WorldWideScience

Sample records for based radioactive decay

  1. Radioactive decay data tables

    Energy Technology Data Exchange (ETDEWEB)

    Kocher, D.C.

    1981-01-01

    The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and fusion reactor technology, and some of those of interest to Committee 2 of the International Commission on Radiological Protection for the estimation of annual limits on intake via inhalation and ingestion for occupationally exposed individuals.

  2. Is Radioactive Decay Really Exponential?

    CERN Document Server

    Aston, Philip J

    2012-01-01

    Radioactive decay of an unstable isotope is widely believed to be exponential. This view is supported by experiments on rapidly decaying isotopes but is more difficult to verify for slowly decaying isotopes. The decay of 14C can be calibrated over a period of 12,550 years by comparing radiocarbon dates with dates obtained from dendrochronology. It is well known that this approach shows that radiocarbon dates of over 3,000 years are in error, which is generally attributed to past variation in atmospheric levels of 14C. We note that predicted atmospheric variation (assuming exponential decay) does not agree with results from modelling, and that theoretical quantum mechanics does not predict exact exponential decay. We give mathematical arguments that non-exponential decay should be expected for slowly decaying isotopes and explore the consequences of non-exponential decay. We propose an experimental test of this prediction of non-exponential decay for 14C. If confirmed, a foundation stone of current dating meth...

  3. Progress and Validation of Geant4 Based Radioactive Decay Simulation Using the Examples of Simbol-X and IXO

    CERN Document Server

    Hauf, S; Pia, M G; Bell, Z; Briel, U; Chipaux, R; Hoffmann, D H H; Kendziorra, E; Laurent, P; Strüder, L; Tenzer, C; Weidenspointer, G; Zoglauer, A

    2009-01-01

    The anticipated high sensitivity and the science goals of the next generation X-ray space missions, like the International X-ray Observatory or Simbol-X, rely on a low instrumental background, which in turn requires optimized shielding concepts. We present Geant4 based simulation results on the IXO Wide Field Imager cosmic ray proton induced background in comparison with previous results obtained for the Simbol-X LED and HED focal plane detectors. Our results show that an improvement in mean differential background flux compared to actually operating X-ray observatories may be feasible with detectors based on DEPFET technology. In addition we present preliminary results concerning the validation of Geant4 based radioactive decay simulation in space applications as a part of the Nano5 project.

  4. Radioactive decay by the emission of heavy nuclear fragments

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, O.A.P.; Roberto, L.A.M.; Medeiros, E.L. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]. E-mails: oaptavares@cbpf.br; emil@cbpf.br

    2007-07-01

    Radioactive decay of nuclei by the emission of heavy ions of C, N, O, F, Ne, Na, Mg, Al, Si, and P isotopes (known as exotic decay or cluster radioactivity) is reinvestigated within the framework of a semiempirical, one-parameter model based on a quantum mechanical, tunnelling mechanism through a potential barrier, where both centrifugal and overlapping effects are considered to half-life evaluations. This treatment appeared to be very adequate at fitting all measured half-life values for the cluster emission cases observed to date. Predictions for new heavy-ion decay cases susceptible of being detected are also reported. (author)

  5. Nuclide radioactive decay data uncertainties library

    Science.gov (United States)

    Barabanova, D. S.; Zherdev, G. M.

    2017-01-01

    The results of the developing the library of uncertainties of radioactive decay data in the ABBN data library format are described. Different evaluations of uncertainties were compared and their effects on the results of calculations of residual energy release were determined using the test problems and experiment. Tables were generated in the ABBN format with the data obtained on the basis of libraries in ENDF-6 format. 3821 isotopes from the ENDF/B-7 data library, 3852 isotopes from the JEFF-3.11 data library and 1264 isotopes from the JENDL-4.0 data library were processed. It was revealed that the differences in the evaluations accepted in different decay data libraries are not so big, although they sometimes exceed the uncertainties assigned to the data in the ENDF/B-7 and JEFF-3.11 libraries, which as a rule, they agree with each other. On the basis of developed method it is supposed to create a library of data uncertainties for radioactive decay within the constant data system in FSUE RFNC-VNIIEF with its further connection with CRYSTAL module.

  6. Development of a New Method in Teaching of Physics Experiment : Simulation of Radioactive Decays

    OpenAIRE

    山下, 太利; 前田, 健悟; 桃井, 凡夫; ヤマシタ, タイリ; マエダ, ケンゴ; モモイ, ツネオ; Yamashita, Tairi; Maeda, Kengo; Momoi, Tsuneo

    1985-01-01

    The radioactive source used in the experiment of radioactive decay consists of the natural radioactive materials which are springing from the ground.This paper showed that the nuclides in the source were easily identified by the simulation of radioactive decays. Besides, it was also found that the simulation of radioactive series decays was useful for the students to understand the radioactive equilibrium.

  7. Radioactive decays at limits of nuclear stability

    DEFF Research Database (Denmark)

    Pfützner, M.; Karny, M.; Grigorenko, L. V.

    2012-01-01

    , and their relative probabilities. When approaching limits of nuclear stability, new decay modes set in. First, beta decays are accompanied by emission of nucleons from highly excited states of daughter nuclei. Second, when the nucleon separation energy becomes negative, nucleons start being emitted from the ground...

  8. Radioactive decays of highly-charged ions

    Directory of Open Access Journals (Sweden)

    Gao B. S.

    2015-01-01

    Full Text Available Access to stored and cooled highly-charged radionuclides offers unprecedented opportunities to perform high-precision investigations of their decays. Since the few-electron ions, e.g. hydrogen- or helium-like ions, are quantum mechanical systems with clear electronic ground state configurations, the decay studies of such ions are performed under well-defined conditions and allow for addressing fundamental aspects of the decay process. Presented here is a compact review of the relevant experiments conducted at the Experimental Storage Ring ESR of GSI. A particular emphasis is given to the investigations of the two-body beta decay, namely the bound-state β-decay and its time-mirrored counterpart, orbital electron-capture.

  9. Comprehensive decay law for emission of charged particles and exotic cluster radioactivity

    Indian Academy of Sciences (India)

    Basudeb Sahu

    2014-04-01

    A general decay formula for the emission of charged particles from metastable nuclei is developed based on the basic phenomenon of resonances occurring in quantum scattering process under Coulomb-nuclear potential. It relates the half-lives of radioactive decays with the values of the outgoing elements with masses and charges of the nuclei involved in the decay. The relation is found to be a generalization of the Geiger–Nuttall law in radioactivity and explains well all the known emissions of charged particles including clusters, alpha and proton.

  10. Radioactive decay as a forced nuclear chemical process: Phenomenology

    Science.gov (United States)

    Timashev, S. F.

    2015-11-01

    Concepts regarding the mechanism of radioactive decay of nuclei are developed on the basis of a hypothesis that there is a dynamic relationship between the electronic and nuclear subsystems of an atom, and that fluctuating initiating effects of the electronic subsystem on a nucleus are possible. Such relationship is reflected in experimental findings that show the radioactive decay of nuclei might be determined by a positive difference between the mass of an initial nucleus and the mass of an atom's electronic subsystem, i.e., the mass of the entire atom (rather than that of its nucleus) and the total mass of the decay products. It is established that an intermediate nucleus whose charge is lower by unity than the charge of the initial radioactive nucleus is formed as a result of the above fluctuating stimuli that initiate radioactive decay, and its nuclear matter is thus in an unbalanced metastable state of inner shakeup, affecting the quark subsystem of nucleons. The intermediate nucleus thus experiences radioactive decay with the emission of α or β particles. At the same time, the high energy (with respect to the chemical scale) of electrons in plasma served as a factor initiating the processes in different nuclear chemical transformations and radioactive decays in low-temperature plasma studied earlier, particularly during the laser ablation of metals in aqueous solutions of different compositions and in near-surface cathode layers upon glow discharge. It is shown that a wide variety of nucleosynthesis processes in the Universe can be understood on the same basis, and a great many questions regarding the formation of light elements in the solar atmosphere and some heavy elements (particularly p-nuclei) in the interiors of massive stars at late stages of their evolution can also be resolved.

  11. Digital signal processing for radioactive decay studies

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.; Madurga, M.; Paulauskas, S. V. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Ackermann, D.; Heinz, S.; Hessberger, F. P.; Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64220, Darmstadt (Germany); Grzywacz, R. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Miernik, K.; Rykaczewski, K. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Tan, H. [XIA LLC, Hayward, CA 94544 (United States)

    2011-11-30

    The use of digital acquisition system has been instrumental in the investigation of proton and alpha emitting nuclei. Recent developments extend the sensitivity and breadth of the application. The digital signal processing capabilities, used predominately by UT/ORNL for decay studies, include digitizers with decreased dead time, increased sampling rates, and new innovative firmware. Digital techniques and these improvements are furthermore applicable to a range of detector systems. Improvements in experimental sensitivity for alpha and beta-delayed neutron emitters measurements as well as the next generation of superheavy experiments are discussed.

  12. Simulations of Radioactive Decays: an Application of Low-Energy Electromagnetic Packages for the Nuclear Medicine

    Directory of Open Access Journals (Sweden)

    Munkhbaatar Batmunkh

    2015-12-01

    Full Text Available Problems of the radiobiology and the nuclear medicine require clarifying the specifi cs of radionuclides interactions with unhealthy cells. In this work we aimed to simulate emitting particles tracks of radionuclides and their radioactive decays at DNA level inside the cell nucleus. Accordingly, using the Monte Carlo-based track structure simulation technique, we estimated the radial distribution of deposited energy and kinetic energy spectra of electrons produced by primary particles resulting from radioactive decays of diff erent radionuclides within cell nucleus. To address the possibility of DNA damage, we performed the cluster analysis of track structures of emitted particles inside the volumes corresponding to the size of the native double-stranded DNA. For this purpose, G4-RadioactiveDecay and low- energy electromagnetic packages form Geant4 Monte-Carlo toolkit were combined together. Besides, a comparative analysis was performed for various low-energy electromagnetic packages as G4-DNA and G4-Livermore

  13. Metastable Dark Energy with Radioactive-like Decay

    CERN Document Server

    Shafieloo, Arman; Sahni, Varun; Starobinsky, Alexei A

    2016-01-01

    We propose a new class of metastable dark energy (DE) models in which the DE decay rate does not depend on external parameters such as the scale factor or the curvature of the Universe. Instead, the DE decay rate is a function only of the intrinsic properties of DE and, in this sense, resembles the radioactive decay of particles and nuclei. As a consequence, the DE energy density becomes a function of the proper time elapsed since its formation, presumably in the very early Universe. Such a natural type of DE decay can profoundly affect the expansion history of the Universe and its age. Metastable DE can decay in three distinct ways: (i) exponentially, (ii) into dark matter, (iii) into dark radiation. Testing metastable DE models with observational data we find that the decay half-life must be larger than the age of the Universe. Models in which dark energy decays into dark matter lead to lower values of the Hubble parameter at large redshifts relative to $\\Lambda$CDM. Consequently these models provide a bett...

  14. Unified formula of half-lives for α decay and cluster radioactivity

    Science.gov (United States)

    Ni, Dongdong; Ren, Zhongzhou; Dong, Tiekuang; Xu, Chang

    2008-10-01

    In view of the fact that α decay and cluster radioactivity are physically analogical processes, we propose a general formula of half-lives and decay energies for α decay and cluster radioactivity. This new formula is directly deduced from the WKB barrier penetration probability with some approximations. It is not only simple in form and easy to see the physical meanings but also shows excellent agreement with the experimental values. Moreover, the difference between two sets of parameters to separately describe α decay and cluster radioactivity is small. Therefore, we use only one set of adjustable parameters to simultaneously describe the α decay and cluster radioactivity data for even-even nuclei. The results are also satisfactory. This indicates that this formula successfully combines the phenomenological laws of α decay and cluster radioactivity. We expect it to be a significant step toward a unified phenomenological law of α decay and cluster radioactivity.

  15. An Accelerated Radioactive Decay (ARD) Model for Type Ia Supernovae

    Science.gov (United States)

    Rust, Bert W.; Leventhal, Marvin

    2016-01-01

    In 1975, Leventhal and McCall [Nature, 255, 690-692] presented a radioactive decay model 56N i --> 56Co --> 56Fe for the post-peak luminosity decay of Type I supernovae light curves, in which the two decay rates are both accelerated by a common factor. In 1976, Rust, Leventhal and McCall [Nature, 262, 118-120] used sums of exponentials fitting to confirm the acceleration hypothesis, but their result was nevertheless rejected by the astronomical community. Here, we model Type Ia light curves with a system of ODEs (describing the nuclear decays) forced by a Ni-deposition pulse modelled by a 3-parameter Weibull pdf, with all of this occuring in the center of a pre-existing, optically thick, spherical shell which thermalizes the emitted gamma rays. Fitting this model to observed light curves routinely gives fits which account for 99.9+% of the total variance in the observed record. The accelerated decay rates are so stable, for such a long time, that they must occur in an almost unchanging environment -- not it a turbulent expanding atmosphere. The amplitude of the Ni-deposition pulse indicates that its source is the fusion of hydrogen. Carbon and oxygen could not supply the large energy/nucleon that is observed. The secondary peak in the infrared light curve can be easily modelled as a light echo from dust in the back side of the pre-existing shell, and the separation between the peaks indicates a radius of ≈15 light days for the shell. The long-term stability of the acceleration suggests that it is a kinematic effect arising because the nuclear reactions occur either on the surface of a very rapidly rotating condensed object, or in a very tight orbit around such an object, like the fusion pulse in a tokomak reactor.

  16. User`s manual for the radioactive decay and accumulation code RADAC

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, R.; Loghry, S.L.; Ashline, R.C.

    1995-11-01

    The RADAC computer code calculates radioactive decay and accumulation of decayed products using an algorithm based on the direct use of the Bateman equations and referred to here as the yield factor method. This report explains the yield factor method, gives an overview of the various modules in the RADAC code system, and describes the decay and accumulation code in detail. The RADAC code has capacity for two waste types and can accommodate up to 60 years of annual waste inputs. Decay times as high as 1 million years can be calculated. The user supplies the undecayed composition and radioactivity of the waste placed in storage each year. The code calculates the decayed composition, radioactivity, and thermal power of the accumulated waste at the end of each year and gives the results in terms of grams and curies of individual radionuclides. Calculations can be made for up to 19 waste storage sites in a single run. For each site and each waste type, calculations can be made by 1-year steps up to 60 years, by 10-year steps to 160 years, and by 6 discrete steps to 1 million years. Detailed outputs can be printed for each waste site and each time step by individual radionuclides. Summarized outputs are also available. Excluding data-preparation time, RADAC requires about 2 min to run 19 waste sites with two types of transuranic waste at each site, using a 486 DX computer with a clock speed of 33 MHz. Because RADAC uses a preselected set of decay times and does not make in-reactor calculations, it should not be viewed as a substitute for ORIGEN2. RADAC is intended for use in applications in which accumulations at the decay times provided by the code are sufficient for the user`s purposes.

