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Sample records for even-even neutron-deficient polonium

  1. Shape coexistence measurements in even-even neutron-deficient polonium isotopes by Coulomb excitation, using REX-ISOLDE and the Ge MINIBALL array

    CERN Multimedia

    Butler, P; Bastin, B; Kruecken, R; Voulot, D; Rahkila, P J; Orr, N A; Srebrny, J; Grahn, T; Clement, E; Paul, E S; Gernhaeuser, R A; Dorsival, A; Diriken, J V J; Huyse, M L; Iwanicki, J S

    The neutron-deficient polonium isotopes with two protons outside the closed Z=82 shell represent a set of nuclei with a rich spectrum of nucleus structure phenomena. While the onset of the deformation in the light Po isotopes is well established experimentally, questions remain concerning the sign of deformation and the magnitude of the mixing between different configurations. Furthermore, controversy is present with respect to the transition from the vibrational-like character of the heavier Po isotopes to the shape coexistence mode observed in the lighter Po isotopes. We propose to study this transition in the even-mass neutron-deficient $^{198,200,202}$Po isotopes by using post-accelerated beams from REX-ISOLDE and "safe"-energy Coulomb excitation. $\\gamma$- rays will be detected by the MINIBALL array. The measurements of the Coulomb excitation differential cross section will allow us to deduce both the transition and diagonal matrix elements for these nuclei and, combined with lifetime measurements, the s...

  2. Shape coexistence in the neutron-deficient even-even (182-188)Hg isotopes studied via coulomb excitation.

    Science.gov (United States)

    Bree, N; Wrzosek-Lipska, K; Petts, A; Andreyev, A; Bastin, B; Bender, M; Blazhev, A; Bruyneel, B; Butler, P A; Butterworth, J; Carpenter, M P; Cederkäll, J; Clément, E; Cocolios, T E; Deacon, A; Diriken, J; Ekström, A; Fitzpatrick, C; Fraile, L M; Fransen, Ch; Freeman, S J; Gaffney, L P; García-Ramos, J E; Geibel, K; Gernhäuser, R; Grahn, T; Guttormsen, M; Hadinia, B; Hadyńska-Kle K, K; Hass, M; Heenen, P-H; Herzberg, R-D; Hess, H; Heyde, K; Huyse, M; Ivanov, O; Jenkins, D G; Julin, R; Kesteloot, N; Kröll, Th; Krücken, R; Larsen, A C; Lutter, R; Marley, P; Napiorkowski, P J; Orlandi, R; Page, R D; Pakarinen, J; Patronis, N; Peura, P J; Piselli, E; Rahkila, P; Rapisarda, E; Reiter, P; Robinson, A P; Scheck, M; Siem, S; Singh Chakkal, K; Smith, J F; Srebrny, J; Stefanescu, I; Tveten, G M; Van Duppen, P; Van de Walle, J; Voulot, D; Warr, N; Wenander, F; Wiens, A; Wood, J L; Zielińska, M

    2014-04-25

    Coulomb-excitation experiments to study electromagnetic properties of radioactive even-even Hg isotopes were performed with 2.85  MeV/nucleon mercury beams from REX-ISOLDE. Magnitudes and relative signs of the reduced E2 matrix elements that couple the ground state and low-lying excited states in Hg182-188 were extracted. Information on the deformation of the ground and the first excited 0+ states was deduced using the quadrupole sum rules approach. Results show that the ground state is slightly deformed and of oblate nature, while a larger deformation for the excited 0+ state was noted in Hg182,184. The results are compared to beyond mean field and interacting-boson based models and interpreted within a two-state mixing model. Partial agreement with the model calculations was obtained. The presence of two different structures in the light even-mass mercury isotopes that coexist at low excitation energy is firmly established.

  3. Deformation and mixing of co-existing shapes in the neutron-deficient polonium isotopes

    CERN Document Server

    AUTHOR|(CDS)2078559; Huyse, Mark

    The neutron-deficient polonium isotopes, with only 2 protons outside the Z = 82 shell closure, are situated in an interesting region of the nuclear chart. In the neighboring lead (Z = 82) and mercury (Z = 80) isotopes, experimental and theoretical efforts identified evidence of shape coexistence. Shape coexistence is the remarkable phenomenon in which two or more distinct types of deformation occur in states of the same angular momentum and similar excitation energy in a nucleus. The neutron-deficient polonium isotopes have also been studied intensively, experimentally as well as theoretically. The closed neutron-shell nucleus 210Po (N = 126) manifests itself as a two-particle nucleus where most of the excited states can be explained by considering the degrees of freedom of the two valence protons outside of 208Pb. The near-constant behavior of the yrast 2+1 and 4+1 states in the isotopes with mass 200 ≤ A ≤ 208 can be explained by coupling the two valence protons to a vibrating lead core. 200Po seems to ...

  4. Coulomb excitation of neutron-deficient polonium isotopes studied at ISOLDE

    CERN Document Server

    Neven, Michiel

    The polonium isotopes represent an interesting region of the nuclear chart having only two protons outside the Z = 82 closed shell. These isotopes have already been extensively studied theoretically and experimentally. The heavier isotopes (A > 200) seem to follow a "regular seniority-type regime" while for the lighter isotopes (A < 200) a more collective behavior is observed. Many questions remain regarding the transition between these two regimes and the configuration mixing between quantum states. Experiments in the lighter polonium isotopes point to the presence of shape coexistence, however the phenomenon is not fully understood. A Coulomb excitation study of the polonium isotopes whereby the dynamic properties are investigated can provide helpful insights in understanding the shape coexistence phenomena. In this thesis $^{202}$Po was studied via Coulomb excitation. The $^{202}$Po isotope was part of an experimental campaign in which the $^{196,198,200,206}$Po isotopes were studied as well via Coulomb...

  5. Early onset of ground-state deformation in the neutron-deficient polonium isotopes

    CERN Document Server

    Cocolios, T E; Seliverstov, M D; Andreyev, A N; Antalic, S; Barzakh, A E; Bastin, B; Buscher, J; Darby, I G; Fedorov, D V; Fedosseyev, V N; Flanagan, K T; Franchoo, S; Fritzsche, S; Huber, G; Huyse, M; Keupers, M; Koster, U; Kudryavtsev, Yu; Mane, E; Marsh, B A; Molkanov, P L; Page, R D; Sjoedin, A M; Stefan, I; Van de Walle, J; Van Duppen, P; Venhart, M; Zemlyanoy, S G; Bender, M; Heenen, P H; 10.1103/PhysRevLett.106.052503

    2011-01-01

    In-source resonant ionization laser spectroscopy of the even-$A$ polonium isotopes $^{192-210,216,218}$Po has been performed using the $6p^37s$ $^5S_2$ to $6p^37p$ $^5P_2$ ($\\lambda=843.38$ nm) transition in the polonium atom (Po-I) at the CERN ISOLDE facility. The comparison of the measured isotope shifts in $^{200-210}$Po with a previous data set allows to test for the first time recent large-scale atomic calculations that are essential to extract the changes in the mean-square charge radius of the atomic nucleus. When going to lighter masses, a surprisingly large and early departure from sphericity is observed, which is only partly reproduced by Beyond Mean Field calculations.

  6. Collective description of magnetic properties of even-even nuclei

    International Nuclear Information System (INIS)

    Maruhn, V.

    1975-01-01

    The generalized collective model is modified by introducing a number of quadrupole deformations for protons and neutrons. The coupling potential is described by physical approaches, and the overall model is applied to even-even nuclei. (WL) [de

  7. Vibrational collective model for spheric even-even nuclei

    International Nuclear Information System (INIS)

    Cruz, M.T.F. da.

    1985-01-01

    A review is made on the evidences of collective motions in spherical even-even nuclei. The several multipole transitions occuring in such a nuclei are discussed. Some hypothesis which are necessary in order to build-up the model are presented. (L.C.) [pt

  8. Excited bands in even-even rare-earth nuclei

    International Nuclear Information System (INIS)

    Vargas, Carlos E.; Hirsch, Jorge G.

    2004-01-01

    The energetics of states belonging to normal parity bands in even-even dysprosium isotopes, and their B(E2) transition strengths, are studied using an extended pseudo-SU(3) shell model. States with pseudospin 1 are added to the standard pseudospin 0 space, allowing for a proper description of known excited normal parity bands

  9. Alpha Decay of Even-Even Superheavy Nuclei

    International Nuclear Information System (INIS)

    Oudih, M.R.; Hamza, Y.; Fellah, M.; Allal, N.H.; Fellah, M.; Allal, N.H.

    2011-01-01

    Alpha decay properties of even-even superheavy nuclei with 112.Z.120 have been investigated using the Hartree-Fock-Bogoliubov approach. The method is based on the SkP Skyrme interaction and the Lipkin-Nogami prescription for treating the pairing correlations. The alpha decay energies are extracted from the binding energies and then used for the calculation of the decay half-lives using a formula similar to that of Viola-Seaborg. The parameters of the formula were obtained through a least square fit to even-even heavy nuclei taken from the tables of Audi- Wapstra and some more recent references. The results are compared with other theoretical evaluations.

  10. Collective states of nonspherical deformable even--even nuclei

    International Nuclear Information System (INIS)

    Tartakovskii, V.K.

    1989-01-01

    A more correct method, as compared with some earlier studies, of finding the wave functions and corresponding energies of longitudinal quadrupole vibrations of nonspherical even--even nuclei is proposed. The wave functions and energies of collective motions in nuclei have been obtained in explicit form for a number of dependences of the potential energy of longitudinal vibrations V(β), including the dependence V(β), not previously used, of the most general form. Explicit dependences of the potential energy of transverse vibrations and the corresponding wave functions and eigenvalues for nuclear states with zero spins are proposed

  11. Multi-quasiparticle excitation: Extending shape coexistence in A∼190 neutron-deficient nuclei

    International Nuclear Information System (INIS)

    Shi Yue; Liu, H. L.; Xu, F. R.; Walker, P. M.

    2010-01-01

    Multi-quasiparticle high-K states in neutron-deficient mercury, lead, and polonium isotopes have been investigated systematically by means of configuration-constrained potential-energy-surface calculations. An abundance of high-K states is predicted with both prolate and oblate shapes, which extends the shape coexistence of the mass region. Well-deformed shapes provide good conditions for the formation of isomers, as exemplified in 188 Pb. Of particular interest is the prediction of low-lying 10 - states in polonium isotopes, which indicate long-lived isomers.

  12. Isotopic yield in cold binary fission of even-even 230-244U isotopes

    International Nuclear Information System (INIS)

    Cyriac, Annu; Krishnan, Sreejith; Santhosh, K.P.

    2017-01-01

    The binary fission of even-even 230-244 U isotopes has been studied using the concept of cold reaction valley which was introduced in relation to the structure of minima in the so called driving potential

  13. Anisotropy of favoured alpha transitions producing even-even deformed nuclei

    International Nuclear Information System (INIS)

    Tavares, O.A.P.

    1997-05-01

    The anisotropy in favoured alpha transitions which produce even-even deformed nuclei is discussed. A simple, Gamow's-like model which takes into account the quadrupole deformation of the product nucleus has been formulated to calculate the alpha decay half-life. It is assumed that before tunneling into a purely Coulomb potential barrier the two-body system oscillated isotropically, thus giving rise to an equivalent, average preferential polar direction θ 0 (referred to the symmetry axis of the ellipsoidal shape of the product nucleus) for alpha emission in favoured alpha transitions of even-even nuclei. (author)

  14. Present state and prospect of systematics for the properties of even-even nuclei

    International Nuclear Information System (INIS)

    Zhao Yumin; Gu Jinnan

    1993-01-01

    The study of systematics for the properties of even-even nuclei, which is a new research field in nuclei structure, is reviewed. The primary results, including systematic analysis of energy spectra and electromagnetic transition, and the empirical law extracted from experimental data, are presented. It is expected that there will be new developments in the next few years in this fields

  15. Search for α + core states in even-even Cr isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Souza, M.A. [Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo, SP (Brazil); Instituto Federal de Educacao, Ciencia e Tecnologia de Sao Paulo, Departamento de Mecanica, Sao Paulo, SP (Brazil); Miyake, H. [Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo, SP (Brazil)

    2017-07-15

    The α + core structure is investigated in even-even Cr isotopes from the viewpoint of the local potential model. The comparison of Q{sub α}/A values for even-even Cr isotopes and even-even A = 46, 54, 56, 58 isobars indicates that {sup 46}Cr and {sup 54}Cr are the most favorable even-even Cr isotopes for the α + core configuration. The ground state bands of the two Cr isotopes are calculated through a local α + core potential containing a nuclear term with (1 + Gaussian) x (W.S. + W.S.{sup 3}) shape. The calculated spectra give a very good description of most experimental {sup 46}Cr and {sup 54}Cr levels, including the 0{sup +} bandheads. The reduced α-widths, rms intercluster separations and B(E2) transition rates are determined for the ground state bands. The calculations reproduce the order of magnitude of the available experimental B(E2) values without using effective charges, indicate that the low-spin members of the ground state bands present a stronger α-cluster character, and point out that the {sup 46}Cr ground state band has a significant degree of α-clustering in comparison with {sup 44}Ti. The volume integral per nucleon pair and rms radius obtained for the α + {sup 50}Ti potential are consistent with those reported previously in the analysis of α elastic scattering on {sup 50}Ti. (orig.)

  16. Reduced widths of alpha -decay of near-magic even-even nuclei

    CERN Document Server

    Kar Yan, N

    1972-01-01

    Precision on-line investigations on the linear heavy-ion Berkeley accelerator, and on the CERN synchrophasotron were carried out recently on new alpha -emitters. The results obtained are analysed with a view to finding the degree of correspondence, or disagreement, with the authors' own ideas about alpha -decay processes. The discussion is confined to examining even isotopes of polonium, radon, radium and thorium Several theoretical and experimental plots are given of reduced widths of alpha -disintegration for different regions of shell filling and a comparison is made between barrier penetration coefficients, obtained by rigorous methods and with the aid of WKB- approximation, for /sup 212/Po, /sup 208/Po and /sup 212/Po isotopes. (24 refs).

  17. Study of neutron-deficient Sn isotopes

    International Nuclear Information System (INIS)

    Auger, G.

    1982-05-01

    The formation of neutron deficient nuclei by heavy ion reactions is investigated. The experimental technique is presented, and the results obtained concerning Sn et In isotopes reported: first excited states of 106 Sn, high spin states in 107 Sn and 107 In; Yrast levels of 106 Sn, 107 Sn, 108 Sn; study of neutron deficient Sn and In isotopes formed by the desintegration of the compound nucleus 112 Xe. All these results are discussed [fr

  18. Quartetting in even-even and odd-odd N=Z nuclei

    Science.gov (United States)

    Sambataro, M.; Sandulescu, N.

    2018-02-01

    We report on a microscopic description of even-even N = Z nuclei in a formalism of quartets. Quartets are four-body correlated structures characterized by isospin T and angular momentum J. We show that the ground state correlations induced by a realistic shell model interaction can be well accounted for in terms of a restricted set of T = 0 low-J quartets, the J = 0 one playing by far a leading role among them. A conceptually similar description of odd-odd self-conjugate nuclei is given in terms of two distinct families of building blocks, one formed by the same T = 0 quartets employed for the even-even systems and the other by collective pairs with either T = 0 or T = 1. Some applications of this formalism are discussed for nuclei in the sd shell.

  19. Microscopic description of average level spacing in even-even nuclei

    International Nuclear Information System (INIS)

    Huong, Le Thi Quynh; Hung, Nguyen Quang; Phuc, Le Tan

    2017-01-01

    A microscopic theoretical approach to the average level spacing at the neutron binding energy in even-even nuclei is proposed. The approach is derived based on the Bardeen-Cooper-Schrieffer (BCS) theory at finite temperature and projection M of the total angular momentum J , which is often used to describe the superfluid properties of hot rotating nuclei. The exact relation of the J -dependent total level density to the M -dependent state densities, based on which the average level spacing is calculated, was employed. The numerical calculations carried out for several even-even nuclei have shown that in order to reproduce the experimental average level spacing, the M -dependent pairing gaps as well as the exact relation of the J -dependent total level density formula should be simultaneously used. (paper)

  20. Multiphonon states in even-even spherical nuclei. Pt.1. Calculation of the overlap matrix

    International Nuclear Information System (INIS)

    Piepenbring, R.; Protasov, K.V.; Silvestre-Brac, B.

    1995-01-01

    The multiphonon method, previously developed for deformed nuclei is extended to the case of even-even spherical nuclei. Recursion formulae, well suited for numerical calculations are given for the overlap matrix elements. The method is illustrated for a single j-shell, where S-, D-, G-, .. phonons are introduced. In such an approach, the Pauli principle is fully and properly taken into account. ((orig.))

  1. Rotational-vibrational states of nonaxial deformable even-even nuclei

    International Nuclear Information System (INIS)

    Porodzinskii, Yu.V.; Sukhovitskii, E.Sh.

    1991-01-01

    The rotational-vibrational excitations of nonaxial even-even nuclei are studied on the basis of a Hamiltonian operator with five dynamical variables. Explicit forms of the wave functions and energies of the rotational-vibrational excitations of such nuclei are obtained. The experimental energies of excited positive-parity states of the 238 U nucleus and those calculated in terms of the model discussed in the article are compared

  2. Low-spin identical bands in neighboring odd-A and even-even nuclei

    International Nuclear Information System (INIS)

    Baktash, C.; Winchell, D.F.; Garrett, J.D.; Smith, A.

    1992-01-01

    A comprehensive study of odd-A rotational bands in normally deformed rare-earth nuclei indicates that a large number of seniority-one configurations (21% for odd-Z nuclei) at low spin have moments of inertia nearly identical to that of the seniority-zero configuration of the neighboring even-even nucleus with one less nucleon. It is difficult to reconcile these results with conventional models of nuclear pair correlation, which predict variations of about 15% in the moments of inertia of configurations differing by one unit in seniority

  3. Global set of quadrupole deformation parameters for even-even nuclei

    International Nuclear Information System (INIS)

    Raman, S.; Nestor, C.W. Jr.

    1986-01-01

    A compilation of experimental results has been completed for the reduced electric quadrupole transition probability [B(E2)up arrow] between the 0 + ground state and the first 2 + state in even-even nuclei. This compilation together with certain simple relationships noted by other authors can be used to make reasonable predictions of unmeasured B(E2)up arrow values. The quadrupole deformation parameter β 2 immediately follows, because β 2 is proportional to [B(E2)up arrow]/sup 1/2/. 8 refs., 7 figs

  4. Low-spin identical bands in neighboring odd-A and even-even nuclei

    International Nuclear Information System (INIS)

    Baktash, C.; Winchell, D.F.; Garrett, J.D.; Smith, A.

    1993-01-01

    A comprehensive study of odd-A rotational bands in normally deformed rare-earth nuclei indicates that a large number of seniority-one configurations (21 % for odd-Z nuclei) at low spin have moments of inertia nearly identical to that of the seniority-zero configuration of the neighboring even-even nucleus with one less nucleon. It is difficult to reconcile these results with conventional models of nuclear pair correlation, which predict variations of about 15% in the moments of inertia of configurations differing by one unit in seniority. (orig.)

  5. Spin-dependent γ softness or triaxiality in even-even 132-138Nd nuclei

    Science.gov (United States)

    Chai, Qing-Zhen; Wang, Hua-Lei; Yang, Qiong; Liu, Min-Liang

    2015-02-01

    The properties of γ instability in rapidly rotating even-even 132-138Nd isotopes have been investigated using the pairing-deformation self-consistent total-Routhian-surface calculations in a deformation space of (β2, γ, β4). It is found that even-even 134-138Nd nuclei exhibit triaxiality in both ground and excited states, even up to high-spin states. The lightest isotope possesses a well-deformed prolate shape without a γ deformation component. The current numerical results are compared with previous calculations and available observables such as quadrupole deformation β2 and the feature of γ-band levels, showing basically a general agreement with the observed trend of γ correlations (e.g. the pattern of the odd-even energy staggering of the γ band). The existing differences between theory and experiment are analyzed and discussed briefly. Supported by National Natural Science Foundation of China (10805040,11175217), Foundation and Advanced Technology Research Program of Henan Province(132300410125) and S & T Research Key Program of Henan Province Education Department (13A140667)

  6. Low-lying collective quadrupole and octupole strengths in even-even nuclei

    International Nuclear Information System (INIS)

    Raman, S.; Nestor, C.W. Jr.; Kahane, S.; Bhatt, K.H.

    1991-01-01

    The B(E2)↑ values for the first 2 + state of even-even nuclei in the Z≥50 region are compared with the predictions of several theoretical models. Comparative estimates of the overall agreement with the data are provided. Gaps and discrepancies in the data and examples that show interesting features such as shape changes are discussed. The B(E2)↑ values are examined critically to search for the dynamical Pauli effects predicted by the fermion dynamic symmetry model. The empirical B(E2)↑ and B(E3)↑ systematics are employed to obtain a measure of the harmonicity of the quadrupole and octupole vibrations. The fraction of the energy-weighted sum-rule strength exhausted by the sum of all known low-lying 2 + states below 2.3 MeV is found to be surprisingly constant in the 60< A<250 region except near closed shells

  7. Alpha decay and nuclear deformation: the case for favoured alpha transitions of even-even emitters

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, F. [Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Dept. de Ciencias Exatas e Tecnologicas; Rodriguez, O.; Guzman, F. [Instituto Superior de Ciencias y Tecnologia Nucleares (ISCTN), La Habana (Cuba); Goncalves, M. [Instituto de Radioprotecao e Dosimetria IRD/CNEN, Rio de Janeiro, RJ (Brazil); Duarte, S.B.; Tavares, O.A.P. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). E-mail: sbd@cbpf.br

    2000-02-01

    Alpha-decay half-life for ground-state transitions of 174 even-even alpha emitters has been calculated from a simple, Gamow-like model in which the quadrupole deformation of the product nucleus (assumed to have an ellipsoidal shape) is taken into account. The assumption made is that before tunneling through a purely Coulomb potential barrier the two-body system oscillates isotropically, thus giving rise to an equivalent, average polar direction {theta} (referred to the symmetry axis of the ellipsoid) for alpha emission. It is shown that the experimental half-life data are much better reproduced by the present description than in the spherical-shaped approximation for the daughter nucleus. (author)

  8. Alpha decay and nuclear deformation: the case for favoured alpha transitions of even-even emitters

    International Nuclear Information System (INIS)

    Garcia, F.; Goncalves, M.; Duarte, S.B.; Tavares, O.A.P.

    2000-02-01

    Alpha-decay half-life for ground-state transitions of 174 even-even alpha emitters has been calculated from a simple, Gamow-like model in which the quadrupole deformation of the product nucleus (assumed to have an ellipsoidal shape) is taken into account. The assumption made is that before tunneling through a purely Coulomb potential barrier the two-body system oscillates isotropically, thus giving rise to an equivalent, average polar direction θ (referred to the symmetry axis of the ellipsoid) for alpha emission. It is shown that the experimental half-life data are much better reproduced by the present description than in the spherical-shaped approximation for the daughter nucleus. (author)

  9. Damping of isovector giant dipole resonances in hot even-even spherical nuclei

    International Nuclear Information System (INIS)

    Dang, N.D.

    1989-01-01

    An approach based on the finite temperature quasiparticle phonon nuclear model (FT-QPNM) with the couplings to (2p2h) states at finite temperature taken into account is suggested for calculations of the damping of giant multipole resonances in hot even-even spherical nuclei. The strength functions for the isovector giant dipole resonance (IV-GDR) are calculated in 58 Ni and 90 Zr for a range of temperatures up to 3 MeV. The results show that the contribution of the interactions with (2p2h) configurations to the IV-GDR spreading width changes weakly with varying temperature. The IV-GDR centroid energy decreases slightly with increasing temperature. The nonvanishing superfluid pairing gap due to thermal fluctuations is included. (orig.)

  10. Quasi-SU(3) truncation scheme for even-even sd-shell nuclei

    International Nuclear Information System (INIS)

    Vargas, C.E.; Hirsch, J.G.; Draayer, J.P.

    2001-01-01

    The quasi-SU(3) symmetry was uncovered in full pf and sdg shell-model calculations for both even-even and odd-even nuclei. It manifests itself through a dominance of single-particle and quadrupole-quadrupole terms in a Hamiltonian used to describe well-deformed nuclei. A practical consequence of the quasi-SU(3) symmetry is an efficient basis truncation scheme. In [C.E. Vargas et al., Phys. Rev. C 58 (1998) 1488] it is shown that when this type of Hamiltonian is diagonalized in an SU(3) basis, only a few irreducible representations (irreps) of SU(3) are needed to describe the yrast band, the leading S=0 irrep augmented with the leading S=1 irreps in the proton and neutron subspaces. In the present article the quasi-SU(3) truncation scheme is used, in conjunction with a 'realistic but schematic' Hamiltonian that includes the most important multipole terms, to describe the energy spectra and B(E2) transition strengths of 20,22 Ne, 24 Mg and 28 Si. The effect of the size of the Hilbert space on both sets of observables is discussed, as well as the structure of the yrast band and the importance of the various terms in the Hamiltonian. The limitations of the model are explicitly discussed

  11. Quasi-SU(3) truncation scheme for even-even sd-shell nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, C.E. E-mail: cvargas@fis.cinvestav.mx; Hirsch, J.G. E-mail: hirsch@nuclecu.unam.mx; Draayer, J.P. E-mail: draayer@lsu.edu

    2001-07-30

    The quasi-SU(3) symmetry was uncovered in full pf and sdg shell-model calculations for both even-even and odd-even nuclei. It manifests itself through a dominance of single-particle and quadrupole-quadrupole terms in a Hamiltonian used to describe well-deformed nuclei. A practical consequence of the quasi-SU(3) symmetry is an efficient basis truncation scheme. In [C.E. Vargas et al., Phys. Rev. C 58 (1998) 1488] it is shown that when this type of Hamiltonian is diagonalized in an SU(3) basis, only a few irreducible representations (irreps) of SU(3) are needed to describe the yrast band, the leading S=0 irrep augmented with the leading S=1 irreps in the proton and neutron subspaces. In the present article the quasi-SU(3) truncation scheme is used, in conjunction with a 'realistic but schematic' Hamiltonian that includes the most important multipole terms, to describe the energy spectra and B(E2) transition strengths of {sup 20,22}Ne, {sup 24}Mg and {sup 28}Si. The effect of the size of the Hilbert space on both sets of observables is discussed, as well as the structure of the yrast band and the importance of the various terms in the Hamiltonian. The limitations of the model are explicitly discussed.

  12. Comparison of the Porter-Thomas distribution with neutron resonance data of even-even nuclei

    International Nuclear Information System (INIS)

    Camarda, H.S.

    1994-01-01

    The low-energy neutron resonance data of the even-even nuclei 152 Sm, 158 Gd, 162 Dy, 166,168 Er, 182 W, 232 Th, and 236,238 U have been examined in order to test the validity of the Porter-Thomas distribution of the reduced neutron widths---a chi-squared distribution with one degree of freedom (v=1). In an attempt to circumvent the ever-present problems of missed or spurious s wave levels as well as extra p wave levels, a maximum likelihood statistic was employed which used only measured widths greater than some minimum value. A Bayes-theory test applied to the data helped to ensure that p wave contamination of the s wave level population was not significant. The error-weighted value of the number of degrees of freedom for the nine nuclei studied, left-angle v right-angle=0.98±0.10, is consistent with the theoretical expectation of v=1

  13. Systematics of B(E2;01+→21+) values for even-even nuclei

    International Nuclear Information System (INIS)

    Raman, S.; Nestor, C.W. Jr.; Bhatt, K.H.

    1988-01-01

    We have completed a compilation of experimental results for the electric quadrupole transition probability B(E2)up-arrow between the 0 + ground state and the first 2 + state in even-even nuclei. The adopted B(E2)up-arrow values have been employed to test the various systematic, empirical, and theoretical relationships proposed by several authors (Grodzins, Bohr and Mottelson, Wang et al., Ross and Bhaduri, Patnaik et al., Hamamoto, Casten, Moeller and Nix, and Kumar) on a global, local, or regional basis. These systematics offer methods for making reasonable predictions of unmeasured B(E2) values. For nuclei away from closed shells, the SU(3) limit of the intermediate boson approximation implies that the B(E2)up-arrow values are proportional to (e/sub p/N/sub p/+e/sub n/N/sub n/) 2 , where e/sub p /(e/sub n/) is the proton (neutron) effective charge and N/sub p/ (N/sub n/) refers to the number of valence protons (neutrons). This proportionality is consistent with the observed behavior of B(E2)up-arrow vs N/sub p/N/sub n/. For deformed nuclei and the actinides, the B(E2)up-arrow values calculated in a schematic single-particle ''SU(3)'' simulation or large single-j simulation of major shells successfully reproduce not only the empirical variation of the B(E2)up-arrow values but also the observed saturation of these values when plotted against N/sub p/N/sub n/. .AE

  14. Coexistence in even-even nuclei with emphasis on the germanium isotopes

    International Nuclear Information System (INIS)

    Carchidi, M.A.V.

    1985-01-01

    No simple model to date can explain in a self-consistent way the results of direct transfer data and BE2 electromagnetic rates in the germanium isotopes. The simplest models use a two-state interaction for describing the ground state and first excited O + state. In all cases, these models can account for some of the data, but they are in drastic conflict with other experimental measurements. In this thesis, it is shown that a two-state model can consistently account for two-neutron and alpha transfer O + 2 /g.s. cross-section ratio data in the germanium region (ie. zinc, germanium, and selenium), proton occupation number data in the ground states of the even stable zinc, germanium, and selenium isotopes, and BE2 transition rates in isotopes of germanium and zinc. In addition the author can account for most of the one-neutron and two-neutron transfer O + 2 /g.s. and (9/2 + 2 )/(9/2 + 1 ) cross-section ratio data in the odd-mass germanium isotopes. In this generalized two-state model (called Rerg1), the author makes as few assumptions as possible about the nature of the basis states; rather the author allows the experimental data to dictate the properties of the basis-state overlaps. In this sense, the author has learned much about the basis states and has a useful tool for constructing them. The author also shows that the Rerg1 model can quantitatively account for all two-neutron O + 2 /g.s. cross-section ratio data in all even-even nuclei from calcium to uranium

  15. A united phenomenological description of quadrupole excitations in even-even nuclei

    International Nuclear Information System (INIS)

    Lipas, P.O.; Haapakoski, P.; Honkaranta, T.

    1975-05-01

    A phenomenological model is developed for the collective quadrupole properties of all even-even nuclei. Rotational, vibrational, and transitional nuclei are included in the model on an equal footing. A Bohr-type intrinsic Hamiltonian for harmonic quadrupole vibrations about an axially deformed shape is solved exactly. States of good angular momentum are projected out of the intrinsic states, and they are made orthogonal by a Schmidt scheme. The angular-momentum and phonon-number composition of the states is analyzed at various stages; states with K=1 are found spurious. Excitation energies for the ground, β and γ bands are calculated as expectation values of a radically simplified nuclear Hamiltonian in our projected and orthogonalized states. With increasing deformation the calculated energies evolve smoothly from the evenly spaced phonon spectrum to the Bohr-Mottelson rotational-vibrational spectrum according to the scheme of Sheline and Sakai. The basic model contains only two parameters (deformation d and energy scale) to fix the entire quadrupole spectrum of a nucleus. The results are given in the form of graphs suitable for immediate application; numerical results are readily produced by our computer code. The ground bands are fitted comparably to the VMI model, while the β and γ bands are reproduced qualitatively. The nuclei 152 Sm, 152 Gd, and 114 Cd are used as test cases. Quadrupole moments and E2 transition rates are also calculated. Intra-ground-band transition ratios and branching ratios from the β and γ bands are given in terms of the single parameter d. The results are applied to 152 Sm, with fair success. Finally the model to include two more parameters (anisotropy) is extended. The improvement over the basic model is modest in view of added parameters and computational effort. (author)

  16. Collective motions and band structures in A = 60 to 80, even--even nuclei

    International Nuclear Information System (INIS)

    Hamilton, J.H.; Robinson, R.L.; Ramayya, A.V.

    1978-01-01

    Evidence for and the theoretical understanding of the richness of the collective band structures as illustrated by at least seven bands seen in levels of 68 Ge, 74 Se are reviewed. The experimental data on even-even nuclei in the A = 60 to 80 region have now revealed a wide variety of collective bands with different structures. The even parity yrast cascades alone are seen to involve multiple collective structures. In addition to the ground-state bands, strong evidence is presented for both neutron and proton rotation-aligned bands built on the same orbital, (g 9 / 2 ) 2 , in one nucleus. Several other nuclei also show the crossing of RAL bands around the 8 + level in this region. Evidence continues to be strong experimentally and supported theoretically that there is some type of shape transition and shape coexistence occurring now both in the Ge and Se isotopes around N = 40. Negative parity bands with odd and even spins with very collective nature are seen in several nuclei to high spin. These bands seem best understood in the RAL model. Very collective bands with ΔI = 1, extending from 2 + to 9 + are seen with no rotation-alignment. The purity of these bands and their persistence to such high spin establish them as an independent collective mode which is best described as a gamma-type vibration band in a deformed nucleus. In addition to all of the above bands, new bands are seen in 76 Kr and 74 Se. The nature of these bands is not presently known. 56 references

  17. Predicting the optical observables for nucleon scattering on even-even actinides

    Science.gov (United States)

    Martyanov, D. S.; Soukhovitskiĩ, E. Sh.; Capote, R.; Quesada, J. M.; Chiba, S.

    2017-09-01

    The previously derived Lane consistent dispersive coupled-channel optical model for nucleon scattering on 232Th and 238U nuclei is extended to describe scattering on even-even actinides with Z = 90-98. A soft-rotator-model (SRM) description of the low-lying nuclear structure is used, where the SRM Hamiltonian parameters are adjusted to the observed collective levels of the target nucleus. SRM nuclear wave functions (mixed in K quantum number) have been used to calculate the coupling matrix elements of the generalized optical model. The “effective” deformations that define inter-band couplings are derived from the SRM Hamiltonian parameters. Conservation of nuclear volume is enforced by introducing a dynamic monopolar term to the deformed potential, leading to additional couplings between rotational bands. The fitted static deformation parameters are in very good agreement with those derived by Wang and collaborators using the Weizsäcker-Skyrme global mass model (WS4), allowing use of the latter to predict cross sections for nuclei without experimental data. A good description of the scarce “optical” experimental database is achieved. SRM couplings and volume conservation allow a precise calculation of the compound-nucleus formation cross sections, which is significantly different from that calculated with rigid-rotor potentials coupling the ground-state rotational band. The derived parameters can be used to describe both neutron- and proton-induced reactions. Supported by International Atomic Energy Agency, through the IAEA Research Contract 19263, by the Spanish Ministry of Economy and Competitivity under Contracts FPA2014-53290-C2-2-P and FPA2016-77689-C2-1-R.

  18. Validity of single term energy expression for ground state rotational band of even-even nuclei

    International Nuclear Information System (INIS)

    Sharma, S.; Kumar, R.; Gupta, J.B.

    2005-01-01

    Full text: There are large numbers of empirical studies of gs band of even-even nuclei in various mass regions. The Bohr-Mottelson's energy expression is E(I) = AX + BX 2 +CX 3 +... where X = I(I+1). The anharmonic vibrator energy expression is: E(I) = al + bl 2 + cl 3 SF model with energy expression: E(I)= pX + qI + rXI... where the terms represents the rotational, vibrational and R-V interaction energy, respectively. The validity f the various energy expressions with two terms had been tested by Sharma for light, medium and heavy mass regions using R I s. R 4 plots (where, spin I=6, 8, 10, 12), which are parameter independent. It was also noted, that of the goodness of energy expression can be judged with the minimum input of energies (i.e. only 2 parameters) and predictability's of the model p to high spins. Recently, Gupta et. al proposed a single term energy expression (SSTE) which was applied for rare earth region. This proposed power law reflected the unity of rotation - vibration in a different way and was successful in explaining the structure of gs-band. It will be useful for test the single term energy expression for light and heavy mass region. The single term expression for energy of ground state band can be written as: E I =axI b , where the index b and the coefficient a are the constant for the band. The values of b+1 and a 1 are as follows: b 1 =log(R 1 )/log(I/2) and a 1 =E I /I b ... The following results were gained: 1) The sharp variation in the value of index b at given spin will be an indication of the change in the shape of the nucleus; 2) The value of E I /I b is fairly constant with spin below back-bending, which reflects the stability of shape with spin; 3) This proposed power law is successful in explaining the structure of gs-band of nuclei

  19. Calculation of ground state deformation of even-even rare-earth nuclei in sdg interacting boson model

    International Nuclear Information System (INIS)

    Wang Baolin

    1995-01-01

    The analytical calculation of the nuclear ground state deformation of the even-even isotopes in the rare-earth region is given by utilizing the intrinsic states of the sdg interacting boson model. It is compared systematically with the reported theoretical and experimental results. It is shown that the sdg interacting boson model is a reasonable scheme for the description of even-even nuclei deformation

  20. Symmetry structure in neutron deficient xenon nuclei

    International Nuclear Information System (INIS)

    Govil, I. M.

    1998-01-01

    The paper describes the measurements of the lifetimes of the excited states in the ground state band of the Neutron deficient Xe nuclei ( 122,124 Xe) by recoil Distance Method (RDM). The lifetimes of the 2 + state in 122 Xe agrees with the RDM measurements but for 124 Xe it does not agree the RDM measurements but agrees with the earlier Coulomb-excitation experiment. The experimental results are compared with the existing theories to understand the changes in the symmetry structure of the Xe-nuclei as the Neutron number decreases from N=76( 130 Xe) to N=64( 118 Xe)

  1. Symmetry structure in neutron deficient xenon nuclei

    Science.gov (United States)

    Govil, I. M.

    1998-12-01

    The paper describes the measurements of the lifetimes of the excited states in the ground state band of the Neutron deficient Xe nuclei (122,124Xe) by recoil Distance Method (RDM). The lifetimes of the 2+ state in 122Xe agrees with the RDM measurements but for 124Xe it does not agree the RDM measurements but agrees with the earlier Coulomb-excitation experiment. The experimental results are compared with the existing theories to understand the changes in the symmetry structure of the Xe-nuclei as the Neutron number decreases from N=76(130Xe) to N=64(118Xe).

  2. Laser spectroscopy of neutron deficient Sn isotopes

    CERN Multimedia

    We propose to study the ground state properties of neutron-deficient Sn isotopes towards the doubly-magic nucleus $^{100}$Sn. Nuclear spins, changes in the rms charge radii and electromagnetic moments of $^{101-121}$Sn will be measured by laser spectroscopy using the CRIS experimental beam line. These ground-state properties will help to clarify the evolution of nuclear structure properties approaching the $\\textit{N = Z =}$ 50 shell closures. The Sn isotopic chain is currently the frontier for the application of state-of-the-art ab-initio calculations. Our knowledge of the nuclear structure of the Sn isotopes will set a benchmark for the advances of many-body methods, and will provide an important test for modern descriptions of the nuclear force.

  3. Radiochemical studies of neutron deficient actinide isotopes

    International Nuclear Information System (INIS)

    Williams, K.E.

    1978-04-01

    The production of neutron deficient actinide isotopes in heavy ion reactions was studied using alpha, gamma, x-ray, and spontaneous fission detection systems. A new isotope of berkelium, 242 Bk, was produced with a cross-section of approximately 10 μb in reactions of boron on uranium and nitrogen on thorium. It decays by electron capture with a half-life of 7.0 +- 1.3 minutes. The alpha-branching ratio for this isotope is less than 1% and the spontaneous fission ratio is less than 0.03%. Studies of (Heavy Ion, pxn) and (Heavy Ion, αxn) transfer reactions in comparison with (Heavy ion, xn) compound nucleus reactions revealed transfer reaction cross-sections equal to or greater than the compound nucleus yields. The data show that in some cases the yield of an isotope produced via a (H.I.,pxn) or (H.I.,αxn) reaction may be higher than its production via an xn compound nucleus reaction. These results have dire consequences for proponents of the ''Z 1 + Z 2 = Z/sub 1+2/'' philosophy. It is no longer acceptable to assume that (H.I.,pxn) and (H.I.,αxn) product yields are of no consequence when studying compound nucleus reactions. No evidence for spontaneous fission decay of 228 Pu, 230 Pu, 232 Cm, or 238 Cf was observed indicating that strictly empirical extrapolations of spontaneous fission half-life data is inadequate for predictions of half-lives for unknown neutron deficient actinide isotopes

  4. Radiochemical studies of neutron deficient actinide isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Williams, K.E.

    1978-04-01

    The production of neutron deficient actinide isotopes in heavy ion reactions was studied using alpha, gamma, x-ray, and spontaneous fission detection systems. A new isotope of berkelium, /sup 242/Bk, was produced with a cross-section of approximately 10 ..mu..b in reactions of boron on uranium and nitrogen on thorium. It decays by electron capture with a half-life of 7.0 +- 1.3 minutes. The alpha-branching ratio for this isotope is less than 1% and the spontaneous fission ratio is less than 0.03%. Studies of (Heavy Ion, pxn) and (Heavy Ion, ..cap alpha..xn) transfer reactions in comparison with (Heavy ion, xn) compound nucleus reactions revealed transfer reaction cross-sections equal to or greater than the compound nucleus yields. The data show that in some cases the yield of an isotope produced via a (H.I.,pxn) or (H.I.,..cap alpha..xn) reaction may be higher than its production via an xn compound nucleus reaction. These results have dire consequences for proponents of the ''Z/sub 1/ + Z/sub 2/ = Z/sub 1+2/'' philosophy. It is no longer acceptable to assume that (H.I.,pxn) and (H.I.,..cap alpha..xn) product yields are of no consequence when studying compound nucleus reactions. No evidence for spontaneous fission decay of /sup 228/Pu, /sup 230/Pu, /sup 232/Cm, or /sup 238/Cf was observed indicating that strictly empirical extrapolations of spontaneous fission half-life data is inadequate for predictions of half-lives for unknown neutron deficient actinide isotopes.

  5. The first observation of EO transitions from negative parity states in even-even nucleus 160Dy

    International Nuclear Information System (INIS)

    Grigoriev, E.P.

    1988-01-01

    In even-even deformed nuclei up to now EO-transitions were found only between the states of the same spin belonging to Κ π = O + rotational bands. There is no forbidenness for EO-transitions between states belonging to bands with any other quantum number Κ provided both initial and final states have the same J π Κ values. EO-transitions may depopulate odd-parity states. In odd nuclei β-vibrational states are identified by transition with EO-components. Here transitions also proceed between states with the same J π K numbers. Even-even nuclide 160 Dy is the first nucleus where the EO-transitions between odd-parity states have been found

  6. Systematic study of even-even nuclei with Hartree-Fock+BCS method using Skyrme SIII force

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Naoki; Takahara, Satoshi; Onishi, Naoki [Tokyo Univ. (Japan). Coll. of Arts and Sciences

    1997-03-01

    We have applied the Hartree-Fock+BCS method with Skyrme SIII force formulated in a three-dimensional Cartesian-mesh representation to even-even nuclei with 2 {<=} Z {<=} 114. We discuss the results concerning the atomic masses, the quadrupole (m=0, 2) and hexadecapole (m=0, 2, 4) deformations, the skin thicknesses, and the halo radii. We also discuss the energy difference between oblate and prolate solutions and the shape difference between protons and neutrons. (author)

  7. The neutron-proton pairing and the moments of inertia of the rare earth even-even nuclei

    International Nuclear Information System (INIS)

    Calik, A. E.; Deniz, C.; Gerceklioglu, M.

    2009-01-01

    In this study, the possible effect of the neutron-proton pairing interaction in the heavy nuclei has been investigated in the framework of the BCS model by making a simple approximation. This effect has been searched realistically by calculating the moments of inertia of deformed even-even nuclei. Calculations show that the moments of inertia of rare earth nuclei changed dramatically and approached the experimental values.

  8. Pushing the pseudo-SU(3) model towards its limits: Excited bands in even-even Dy isotopes

    International Nuclear Information System (INIS)

    Vargas, Carlos E.; Hirsch, Jorge G.

    2004-01-01

    The energetics of states belonging to normal parity bands in even-even dysprosium isotopes, and their B(E2) transition strengths, are studied using an extended pseudo-SU(3) shell model. States with pseudospin 1 are added to the standard pseudospin 0 space, allowing for a proper description of known excited normal parity bands. A realistic Hamiltonian is employed. Both the success of model and its limitations are discussed

  9. A comparative analysis of alpha-decay half-lives for even-even 178Pb to 234U isotopes

    Science.gov (United States)

    Hosseini, S. S.; Hassanabadi, H.; Zarrinkamar, S.

    2018-02-01

    The feasibility for the alpha decay from the even-even transitions of 178Pb to 234U isotopes has been studied within the Coulomb and proximity potential model (CPPM). The alpha decay half-lives are considered from different theoretical approaches using Semi-empirical formula of Poenaru et al. (SemFIS), the Universal Decay law (UDL) of Qi et al., Akrawy-Dorin formula of Akrawy and Poenaru (ADF), the Scaling law of Brown (SLB) and the Scaling Law of Horoi et al. (SLH). The numerical results obtained by the CPPM and compared with other method as well the experimental data.

  10. A systematic fast-timing study of even-even nuclei in the well deformed A 170-180 region

    Energy Technology Data Exchange (ETDEWEB)

    Jolie, J.; Regis, J.M.; Dannhoff, M.; Gerst, R.B.; Karayonchev, V.; Mueller-Gatermann, C.; Saed-Samii, N.; Stegemann, S.; Blazhev, A. [Institut fuer Kernphysik, Universitaet zu Koeln (Germany); Rudigier, M. [Institut fuer Kernphysik, Universitaet zu Koeln (Germany); Department of Physics, University of Surrey (United Kingdom)

    2016-07-01

    At the Cologne Tandem accelerator we are performing a systematic study of lifetimes in the ground state bands of well deformed even-even nuclei in order to increase the precision of the ns-ps lifetimes and to solve inconsistencies in the literature. The measurements are done using Orange spectrometers, LaBr{sub 3}(Ce) scintillators and Ge detectors. The data are analyzed using the slope and the generalized centroid difference method. The latter allows the measurement of lifetimes down to 5 ps. First results on Yb, Hf and W isotopes are presented.

  11. E2,M1 multipole mixing ratios in even-even nuclei, 58< or =A< or =150

    International Nuclear Information System (INIS)

    Krane, K.S.

    1977-01-01

    A survey is presented of E2,M1 multipole mixing ratios of gamma-ray transitions in even-even nuclei in the mass range 58< or =A< or =150. Angular distribution and correlation data from the literature are analyzed in terms of a consistent choice of the phase relationship between the E2 and M1 matrix elements. A set of recommended values of the mixing ratios is included based on averages of results from various studies. The survey includes data available in the literature up to December 1976

  12. E2,M1 multipole mixing ratios in even--even nuclei, A greater than or equal to 152

    International Nuclear Information System (INIS)

    Krane, K.S.

    1975-01-01

    A survey is presented of E2,M1 mixing ratios of gamma-ray transitions in even-even nuclei with mass numbers A greater than or equal to 152. Angular distribution and correlation data from the literature are analyzed in terms of a consistent choice of the phase relationship between the E2 and M1 matrix elements. The cutoff date for the literature was June 1975. Based on an average of the experimental results from the literature, a recommended value of the E2,M1 mixing ratio for each transition is included

  13. Coulomb Excitation of Neutron Deficient Sn-Isotopes using REX-ISOLDE

    CERN Multimedia

    Di julio, D D; Kownacki, J M; Marechal, F; Andreoiu, C; Siem, S; Perrot, F; Van duppen, P L E; Napiorkowski, P J; Iwanicki, J S

    2002-01-01

    It is proposed to study the evolution of the reduced transition probabilities, B(E2; 0$^{+} \\rightarrow$ 2$^{+}$), for neutron deficient Sn isotopes by Coulomb excitation in inverse kinematics using REX-ISOLDE and the MINIBALL detector array. Measurements of the reduced transition matrix element for the transition between the ground state and the first excited 2$^{+}$ state in light even-even Sn isotopes provide a means to study e.g. core polarization effects in the $^{100}$Sn core. Previous attempts to measure this quantity have been carried out using the decay of isomeric states populated in fusion evaporation reactions. We thus propose to utilize the unique opportunity provided by REX-ISOLDE, after the energy upgrade to 3.1 MeV/u, to use the more model-independent approach of Coulomb excitation to measure this quantity in a number of isotopes in this region.

  14. Two quasi-particle excitations with particle-hole core polarization in even-even single closed shell nuclei

    International Nuclear Information System (INIS)

    Gillet, V.; Giraud, B.; Rho, M.

    1976-01-01

    The energy levels and transition properties of the even-even N=28, 50 isotones and Z=28, 50, 82 isotopes are calculated in the framework of the Tamm-Dancoff and Random Phase Approximation, with an effective central interaction in an extended space consisting of two quasi-particle configurations for the open shell and particle-hole configurations for the closed core. Using the results of the Inverse Gap Equation Method, practically all the necessary input data (single quasi-particle energies, force strength) are extracted from the odd-mass nuclei. The ratios of the force components are kept at fixed values for all studied nuclei and no effective charge is used. An overall excellent agreement is obtained for the energies of the vibrational states. On the other hand, while the transition properties of the 3 - states are always well reproduced, those of the 2 + and 4 + states are often too small by about one order of magnitude [fr

  15. A systematic study of even-even nuclei up to the drip lines within the relativistic mean field framework

    International Nuclear Information System (INIS)

    Hirata, D.; Sumiyoshi, K.; Tanihata, I.; Sugahara, Y.; Tachibana, T.; Toki, H.

    1997-01-01

    We apply the relativistic mean field theory to study the ground state properties of about 2000 even-even nuclei from Z=8 to Z=120 up to the proton and neutron drip lines. The calculations have been done under the axial symmetry assumption and a quadratic constraint method in order to obtain all possible ground state configurations. We do not take into account the pairing correlation in the present study. The calculations are performed with the TMA parameter set. We explore the generaI trend of masses, radii and deformations in the whole region of the nuclear chart. Using the masses obtained from RMF theory, we calculate the r-process abundances and the r-process path. (orig.)

  16. Characteristic 7- and 5- states observed in the (p,t) reactions on even-even rare earth nuclei

    International Nuclear Information System (INIS)

    Ishizaki, Y.; Kubono, S.; Iwasaki, Y.

    1984-01-01

    The (p,t) reactions have been studied for the even-even rare earth nuclei with 40 MeV proton beam from the INS SF cyclotron. A pair of 7 - and 5 - states was observed with large cross sections in each of the nuclei with the neutron number (N) ranging from 86 to 100. For sup(140,142)Nd of N = 80 and 82 the data were obtained at KVI in Groningen, and the data for 152 Sm of N = 90 at MSU. Q value systematics of (p,t) reactions to these states seem to suggest that these are excited by the two neutron pick-up from the neutron core of N = 82. The (p,t) cross sections leading to these states of N from 82 to 96 are nearly constant. (author)

  17. A systematic study of even-even nuclei in the nuclear chart by the relativistic mean field theory

    Energy Technology Data Exchange (ETDEWEB)

    Sumiyoshi, K.; Hirata, D.; Tanihata, I.; Sugahara, Y.; Toki, H. [Institute of Physical and Chemical Research, Wako, Saitama (Japan)

    1997-03-01

    We study systematically the properties of nuclei in the whole mass range up to the drip lines by the relativistic mean field (RMF) theory with deformations as a microscopic framework to provide the data of nuclear structure in the nuclear chart. The RMF theory is a phenomenological many-body framework, in which the self-consistent equations for nucleons and mesons are solved with arbitrary deformation, and has a potential ability to provide all the essential information of nuclear structure such as masses, radii and deformations together with single particle states and wave functions from the effective lagrangian containing nuclear interaction. As a first step toward the whole project, we study the ground state properties of even-even nuclei ranging from Z=8 to Z=120 up to the proton and neutron drip lines in the RMF theory. We adopt the parameter set TMA, which has been determined by the experimental masses and charge radii in a wide mass range, for the effective lagrangian of the RMF theory. We take into account the axially symmetric deformation using the constrained method on the quadrupole moment. We provide the properties of all even-even nuclei with all the possible ground state deformations extracted from the deformation energy curves by the constrained calculations. By studying the calculated ground state properties systematically, we aim to explore the general trend of masses, radii and deformations in the whole region of the nuclear chart. We discuss the agreement with experimental data and the predictions such as magicness and triaxial deformations beyond the experimental frontier. (author)

  18. Study of the odd-${A}$, high-spin isomers in neutron-deficient trans-lead nuclei with ISOLTRAP

    CERN Multimedia

    Herfurth, F; Blaum, K; Beck, D; Kowalska, M; Schwarz, S; Stanja, J; Huyse, M L; Wienholtz, F

    We propose to measure the excitation energy of the $\\frac{13^{+}}{2}$ isomers in the neutron-deficient isotopes $^{193,195,197}$Po with the ISOLTRAP mass spectrometer. The assignment of the low- and high-spin isomers will be made by measuring the energy of the $\\alpha$- particles emitted in the decay of purified beams implanted in a windmill system. Using $\\alpha$-decay information, it is then also possible to determine the excitation energy of the similar isomers in the $\\alpha$-daughter nuclei $^{189,191,193}$Pb, $\\alpha$-parent nuclei $^{197,199,201}$Rn, and $\\alpha$-grand-parent nuclei $^{201,203,205}$Ra. The polonium beams are produced with a UC$_{\\textrm{x}}$ target and using the RILIS.

  19. High-spin states in 214Rn, 216Ra and a study of even-even N = 128 systematics

    International Nuclear Information System (INIS)

    Loennroth, T.; Horn, D.; Baktash, C.; Lister, C.J.; Young, G.R.

    1983-01-01

    High-spin states in 214 Rn and 216 Ra have been studied by means of the reaction 208 Pb( 13 C, α 3n #betta#) 214 Rn and 208 Pb( 13 C, 5n #betta#) 216 Ra at beam energies in the range 75--95 MeV. In-beam spectroscopy techniques, including #betta#-decay excitation functions, α-#betta# coincidences, #betta#-#betta# coincidences, #betta#-ray angular distributions, and pulsed-beam-#betta# timing, were utilized to establish level energies, #betta#-ray multipolarities, J/sup π/ assignments, and isomeric lifetimes. Excited states with spins up to 23h in 214 Rn and roughly-equal30h in 216 Ra were observed. Isomers were found in 214 Rn at 1625 keV (T/sub 1/2/ = 9 ns, J/sup π/ = 8 + ), 1787 keV (22 ns, 10 + ), 3485 keV (95 ns, 16), 4509 keV (230 ns, 20), and 4738 keV (8 ns, 22), and in 216 Ra at 1708 keV (8 ns, 8 + ) and 5868 keV (10 ns, approx.24). B(EL) values were deduced and compared to previously known lead-region electric transition rates. Shell-model calculations were performed and used to make configurational assignments. The absence of major α-decay branching in the isomers is explained and the systematic behavior of N = 128 even-even nuclei is discussed

  20. High-spin states in 214Rn, 216Ra and a study of even-even N = 128 systematics

    International Nuclear Information System (INIS)

    Loennroth, T.; Horn, D.; Baktash, C.; Lister, C.J.; Young, G.R.

    1981-09-01

    High-spin states in 214 Rn and 216 Ra have been studied by means of the reaction 208 Pb( 13 C,α3nγ) 214 Rn and 208 Pb( 13 C,5nγ) 216 Ra at beam energies in the range 75-95 MeV. In-beam spectroscopy techniques, including γ-decay excitation functions, α-γ coincidences, γ-γ coincidences, γ-ray angular distributions and pulsed-beam-γ timing, were utilized to establish level energies, γ-ray multipolarities, JHπ assignments and isomeric lifetimes. Excited states with spins up to 23 h/2π in 214 Rn and 30 h/2π in 216 Ra were established. Isomers are found in 214 Rn at 1625 keV (9 ns, 8 + ), 1787 keV (22 ns, 10 + ), 3485 keV (95 ns, 16 + ), 4509 keV (230 ns, 20 + ) and 4735 keV (8.0 ns, 22 + ) and in 216 Ra at 1710 keV (8 ns, 8 + ) and 5868 keV (10 ns, 24 - ). B(EL) values are derived and compared to previously known lead-region electric transition rates. Shell-model calculations are performed on the basis of which configuration assignment is made. The absence of α-decay branching in the isomers is explained. The systematical behaviour of N = 128 even-even nuclei is discussed. Effective moments of inertia are derived. (author)

  1. Symmetries of Quadrupole-Collective Vibrational Motion in Transitional Even-Even 124−134Xenon Nuclei

    CERN Document Server

    Pietralla, N; Rainovski, G; Ahn, T; Bauer, C; Leske, J; Möller, O; Möller, T

    2010-01-01

    Projectile-Coulomb excitation of Xe isotopes has been performed at ANL using the Gammasphere array for the detection of γ-rays. The one-quadrupole phonon 2+ 1,ms mixed-symmetry state (MSS) has been traced in the stable N=80 isotones down to 134Xe. First, the data on absolute E2 andM1 transition rates quantify the amount of F-spin symmetry in these nuclei and provide a new local measure for the pn-QQ interaction. Second, the evolution of the 2+ 1,ms state has been studied along the sequence of stable even-even 124−134Xe isotopes that are considered to form a shape transition path from vibrational nuclei with vibrational U(5) symmetry near N=82 to γ-softly deformed shapes with almost O(6) symmetry. Third, our data on more than 50 absolute E2 transition rates between off-yrast low-spin states of 124,126Xe enable us to quantitatively test O(6) symmetry in these nuclei. As a result we find that O(6) symmetry is more strongly broken in the A=130 mass region than previously thought. The data will be discussed.

  2. High-spin states in 214Rn, 216Ra and a study of even-even N=128 systematics

    Science.gov (United States)

    Lönnroth, T.; Horn, D.; Baktash, C.; Lister, C. J.; Young, G. R.

    1983-01-01

    High-spin states in 214Rn and 216Ra have been studied by means of the reaction 208Pb(13C, α 3n γ)214Rn and 208Pb(13C, 5n γ)216Ra at beam energies in the range 75-95 MeV. In-beam spectroscopy techniques, including γ-decay excitation functions, α-γ coincidences, γ-γ coincidences, γ-ray angular distributions, and pulsed-beam-γ timing, were utilized to establish level energies, γ-ray multipolarities, Jπ assignments, and isomeric lifetimes. Excited states with spins up to 23ℏ in 214Rn and ~30ℏ in 216Ra were observed. Isomers were found in 214Rn at 1625 keV (T12=9 ns, Jπ=8+), 1787 keV (22 ns, 10+), 3485 keV (95 ns, 16), 4509 keV (230 ns, 20), and 4738 keV (8 ns, 22), and in 216Ra at 1708 keV (8 ns, 8+) and 5868 keV (10 ns, ~24). B(EL) values were deduced and compared to previously known lead-region electric transition rates. Shell-model calculations were performed and used to make configurational assignments. The absence of major α-decay branching in the isomers is explained and the systematic behavior of N=128 even-even nuclei is discussed. NUCLEAR STRUCTURE 208Pb(13C, α 3n γ)214Rn, 208Pb(13C, 5n γ) 216Ra, Elab=75-95 MeV. Measured α-γ coin, γ-γ(t) coin, I(θ), pulsed-beam-γ timing. Deduced level schemes, Jπ, T12, B(EL), multipolarities. Shell model calculations, Ge(Li) and Si detectors, enriched target.

  3. Spectroscopy of very neutron-deficient hafnium and tungsten isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Dracoulis, G D; Fabricius, B; Davidson, P M [Australian National Univ., Canberra, ACT (Australia). Dept. of Nuclear Physics; Macchiavelli, A O; Oliviera, J; Burde, J; Stephens, F; Deleplanque, M A [Lawrence Berkeley Lab., CA (United States)

    1992-08-01

    Level schemes of the very neutron-deficient isotopes {sup 158}Hf and {sup 162}W have been identified, and that for {sup 164}W extended. Alignment of the H{sub 9/2} neutrons is suggested. (author). 12 refs., 7 figs.

  4. Volatility Properties of Polonium

    International Nuclear Information System (INIS)

    Eichler, B.

    2002-06-01

    Thermodynamical constants to describe evaporation processes of polonium are summarized and critically discussed. Additionally, systematic changes of the properties of the chalcogenes are analyzed, empirical correlations are proofed and cyclic processes are balanced. Accordingly, the existing values of entropies for polonium are acceptable. Questionable, however, are those values of enthalpies, which have been deduced from results of the experimental investigations of the vapor pressure temperature dependency, of the melting point, and of the boiling temperatures. Technical difficulties and possible error sources of the measurements resulting from the radioactive decay properties of 210 Po are discussed. Using extrapolative standard enthalpies and entropies as well as their temperature dependency, the equilibrium partial pressure of the monomeric and dimeric polonium above the pure condensed phase and the equilibrium constant of the dimerization reaction in the gas phase are calculated: log p/pa Po (g) = (11.797 ± 0.024) -(9883.4 ± 9.5)/T (for T = 298-600 K); = (10.661 ± 0.057) - (9328.4 ± 4.9)/T (for T = 500-1300 K); log p/pa Po 2 (g) = (13.698 ± 0.049) - (8592.3 ± 19.6)/T (for T = 298-600 K); = (11.424 ± 0.124) - (7584.1 ± 98.1)/T (for T = 500-1300 K); log K (dim) = (-4.895 ± 0.012) + (11071 ± 6)/T. According to these calculations and in contrast to other works, polonium evaporates in the entire temperature range between 298 and 1300 K in the dimeric state. Hence, 'latent heats' of the volatilization processes are clearly larger compared to literature data. Especially in the temperature range of the solid polonium the calculated vapor pressure curve shifts significantly to lower values, whereas the boiling point was almost reproduced by the calculation. The results of the extrapolation for the standard enthalpy of the gaseous monomeric polonium and the dimerization enthalpy ΔH 0 298 Po (g) = 188.9 kJ/mol and ΔH 0 298 (form) Po 2 (g) = 211.5 kJ/mol are

  5. Study of polonium isotopes ground state properties by simultaneous atomic- and nuclear-spectroscopy

    CERN Multimedia

    Koester, U H; Kalaninova, Z; Imai, N

    2007-01-01

    We propose to systematically study the ground state properties of neutron deficient $^{192-200}$Po isotopes by means of in-source laser spectroscopy using the ISOLDE laser ion source coupled with nuclear spectroscopy at the detection setup as successfully done before by this collaboration with neutron deficient lead isotopes. The study of the change in mean square charge radii along the polonium isotope chain will give an insight into shape coexistence above the mid-shell N = 104 and above the closed shell Z = 82. The hyperfine structure of the odd isotopes will also allow determination of the nuclear spin and the magnetic moment of the ground state and of any identifiable isomer state. For this study, a standard UC$_{x}$ target with the ISOLDE RILIS is required for 38 shifts.

  6. Yrast spectroscopy in the neutron-deficient nucleus 169Os

    International Nuclear Information System (INIS)

    Joss, D.T.; Simpson, J.; Appelbe, D.E.; Warner, D.D.; Page, R.D.; King, S.L.; Amzal, N.; Cullen, D.M.; Greenlees, P.T.; Keenan, A.; Baeck, T.; Cederwall, B.; Wyss, R.; Bentley, M.A.; Williams, S.J.; Cocks, J.F.C.; Helariutta, K.; Jones, P.M.; Julin, R.; Juutinen, S.

    2002-01-01

    Excited states in the neutron-deficient isotope 169 Os have been identified for the first time in an experiment using the Jurosphere γ-ray spectrometer in conjunction with the Ritu gas-filled recoil separator. The problems associated with identifying neutron-deficient isotopes produced with low fusion cross sections against a high background of competing channels, including fission, have been overcome by using the recoil-decay tagging technique. The band structures observed in 169 Os are interpreted in the context of the systematics of neighboring nuclei and the predictions of cranked Woods-Saxon calculations. The systematics of the second (i 13/2 ) 2 neutron alignment in this region are discussed

  7. Low energy E0 transitions in odd-mass nuclei of the neutron deficient 180 < A < 200 region

    International Nuclear Information System (INIS)

    Zganjar, E.F.; Kortelahti, M.O.; Wood, J.L.; Papanicolopulos, C.D.

    1987-01-01

    The region of neutron-deficient nuclei near Z = 82 and N = 104 provides the most extensive example of low-energy shape coexistence anywhere on the mass surface. It is shown that E0 and E0 admixed transitions may be used as a fingerprint to identify shape coexistence in odd-mass nuclei. It is also shown that all the known cases of low energy E0 and E0 admixed transitions in odd-mass nuclei occur where equally low-lying O + states occur in neighboring even-even nuclei. A discussion of these and other relevant data as well as suggestions for new studies which may help to clarify and, more importantly, quantify the connection between E0 transitions and shape coexistence are presented. 60 refs., 7 figs., 4 tabs

  8. Shape coexistence in the neutron-deficient mercury isotopes studied through Coulomb excitation

    CERN Document Server

    Bree, Nick

    This thesis describes the analysis and results of a series of Coulomb-excitation experiments on even-even neutron-deficient mercury isotopes aimed at obtaining a more detailed description of shape coexistence. Two experimental campaigns have been undertaken in the Summer of 2007 and 2008. Pure beams of 182,184,186,188Hg were produced and accelerated at the REX-ISOLDE radioactive-beam facility, located at CERN (Geneva, Switzerland). The beams were guided to collide with a stable target to induce Coulomb excitation. The scattered particles were registered by a double-sided silicon strip detector, and the emitted gamma rays by the MINIBALL gamma-ray spectrometer. The motivation to study these mercury isotopes, focused around shape coexistence in atomic nuclei, is addressed in chapter 1, as well as an overview of the knowledge in this region of the nuclear chart. A theoretical description of Coulomb excitation is presented in the second chapter, while the third chapter describes the setup employed for the experim...

  9. Laserspectroscopic studies of collective properties of neutron deficient Ba nuclei

    International Nuclear Information System (INIS)

    Bekk, K.; Andl, A.; Goering, S.; Hanser, A.; Nowicki, G.; Rebel, H.; Schatz, G.

    1979-01-01

    Isotope shifts and hyperfine structure of the BaI resonance-line (lambda=553.6 nm) have been measured by dye laser induced resonance fluorescence on an atomic beam for sup(135m,129g,129m,126) Ba thus extending previous high resolution measurements of neutron deficient Ba nuclides (N - isomers sup(135m) Ba and sup(135m) Ba show a decreased staggering. Conspicuously the isomer shift of the g 7/2 + isomer sup(129m) Ba proves to be negative. The nuclear structure information is discussed in the context of gamma-spectroscopic studies of transitional nuclei with 50 [de

  10. Collinear Resonance Ionization Spectroscopy of Neutron-Deficient Francium Isotopes

    CERN Document Server

    Flanagan, K T; Ruiz, R F Garcia; Budincevic, I; Procter, T J; Fedosseev, V N; Lynch, K M; Cocolios, T E; Marsh, B A; Neyens, G; Strashnov, I; Stroke, H H; Rossel, R E; Heylen, H; Billowes, J; Rothe, S; Bissell, M L; Wendt, K D A; de Groote, R P; De Schepper, S

    2013-01-01

    The magnetic moments and isotope shifts of the neutron-deficient francium isotopes Fr202-205 were measured at ISOLDE-CERN with use of collinear resonance ionization spectroscopy. A production-to-detection efficiency of 1\\% was measured for Fr-202. The background from nonresonant and collisional ionization was maintained below one ion in 10(5) beam particles. Through a comparison of the measured charge radii with predictions from the spherical droplet model, it is concluded that the ground-state wave function remains spherical down to Fr-205, with a departure observed in Fr-203 (N = 116).

  11. Particle-number fluctuations and neutron-proton pairing effects on proton and neutron radii of even-even N Almost-Equal-To Z nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Douici, M.; Allal, N. H.; Fellah, M.; Benhamouda, N.; Oudih, M. R. [Laboratoire de Physique Theorique, Faculte de Physique, USTHB BP 32 El-Alia, 16111 Bab-Ezzouar, Alger (Algeria) and Institut des Sciences et Technologie, Centre Universitaire de Khemis Miliana, Route de Theniet-El-Had, 44225 Khemis-Milia (Algeria); Laboratoire de Physique Theorique, Faculte de Physique, USTHB BP 32 El-Alia, 16111 Bab-Ezzouar, Alger (Algeria) and Centre de Recherche Nucleaire d' Alger, COMENA, BP399 Alger-Gare, Alger (Algeria); Laboratoire de Physique Theorique, Faculte de Physique, USTHB BP 32 El-Alia, 16111 Bab-Ezzouar, Alger (Algeria)

    2012-10-20

    The particle-number fluctuation effect on the root-mean-square (rms) proton and neutron radii of even-even N Almost-Equal-To Z nuclei is studied in the isovector neutron-proton (np) pairing case using an exact particle-number projection method and the Woods-Saxon model.

  12. Deposition potential of polonium

    Energy Technology Data Exchange (ETDEWEB)

    Heal, H. G.

