculations. In the last one, the continuum spectrum was discretized in energy bins. The comparison between the experimental data and the optical model and CDCC calculations allow us to conclude that even for these light targets the breakup of the projectile and the coupling to the 2{sup +} resonance of {sup 6}He nucleus is very important. Furthermore, using the coupled channels method, we studied the effect of excitation of the target explicitly, using a collective model for describe the coupling to the first states of {sup 9}Be nucleus. We found that the coupling to these states also affects the elastic scattering

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

    Directory of Open Access Journals (Sweden)

    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

  9. Medical applications of Cu, Zn, and S isotope effects.

    Science.gov (United States)

    Albarede, Francis; Télouk, Philippe; Balter, Vincent; Bondanese, Victor P; Albalat, Emmanuelle; Oger, Philippe; Bonaventura, Paola; Miossec, Pierre; Fujii, Toshiyuki

    2016-10-01

    This review examines recent applications of stable copper, zinc and sulfur isotopes to medical cases and notably cancer. The distribution of the natural stable isotopes of a particular element among coexisting molecular species varies as a function of the bond strength, the ionic charge, and the coordination, and it also changes with kinetics. Ab initio calculations show that compounds in which a metal binds to oxygen- (sulfate, phosphate, lactate) and nitrogen-bearing moieties (histidine) favor heavy isotopes, whereas bonds with sulfur (cysteine, methionine) favor light isotopes. Oxidized cations (e.g., Cu(ii)) and low coordination numbers are expected to favor heavy isotopes relative to their reduced counterparts (Cu(i)) and high coordination numbers. Here we discuss the first observations of Cu, Zn, and S isotopic variations, three elements closely related along multiple biological pathways, with emphasis on serum samples of healthy volunteers and of cancer patients. It was found that heavy isotopes of Zn and to an even greater extent Cu are enriched in erythrocytes relative to serum, while the difference is small for sulfur. Isotopic variations related to age and sex are relatively small. The (65)Cu/(63)Cu ratio in the serum of patients with colon, breast, and liver cancer is conspicuously low relative to healthy subjects. The characteristic time over which Cu isotopes may change with disease progression (a few weeks) is consistent with both the turnover time of the element and albumin half-life. A parallel effect on sulfur isotopes is detected in a few un-medicated patients. Copper in liver tumor tissue is isotopically heavy. In contrast, Zn in breast cancer tumors is isotopically lighter than in healthy breast tissue. (66)Zn/(64)Zn is very similar in the serum of cancer patients and in controls. Possible reasons for Cu isotope variations may be related to the cytosolic storage of Cu lactate (Warburg effect), release of intracellular copper from cysteine

  10. Lithium-bearing fluor-arfvedsonite from Hurricane Mountain, New Hampshire: A crystal-chemical study

    Science.gov (United States)

    Hawthorne, F.C.; Oberti, R.; Ottolini, L.; Foord, E.E.

    1996-01-01

    The structures of two crystals of Li-bearing fluor-arfvedsonite (1) (K0.32Na0.68)Na2(Li0.48Fe 2+2.83Mn2+0.10Zn 0.06Fe3+1.46Ti0.07) (Si7.88Al0.12)O22[Fu1.15(OH) 0.85] and (2) (K0.25Na0.75)Na2(Li0.48Fe 2+2.84Mn2+0.11Zn 0.05Fe3+1.45Ti0.07)(Si 7.89Al0.11)O22[F1.35(OH) 0.65] from a granitic pegmatite, Hurricane Mountain, New Hampshire, have been refined to R indices of 1.5(1.6)% based on 1380(1387) reflections measured with MoK?? X-radiation. The unit cell parameters are (1) a 9.838(4), b 17.991(6), c 5.315(2) A??, 103.78(3)??, V 913.7 A??3 and (2) a 9.832(3), b 17.990(7), c 5.316(3) A??, ?? 103.79(3)??, V 913.2 A??3. Site-scattering refinement shows Li to be completely ordered at the M(3) site in these crystals. The amphibole composition is intermediate between fluor-arfvedsonite and fluor-ferro-leakeite with a small component (???10%) of fluor-ferro-ferri-nybo??ite. These amphibole crystals project into miarolitic cavities in a pegmatitic phase of a riebeckite granite. The early-crystallizing amphibole is close to fluor-ferro-leakeite in composition, but becomes progressively depleted in Li and F as crystals project out into miarolitic cavities; the final amphibole to crystallize is a fibrous Li-poor riebeckite. Li plays a significant role in late-stage fractionation involving the crystallization of alkali amphibole in peralkaline granitic environments.