  17. Kinetics analysis and quantitative calculations for the successive radioactive decay process

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Zhiping, E-mail: zhouzp@ujs.edu.cn [School of Materials Science and Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Yan, Deyue [School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Zhao, Yuliang; Chai, Zhifang [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2015-01-15

    The general radioactive decay kinetics equations with branching were developed and the analytical solutions were derived by Laplace transform method. The time dependence of all the nuclide concentrations can be easily obtained by applying the equations to any known radioactive decay series. Taking the example of thorium radioactive decay series, the concentration evolution over time of various nuclide members in the family has been given by the quantitative numerical calculations with a computer. The method can be applied to the quantitative prediction and analysis for the daughter nuclides in the successive decay with branching of the complicated radioactive processes, such as the natural radioactive decay series, nuclear reactor, nuclear waste disposal, nuclear spallation, synthesis and identification of superheavy nuclides, radioactive ion beam physics and chemistry, etc.

  18. Kinetics analysis and quantitative calculations for the successive radioactive decay process

    Science.gov (United States)

    Zhou, Zhiping; Yan, Deyue; Zhao, Yuliang; Chai, Zhifang

    2015-01-01

    The general radioactive decay kinetics equations with branching were developed and the analytical solutions were derived by Laplace transform method. The time dependence of all the nuclide concentrations can be easily obtained by applying the equations to any known radioactive decay series. Taking the example of thorium radioactive decay series, the concentration evolution over time of various nuclide members in the family has been given by the quantitative numerical calculations with a computer. The method can be applied to the quantitative prediction and analysis for the daughter nuclides in the successive decay with branching of the complicated radioactive processes, such as the natural radioactive decay series, nuclear reactor, nuclear waste disposal, nuclear spallation, synthesis and identification of superheavy nuclides, radioactive ion beam physics and chemistry, etc.

  19. Electroweak Decay Studies of Highly Charged Radioactive Ions with TITAN at TRIUMF

    CERN Document Server

    Leach, K G; Klawitter, R; Leistenschneider, E; Lennarz, A; Brunner, T; Frekers, D; Andreiou, C; Kwiatkowski, A A; Dilling, J

    2016-01-01

    Several modes of electroweak radioactive decay require an interaction between the nucleus and bound electrons within the constituent atom. Thus, the probabilities of the respective decays are not only influenced by the structure of the initial and final states in the nucleus, but can also depend strongly on the atomic charge. Conditions suitable for the partial or complete ionization of these rare isotopes occur naturally in hot, dense astrophysical environments, but can also be artificially generated in the laboratory to selectively block certain radioactive decay modes. Direct experimental studies on such scenarios are extremely difficult due to the laboratory conditions required to generate and store radioactive ions at high charge states. A new electron-beam ion trap (EBIT) decay setup with the TITAN experiment at TRIUMF has successfully demonstrated such techniques for performing spectroscopy on the radioactive decay of highly charged ions.

  20. Competition between α decay and proton radioactivity of neutron-deficient nuclei

    Science.gov (United States)

    Wang, Y. Z.; Cui, J. P.; Zhang, Y. L.; Zhang, S.; Gu, J. Z.

    2017-01-01

    The α decay and proton radioactivity half-lives of some neutron-deficient nuclei are calculated using an effective liquid drop model (ELDM). It is found that the experimental half-lives of the two decay modes and the dominant decay mode can be well reproduced by the ELDM. Moreover, the predicted penetration probabilities (P ) of proton radioactivity by the ELDM are in agreement with those by a microscopic model (MM). This allows us to make predictions on the competition of the two decay modes for nuclei whose experimental data are not available, which are useful for future measurements. In addition, the comparison between the predicted reduced proton radioactivity half-lives by the ELDM and the ones by a standard formula suggests that one is unlikely to observe large angular momentum transfers for nuclei with a very large Coulomb parameter χ . Last, we find that in most isotope chains the proton radioactivity is the dominant decay mode for nuclei that are very close to the proton drip line. But with increasing neutron number N the main decay mode is changed into α decay. With the decay energies the decay mode anomaly of 184Bi is discussed.

  1. The light curve in supernova modeled by a continuous radioactive decay of $^{56}$Ni

    CERN Document Server

    Zaninetti, L

    2014-01-01

    The UVOIR bolometric light curves are usually modeled by the radioactive decay. In order to model more precisely the absolute/apparent magnitude versus time relationship the continuous production of radioactive isotopes is introduced. A differential equation of the first order with separable variables is solved.

  2. Cluster emission in the radioactive decay of 223Ac

    CERN Document Server

    Steyn, G F; Faccio, D; Bonetti, R; Tretyakova, S P; Shishkin, S V; Ogloblin, A A; Pik-Pichak, G A; Vermeulen, C; van der Meulen, N P; van der Walt, T N; McGee, D

    2010-01-01

    The branching ratio of 223Ac decay by spontaneous 14C emission was measured and a search for 15N clusters was performed. After exposure of a hemispherical array of solid-state nuclear track detectors, 347 14C events were identified and no 15N events. B(14C) = λ(14C)/λ(α) = (3.2 ± 1.0) x 10-11 is consistent with a favoured ground state to ground state transition. As no nitrogen tracks were found, only an upper limit could be inferred for 15N emission, B(15N) = λ(15N)/λ(α) ≤ 2.2 x 10-13 (confidence limit 90%), consistent with an unfavoured transition. Intense 227Pa sources were produced for this study, using the reaction 232Th(p,6n)227Pa. This offered an opportunity to compare the measured source strength with predictions based on published excitation function data.

  3. New experimental data on the influence of extranuclear factors on the probability of radioactive decay

    CERN Document Server

    Bondarevskij, S I; Skorobogatov, G A

    2002-01-01

    New experimental data on influence of various extranuclear factors on probability (lambda) of radioactive decay are presented. During redox processes in solutions containing sup 1 sup 3 sup 9 Ce relative change in lambda measured by the DELTA I/I method was [I(Ce sup I sup V)-I(Ce sup I sup I sup I)]/I sub m sub e sub a sub n +(1.4+-0.6)x10 sup - sup 4. Using a modification of the method based on displacement of the age-old radioactive equilibrium, when a source MgO( sup 1 sup 2 sup 1 sup m Te) was cooled to 78 K, growth of lambda of tellurium nuclear isomer by 0.04+-0.02% was detected. New experimental data on increase in gamma-radioactivity of sample Be sup 1 sup 2 sup 3 sup m Te at the expense of low-temperature induced reaction, i.e. collective nuclear superluminescence, are provided

  4. Theory of cluster radioactive decay and of cluster formation in nuclei

    Science.gov (United States)

    Malik, S. S.; Gupta, Raj K.

    1989-05-01

    A new model is proposed for the mechanism of cluster formation and then penetration of the confining nuclear interaction barrier in radioactive nuclei. The cluster formation is treated as a quantum-mechanical fragmentation process and the WKB penetrability is found analytically. Applications of the model are made to 14C decay of 222-224Ra and 24Ne decay of 232U. The branching ratio for 14C decay of 232U is also calculated and is found to be incredibly small as compared to that for its 24Ne decay.

  5. Cold valleys in the radioactive decay of 248-254Cf isotopes

    Indian Academy of Sciences (India)

    R K Biju; Sabina Sahadevan; K P Santosh; Antony Joseph

    2008-04-01

    Based on the concept of cold valley in cold fission and fusion, we have investigated the cluster decay process in 248-254Cf isotopes. In addition to alpha particle minima, other deep minima occur for S, Ar and Ca clusters. It is found that inclusion of proximity potential does not change the position of minima but minima become deeper. Taking Coulomb and proximity potential as interacting barrier for post-scission region, we computed half-lives and other characteristics for various clusters from these parents. Our study reveals that these parents are stable against light clusters and unstable against heavy clusters. Computed half-lives for alpha decay agree with experimental values within two orders of magnitude. The most probable clusters from these parents are predicted to be 46Ar, 48,50Ca which indicate the role of doubly or near doubly magic clusters in cluster radioactivity. Odd A clusters are found to be favorable for emission from odd A parents. Cluster decay model is extended to symmetric region and it is found that symmetric fission is also probable which stresses the role of doubly or near doubly magic 132Sn nuclei. Geiger-Nuttal plots were studied for various clusters and are found to be linear with varying slopes and intercepts.

  6. An Amended Formula for the Decay of Radioactive Material for Cosmic Times

    CERN Document Server

    Carmeli, M; Carmeli, Moshe; Malin, Shimon

    1999-01-01

    An amended formula for the decay of radioactive material is presented. It is a modification of the standard exponential formula. The new formula applies for long cosmic times that are comparable to the Hubble time. It reduces to the standard formula for short times. It is shown that the material decays faster than expected. The application of the new formula to direct measurements of the age of the Universe and its implications is briefly discussed.

  7. Comment on ``Interpretation of the fine structure in the 14C radioactive decay of 223'

    Science.gov (United States)

    Hussonnois, M.; Le Du, J. F.; Brillard, L.; Ardisson, G.

    1991-12-01

    Priority of our interpretation of the fine structure in the 14C radioactive decay of 223Ra is asserted. It seems that the deformation parameter values, used in the framework of ARM to interpret properties of both 223Ra ground and excited states, partly allow for the qualitative interpretation of the experimental hindrance factors to the 209Pb states.

  8. Description of alpha decay and cluster radioactivity in the dinuclear system model

    Science.gov (United States)

    Kuklin, S. N.; Adamian, G. G.; Antonenko, N. V.

    2016-03-01

    A unified description of cluster radioactivity and α-decay of cold nuclei in the dinuclear system model is proposed. Quantum dynamical fluctuations along the charge (mass) asymmetry coordinate determine the spectroscopic factor, and tunneling along the relative distance coordinate determines the penetrability of the barrier of the nucleus-nucleus interaction potential. A new method for calculating the spectroscopic factor is proposed. The hindrance factors for the orbital angular momentum transfer are studied. A potential reason for the half-life to deviate from the Geiger-Nuttall law in α-decays of neutron-deficient nuclei 194, 196Rn is found. The fine structure of α-decays of U and Th isotopes is predicted and characterized. The model is used to describe α-decays from the rotational band of even-even nuclei. The known half-lives in the regions of "lead" and "tin" radioactivities are reproduced well, and the most probable cluster yields are predicted. The cluster decay of excited nuclei is discussed. The relation of cluster radioactivity to spontaneous fission and highly deformed nuclear states is analyzed.

  9. Radioactive decay products in neutron star merger ejecta: heating efficiency and $\\gamma$-ray emission

    CERN Document Server

    Hotokezaka, Kenta; Tanaka, Masaomi; Bamba, Aya; Terada, Yukikatsu; Piran, Tsvi

    2015-01-01

    The radioactive decay of the freshly synthesized $r$-process nuclei ejected in compact binary mergers power optical/infrared macronovae (kilonovae) that follow these events. The light curves depend critically on the energy partition among the different products of the radioactive decay and this plays an important role in estimates of the amount of ejected $r$-process elements from a given observed signal. We study the energy partition and $\\gamma$-ray emission of the radioactive decay. We show that $20$-$50\\%$ of the total radioactive energy is released in $\\gamma$-rays on timescales from hours to a month. The number of emitted $\\gamma$-rays per unit energy interval has roughly a flat spectrum between a few dozen keV and $1$ MeV so that most of this energy is carried by $\\sim 1$ MeV $\\gamma$-rays. However at the peak of macronova emission the optical depth of the $\\gamma$-rays is $\\sim 0.02$ and most of the $\\gamma$-rays escape. The loss of these $\\gamma$-rays reduces the heat deposition into the ejecta and h...

  10. Determination of the isomeric fraction in a postaccelerated radioactive ion beam using the coupled decay-chain equations

    CERN Document Server

    Ekstrom, A; Dijulio, D D; Cederkall, J; Van de Walle, J

    2010-01-01

    A method based on the coupled decay-chain equations for extracting the isotopic and the isomeric composition of a postaccelerated radioactive ion beam is presented and demonstrated on a data set from a Coulomb excitation experiment. This is the first attempt of analyzing the content of a postaccelerated radioactive ion beam using this technique. The beam composition is required for an absolute normalization of the measurement. The strength of the method, as compared to present online-based methods, lies in the determination of the isomeric fraction of a partially isomeric beam using all data accumulated during the experiment. We discuss the limitations and sensitivity of the method with respect to the gamma-ray detection efficiency and the accumulated flux. (C) 2010 Elsevier B.V. All rights reserved.

  11. Asymptotic Analysis of Time-Dependent Neutron Transport Coupled with Isotopic Depletion and Radioactive Decay

    Energy Technology Data Exchange (ETDEWEB)

    Brantley, P S

    2006-09-27

    We describe an asymptotic analysis of the coupled nonlinear system of equations describing time-dependent three-dimensional monoenergetic neutron transport and isotopic depletion and radioactive decay. The classic asymptotic diffusion scaling of Larsen and Keller [1], along with a consistent small scaling of the terms describing the radioactive decay of isotopes, is applied to this coupled nonlinear system of equations in a medium of specified initial isotopic composition. The analysis demonstrates that to leading order the neutron transport equation limits to the standard time-dependent neutron diffusion equation with macroscopic cross sections whose number densities are determined by the standard system of ordinary differential equations, the so-called Bateman equations, describing the temporal evolution of the nuclide number densities.

  12. DCHAIN: A user-friendly computer program for radioactive decay and reaction chain calculations

    Energy Technology Data Exchange (ETDEWEB)

    East, L.V.

    1994-05-01

    A computer program for calculating the time-dependent daughter populations in radioactive decay and nuclear reaction chains is described. Chain members can have non-zero initial populations and be produced from the preceding chain member as the result of radioactive decay, a nuclear reaction, or both. As presently implemented, chains can contain up to 15 members. Program input can be supplied interactively or read from ASCII data files. Time units for half-lives, etc. can be specified during data entry. Input values are verified and can be modified if necessary, before used in calculations. Output results can be saved in ASCII files in a format suitable for including in reports or other documents. The calculational method, described in some detail, utilizes a generalized form of the Bateman equations. The program is written in the C language in conformance with current ANSI standards and can be used on multiple hardware platforms.