    1948-11-23

    The cathodic deposition potential for polonium in concentrations of 10{sup -13} normal and 8 x 10{sup -13} normal, the former being 100-fold smaller than the smallest concentrations previously studied, has been determined. The value is 0.64 volt on the hydrogen scale. Considering the various ways in which the graphs can reasonably be drawn, we consider the maximum possible error to be of the order of +- 0.03 volt. There is apparently no shift of deposition potential between concentrations of 10{sup -8} and 10{sup -13} normal, indicating that the Nernst equation is not applicable in these circumstances.

  13. Skin Dose Equivalent Measurement from Neutron-Deficient Isotopes

    International Nuclear Information System (INIS)

    Hsu, Hsiao-Hua; Costigan, Steve A.; Romero, Leonard L.; Whicker, Jeffrey J.

    1997-12-01

    Neutron-deficient-isotopes decay via positron emission and/or electron capture often followed by x-ray, gamma-ray, and 0.511 MeV photons from positron annihilation. For cases of significant area and/or personnel contamination with these isotopes, determination of skin dose equivalent (SDE) is required by 10CFR835. For assessment of SDE, we evaluated the MICROSPEC-2(TM) system manufactured by Bubble Technology Industries of Canada which uses three different probes for dose measurement. We used two probes: (1) the X-probe which measures lower energy (4 - 120 keV) photon energy distributions and determines deep dose equivalent, SDE and dose equivalent to eyes, and (2) the B-probe which measures electron (positron) energy distributions, and determines skin dose equivalent. Also, the measured photon and beta spectra can be used to identify radioactive isotopes in the contaminated area. Measurements with several neutron-deficient sources showed that this system provided reasonably accurate SDE rate measurements when compared with calculated benchmark SDE rates with an average percent difference of 40%. Variations were expected because of differences between the assumed geometries used by MlCROSPEC-2 and the calculations when compared to the measurement conditions

  14. Spallation production of neutron deficient radioisotopes in North America

    International Nuclear Information System (INIS)

    Jamriska, D.J.; Peterson, E.J.; Carty, J.

    1997-01-01

    The United States Department of Energy produces a number of neutron deficient radioisotopes by high energy proton induced spallation reactions in accelerators at Los Alamos National Laboratory in New Mexico and Brookhaven National Laboratory in New York. Research isotopes are also recovered from targets irradiated at TRIUMF in British Columbia, Canada. The radioisotopes recovered are distributed for use in nuclear medicine, environmental research, physics research, and industry worldwide. In addition to the main product line of Sr-82 from either Mo or Rb targets, Cu-67 from ZnO targets, and Ge-68 from RbBr targets, these irradiation facilities also produce some unique isotopes in quantities not available from any other source such as Be-10, Al-26, Mg-28, Si-32, El-44, Fe-52, Gd-248, and Hg-194. We will describe the accelerator irradiation facilities at the Los Alamos and Brookhaven National Laboratories. The high level radiochemical processing facilities at Los Alamos and brief chemical processes from Los Alamos and Brookhaven will be described. Chemical separation techniques have been developed to recover the radioisotopes of interest in both high radiochemical purity and yield and at the same time trying to reduce or eliminate the generation of mixed waste. nearly 75 neutron deficient radioisotopes produced in spallation targets have been produced and distributed to researchers around the world since the inception of the program in 1974

  15. Deformation properties of even-even Os, Pt, Hg nuclei and spectroscopic properties of odd Re, Os, Ir, Pt, Au, Hg nuclei from self-consistent calculations

    CERN Document Server

    Desthuilliers-Porquet, M G; Quentin, P; Sauvage-Letessier, J

    1981-01-01

    Static properties of even-even Os, Pt, Hg nuclei have been obtained from HF+BCS calculations. Single-particle wave functions which come from these self-consistent calculations have been used to calculate some spectroscopic properties of odd Re, Os, Ir, Pt, Au, and Hg nuclei, within the rotor-quasiparticle coupling model. The authors' calculations are able to give a good description of most of available experimental data. (12 refs).

  16. Mechanism of fission of neutron-deficient actinoids nuclides

    International Nuclear Information System (INIS)

    Sueki, Keisuke; Nakahara, Hiromichi; Tanase, Masakazu; Nagame, Yuichiro; Shinohara, Nobuo; Tsukada, Kazuaki.

    1996-01-01

    A heavy ion reaction ( 19 F+ 209 Bi) is selected. The reaction produces neutron-deficient 228 U which is compound nucleus with a pair of Rb(z=37) and Cs(Z=55). Energy dissipation problem of nucleus was studied by measuring the isotope distribution of two fissile nuclides. Bismuth metal evaporated on aluminium foil was irradiated by 19 F with the incident energy of 105-128 MeV. We concluded from the results that the excess energy of reaction system obtained with increasing the incident energy is consumed by (1) light Rb much more than Cs and (2) about 60% of energy is given to two fission fragments and the rest 40% to the translational kinetic energy or unknown anomalous γ-ray irradiation. (S.Y.)

  17. Spallation production of neutron deficient radioisotopes in North America

    International Nuclear Information System (INIS)

    Jamriska, D.J.; Peterson, E.J.; Carty, J.

    1997-01-01

    The US Department of Energy produces a number of neutron deficient radioisotopes by high energy proton induced spallation reactions in accelerators at Los Alamos National Laboratory in New Mexico and Brookhaven National Laboratory in New York. Research isotopes are also recovered from targets irradiated at TRIUMF in British Columbia, Canada. The radioisotopes recovered are distributed for use in nuclear medicine, environmental research, physics research, and industry worldwide. In addition to the main product line of Sr-82 from either Mo or Rb targets, Cu-67 from ZnO targets, and Ge-68 and RbBr targets, these irradiation facilities also produce some unique isotopes in quantities not available from any other source such as Al-26, Mg-28, Si-32, Ti-44, Fe-52, Gd-148, and Hg-194. The authors will describe the accelerator irradiation facilities at the Los Alamos and Brookhaven National Laboratories. The high level radiochemical processing facilities at Los Alamos and brief chemical processes will be described

  18. Charge radii of neutron-deficient Ca isotopes

    Science.gov (United States)

    Miller, A. J.; Minamisono, K.; Klose, A.; Everett, N.; Kalman, C.; Powel, R. C.; Watkins, J.; Garand, D.; Sumithrarachchi, C.; Krämer, J.; Maa, B.; Nörtershäuser, W.; Rossi, D. M.; Kujawa, C.; Pineda, S.; Lantis, J.; Liu, Y.; Mantica, P. F.; Pearson, M. R.

    2017-09-01

    Nucleon shell closures are generally associated with a local minimum in mean-square charge radii, 〈r2 〉 , along an isotopic chain. The 〈r2 〉 of 18Ar and 19K isotopes, however, do not show this signature at the N = 20 neutron shell closure. To gain a microscopic understanding of this abnormal behavior, measurements of 〈r2 〉 of neutron-deficient Ca isotopes below N = 20 have been proposed at the BEam COoling and LAser spectroscopy (BECOLA) facility at NSCL/MSU. Preliminary results will be presented and the deduced charge radii will be compared to theoretical calculations and the trends in the nearby isotopic chains. Work supported in part by NSF Grant PHY-15-65546, U.S. DOE Grant DE-NA0002924 and by the Deutsche Forschungsgemeinschaft through Grant SFB 1245.

  19. Mechanism of fission of neutron-deficient actinoids nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Sueki, Keisuke; Nakahara, Hiromichi [Tokyo Metropolitan Univ., Hachioji (Japan). Faculty of Science; Tanase, Masakazu; Nagame, Yuichiro; Shinohara, Nobuo; Tsukada, Kazuaki

    1996-01-01

    A heavy ion reaction ({sup 19}F+{sup 209}Bi) is selected. The reaction produces neutron-deficient {sup 228}U which is compound nucleus with a pair of Rb(z=37) and Cs(Z=55). Energy dissipation problem of nucleus was studied by measuring the isotope distribution of two fissile nuclides. Bismuth metal evaporated on aluminium foil was irradiated by {sup 19}F with the incident energy of 105-128 MeV. We concluded from the results that the excess energy of reaction system obtained with increasing the incident energy is consumed by (1) light Rb much more than Cs and (2) about 60% of energy is given to two fission fragments and the rest 40% to the translational kinetic energy or unknown anomalous {gamma}-ray irradiation. (S.Y.)

  20. AN INVESTIGATION OF THE ENERGY L.EVELS AND MUL TIPOLE MIXING RATIO OF ELECTROMAGNETIC TRANSITIONSIN THE EVEN-EVEN ISOTOPES

    Directory of Open Access Journals (Sweden)

    R. KARAKAYA

    1998-12-01

    Full Text Available In this work some of the electromagnetic interactions of even-even Haf nium isotopes in the 150lt;k:;l90 defoıınation region were studied in a detailed manner. l n this region� us ing the experimental 8(E2/lv11 ınultipole ınixing ratios the deformation parameters �o and the quadrupole moments q0 and q'2 were calculated. The obtained results are in a good agreement ·with the ge neral systematic of the defoıınation region under consideration.

  1. Bacterial mobilization of polonium

    International Nuclear Information System (INIS)

    LaRock, P.; Hyun, J.H.; Burnett, W.C.

    1996-01-01

    Polonium has been observed as the sole α-emitting nuclide in groundwaters of central Florida, in the absence of its radiogenic parents, at levels of 1,000 dpm/1 or more. Because of the chemical similarity of Po to S (both occupy the same column in the periodic table), studies were begun to determine whether bacteria, particularly those species active in sulfur cycling, could account for the selective solubilization and mobilization of Po. Possible sources of Po are the U-rich phosphate rock and phosphogypsum (gypsum), a byproduct in the manufacture of phosphoric acid. This paper reports on a series of experiments involving the interaction of bacteria with this waste gypsum that resulted in the solubilization of Po. Bacteria were isolated from gypsum that were capable of mediating Po release in column experiments of Po. Bacteria were isolated from gypsum that were capable of mediating Po release in column experiments when fed a growth medium. Sulfate-reducing bacteria were particularly effective at mediating Po release provided the sulfide levels did not rise above 10 μM, in which case Po was apparently coprecipitated as a metal sulfide. Conversely, the ability of sulfate-reducing bacteria to effectively remove dissolved Po when sulfide levels are high suggests that these bacteria may be used as an effective bioremediation tool at reducing groundwater Po levels. 22 refs., 10 figs

  2. Consistent evaluations of (n,2n) and (n,np) reaction excitation functions for some even-even isotopes using empirical systematics

    Energy Technology Data Exchange (ETDEWEB)

    Manokhin, Vassily N. [Russian Nuclear Data Center, Institute of Physics and Power Engineering, Obninsk (Russian Federation); Odano, Naoteru; Hasegawa, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-03-01

    An approach for consistent evaluation of (n,2n) and (n,np) reaction excitation functions for some even-even isotopes with the (n,np) reaction thresholds lower than (n,2n) reaction ones is described. For determination of cross sections in the maximum of the (n,2n) and (n,np) reaction excitation functions some empirical systematics developed by Manokhin were used together with trends in dependence of gaps between the (n,2n) and (n,np) thresholds on atomic mass number A. The shapes of the (n,2n) and (n,np) reaction excitation functions were calculated using the normalized functions from the Manokhin's systematics. Excitation functions of (n,2n) and (n,np) reactions were evaluated for several nuclei by using the systematics and it was found that the approach used for the present study gives reasonable results. (author)

  3. Laser spectroscopy of neutron deficient gold and platinum isotopes

    International Nuclear Information System (INIS)

    Savard, G.

    1988-03-01

    A new method for on-line laser spectroscopy of radioactive atoms based on the resonant ionization spectroscopy of laser-desorbed radioactive samples has been devised. An experimental setup has been installed on-line at the ISOCELE mass separator in Orsay (France) and experiments have been performed on the region of transitional nuclei around Z=79. Isotopic shift measurements on four new isotopes 194 Au, 196 Au, 198 Au, 199 Au have been performed on gold and results on the neutron deficient isotopes down to 186 Au have been obtained confirming the nuclear ground-state shape transition from oblate to prolate between 187 Au and 186 Au. The first isotopic shift measurements on radioactive platinum isotopes have been obtained on 186 Pt, 188 Pt, 189 Pt. Indications of a shape transition have been observed between 186 Pt and 188 Pt. The extracted experimental changes in mean square charge radii δ 2 > A,A' along isotopic chains are compared to self-consistent Hartree-Fock plus BCS calculations

  4. The environmental behaviour of polonium

    International Nuclear Information System (INIS)

    Phaneuf, M.; Twining, J.; )

    2013-01-01

    In view of the importance of 210 Po as a dose contributor, the IAEA is completing a second specific Technical Reports Series document, entitled 'The Environmental Behaviour of Polonium'. This document covers the behaviour of polonium in terrestrial, freshwater and marine environments, and provides up-to-date information on key transfer processes, concepts and models that have been found to be important in radiological assessments for both humans and non-human biota. Additionally, applications of Po isotopes to environmental issues are discussed in order to alert readers to studies that use Po isotopes as tracers of environmental processes

  5. Radon risk: the polonium effects

    International Nuclear Information System (INIS)

    Pradel, J.

    2003-01-01

    The atoms of radon present in the earth's crust give after disintegration atoms of polonium 210 and lead 210 having a strong toxicity by ingestion ( superior of a factor 2 to 10 comparatively to plutonium 239). We have to remember that polonium and lead 210 are present everywhere in very important quantities relatively to values quoted for ground pollution. This must reassure us for the risks run from the nuclear facilities for which important efforts are made in matter of radiation protection. (N.C.)

  6. Reduced electric-octupole transition probabilities, B(E3;O1+ → 31-), for even-even nuclides throughout the periodic table

    International Nuclear Information System (INIS)

    Spear, R.H.

    1988-11-01

    Adopted values for the excitation energy, E x( 3 1 - ), of the first 3 - state of the even-even nuclei are tabulated. Values of the reduced electric-octupole transition probability, B(E3;O 1 + → 3 1 - ), from the ground state to this state, as determined from Coulomb excitation, lifetime measurements, inelastic electron scattering, deformation parameters β 3 obtained from angular distributions of inelastically scattered nucleons and light ions, and other miscellaneous procedures are listed in separate Tables. Adopted values for B(E3; O 1 + → 3 1 - ) are presented in Table VII, together with the E3 transition strengths, in Weisskopf units, and the product E x( 3 1 - ) x B(E3; O 1 + → 3 1 - - ) expressed as a percentage of the energy-weighted E3 sum-rule strength. An evaluation is made of the reliability of B(E3; O 1 + → 3 1 - ) values deduced from deformation parameters β 3 . The literature has been covered to March 1988

  7. Study of the deexcitation by monopole pair emission from the first J=0+ states in some even-even nuclei of the 2s-1d shell

    International Nuclear Information System (INIS)

    Souw, Kenghok.

    1975-01-01

    A new high efficiency plastic scintillation pair spectrometer was used to measure the E0 branching ratio GAMMAsub(π)/GAMMA(tot) (GAMMAsub(π)=pair emission partial width, GAMMA(tot)=total width) of the transition from the first excited Jsup(π)=0 + state to the Jsup(π)=0 + ground state in some even-even nuclei of the 2s-1d shell. Experiments were performed on 18 O, 26 Mg, 30 Si, 32 S, 34 S and 38 Ar nuclei. The method consisted in detecting the electron and positron of the pair in coincidence in two telescopes. A surface barrier counter placed downstream the target, working in coincidence with the spectrometer, allowed the relevant pair-decays to be selected and the feeding yield to be determined from direct spectra. The branching ratios were such directly determined. These ratios combined with the values available for the lifetimes of these states give the monopole matrix elements Msub(π). The single particle strength of these decays passes through a minimum in the middle of the shell ( 30 Si) and reaches a maximum around the closed shells ( 18 O, and 48 Ca) [fr

  8. The salient features of charge density distributions of medium and heavy even-even nuclei determined from a systematic analysis of elastic electron scattering from factors

    International Nuclear Information System (INIS)

    Friedrich, J.; Voegler, N.

    1982-01-01

    All available information on charge distributions of even-even nuclei is analysed systematically. For medium and heavy nuclei five general features of p(r) are investigated: (i) The extension for which we discuss several different definitions. The measured extension together with experimental binding energies allows a determination of nuclear compressibility within the framework of the droplet model, the resulting value being K = 165 +- 10 MeV. (ii) The surface thickness. Here too, several definitions are discussed. A close relationship between the surface thickness and binding energies is demonstrated. (iii) The average slope in the inner part of the nucleus. A method is formulated to separate this slope from the oscillations observed. All nuclei show a positive slope of comparable size. (iv) The oscillations on p(r). They are related to an abrupt breakdown in the form factor around q = 2.25 fm -1 . This effect seems to be closely related to the fact that p(r) is built up out of single particles, details however being unimportant. (v) The high-q components of the form factor are indicative for a scattering mechanism involving pairs of nucleons. (orig.)

  9. The Determination of Neutron-Induced Reaction Cross Section Data on Even-Even, Magic- Number Nuclide Chromium 52 Using EXIFON Code

    International Nuclear Information System (INIS)

    Jonah, S.A.

    2013-01-01

    The EXIFON code version 2.0 is a calculational tool, which is based on both many-body theory and random matrix physics. In this work, it has been used to calculate neutron induced reaction cross section data from 0 to 20 MeV on an even-even, magic number nuclide 52 Cr with neutron number, N=28. Specifically, the (n,p), (n,α) and (n,2n) reaction cross section data were calculated as functions of incident energy of neutrons. Data obtained from the experimental data in the IAEA, EXFOR data Library and recommended data libraries around the globe, JENDL, ENDF and JEFF were used to validate the calculated data. The data indicate that the calculated data without shell corrections are in good agreement with experimental data as well as the recommended data from the evaluated data libraries. The calculated results could provide useful insight into the choice of some input parameters near closed shells using the EXIFON code.

  10. The B(E2;4^+1->2^+1) / B(E2;2^+1->0^+1) Ratio in Even-Even Nuclei

    Science.gov (United States)

    Loelius, C.; Sharon, Y. Y.; Zamick, L.; G"Urdal, G.

    2009-10-01

    We considered 207 even-even nuclei throughout the chart of nuclides for which the NNDC Tables had data on the energies and lifetimes of the 2^+1 and 4^+1 states. Using these data we calculated for each nucleus the electric quadrupole transition strengths B(E2;4^+1->2^+1) and B(E2;2^+1->0^+1), as well as their ratio. The internal conversion coefficients were obtained by using the NNDC HSICC calculator. For each nucleus we plotted the B(E2) ratio against A, N, and Z. We found that for close to 90% of the nuclei considered the ratio had values between 0.5 and 2.5. Most of the outliers had magic numbers of protons or neutrons. Our ratio results were compared with the theoretical predictions for this ratio by different models--10/7 in the rotational model and 2 in the simplest vibrational model. In the rotational regions (for 150 220) the ratios were indeed close to 10/7. For the few nuclei thought to be vibrational the ratios were usually less than 2. Otherwise, we got a wide scatter of ratio values. Hence other models, including the NpNn scheme, must be considered in interpreting these results.

  11. Fermionic symmetries: Extension of the two to one relationship between the spectra of even-even and neighboring odd mass nuclei

    International Nuclear Information System (INIS)

    Zamick, L.; Devi, Y.D.

    1999-01-01

    In the single j shell there is a two to one relationship between the spectra of certain even-even and neighboring odd mass nuclei; e.g., the calculated energy levels of J=0 + states in 44 Ti are at twice the energies of corresponding levels in 43 Ti( 43 Sc) with J=j=7/2. Here an approximate extension of the relationship is made by adopting a truncated seniority scheme; i.e., for 46 Ti and 45 Sc we get the relationship if we do not allow the seniority v=4 states to mix with the v=0 and v=2 states. Better than that, we get very close to the two to one relationship if seniority v=4 states are admixed perturbatively. In addition, it is shown that for the J=0 T=3 state in 46 Ti and for the J=j T=5/2 state in 45 Sc (i.e., the states of higher isospin) there are no admixtures in which the neutrons have seniority 4. copyright 1999 The American Physical Society

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

    International Nuclear Information System (INIS)

    Koopman, R.P.

    1977-01-01

    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 56 Fe, 62 Ni, 64 Zn, 108 Pd, 110 Cd, 114 Cd, 116 Cd, 116 Sn, 120 Sn, and 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 + levels. Consequently, the strength of the 2 + → 0 + 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 + → 0 + 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

  13. Calculation of multidimensional potential energy surfaces for even-even transuranium nuclei: systematic investigation of the triaxiality effect on the fission barrier

    Science.gov (United States)

    Chai, Qing-Zhen; Zhao, Wei-Juan; Liu, Min-Liang; Wang, Hua-Lei

    2018-05-01

    Static fission barriers for 95 even-even transuranium nuclei with charge number Z = 94–118 have been systematically investigated by means of pairing self-consistent Woods-Saxon-Strutinsky calculations using the potential energy surface approach in multidimensional (β 2, γ, β 4) deformation space. Taking the heavier 252Cf nucleus (with the available fission barrier from experiment) as an example, the formation of the fission barrier and the influence of macroscopic, shell and pairing correction energies on it are analyzed. The results of the present calculated β 2 values and barrier heights are compared with previous calculations and available experiments. The role of triaxiality in the region of the first saddle is discussed. It is found that the second fission barrier is also considerably affected by the triaxial deformation degree of freedom in some nuclei (e.g., the Z=112–118 isotopes). Based on the potential energy curves, general trends of the evolution of the fission barrier heights and widths as a function of the nucleon numbers are investigated. In addition, the effects of Woods-Saxon potential parameter modifications (e.g., the strength of the spin-orbit coupling and the nuclear surface diffuseness) on the fission barrier are briefly discussed. Supported by National Natural Science Foundation of China (11675148, 11505157), the Project of Youth Backbone Teachers of Colleges and Universities of Henan Province (2017GGJS008), the Foundation and Advanced Technology Research Program of Henan Province (162300410222), the Outstanding Young Talent Research Fund of Zhengzhou University (1521317002) and the Physics Research and Development Program of Zhengzhou University (32410017)

  14. Study of Neutron-Deficient $^{202-205}$Fr Isotopes with Collinear Resonance Ionization Spectroscopy

    CERN Document Server

    De Schepper, Stijn; Cocolios, Thomas; Budincevic, Ivan

    The scope of this master’s thesis is the study of neutron-deficient $^{202−205}$Fr isotopes. These isotopes are inside the neutron-deficient lead region, a region that has shown evidence of shape coexistence. For this thesis, this discussion is limited to the phenomenon where a low lying excited state has a different shape than the ground state. Shape coexistence is caused by intruder states. These are single-particle Shell Model states that are perturbed in energy due to the interaction with a deformed core. In the neutron-deficient lead region the main proton intruder orbit is the 3s$_{1/2}$orbit. When going towards more neutron-deficient isotopes, deformation increases. The $\\pi3s_{1/2}$orbit will rise in energy and will eventually become the ground state in odd- A bismuth (Z=83) isotopes. It is also observed in odd-A astatine (Z=85) isotopes, already in less neutron-deficient nuclei. The same phenomenon is expected to be present francium (Z=87) isotopes already at $^{199}$Fr. Although it is currently ...

  15. Sulfur, selenium, tellurium and polonium

    International Nuclear Information System (INIS)

    Berry, F.J.

    1987-01-01

    This chapter on the coordination compounds of sulfur, selenium, tellurium and polonium starts with an introduction to the bonding, valence and geometry of the elements. Complexes of the group VIB elements are discussed with particular reference to the halo and pseudohalide complexes, oxo acid complexes, oxygen and nitrogen donor complexes and sulfur and selenium donor complexes. There is a section on the biological properties of the complexes discussed. (UK)

  16. Study of asymmetric fission yield behavior from neutron-deficient Hg isotope

    International Nuclear Information System (INIS)

    Perkasa, Y. S.; Waris, A.; Kurniadi, R.; Su'ud, Z.

    2014-01-01

    A study of asymmetric fission yield behavior from a neutron-deficient Hg isotope has been conducted. The fission yield calculation of the neutron-deficient Hg isotope using Brownian Metropolis shape had showed unusual result at decreasing energy. In this paper, this interesting feature will be validated by using nine degree of scission shapes parameterization from Brosa model that had been implemented in TALYS nuclear reaction code. This validation is intended to show agreement between both model and the experiment result. The expected result from these models considered to be different due to dynamical properties that implemented in both models

  17. Polonium: 110th anniversary of its discovery

    International Nuclear Information System (INIS)

    Mould, R. F.

    2008-01-01

    It is appropriate that the 110 Th anniversary of the discovery of polonium by Marie and Pierre Curie is commemorated in a Polish journal since this element was named for Poland and was also the element discovered by the Curies before they discovered radium. Polonium's discovery and characteristics are described. Polonium has never been used in medicine, and was largely forgotten apart from a few minor industrial uses, and as a trigger for a nuclear weapon, until the murder in November 2006 in London using 210 Polonium, of the ex-KGB officer Alexander Litvinenko. Polonium had previously been linked, without any definite proof, with the deaths of a few scientists who had worked with the element, including Irene and Frederick Joliet-Curie. This review ends with possible evidence for such links. (authors)

  18. Shape coexistence in the neutron-deficient Pt isotopes in the configuration-mixed IBM

    International Nuclear Information System (INIS)

    Vargas, Carlos E.; Campuzano, Cuauhtemoc; Morales, Irving O.; Frank, Alejandro; Van Isacker, Piet

    2008-01-01

    The matrix-coherent state approach in the IBM with configuration mixing is used to describe the geometry of neutron-deficient Pt isotopes. Employing a parameter set for all isotopes determined previously, it is found that the lowest minimum goes from spherical to oblate and finally acquires a prolate shape when approaching the mid-shell Pt isotopes

  19. Internal dosimetry of polonium-210

    International Nuclear Information System (INIS)

    Pucelj, B.

    2007-01-01

    On November 1, 2006, former Russian agent Alexander Litvinenko suddenly fell ill and was hospitalised. He died three weeks later, becoming the first known victim of lethal polonium-210 induced acute radiation syndrome. Po-210 is an alpha emitter and is not a radiological hazard as long as it remains outside the body. If taken into the body, much of Po-210 is subsequently excreted, mostly through faeces and some through urine and other pathways. After uptake by the blood, Po-210 is widely distributed through soft body tissues including bone marrow. The internal dose from polonium in the body gives rise to an increase in lifetime cancer risk. Very high radiation doses can cause severe damage to body tissues and organs and in the extreme can be fatal. The hazard function model was used to estimate the lethal levels of intake of Po-210. In case of Litvinenko the destruction of bone marrow and resulting failure of the immune system was most probably the main cause of death, likely to be compounded by damage caused by higher doses to other organs, including kidneys and liver. It was estimated that the ingestion of several hundreds MBq or just about a microgram of Po-210 can be lethal. (author)

  20. Lead-210 and polonium-210 in grass

    Energy Technology Data Exchange (ETDEWEB)

    Hill, C R

    1960-07-16

    It appears that an important contribution to the observed ..cap alpha..-activity of grass may be provided by a process of natural fall-out in which lead-210 resulting from decay of atmospheric radon, together with a fraction of the equilibrium amount of its descendant polonium-210 are deposited by rainfall directly on to foliage. Metabolic uptake of part of this activity by sheep is indicated by the presence in the kidney of polonium-210. 6 references, 1 figure, 2 tables.

  1. Nuclear charge radii and nuclear moments of neutron deficient Ba isotopes from high resolution laser spectroscopy

    International Nuclear Information System (INIS)

    Nowicki, G.; Bekk, K.; Goering, S.; Hanser, A.; Rebel, H.; Schatz, G.

    1978-07-01

    Isotope shifts and hyperfine structure of the BaI 6s 2 1 S 0 -6s6p 1 P 1 transitions (lambda = 553.6 nm) in neutron deficient Ba nuclides (N 131 Ba, 128 Ba, in addition to remeasurements of all stable Ba nuclides. The extracted values of delta 2 >, the observed odd-even staggering and the nuclear moments are discussed in the light of other theoretical and experimental nuclear structure studies of the region 50 [de

  2. Shape coexistence in the neutron-deficient Pt isotopes in a configuration mixing IBM

    International Nuclear Information System (INIS)

    Morales, Irving O.; Vargas, Carlos E.; Frank, Alejandro

    2004-01-01

    The recently proposed matrix-coherent state approach for configuration mixing IBM is used to describe the evolving geometry of the neutron deficient Pt isotopes. It is found that the Potential Energy Surface (PES) of the Platinum isotopes evolves, when the number of neutrons decreases, from spherical to oblate and then to prolate shapes, in agreement with experimental measurements. Oblate-Prolate shape coexistence is observed in 194,192Pt isotopes

  3. Thermochromatography study of volatile polonium species in various gas atmospheres

    CERN Document Server

    Maugeri, Emilio Andrea; Eichler, Robert; Piguet,David; Mendonça, Tania Melo; Stora, Thierry; Schumann, Dorothea

    2014-01-01

    Phenomena related to the volatilization of polonium and its compounds are critical issues for the safety assessment of the innovative lead–bismuth cooled type of nuclear reactor or accelerator driven systems. The formation and volatilization of different species of polonium and their interaction with fused silica was studied by thermochromatography using carrier gases with varied redox potential. The obtained results show that under inert and reducing conditions in the absence of moisture, elemental polonium is formed. Polonium compounds more volatile than elemental polonium can be formed if traces of moisture are present in both inert and reducing carrier gas. The use of dried oxygen as carrier gas leads to the formation of polonium oxides, which are less volatile than elemental polonium. It was also found that the volatility of polonium oxides increases with increasing oxidation state. In the presence of moisture in an oxidizing carrier gas, species are formed that are more volatile than the oxides and le...

  4. Polonium-210 budget in cigarettes

    International Nuclear Information System (INIS)

    Khater, A.E.M.

    2004-01-01

    Due to the relatively high activity concentrations of 210 Po and 210 Pb that are found in tobacco and its products, cigarette smoking highly increases the internal intake of both radionuclides and their concentrations in the lung tissues. That might contribute significantly to an increase in the internal radiation dose and in the number of instances of lung cancer observed among smokers. Samples of most frequently smoked fine and popular brands of cigarettes were collected from those available on the Egyptian market. 210 Po activity concentrations were measured by alpha spectrometry, using surface barrier detectors, following the radiochemical separation of polonium. Samples of fresh tobacco, wrapping paper, fresh filters, ash and post-smoking filters were spiked with 208 Po for chemical recovery calculation. The samples were dissolved using mineral acids (HNO 3 , HCl and HF). Polonium was spontaneously plated-out on stainless steel disks from diluted HCl solution. The 210 Po activity concentration in smoke was estimated on the basis of its activity in fresh tobacco and wrapping paper, fresh filter, ash and post-smoking filters. The percentages of 210 Po activity concentrations that were recovered from the cigarette tobacco to ash, post-smoking filters, and smokes were assessed. The results of this work indicate that the average (range) activity concentration of 210 Po in cigarette tobacco was 16.6 (9.7-22.5) mBq/cigarette. The average percentages of 210 Po content in fresh tobacco plus wrapping paper that were recovered by post-smoking filters, ash and smoke were 4.6, 20.7 and 74.7, respectively. Cigarette smokers, who are smoking one pack (20 cigarettes) per day, are inhaling on average 123 mBq/d of 210 Po and 210 Pb each. The annual effective doses were calculated on the basis of 210 Po and 210 Pb intake with the cigarette smoke. The mean values of the annual effective dose for smokers (one pack per day) were estimated to be 193 and 251 μSv from 210 Po and 210

  5. Measurements of competing structures in neutron-deficient Pb isotopes by employing Coulomb excitation

    CERN Multimedia

    Bastin, B; Kruecken, R; Larsen, A; Rahkila, P J; Srebrny, J; Clement, E; Wadsworth, R; Syed naeemul, H; Peura, P J; Siem, S; Hadynska-klek, K; Habs, D; Napiorkowski, P J; Diriken, J V J; Iwanicki, J S

    Coulomb excitation measurements to study the shape coexistence and quadrupole collectivity of the low-lying levels in neutron-deficient Pb nuclei are proposed. Even-mass $^{188−192}$Pb nuclei will be post-accelerated at REX-ISOLDE in order to measure transition probabilities and quadrupole moments for the first excited states. In combination with results obtained in lifetime measurements, this will allow the sign of the quadrupole deformation parameter to be extracted for the first time for 2$^{+}$ states in the even-mass $^{188−192}$Pb nuclei.

  6. Study of oblate nuclear shapes and shape coexistence in neutron-deficient rare earth isotopes

    CERN Multimedia

    Guttormsen, M S; Reiter, P; Larsen, A; Korten, W; Clement, E; Siem, S; Renstrom, T; Buerger, A; Jenkins, D G

    We propose to investigate nuclear shapes and shape coexistence in neutron-deficient rare earth nuclei below the N=82 shell closure at the ISOLDE facility by employing Coulomb excitation of Nd, Sm, Gd, and Dy beams from the REX accelerator and the Miniball experiment. Nuclear shapes are expected to change rapidly in this region of the nuclear chart. The measurement of electric quadrupole moments of excited states and the transition rates between them serves as a stringent test of theoretical models and effective nucleon-nucleon interactions.

  7. Further studies of neutron-deficient Sn-isotopes using REX-ISOLDE

    CERN Multimedia

    Larsen, A; Syed naeemul, H; Siem, S

    2007-01-01

    Encouraged by the committee to submit the latter part of our latest addendum to experiment IS418 under a new heading this proposal focuses on the second physics case mentioned there. We propose to use Coulomb excitation of odd mass neutron-deficient Sn isotopes to study some dominantly "one quasi-particle" states in these nuclei. Due to spin selection rules these states are difficult to populate following either $\\beta$-decay or in a cascade after a fusion-evaporation reactions, whereas the excitation from the ground-state is of E2 character for some of the most interesting cases.

  8. Shape transition and coexistence in neutron-deficient rare earth isotopes

    CERN Multimedia

    We propose to study spectroscopic quadrupole moments of excited states and electromagnetic transition rates between them in the neutron-deficient rare earth nuclei $^{140}$Sm and $^{142}$Gd using projectile Coulomb excitation at energies of 4.7 MeV per nucleon. The rare earth nuclei below the N=82 shell closure form one of the few regions of the nuclear chart where oblate shapes are expected to occur near the ground state. Nuclear shapes are expected to change rapidly in this region, with coexistence of oblate and prolate shapes in some nuclei. The measurement of electromagnetic matrix elements represents therefore a particularly sensitive test of theoretical nuclear structure models.

  9. Projected shell model study of yrast states of neutron-deficient odd-mass Pr nuclei

    International Nuclear Information System (INIS)

    Ibanez-Sandoval, A.; Ortiz, M. E.; Velazquez, V.; Galindo-Uribarri, A.; Hess, P. O.; Sun, Y.

    2011-01-01

    A wide variety of modern instruments allow us to study neutron-deficient nuclei in the A=130 mass region. Highly deformed nuclei have been found in this region, providing opportunities to study the deformed rotational bands. The description of the 125,127,129,131,133 Pr isotopes with the projected shell model is presented in this paper. Good agreement between theory and experiment is obtained and some characteristics are discussed, including the dynamic moment of inertia J (2) , kinetic moment of inertia J (1) , the crossing of rotational bands, and backbending effects.

  10. Fluorescent atom coincidence spectroscopy of extremely neutron-deficient barium isotopes

    International Nuclear Information System (INIS)

    Wells, S.A.; Evans, D.E.; Griffith, J.A.R.; Eastham, D.A.; Groves, J.; Smith, J.R.H.; Tolfree, D.W.L.; Warner, D.D.; Billowes, J.; Grant, I.S.; Walker, P.M.

    1988-01-01

    Fluorescent atom coincidence spectroscopy (FACS) has been used to measure the nuclear mean square radii and moments of the extremely neutron-deficient isotopes 120-124 Ba. At N=65 an abrupt change in nuclear mean square charge radii is observed which can be understood in terms of the occupation of the spin-orbit partner g 7/2 5/2[413] neutron and g 9/2 9/2[404] proton orbitals and the consequent enhancement of the n-p interaction. (orig.)

  11. Spectroscopy of light neutron deficient nuclei: 31Ar and 27S decays

    International Nuclear Information System (INIS)

    Borrel, V.

    1991-01-01

    Light neutron-deficient nuclei exhibit several interesting decay modes. In some cases, beta-delayed alpha emission becomes possible, and beta-delayed three-proton emission can be allowed. The energy spectra of the emitted protons should give informations on the position of the isobaric analog state and on its deexcitation modes. Experimental results obtained at GANIL with the LISE spectrometer on the decay of the isotopes 31 Ar and 27 S are presented. These data are discussed and compared with the predicted isobaric analog state excitation energies and with shell-model calculations. (G.P.) 13 refs.; 7 figs.; 1 tab

  12. β Decay in the Region of Neutron-deficient {sup 69,70,71}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, A.M., E-mail: ARogers@lbl.gov [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA, 94720 (United States); Giovinazzo, J. [Centre d' Etudes Nucléaires de Bordeaux-Gradignan, Université Bordeaux 1, UMR 5797 CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175, Gardignan Cedex (France); Lister, C.J. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Blank, B.; Canchel, G. [Centre d' Etudes Nucléaires de Bordeaux-Gradignan, Université Bordeaux 1, UMR 5797 CNRS/IN2P3, Chemin du Solarium, BP 120, F-33175, Gardignan Cedex (France); Clark, J.A. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); France, G. de; Grévy, S. [GANIL CEA/DSM-CNRS/IN2P3, Boulevard Henri Becquerel, BP55027, 14076 CEAN Cedex 5 (France); Gros, S.; McCutchan, E.A. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Oliveira Santos, F. de [GANIL CEA/DSM-CNRS/IN2P3, Boulevard Henri Becquerel, BP55027, 14076 CEAN Cedex 5 (France); Savard, G.; Seweryniak, D. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Stefan, I.; Thomas, J.-C. [GANIL CEA/DSM-CNRS/IN2P3, Boulevard Henri Becquerel, BP55027, 14076 CEAN Cedex 5 (France)

    2014-06-15

    Decay spectroscopy was performed for neutron-deficient nuclei ranging from zinc to krypton with isospin −3/2 ≤T{sub z}≤0. Measurements of correlated β-delayed protons allowed us to determine the isobaric analog states fed from the decay of {sup 65}Se and {sup 69}Kr, constraining the spin of the {sup 69}Kr ground state. Preliminary results regarding the half lives for the T{sub z}=−1 systems, relevant to the rapid proton capture (rp) process, are discussed.

  13. New neutron-deficient isotopes of barium and rare-earth elements

    CERN Document Server

    Bogdanov, D D; Karnaukhov, V A; Petrov, L A; Plochocki, A; Subbotin, V G; Voboril, J

    1976-01-01

    The authors present an investigation of the short-lived neutron- deficient isotopes of barium and rare-earth elements. By using the BEMS-2 isotope separator on a heavy ion beam, 19 new isotopes were produced with mass numbers ranging from 117 to 138. Five of these (/sup 117/Ba, /sup 129,131/Nd and /sup 133,135/Sm) turned out to be delayed proton emitters. The beta -decay probabilities for the new isotopes have been analyzed in terms of the beta -strength function. An analysis of the proton spectrum shape has been performed using the statistical model for delayed proton emission.

  14. First observation of excited structures in neutron-deficient 179Hg : evidence for multiple shape coexistence

    International Nuclear Information System (INIS)

    Kondev, F.G.; Carpenter, M.P.; Janssens, R.V.F.; Lister, C.J.; Abu Saleem, K.; Ahmad, I.; Amro, H.; Caggiano, J.; Davids, C.N.; Heinz, A.; Herskind, B.; Khoo, T.L.; Lauristen, T.; Ma, W.C.; Ressler, J.J.; Reviol, W.; Riedinger, L.L.; Sarantites, D.G.; Seweryniak, D.; Siem, S.; Sonzongni, A.A.; Varmette, P.G.; Wiedenhoever, I.

    2002-01-01

    Excited structures in the neutron-deficient nucleus 179 Hg have been established for the first time using the Gammasphere spectrometer in conjunction with the fragment mass analyzer. Competing states originating from three different minima associated with nearly spherical, oblate, and prolate deformations were found. This result can be contrasted with the situation in heavier odd-mass Hg isotopes where only two minima (oblate and prolate) have been seen. The implications of these three shapes at low spin and excitation energy are discussed in the general context of shape coexistence in this mass region.

  15. Polonium-210 as a poison

    International Nuclear Information System (INIS)

    Harrison, John; Leggett, Rich; Lloyd, David; Phipps, Alan; Scott, Bobby

    2007-01-01

    The death of Alexander Litvinenko on 23 November 2006 has brought into focus scientific judgements concerning the radiotoxicity of polonium-210 ( 210 Po). This paper does not consider the specific radiological circumstances surrounding the tragic death of Mr Litvinenko; rather, it provides an evaluation of published human and animal data and models developed for the estimation of alpha radiation doses from 210 Po and the induction of potentially fatal damage to different organs and tissues. Although uncertainties have not been addressed comprehensively, the reliability of key assumptions is considered. Concentrating on the possibility of intake by ingestion, the use of biokinetic and dosimetric models to estimate organ and tissue doses from 210 Po is examined and model predictions of the time-course of dose delivery are illustrated. Estimates are made of doses required to cause fatal damage, taking account of the possible effects of dose protraction and the relative biological effectiveness (RBE) of alpha particles compared to gamma and x-rays. Comparison of LD 50 values (dose to cause death for 50% of people) for different tissues with the possible accumulation of dose to these tissues suggests that bone marrow failure is likely to be an important component of multiple contributory causes of death occurring within a few weeks of an intake by ingestion. Animal data on the effects of 210 Po provide good confirmatory evidence of intakes and doses required to cause death within about 3 weeks. The conclusion is reached that 0.1-0.3 GBq or more absorbed to blood of an adult male is likely to be fatal within 1 month. This corresponds to ingestion of 1-3 GBq or more, assuming 10% absorption to blood. Well-characterised reductions in white cell counts would be observed. Bone marrow failure is likely to be compounded by damage caused by higher doses to other organs, including kidneys and liver. Even if the bone marrow could be rescued, damage to other organs can be expected

  16. Polonium-210 in food and tobacco

    Energy Technology Data Exchange (ETDEWEB)

    Ali, S K [Sudan Academy of Science, Atomic Energy Research Coordination Council, Khartoum (Sudan)

    2006-04-15

    The objective of this study is concerned with the radioactivity in food and tobacco, derived mainly from {sup 210}Po which contribute to the radiation dose received through diet and smoking. This subject was covered under four chapters. Chapter one deals with historical background of polonium-210 and its behavior in living system. Sources of polonium-210 in food and tobacco are explained in the second chapter. Relevant issues such as separation and measurement of polonium-210 covered in subsequent chapter. Chapter four reviewed recent studies on polonium-210. It was found that the main source of this radionuclide is the phosphatic fertilizers that used in food and tobacco cultivation. These fertilizers contain the decay products of {sup 238}U series of which {sup 210}Po is known to be very important from environmental point of view. Many studies conducted showed that the committed effective dose derived mainly from {sup 210} Po due to the consumption of food, particularly sea food is significant, furthermore {sup 210}Po in tobacco is known to be the main cause of many diseases such as lung cancer.(Author)

  17. Polonium-210 in food and tobacco

    International Nuclear Information System (INIS)

    Ali, S.K.

    2006-04-01

    The objective of this study is concerned with the radioactivity in food and tobacco, derived mainly from 210 Po which contribute to the radiation dose received through diet and smoking. This subject was covered under four chapters. Chapter one deals with historical background of polonium-210 and its behavior in living system. Sources of polonium-210 in food and tobacco are explained in the second chapter. Relevant issues such as separation and measurement of polonium-210 covered in subsequent chapter. Chapter four reviewed recent studies on polonium-210. It was found that the main source of this radionuclide is the phosphatic fertilizers that used in food and tobacco cultivation. These fertilizers contain the decay products of 238 U series of which 210 Po is known to be very important from environmental point of view. Many studies conducted showed that the committed effective dose derived mainly from 210 Po due to the consumption of food, particularly sea food is significant, furthermore 210 Po in tobacco is known to be the main cause of many diseases such as lung cancer.(Author)

  18. Laser-assisted decay and optical spectroscopy studies of neutron-deficient thallium isotopes

    CERN Document Server

    Van Beveren, Céline; Huyse, Mark

    The neutron-deficient thallium isotopes with one proton less than the Z = 82 shell closure, are situated in an interesting region of the nuclear chart, notorious for intruder states and shape coexistence. Shape coexistence is the remarkable phenomenon in which two or more distinct types of deformation occur at low energy in the same atomic nucleus. Shape coexistence has been studied intensively, experimentally as well as theoretically in different nuclei in the light-lead region and the isomerism in the thallium isotopes was among the first indications of this phenomenon. Different shapes, whose structure has been linked to specific proton orbitals above and below the Z = 82 shell closure, are present at low energy in the neutron-deficient odd-mass thallium nuclei. In the odd-odd nuclei, the coupling of an unpaired proton and unpaired neutron gives rise to multiplets of low-lying states from which some can be isomeric. Since thallium has one proton missing in the major proton shell, and when approaching neutr...

  19. Influence of isovector pairing and particle-number projection effects on spectroscopic factors for one-pair like-particle transfer reactions in proton-rich even-even nuclei

    Science.gov (United States)

    Benbouzid, Y.; Allal, N. H.; Fellah, M.; Oudih, M. R.

    2018-04-01

    Isovector neutron-proton (np) pairing and particle-number fluctuation effects on the spectroscopic factors (SF) corresponding to one-pair like-particle transfer reactions in proton-rich even-even nuclei are studied. With this aim, expressions of the SF corresponding to two-neutron stripping and two-proton pick-up reactions, which take into account the isovector np pairing effect, are established within the generalized BCS approach, using a schematic definition proposed by Chasman. Expressions of the same SF which strictly conserve the particle number are also established within the Sharp-BCS (SBCS) discrete projection method. In both cases, it is shown that these expressions generalize those obtained when only the pairing between like particles is considered. First, the formalism is tested within the Richardson schematic model. Second, it is applied to study even-even proton-rich nuclei using the single-particle energies of a Woods-Saxon mean-field. In both cases, it is shown that the np pairing effect and the particle-number projection effect on the SF values are important, particularly in N = Z nuclei, and must then be taken into account.

  20. Identification of excited states in 167Os and 168Os: shape coexistence at extreme neutron deficiency

    International Nuclear Information System (INIS)

    Joss, D.T.; King, S.L.; Page, R.D.; Simpson, J.; Keenan, A.; Amzal, N.; Baeck, T.; Bentley, M.A.; Cederwall, B.; Cocks, J.F.C.; Cullen, D.M.; Greenlees, P.T.; Helariutta, K.; Jones, P.M.; Julin, R.; Juutinen, S.; Kankaanpaeae, H.; Kettunen, H.; Kuusiniemi, P.; Leino, M.; Muikku, M.; Savelius, A.; Uusitalo, J.; Williams, S.J.

    2001-01-01

    Excited states in the very neutron-deficient isotopes 167 Os and 168 Os have been observed using the reaction 112 Sn( 58 Ni, 2pxn). The JUROSPHERE γ-ray spectrometer array was used in conjunction with the RITU gas-filled recoil separator to collect prompt γ radiation in coincidence with recoils implanted in a silicon strip detector located at the focal plane of RITU. Using a selective recoil decay tagging technique it has been possible to unambiguously assign γ-ray transitions to 167 Os and 168 Os through the characteristic α radioactivity of these nuclides. The high-spin structure of the bands is discussed in terms of quasiparticle configurations within the framework of the cranked shell model. The role of shape coexistence in 168 Os is examined with phenomenological three-band mixing calculations

  1. Commissioning of a new photon detection system for charge radii measurements of neutron-deficient Ca

    Science.gov (United States)

    Watkins, J.; Garand, D.; Miller, A. J.; Minamisono, K.; Everett, N.; Powel, R. C.; Maaß, B.; Nörtershäuser, W.; Kalman, C.; Lantis, J.; Kujawa, C.; Mantica, P.

    2017-09-01

    Calcium is unique for its possession of two stable isotopes of ``doubly magic'' nuclei at proton and neutron numbers (Z , N) = (20 , 20) and (20 , 28) . Recent charge radii measurements of neutron-rich calcium isotopes yielded an upward trend beyond current theoretical predictions. At the BECOLA facility at NSCL/MSU, Ca charge radii measurements will be extended to the neutron-deficient regime using collinear laser spectroscopy. A new photon detection system with an ellipsoidal reflector and a compound parabolic concentrator has been commissioned for the experiment. The system increases the signal-to-noise ratio by reducing background, which is critical for the low production rates of the Ca experiment. Details of the system and results of the characterization tests will be discussed. Work supported in part by NSF Grant PHY-15-65546, U.S. DOE Grant DE-NA0002924 and by the Deutsche Forschungsgemeinschaft Grant SFB 1245.

  2. Analysis of polonium-210 in food samples

    International Nuclear Information System (INIS)

    Bueno, Luciana; Cunha, Ieda Irma Lamas

    1999-01-01

    This paper presents the polonium levels in food products. The analysis procedure consisted of acid leaching of the samples, solution evaporation, addition of hydrochloric acid, spontaneous deposition of polonium on a silver disk counting by alpha spectroscopy. The method was applied in reference materials and in foodstuffs, resulting in the following values: tea samples 0.4 to 1.7 Bq/unit; fish = 0.17 to 0.40 Bq/Kg, fruits = 0.048 to 0.067 Bq/kg, vegetables = 0.12 to 0.31 Bq/kg, cereal = 0.036 to 0.042 Bq/kg and legumes = 0.024 to 0.51 Bq/kg. The results are very important for public health due to the possible effects to the human organism by the ingestion of contaminated foodstuffs. (author)

  3. Towards 100Sn: Studies on neutron-deficient even isotopes of tin

    International Nuclear Information System (INIS)

    Rathke, G.E.

    1987-02-01

    Neutron-deficient 108,106,104 Sn isotopes were produced by heavy ion induced fusion reactions using high-intensity 59 Ni beams from the UNILAC of the GSI. Their decay properties were studied by techniques of gamma and conversion electron spectroscopy employing the mass separator on-line to the UNILAC. Earlier information on the 108 Sn → 108 In and 106 Sn → 106 In decays was complemented and improved in the course of this work. The new nucleus 104 Sn and its decay to excited states in 104 In was identified and studied for the first time. These investigations yield the following results: the mass of 104 Sn and of nuclei linked to it by alpha decay or proton radioactivity, 108 Te, 112 Xe and 109 I, 113 Cs, respectively were determined from the measured Q EC value of 104 Sn and the known mass value of 104 In. These are nuclei very close or beyond the proton drip line. In addition, information on the quenching of the fast Gamow-Teller beta decay of the even neutron-deficient tin isotopes was obtained. This complements investigations on the N = 50 isotones 94 Ru and 96 Pd, and allows a systematic comparison of these transition strengths for nuclei near the doubly magic 100 Sn. The spreading of the vertical strokeπg 9/2 -1 vg 7/2 , 1 + > configuration over several states, due to residual interactions, and the centroid energies of these magnetic dipole states were determined for the corresponding odd-odd indium isotopes. (orig./HSI)

  4. Polonium evaporation and adhesion experiments for the development of polonium filter in lead-bismuth cooled reactors

    International Nuclear Information System (INIS)

    Obara, Toru; Koga, Takeru; Miura, Terumitsu; Sekimoto, Hiroshi

    2008-01-01

    Fundamental experiments were performed to determine the adhesion characteristics of polonium to different metals and to develop a filter for polonium evaporated from neutron-irradiated LBE. The results of the first experiments suggested that adhesion characteristics are almost the same for stainless steel and nickel metal. The results of the preliminary experiments for a polonium filter suggested that stainless steel mesh with thin wires could effectively collect polonium evaporated from neutron-irradiated LBE. In the experiments, stainless steel wire mesh was used, but from the results of adhesion experiment, it is expected that the same effect can be obtained with wire mesh made of other kinds of metal. (author)

  5. Study of the first collective levels of the even-even nuclei between masses 182 and 206; Etude des premiers niveaux collectifs des noyaux pairs-pairs entre les masses 182 et 206

    Energy Technology Data Exchange (ETDEWEB)

    Barloutaud, R; Leveque, A; Lehmann, P; Quidort, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    The reduced probabilities of deexcitation of the first two 2 + levels of {sup 184}W, {sup 186}W, {sup 188}Os, {sup 190}Os, {sup 192}Os and {sup 194}Pt have been deduced from coulombic excitation experiments on these nuclei.The results are included in a chart of the properties of the first two 2 + levels of even-even nuclei situated between masses 182 and 206. The variation of these properties as a function of nuclear distortion is compared with the various theoretical predictions concerning vibration levels. (author) [French] Les probabilites reduites de desexcitation des deux premiers niveaux 2 + de {sup 184}W, {sup 186}W, {sup 188}Os, {sup 190}Os, {sup 192}Os and {sup 194}Pt ont ete deduites des experiences d'excitation coulombienne de ces noyaux. Les resultats sont inseres dans une systematique des proprietes des deux premiers niveaux 2 + des noyaux pairs-pairs situes entre les masses 182 et 206. La variation de ces proprietes en fonction de la deformation nucleaire est comparee aux diverses predictions theoriques concernant les niveaux de vibration. (auteur)

  6. Impact of microorganism on polonium volatilization

    International Nuclear Information System (INIS)

    Momoshima, N.; Ishida, A.; Fukuda, A.; Yoshinaga, C.

    2007-01-01

    Volatilization of polonium by microorganisms, Chromobacterium violaceum, Escherichia coli and Bacillus subtilis was examined for pure cultures in LB medium at 30 deg C, showing relative Po emission intensity 100, 10 and 1, respectively. Chromobacterium violaceum pre-cultured in LB medium without Po and suspended in water with Po showed high Po volatilization in spite of poor nutriment condition. Antibiotics inhibit volatilization of Po and cultivation at low temperature greatly reduced volatilization. The results strongly support the biological effects on Po volatilization. (author)

  7. Coulomb excitation of $^{182-184}$ Hg: Shape coexistence in the neutron-deficient lead region

    CERN Multimedia

    We put forward a study of the interplay between individual nucleon behavior and collective degrees of freedom in the nucleus, as manifested in shape coexistence in the neutron-deficient lead region. As a first step of this experimental campaign, we propose to perform Coulomb excitation on light mercury isotopes to probe their excited states and determine transitional and diagonal E2 matrix elements, especially reducing the current uncertainties. The results from previous Coulomb excitation measurements in this mass region performed with 2.85 MeV/u beams from REX-ISOLDE have shown the feasibility of these experiments. Based on our past experience and the results obtained, we propose a detailed study of the $^{182-184}$Hg nuclei, that exhibit a pronounced mixing between 2 low-lying excited states of apparently different deformation character, using the higher energy beams from HIE-ISOLDE which are crucial to reach our goal. The higher beam energy should result in an increased sensitivity with respect to the qua...

  8. Nuclear structure studies in highly neutron-deficient (114,116)Xe

    Science.gov (United States)

    Degraaf, James Hendrick

    Lifetimes of nuclear states in 114Xe and 116Xe were measured for the first time; these nuclei represent the most neutron-deficient isotopes of xenon for which lifetimes have now been measured. The fusion-evaporation reactions 58Ni(60Ni, 2p)116Xe at 223 MeV beam energy and 58Ni(58Ni, 2p)114Xe at 215 MeV beam energy were used. Lifetimes were measured using the Recoil Distance Method (RDM) with the 8π gamma-ray spectrometer at Chalk River Laboratories. The new measurements of the B(E2;2+/to 0+) strength in these nuclei, coupled with the recent measurements for heavier xenon isotopes, are well described within the framework of the O(6) symmetry limit of the Interacting Boson Approximation. The octupole nature of the negative parity side-band was also studied, and the lifetime measurements indicate a change from a K/approx 3 structure in heavier xenon isotopes to a K/approx 0,/ 1 structure in 114Xe.

  9. Electron-capture delayed fission properties of neutron-deficient einsteinium nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Shaughnessy, Dawn A. [Univ. of California, Berkeley, CA (United States)

    2000-01-01

    Electron-capture delayed fission (ECDF) properties of neutron-deficient einsteinium isotopes were investigated using a combination of chemical separations and on-line radiation detection methods. 242Es was produced via the 233U(14N,5n)242Es reaction at a beam energy of 87 MeV (on target) in the lab system, and was found to decay with a half-life of 11 ± 3 seconds. The ECDF of 242Es showed a highly asymmetric mass distribution with an average pre-neutron emission total kinetic energy (TKE) of 183 ± 18 MeV. The probability of delayed fission (PDF) was measured to be 0.006 ± 0.002. In conjunction with this experiment, the excitation functions of the 233U(14N,xn)247-xEs and 233U(15N,xn)248-xEs reactions were measured for 243Es, 244Es and 245Es at projectile energies between 80 MeV and 100 MeV.

  10. Heavy neutron-deficient radioactive beams: fission studies and fragment distributions

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, K.H.; Benlliure, J.; Heinz, A.; Voss, B. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Boeckstiegel, C.; Grewe, A.; Steinhaeuser, S.; Clerc, H.G.; Jong, M. de; Junghans, A.R.; Mueller, J. [Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik; Pfuetzner, M. [Warsaw Univ. (Poland). Inst. of Experimental Physics

    1998-02-01

    The secondary-beam facility of GSI Darmstadt was used to study the fission process of short-lived radioactive nuclei. Relativistic secondary projectiles were produced by fragmentation of a 1 A GeV {sup 238}U primary beam and identified in nuclear charge and mass number. Their production cross sections were determined, and the fission competition in the statistical deexcitation was deduced for long isotopical chains. New results on the enhancement of the nuclear level density in spherical and deformed nuclei due to collective rotational and vibrational excitations were obtained. Using these reaction products as secondary beams, the dipole giant resonance was excited by electromagnetic interactions in a secondary lead target, and fission from excitation energies around 11 MeV was induced. The fission fragments were identified in nuclear charge, and their velocity vectors were determined. Elemental yields and total kinetic energies have been determined for a number of neutron-deficient actinides and preactinides which were not accessible with conventional techniques. The characteristics of multimodal fission of nuclei around {sup 226}Th were systematically investigated and related to the influence of shell effects on the potential energy and on the level density between fission barrier and scission. A systematic view on the large number of elemental yields measured gave rise to a new interpretation of the enhanced production of even elements in nuclear fission and allowed for a new understanding of pair breaking in large-scale collective motion. (orig.)

  11. Electron-capture delayed fission properties of neutron-deficient einsteinium nuclei

    International Nuclear Information System (INIS)

    Shaughnessy, Dawn A.

    2000-01-01

    Electron-capture delayed fission (ECDF) properties of neutron-deficient einsteinium isotopes were investigated using a combination of chemical separations and on-line radiation detection methods. 242 Es was produced via the 233 U( 14 N,5n) 242 Es reaction at a beam energy of 87 MeV (on target) in the lab system, and was found to decay with a half-life of 11 ± 3 seconds. The ECDF of 242 Es showed a highly asymmetric mass distribution with an average pre-neutron emission total kinetic energy (TKE) of 183 ± 18 MeV. The probability of delayed fission (P DF ) was measured to be 0.006 ± 0.002. In conjunction with this experiment, the excitation functions of the 233 U( 14 N,xn) 247-x Es and 233 U( 15 N,xn) 248-x Es reactions were measured for 243 Es, 244 Es and 245 Es at projectile energies between 80 MeV and 100 MeV

  12. Decay studies of new neutron deficient isotopes in the range of elements between gadolinium and lead

    CERN Document Server

    Hofmann, S; Faust, W; Guttner, K; Hessberger, F P; Münzenberg, G; Reisdorf, W; Schneider, J H R; Thuma, B

    1981-01-01

    Very neutron deficient isotopes below lead are produced with beams of /sup 58/Ni, /sup 92/Mo, and /sup 107/Ag accelerated by the linear accelerator UNILAC. After separation from the projectile beam by the velocity filter SHIP, the fusion products are implanted with their full recoil energy into an array of position-sensitive detectors. With a newly developed position and time correlation technique, parent daughter relationships, half lives and alpha branching ratios of a large number of isotopes are determined. Two new alpha emitting isomeric states are identified in /sup 155/Lu and /sup 156/Hf. The energies of the excited states are (1798+or-12) keV in /sup 155/Lu and (1977+18) keV in /sup 156/Hf, the half-lives are (2.60+or-0.07) ms and (444+or-17) mu s, respectively. Compared to the ground state transitions, a hindrance of 10/sup 5/ can be deduced for both transitions, possibly indicating orbital angular momenta of the order of 10 h(cross) for the alpha emitting states. The isomers are proposed to belong t...

  13. Study of the Neutron Deficient Pb and Bi Isotopes by Simultaneous Atomic- and Nuclear-Spectroscopy

    CERN Multimedia

    Kessler, T

    2002-01-01

    We propose to study systematically nuclear properties of the neutron deficient lead $^{183-189}$Pb, $^{191g}$Pb, $^{193g}$Pb and bismuth isotopes $^{188-200}$Bi by atomic spectroscopy with the ISOLDE resonance ionisation laser ion source (RILIS) combined with simultaneous nuclear spectroscopy at the detection set-up. The main focus is the determination of the mean square charge radii of $^{183-190}$Pb and $^{188-193}$Bi from which the influence of low-lying intruder states should become obvious. Also the nuclear spin and magnetic moments of ground-states and long-lived isomers will be determined unambiguously through evaluation of the hyperfine structure, and new isomers could be discovered. The decay properties of these nuclei can be measured by $\\alpha$-$\\gamma$ and $\\beta$-$\\gamma$ spectroscopy. With this data at hand, possible shape transitions around mid-shell at N$\\sim$104 will be studied. This data is crucial for the direct test of nuclear theory in the context of intruder state influence (e.g. energy ...

  14. Long-lived high-spin isomers in the neutron-deficient 1g sub(9/2)-shell nuclei

    International Nuclear Information System (INIS)

    Ogawa, K.

    1981-09-01

    The neutron-deficient 1g sub(9/2)-shell nuclei are studied in the framework of the shell model with active nucleons occuping the 1g sub(9/2) and 2p sub(1/2) shells. The calculated result for 95 Pd shows good agreement with the recent experiment by Nolte and Hick. Many ''spin-gap'' Isomers are predicted in the region of A = 76 -- 84 and A = 95 -- 100. (author)

  15. Polonium 210 content in foodstuffs produced in Bulgaria

    International Nuclear Information System (INIS)

    Keslev, D.; Novakova, E.; Boyadzhiev, A.; Kerteva, A.

    1975-01-01

    A study of the content of polonium-210 in a variety of foodstuffs produced in Bulgaria in 1970 revealed peak radionuclide concentration in wheat - 6.7 pCi/kg, followed by prunes - 2.2 pCi/kg, cabbage - 1.86 pCi/kg, peppers - 1.64 pCi/kg. The content of polonium-210 in onions, meat and potatoes was low (0.5, 0.8 and 0.9 pCi/kg accordingly). All other food products studied - milk, bread, beans, eggs, tomatoes, apples, pears, grapes and drinking water - appeared to have approximately equal polonium-210 concentration - from 1.21 to 1.35 pCi/kg. The daily intake of polonium-210 with food and water amounted accordingly to 1.61, 1.79 and 2.08 pCi/kg in preschool children, in school children and in senile individuals. The major part (68 - 82 per cent) of incorporated polonium-210 was eliminated with the stools. In all age groups the amount of polonium-210 removed daily from the body with the excreta corresponded to the intake, i.e. the balance of polonium-210 was in a state of equilibrium. The age factor in all three groups exerted no effect on the radionuclide intake and elimination from the body. (Ch.K.)

  16. Decay of new mass-separated neutron-deficient La and Ce isotopes

    International Nuclear Information System (INIS)

    Genevey, J.; Gizon, A.; Idrissi, N.; Weiss, B.; Beraud, R.; Charvet, A.; Duffait, R.; Emsallem, A.; Meyer, M.; Ollivier, T.; Redon, N.

    1987-01-01

    By use of a He jet system coupled to a Bernas-Nier ion-source, several new mass-separated A = 122 - 127 isotopes reached in heavy ion fusion reactions at SARA have been identified and studied. From experimental decay properties of La isotopes, systematics of low-lying energy levels have been extended for even-even and odd-A barium. New informations on Ce decay schemes are briefly reported

  17. The Litvinenko polonium-210 case - German experiences

    International Nuclear Information System (INIS)

    Kirchner, Gerald; Kroeger, Emily A.

    2008-01-01

    This paper brings together the measurement results taken and the lessons learned by the German Federal Office for Radiation Protection during the polonium-210 incident in Hamburg in late 2006. The incident was pivotal in confirming the importance of the defence against nuclear hazards in Germany and for highlighting the role of communication in the success of a deployment. The background of the case is reviewed and an overview of the German defence against nuclear hazards is given. The various measurement tasks, both at the scene and in the laboratory, and their results are summarized along with the communication challenges experienced. The main conclusions are that the traces of polonium-210 found at the sites were of little radiological consequence and the German defence against nuclear hazards in Germany delivered an excellent and measured response to the incident. However, communication challenges still exist and communication with the public and the emergency responders has to be given high priority during future deployments in order to ensure their success. (author)

  18. Collinear laser spectroscopy on radioactive neutron-deficient lead and thallium isotopes

    International Nuclear Information System (INIS)

    Menges, R.

    1989-02-01

    The systematic study of the isotope shift in the neighbourhood of the closed shells was extended in this thesis to Z = 82. The elements lead and thallium were measured up to the mass 190 and 188 and the nuclear moments determined together with the change of the mean square charge radius. The accumulating of the recoil nuclei formed by heavy ion reactions in the bunched ion source of the GSI mass separator could be used in order to study the low-spin isomers with I = 2 of the neutron-deficient thallium isotopes up to A = 190. It is a clearly recognizable isomer shift against the I = 7 isomers shown which changes at A = 194 the sign. A phenomenon which also exists in the element mercury, but for which no sufficient explanation exists. The magnetic moments of the thallium isotopes complete the analysis of Ekstroem (1976) and confirm the choice of the sign of the magnetic moments of the I = 2 isomers. The application of the additivity rule to the odd-odd nuclei shows qualitatively good agreement with the experiment and confirms so the assignment of the configuration of the contributing nuclear states. The quadrupole moments show a slight oblate deformation of the 9/2 - intruder states. The moments of the lead isotopes show pronounced one-particle character and by this the nearly spherical shape of nuclei with closed proton shell. The deviation from the linear slope of the mean square radius of the lead isotopes onsetting at A = 194 cannot be explained by the mixing of the 0 1 + ground state with the deformed 0 2 + intruder state. The odd - even staggering and the buckling of the charge radii at the shell closure are very well reproduced by Hartree-Fock calculations which regard the 3- and 4-particle interactions in the nucleus. (orig.) [de

  19. Measurement of polonium activity in Indian tobacco

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D R; Nilekani, S R [Bhabha Atomic Research Centre, Bombay (India). Div. of Radiation Protection

    1976-10-01

    To assess the probable induction of lung cancer due to /sup 210/Po in Indian tobacco, 116 samples of tobacco drawn from seven brands of cigarettes, cigars, cheroots and local beedi fillings were assayed. The results are tabulated and show an average /sup 210/Po content for cigarettes varying from 0.07 to 0.10 pCi/g except for one brand which had a higher value of 0.152 pCi/g. Large cigars were shown to have less polonium content compared to other tobacco products such as cheroot, beedi fillings and small cigars. From the data obtained the lung burden of a smoker of Indian cigarettes has been calculated to be 23.6 mrad/day which is between 3 and 6 times higher than that due to natural background of radon and thoron in the atmosphere.

  20. Study of proton and 2 protons emission from light neutron deficient nuclei around A=20

    International Nuclear Information System (INIS)

    Zerguerras, T.

    2001-09-01

    Proton and two proton emission from light neutron deficient nuclei around A=20 have been studied. A radioactive beam of 18 Ne, 17 F and 20 Mg, produced at the Grand Accelerateur National d'Ions Lourds by fragmentation of a 24 Mg primary beam at 95 MeV/A, bombarded a 9 Be target to form unbound states. Proton(s) and nuclei from the decay were detected respectively in the MUST array and the SPEG spectrometer. From energy and angle measurements, the invariant mass of the decaying nucleus could be reconstructed. Double coincidence events between a proton and 17 F, 16 O, 15 O, 14 O and 18 Ne were registered to obtain excitation energy spectra of 18 Ne, 17 F, 16 F, 15 F et 19 Na. Generally, the masses measures are in agreement with previous experiments. In the case of 18 Ne, excitation energy and angular distributions agree well with the predictions of a break up model calculation. From 17 Ne proton coincidences, a first experimental measurement of the ground state mass excess of 18 Na has been obtained and yields 24,19(0,15)MeV. Two proton emission from 17 Ne and 18 Ne excited states and the 19 Mg ground state was studied through triple coincidences between two proton and 15 O, 16 O and 17 Ne respectively. In the first case, the proton-proton relative angle distribution in the center of mass has been compared with model calculation. Sequential emission from excited states of 17 Ne, above the proton emission threshold, through 16 F is dominant but a 2 He decay channel could not be excluded. No 2 He emission from the 1.288 MeV 17 Ne state, or from the 6.15 MeV 18 Ne state has been observed. Only one coincidence event between 17 Ne and two proton was registered, the value of the one neutron stripping reaction cross section of 20 Mg being much lower than predicted. (author)

  1. Yields of the rare-earth neutron-deficient isotopes in the reactions of Mo isotopes with 40Ca ions

    International Nuclear Information System (INIS)

    Adam, J.; Chaloun, P.; Gangrskij, Yu.P.