  11. Chemical durability of hollandite ceramic for conditioning cesium

    Energy Technology Data Exchange (ETDEWEB)

    Angeli, Frederic [CEA Marcoule, DEN/DTCD/SECM/LCLT, F-30207 Bagnols-sur-Ceze (France)], E-mail: frederic.angeli@cea.fr; McGlinn, Peter [ANSTO, New Illawarra Road, Menai, PMB1, NSW 2234 (Australia); Frugier, Pierre [CEA Marcoule, DEN/DTCD/SECM/LCLT, F-30207 Bagnols-sur-Ceze (France)

    2008-10-15

    The aqueous corrosion behavior of Cs-doped hollandite ceramic (BaCs{sub 0.28}Fe{sub 0.82}Al{sub 1.46}Ti{sub 5.72}O{sub 16}) was studied using several different static experimental protocols, with leachants of varying pH, and at different surface area to volume ratios, for periods ranging from six months to three years. All leach tests were carried out at 90 deg. C. X-ray diffraction (XRD) and scanning electron microscopy (SEM), coupled with energy dispersive X-ray spectroscopy (EDS), were used to characterize the surfaces of the hollandite before and after leaching. The most pronounced elemental releases, and corresponding changes to surface composition and microstructure, was evident at low pH, in particular pH 1. Cs and Ba releases were highest at low pH, with surface alteration exhibited by the formation of secondary rutile (prevalent at pH 1) and Al- and Ba-depleted hollandite (prevalent at pH 2). After rapid initial Cs release, the alteration rate was extremely low over the pH range from 2 to 10, as well as in pure water experiments with a sample-surface-area-to-solution-volume ratio ranging from 0.1 cm{sup -1} to 1200 cm{sup -1}. The rates were about 10{sup -5} g m{sup -2} d{sup -1}, corresponding to alteration thicknesses of a few nanometers per year. Higher rates (5 x 10{sup -3} g m{sup -2} d{sup -1}) were observed only under very acidic conditions (pH 1). Congruency in Cs and Ba releases occurred only at pH 1, with incongruency between the two elements increasing with increasing pH. There were no apparent solubility constraints on Cs releases regardless of the SA/V ratio, whereas geochemical modeling suggested that Ba releases could have been affected by the formation of BaCO{sub 3}, particularly at high SA/V ratios. Extended leaching (with the leachant renewed once after 261 days of leaching) confirmed the high durability of hollandite with altered thicknesses of less than one nanometer per year over the last two years. Whilst Cs depletion of the

  12. Chemical durability of hollandite ceramic for conditioning cesium

    Science.gov (United States)

    Angeli, Frédéric; McGlinn, Peter; Frugier, Pierre

    2008-10-01

    The aqueous corrosion behavior of Cs-doped hollandite ceramic (BaCs 0.28Fe 0.82Al 1.46Ti 5.72O 16) was studied using several different static experimental protocols, with leachants of varying pH, and at different surface area to volume ratios, for periods ranging from six months to three years. All leach tests were carried out at 90 °C. X-ray diffraction (XRD) and scanning electron microscopy (SEM), coupled with energy dispersive X-ray spectroscopy (EDS), were used to characterize the surfaces of the hollandite before and after leaching. The most pronounced elemental releases, and corresponding changes to surface composition and microstructure, was evident at low pH, in particular pH 1. Cs and Ba releases were highest at low pH, with surface alteration exhibited by the formation of secondary rutile (prevalent at pH 1) and Al- and Ba-depleted hollandite (prevalent at pH 2). After rapid initial Cs release, the alteration rate was extremely low over the pH range from 2 to 10, as well as in pure water experiments with a sample-surface-area-to-solution-volume ratio ranging from 0.1 cm -1 to 1200 cm -1. The rates were about 10 -5 g m -2 d -1, corresponding to alteration thicknesses of a few nanometers per year. Higher rates (5 × 10 -3 g m -2 d -1) were observed only under very acidic conditions (pH 1). Congruency in Cs and Ba releases occurred only at pH 1, with incongruency between the two elements increasing with increasing pH. There were no apparent solubility constraints on Cs releases regardless of the SA/ V ratio, whereas geochemical modeling suggested that Ba releases could have been affected by the formation of BaCO 3, particularly at high SA/ V ratios. Extended leaching (with the leachant renewed once after 261 days of leaching) confirmed the high durability of hollandite with altered thicknesses of less than one nanometer per year over the last two years. Whilst Cs depletion of the hollandite surface was evidenced when leachates were replenished with the

  13. Isotopic and elemental abundances of copper and zinc in lunar samples, Zagami, Pele’s hairs, and a terrestrial basalt

    Science.gov (United States)

    Herzog, G. F.; Moynier, F.; Albarède, F.; Berezhnoy, A. A.