  13. Abnormal Radioactive Decays out of Long-Lived Super- and Hyper-Deformed Isomeric States

    CERN Document Server

    Marinov, A; Kolb, D

    2000-01-01

    Long-lived high-spin super- and hyper-deformed isomeric states, which exhibit themselves by abnormal radioactive decays, have been observed using the 16O + 197Au and 28Si + 181Ta reactions. They make it possible to understand the production, via secondary reactions, of the long-lived superheavy element with Z = 112 and of the abnormally low energy and very enhanced alpha-particles seen in various actinide sources. They may also explain some puzzling phenomena seen in nature.

  14. Wait for it: Post-supernova winds driven by delayed radioactive decays

    CERN Document Server

    Shen, Ken J

    2016-01-01

    In most astrophysical situations, the radioactive decay of 56Ni to 56Co occurs via electron capture with a fixed half-life of 6.1 days. However, this decay rate is significantly slowed when the nuclei are fully ionized because K-shell electrons are unavailable for capture. In this paper, we explore the effect of these delayed decays on white dwarfs (WDs) that may survive Type Ia and Type Iax supernovae (SNe Ia and SNe Iax). The energy released by the delayed radioactive decays of 56Ni and 56Co drives a persistent wind from the surviving WD's surface that contributes to the late-time appearance of these SNe after emission from the bulk of the SN ejecta has faded. We use the stellar evolution code MESA to calculate the hydrodynamical evolution and resulting light curves of these winds. Our post-SN Ia models conflict with late-time observations of SN 2011fe, but uncertainties in our initial conditions prevent us from ruling out the existence of surviving WD donors. Much better agreement with observations is achi...

  15. Simulation of decay processes and radiation transport times in radioactivity measurements

    Science.gov (United States)

    García-Toraño, E.; Peyres, V.; Bé, M.-M.; Dulieu, C.; Lépy, M.-C.; Salvat, F.

    2017-04-01

    The Fortran subroutine package PENNUC, which simulates random decay pathways of radioactive nuclides, is described. The decay scheme of the active nuclide is obtained from the NUCLEIDE database, whose web application has been complemented with the option of exporting nuclear decay data (possible nuclear transitions, branching ratios, type and energy of emitted particles) in a format that is readable by the simulation subroutines. In the case of beta emitters, the initial energy of the electron or positron is sampled from the theoretical Fermi spectrum. De-excitation of the atomic electron cloud following electron capture and internal conversion is described using transition probabilities from the LLNL Evaluated Atomic Data Library and empirical or calculated energies of released X rays and Auger electrons. The time evolution of radiation showers is determined by considering the lifetimes of nuclear and atomic levels, as well as radiation propagation times. Although PENNUC is designed to operate independently, here it is used in conjunction with the electron-photon transport code PENELOPE, and both together allow the simulation of experiments with radioactive sources in complex material structures consisting of homogeneous bodies limited by quadric surfaces. The reliability of these simulation tools is demonstrated through comparisons of simulated and measured energy spectra from radionuclides with complex multi-gamma spectra, nuclides with metastable levels in their decay pathways, nuclides with two daughters, and beta plus emitters.

  16. Entrance channel effect with stable and radioactive beams using dynamical cluster decay model

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Raj, E-mail: rajkumarfzr@gmail.com [Dipartimento di Fisica “Galileo Galilei” and INFN, University of Padova, Padova-35131 (Italy); Jain, Deepika [School of Physics and Material Science, Thapar University, Patiala-147004 (India)

    2014-09-15

    The decay of hot and rotating {sup 172}Yb*, formed in two entrance channels {sup 124}Sn + {sup 48}Ca and {sup 132}Sn + {sup 40}Ca, is studied using the dynamical cluster-decay model. The effect of entrance channel, deformations (up to β{sub 2}), barrier modification and fusion enhancement are addressed. The decay pattern of compound system, formed in different channels at comparable energy around the barrier, shows change in magnitude with structure remains almost same. There is an increase in the fusion probability with decrease in barrier modification, which leads to fusion enhancement at low energies. The higher ℓ values are contributing for {sup 132}Sn + {sup 40}Ca channel at lower energies as compare to {sup 124}Sn + {sup 48}Ca. It is inferred that with the use of stable and radioactive beam, forming same compound nucleus, the entrance channel dependence changes with the excitation energy.

  17. Wait for It: Post-supernova Winds Driven by Delayed Radioactive Decays

    Science.gov (United States)

    Shen, Ken J.; Schwab, Josiah

    2017-01-01

    In most astrophysical situations, the radioactive decay of {}56{Ni} to {}56{Co} occurs via electron capture with a fixed half-life of 6.1 days. However, this decay rate is significantly slowed when the nuclei are fully ionized because K-shell electrons are unavailable for capture. In this paper, we explore the effect of these delayed decays on white dwarfs (WDs) that may survive Type Ia and Type Iax supernovae (SNe Ia and SNe Iax). The energy released by the delayed radioactive decays of {}56{Ni} and {}56{Co} drives a persistent wind from the surviving WD’s surface that contributes to the late-time appearance of these SNe after emission from the bulk of the SN ejecta has faded. We use the stellar evolution code MESA to calculate the hydrodynamic evolution and resulting light curves of these winds. Our post-SN Ia models conflict with late-time observations of SN 2011fe, but uncertainties in our initial conditions prevent us from ruling out the existence of surviving WD donors. Much better agreement with observations is achieved with our models of post-SN Iax bound remnants, providing evidence that these explosions are due to deflagrations in accreting WDs that fail to completely unbind the WDs. Future radiative transfer calculations and wind models utilizing simulations of explosions for more accurate initial conditions will extend our study of radioactively powered winds from post-SN surviving WDs and enable their use as powerful discriminants among the various SN Ia and SN Iax progenitor scenarios.

  18. LEAF: a computer program to calculate fission product release from a reactor containment building for arbitrary radioactive decay chains

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.E.; Apperson, C.E. Jr.; Foley, J.E.

    1976-10-01

    The report describes an analytic containment building model that is used for calculating the leakage into the environment of each isotope of an arbitrary radioactive decay chain. The model accounts for the source, the buildup, the decay, the cleanup, and the leakage of isotopes that are gas-borne inside the containment building.

  19. Multi-day radon signals with a radioactive decay limb-Occurrence and geophysical significance

    Energy Technology Data Exchange (ETDEWEB)

    Steinitz, G. [Geological Survey of Israel, Jerusalem (Israel)]. E-mail: steinitz@mail.gsi.gov.il; Martin, M.C. [University of La Laguna, La Laguna, Tenerife (Spain); Gazit-Yaari, N. [Geological Survey of Israel, Jerusalem (Israel); Quesada, M.L. [University of La Laguna, La Laguna, Tenerife (Spain); Nuez, J. de la [University of La Laguna, La Laguna, Tenerife (Spain); Casillas, R. [University of La Laguna, La Laguna, Tenerife (Spain); Malik, U. [Geological Survey of Israel, Jerusalem (Israel); Begin, Z.B. [Geological Survey of Israel, Jerusalem (Israel)

    2006-04-15

    Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geo gas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes.

  20. Multi-day radon signals with a radioactive decay limb -- occurrence and geophysical significance.

    Science.gov (United States)

    Steinitz, G; Martín, M C; Gazit-Yaari, N; Quesada, M L; de la Nuez, J; Casillas, R; Malik, U; Begin, Z B

    2006-04-01

    Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geogas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn, (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes.

  1. Induced radioactivity in the target station and decay tunnel from a 4MW proton beam

    CERN Document Server

    Agosteo, S; Otto, T; Silari, Marco

    2003-01-01

    An important aspect of a future CERN Neutrino Factory is the material activation arising from a 2.2 GeV, 4 MW proton beam striking a mercury target. A first estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump has been performed by the Monte Carlo hadronic cascade code FLUKA. The aim is both to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which will have to be disposed of after the facility has ceased operation. This paper discusses the first results of such calculations.

  2. Characteristics of spent fuel, high-level waste, and other radioactive wastes which may require long-term isolation: Appendix 3A, ORIGEN2 decay tables for immobilized high-level waste, Appendix 3B, Interim high-level waste forms, Appendix 3C, User's guide to the high-level waste PC data base

    Energy Technology Data Exchange (ETDEWEB)

    1987-12-01

    The purpose of this report, and the information contained in the associated computerized data bases, is to establish the DOE/OCRWM reference characteristics of the radioactive waste materials that may be accepted by DOE for emplacement in he mined geologic disposal system. This report provides relevant technical data for use by DOE and its supporting contractors and is not intended to be a policy document. This document is backed up by five PC-compatible data bases, written in a user-oriented, menu-driven format, which were developed for this purpose. The data bases are the LWR Assemblies Data Base; the LWR Radiological Data Base; the LWR Quantities Data Base; the LWR NFA Hardware Data Base; and the High-Level Waste Data Base. The above data bases may be ordered using the included form. Volume 6 contains decay tables for immobilized high-level waste, information on interim high-level waste forms, and a user's guide to the high-level waste PC data base.

  3. An Improved Method of Lifetime Measurement of Nuclei in Radioactive Decay Chain

    CERN Document Server

    Puzović, J M; Nađđerđ, L J

    2016-01-01

    We present an improved statistical method for calculation of mean lifetime of nuclei in a decay chain with uncertain relation between mother and daughter nuclei. The method is based on formation of time distribution of intervals between mother and daughter nuclei, without trying to set the exact mother-daughter nuclei relationship. If there is a coincidence of mother and daughter nuclei decays, sum of these distributions has flat term on which an exponential term is superimposed. Parameters of this exponential function allow lifetime of daughter nucleus to be extracted. The method is tested on Monte Carlo simulation data.

  4. An improved method of lifetime measurement of nuclei in radioactive decay chain

    Science.gov (United States)

    Puzović, J. M.; Manić, D.; Nađđerđ, L. J.

    2017-04-01

    We present an improved statistical method for the calculation of mean lifetime of nuclei in a decay chain with an uncertain relation between mother and daughter nuclei. The method is based on the formation of time distribution of intervals between mother and daughter nuclei, without trying to set the exact mother-daughter nuclei relationship. If there is a coincidence of mother and daughter nuclei decays, the sum of these distributions has flat term on which an exponential term is superimposed. Parameters of this exponential function allow lifetime of daughter nucleus to be extracted. The method is tested on Monte Carlo simulation data.

  5. A computer code for calculation of radioactive nuclide generation and depletion, decay heat and {gamma} ray spectrum. FPGS90

    Energy Technology Data Exchange (ETDEWEB)

    Ihara, Hitoshi; Katakura, Jun-ichi; Nakagawa, Tsuneo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1995-11-01

    In a nuclear reactor radioactive nuclides are generated and depleted with burning up of nuclear fuel. The radioactive nuclides, emitting {gamma} ray and {beta} ray, play role of radioactive source of decay heat in a reactor and radiation exposure. In safety evaluation of nuclear reactor and nuclear fuel cycle, it is needed to estimate the number of nuclides generated in nuclear fuel under various burn-up condition of many kinds of nuclear fuel used in a nuclear reactor. FPGS90 is a code calculating the number of nuclides, decay heat and spectrum of emitted {gamma} ray from fission products produced in a nuclear fuel under the various kinds of burn-up condition. The nuclear data library used in FPGS90 code is the library `JNDC Nuclear Data Library of Fission Products - second version -`, which is compiled by working group of Japanese Nuclear Data Committee for evaluating decay heat in a reactor. The code has a function of processing a so-called evaluated nuclear data file such as ENDF/B, JENDL, ENSDF and so on. It also has a function of making figures of calculated results. Using FPGS90 code it is possible to do all works from making library, calculating nuclide generation and decay heat through making figures of the calculated results. (author).

  6. Pulsational Pair-instability Model for Superluminous Supernova PTF12dam: Interaction and Radioactive Decay

    Science.gov (United States)

    Tolstov, Alexey; Nomoto, Ken’ichi; Blinnikov, Sergei; Sorokina, Elena; Quimby, Robert; Baklanov, Petr

    2017-02-01

    Being a superluminous supernova, PTF12dam can be explained by a 56Ni-powered model, a magnetar-powered model, or an interaction model. We propose that PTF12dam is a pulsational pair-instability supernova, where the outer envelope of a progenitor is ejected during the pulsations. Thus, it is powered by a double energy source: radioactive decay of 56Ni and a radiative shock in a dense circumstellar medium. To describe multicolor light curves and spectra, we use radiation-hydrodynamics calculations of the STELLA code. We found that light curves are well described in the model with 40 M⊙ ejecta and 20–40 M⊙ circumstellar medium. The ejected 56Ni mass is about 6 M⊙, which results from explosive nucleosynthesis with large explosion energy (2–3) × 1052 erg. In comparison with alternative scenarios of pair-instability supernova and magnetar-powered supernova, in the interaction model, all the observed main photometric characteristics are well reproduced: multicolor light curves, color temperatures, and photospheric velocities.

  7. Cold reaction valleys in the radioactive decay of superheavy {286}^112, {292}^114 and {296}^116 nuclei

    CERN Document Server

    Santhosh, K P

    2012-01-01

    Cold reaction valleys in the radioactive decay of superheavy nuclei {286}^112, {292}^114 and {296}^116 are studied taking Coulomb and Proximity Potential as the interacting barrier. It is found that in addition to alpha particle, 8^Be, 14^C, 28^Mg, 34^Si, 50^Ca, etc. are optimal cases of cluster radioactivity since they lie in the cold valleys. Two other regions of deep minima centered on 208^Pb and 132^Sn are also found. Within our Coulomb and Proximity Potential Model half-life times and other characteristics such as barrier penetrability, decay constant for clusters ranging from alpha particle to 68^Ni are calculated. The computed alpha half-lives match with the values calculated using Viola--Seaborg--Sobiczewski systematics. The clusters 8^Be and 14^C are found to be most probable for emission with T_1/2 < 1030s. The alpha-decay chains of the three superheavy nuclei are also studied. The computed alpha decay half-lives are compared with the values predicted by Generalized Liquid Drop Model and they are...

  8. Half-lives for proton emission, alpha decay, cluster radioactivity, and cold fission processes calculated in a unified theoretical framework

    CERN Document Server

    Duarte, S B; Guzmán, F; Di Marco, A; García, F; Rodríguez, O; Gonçalves, M

    2002-01-01

    Half-life values of spontaneous nuclear decay processes are presented in the framework of the effective liquid drop model (ELDM) using the combination of varying mass asymmetry shape description for the mass transfer (VMAS) and Werner-Wheeler's inertia coefficient (WW). The calculated half lives of ground-state to ground-state transitions for proton emission, alpha decay, cluster radioactivity, and cold fission processes are compared with experimental data. These comparisons show that the ELDM is a very efficient model to describe these different decay processes in a same, unified, theoretical framework. A table listing the predicted half-life values, tau sub c , is presented for all possible cases of spontaneous nuclear breakup such that -7.30 -17.0, where tau is the total half life of the parent nucleus.