    1999-01-01

    The results of the joint Russian-Chinese experiment on the measurements of the reaction cross sections of the rare-earth neutron-deficient isotopes production and the study of their decay scheme are presented. The studied nuclides were obtained in the reactions 92 Mo + 40 Ca and 97 Mo + 40 Ca on the 4-meter cyclotron of the Flerov Laboratory of Nuclear Reactions, JINR. The recoil nuclei were stopped in the inert gas and transported by the gas flow to the detectors. The single and coincidence spectra of γ-, x-rays and delayed protons were measured. The enhanced yield of the reactions with the charge particle evaporation was observed

  2. Extreme accumulations of natural polonium-210 in certain marine organisms

    International Nuclear Information System (INIS)

    Folsom, T.R.; Wong, K.M.; Hodge, V.F.

    1972-01-01

    Concentration levels of polonium-210 reported for sea water are reviewed, and activities accumulated by various marine plant and animal species are discussed. Special mention is made of detailed studies of one giant algae upon whose outer surfaces intense accumulations of polonium have been discovered recently. Some concentrations found in two organisms intimate with algae, the abalones and the sea hares, are reported. Concentrations are listed pertaining to organisms selected from the open ocean in order to show that intense polonium concentrations are not restricted to organisms living near the continents where precursors of polonium originate. A brief discussion of conditions on one of the marine mammals, the dolphin, next is made. Then comments are made upon a benthic species (the sable fish) that prefers to live close to the deep sea floor, presumably so as to eat detritus. They also eat many of the smaller organisms that compete for the natural deep sea fallout of food, and many of these live in close contact with the muds and clays of the sea floor that are rich in radium. Some of the behavior and anatomical features and polonium-210 distribution in one of the most interesting and valuable of fishes, the North Pacific albacore (Thunnus alalunga) is described. This species has been used previously to tell us something about nuclear fallout distributions in the North Pacific Ocean during the past decade and repeatedly has directed attention to features of this ocean that might hardly be detected otherwise. (U.S.)

  3. Experimental investigation of decay properties of neutron deficient $^{116-118}$Ba isotopes and test of $^{112-115}$Ba beam counts

    CERN Multimedia

    We propose to study decay of neutron deficient isotopes $^{116-118}$Ba using Double Sided Silicon Strip Detector (DSSSD). To study delayed-proton and $\\alpha$-decay branching ratios of $^{116-118}$Ba are of special interest because of their vicinity to the proton drip line. The nuclear life-times and properties of the proton unstable states of Cs isotopes, populated through decay of $^{116-118}$Ba isotopes will be measured. In addition to that we propose beam development of $^{112-115}$Ba to study exotic decay properties of these neutron deficient nuclei and to search for super-allowed $\\alpha$-decay in future.

  4. Systematics of even-a polonium isotopes

    International Nuclear Information System (INIS)

    Younes, W.; Cizewski, J.A.; Bernstein, L.A.

    1995-01-01

    Polonium nuclei, with two valence protons, provide fertile ground for the study of the onset of collectivity: from the textbook two-particle levels of 210 Po to the phonon-like multiplets of 196 Po. In their earlier work the authors described the low-lying structure of even-A Po nuclei down to 196 Po as two protons interacting via a surface-δ interaction and adiabatically coupled to a vibrating core. However, this particle-core model (PCM) fails to adequately describe the recently measured level scheme of 194 Po. Also because it assumes a pre-existing vibrational core, this model does not help to understand the single particle contributions to the collective motion. Therefore, the authors have also studied the Po systematics using a more microscopic model: the quasi-particle random phase approximation (QRPA). They will present a phenomenological analysis of the rapidity of the onset of collectivity for the Po isotopes as well as results of both PCM and QRPA calculations. The microscopic nature of the collectivity for the even-A Po isotopes will be discussed

  5. Behaviour of polonium-210 during anode slimes processing

    International Nuclear Information System (INIS)

    Brown, S. A.

    1998-01-01

    Refinery slimes produced during the electrorefining of copper anodes often contain recoverable quantities of gold, silver and the platinum group metals, platinum and palladium. The treatment process selected to recover precious metals from the slimes depends on the concentration of other impurities. Polonium-210 will be present in the refinery slimes when uranium-bearing minerals (e.g. uraninite) are associated with the copper mineralogy. The production of pure precious metals from copper anode slimes containing polonium-210 involves a variety of steps including impurity removal, smelting to produce a dore metal and then refining. Gold and silver are recovered by electrorefining processes. Platinum group metals accumulate in the gold electrolyte and are recovered by precipitation. To ensure that specifications are met in the final products, it is necessary to identify and closely monitor where the impurities, including polonium-210, are partitioning during processing. Although measurement of polonium-210 activity using alpha spectrometry identifies relative amounts of the radionuclide in the various streams, it does not give any indication of the form it may be in. By studying the chemistry and deportment of its neighbours in the periodic table (Pb,Bi,Se and Te) it may be possible to make some conclusions regarding polonium-210 behaviour. Examination of the solid phases produced during anode slimes treatment were carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Elemental analyses of solid and liquor streams were carried out using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAES). This paper attempts to develop a relationship between the behaviour of polonium-210 and other impurities during precious metals recovery based on the results of these studies

  6. Behaviour of polonium-210 during anode slimes processing

    International Nuclear Information System (INIS)

    Brown, S.A.

    1998-01-01

    Refinery slimes produced during the electrorefining of copper anodes often contain recoverable quantities of gold, silver and the platinum group metals, platinum and palladium. The treatment process selected to recover precious metals from the slimes depends on the concentration of other impurities. Polonium 210 will be present in the refinery slimes when uranium-bearing minerals (eg. uraninite) are associated with the copper mineralogy. The production of pure precious metals from copper anode slimes containing polonium-210 involves a variety of steps including impurity removal smelting to produce a dore metal and then refining. Gold and silver are recovered by electrorefining processes. Platinum group metals accumulate in the gold electrolyte and are recovered by precipitation To ensure that specifications are met in the final products, it is necessary to identify and closely monitor where the impurities, including polonium-210, are partitioning during processing. Although measurement of polonium-210 activity using alpha spectrometry identifies relative amounts of the radionuclide in the various streams, it does not give any indication of the form it may be in. By studying the chemistry and deportment of its neighbours in the periodic table (Pb, Bi, Se and Te) it may be possible to make some conclusions regarding polonium-210 behaviour. Examination of the solid phases produced during anode slimes treatment were carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Elemental analyses of solid and liquor streams were carried out using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAES). This paper attempts to develop a relationship between the behaviour of polonium-210 and other impurities during precious metals recovery based on the results of these studies. (author). 5 refs., 4 tabs

  7. Levels of polonium-210 in some beverages and in tobacco

    International Nuclear Information System (INIS)

    Colangelo, C.H.; Huguet, M.R.; Palacios, M.A.; Oliveira, A.A.

    1992-01-01

    The objective of the present work is the estimation of the Polonium-210 content in some beverages and in tobacco, in order to assess the corresponding collective doses to the population in Argentina. Yerba mate, an autochton plant of South America, tea leaves, their infusion and ground coffee were analyzed as well as tobacco. Collective doses due to annual consumption of the beverages described, resulted in values from 6 man.Sv to 1200 man.Sv. Results for Polonium-210 in tobacco ranged from 10 Bq kg -1 . Doses due to the use of tobacco were not assessed since an appropriate metabolic model was not found. (author)

  8. Microscopic analysis of shape transition in neutron-deficient Yb isotopes

    Science.gov (United States)

    Fu, Y.; Tong, H.; Wang, X. F.; Wang, H.; Wang, D. Q.; Wang, X. Y.; Yao, J. M.

    2018-01-01

    The development of nuclear collectivity in even-even Yb-170152 is studied with three types of mean-field calculations: the nonrelativistic Hartree-Fock plus BCS calculation using the Skyrme SLy4 force plus a density-dependent δ pairing force and the relativistic mean-field calculation using a point-coupling energy functional supplemented with either a density-independent δ pairing force or a separable pairing force. The low-lying states are obtained by solving a five-dimensional collective Hamiltonian with parameters determined from the three mean-field solutions. The energy surfaces, excitation energies, electric multiple transition strengths, and differential isotope shifts are presented in comparison with available data. Our results show that different treatments of pairing correlations have a significant influence on the speed of developing collectivity as the increase of neutron number. All the calculations demonstrate the important role of dynamic shape-mixing effects in resolving the puzzle in the dramatic increase of charge radius from 152Yb to 154Yb and the role of triaxiality in Yb 160 ,162 ,164 .

  9. Study of Triaxial deformation variable γ in even - even nuclei

    International Nuclear Information System (INIS)

    Singh, Yuvraj; Gupta, K.K.; Bihari, Chhail; Sharma, Aparna; Varshney, A.K.; Singh, M.; Gupta, D.K.; Varshney, Mani; Dhiman, S.K.

    2011-01-01

    The deformation parameters β and γ of the collective model are basic description of the nuclear equilibrium shape and structure, while values for these variables have been discussed for many nuclei. A systematic study in mass region A = 120-140 and A = 150 -180 can never be less revealing, such study has been presented, in A = 90 -120 for Mo, Ru and Pd nuclei where β and γ both vary strongly

  10. Model of coupled bands in even-even nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Nadzhakov, E G; Nozharov, R M; Myankova, G Z; Antonova, V A [Bylgarska Akademiya na Naukite, Sofia. Inst. za Yadrena Izsledvaniya i Yadrena Energetika

    1979-01-01

    The model is derived in a natural way from the theory of coupled modes. It is based on an expansion of the Hamiltonian in terms of elementary transition operators, including direct rotation-vibration coupling with phonons. The treatment is limited to three types of phonons: ( I = K = 0), S (I = K = 1) and (I = K = 2). The basis of the operators, acting on the ground state is truncated by an inclusion of a reasonable number of phonon states. In the framework of this approximation one may evaluate the matrix elements of the model Hamiltonian and diagonalize it by standard numerical methods to fit the experimental spectrum. The well known picture of band hybridization is obtained as a special case of the model under consideration.

  11. Isotopic shift in even-even barium isotopes

    International Nuclear Information System (INIS)

    Karim, Afaque; Naz, Tabassum; Ahmad, Shakeb

    2017-01-01

    We have discussed the correlation between a nuclear shape and its matter distribution. Here, we present the root-mean-square radii (r rms ) and rms charge radius (r ch ). We have also discussed the isotopic shift in terms of the observable ‹Δr 2 c › N,82 and its differential ‹Δr 2 c › N-2,N . We present nuclear radii evaluated using different interactions. Neutron radii and charge radii for all the isotopic chains are shown. Neutron radii for Ba isotopes show an increasing trend with the neutron number for all isotopic chains. One can observe a clear kink about magic number N=82

  12. Systematic studies for medium-heavy even-even nuclei

    International Nuclear Information System (INIS)

    Chen, Y.; Zhao, Y.M.; Chen, J.Q.

    1995-01-01

    The systematics for the excitation energies of the ground, β, and γ bands are presented using the empirical total np interaction V NP . Some regularities found in the previous studies are tested by the systematics in the V NP schemes. The systematics of the β and γ bands are presented in detail. Elegant regularities are observed for the excitation energies. The correlation phenomenon of the general behavior among different bands within each major shell is pointed out

  13. Search for EC-decayed neutron-deficient actinide isotopes using gas-jet coupled JAERI-ISOL

    Energy Technology Data Exchange (ETDEWEB)

    Tsukada, Kazuaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-07-01

    To study the nuclear properties of unknown neutron deficient actinide isotopes which decay mainly via orbital electron capture (EC), we have developed a composite system consisting of a gas-jet transport apparatus and a thermal ion-source at the JAERI-ISOL. With this system, search for {sup 236}Am produced in the {sup 235}U({sup 6}Li, 5n) reaction has been performed. Pu KX-rays associated with the EC decay of {sup 236}Am are observed at the mass-236 fraction. The half-life of {sup 236}Am is evaluated to be 4.4min. The outline of the gas-jet coupled JAERI-ISOL system and typical performance are given. (author)

  14. Spectroscopy of heavy nuclei by configuration mixing of symmetry restored mean-field states: shape coexistence in neutron-deficient Pb isotopes

    International Nuclear Information System (INIS)

    Bender, M.; Heenen, P.H.; Bonche, P.; Duguet, T.

    2003-01-01

    We study shape coexistence and low-energy excitation spectra in neutron-deficient Pb isotopes using configuration mixing of angular-momentum and particle-number projected self-consistent mean-field states. The same Skyrme interaction SLy6 is used everywhere in connection with a density-dependent zero-range pairing force. (orig.)

  15. Marie Sklodowska-Curie, polonium, radium and radiochemistry

    International Nuclear Information System (INIS)

    Guillaumont, R.

    2011-01-01

    In this work, the author describes how the methodology developed by Marie Curie in discovering polonium and radium has contributed to greater scientific discoveries and how these discoveries have played a great part in the development of science in general and have particularly enriched chemistry. (O.M.)

  16. Polonium assimilation and retention in mule deer and pronghorn antelope

    International Nuclear Information System (INIS)

    Sejkora, K.J.

    1982-01-01

    Excretion kinetics and tissue distribution of polonium-210 in mule deer and pronghorn were studied. Each animal in a captive herd of 7 mule deer and 2 pronghorn received an intraruminal injection of 4.4 μCi of polonium chloride. Feces and urine were collected periodically over a 43-day period and daily excretion rate for each pathway was regressed as a function of time. Assimilation fractions of 0.40 and 0.51 were calculated for mule deer (n=2) and 0.60 for a pronghorn. Body burden retention functions were calculated from integrated excretion rate functions. Polonium burdens in muscle, liver, and kidney were calculated as a fraction of body burden from serially-sacrificed animals. Background tissue burdens in mule deer were comparable to those of other ruminants reported in the literature. Hypothetical cases were assumed which combined feeding rate of mule deer, forage concentrations of polonium, retention function, tissue burden fraction, and human intake to estimate human radiation dose. 26 references

  17. Radiocaesium and polonium in seals from Swedish coastal waters

    International Nuclear Information System (INIS)

    Holm, E.A.B.; Leisvik, M.A.; Holm, E.A.B

    2004-01-01

    Radiocaesium, 137 Cs (T 1/2 = 30 a) and 210 Po (T 1/2 = 138 d) have been studied in tissues (muscle, liver, kidney and gonads/ovaries) from a large number of seals from the Baltic Sea and the Swedish west coast during 1995-2002. The Baltic Sea is a marginal sea with long residence time for dissolved compounds. Concentrations of radiocaesium increased 10 fold in the Baltic Sea following the Chernobyl accident, while concentrations of polonium can be supposed to be in equilibrium except for seasonal variations. The major food for seals in the Baltic proper is fish, while at the west coast other food stuff such as crustaceans play an important role. By supposing that the seals consume 5% of their body-weight per day and by using known data for caesium and polonium in fish the biological half-life in seals is estimated to 20 days for Caesium and 35 days for Polonium. Radiocaesium is evenly distributed in the organs of the seals and was about 100 Bq kg -1 in the Baltic Sea while at the west coast the concentrations were significantly lower, about 5-30 Bq kg -1 . Polonium shows the highest concentrations in kidney, about 100-200 Bq kg -1 d.w. in the Baltic sea and higher concentrations 100-1000 Bq kg -1 at the west coast. This reflects clearly the differences in food choice/availability in the different areas. The estimated maximal doses were 76 μSv per year to muscle from 137 Cs and 6.8 mSv from 210 Po to kidney. Seals constitute a good bio-marker for radioactivity in Swedish coastal waters. Concentration factors are higher for radiocaesium in the Baltic Sea due to lower salinity and consequently higher concentrations in fish compared to other areas, but lower for polonium than in areas where crustaceans also constitute an important foodstuff. (author)

  18. Characteristics of polonium contamination from neutral irradiated lead-bismuth eutectic

    International Nuclear Information System (INIS)

    Miura, T.; Obara, T.; Sekimoto, H.

    2004-01-01

    After neutron capture, bismuth-209 changes to polonium-210 that emits α-particles. Lead-Bismuth eutectic (LBE) in reactor system contaminates the system by polonium. We analyzed adsorbed materials from melted LBE on quartz glass plate. Lead, bismuth and their oxides were confirmed in adsorbed materials. And, we evaluated the baking method in vacuum for removal of polonium and adsorbed materials on quartz glass plate. It was evaluated that it is possible to remove almost all the polonium from the quartz glass plate by baking at temperature more than 300 C. degrees. Unfolding method was applied to calculate polonium distribution in LBE ingot. From measured α-particle pulse height distribution, the polonium distribution in depth of LBE ingot was calculated using quadratic programming code, where response functions are calculated by Monte Carlo method. (authors)

  19. The properties of atomic nuclei at the boundary of proton instability, discussed at the example of very neutron deficient isotopes in the mass range 100-150

    International Nuclear Information System (INIS)

    Roeckl, E.

    1981-10-01

    In this paper it shall be tried to strike the balance after the first years of experimenting at the on-line mass separator of the GSI Darmstadt and to present the main results of the study of very neutron deficient isotopes in the mass range 90-150 as well as the resulting questions for further experiments. First some foundations concerning the properties of neutron deficient nuclei and the measuring method are explained. The results and their interpretation are discussed using examples for the alpha decay, the beta decay, the mass-energy-area, and the proton-drip line. Finally the obtained results are summarized, and an outlook to further studies of nuclear properties far from beta stability is given. (orig.) [de

  20. Measurements of electric quadrupole moments of neutron-deficient Au, Pt, and Ir nuclei with NMR-ON in hcp-Co

    CERN Multimedia

    Smolic, E; Hagn, E; Zech, E; Seewald, G

    2002-01-01

    The aim of the experiments is the measurement of $\\,$i) nuclear magnetic moments and electric quadrupole moments of neutron-deficient isotopes in the region Os-Ir-Pt-Au with the methods of quadrupole-interaction-resolved NMR on oriented nuclei " QI-NMR-ON " and modulated adiabatic passage on oriented nuclei " MAPON " and $\\,$ii) the magnetic hyperfine field, electric field gradient (EFG), and spin-lattice relaxation of 5d elements in ferromagnetic Fe, Ni, fcc-Co and hcp-Co.\\\\ The measurements on Au isotopes have been finished successfully. The quadrupole moments of $^{186}$Au, $^{193m}$Au, $^{195}$Au, $^{195m}$Au, $^{197m}$Au, $^{198}$Au and $^{199}$Au were determined with high precision.\\\\ For neutron-deficient Ir isotopes QI-NMR-ON measurements were performed after implantation of Hg precursors. The EFG of Ir in hcp-Co has been calibrated. Thus precise values for the spectroscopic quadrupole mo...

  1. Polonium-210 and lead-210 contamination of plants

    Energy Technology Data Exchange (ETDEWEB)

    Popova, O N; Taskaev, A I

    1977-01-01

    A model experiment with a water culture of barley grown in closed vessels, with an increased content of radon-222 in the air, has demonstrated an intensive contamination of the overground part and roots of the plant with polonium-210 and lead-210. Roots having no overground part were affected by radionuclides in a similar way as those of intact plants. Contamination was minimal in the plants grown from soil cultures.

  2. Evolution of collective motion in light polonium nuclei

    International Nuclear Information System (INIS)

    Cizewski, J. A.

    1998-01-01

    The γ-ray spectroscopy of even- and odd-mass isotopes of polonium have been studied using arrays of Ge detectors coupled to recoil-mass analyzers, including recoil-decay tagging techniques. The level energies and B(E2) branching ratios can be reproduced by theoretical frameworks which do not explicitly include proton particle-hole excitations across the Z = 82 shell, conclusions in contrast to those deduced from alpha-decay measurements

  3. Adsorption of volatile polonium species on metals in various gas atmospheres. Pt. II. Adsorption of volatile polonium on platinum, silver and palladium

    Energy Technology Data Exchange (ETDEWEB)

    Maugeri, Emilio Andrea; Joerg Neuhausen; Dressler, Rugard; Piguet, David; Voegele, Alexander; Schumann, Dorothea [Paul Scherrer Institut (PSI), Villigen (Switzerland). Lab. for Radiochemistry; Misiak, Ryszard [The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Eichler, Robert [Paul Scherrer Institut (PSI), Villigen (Switzerland). Lab. for Radiochemistry; Bern Univ. (Switzerland). Dept. for Chemistry and Biochemistry

    2016-07-01

    This work presents the results obtained from studying the interaction between polonium compounds formed in different atmospheres and platinum, palladium and silver surfaces obtained by thermochromatography. These results are of crucial importance for the design of cover gas filter systems for lead-bismuth eutectic (LBE)-based nuclear facilities such as accelerator driven systems (ADS). The results obtained from studying the interaction of polonium and platinum under inert atmosphere and reducing atmospheres with and without addition of moisture show that polonium is deposited at temperatures between 993 and 1221 K, with adsorption enthalpies ranging from -235 to -291 kJ mol{sup -1}, indicating a very strong adsorption of the polonium species present on platinum surfaces. The interaction between polonium and silver was investigated using purified inert, reducing and oxidizing carrier gases. Results show a deposition temperature between 867 and 990 K, with adsorption enthalpies ranging from -205 to -234 kJ mol{sup -1}. The interaction of polonium and palladium was studied in purified helium and purified hydrogen. For both conditions a deposition temperature of 1221 K was observed corresponding to an adsorption enthalpy of -340 kJ mol{sup -1}. No highly volatile polonium species was formed at any of the applied experimental conditions.

  4. Fundamental study of polonium contamination by neutron irradiated lead-bismuth eutectic

    International Nuclear Information System (INIS)

    Obara, T.; Miura, T.; Sekimoto, H.

    2005-01-01

    As a fundamental study of polonium contamination by neutron irradiated LBE, it was investigated to remove polonium surface contamination by baking method. The baking experiments were performed using quartz glass plates contaminated by material evaporated from neutron irradiated LBE liquid. The contaminated quartz glass plates were baked in vacuum (2 Pa) at various temperatures. The experimental results clearly show that polonium evaporated from LBE can be removed by baking samples at temperatures 300 deg. C and above. It is of note that the decrease in the weight of deposited materials baked at 300 deg. C differed from that observed at 400 deg. C or higher temperatures. At temperature of 300 deg. C, no change in weight was observed. The mass of polonium in the LBE samples was so small that no weight change could be observed by release of polonium. Thus, it might show that only the polonium among the adherent materials was removed by baking at 300 deg. C without removing other adhered material. The method is rather simple, so it is easy to apply the method for practical application. One of the expected applications may be the removal of polonium contamination in a primary loop before maintenance work of the loop. Also it shows that this method can be used to avoid the release of polonium from contaminated material, in case of an accident, by keeping the contaminated material at low temperature

  5. Foliar retention, transport and leaching of polonium-210 and lead-210

    Energy Technology Data Exchange (ETDEWEB)

    Athalye, V V; Mistry, K B

    1972-01-01

    Polonium-210 and lead-210, the long-lived daughter radionuclides of gaseous radon-222, are deposited on plant surfaces under conditions of atmospheric washout. Foliar retention, transport and leaching of these radionuclides in Red Kidney beans were investigated in nutrient culture experiments. Under identical conditions, over 90 percent of foliar applied radiolead was retained by the plant while only about 30 percent of polonium was retained. Over a 48-hr period small quantities of polonium were translocated from the treated leaflet to other parts of the plant. By comparison, radiolead was totally immobilized at the site of retention. Leachability of root absorbed radiolead from bean leaves was 20-fold greater than that of polonium. The marked differences in the extent of foliar retention, translocation and leaching of polonium and radiolead could significantly affect the levels of these long-lived radionuclides attained in plants.

  6. Adsorption of volatile polonium and bismuth species on metals in various gas atmospheres. Pt. I. Adsorption of volatile polonium and bismuth on gold

    Energy Technology Data Exchange (ETDEWEB)

    Maugeri, Emilio Andrea; Neuhausen, Joerg; Dressler, Rugard; Piguet, David; Voegele, Alexander; Schumann, Dorothea [Paul Scherrer Institut (PSI), Villigen (Switzerland). Lab. for Radiochemistry; Eichler, Robert [Paul Scherrer Institut (PSI), Villigen (Switzerland). Lab. for Radiochemistry; Bern Univ. (Switzerland). Dept. for Chemistry and Biochemistry; Rijpstra, Kim [Ghent Univ., Zwijnaarde (Belgium). Center for Molecular Modeling (CMM); Cottenier, Stefaan [Ghent Univ., Zwijnaarde (Belgium). Center for Molecular Modeling (CMM); Ghent Univ., Zwijnaarde (Belgium). Dept. of Materials Science and Engineering

    2016-07-01

    Polonium isotopes are considered the most hazardous radionuclides produced during the operation of accelerator driven systems (ADS) when lead-bismuth eutectic (LBE) is used as the reactor coolant and as the spallation target material. In this work the use of gold surfaces for capturing polonium from the cover gas of the ADS reactor was studied by thermochromatography. The results show that gaseous monoatomic polonium, formed in dry hydrogen, is adsorbed on gold at 1058 K. Its adsorption enthalpy was calculated as -250±7 kJ mol{sup -1}, using a Monte Carlo simulation code. Highly volatile polonium species that were observed in similar experiments in fused silica columns in the presence of moisture in both inert and reducing gas were not detected in the experiments studying adsorption on gold surfaces. PoO{sub 2} is formed in both dry and moist oxygen, and its interaction with gold is characterized by transport reactions. The interaction of bismuth, present in large amounts in the atmosphere of the ADS, with gold was also evaluated. It was found that bismuth has a higher affinity for gold, compared to polonium, in an inert, reducing, and oxidizing atmosphere. This fact must be considered when using gold as a material for filtering polonium in the cover gas of ADS.

  7. Investigation of evaporation characteristics of polonium and its lighter homologues selenium and tellurium from liquid Pb-Bi-eutecticum

    CERN Document Server

    Neuhausen, J; Eichler, B

    2004-01-01

    The evaporation behaviour of polonium and its lighter homologues selenium and tellurium dissolved in liquid Pb-Bi-eutecticum (LBE) has been studied at various temperatures in the range from 482 K up to 1330 K under Ar/H2 and Ar/H2O-atmospheres using γ-ray spectroscopy. Polonium release in the temperature range of interest for technical applications is slow. Within short term (1h) experiments measurable amounts of polonium are evaporated only at temperatures above 973 K. Long term experiments reveal that a slow evaporation of polonium occurs at temperatures around 873 K resulting in a fractional polonium loss of the melt around 1% per day. Evaporation rates of selenium and tellurium are smaller than those of polonium. The presence of H2O does not enhance the evaporation within the error limits of our experiments. The thermodynamics and possible reaction pathways involved in polonium release from LBE are discussed.

  8. Distribution of polonium-210 in the human lung

    International Nuclear Information System (INIS)

    Cohen, Beverly S.; Eisenbud, Merril; Wrenn, McDonald E.; Harley, Naomi H.

    1978-01-01

    Knowledge of the distribution of 210 Po in the lungs of cigarette smokers is essential if the role of this alpha emitter in smoking related carcinogenesis is to be understood. To resolve this question the tracheobronchial tree is separated from the parenchyma and both are analyzed for 210 Po. Some polonium is cleared to the blood and systemically redistributed. Since systemic distribution should produce the same partition of the nuclide in smokers and nonsmokers, an excess found in either fraction would indicate retention of inhaled 210 Po or its grandparent 210 Pb. We will report the results of these analyses in five smokers and 5 nonsmokers. (author)

  9. The sorption of polonium, actinium and protactinium onto geological materials

    International Nuclear Information System (INIS)

    Baston, G.M.N.; Berry, J.A.; Brownsword, M.; Heath, T.G.; Ilett, D.J.; McCrohon, R.; Tweed, C.J.; Yui, M.

    1999-01-01

    This paper describes a combined experimental and modeling program of generic sorption studies to increase confidence in the performance assessment for a potential high-level radioactive waste repository in Japan. The sorption of polonium, actinium and protactinium onto geological materials has been investigated. Sorption of these radioelements onto bentonite, tuff and granodiorite from equilibrated de-ionized water was studied under reducing conditions at room temperature. In addition, the sorption of actinium and protactinium was investigated at 60 C. Thermodynamic chemical modeling was carried out to aid interpretation of the results

  10. The sorption of polonium, actinium and protactinium onto geological materials

    Energy Technology Data Exchange (ETDEWEB)

    Baston, G.M.N.; Berry, J.A.; Brownsword, M.; Heath, T.G.; Ilett, D.J.; McCrohon, R.; Tweed, C.J.; Yui, M.

    1999-07-01

    This paper describes a combined experimental and modeling program of generic sorption studies to increase confidence in the performance assessment for a potential high-level radioactive waste repository in Japan. The sorption of polonium, actinium and protactinium onto geological materials has been investigated. Sorption of these radioelements onto bentonite, tuff and granodiorite from equilibrated de-ionized water was studied under reducing conditions at room temperature. In addition, the sorption of actinium and protactinium was investigated at 60 C. Thermodynamic chemical modeling was carried out to aid interpretation of the results.

  11. β-delayed charged particle decays of neutron-deficient nuclei 20Mg and 23Si and 22Si

    International Nuclear Information System (INIS)

    Babo, Mathieu

    2016-01-01

    The neutron-deficient nuclei 20 Mg, 23 Si and 22 Si were produced by fragmentation at NSCL, at MSU (USA), and implanted into an array of 3 double sided stripped Si detectors, surrounded by 16 high-purity Ge detectors. This novel arrangement allowed the detection of the charged particles emitted by the unbound excited states in coincidence with the γ rays emitted by the de-excitation of the daughter. The βp decay of 20 Mg is very well-known and therefore was used to test and optimize the analysis program. The β-delayed proton transitions to the first 3 excited states in 19 Ne were identified and compared to previous measurements. The half-life, the branching ratio of the transitions and the excitation energies, including the IAS, were measured and are in good agreement with the adopted values. The study of the β+ decay of 23 Si allowed the identification of 14 excited states in 23 Al. The emission of 2 protons from the IAS was unambiguously identified. The measurement of the IAS energy allowed a better determination of the mass excess of 23 Si, giving 23.27 (7) MeV. A possible β3p decay channel was also tentatively identified. Most of the theoretical predictions are in favor of a 2-proton radioactive 22 Si. The β2p decays to the first excited state and the ground state of 20 Na were identified. The branching ratio of the decay to the IAS is 2.05 (44) %, and the IAS excitation energy was measured to be 9040 (54) keV. The additional measurement of the half-life gives T 1/2 = 30.38 (45) ms, and allowed the determination of the partial half-life. In this study, we propose a parameterization of the statistical rate function f for the superallowed Fermi β decays. This allow the first indirect mass measurement of 22 Si ground state, 31.49 (14) MeV. The two-proton threshold is then S2p = 645 (100) keV and does not allow 2p radioactivity. (author) [fr

  12. Rotation-aligned coupling and axial asymmetry in the neutron deficient lanthanum nuclei. Progress report, May 15, 1975--May 14, 1976

    International Nuclear Information System (INIS)

    Zganjar, E.F.

    1976-01-01

    The work on the neutron deficient nuclei in the Au region was brought nearer to completion, and systems necessary to extend the investigation to the La nuclei were developed. Twelve reports, including five journals articles, were generated during the reporting period, and the principal investigator received invitations to two international conferences. The LSU nuclear spectroscopy group was given a good deal of support and added strength (by the Department of Physics and Astronomy) through the addition of a nuclear structure theorist and a departmentally sponsored postdoctoral position

  13. Mass measurement of cooled neutron-deficient bismuth projectile fragments with time-resolved Schottky mass spectrometry at the FRS-ESR facility

    Energy Technology Data Exchange (ETDEWEB)

    Litvinov, Yu.A.; Geissel, H. [Giessen Univ. (Germany); Radon, T. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (DE)] [and others

    2005-06-01

    Masses of 582 neutron-deficient nuclides (30{<=}Z{<=}85) were measured with time-resolved Schottky mass spectrometry at the FRS-ESR facility at GSI, 117 were used for calibration. The masses of 71 nuclides were obtained for the first time. A typical mass accuracy of 30 {mu}u was achieved. These data have entered the latest atomic mass evaluation. The mass determination of about 140 additional nuclides was possible via known energies (Q-values) of {alpha}-, {beta}-, or proton decays. The obtained results are compared with the results of other measurements. (orig.)

  14. Bioaccumulation of polonium 210Po in marine birds

    International Nuclear Information System (INIS)

    Skwarzec, B.; Fabisiak, J.

    2007-01-01

    The aim of this work was to determine the 210 Po content in marine birds which permanently or temporally live in the Polish part of the Baltic Sea. We chose 11 species of sea birds: three species permanently residing at southern Baltic Sea, four species of wintering birds and three species of migrating birds. The results show that the polonium is non-uniformly distributed in the marine birds. The highest activities of 210 Po were observed in feathers, muscles and liver and the lowest in skin and skeleton. Species of birds that eat crustaceans, molluscs, fish and plants (long-tailed duck Clangula hyemalis, white-winged scoter Melanitta fusca) accumulated more polonium than species that eat mainly fish (great cormorant Phalacrocorax carbo, common guillemot Uria aalge) or plants (tufted duck Aythya fuligula). Moreover, about 63% of the 210 Po that was located in feathers of razorbil (Alca torda) and long-tailed duck (C. hyemalis) was apparently adsorbed, suggesting an external source such as the air. It means that the adsorption of 210 Po on the feather surface may be an important transfer from air to water

  15. Human absorption and retention of polonium-210 from caribou meat.

    Science.gov (United States)

    Thomas, P A; Fisenne, I; Chorney, D; Baweja, A S; Tracy, B L

    2001-01-01

    The gastrointestinal (GI) absorption factors and the biological retention times for polonium were determined for a group of 14 volunteers--seven men and seven women--from Saskatoon, Saskatchewan, Canada. Each volunteer consumed 2.0 kg of caribou meat containing known amounts of naturally occurring 210Po. Urine and faecal samples were collected for up to 65 days after meat consumption and analysed for 210Po. The average GI absorption factor for the 14 volunteers was 56 +/- 4% (range = 31-71%), not significantly different from the ICRP value of 50%. About 3% of absorbed polonium underwent prompt excretion by the urinary pathway. The remainder was retained by the body with a half-time >100 days, compared to the ICRP value of 50 days. The effect of these findings increases the dose estimate for ingestion of 210Po in food by a factor of 1.5 to 3.5. Thus, background doses to people consuming caribou and reindeer may be higher than previously thought.

  16. Human absorption and retention of polonium-210 from caribou meat

    International Nuclear Information System (INIS)

    Thomas, P.A.; Fisenne, I.; Chorney, D.; Baweja, A.S.; Tracy, B.L.

    2001-01-01

    The gastrointestinal (GI) absorption factors and the biological retention times for polonium were determined for a group of 14 volunteers - seven men and seven women - from Saskatoon, Saskatchewan, Canada. Each volunteer consumed 2.0 kg of caribou meat containing known amounts of naturally occurring 210 Po. Urine and faecal samples were collected for up to 65 days after meat consumption and analysed for 210 Po. The average GI absorption factor for the 14 volunteers was 56±4% (range = 31-71%), not significantly different from the ICRP value of 50%. About 3% of absorbed polonium underwent prompt excretion by the urinary pathway. The remainder was retained by the body with a half-time >100 days, compared to the ICRP value of 50 days. The effect of these findings increases the dose estimate for ingestion of 210 Po in food by a factor of 1.5 to 3.5. Thus, background doses to people consuming caribou and reindeer may be higher than previously thought. (author)

  17. Pathways for the release of polonium from a lead-bismuth spallation target (thermochemical calculation); Verfluechtigungspfade des Poloniums aus einem Pb-Bi-Spallationstarget (Thermochemische Kalkulation)

    Energy Technology Data Exchange (ETDEWEB)

    Eichler, B.; Neuhausen, J

    2004-06-01

    An analysis of literature data for the thermochemical constants of polonium reveals considerable discrepancies in the relations of these data among each other as well as in their expected trends within the chalcogen group. This fact hinders a reliable assessment of possible reaction paths for the release of polonium from a liquid lead-bismuth spallation target. In this work an attempt is made to construct a coherent data set for the thermochemical properties of polonium and some of its compounds that are of particular importance with respect to the behaviour of polonium in a liquid Pb-Bi target. This data set is based on extrapolations using general trends throughout the periodic table and, in particular, within the chalcogen group. Consequently, no high accuracy should be attributed to the derived data set. However, the data set derived in this work is consistent with definitely known experimental data. Furthermore, it complies with the general trends of physicochemical properties within the chalcogen group. Finally, well known relations between thermochemical quantities are fulfilled by the data derived in this work. Thus, given the lack of accurate experimental data it can be regarded as best available data. Thermochemical constants of polonium hydride, lead polonide and polonium dioxide are derived based on extrapolative procedures. Furthermore, the possibility of formation of the gaseous intermetallic molecule BiPo, which has been omitted from discussion up to now, is investigated. From the derived thermochemical data the equilibrium constants of formation, release and dissociation reactions are calculated for different polonium containing species. Furthermore equilibrium constants are determined for the reaction of lead polonide and polonium dioxide with hydrogen, water vapour and the target components lead and bismuth. The most probable release pathways are discussed. From thermochemical evaluations polonium is expected to be released from liquid lead

  18. Study of polonium-210 in tobacco in Tunisia

    International Nuclear Information System (INIS)

    Rahali, Saifeddine

    2014-01-01

    Polonium-210 is a radio-isotopes natural α emitter, it cans be found in tobacco with a significant range. The high activity of 210 Po in tobacco and cigarettes causes the absorption of a high dose of alpha radiation that caused probably lung cancer, the objective of this study is to estimate the activity of 210 Po in tobacco matrix. Thirteen samples of cigarettes consumed in tunisia were experimented to determine the activity of this radionuclide. The PIPS, a silicon semiconductor, is used as on α spectrometry detector for the detection of 210 Po in all of our samples. The final results showed a high radioactivity of 210 Po from 11.77 to 25.31 mBq/g. We conclude that the effective annual average is estimated at 106.53 μSv / year.

  19. Polonium in mainstream cigarette smoke and associated internal radiation dose

    International Nuclear Information System (INIS)

    Tiwari, M.; Rathod, T.D.; Bhangare, R.C.; Ajmal, P.Y.; Maity, S.; Sahu, S.K.; Pandit, G.G.

    2015-01-01

    210 Po activity concentrations in cigarettes tobacco, mainstream cigarette smoke (MCS), ash and post smoking filter were measured by alpha spectrometry using surface barrier detectors, following the radiochemical separation of polonium. The results of present study indicate that the average (range) activity concentration of 210 Po in cigarette tobacco were 9.77 to 15.34 mBq per cigarette. The combined annual effective doses due to internal exposure of 210 Po and 210 Pb for a smoker (considering on an average 20 cigarette a day and 50% of MCS getting deposited in respiratory tract) were found to be ranging from 0.28 to 0.40 mSv for tested brands of cigarette. (author)

  20. Radiological Dispersal Polonium-210, and Lessons for Public Health

    International Nuclear Information System (INIS)

    Whitcomb, R. C.; Miller, C. W.

    2007-01-01

    On November 23, 2006, Alexander Litvinenko died in London as a result of being poisoned with Polonium-210. Public health authorities in the United Kingdom (UK) subsequently found Polonium-210 contamination at a number of locations in and around London. UK authorities have determined that citizens of 48 countries other than the UK, including the United States, may have been exposed to this contamination. UK authorities asked the CDC to contact approximately 160 individuals who may have been exposed to Po-210. These citizens have been advised that their risk of adverse health effects is likely to be low, but, if they are concerned, they should contact their primary health care provider. In turn, physicians are referred to state and local public health departments or CDC for further information on Po-210, including where they can seek testing of 24 hour urine samples for Po-210, if desired. CDC posted guidance for members of the public and physicians on its web site, and it responded to numerous inquiries from national media. Working with our UK colleagues, CDC developed guidelines for judging when a measurement of Po-210 in urine was or was not a level of concern. Because the death of Mr. Litvinenko is an ongoing criminal investigation, one of the major challenges of this response to what is a radiological dispersal device event has been the inability to obtain all of the technical detail desired to perform assessments. This has complicated the ability to communicate effectively with citizens and members of the public health community. These and other lessons learned from this response will help prepare the public health community to respond more effectively to future contamination events involving radioactive dispersal in the environment.(author)

  1. Investigation of electrostatic collection of some polonium radioisotopes for plane and hemispheric geometries

    International Nuclear Information System (INIS)

    Lobach, D.J.; Dezhurko, M.D.

    2004-01-01

    The model approach to the description of the electrostatic collection (precipitation) of short-lived radon daughter products (RDP) is presented. The considerations are based on speculations about current processes (oxidation ( k - the constant of polonium oxidation), recombination (α - the constant of recombination), neutralization (γ - the constant of polonium oxide neutralization) and radioactive decay (λ - the constant of radioactive decay)). The subscript Rn refers to radon; Po, to polonium ( 215 Po, 216 Po, 218 Po); PoO, to polonium oxide (PoO 2 ). There is continuous uniform ionization in working matter of plane electrostatic chamber for RDP collection (the length of the chamber is d). The formation intensity of ion pairs is q, which is in correlation to the volume activity (VA) of radioactive ions in the chamber and irradiation from external sources. It is neglected by ion diffusion during electrostatic collection. Recombination losses are from collisions of heavy ions solely. Positive ions are collected on the working surface of the detector (cathode of the electrostatic chamber). n ± is the volume concentration of positive (negative) ions; ω ± > 0 is the drift velocity of positive (negative) ions. The driftage of positive ions along x-axis (to the cathode) and the balance of ions in dx layer are considered. At k approaching infinity, k >> λ Po + αn - and it is possible to obtain a single expression for the two polonium fractions: ω +PoO (dn +PoO /dx) = λ Rn n Rn - α n +PoO n - - γ n +PoO - λ Po n +PoO . The driftage time of positive ions in plane electrostatic chamber should be τ(drift) = d/ω + PoO is the mobility of polonium ions or aerosol complexes with polonium: ε(U) = [(μ PoO . U)/(d 2 . (λ Po + γ))] . [1 - exp [(d 2 . (λ Po + γ))/(μ PoO . U)

  2. Performance of the multiple target He/PbI sub 2 aerosol jet system for mass separation of neutron-deficient actinide isotopes

    CERN Document Server

    Ichikawa, S; Asai, M; Haba, H; Sakama, M; Kojima, Y; Shibata, M; Nagame, Y; Oura, Y; Kawade, K

    2002-01-01

    A multiple target He/PbI sub 2 aerosol jet system coupled with a thermal ion source was installed in the isotope separator on line (JAERI-ISOL) at the JAERI tandem accelerator facility. The neutron-deficient americium and curium isotopes produced in the sup 2 sup 3 sup 3 sup , sup 2 sup 3 sup 5 U( sup 6 Li, xn) and sup 2 sup 3 sup 7 Np( sup 6 Li, xn) reactions were successfully mass-separated and the overall efficiency including the ionization of Am atoms was evaluated to be 0.3-0.4%. The identification of a new isotope sup 2 sup 3 sup 7 Cm with the present system is reported.

  3. Shape coexistence in neutron-deficient Hg isotopes studied via lifetime measurements in $^{184,186}$Hg and two-state mixing calculations

    CERN Document Server

    Gaffney, L P; Page, R.D.; Grahn, T.; Scheck, M.; Butler, P.A.; Bertone, P.F.; Bree, N.; Carroll, R.J.; Carpenter, M.P.; Chiara, C.J.; Dewald, A.; Filmer, F.; Fransen, C.; Huyse, M.; Janssens, R.V.F.; Joss, D.T.; Julin, R.; Kondev, F.G.; Nieminen, P.; Pakarinen, J.; Rigby, S.V.; Rother, W.; Van Duppen, P.; Watkins, H.V.; Wrzosek-Lipska, K.; Zhu, S.

    2014-01-01

    The neutron-deficient mercury isotopes, $^{184,186}$Hg, were studied with the Recoil Distance Doppler Shift (RDDS) method using the Gammasphere array and the K\\"oln Plunger device. The Differential Decay Curve Method (DDCM) was employed to determine the lifetimes of the yrast states in $^{184,186}$Hg. An improvement on previously measured values of yrast states up to $8^{+}$ is presented as well as first values for the $9_{3}$ state in $^{184}$Hg and $10^{+}$ state in $^{186}$Hg. $B(E2)$ values are calculated and compared to a two-state mixing model which utilizes the variable moment of inertia (VMI) model, allowing for extraction of spin-dependent mixing strengths and amplitudes.

  4. Polonium in cigarette smoke and radiation exposure of lungs

    International Nuclear Information System (INIS)

    Carvalho, F.P.; Oliveira, J.M.

    2006-01-01

    210 Po was analysed in three common brands of cigarettes produced in Portugal. The analyses of polonium were performed using 209 Po as an internal isotopic tracer. Samples were dissolved with acids, polonium plated on a silver disc and measured by alpha spectrometry using silicon surface barrier detectors. The analyses were carried out on the unburned tobacco contained in the cigarettes, on the ashes of smoked cigarettes and on the mainstream smoke inhaled by the smoker. 210 Po in the tobacco display concentrations ranging from 3 to 37 mBq/g, depending upon the cigarette brand. The 210 Po remaining in the solid residue of a smoked cigarette varied between 0.3 to 4.9 mBq per cigarette, and the 210 Po in the inhaled smoke from one cigarette varied from 2.6 to 28.9 mBq. In all brands of cigarettes tested, about 50 % of the 210 Po content is not inhaled by the smoker and it is released into the atmosphere. Part of it may be inhaled by passive smokers. Depending upon the commercial brand and upon the presence or absence of a filter in the cigarette, 5 to 37 % of the 210 Po in the cigarette can be inhaled by the smoker. Taking into account the average 210 Po and 210 Pb in surface air, the smoker of one pack of twenty cigarettes per day may inhale 50 times more 210 Po than a non smoker. The average absorption of 210 Po into the blood taking all pathways into account is 0.39 Bq d -1 . This includes, namely, the ingestion of water and beverages, the ingestion of food, the inhalation of air and cigarette smoke. Cigarette smoke contributes with 1.5 % to this rate of 210 Po absorption into the blood and, after circulating in all organs, gives rise to a whole body radiation dose in the same proportion. However, in the smoker the deposition of 210 Po in the lungs is much more elevated than normal and may originate an enhanced radiation exposure of this organ. Estimated dose to the lungs is presented and radiobiological effects of cigarette smoking are discussed. (author)

  5. Ab initio study of the trapping of polonium on noble metals

    Science.gov (United States)

    Rijpstra, Kim; Van Yperen-De Deyne, Andy; Maugeri, Emilio Andrea; Neuhausen, Jörg; Waroquier, Michel; Van Speybroeck, Veronique; Cottenier, Stefaan

    2016-04-01

    In the future MYRRHA reactor, lead bismuth eutectic (LBE) will be used both as coolant and as spallation target. Due to the high neutron flux a small fraction of the bismuth will transmute to radiotoxic 210Po. Part of this radiotoxic element will evaporate into the gas above the coolant. Extracting it from the gas phase is necessary to ensure a safe handling of the reactor. An issue in the development of suitable filters is the lack of accurate knowledge on the chemical interaction between a candidate filter material and either elemental polonium or polonium containing molecules. Experimental work on this topic is complicated by the high radiotoxicity of polonium. Therefore, we present in this paper a first-principles study on the adsorption of polonium on noble metals as filter materials. The adsorption of monoatomic Po is considered on the candidate filter materials palladium, platinum, silver and gold. The case of the gold filter is looked upon in more detail by examining how bismuth pollution affects its capability to capture polonium and by studying the adsorption of the heavy diatomic molecules Po2, PoBi and PoPb on this gold filter.

  6. A study on optimum conditions for reducing Polonium-210 ion in electrolysis process

    International Nuclear Information System (INIS)

    Yii Mei Wo

    2006-01-01

    Polonium-210 is one of the most important radionuclide to be study while studying radioactive contaminants on marine lives. It usually be self-deposited on a pure silver foil and counted using an Alpha Spectrometry System. However, using pure silver foil involves high cost. Therefore, study had been conducted to find the suitability of using stainless steel disc to deposit polonium-210 using electrolysis process and the optimum conditions for such process. This was carry out by using pure polonium-210 standard solution and the ready disc was counted using Zinc Sulphite Counter. Results show that reduction of polonium ion on stainless steel disc can be done but the efficiency of the process only around 70 percent. Besides this, studies also show that, at 1.1 ampere constant current and cathode to anode distance at 8 mm, the optimum conditions to reduce polonium ion were at pH 2.2-2.3 with the electrolysis time of 5 hours. (Author)

  7. Ab initio study of the trapping of polonium on noble metals

    Energy Technology Data Exchange (ETDEWEB)

    Rijpstra, Kim; Van Yperen-De Deyne, Andy [Center for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Ghent (Belgium); Maugeri, Emilio Andrea; Neuhausen, Jörg [Laboratory for Radiochemistry, Paul Scherrer Institute (PSI), 5232 Villigen (Switzerland); Waroquier, Michel; Van Speybroeck, Veronique [Center for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Ghent (Belgium); Cottenier, Stefaan, E-mail: stefaan.cottenier@ugent.be [Center for Molecular Modeling (CMM), Ghent University, Technologiepark 903, 9052 Ghent (Belgium); Department of Materials Science and Engineering, Ghent University, Technologiepark 903, 9052 Ghent (Belgium)

    2016-04-15

    In the future MYRRHA reactor, lead bismuth eutectic (LBE) will be used both as coolant and as spallation target. Due to the high neutron flux a small fraction of the bismuth will transmute to radiotoxic {sup 210}Po. Part of this radiotoxic element will evaporate into the gas above the coolant. Extracting it from the gas phase is necessary to ensure a safe handling of the reactor. An issue in the development of suitable filters is the lack of accurate knowledge on the chemical interaction between a candidate filter material and either elemental polonium or polonium containing molecules. Experimental work on this topic is complicated by the high radiotoxicity of polonium. Therefore, we present in this paper a first-principles study on the adsorption of polonium on noble metals as filter materials. The adsorption of monoatomic Po is considered on the candidate filter materials palladium, platinum, silver and gold. The case of the gold filter is looked upon in more detail by examining how bismuth pollution affects its capability to capture polonium and by studying the adsorption of the heavy diatomic molecules Po{sub 2}, PoBi and PoPb on this gold filter.

  8. A study of polonium-210 distribution in Syrian phosphogypsum and its leaching mechanisms

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Al-Bich, F.

    2000-02-01

    Polonium 210 distribution in Syrian phosphogypsum and its leaching mechanisms have been evaluated. Radiochemical analysis have shown that 210 Po concentration in Syrian phosphogypsum is always higher than 226 Po concentrations were found to vary between 373 and 589 Bq.Kg -1 with an average value of 471 Bq.Kg -1 , which is lower than those values reported in other countries. 210 Po was found to be more enhanced in smaller particles; a specific activities of 827 Bq.Kg -1 in particles with size less than 250 mesh being observed. Leaching experiments using distilled water have shown that 210 are strongly bounded to phosphogypsum particles. The amount of 210 Po transferred to aqueous media does not exceed 5.6% and 8.4% for batch wise and continuous leaching respectively; lowering the ph has increased this percentage to 20%. In addition, leaching with diluted sulfuric acid indicated that 80% of polonium is present as water insoluble quadrivalent polonium sulphate while 20% as soluble simple polonium sulfate (2PoO 2 .So 3 ). While leaching with selective agents such as MgCl 2 and NH 4 AC have shown that 58% of polonium is present on the surface of gypsum lattice. However, the obtained data could be used to explain environmental pathway of 210 Po from phosphogypsum. (Author)

  9. Review of chemical and radiotoxicological properties of polonium for internal contamination purposes.

    Science.gov (United States)

    Ansoborlo, Eric; Berard, Philippe; Den Auwer, Christophe; Leggett, Rich; Menetrier, Florence; Younes, Ali; Montavon, Gilles; Moisy, Philippe

    2012-08-20

    The discovery of polonium (Po) was first published in July, 1898 by P. Curie and M. Curie. It was the first element to be discovered by the radiochemical method. Polonium can be considered as a famous but neglected element: only a few studies of polonium chemistry have been published, mostly between 1950 and 1990. The recent (2006) event in which (210)Po evidently was used as a poison to kill A. Litvinenko has raised new interest in polonium. 2011 being the 100th anniversary of the Marie Curie Nobel Prize in Chemistry, the aim of this review is to look at the several aspects of polonium linked to its chemical properties and its radiotoxicity, including (i) its radiochemistry and interaction with matter; (ii) its main sources and uses; (iii) its physicochemical properties; (iv) its main analytical methods; (v) its background exposure risk in water, food, and other environmental media; (vi) its biokinetics and distribution following inhalation, ingestion, and wound contamination; (vii) its dosimetry; and (viii) treatments available (decorporation) in case of internal contamination.

  10. Determination of the polonium-210 content in the urine of Filipino smokers and non-smokers

    International Nuclear Information System (INIS)

    Juan, N.B.; Ballelos, E.; Bartolome, Z.M.

    1975-01-01

    Presence of polonium in tobacco poses a health hazard to smokers. Polonium is a pure alpha emitter with an energy of 5.3 MeV decaying with a half-life 138.4 days to a stable isotope of lead. The polonium content in the urine of Filipino smokers was compared with that of non-smokers. The polonium was recovered from urine by centrifugation and deposition into silver discs. Quantitative results were obtained by counting the silver discs using a silicon surface-barrier detector. The average value obtained for smokers which was 0.5003+-0.2988 pCi/24h sample was significantly higher than the value obtained for non-smokers which was 0.2313+-0.1664 pCi/24h sample. The efficiency of the procedure employed encourages the use of urinalysis as a measure of the polonium body burden and also as a rough index of the dose absorbed from radium or any of its daughters

  11. Large deficiency of polonium in the oligotrophic ocean's interior

    Science.gov (United States)

    Kim, Guebuem

    2001-09-01

    The naturally occurring radionuclide 210Po is typically deficient relative to its parent 210Pb in the surface ocean due to preferential removal by biota, while in near equilibrium or excess below the surface mixed layer due to rapid regeneration from sinking organic matter. However, a strikingly large deficit of 210Po is observed in the oligotrophic Sargasso Sea's interior. This argues against the general concept that the removal of reactive elements depends on the population of settling particles. A 210Po mass balance model suggests that rather than downward transport, polonium (proxy for S, Se, and Te) is taken up efficiently by bacteria (i.e., cyanobacteria) and transferred to higher trophic levels (i.e., nekton) in this environment. In contrast, in productive areas of the ocean, sulfur group elements seem to reside in the subsurface ocean for much longer periods as taken up by abundant free-living bacteria (non-sinking fine particles). This study sheds new light on global biogeochemical cycling of sulfur group elements in association with microbial roles, and suggests that 210Po may be useful as a tracer of nitrogen fixation in the ocean.

  12. Transfer factors of Polonium from soil to parsley and mint

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Al-Hamwi, A.; Eadan, Z.; Amin, Y.

    2010-01-01

    Transfer factors of 210 Po from soil to parsley and mint have been determined. Artificial polonium isotope ( 208 Po) was used as a tracer to determine transfer factor of Po from soil to plant in pot experiments. Two plant growing systems were used for this study namely, an outdoor system and a sheltered system by a polyethylene tent. 208 Po and 210 Po were determined in soil and different parts of the studied plants (stem and leaf), using alpha spectroscopy. The results have shown that there was a clear uptake of 208 Po by roots to leaves and stems of both plants. Higher values of transfer factors using the 210 Po activity concentrations than the 208 Po activity concentration were observed. Transfer factors of 210 Po from soil to parsley varied between 20 x 10 -2 and 50 x 10 -2 and 22 x 10 -3 and 67 x 10 -3 in mint, while 208 Po transfer factors varied between 4 x 10 -2 and 12 x 10 -2 for parsley and 10 x 10 -2 and 22 x 10 -2 in mint. Transfer factors of Po were higher in those plants grown in the sheltered system than in the open system; about 75% of Po was transferred from atmosphere to parsley parts using the two systems. Ratios of transferred Po from soil to mint stem and leaf in the sheltered system were higher by 2 times from those in the open system.

  13. Polonium-210 in the environment around a radioactive waste disposal area and phosphate ore processing plant

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, III, W J; Markham, O D

    1984-04-01

    Polonium-210 concentrations were determined for soil, vegetation and small mammal tissues collected at a solid radioactive waste disposal area, near a phosphate ore processing plant and at two rural areas in southeastern Idaho. Polonium concentrations in media sampled near the radioactive waste disposal facility were equal to or less than values from rural area samples, indicating that disposal of solid radioactive waste at the Idaho National Engineering Laboratory Site has not resulted in increased environmental levels of polonium. Concentrations of /sup 210/Po in soils, deer mice hide and carcass samples collected near the phosphate processing plant were statistically greater than the other sampling locations; however, the mean /sup 210/Po concentration in soils and small mammal tissues from sampling areas near the phosphate plant were only four and three times greater, respectively, than control values. No statistical difference was observed for /sup 210/Po concentrations in vegetation among any of the sampling locations.

  14. Effect of polonium alpha-radiation on aqueous solutions (the history of French and Russian studies)

    International Nuclear Information System (INIS)

    Vladimirova, M.V.

    1998-01-01

    Since Pierre and Marie Curie's discovery of polonium and radium the effect of their radiation on chemical systems was noted. This gave rise to a new science - radiation chemistry. Systematic studies of radiation effects go back to the mid-1940s. The effect of gamma and x radiation was studied most, while only M. Curie's laboratory in France was concerned with alpha emitting polonium and radon. M. Haissinsky, M. Lefort, P. Bonet-Marry, M. Anta pioneered this activity. Radon was soon abandoned in favour of polonium recovered from RaD. With its short half-life, polonium is an ideal emitter which at its low content by weight produces a highly intensive radiation. French scientists determined radiation yields of H 2 , O 2 , H 2 O 2 and that of water radiolytic decomposition, G[-H 2 O]. The latter was found to be equal to 3.5 molecule/100 eV and much less than that from gamma radiolysis (4.2 molecule/100 eV). It should be noted that the polonium recovered from RaD contained a variety of impurities influencing the yield of radiolysis products formed. From the outset of her study in 1957, the author of this paper used the purest polonium recovered from reactor-irradiated Bi-209. This made it possible to define the yields from alpha radiolysis of various aqueous solutions more exactly. Relying on the J. Pucheault hypothesis concerning the decomposition of molecular radiolysis products in heavy particle tracks, author's efforts were directed toward the quantification of initial radiolysis yields. Special experiments have shown that G[-H 2 O] is much the same from alpha and gamma radiolysis (around 4.2 molecule/100eV). The author had the good luck to discuss her results with Pr. M. Haissinsky from Laboratory Curie. (author)

  15. Determination of polonium-210 levels in some syrian soils and crops

    International Nuclear Information System (INIS)

    Othman, I.; Al-Masri, M.S.; Aba, A.A.; Mukhallaty, H.; Al-Hamwy, A.; Khalili, H.

    1997-04-01

    Polonium 210 levels in the edible port of 19 agricultural crops collected from ten locations in Syria have been determined. Results have been shown that the highest concentrations were found to be in parsley (10.49 Bq/Kg) and this due to high area of its levels. Moreover, the concentrations were low in some vegetables such as tomatoes (0.2 Bq/Kg). In addition, polonium 210 was also determined in Syria soil where it was found to vary between 20 Bq/Kg and 68.8 Bq/Kg). (author). 11 refs., 17 tabs

  16. Transfer factors of polonium from soil to parsley and mint.

    Science.gov (United States)

    Al-Masri, M S; Al-Hamwi, A; Eadan, Z; Amin, Y

    2010-12-01

    Transfer factors of (210)Po from soil to parsley and mint have been determined. Artificial polonium isotope ((208)Po) was used as a tracer to determine transfer factor of Po from soil to plant in pot experiments. Two plant growing systems were used for this study namely, an outdoor system and a sheltered system by a polyethylene tent. (208)Po and (210)Po were determined in soil and different parts of the studied plants (stem and leaf), using alpha spectroscopy. The results have shown that there was a clear uptake of (208)Po by roots to leaves and stems of both plants. Higher values of transfer factors using the (210)Po activity concentrations than the (208)Po activity concentration were observed. Transfer factors of (210)Po from soil to parsley varied between 20 × 10⁻² and 50 × 10⁻² and 22 × 10⁻³ and 67 × 10⁻³ in mint, while (208)Po transfer factors varied between 4 × 10⁻² and 12 × 10⁻² for parsley and 10 × 10⁻² and 22 × 10⁻² in mint. Transfer factors of Po were higher in those plants grown in the sheltered system than in the open system; about 75% of Po was transferred from atmosphere to parsley parts using the two systems. Ratios of transferred Po from soil to mint stem and leaf in the sheltered system were higher by 2 times from those in the open system. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. Transfer factors of Polonium from soil to parsley and mint

    Energy Technology Data Exchange (ETDEWEB)

    Al-Masri, M.S., E-mail: prscientific@aec.org.s [Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091 (Syrian Arab Republic); Al-Hamwi, A. [Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091 (Syrian Arab Republic); Eadan, Z. [Physics Department, Damascus University (Syrian Arab Republic); Amin, Y. [Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, P.O. Box 6091 (Syrian Arab Republic)

    2010-12-15

    Transfer factors of {sup 210}Po from soil to parsley and mint have been determined. Artificial polonium isotope ({sup 208}Po) was used as a tracer to determine transfer factor of Po from soil to plant in pot experiments. Two plant growing systems were used for this study namely, an outdoor system and a sheltered system by a polyethylene tent. {sup 208}Po and {sup 210}Po were determined in soil and different parts of the studied plants (stem and leaf), using alpha spectroscopy. The results have shown that there was a clear uptake of {sup 208}Po by roots to leaves and stems of both plants. Higher values of transfer factors using the {sup 210}Po activity concentrations than the {sup 208}Po activity concentration were observed. Transfer factors of {sup 210}Po from soil to parsley varied between 20 x 10{sup -2} and 50 x 10{sup -2} and 22 x 10{sup -3} and 67 x 10{sup -3} in mint, while {sup 208}Po transfer factors varied between 4 x 10{sup -2} and 12 x 10{sup -2} for parsley and 10 x 10{sup -2} and 22 x 10{sup -2} in mint. Transfer factors of Po were higher in those plants grown in the sheltered system than in the open system; about 75% of Po was transferred from atmosphere to parsley parts using the two systems. Ratios of transferred Po from soil to mint stem and leaf in the sheltered system were higher by 2 times from those in the open system.

  18. Polonium in cigarette smoke and radiation exposure of lungs

    International Nuclear Information System (INIS)

    Carvalho, F.P.; Oliveira, J.M.

    2006-01-01

    Polonium ( 210 Po), the most volatile of naturally-occurring radionuclides in plants, was analysed in three common brands of cigarettes produced in Portugal. The analyses were carried out on the unburned tobacco contained in cigarettes, on the ashes and butts of smoked cigarettes and on the mainstream smoke. 210 Po in tobacco displays concentrations ranging from 3 to 37 mBq g -1 , depending upon the cigarette brand. The 210 Po activity remaining in the solid residue of a smoked cigarette varied from 0.3 to 4.9 mBq per cigarette, and the 210 Po in the inhaled smoke varied from 2.6 to 28.9 mBq. In all brands of cigarettes tested, a large fraction of the 210 Po content is not inhaled by the smoker and it is released into the atmosphere. Part of it may be inhaled by passive smokers. Depending upon the commercial brand and upon the presence or absence of a filter in the cigarette, 5 to 37 % of the 210 Po in the cigarette can be inhaled by the smoker. Taking into account the average 210 Po in surface air, the smoker of one pack of twenty cigarettes per day may inhale 50 times more 210 Po than a non smoker. Cigarette smoke contributes with 1.5 % to the daily rate of 210 Po absorption into the blood, 0.39 Bq d -1 , and, after systemic circulation it gives rise to a whole body radiation dose in the same proportion. However, in the smoker the deposition of 210 Po in the lungs is much more elevated than normal and may originate an enhanced radiation exposure. Estimated dose to the lungs is presented and radiobiological effects of cigarette smoke are discussed. (author)

  19. Dosimetric consideration of polonium-210 for Tiruchirappalli public

    International Nuclear Information System (INIS)

    Shaheed, K.; Somasundaram, S.S.N.; Shahul Hameed, P.

    1997-01-01

    This paper deals with the committed effective dose equivalent from polonium-210 to the public of Tiruchirappalli district in south India on consumption of cereals, vegetables and animal food. It is demonstrated that the activity of 210 Po is non-uniformly distributed between cereals, vegetables and animal food. Among cereals, the green gram recorded a higher activity of 210 Po (0.62 Bq.kg -1 ) than the others tested. The study also recorded a relatively enhanced activity in raw rice (0.90 Bq.kg -1 ) than in boiled rice (0.03 Bq.kg -1 ). Among vegetables, the tubers accumulated more 210 Po than the shoot growing vegetables. The muscle of prawn (Macrobrachium rosenbergii) recorded the highest level of 210 Po activity (13.9 Bq.kg -1 ) among the animal food. With reference to dosimetry, the animal food was identified to contribute higher radiation dose (0.38-29.5 μSv.y -1 ) than the cereals (0.05 - 1.9 μSv.y -1 ) and vegetables (0.05 - 1.9 μSv.y -1 ). Among animal food, the fish contributed a substantial level of α radiation dose to man. Though activity in raw rice was higher than the activity in boiled rice, the dose delivered from raw rice was substantially low since the average consumption of this rice represents only 7 kg.y -1 when compared to the consumption of boiled rice (108 kg.y -1 ). From the dose estimates made, it was evident that the total dose received by the general public (2.7 μSv.y -1 ) from 210 Po was well below the dose limit of 1mSv.y -1 . (author)

  20. Radiocesium and polonium in seals from the Baltic Sea. A preliminary study; Radiocaesium och polonium i sael fran Oestersjoen, en preliminaer studie

    Energy Technology Data Exchange (ETDEWEB)

    Holm, E. [Risoe National Lab., Roskilde (Denmark); Leisvik, M. [Lunds Univ., Avd. foer Radiofysik, Lund (Sweden)

    2002-04-01

    {sup 137}Cs and {sup 210}Po in muscle, liver and kidney from 5 seals from the Baltic Sea have been studied. Assuming that the seals consume 5% of their own body weight each day and by using previously obtained data for the doses in fish, the biological half time has been estimated to 20 days for Cesium and 35 days for Polonium. The maximum yearly doses are calculated to 76 {mu}Gy from {sup 137}CS to muscle and 3 500 {mu}Gy to kidneys from {sup 210}Po. These data are very preliminary, the number of individuals being so small, and it is difficult to estimate how much food other than fish the seals consume. Furthermore only few data for radioactive concentrations in whole fish exist, which especially impacts the results for Polonium. (LN)

  1. Penning-trap mass spectrometry and mean-field study of nuclear shape coexistence in the neutron-deficient lead region

    Science.gov (United States)

    Manea, V.; Ascher, P.; Atanasov, D.; Barzakh, A. E.; Beck, D.; Blaum, K.; Borgmann, Ch.; Breitenfeldt, M.; Cakirli, R. B.; Cocolios, T. E.; Day Goodacre, T.; Fedorov, D. V.; Fedosseev, V. N.; George, S.; Herfurth, F.; Kowalska, M.; Kreim, S.; Litvinov, Yu. A.; Lunney, D.; Marsh, B.; Neidherr, D.; Rosenbusch, M.; Rossel, R. E.; Rothe, S.; Schweikhard, L.; Wienholtz, F.; Wolf, R. N.; Zuber, K.

    2017-05-01

    We present a study of nuclear shape coexistence in the region of neutron-deficient lead isotopes. The midshell gold isotopes 180,185,188,190Au (Z =79 ), the two long-lived nuclear states in 197At (Z =85 ), and the neutron-rich nuclide 219At were produced by the ISOLDE facility at CERN and their masses were determined with the high-precision Penning-trap mass spectrometer ISOLTRAP. The studied gold isotopes address the trend of binding energies in a region of the nuclear chart where the nuclear charge radii show pronounced discontinuities. Significant deviations from the atomic-mass evaluation were found for Au,190188. The new trend of two-neutron separation energies is smoother, although it does reveal the onset of deformation. The origin of this effect is interpreted in connection to the odd-even staggering of binding energies, as well as theoretically by Hartree-Fock-Bogoliubov calculations including quasiparticle blocking. The role of blocking for reproducing the large odd-even staggering of charge radii in the mercury isotopic chain is illustrated.