    2009-10-01

    We used ICP-MS to measure the elemental concentrations and isotopic abundances of Cu and Zn in: nine Ti-rich lunar basalts (10017, 10022, 10024, 10057, 70215, 71055, 74255, 75055, and 75075); size-separated samples prepared by sieving of pyroclastic black glass 74001, orange glass 74022, and the lunar soils 15021, 15231, 70181, and 79221; a basalt from the Piton des Neiges volcano, Reunion Island; two samples of Pele's hairs from the Nyiragongo volcano, Democratic Republic of Congo, and the martian meteorite Zagami. The isotopic fractionation of zinc in lunar basalts and Zagami is mass dependent relative to a terrestrial standard (JMC 400882B). These and published results imply that lunar, terrestrial, meteoritic, and perhaps martian zinc all come from one or more reservoirs linked by mass-dependent fractionation processes. Relative to terrestrial basalts, Ti-rich lunar basalts are enriched in the heavier isotopes of Cu and Zn: we find for Ti-rich lunar basalts the following ranges and averages ±1 - σ (‰): δ 65Cu/ 63Cu ≡ δ 65Cu, 0.1-1.4, 0.5 ± 0.1‰ ( N = 7); δ 66Zn/ 64Zn ≡ δ 66Zn = 0.2-1.9, 1.2 ± 0.2‰ ( N = 8; 10017 excluded). For two terrestrial samples, we find δ 66Zn ˜ +0.3‰ and δ 65Cu ˜ 0‰, which are consistent with published values. The differences between the lunar basalts and terrestrial basalts could reflect minor, planetary-scale vaporization or igneous processes on the Moon. Data for size separates of the pyroclastic glasses 74001 and 74220 confirm the well-known surface correlation of Cu and Zn, but modeling calculations reveal no sharp differences between either the elemental ratios or the isotopic composition of grain interiors and exteriors. The absence of such differences indicates that the isotopic compositions for bulk samples are dominated by a light-isotope-rich surface component. Data for size separates of lunar soils also confirm the surface correlation of Cu and Zn, but an enrichment of heavy rather than light

  14. Batisite, Na2BaTi2(Si4O12)O2, from Inagli massif, Aldan, Russia: crystal-structure refinement and high-temperature X-ray diffraction study

    Science.gov (United States)

    Zolotarev, Andrey A.; Zhitova, Elena S.; Gabdrakhmanova, Faina A.; Krzhizhanovskaya, Maria G.; Zolotarev, Anatoly A.; Krivovichev, Sergey V.

    2017-02-01

    The crystal structure of batisite, Na2BaTi2 (Si4O12)O2, from the Inagli massif (Aldan, Yakutia, Russia) was refined to R 1 = 0.032 for 1449 unique observed reflections. The mineral is orthorhombic, Imma, a = 8.0921(5), b = 10.4751(7), c = 13.9054(9) Å, V = 1178.70(13) Å3. The mineral is based upon three-dimensional titanosilicate framework consisting of chains of corner-sharing MO6 octahedra (M = Ti, Nb, Fe and Zr) and vierer chains of corner-sharing SiO4 tetrahedra. Both chains are parallel to the a axis and are linked by sharing peripheral O atoms. The octahedral chains display disorder of M atoms and bridging O sites related to the out-of-center distortion of octahedral geometry around Ti4+ cations. Electron microprobe analysis gives SiO2 39.46, TiO2 24.66, BaO 21.64, Na2O 7.56, K2O 4.38, Fe2O3 0.90, ZrO2 0.66, Nb2O5 0.36, (H2O)calc 0.58, sum 99.76 wt%. The seven strongest X-ray powder-diffraction lines [listed as d in Å (I) hkl] are: 8.39 (94) 011, 3.386 (56) 031, 3.191 (36) 123, 2.910 (46) 222, 2.896 (100) 024, 2.175 (45) 035, 1.673 (57) 055. The thermal behaviour of batisite in the temperature range from 25 to 950 °C was studied using high-temperature powder X-ray diffraction. The thermal expansion coefficients along the principal crystallographic axes are: α a = 14.4 × 10-6, α b = 8.7 × 10-6, α c = 8.4 × 10-6, α V = 31.5 °C-1 for the temperature range 25-500 °C and α a = 19.6 × 10-6, α b = 9.1 × 10-6, α c = 8.8 × 10-6, α V = 37.6 °C-1 for the temperature range 500-900 °C. The direction of maximal thermal expansion is parallel to the chains of both MO6 octahedra and SiO4 tetrahedra, which can be explained by the stretching of silicate chains due to the increasing thermal vibrations of the Ba2+ cations. At 1000 °C, the titanosilicate framework in batisite collapses with the formation of fresnoite, Ba2TiSi2O7O.