  9. Microscopic approach to the rates of radioactive decay by emission of heavy clusters

    Energy Technology Data Exchange (ETDEWEB)

    Ivascu, M.; Silisteanu, I.

    1988-08-08

    We have applied a simple microscopic decay theory to the analysis of the rare decay modes. The absolute decay rates are estimated by using the shell model and resonance formation factors and optical model penetrabilities. The resonance formation factors are deduced from the strong interaction form of the theory where the wave function in the internal region is represented in terms of compound nucleus decay. In order to account fully for the data, the implication of internal degrees of freedom was found to be necessary, but no adjustment of Gamow factor was needed. The results have been discussed in the light of the previously reported results and data.

  10. Late-Time Photometry of Type Ia Supernova SN2012cg Reveals the Radioactive Decay of $^{57}$Co

    CERN Document Server

    Graur, Or; Shara, Michael M; Riess, Adam G

    2015-01-01

    Seitenzahl et al. (2009) have predicted that $\\sim 3$ years after its explosion, the light we receive from a Type Ia supernova will come mostly from reprocessing of electrons and X-rays emitted by the radioactive decay chain $^{57}{\\rm Co}~\\to~^{57}{\\rm Fe}$, instead of positrons from the decay chain $^{56}{\\rm Co}~\\to~^{56}{\\rm Fe}$ that dominates the supernova light at earlier times. Using the Hubble Space Telescope, we followed the light curve of the Type Ia supernova SN2012cg out to $1055$ days after maximum light. Our measurements are consistent with the light curves predicted by the contribution of energy from the reprocessing of electrons and X-rays emitted by the decay of $^{57}$Co. This provides conclusive evidence that $^{57}$Co is produced in Type Ia supernova explosions. The ratio of luminosities produced by the decays of $^{57}$Co and $^{56}$Co, a strong constraint on any Type Ia supernova explosion model, is in the range $(0.4$ - $8.5)\\times10^{-3}$.

  11. Half-lives for proton emission, alpha decay, cluster radioactivity, and cold fission processes calculated in a unified theoretical framework

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, S.B.; Tavares, O.A.P.; Guzman, F.; Dimarco, A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Garcia, F. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Dept. de Ciencias Exatas e Tecnologicas; Rodriguez, O. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Instituto Superior de Ciencias e Tecnologia Nucleares, La Habana (Cuba); Goncalves, M. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil)

    2002-01-01

    Half-life values of spontaneous nuclear decay processes are presented in the framework of the Effective Liquid Drop Model (ELDM) using the combination of varying mass asymmetry shape description for the mass transfer with Werner-Wheeler's inertia coefficient V{sub MAS}/WW. The calculated half-lives of ground-state to ground-state transitions for the proton emission, alpha decay, cluster radioactivity, and cold fission processes are compared with experimental data. Results have shown that the ELDM is a very efficient model to describe these different decay processes in a same, unified theoretical framework. A Table listing the predicted half-life values, {tau}{sub c} is presented for all possible cases of spontaneous nuclear break-up such that -7.30 <{approx_equal} log{sub 10} {tau}{sub c} [S] <{approx_equal} 27.50 and log {sub 10}({tau}/{tau}{sub c}) > -17.0, where {tau} is the total half-life of the parent nucleus. (author)

  12. Changes of decay rates of radioactive 111In and 32P induced by mechanic motion

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The changes of decay rates of radionuclide 111In(electron capture) and 32P(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2000 r/min) ,the half life of 111In compared with the referred(2.83 d) is decreased at 2.83% and increased at 1.77%,respectively;the half life of 32P compared with the referred(14.29 d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.31% and increased at 6.36%,respectively;the half life of 32P is decreased at 10.08% and increased at 4.34%,respectively. When the circular rotation is removed,the decay rates of 111In and 32P return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 32P,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

  13. LWR decay heat calculations using a GRS improved ENDF/B-6 based ORIGEN data library

    Energy Technology Data Exchange (ETDEWEB)

    Hesse, U.; Hummelsheim, K.I.; Kilger, R.; Moser, F.E.; Langenbuch, S. [Gesellschaft fur Anlagen- und Reaktorsicherheit (GRS) mbH, Forschungsinstitute, Garching (Germany)

    2008-07-01

    The known ORNL ORIGEN code is widely spread over the world for inventory, activity and decay heat tasks and is used stand-alone or implemented in activation, shielding or burn-up systems. More than 1000 isotopes with more than six coupled neutron capture and radioactive decay channels are handled simultaneously by the code. The characteristics of the calculated inventories, e.g., masses, activities, neutron and photon source terms or the decay heat during short or long decay time steps are achieved by summing over all isotopes, characterized in the ORIGEN libraries. An extended nuclear GRS-ORIGENX data library is now developed for practical appliance. The library was checked for activation tasks of structure material isotopes and for actinide and fission product burn-up calculations compared with experiments and standard methods. The paper is directed to the LWR decay heat calculation features of the new library and shows the differences of dynamical and time integrated results of Endf/B-6 based and older Endf/B-5 based libraries for decay heat tasks compared to fission burst experiments, ANS curves and some other published data. A multi-group time exponential evaluation is given for the fission burst power of {sup 235}U, {sup 238}U, {sup 239}Pu and {sup 241}Pu, to be used in quick LWR reactor accident decay heat calculation tools. (authors)

  14. Radioactivity Calculations

    Science.gov (United States)

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  15. Is there a signal for Lorentz non-invariance in existing radioactive decay data?

    CERN Document Server

    Mueterthies, M J; Longman, A; Barnes, V E; Fischbach, E

    2016-01-01

    Measurements of the beta decay rates of nuclei have revealed annual periodicities with approximately the same relative amplitude even though the half-lives range over nine orders of magnitude. Here we show that this can be explained if the emitted neutrinos behave as if they propagate in a medium with a refractive index which varies as the Earth orbits the sun. This refractive index may be due to fundamental Lorentz non-invariance (LNI), or apparent LNI arising from interactions with solar or relic neutrinos, or dark matter. Additionally, this medium could have consequences for experiments attempting to measure the neutrino mass.

  16. An Excel™ model of a radioactive series

    Science.gov (United States)

    Andrews, D. G. H.

    2009-01-01

    A computer model of the decay of a radioactive series, written in Visual Basic in Excel™, is presented. The model is based on the random selection of cells in an array. The results compare well with the theoretical equations. The model is a useful tool in teaching this aspect of radioactivity.

  17. Design of cycler trajectories and analysis of solar influences on radioactive decay rates during space missions

    Science.gov (United States)

    Rogers, Blake A.

    This thesis investigates the design of interplanetary missions for the continual habitation of Mars via Earth-Mars cyclers and for the detection of variations in nuclear decay rates due to solar influences. Several cycler concepts have been proposed to provide safe and comfortable quarters for astronauts traveling between the Earth and Mars. However, no literature has appeared to show how these massive vehicles might be placed into their cycler trajectories. Trajectories are designed that use either Vinfinity leveraging or low thrust to establish cycler vehicles in their desired orbits. In the cycler trajectory cases considered, the use of Vinfinity leveraging or low thrust substantially reduces the total propellant needed to achieve the cycler orbit compared to direct orbit insertion. In the case of the classic Aldrin cycler, the propellant savings due to Vinfinity leveraging can be as large as a 24 metric ton reduction for a cycler vehicle with a dry mass of 75 metric tons, and an additional 111 metric ton reduction by instead using low thrust. The two-synodic period cyclers considered benefit less from Vinfinity leveraging, but have a smaller total propellant mass due to their lower approach velocities at Earth and Mars. It turns out that, for low-thrust establishment, the propellant required is approximately the same for each of the cycler trajectories. The Aldrin cycler has been proposed as a transportation system for human missions between Earth and Mars. However, the hyperbolic excess velocity values at the planetary encounters for these orbits are infeasibly large, especially at Mars. In a new version of the Aldrin cycler, low thrust is used in the interplanetary trajectories to reduce the encounter velocities. Reducing the encounter velocities at both planets reduces the propellant needed by the taxis (astronauts use these taxis to transfer between the planetary surfaces and the cycler vehicle) to perform hyperbolic rendezvous. While the propellant

  18. Decay data file based on the ENSDF file

    Energy Technology Data Exchange (ETDEWEB)

    Katakura, J. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    A decay data file with the JENDL (Japanese Evaluated Nuclear Data Library) format based on the ENSDF (Evaluated Nuclear Structure Data File) file was produced as a tentative one of special purpose files of JENDL. The problem using the ENSDF file as primary source data of the JENDL decay data file is presented. (author)

  19. Cold reaction valleys in the radioactive decay of superheavy {sup 286}112, {sup 292}114, and {sup 296}116 nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, K. P.; Sabina, S. [Kannur University, School of Pure and Applied Physics (India)

    2012-08-15

    Cold reaction valleys in the radioactive decay of superheavy nuclei {sup 286}112, {sup 292}114, and {sup 296}116 are studied taking Coulomb and Proximity Potential as the interacting barrier. It is found that in addition to alpha particle, {sup 8}Be, {sup 14}C, {sup 28}Mg, {sup 34}Si, {sup 50}Ca, etc. are optimal cases of cluster radioactivity since they lie in the cold valleys. Two other regions of deep minima centered on {sup 208}Pb and {sup 132}Sn are also found. Within our Coulomb and Proximity Potential Model half-life times and other characteristics such as barrier penetrability, decay constant for clusters ranging from alpha particle to {sup 68}Ni are calculated. The computed alpha half-lives match with the values calculated using Viola-Seaborg-Sobiczewski systematics. The clusters {sup 8}Be and {sup 14}C are found to be most probable for emission with T{sub 1/2} < 10{sup 30} s. The alpha-decay chains of the three superheavy nuclei are also studied. The computed alpha-decay half-lives are compared with the values predicted by Generalized Liquid Drop Model and they are found to match reasonably well.

  20. Revisit to Two-Proton Radioactivity of 19Mg and Observation of Two-Proton Decay of 30 Ar

    Institute of Scientific and Technical Information of China (English)

    徐晓栋; A. Estrad´e; F. Farinon; H. Geissel; A. Fomichev; T. A. Golubkova; A. Gorshkov; L. V. Grigorenko; Z. Janas; G. Kami´nski; O. Kiselev; I. Mukha; R. Kn¨obel; S. Krupko; M. Kuich; Yu. A. Litvinov; G. Marquinez-Dur´an; I. Martel; C. Mazzocchi; C. Nociforo; A. K. Ord´uz; M. Pf¨utzner; L. Acosta; S. Pietri; M. Pomorski; A. Prochazka; S. Rymzhanova; A. M. S´anchez-Ben´ıtez; C. Scheidenberger; P. Sharov; H. Simon; B. Sitar; R. Slepnev; E. Casarejos; M. Stanoiu; P. Strmen; I. Szarka; M. Takechi; Y. K. Tanaka; H. Weick; M. Winkler; J. S. Winfield; A. A. Ciemny; W. Dominik; J. Du´enas-D´ıaz; V. Dunin; J. M. Espino

    2016-01-01

    An experiment aimed to investigate the two-proton (2p) decay of the previously unknown nucleus 30Ar was performed at GSI. By tracking the decay products in-flight with silicon micro-strip detectors, the 2p decays of 30Ar were observed for the first time. For the calibration purpose, 2p decays of 19Mg were also remeasured by tracking the coincident 17Ne+p+p trajectories. By comparing the mea-sured angular p-17Ne correlations with those obtained from the corresponding Monte Carlo simulations, the simultaneous 2p decay of 19Mg ground state and the sequential 2p emission of several known excited states of 19Mg were confirmed. One new excited state in 19Mg and two new excited states in 18Na were observed.

  1. Fission approach to cluster radioactivity

    Indian Academy of Sciences (India)

    D N Poenaru; R A Gherghescu

    2015-09-01

    Fission theory is used to explain decay. Also, the analytical superasymmetric fission (ASAF) model is successfully employed to make a systematic search and to predict, with other models, cluster radioactivity. The macroscopic–microscopic method is illustrated for the superheavy nucleus 286Fl. Then a few results of the theoretical approach of decay (ASAF, UNIV and semFIS models), cluster decay (ASAF and UNIV) and spontaneous fission dynamics are described with Werner–Wheeler and cranking inertia. UNIV denotes universal curve and semFIS the fission-based semiempirical formula.

  2. A kinematic-based methodology for radiological protection: Runoff analysis to calculate the effective dose for internal exposure caused by ingestion of radioactive isotopes

    Science.gov (United States)

    Sasaki, Syota; Yamada, Tadashi; Yamada, Tomohito J.

    2014-05-01

    We aim to propose a kinematic-based methodology similar with runoff analysis for readily understandable radiological protection. A merit of this methodology is to produce sufficiently accurate effective doses by basic analysis. The great earthquake attacked the north-east area in Japan on March 11, 2011. The system of electrical facilities to control Fukushima Daiichi nuclear power plant was completely destroyed by the following tsunamis. From the damaged reactor containment vessels, an amount of radioactive isotopes had leaked and been diffused in the vicinity of the plant. Radiological internal exposure caused by ingestion of food containing radioactive isotopes has become an issue of great interest to the public, and has caused excessive anxiety because of a deficiency of fundamental knowledge concerning radioactivity. Concentrations of radioactivity in the human body and internal exposure have been studied extensively. Previous radiologic studies, for example, studies by International Commission on Radiological Protection(ICRP), employ a large-scale computational simulation including actual mechanism of metabolism in the human body. While computational simulation is a standard method for calculating exposure doses among radiology specialists, these methods, although exact, are too difficult for non-specialists to grasp the whole image owing to the sophistication. In this study, the human body is treated as a vessel. The number of radioactive atoms in the human body can be described by an equation of continuity, which is the only governing equation. Half-life, the period of time required for the amount of a substance decreases by half, is only parameter to calculate the number of radioactive isotopes in the human body. Half-life depends only on the kinds of nuclides, there are no arbitrary parameters. It is known that the number of radioactive isotopes decrease exponentially by radioactive decay (physical outflow). It is also known that radioactive isotopes

  3. An Excel[TM] Model of a Radioactive Series

    Science.gov (United States)

    Andrews, D. G. H.

    2009-01-01

    A computer model of the decay of a radioactive series, written in Visual Basic in Excel[TM], is presented. The model is based on the random selection of cells in an array. The results compare well with the theoretical equations. The model is a useful tool in teaching this aspect of radioactivity. (Contains 4 figures.)

  4. {beta}-decay and the electric dipole moment: searches for time-reversal violation in radioactive nuclei and atoms

    Energy Technology Data Exchange (ETDEWEB)

    Wilschut, H.W.; Hoek, D.J. van der; Jungmann, K.; Kruithof, W.; Onderwater, C.J.G.; Santra, B.; Shidling, P.; Willmann, L. [Kernfysisch Versneller Instituut, University of Groningen (Netherlands)

    2010-11-01

    At the KVI preparations are underway to study time-reversal violation. We will discuss two complementary experiments: Correlations in {beta} decay of {sup 21}Na and the search for an electric dipole moment in Radium. We discuss the complementarity of these measurements and put them in the context of current research.