  2. Gamma spectroscopic studies of the neutron-deficient g-g nucleus 74Kr by means of a neutron multiplicity measurement technique

    International Nuclear Information System (INIS)

    Roth, J.

    1981-01-01

    The g-g nucleus 74 Kr was studied by means of the reaction 58 Ni ( 19 F, p2n#betta#) 74 Kr. In order to make gamma spectroscopic studies at neutron deficient nuclei like 74 Kr a neutron multiplicity measurement technique was developed. Beside #betta# single spectra, #betta# excitation functions, #betta#-#betta# coincidences, #betta# angular distributions, and lifetime measurements by means of this technique all measurements in coincidence with up to two neutrons were taken up. From these measurement data an extended term scheme with 17 newly found excited states could be extracted. To all levels spins and parities could be assigned. From the four energetically lowest levels of the yrast cascade the mean lifetimes could be determined. A double backbending in the sequence of the yrast cascade was interpreted as crossing of the g 9/2 bands. The irregularities in the lower part of the yrast band correspond to the shape consistence picture. The results were considered in connection with the systematics of the even krypton isotopes and compared with a two-quasiparticle-plas-rotor model calculation. (HSI)

  3. Removal of polonium contamination by lead-bismuth eutectic in nuclear systems

    International Nuclear Information System (INIS)

    Miura, Terumitsu; Obara, Toru; Sekimoto, Hiroshi

    2003-01-01

    Lead-Bismuth eutectic (LBE) is considered as a promising candidate of the coolant of liquid metal cooled fast reactor, and the coolant and/or target of accelerator driven system. LBE has various good characters for coolant, but it has also some problems such as polonium production. It is necessary to take polonium contamination into consideration, when LBE is used as the coolant. In the present paper, the removal of contaminating polonium from material surface is studied. Baking method is investigated for polonium removal from contaminated quartz glass plate in vacuum. Before and after baking, the mass of the contaminants on the surface and alpha particle counts from contaminated surface is measured. When the contaminated quartz glass plates are baked at more than 400degC for a few minutes, alpha particle counts from the surface decreases by more than 99.7%, and the mass of contaminants decreases by more than 50%. When the baking was performed at 300degC for 15 minutes and more, alpha particle count decreases by more than 80%, and the mass decreases in little. When, the baking temperature is lower than 200degC, alpha particle counts and mass do not decrease. (author)

  4. Lead-210, polonium-210, and stable lead in the food-chain lichen, reindeer and man

    International Nuclear Information System (INIS)

    Persson, B.R.

    1972-01-01

    The measurements of stable lead and the natural fallout radionuclides lead-210 and polonium-210 in communities of lichen (Cladonia alpestris) in central Sweden from 1961 to 1970 indicate a quite constant level. The average lead-210 content per unit area in lichen carpets was found to be 15 +- 2 nCi m -2 , the average lead-210 activity concentration 6.7 +- 0.9 nCi per kg dry weight and the lead-210 specific activity 630 +- 60 nCi per g of stable lead. The polonium-210/lead-210 activity ratio was about 0.9 +- 0.1. The vertical distribution of lead-210 in the lichen carpet showed a maximum concentration in the top layer. The distribution was similar during 1967 and 1968 but the low amount of precipitation during 1968 and 1969 disturbed the distribution pattern in 1969 and 1970. The transfer of lead-210, polonium-210 and stable lead through the food chain: lichen, reindeer, and man was characterized. The absorbed dose rate in Lapps due to polonium-210 was estimated to be about 6 to 8 mrad per year in gonads and 8 to 20 mrad per year in bone tissues. This is about ten percent of their entire absorbed dose contribution from all natural radiation sources. (U.S.)

  5. Polonium 210Po activities in human blood of patients with ischaemic heart disease from Gda?sk in Poland

    OpenAIRE

    Bory?o, Alicja; Skwarzec, Bogdan; Roma?czyk, Grzegorz; Siebert, Janusz

    2013-01-01

    The determination of polonium 210Po in human blood samples is presented and discussed in this paper. The human blood samples were collected from patients of Medical University of Gda?sk with ischaemic heart disease (morbus ischaemicus cordis, MIC). The polonium concentrations in analyzed human blood samples are very differentiated. 210Po is of particular interest in public health and although is present in the environment in extremely low amounts, it is easily bioaccumulated to the human body...

  6. Study on auto-plating process time versus recovery for polonium, Po-210 in environmental sample

    International Nuclear Information System (INIS)

    Jalal Sharib; Zaharudin Ahmad; Abdul Kadir Ishak; Norfaizal Mohamed; Ahmad Sanadi Abu Bakar; Yii Mei Wo; Kamarozaman Ishak; Siti Aminah Yusoff

    2008-08-01

    This study was carried out to evaluate time effectiveness and recovery 16 samples of 4 Kuala Muda stations during auto-plating process procedures for determination Polonium, Po 210 activity concentration in environmental sample. The study was performed using Kuala Muda sediment as sample in the same methodology. The auto-plating process runs for 4, 12, 24 and 30 hours on a silver disc for 4 samples each station, and then counted for one (1) day using an alpha spectrometry counting system. The objectives for this study is to justify on time duration for auto-plating process effecting a chemical yield of Po-209.The results showed recovery are increasing versus time and constantly at 24 hour auto-plating. Its mean, 24 hour is an optimum time for auto-plating process for determination of Polonium, Po 210 activity concentration in environmental sample. (Author)

  7. Radiocesium and polonium in seals from the Baltic Sea. A preliminary study

    International Nuclear Information System (INIS)

    Holm, E.; Leisvik, M.

    2002-01-01

    137 Cs and 210 Po in muscle, liver and kidney from 5 seals from the Baltic Sea have been studied. Assuming that the seals consume 5% of their own body weight each day and by using previously obtained data for the doses in fish, the biological half time has been estimated to 20 days for Cesium and 35 days for Polonium. The maximum yearly doses are calculated to 76 μGy from 137 CS to muscle and 3 500 μGy to kidneys from 210 Po. These data are very preliminary, the number of individuals being so small, and it is difficult to estimate how much food other than fish the seals consume. Furthermore only few data for radioactive concentrations in whole fish exist, which especially impacts the results for Polonium. (LN)

  8. Intake of lead210 and polonium210 by inhalation of atmospheric air and cigarette smoke

    International Nuclear Information System (INIS)

    Brigido Flores, Osvaldo; Montalvan Estrada, Adelmo; Alonso Hernandez, Carlos; Tomas Zerquera, Juan

    2004-01-01

    The electroplating of polonium at two different times onto copper disks and further measurement of alpha activity was the method used for 210Po determination in atmospheric air and tobacco products. The Polonium daughter is used to determine both the 210 Pb and 210 Po using the Bateman equations for radioactive growth and decay. The values of 210 Pb and 210 Po measured in the ground-level air reported average concentrations of 0.65 and 0.06 mBq.m-3, respectively. A cigarette contains an average activity of 13.0 mBq of 210 Pb and 10.4 mBq of 210 Po for different Cuban cigarette brands. The weighted-average annual effective dose estimated due to inhalation of these nuclides was computed to be 38 Sv, corresponding to the 26.8% of the total effective dose received by intake of 210 Pb and 210 Po in area of natural radioactive background

  9. Exposure of cuban population due to dietary intake of lead 210 and polonium 210

    International Nuclear Information System (INIS)

    Brigido Flores, O.; Barreras Caballero, A.; Montalvan Estrada, A.; Alonso Hernandez, C.; Tomas Zerquera, J.

    2000-01-01

    Data are presented on the concentrations of 210Pb and 210Po in potable water and different food items collected from various locations in Cuba. The electroplating of polonium at two different times onto copper disks and further measurement of alpha activity was the method used for 210Po determination in foods and water. The Polonium daughter is used to determine both the 210Pb and 210Po using the Bateman equations for radioactive growth and decay. The average 210Pb and 210Po concentration in potable water was 3 and 2 mBq.l-1, respectively and concentration in total diet averaged 47.7 mBq.kg-1 for 210Pb and 131.9 mBq.kg-1 for 210Po. The annual effective dose estimated due to ingestion of these nuclides contained in foods and potable water reported a value of 77.7 [Sv corresponding the 95.7 % to the food consuming

  10. Accumulation of polonium 210Po in tissues and organs of deer carvidae from Northern Poland.

    Science.gov (United States)

    Skwarzec, Bogdan; Prucnal, Malgorzata

    2007-01-01

    This study was undertaken to provide information on accumulation of polonium in tissues and organs of deer carvidae in order to assess the potential transport of this element via food-chain to game meat consumers. Livers, kidneys and muscles of large herbivorous animals belonging to three species: roe deer (Capreolus capreolus), red deer (Cervus elaphus) and fallow deer (Dama dama), collected in Northern Poland, were the subject of the present investigation. Activities of (210)Po were determined by means of alpha spectrometry along with relevant radiochemical procedures. The concentration of (210)Po in analyzed animals decreased in the order kidney > liver > muscle tissue. The average activity concentrations of (210)Po ranged between 0.02 +/- 0.01 Bq. kg(- 1) w.w. in muscles and 7.15 +/- 0.12 Bq. kg(- 1) w.w. in kidneys. Levels of polonium were not influenced by sampling location, sex, age and species of animals.

  11. Speciation, analysis and ion exchange behavior of polonium and other natural radionuclides in drinking water

    International Nuclear Information System (INIS)

    Katzlberger, C.J.

    2000-09-01

    In the first chapter of this work, the hydrolysis reaction of trace amounts of polonium was studied with a cation exchange method. In a 1 M (H,Na)ClO4 solution with p[H] > 0.3, polonium occurred in the form of univalent cation Po(OH)3+ and a neutral species Po(OH)4. The former is predominant in strongly acidic media (0.3 90 % determined via lead recovery with AAS. Minimum detectable activities of 0.4 mBq/l and 1.0 mBq/l could be achieved for 210Po and 210Bi (210Pb) respectively. Results ranged from 1.5-20 mBq/l and more in cases of extremely high 222Rn concentrations. Post sampling radon decay during the period between sampling and analysis plays an important role and strongly influences the obtained results. (author)

  12. Radiation studies in Lens culinaris: impact of absorbed polonium on microsporogenesis

    International Nuclear Information System (INIS)

    Singh, V.K.; Tauheed, Nusrat; Jha, V.N.; Tripathi, R.M.

    2008-01-01

    The root systems of fully grown plants of Lens culinaris (2n=14) were exposed to solutions of different concentrations of polonium (mixture of 208 Po and 209 Po Energy of alpha being 5.1 MeV and 4.9 MeV respectively). Variability in duration of exposure was also maintained. The controlled samples showed normal behavior of chromosomes forming seven bivalents with varying numbers of chiasmata. However, the pollen grain mother cells (PMC) of treated plants harbored a broad spectrum of chromosomal aberrations viz. Clumped configurations, multivalent formation, sticky anaphase bridge and laggards. Clumped configurations following surface stickiness was the most prominent manifestation. It appeared that the alpha particles emitted by the polonium atoms, logged in different organs including the anthers, created a situation akin to chronic internal radiation and inflicting injuries of different extent on the chromosome surface. (author)

  13. Polonium-210 in mussels and fish from the Baltic-North Sea estuary

    DEFF Research Database (Denmark)

    Dahlgaard, H.

    1996-01-01

    Polonium-210 has been measured in Danish fish meat caught in the North Sea, the Kattegat and the Baltic in 1991-1994. Average values of 0.35, 0.65 and 0.96 Bq Po-210 kg(-1) fresh weight were observed for cod, herring and plaice fillets, respectively. The difference between species is statistically...... in fish and mussels may represent a natural baseline. Copyright (C) 1996 Elsevier Science Ltd....

  14. Phase stability, elasticity, and theoretical strength of polonium from first principles

    Czech Academy of Sciences Publication Activity Database

    Legut, Dominik; Friák, Martin; Šob, Mojmír

    2010-01-01

    Roč. 81, č. 21 (2010), 214118/1/-214118/19/ ISSN 1098-0121 R&D Projects: GA AV ČR IAA100100920; GA MŠk(CZ) OC10008 Institutional research plan: CEZ:AV0Z20410507 Keywords : polonium * phase stability * elasticity * theoretical strength * ab initio calculations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.772, year: 2010

  15. Polonium content in sediments and other solid tailings generated by mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Chmielewska, Izabela; Michalik, Boguslaw [Silesian Centre for Environmental Radioactivity, Central Mining Institute, 40-166 Katowice, Pl. Gwarkow 1 (Poland)

    2014-07-01

    All legal limits or recommendations concerning NORM include only primordial radionuclides and secular equilibrium state among all decay products is assumed. This is not valid for a majority of residues from NORM industry where activity concentration of progenies can substantially differ each other. Upper Silesia Coal Basin is a unique region where mining activity is continuously done over longer period of time and this include discharging of radium-bearing water to environment and creating huge amount of solid wastes where at the beginning radium is the most dominant radionuclide. With time other daughter products start to build up and actual exposure to radiation is changing. One of them is polonium that with regard to its chemical properties can be easily accumulated in non-human biota resulting in the increase of radiation exposure. In our work we focused attention on sediments where content of {sup 210}Po was determined by chemical separation followed by alpha spectrometry. Chemical preparation involves organic matter destruction and dissolution of the sample itself (if possible). In our research we employed wet digestion by means of mixture of concentrated acids: HNO{sub 3}, HClO{sub 4}, HCl. Later on polonium was spontaneously deposited onto silver disc and measured with use of alpha spectrometry. In this article we want to show results of our study and as well to present some conclusions concerning changes in radiation risk assessment when actual concentration of polonium is taken into consideration. (authors)

  16. Neutron-rich polonium isotopes studied with in-source laser spectroscopy

    CERN Document Server

    Dexters, Wim; Cocolios, T E

    This work studies the unknown region of neutron rich polonium isotopes. The polonium isotopes, with Z=84, lie above the magic lead nuclei (Z=82). The motivation for this research can mainly be found in these lead nuclei. When looking at the changes in the mean square charge radii beyond the N=126 shell gap, a kink is observed. This kink is also found in the radon (Z=86) and radium (Z=88) isotopes. The observed effect cannot be reproduced with our current models. The polonium isotopes yield more information on the kink and they are also able to link the known charge radii in lead isotopes to those in radon and radium. Additionally, the nuclear moments of the odd-neutron isotope $^{211}$Po are investigated. This nucleus has two protons and one neutron more than the doubly magic nucleus $^{208}$Pb. Nuclear moments of isotopes close to this doubly magic nucleus are good tests for the theoretic models. Besides pushing the models to their limits, the nuclear moments of $^{211}$Po also yield new information on the f...

  17. Study of neutron deficient iridium isotopes by using laser spectroscopy; Etude des noyaux d'iridium deficients en neutrons par spectroscopie laser

    Energy Technology Data Exchange (ETDEWEB)

    Verney, D

    2000-12-19

    Resonance ionization spectroscopy was performed on neutron deficient iridium isotopes {sup 182-189}Ir, {sup 186}Ir{sup m} and stable isotopes {sup 191,193}Ir. Hyperfine spectra were recorded from the optical transition at 351,7 nm between the 5d{sup 7}6s{sup 2} {sup 4}F{sub 9/2} ground state and the 5d{sup 7}6s6p {sup 6}F{sub 11/2} excited state. Radioactive iridium isotopes were obtained from {beta}{sup +}/EC decay of radioactive mercury nuclei deposited on a graphite substrate. The radioactive mercury nuclei were produced at the ISOLDE facility at CERN through spallation reactions, by bombarding a molten lead target with the 1 GeV proton beam delivered by the PS-Booster. Magnetic dipole moments and spectroscopic quadrupole moments were extracted from the hyperfine spectra. The mean square charge radius variations, as deduced from the measured isotopic shift, show a sharp change between {sup 187}Ir and {sup 186}Ir{sup g}, accompanied by a sudden increase in deformation: from {beta}2 {approx} 0,16 to {beta}2 > 0, 2. These results were analysed in the framework of an axial rotor plus one or two quasiparticles. The wave functions of the osmium and platinum cores which are used in order to describe the iridium nuclei were calculated from the HF+BCS method with the Skyrme SIII effective interaction. The cores were constrained to take the deformation parameters extracted from the isotopic shift measurements. One shows then that this sudden deformation change corresponds also to a change in the proton state that describes the odd nuclei ground state or that participates in the coupling with the neutron in odd-odd nuclei. This state is identified with the {pi}3/2{sup +}[402] orbital for the smaller deformations nuclei and with the {pi}1/2{sup -}[541] orbital stemming from the h{sub 9/2} subshell for bigger deformations nuclei. (author)

  18. Prediction of energies of yrast band in some even-even nuclei

    International Nuclear Information System (INIS)

    Varshney, A.K.; Singh, Yuvraj; Gupta, D.K.; Singh, M.; Gupta, K.K.; Bihari, Chhail; Dhiman, S.K.

    2012-01-01

    The deformation parameter β and γ of the collective model of Bohr and Mottelson are basic descriptors of the nuclear equilibrium shape and structure. The researchers found that the values of γ obtained from energies (= γ e ) are nearly equal to the value of γ derived from transition rate (= γ b ) in even Xe, Ba and Ce nuclei (A∼120-140) and Hf, W, Os, Pt and Hg nuclei (A∼160-200) using rigid triaxial rotor model of Davydov-Filippov. In the present study, the relatively light mass nuclei (Mo, Ru and Pd) have been taken. As far as γ is concerned, it is known that the Ru chains of nuclei is intermediate between the two having opposite trends for parameter γ, decreasing for Mo and increasing for Pd, and has an irregular behaviour in itself with the increase of neutron number

  19. Fragmentation of two-quasiparticle states in 92Zr and even-even Sn isotopes

    International Nuclear Information System (INIS)

    Solov'ev, V.G.; Stoyanova, O.; Voronov, V.V.

    1981-01-01

    The fragmentation of two-quasiparticle states in doubly even spherical nuclei is calculated within the quasiparticle-phonon nuclear model. The fragmentation is due to the interactions leading to the formation of phonons and to the quasiparticle-phonon interaction. The spectroscopic factors for the ''particle-valence particle'' states in 92 Zr are calculated. The agreement with the experimental data of the reaction 91 Zr(d, p) 92 Zr is obtained. The centroid energy Esub(jjsub(0)) and width GITAsub(jjsub(0)) are calculated for the configurations excited in the (p, d) reactions on odd-A isotopes of Cd, Sn and Te. It is shown that the valence particle-hole lgsub(9/2) configuration is localized at the excitation energies of 7-9 MeV. The corresponding experimental data are well described

  20. The decay from the two-quasiparticle regime in even-even deformed rare earth nuclei

    International Nuclear Information System (INIS)

    Henriques, A.; Thorstensen, T.F.; Hammaren, E.

    1983-06-01

    A bump at 1 MeV has been identified in coincidence gamma-ray spectra from the ( 3 He, 4 He) reaction in deformed rare earth nuclei. Particle/gamma-ray angular correlation indicates a dipole character. It is suggested that this bump corresponds to transitions from two-quasiparticle states to the ground state band

  1. Structure of Even-Even 218-230 Ra Isotopes within the Interacting Boson Approximation Model

    Directory of Open Access Journals (Sweden)

    Diab S. M.

    2008-01-01

    Full Text Available A good description of the excited positive and negative parity states of radium nuclei (Z=88, N=130-142 is achieved using the interacting boson approximation model (IBA-1. The potential energy surfaces, energy levels, parity shift, electromagnetic transition rates B(E1, B(E2 and electric monopole strength X(E0/E2 are calculated for each nucleus. The analysis of the eigenvalues of the model Hamiltonian reveals the presence of an interaction between the positive and negative parity bands. Due to this interaction the $Delta I = 1$ staggering effect, between the energies of the ground state band and the negative parity state band, is produced including beat patterns.

  2. Real and complex boson expansions in even-even deformed nuclei

    International Nuclear Information System (INIS)

    Silvestre-Brac, B.; Piepenbring, R.

    1977-01-01

    Analysis of real and complex boson expansions of the Kishimoto-Tamura type is performed in a deformed basis in order to allow a further study of the anharmonicities of vibrations in deformed nuclei. It is shown that complex solutions cannot be found in the cases where no real one exists. (Auth.)

  3. Low energy structure of even-even Ni isotopes close to 78Ni

    International Nuclear Information System (INIS)

    Rykaczewski, Krzysztof Piotr; Mazzocchi, C.; Grzywacz, Robert Kazimierz; Batchelder, J.C.; Bingham, Carrol R.; Fong, D.; Hamilton, J.H.; Hwang, J.K.; Karny, M.; Krolas, W.; Liddick, S.N.; Lisetskiy, A. F.; Morton, N.H.; Mantica, P.F.; Mueller, W.F.; Steiner, M.; Stolz, A.; Winger, J.A.

    2005-01-01

    The structure of magic neutron-rich nickel isotopes produced in the fragmentation of a 140 A MeV 86 Kr beam was investigated. For the first time four gamma transitions were assigned to the decay of the I π =8 + , T 1/2 = 590 +180 -110 isomer, thus establishing the 0 + -2 + -4 + -6 + -8 + ground-state band in 76 Ni. The previously unknown 2 + and 4 + levels belonging to the ground-state band in 74 Ni were identified in the β decay of 74 Co (T 1/2 =30(3) ms). The decay properties of 72 Co → 72 Ni were verified and confirmed on the basis of γ-γ coincidence data. The relevance of the measured level properties for the magicity of 78 Ni is analyzed with the help of advanced shell-model predictions

  4. Band structure of even-even selenium isotopes in the proton-neutron interacting boson model

    International Nuclear Information System (INIS)

    Kaup, U.; Moenkemeyer, C.; Brentano, P. von

    1983-01-01

    Available systematic IBM calculations [1-6] for Krypton and Strontium isotopes have been extended to Selenium. The analysis in terms of the IBM is complicated by the interplay of collective and noncollective degrees of freedom. However, satisfactory agreement has been obtained for N>=42. (orig.)

  5. The influence of the shell closure on the microscopic structure of even-even Hg isotopes

    International Nuclear Information System (INIS)

    Burghardt, A.J.C.

    1989-01-01

    Muonic X-ray data were obtained for 198 200 202 204 Hg at high-intensity muon-beam facility of SIN and an electron-scattering study was performed on 204 Hg with the 500 MeV, high-resolution electron-scattering facility of NIKHEF-K in a q-range from 0.4 to 2.9 fm -1 . The combined analysis of the elastic electron-scattering and muonic X-ray data has yielded the ground-state charge distribution of 204 Hg. Hartree-Fock calculations with four different interactions, with and without the inclusion of pairing correlations, are compared to this experimental result. The charge-density difference between 206 Pb (determined elsewhere) and 204 Hg is then used ot investigate the filling of the last proton orbit before the Z=82 shell closure, the 3s 1/2 orbit. The interpretation of this difference, also in terms of Hartree-Fock calculations, is discussed in conjunction with the earlier study of Frois et al. concerning 206 Pb and 205 Tl. Many excited states have been observed in the spectra of 204 Hg. The experimental excitation energies and the spins and parities assigned to a number of states are presented. From the cross-section data for these states transition charge distributions have been extracted. Shell-model predictions are compared with the observed level scheme and the shell-model calculation performed by Poppelier is used to interpret transition charge distributions of six states. 101 refs.; 32 figs.; 41 figs

  6. Regional regularities for the even-even nuclei in intermediate mass region

    International Nuclear Information System (INIS)

    Varshney, Mani; Singh, M.; Gupta, D.K.; Singh, Yuvraj; Gupta, K.K.; Bihari, Chhail; Sharma, Aparna; Varshney, A.K.

    2011-01-01

    With the development of experimental techniques more and more nuclear data are accumulated and compiled for over five decades. The proton neutron interaction has been considered the key ingredient in the development of collectivity and ultimately the deformation in atomic nuclei. The purpose of the present study is to analyze the growth of R4/2 in different mass regions. The rate of growth regions in regions having proton number Z = 38, 54, 60 and 76 with changing neutron number where the interaction between particle - particle, particle - hole and hole - hole

  7. Triaxial shapes in the ground states of even-even neutron-rich Ru isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Lister, C.J.; Morss, L.R. [and others

    1995-08-01

    Partial level schemes for {sup 108,110,112}Ru, and {sup 114}Ru about which nothing was previously known, were determined from the measurement of prompt, triple-gamma coincidences in {sup 248}Cm fission fragments. A 5-mg {sup 249}Cm source, mixed with 65-mg KCl and pressed in the form of a 7-mm diameter pellet, was used for the experiment. Prompt {gamma} rays emitted from the fission fragments were detected with the Eurogam array at Daresbury, which at that time consisted of 45 Compton suppressed Ge detectors and 5 LEPS spectrometers. Transitions in Ru were identified by gating on {gamma} rays in the complementary Te fragments. Figure I-25 shows the technique used to identify the previously unknown transitions in {sup 114}Ru and its partial level scheme. High spin states up to spin 10 h were observed and the {gamma}-ray branching ratios were determined. The ratios of electric quadrupole transition probabilities deduced from the experimental branching ratios were found to be in good agreement with the predictions of a simple model of rigid triaxial rotor. Our analysis shows that gamma deformation in Ru isotopes is increasing with the neutron number and the gamma value for {sup 112}Ru and {sup 114}Ru is {approximately} 25 degrees. This is one of the highest gamma values encountered in nuclei, suggesting soft triaxial shapes for {sup 112}Ru and {sup 114}Ru. The results of this investigation were published.

  8. Research on the behavior of polonium produced in lead-bismuth eutectic irradiated with neutrons. JAERI's nuclear research promotion program, H10-026. Contract research

    International Nuclear Information System (INIS)

    Sekimoto, Hiroshi; Igashira, Masayuki; Yano, Toyohiko; Obara, Toru; Ohsaki, Toshiro

    2002-03-01

    Lead-Bismuth Eutectic (LBE) is proposed by several research institutes as a coolant of liquid metal cooled fast reactors, instead of sodium, and a target of accelerator driven subcritical nuclear reactor systems (ADS). LBE has some advantages that it is chemically inert compared to sodium and that its melting point is low like sodium. A problem might be that bismuth produces polonium, which is an alpha emitter, by irradiation of neutrons. The purpose of the study is to get information for quantitative estimations of the release of polonium on LBE cooled fast reactors and on ADSs by making it clear about production rate of polonium (information about cross section) by neutron irradiation of LBE, release rate of the produced polonium from LBE, and adsorption rate of the polonium on various materials. To get the information about production rate of polonium, neutron cross sections of bismuth were measured in keV energy region, which was important in fast reactors, by using the Pelletron accelerator in Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology. The obtained neutron capture cross sections were from 1/2 to 1/3 of the evaluated values in JENDL and the obtained polonium production cross sections were almost 1/3 of it. At the same time, an experimental device was designed for heating and adsorption experiments and the performance was tested. The performance of alpha spectrometer was tested also. By those the method was established for the measurement of polonium released from melted LBE after neutron irradiation. (author)

  9. Preparation of a Strong Thin Polonium Source And Preliminary Experiments on the Yield of (α,n) Reactions

    International Nuclear Information System (INIS)

    Broda, E.

    1945-01-01

    This report was written by E. Broda and P. K. Wright at the Cavendish Laboratory (Cambridge) in July 1945 and is about the preparation of a strong thin polonium source and preliminary experiments on the yield of (alpha,n) reactions. This report includes the experiment description, the discussion of the results and consist of 4 parts: (1) the electrode position of polonium under different conditions (2) a standard procedure for preparation of strong thin Po sources (3) a simple method for the recovery of RaD from complex mixtures (4) some preliminary experiments with a Po source. (nowak)

  10. Preparation of a Strong Thin Polonium Source And Preliminary Experiments on the Yield of (α,n) Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Broda, E.

    1945-07-01

    This report was written by E. Broda and P. K. Wright at the Cavendish Laboratory (Cambridge) in July 1945 and is about the preparation of a strong thin polonium source and preliminary experiments on the yield of (alpha,n) reactions. This report includes the experiment description, the discussion of the results and consist of 4 parts: (1) the electrode position of polonium under different conditions (2) a standard procedure for preparation of strong thin Po sources (3) a simple method for the recovery of RaD from complex mixtures (4) some preliminary experiments with a Po source. (nowak)

  11. Determination of polonium 210 in different types of tobacco consumed in Sudan

    International Nuclear Information System (INIS)

    Abdulrahman, M. E.

    2011-01-01

    The carcinogenic effect of 210 Po with respect to lung cancer is an important problem in many countries with very high cigarette consumption. Sudan is one of the consumptions of cigarettes in the world. The aim of this study was the determination polonium-210 in different parts of tobacco plant comes from China and Brazil consumed in cigarette in Sudan and determination of 210 Po in five most frequently smoked brands more consumption in Sudan. The annual committed effective dose from cigarette was determined and comparison with other results reported in literature. The tobacco plant (leaves and root) for analysis were collected from Haggar factory in Sudan and another brand were collected randomly from markets, only the most popular one was chosen for analysis (Bringi, Lord, Winner, Goal, Benson). The polonium-210 activity was measured on an alpha-spectrometer equipped with semiconductor surface barrier silicon detectors after spontaneously plated onto asilver disc from hydrochloric acid medium. Polonium samples were measured for 2-3 days. The accuracy and precision of radiochemical method were evaluated using (IAEA-326). The values of activity concentration of 210 Po found in cigarettes consumed in Sudan are within of the range of values found in the literature. The 210 Po presented concentration in different brands ranging from 22.8 to 51.6 Bqkg -1 (average 36.54 Bq kg -1 ). The activity concentration of 210 Po in popular brand cigarette tobacco is higher than that in fine brand cigarette tobacco. Found the highest concentration in the raw material compared to the final product is attributed that to the import, storage and manufacturing processes. Activity determination indicates those cigarettes consumed in Sudan are comparable to the values reported in China and Brazil that the raw material comes from these two countries. The polonium is non-uniformly distributed within the tobacco plants analyzed in this study, the highest levels were found in the leaves

  12. Polonium release from an ATW burner system with liquid lead-bismuth coolant

    International Nuclear Information System (INIS)

    Li, N.; Yefimov, E.; Pankratov, D.

    1998-04-01

    The authors analyzed polonium release hazards in a conceptual pool-type ATW burner with liquid lead-bismuth eutectic (LBE) coolant. Simplified quantitative models are used based on experiments and real NPP experience. They found little Po contamination outside the burner under normal operating conditions with nominal leakage from the gas system. In sudden gas leak and/or coolant spill accidents, the P contamination level can reach above the regulation limit but short exposure would not lead to severe health consequences. They are evaluating and developing mitigation methods

  13. Determination of polonium 210 in different types of tobacco consumed in Sudan

    Energy Technology Data Exchange (ETDEWEB)

    Abdulrahman, M E [Sudan Academy of Sciences, Atomic Energy Council, Khartoum (Sudan)

    2011-01-15

    The carcinogenic effect of {sup 210} Po with respect to lung cancer is an important problem in many countries with very high cigarette consumption. Sudan is one of the consumptions of cigarettes in the world. The aim of this study was the determination polonium-210 in different parts of tobacco plant comes from China and Brazil consumed in cigarette in Sudan and determination of {sup 210} Po in five most frequently smoked brands more consumption in Sudan. The annual committed effective dose from cigarette was determined and comparison with other results reported in literature. The tobacco plant (leaves and root) for analysis were collected from Haggar factory in Sudan and another brand were collected randomly from markets, only the most popular one was chosen for analysis (Bringi, Lord, Winner, Goal, Benson). The polonium-210 activity was measured on an alpha-spectrometer equipped with semiconductor surface barrier silicon detectors after spontaneously plated onto asilver disc from hydrochloric acid medium. Polonium samples were measured for 2-3 days. The accuracy and precision of radiochemical method were evaluated using (IAEA-326). The values of activity concentration of {sup 210} Po found in cigarettes consumed in Sudan are within of the range of values found in the literature. The {sup 210} Po presented concentration in different brands ranging from 22.8 to 51.6 Bqkg{sup -1}(average 36.54 Bq kg{sup -1}). The activity concentration of {sup 210} Po in popular brand cigarette tobacco is higher than that in fine brand cigarette tobacco. Found the highest concentration in the raw material compared to the final product is attributed that to the import, storage and manufacturing processes. Activity determination indicates those cigarettes consumed in Sudan are comparable to the values reported in China and Brazil that the raw material comes from these two countries. The polonium is non-uniformly distributed within the tobacco plants analyzed in this study, the highest

  14. Plutonium and polonium concentrations in the different water masses crossing the Strait of Gibraltar

    International Nuclear Information System (INIS)

    Gasco, C.; Anton, M.P.

    1999-01-01

    In this paper total Pu and Po concentrations in the water column are presented as part of a study to determine the exchange fluxes and overall budget of these selected nuclides within the Atlantic and Mediterranean basins. Polonium is a natural radionuclide continuously input to the sea via atmospheric deposition from the radon existing in the air. Plutonium is a man-made radionuclide that was mostly introduced in the atmosphere during the 60's nuclear testing. Since then, it has been gradually disappearing due to fallout and the banning of nuclear atmospheric explosions

  15. Particulate uranium, plutonium and polonium in the biogeochemistries of the coastal zone

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, V F; Koide, M; Goldberg, E D [Scripps Institution of Oceanography, La Jolla, CA (USA)

    1979-01-18

    It is stated that although increasing attention has been paid to the role of inorganic solid phases in the chemistry of seawater, little quantitative data has been available to assess their involvement with living systems. Recent observations are here reported on the uptake of uranium, plutonium and polonium in coastal waters by organisms and submerged surfaces as traced by their isotopes. It is shown that the body burdens of these radioelements in some marine organisms are governed measurably by the uptake of their particulate forms. Furthermore, these elements are associated with different particulate phases, as deduced from the rates at which they deposit on submerged surfaces.

  16. Comparative uptake of thorium-230, radium-226, lead-210 and polonium-210 by plants

    Energy Technology Data Exchange (ETDEWEB)

    D' Souza, T J; Mistry, K B

    1970-01-01

    The entry and translocation of /sup 230/thorium, /sup 226/radium, /sup 210/lead, and /sup 210/polonium were examined in nutrient culture experiments. Strontium-89 was included for comparison. Red kidney beans (Phaseolus vulgaris L.) were treated for a period of 15 days. Results indicate that accumulation of /sup 230/thorium, /sup 210/lead and /sup 210/polonium occurs predominantly in roots and only very small amounts of these nuclides are translocated to shoots. Over comparable periods, the accumulation of /sup 226/radium in roots is 2-3 times lower than that of the other nuclides of uranium series. However, the most significant difference between /sup 226/radium and other nuclides is in the extent of their upward transport which for radium is 50-200 times greater. The amount of radium translocated to shoots is comparable to that of strontium. The present evidence of rapid transfer of /sup 226/radium to shoots suggests that among the nuclides examined, /sup 226/radium is likely to make the major contribution to radioactivity in aerial tissues of plants grown under conditions where root absorption is the principal route of entry of the nuclides.

  17. Determination of uranium and polonium in Spa rus aura ta by alpha spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Luna P, M.; Renteria, M.; Montero C, M. E. [Centro de Investigacion en Materiales Avanzados, S. C., Miguel de Cervantes No. 120, Complejo Industrial Chihuahua, 31109 Chihuahua (Mexico); Manjon C, G.; Diaz, I., E-mail: elena.montero@cimav.edu.mx [Universidad de Sevilla, Escuela Tecnica Superior de Arquitectura, Departamento de Fisica Aplicada II, San Fernando No. 4, 41004 Sevilla (Spain)

    2012-06-15

    The aim of this study was optimizing conditions for the specific activities determination of some uranium-series radionuclides present in Spa rus aura ta by alpha spectrometry. Determinations of specific activities were conducted varying the type of digestion: acid attack on hot plate, controlled microwave digestion and acid attack after calcination of the sample. The latter procedure was applied only to the case of uranium isotopes determination. The variation in the isotope extraction method consisted of applying the techniques of liquid-liquid extracting using Tributyl phosphate or chromatographic UTEVA resin. Results depending on the type of treatment given to the samples were compared based on obtained chemical yields. The results reveal a higher bioaccumulation of polonium in the liver sample, with activities of 0.809, 2.495 and 2.439 Bq kg{sup -1} fresh wt compared with the fillet. The best chemical yields of polonium were close to 60% for samples that were digested by microwave. In the case of uranium the best chemical yields, close to 80% for fillet, were obtained with a previous calcination of the sample and using the UTEVA resin. (Author)

  18. Levels of lead-210 (210Pb) and polonium 210 (210Po) in Cuban Tobacco products

    International Nuclear Information System (INIS)

    Brigido, F.O.; Barrerras Caballero, A.; Alvarez Rodriguez, D.; Montalvan Estrada, A.

    1999-01-01

    The release of 210Po in tobacco smoke and the radiation dose for man have been studied because of the high incidence of lung cancer among smoker. The electroplating of polonium at two different times onto copper disks and further measurement of alpha activity was the meted used for 210 Po determination in tobacco products. The Polonium daughter is used to determine both the 210Pb and 210Po using the Baseman equations for radioactive growth and decay. A cigarette contains between 10.6 and 14.7 mBq of 210Pb with an average activity of 13.0 mBq and between 8.5 and 12.3 mBq of 210Po with an average activity of 10.4 mBq for different Cuban cigarette brands. For a person smoking a pack of 20 cigarettes a day, the values of intakes estimated range from 32 to 44 mBq for 210Pb and from 34 to 49 mBq for 210 Po with an average daily intake of 39 mBq for 210 Pb and 42 mBq for 210Po. The annual effective dose estimated due to inhalation of these nuclides contained in cigarette smoke shows a value of 66[Sv and was in correspondence with world-wide range dose, 46 - 90 mSv.year 1 - for tobacco product consumption

  19. Determination of uranium and polonium in Spa rus aura ta by alpha spectrometry

    International Nuclear Information System (INIS)

    Luna P, M.; Renteria, M.; Montero C, M. E.; Manjon C, G.; Diaz, I.

    2012-01-01

    The aim of this study was optimizing conditions for the specific activities determination of some uranium-series radionuclides present in Spa rus aura ta by alpha spectrometry. Determinations of specific activities were conducted varying the type of digestion: acid attack on hot plate, controlled microwave digestion and acid attack after calcination of the sample. The latter procedure was applied only to the case of uranium isotopes determination. The variation in the isotope extraction method consisted of applying the techniques of liquid-liquid extracting using Tributyl phosphate or chromatographic UTEVA resin. Results depending on the type of treatment given to the samples were compared based on obtained chemical yields. The results reveal a higher bioaccumulation of polonium in the liver sample, with activities of 0.809, 2.495 and 2.439 Bq kg -1 fresh wt compared with the fillet. The best chemical yields of polonium were close to 60% for samples that were digested by microwave. In the case of uranium the best chemical yields, close to 80% for fillet, were obtained with a previous calcination of the sample and using the UTEVA resin. (Author)

  20. In-source laser spectroscopy of polonium isotopes: From atomic physics to nuclear structure

    CERN Multimedia

    Rothe, S

    2014-01-01

    The Resonance Ionization Laser Ion Source RILIS [1] at the CERN-ISOLDE on-line radioactive ion beam facility is essential for ion beam production for the majority of experiments, but it is also powerful tool for laser spectroscopy of rare isotopes. A series of experiments on in-source laser spectroscopy of polonium isotopes [2, 3] revealed the nuclear ground state properties of 191;211;216;218Po. However, limitations caused by the isobaric background of surface-ionized francium isotopes hindered the study of several neutron rich polonium isotopes. The development of the Laser Ion Source and Trap (LIST) [4] and finally its integration at ISOLDE has led to a dramatic suppression of surface ions. Meanwhile, the RILIS laser spectroscopy capabilities have advanced tremendously. Widely tunable titanium:sapphire (Ti:Sa) lasers were installed to complement the established dye laser system. Along with a new data acquisition system [5], this more versatile laser setup enabled rst ever laser spectroscopy of the radioact...

  1. Evaluation of sample pretreatment methods for analysis of polonium isotopes in herbal medicines

    International Nuclear Information System (INIS)

    Sreejith, Sathyapriya R.; Nair, Madhu G.; Rao, D.D.

    2014-01-01

    Herbal infusions like ayurvedic aristas are widely consumed by Indian population for good health. With increasing awareness about radiological assessment, an effort was made to assess the radioactivity concentration of naturally occurring radionuclides in herbal medicines. 210 Po is an important alpha particle emitter contributing to internal dose to man from ingestion. Though 210 Po can be spontaneously deposited on silver disk for alpha spectrometric measurements with less radiochemical step, great care has to be taken during the sample pretreatment step owing to the high volatility of polonium even at low temperatures. Aim of the study was to evaluate an appropriate sample pretreatment method for estimation of polonium in herbal medicines. 209 Po was used for radiochemical yield calculation. Conventional open vessel wet ashing, physical evaporation, freeze-drying and microwave digestion in a Teflon vessel were examined. The recovery ranged between 9 and 79%. The lowest recovery was obtained for the samples that were processed by open vessel digestion without any volume reduction. The recoveries were comparable for those samples that were freeze dried and subjected to HNO 3 + HClO 4 + H 2 O 2 + HF acid digestion and microwave digested samples. 210 Po concentration in the samples ranged from 11.3 to 39.6 mBq/L

  2. Determination of uranium and thorium isotopes and polonium in sediment profiles from Baixada Santista, SP

    International Nuclear Information System (INIS)

    Ramos, Guilherme da Franca

    2010-01-01

    The objective of the present work is to determine the activity concentration of uranium and thorium isotopes and polonium in estuarine sediments from Baixada Santista. The area comprehends nine cities in the Brazilian coast (Bertioga, Guaruja, Santos, Sao Vicente, Cubatao, Praia Grande, Mongagua, Itanhaem and Peruibe). It is one of the most important industrial areas in Brazil due to the large number of industries operating in Cubatao, such as steel, petrochemical and fertilizer industries. That, together with a large population, causes a negative impact on the marine biota. In the present work 10 profiles of sediment cores, with depth varying from 41 to 98 cm, were analyzed. The cores were obtained from Santos, Cubatao, Sao Vicente and Bertioga. The cores were sliced every 2 cm and were treated with both physical and chemical processes, including drying, grinding and sieving. The samples were dissolved by acid digestion, till total dissolution and destruction of organic matter. After the acid digestion, the samples were filtered and evaporated till dryness. The radiochemical techniques used to separate the radionuclides and to prepare the final source for alpha counting were ion exchange chromatography and spontaneous deposition for polonium and electrodeposition for U and Th. The final sources were counted in a surface barrier alpha spectrometer. Values obtained for the radionuclides analyzed were similar to the activity concentrations of sediments in non polluted areas, with the exception of a few samples that showed anthropic influence. (author)

  3. Estimation of polonium concentration in groundwater samples from the Peddagattu/Nambapur and Seripalli regions using alpha-spectrometry

    International Nuclear Information System (INIS)

    Raghavendra, T.; Srilatha, K.; Mahender, C.; Elender; Vijaya Lakshmi, T.; Himabindu, V.; Vishwa Prasad; Padma Savithri, P.; Datta, D.; Arunachalam, J.

    2013-01-01

    The decay of uranium series in the earth crust remains the final and long lived radionuclides 210 Po and 210 Pb in the environment. Their presence in the atmosphere is due to the decay of 222 Rn diffusing from the ground. This study was carried out with an objective of estimation of polonium concentration in a uranium mineralized zone in Peddagattu and Seripalli areas of Nalgonda district, Andhra Pradesh, India. Groundwater samples were collected from 12 wells, and frequency of these collections was once in a quarter from May 2010 to Dec 2011. The alpha-spectrometry has been applied to analyze these samples. Observation reveals that the activity concentration of Polonium in the water samples of Peddagattu and Seripally regions range from 0.3 mBq/l to 2.80 mBq/l with Geometric mean of 0.89 mBq/l and Geometric Standard deviation of 2.72 and from 0.3 mBq/l to 4.68 mBq/l with a Geometric mean of 0.91 and Geometric standard deviation of 3.22 respectively. As per WHO standards, the maximum permissible limit in drinking water for Polonium is 0.55 Bq/l. Hence all the 12 samples are falling well under the permissible limit. This paper presents the analytical details for estimating polonium as a natural radioactive element in groundwater as well as surface water samples collected from the Nambapur/Peddagattu and Seripalli regions. (author)

  4. Alpha decay of neutron-deficient isotopes with 52

    CERN Document Server

    Schardt, D; Kirchner, R; Klepper, O; Kurcewicz, W; Roeckl, E; Tidemand-Petersson, P

    1981-01-01

    Using /sup 58/Ni(/sup 58/Ni, xpyn) reactions and on-line mass separation, the alpha -decays of very neutron-deficient isotopes of tellurium, iodine, xenon and cesium were studied. The new isotopes /sup 106/Te (T/sub 1/2/=60/sub -10//sup +30/ mu s) and /sup 110/Xe were identified by their alpha -lines of 4160+or-30 keV and 3737+or-30 keV energy, respectively, with the genetic relationship between the two successive alpha -decays being verified experimentally, while for several other alpha -decaying isotopes more precise data were obtained. The observed alpha -decay properties are discussed within the systematics of energy and reduced width. (19 refs).

  5. Hair as an indicator of the body content of polonium in humans: preliminary results from study of five male volunteers

    International Nuclear Information System (INIS)

    Rääf, C.L.; Holstein, H.; Holm, E.; Roos, P.

    2015-01-01

    The radionuclide 210 Po is of importance from a radiation protection view and has properties that cause special problems when attempting to determine the body content in humans. Estimates have traditionally been made from either urine and/or fecal samples, which require a time-consuming radiochemical preparation before alpha spectrometric determination. In order to find a more simple and less labor intensive method hair has been used as a bioindicator and investigated in this study. The relationship between intake and excretion in hair has been estimated in five volunteers who ingested radioactive polonium ( 209 Po as a bio-tracer for 210 Po) in well determined quantities. Four of the volunteers were given 5–10 Bq 209 Po in a single intake (acute intake) and one volunteer has ingested a daily intake of 58.7 mBq 209 Po for a period of 180 d. Human hair was found to reflect the daily clearance of ingested polonium peaking at 0.001–0.01% d −1 of the ingested amount, thereafter decreasing mono-exponentially, corresponding to a biological half-time of 10–20 days. For the case of protracted intake a mono-exponential build-up was observed with a half-time of 40 ± 5 d. In addition, after cessation of intake, a short-term component (74%) with a biological half-time of 16 ± 4 d, and a long-term component (26%) with a half-time of 93 ± 53 d were observed. It is concluded that hair can be used to detect not only the amount of ingested polonium but also whether the intake was protracted or acute. - Highlights: • After single intakes polonium is excreted in hair with biological half-times (range 15–30 days). • Polonium concentration vs position in hair strand reflects the intake history of subject. • For acute intakes peak hair concentration or daily excretion can be related to the amount of intake. • Protracted intakes of polonium result in an increase in Po concentration in hair, reaching equilibrium after 180 days. • Bi-exponential decay of

  6. Celebration of the radium and polonium discovery as a promotion of nuclear energy in Poland

    International Nuclear Information System (INIS)

    Latek, Stanislaw

    1998-01-01

    The radium and polonium discovery centennial was inaugurated in April 1997. The first event was a Polish-French show of scientific documentary movies on the uses of ionizing radiation and nuclear power. A symposium Radiation - History and Modern Times was organized in spring 1997. Many other interesting events were held throughout 1997. Warsaw hosted an interesting exhibition 'From the Radium Needle to the Medical Accelerators'. A seminar and an exhibition on Radiation Technique in Environmental Protection were organized in cooperation with the IAEA. The Council for Atomic Energy initiated and conducted a workshop on Radioactivity - Risk and Hope. The Polish Academy of Science and the Society of Nuclear Medicine organised a symposium on Polonium and Radium Discovery Impact on Medicine, Radiation Protection and Medical Industry. The National Atomic Energy was the initiator of film shows held for school youth, which turned out to be a great success. The youngsters, mainly from schools bearing the name of Marie Curie, had an opportunity to see films about the great scientist and her discoveries, and on the very phenomenon of radiation. They also had a chance to visit Maria research reactor in the Institute of Atomic Energy in Swierk. Now, at the beginning of February 1998, a three-day scientific session is being held in Warsaw, to commemorate the radium and polonium discovery. Many other events will take place in the coming months. In particular, June 1998, an international conference on Nuclear Physics Close to the Barriers will be held. Another conference, closing the centennial sponsored by UNESCO will focus on the Scientific and Philosophical Consequences of Discovery of Plutonium and Radium, Benefits and Threats to Mankind. Public opinion polls, similar to those conducted in 1996, are planned for spring 1998. The 1996 polls, conducted 10 years after the Chernobyl accident, showed that the majority of Poles feared ionizing radiation and opposed the nuclear power

  7. Evaluation of the contribution of smoking to total blood polonium-210 in Saudi population

    Energy Technology Data Exchange (ETDEWEB)

    Shabana, E.I. E-mail: eshabana@kacst.edu.sa; Elaziz, M.A. Abd; Al-Arifi, M.N.; Al-Dhawailie, A.A.; Al-Bokari, M.M-A

    2000-01-01

    A preliminary study of {sup 210}Po concentrations in the blood of some smokers and nonsmokers is presented in order to evaluate the contribution of smoking to total blood {sup 210}Po in Saudi population. Blood samples were collected from 30 volunteers and analyzed by high resolution {alpha}-spectrometry using a radiochemical technique. The technique is based on the separation of polonium from other components of the sample by wet ashing with an HNO{sub 3}/H{sub 2}O{sub 2} oxidizing mixture and spontaneous deposition on a silver disc under the relevant conditions for {alpha}-particle counting. The results indicated that a significant fraction (about 30%) of blood {sup 210}Po is related to smoking.

  8. The particulate material formed during the combusion of polonium and plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, K.

    1963-11-15

    Over the last decade the production and use of uranium, plutonium and other radioactive materials has developed steadily. The work described in this paper is part of a reasonably comprehensive study of the extent and seriousness of the radiological hazards which could occur as the result of selected types of accidents. Additionally, these studies demonstrate the types of material and operations which are the more likely to produce a serious situation should a mishap occur. The emphasis in the paper, therefore, is on the differences between an element, polonium, of high specific activity which is volatile, and a reactive material, plutonium, of lower specific activity which is non-volatile but of somewhat greater radiotoxicity. The modes of formation of oxide aerosols from these two elements are, to a very considerable degree, representative of two important and contrasting processes.

  9. Bioaccumulation of polonium-210 in fish of the Kaveri river system

    International Nuclear Information System (INIS)

    Shaheed, K.; Shahul Hameed, P.; Iyengar, M.A.R.

    1997-01-01

    Concentration of naturally occurring radioactive nuclide polonium-210 was determined in selected species of fish from the Kaveri river system at Tiruchirappalli. It is shown that 210 Po is non-uniformly distributed within these fishes. Concentrations of 210 Po in the muscle of fish ranged from 3.3 to 8.2 Bq/kg (wet weight). Concentration factors of Po 210 in edible portion of fish from river water worked out to be 2.5 x 10 3 to 6.3 x 10 3 . Radiation dose to public due to consumption of fish from the Kaveri river varied from 5.1 to 27.3 μSv/y. The results have implications that fish represents an important source of supply of 210 Po to humans. (author). 16 refs., 2 tabs

  10. Levels of polonium-210 in the grapevine leaves in Alasehir district in Turkey

    International Nuclear Information System (INIS)

    Gurboga, G.; Aytas Oelmez, S.

    2001-01-01

    The objective of present work is the estimation of Po-210 (polonium) content in the edible grapevine leaves (Vitis viniferae, L.cv Sultana syn.) collected from Gediz plain in Western Turkey. Alasehir District in Gediz plain is one of the most important wine culture region of Turkey. Grapevine leaves are important food material for Dolma in Turkish cuisine. Dolma is a name applied to such vegetables as grapevine leaves, cabbage leaves and green peppers stuffed ground meat or spiked rice. Levels of Po-210 in the grapevine leaves had not been analyzed before in Turkey. In this study, after wet ashing of grapevine leaves, Po-210 was spontaneously plated onto a copper disc from dilute hydrochloric acid medium and deposited activity was measured. The results for Po-210 in the grapevine leaves are compared with the other foodstuff values in the literature

  11. A faster sample preparation method for determination of polonium-210 in fish

    International Nuclear Information System (INIS)

    Sadi, B.B.; Jing Chen; Kochermin, Vera; Godwin Tung; Sorina Chiorean

    2016-01-01

    In order to facilitate Health Canada’s study on background radiation levels in country foods, an in-house radio-analytical method has been developed for determination of polonium-210 ( 210 Po) in fish samples. The method was validated by measurement of 210 Po in a certified reference material. It was also evaluated by comparing 210 Po concentrations in a number of fish samples by another method. The in-house method offers faster sample dissolution using an automated digestion system compared to currently used wet-ashing on a hot plate. It also utilizes pre-packed Sr-resin® cartridges for rapid and reproducible separation of 210 Po versus time-consuming manually packed Sr-resin® columns. (author)

  12. Determination of the electron affinity of astatine and polonium by laser photodetachment

    CERN Multimedia

    We propose to conduct the first electron affinity (EA) measurements of the two elements astatine (At) and polonium (Po). Collinear photo-detachment spectroscopy will allow us to measure these quantities with an uncertainty limited only by the spectral line width of the laser. We plan to use negative ion beams of the two radioactive elements At and Po, which are only accessible on-line and at ISOLDE. The feasibility of our proposed method and the functionality of the experimental setup have been demonstrated at ISOLDE in off-line tests by the clear observation of the photo-detachment threshold for stable iodine. This proposal is based on our Letter of Intent I-148.

  13. Induction of the lambda bacteriophage synthesis in Escherichia coli K 12 by polonium alpha rays

    International Nuclear Information System (INIS)

    Devoret, Raymond

    1958-06-01

    This research thesis reports the study of the inducing action of polonium alpha radiations in Escherichia Coli K 12 by using an external irradiation device. This work comprised the development of a method to spread bacteria in layer with a thickness less than 20 microns, and the measurement of the number of α particles falling on the irradiated surface. This measurement has been performed by using a nuclear emulsion and a simple photographic film. It appears that alpha radiations have an inducing action, and that at most 15 per cent of bacteria can be induced. The comparison of the induction curve with the survival curves of lysogen and sensitive stains shows that there is no abortive induction. Thus, it appears that this inducing action is not due to an indirect effect of the irradiated medium [fr

  14. The Hamburg polonium-210 case. Monitoring of internal contaminations in a malevolent act

    International Nuclear Information System (INIS)

    Dalheimer, A.; Koenig, K.; Nosske, D.; Schaefer, I.

    2009-01-01

    The dead of Alexander Litvinenko in London in the late 2006 was linked with the visit of Dimitri Kovtun. So an investigation was started by the Hamburg Police. As the presence of polonium-210 was uncertain, the action was supported by the Federal Defense against Nuclear Hazards (NGA) of the Federal Office for Radiation Protection (BfS). Radiation measurements in some flats in Hamburg confirmed the suspicion of polonium-210 contaminations. As incorporations by ingestion or inhalation could not generally be excluded, the Coordinating Office on Incorporation Monitoring of the BfS (Leitstelle Inkorporationsueberwachung des BfS) was requested to clarify this issue. The BfS office then coordinated the required bioassay analyses of urine samples carried out at four officially appointed in-vitro laboratories for incorporation monitoring. The group of people to be examined included the members of the family involved living in the contaminated flats, the emergency forces, as well as potentially exposed members of the public. The calculation of the internal dose was based on standard assumptions and also conducted by the BfS. The internal radiation doses proved to be within the range of radiation doses due to natural exposures. Retrospectively it should be stressed that the collaboration and cooperation of all institutions involved in the operation in Hamburg was extremely good despite their differing organisational structures. As a result of the incident in Hamburg various middle and long-term measures have been taken since then by the BfS Coordinating Office on Incorporation Monitoring. (orig.)

  15. Polonium-210 concentration of cigarettes traded in Cuba and their estimated dose contribution due to smoking

    International Nuclear Information System (INIS)

    Brigido Flores, O.; Montalvan Estrada, A.; Fabelo Bonet, O.; Barreras Caballero, A.

    2015-01-01

    Cigarette smoking is one of the pathways that might contribute significantly to the increase in the radiation dose reaching man, due to the relatively large concentrations of polonium-210 found in tobacco leaves. The results of 200 Po determination on the 11 most frequently smoked brands of cigarettes and cigars which constitute over 75% of the total cigarette consumption in Cuba are presented and discussed. Moreover, the polonium content in cigarette smoke was estimated on the basis of its activity in cigarettes, ash, fresh filters and post-smoking filters. 210 Po was determined by gas flow proportional detector after spontaneous deposition of 210 Po on a high copper-content disk. The annual committed equivalent dose for lungs and the annual effective dose for smokers between 12-17 years old and for adults were calculated on the basis of the 210 Po inhalation through cigarette smoke. The results showed concentration ranging from 9.3 to 14.4 mBq per cigarette with a mean value of 11.8 ± 0.6 mBq.Cig -1 . the results of this work indicate that Cuban smokers who smoke one pack (20 cigarettes) per day inhale from 62 to 98 mBq.d -1 of 210 Po and smokers between 12-17 years old who consume 10 cigarettes daily inhale from 30-50 mBq.d -1 . The average committed equivalent dose for lungs is estimated to be 466 ± 36 and 780 ± 60 μSv.year -1 for young and adult smokers, respectively and annual committed effective dose is calculated to be 60 ± 5 and 100 ± 8 μSv for these two groups of smokers, respectively. (Author)

  16. Polonium 210Po activities in human blood of patients with ischaemic heart disease from Gdansk in Poland

    International Nuclear Information System (INIS)

    Alicja Borylo; Bogdan Skwarzec; Grzegorz Romanczyk; Janusz Siebert

    2013-01-01

    The determination of polonium 210 Po in human blood samples is presented and discussed in this paper. The human blood samples were collected from patients of Medical University of Gdansk with ischaemic heart disease (morbus ischaemicus cordis, MIC). The polonium concentrations in analyzed human blood samples are very differentiated. 210 Po is of particular interest in public health and although is present in the environment in extremely low amounts, it is easily bioaccumulated to the human body. The study shows that the amount of 210 Po that is incorporated into the human body depends on the food habits and some difference in its levels could be observed between smokers and non-smokers. (author)

  17. Polonium 210Po activities in human blood of patients with ischaemic heart disease from Gdańsk in Poland.

    Science.gov (United States)

    Boryło, Alicja; Skwarzec, Bogdan; Romańczyk, Grzegorz; Siebert, Janusz

    The determination of polonium 210 Po in human blood samples is presented and discussed in this paper. The human blood samples were collected from patients of Medical University of Gdańsk with ischaemic heart disease ( morbus ischaemicus cordis , MIC ). The polonium concentrations in analyzed human blood samples are very differentiated. 210 Po is of particular interest in public health and although is present in the environment in extremely low amounts, it is easily bioaccumulated to the human body. The study shows that the amount of 210 Po that is incorporated into the human body depends on the food habits and some difference in its levels could be observed between smokers and non-smokers.

  18. Hair as an indicator of the body content of polonium in humans: Preliminary results from study of five male volunteers

    DEFF Research Database (Denmark)

    Rääf, C.L.; Holstein, H.; Holm, E.

    2015-01-01

    radioactive polonium (209Po as a bio-tracer for 210Po) in well determined quantities. Four of the volunteers were given 5-10Bq 209Po in a single intake (acute intake) and one volunteer has ingested a daily intake of 58.7mBq 209Po for a period of 180 d. Human hair was found to reflect the daily clearance...

  19. Method for evaluation of doses from ingestion of polonium, bismuth and lead as natural radioactive material(NORM)

    International Nuclear Information System (INIS)

    Pena, Vanessa; Puerta, Anselmo; Morales, Javier

    2013-01-01

    In this work was carried out an evaluation of dose from ingestion of radioactive daughters of radon (lead, bismuth and polonium), taking into account ages from three months up to adult men, using the new model of the human alimentary tract HATM and methodology of calculating doses proposed by the ICRP publication 103, which allows the estimation of dose based on the concentration of the radionuclide present in the diet or in the water of consumption

  20. Measurement the concentration of polonium 210Po and find annual dose resulting from eating certain foods by the individual Iraqi

    International Nuclear Information System (INIS)

    Al-Emam, A. M.; Mhemeed, A.K.; Hasan, H.I.

    2012-12-01

    The present study aims to determine the concentration of polonium 2 10P o in some of the food consumed by the Iraqi individual collecting (27) sample produced within the country, including imported and available in local markets to some Iraqi provinces, and these foods included potatoes, wheat and fish. To find concentration of polonium 2 10P o method is used chemical separation and deposition on silver disc, and use surface barrier detector to find alpha particle spectrum for polonium and find concentrations ere at 7.15, 2.58, 6.86 Bq / kg, for each of potatoes, wheat and fish, respectively, Daily intake rate for polotuinm 2 10P o which found in the food under study was measured, and show that the annual dose resulting from eating foods that contain this element was at 4.55, 87,69, 0.298 μSv/ y for food stuff mentioned are compatible with universal values and within the permissible limits worldwide. (Author)

  1. Photofission of Even-Even Nuclei Near the Threshold; Photofission des Noyaux Pair-Pair au Voisinage du Seuil; 0424 041e 0422 041e 0414 0415 041b 0415 041d 0418 0415 0427 0415 0422 041d 041e - 0427 0415 0422 041d 042b 0425 042f 0414 0415 0420 0412 0411 041b 0418 0417 0418 041f 041e 0420 041e 0413 0410 ; Fotofision de los Nucleos Par-Par Cerca del Umbral

    Energy Technology Data Exchange (ETDEWEB)

    Rabotnov, N. S.; Smirenkin, G. N.; Soldatov, A. C.; Usachev, L. N. [Fiziko-Energeticheskij Institut, Obninsk, SSSR (Russian Federation); Kapica, S. P.; Cipenjuk, I. Ju.M. [Institut Fizicheskih Problem, Moskva, SSSR (Russian Federation)

    1965-07-15

    exceed 3 to 3.5%. Of the even-even fissionable nuclei investigated, Pu{sup 240} shows the effect of ''quadrupole'' fission most clearly and Th{sup 232} least. The results of the measurements may be used to assess the relationship of the partial cross-sections of photoabsorption in heavy nuclei. The question of the parity of the ground state of Pu{sup 239} is discussed in the context of the results of measurements of the angular distributions of Pu{sup 239} photofission fragments exhibiting a change in the anisotropy sign in accordance with the predictions of the theory for channels with K = 1/2 and 3/2. (author) [French] Les auteurs indiquent les resultats qu'ils ont obtenus en mesurant la distribution angulaire des fragments formes dans la photofission de {sup 238}U, {sup 232}Th, {sup 240}Pu et {sup 239}Pu; les mesures ont ete faites a l'aide d'un faisceau gamma de rayonnement de freinage. Comme source de rayons gamma ils ont utilise le microtron de 12 MeV de l'Institut de physique de l'Academie des sciences de l'URSS. Grace a l'intensite du rayonnement emis, il a ete possible de mesurer les distributions angulaires dans la region des energies gamma a E{sub max} < 6 MeV, qui revet un interet particulier et n'a pas encore ete etudiee. Les recherches ont porte sur les gammes d'energies ci-apres: 5,2 a 9,2 MeV pour {sup 238}U; 5,4 a 6,9 MeV pour {sup 2}'3{sup 2}Th; 5,4 a 7,9 MeV pour {sup 240}Pu; 5,4 a 7,9 MeV pour {sup 239}Pu, Le memoire indique les resultats de la mesure des distributions angulaires dans la photofission de {sup 238}U et {sup 232}Th par rayons gamma provenant de la reaction {sup 19}F(p, {alpha}{gamma}){sup 16}O. Comme source de rayons gamma on a employe une cible epaisse en CaF{sub 2} exposee a des protons de 1,45 MeV. Ces mesures ont permis d'etablir, conformement a la plupart des experiences anterieures, mais contrairement aux donnees obtenues par Lazareva et al. ainsi que par Forknian et Johansson, que dans le domaine d'energie E Less

  2. Evaluation of sample pretreatment methods for analysis of Polonium isotopes in herbal medicine

    International Nuclear Information System (INIS)

    Sathyapriya, R.S.; Nair, Madhu G.; Rao, D.D.

    2013-01-01

    Ayurvedic medicines are widely consumed by Indian population both for treatment and good health Ayurvedic medicines are used in various forms like infusions, decoctions, powder, tablets, fermented decoction (Arishta) etc. Arishtas are prepared using plant extracts soaked in sugar or jaggery and are generally consume on regular basis for good health. Hence an effort was made to analyse the natural radioactivity in the Ayurvedic Arishtas. 213 Po is an important naturally occurring radionuclide that volatilizes beyond 150℃. Hence adequate care is needed during sample pretreatment step. Both physical (freeze-drying, open vessel evaporation and microwave digestion) and chemical (digestion using various mineral acids like aqua regia, Con. HNO 3 , H 2 SO 4 and oxidizing agents like H 2 O 2 and HClO 4 ) pretreatment procedures were adopted. After the initial sample treatment polonium radionuclide was pre-concentrated using calcium phosphate co-precipitation. Calcium phosphate precipitate was dissolved in 150 ml of 0.5M HCI solution with approximately 1 g of ascorbic acid for auto deposition of Polonium on silver planchette for 3 hours at 90℃ on a rotary hot plate. The sample sources were counted in calibrated alpha spectrometer with 450 mm 2 low-back-ground PIPS detector interfaced with ECIL MCA. The spectrum analysis was done using PHAST Software. 209 Po tracer, at low levels was added to the samples for assessing the radiochemical recovery. The recovery ranged between 18-83 %. The lowest recovery was obtained for the samples that were processed by open vessel digestion with HNO 3 + HCIO 4 + H 2 O 2 . The highest recover was for those samples that were freeze dried and subjected to HNO 3 + HCIO 4 + H 2 O 2 acid digestion at 90℃ for 8 hours. 210 Po concentration in a few samples varied between 0.3-3.5 mBq/L. The paper presents the results of radiochemical recoveries for different pretreatment methods and also the 210 Po content in the ayurvedic arishtas. (author)

  3. A study of Polonium in human hair and in fur from animals

    International Nuclear Information System (INIS)

    Holstein, H; Ranebo, Y.; Henriksson, F.; Rääf, C.L.; Holm, E.; Roos, P.

    2013-01-01

    Human hair and hair from animals might serve as good indicators for internal contamination, allowing for the quantification of general environmental levels of certain radioactive elements. From a sampling, analytical and hygienic point of view it would be advantageous to study hair instead of urine and faeces samples. There have been several investigations concerning Polonium in hair. The purpose of this study was to investigate if hair from humans and fur from animals constitute as matrixes for the estimation of the body burden of 210 Po. Human hair taken from 26 individuals from Sweden was analyzed for its 210 Po content. The resulting activity concentration of 210 Po ranged from 0.5 to 4.8 Bq/kg for individuals between the ages of 3 to 32 years and range from 0.5 to 11.5 Bq/kg for individuals between the ages of 32 to 60. This is in agreement with results presented in other studies. The 210 Po in hair might be due to external contamination or in vivo build up from 210 Pb. To help quantify these sources of contamination a couple of human volunteers ingested known amounts of 209 Po (which does not exist in nature). Results from the study showed that 209 Po was rather rapidly detected in the hair samples Human hair consists of 45% Carbon, 7% Hydrogen, 28% Oxygen, 15% Nitrogen and 5% Sulphur. The central core consists of polypeptide chains with hydrogen and disulphide bindings. It is suggested that the sulphide binding is the reason for transfer of Polonium into the hair. Samples from horses; mane, fur, and tail showed activity concentration levels ranging from 6 to 17 Bq/kg, with no significant differences between the various sample types. Fur samples taken from Muskox from Greenland showed much higher concentrations, i.e. 260 Bq/kg. This was expected since the animal graze over vast surface and consumes large amounts of lichen. Deposited radionuclides accumulate in lichens. Fur samples taken from other animals i.e. moose, hare, wild boar, roe deer, and sheep (lamb

  4. Histologic observations on the pathogenesis of lung cancer in hamsters following administration of polonium-210

    International Nuclear Information System (INIS)

    Lisco, H.; Kennedy, A.R.; Little, J.B.

    1974-01-01

    A serial sacrifice experiment was carried out to study the site of origin and the stages in development of lung cancer in hamsters induced by polonium-210 ( 210 Po). 1 or 2 animals were sacrificed weekly during and after a course of 7 intratracheal instillations of 0.1 μCi of 210 Po in saline. This exposure produced a transient radiation pneumonitis of moderate severity during, and for several weeks after, the instillation period. Subsequent pathological changes included hyperplasia of bronchiolar epithelium, and focal proliferation of epithelial cells in peribronchiolar and more remote alveoli, termed epithelialization of alveoli. Hyperplastic bronchiolar epithelium frequently showed numerous Clara cells which exhibited pleomorphism of cells and nuclei, multinucleated cells, and striking changes in staining characteristics of secretory granules. Epithelialization of alveoli showed steady progression from well-circumscribed small foci to larger confluent lesions which were composed of various cell types and resembled tumors. Malignant tumors occurred in many animals surviving more than 24 weeks after the last instillation of 210 Po

  5. Equilibrium evaporation behavior of polonium and its homologue tellurium in liquid lead-bismuth eutectic

    International Nuclear Information System (INIS)

    Ohno, Shuji; Miyahara, Shinya; Kurata, Yuji; Katsura, Ryoei; Yoshida, Shigeru

    2006-01-01

    Experimental study using the transpiration method investigates equilibrium evaporation behavior of radionuclide polonium ( 210 Po) generated and accumulated in liquid lead-bismuth eutectic (LBE) cooled nuclear systems. The experiment consists of two series of tests: preliminary evaporation tests for homologue element tellurium (Te) in LBE, and evaporation tests for 210 Po-accumulated LBE in which test specimens are prepared by neutron irradiation. The evaporation tests of Te in LBE provide the suggestion that Te exists in a chemical form of PbTe as well as the information for confirming the validity of technique and conditions of Po test. From the evaporation tests of 210 Po in LBE, we obtain fundamental data and empirical equations such as 210 Po vapor concentration in the gas phase, 210 Po partial vapor pressure, thermodynamic activity coefficients, and gas-liquid equilibrium partition coefficient of 210 Po in LBE in the temperature range from 450 to 750degC. Additionally, radioactivity concentration of 210 Po and 210m Bi vapor in a cover gas region of a typical LBE-cooled nuclear system is specifically estimated based on the obtained experimental results, and the importance of 210 Po evaporation behavior is quantitatively demonstrated. (author)

  6. Activity levels of polonium-210 in tobacco and cigarette in Iran

    International Nuclear Information System (INIS)

    Ghanbar Moghaddam, B.; Vahabi Moghaddam, M.; Fathi Vand, A. A.

    2011-01-01

    Polonium-210 ( 210 Po) is a natural contaminant of tobacco and its products. Due to its volatility and inherent adsorption properties, 210 Po is one of the major potential sources of human exposure through smoking. This paper reports measurements on 210 Po and 210 Pb levels in domestic as well as imported tobacco to Iran through α-spectrometry technique. The fate of 210 Po radionuclide has been also followed from tobacco farm through curing procedure in factory. The activity levels of 210 Po in Iranian domestic and imported cigarettes is found to be on the average as 38.4±0.8 mBq/g with a range of 30.3-51.3 mBq/g and 20.0±0.6 mBq/g with a range of 18.6-21.7 mBq/g, respectively. These levels are considerably higher than those reported in many other parts of the world. In the case of tobacco produced in Iranian northern province of Guilan, drying in closed compartments by fossil fuel and elevated inventories of 210 Po in soil due to over application of phosphate-rich fertilizers seems to be the main causes of these elevated activity levels.

  7. Radioactive contamination in human by polonium-210 in food from marine origin

    International Nuclear Information System (INIS)

    Kelecom, Alphonse; Gouvea, Rita de Cassia S.; Kelecom, Philippe Marcel

    2005-01-01

    Food from marine origin is considered as one of the sources that most contributes to internal radioactive contamination in humans by polonium-210 ( 210 Po). This work intended to check whether a single ingestion of the mussel Perna perna should result in a detectable increase of radioactive contamination in the consumer. The mussel was bought at a fish market localized in the city of Niteroi, RJ, Brazil. It was cooked as usually, and its content in 210 Po determined after acid mineralization, spontaneous electrodeposition on stainless steel disks and alpha counting. Non-smoking volunteers maintained for two weeks a normal diet, but completely avoiding fish and seafood. Then, they ate 200 g of cooked mussel, and collected total faeces and urine every day during ten days. 210 Po level in faeces samples showed a 900% increase at the first day after ingestion, and reached normal levels after 3-4 days. In urine samples, the increase of 210 Po was much lower (50%) and reached a maximum at the fifth day. Such data showed a short time permanence of 210 Po in the intestine. Most of ingested 210 Po (∼91%) was eliminated in up to 5 days through faeces. A small amount was absorbed (∼5-10%), part of it being eliminated in urine, and the remaining contaminated the human body. (author)

  8. Determination of internal radiation dose due to intake of polonium 210 and lead 210 via smoking

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Kharita, M.H.; Nashawati, A.; Amin, Y.; Al-Akel, B.

    2004-12-01

    In this study, 18 kind of cigarettes and five kinds of molasses consumed by Syrians were collected and analyzed for radioactivity in order to estimate the internal radiation dose caused by 210 Po and 210 Pb intake. Polonium 210 and lead 210 concentrations varied between 4 and 16.4 m Bq/cigarette, while 210 Po distribution ratios in different parts of consumed cigarette were %12, %73, %1.6 in ash, smoke and filter, respectively. In addition, annual intake of 210 Po by a main smoker was varied between 4.4 and 18 Bq/year assuming that the main smoker breathes about 15% of the total 210 Po present in tobacco. Using the values of the annual intake, annual equivalent radiation dose caused by smoking has reached 178 μSv/year. Moreover, mean concentration of 210 Po in nonsmokers and smokers bloods has reached 130 and 97 mBq/l, respectively, while the mean value of 210 Po concentration was relatively higher and reached 176 and 155 mBq/l in smokers and non smoker bloods, respectively (Authors)

  9. Transfer of the uranium decay products, polonium-210 and lead-210, through the lichen-caribou-wolf food chain in northern Canada (manuscript report)

    International Nuclear Information System (INIS)

    Thomas, P.A.

    1991-05-01

    The main purpose of this study is to investigate the accumulation and transfer of polonium-210 and lead-210 in the arctic food chain, lichen-caribou-wolf, in the Northwest Territories. Polonium-210 arises from lead-210 decay and is a widespread alpha-emitting radionuclide. It seeks soft tissue and has the potential to accumulate in the food chain. Caribou, wolves and other wildlife may become exposed to enhanced levels of these two uranium-series radionuclides if the proposed uranium mine near Baker Lake, Northwest Territories, proceeds. Baker Lake lies at the crossroads of the ranges of the Beverly, the Kaminuriak and the Wager Bay caribou herds. Therefore, it is important to establish baseline concentrations and natural food chain transfer of uranium series radionuclides, in this study. This information can be used for baseline data before any further mining development takes place. This study will also provide data regarding the statistical uncertainty attached to transfer coefficients. This can help ensure reliable and appropriate future monitoring of environmental change. With the participation of the hunters of Baker Lake, caribou and wolf samples were collected and analyzed for polonium. Results indicate that polonium-210 activity in caribou tissues were somewhat higher than previous data reported from Alaska. Transfer coefficients for polonium-210 from caribou to wolf were near unity for many tissues. However, polonium-210 does not appear to cross the placenta in caribou. Further study includes lichen collections and collection of further caribou samples from the beverly herd in order to determine transfer from lichens to caribou in both the Baker Lake and Snowdrift areas in the Northwest Territories. (author). 26 refs., 3 tabs

  10. Transfer of the uranium decay products, polonium-210 and lead-210, through the lichen-caribou-wolf food chain in northern Canada (manuscript report)

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, P A [Sasatchewan Univ., Saskatoon (Canada). Biology Dept.

    1991-05-01

    The main purpose of this study is to investigate the accumulation and transfer of polonium-210 and lead-210 in the arctic food chain, lichen-caribou-wolf, in the Northwest Territories. Polonium-210 arises from lead-210 decay and is a widespread alpha-emitting radionuclide. It seeks soft tissue and has the potential to accumulate in the food chain. Caribou, wolves and other wildlife may become exposed to enhanced levels of these two uranium-series radionuclides if the proposed uranium mine near Baker Lake, Northwest Territories, proceeds. Baker Lake lies at the crossroads of the ranges of the Beverly, the Kaminuriak and the Wager Bay caribou herds. Therefore, it is important to establish baseline concentrations and natural food chain transfer of uranium series radionuclides, in this study. This information can be used for baseline data before any further mining development takes place. This study will also provide data regarding the statistical uncertainty attached to transfer coefficients. This can help ensure reliable and appropriate future monitoring of environmental change. With the participation of the hunters of Baker Lake, caribou and wolf samples were collected and analyzed for polonium. Results indicate that polonium-210 activity in caribou tissues were somewhat higher than previous data reported from Alaska. Transfer coefficients for polonium-210 from caribou to wolf were near unity for many tissues. However, polonium-210 does not appear to cross the placenta in caribou. Further study includes lichen collections and collection of further caribou samples from the beverly herd in order to determine transfer from lichens to caribou in both the Baker Lake and Snowdrift areas in the Northwest Territories. (author). 26 refs., 3 tabs.

  11. Analysis of prospecting effect of polonium survey and geoelectric survey extracted uranium and molybdenum in the south of Shengyuan volcanic basin

    International Nuclear Information System (INIS)

    Jin Hehai

    2007-01-01

    Polonium survey and geoelectric survey extracted uranium and molybdenum show that compound anomaly with sharp anomaly peak of the curve of polonium-210, uranium, molybdenum appears along many survey lines in Bakou area, Shengyuan volcanic basin, which may reflect the enrichment of uranium and molybdenum in rock formation and soil layer. By contrasting the anomaly curve to that above the buried uranium deposit, it is recognized that compound anomaly is closely related to the uranium mineralization condition in the area and some favourable sites for uranium metallogeny have been predicated. (authors)

  12. Bioaccumulation of polonium ({sup 210}Po) and uranium ({sup 234}U, {sup 238}U) in plants around phosphogypsum waste heap in Wislinka (northern Poland)

    Energy Technology Data Exchange (ETDEWEB)

    Borylo, A.; Skwarzec, B. [Gdansk Univ. (Poland). Faculty of Chemistry

    2011-07-01

    In the study the activities of polonium {sup 210}Po and uranium {sup 234}U, {sup 238}U in plants, collected near phosphogypsum waste heap in Wis'linka (northern Poland), were determined by using the alpha spectrometry. The obtained results revealed that the concentrations of {sup 210}Po, {sup 234}U, and {sup 238}U in the analyzed plants were differentiated. In the analyzed flora organisms the highest amounts of polonium and uranium were found in ruderal plant samples as well as willow samples (Salix viminalis) from protection zone of phosphogypsum waste heap. The concentrations of {sup 210}Po, {sup 234}U and {sup 238}U in the analyzed plants were higher in roots than in green parts of plants. The higher concentrations of {sup 210}Po and {sup 238}U radionuclides were estimated for hydrophyte (common sedge Carex nigra Reichard), the favourite habitat of which is particularly wet meadow and for plants collected in the vicinity of phosphogypsum waste heap. The major source of polonium and uranium in analyzed plants is root system. The values of {sup 234}U/ {sup 238}U activity ratio in all analyzed plants are closed to one, what indicated that source of uranium in analyzed plants is phosphogypsum. The highest uranium and polonium concentrations were characterized for plants, which are covered with tomentose. The comparability polonium and uranium contents were confirmed in edible plants, but higher accumulation was determined in ripe species than immature species of vegetables. The higher polonium and uranium concentrations were noticed in green parts of plant, the lower in roots. Polonium concentration in cultivated plants samples was not species diverse. Therefore, the significant source of polonium and uranium in analyzed plants is wet and dry atmospheric falls gathering the soil and air dust from phosphogypsum waste dump. The maximum {sup 210}Po and {sup 238}U radionuclides concentrations were found in green parts of red beet (Beta vulgaris esculenta), the

  13. A study of chemical forms of polonium-210 and lead-210 in air particulates in phosphate mines and Tartous port

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Al-Kharfan, K.; Khalili, H.; Hasan, M.

    2003-03-01

    Chemical forms of polonium-210 and lead-210 in air particulates of two areas having different climate conditions (Phosphate mines and Tartous port) have been studied. Air particulates were collected at six periods covering the climate changes from September 2000 until February 2002. Total suspended particulates (TSP) concentration was varied between 1827 and 9722 μg/M 3 and 197 and 1135 μg/m 3 in phosphate mines and Tartous port respectively; all of these values were higher than the maximum permissible concentration according to the Syrian standard (120 μg/m 3 ). Results of 210 po and 210 Pb extraction from the air particulates using selective solutions have shown that inorganic and insoluble 210 Po and 210 Pb (attached to silica and not soluble in mineral acids) ratio was high in phosphate mine air particulates and reached a value of 94% and 77% respectively. While the amount of lead 210 attached to organic compounds has reached a value of 24%. In addition, small variations in total inorganic and insoluble 210 Po and 210 Pb during the year were observed with little differences between polonium 210 ratio in both Tartous port and phosphate mines, which indicated that variations in climate conditions may affect the chemical forms. In both cases, inorganic and insoluble polonium 210 and lead 210 ratio was high; this may lead to their attachment to lung cells and their transfer via body streams. Moreover, the date obtained in this study can be utilized to calculate the radiation dose due to inhalation of radon gas and its decay daughters in the Syrian phosphate sites. (author)

  14. Individual monitoring conducted by the Health Protection Agency in the London polonium-210 incident

    International Nuclear Information System (INIS)

    Bailey, Michael; Birchall, Alan; Etherington, George; Wilkins, Bernard; Bishop, Louise; Fraser, Graham; Gross, Roger; Maguire, Helen; Evans, Barry; Shaw, Karen

    2008-01-01

    Mr. Alexander Litvinenko died on 23 November 2006, having allegedly been poisoned with polonium- 210 ( 210 Po) a few weeks earlier. The police investigation identified a number of contaminated locations, including parts of several hotels, restaurants, offices and transport. An extensive programme of individual monitoring of potentially exposed persons was rapidly initiated, based on urine sampling. Methods used for low-level measurement of 210 Po in environmental samples were adapted. The Health Protection Agency set a Reporting Level of 30 mBq d -1 , results above which indicated likely intake of 210 Po from the incident. At each location, risk assessments were undertaken to identify persons with significant risk of contamination with 210 Po. These individuals were invited to provide samples, not only to enable a direct assessment to be made of their own exposures, but also to inform decisions on whether others connected with the location should provide samples, or whether they could be reassured. Urine samples from 753 people were processed: about 500 during the first month. Of these, 139 measurements were above the Reporting Level, assessed doses for 36 were in the range ≥ 1 mSv and <6 mSv, and 17 were ≥ 6 mSv, with the highest at about 100 mSv. Many of the hotel guests were overseas visitors. An Overseas Advice Team was set up to encourage authorities abroad to adopt similar strategies. Overall, 664 persons from 52 countries and territories were identified. For 176, results of urine measurements were provided to the Overseas Advice Team, of which 13 were above the Reporting Level. Assessed doses for eight of these were <1 mSv, and the other five were in the range ≥ 1 mSv and <6 mSv. (author)

  15. Polonium-210 in dried fin fishes of Tuticorin, Southeast coast of India

    International Nuclear Information System (INIS)

    Carol, R.; Wesley, S.G.

    2013-01-01

    Tuticorin is one of the major sea-ports and fish-landing centres in the southeastern coast of India. Most of the fishes landed in this coast are consumed fresh and 40% of the fishes are used in the dried form. 210 Po (t 1/2 = 138.4 days) in marine food has received much interest from the scientific community because of its high toxicity and the radioactive dose it delivers to marine organisms and human beings when compared to anthropogenic radionuclides released into coastal waters. Although many studies have been conducted in fresh fishes from various coasts concerning 210 Po, sufficient data are not available for value-added dried marine fish products. In the present study, 210 Po and 210 Pb were quantified in some commercially important dried fishes and their exposure to humans studied. Polonium-210 was determined after wet digestion and counted using an alpha probe. Overall, the concentration of 210 Po in the dried fish muscle tissue ranged from 1.45 ± 0.82 to 559.23 ± 5.45 Bq kg -1 . The highest concentration in the muscle tissue was recorded for the species Stolephorus brevisensis (559.23 ± 8.9 Bq kg -1 ) belonging to the group Clupeidae and the lowest in Harpodon sp. (Bombay duck). The 210 Po dose receive by the public due to consumption of the dried fishes was found to be in the range of 25.2-350.3 μSV yr -1 and the fish samples were found to be radiologically safe. (author)

  16. Polonium-210 in cartilaginous fishes (Chondrichthyes) from south-eastern Australian waters

    International Nuclear Information System (INIS)

    Smith, D.J.; Towler, H.

    1993-01-01

    A study was made of the concentration of the naturally occurring radionuclide polonium-210 in the livers of cartilaginous fishes (chondrichthyans) caught in the waters of Port Phillip Bay, Victoria, Australia in 1991. Five elasmobranch species had 210 Po concentrations in the range 1-31 Bq kg -1 (wet weight) and one holocephalian species, the elephant fish (Callorhynchus milii), was exceptional with a 210 Po range of 60-270 Bq kg -1 (n-3, mean 180 Bq kg -1 ). Lead-210 was present at 0.1-1.1 Bq kg -1 and activity concentration ratios of 210 Po: 210 Pb were all greater than 1, indicating that the 210 Po could not all have grown in from in situ decay of 210 Pb within the chondrichthyan liver. The concentration of 210 Po in the livers appeared to be species related. Concentrations of the trace metals Cu, Fe and Zn showed no correlation with the 210 Po and were not species-related. The mean concentration of 210 Po measured in Port Phillip Bay water was 0.32 mBq kg -1 . This yields concentration factors of 3.2 x 10 3 to 8.4 x 10 5 for unsupported 210 Po in the livers of the chondrichthyans. The total 210 Po (using Q=20) exposes the livers to a weighted absorbed dose of up to 140 mGy year -1 (16 μGy h -1 ), which is >99% of the total internal dose and three orders of magnitude greater than the external dose based on estimated levels of 40 K. 18 refs., 3 tabs., 2 figs

  17. Polonium-210 accumulates in a lake receiving coal mine discharges-anthropogenic or natural?

    Science.gov (United States)

    Nelson, A W; Eitrheim, E S; Knight, A W; May, D; Wichman, M D; Forbes, T Z; Schultz, M K

    2017-02-01

    Coal is an integral part of global energy production; however, coal mining is associated with numerous environmental health impacts. It is well documented that coal-mine waste can contaminate the environment with naturally-occurring radionuclides from the uranium-238 ( 238 U) decay series. However, the behavior of the final radionuclide in the 238 U-series, i.e., polonium-210 ( 210 Po) arising from coal-mine waste-water discharge is largely unexplored. Here, results of a year-long (2014-2015) field study, in which the concentrations of 210 Po in sediments and surface water of a lake that receives coal-mine waste-water discharge in West Virginia are presented. Initial measurements identified levels of 210 Po in the lake sediments that were in excess of that which could be attributed to ambient U-series parent radionuclides; and were indicative of discharge site contamination of the lake ecosystem. However, control sediment obtained from a similar lake system in Iowa (an area with no coal mining or unconventional drilling) suggests that the levels of 210 Po in the lake are a natural phenomenon; and are likely unrelated to waste-water treatment discharges. Elevated levels of 210 Po have been reported in lake bottom sediments previously, yet very little information is available on the radioecological implications of 210 Po accumulation in lake bottom sediments. The findings of this study suggest that (Monthly Energy Review, 2016) the natural accumulation and retention of 210 Po in lake sediments may be a greater than previously considered (Chadwick et al., 2013) careful selection of control sites is important to prevent the inappropriate attribution of elevated levels of NORM in lake bottom ecosystems to industrial sources; and (Van Hook, 1979) further investigation of the source-terms and potential impacts on elevated 210 Po in lake-sediment ecosystems is warranted. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Death by polonium-210: lessons learned from the murder of former Soviet spy Alexander Litvinenko.

    Science.gov (United States)

    McFee, Robin B; Leikin, Jerrold B

    2009-02-01

    The medical response to radiation--whether the result of radiological warfare, terrorist deployment of improvised radiation dispersal weapons, political assassination, occupational or industrial accidents or the medically radiated patient remains one of the least taught among all disciplines within medical education. In the aftermath of 9/11 among medical vulnerabilities to toxicant threats, of all the categories of weapons of mass destruction (WMD)--whether using the CBRNE (chemical, biological, radiological, nuclear, explosive) or NBC (nuclear, biological, chemical) acronym--radiation is the least taught in professional schools, responder cultures or civil preparedness organizations. To date, few health care professionals (HCP) possess the fundamental knowledge or skills to identify and diagnose, let alone treat a radiation victim; this vulnerability made even more obvious in the aftermath of the high profile assassination of former Russian agent Alexander Litvinenko. He was poisoned with Polonium210. Radioactive substances are ubiquitous with radiation sources being in or transported through virtually every region nationwide. It is essential to increase preparedness among community and rural health care facilities as well as urban and university hospitals. Managing radiation injuries effectively requires access to specialized equipment and expertise. Radiation sickness is progressive and may require acute, critical and long-term care throughout the course of illness. Regardless of the source, preparedness rests upon acknowledging a threat exists and dedicating the resources to address the risks including the enhancement of training and equipment. Mass or individual exposures to radiation present unique challenges to the entire response continuum from law enforcement, first responders and emergency medical care. Increased education about and practice in responding to radiological threats is essential to enhance preparedness.

  19. Isospin degree of freedom in even-even 68-76Ge and 62-70Zn isotopes

    International Nuclear Information System (INIS)

    Jalili Majarshin, A.

    2018-01-01

    The introduction of isotopic spin is significant in light nuclei as Ge and Zn isotopes in order to take into account isospin effects on energy spectra. Dynamical symmetries in spherical, γ-soft limits and transition in the interacting boson model IBM-3 are analyzed. Analytic expressions and exact eigenenergies, electromagnetic transitions probabilities are obtained for the transition between spherical and γ-soft shapes by using the Bethe ansatz within an infinite-dimensional Lie algebra in light mass nuclei. The corresponding algebraic structure and reduction chain are studied in IBM-3. For examples, the nuclear structure of the 68-76 Ge and 62-70 Zn isotopes is calculated in IBM-3 and compared with experimental results. (orig.)

  20. Isospin degree of freedom in even-even 68-76Ge and 62-70Zn isotopes

    Science.gov (United States)

    Jalili Majarshin, A.

    2018-01-01

    The introduction of isotopic spin is significant in light nuclei as Ge and Zn isotopes in order to take into account isospin effects on energy spectra. Dynamical symmetries in spherical, γ-soft limits and transition in the interacting boson model IBM-3 are analyzed. Analytic expressions and exact eigenenergies, electromagnetic transitions probabilities are obtained for the transition between spherical and γ-soft shapes by using the Bethe ansatz within an infinite-dimensional Lie algebra in light mass nuclei. The corresponding algebraic structure and reduction chain are studied in IBM-3. For examples, the nuclear structure of the 68-76Ge and 62-70Zn isotopes is calculated in IBM-3 and compared with experimental results.

  1. Electric and magnetic dipole transitions from broad s-wave neutron resonance in even-even sd-shell nuclei

    International Nuclear Information System (INIS)

    Kitazawa, H.; Igashira, M.; Shimizu, M.; Muto, K.; Oda, T.; Achiha, Y.; Lee, Y.; Mukai, N.

    1992-01-01

    Observations have been performed for electromagnetic transitions from the broad s-wave neutron resonances at 658 keV in 24 Mg, at 180 keV in 28 Si, and at 103 keV in 32 S. Capture gamma rays were measured with an anti-Compton NaI(Tl) detector, using a neutron time-of-flight technique. E1 and M1 transitions from those resonances to low-lying states with a strong single-particle character were found. The deduced partial radiative widths for E1 transition are in excellent agreement with the Lane-Mughabghab valence-capture model calculations taking the neutron effective charge, -Ze/A. Moreover, it is shown that essential features of the observed E1 and M1 transitions can be well explained by assuming a configuration-mixing wave function, Ψ i (1/2 + )=a(0 + direct-product 1/2 + )+b(1 + direct-product 1/2 + )+c(1 + direct-product 3/2 + ), for each resonance. The M1 transition strengths are compared also with more detailed shell model calculations in the model space of full (sd) n configurations, using the Wildenthal effective interaction

  2. The Hartree-Fock approximation for s-d shell even-even nuclei with N different of Z

    International Nuclear Information System (INIS)

    Oliveira, P.C. de.

    1981-02-01

    Using the Hartree-Fock approximation method for 22 Ne, 26 Mg and 30 Si nuclei with different kinds of two-body interactions, the electric quadrupole moments and projected energy levels, of angular momentum J=0,2,4,6..., are determined. The Peierls-Yoccoz projection m ethod is used to determine the wave function with well-defined angular momentum. A comparison is made, with the experimental results and the ones obtained by other authors. (Author) [pt

  3. Study of neutron shell structure of even-even 40-56Ca isotopes by the dispersive optical model

    International Nuclear Information System (INIS)

    Bespalova, O.V.; Boboshin, I.N.; Varlamov, V.V.; Ermakova, T.A.; Ishkhanov, B.S.; Romanovskij, E.A.; Spasskaya, T.I.; Timokhina, T.P.

    2005-01-01

    The single-particle energies and occupation probabilities of the bound neutron states in 40,42,44,46,48 Ca isotopes were obtained by the joint evaluation of the stripping and pick-up reaction data. The results were analyzed by the dispersive optical model and a good agreement was achieved. The dispersive optical potential was extrapolated to unstable 50,52,54,56 Ca nuclei. The calculated single-particle energies of the bound neutron states in unstable Ca isotopes were compared with the nuclear shell-model calculations, which predicted new magic number N = 34 for nuclei with Z = 20 [ru

  4. Decay out of the yrast and excited highly-deformed bands in the even-even nucleus {sup 134}Nd

    Energy Technology Data Exchange (ETDEWEB)

    Petrache, C.M.; Bazzacco, D.; Lunardi, S. [Sezione di Padova (Italy)] [and others

    1996-12-31

    The resolving power achieved by the new generation of {gamma}-ray detector arrays allows now to observe transitions with intensities of the order of {approximately}10{sup {minus}3} of the population of the final residual nucleus, making therefore feasible the study of the very weakly populated excited bands built on the superdeformed (SD) minimum or of the decay out of the SD bands. As a matter of fact, numerous excited SD bands have been observed in the different regions of superdeformation, which led to a deeper understanding of the single-particle excitation in the second minimum. The first experimental breakthrough in the study of the decay out process has been achieved in the odd-even {sup 133,135}Nd nuclei of the A=130 mass region. There, the observation of the discrete linking transitions has been favored by the relatively higher intensity of the highly-deformed (HD) bands ({approximately}10%), as well as by the small excitation energy with respect to the yrast line in the decay-out region ({approximately}1 MeV). No discrete linking transitions have been so far observed in the A=80, 150 mass regions. The present results suggest that the decay out of the HD bands in {sup 134}Nd is triggered by the crossing with the N=4 [402]5/2{sup +} Nilsson orbital, that has a smaller deformation than the corresponding N=6 intruder configuration. The crossing favours the mixing with the ND rotational bands strongly enhancing the decay-out process and weakening the in-band transition strength. The HD band becomes fragmented and looses part of its character. The intensity of the decay-out transitions increases when the spin of the HD state decreases, indicating enhanced ND amplitude in the wavefunction when going down the band. Lifetime measurements of the HD bands are crucial to further elucidate the decay-out process.

  5. The reduced transition probabilities for excited states of rare-earths and actinide even-even nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Ghumman, S. S. [Department of Physics, Sant Longowal Institute of Engineering and Technology (Deemed University), Longowal, Sangrur-148106, Punjab, India s-ghumman@yahoo.com (India)

    2015-08-28

    The theoretical B(E2) ratios have been calculated on DF, DR and Krutov models. A simple method based on the work of Arima and Iachello is used to calculate the reduced transition probabilities within SU(3) limit of IBA-I framework. The reduced E2 transition probabilities from second excited states of rare-earths and actinide even–even nuclei calculated from experimental energies and intensities from recent data, have been found to compare better with those calculated on the Krutov model and the SU(3) limit of IBA than the DR and DF models.

  6. Isospin degree of freedom in even-even {sup 68-76}Ge and {sup 62-70}Zn isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Jalili Majarshin, A. [University of Tabriz, Department of Physics, Tabriz (Iran, Islamic Republic of)

    2018-01-15

    The introduction of isotopic spin is significant in light nuclei as Ge and Zn isotopes in order to take into account isospin effects on energy spectra. Dynamical symmetries in spherical, γ-soft limits and transition in the interacting boson model IBM-3 are analyzed. Analytic expressions and exact eigenenergies, electromagnetic transitions probabilities are obtained for the transition between spherical and γ-soft shapes by using the Bethe ansatz within an infinite-dimensional Lie algebra in light mass nuclei. The corresponding algebraic structure and reduction chain are studied in IBM-3. For examples, the nuclear structure of the {sup 68-76}Ge and {sup 62-70}Zn isotopes is calculated in IBM-3 and compared with experimental results. (orig.)

  7. Low-lying magnetic dipole strength distribution in the γ-soft even-even 130-136Ba

    International Nuclear Information System (INIS)

    Guliyev, E.; Ertugral, F.; Kuliev, A.A.

    2006-01-01

    In this study the scissors mode 1 + states are systematically investigated within the rotational invariant Quasiparticle Random Phase Approximation (QRPA) for 130-136 Ba isotopes. We consider the 1 + vibrations generated by the isovector spin-spin interactions and the isoscalar and isovector quadrupole-type separable forces restoring the broken symmetry by a deformed mean field according to A.A. Kuliev et al. (Int. J. Mod. Phys. E 9, 249 (2000)). It has been shown that the restoration of the broken rotational symmetry of the Hamiltonian essentially decreases the B(M1) value of the low-lying 1 + states and increases the collectivization of the scissors mode excitations in the spectroscopic energy region. The agreement between the calculated mean excitation energies as well as the summed B(M1) value of the scissors mode excitations and the available experimental data of 134 Ba and 136 Ba is rather good. A destructive interference between the orbit and spin part of the M1 strength has been found for barium isotopes near the shell closer. For all the nuclei under investigation, the low-lying M1 transitions have ΔK=1 character as it is the case for the well-deformed nuclei. (orig.)

  8. Calculations of the Low-Lying Structures in the Even-Even Nd/Sm/Gd/Dy Isotopes

    Science.gov (United States)

    Lee, Su Youn; Lee, J. H.; Lee, Young Jun

    2018-05-01

    The nuclear structure of deformed nuclei has been studied using the interacting boson model (IBM). In this study, energy levels and E2 transition probabilities were determined for even nuclei in the Nd/Sm/Gd/Dy chains which have a transition characteristic between the rotational, SU(3) and vibrational, U(5) limits. The structure of the nuclei exhibits a slight breaking of the SU(3) symmetry in the direction of U(5), and therefore, we add the d-boson number operator n d , which is the main term of the U(5) symmetric Hamiltonian, to the SU(3) Hamiltonian of the IBM. The calculated results for low-lying energy levels and E2 transition rates in Nd/Sm/Gd/Dy isotopes are in reasonably good agreement with known experimental results.

  9. Theoretical estimates of supernova-neutrino cross sections for the stable even-even lead isotopes: Charged-current reactions

    Science.gov (United States)

    Almosly, W.; Carlsson, B. G.; Suhonen, J.; Toivanen, J.; Ydrefors, E.

    2016-10-01

    A detailed study of the charged-current supernova electron neutrino and electron antineutrino scattering off the stable even-mass lead isotopes A =204 , 206, and 208 is reported in this work. The proton-neutron quasiparticle random-phase approximation (pnQRPA) is adopted to construct the nuclear final and initial states. Three different Skyrme interactions are tested for their isospin and spin-isospin properties and then applied to produce (anti)neutrino-nucleus scattering cross sections for (anti)neutrino energies below 80 MeV. Realistic estimates of the nuclear responses to supernova (anti)neutrinos are computed by folding the computed cross sections with a two-parameter Fermi-Dirac distribution of the electron (anti)neutrino energies. The computed cross sections are compared with earlier calculations and the analyses are extended to take into account the effects coming from the neutrino oscillations.

  10. Neutron densities and the single particle structure of several even-even nuclei from 40Ca to 208Pb

    International Nuclear Information System (INIS)

    Ray, L.; Hodgson, P.E.

    1979-01-01

    Previously developed techniques which sum the squares of proton single particle wave functions to obtain nuclear charge densities are applied to the study of neutron distributions in /sup 40,48/Ca, /sup 58,64/Ni, /sup 116,124/Sn, and 208 Pb by comparing to those neutron densities deduced from 800 MeV proton elastic scattering data. The proton and neutron single particle wave functions are derived from a one-body, nonlocal Woods-Saxon binding potential whose parameters are adjusted to give the experimental single particle energies. Empirical spectroscopic factors determine the appropriate occupation probabilities for the single particle levels near the Fermi surface. Proper attention is given to nonorthogonality problems and to the removal of the spurious center-of-mass motion. These semiphenomenological neutron densities are compared to the predictions of the density matrix expansion variant of Hartree-Fock theory and to densities which are empirically deduced from recent 800 MeV polarized proton elastic scattering data. These ''experimental'' neutron distributions are obtained from approximate second order Kerman, McManus, and Thaler optical potential analyses using essentially ''model independent'' neutron densities. Qualitatively good agreement is obtained between the semiphenomenological neutron densities computed here, the density matrix expansion predictions, and the empirical results

  11. Microscopic study of low-lying yrast spectra and deformation systematics of even-even barium isotopes

    International Nuclear Information System (INIS)

    Sarswat, S.P.; Bharti, Arun; Khosa, S.K.

    1996-01-01

    The yrast spectra has been obtained in the variation-after-projection framework using pairing-plus-quadrupole- quadrupole model for the two body interaction. Besides the low-lying yrast spectra, the calculated values of intrinsic quadrupole moments of some of the barium isotopes i.e. 124-134 Ba are presented

  12. Hydrodynamic model wavefunctions in intrinsic coordinates and their application to the structure of even-even nuclei

    International Nuclear Information System (INIS)

    Margetan, F.J.

    1979-01-01

    A closed expression is presented for intrinsic-coordinate (β, γ, theta/sub i/) eigenfunctions of the hydrodynamic, quadrupole-vibration Hamiltonian of A. Bohr. These functions are used as an expansion basis for the treatment of more general collective Hamiltonians. Two classes of such Hamiltonians are considered. In each the potential energy term of the Bohr Hamiltonian, 1/2 Cβ 2 , was replaced with a more general function of the shape coordinates, V(β, γ). The potential of Gneuss and Greiner (1) is used to demonstrate the soundness of the calculational techniques, and to illustrate convergence properties of calculated energies. Potentials possessing a single minimum on 0 less than or equal to γ less than or equal to 60 0 are considered through the study of a quadratic-potential [QP] Hamiltonian. The smooth development from spherical to asymmetrically deformed nuclear shapes is investigated by systematically varying the parameters β 0 and C/sub γ/. Model energies and E2 transition rates are traced during this process. The QP model is then applied to 106 Pd, 166 Er, 182 W, 122 Te, and 186 188 190 192 Os. Low-energy γ vibrations appear to play a prominent role in the latter five nuclei, and the QP model offers a better accounting of experimental spectra than does the model of Davydov and Chaban (2). 74 references

  13. Natural levels of lead-210, polonium-210 and radium-226 in humans and biota of the Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Holtzman, R B

    1966-06-11

    Relatively high concentrations of some fission products in humans and biota from Lapland and Alaska have been reported. These have been attributed to the continual accumulation of those products on the long-lived, slow-growing Arctic lichens and sedges. Such plants are an important source of forage for reindeer and caribou, the meat of which, in turn, constitutes a substantial portion of the diets of Laplanders and Eskimos. These high levels of fall-out suggest, together with the proposed mechanism of uptake and the similarities to strontium-90 in atmospheric distribution and biochemistry, that in Arctic biota, the naturally occurring airborne nuclides lead-210 and its decay product, polonium-210, may also be present in high concentration. These naturally occurring fall-out activities are of special interest in studies of aerosol precipitation mechanisms because their levels are independent of bomb tests and consequently they have been constant over the years. Because of this constancy and the high energy of the particles emitted by the lead-210 series (a 5.3-MeV ..cap alpha..-particle from polonium-210 and a 0.4-MeV (average energy) ..beta..-particle from bismuth-210 compared with ..beta..-rays with average energies of 0.4 MeV from cesium-137 and 1.1 MeV from strontium-90 (yttrium-90)), the radiation dose to Arctic biota from this source may be quite significant relative to that from artificial ones. 24 references.

  14. Transfer factor of Radium -226, lead-210 and Polonium-210 from Norm contaminated soil to Atriplex, Afelfa and Bermuda grasses

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Mukhallati, H.; Al-Hamwi, A.

    2011-10-01

    transfer factors of Radium -226, lead-210 and Polonium-210 from contaminated soil with oil coproduced water to grazing plants in the north eastern region of Syria have been determined. contaminated soil was collected from one of the AL-Furat Petroleum Oil company oil fields;soil was distributed into several pots where the studied plants were planted in order to study the transfer factors of radioisotopes to them. Results have shown that the mean transfer factors of radium to green parts have reached has reached 0.0016 in Atriplex halimus L.,0.0021 in Atriplex canescens Nutt, 0.0025 in Atriplex Leucoclada Bioss,0.0082 in Bermuda grass and 0.0167 in Medicago Sativ L,which was the highest,while the transfer factors of polonium and lead were ten times higher than those for radium and reacted 0.012 in Atriplex Leucoclada Bioss, 0.011 in Atriplex canescens Nutt, 0.007 in Atriplex halimus L.0.32 in bermuda grass and 0.025 in Afelfa.(author)

  15. Use of the transpiration method to study polonium evaporation from liquid lead-bismuth eutectic at high temperature

    International Nuclear Information System (INIS)

    Prieto, Borja Gonzalez; Lim, Jun; Rosseel, Kris; Bosch, Joris van den; Aerts, Alexander; Martens, Johan; Rizzi, Matthias; Neuhausen, Joerg

    2014-01-01

    Qualitative and quantitative understanding of Po volatilization under different conditions is of key importance for safety assessments of lead-bismuth eutectic (LBE) based nuclear reactors, spallation targets and accelerator driven systems. In this work we explore the possibilities of the transpiration method in combination with simple models to study the equilibrium and kinetics of Po evaporation from highly diluted solutions in lead-bismuth eutectic between 600 and 1000 C in Ar/5% H 2 and Ar. On the basis of evaporation experiments at various carrier gas flow rates, we identified the conditions of vapor saturation allowing the determination of equilibrium constants. From the limiting behavior at high flow rates, values for the maximal evaporation rate of Po from LBE were estimated. Measurements of evaporation as a function of time were consistent with the assumption that polonium dissolved in LBE obeys Henry's law. A theoretical analysis furthermore suggested that diffusion of polonium in LBE was not a rate limiting factor for evaporation under vapor saturation conditions. Newly determined values for the Henry constant of Po in LBE between 600 and 1000 C were consistent with previously derived correlations.

  16. Transfer of the uranium decay products, polonium-210 and lead-210, through the lichen-cariboo-wolf food chain in northern Canada. Manuscript report No. MR18-91

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, P A

    1991-01-01

    Study to investigate the accumulation and transfer of polonium-210 and lead-210 in the Arctic food chain lichen-caribou-wolf in the Northwest Territories. With the participation of the hunters of Baker Lake, caribou and wolf samples were collected and analyzed for polonium. The level of polonium-210 was determined in lichen, several caribou tissues, and several wolf tissues. Transfer coefficients were derived between trophic levels in the food chain and the Po-210:PB-210 ratios for lichens and selected tissues in caribou and wolf were determined.

  17. The laboratory books of Pierre and Marie Curie. Note proposed to the Sciences Academy on july the 18. of the year 1898 and the polonium discovery

    International Nuclear Information System (INIS)

    Adloff, J.P.

    1998-01-01

    Chemical research on radioactivity started in 1898. That year, a note was presented by the Curies on the discovery of a new radioactive material contained in pechblende and called ''polonium''. The different steps of the discovery and the experiments carried out are related as well as the surprises, the questioning and the doubts of the Curies in the years immediately following. (O.M.)

  18. Study of proton and 2 protons emission from light neutron deficient nuclei around A=20; Etude de l'emission proton et de deux protons dans les noyaux legers deficients en neutrons de la region A=20

    Energy Technology Data Exchange (ETDEWEB)

    Zerguerras, T

    2001-09-01

    Proton and two proton emission from light neutron deficient nuclei around A=20 have been studied. A radioactive beam of {sup 18}Ne, {sup 17}F and {sup 20}Mg, produced at the Grand Accelerateur National d'Ions Lourds by fragmentation of a {sup 24}Mg primary beam at 95 MeV/A, bombarded a {sup 9}Be target to form unbound states. Proton(s) and nuclei from the decay were detected respectively in the MUST array and the SPEG spectrometer. From energy and angle measurements, the invariant mass of the decaying nucleus could be reconstructed. Double coincidence events between a proton and {sup 17}F, {sup 16}O, {sup 15}O, {sup 14}O and {sup 18}Ne were registered to obtain excitation energy spectra of {sup 18}Ne, {sup 17}F, {sup 16}F, {sup 15}F et {sup 19}Na. Generally, the masses measures are in agreement with previous experiments. In the case of {sup 18}Ne, excitation energy and angular distributions agree well with the predictions of a break up model calculation. From {sup 17}Ne proton coincidences, a first experimental measurement of the ground state mass excess of {sup 18}Na has been obtained and yields 24,19(0,15)MeV. Two proton emission from {sup 17}Ne and {sup 18}Ne excited states and the {sup 19}Mg ground state was studied through triple coincidences between two proton and {sup 15}O, {sup 16}O and {sup 17}Ne respectively. In the first case, the proton-proton relative angle distribution in the center of mass has been compared with model calculation. Sequential emission from excited states of {sup 17}Ne, above the proton emission threshold, through {sup 16}F is dominant but a {sup 2}He decay channel could not be excluded. No {sup 2}He emission from the 1.288 MeV {sup 17}Ne state, or from the 6.15 MeV {sup 18}Ne state has been observed. Only one coincidence event between {sup 17}Ne and two proton was registered, the value of the one neutron stripping reaction cross section of {sup 20}Mg being much lower than predicted. (author)

  19. Study of proton and 2 protons emission from light neutron deficient nuclei around A=20; Etude de l'emission proton et de deux protons dans les noyaux legers deficients en neutrons de la region A=20

    Energy Technology Data Exchange (ETDEWEB)

    Zerguerras, T

    2001-09-01

    Proton and two proton emission from light neutron deficient nuclei around A=20 have been studied. A radioactive beam of {sup 18}Ne, {sup 17}F and {sup 20}Mg, produced at the Grand Accelerateur National d'Ions Lourds by fragmentation of a {sup 24}Mg primary beam at 95 MeV/A, bombarded a {sup 9}Be target to form unbound states. Proton(s) and nuclei from the decay were detected respectively in the MUST array and the SPEG spectrometer. From energy and angle measurements, the invariant mass of the decaying nucleus could be reconstructed. Double coincidence events between a proton and {sup 17}F, {sup 16}O, {sup 15}O, {sup 14}O and {sup 18}Ne were registered to obtain excitation energy spectra of {sup 18}Ne, {sup 17}F, {sup 16}F, {sup 15}F et {sup 19}Na. Generally, the masses measures are in agreement with previous experiments. In the case of {sup 18}Ne, excitation energy and angular distributions agree well with the predictions of a break up model calculation. From {sup 17}Ne proton coincidences, a first experimental measurement of the ground state mass excess of {sup 18}Na has been obtained and yields 24,19(0,15)MeV. Two proton emission from {sup 17}Ne and {sup 18}Ne excited states and the {sup 19}Mg ground state was studied through triple coincidences between two proton and {sup 15}O, {sup 16}O and {sup 17}Ne respectively. In the first case, the proton-proton relative angle distribution in the center of mass has been compared with model calculation. Sequential emission from excited states of {sup 17}Ne, above the proton emission threshold, through {sup 16}F is dominant but a {sup 2}He decay channel could not be excluded. No {sup 2}He emission from the 1.288 MeV {sup 17}Ne state, or from the 6.15 MeV {sup 18}Ne state has been observed. Only one coincidence event between {sup 17}Ne and two proton was registered, the value of the one neutron stripping reaction cross section of {sup 20}Mg being much lower than predicted. (author)

  20. Uranium, radon-222 and polonium-210 in drinking waters from metropolitan area of Recife, PE, Brazil

    International Nuclear Information System (INIS)

    Silva, Cleomacio Miguel da

    2000-04-01

    There is only scarce information on the presence of radionuclides in water for public consumption in Brazil. A recently issued federal regulation requires that waters from public supplies be screened to determine their content of alpha and beta emitters. In order to comply with this requirement the present work was carried out with the purpose of determining the concentration of natural uranium, 222 Rn and 210 Po in water supplies in the metropolitan region of Recife, Brazil. The analyses were performed in 17 points of supply of superficial water and 94 points of groundwater supply. The concentrations of uranium were determined by the fluorimetric method, whereas the liquid scintillation method was used to determine the concentration of 222 Rn. Polonium-210, on the other hand, was determined by alpha spectrometry, following its spontaneous deposition on copper disks. The water analyzer presented uranium concentrations varying from 35.3 to 1146.5 mBq/L for superficial resources and from 20.2 to 919.15 mBq/L for underground sources. The concentration of uranium in superficial water showed significant correlation with some parameters such as conductivity, alkalinity and total hardness, as well as, with the concentrations of Ca, Mg, Cl, K, SO 4 and Mn. No correlation, however, was shown with the concentrations of Fe, NO 2 and NO 3 . The concentrations of 222 Rn varied from 5.3 to 83.7 Bq/L in the groundwater analyzer. Radon concentration was not measured in superficial water due to the high emanation rate of radon in open air conditions. As far as 210 Po is concerned, the analyses showed concentrations ranging from 210 Po did not show and correlation with physico-chemical parameters. The average concentrations of uranium and 210 Po in superficial water were of 44.7 mBq/L, respectively. These values correspond to effective doses of 5.8 x 10 -4 mSv/yr and 4.5 x 10 -2 mSv/yr, for uranium and 210 Po, respectively. The average values for the concentrations of uranium, 222

  1. Ingestion of polonium ((210)Po) via dietary sources in high background radiation areas of south India.

    Science.gov (United States)

    Arunachalam, Kantha Deivi; Baskaran, Kamesh Viswanathan; Rao, D D; Sathyapriya, R; Annamalai, Sathesh Kumar; Kuruva, Jaya Krishna; Hari, Shanmugamsundaram

    2014-10-01

    To study the distribution of Polonium ((210)Po) activity in dietary sources in the high background radiation zone of Puttetti in southern Tamil Nadu. (210)Po was analyzed in the food materials consumed by the male and female individual representatives living in the high background areas by 24-h Duplicate Diet Study (DDS) and Market Basket Study (MBS). The MBS was performed by collecting the food samples such as, cereals, fruits, leafy vegetables, roots and tubers, other vegetables, fish, meat and milk grown in the high background radiation zone of southern Tamil Nadu as a part of baseline study in this region. The DDS was done by collecting the food materials consumed including the beverages in 24 h from different age groups of male and female individuals living in the village of Puttetti. The intake and ingestion dose of the radionuclide (210)Po was estimated. The average concentration of (210)Po in DDS (n = 33) was found to be 74 mBq.kg(- 1) of fresh weight. The MBS was collected based on food consumption representing more than 85-95% of annual supply, and were divided into eight food groups. The average concentration of (210)Po in the eight food groups namely leafy vegetables was 2176 mBq.kg(- 1) (n = 3), vegetables 55 mBq.kg(- 1) (n = 10), roots and tubers 251 mBq.kg(- 1) (n = 4), fruits 65 mBq.kg(- 1) (n = 5), fish 345 mBq.kg(- 1) (n = 2), meat food 117 mBq.kg(- 1) (n = 3), milk 20 mBq.kg(- 1) (n = 1) and cereal 290 (n = 1) mBq.kg(- 1) of fresh weight, respectively. The annual intake and ingestion dose due to (210)Po was estimated by DDS and MBS in adults, adolescents and children. The overall results showed that the MBS was moderately higher than the DDS in all age groups. Moreover, a DDS approach may even be more realistic, as cooked foodstuffs are used for dietary exposure assessment. The study confirms that the current levels of (210)Po do not pose a significant radiological risk to the local inhabitants.

  2. Polonium-210: the challenges in advising the law enforcement community during the investigation into the death of Alexander Litvinenko

    International Nuclear Information System (INIS)

    Cairns, James M.

    2008-01-01

    Full text: The death of Alexander Litvinenko in November 2006 delivered unique challenges for the radiological protection of emergency responders. The need to identify a cause of death and investigate a potential crime balanced against the need for the radiological safety of both the investigator staff and protection of the public led to a number of situations requiring unique solutions. Polonium 210 is a naturally occurring radioactive substance that appears as part of the uranium-235 decay series. It has a 138 day half-life with a specific activity of 1.66 x 10 14 Bq/g. It is considered for radiological purposes as an alpha emitter though it does have a low probability ( 4 Bq and ingestion of 6.7 x 10 3 Bq meaning that physical quantities of less than 1 μg are lethal. The first blood and urine samples from Mr Litvinenko were analysed by the author and his team who identified a 803 keV peak from gamma spectral analysis. After discussions with medical staff and the Senior Investigation Officer, an additional sample was taken to permit the completion of more detailed analytical techniques specifically for polonium-210. Using liquid scintillation counting and alpha spectrometry on the additional urine sample led to an estimated body burden within 10% of the final assessed intake from post-mortem samples. The investigation raised the following challenges to the author and Law Enforcement Personnel: a) Tracing the movement of the victim and his associates to; piece together a potential point and route of intake; and identify potential contamination areas requiring public protection measures by health agencies; b) Collection of evidence in a contaminated environment; c) Processing of contaminated forensics samples; d) Undertaking a post-mortem in a mortuary not designed for the processing of radiologically contaminated personnel; e) Identifying routes for obtaining polonium-210 including a review of historical papers from the UK, US and Russian early nuclear weapon

  3. Induction of the lambda bacteriophage synthesis in Escherichia coli K 12 by polonium alpha rays; Induction de la synthese du bacteriophage lambda chez Escherichia coli K 12 par les rayons alpha du polonium

    Energy Technology Data Exchange (ETDEWEB)

    Devoret, Raymond

    1958-06-15

    This research thesis reports the study of the inducing action of polonium alpha radiations in Escherichia Coli K 12 by using an external irradiation device. This work comprised the development of a method to spread bacteria in layer with a thickness less than 20 microns, and the measurement of the number of α particles falling on the irradiated surface. This measurement has been performed by using a nuclear emulsion and a simple photographic film. It appears that alpha radiations have an inducing action, and that at most 15 per cent of bacteria can be induced. The comparison of the induction curve with the survival curves of lysogen and sensitive stains shows that there is no abortive induction. Thus, it appears that this inducing action is not due to an indirect effect of the irradiated medium [French] Dans ce travail on a etudie l'action inductrice des rayons alphas du polonium chez Escherichia Coli K 12 par un diapoaitif d'irradiation externe. Son utilisation necessitait: - une methode d'etalement des bacteries en couche de moins de 20 microns d'epaisseur; - une mesure du nombre des particules alpha tombant sur la surface etendue irradiee. Les mesures ont ete faites a l'aide d'une emulsion nucleaire et d'un film photographique ordinaire. 1) Les rayons alphas ont une action inductrice. Au plus 15 pc des bacteries peuvent etre induites. 2) La oomparaison de la courbe d'induction et des courbes de survie des souches lysogene et sensible montre qu'il n'y a pas d'inductions abortives. 3) Cette action inductrice n'est pas due a un effet indirect du milieu irradie. (auteur)

  4. Elementary analyses in behalf of the project: Orientating investigation to Polonium-210 and other radionuclides in Dutch aquatic ecosystems

    International Nuclear Information System (INIS)

    Hart, M.J. 't; Breugem, P.M.; Koester, H.W.

    1989-11-01

    In this report, results of the determinations of total, organic and inorganic carbon analysis are reported for the project 'Orientating investigations of Polonium-210 and other natural radionuclides in Dutch aquatic ecosystems', projectnumber 248476. The method used is a modification of the method described by Froelich and is based on elemental analysis. Sediment samples from several locations of sea and river water show a large variation of the carbon content. The organic carbon concentration varies from 2.78 to 22.42 percent; the inorganic carbon varies from 1.25 to 5.66 percent. The analyses were run in duplicate with a mean standard deviation of 0.1 percent. (author). 4 refs.; 5 figs.; 7 tabs

  5. Studies on Polonium-210 and Lead-210 aspects in a near shore coastal environment at Kalpakkam, Tamilnadu, India

    International Nuclear Information System (INIS)

    Iyengar, M.A.R.

    2013-01-01

    In the present study, an attempt has been made to summarize the findings from a comprehensive research investigation, related to polonium-210 and lead-210 aspects in a confined near shore coastal marine environment at the site of Kalpakkam nuclear complex. The site hosts some major nuclear installations, the main units being a nuclear power station, fast breeder reactor units, reprocessing facilities and supporting facilities. These investigation have been carried out to evaluate the natural radiation exposures of the resident human population in the neighbourhood of the site complex, and compute the additional potential doses to the community, arising from operation of nuclear facilities. An added significance, surfaced during the study, was the presence of a higher natural radiation background in the study area, due to the occurrence of monazite - a thorium mineral - bearing beach sands in vast stretches of the coastal areas

  6. Polonium (210Po) and uranium (234U, 238U) in water, phosphogypsum and their bioaccumulation in plants around phosphogypsum waste heap at Wislinka (nothern Poland)

    International Nuclear Information System (INIS)

    Skwarzec, B.; Borylo, A.; Kosinska, A.; Radzajewska, S.

    2010-01-01

    The principal sources of polonium and uranium radionuclides the Wislinka area waste dump are phosphorites and phosphogypsum produced by the Phosphoric Fertilizers Industry of Gdansk. The values of uranium and polonium concentration in water with immediate surroundings of waste heap are considerably higher than in the waters of the Martwa Wisla river. The activity ratio 234 U/ 238 U is approximately about one in the phosphogypsum (0.97±0.06 and 0.99±0.04) and in the water of a retention reservoir and a pumping station (0.92±0.01 and 0.99±0.04), while in the water from the Martwa Wisla river is slightly higher than one (1.00±0.07 and 1.06±0.02). The leaching process of uranium and polonium from the phosphogypsum waste heap is responsible for the maximum uranium concentration (1097±6 μg·dm -3 and 1177±6 μg·dm -3 ) and the high 210 Po concentration (131.4±0.9 mBq·dm -3 and 165.7±1.4 mBq·dm -3 ) in the retention reservoir. The major source of polonium and uranium in plants are wet and dry atmospheric falls gathering soil and air dust from the phosphogypsum waste dump and root system. The highest uranium and polonium concentrations were found in older part of grasses (yellow oatgrass, meadow foxtail, moneywort), exposed to atmospheric falls for a long time. The maximum concentrations of 210 Po were characterized for samples of plant root collected at the retention reservoir (150.50±4.97 and 108.55±3.95 Bq·kg -1 dry mass). Polonium and uranium concentrations in water samples of the Martwa Wisla river are relatively low in comparison with the value in the retention reservoir and pumping station near the phosphogypsum waste heap. This suggests that the radionuclides could be leached from the dumping site to the surrounding environment. (authors)

  7. Sequential extraction procedure for determination of uranium, thorium, radium, lead and polonium radionuclides by alpha spectrometry in environmental samples

    Science.gov (United States)

    Oliveira, J. M.; Carvalho, F. P.

    2006-01-01

    A sequential extraction technique was developed and tested for common naturally-occurring radionuclides. This technique allows the extraction and purification of uranium, thorium, radium, lead, and polonium radionuclides from the same sample. Environmental materials such as water, soil, and biological samples can be analyzed for those radionuclides without matrix interferences in the quality of radioelement purification and in the radiochemical yield. The use of isotopic tracers (232U, 229Th, 224Ra, 209Po, and stable lead carrier) added to the sample in the beginning of the chemical procedure, enables an accurate control of the radiochemical yield for each radioelement. The ion extraction procedure, applied after either complete dissolution of the solid sample with mineral acids or co-precipitation of dissolved radionuclide with MnO2 for aqueous samples, includes the use of commercially available pre-packed columns from Eichrom® and ion exchange columns packed with Bio-Rad resins, in altogether three chromatography columns. All radioactive elements but one are purified and electroplated on stainless steel discs. Polonium is spontaneously plated on a silver disc. The discs are measured using high resolution silicon surface barrier detectors. 210Pb, a beta emitter, can be measured either through the beta emission of 210Bi, or stored for a few months and determined by alpha spectrometry through the in-growth of 210Po. This sequential extraction chromatography technique was tested and validated with the analysis of certified reference materials from the IAEA. Reproducibility was tested through repeated analysis of the same homogeneous material (water sample).

  8. Primate polonium metabolic models and their use in estimation of systemic radiation doses from bioassay data. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, N. [New York Univ. Medical Center, Tuxedo, NY (United States). Dept. of Environmental Medicine

    1989-03-15

    A Polonium metabolic model was derived and incorporated into a Fortran algorithm which estimates the systemic radiation dose from {sup 210}Po when applied to occupational urine bioassay data. The significance of the doses estimated are examined by defining the degree of uncertainty attached to them through comprehensive statistical testing procedures. Many parameters necessary for dosimetry calculations (such as organ partition coefficients and excretion fractions), were evaluated from metabolic studies of {sup 210}Po in non-human primates. Two tamarins and six baboons were injected intravenously with {sup 210}Po citrate. Excreta and blood samples were collected. Five of the baboons were sacrificed at times ranging from 1 day to 3 months post exposure. Complete necropsies were performed and all excreta and the majority of all skeletal and tissue samples were analyzed radiochemically for their {sup 210}Po content. The {sup 210}Po excretion rate in the baboon was more rapid than in the tamarin. The biological half-time of {sup 210}Po excretion in the baboon was approximately 15 days while in the tamarin, the {sup 210}Po excretion rate was in close agreement with the 50 day biological half-time predicted by ICRP 30. Excretion fractions of {sup 210}Po in the non-human primates were found to be markedly different from data reported elsewhere in other species, including man. A thorough review of the Po urinalysis procedure showed that significant recovery losses resulted when metabolized {sup 210}Po was deposited out of raw urine. Polonium-210 was found throughout the soft tissues of the baboon but not with the partition coefficients for liver, kidneys, and spleen that are predicted by the ICRP 30 metabolic model. A fractional distribution of 0.29 for liver, 0.07 for kidneys, and 0.006 for spleen was determined. Retention times for {sup 210}Po in tissues are described by single exponential functions with biological half-times ranging from 15 to 50 days.

  9. Polonium (²¹⁰Po), uranium (²³⁴U, ²³⁸U) isotopes and trace metals in mosses from Sobieszewo Island, northern Poland.

    Science.gov (United States)

    Boryło, Alicja; Nowicki, Waldemar; Olszewski, Grzegorz; Skwarzec, Bogdan

    2012-01-01

    The activity of polonium (210)Po and uranium (234)U, (238)U radionuclides, as well as trace metals in mosses, collected from Sobieszewo Island area (northern Poland), were determined using the alpha spectrometry, AAS (atomic absorption spectrometry) and OES-ICP (atomic emission spectrometry with inductively coupled plasma). The concentrations of mercury (directly from the solid sample) were determined by the cold vapor technique of CV AAS. The obtained results revealed that the concentrations of (210)Po, (234)U, and (238)U in the two analyzed kinds of mosses: schrebers big red stem moss (Pleurozium schreberi) and broom moss (Dicranum scoparium) were similar. The higher polonium concentrations were found in broom moss (Dicranum scoparium), but uranium concentrations were relatively low for both species of analyzed mosses. Among the analyzed trace metals the highest concentration in mosses was recorded for iron, while the lowest for nickel, cadmium and mercury. The obtained studies showed that the sources of polonium and uranium isotopes, as well as trace metals in analyzed mosses are air city contaminations transported from Gdańsk and from existing in the vicinity the phosphogypsum waste heap in Wiślinka (near Gdańsk).

  10. Investigation of corrosion, water reaction, polonium evaporation and bismuth resource in liquid metal lead-bismuth technology

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Hideki; Takizuka, Takakazu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kitano, Teruaki [Mitsui Shipbuilding and Engineering Co. Ltd., Tokyo (Japan)

    2000-10-01

    Lead-bismuth is the first candidate material for liquid metal target find coolant of fueled blanket system in accelerator-driven system (ADS) studied at JAERI. Advantages of the lead-bismuth utilization are non-active material, very low capture cross section, low melting point of 125degC and high boiling point of 1670degC, and beside coolant void reactivity become negative. But problems are due to the high corrosivity to most of the structural materials and the corrosive data are scarcity. In this report, corrosivity, reaction with water, thermal-hydraulics, chemical toxicity etc. are studied by investigating some facilities utilized and researched really for lead or lead-bismuth. And, furthermore, polonium evaporation rate and bismuth resource are investigated. Main results obtained are as follows: (1) In a refinery, there are enough employment experience for liquid Pb-Bi in period of about 17 years and not corrosion for the thermal conductive materials (1Cr-0.5Mo steel) used under the condition of natural convection with temperature around 400degC. (2) In Russia, extensive experience in the use as Russian submarines and in R and D during about 50 years are available. And as a result, it will be able to lead approximately zero corrosion for Cr-Si materials by adjusting oxygen film with oxygen concentration control between 10{sup -7} to 10{sup -5}% mass. However, the corrosion data are not enough systematically collected involving them in radiation dose field. (3) In liquid-dropping experiment, it is shown that interaction between water and high temperature liquid Pb-Bi is reduced steeply with rising of atmosphere pressure. But, in order to design the second circuit removal model of ADS, the interaction should be evaluated by water continuous injection experiment. (4) Polonium forms PbPo in Pb-Bi, and the evaporation rate become less three factor than that of Po, and furthermore, the rate decreases in the atmosphere. The effects of Po on employee and environment

  11. Polonium 210 and lead 210 in Syrian sea and lake fish and the dose due to their intake

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Mamish, S.; Budeir, Y.; Nashwaty, A.

    1998-09-01

    Edible part of 36 types of sea fish collected from local market (Lattakia, Tartus, Banias) and seven types of river fish (Euphrate river and Mzerib lake) have been analyzed for 210 Po and 210 Pb. Results of analysis have shown that 210 Po and 210 Pb concentrations in sea fish varied between 0.27 and 27.48 Bq/kg and between 0.05 and 0.38 Bq/kg, respectively while for river fish concentrations were relatively low and varied between 0.61 and 3.08 Bq/kg for 210 Po and between 0.04 and 0.10 Bq/kg for 210 Pb. In addition, the Syrian adults daily intakes of 210 Po and 210 Pb have been estimated and found to be 6.0 and 0.24 mBq respectively. These intakes are much less than those reported in other areas in the world. The collective dose was also determined and found to be about 5.09 man.Sv for polonium 210 and 2.93 man.Sv for lead 210 . (author)

  12. The effect of preparation processes on polonium 210 transfer from tea and mate leaves to aqueous extract

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Nashawati, A.; Amin, Y.; Al-Akel, B.

    2002-08-01

    Polonium 210 was determined in 34 kinds of tea samples and 8 kinds of mate samples collected from the local market. The results have shown that the activities of 210 Po in tea and meta samples were relatively high and varied between 5.5 and 39 Bq.Kg -1 , and 47 to 82 Bq.Kg -1 in tea and mate samples respectively. In order to estimate the annual intake of 210 Po by drinking of the aqueous extract of these materials, preparation processes of the leaves were performed at different conditions (temperature, duration of soaking). The results have shown that the amount of 210 Po transferred to the aqueous extract varied between 9 and 21% and 3 and 15% for tea leaves and mate respectively. There was a clear variations in the soluble amount according to the applied different conditions of soaking. The annual intake of 210 Po due to drinking tea and meta extracts was calculated and found to be 9 Bq.year -1 and 151 Bq.year -1 for tea and mate respectively. (author)

  13. Uranium series radionuclides, polonium-210 and lead-210, in the lichen-caribou-wolf food chain of the Northwest Territories

    International Nuclear Information System (INIS)

    Thomas, P.A.; Sheard, J.W.; Swanson, S.

    1994-01-01

    This report examines baseline concentrations and transfer of the uranium decay products polonium-210 and lead-210 in the lichen-caribou-wolf food chain at two locations in the Northwest Territories, Baker Lake and Snowdrift. At each location, concentrations of the two radionuclides were determined in the lichen species Cetraria nivalis and Cladina mitis, and several tissues from caribou and wolves. Baseline concentrations and transfer coefficients within the food chain were compared between the two locations. Lichen samples were also collected from Kasba Lake, a third hunting ground used by northern Saskatchewan hunters. The lichen species chosen were common forage for caribou. Both the predominant lichen species at each location and rumen contents were used to estimate the winter diet of caribou in the calculation of transfer coefficients. The results are relevant to environmental monitoring in areas of potential future uranium mining development and the transfer coefficients determined in the study may be used to estimate radionuclide concentrations and radiation doses in future environmental assessments

  14. Polonium-210 and selenium in tissues and tissue extracts of the mussel Mytilus galloprovincialis (Gulf of Trieste).

    Science.gov (United States)

    Kristan, Urška; Planinšek, Petra; Benedik, Ljudmila; Falnoga, Ingrid; Stibilj, Vekoslava

    2015-01-01

    Marine organisms such as mussels and fish take up polonium (Po) and selenium (Se), and distribute them into different cellular components and compartments. Due to its high radiotoxicity and possible biomagnification across the marine food chain Po-210 is potentially hazardous, while selenium is an essential trace element for humans and animals. The aim of this study was to investigate and compare the presence and extractability of the elements in the mussels Mytilus galloprovincialis collected in the Gulf of Trieste. The levels of Po-210 in the samples ranged from 220 to 400 Bq kg(-1) and of Se from 2.6 to 8.2 mg kg(-1), both on a dry matter basis. Using various extraction types and conditions in water, buffer or enzymatic media, the best extractability was obtained with enzymatic extraction (Protease XIV, 1h shaking at 40 °C) and the worst by water extraction (24 h shaking at 37 °C). 90% of Po-210 and 70% of Se was extractable in the first case versus less than 10% of Po-210 and less than 40% of Se in the second. Such evident differences in extractability between the investigated elements point to different metabolic pathways of the two elements. In enzymatic extracts Se speciation revealed three Se compounds (SeCys2, SeMet, one undefined), while Po-210 levels were too low to allow any conclusions about speciation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. A study on possible use of Urtica dioica (common nettle) plant as polonium (210)Po and lead (210)Pb contamination biomonitor in the area of phosphogypsum stockpile.

    Science.gov (United States)

    Olszewski, Grzegorz; Boryło, Alicja; Skwarzec, Bogdan

    2016-04-01

    The aim of this study was to test a possible use of Urtica dioica (common nettle) plant as a biomonitor of polonium (210)Po and lead (210)Pb contamination near phosphogypsum stacks by determining concentrations of these radionuclides in samples collected from the area of phosphogypsum stockpile in Wiślinka (northern Poland). The (210)Po and (210)Pb contents in roots depended on their concentrations in soils. Bioconcentration factor values from soil to root of the plant did not depend on (210)Po and (210)Pb contents in soils that leads to the conclusion that different polonium and lead species have different affinities to U. dioica plants. The main sources of both analyzed radionuclides in green parts of plants are wet and dry air deposition and transportation from soil. The values of (210)Po/(210)Pb activity ratio indicate natural origin of these radioisotopes in analyzed plants. (210)Po and (210)Pb concentration in U. dioica roots is negatively weakly correlated with distance from phosphogypsum stockpile.

  16. The research for a method for controlling atmospheric pollution in a plutonium treatment cell; Recherche d'une methode de controle de la pollution atmospherique dans une cellule traitant le polonium

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    The aerosols likely to contain {sup 210}Po are trapped by bubbling through an acid solution. The problem of determining the polonium concentration of the solution has been solved by combining it with telluric acid. The reduction is carried out at pH = 0 using a solution of stannous chloride. We have studied the factors influencing coprecipitation; nature of the medium, pH, amounts of telluric acid and of stannous chloride. The average yield for the precipitation is 93 per cent. After precipitation, the polonium is filtered on paper and its activity is measured by means of a scintillation counter. The method makes it possible to measure 1/20 of the maximum permissible dose with an accuracy of 20 per cent. (author) [French] Les aerosols susceptibles de contenir du {sup 210}Po sont captes par barbotage dans une solution acide. Le probleme de la concentration de la solution en polonium a ete resolu en entrainant celui-ci avec de l'acide tellurique. La reduction est effectuee a pH = 0 par une solution de chlorure stanneux. Nous avons etudie les facteurs influencant la coprecipitation: nature du milieu, pH, quantite d'entraineur, quantite de chlorure stanneux. Le rendement moyen de la precipitation est de 93 pour cent. Apres precipitation, le polonium est filtre sur papier et son activite mesuree au compteur a scintillations. La methode permet de mesurer le 1/20 de la dose maximum permise avec une precision de 20 pour cent. (auteur)

  17. Spontaneous-fission decay properties and production cross-sections for the neutron-deficient nobelium isotopes formed in the sup 4 sup 4 sup , sup 4 sup 8 Ca+ sup 2 sup 0 sup 4 sup , sup 2 sup 0 sup 6 sup , sup 2 sup 0 sup 8 Pb reactions

    CERN Document Server

    Belozerov, A V; Chepigin, V I; Drobina, T P; Gorshkov, V A; Kabachenko, A P; Malyshev, O N; Merkin, I M; Oganessian, Yu T; Popeko, A G; Sagaidak, R N; Svirikhin, A I; Yeremin, A V; Berek, G; Brida, I; Sáro, S

    2003-01-01

    Heavy-ion fusion reactions sup 4 sup 8 Ca+ sup 2 sup 0 sup 4 Pb and sup 4 sup 4 Ca+ sup 2 sup 0 sup 8 Pb leading to the same compound nucleus sup 2 sup 5 sup 2 No sup * were run in attempts to produce new neutron-deficient spontaneous-fission isotopes of sup 2 sup 4 sup 9 sup , sup 2 sup 5 sup 0 No using the electrostatic separator VASSILISSA. Production cross-sections for the spontaneous-fission activities with the half-lives 5.6 and 54 mu s observed in these reactions are compared with the measured ones for the well-known isotopes of sup 2 sup 5 sup 1 sup - sup 2 sup 5 sup 5 No formed in the heavy-ion fusion reactions sup 4 sup 8 Ca+ sup 2 sup 0 sup 6 Pb and sup 4 sup 8 Ca+ sup 2 sup 0 sup 8 Pb. The obtained excitation functions for the reaction products formed after the evaporation of 1-4 neutrons from the corresponding compound No nuclei have been compared with similar data obtained earlier and results of statistical model calculations. (orig.)