  5. Research on Health Risk-Based Radioactive Acceptance Criteria of Municipal Solid Waste Landfill

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The article focuses on the topics of Health Risk-Based Radioactive Acceptance Criteria of Municipal Solid Waste Landfill (MSWL, including municipal refuse landfills or industrial solid waste landfills, MSWL). At first, health risk assessment

  6. Cluster decay half-lives of trans-lead nuclei based on a finite-range nucleon-nucleon interaction

    Science.gov (United States)

    Adel, A.; Alharbi, T.

    2017-02-01

    Nuclear cluster radioactivity is investigated using microscopic potentials in the framework of the Wentzel-Kramers-Brillouin approximation of quantum tunneling by considering the Bohr-Sommerfeld quantization condition. The microscopic cluster-daughter potential is numerically constructed in the well-established double-folding model. A realistic M3Y-Paris NN interaction with the finite-range exchange part as well as the ordinary zero-range exchange NN force is considered in the present work. The influence of nuclear deformations on the cluster decay half-lives is investigated. Based on the available experimental data, the cluster preformation factors are extracted from the calculated and the measured half lives of cluster radioactivity. Some useful predictions of cluster emission half-lives are made for emissions of known clusters from possible candidates, which may guide future experiments.

  7. -Decay and the electric dipole moment: Searches for time-reversal violation in radioactive nuclei and atoms

    Indian Academy of Sciences (India)

    H W Wilschut; U Dammalapati; D J Van Der Hoek; K Jungmann; W Kruithof; C J G Onderwater; B Santra; P D Shidling; L Willmann

    2010-07-01

    One of the greatest successes of the Standard Model of particle physics is the explanation of time-reversal violation (TRV) in heavy mesons. It also implies that TRV is immeasurably small in normal nuclear matter. However, unifying models beyond the Standard Model predict TRV to be within reach of measurement in nuclei and atoms, thus opening an important window to search for new physics. We will discuss two complementary experiments sensitive to TRV: Correlations in the -decay of 21Na and the search for an electric dipole moment (EDM) in radium.

  8. Decay ring design

    CERN Document Server

    Chancé, A; Bouquerel, E; Hancock, S; Jensen, E

    The study of the neutrino oscillation between its different flavours needs pureand very intense fluxes of high energy, well collimated neutrinos with a welldetermined energy spectrum. A dedicated machine seems to be necessarynowadays to reach the required flux. A new concept based on the β-decayof radioactive ions which were accelerated in an accelerator chain was thenproposed. After ion production, stripping, bunching and acceleration, the unstableions are then stored in a racetrack-shaped superconducting decay ring.Finally, the ions are accumulated in the decay ring until being lost. The incomingbeam is merged to the stored beam by using a specific RF system, whichwill be presented here.We propose here to study some aspects of the decay ring, such as its opticalproperties, its RF system or the management of the losses which occur in thering (mainly by decay or by collimation).

  9. Integrated data base report--1996: US spent nuclear fuel and radioactive waste inventories, projections, and characteristics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    The Integrated Data Base Program has compiled historic data on inventories and characteristics of both commercial and U.S. Department of Energy (DOE) spent nuclear fuel (SNF) and commercial and U.S. government-owned radioactive wastes. Inventories of most of these materials are reported as of the end of fiscal year (FY) 1996, which is September 30, 1996. Commercial SNF and commercial uranium mill tailings inventories are reported on an end-of-calendar year (CY) basis. All SNF and radioactive waste data reported are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest DOE/Energy Information Administration (EIA) projections of U.S. commercial nuclear power growth and the expected DOE-related and private industrial and institutional activities. The radioactive materials considered, on a chapter-by-chapter basis, are SNF, high-level waste, transuranic waste, low-level waste, uranium mill tailings, DOE Environmental Restoration Program contaminated environmental media, naturally occurring and accelerator-produced radioactive material, and mixed (hazardous and radioactive) low-level waste. For most of these categories, current and projected inventories are given through FY 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions.

  10. Accelerator development for a radioactive beam facility based on ATLAS.

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K. W.

    1998-01-08

    The existing superconducting linac ATLAS is in many respects an ideal secondary beam accelerator for an ISOL (Isotope separator on-line) type radioactive beam facility. Such a facility would require the addition of two major accelerator elements: a low charge state injector for the existing heavy ion linac, and a primary beam accelerator providing 220 MV of acceleration for protons and light ions. Development work for both of these elements, including the option of superconducting cavities for the primary beam accelerator is discussed.

  11. Dynamical analysis of an accelerator-based fluid-fueled subcritical radioactive waste burning system

    Science.gov (United States)

    Woosley, Michael Louis, Jr.

    The recent revival of interest in accelerator-driven subcritical fluid-fueled systems is documented. Several important applications of these systems are mentioned. In particular, new applications have focused on the destruction of high-level radioactive waste. Systems can be designed to quickly destroy the actinides and long-lived fission products from light water reactor fuel, weapons plutonium, and other high-level defense wastes. The proposed development of these systems is used to motivate the need for the development of dynamic analysis methods for their nuclear kinetics. A physical description of the Los Alamos Accelerator-Based Conversion (ABC) concept is provided. This system is used as the basis for the kinetics study in this research. The current approach to the dynamic simulation of an accelerator-driven subcritical fluid-fueled system includes three elements: A discrete ordinates model is used to calculate the flux distribution for the source-driven system; A nodal convection model is used to calculate time-dependent isotope and temperature distributions which impact reactivity; A nodal importance weighting model is used to calculate the reactivity impact of temperature and isotope distributions and to feed this information back to the time-dependent nodal convection model. Specific transients which have been analyzed with the current modeling system are discussed. These transients include loss-of-flow and loss-of-cooling accidents, xenon and samarium transients, and cold-plug and overfueling events. The results of various transients have uncovered unpredictable behavior, unresolved design issues, and the need for active control. Modest initiating events can cause significant swings in system temperature and power. The circulation of the fluid fuel can lead to oscillations on the relatively short scale of the loop circulation time. The system responds quickly to reactivity changes because the large neutron source overwhelms the damping effect of delayed

  12. The full structure of the KLL Auger spectrum of La observed in the radioactive decay of {sup 139}Ce in a solid matrix

    Energy Technology Data Exchange (ETDEWEB)

    Inoyatov, A.Kh., E-mail: inoyatov@nusun.jinr.ru [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Institute of Applied Physics, National University, Tashkent (Uzbekistan); Perevoshchikov, L.L. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Kovalík, A. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Nuclear Physics Institute of the ASCR, Řež near Prague (Czech Republic); Filosofov, D.V. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Zhdanov, V.S. [Institute of Nuclear Physics, Almaty (Kazakhstan); Lubashevskiy, A.V. [Laboratory of Nuclear Problems, JINR, Dubna, Moscow Region (Russian Federation); Hons, Z. [Nuclear Physics Institute of the ASCR, Řež near Prague (Czech Republic)

    2013-04-15

    Highlights: •The KLL Auger spectrum of Ce measured for the first time in detail. •Energies and relative intensities of the all nine basic spectrum components determined. •An influence of the “atomic structure effect” on the absolute KLL energies indicated. •A perceptible influence of the relativistic effects on the KLL spectrum found. -- Abstract: For the first time, the KLL Auger spectrum of La (Z = 57) following the electron capture decay of radioactive {sup 139,141}Ce in a solid source was measured. The all nine basic spectrum components were resolved and their energies and relative intensities were determined and compared with theoretical expectations. The absolute energy of 27 383.8 ± 2.2 eV derived for the dominant KL{sub 2}L{sub 3}({sup 1}D{sub 2}) transition was found to be higher by 7.7 ± 2.2 eV (i.e. more than 3σ) than a value predicted by the widely used relativistic semi-empirical calculations by Larkins. The possible reasons for this discrepancy are discussed. Despite of less accuracy of some measured data, the predicted strong influence of the relativistic effects on the KL{sub 1}L{sub 2}({sup 3}P{sub 0}) transition intensity was nevertheless proved.

  13. Integrated data base report - 1994: US spent nuclear fuel and radioactive waste inventories, projections, and characteristics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    The Integrated Data Base Program has compiled historic data on inventories and characteristics of both commercial and U.S. Department of Energy (DOE) spent nuclear fuel and commercial and U.S. government-owned radioactive wastes. Except for transuranic wastes, inventories of these materials are reported as of December 31, 1994. Transuranic waste inventories are reported as of December 31, 1993. All spent nuclear fuel and radioactive waste data reported are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest DOE/Energy Information Administration (EIA) projections of U.S. commercial nuclear power growth and the expected DOE-related and private industrial and institutional activities. The radioactive materials considered, on a chapter-by-chapter basis, are spent nuclear fuel, high-level waste, transuranic waste, low-level waste, commercial uranium mill tailings, DOE Environmental Restoration Program contaminated environmental media, commercial reactor and fuel-cycle facility decommissioning wastes, and mixed (hazardous and radioactive) low-level waste. For most of these categories, current and projected inventories are given through the calendar-year 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions.

  14. Efficient Removal of Cationic and Anionic Radioactive Pollutants from Water Using Hydrotalcite-Based Getters.

    Science.gov (United States)

    Bo, Arixin; Sarina, Sarina; Liu, Hongwei; Zheng, Zhanfeng; Xiao, Qi; Gu, Yuantong; Ayoko, Godwin A; Zhu, Huaiyong

    2016-06-29

    Hydrotalcite (HT)-based materials are usually applied to capture anionic pollutants in aqueous solutions. Generally considered anion exchangers, their ability to capture radioactive cations is rarely exploited. In the present work, we explored the ability of pristine and calcined HT getters to effectively capture radioactive cations (Sr(2+) and Ba(2+)) which can be securely stabilized at the getter surface. It is found that calcined HT outperforms its pristine counterpart in cation removal ability. Meanwhile, a novel anion removal mechanism targeting radioactive I(-) is demonstrated. This approach involves HT surface modification with silver species, namely, Ag2CO3 nanoparticles, which can attach firmly on HT surface by forming coherent interface. This HT-based anion getter can be further used to capture I(-) in aqueous solution. The observed I(-) uptake mechanism is distinctly different from the widely reported ion exchange mechanism of HT and much more efficient. As a result of the high local concentrations of precipitants on the getters, radioactive ions in water can be readily immobilized onto the getter surface by forming precipitates. The secured ionic pollutants can be subsequently removed from water by filtration or sedimentation for safe disposal. Overall, these stable, inexpensive getters are the materials of choice for removal of trace ionic pollutants from bulk radioactive liquids, especially during episodic environmental crisis.

  15. Biotesting of radioactively contaminated forest soils using barley-based bioassay

    Science.gov (United States)

    Mel’nikova, T. V.; Polyakova, L. P.; Oudalova, A. A.

    2017-01-01

    Findings from radioactivity and phytotoxicity study are presented for soils from nine study-sites of the Klintsovsky Forestry located in the Bryansk region that were radioactively contaminated after the Chernobyl accident. According to the bioassay based on barley as test-species, stimulating effect of the soils analyzed is revealed for biological indexes of the length of barley roots and sprouts. From data on 137Cs specific activities in soils and plant biomass, the migration potential of radionuclide in the "soil-plant" system is assessed as a transfer factor. With correlation analysis, an impact of 137Cs in soil on the biological characteristics of barley is estimated.

  16. Risk perception, risk evaluation and human values: cognitive bases of acceptability of a radioactive waste repository

    Energy Technology Data Exchange (ETDEWEB)

    Earle, T.C.; Lindell, M.K.; Rankin, W.L.

    1981-07-01

    Public acceptance of radioactive waste management alternatives depends in part on public perception of the associated risks. Three aspects of those perceived risks were explored in this study: (1) synthetic measures of risk perception based on judgments of probability and consequences; (2) acceptability of hypothetical radioactive waste policies, and (3) effects of human values on risk perception. Both the work on synthetic measures of risk perception and on the acceptability of hypothetical policies included investigations of three categories of risk: (1) Short-term public risk (affecting persons living when the wastes are created), (2) Long-term public risk (affecting persons living after the time the wastes were created), and (3) Occupational risk (affecting persons working with the radioactive wastes). The human values work related to public risk perception in general, across categories of persons affected. Respondents were selected according to a purposive sampling strategy.

  17. Effect of self-glazing on reducing the radioactivity levels of red mud based ceramic materials.

    Science.gov (United States)

    Qin, Shuo; Wu, Bolin

    2011-12-30

    Self-glazing red mud based ceramic materials (RMCM) were produced by normal pressure sintering process using the main raw materials of red mud. The properties of the RMCM samples were investigated by the measurements of mechanical properties, radiation measurement, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the self-glazing RMCM have good mechanical properties (water absorption and apparent porosity approached zero; bulk density, 2.94 g/cm(3); compressive strength, 78.12 MPa). The radiation level has clear change regularity that the radioactivity levels of red mud (6360 Bq) is obvious declined, and can be reduced to that of the natural radioactive background of Guilin Karst landform, China (3600 Bq). It will not only consume large quantities of red mud, but also decrease the production cost of self-glazing RMCM. And the statement of this paper will offer effective ways to reduce the radioactivity level of red mud.

  18. 陶瓷材料放射性核素测量样品衰变时间研究及最短平衡周期的确定%The Radioactive Decay Time of Ceramic Materials Radionuclide Test Specimen and Determination of the Shortest Decay Balance Cycle

    Institute of Scientific and Technical Information of China (English)

    李文杰; 鲁学军; 杨宝星

    2016-01-01

    This paper sketched the theory of radioactive samples’ decay balance cycle The speciifc activity of three groups of specimens with the radioactive decay balance time between 0 to 27 days was tested by sodium iodideγ-ray detector, then the differences between test results of the same specimen after different decay balance time were analyzed using t-test method. Researches show that if the signiifcant difference between the test results is 5%, the shortest radioactive decay time should not be less than 12 days.%简述了陶瓷材料放射性衰变平衡的基本理论,利用碘化钠γ谱仪对0-27 d内不同衰变时长的3组样品进行比活度测定,采用t检验法分析了同一组样品在不同衰变时间条件下放射性测量结果之间的差异程度。研究表明,若确保检测结果数据的显著性差异水平为5%,则样品最短衰变时间应不小于12 d。

  19. Use of sampling based correction for non-radioactivity X-ray energy calibration

    Institute of Scientific and Technical Information of China (English)

    CHENG Cheng; WEI Yong-Bo; JIANG Da-Zhen

    2005-01-01

    As the requirement of non-radioactivity measurement has increased in recent years, various energy calibration methods applied in portable X-ray fluorescence (XRF) spectrometers have been developed. In this paper, a sampling based correction energy calibration has been discussed. In this method both history information and current state of the instrument are considered and relative high precision and reliability can be obtained.