  18. Study on the bioaccumulation of Polonium-210 on bivalve indicator organisms of Tamilnadu and Pondicherry coast (East Coast of India)

    International Nuclear Information System (INIS)

    Syed Mohamed, H.E.; Sadiq Bukhari, A.; Meeramaideen, M.; Masilamani, V.; Shamsudin, Mohamed; Shahul Hameed, P.

    2012-01-01

    210 Po is a major contributor (90%) of the natural radiation dose from alpha-emitting radionuclides, received by most marine organisms. Among marine organisms, benthic fauna are superior to many other biological groups, since they could be monitored due to their sedentary habits and then must either adapt to environmental stress or perish. They also reflect the water conditions not only at the time of sampling but also for some past time as well. The affinity of 210 Po for protein enables it to pass through the food chain, and increased body burdens of 210 Po have been found where diets include protein-rich meat and seafood. The present study was launched to evaluate the rate of accumulation of 210 Po in the benthic bivalve molluscs such as Perna indica, P.viridis, Meretrix casta, Cardium coronatum, Gafrarium tumidum, Paphia textrix, Vellorita cyprinodea and Pinctada sp., of Tamilnadu and Pondicherry coast. Water samples, sediments and bivalves were collected from Gulf of Mannar (6 sampling stations), Palk Strait (8 sampling stations) of Tamilnadu and Pondicherry (6 sampling stations). 210 Po determination as made was as per standard protocols. The results showed that 210 Po concentration in coastal waters of Gulf of Mannar, Palk Strait and Pondicherry ranged 0.5 - 2.83 mBq/l (mean 1.33 mBq/I), 2.14 - 32.14 mBq/l (mean 15.3 mBq/l) and 1.36 - 2.0 mBq/1 (mean 1.59 mBq/1) respectively. The sediments maintained higher level of 210 Po (mean value of 3.62 Bq/kg in Gulf of Mannar, 107.9 Bq/kg in Palk Strait and 3.0 Bq/kg in Pondicherry) than water. The 210 Po rich sediment therefore serves as a vital link in the transfer of Polonium from water to the marine organisms. The concentration of 210 Po in eight species of bivalves collected from the study area, recorded a maximum level ranging from 65.2 to 2668.9 Bq/kg in soft tissues and from 1.19 to 15.3 Bq/kg in shells. The bioaccumulation ability in bivalve species with reference to 210 Po was observed to be highly variable

  19. Clustering effects in fusion evaporation reactions with light even-even N = Z nuclei. The {sup 24}Mg and {sup 28}Si cases

    Energy Technology Data Exchange (ETDEWEB)

    Morelli, L., E-mail: luca.morelli@bo.infn.it; D’Agostino, M.; Bruno, M. [Dipartimento di Fisica e Astronomia dell’Università and INFN, Bologna (Italy); Baiocco, G. [Dipartimento di Fisica dell’Università and INFN, Pavia (Italy); Gulminelli, F. [CNRS, LPC, Caen, France and ENSICAEN, Caen (France); Cinausero, M.; Gramegna, F.; Marchi, T. [INFN, Laboratori Nazionali di Legnaro, Legnaro (Padova) (Italy); Degerlier, M. [University of Nevsehir, Physics Department, Nevsehir (Turkey); Fabris, D. [INFN, Sezione di Padova, Padova (Italy); Barlini, S.; Bini, M.; Casini, G.; Gelli, N.; Olmi, A.; Pasquali, G.; Piantelli, S. [Dipartimento di Fisica e Astronomia dell’Università and INFN, Firenze (Italy)

    2015-10-15

    In the recent years, cluster structures have been evidenced in many ground and excited states of light nuclei [1, 2]. Within the currently ongoing experimental campaign by the NUCL-EX collaboration we have measured the {sup 12}C+{sup 12}C and {sup 14}N+{sup 10}B reactions at 95 MeV and 80 MeV respectively, and compared experimental data corresponding to complete fusion of target and projectile into an excited {sup 24}Mg nucleus to the results of a pure statistical model[3, 4]. We found clear deviations from the statstical model in the decay pattern: emission channels involving multiple α particles are more probable than expected from a purely statistical behavior. To continue the investigation on light systems, we have recentely measured the {sup 16}O+{sup 12}C reaction at three different beam energies, namely E{sub beam} = 90, 110 and 130 MeV.

  20. Consistent evaluations of (n,2n) and (n,np) reaction excitation functions for some even-even isotopes using empirical systematics

    OpenAIRE

    Manokhin, V. N.; 小田野 直光; 長谷川 明

    2001-01-01

    (n,np)反応断面積のしきいエネルギーが(n,2n)反応断面積のしきいエネルギーよりも低い偶々核について、(n,1p)反応と(n,np)反応の両者の断面積の励起関数を矛盾なく評価するアプローチについて論じた。(n,2n)及び(n,np)反応断面積の励起関数の最大値の決定においては、Manokhinの系統式を用いるとともに、(n,2n)及び(n,np)反応のしきいエネルギーの差の質量依存性も考慮した。(n,2n)及び(n,np)反応の励起関数の計算には、Manokhinの系統式によって与えられる規格化された励起関数を用いた。いくつかの核種に対する(n,2n)及び(n,np)反応断面積の評価を行い、本研究における手法が妥当であることを明らかにした。...

  1. Multiphonon K/sup π/+ states in even-even deformed nuclei. II. Calculation of matrix elements of a general Hamiltonian

    International Nuclear Information System (INIS)

    Silvestre-Brac, B.; Piepenbring, R.

    1978-01-01

    Matrix elements of a general Hamiltonian H in a subspace spanned by collective K/sup π/+ deformed phonons are derived with the help of recursion formulas. Various approximations are discussed both in the fermion space and in the boson space. Careful comparisons are made in the framework of a simple solvable model

  2. Multiphonon states in even-even spherical nuclei. Pt. 2. Calculation of the matrix elements of one and two body operators

    International Nuclear Information System (INIS)

    Piepenbring, R.; Protasov, K.V.; Silvestre-Brac, B.

    1995-01-01

    Matrix elements of one and two body operators, which appear in a general hamiltonian and in electromagnetic transitions are derived in a subspace spanned by multiphonon states. The method is illustrated for a single j-shell, where phonons built with one type of particles are introduced. The eigenvalues obtained within the space spanned by the phonons of lowest angular momentum are compared to those of the full space. In such a method, the Pauli principle is fully and properly taken into account. ((orig.))

  3. Clustering effects in fusion evaporation reactions with light even-even N=Z nuclei. The 24Mg and 28Si cases

    Directory of Open Access Journals (Sweden)

    Morelli L.

    2016-01-01

    Inclusive variables are in general well reproduced by the model. We found clear deviations from the statistical model if we select emission channels involving multiple α particles which are more probable than expected from a purely statistical behavior. Data from 12C+12C reaction have been analyzed in order to study the decay of the Hoyle state of 12C* with two different selections: peripheral binary collisions and 6α decay channel in central events. To continue the investigation on light systems, we have recently measured the 16O+12C reaction at three different beam energies, namely Ebeam = 90, 110 and 130 MeV. Preliminary results are presented.

  4. A special type of neutron-proton pairing interaction and the moments of inertia of some deformed even-even nuclei in the rare earth region

    International Nuclear Information System (INIS)

    Meftunoglu, E.; Gerceklioglu, M.; Erbil, H.H.; Kuliev, A.A.

    1998-01-01

    In this work, the effect of a special type of neutron-proton pairing interaction on the moments of inertia of some deformed nuclei in the rare earth region is investigated. First, making a perturbative approximation, we assume that the form of the equations of the BCS theory and usual Bogolyubov transformations are unchanged. Second, we use a phenomenological method for the strength of this neutron-proton pairing interaction introducing a parameter. Calculations show that this interaction is important for the ground-state moments of inertia and that it could be effectual in other nuclear phenomena. (author)

  5. Systematics of triaxial moment of inertia and deformation parameters (β, γ) in even-even nuclei of mass region A = 90-120

    International Nuclear Information System (INIS)

    Singh, Yuvraj; Gupta, D.K.; Singh, M.; Gupta, K.K.; Bihari, Chhail; Varshney, A.K.; Dhiman, S.K.

    2012-01-01

    The deformation parameter β and γ of the collective model of Bohr and Mottelson are basic descriptors of the nuclear equilibrium shape and structure. In recent past the sets of deformation parameters ((β, γ) have been extracted from both level energies and E2 transition rates in even Xe, Ba and Ce nuclei (A∼120-140) and Hf, W, Os, Pt and Hg nuclei (A∼160-200) using rigid triaxial rotor model of Davydov-Filippov (DF). Researcher have found that the values of β obtained separately from energy and transition rate (β e and β b respectively), though, are found almost equal in heavy mass region (A ∼160-200) but, not so in medium mass (A∼120-140) nuclei. This observation puts a question mark whether the ββ dependence of moment of inertia in hydrodynamic model is reliable. The purpose of the present work is to study a relatively lighter mass region (A∼90-120) where the gap between values of two sets of β may further increase. To improve the calculations for extracting β e , the use of Grodzins rule will be made along with uncertainties, since only through this rule the E2 1 + is related with β G (value of β for symmetric nucleus and evaluated using Grodzins rule)

  6. Histochemical, light and electron microscopic study of polonium-210 induced peripheral tumours in hamster lungs -evidence implicating the Clara Cell as the cell of origin

    International Nuclear Information System (INIS)

    Kennedy, A.R.; McGandy, R.B.; Little, J.B.

    1977-01-01

    Peripheral lung tumors induced in Syrian golden hamsters by intratracheally administered polonium-210 ( 210 Po) are similar to the peripheral lung tumours induced in many species by a variety of carcinogens. In addition, they show many of the histopathological features observed in human bronchiolar-alveolar carcinomas. Serial sacrifice studies of hamsters exposed to multiple instillations of 210 Po have been carried our to identify the cell of origin of these tumors. By means of thin, plastic (glycol methacrylate) sections, electron microscopy, and histochemistry, it is concluded that the bronchiolar Clara cell is the probable cell of origin, and that this view is generally compatible with many of the reported cytological characteristics of the human tumor. (author)

  7. The significance of lead-210, polonium-210 and protactinium-231 in emissions from coal-fired power stations: a comparison with natural environmental sources

    International Nuclear Information System (INIS)

    Corbett, J.O.

    1981-04-01

    Recently published calculations have suggested that a hypothetical individual may receive an effective radiation dose equivalent of 23 mrem/y from coal-fired power station emissions through the ingestion of lead-210, polonium-210 and protactinium-231. It is shown that the model used in those calculations is over-pessimistic by one or two orders of magnitude when applied to the deposition of Pb-210 and Po-210 derived from the decay of radon naturally present in the atmosphere. A more recent assessment of metabolic data for Pa-231 suggests that estimated doses from this nuclide also can be reduced by about a factor of twenty. It is concluded that the maximum effective dose equivalent from power station emissions probably does not exceed 1-2 mrem/y. (author)

  8. Polonium-210 in tobacco

    International Nuclear Information System (INIS)

    Harley, N.H.; Cohen, B.S.; Tso, T.C.

    1978-01-01

    The purpose of this paper was to present the measurements that have been made on tobacco and tobacco products and to indicate the studies that show the amount of 210 Po transferred to mainstream smoke and inhaled. The amounts reported to be in the lung are summarized. The authors have shown what average values might be expected in the lung due to normal deposition and clearance of the smoke aerosol and to compare these values with the measurements. The average dose to cells in the bronchial epithelium was estimated for the activities reported to be on the bronchial surface, and a comparison of this dose with a known tumorigenic alpha dose was made

  9. Method for evaluation of doses from ingestion of polonium, bismuth and lead as natural radioactive material(NORM); Metodo de evaluacion de dosis por ingestion de polonio, bismuto y plomo como materiales radiactivos naturales

    Energy Technology Data Exchange (ETDEWEB)

    Pena, Vanessa; Puerta, Anselmo; Morales, Javier, E-mail: vpenam@ullal.edu.co, E-mail: japuerta@unal.edu.co, E-mail: jmorales@unal.cdu.co [Universidad Nacional de Colombia, Medellin (Colombia). Grupo de Fisica Radiologica

    2013-07-01

    In this work was carried out an evaluation of dose from ingestion of radioactive daughters of radon (lead, bismuth and polonium), taking into account ages from three months up to adult men, using the new model of the human alimentary tract HATM and methodology of calculating doses proposed by the ICRP publication 103, which allows the estimation of dose based on the concentration of the radionuclide present in the diet or in the water of consumption.

  10. Study of the neutron deficient nucleus {sup 180}Pt

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Gatermann, Claus; Fransen, Christoph; Dewald, Alfred; Braunroth, Thomas; Litzinger, Julia; Jolie, Jan; Zell, Karl-Oskar [Institut fuer Kernphysik, Universitaet zu Koeln (Germany); Julin, Rauno; Grahn, Tuomas [Dept. of Physics, University of Jyvaeskylae (Finland); Petkov, Pavel [Bulgarian Academy of Sciences, Sofia (Bulgaria)

    2016-07-01

    The nuclei {sup 176,178,180}Os are known to show the characteristic features of the critical point symmetry X(5). This symmetry was introduced by F. Iachello and describes nuclei at the critical point of deformation phase transition from a vibrator to axial rotor. A rapid change in deformation is expected when the proton number is changed, because the neutron number is close to mid-shell. Therefore we performed measurements to determine the lifetimes of low lying states in {sup 180}Pt which is a neighbor of the X(5) type Os nuclei, from which absolute transition probabilities can be deduced directly. In this contribution we will report on a Recoil distance Doppler shift experiment which was performed at the JYFL, Jyvaeskylae (Finland). Furthermore the results of the {sup 168}Yb({sup 16}O,4n){sup 180}Pt experiment using the fast timing technique to determine the lifetime of the rather longlived first 2{sup +} state at the IKP, University of Cologne (Germany) are presented. The experimental results will be discussed in the framework of the Interacting Boson Model and compared to a General Collective Model calculation.

  11. Studies of neutron-deficient mendelevium isotopes at SHIP

    Energy Technology Data Exchange (ETDEWEB)

    Antalic, S.; Saro, S. [Comenius University, Department of Nuclear Physics and Biophysics, Bratislava (Slovakia); Hessberger, F.P.; Ackermann, D.; Heinz, S.; Kindler, B.; Kojouharov, I.; Lommel, B.; Mann, R. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt am Main (Germany); Kuusiniemi, P. [University of Oulu, Centre for Underground Physics in Pyhaesalmi (CUPP), Oulu (Finland); Leino, M. [University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland)

    2010-01-15

    The radioactive decay of the isotopes {sup 247}Md, {sup 246}Md and their daughter products was investigated by means of {alpha}-{alpha} and {alpha}-{gamma} coincidence spectroscopy. The isotopes were produced using the fusion reaction {sup 40}Ar + {sup 209}Bi. Decay schemes are suggested for {sup 247}Md and {sup 243}Es. A new isomeric state in {sup 246}Md with a half-life of (4.4{+-}0.8) s was observed. Previous data of electron-capture delayed fission of {sup 246}Md and {sup 242}Es were confirmed. The probability for this decay branch in {sup 246}Md was measured to be P{sub ECDF}>0.10. The probability for electron-capture delayed fission in the case of {sup 242}Es was determined to be P{sub ECDF}=0.013{sup +0.012} {sub -0.007}. (orig.)

  12. Projected shell model study of neutron- deficient 122Ce

    Indian Academy of Sciences (India)

    Projected shell model; band diagram; yrast energies; electromagnetic quan- ... signed to 122Ce by detecting γ-rays in coincidence with evaporated charged particles .... 0.75 from the free nucleon values to account for the core-polarization and ...

  13. Nuclear radiation detected optical pumping of neutron deficient Hg isotopes

    International Nuclear Information System (INIS)

    Bonn, J.

    1975-01-01

    The extension of the Nuclear Radiation Detected Optical Pumping method to mass-separated samples of isotopes far off stability is presented for a series of light Hg isotopes produced at the ISOLDE facility at CERN. The isotope under investigation is transferred by an automatic transfer system into the optical pumping apparatus. Zeeman scanning of an isotopically pure Hg spectral lamp is used to reach energetic coincidence with the hyperfine structure components of the 6s 2 1 S 0 -6s6p 3 P 1 (lambda = 2537 A) resonance line of the investigated isotope and the Hg lamp. The orientation build up by optical pumping is monitored via the asymmetry or anisotropy of the nuclear radiation. Nuclear spins, magnetic moments, electric quadrupole moments and isotopic shift are obtained for 181 Hg- 191 Hg using the β-asymmetry as detector. The extension of the method using the γ-anisotropy is discussed and measurements on 193 Hg are presented. (orig./HK)

  14. Accurate mass measurements on neutron-deficient krypton isotopes

    CERN Document Server

    Rodríguez, D.; Äystö, J.; Beck, D.; Blaum, K.; Bollen, G.; Herfurth, F.; Jokinen, A.; Kellerbauer, A.; Kluge, H.-J.; Kolhinen, V.S.; Oinonen, M.; Sauvan, E.; Schwarz, S.

    2006-01-01

    The masses of $^{72–78,80,82,86}$Kr were measured directly with the ISOLTRAP Penning trap mass spectrometer at ISOLDE/CERN. For all these nuclides, the measurements yielded mass uncertainties below 10 keV. The ISOLTRAP mass values for $^{72–75}$Kr being more precise than the previous results obtained by means of other techniques, and thus completely determine the new values in the Atomic-Mass Evaluation. Besides the interest of these masses for nuclear astrophysics, nuclear structure studies, and Standard Model tests, these results constitute a valuable and accurate input to improve mass models. In this paper, we present the mass measurements and discuss the mass evaluation for these Kr isotopes.

  15. Simultaneous Two-Proton Emission Process of Neutron Deficient Nuclei

    International Nuclear Information System (INIS)

    Rodrigues, M. M. N.; Duarte, S. B.; Leite, T. N.; Teruya, N.

    2011-01-01

    In a previous work, we have calculated the one-proton emission rate of nuclei near the proton drip line, by using an analytical barrier parametrization. The calculation is based on the WKB-approximation and half-lives are obtained in good agreement with the existing experimental data for one-proton emitters. Motivated by these results, in present work, we have eliminated the artificial barrier parametrization previously used, constructing a realistic barrier composed by the superposition of a nuclear Wood-Saxon potential form plus the coulomb and centrifugal barrier. The purpose here is to see if the simple WKB-calculation is still able to reproduce recent observed experimental results for two-proton emission from 45 Fe. This decay mode has been observed by Miernik et al., reporting the proton energy distribution and half-life energy dependence for 45 Fe simultaneous 2p-emission. For theoretical determination of the half-life and these energy distributions we evoked a statistical assumption of a pioneering Goldansky's work for discussing simultaneous two-proton emission. We have shown that our calculation reproduce in quite good agreement the energy distribution and is also able to offer good half-life result with an appropriated composition of involved values of the angular momentum decay.

  16. Decay studies of neutron-deficient lawrencium isotopes

    International Nuclear Information System (INIS)

    Antalic, S.; Saro, S.; Streicher, B.; Venhart, M.; Hessberger, F.P.; Ackermann, D.; Heinz, S.; Kindler, B.; Kojouharov, I.; Lommel, B.; Mann, R.; Hofmann, S.; Kuusiniemi, P.; Leino, M.; Nishio, K.; Sulignano, B.

    2008-01-01

    The radioactive decay of the isotopes 254-256 Lr and their daughter products was investigated by means of α, prompt α-γ and delayed conversion electron-γ coincidence spectroscopy. The isotopes were produced using the reaction 48 Ca+ 209 Bi. (orig.)

  17. Decay studies of the highly neutron-deficient indium isotopes

    International Nuclear Information System (INIS)

    Wouters, J.M.

    1982-02-01

    An extension of the experimentally known nuclidic mass surface to nuclei far from the region of beta-stability is of fundamental interest in providing a better determination of the input parameters for the various nuclear mass formulae, allowing a more accurate prediction of the ultimate limits of nuclear stability. In addition, a study of the shape of the mass surface in the vicinity of the doubly-closed nuclide 100 Sn provides initial information on the behavior of the shell closure to be expected when Z = N = 50. Experiments measuring the decay energies of 103 105 In by β-endpoint measurements are described with special attention focused on the development of a plastic scintillator β-telescope coupled to the on-line mass separator RAMA (Recoil Atom Mass Analyzer). An attempt to measure the β-endpoint energy of 102 In is also briefly described. The experimentally determined decay energies and derived masses for 103 105 In are compared with the predictions of different mass models to identify which models are more successful in this region. Furthermore, the inclusion in these comparisons of the available data on the neutron-rich indium nuclei permits a systematic study of their ground state mass behavior as a function of the neutron number between the shell closures at N = 50 and N = 82. These analyses indicate that the binding energy of 103 In is 1 MeV larger than predicted by the majority of the mass models. An examination of the Q/sub EC/ surface and the single- and two-neutron separation energies in the vicinity of 103 105 In is also performed to investigate further the deviation and other possible systematic variations in the mass surface in a model-independent way

  18. Investigation of environmental conditions at Sarfartoq 1987-88. Collection of samples for testing, measurement of radon and analyses for polonium-210 and lead-210. [Greenland]. Miljoeundersoegelser ved Sarfartoq 1987-88. Proeveindsamling, radonmaaling og analyser for polonium-210 og bly-210

    Energy Technology Data Exchange (ETDEWEB)

    Aastrup, P; Munk Hansen, M

    1989-01-01

    The sampling of plants and animals is part of environmental base line studies initiated by the Mineral Resources Administration for Greenland in relation to plans for exploration and exploitation of a niobium occurence. Samples have been collected in areas expected to be influenced by mining activities and in reference areas. The collected species of plants include northern willow, Bellard's kobresia, lichen (Cetraria nivalis), and others. Samples of animals include musk oxen, reindeer, alpine hare, ptarmigan, fox, and arctic char. However, 60 samples have been analyzed for polonium-210 and lead-210. The highest concentrations were found in lichen and the lowest in muscle tissue. In many samples systematic differences between the concentrations of the two isotopes were observed indicating that polonium-210 should continue to be part of the base line study program and the monitoring program if mining is started. The observed concentrations pose no health problem. 30 kg bulk samples of the best pyrochlore ore and the rock c. 10 m on both sides of the mineralization (the side rock) were analyzed for niobium, tantalum, some trace elements, and natural radioactive isotopes. The ore sample has concentrations of 33.17% niobium, 0.4% tantalum, 0.77% uranium, and more than 0.37% rare earth elements. The concentrations of all other analyzed elements are low. The ore has very well defined boundaries and there is a very low concentration of radioactive elements in the side rock. The naturally occurring concentrations of radon have been measured at stations on top of the mineralization, within the carbonatite complex and outside the complex. The concentrations generally are very low. However, the concentrations in the complex are significantly higher than outside the complex. This reflects an elevated uranium concentration of the carbonatite complex rocks. (AB).

  19. Polonium 2 sup 1 sup 0 and lead 2 sup 1 sup 0 in Syrian sea and river fish and radiation dose due to their consumption

    International Nuclear Information System (INIS)

    Al-Masri, M.S.; Mamish, S.; Budier, Y.; Nashwati, A.

    1999-01-01

    Edible part of 36 types of sea fish collected from local market (Lattakia, Tartus, Banias) and seven types of river fish (Al-Furat river and Mzerib lake) have been analyzed for 210 Po and 210 Pb. Results of analysis have shown that 210 Po and 210 Pb concentrations in sea fish varied between 0.27 and 27.48 Bq/kg and between 0.05 and 0.38 Bq/kg, respectively while for river fish concentrations were relatively low and varied between 0.61 and 3.08 Bq/kg for 210 Po and between 0.04 and 0.10 Bq/kg for 210 Pb. In addition, the Syrian adults daily intakes of 210 Po and 210 Pb have been estimated and found to be 6.0 and 0.24 mBq respectively. These intakes are much less than those reported in other areas in the world. The collective dose was also determined and found to be about 5.09 man.sv for polonium 210 and 2.93 man.sv for lead 210 . (author)

  20. Methods and Data Used to Investigate Polonium-210 as a Source of Excess Gross-Alpha Radioactivity in Ground Water, Churchill County, Nevada

    Science.gov (United States)

    Seiler, Ralph L.

    2007-01-01

    Ground water is the major source of drinking water in the Carson River Basin, California and Nevada. Previous studies have shown that uranium and gross-alpha radioactivities in ground water can be greater than U.S. Environmental Protection Agency Maximum Contaminant Levels, particularly in the Carson Desert, Churchill County, Nevada. Studies also have shown that the primary source of the gross-alpha radioactivity and alpha-emitting radionuclides in ground water is the dissolution of uranium-rich granitic rocks and basin-fill sediments that have their origins in the Sierra Nevada. However, ground water sampled from some wells in the Carson Desert had gross-alpha radioactivities greater than could be accounted for by the decay of dissolved uranium. The occurrence of polonium-210 (Po-210) was hypothesized to explain the higher than expected gross-alpha radioactivities. This report documents and describes the study design, field and analytical methods, and data used to determine whether Po-210 is the source of excess gross-alpha radioactivity in ground water underlying the Carson Desert in and around Fallon, Nevada. Specifically, this report presents: 1) gross alpha and uranium radioactivities for 100 wells sampled from June to September 2001; and 2) pH, dissolved oxygen, specific conductance, and Po-210 radioactivity for 25 wells sampled in April and June 2007. Results of quality-control samples for the 2007 dataset are also presented.

  1. Assessment of the hazard to the public from anti-static brushes containing polonium-210 in the form of ceramic microspheres

    International Nuclear Information System (INIS)

    Webb, G.A.M.; Wilkins, B.T.; Wrixon, A.D.

    1975-04-01

    Anti-static brushes containing polonium-210 in the form of ceramic microspheres have been tested and evaluated with regard to their availability to the general public. After summarising existing test information, results are given of routine leakage tests and special tests intended to simulate severe but credible abuse and accidents with these devices. It is found that the low levels of removable contamination and the possible loss of complete microspheres, although in principle undesirable, do not present a significant hazard. The containment integrity of ceramic microspheres under severe conditions (impact and fire) has been found unsatisfactory and it is considered possible that ICRP dose limits could be approached or even exceeded under these severe but credible abuse, accident or disposal conditions. The results of comparative tests with nonradioactive methods for static elimination did not demonstrate any adequate justification for the use of a radioactive material. The potential exposure from Staticmaster Brushes is therefore considered an unnecessary hazard to members of the public. (author)

  2. Radioactive contamination in human by polonium-210 in food from marine origin; Contaminacao radioativa humana por Polonio-210 contido em alimento de origem marinha

    Energy Technology Data Exchange (ETDEWEB)

    Kelecom, Alphonse; Gouvea, Rita de Cassia S.; Kelecom, Philippe Marcel [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Biologia Geral. Lab. de Radiobiologia e Radiometria (LARARA)]. E-mail: egbakel@vm.uff.br

    2005-07-01

    Food from marine origin is considered as one of the sources that most contributes to internal radioactive contamination in humans by polonium-210 ({sup 210}Po). This work intended to check whether a single ingestion of the mussel Perna perna should result in a detectable increase of radioactive contamination in the consumer. The mussel was bought at a fish market localized in the city of Niteroi, RJ, Brazil. It was cooked as usually, and its content in {sup 210}Po determined after acid mineralization, spontaneous electrodeposition on stainless steel disks and alpha counting. Non-smoking volunteers maintained for two weeks a normal diet, but completely avoiding fish and seafood. Then, they ate 200 g of cooked mussel, and collected total faeces and urine every day during ten days. {sup 210}Po level in faeces samples showed a 900% increase at the first day after ingestion, and reached normal levels after 3-4 days. In urine samples, the increase of {sup 210}Po was much lower (50%) and reached a maximum at the fifth day. Such data showed a short time permanence of {sup 210}Po in the intestine. Most of ingested {sup 210}Po ({approx}91%) was eliminated in up to 5 days through faeces. A small amount was absorbed ({approx}5-10%), part of it being eliminated in urine, and the remaining contaminated the human body. (author)

  3. Polonium-210 activity concentration, transfer and dose to certain invertebrates found in the vicinity of the Kudankulam Nuclear Power Project, Tamil Nadu, India

    International Nuclear Information System (INIS)

    Benjamin, J.; Wesley, S.G.; Rajan, M.P.

    2013-01-01

    Invertebrates are significant reference organisms, and some of them tend to accumulate certain radionuclides in increased levels. It is imperative that the levels of radionuclides are measured in certain organism in the vicinity of any major nuclear power project before its commissioning; hence, this study was carried out in the surroundings of the Kudankulam Nuclear Power Project site. The natural radionuclide polonium-210 having affinity to the organic matter in the soil and to the protein content of the animals, is very significant as it delivers a high internal dose to the organisms. The activity concentration of this radionuclide, its transfer and dose were assessed in two terrestrial (earthworm, Pheretima posthuma and land snail, Trachea vittata) and two aquatic (apple snail, Pila globosa and bivalve mollusc, Lamellidens marginalis) invertebrates. The activity concentration of 210 Po was found to be the highest in the earthworm and the lowest in the land snail. The per-animal dose due to 210 Po was the highest for the apple snail and the lowest for the earthworm. The results indicate that 210 Po does not constitute a significant radiological threat to the organisms. (author)

  4. Levels of polonium-210 in highly consumed sea foods from a fish market of the city of Niteroi, RJ-Brazil

    International Nuclear Information System (INIS)

    Marsico, Eliane T.; Sao Clemente, Sergio C. de; Kelecom, Alphonse; Gouvea, Rita de Cassia S.

    2007-01-01

    Polonium-210 ( 210 Po), a short-lived member from the uranium series, is broadly distributed in Nature being among all alpha-emitters the major contributor to the internal dose in man. Studies of diets have shown that marine foods are important sources of this radionuclide. The levels of 210 Po have been determined in three highly consumed marine species, the fishes Sardinella brasiliensis (sardine) and Thunnus atlanticus (tuna), and the shrimp Litopenaeus brasiliensis, purchased from the Niteroi (RJ, Brazil) fish market, and caught along the coast of the state of Rio de Janeiro. Doses of 210 Po were determined for the entire organisms and for some tissues and organs, such as eyes, heart, gills, muscle, stomach liver, intestine and pyloric caecal (fishes) or eyes, head content, exoskeleton, muscle, hepatopancreas and pleopods. 210 Po is not uniformly distributed within these species, the highest levels being observed for sardine in the intestine (1634.6 mBq g-1), tuna in pyloric caecal (4656.1 mBq g-1) and shrimp in the hepatopancreas (1460.5 mBq g-1). The 210 Po activities in sardine, tuna and shrimp, calculated on a mean whole-organism basis, were 64.6, 34.5 and 39.5 Bq kg-1 (dry weight) respectively, with corresponding concentration factors of 7.2 x104, 3.8 x104 and 4.4 x104. Considering body distribution, almost 60% of the total activity is concentrated in the pyloric caecal of both fishes and in the hepatopancreas of the shrimp. In turn, the edible parts concentrate much less activity. (author)

  5. Levels of polonium-210 in highly consumed sea foods from a fish market of the city of Niteroi, RJ-Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Marsico, Eliane T.; Sao Clemente, Sergio C. de [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Faculdade de Veterinaria. Dept. de Tecnologia de Alimentos; Kelecom, Alphonse; Gouvea, Rita de Cassia S. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Biologia Geral. Lab. de Radiobiologia e Radiometria Pedro Lopes dos Santos - LARARA

    2007-07-01

    Polonium-210 ({sup 210}Po), a short-lived member from the uranium series, is broadly distributed in Nature being among all alpha-emitters the major contributor to the internal dose in man. Studies of diets have shown that marine foods are important sources of this radionuclide. The levels of {sup 210}Po have been determined in three highly consumed marine species, the fishes Sardinella brasiliensis (sardine) and Thunnus atlanticus (tuna), and the shrimp Litopenaeus brasiliensis, purchased from the Niteroi (RJ, Brazil) fish market, and caught along the coast of the state of Rio de Janeiro. Doses of {sup 210}Po were determined for the entire organisms and for some tissues and organs, such as eyes, heart, gills, muscle, stomach liver, intestine and pyloric caecal (fishes) or eyes, head content, exoskeleton, muscle, hepatopancreas and pleopods. {sup 210}Po is not uniformly distributed within these species, the highest levels being observed for sardine in the intestine (1634.6 mBq g-1), tuna in pyloric caecal (4656.1 mBq g-1) and shrimp in the hepatopancreas (1460.5 mBq g-1). The {sup 210}Po activities in sardine, tuna and shrimp, calculated on a mean whole-organism basis, were 64.6, 34.5 and 39.5 Bq kg-1 (dry weight) respectively, with corresponding concentration factors of 7.2 x104, 3.8 x104 and 4.4 x104. Considering body distribution, almost 60% of the total activity is concentrated in the pyloric caecal of both fishes and in the hepatopancreas of the shrimp. In turn, the edible parts concentrate much less activity. (author)

  6. Determination of uranium and thorium isotopes and polonium in sediment profiles from Baixada Santista, SP; Determinacao de isotopos de uranio e torio e polonio em perfis de sedimento da Baixada Santista, SP

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Guilherme da Franca

    2010-07-01

    The objective of the present work is to determine the activity concentration of uranium and thorium isotopes and polonium in estuarine sediments from Baixada Santista. The area comprehends nine cities in the Brazilian coast (Bertioga, Guaruja, Santos, Sao Vicente, Cubatao, Praia Grande, Mongagua, Itanhaem and Peruibe). It is one of the most important industrial areas in Brazil due to the large number of industries operating in Cubatao, such as steel, petrochemical and fertilizer industries. That, together with a large population, causes a negative impact on the marine biota. In the present work 10 profiles of sediment cores, with depth varying from 41 to 98 cm, were analyzed. The cores were obtained from Santos, Cubatao, Sao Vicente and Bertioga. The cores were sliced every 2 cm and were treated with both physical and chemical processes, including drying, grinding and sieving. The samples were dissolved by acid digestion, till total dissolution and destruction of organic matter. After the acid digestion, the samples were filtered and evaporated till dryness. The radiochemical techniques used to separate the radionuclides and to prepare the final source for alpha counting were ion exchange chromatography and spontaneous deposition for polonium and electrodeposition for U and Th. The final sources were counted in a surface barrier alpha spectrometer. Values obtained for the radionuclides analyzed were similar to the activity concentrations of sediments in non polluted areas, with the exception of a few samples that showed anthropic influence. (author)

  7. A statistical approach to investigating enhancement of polonium-210 in the Eastern Irish Sea arising from discharges from a former phosphate processing plant.

    Science.gov (United States)

    Dewar, Alastair; Camplin, William; Barry, Jon; Kennedy, Paul

    2014-12-01

    Since the cessation of phosphoric acid production (in 1992) and subsequent closure and decommissioning (2004) of the Rhodia Consumer Specialties Limited plant in Whitehaven, the concentration levels of polonium-210 ((210)Po) in local marine materials have declined towards a level more typical of natural background. However, enhanced concentrations of (210)Po and lead-210 ((210)Pb), due to this historic industrial activity (plant discharges and ingrowth of (210)Po from (210)Pb), have been observed in fish and shellfish samples collected from this area over the last 20 years. The results of this monitoring, and assessments of the dose from these radionuclides, to high-rate aquatic food consumers are published annually in the Radioactivity in Food and the Environment (RIFE) report series. The RIFE assessment uses a simple approach to determine whether and by how much activity is enhanced above the normal background. As a potential tool to improve the assessment of enhanced concentrations of (210)Po in routine dose assessments, a formal statistical test, where the null hypothesis is that the Whitehaven area is contaminated with (210)Po, was applied to sample data. This statistical, modified "green", test has been used in assessments of chemicals by the OSPAR commission. It involves comparison of the reported environmental concentrations of (210)Po in a given aquatic species against its corresponding Background Assessment Concentration (BAC), which is based upon environmental samples collected from regions assumed to be not enhanced by industrial sources of (210)Po, over the period for which regular monitoring data are available (1990-2010). Unlike RIFE, these BAC values take account of the variability of the natural background level. As an example, for 2010 data, crab, lobster, mussels and winkles passed the modified "green" test (i.e. the null hypothesis is rejected) and as such are deemed not to be enhanced. Since the cessation of phosphoric acid production in 1992

  8. Polonium-210 and lead-210 in the Southern Polar Ocean: Naturally occurring tracers of biological and hydrographical processes in the surface waters of the Antarctic Circumpolar Current and the Weddell Sea; Polonium-210 und Blei-210 im Suedpolarmeer: Natuerliche Tracer fuer biologische und hydrographische Prozesse im Oberflaechenwasser des Antarktischen Zirkumpolarstroms und des Weddellmeeres

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, J.

    1997-11-01

    In this thesis the distribution of {sup 210}Po and {sup 210}Pb in the upper 600 m of the Antarctic Circumpolar Current and the Weddell Sea was investigated along north-south transects in austral spring and autumn. {sup 210}Po and {sup 210}Pb can serve as sensitive tracers for the special hydrographic conditions of the Antarctic Circumpolar Current and the Weddell Sea as well as for biological processes during phytoplankton blooms. The {sup 210}Po/{sup 210}Pb disequilibrium was used as a tracer for particle export. This tracer integrates export on a timescale of 276 days because of the 138 day half-life of {sup 210}Po and complements the {sup 234}Th/{sup 238}U disequilibrium as another tracer for plankton production and export on a shorter timescale of several weeks. (orig.) [Deutsch] In der vorliegenden Arbeit wurde die Verteilung von Blei-210 und seinem Enkelnuklid Polonium-210 im Antarktischen Zirkumpolarstrom und im Weddellmeer bis 600 m Tiefe in mehreren meridionalen Transekten im australen Fruehjahr und Herbst waehrend der `Polarstern`-Expeditionen ANT-X/6 und ANT-XI/4 untersucht. Die Verteilung von {sup 210}Pb und {sup 210}Po wird von mehreren Faktoren beeinflusst, sowohl durch die Advektion von Wassermassen im Antarktischen Zirkumpolarstrom und im Weddellmeer als auch von biologischen Prozessen z.B. innerhalb einer Planktonbluete. Bevor die Verteilungsmuster von {sup 210}Pb und {sup 210}Po jedoch als Tracer fuer einen Prozess genutzt werden koennen, muss der Effekt der einzelnen Faktoren auf die Verteilung betrachtet werden. (orig.)

  9. Polonium-210 in Bombay diet

    International Nuclear Information System (INIS)

    Khandekar, R.N.

    1977-01-01

    The results of the measurement of concentration levels of 210 Po in most of the common foods in the typical Bombay diet are given and estimates provided of the total daily intake of 210 Po by an individual of Bombay city. (U.K.)

  10. Polonium-210 in Bombay diet

    Energy Technology Data Exchange (ETDEWEB)

    Khandekar, R N [Bhabha Atomic Research Centre, Bombay (India). Air Monitoring Section

    1977-08-01

    The results of the measurement of concentration levels of /sup 210/Po in most of the common foods in the typical Bombay diet are given and estimates provided of the total daily intake of /sup 210/Po by an individual of Bombay city.

  11. Study of polonium and lead in shellfish (Mytilus Edulis) from NORM discharge area of Aberdeen Bay and Ythan Estuary of Scotland and radiological impact to the local people and environment

    International Nuclear Information System (INIS)

    Satyajit Ghose; Brian Heaton

    2005-01-01

    Introduction The problem of NORM in the oil and gas industry is a result of deposits of radioactive (Ra,BaSO 4 ) scale within pipelines and processing equipment. The build-up of the scale has a significant impact on the activities of the operating company involved and is therefore a costly problem. The pipes and other equipment must therefore be cleaned on a regular basis or disposed of and replaced. Once the LSA scale has been removed from oil processing equipment the main route of disposal is into the sea. This scale contains mainly radium, lead and its daughter products, which have a long half-lives and high radiotoxicity. The volume of NORM waste produced by the petroleum industry is quite impressive. There are 230 oil and gas producing platforms in UK waters together with around 40 onshore oil and gas producing wells. All are involved in NORM production and discharging the NORM contaminated waste to the North Sea. Discharge of radioactive scale waste from offshore platforms into the surface waters of sea has been a matter of concern due to possible environmental effects of radioelements contained in such waters. Subject to certain conditions this is allowed under the UK Radioactive Substances Act 1993 which controls the release of radioactive materials into the environment. In the case for North sea oil and gas field waste, waste from the cleaning of contaminated plant and equipment is either discharged to sea off shore, discharged to sea from a pipeline in Aberdeen or stored at the Dounraey nuclear facility. Although allowed since 1981 no one has ascertained if these conditions are ensuring full protection of fish consumers. Furthermore, the disposal of large amounts of contaminated wastes resulting from the various stages of oil processing can pose an environmental problem due to its content of long lived radionuclides ( 226 Ra t 1/2 = 1600 y and 210 Pb t 1/2 = 22 years). In order that an accurate estimate of the contribution of polonium from NORM discharges

  12. E0 and E2 decay of low-lying 0+ states in the even-even nuclei 206Pb, 208Po, 112-120 Sn and 112114Cd

    International Nuclear Information System (INIS)

    Julin, Rauno.

    1979-04-01

    Several new methods of in-beam conversion-electron and γ-ray spectrometry, applicable in the determination of E0 and E2 decay properties of low-lying 0 + states in even-mass nuclei, have been developed. The main attention has been paid to direct lifetime-measurement and coincidence methods based on the use of the natural pulsing of a cyclotron beam. With the aid of these methods, the similarity of the absolute decay rates of the two-neutron-hole 0 + 2 states in the N = 124 nuclei 206 Pb and 208 Po has been shown. A systematic investigation of the de-excitation of the 0 + 2 and 0 + 3 states in 112 , 11 4 , 116 , 118 , 120 Sn has been carried out. Twelve E0 transitions connecting the 0 + states have been observed, including very strong low-energy E0 transitions between the excited 0 + states, and several absolute transition probabilities have been determined. Furthermore, the new techniques have been applied successfully in determining the absolute E0 and E2 transition rates from the 0 + 2 and 0 + 3 states in 112 Cd and 114 Cd. The use of isotope-shift data in the calculation of the monopole strengths in 206 Pb and 208 Po is discussed. The results on even Sn and Cd nuclei are discussed within the framework of the coexistence of different shapes and of configuration mixing. (author)

  13. Spatial distribution of radionuclides in soil around a coal-fired power plant: lead 210, polonium 210, radium 226, thorium 232, kalium 40 emitted with the fly ash and cesium 137 from the worldwide weapon testing fallout

    Energy Technology Data Exchange (ETDEWEB)

    Bunzl, K.; Hoetzl, H.; Rosner, G.; Winkler, R.

    1984-09-01

    To determine the effect of airborne emissions of radionuclides from coal-fired power plants on the environment, the concentrations of the most important radionuclides were measured in soil samples from the local environments (0.4-5.2 km) as well as in fly ash. The spatial distribution of the radionuclides in the soil did not indicate any significantly increased concentrations in the area downwind of the plant compared to other areas; the ratios lead 210/radium 226 and polonium 210/radium 226 were within the range observed for unaffected soils. The emissions from the plant, though present, are obviously too small to significantly change the natural local distribution pattern of the radionuclides in the soil. A highly significant correlation between potassium 40 and thorium 232 was observed which was independent of the different types of soils found in this area. The concentration of cesium 137 in topsoil, which is the result of worldwide fallout from nuclear weapons testing, varied at some places even within a small distance (approx. 2 km) by up to one order of magnitude. Furthermore, it was observed that the concentration of cesium 137 in soils from cropland was on average a factor of 2 less than in those from grassland. This variability has to be considered in planning monitoring programs around nuclear power plants, which may also release this radionuclide. (A.V.)

  14. Water-sediment distribution and behaviour of Polonium ("2"1"0Po) in a shallow coastal area with high concentration of dissolved organic matters in water, North Vietnam

    International Nuclear Information System (INIS)

    Tran Thi Van; Nguyen Duc Tam; Dang Duc Nhan; Nguyen Quang Long; Duong Van Thang; Bui Duy Cam

    2016-01-01

    The behaviour and water-sediment distribution of particle-reactive Polonium-210 in the marine environment with high concentration of total suspended particulates (TSP) and dissolved organic matters (DOC) along the coast of the Tonkin Gulf (North Vietnam) were investigated. It was revealed that the water-sediment distribution coefficient, K_d(s), of "2"1"0Po varied from 2.39x10"3 to 1.9x10"4 (L kg"-"1) and from 7x10"3 to 2.5x10"5 (L kg"-"1), respectively, in the rainy and dry season. This implies that in the aquatic environment "2"1"0Po tends to be of high affinity to suspended particulates. The "2"1"0Po K_d(s) was positively correlated with salinity in both rainy and dry seasons. With DOC the K_d(s) was positively correlated in the rainy season, but in the dry season the relationship tended to be reverse. This behaviour of "2"1"0Po in the coastal region was explained by the variation of pH of seawater and by the complexation of the isotope with DOC. The K_d(s) found in this study was in an order lower compared to that reported by Malaysian researchers for the Thailand Gulf. The most important source of "2"1"0Po was suggested to be from in-situ generation by the decay of its grand-parent "2"1"0Pb which mainly derived from the atmospheric fall-out. (author)

  15. Observation of the hot GDR in neutron-deficient thorium evaporation residues

    International Nuclear Information System (INIS)

    Seitz, J.P.; Back, B.B.; Carpenter, M.P.; Dioszegi, I.; Eisenman, K.; Heckman, P.; Hofman, D.J.; Kelly, M.P.; Khoo, T.L.; Mitsuoka, S.; Nanal, V.; Pennington, T.; Siemssen, R.H.; Thoennessen, M.; Varner, R.L.

    2005-01-01

    The giant dipole resonance built on excited states was observed in very fissile nuclei in coincidence with evaporation residues. The reaction 48 Ca+ 176 Yb populated evaporation residues of mass A=213-220 with a cross section of ∼200 μb at 259 MeV. The extracted giant dipole resonance parameters are in agreement with theoretical predictions for this mass region

  16. Deformation and shape transitions in hot rotating neutron deficient Te isotopes

    International Nuclear Information System (INIS)

    Aggarwal, Mamta; Mazumdar, I.

    2009-01-01

    Evolution of the nuclear shapes and deformations under the influence of temperature and rotation is investigated in Te isotopes with neutron number ranging from the proton drip line to the stability valley. Spin dependent critical temperatures for the shape transitions in Te nuclei are computed. Shape transitions from prolate at low temperature and spin to oblate via triaxiality are seen with increasing neutron number and spin.

  17. Beta-delayed proton emission in neutron-deficient lanthanide isotopes

    International Nuclear Information System (INIS)

    Wilmarth, P.A.

    1988-01-01

    Forty-two β-delayed proton precursors with 56≤Z≤71 and 63≤N≤83 were produced in heavy-ion reactions at the Lawrence Berkeley Laboratory SuperHILAC and their radioactive decay properties studied at the on-line mass separation facility OASIS. Twenty-five isotopes and eight delayed proton branches were identified for the first time. Delayed proton energy spectra and proton coincident γ-ray and x-ray spectra were measured for all precursors. In a few cases, proton branching ratios were also determined. The precursor mass numbers were determined by the separator, while the proton coincident x-ray energies provided unambiguous Z identifications. The proton coincident γ-ray intensities were used to extract final state branching ratios. Proton emission from ground and isomeric states was observed in many cases. The majority of the delayed proton spectra exhibited the smooth bell-shaped distribution expected for heavy mass precursors. The experimental results were compared to statistical model calculations using standard parameter sets. Calculations using Nilsson model/RPA β-strength functions were found to reproduce the spectral shapes and branching ratios better than calculations using either constant or gross theory β-strength functions. Precursor half-life predictions from the Nilsson model/RPA β-strength functions were also in better agreement with the measured half-lives than were gross theory predictions. The ratios of positron coincident proton intensities to total proton intensities were used to determine Q/sub EC/-B/sub p/ values for several precursors near N=82. The statistical model calculations were not able to reproduce the experimental results for N=81 precursors. 154 refs., 82 figs., 19 tabs

  18. Synthesis and properties of neutron deficient isotopes of elements around Z=100

    International Nuclear Information System (INIS)

    Antalic, S.

    2005-01-01

    In the presented Thesis work the results of spectroscopic studies of 246 Md, 247 Md, 254 Lr and 255 Lr decay chains are given. These isotopes were produced using heavy ion induced fusion reactions of 40 Ar + 209 Bi and 48 Ca + 209 Bi as a part of the long term project aimed to study spectroscopy properties of superheavy elements. The experiments were performed at velocity filter SHIP, placed at the central beam line of the UNILAC accelerator at GSI Darmstadt in Germany. The work also gives a basic overview of research in the region of superheavy elements, description of the used experimental setup and shows the usual analysis methods used in spectroscopic studies in the region of elements around Z ∼ 100. The results were obtained using α, α - γ spectroscopy methods and recoil - α, α - α correlations search. Although these isotopes have been known for a longer time, no detailed spectroscopy investigation were performed so far and only rough information was known. Beside the improved precision of known data, this work gives a new information about the decay properties of these isotopes. This give us the possibility to build a decay schemes for mentioned decay chains. (author)

  19. α-decay chain and associated cluster emission from neutron deficient 237Cf nucleus

    International Nuclear Information System (INIS)

    Jain, Deepika; Sharma, Manoj K.

    2015-01-01

    We have studied the α-decay chain of 237 Cf nucleus, which has been observed in the 3n evaporation channel when the semi-magic projectile 36 S strikes on 204 Pbv nucleus. The calculations are carried out by using preformed cluster model (PCM), with choices of spherical and quadruple deformation with in cold optimum orientation approach. The calculated half-lives of α-decay chain find relatively in nice agreement with experimental data for the deformed fragmentation approach. Along with α emission, the possibility of heavier clusters is also worked out and corresponding half-lives are predicted. (author)

  20. Direct mass measurements of neutron-deficient xenon isotopes with the ISOLTRAP mass spectrometer

    International Nuclear Information System (INIS)

    Dilling, J.; Audi, G.; Beck, D.; Bollen, G.; Henry, S.; Herfurth, F.; Kellerbauer, A.; Kluge, H.-J.; Lunney, D.; Moore, R.B.; Scheidenberger, C.; Schwarz, S.; Sikler, G.; Szerypo, J.

    2002-01-01

    The masses of Xe isotopes with 124≥A≥114 have been measured using the ISOLTRAP spectrometer at the on-line mass separator ISOLDE/CERN. A mass resolving power of 500 000 was chosen resulting in an accuracy of δm∼12 keV for all isotopes investigated. Conflicts with existing mass data of several standard deviations were found

  1. Direct mass measurements of neutron-deficient xenon isotopes using the ISOLTRAP mass spectrometer

    CERN Document Server

    Dilling, J; Beck, D; Bollen, G; Herfurth, F; Kellerbauer, A G; Kluge, H J; Moore, R B; Scheidenberger, C; Schwarz, S; Sikler, G

    2004-01-01

    The masses of the noble-gas Xe isotopes with 114 $\\leq$ A $\\leq$ 123 have been directly measured for the first time. The experiments were carried out with the ISOLTRAP triple trap spectrometer at the online mass separator ISOLDE/CERN. A mass resolving power of the Penning trap spectrometer of $m/\\Delta m$ of close to a million was chosen resulting in an accuracy of $\\delta m \\leq 13$ keV for all investigated isotopes. Conflicts with existing, indirectly obtained, mass data by several standard deviations were found and are discussed. An atomic mass evaluation has been performed and the results are compared to information from laser spectroscopy experiments and to recent calculations employing an interacting boson model.

  2. Probing shape coexistence in neutron-deficient $^{72}$Se via low-energy Coulomb excitation

    CERN Multimedia

    We propose to study the evolution of nuclear structure in neutron-­deficient $^{72}$Se by performing a low-­energy Coulomb excitation measurement. Matrix elements will be determined for low-­lying excited states allowing for a full comparison with theoretical predictions. Furthermore, the intrinsic shape of the ground state, and the second 0$^{+}$ state, will be investigated using the quadrupole sum rules method.

  3. A high-spin isomer at high excitation energy in the neutron deficient nucleus $^{152}$Dy

    CERN Document Server

    Jansen, J F W; Chmielewska, D; De Meijer, R J

    1976-01-01

    A T/sub 1/2/=60+or-5 ns isomer at E/sub x/ approximately=5 MeV is found in the /sup 154/Gd( alpha ,6n)/sup 152/Dy reaction. The possible spin values are 15

  4. Shape coexistence and shape isomerism in neutron-deficient mecury isotopes

    International Nuclear Information System (INIS)

    Proetel, D.

    1977-01-01

    The author investigates the electromagnetic decay of states in 188 Hg excited by both the EC decay of 188 Tl as well as (HI, xn) reactions. By conventional γ-ray and conversion electron spectroscopy using fast coincidence timing techniques and the pulsed HI beam relative branching ratios are established and upper limits set for half-lives of excited states in 188 Hg. (Auth.)

  5. Nuclear shape staggering in very neutron deficient Hg isotopes detected by laser spectroscopy

    International Nuclear Information System (INIS)

    Dabkiewicz, P.; Duke, C.; Fischer, H.; Kuehl, T.; Kluge, H.-J.

    1978-01-01

    The isotope shift in the lambda = 2537 A line of the even isotopes 206 Hg, 190 Hg, 188 Hg, 186 Hg, 184 Hg as well as of the I = 13/2 isomers of 191 Hg, 189 Hg, 187 Hg, 185 Hg has been measured by use of a tunable dye laser at the on-line masseparator ISOLDE at CERN. The resulting delta 2 > values follow the line, extrapolated from the chain 205 Hg- 187 Hg which is known to have spherical nuclear shape at the heavy end changing smoothly to slight oblate deformation for the lighter isotopes. Previous measurements of the I = 1/2 groundstates of 181 Hg. 183 Hg and 185 Hg revealed a sharp shape transition to strong deformation. Combined with the new results the following effects can be proved for the first time from the model-independent quantity delta 2 >: 1) the existence of odd even-shape staggering, 2) the coexistence of very different shapes in one and the same nucleus as manifested by the huge isomer shift in 185 Hg, 3) the absence of mixing of the different shapes. (author)

  6. Nuclear moments and the change of the mean square charge radius of neutron deficient thallium isotopes

    International Nuclear Information System (INIS)

    Menges, R.; Dinger, U.; Boos, N.; Huber, G.; Schroeder, S.

    1992-01-01

    The hyperfine structure, isotope and isomeric shifts in the atomic transition 6p 2 P 3/2 -7s 2 S 1/2 , λ=535 nm have been measured for the I=7 and I=2 states of 190,192,194,196 Tl, the I=1/2 and I=9/2 states of 191 Tl and the I=7 isomer of 188 Tl. The thallium isotopes were prepared as fast atomic beams at the GSI on-line mass separator following fusion reactions and - in some cases - subsequent β-decay. The nuclear dipole moments, electric quadrupole moments and the change in the nuclear mean square charge radius are evaluated. The uu-isotopes show an isomeric shift which changes sign between 192 Tl and 194 Tl. (orig.)

  7. Laser assisted nuclear decay spectroscopy: A new method for studying neutron-deficient francium

    CERN Document Server

    Lynch, Kara Marie

    2015-01-01

    Radioactive decay studies of rare isotopes produced at radioactive ion beam facilities have often been hindered by the presence of isobaric and isomeric contamination. The Collinear Resonance Ionization Spectroscopy (CRIS) experiment at ISOLDE, CERN uses laser radiation to stepwise excite and ionize an atomic beam in a particular isomeric state. Deflection of this selectively ionized beam of exotic nuclei, from the remaining neutral contaminants, allows ultra-sensitive detection of rare isotopes and nuclear structure measurements in background-free conditions.\

  8. Nuclear structure investigations of neutron deficient nuclei in the region Z=103 to 105

    International Nuclear Information System (INIS)

    Hessberger, F. P.; Hofmann, S.; Armbruster, P.; Muenzenberg, G.; Stodel, Ch.; Ackermann, D.; Lavrentev, A. Yu.; Popeko, A. G.; Yeremin, A. V.; Saro, S.; Leino, M.

    1999-01-01

    The isotopes 257,255 Rf, 257,256 Db, 253,252 Lr have been produced in bombardments of 207,208 Pb and 209 Bi target nuclei with 50 Ti and identified by their α-decay. New or improved decay data could be obtained. Analysis of the fine structure of the α-decay pattern of 257 Rf allowed the construction of a first tentative level scheme for the daughter nucleus 253 No and also the identification of a low lying high spin isomeric state, while from α-γ- coincidence measurements for 255 Rf a first tentative level scheme of the daughter nucleus 251 No was derived. For 257 Db we found that two nuclear levels decay by α-emission and populate also different levels in the daughter nucleus 253 Lr. The levels are produced by the reaction process. In bombardments of 209 Bi with 50 Ti at E CN *=26.4 MeV and 30.8 MeV the previously unknown isotopes 256 Db and 252 Lr were identified

  9. Beta strength distributions in neutron-deficient Kr and Sr isotopes using a total absorption spectrometer

    CERN Document Server

    Maréchal, F

    2003-01-01

    Far from the line of stability, beta -decay studies are often a primary source of information on nuclear structure. The measured beta -strength distribution for a given decay can be used to verify the accuracy of our theoretical description of the parent nucleus ground state and the states populated in the daughter nucleus. Total absorption spectrometers based on large NaI crystals are well suited tools to determine the beta -strength distribution over the whole Q /sub EC/ decay window. The newly built spectrometer TAgS, dedicated to such studies, is presented and its performances and possibilities are discussed in the light of experiments performed at the ISOLDE /CERN mass separator. The resulting information on ground state deformations for the /sup 74/Kr and /sup 76/Sr isotopes are discussed. (22 refs).

  10. Laser Spectroscopy Study on the Neutron-Rich and Neutron-Deficient Te Isotopes

    CERN Multimedia

    2002-01-01

    We propose to perform laser spectroscopy measurements on the Te isotopes. This will give access to fundamental properties of the ground and rather long-lived isomeric states such as the change in the mean square charge radius ($\\delta\\langle$r$^2_c\\rangle$) and the nuclear moments. For these medium-mass isotopes, at this moment the optical resolution obtained with RILIS is not high enough to perform isotope shift measurements. Thus we will use the COMPLIS experimental setup which allows Resonant Ionization Spectroscopy (RIS) on laser desorbed atoms. The 5p$^{4}$ $^{3}$P$_{2} \\rightarrow$ 5p$^{3}$ 6s $^{3}$S$_{1}$ and 5p$^{4}$ $^{3}$P$_{2} \\rightarrow$ 5p$^{3}$ 6s $^{5}$S$_{2}$ optical transitions have been used to perform, on the stable Te isotopes, the tests required by the INTC committee. For this purpose stable-ion sources have been built and Te isotopes have been delivered as stable beams by the injector coupled to the COMPLIS setup. ISOLDE offers the opportunity for studying the Te isotope series over a ...

  11. Uranium, radon-222 and polonium-210 in drinking waters from metropolitan area of Recife, PE, Brazil; Uranio, radonio-222 e polonio-210 em aguas de abastecimento publico da regiao metropolitana do Recife

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cleomacio Miguel da

    2000-04-01

    There is only scarce information on the presence of radionuclides in water for public consumption in Brazil. A recently issued federal regulation requires that waters from public supplies be screened to determine their content of alpha and beta emitters. In order to comply with this requirement the present work was carried out with the purpose of determining the concentration of natural uranium, {sup 222} Rn and {sup 210} Po in water supplies in the metropolitan region of Recife, Brazil. The analyses were performed in 17 points of supply of superficial water and 94 points of groundwater supply. The concentrations of uranium were determined by the fluorimetric method, whereas the liquid scintillation method was used to determine the concentration of {sup 222} Rn. Polonium-210, on the other hand, was determined by alpha spectrometry, following its spontaneous deposition on copper disks. The water analyzer presented uranium concentrations varying from 35.3 to 1146.5 mBq/L for superficial resources and from 20.2 to 919.15 mBq/L for underground sources. The concentration of uranium in superficial water showed significant correlation with some parameters such as conductivity, alkalinity and total hardness, as well as, with the concentrations of Ca, Mg, Cl, K, SO{sub 4} and Mn. No correlation, however, was shown with the concentrations of Fe, NO{sub 2} and NO{sub 3}. The concentrations of {sup 222} Rn varied from 5.3 to 83.7 Bq/L in the groundwater analyzer. Radon concentration was not measured in superficial water due to the high emanation rate of radon in open air conditions. As far as {sup 210} Po is concerned, the analyses showed concentrations ranging from <22 mBq/L (the lowest limit of detection) to 57.4 mBq/L for superficial water and from <22 to 813 mBq/L for ground water samples. The concentrations of {sup 210} Po did not show and correlation with physico-chemical parameters. The average concentrations of uranium and {sup 210} Po in superficial water were of 44

  12. Onset of deformation in polonium nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Younes, W.; Cizewski, J.A. [Rutgers Univ., New Brunswick, NJ (United States)

    1996-12-31

    The authors have been able to reproduce the systematics of the positive-parity states in {sup 192-208}Po within the framework of the Particle-Core Model. The wave-functions of the 2{sup +}{sub 1} states have been extracted using the Quasiparticle Random Phase Approximation. The increase in the collective motion of the lighter isotopes comes from the increased proton-neutron interaction when the neutrons and protons both occupy high-j orbitals.

  13. The Litvinenko 210polonium case. German experiences

    International Nuclear Information System (INIS)

    Kroeger, Emily Alice

    2009-01-01

    The high scientific standards of the BfS were necessary in order to characterize and evaluate the low activities of 210 Po found during the deployment in Hamburg. The evaluation of the measurements enabled the BfS to offer effective radiation protection advice and to assist the police investigation. The majority of the 210 Po traces were found in places that had been in skin contact with Kovtun, leading to the conclusion that Kovtun had most probably incorporated 210 Po before his visit to Hamburg in October 2006. As yet, no formal charges have been brought by the German authorities against Kovtun and the costs of the operation remain under discussion. Strategies to improve the internal and external deployment communication of the ZUB are being developed and implemented to deal with both the real and the perceived threats that occur during such an incident. Open communication from the onset of a deployment is essential, both between the institutions involved and between deployment leaders and the press. This will save precious time and resources, lower anxiety in the public and emergency workers and could, in a culture of trust where radiation protection advice is listened to and followed, ultimately save lives. (orig.)

  14. Polonium-210 as Weapon for Mass Destruction

    International Nuclear Information System (INIS)

    Koteng, A.O.

    2010-01-01

    Properties of Po-210 make it possible for its use as weapon of mass destruction. Po-210 occurs naturally in minute quantities in the human body, in Uranium ore (< 0.1 mg Po-210 / ton ) and as a product of Radon-222 gas decay chain. Po-210 also occurs as deposition on vegetation (tobacco leaves). Po-210 is produced by bombardment of Bi-209 with neutrons in a nuclear reactor. Russia produces 8 grams per year for export to USA market

  15. Polonium-210 in Euphauslids: A Detailed Study

    Energy Technology Data Exchange (ETDEWEB)

    Heyraud, M.; Fowler, S. W.; Beasley, T. M.; Cherry, R. D.

    1976-07-01

    A detailed study of {sup 210}Po, the predominant alpha-emitting nuclide found in most marine organisms, has been undertaken in a particular zooplanktonic species, the euphausiid Meganyctiphanes norvegica. The purpose was to obtain information concerning the origin, the localization and the flux of the nuclide in and through this organism. Measurements of {sup 210}Po were made in euphausiids of different sizes, in dissected organs and tissues, and in excretion products. The results show higher concentrations in the smaller specimens; this fact cannot be explained on the basis of surface adsorption, but is probably related to the ingestion of food. Dissection results show that the distribution of {sup 210}Po in euphausiids is not homogeneous, but that the majority is concentrated in the internal organs, the alimentary tract and the hepatopancreas in particular. The natural radiation dose received by these organs is in consequence much higher than that received by the whole animal. Use of a dynamic model allowed the flux of {sup 210}Po through M. norvegica to be calculated. The calculations confirm that food is the principal sauce of {sup 210}Po for this species, and clearly show that fecal pellets constitute the major elimination route. Extrapolation of the data to zooplankton in general leads to the conclusion that zooplankton metabolic activity plays an important role in transporting {sup 210}Po from the surface layers of the ocean to depth. (author)

  16. Polonium-210 in Euphauslids: A Detailed Study

    International Nuclear Information System (INIS)

    Heyraud, M.; Fowler, S.W.; Beasley, T.M.; Cherry, R.D.

    1976-01-01

    A detailed study of 210 Po, the predominant alpha-emitting nuclide found in most marine organisms, has been undertaken in a particular zooplanktonic species, the euphausiid Meganyctiphanes norvegica. The purpose was to obtain information concerning the origin, the localization and the flux of the nuclide in and through this organism. Measurements of 210 Po were made in euphausiids of different sizes, in dissected organs and tissues, and in excretion products. The results show higher concentrations in the smaller specimens; this fact cannot be explained on the basis of surface adsorption, but is probably related to the ingestion of food. Dissection results show that the distribution of 210 Po in euphausiids is not homogeneous, but that the majority is concentrated in the internal organs, the alimentary tract and the hepatopancreas in particular. The natural radiation dose received by these organs is in consequence much higher than that received by the whole animal. Use of a dynamic model allowed the flux of 210 Po through M. norvegica to be calculated. The calculations confirm that food is the principal sauce of 210 Po for this species, and clearly show that fecal pellets constitute the major elimination route. Extrapolation of the data to zooplankton in general leads to the conclusion that zooplankton metabolic activity plays an important role in transporting 210 Po from the surface layers of the ocean to depth. (author)

  17. Polonium-210 in euphausiids: a detailed study

    Energy Technology Data Exchange (ETDEWEB)

    Heyraud, M; Fowler, S W; Beasley, T M; Cherry, R D

    1976-02-13

    A detailed study of /sup 210/Po, the predominant alpha-emitting nuclide found in most marine organisms, has been undertaken in a particular zooplanktonic species, the euphausiid Meganyctiphanes norvegica. Information was obtained concerning the origin, the localization and the flux of the nuclide in and through the organism. Measurements of /sup 210/Po were made in euphausiids of different sizes, in dissected organs and tissues, and in excretion products. The results show higher concentrations in the smaller specimens; this fact cannot be explained on the basis of surface adsorption, but is probably related to the ingestion of food. Dissection results show that the distribution of /sup 210/Po in euphausiids is not homogeneous, but that the majority is concentrated in the internal organs, the alimentary tract and the hepatopancreas in particular. The natural radiation dose received by these organs is in consequence much higher than that received by the whole animal. Use of a dynamic model allowed the flux of /sup 210/Po through M. norvegica to be calculated. The calculations confirm that food is the principal source of /sup 210/Po for this species, and clearly show that fecal pellets constitute the major elimination route. Extrapolation of the data to zooplankton in general leads to the conclusion that zooplankton metabolic activity plays an important role in transporting /sup 210/Po from the surface layers of the ocean to depth. (auth)

  18. Nuclear structure from radioactive decay

    International Nuclear Information System (INIS)

    Wood, J.L.

    1991-01-01

    This report discusses nuclear structure from radioactive decay of the following: Neutron-Deficient Iridium Isotopes; Neutron-Deficient Platinum Isotopes; Neutron-Deficient Gold Isotopes; Neutron-Deficient Mercury Isotopes; Neutron-Deficient Thallium Isotopes; Neutron-Deficient Lead Isotopes; Neutron-Deficient Samarium Isotopes; Neutron-Deficient Promethium Isotopes; Neutron-Deficient Neodymium Isotopes; and Neutron-Deficient Praseodymium Isotopes. Also discussed are Nuclear Systematics and Models

  19. Estimates of fission barrier heights for neutron-deficient Po to Ra nuclei produced in fusion reactions

    Directory of Open Access Journals (Sweden)

    Sagaidak Roman

    2017-01-01

    Full Text Available The cross section data for fission and evaporation residue production in fusion reactions leading to nuclei from Po to Ra have been considered in a systematic way in the framework of the conventional barrier-passing (fusion model coupled with the statistical model. The cross section data obtained in very asymmetric projectile-target combinations can be described within these models rather well with the adjusted model parameters. In particular, one can scale and fix the macroscopic (liquid-drop fission barrier heights (FBHs for nuclei involved in the de-excitation of compound nuclei produced in the reactions. The macroscopic FBHs for nuclei from Po to Ra have been derived in the framework of such analysis and compared with the predictions of various theoretical models.

  20. Production of neutron deficient rare isotope beams at IGISOL; on-line and off-line studies

    NARCIS (Netherlands)

    Huikari, J; Dendooven, P; Jokinen, A; Nieminen, A; Penttila, H; Perajarvi, K; Popov, A; Rinta-Antila, S; Aysto, J

    This article reports on recent on-line yield measurements employing the light-ion and heavy-ion reaction-based ion guide systems and new results on a-recoil ion transport properties in ion guides with and without electric fields. In addition, the presently used ion guide designs for fusion

  1. Collective excitations at low energy: microscopic study of rotation, vibration and their coupling in even-even nuclei; Excitations collectives a basse energie: Etude microscopique de la rotation, de la vibration et de leur couplage dans les noyaux pair-pairs

    Energy Technology Data Exchange (ETDEWEB)

    Deloncle, I.

    1989-10-23

    In this study we have built the quadrupolar collective Bohr Hamiltonian in a purely microscopic way by using an approximation of the time-dependant Hartree-Fock adiabatic approach. The purpose of this work was to obtain a quantitative description of the collective properties in the low energy range of intermediate and heavy nuclei by using a 2-body effective interaction of Skyrme-type. We consider low energy processes as dynamic regimes in which the collective movement is adiabatic when compared with modes associated to individual freedom. In the N-body solution we propose, we have assumed that: -) a mean field exists at any moment, -) some collective variables exist whose temporal variations include all the dynamics, and -) the collective movement is adiabatic. This work is a microscopic formulation and an efficient approach to resolve the Bohr and Mottelson unified model. Low energy spectra have been computed for 4 nuclei: Ge{sup 74}, Se{sup 76}, Cd{sup 110} and Pt{sup 186} and they agree well with experimental data.

  2. $\\beta$-delayed fission, laser spectroscopy and shape-coexistence studies with radioactive At beams

    CERN Multimedia

    We propose to study the $\\beta$-delayed fission, laser spectroscopy and radioactive decay of the newly available pure beams of neutron-deficient and neutron-rich astatine (Z=85) isotopes. The fission probability and the fission fragment distribution of the even-even isotopes $^{194,196}$Po following the $\\beta$-decay of the isotopes $^{194,196}$At will be studied with the Windmill setup. In-source laser spectroscopy will be performed on the entire astatine isotopic chain, using a combination of the Windmill setup, ISOLTRAP MR-ToF and ISOLDE Faraday. Radioactive decay data will be acquired at the Windmill setup throughout those studies and contribute to the global understanding of the phenomenon of shape coexistence in the neutron-deficient lead region.

  3. The London polonium poisoning: Events and medical implications

    International Nuclear Information System (INIS)

    Perkins, A.C.

    2007-01-01

    The poisoning of Alexander Litvinenko on 23 November 2006 was an unprecedented event. Po-210 is a highly toxic radioactive heavy metal with a physical half-life of 138 days. Dispersal of the material by the perpetrators and the victim resulted in widespread contamination that led to a trail across London and abroad. This resulted in a massive operation for health protection staff and the police service. The surreptitious nature of this act almost escaped detection. The fact that the nature of the poison was not known for a number of weeks after admission to hospital indicates the difficulty in detecting alpha radiation. In this article, the sequence of events, the nature and uses of this radioactive element and the medical consequences of ingestion are outlined. The illicit use of radioactive materials raises important health and security issues. Medical and scientific staff in nuclear medicine and hospital emergency departments should be aware of these issues. (author)

  4. Management of response to the polonium-210 incident in London

    International Nuclear Information System (INIS)

    Croft, John; Bailey, Michael; Tattersall, Phil; Morrey, Mary; McColl, Neil; Prosser, Lesley; Maguire, Helen; Fraser, Graham; Gross, Roger

    2008-01-01

    On the 23 November 2006, Alexander Litvinenko died in London allegedly from poisoning by 210 Po, an alpha particle emitter. The spread of radioactive contamination, arising from the poisoning and the events leading up to it, involved many locations in London. The potential for intakes of 210 Po arising from the contamination posed a public health risk and generated significant public concern. The scale of the event required a multi-agency response, including top level UK Government emergency response management arrangements. The Health Protection Agency (HPA) had a leading role in co-ordinating and managing the public health response. This paper reviews the management of the incident response and the issues involved. The fatal poisoning of Mr Litvinenko with 210 Po, and the associated public health hazard from the spread of contamination to many locations across London, was an unprecedented event. Fortunately, no one else is known to have suffered any acute effects. Results from the programme of individual monitoring showed that whilst more than 100 people had measurable intakes of 210 Po, only 17 had assessed doses in excess of 6 mSv. The highest dose of about 100 mSv gives rise to an increased risk of fatal cancer of about 0.5%, compared with the natural incidence of about 25%. The incident required a co-ordinated and sustained multi-agency emergency response. The Health Protection Agency, as the lead on public health matters played a significant role in this. Whilst inevitably some lessons have been identified, the response is considered to have been very effective and to have benefited from the wide spectrum of experience and expertise developed through normal work, together with the effort put into emergency preparedness and the various emergency response. (author)

  5. Absorption of environmental polonium-210 by the human gut

    International Nuclear Information System (INIS)

    Hunt, G.J.; Allington, D.J.

    1993-01-01

    Current values for the gut absorption factor of plutonium- 210 ( 210 Po) are based on very few human data, yet the dose due to 210 Po is an important component of the dose to man through food as a result of natural sources of radiation. In this study, three male and three female adult volunteers ate supplies of brown crab meat containing natural concentrations of 210 Po, which are analysed from sub-samples. Daily urine and faecal samples, taken for 3 days before and up to 3 weeks after ingestion, were also analysed. Values of apparent absorption were derived from the faecal measurements; estimates of the true absorption were derived taking account of endogenous faecal excretion on the basis of existing data for intravenous administration. The results appear to suggest that the gut absorption factor in current use for 210 Po (in connection with ingestion in food) should be increased from 0.1-03 to about 0.8. The implications for estimates of dose due to this exposure pathway are noted. (author)

  6. Polonium radioactivity in tobacco and its cancer risk in smokers

    International Nuclear Information System (INIS)

    Muramatsu, Susumu

    1976-01-01

    Radioactivity levels by the fission of radium series were different in regions and seasons. Accordingly, amounts of 210 Po were different in these environments, and it transfered into tobacco leaves of raw material. Furthermore, amount of 210 Po in tobacco leaves was changed a little by manufacturing process of tobacco after the harvesting, and 210 Po was concentrated in the manufactured goods. 210 Po in tobacco was absorbed into human body by smoking, was transfered into the lung, and was accumulated. Accumulated 210 Po releases alpha ray and becomes low accumulated dose. When this low accumulated dose distributes out of balance in the body, it becomes large exposure dose at some local sites, and makes a problem of carcinogenesis risk. The above-mentioned process were persuied from the data of literatures and were discussed. (Kanao, N.)

  7. Fission of polonium, osmium, and erbium composite systems

    NARCIS (Netherlands)

    Plicht, J. van der; Britt, H.C.; Fowler, M.M.; Fraenkel, Z.; Gavron, A.; Wilhelmy, J.B.; Plasil, F.; Awes, T.C.; Young, G.R.

    1983-01-01

    Fission cross section excitation functions were measured from near threshold to ~10 MeV/nucleon using 9Be, 12C, 16,18O, 24,26Mg, 32S, and 64Ni beams. The systems studied included 210Po formed in 12C and 18O induced reactions; 186Os formed in 9Be, 12C, 16O, and 26Mg reactions; and 158Er formed in

  8. Deep penetration of polonium implanted in cadmium sulfide

    International Nuclear Information System (INIS)

    Weinmann, E.

    1975-01-01

    The distribution of 25 keV 210 Po implanted into CdS platelets was determined by means of energy analysis of the α-particles emitted by the 210 Po. Two samples were implanted along an axial channeling direction, and one along a planar channeling direction. The resulting distributions did not conform to any of the existing range theories or, in the case of axial channeling, to existing diffusion theories. A new diffusion model was formulated and fitted to the experimental data. Good agreement was obtained between this model and experiment for both the axial and the planar channeling conditions. The stopping power of CdS for He ions was measured as a preliminary step to the Po distribution measurement. A new technique was used which consisted in measuring the energy spectrum of either He ions backscattered from Bi implanted in CdS or of α-particles emitted by 210 Po implanted in CdS. A thin layer was then etched off the surface of the sample and the energy spectrum was measured again. The stopping power was calculated from these two spectra and the known thickness of the removed layer. These measurements and calculations were made for energies ranging from 0.963 to 5.3 MeV with accuracies between 12 percent and 16 percent

  9. Fetal doses from plutonium-239 and polonium-210

    International Nuclear Information System (INIS)

    Harrison, J.D.; Morgan, A.; Stather, J.W.

    1992-01-01

    The transfer of 239 Pu and 210 Po from the maternal circulation to the developing embryo and fetus was studied in rodents. The highest concentrations of both isotopes were measured in the yolk sac. In utero doses to haemopoietic tissue have been calculated taking account of transfer to the blastocyst/egg cylinder, yolk sac, liver and bone marrow. From animal data, the concentration ratios relative to maternal liver for these tissues were taken to be 0.1, 2, 0.01 and o.02, respectively for 239 Pu; and 1, 2, 0.1 and 0.1, respectively, for 210 Po. These concentration ratios were applied to periods of human gestation of 0-2.5 weeks, 2.5-6 weeks, 6-12 weeks and 12-38 weeks, and used to calculate fetal tissue doses for chronic maternal intake by ingestion of 1 kBq 239 Pu or 2 kBq 210 Po in the year of pregnancy (1 ALI for a member of the public). On this basis, the total in utero dose to haemopoietic tissue was about 1 μSv from 239 Pu and 60 μSv from 210 Po compared with red bone marrow doses to the mother in the year of 19 μSv from 239 Pu and 160 μSv from 210 Po. The yolk sac and bone marrow dominated in utero doses from both nuclides. For 239 Pu, because of its long half life, an important consideration was activity present in the offspring at birth and committed dose equivalents to red bone marrow in the child and mother. The total dose to haemopoietic tissue in the offspring to age 70 years, including in utero doses, was calculated as 13 μSv compared with a maternal dose to red bone marrow of 1400 μSv. For both isotopes the risk of leukaemia in the year of pregnancy was estimated to be of the same order for mother and fetus. For 239 Pu, the overall risk to 70 years of age was two orders of magnitude higher for the mother than her offspring. For 239 Pu, an acute intake of 1 kBq by ingestion during the period of yolk sac haemopoiesis would result in the highest in utero dose, estimated at about 20 μSv. However, activity at birth would be lower and the overall risk would be similar to the risk after chronic intake. (Author) 8 tabs., 39 refs

  10. Research on polonium-218 survey technique for uranium

    International Nuclear Information System (INIS)

    Zhou, R.

    1985-01-01

    This article makes an exposition of the principles and procedures of 218 Po survey technique for uranium. The experiments done with 218 Po method on a large scale on the deposits of granite, volcanic rock and carbon-silliceous slate types showed that the method of not only as effective as track method and 210 Po method, but also has the characteristics of its own. The device has higher working efficiency with only 5 minutes needed at each measurement point, and its sensitivity is higher, about 0.7 pulse/136.S (P ci /L). The results of measurement by 218 Po method will not be affected by thorium emanation and there will be no contamination of the scintillation chamber by radon daughter. The ratio of anomalous peak value to the bottom for 218 Po method is proved to be higher than that for track method and 210 Po method. In order to avoid the influence of moisture, the measurement by 218 Po method should be planned to do when it is not a rainy day and the holes must be dug some distance off the ditches and rice fields, thus ensuring the success in applying the method

  11. Polonium-210 and lead-210 in marine food chains

    International Nuclear Information System (INIS)

    Heyraud, M.; Cherry, R.D.

    1979-01-01

    210 Po and 210 Pb have been measured systematically in whole animals, muscle and hepatopancreas of crustaceans and of molluscan cephalopods representative of a pelagic and benthic food chain. The same nuclides were also measured in liver, pyloric caecum, stomach contents and muscle of tuna. The concentration factors from sea water to whole animals were approximately constant along both food chains, being of the order of 10 4 for 210 Po and 10 2 for 210 Pb. The highest concentration factors were found in shrimp of the genus Sergestes. In muscle, the concentration factors were an order of magnitude less; in the hepatopancreas, they were an order of magnitude higher, reaching 10 6 in shrimp of the genus Sergestes. Such concentrations imply alpha-radiation doses of the order of 10 rem per year and more in this organ, which contains about 50 to 90% of the 210 Po in the whole animal in the 11 species analyzed. A detailed study of the intracellular behaviour of 210 Po in the hepatopancreas is clearly indicated. 210 Po can be used as a sensitive natural tracer in biological systems. Thus, feeding Meganyctiphanes norvegica in the laboratory on food low in 210 Po led to an approximate value of about 6 1/2 days for the biological half-life of 210 Po in the hepatopancreas of this euphausiid. Furthermore, the data on 210 Po and 210 Pb in the cephalopod hepatopancreas allowed the time of conservation of frozen squid which had been bought at the market to be estimated. (orig.) 891 AJ/orig. 892 MKO [de

  12. Polonium radioactivity in tobacco and its cancer risk in smokers

    Energy Technology Data Exchange (ETDEWEB)

    Muramatsu, S [National Inst. of Radiological Sciences, Chiba (Japan)

    1976-07-01

    Radioactivity levels by the fission of radium series were different in regions and seasons. Accordingly, amounts of /sup 210/Po were different in these environments, and it transfered into tobacco leaves of raw material. Furthermore, the amount of /sup 210/Po in tobacco leaves was changed a little by manufacturing process of tobacco after the harvesting, and /sup 210/Po was concentrated in the manufactured goods. The /sup 210/Po in tobacco was absorbed into the human body by smoking, was transfered into the lung, and was accumulated. Accumulated /sup 210/Po releases alpha ray and becomes low accumulated dose. When this low accumulated dose distributes out of balance in the body, it becomes large exposure dose at some local sites, and makes a problem of carcinogenesis risk. The above-mentioned process was persued from the data of literature and was discussed.

  13. Absorption of environmental polonium-210 by the human gut

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, G J; Allington, D J [Ministry of Agriculture, Fisheries and Food, Lowestoft (United Kingdom). Fisheries Radiobiological Lab.

    1993-06-01

    Current values for the gut absorption factor of plutonium- 210 ([sup 210]Po) are based on very few human data, yet the dose due to [sup 210]Po is an important component of the dose to man through food as a result of natural sources of radiation. In this study, three male and three female adult volunteers ate supplies of brown crab meat containing natural concentrations of [sup 210]Po, which are analysed from sub-samples. Daily urine and faecal samples, taken for 3 days before and up to 3 weeks after ingestion, were also analysed. Values of apparent absorption were derived from the faecal measurements; estimates of the true absorption were derived taking account of endogenous faecal excretion on the basis of existing data for intravenous administration. The results appear to suggest that the gut absorption factor in current use for [sup 210]Po (in connection with ingestion in food) should be increased from 0.1-03 to about 0.8. The implications for estimates of dose due to this exposure pathway are noted. (author).

  14. Polonium-210 and lead-210 in marine food chains

    Energy Technology Data Exchange (ETDEWEB)

    Heyraud, M [Musee Oceanographique (Monaco). International Lab. of Marine Radioactivity; Cherry, R D [Cape Town Univ. (South Africa). Dept. of Physics

    1979-01-01

    /sup 210/Po and /sup 210/Pb have been measured systematically in whole animals, muscle and hepatopancreas of crustaceans and of molluscan cephalopods representative of a pelagic and benthic food chain. The same nuclides were also measured in liver, pyloric caecum, stomach contents and muscle of tuna. The concentration factors from sea water to whole animals were approximately constant along both food chains, being of the order of 10/sup 4/ for /sup 210/Po and 10/sup 2/ for /sup 210/Pb. The highest concentration factors were found in shrimp of the genus Sergestes. In muscle, the concentration factors were an order of magnitude less; in the hepatopancreas, they were an order of magnitude higher, reaching 10/sup 6/ in shrimp of the genus Sergestes. Such concentrations imply alpha-radiation doses of the order of 10 rem per year and more in this organ, which contains about 50 to 90% of the /sup 210/Po in the whole animal in the 11 species analyzed. A detailed study of the intracellular behaviour of /sup 210/Po in the hepatopancreas is clearly indicated. /sup 210/Po can be used as a sensitive natural tracer in biological systems. Thus, feeding Meganyctiphanes norvegica in the laboratory on food low in /sup 210/Po led to an approximate value of about 6 1/2 days for the biological half-life of /sup 210/Po in the hepatopancreas of this euphausiid. Furthermore, the data on /sup 210/Po and /sup 210/Pb in the cephalopod hepatopancreas allowed the time of conservation of frozen squid which had been bought at the market to be estimated. (orig.) 891 AJ/orig. 892 MKO.

  15. Polonium-210 and lead-210 in marine organisms

    International Nuclear Information System (INIS)

    Yamamoto, M.; Kuwabara, J.; Komura, K.; Ueno, K.

    1994-01-01

    The concentrations of 210 Po and 210 Pb were determined in about 30 species of marine organisms collected mainly from the north-eastern region of Japan to know the levels and distributions of these radionuclides and to estimate their intake levels from marine foods. 210 Po and 210 Pb showed a wide range of concentration in species: 0.6-26 and 0.04-0.54 Bq/kg (wet wt) in fishes, 0.5-220 and 0.2-43 Bq/kg (wet wt) in molluscs, echinoderms and chordatas, and 2.8-4.3 and 0.4-1.3 Bq/kg (wet wt) in algae, respectively. Higher accumulation of 210 Po relative to 210 Pb was found in all of the samples analyzed. The intake levels of 210 Po and 210 Pb by marine foods consumption were roughly estimated to be 0.48-0.69 and 0.022-0.042 Bq/d per person, respectively, on the basis of the statistical data on the consumption of seafood and/or production rates of marine foods. (author) 16 refs.; 6 tabs

  16. Content of polonium-210 in food products of Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    Keslev, D; Novakova, E; Boyadzhiev, A; Kerteva, A

    1975-01-01

    Most of the Po-210 entering the human organism is associated with food products. The content of Po-210 in various food products is given as follows in picocuries/kg: 0.88 for meat, 1.25 for milk, 2.75 for bread, 0.19 for egg (content in one egg), 6.70 for wheat, 1.27 for corn, 0.90 for potatoes, 1.20 for beans, 1.84 for cabbage, 1.26 for tomatoes, 1.64 for pepper, 0.50 for onions, 1.2 for apples, 1.35 for pears, 2.20 for prunes, 1.24 for grapes and 0.07 for water. The data compare well with literature data. The daily intake of Po-210 with the diet varies from 1.61 to 2.08 picocuries for different age groups of individuals. Most of this amount is eliminated via the urine (70 to 80%) and the feces. 9 refs. (SJR)

  17. Polonium-210 in the total environment of Goa

    International Nuclear Information System (INIS)

    Avadhani, D.N.; Mahesh, H.M.; Siddappa, K.

    2007-01-01

    The paper deals with the distribution of 210 Po in total environment of Goa. The activity concentration of 210 Po in food, diet, water and air samples of the region were measured and the annual effective dose due to ingestion of this radionuclide was estimated. The activity of 210 Po in soil and sand samples vary from 3.2 Bq kg -1 to 186.2 Bq kg -1 with a mean value of 57.4Bq kg -1 and from 0.94 Bq kg -1 to 3.7 Bq kg -1 with the mean value of 1.8 Bq kg -1 respectively. Among food samples fish and prawn shows higher concentration of 210 Po. The Committed Effective Dose Equivalent due to ingestion of non veg meal, veg meal, breakfast and potable water were found to be 94.6 μSv y -1 , 49.1 μSv y -1 , 10.5 μSv y -1 and 4.2 μSv y -1 respectively. All the results are compared with the reported literature values and discussed in detail in this paper. (author)

  18. Mass measurements on neutron-deficient nuclides at SHIPTRAP and commissioning of a cryogenic narrow-band FT-ICR mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Ferrer Garcia, R.

    2007-07-01

    The dissertation presented here deals with high-precision Penning trap mass spectrometry on short-lived radionuclides. Owed to the ability of revealing all nucleonic interactions, mass measurements far off the line of {beta}-stability are expected to bring new insight to the current knowledge of nuclear properties and serve to test the predictive power of mass models and formulas. In nuclear astrophysics, atomic masses are fundamental parameters for the understanding of the synthesis of nuclei in the stellar environments. This thesis presents ten mass values of radionuclides around A=90 interspersed in the predicted rp-process pathway. Six of them have been experimentally determined for the first time. The measurements have been carried out at the Penning-trap mass spectrometer SHIPTRAP using the destructive time-of-flight ion-cyclotron-resonance (TOF-ICR) detection technique. Given the limited performance of the TOF-ICR detection when trying to investigate heavy/superheavy species with small production cross sections ({sigma} <1 {mu}b), a new detection system is found to be necessary. Thus, the second part of this thesis deals with the commissioning of a cryogenic double-Penning trap system for the application of a highly-sensitive, narrow-band Fourier-transform ion-cyclotron-resonance (FT-ICR) detection technique. With the non-destructive FT-ICR detection method a single singly-charged trapped ion will provide the required information to determine its mass. First off-line tests of a new detector system based on a channeltron with an attached conversion dynode, of a cryogenic pumping barrier, to guarantee ultra-high vacuum conditions during mass determination, and of the detection electronics for the required single-ion sensitivity are reported. (orig.)

  19. High-precision mass measurements of neutron-deficient Tl isotopes at ISOLTRAP and the development of an ultra-stable voltage source for the PENTATRAP experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Christine

    2015-01-14

    Atomic masses and hence binding energies of nuclides are of great importance for studies of nuclear structure since they reflect all effective interactions in a nucleus. Within this thesis the masses of seven nuclides, namely {sup 194}Au, {sup 194}Hg, {sup 190,193,198}Tl and {sup 202,208}Pb, were determined at the Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The thallium region in the chart of isotopes is of special interest due to the occurrence of nuclear structure effects like low-lying isomers, level inversion, shape coexistence and deformations. These effects are investigated by applying finite-difference mass formulas, such as the two-neutron separation energies or the so-called empirical pairing gaps. The second topic addressed within the present thesis is an ultra-stable voltage source, called StaReP (Stable Reference for Penning Trap Experiments), which was developed at the Max-Planck-Institut fuer Kernphysik. It is one of the key components of the high-precision mass spectrometer PENTATRAP, containing a tower of five Penning traps. A 25-channel voltage source with a relative stability of few 10{sup -8} over a period of 10 minutes in the range of 0 to -100V is mandatory for PENTATRAP aiming for mass measurements with relative mass uncertainties of ≤ 10{sup -11}. Mass values with such a high precision allow for stringent tests of quantum electrodynamics in strong electric fields, testing Einstein's mass-energy relation E = mc{sup 2} as well as measurements of decay energies (Q-values) with applications in neutrino physics.

  20. Cold Fusion Production and Decay of Neutron-Deficient Isotopes of Dubnium and Development of Extraction Systems for Group V Elements

    Energy Technology Data Exchange (ETDEWEB)

    Gates, Jacklyn M. [Univ. of California, Berkeley, CA (United States)

    2008-07-31

    Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070$+1100\\atop{-760}$ pb was measured at an excitation energy of 16.0 ± 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660$+450\\atop{-370}$ pb was measured at 22.0 ± 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480$+1730\\atop{-1370}$ pb at an excitation energy of 16.0 ± 1.6 MeV. Differences in cross section maxima are discussed in terms of the fusion probability below the barrier. The extraction of niobium (Nb) and tantalum (Ta) from hydrochloric acid and mixed hydrochloric acid/lithium chloride media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) was studied. The goal of the experiments was to find a system that demonstrates selectivity among the members of group five of the Periodic Table and is also suitable for the study of dubnium (Db, Z = 105). Experiments with niobium and tantalum were performed with carrier (10-6 M), carrier free (10-10 M) and trace (10-16 M) concentrations of metal using hydrochloric acid solution with concentrations ranging from 1 - 11 M. The extraction of niobium and tantalum from mixed hydrochloric acid/lithium chloride media by HDEHP and BEHP as a function of hydrogen ion (H+) concentration was also investigated. The data obtained are used as the basis to discuss the speciation of niobium and tantalum under the conditions studied and to evaluate possible extraction mechanisms. The 74Se(18O,p3n)88gNb excitation function was measured to determine the best energy for producing the 88Nb used in chemistry experiments. A maximum cross section of 495 +- 5 mb was observed at an 18O energy of 74.0 MeV. The half life of 88gNb was measured and determined to be 14.56 ± 0.11 min.

  1. Coulomb excitation of $^{110}$Sn using REX-ISOLDE

    CERN Document Server

    Ekström, A; Hurst, A; Fahlander, C; Banu, A; Butler, P; Eberth, J; Górska, M; Habs, D; Huyse, M; Kester, O; Niedermayer, O; Nilsson, T; Pantea, M; Scheit, H; Schwalm, D; Sletten, G; Ushasi, D P; Van Duppen, P; Warr, N; Weisshaar, D

    2006-01-01

    In this paper, we report the preliminary result from the first Coulomb excitation experiment at REX-ISOLDE (Habs et al 1998 Nucl. Instrum. Methods B 139 128) using neutron-deficient Sn-beams. The motivation of the experiment is to deduce the reduced transition probability, B(E2 ; 2$^+\\rightarrow$ 0$^+$) , for the sequence of neutron deficient, unstable, even-even Sn-isotopes from using a radioactive beam opens up a new path to study the lifetime of the first excited 2$^+$ state in these isotopes. The de-excitation path following fusion-evaporation reactions will for the even-even Sn isotopes pass via an isomeric 6$^+$ state, located at higher energy, which thus hampers measurements of the lifetime of the first excited state using, e.g., recoil-distance methods. For this reason the reduced transition probability of the first excited 2$^+$ state has remained unknown in this chain of isotopes although the B(E2) value of the stable isotope $^{112}$Sn was measured approximately 30 years ago (see, e.g., Stelson et...

  2. Polonium-210 and lead-210 in edible molluscs from near the Cape of Good Hope: sources of variability in polonium-210 concentrations

    International Nuclear Information System (INIS)

    Heyraud, M.; Cherry, R.D.; Oschadleus, H.-D.; Cherry, M.I.; Sealy, J.C.

    1994-01-01

    Measurements of the natural radionuclides 210 Po and 210 Pb in mussels, squid and oysters from near the Cape of Good Hope are reported and compared with previously published 210 Po and 210 Pb data from Northern Hemisphere organisms in the same taxa. Emphasis is laid on discussing the causes of variability in the concentrations of 210 Po in marine organisms. No systematic evidence is found for a 'latitude' effect, but allometric effects, intertaxon differences, change of diet with animal size and regional effects are all significant for 210 Po. The consequences for human radiation dose calculations of variability of 210 Po levels in seafoods are discussed briefly; particular reference is made to the case of a Stone Age mussel-eating community in South Africa. (author)

  3. Coulomb excitation of {sup 107}Sn

    Energy Technology Data Exchange (ETDEWEB)

    DiJulio, D.D.; Cederkall, J.; Fahlander, C. [Lund University, Physics Department, 118, Lund (Sweden); Ekstroem, A. [University of Oslo, Department of Physics and Center of Mathematics for Applications, Oslo (Norway); Hjorth-Jensen, M. [University of Oslo, Department of Physics and Center of Mathematics for Applications, Oslo (Norway); Michigan State University, National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, East Lansing, MI (United States); Albers, M.; Blazhev, A.; Fransen, C.; Geibel, K.; Hess, H.; Reiter, P.; Seidlitz, M.; Taprogge, J.; Warr, N. [University of Cologne, Institute of Nuclear Physics, Cologne (Germany); Bildstein, V.; Gernhaeuser, R.; Wimmer, K. [Technische Universitaet Muenchen, Physik Department E12, Garching (Germany); Darby, I.; Witte, H. de [Instituut voor Kern- en Stralingsfysica, Leuven (Belgium); Davinson, T. [University of Edinburgh, Department of Physics and Astronomy, Edinburgh (United Kingdom); Diriken, J. [Instituut voor Kern- en Stralingsfysica, Leuven (Belgium); Studiecentrum voor Kernenergie/Centre d' Etude de l' energie Nucleaire (SCK CEN), Mol (Belgium); Goergen, A.; Siem, S.; Tveten, G.M. [University of Oslo, Department of Physics, Oslo (Norway); Iwanicki, J. [University of Warsaw, Heavy Ion Laboratory, Warsaw (Poland); Lutter, R. [Ludwig-Maximilians-Universitaet Muenchen, Fakultaet fuer Physik, Garching (Germany); Scheck, M. [University of Liverpool, Oliver Lodge Laboratory, Liverpool (United Kingdom); Walle, J.V. de [PH Department, Geneva 23 (Switzerland); Voulot, D.; Wenander, F. [AB Department, Geneva 23 (Switzerland)

    2012-07-15

    The radioactive isotope {sup 107}Sn was studied using Coulomb excitation at the REX-ISOLDE facility at CERN. This is the lightest odd-Sn nucleus examined using this technique. The reduced transition probability of the lowest-lying 3/2{sup +} state was measured and is compared to shell-model predictions based on several sets of single-neutron energies relative to {sup 100}Sn. Similar to the transition probabilities for the 2{sup +} states in the neutron-deficient even-even Sn nuclei, the measured value is underestimated by shell-model calculations. Part of the strength may be recovered by considering the ordering of the d{sub 5/2} and g{sub 7/2} single-neutron states. (orig.)

  4. Use of lead-210 and polonium-210 as tracers of atmospheric processes

    International Nuclear Information System (INIS)

    Nevissi, A.; Schell, W.R.

    1980-01-01

    The inputs of 210 Pb and 210 Po have been measured in two marine environments to trace atmospheric processes. Precipitation and dry fallout samples were collected monthly at Seattle, Wash., over a period of 4 years, and air filter samples were collected biweekly at the ground level on Amchitka Island, Alaska, over a period of 3 years. The results for both stations show that 210 Pb undergoes seasonal variations in surface deposition with minimum values in relatively dry months of summer and maximum values in the fall or winter. The seasonal variations of 210 Pb are attributed to several factors including: 210 Pb content of the air masses involved, changes in the meteorological conditions, and local input of 210 Pb as a result of radon exhalation and soil resuspension

  5. Radiological health implications of lead-210 and polonium-210 accumulations in LPG refineries

    International Nuclear Information System (INIS)

    Summerlin, J. Jr.; Prichard, H.M.

    1985-01-01

    Radon-222, a naturally occurring radioactive noble gas, is often a contaminant in natural gas. During fractionation at processing plants, Radon tends to be concentrated in the Liquified Petroleum Gas (LPG) product stream. Radon-222 decays into a number of radioactive metallic daughters which can plate out on the interior surfaces of plant machinery. The hazards associated with gamma-emitting short-lived radon daughters have been investigated previously. The present work reports an analysis of the hazards associated with the long-lived daughters; Pb-210, Bi-210, and Po-210. These nuclides do not emit appreciable penetrating radiation, and hence do not represent a hazard as long as they remain on the inside surfaces of equipment. However, when equipment that has had prolonged exposure to an LPG stream is disassembled for repair or routine maintenance, opportunities for exposure to radioactive materials can occur. A series of measurements made on an impeller taken from a pump in an LPG facility is reported. Alpha spectroscopy revealed the presence of Po-210, and further measurements showed that the amount on the impeller surface was well above the exempt quantity. Breathing zone measurements made in the course of cleaning the impeller showed that an inhalation exposure equivalent to breathing Po-210 at the Maximum Permissible Concentration (MPC) for 60 hours could be delivered in less than half an hour. It was concluded that maintenance and repair work on LPG and derivitive product stream equipment must be carried out with the realization that a potential radiological health problem exists

  6. A study on Polonium-210 distribution in the Koraiyar river ecosystem, Tiruchirappalli - India

    International Nuclear Information System (INIS)

    Krishnamoorthy, R.; Syed Mohamed, H.E.; Raja, P.; Shahul Hameed, M.M.; Shahul Hameed, P.

    2004-01-01

    The present work reports the distribution of naturally occurring alpha emitting radionuclide 210 Po in the environmental matrices of Koraiyar river. Koraiyar is a seasonal river and it is situated 5 Km West of Tiruchirappalli. Environmental samples such as water, sediment, plankton, weeds (Eichhornia crassipes), crab (Barytelphusa jacguemonti), gastropods (Pila virens and Bellamya dissimilis) and fishes (Anabas testudineus, Catla catla, Clarias batrachus, Channa punctatus, Macrognathus acculeatus, Mystus vittatus and Oreochromis mossambicus) were collected and subjected to the analyses of 210 Po activity. The concentration of 210 Po in water sample and sediment sample was 0.75 mBq/l and 3.1 Bq/Kg respectively. The roots and shoots of aquatic weeds and plankton sample showed concentration of 3.4, 1.2 and 22.2 Bq/Kg respectively. The concentration of 210 Po in crab muscle and exoskeleton was 43.92 Bq/Kg and 11.34 Bq/Kg respectively. In soft tissue of gastropods the 210 Po activity ranged from 38.16 (B. dissimilis) to 88.74 Bq/Kg (P. virens) and 2.9 to 9.45 Bq/Kg in shell. The 210 Po activity in fishes ranged from 8.87 (Macrognathus acculeatus) to 45.29 (Clarias batrachus) Bq/Kg in muscle and 4.76 to 25.09 Bq/Kg in bone. Concentration factor of 210 Po in edible portion of fish from river water ranged from 1.3 x 10 3 to 6.0 x 10 4 . Among the samples analysed P. virens accumulated higher concentrations of 210 Po and it could serve as a bioindicator organism in the absence of any bivalve mollusc. (author)

  7. A study on distribution of natural radionuclide polonium-210 in a pond ecosystem

    International Nuclear Information System (INIS)

    Shahul Hameed, P.; Shaheed, K.; Somasundaram, S.S.N.

    1997-01-01

    This paper presents the results of an investigation on the distribution of 210 Po in Mutharasanallur pond ecosystem. It has been demonstrated that 210 Po is non-uniformly distributed within the ecosystem. The results of the study show a dissolved 210 Po concentration in pond water of 1.4mBql -1 . The sediment sample recorded a 210 Po activity of 59.9 Bqkg -1 . The aquatic organism showed differential accumulation of the radionuclide with enhanced bioaccumulation in soft tissues and muscle. The 210 Po activity in the biota fell within the range of 1.2-53.3 Bqkg -1 (wet weight). The bivalve mussel, Lamellidens marginalis was identified to accumulate higher concentration of 210 Po in soft tissues, suggesting that these organisms could serve as a bio-monitor of 210 Po radionuclide in a freshwater system. The concentration factors of 210 Po for the biotic components ranged from ∼ 10 2 - ∼ 10 4 . Analyses of the results indicate that prawn and fish represent an important source of supply of 210 Po to humans via dietary intake. Results of 210 Po activity in the abiotic and biotic components of the pond ecosystem were higher when compared with those of Cauvery river system, the primary water source of the pond. (author)

  8. Measurement of the activity size distribution of the polonium-218 under laboratory conditions

    International Nuclear Information System (INIS)

    Yoon, Suk Chul; Ha, Chung Woo

    1992-01-01

    A number of investigators have reported the formation of the radiolytic ultrafine particles produced by the interaction of ionizing radiation with water vapor. Previous studies have suggested that a very high localized concentration of the OH radical produced by the radiolysis of water can react with trace gas like organic vapors and produce lower vapor pressure compounds that can then nucleate. In order to determine water vapor and trace gas dependence of the active, positive-charged, first radon daughter, an experiment was conducted using a radon chamber. The activity size distribution of the radon daughter in the range of 0.5 - 100 nm was measured using the stacked wire screens sampler. Measurements were taken for different relative humidity. The resultant activity size distributions were analyzed. The addition of water vapor to the radon carrier gases resulted in the formation of ultrafine particles by OH radicals formed radon radiolysis. It may be due to the neutralization of charged Po-218 ion with water vapor through the radiolysis

  9. Orientating investigation to Polonium-210 and other radionuclides in Dutch aquatic ecosystems

    International Nuclear Information System (INIS)

    Koester, H.W.; Marwitz, P.A.; Berger, G.W.; Weers, A.W. van; Hagel, P.; Nieuwenhuize, J.

    1990-08-01

    In 1985/86 reconnaissance investigations were carried out of Po-210, Pb-210, Ra-226, Th-230 of the U-238 series, and of Th-232 and its daughter Th-228. In the lower reaches of the Rhine, Westerschelde, and Hoogoven(furnace)-channel concentrations were markedly elevated. The average Po-210 concentrations of these waters were between 3-4 Bq.m -3 dissolved in water, between 200-500 Bq.kg -1 in dry suspended matter, between 300-400 Bq.kg -1 in mussels dry matter. These elevated levels could be ascribed to emissions on these waters by the phosphate rock and iron-ore-processing industries. In bottom sediment of waterways or of docks close to these industries Pb-210 and Po-210 concentrations varied from 150 to 750 Bq.kg -1 dry sediment. The lowest average Po-210 concentrations were found in the Oosterschelde: 0.8 Bq.m -3 dissolved in water, 70 Bq.kg -1 in dry suspended matter, 100 Bq.kg -1 in mussels dry matter. It was found that several organisms incorporate Po-210 more strongly than the other natural radionuclides. Po-210 also contributes most to the radiation burden caused by the consumption of fish products, in particular mussels and shrimps. Consumption of 1 kg. a -1 of shrimps from the Oosterschelde or from the coastal area causes respectively a radiation exposure of 10 μSv.a -1 or 30 μSv.a -1 . This study points out the necessity for further studies of the emissions of Po-210 and other U-238 daughters and their dispersal and/or accumulation in the aquatic environment. Furthermore it is important to identify critical groups with respect to the radiation exposure caused by the consumption of mussels and other fish products, and the contribution to this radiation exposure by the industries. (author). 43 refs.; 58 figs.; 52 tabs

  10. Polonium in Florida groundwater and its possible relationship to the sulfur cycle and bacteria

    International Nuclear Information System (INIS)

    Harada, K.; Burnett, W.C.; LaRock, P.A.; Cowart, J.B.

    1989-01-01

    The last radioactive member of the 238 U natural decay-series, 210 Po is normally considered a very particle-reactive isotope. Analysis of most natural waters shows that 210 Po is present at very low activities, usually even lower than its insoluble precursor, 210 Pb. The authors have recently discovered, however, that 210 Po exists at very high concentrations in groundwaters of some shallow aquifers in west central Florida. These waters tend to be fairly acidic (pH 222 Rn. Detailed study of one well with extraordinary levels of 210 Po (∼ 1000 dpm/l) indicates that: (1) 210 Po in this water is in great excess of radioactive equilibrium with its predecessors 210 Pb and 210 Bi; (2) most Po in this water exists in a form which does not coprecipitate with an iron hydroxide scavenge; and (3) the conversion of soluble (0.2 μm filter) to particulate Po occurs over a time scale of a few days during sulfide oxidation. The authors suspect that Po cycling in this environment is related to the sulfur cycle and may, therefore, be influenced by sulfur bacteria

  11. Polonium-210 and lead-210 in the terrestrial environment: a historical review

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Bertil R.R., E-mail: bertil_r.persson@med.lu.s [Dept. of Medical Radiation Physics, Lund University, Barngatan 2, SE-221 85 Lund (Sweden); Holm, Elis [Norwegian Radiation Protection Authority, Osteras (Norway)

    2011-05-15

    The radionuclides {sup 210}Po and {sup 210}Pb widely present in the terrestrial environment are the final long-lived radionuclides in the decay of {sup 238}U in the earth's crust. Their presence in the atmosphere is due to the decay of {sup 222}Rn diffusing from the ground. The range of activity concentrations in ground level air for {sup 210}Po is 0.03-0.3 Bq m{sup -3} and for {sup 210}Pb 0.2-1.5 Bq m{sup -3}. In drinking water from private wells the activity concentration of {sup 210}Po is in the order of 7-48 mBq l{sup -1} and for {sup 210}Pb around 11-40 mBq l{sup -1}. From water works, however, the activity concentration for both {sup 210}Po and {sup 210}Pb is only in the order of 3 mBq l{sup -1}. Mosses, lichens and peat have a high efficiency in capturing {sup 210}Po and {sup 210}Pb from atmospheric fallout and exhibit an inventory of both {sup 210}Po and {sup 210}Pb in the order of 0.5-5 kBq m{sup -2} in mosses and in lichens around 0.6 kBq m{sup -2}. The activity concentrations in lichens lies around 250 Bq kg{sup -1}, dry mass. Reindeer and caribou graze lichen which results in an activity concentration of {sup 210}Po and {sup 210}Pb of about 1-15 Bq kg{sup -1} in meat from these animals. The food chain lichen-reindeer or caribou, and Man constitutes a unique model for studying the uptake and retention of {sup 210}Po and {sup 210}Pb in humans. The effective annual dose due to {sup 210}Po and {sup 210}Pb in people with high consumption of reindeer/caribou meat is estimated to be around 260 and 132 {mu}Sv a{sup -1} respectively. In soils, {sup 210}Po is adsorbed to clay and organic colloids and the activity concentration varies with soil type and also correlates with the amount of atmospheric precipitation. The average activity concentration levels of {sup 210}Po in various soils are in the range of 20-240 Bq kg{sup -1}. Plants become contaminated with radioactive nuclides both by absorption from the soil (supported Po) and by deposition of radioactive fallout on the plants directly (unsupported Po). In fresh leafy plants the level of {sup 210}Po is particularly high as the result of the direct deposition of {sup 222}Rn daughters from atmospheric deposition. Tobacco is a terrestrial product with high activity concentrations of {sup 210}Po and {sup 210}Pb. The overall average activity concentration of {sup 210}Po is 13 {+-} 2 Bq kg{sup -1}. It is rather constant over time and by geographical origin. The average median daily dietary intakes of {sup 210}Po and {sup 210}Pb for the adult world population was estimated to 160 mBq day{sup -1} and 110 mBq day{sup -1}, corresponding to annual effective doses of 70 {mu}Sv a{sup -1} and 28 {mu}Sv a{sup -1}, respectively. The dietary intakes of {sup 210}Po and {sup 210}Pb from vegetarian food was estimated to only 70 mBq day{sup -1} and 40 mBq day{sup -1} corresponding to annual effective doses of 30.6 {mu}Sv a{sup -1} and 10 {mu}Sv a{sup -1}, respectively. Since the activity concentration of {sup 210}Po and {sup 210}Pb in seafood is significantly higher than in vegetarian food the effective dose to populations consuming a lot of seafood might be 5-15 fold higher.

  12. Polonium-210 and Caesium-137 in lynx (Lynx lynx), wolverine (Gulo gulo) and wolves (Canis lupus)

    International Nuclear Information System (INIS)

    Gjelsvik, Runhild; Holm, Elis; Kålås, John Atle; Persson, Bertil; Åsbrink, Jessica

    2014-01-01

    Wolves, lynx and wolverines are on the top of the food-chain in northern Scandinavia and Finland. 210 Po and 137 Cs have been analysed in samples of liver, kidney and muscle from 28 wolves from Sweden. In addition blood samples were taken from 27 wolves. In 9 of the wolves, samples of muscle, liver and blood were analysed for 210 Po. Samples of liver and muscle were collected from 16 lynx and 16 wolverines from Norway. The liver samples were analysed for 210 Po and 137 Cs. Only 137 Cs analyses were carried out for the muscle samples. The wolves were collected during the winter 2010 and 2011, while the samples for lynx and wolverines were all from 2011. The activity concentrations of 210 Po in wolves were higher for liver (range 20–523 Bq kg −1 d.w.) and kidney (range 24–942 Bq kg −1 d.w.) than muscle (range 1–43 Bq kg −1 d.w.) and blood (range 2–54 Bq kg −1 d.w.). Activity ratios, 210 Po/ 210 Pb, in wolf samples of muscle, liver and blood were in the ranges 2–77, 9–56 and 2–54. Using a wet weight ratio of 3.8 the maximal absorbed dose from 210 Po to wolf liver was estimated to 3500 μGy per year. Compared to wolf, the ranges of 210 Po in liver samples were lower in lynx (range 22–211 Bq kg −1 d.w.) and wolverine (range16–160 Bq kg −1 d.w.). Concentration of 137 Cs in wolf samples of muscle, liver, kidney and blood were in the ranges 70–8410 Bq kg −1 d.w., 36–4050 Bq kg −1 d.w., 31–3453 Bq kg −1 d.w. and 4–959 Bq kg −1 d.w., respectively. 137 Cs in lynx muscle and liver samples were in the ranges 44–13393 Bq kg −1 d.w. and 125–10260 Bq kg −1 d.w. The corresponding values for 137 Cs in wolverine were 22–3405 Bq kg −1 d.w. for liver and 53–4780 Bq kg −1 d.w. for muscle. The maximal absorbed dose from 137 Cs to lynx was estimated to 3000 μGy per year. - Highlights: • Annual doses from 210 Po are 1.4, 1.0 and 3.4 mGy for lynx, wolverine, and wolf. • Annual doses from 137 Cs are 3.3, 1.5 and 3.6 mGy for lynx, wolverine and wolf. • 210 Po/ 137 Cs ratios in wolf liver ranges from 0.01 to 4.0 and 0.002 to 0.05 in muscle. • The large spread in the data is due to the distribution of 137 Cs from Chernobyl. • The accumulation of 210 Po in liver and kidney is higher than for 137 Cs

  13. Contribution to the study of polonium-210 and lead-210 in marine organisms and their environment

    International Nuclear Information System (INIS)

    Heyraud, M.

    1982-06-01

    The following topics were emphasized: the role of 210 Po as a major source of natural radiation dose received by marin organisms; the contribution of 210 Po to the total α radioactivity in the hepatopancreas of crustaceans or mollusc cephalopods is more than 95%; in the euphausiid Meganyctiphanes norvegica, the main source of 210 Po is the food they consume; the possible use of 210 Po as a natural biological tracer of the feeding of deep-sea mesopelagic animals; the 210 Po/ 210 Pb ratio is a good indicator of the importance of biological processes in the marine environment [fr

  14. Trends in the chemical state of polonium-210 in the atmosphere

    International Nuclear Information System (INIS)

    Abe, M.; Abe, S.

    1980-01-01

    Trends of the chemial state of 210 Po in airborne dusts at Chiba, Japan, between 1963 and 1976 are discussed. A sublimination method is used to determine the chemical state of the 210 Po. The results show that the fraction of the component volatilizing at low temperature varies yearly in the range between 0 and 50%. If we assume the component comes from an artificial source, it may be suggested that a large fraction of 210 Po in airborne dusts comes from artificial sources. Additional reference data that show local properties of our sampling site are presented

  15. The polonium 210 in aerosols: contribution to the study of savannah fires and volcano emissions

    International Nuclear Information System (INIS)

    Nho-Kim, E.Y.

    1996-01-01

    Natural sources plan a fundamental role on the emission of the species causing climatic variations. The aim of this study is, on the one hand, to estimate fluxes of different components emitted by biomass burning and volcanoes, and on the other hand, to trace these components in time and space. We used 210 Po, last decay product in the 238 U series, as a tracer, as it is one of the characteristic species emitted by these sources: it is highly enriched in these plumes compared to the usual atmosphere and the 210 Po radioactivity is not affected by chemical transformation. We have shown that the contribution of biomass burning on the 210 Po concentration in local background atmosphere is minor during the dry season, compared to that of Saharan soil dusts despite of the importance of this source in the global budget of 210 Po (10%). However, the good correlation observed between the 210 Po concentration and that of carbonaceous aerosols and of CO 2 in biomass burning plumes reveals that 210 Po can be used as a reference of the components emitted by biomass burning. We have estimated the contribution of the Indonesian volcanoes which represent about 5 to 30 % of the global volcanic budget of trace metals. Atmospheric transport of these volcanic plumes was simulated using the 210 Po as a tracer. Due to the characteristic atmospheric circulation in this region, vertical transport is predominant over meridian dispersion, which is moderated by the convergence of the trade winds. The impact of these volcanic emissions on the atmospheric concentration of the trace metals remains a local effect when the volcanic activity is out of cataclysmal eruptions. (author)

  16. Metabolism and toxicity of polonium 210 and SiO2

    International Nuclear Information System (INIS)

    Panov, D.

    1978-02-01

    Synergistic effects of quartz dust and of Po-210 have been investigated in lungs and kidneys of rats. The substances (50mg silicone per animal, 5 (or 10)μCi of Po-210 per kg bodyweight) were introduced intratracheally in a single dose. Exposure times were 7 and 12 month. Postmortem the following quantities were determined: weight of lung and kidneys, Po-210 content, hydroxyproline contents of the lungs. Autoradiographic and histopathological investigations were carried out. It was found that synergistic effects increase mortallity. The most frequent cause of death was renal lesions. Po-210 behaves as a nephrotoxic agent, causing damages to all kidney structures, it mainly attacks the epithelium of convoluted renal tubules of nephrons. The cancerogenic effects of Po-210 are enhanced in the presens of quartz. Po-210 predominantly accumulates in the kidney cortex. Po content of lungs and kidneys was still high after 7 month. Po-retention was highest in kidneys not subjected to quartz, in lungs the opposite effect was observed. Hydroxyproline contents are moderately increased in Po-contaminated lungs

  17. The determination of polonium in urine of Filipino non-smokers and smokers

    International Nuclear Information System (INIS)

    Juan, N.B.; Ballelos, E.

    1976-03-01

    Po 210 , a decay product of Ra 226 , is a pure alpha emitter with an energy of 5.3 MeV decaying with a half-life of 138.4 days. It is a natural containment of tobacco and hence a health hazard to smokers. Previous study on Philippine cigarettes revealed that the average Po 210 activity of local brands is 0.0071 pCi/g. while that of foreign brands is 0.0129 pCi/g. Other studies indicate that approximately 0.13% of the total Po 210 in the body is excreted in the urine daily. Po urinalysis can serve as a rough index of the body burden of Po 210 and Ra 226 or anyone of its daughters absorbed in case of exposures. In this study, the Po 210 content in urine of smokers is compared with that of non-smokers. Twenty samples from non-smokers and twenty samples from smokers were analyzed for Po 210 activity. The average Po content of the urine of smokers, 0.2673+-0.1077 pCi/24h appears to be higher than the mean Po activity in urine of non-smokers, 0.1877+-0.1200. The t-value obtained from the comparison of the means was 2.205. This exceeds the t-value at the 0.05 significance level (degrees of freedom equal 19) which is 1.725. Therefore, there exists a significant difference in the Po content in the urine of non-smokers to that of smokers

  18. Gastrointestinal absorption and retention of polonium in adult and newborn rats and guinea pigs

    International Nuclear Information System (INIS)

    Haines, J.W.; Naylor, G.P.L.; Pottinger, H.; Harrison, J.D.

    1993-01-01

    The gastrointestinal absorption of 210 Po was determined by comparing tissue retention after oral and systemic administration. The results indicate an increase in absorption in adult rats for 210 Po administered in liver compared with 210 Po nitrate with estimated absorption of 5 and 13%, respectively. For 210 Po citrate, values of about 7% were obtained in 1-day-old neonate and adult rats while absorption in guinea pigs was estimated to be about 23% in 1-day-old neonates, 17% in 5-day-old neonates, and 9% in adults. Gut retention of ingested 210 Po in neonates was high in rats but not guinea pigs. In adult animals, but not neonates, the liver accounted for a greater proportion of 210 Po reaching the bloodstream after ingestion than after systemic injection. The significance of these results is discussed in relation to current assumptions made in the calculation of doses from 210 Po. (author)

  19. The human alimentary tract transfer and body retention of environmental polonium-210

    International Nuclear Information System (INIS)

    Hunt, G J; Rumney, H S

    2007-01-01

    This paper presents the results of a 4 year study to investigate the human alimentary tract transfer factor (f A value) and body retention of 210 Po in shellfish. In the first 3 years, mussels (Mytilus edulis L.), cockles (Cerastoderma edule L.) and brown meat from crab (Cancer pagurus L.) were successively studied. In each year five volunteers (from a pool of seven) ate a suitable portion of the shellfish and provided 24 h samples of excreta usually for 3 days before and for at least 7 days during and after eating. Subsamples of shellfish were analysed to determine the intakes of 210 Po. Faeces were analysed and the data used to assess apparent f A values. Urine samples were analysed in the mussel and crab studies to provide urinary excretion parameters. Pb-210 was also analysed during the mussel study; the levels were low, leading to large uncertainties, but confirming the negligible effect of radioactive decay to its granddaughter 210 Po in the main study. In the fourth year, larger samples of brown crab meat were eaten by five volunteers and faecal samples were taken at suitable times over periods of up to 43 days to study body retention of 210 Po. The first ∼7 days provided additional data on f A values. Pooled results for the apparent f A for the whole study lay in the range 0.15-0.65 with a mean of 0.46; corrections for endogenous excretion suggest a true f A value of ∼0.51, supporting the value of 0.5 currently used by the International Commission on Radiological Protection (ICRP). The retention data suggest a biological half-time of about 40 days, in broad consistency with the 50 days currently used by the ICRP. Thus there is no strong evidence from this study suggesting a change in dose coefficient for 210 Po. Full experimental data are provided to allow independent further interpretation

  20. Normal dietary levels of radium-226, radium-228, lead-210, and polonium-210 for man

    International Nuclear Information System (INIS)

    Holtzman, R.B.

    1980-01-01

    A review of the literature and the results of some recent measurements on the levels in man's diet of the naturally occurring radionuclides 226 Ra, 228 Ra, 210 Pb, and 210 Po are presented. Intakes in other countries are similar to those in the United States, but in localized populations the 226 Ra intake can be 8 or more pCi/day. The few data on 228 Ra show that intake of this nuclide is about 80% that of 226 Ra except in monazite areas where intakes of up to 160 pCi 228 Ra/day are reported. Drinking water contributes less than 5% to daily intake except in special areas. For 210 Pb, higher levels have been noted for Germany and the Union of Soviet Socialist Republics than for the United States. Persons in the Arctic who consume reindeer or caribou meat may ingest 210 Pb at the rate of 10 to 40 pCi/day. Normal dietary levels of 210 Po are about 20 to 30% higher than those of 210 Pb, except in the Arctic. The levels of these nuclides in classes of foods are compared to show that the higher levels observed in certain diets are due to the levels in particular foods. Because of the high levels of 210 Pb intake in Japan, total skeletal dose rates in that country are estimated to be more than twice those in the United States. The use of dietary intake for estimating metabolic parameters, such as intestinal absorption of 226 Ra and 210 Pb, is discussed

  1. Polonium-210 and lead-210 in the terrestrial environment: a historical review.

    Science.gov (United States)

    Persson, Bertil R R; Holm, Elis

    2011-05-01

    The radionuclides (210)Po and (210)Pb widely present in the terrestrial environment are the final long-lived radionuclides in the decay of (238)U in the earth's crust. Their presence in the atmosphere is due to the decay of (222)Rn diffusing from the ground. The range of activity concentrations in ground level air for (210)Po is 0.03-0.3 Bq m(-3) and for (210)Pb 0.2-1.5 Bq m(-3). In drinking water from private wells the activity concentration of (210)Po is in the order of 7-48 mBq l(-1) and for (210)Pb around 11-40 mBq l(-1). From water works, however, the activity concentration for both (210)Po and (210)Pb is only in the order of 3 mBq l(-1). Mosses, lichens and peat have a high efficiency in capturing (210)Po and (210)Pb from atmospheric fallout and exhibit an inventory of both (210)Po and (210)Pb in the order of 0.5-5 kBq m(-2) in mosses and in lichens around 0.6 kBq m(-2). The activity concentrations in lichens lies around 250 Bq kg(-1), dry mass. Reindeer and caribou graze lichen which results in an activity concentration of (210)Po and (210)Pb of about 1-15 Bq kg(-1) in meat from these animals. The food chain lichen-reindeer or caribou, and Man constitutes a unique model for studying the uptake and retention of (210)Po and (210)Pb in humans. The effective annual dose due to (210)Po and (210)Pb in people with high consumption of reindeer/caribou meat is estimated to be around 260 and 132 μSv a(-1) respectively. In soils, (210)Po is adsorbed to clay and organic colloids and the activity concentration varies with soil type and also correlates with the amount of atmospheric precipitation. The average activity concentration levels of (210)Po in various soils are in the range of 20-240 Bq kg(-1). Plants become contaminated with radioactive nuclides both by absorption from the soil (supported Po) and by deposition of radioactive fallout on the plants directly (unsupported Po). In fresh leafy plants the level of (210)Po is particularly high as the result of the direct deposition of (222)Rn daughters from atmospheric deposition. Tobacco is a terrestrial product with high activity concentrations of (210)Po and (210)Pb. The overall average activity concentration of (210)Po is 13 ± 2 Bq kg(-1). It is rather constant over time and by geographical origin. The average median daily dietary intakes of (210)Po and (210)Pb for the adult world population was estimated to 160 mBq day(-1) and 110 mBq day(-1), corresponding to annual effective doses of 70 μSv a(-1) and 28 μSv a(-1), respectively. The dietary intakes of (210)Po and (210)Pb from vegetarian food was estimated to only 70 mBq day(-1) and 40 mBq day(-1) corresponding to annual effective doses of 30.6 μSv a(-1) and 10 μSv a(-1), respectively. Since the activity concentration of (210)Po and (210)Pb in seafood is significantly higher than in vegetarian food the effective dose to populations consuming a lot of seafood might be 5-15 fold higher. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Radioecological modelling of Polonium-210 and Caesium-137 in lichen-reindeer-man and top predators.

    Science.gov (United States)

    Persson, Bertil R R; Gjelsvik, Runhild; Holm, Elis

    2018-06-01

    This work deals with analysis and modelling of the radionuclides 210 Pb and 210 Po in the food-chain lichen-reindeer-man in addition to 210 Po and 137 Cs in top predators. By using the methods of Partial Least Square Regression (PLSR) the atmospheric deposition of 210 Pb and 210 Po is predicted at the sample locations. Dynamic modelling of the activity concentration with differential equations is fitted to the sample data. Reindeer lichen consumption, gastrointestinal absorption, organ distribution and elimination is derived from information in the literature. Dynamic modelling of transfer of 210 Pb and 210 Po to reindeer meat, liver and bone from lichen consumption, fitted well with data from Sweden and Finland from 1966 to 1971. The activity concentration of 210 Pb in the skeleton in man is modelled by using the results of studying the kinetics of lead in skeleton and blood in lead-workers after end of occupational exposure. The result of modelling 210 Pb and 210 Po activity in skeleton matched well with concentrations of 210 Pb and 210 Po in teeth from reindeer-breeders and autopsy bone samples in Finland. The results of 210 Po and 137 Cs in different tissues of wolf, wolverine and lynx previously published, are analysed with multivariate data processing methods such as Principal Component Analysis PCA, and modelled with the method of Projection to Latent Structures, PLS, or Partial Least Square Regression PLSR. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. The ratio of lead-210 to polonium-210 in U.K. diet.

    Science.gov (United States)

    Smith-Briggs, J L; Bradley, E J; Potter, M D

    1986-10-01

    The levels of the natural radionuclides, 210Pb and 210Po, in U.K. diet have been measured previously. However, in the earlier measurements, the samples were sufficiently aged for 210Pb and 210Po to have attained secular equilibrium. In order to determine the extent of disequilibrium between these radionuclides in fresh food, measurements have been made on recently collected dietary samples. Disequilibrium has been observed in five food groups. The activity per unit mass of 210Pb was found to be greater than that of 210Po in bread, cereals, sugar and preserves, whereas the opposite was found to be true for eggs and beverages. When account is taken of consumption rates, however, the total intakes of 210Pb and 210Po from these food groups are approximately the same. The annual effective dose equivalents from the ingestion of 210Pb and 210Po have been re-estimated at 41 and 12 mu Sv, respectively.

  4. Polonium-210 and Caesium-137 in lynx (Lynx lynx), wolverine (Gulo gulo) and wolves (Canis lupus).

    Science.gov (United States)

    Gjelsvik, Runhild; Holm, Elis; Kålås, John Atle; Persson, Bertil; Asbrink, Jessica

    2014-12-01

    Wolves, lynx and wolverines are on the top of the food-chain in northern Scandinavia and Finland. (210)Po and (137)Cs have been analysed in samples of liver, kidney and muscle from 28 wolves from Sweden. In addition blood samples were taken from 27 wolves. In 9 of the wolves, samples of muscle, liver and blood were analysed for (210)Po. Samples of liver and muscle were collected from 16 lynx and 16 wolverines from Norway. The liver samples were analysed for (210)Po and (137)Cs. Only (137)Cs analyses were carried out for the muscle samples. The wolves were collected during the winter 2010 and 2011, while the samples for lynx and wolverines were all from 2011. The activity concentrations of (210)Po in wolves were higher for liver (range 20-523 Bq kg(-1) d.w.) and kidney (range 24-942 Bq kg(-1) d.w.) than muscle (range 1-43 Bq kg(-1) d.w.) and blood (range 2-54 Bq kg(-1) d.w.). Activity ratios, (210)Po/(210)Pb, in wolf samples of muscle, liver and blood were in the ranges 2-77, 9-56 and 2-54. Using a wet weight ratio of 3.8 the maximal absorbed dose from (210)Po to wolf liver was estimated to 3500 μGy per year. Compared to wolf, the ranges of (210)Po in liver samples were lower in lynx (range 22-211 Bq kg(-1) d.w.) and wolverine (range16-160 Bq kg(-1) d.w.). Concentration of (137)Cs in wolf samples of muscle, liver, kidney and blood were in the ranges 70-8410 Bq kg(-1) d.w., 36-4050 Bq kg(-1) d.w., 31-3453 Bq kg(-1) d.w. and 4-959 Bq kg(-1) d.w., respectively. (137)Cs in lynx muscle and liver samples were in the ranges 44-13393 Bq kg(-1) d.w. and 125-10260 Bq kg(-1) d.w. The corresponding values for (137)Cs in wolverine were 22-3405 Bq kg(-1) d.w. for liver and 53-4780 Bq kg(-1) d.w. for muscle. The maximal absorbed dose from (137)Cs to lynx was estimated to 3000 μGy per year. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Analysis of polonium-210 in food products and bioassay samples by isotope-dilution alpha spectrometry

    International Nuclear Information System (INIS)

    Lin Zhichao; Wu Zhongyu

    2009-01-01

    A rapid and reliable radiochemical method coupled with a simple and compact plating apparatus was developed, validated, and applied for the analysis of 210 Po in variety of food products and bioassay samples. The method performance characteristics, including accuracy, precision, robustness, and specificity, were evaluated along with a detailed measurement uncertainty analysis. With high Po recovery, improved energy resolution, and effective removal of interfering elements by chromatographic extraction, the overall method accuracy was determined to be better than 5% with measurement precision of 10%, at 95% confidence level.

  6. Analysis of polonium-210 in food products and bioassay samples by isotope-dilution alpha spectrometry.

    Science.gov (United States)

    Lin, Zhichao; Wu, Zhongyu

    2009-05-01

    A rapid and reliable radiochemical method coupled with a simple and compact plating apparatus was developed, validated, and applied for the analysis of (210)Po in variety of food products and bioassay samples. The method performance characteristics, including accuracy, precision, robustness, and specificity, were evaluated along with a detailed measurement uncertainty analysis. With high Po recovery, improved energy resolution, and effective removal of interfering elements by chromatographic extraction, the overall method accuracy was determined to be better than 5% with measurement precision of 10%, at 95% confidence level.

  7. Polonium-210 and lead-210 in marine organisms: allometric relationships and their significance

    International Nuclear Information System (INIS)

    Cherry, R.D.; Heyraud, M.

    1991-01-01

    Allometric relationships which indicate that Po-210 concentrations in marine organisms decrease with increasing organism mass have been reported previously in a few taxa. We report here the results of a study of nearly 400 data covering nine taxa of marine organisms. The data for each taxon are fitted to the allometric equation log Q = log a + b log M, where Q is the Po-210 concentration (mBq/g dry mass) and M is the dry mass per individual (g). The weighted mean of the nine Po-210 slopes is -0.24 ± 0.05, and of the eight Pb-210 slopes is -0.22 ± 0.05. These values are close to the slope of -0.25 frequently found in mass-specific allometric relationships in biology; an association between radionuclide concentration and food ingestion rate is indicated. The intertaxon variations in the intercept log a are large, nearly two orders of magnitude for Po-210, a fact which almost certainly reflects intertaxon differences in diet and/or assimilation. Within taxa, sub-groupings of the Po-210 data are found; these are discussed and an attempt is made to classify them statistically for the data as a whole. (Author)

  8. Polonium-210 and radiocaesium in muscle tissue of fish from different Nordic marine areas

    International Nuclear Information System (INIS)

    Holm, E.

    1994-01-01

    210 Po and radiocaesium were analyzed in the muscle tissue of different species of fish from the Baltic Sea, the Norwegian Sea and Icelandic waters. On the basis of the results a dose assessment was made which demonstrates that the dose to the population from 210 Po originating from the consumption of fish from the Baltic Sea is similar so that from radiocaesium, even after the Chernobyl accident. For the other areas the dose from radiocaesium is smaller but of the same importance as that from 210 Po. Differences in salinity are of minor importance compared to the food chains with respect to 210 Po. (orig.)

  9. Polonium-210 and Lead-210 in marine biota from a coastal region with high natural radioactivity

    International Nuclear Information System (INIS)

    Zafrul Kabir, M.; Deeba, Farah; Hossain, Sushmita; Fharim, Massoud; Md Moniruzzaman; Carvalho, Fernando P.; Oliveira, João M.; Malta, M.; Silva, L.

    2013-01-01

    Coastal sediments and marine fish from a region with high natural radioactivity in Cox Bazar Bangladesh, were analyzed in order to investigate the levels of naturally occurring radionuclides. Sediment from the sea shore in high ambient radiation dose rate areas contained naturally occurring radionuclides at high concentrations. These sediments displayed 226 Ra, 232 Th and 235 U activity concentrations of 2184 ± 88 Bq kg -1 dry weight (d.w.), 3808 ± 200 Bq kg -1 (d.w.) and 123 ± 15 Bq kg -1 (d.w.), respectively. In contrast with these high values, radionuclide concentrations in sand from other areas of the Cox's Bazar coast were as low as 42 ± 3, 70 ± 4 and < 8 Bq kg -1 (d.w.) for the same radionuclides, respectively, which are comparable to concentrations determined in many coastal areas elsewhere. The presence of sand deposits with high concentration of uranium series radionuclides could potentially originate high accumulation of alpha emitting radionuclides such as 210 Po in marine biota, and food chain transfer to man. 210 Po is a major contributor to the radiation dose both in marine organisms and sea food consumers. Determination of 210 Po in marine fish and shrimp from the area lead to concentration values ranging from 4.5±0.3 to 124±3 Bq kg -1 (d.w.) in fish and 82.9±1.6 Bq kg -1 (d.w.) in shrimp. Similar concentrations are commonly reported in marine biota from several regions. Therefore, in spite of the deposits of heavy mineral sands containing high concentrations of radionuclides such as 210 Pb and 210 Po no significant raise in the accumulation of these radionuclides in biota seems to occur, which suggests that radionuclides are tightly bound in sediment grains and are not significantly bioavailable. (author)

  10. Polonium-210 concentration in the hair of 51 radium dial painters

    Energy Technology Data Exchange (ETDEWEB)

    Erkang, Zeng; Nanxiang, Li

    1984-07-01

    The /sup 210/Po concentration in the hair of 51 radium dial painters (one group of 29 male, and the another group of 22 female) was reported in this paper. It was found that the /sup 210/Po concentration in the hair of both the male and female painters were significantly higher than that of the controls. A correlation has also been observed between the /sup 210/Po concentration in the hair and the working ages of the male painters.