  20. Kinetic characteristics of the luminescence decay for industrial yttrium-gadolinium-aluminium garnet based phosphors

    OpenAIRE

    Lisitsyn, Viktor Mikhailovich; Stepanov, Sergey Aleksandrovich; Valiev, Damir Talgatovich; Vishnyakova, E. A.; Abdullin, H. A.; Marhabaeva, A. A.; Tulegenova, A. T.

    2016-01-01

    The spectral and decay kinetic characteristics of pulse cathodoluminescence and photoluminescence of phosphors based on yttrium-gadolinium-aluminum garnet were investigated using pulsed optical time resolved spectroscopy.

  1. Introduction to Astronomy with Radioactivity

    CERN Document Server

    Diehl, Roland

    2010-01-01

    In the late nineteenth century, Antoine Henri Becquerel discovered radioactivity and thus the physics of weak interactions, well before atomic and quantum physics was known. The different types of radioactive decay, alpha, beta, and gamma decay, all are different types of interactions causing the same, spontaneous, and time-independent decay of an unstable nucleus into another and more stable nucleus. Nuclear reactions in cosmic sites re-arrange the basic constituents of atomic nuclei (neutrons and protons) among the different configurations which are allowed by Nature, thus producing radioactive isotopes as a by-product. Throughout cosmic history, such reactions occur in different sites, and lead to rearrangements of the relative abundances of cosmic nuclei, a process called cosmic chemical evolution, which can be studied through the observations of radioactivity. The special role of radioactivity in such studies is contributed by the intrinsic decay of such material after it has been produced in cosmic site...

  2. Fixation and mobilisation of uranium and its radioactive decay products in C-richwater sediments; Festlegung und Mobilisierung von Uran und seinen radioaktiven Zerfallsprodukten in kohlenstoffreichen Gewaessersedimenten

    Energy Technology Data Exchange (ETDEWEB)

    Nassour, Mohammad

    2014-05-27

    organic carbon as main metabolic energy source for low order lotic ecosystems on the fixation of uranium was investigated by analyzing, the effects of leaves (coarse particulate organic matter: CPOM) and their degradation products (mainly fine particulate organic matter: FPOM and biofilms etc.). It was found that the highly mobile fraction of uranium in the water pathway, preferably present under the given conditions in the form different uranyl-carbonato-complexes, is efficiently fixed on fresh organic plant material (plant litter, leaves) in the first steps of organic matter decomposition within a few days. But it also can be immobilized relatively stable. It was also found that CPOM is a temporary sink for uranium, which may be sedimented depending on the turbulence flow and discharge. This may contribute to the directional removal of uranium from the water into the sediment. Finally this work analyzed the conditions in the pelagic and benthic zone of the Neuensalz pre dam of the Poehl reservoir, which is located downstream of the mining site. It presents a periodically stagnant water body with seasonally continuous sedimentation, a possible stable sink of uranium and products of radioactive decay in early diagenesis. Water samples of the pelagic zone and undisturbed sediment cores were taken and analyzed during winter stagnation. The results are discussed in front of seasonal changes in water chemistry and load data. {sup 238}U and {sup 226}Ra showed a culmination of activity concentrations in the sediment horizons from 25 to 35 cm depth, in particular at a centrally located sampling point (K3). At this point highest activity concentrations of {sup 238}U were found with a median value of 770 Bq*kg{sup -1} at a depth of 30 cm. At the same location {sup 226}Ra shows activity concentrations of 250 Bq*kg{sup -1}(median). Based on the {sup 137}Cs dating method a sedimentation rate of 1.5 cm*yr{sup -1} was calculated for the pre-dam Neuensalz sediment. On average

  3. Calibration of a radioactive ink-based stack phantom and its applications in nuclear medicine.

    Science.gov (United States)

    El-Ali, H; Ljungberg, M; Strand, S-E; Palmer, J; Malmgren, L; Nilsson, J

    2003-04-01

    This paper describes a stack phantom useful for imaging complex activity distributions. It is based on images printed with radioactive ink using a commercial ink-jet printer. The application for the phantom is in the evaluation of planar and SPECT scintillation camera images and for validation of Monte Carlo simulated images. The accuracy in generating the activity distributions on paper sheets is especially important. Here we describe the calibration procedure for the ink-jet printer. The goal of the printer calibration is to find the relationship between the digital image count (voxel grey level) and its corresponding activity on the paper sheets (radioactivity). The relationship between the voxel grey level and the radioactivity on the paper sheets (measured by scanning technique and well counter) was found to be logarithmic, and a 3rd degree polynomial was found to fit the relationship. The distribution of radioactivity in the ink cartridge was investigated by pinhole SPECT. The distribution of (99m)Tc solution was found to be homogeneous in the ink solution. Experimental studies were done directly on Monte Carlo simulated heart images from the NCAT phantom. The result showed that the simulated images are similar to the images measured using the ink-jet technique. This stack phantom could be a promising solution with an advantage that the exact geometry generated in Monte Carlo could be imitated in the phantom. The phantom is a very flexible device and clearly much more versatile than conventional phantoms which have a fixed geometry and spatial limitation.

  4. Cement-based grouts in geological disposal of radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Onofrei, M. [AECL Research, Pinnawa, Manitoba (Canada)

    1996-04-01

    The behavior and performance of a specially developed high-performance cement-based grout has been studied through a combined laboratory and in situ research program conducted under the auspices of the Canadian Nuclear Fuel Waste Management Program (CNFWMP). A new class of cement-based grouts - high-performance grouts-with the ability to penetrate and seal fine fractures was developed and investigated. These high-performance grouts, which were injected into fractures in the granitic rock at the Underground Research Laboratory (URL) in Canada, are shown to successfully reduce the hydraulic conductivity of the rock mass from <10{sup -7} m s{sup -1} to 10{sup -9} m s{sup -1} and to penetrate fissures in the rock with apertures as small as 10 {mu}m. Furthermore, the laboratory studies have shown that this high - performance grout has very low hydraulic conductivity and is highly leach resistant under repository conditions. Microcracks generated in this materials from shrinkage, overstressing or thermal loads are likely to self-seal. The results of these studies suggest that the high-performance grouts can be considered as viable materials in disposal-vault sealing applications. Further work is needed to fully justify extrapolation of the results of the laboratory studies to time scales relevant to performance assessment.

  5. Review on Preservative Treatment and Decay Resistance of Wood-based Composites

    Institute of Scientific and Technical Information of China (English)

    LIU Zhi; CAO Jinzhen

    2006-01-01

    To extend the service life and explore the use of wood-based composites, it is quite necessary to improve the decay resistance of wood-based composites through preservative treatments. Researchers have studied the methods of preservative treatment and the decay resistance of treated wood-based composites. In this paper, the categories of wood-based composites are briefly summarized and the previous and present investigations on the preservative treatment and decay resistance of different categories of wood-based composites are introduced. Some problems are also put forward and suggestions are given for future studies.

  6. Effect of self-glazing on reducing the radioactivity levels of red mud based ceramic materials

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Shuo [College of Material Science and Engineering, Guilin University of Technology, Guilin, Guangxi 541004 (China); Wu, Bolin, E-mail: wubolin3211@gmail.com [College of Material Science and Engineering, Guilin University of Technology, Guilin, Guangxi 541004 (China)

    2011-12-30

    Graphical abstract: Self-glazing red mud based ceramic materials (RMCM) were produced by normal pressure sintering process using the main raw materials of red mud. The properties of the RMCM samples were investigated by the measurements of mechanical properties, radiation measurement, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the self-glazing RMCM have good mechanical properties (water absorption and apparent porosity approached zero; bulk density, 2.94 g/cm{sup 3}; compressive strength, 78.12 MPa). The radiation level has clear change regularity that the radioactivity levels of red mud (6360 Bq) are obvious declined, and can be reduced to that of the natural radioactive background of Guilin Karst landform, China (3600 Bq). It will not only consume large quantities of red mud, but also decrease the production cost of self-glazing RMCM. And the statement of this paper will offer effective ways to reduce the radioactivity level of red mud. Highlights: Black-Right-Pointing-Pointer The self-glazing phenomenon in red mud system was first discovered in our research. Black-Right-Pointing-Pointer Radiation levels of red mud can be reduced efficiently by self-glazing layer. Black-Right-Pointing-Pointer Red mud based ceramic materials will not cause harm to environment and humans. Black-Right-Pointing-Pointer This research possesses important economic significances to aluminum companies. - Abstract: Self-glazing red mud based ceramic materials (RMCM) were produced by normal pressure sintering process using the main raw materials of red mud. The properties of the RMCM samples were investigated by the measurements of mechanical properties, radiation measurement, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the self-glazing RMCM have good mechanical properties (water absorption and apparent porosity approached zero; bulk density, 2.94 g/cm{sup 3}; compressive strength, 78.12 MPa). The radiation

  7. Radioactivity doubles up

    Science.gov (United States)

    Blank, Bertram

    2008-05-01

    More than a century after Henri Becquerel discovered radioactivity, there is still much that physicists do not understand about this spontaneous natural phenomenon. Through Becquerel's use of simple photographic plates to the sophisticated nuclear experiments carried out in today's laboratories, researchers have unearthed a total of nine different ways in which an atomic nucleus can decay. The most well known of these decay modes - alpha (α), beta (β) and gamma (γ) radioactivity - are widely used in applications ranging from medicine to archaeology; the others are much rarer.

  8. Low-level radioactive waste source terms for the 1992 integrated data base

    Energy Technology Data Exchange (ETDEWEB)

    Loghry, S L; Kibbey, A H; Godbee, H W; Icenhour, A S; DePaoli, S M

    1995-01-01

    This technical manual presents updated generic source terms (i.e., unitized amounts and radionuclide compositions) which have been developed for use in the Integrated Data Base (IDB) Program of the U.S. Department of Energy (DOE). These source terms were used in the IDB annual report, Integrated Data Base for 1992: Spent Fuel and Radioactive Waste Inventories, Projections, and Characteristics, DOE/RW-0006, Rev. 8, October 1992. They are useful as a basis for projecting future amounts (volume and radioactivity) of low-level radioactive waste (LLW) shipped for disposal at commercial burial grounds or sent for storage at DOE solid-waste sites. Commercial fuel cycle LLW categories include boiling-water reactor, pressurized-water reactor, fuel fabrication, and uranium hexafluoride (UF{sub 6}) conversion. Commercial nonfuel cycle LLW includes institutional/industrial (I/I) waste. The LLW from DOE operations is category as uranium/thorium fission product, induced activity, tritium, alpha, and {open_quotes}other{close_quotes}. Fuel cycle commercial LLW source terms are normalized on the basis of net electrical output [MW(e)-year], except for UF{sub 6} conversion, which is normalized on the basis of heavy metal requirement [metric tons of initial heavy metal ]. The nonfuel cycle commercial LLW source term is normalized on the basis of volume (cubic meters) and radioactivity (curies) for each subclass within the I/I category. The DOE LLW is normalized in a manner similar to that for commercial I/I waste. The revised source terms are based on the best available historical data through 1992.

  9. Contribution of the radioactive decay to the study of the structure of N=Z nuclei of mass A>70; Apport de la decroissance radioactive a l'etude de la structure des noyaux N=Z de masse A>70

    Energy Technology Data Exchange (ETDEWEB)

    Longour, Christophe [Institut de Recherches Subatomiques, B.P.28, 23, Rue du Loess, F-67037 Strasbourg Cedex 2 (France)

    1999-04-21

    Radioactive decay study gives an access to the interaction which rules the {beta} decay process as well as the structure of the nuclear states involved. This work describes the observation of the decay of N = Z nuclei with mass A > 70. For the odd-odd N = Z nuclei {sup 78}Y, {sup 82}Nb and {sup 86}Tc, the decay has been established as superallowed Fermi type transitions. The results pave the way for more precise measurements and extend the mass range nowadays used to understand the behaviour of the weak interaction in the nuclear matter. The observation of the decay of the even-even N = Z {sup 72}Kr leads us to build the Gamow-Teller strength distribution from which some clues about the ground state deformation of this isotope can be obtained. More complete experimental observation and some developments of the calculations used to interpret the distribution of the Gamow-Teller strength are needed. Finally, this work describes the developments and tests of a prototype detector the aim of which to determine the contribution of {beta} particles to energy distribution observed in germanium detector. The tests we have performed show that this prototype can identify and reject 80% of the {beta} particles emitted by a source with a 2,3 MeV end-point. The very satisfactory performances of this prototype need now to be confirmed under experimental conditions.

  10. Computer code for double beta decay QRPA based calculations

    Energy Technology Data Exchange (ETDEWEB)

    Barbero, C. A.; Mariano, A. [Departamento de Física, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina and Instituto de Física La Plata, CONICET, La Plata (Argentina); Krmpotić, F. [Instituto de Física La Plata, CONICET, La Plata, Argentina and Instituto de Física Teórica, Universidade Estadual Paulista, São Paulo (Brazil); Samana, A. R.; Ferreira, V. dos Santos [Departamento de Ciências Exatas e Tecnológicas, Universidade Estadual de Santa Cruz, BA (Brazil); Bertulani, C. A. [Department of Physics, Texas A and M University-Commerce, Commerce, TX (United States)

    2014-11-11

    The computer code developed by our group some years ago for the evaluation of nuclear matrix elements, within the QRPA and PQRPA nuclear structure models, involved in neutrino-nucleus reactions, muon capture and β{sup ±} processes, is extended to include also the nuclear double beta decay.

  11. Predicted halflives for cluster radioactivities

    Science.gov (United States)

    Poenaru, D. N.; Greiner, W.; Ivascu, M.

    1989-10-01

    The main results of the analytical superasymmetric fission model, describing in a unified manner cluster radioactivities, alpha-decay and cold fission processes, are briefly reviewed. Predicted halflives for 14C, 24, 25, 26Ne, 28, 30Mg and 32Si radioactivities in the range 10 11-10 26 s and the corresponding branching ratios relative to α-decay 10 -16 - 10 -9 have been experimentally confirmed within 1.5 orders of magnitude.

  12. Radioactive Threat Detection with Scattering Physics: A Model-Based Application

    Energy Technology Data Exchange (ETDEWEB)

    Candy, J V; Chambers, D H; Breitfeller, E F; Guidry, B L; Verbeke, J M; Axelrod, M A; Sale, K E; Meyer, A M

    2010-01-21

    The detection of radioactive contraband is a critical problem in maintaining national security for any country. Emissions from threat materials challenge both detection and measurement technologies especially when concealed by various types of shielding complicating the transport physics significantly. The development of a model-based sequential Bayesian processor that captures both the underlying transport physics including scattering offers a physics-based approach to attack this challenging problem. It is shown that this processor can be used to develop an effective detection technique.