  11. Polonium-210 and lead-210 in the terrestrial environment: a historical review

    International Nuclear Information System (INIS)

    Persson, Bertil R.R.; Holm, Elis

    2011-01-01

    The radionuclides 210 Po and 210 Pb widely present in the terrestrial environment are the final long-lived radionuclides in the decay of 238 U in the earth's crust. Their presence in the atmosphere is due to the decay of 222 Rn diffusing from the ground. The range of activity concentrations in ground level air for 210 Po is 0.03-0.3 Bq m -3 and for 210 Pb 0.2-1.5 Bq m -3 . In drinking water from private wells the activity concentration of 210 Po is in the order of 7-48 mBq l -1 and for 210 Pb around 11-40 mBq l -1 . From water works, however, the activity concentration for both 210 Po and 210 Pb is only in the order of 3 mBq l -1 . Mosses, lichens and peat have a high efficiency in capturing 210 Po and 210 Pb from atmospheric fallout and exhibit an inventory of both 210 Po and 210 Pb in the order of 0.5-5 kBq m -2 in mosses and in lichens around 0.6 kBq m -2 . The activity concentrations in lichens lies around 250 Bq kg -1 , dry mass. Reindeer and caribou graze lichen which results in an activity concentration of 210 Po and 210 Pb of about 1-15 Bq kg -1 in meat from these animals. The food chain lichen-reindeer or caribou, and Man constitutes a unique model for studying the uptake and retention of 210 Po and 210 Pb in humans. The effective annual dose due to 210 Po and 210 Pb in people with high consumption of reindeer/caribou meat is estimated to be around 260 and 132 μSv a -1 respectively. In soils, 210 Po is adsorbed to clay and organic colloids and the activity concentration varies with soil type and also correlates with the amount of atmospheric precipitation. The average activity concentration levels of 210 Po in various soils are in the range of 20-240 Bq kg -1 . Plants become contaminated with radioactive nuclides both by absorption from the soil (supported Po) and by deposition of radioactive fallout on the plants directly (unsupported Po). In fresh leafy plants the level of 210 Po is particularly high as the result of the direct deposition of 222 Rn daughters from atmospheric deposition. Tobacco is a terrestrial product with high activity concentrations of 210 Po and 210 Pb. The overall average activity concentration of 210 Po is 13 ± 2 Bq kg -1 . It is rather constant over time and by geographical origin. The average median daily dietary intakes of 210 Po and 210 Pb for the adult world population was estimated to 160 mBq day -1 and 110 mBq day -1 , corresponding to annual effective doses of 70 μSv a -1 and 28 μSv a -1 , respectively. The dietary intakes of 210 Po and 210 Pb from vegetarian food was estimated to only 70 mBq day -1 and 40 mBq day -1 corresponding to annual effective doses of 30.6 μSv a -1 and 10 μSv a -1 , respectively. Since the activity concentration of 210 Po and 210 Pb in seafood is significantly higher than in vegetarian food the effective dose to populations consuming a lot of seafood might be 5-15 fold higher.

  12. Distribution and intake of polonium-210 in the environment of Goa

    International Nuclear Information System (INIS)

    Avadhani, D.N.; Mahesh, H.M.; Narayana, Y.; Siddappa, K.; Karunakara, N.; Somashekarappa, H.M.

    1999-01-01

    The paper deals with the distribution of 210 Po in soil, sand and food samples of the Goa region. The activity concentration of 210 Po in diet samples of the region were also measured and the annual effective internal dose due to ingestion of this radionuclide was estimated. The activity of 210 Po in soil and sand samples vary from 9.8 Bq kg -1 to 43.2 Bq kg -1 with a mean value of 26.3 Bq kg -1 and from 0.94 Bq kg -1 to 3.67 Bq kg -1 with the mean value of 1.82 Bq kg -1 respectively. Among food samples fish and prawn shows higher concentration of 210 Po. The committed effective dose equivalent due to veg and non-veg meals were found to be 13.49 μSvy -1 and 24.83 μSvy -1 respectively which is well below the dose limit of 1 mSvy -1 recommended by ICRP. (author)

  13. Polonium-210 in seaweeds of the Krusadai island, Gulf of Mannar

    International Nuclear Information System (INIS)

    Somasundaram, S.S.N.; Shaheed, K.; Shahul Hameed, P.

    1997-01-01

    The concentration of 210 Po, an alpha emitter of the natural uranium series was measured in some commercial seaweeds, collected from Krusadai island, the south east coast of Tamil Nadu. The concentration of 210 Po in water and sediment samples was found to be 2.80 mBq/l and 36.2 Bq/kg respectively. The 210 Po was observed to be non-uniformly distributed among the seaweeds, which maintained the following descending order: Ulva reticulata (30.0 Bq/kg > Cystophyllum murictum (24.9 Bq/kg) > Sargassum wightti (22.1 Bq/kg) > Sargassum ilicifolium (19.6 Bq/kg) > Hypnea valentiae (15.09 Bq/kg) > Gracilaria follifera (14.87 Bq/kg) > Gracilaria edulis (10.12 Bq/kg) > Turbinaria conoides (8.5 Bq/kg) > Gelidiella acerosa (5.80 Bq/kg). The general range of CF s for the macro algae varies between 10 3 and 10 4 . The distribution of 210 Po in the seaweeds and its relation to the protein content is discussed. (author). 14 refs., 2 figs., 1 tab

  14. Polonium-210 in marine bivalves inhabiting a wedge bank region, South India

    International Nuclear Information System (INIS)

    Feroz Khan, M.; Godwin Wesley, S.; Rajan, M.P.

    2013-01-01

    Determination of background radiation dose-rate is important in the process of assessing risks to the environment from exposure to living organisms both in terms of deriving the incremental dose-rate and as a point of reference for evaluating the significance of the exposure level. In the present study, 210 Po was quantified in two species of bivalve mollusks commonly available from so called a 'wedge bank region' of southern tip of India. Based on the activity concentration in media and in the whole body, an external and internal dose rate assessment to green mussel Perna viridis and brown mussel Perna indica due to 210 Po was derived using ERICA assessment tool. The samples were collected at the intertidal region along the wedge bank region of southern tip of India during 2009 to 2010. The measurement contributes to a better knowledge of these elements, since no data exists in this region. 5-10 g of each tissue sample was wet-digested using 70% concentrated HNO 3 followed by the addition of 40% H 2 O 2 along with 20 8Po tracer (0.2 Bq). The normality of the data set was checked using Lilliefors test (ne''50) and potential outliers, if any, were tested using Walsh's test (n>60). Using the measured 210 Po activity in molluscs, sediments and seawater, dose assessment was performed using the Tier 2 ERICA environment dose assessment tool 1.0

  15. 210Polonium and 210lead content of marine birds from Southeastern Brazil

    International Nuclear Information System (INIS)

    Godoy, José Marcus; Siciliano, Salvatore; Carvalho, Zenildo Lara de; Tavares, Davi C.; Fulgencio de Moura, Jaílson

    2014-01-01

    In this study, we report the 210 Po and 210 Pb concentrations of bone, muscle and liver samples that were obtained from twelve different marine bird species stranded on beaches in the central–north region of Rio de Janeiro State. Both radionuclides were highly concentrated in the liver samples; however, the lowest mean 210 Po/ 210 Pb activity ratio (1.3) was observed in bones compared with liver and muscle (16.8 and 13.8, respectively). Among the species that were studied, Fregata magnificens, with a diet based exclusively on fish, had the lowest 210 Pb and 210 Po concentrations and the lowest 210 Po/ 210 Pb activity ratio. The 210 Po concentrations in Puffinus spp. liver samples followed a log-normal distribution, with a geometric mean of 300 Bq kg -1 wet weight . Only two references pertaining to 210 Po in marine birds were found in a Web of Science search of the literature, and each study reported a different concentration value. The values determined in this experiment are consistent with those in one of the previous studies, which also included one of the species studied in this work. No values for 210 Pb in marine birds have been published previously. - Highlights: • 210 Po and 210 Pb were determined in muscle, liver and bone samples of marine birds. • For both radionuclides, the highest concentrations were observed on liver samples. • Only three previous publications on 210 Po in marine birds were found in the literature. • The obtained results represent the first one related to 210 Pb in marine birds

  16. Distribution of lead-210 and polonium-210 between soluble and particulate phases in seawater

    International Nuclear Information System (INIS)

    Spencer, D.W.

    1975-01-01

    Results are reported from radiometric measurements of the distribution of 210 Pb and 210 Po in surface seawater and suspended particulate matter. Samples of plankton and sediments collected from some locations were also analyzed. Samples of seawater and suspended particulate matter were collected from stations located in the Gulf of Maine, the North Atlantic, and approximately 500 miles southwest of Gilbraltar. (U.S.)

  17. Polonium-210 assay using a background-rejecting extractive liquid-scintillation method

    International Nuclear Information System (INIS)

    Case, C.N.; McDowell, W.J.

    1981-01-01

    This paper describes a procedure which combines solvent extraction with alpha liquid scintillation spectrometry. Pulse shape discrimination electronics are used to reject beta and gamma pulses and to lower the background count to acceptable levels. Concentration of 210 Po and separation from interferring elements are accomplished using a H 3 Po 4 -HCl solution with TOPO combined with a scintillor in toluene

  18. Isotopically tailored lead target with reduced polonium and bismuth radio-waste

    International Nuclear Information System (INIS)

    Khorasanov, G.L.; Ivanov, A.P.; Lunev, V.P.; Blokhin, A.I.

    2002-01-01

    Residual activity of a lead target after 1 year irradiation with a high power, 0.8 GeV*30 mA, proton beam is studied. It is concluded that the main radiotoxicity of irradiated lead is connected with bismuth isotope, Bi-207, which is produced in natural lead, mix of several stable isotopes, via (p,2n) reaction with Pb-208 nuclei. It is proposed to use, as a target material, lead enriched with another stable isotope, Pb-206, in order to reduce producing Bi-207 and Po-210. Estimation of charges for obtaining large quantities of lead-206 is also given. Accumulation of hazardous radionuclides, Bi-207, Bi-208, and Po-210, in natural lead to be used as a coolant in future fast reactors and accelerator driven reactors is predicted. In accelerator driven systems a large portion of Bi-207 can be produced via Pb-208(p,2n)Bi-207 reaction in a target of natural lead (Pb-208/Pb-207/Pb-206/Pb-204=52.35/22.08/24.14/1.42 %). A new isotopically tailored coolant-converter for ADS consisting of lead isotope, Pb-206, is proposed. By using this material, it is possible to reduce essentially the production of the most radio-toxic isotopes of Bi and Po and to avoid disposing the large amounts of lead. To provide the future fast reactors and accelerator driven systems with low-activation coolant - converter, the new technology of obtaining the large amounts of natural lead enriched with lead isotope, Pb-206, should be developed. (authors)

  19. Decay of mass-separated 3.0min 195gBi to levels in 195Pb and shape coexistence in the neutron-deficient odd-mass Pb isotopes

    International Nuclear Information System (INIS)

    Griffin, J.C.; Braga, R.A.; Fink, R.W.; Bingham, C.R.; Coenen, E.; Huyse, M.; Duppen, P. van

    1991-01-01

    The radioactive decay of mass-separated 3.0 m 195g Bi to 195 Pb has been studied with the UNISOR and LISOL facilities. Time-sequenced spectra of γ-rays, X-rays, and conversion electrons have been obtained, together with γγt, γXt, eγt, and eXt coincidence data. From this information, a decay scheme has been constructed consisting of 23 excited states and 34 transitions in 195 Pb. Transitions with E0 multipole admixtures, indicative of shape coexistence, have been found to de-excite positive-parity levels at 1093, 1329, and 1380 keV. The beta-decay energy of the 195 Bi ground state is deduced to be Q EC =4800 +600 -550 keV based on the measurement of γ-ray-gated K/β + ratios. The excitation energy of the i 13/2 isomer in 195 Pb has been determined to be 203±4 keV from the α-decays of 199m,g Po. (orig.)

  20. The polonium 210 in aerosols: contribution to the study of savannah fires and volcano emissions; Le polonium 210 dans les aerosols: contribution a l`etude des feux de savanes et des emissions volcaniques

    Energy Technology Data Exchange (ETDEWEB)

    Nho-Kim, E.Y

    1996-06-27

    Natural sources plan a fundamental role on the emission of the species causing climatic variations. The aim of this study is, on the one hand, to estimate fluxes of different components emitted by biomass burning and volcanoes, and on the other hand, to trace these components in time and space. We used {sup 210}Po, last decay product in the {sup 238}U series, as a tracer, as it is one of the characteristic species emitted by these sources: it is highly enriched in these plumes compared to the usual atmosphere and the {sup 210}Po radioactivity is not affected by chemical transformation. We have shown that the contribution of biomass burning on the {sup 210}Po concentration in local background atmosphere is minor during the dry season, compared to that of Saharan soil dusts despite of the importance of this source in the global budget of {sup 210}Po (10%). However, the good correlation observed between the {sup 210}Po concentration and that of carbonaceous aerosols and of CO{sub 2} in biomass burning plumes reveals that {sup 210}Po can be used as a reference of the components emitted by biomass burning. We have estimated the contribution of the Indonesian volcanoes which represent about 5 to 30 % of the global volcanic budget of trace metals. Atmospheric transport of these volcanic plumes was simulated using the {sup 210}Po as a tracer. Due to the characteristic atmospheric circulation in this region, vertical transport is predominant over meridian dispersion, which is moderated by the convergence of the trade winds. The impact of these volcanic emissions on the atmospheric concentration of the trace metals remains a local effect when the volcanic activity is out of cataclysmal eruptions. (author)

  1. Lead-210 and polonium-210 as marine geochemical tracers: review and discussion of results from the Laborador Sea

    International Nuclear Information System (INIS)

    Bacon, M.P.; Spencer, D.W.; Brewer, P.G.

    1980-01-01

    Because of their suitable half-lives and their accurately measurable rates of supply to the oceans by decay of parent radionuclides, 210 Pb and 210 Po have become increasingly important as tracers in the study of marine geochemical processes. Short removal times characterize the behavior of both nuclides in the biologically productive surface layers of the sea. Release from particles at depth is efficient for 210 Po but does not appear to be significant for 210 Pb. Scavenging processes in the deep sea are revealed by 210 Pb/ 226 Ra and 210 Po/ 210 Pb disequilibriums. Adsorption by particles sinking in the water column and reaction at the seafloor both appear to be important removal mechanisms. Results from four stations in the Labrador Sea are shown to be consistent with many earlier observations. Significant 210 Pb depletions, however, are found only at depths greater than 1500 m. Below 1500 m, 210 Pb/ 226 Ra ratios decrease steadily with depth to very low values in the Iceland-Scotland Overflow and Denmark Straits Overflow waters. The intense interaction of these water masses with the seafloor may account for this trend

  2. Size distribution and origin of lead-210, bismuth-210, and polonium-210 on airborne particles in the troposphere

    International Nuclear Information System (INIS)

    Moore, H.E.; Poet, S.E.; Martell, E.A.

    1980-01-01

    Data are presented on the concentration, specific activity and percent of 210 Pb, 210 Bi, and 210 Po vs particle size interval for ground level air samples. Similar data for 90 Sr in air and 226 Ra and 210 Pb in one soil sample are given. Calculated mean aerosol residence times increase with increasing particle size interval; however, specific activities and percent of each isotope decrease with increasing particle size interval. These variations, along with comparision to soil data, suggest that the distribution of these isotopes reflects the initial attachment distribution plus a smaller component due to entrainment of particles from soil and other surfaces

  3. Lead-210, bismuth-210, polonium-210. Natural activity, internal dosimetry, and dose factors for ingestion and inhalation

    International Nuclear Information System (INIS)

    Jacobi, W.

    1979-02-01

    Starting with a comprehensive review of the normal, natural activity of 210 Pb and 210 Po in the environment and in the tissues of the human body, a model of the activity and dose distributions of this nuclides in the human body is developed. Dose factors for ingestion with food and for inhalation are derived from this model, related to the intake rate unit. This 'natural exposure model' can be used for an estimation of the population exposure due to normal natural radiation as well as to man-made sourcess of these nuclides, e.g. coal-fired power plants. (orig.) [de

  4. Improving the Selectivity of the ISOLDE Resonance Ionization Laser Ion Source and In-Source Laser Spectroscopy of Polonium

    CERN Document Server

    Fink, Daniel Andreas; Jochim, Selim

    Exotic atomic nuclei far away from stability are fascinating objects to be studied in many scientic elds such as atomic-, nuclear-, and astrophysics. Since these are often short-lived isotopes, it is necessary to couple their production with immediate extraction and delivery to an experiment. This is the purpose of the on-line isotope separator facility, ISOLDE, at CERN. An essential aspect of this laboratory is the Resonance Ionization Laser Ion Source (RILIS) because it provides a fast and highly selective means of ionizing the reaction products. This technique is also a sensitive laser-spectroscopy tool for the development and improvement of electron excitation schemes for the resonant laser photoionization and the study of the nuclear structure or fundamental atomic physics. Each of these aspects of the RILIS applications are subjects of this thesis work: a new device for the suppression of unwanted surface ionized contaminants in RILIS ion beams, known as the Laser Ion Source and Trap (LIST), was impleme...

  5. Measurement of natural radioactivity for polonium-210 in water and soil samples from Vythiry Taluk, Wayanad district, Kerala

    International Nuclear Information System (INIS)

    Athif, P.; Periyasamy, M.; Syed Mohamed, H.E.; Sadiq Bukhari, A.; Shajeer, P.A.; Kogilan, R.; Muzammil, F.S.

    2017-01-01

    Ground water and soil samples were collected from various tea plantation regions of the Vythiry taluk, Wayanad district, Kerala and measured the "2"1"0Po activity concentration. The descriptive statistical analysis was carried out using SPSS version 16. The higher distribution is observed between water and soil (1.8 mBq/L and 2.8 Bq/Kg) respectively. (author)

  6. Polonium ({sup 210}Po) and lead ({sup 210}Pb) in marine organisms and their transfer in marine food chains

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fernando P., E-mail: carvalho@itn.p [Instituto Tecnologico e Nuclear, Departamento de Proteccao Radiologica e Seguranca Nuclear, E.N. 10, 2686-953 Sacavem (Portugal)

    2011-05-15

    The determination of {sup 210}Po and {sup 210}Pb was performed in marine organisms from the seashore to abyssal depths, encompassing a plethora of species from the microscopic plankton to the sperm whale. Concentrations of those radionuclides ranged from low values of about 5 x 10{sup -1} Bq kg{sup -1} (wet wt.) in jellyfish, to very high values of about of 3 x 10{sup 4} Bq kg{sup -1} (wet wt.) in the gut walls of sardines, with a common pattern of {sup 210}Po > {sup 210}Pb.These radionuclides are primarily absorbed from water and concentrated by phyto- and microzooplankton, and then are transferred to the next trophic level along marine food chains. Investigation in epipelagic, mesopelagic, bathypelagic and abyssobenthic organisms revealed that {sup 210}Po is transferred in the marine food webs with transfer factors ranging from 0.1 to 0.7, and numerically similar to those of the energy transfer in the marine food chains. As {sup 210}Po preferentially binds to amino acids and proteins, its transfer in food chains likely traces protein transfer and, thus, {sup 210}Po transfer factors are similar to ecotrophic coefficients. {sup 210}Pb is transferred less efficiently in marine food chains and this contributes to increased {sup 210}Po:{sup 210}Pb activity ratios in some trophic levels.

  7. Internal radiation dose to the public from polonium-210 due to consumption of seafood from Bombay-harbour bay

    International Nuclear Information System (INIS)

    Bangera, V.S.; Rudran, Kamala

    1995-01-01

    Marine organisms such as fishes, molluscs and crustaceans are known to accumulate 210 Po. Distribution of 210 Po in coastal marine organisms mainly fishes and shell fishes is studied. Concentration of 210 Po obtained in muscle of common fishes (edible portion) varied from 2.10 ± 0.11 to 21.90 ± 5.00 Bq kg -1 dry muscle (for fishes like Pampus argenteus (Pomfret), Cynoglossus elongatus (sole), Rastrelliger kanagurta (mackerel), Harpodon nehereus (Bombay duck) etc. Concentration factors for 210 Po in edible portion of fish from sea water works out to 10 3 to 10 4 . Radiation dose to the public has been evaluated on the basis of daily intake of 40 g of fish (15 kg y -1 ). Committed effective dose (CED) to 210 Po due to consumption of sea food is calculated, CED varied from 2.05 x 10 -3 to 4 x 10 -2 mSv y -1 . (author). 7 refs., 3 figs., 3 tabs

  8. Polonium (210Po) and lead (210Pb) in marine organisms and their transfer in marine food chains.

    Science.gov (United States)

    Carvalho, Fernando P

    2011-05-01

    The determination of (210)Po and (210)Pb was performed in marine organisms from the seashore to abyssal depths, encompassing a plethora of species from the microscopic plankton to the sperm whale. Concentrations of those radionuclides ranged from low values of about 5 × 10(-1) Bq kg(-1) (wet wt.) in jellyfish, to very high values of about of 3 × 10(4) Bq kg(-1) (wet wt.) in the gut walls of sardines, with a common pattern of (210)Po > (210)Pb.These radionuclides are primarily absorbed from water and concentrated by phyto- and microzooplankton, and then are transferred to the next trophic level along marine food chains. Investigation in epipelagic, mesopelagic, bathypelagic and abyssobenthic organisms revealed that (210)Po is transferred in the marine food webs with transfer factors ranging from 0.1 to 0.7, and numerically similar to those of the energy transfer in the marine food chains. As (210)Po preferentially binds to amino acids and proteins, its transfer in food chains likely traces protein transfer and, thus, (210)Po transfer factors are similar to ecotrophic coefficients. (210)Pb is transferred less efficiently in marine food chains and this contributes to increased (210)Po:(210)Pb activity ratios in some trophic levels. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. 210-Polonium studies in some environmental and biological matrices of Domiasiat uranium deposit area, West Khasi Hills, Meghalaya, India.

    Science.gov (United States)

    Marbaniang, Deswyn G; Poddar, Raj K; Nongkynrih, Phlis; Khathing, Darlando T

    2010-03-01

    The study was performed using a silicon surface barrier alpha spectrometer at Bhabha Atomic Research Centre, Mumbai, India. Through the study, the observed (210)Po activity in water sample from different locations in the Domiasiat area ranges from 0.04 to 0.69 Bq/l. The daily and annual intake of (210)Po through water was also estimated and the mean value of 0.72 and 263.61 Bq, respectively, were observed. It is observed that the effective doses through water were higher than the World Health Organization recommended dose of 0.05 mSv/year. The total annual effective doses through terrestrial ingestion for all the locations was studied and the mean annual effective dose was observed to be 0.315 mSv, which, when compared to the worldwide and the Indian values, was observed to be slightly higher. The mean activity in soil is found to be 124.8 +/-5.7 Bq/kg and in meat the activity is 0.43 +/-0.05 Bq/kg. In fishes, an activity of 0.48 +/-0.07 Bq/kg in Garra lamta, 0.29 +/-0.02 Bq/kg in Neolissocheilus hexaganolepis, and 3.3 +/-0.1 Bq/kg in Macrobrachium sp. is observed. Activity concentration in plant samples was analyzed and the activity ranges from 0.020 +/-0.002 to 9.69 +/-0.35 Bq/kg. Committed effective dose by the adult population of the Domiasiat area through intake of (210)Po through these food items was also determined and compared with the Indian average value and the worldwide average value.

  10. Polonium-210 and Lead-210 in food and tobacco products: transfer parameters and normal exposure and dose

    International Nuclear Information System (INIS)

    Watson, A.P.

    1985-01-01

    Food-chain transport of Pb-210 and Po-210 from soil to edible plant parts and from animal feed to meat and milk was evaluated from a review of literature. The degree of transfer was characterized by estimating concentration factors as well as the transfer coefficients B/sub v/, B/sub r/, f/sub m/, and f/sub f/. Global dietary intake of Pb-210 and Po-210 was also summarized, and 50-y dose estimates to target organs were calculated. The greatest estimated ingestion doses were those to populations with large dietary complements of animal protein in the form of seafood (Japan) or caribou/reindeer muscle and organ meats (Arctic Eskimos and Lapps). The origin and magnitude of inhalation exposure and dose from tobacco products were also assessed. For the majority of internal organs evaluated, the dose resulting from smoking commercially available tobacco products is comparable with or greater than the dose estimates for ingestion of naturally occurring dietary Pb-210 and Po-210. 79 refs

  11. Polonium (210Po) and lead (210Pb) in marine organisms and their transfer in marine food chains

    International Nuclear Information System (INIS)

    Carvalho, Fernando P.

    2011-01-01

    The determination of 210 Po and 210 Pb was performed in marine organisms from the seashore to abyssal depths, encompassing a plethora of species from the microscopic plankton to the sperm whale. Concentrations of those radionuclides ranged from low values of about 5 x 10 -1 Bq kg -1 (wet wt.) in jellyfish, to very high values of about of 3 x 10 4 Bq kg -1 (wet wt.) in the gut walls of sardines, with a common pattern of 210 Po > 210 Pb.These radionuclides are primarily absorbed from water and concentrated by phyto- and microzooplankton, and then are transferred to the next trophic level along marine food chains. Investigation in epipelagic, mesopelagic, bathypelagic and abyssobenthic organisms revealed that 210 Po is transferred in the marine food webs with transfer factors ranging from 0.1 to 0.7, and numerically similar to those of the energy transfer in the marine food chains. As 210 Po preferentially binds to amino acids and proteins, its transfer in food chains likely traces protein transfer and, thus, 210 Po transfer factors are similar to ecotrophic coefficients. 210 Pb is transferred less efficiently in marine food chains and this contributes to increased 210 Po: 210 Pb activity ratios in some trophic levels.

  12. The structure of nuclei far from beta stability: A progress report for the period May 15, 1987 to May 14, 1988

    International Nuclear Information System (INIS)

    Zganjar, E.F.

    1988-01-01

    The research at UNISOR constitues the major effort of our work on far from stability nuclei. The extensive data from the UNISOR studies on the neutron-deficient Tl Hg, Au and Pt isotopes has not only established a new region of nuclear deformation and a new class of nuclear structure at closed shells; but, after full analysis, will ultimately transform our present understanding of shape coexistence. Our experimental approach is to take great care to obtain accurate experimental information and then to take equally great care in its interpretation. We have shown in the study of the odd-A Au isotopes that one can use the odd proton to probe the even-even Pt cores and thus expose the finer details of the coexisting structures in those cores. We have also shown that to utilize such an approach one must systematically track all states below about 1 MeV across isotopic or isotonic sequences; and that to accomplish such a tracking it is necessary to push the spectroscopic measurements to new limits in terms of quality and statistics. The major results of the recent work involve the developemnt of a unified description of intruder states and shape coexistence in nuclei

  13. A systematic study of superheavy nuclei for Z = 114 and beyond using the relativistic mean field approach

    International Nuclear Information System (INIS)

    Patra, S.K.; Wu, Cheng-Li; Praharaj, C.R.; Gupta, Raj K.

    1999-01-01

    We have studied the structural properties of even-even, neutron deficient, Z=114-126, superheavy nuclei in the mass region A ∼ 270-320, using an axially deformed relativistic mean field model. The calculations are performed with three parameter sets (NL1, TM1 and NL-SH), in order to see the dependence of the structural properties on the force used. The calculated ground state shapes are found to be parameter dependent. For some parameter sets, many of the nuclei are degenerate in their ground state configuration. Special attention is given to the investigation of the magic structures (spherical shell closures) in the superheavy region. We find that some known magic numbers are absent and new closed shells are predicted. Large shell gaps appear at Z=80, 92, (114), 120 and 138, N=138, (164), (172), 184, (198), (228) and 258, irrespective of the parameter sets used. The numbers in parenthesis are those which correspond to relatively smaller gaps. The existence of new magic numbers in the valley of superheavy elements is discussed. It is suggested that nuclei around Z=114 and N = 164 ∼ 172 could be considered as candidates for the next search of superheavy nuclei. The existence of superheavy islands around Z=120 and N=172 or N 184 double shell closure is also discussed

  14. A study on the distribution of alpha emitting radionuclides Polonium-210 in the Pitchavaram mangrove forest, southeast coast of India (Bay of Bengal)

    International Nuclear Information System (INIS)

    Raja, P.; Sadiq Bukhari, A.; Krishnamoorthy, R.; Shahul Hameed, M.M.; Shahul Hameed, P.

    2004-01-01

    The environmental samples such as water, sediment and biota (prawns, crabs, bivalves and fishes) were collected from Pitchavaram mangrove ecosystem and subjected to analyses of 210 Po. The concentration of 210 Po in water and sediment was 1.8 mBq/l and 2.6 Bq/kg respectively. It was observed that the muscle and soft tissues of animals concentrated a higher level of 210 Po than the hard parts like shells and bones. The ranges of 210 Po activity in biological samples were analysed in crustaceans (muscle: 72.3-227.7 Bq/kg and exoskeleton 31.2-92.3 Bq/kg), molluscs (soft tissue: 295-584.7 Bq/kg and shell: 2.9-11.9 Bq/kg) and fishes (muscle: 14.3- 43.7 Bq/kg and bone: 10.3-21.9 Bq/kg). The oyster Crassostrea madrasensis was identified to concentrate higher level of 210 Po in their soft tissues, suggesting that this could serve as a bioindicator organism. The study demonstrates that the 210 Po Pitchavaram mangrove has been rather very low as compared to adjacent Kalpakkam coast on the North and Gulf of Mannar on the South. (author)

  15. Abstracts of the Conference on Mechanisms of DNA Repair and Mutagenesis on the 100. Anniversary of the Discovery of Polonium and Radium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The conference covered various aspects of mutagenesis and mechanisms of DNA repair. UV and ionizing radiation were use to induce DNA lesions in bacteria, yeast and cell cultures of higher organisms. This allows study of influence of mutations on particular processes in the cell. Mechanisms of resistance were also investigated. Biological investigations were performed using labelled compounds.

  16. A comparative study on the internal dose due to Polonium-210 in the ecosystem of Athangarai estuary (Palk Strait) and Punnaikayal estuary (Gulf of Mannar), India

    International Nuclear Information System (INIS)

    Krishnamoorthy, R.; Ravikumar, S.; Shahul Hameed, P.

    2006-01-01

    The present study deals with Committed Effective Dose (CEO) due to 210 Po through the dietary intake of seafood from the Athangarai estuary and Punnaikayal estuary. The concentration of 210 Po was determined in selected species of estuarine organisms. It is found that the 210 Po dose due to the consumption of estuarine food varied from 49.9 to 552.1 μSv/y in Athangarai estuary and 148.0 to 406.9 μSv/y in Punnaikayal estuary. Concentration of 210 Po in the muscle of edible organisms in Athangarai estuary and Punnaikayal estuary ranged from 20.8 to 181.3 Bq/kg and 88.1 to 242.2 Bq/kg respectively. Higher 210 Po dose is expected via the consumption of fish Sandinella longiceps (552.1 μSv/y) in Athangarai estuary and Thyssa malabarica (406.9 μSv/y) in Punnaikayal estuary. In the present study higher level of 210 Po concentration was observed in Plankton feeding fish of both the estuary. (author)

  17. Some aspects of the bioaccumulation of polonium-210 and lead-210 in the gill of the fish Macrodon ancylodon (Block and Schneider, 1801)

    International Nuclear Information System (INIS)

    Pereira, Wagner de Souza

    1999-01-01

    210 Po and its grandfather 210 Pb are natural radionuclides from the 238 U family. The former is of considerable radio-biological relevance because of its very easy absorption by almost all living organisms and because of its high radiotoxicity, being considered as the major contributor to α-irradiation in the great majority of organisms. On the contrary, the low energy β-emitter 210 Pb is less efficiently absorbed; its biological importance results from the fact that it decays to 210 Po, being one of the sources of the latter in all living beings. The concentrations of 210 Po and 210 Pb in the gills of Macrodon ancylodon (known as 'pescadinha') from Sepetiba Bay (80 Km SW of Rio de Janeiro, Brazil) were determined monthly, looking for: eventual variations along the time of their respective bioaccumulation; variations of their relative bioaccumulation ( 210 Po/ 210 Pb ratios); and correlations between levels of 210 Po and 210 Pb and biometric parameters such as length and weight. Thus, the concentrations of 210 Po and 210 Pb in gills of M. ancylodon were determined monthly during respectively 16 and 12 months. The overall mean concentrations of 210 Po and 210 Pb were respectively of 22.41 +/- 14.57 mBq/g (range : 12.69 +/- 4.76 mBq/g in May 98 to 34.84 +/- 15.72 mBq/g in January 98) and 2.48 +/- 1.92 mBq/g (range : 1.62 +/- 0.85 mBq/g in September 97 to 4.89 +/- 2.85 mBq/g in May 97). Statistical analysis of the radiometric parameters ( 210 Po activity, 210 Pb activity and 210 Po/ 210 Pb ratio) showed that there was no detectable dependence of 210 Po or 210 Pb accumulation along the time. However, the 210 Po/ 210 Pb ratios were higher during summer and winter (approximately 22), and lower during spring and autumn (approximately 10). This suggested that some seasonal variations must indeed occur and these might be related to the heavy rainfalls that occur during summer and winter. On the other hand, no correlations could be observed between the biometric parameters (weight and length) and the radiometric ones. Hence, the levels of 210 Po and 210 Pb were not related to the age of the fishes. The gill of M. ancylodon may thus be considered as a good bioindicator for the presence of these two radio-nuclides in studied area. (author)

  18. Abstracts of the Conference on Mechanisms of DNA Repair and Mutagenesis on the 100. Anniversary of the Discovery of Polonium and Radium

    International Nuclear Information System (INIS)

    1997-01-01

    The conference covered various aspects of mutagenesis and mechanisms of DNA repair. UV and ionizing radiation were use to induce DNA lesions in bacteria, yeast and cell cultures of higher organisms. This allows study of influence of mutations on particular processes in the cell. Mechanisms of resistance were also investigated. Biological investigations were performed using labelled compounds

  19. Polonium-210 and lead-210 in food and tobacco products: a review of parameters and an estimate of potential exposure and dose

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A.P.

    1983-07-01

    Food-chain transport of Pb-210 and Po-210 from soil to edible plant parts and from animal feed to meat and milk were evaluated from a review of literature. The degree of transfer was characterized by estimating concentration factors (unweighted arithmetic means) as well as the transfer coefficients B/sub v/, B/sub r/ (unweighted geometric means, f/sub m/ and f/sub f/ (unweighted arithmetic means). Global dietary intake of Pb-210 and Po-210 was also summarized, and 50-year dose estimates to target organs calculated. The greatest estimated ingestion doses were those to populations with large dietary complements of animal protein in the form of seafood (Japan) or caribou/reindeer muscle and organ meats (Arctic Eskimos and Lapps). The magnitude of this latter source illustrates the importance of simple food chains in generating significant exposures to populations dependent upon them. The origin and magnitude of inhalation exposure and dose from tobacco products was also assessed. For the majority of internal organs evaluated, the dose resulting from smoking commercially available tobacco products is comparable to or greater than the dose estimates for ingestion of naturally occurring dietary Pb-210 and Po-210.

  20. Abstracts of the Conference on Mechanisms of DNA Repair and Mutagenesis on the 100. Anniversary of the Discovery of Polonium and Radium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    The conference covered various aspects of mutagenesis and mechanisms of DNA repair. UV and ionizing radiation were use to induce DNA lesions in bacteria, yeast and cell cultures of higher organisms. This allows study of influence of mutations on particular processes in the cell. Mechanisms of resistance were also investigated. Biological investigations were performed using labelled compounds.

  1. Polonium-210 and lead-210 in food and tobacco products: a review of parameters and an estimate of potential exposure and dose

    International Nuclear Information System (INIS)

    Watson, A.P.

    1983-07-01

    Food-chain transport of Pb-210 and Po-210 from soil to edible plant parts and from animal feed to meat and milk were evaluated from a review of literature. The degree of transfer was characterized by estimating concentration factors (unweighted arithmetic means) as well as the transfer coefficients B/sub v/, B/sub r/ (unweighted geometric means, f/sub m/ and f/sub f/ (unweighted arithmetic means). Global dietary intake of Pb-210 and Po-210 was also summarized, and 50-year dose estimates to target organs calculated. The greatest estimated ingestion doses were those to populations with large dietary complements of animal protein in the form of seafood (Japan) or caribou/reindeer muscle and organ meats (Arctic Eskimos and Lapps). The magnitude of this latter source illustrates the importance of simple food chains in generating significant exposures to populations dependent upon them. The origin and magnitude of inhalation exposure and dose from tobacco products was also assessed. For the majority of internal organs evaluated, the dose resulting from smoking commercially available tobacco products is comparable to or greater than the dose estimates for ingestion of naturally occurring dietary Pb-210 and Po-210

  2. Some aspects of polonium-210 and lead-210 bioaccumulation in the gills of the fish Macrodon ancylodon ( Block and Schneider, 1801)

    International Nuclear Information System (INIS)

    Pereira, Wagner S.; Kelecom, Alphonse; Gouvea, Rita C.S.; Santos, Pedro L. dos

    2000-01-01

    The concentrations of 210 Po and 210 Pb and the ratios between these radionuclides have been determined monthly from February 1997 to May 1998 in the gills of the fish Macrodon ancylodon, collected in the bay of Sepetiba (State of Rio de Janeiro). The variations in the biological accumulation of 210 Po and 210 Pb were analysed along the time and correlated to the weight and length of the fishes. (author)

  3. Radiation Dose and Risk Assessments from Polonium-210 in Green Mussels (Perna viridis) and Seafood Consumers Living nearby the Industrial Area in Chonburi Province, Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Tumnoi, Y.; Phaopeng, N. [Office of Atoms for Peace - OAP (Thailand)

    2014-07-01

    Marine environmental samples including seawater (filtered and unfiltered), suspended particles, and green mussels (Perna viridis) were collected from Sriracha and Angsira areas located in Chonburi province in order to determine Po-210 radioactivity. The former was chosen because it is generally believed that this area has been contaminated by one of the largest industrial estates in Thailand and others human-activities (non-nuclear activities) nearby such as oil refineries and Coal Power Plants. Discharges, ashes, and wastes released from these activities may result in an increase of Po-210 concentration in marine environment when compared to other areas. The later was designated to serve as a control site in this study since this area is unlikely to be impacted by industrial activities. Our results revealed that, in the filtered seawater, averaged values of Po-210 level were 0.26 + 0.14 mBq/L (Sriracha) and 0.56 + 0.42 mBq/L (Angsira) and, in the unfiltered seawater, means of Po-210 radioactivity were 2.37 + 0.32 mBq/L (Sriracha) and 4.20 + 2.78 mBq/L (Angsira). Furthermore, the suspended particles contained Po-210 concentrations with averaged values of 14.11 + 8.87 Bq/kg dw (Sriracha) and 102.21 + 51.49 Bq/kg dw (Angsira) while averaged Po-210 levels of 35.74 + 17.53 Bq/kg dw (Sriracha) and 71.12 + 62.88 Bq/kg dw (Angsira) were found in the green mussels examined. The present finding indicates that there is no radiological impact caused by those human activities to the marine environment at Sriracha. Radiation dose assessment was also performed in both the green mussels and human who consume green mussels. The results show that the green mussels farmed at Sriracha and Angsira received averaged radiation dose rates from Po-210 at 0.0007 and 0.0015 mGy/d, respectively. In addition, our results reveal that populations living in Chonburi province and ingesting the green mussels from these 2 locations received radiation dose rates from Po-210 at the means of 44.25 and 26.54 μSv/y. Higher dose rates would be obtained when consuming immediately or a couple day after the harvest while the lower would be obtained when the mussels are stored for 90 days prior to ingestion. These dose rates are well below the dose limits for aquatic organisms which are 10 mGy/d and 10 μGy/h and for the general public which is 1 mSv/y. Therefore, it can be concluded here that the green mussels from both areas are radiologically healthy and do not cause any radiation effects to the seafood consumers. Document available in abstract form only. (authors)

  4. Spectroscopy of exotic nuclei with A {approx} 190: single particle states and collective properties of {sup 187,189}Bi and {sup 188}Pb; Spectroscopie de noyaux exotiques dans la region de masse A {approx} 190: la structure des isotopes {sup 187,189}Bi et {sup 188}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Huerstel, A

    2002-11-01

    This thesis is devoted to the study of very neutron deficient nuclei in the lead region of the nuclear chart and more precisely to the investigation of the single particle states and collective properties of the {sup 187,189}Bi isotopes by gamma-ray spectroscopy. These nuclei were produced via fusion-evaporation reaction induced by a krypton beam on a silver target. In this mass region, the cross section for producing these nuclei are very low, of the order of a few micro-barns, making experimental studies very difficult. The identification of the nuclei was done using the very powerful RDT (Recoil Decay Tagging) technique, based on the selection of the isotopes through their characteristic alpha-particle decays. The experiments were performed at the university of Jyvdskyla (Finland) with the facility combining the gamma-ray spectrometer JUROSPHERE and the magnetic gas-filled separator RITU. Isomeric states were observed in both nuclei and their life-times measured. The systematics of individual proton states in odd-mass bismuth isotopes have been reproduced with a shell model up to 20 neutrons away from the valley of stability. Furthermore, rotational bands, a signature of collective nuclear motion, have been established for the first time in these nuclei. The interpretation of these results led to the conclusion that {sup 187,189}Bi have a prolate shape at low excitation energy, unlike the heavier bismuth isotopes which have been interpreted to have oblate deformation, implying a shape transition in this mass region. Hartree-Fock-Bogolyubov calculations are consistent with the experimental indication of shape coexistence, as seen in the neighbouring even-even lead nuclei. (author)

  5. β-Decay half-lives and nuclear structure of exotic proton-rich waiting point nuclei under rp-process conditions

    Science.gov (United States)

    Nabi, Jameel-Un; Böyükata, Mahmut

    2016-03-01

    We investigate even-even nuclei in the A ∼ 70 mass region within the framework of the proton-neutron quasi-particle random phase approximation (pn-QRPA) and the interacting boson model-1 (IBM-1). Our work includes calculation of the energy spectra and the potential energy surfaces V (β , γ) of Zn, Ge, Se, Kr and Sr nuclei with the same proton and neutron number, N = Z. The parametrization of the IBM-1 Hamiltonian was performed for the calculation of the energy levels in the ground state bands. Geometric shape of the nuclei was predicted by plotting the potential energy surfaces V (β , γ) obtained from the IBM-1 Hamiltonian in the classical limit. The pn-QRPA model was later used to compute half-lives of the neutron-deficient nuclei which were found to be in very good agreement with the measured ones. The pn-QRPA model was also used to calculate the Gamow-Teller strength distributions and was found to be in decent agreement with the measured data. We further calculate the electron capture and positron decay rates for these N = Z waiting point (WP) nuclei in the stellar environment employing the pn-QRPA model. For the rp-process conditions, our total weak rates are within a factor two compared with the Skyrme HF +BCS +QRPA calculation. All calculated electron capture rates are comparable to the competing positron decay rates under rp-process conditions. Our study confirms the finding that electron capture rates form an integral part of the weak rates under rp-process conditions and should not be neglected in the nuclear network calculations.

  6. Measurements of fusion cross sections in the systems {sup 58,64}Ni +, {sup 78,86}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Rehm, K.E.; Jiang, C.L.; Esbensen, H. [and others

    1995-08-01

    We investigated the nuclear structure dependence of the sub-barrier fusion enhancement in heavy-ion induced reactions by studying the systems {sup 58,64}Ni + {sup 78,86}Kr at energies in the vicinity of the Coulomb barrier. These {sup 78,86}Kr selected because, similar to the Mo case discussed isotopes were above, there are strong changes in nuclear structure as a function of the neutron number. However, contrary to Mo, where the {open_quotes}softness{close_quotes} of the nucleus increases with higher neutron number, the most collective nucleus for the Kr case is the neutron-deficient {sup 78}Kr. The experiment was performed with Kr beams from the positive-ion injector using enriched {sup 78,86}Kr gas in the ECR ion source. The separation of evaporation residues from the elastically-scattered particles was achieved by using their difference in time-of-flight and magnetic rigidity in the gas-filled spectrograph. The excitation functions for the four systems were compared to coupled-channels calculations including inelastic excitations of one- and two-phonon states in projectile and target. For systems involving {sup 86}Kr, good agreement between theory and experiment is obtained, while for {sup 78}Kr + {sup 58,64}Ni an additional enhancement of the cross sections persisted at the lowest energies. It was found that this fusion enhancement correlates with the nuclear structure of the individual nucleus. Characterizing the structure of vibrational even-even nuclei by their restoring force parameter C{sub 2}, which can be calculated from the energy of the lowest 2{sup +} state and the associated B(E2) value, one observes that nuclei with small C{sub 2} values exhibit a large sub-barrier fusion enhancement, while nuclei with high values of C{sub 2} (usually closed-shell nuclei), show smaller fusion yields.

  7. Optimization of krypton yields for rp-process studies at ISOLDE (CERN)

    CERN Document Server

    Kankainen, Anu Kristiina; Fraile-Prieto, L M; Jokinen, A; Leitner, M S; Oinonen, M; Peräjärvi, K; Ravn, H L

    2004-01-01

    The production of neutron-deficient krypton isotopes having astrophysical importance has been studied at the ISOLDE PBS facility at CERN. To investigate several effects on the yield a Monte Carlo code has been extensively applied.

  8. The structure of nuclei far from beta stability

    International Nuclear Information System (INIS)

    Zganjar, E.F.

    1991-01-01

    This report discusses the structural of nuclei for from beta stability of the following isotopes: thallium isotopes; mercury isotopes; gold isotopes; platinum isotopes; iridium isotopes; the neutron deficient rare-earth, Z = 57-72 region, and the neutron deficient Z = 50-56 region; also discussed are in-beam spectroscopy in the A = 70 region and shape coexistence, intruder states, and EO transitions

  9. Shell structure in the vicinity of the doubly magic {sup 100}Sn via Coulomb excitation at PreSPEC

    Energy Technology Data Exchange (ETDEWEB)

    Guastalla, Giulia

    2014-11-17

    The PreSPEC setup in combination with the high intensity primary beams available at GSI provided unique opportunities for the key nuclear structure studies on exotic nuclei. The experiment performed on the neutron deficient {sup 104}Sn aimed to deduce the reduced transition probability of the first excited 2{sup +} state quantified by the B(E2; 0{sup +} → 2{sup +}) value. This result is the central point in the discussion of the evolution of nuclear structure in proximity of the doubly magic nucleus {sup 100}Sn. As {sup 100}Sn is not yet accessible for such measurements, a series of experiments have been performed for neutron-deficient Sn isotopes over the past few years. These data showed excessive experimental B(E2) strength compared to shell model calculations below neutron number N=64 and they are therefore not excluding a constant or even increasing collectivity below {sup 106}Sn. Hence, the measurement of the B(E2) value in the next even-even isotope toward {sup 100}Sn, i.e. {sup 104}Sn, was a crucial step to verify the robustness of the shell gap of {sup 100}Sn. Moreover, {sup 104}Sn is the heaviest isotope of the Sn isotopic chain for which a shell model calculation without significant truncation of the valence space can be performed and therefore with this experimental value the validity of Large Scale Shell Model (LSSM) calculations could be tested. As a main result of the experiment a B(E2) value corresponding to 0.10(4) e{sup 2}b{sup 2} has been extracted for {sup 104}Sn. The experimental value showed a very good agreement with the predicted one and, despite the large error bar, it clearly established a downward trend of the B(E2) values of the Sn isotopic chain toward A=100. This implied enhanced stability of the N = Z = 50 shell closure against ph-excited quadrupole modes. However, an experiment of this kind is very challenging for several reasons. First, {sup 104}Sn lies in proximity of the proton drip line and has therefore a small production

  10. Polonium-210 and lead-210 in the Southern Polar Ocean: Naturally occurring tracers of biological and hydrographical processes in the surface waters of the Antarctic Circumpolar Current and the Weddell Sea

    International Nuclear Information System (INIS)

    Friedrich, J.

    1997-01-01

    In this thesis the distribution of 210 Po and 210 Pb in the upper 600 m of the Antarctic Circumpolar Current and the Weddell Sea was investigated along north-south transects in austral spring and autumn. 210 Po and 210 Pb can serve as sensitive tracers for the special hydrographic conditions of the Antarctic Circumpolar Current and the Weddell Sea as well as for biological processes during phytoplankton blooms. The 210 Po/ 210 Pb disequilibrium was used as a tracer for particle export. This tracer integrates export on a timescale of 276 days because of the 138 day half-life of 210 Po and complements the 234 Th/ 238 U disequilibrium as another tracer for plankton production and export on a shorter timescale of several weeks. (orig.) [de

  11. Polonium-210 and other radionuclides in terrestrial, freshwater and brackish environments Results from the NKS project GAPRAD (Filling knowledge gaps in radiation protection methodologies for non-human biota)

    International Nuclear Information System (INIS)

    Gjelsvik, R.; Brown, J.; Holm, E.; Roos, P.; Saxen, R.; Outola, I.

    2012-01-01

    The background and rationale to filling knowledge gaps in radiation protection methodologies for biota are presented. Concentrations of Po-210 and Pb-210 are reported for biota sampled in Dovrefjell, Norway and selected lake and brackish ecosystems in Finland. Furthermore, details in relation to Po-210 uptake and biokinetics in humans based on experimental studies are recounted. (Author)

  12. Polonium-210 and other radionuclides in terrestrial, freshwater and brackish environments Results from the NKS project GAPRAD (Filling knowledge gaps in radiation protection methodologies for non-human biota)

    Energy Technology Data Exchange (ETDEWEB)

    Gjelsvik, R; Brown, J; Holm, E; Roos, P; Saxen, R; Outola, I

    2012-01-15

    The background and rationale to filling knowledge gaps in radiation protection methodologies for biota are presented. Concentrations of Po-210 and Pb-210 are reported for biota sampled in Dovrefjell, Norway and selected lake and brackish ecosystems in Finland. Furthermore, details in relation to Po-210 uptake and biokinetics in humans based on experimental studies are recounted. (Author)

  13. Application of alpha spectrometry to the discovery of new elements by heavy-ion-beam bombardment

    International Nuclear Information System (INIS)

    Nitschke, J.M.

    1983-05-01

    Starting with polonium in 1898, α-spectrometry has played a decisive role in the discovery of new, heavy elements. For even-even nuclei, α-spectra have proved simple to interpret and exhibit systematic trends that allow extrapolation to unknown isotopes. The early discovery of the natural α-decay series led to the very powerful method of genetically linking the decay of new elements to the well-established α-emission of daughter and granddaughter nuclei. This technique has been used for all recent discoveries of new elements including Z = 109. Up to mendelevium (Z = 101), thin samples suitable for α-spectrometry were prepared by chemical methods. With the advent of heavy-ion accelerators new sample preparation methods emerged. These were based on the large momentum transfer associated with heavy-ion reactions, which produced energetic target recoils that, when ejected from the target, could be thermalized in He gas. Subsequent electrical deposition or a He-jet technique yielded samples that were not only thin enough for α-spectroscopy, but also for α- and #betta#-recoil experiments. Many variations of these methods have been developed and are discussed. For the synthesis of element 106 an aerosol-based recoil transport technique was devised. In the most recent experiments, α-spectrometry has been coupled with the magnetic analysis of the recoils. The time from production to analysis of an isotope has thereby been reduced to 10 - 6 s; while it was 10 - 1 to 10 0 s for He-jets and 10 1 to 10 3 s for rapid chemical separations. Experiments are now in progress to synthesize super heavy elements (SHE) and to analyze them with these latest techniques. Again, α-spectrometry will play a major role since the expected signature for the decay of a SHE is a sequence of α-decays followed by spontaneous fission

  14. Abstracts of Papers Submitted in 1978 for Publication,

    Science.gov (United States)

    1978-01-01

    210 and Polonium - 210 as Marine...34.." . .." . .• . ’... . .. X. . ’-"..’-..- . - .>I-.A7.’ -~. .-.. .. . .< .- , ,.. . -’ ~ ~ \\ - & . .x. \\ , ,, .. . . . ... . .. . C-22 i- LEAD- 210 AND POLONIUM - 210 AS...Herbivore Food Preference B-13 Mary E. Nicotri High Benzo(a)pyrene Hydroxylase Activity in the Marine Teleost Fish Stenotomus versicotor . . .

  15. JPRS Report, Proliferation Issues

    Science.gov (United States)

    1993-03-22

    delivering abroad polonium sources (with experimental physics. polonium - 210 radioisotopes) for several decades now. They are mostly used in space...34sensations"-from attempts to steal pre- gorod a short while ago. It claimed that the load con- cious and rare-earth metals to food stocks which have

  16. The Semipalatinsk Nuclear Test Site: Through My Own Eyes

    Science.gov (United States)

    2014-07-01

    compounds as strontium-90, zirconium-95, cesium-137, carbon-14, plutonium-239, polonium - 210 , and lead- 210 . Plutonium and lead (sic) have not been studied as...times greater than in the population in Europe. This means that the sheep and the kangaroo feed on plants which are filled with lead- 210 and polonium ...9 2.3 POISONED FOOD

  17. Measurement of radon daughters in air samples by alpha spectroscopy

    International Nuclear Information System (INIS)

    Acena, M.L.; Crespo, M.T.

    1989-01-01

    The concentration of radon progeny in air has been determined by alpha spectrometry measurement of polonium 214 and polonium 218. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter (Author)

  18. Mass measurements on short-lived Cd and Ag nuclides at the online mass spectrometer ISOLTRAP

    International Nuclear Information System (INIS)

    Breitenfeldt, Martin

    2009-01-01

    In the present work, mass determinations of the eleven neutron-deficient nuclides 99-109 Cd, of ten neutron-rich silver nuclides 112,114-121,123 Ag, and seven neutron-rich cadmium nuclides 114,120,122-124,126,128 Cd are reported. Due to the clean production of the neutron-deficient nuclides it was possible to reduce the experimental uncertainties down to 2 keV, whereas the measurements of neutron-rich nuclides were hampered by the presence of contaminations from more stable In and Cs nuclides. In the case of 99 Cd and 123 Ag the masses were determined for the first time and for the other nuclides the mass uncertainties could be reduced by up to a factor of 50 as in the case of 100 Cd. In the case of a potential isomeric mixture as for 115,117,119 Ag and 123 Cd, where no assignment to either the ground state or the excited state was possible, the experimental results were adjusted accordingly. Afterwards all results were included in the framework of the atomic-mass evaluation and thus linked and compared with other experimental data. In the case of a potential isomeric mixture as for 115,117,119 Ag and 123 Cd, where no assignment to either the ground state or the excited state was possible, the experimental results were adjusted accordingly. Afterwards all results were included in the framework of the atomic-mass evaluation and thus linked and compared with other experimental data. In the case of the neutron-deficient Cd nuclides a conflict between the mass values obtained in the present work and those published by the JYFLTRAP group [EEH + ] could be solved by performing an atomic-mass evaluation. Thus, it was revealed that reason for the conflict was a different value of the JYFLTRAP reference mass 96 Mo. Furthermore, a reduction of the mass uncertainty and a slight increase of the mass of 100 In were obtained. These mass measurements are an important step towards an understanding of the physics of the rp process that will enable a more reliable determination of

  19. A review of radio chemical analysis and estimation of 210Po in soil matrices

    Directory of Open Access Journals (Sweden)

    N.K. Sethy

    2015-10-01

    Full Text Available The naturally occurring radionuclide 210Po, arising from the uranium–radium decay series, provides a considerable contribution to the radiation exposure to humans. Polonium is analyzed for a variety of purposes, including for radiological impact assessment or as a tracer of environmental processes. Losses of polonium may occur at temperatures above 100 °C, depending on conditions, requiring particular care in sample preparation and treatment. There has been little development regarding analysis of polonium in environmental samples since 1960 as radiochemical analysis of polonium is quite straight forward due to easy of source preparation through auto-deposition on to metal surfaces. In this paper a brief review of estimation of polonium in the soil samples have given emphasis.

  20. Nuclear structure from radioactive decay. Annual progress report

    International Nuclear Information System (INIS)

    Wood, J.L.

    1986-01-01

    The primary focus has been studies of intruder states and shape coexistence in the neutron-deficient Z equal to 82 region. Most notably, the structure of the neutron-deficient Au isotopes has been studied by on-line decay scheme spectroscopy of mass-separated isotopes at UNISOR, by on-line low-temperature nuclear orientation of mass-separated isotopes at LISOL, and by on-line laser atomic hyperfine spectroscopy of mass-separated isotopes at ISOLDE. Theoretical studies of neutron-deficient Au isotopes have been made. The most dramatic result is the observation of a sudden large increase in the mean-square charge radius between 187 Au and 186 Au, seen in the laser spectroscopy measurements as ISOLDE

  1. 210 Po content in tobacco cigarettes in Thailand

    International Nuclear Information System (INIS)

    Chittaporn, P.

    1985-12-01

    A technique has been modified to measure polonium-210 in tobacco cigarettes manufactured in Thailand. Polonium-210 which is equilibrated with polonium-208 tracer added before processing for chemical separation is isolated and quantitatively deposited on a nickel disc from concentration HCl acid. The plated disc is counted on an alpha spectrometer. The alpha resolution of polonium on nickel disc of the surface barrier detector with active area 300 mm 2 was about 30 keV. A chemical blank was processed with each tobacco sample. The average recovery yield was about 70 percent. The lower limit of detection as determined from average chemical blank values 0.058+-0.006 pCi was 0.02 pCi for a 24 hour count. The polonium-210 content in 9 brand names cigarette manufactured in Thailand were varied from 0.121 pCi/g tobacco to 0.282 pCi/g. tobacco, and in 6 brand names shredded tobacco popularize as tobacco cigarette in upcountry were varied from 0.303 pCi/g. tobacco to 0.446 pCi/g. tobacco. In summary polonium-210 content in tobacco cigarettes manufactured in Thailand are ranged from 0.121 pCi/g. tobacco to 0.446 pCi/g. tobacco. The average polonium-210 content for 15 brand names tobacco cigarette is 0.273+-0.10 pCi/g. tobacco

  2. Laser spectroscopy of gallium isotopes using the ISCOOL RFQ cooler

    CERN Multimedia

    Blaum, K; Kowalska, M; Ware, T; Procter, T J

    2007-01-01

    We propose to study the radioisotopes of gallium (Z=31) by collinear laser spectroscopy using the ISCOOL RFQ ion cooler. The proposed measurements on $^{62-83}$Ga will span both neutron-deficient and neutron-rich isotopes. Of key interest is the suggested development of a proton-skin in the neutron-deficient isotopes. The isotope shifts measured by laser spectroscopy will be uniquely sensitive to this feature. The measurements will also provide a wealth of new information on the gallium nuclear spins, static moments and nuclear charge radii.

  3. Description of the Gamov-Teller β+-decay of tin isotopes

    International Nuclear Information System (INIS)

    Kuz'min, V.A.; Solov'ev, V.G.

    1988-01-01

    The integrated log(ft) values of Gamow-Teller β + decays of the neutron-deficient tine isotopes are calculated in the random phase approximation with particle-hole and particle-particle residual interactions which parameters have been fixed earlier. For |g A /g V |=1 and |g A /g V |=1.263 a good correspondence with the experimental data is obtained for 104,106,108 Sn and a prediction is made for 102 Sn. It is shown that one cannot define from the rate of neutron-deficient nuclei β + decay the renormalization of the axial-vector weak interaction constant g A

  4. The National Medical Cyclotron - An Australian experience in technology

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, R K [Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia). National Medical Cyclotron

    1998-12-31

    The establishment of the National Medical Cyclotron (NMC) in the early 1990`s was the practical outcome of a vision, held by nuclear medicine professionals, to complement the available neutron-rich radionuclides produced in Australia, with neutron-deficient radionuclides. The NMC is operated by the Australian Nuclear Science and Technology Organisation (ANSTO) in collaboration with the Royal Prince Alfred Hospital (RPAH) in Sydney where the PET department is able to use the short-lived radiotracers to good advantage. Neutron-deficient radionuclides, are also produced by the NMC laboratories. The cyclotron-generated radionuclides are used in over 70,000 patient studies per year. 7 refs., 1 tab.

  5. The National Medical Cyclotron - An Australian experience in technology

    International Nuclear Information System (INIS)

    Barnes, R. K.

    1997-01-01

    The establishment of the National Medical Cyclotron (NMC) in the early 1990's was the practical outcome of a vision, held by nuclear medicine professionals, to complement the available neutron-rich radionuclides produced in Australia, with neutron-deficient radionuclides. The NMC is operated by the Australian Nuclear Science and Technology Organisation (ANSTO) in collaboration with the Royal Prince Alfred Hospital (RPAH) in Sydney where the PET department is able to use the short-lived radiotracers to good advantage. Neutron-deficient radionuclides, are also produced by the NMC laboratories. The cyclotron-generated radionuclides are used in over 70,000 patient studies per year

  6. Assessment of 210Po in agricultural soils and marine sediments of the Atlantic and Pacific oceans of Guatemala

    International Nuclear Information System (INIS)

    Garcia Vela, A.G.

    1999-01-01

    A radiochemical method consisting of 210 Polonium extraction was made to measure radioactivity in samples of soil and marine sediments of Atlantic and Pacific Ocean. The solution of polonium it was treated to obtain the deposition of the metal over a zinc disc and was measured by alpha espectrometry system based on Planar Ion Planted Silice (PIPS) system. The concern about cultivated soils its consuption products from sea and soil come from these sources. The results shows that activity of 210 Polonium in agricultural soils and marine sediments are below of ALI recommended by international standards

  7. The Bonebrake Theological Seminary: Top-Secret Manhattan Project Site

    Science.gov (United States)

    Sopka, Katherine R.; Sopka, Elisabeth M.

    2010-09-01

    We discuss the top-secret Manhattan Project site established at the Bonebrake Theological Seminary in 1943 in Dayton, Ohio, where research on polonium and its production was carried out. The polonium produced there was then transported to Los Alamos to be used in a polonium-beryllium neutron source whose purpose was to ignite the plutonium implosion bomb that would be dropped on Nagasaki, Japan, on August 9, 1945. Our account is based primarily on the recollections of John J. Sopka, research physicist at the Bonebrake laboratory.

  8. Dietary intake of natural radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Smith-Briggs, J L; Bradley, E J [National Radiological Protection Board, Chilton (UK)

    1984-09-01

    The levels of the natural radionuclides, radium-226, lead-210 and polonium-210 were measured in food samples collected for a National Food Survey, thus reflecting current consumption patterns in the UK. Daily intakes of radium-226, lead-210 and inferred values of polonium-210 were calculated for 20 food groups. From these data, the annual effective dose equivalents from radium-226, lead-210 and polonium-210 in the UK diet were estimated to be 3..mu..Sv, 41..mu..Sv and 13..mu..Sv respectively.

  9. Environmental Assessment for Increased Depleted Uranium Use on Target 63-10, Nevada Test and Training Range

    Science.gov (United States)

    2006-09-01

    min. β Bismuth-214 19.9 min. β Polonium -214 1.5 x 10-4 sec. α Lead- 210 22 years β Bismuth- 210 5 days β Polonium - 210 140 days α Lead-206 stable...Uranium-234 2.5 x 105 years α Thorium-230 7.7 x 104 years α Radium-226 1600 years α Radon-222 3.8235 days α Polonium -218 3.05 min. α Lead-214 26.8...the degraded areas where ordnance delivery occurs. This also applies to DU use. These areas do not provide food or habitat resources likely to

  10. Dietary intake of natural radionuclides

    International Nuclear Information System (INIS)

    Smith-Briggs, J.L.; Bradley, E.J.

    1984-01-01

    The levels of the natural radionuclides, radium-226, lead-210 and polonium-210 were measured in food samples collected for a National Food Survey, thus reflecting current consumption patterns in the UK. Daily intakes of radium-226, lead-210 and inferred values of polonium-210 were calculated for 20 food groups. From these data, the annual effective dose equivalents from radium-226, lead-210 and polonium-210 in the UK diet were estimated to be 3μSv, 41μSv and 13μSv respectively. (U.K.)

  11. A novel technique for the simultaneous determination of 210Pb and 210Po using a crown ether

    International Nuclear Information System (INIS)

    Vajda, N.; LaRosa, J.; Zeisler, R.; Danesi, P.; Kis-Benedek, Gy.

    1997-01-01

    A simple radiochemical procedure has been developed to separate lead and polonium simultaneously from different environmental and biological materials. After adding 208 Po tracer and lead carrier, samples are decomposed using mineral acids. Lead and polonium are selectively retained from 2M HCl solution by the bis-4,4'(5')-t-butyl-cyclohexano-18-crown-6-ether; polonium is stripped with 6 M HNO 3 while lead is stripped with 6 M HCL solution. A polonium source is prepared by spontaneous deposition onto a silver disk. The activity concentration of 210 Po is determined by isotope dilution alpha spectrometry. Lead is precipitated as oxalate; the chemical recovery is determined by gravimetry. The activity concentration of 210 Pb is calculated from the liquid scintillation spectrum. (author)

  12. On reaction of titanium polonides with carbon dioxide

    International Nuclear Information System (INIS)

    Abakumov, A.S.; Malyshev, M.L.; Reznikova, N.F.

    1986-01-01

    The reaction between titanium polonides and carbon dioxide has been studied by comparing titanium polonide thermal resistance in vacuum and in carbon dioxide. The investigation has shown that titanium mono- and semipolonides fail at temperatures below 350 deg C. Temperature dependence of polonium vapor pressure prepared at failure of the given polonides is determined by the radiotensiometry in carbon dioxide. Enthalpy calculated for this dependence is close to the enthalpy of elementary polonium evaporation in vacuum

  13. Radioactivity and Environmental Security in the Oceans: New Research and Policy Priorities in the Arctic and North Atlantic

    Science.gov (United States)

    1993-06-09

    combined with pictures of fishing activities and further a dish I with fish with a question-mark of the edibility of the food are not 210 1...alpha and beta activity. In addition, individual analyses were conducted for lead- 210 , polonium - 210 , strontium-90, I and radium-226, as well as for...as radium-226, lead- 210 , polonium - 210 , and potassium-40. The cosmogenic nuclides m include tritium and carbon-14. In the marine environment, the

  14. Space Handbook,

    Science.gov (United States)

    1985-01-01

    thle early life * of" the system. Figure 4-2 shows the variation in power output for polonium - 210 (Po- 210 ) with a 138-day half-life, curium-242 (Cm...miles above the earth’s surface. Above this altitude they must take everything they need with them. The environment will supply them with neither food ...can move large payloads through space. The radioisotope heat cycle engines use high-energy particle sources such as plutonium and polonium . The walls

  15. USSR Report, Chemistry

    Science.gov (United States)

    1985-08-16

    of the thermal interaction of polonium - 210 with palladium and iridium. The vacuum-thermal method of direct synthesis was used, a study of the... Polonium -Palladium, Iridium Systems (A. S. Abakumov, M. L. Malyshev, et al.; RADIOKHIMIYA, No 2, Mar-Apr 85) 82 Migration of Radioactive and...and energy complex, machine building, light and food industry, agriculture, transportation, and the production of household articles. Working to meet

  16. Journal of Special Operations Medicine. Training Supplement: Tactics, Techniques, and Procedures, Volume 8 Edition 4, Fall 2008

    Science.gov (United States)

    2008-01-01

    Anthrax, or Polonium 210 . Incidental events such as the postal letter to Senator Daschle that occurred in Washington, D.C. in October 2001 and the use of... Polonium 210 against Alexander Litvinenko in November 2006 show the potential of future insurgents’ willingness to conduct mass killings. The...authors as well (Navein et al., 2003). Hemostatic Agents No hemostatic agents had been approved by the Food and Drug Administration (FDA) and proven to

  17. Current Research Activities.

    Science.gov (United States)

    1975-02-01

    and PoZonium- 210 Investigations of lead- 210 and polonium - 210 in sediments offshore of the 4 Columbia River are under way, with the dual aims of...Geochemical bepb’~for of mercury in Bellingham Bay .. .. ....... 45IiD Lead-ZlO. and polonium -ZlO. .. ............... ..... 46 E. Hydrocarbons in Lake...Biological oceanography, marine food chain dynamics, carbon cycling in the ocean. Martin, Seelye,Ph.D., Johns Hopkins. Geophysical fluid dynamics

  18. Who’s on First: Unraveling the Complexity of the United States’ Food and Agricultural Regulatory System in the Realm of Homeland Security

    Science.gov (United States)

    2009-12-01

    a weapon in food and water. The case involved the radiological poisoning of former Russian spy Alexander Litvinenko with Polonium 210 . An article... Polonium 210 an “extraordinary poison” that is lethal in doses so small “you can lose it on the point of a pin” (Jordan & Finn, 2006). Radiological agents...fundamentally new way” (Kim & Mauborgne, 2005, p. 210 ). What this implies in the movement toward a single food safety oversight system is that change

  19. Journal of Special Operations Medicine. Training Supplement to Fall 2008. Tactics, Techniques, and Procedures

    Science.gov (United States)

    2008-01-01

    suicide attacks may include the use of Sarin gas, Anthrax, or Polonium 210 . Incidental events such as the postal letter to Senator Daschle that...occurred in Washington, D.C. in October 2001 and the use of Polonium 210 against Alexander Litvinenko in November 2006 show the potential of future...the Food and Drug Administration (FDA) and proven to be effective in stopping life-threatening hemorrhage at the time of the publication of the

  20. Joint Force Quarterly. Issue 48, 1st Quarter 2008

    Science.gov (United States)

    2008-01-01

    in a London hospital in November 2006 due to ingested alpha particles from Polonium 210 . Just the trace trail of Polonium 210 across the city and...geted and killed 210 Palestinians. An additional 128 civilian bystanders were also killed during these operations. See <www.btselem.org/English...When the baby boomers were children, they passed signs every day for fallout shelters and stocks of water and food to be used in the event of a