  13. A_4-based neutrino masses with Majoron decaying dark matter

    CERN Document Server

    Esteves, J N; Joshipura, A S; Romao, J C; Tortola, M A; Valle, J W F

    2010-01-01

    We propose an A_4 flavor-symmetric SU(3)xSU(2)xU(1) seesaw model where lepton number is broken spontaneously. A consistent two-zero texture pattern of neutrino masses and mixing emerges from the interplay of type-I and type-II seesaw contributions, with important phenomenological predictions. We show that, if the Majoron becomes massive, such seesaw scenario provides a viable candidate for decaying dark matter, consistent with cosmic microwave background lifetime constraints that follow from current WMAP observations. We also calculate the sub-leading one-loop-induced decay into photons which leads to a mono-energetic emission line that may be observed in future X-ray missions such as Xenia.

  14. Disposal of radioactive waste. Some ethical aspects

    Energy Technology Data Exchange (ETDEWEB)

    Streffer, Christian

    2014-07-01

    The threat posed to humans and nature by radioactive material is a result of the ionizing radiation released during the radioactive decay. The present use of radioactivity in medicine research and technologies produces steadily radioactive waste. It is therefore necessary to safely store this waste, particularly high level waste from nuclear facilities. The decisive factors determining the necessary duration of isolation or confinement are the physical half-life times ranging with some radionuclides up to many million years. It has therefore been accepted worldwide that the radioactive material needs to be confined isolated from the biosphere, the habitat of humans and all other organisms, for very long time periods. Although it is generally accepted that repositories for the waste are necessary, strong public emotions have been built up against the strategies to erect such installations. Apparently transparent information and public participation has been insufficient or even lacking. These problems have led to endeavours to achieve public acceptance and to consider ethical acceptability. Some aspects of such discussions and possibilities will be taken up in this contribution. This article is based on the work of an interdisciplinary group. The results have been published in 'Radioactive Waste - Technical and Normative Aspects of its Disposal' by C. Streffer, C.F. Gethmann, G. Kamp et al. in 'Ethics of Sciences and Technology Assessment', Volume 38, Springer-Verlag Berlin Heidelberg 2011.

  15. Integrated data base report--1995: US spent nuclear fuel and radioactive waste inventories, projections, and characteristics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The information in this report summarizes the U.S. Department of Energy (DOE) data base for inventories, projections, and characteristics of domestic spent nuclear fuel and radioactive waste. This report is updated annually to keep abreast of continual waste inventory and projection changes in both the government and commercial sectors. Baseline information is provided for DOE program planning purposes and to support DOE program decisions. Although the primary purpose of this document is to provide background information for program planning within the DOE community, it has also been found useful by state and local governments, the academic community, and some private citizens.

  16. A cheap and compact mass spectrometer for radioactive ions based on a Wien filter

    Science.gov (United States)

    Pierret, C.; Maunoury, L.; Pacquet, J. Y.; Saint-Laurent, M.-G.; Tuske, O.

    2008-10-01

    This paper presents simulations of a mass spectrometer composed of one or two Wien filters. The ion source used is MONO1000 ECRIS. This ion source can produce singly charged ions with high efficiency, especially for gaseous materials. After extraction, the ions are mass selected and can be injected either into a beam line towards an experiment area or in an N+ charge booster. Due to its compactness and simplicity the proposed spectrometer is well adapted for preparing and analyzing radioactive beams. The simulations are based on the SIMION 3D [www.simion.com/] software.

  17. A cheap and compact mass spectrometer for radioactive ions based on a Wien filter

    Energy Technology Data Exchange (ETDEWEB)

    Pierret, C. [CIRIL, CEA/DSM CNRS/IN2P3, Avenue Henri Becquerel, B.P. 5133, F-14070 Caen cedex 05 (France)], E-mail: Pierret@ganil.fr; Maunoury, L. [CIRIL, CEA/DSM CNRS/IN2P3, Avenue Henri Becquerel, B.P. 5133, F-14070 Caen cedex 05 (France); Pacquet, J.Y.; Saint-Laurent, M.-G. [GANIL, CEA/DSM CNRS/IN2P3, Boulevard Henri Becquerel, B.P. 55027, F-14076 Caen cedex 05 (France); Tuske, O. [CEA/Saclay, DSM/DAPNIA, 91191 Gif/Yvette (France)

    2008-10-15

    This paper presents simulations of a mass spectrometer composed of one or two Wien filters. The ion source used is MONO1000 ECRIS. This ion source can produce singly charged ions with high efficiency, especially for gaseous materials. After extraction, the ions are mass selected and can be injected either into a beam line towards an experiment area or in an N{sup +} charge booster. Due to its compactness and simplicity the proposed spectrometer is well adapted for preparing and analyzing radioactive beams. The simulations are based on the SIMION 3D [ (http://www.simion.com/)] software.

  18. NaI(Tl) Detector Efficiency Computation Using Radioactive Parallelepiped Sources Based on Efficiency Transfer Principle

    OpenAIRE

    MOHAMED S. BADAWI; Mona M. Gouda; Ahmed M. El-Khatib; Thabet, Abouzeid A.; Salim, Ahmed A.; Mahmoud I. Abbas

    2015-01-01

    The efficiency transfer (ET) principle is considered as a simple numerical simulation method, which can be used to calculate the full-energy peak efficiency (FEPE) of 3″×3″ NaI(Tl) scintillation detector over a wide energy range. In this work, the calculations of FEPE are based on computing the effective solid angle ratio between a radioactive point and parallelepiped sources located at various distances from the detector surface. Besides, the attenuation of the photon by the source-to-detect...

  19. On-site radioactive soil contamination at the Andreeva Bay shore technical base, Northwest Russia

    NARCIS (Netherlands)

    Reistad, O.; Dowdall, M.; Selnaes, O. G.; Standring, W. J. F.; Hustveit, S.; Steenhuisen, F.; Sorlie, A.

    2008-01-01

    The radioactive waste (RAW) storage site at Andreeva Bay in the Russian Northwest has experienced radioactive contamination both as a result of activities carried out at the site and due to incidents that have occurred there in the past such as accidental releases of radioactive materials. The site

  20. Physics-based, Bayesian sequential detection method and system for radioactive contraband

    Science.gov (United States)

    Candy, James V; Axelrod, Michael C; Breitfeller, Eric F; Chambers, David H; Guidry, Brian L; Manatt, Douglas R; Meyer, Alan W; Sale, Kenneth E

    2014-03-18

    A distributed sequential method and system for detecting and identifying radioactive contraband from highly uncertain (noisy) low-count, radionuclide measurements, i.e. an event mode sequence (EMS), using a statistical approach based on Bayesian inference and physics-model-based signal processing based on the representation of a radionuclide as a monoenergetic decomposition of monoenergetic sources. For a given photon event of the EMS, the appropriate monoenergy processing channel is determined using a confidence interval condition-based discriminator for the energy amplitude and interarrival time and parameter estimates are used to update a measured probability density function estimate for a target radionuclide. A sequential likelihood ratio test is then used to determine one of two threshold conditions signifying that the EMS is either identified as the target radionuclide or not, and if not, then repeating the process for the next sequential photon event of the EMS until one of the two threshold conditions is satisfied.

  1. Fracture mechanics based design for radioactive material transport packagings -- Historical review

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.A.; Salzbrenner, D.; Sorenson, K.; McConnell, P.

    1998-04-01

    The use of a fracture mechanics based design for the radioactive material transport (RAM) packagings has been the subject of extensive research for more than a decade. Sandia National Laboratories (SNL) has played an important role in the research and development of the application of this technology. Ductile iron has been internationally accepted as an exemplary material for the demonstration of a fracture mechanics based method of RAM packaging design and therefore is the subject of a large portion of the research discussed in this report. SNL`s extensive research and development program, funded primarily by the U. S. Department of Energy`s Office of Transportation, Energy Management and Analytical Services (EM-76) and in an auxiliary capacity, the office of Civilian Radioactive Waste Management, is summarized in this document along with a summary of the research conducted at other institutions throughout the world. In addition to the research and development work, code and standards development and regulatory positions are also discussed.

  2. Management of radioactive waste: A review

    Directory of Open Access Journals (Sweden)

    Luis Paulo Sant'ana

    2016-06-01

    Full Text Available The issue of disposal of radioactive waste around the world is not solved by now and the principal reason is the lack of an efficient technologic system. The fact that radioactive waste decays of radioactivity with time are the main reasons for setting nuclear or radioactive waste apart from the other common hazardous wastes management. Radioactive waste can be classified according to the state of matter and level of radioactivity and this classification can be differently interpreted from country to country. Furthermore, microbiological procedures, plasma vitrification process, chemical precipitation, ion exchange, evaporation and reverse osmosis are strategies used for the treatment of radioactive wastes. The major challenge is to manage these radioactive substances after being used and discharged. This report brings data from the literature published worldwide from 2009 to 2014 on radioactive waste management studies and it covers production, classification and management of radioactive solid, liquid and gas waste.

  3. Radioactive waste caracterisation by neutron activation

    OpenAIRE

    Nicol, Tangi

    2016-01-01

    Nuclear activities produce radioactive wastes classified following their radioactive level and decay time. An accurate characterization is necessary for efficient classification and management. Medium and high level wastes containing long lived radioactive isotopes will be stored in deep geological storage for hundreds of thousands years. At the end of this period, it is essential to ensure that the wastes do not represent any risk for humans and environment, not only from radioactive point o...

  4. Low-energy nuclear reactions with double-solenoid- based radioactive nuclear beam

    Indian Academy of Sciences (India)

    Valdir Guimarães

    2010-07-01

    The University of Notre Dame, USA (Becchetti et al, Nucl. Instrum. Methods Res. A505, 377 (2003)) and later the University of São Paulo, Brazil (Lichtenthaler et al, Eur. Phys. J. A25, S-01, 733 (2005)) adopted a system based on superconducting solenoids to produce low-energy radioactive nuclear beams. In these systems the solenoids act as thick lenses to collect, select, and focus the secondary beam into a scattering chamber. Many experiments with radioactive light particle beams (RNB) such as 6He, 7Be, 8Li, 8B have been performed at these two facilities. These low-energy RNB have been used to investigate low-energy reactions such as elastic scattering, transfer and breakup, providing useful information on the structure of light nuclei near the drip line and on astrophysics. Total reaction cross-sections, derived from elastic scattering analysis, have also been investigated for light system as a function of energy and the role of breakup of weakly bound or exotic nuclei is discussed.

  5. Integrated Data Base report--1993: U.S. spent nuclear fuel and radioactive waste inventories, projections, and characteristics. Revision 10

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-01

    The Integrated Data Base Program has compiled historic data on inventories and characteristics of both commercial and DOE spent nuclear fuel; also, commercial and US government-owned radioactive wastes through December 31, 1993. These data are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest US Department of Energy/Energy Information Administration projections of US commercial nuclear power growth and the expected DOE-related and private industrial and institutional activities. The radioactive materials considered, on a chapter-by-chapter basis, are spent nuclear fuel, high-level waste, transuranic waste, low-level waste, commercial uranium mill tailings, DOE Environmental Restoration Program wastes, commercial reactor and fuel-cycle facility decommissioning wastes, and mixed (hazardous and radioactive) low-level waste. For most of these categories, current and projected inventories are given the calendar-year 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions. In addition, characteristics and current inventories are reported for miscellaneous radioactive materials that may require geologic disposal. 256 refs., 38 figs., 141 tabs.

  6. Integrated data base for 1993: US spent fuel and radioactive waste inventories, projections, and characteristics. Revision 9

    Energy Technology Data Exchange (ETDEWEB)

    Klein, J.A.; Storch, S.N.; Ashline, R.C. [and others

    1994-03-01

    The Integrated Data Base (IDB) Program has compiled historic data on inventories and characteristics of both commercial and DOE spent fuel; also, commercial and U.S. government-owned radioactive wastes through December 31, 1992. These data are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest U.S. Department of Energy/Energy Information Administration (DOE/EIA) projections of U.S. commercial nuclear power growth and the expected DOE-related and private industrial and institutional (I/I) activities. The radioactive materials considered, on a chapter-by-chapter basis, are spent nuclear fuel, high-level waste (HLW), transuranic (TRU), waste, low-level waste (LLW), commercial uranium mill tailings, environmental restoration wastes, commercial reactor and fuel-cycle facility decommissioning wastes, and mixed (hazardous and radioactive) LLW. For most of these categories, current and projected inventories are given through the calendar-year (CY) 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions. In addition, characteristics and current inventories are reported for miscellaneous radioactive materials that may require geologic disposal.

  7. Integrated Data Base for 1992: US spent fuel and radioactive waste inventories, projections, and characteristics. Revision 8

    Energy Technology Data Exchange (ETDEWEB)

    Payton, M. L.; Williams, J. T.; Tolbert-Smith, M.; Klein, J. A.

    1992-10-01

    The Integrated Data Base (IDB) Program has compiled current data on inventories and characteristics of commercial spent fuel and both commercial and US government-owned radioactive wastes through December 31, 1991. These data are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest US Department of Energy/Energy Information Administration (DOE/EIA) projections of US commercial nuclear power growth and the expected DOE-related and private industrial and institutional (I/I) activities. The radioactive materials considered, on a chapter-by-chapter basis, are spent nuclear fuel, high-level waste, transuranic waste, low-level waste, commercial uranium mill tailings, environmental restoration wastes, commercial reactor and fuel cycle facility decommissioning wastes, and mixed (hazardous and radioactive) low-level waste. For most of these categories, current and projected inventories are given through the year 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions. In addition, characteristics and current inventories are reported for miscellaneous radioactive materials that may require geologic disposal.

  8. LUMINEU: a search for neutrinoless double beta decay based on ZnMoO$_4$ scintillating bolometers

    CERN Document Server

    Armengaud, E; Augier, C; Benoit, A; Berge, L; Boiko, R S; Bergmann, T; Blumer, J; Broniatowski, A; Brudanin, V; Camus, P; Cazes, A; Chapellier, M; Charlieux, F; Chernyak, D M; Coron, N; Coulter, P; Danevich, F A; de Boissiere, T; Decourt, R; De Jesus, M; Devoyon, L; Drillien, A -A; Dumoulin, L; Eitel, K; Enss, C; Filosofov, D; Fleischmann, A; Foerster, N; Fourches, N; Gascon, J; Gastaldo, L; Gerbier, G; Giuliani, A; Gray, D; Gros, M; Hehn, L; Henry, S; Herve, S; Heuermann, G; Humbert, V; Ivanov, I M; Juillard, A; Kefelian, C; Kleifges, M; Kluck, H; Kobychev, V V; Koskas, F; Kozlov, V; Kraus, H; Kudryavtsev, V A; Sueur, H Le; Loidl, M; Magnier, P; Makarov, E P; Mancuso, M; de Marcillac, P; Marnieros, S; Marrache-Kikuchi, C; Menshikov, A; Nasonov, S G; Navick, X -F; Nones, C; Olivieri, E; Pari, P; Paul, B; Penichot, Y; Pessina, G; Piro, M C; Plantevin, O; Poda, D V; Redon, T; Robinson, M; Rodrigues, M; Rozov, S; Sanglard, V; Schmidt, B; Shlegel, S Scorza V N; Siebenborn, B; Strazzer, O; Tcherniakhovski, D; Tenconi, M; Torres, L; Tretyak, V I; Vagneron, L; Vasiliev, Ya V; Velazquez, M; Viraphong, O; Walker, R J; Weber, M; Yakushev, E; Zhang, X; Zhdankov, V N

    2016-01-01

    The LUMINEU is designed to investigate the possibility to search for neutrinoless double beta decay in $^{100}$Mo by means of a large array of scintillating bolometers based on ZnMoO$_4$ crystals enriched in $^{100}$Mo. High energy resolution and relatively fast detectors, which are able to measure both the light and the heat generated upon the interaction of a particle in a crystal, are very promising for the recognition and rejection of background events. We present the LUMINEU concepts and the experimental results achieved aboveground and underground with large-mass natural and enriched crystals. The measured energy resolution, the $\\alpha/\\beta$ discrimination power and the radioactive internal contamination are all within the specifications for the projected final LUMINEU sensitivity. Simulations and preliminary results confirm that the LUMINEU technology can reach zero background in the region of interest (around 3 MeV) with exposures of the order of hundreds kg$\\times$years, setting the bases for a nex...

  9. [Estimation of cost-saving for reducing radioactive waste from nuclear medicine facilities by implementing decay in storage (DIS) in Japan].

    Science.gov (United States)

    Kida, Tetsuo; Hiraki, Hitoshi; Yamaguchi, Ichirou; Fujibuchi, Toshioh; Watanabe, Hiroshi

    2012-01-01

    DIS has not yet been implemented in Japan as of 2011. Therefore, even if risk was negligible, medical institutions have to entrust radioactive temporal waste disposal to Japan Radio Isotopes Association (JRIA) in the current situation. To decide whether DIS should be implemented in Japan or not, cost-saving effect of DIS was estimated by comparing the cost that nuclear medical facilities pay. By implementing DIS, the total annual cost for all nuclear medical facilities in Japan is estimated to be decreased to 30 million yen or less from 710 million yen. DIS would save 680 million yen (96%) per year.

  10. Radon adsorbed in activated charcoal—a simple and safe radiation source for teaching practical radioactivity in schools and colleges

    Science.gov (United States)

    Al-Azmi, Darwish; Mustapha, Amidu O.; Karunakara, N.

    2012-07-01

    Simple procedures for teaching practical radioactivity are presented in a way that attracts students' attention and does not make them apprehensive about their safety. The radiation source is derived from the natural environment. It is based on the radioactivity of radon, a ubiquitous inert gas, and the adsorptive property of activated charcoal. Radon gas from ambient air in the laboratory was adsorbed into about 70 g of activated charcoal inside metallic canisters. Gamma radiation was subsequently emitted from the canisters, following the radioactive decay of radon and its progenies. The intensities of the emitted gamma-rays were measured at suitable intervals using a NaI gamma-ray detector. The counts obtained were analysed and used to demonstrate the radioactive decay law and determine the half-life of radon. In addition to learning the basic properties of radioactivity the students also get practical experience about the existence of natural sources of radiation in the environment.

  11. Photon and decay data libraries for ORIGEN2 code based on JENDL FP decay data file 2000

    CERN Document Server

    Katakura, J I

    2002-01-01

    Photon and decay data libraries for the ORIGEN2 code have been updated by using JENDL FP Decay Data File 2000 (JENDL/FPD-00). As for the decay data, half-lives, branching ratios and recoverable energy values have been replaced with those of the JENDL/FPD-00 file. The data of the photon library has been also replaced with those of the JENDL/FPD-00 file in which photon data of the nuclides without measured data are calculated with a theoretical method. Using the updated photon library, the calculation of photon spectrum at a short time after fission event is able to be made.

  12. Photon and decay data libraries for ORIGEN2 code based on JENDL FP decay data file 2000

    Energy Technology Data Exchange (ETDEWEB)

    Katakura, Jun-ichi; Yanagisawa, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-11-01

    Photon and decay data libraries for the ORIGEN2 code have been updated by using JENDL FP Decay Data File 2000 (JENDL/FPD-00). As for the decay data, half-lives, branching ratios and recoverable energy values have been replaced with those of the JENDL/FPD-00 file. The data of the photon library has been also replaced with those of the JENDL/FPD-00 file in which photon data of the nuclides without measured data are calculated with a theoretical method. Using the updated photon library, the calculation of photon spectrum at a short time after fission event is able to be made. (author)

  13. MIRD radionuclide data and decay schemes

    CERN Document Server

    Eckerman, Keith F

    2007-01-01

    For all physicians, scientists, and physicists working in the nuclear medicine field, the MIRD: Radionuclide Data and Decay Schemes updated edition is an essential sourcebook for radiation dosimetry and understanding the properties of radionuclides. Includes CD Table of Contents Decay schemes listed by atomic number Radioactive decay processes Serial decay schemes Decay schemes and decay tables This essential reference for nuclear medicine physicians, scientists and physicists also includes a CD with tabulations of the radionuclide data necessary for dosimetry calculations.

  14. Evolution of cement based materials in a repository for radioactive waste and their chemical barrier function

    Energy Technology Data Exchange (ETDEWEB)

    Kienzler, Bernhard; Metz, Volker; Schlieker, Martina; Bohnert, Elke [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany). Inst. fuer Nukleare Entsorgung (INE)

    2015-07-01

    The use of cementitious materials in nuclear waste management is quite widespread. It covers the solidification of low/intermediate-level liquid as well as solid wastes (e.g. laboratory wastes) and serves as shielding. For both high-level and intermediate-low level activity repositories, cement/concrete likewise plays an important role. It is used as construction material for underground and surface disposals, but more importantly it serves as barrier or sealing material. For the requirements of waste conditioning, special cement mixtures have been developed. These include special mixtures for the solidification of evaporator concentrates, borate binding additives and for spilling solid wastes. In recent years, low-pH cements were strongly discussed especially for repository applications, e.g. (Celine CAU DIT COUMES 2008; Garcia-Sineriz, et al. 2008). Examples for relevant systems are Calcium Silicate Cements (ordinary Portland cement (OPC) based) or Calcium Aluminates Cements (CAC). Low-pH pore solutions are achieved by reduction of the portlandite content by partial substitution of OPC by mineral admixtures with high silica content. The blends follow the pozzolanic reaction consuming Ca(OH){sub 2}. Potential admixtures are silica fume (SF) and fly ashes (FA). In these mixtures, super plasticizers are required, consisting of polycarboxilate or naphthalene formaldehyde as well as various accelerating admixtures (Garcia-Sineriz, et al. 2008). The pH regime of concrete/cement materials may stabilize radionuclides in solution. Newly formed alteration products retain or release radionuclides. An important degradation product of celluloses in cement is iso-saccharin acid. According to Glaus 2004 (Glaus and van Loon 2004), it reacts with radionuclides forming dissolved complexes. Apart from potentially impacting radionuclide solubility limitations, concrete additives, radionuclides or other strong complexants compete for surface sites for sorbing onto cement phases. In

  15. Model-Based Detection of Radioactive Contraband for Harbor Defense Incorporating Compton Scattering Physics

    Energy Technology Data Exchange (ETDEWEB)

    Candy, J V; Chambers, D H; Breitfeller, E F; Guidry, B L; Verbeke, J M; Axelrod, M A; Sale, K E; Meyer, A M

    2010-03-02

    The detection of radioactive contraband is a critical problem is maintaining national security for any country. Photon emissions from threat materials challenge both detection and measurement technologies especially when concealed by various types of shielding complicating the transport physics significantly. This problem becomes especially important when ships are intercepted by U.S. Coast Guard harbor patrols searching for contraband. The development of a sequential model-based processor that captures both the underlying transport physics of gamma-ray emissions including Compton scattering and the measurement of photon energies offers a physics-based approach to attack this challenging problem. The inclusion of a basic radionuclide representation of absorbed/scattered photons at a given energy along with interarrival times is used to extract the physics information available from the noisy measurements portable radiation detection systems used to interdict contraband. It is shown that this physics representation can incorporated scattering physics leading to an 'extended' model-based structure that can be used to develop an effective sequential detection technique. The resulting model-based processor is shown to perform quite well based on data obtained from a controlled experiment.

  16. Trapping radioactive ions

    CERN Document Server

    Kluge, Heinz-Jürgen

    2004-01-01

    Trapping devices for atomic and nuclear physics experiments with radioactive ions are becoming more and more important at accelerator facilities. While about ten years ago only one online Penning trap experiment existed, namely ISOLTRAP at ISOLDE/CERN, meanwhile almost every radioactive beam facility has installed or plans an ion trap setup. This article gives an overview on ion traps in the operation, construction or planing phase which will be used for fundamental studies with short-lived radioactive nuclides such as mass spectrometry, laser spectroscopy and nuclear decay spectroscopy. In addition, this article summarizes the use of gas cells and radiofrequency quadrupole (Paul) traps at different facilities as a versatile tool for ion beam manipulation like retardation, cooling, bunching, and cleaning.

  17. Marked disequilibrium between {sup 234}Th and {sup 230}Th of the {sup 238}U natural radioactive decay chain in IAEA reference materials n. 312, 313 and 314

    Energy Technology Data Exchange (ETDEWEB)

    Colaianni, A. [Dipartimento di Geologia e Geofisica dell' Universita di Bari, Via Orabona, 4 - 70125 Bari (Italy); I.N.F.N. Sezione di Bari, Via G. Amendola, 173 - 70126 Bari (Italy); D' Erasmo, G. [Dipartimento Interateneo di Fisica dell' Universita di Bari, Via G. Amendola, 173 - 70126 Bari (Italy); I.N.F.N. Sezione di Bari, Via G. Amendola, 173 - 70126 Bari (Italy); Pantaleo, A., E-mail: pantaleo@ba.infn.i [I.N.F.N. Sezione di Bari, Via G. Amendola, 173 - 70126 Bari (Italy); Schiavulli, L. [Dipartimento Interateneo di Fisica dell' Universita di Bari, Via G. Amendola, 173 - 70126 Bari (Italy); I.N.F.N. Sezione di Bari, Via G. Amendola, 173 - 70126 Bari (Italy)

    2011-02-15

    A new laboratory for the spectroscopy of natural radioactivity with a good energy resolution is presented. It consists of two distinct parts equipped, respectively, the first one with a HpGe {gamma}-ray detector, whose setup has been already completed, and the second one with large area Silicon {alpha}-ray detectors and a radiochemical section for thin {alpha}-samples preparation, whose setup is yet in progress and will be the argument of a separate work. The {gamma}-ray spectrometer was calibrated by means of IAEA Reference Materials n. 312, 313, 314 and 375. A large difference from the predictions of secular equilibrium emerged between the activities of {sup 234}Th and {sup 230}Th in Materials n. 312, 313 and 314.

  18. Marked disequilibrium between 234Th and 230Th of the 238U natural radioactive decay chain in IAEA reference materials n. 312, 313 and 314.

    Science.gov (United States)

    Colaianni, A; D'Erasmo, G; Pantaleo, A; Schiavulli, L

    2011-02-01

    A new laboratory for the spectroscopy of natural radioactivity with a good energy resolution is presented. It consists of two distinct parts equipped, respectively, the first one with a HpGe γ-ray detector, whose setup has been already completed, and the second one with large area Silicon α-ray detectors and a radiochemical section for thin α-samples preparation, whose setup is yet in progress and will be the argument of a separate work. The γ-ray spectrometer was calibrated by means of IAEA Reference Materials n. 312, 313, 314 and 375. A large difference from the predictions of secular equilibrium emerged between the activities of (234)Th and (230)Th in Materials n. 312, 313 and 314.

  19. Traditional blood irradiation facilities based on radioactive sources are phased out; Tradisjonelle blodbestraalingsanlegg basert paa radioaktive kilder fases ut

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-03-01

    Blood irradiation facilities containing radioactive sources are among the most powerful sources of radiation. As government we want to phase out this type of facility for the benefit of virtually risk-free blood irradiation facility based on X-ray technology.(eb)

  20. In-trap decay spectroscopy for {beta}{beta} decays

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, Thomas

    2011-01-18

    The presented work describes the implementation of a new technique to measure electron-capture (EC) branching ratios (BRs) of intermediate nuclei in {beta}{beta} decays. This technique has been developed at TRIUMF in Vancouver, Canada. It facilitates one of TRIUMF's Ion Traps for Atomic and Nuclear science (TITAN), the Electron Beam Ion Trap (EBIT) that is used as a spectroscopy Penning trap. Radioactive ions, produced at the radioactive isotope facility ISAC, are injected and stored in the spectroscopy Penning trap while their decays are observed. A key feature of this technique is the use of a strong magnetic field, required for trapping. It radially confines electrons from {beta} decays along the trap axis while X-rays, following an EC, are emitted isotropically. This provides spatial separation of X-ray and {beta} detection with almost no {beta}-induced background at the X-ray detector, allowing weak EC branches to be measured. Furthermore, the combination of several traps allows one to isobarically clean the sample prior to the in-trap decay spectroscopy measurement. This technique has been developed to measure ECBRs of transition nuclei in {beta}{beta} decays. Detailed knowledge of these electron capture branches is crucial for a better understanding of the underlying nuclear physics in {beta}{beta} decays. These branches are typically of the order of 10{sup -5} and therefore difficult to measure. Conventional measurements suffer from isobaric contamination and a dominating {beta} background at theX-ray detector. Additionally, X-rays are attenuated by the material where the radioactive sample is implanted. To overcome these limitations, the technique of in-trap decay spectroscopy has been developed. In this work, the EBIT was connected to the TITAN beam line and has been commissioned. Using the developed beam diagnostics, ions were injected into the Penning trap and systematic studies on injection and storage optimization were performed. Furthermore, Ge

  1. Study of proton radioactivities

    Energy Technology Data Exchange (ETDEWEB)

    Davids, C.N.; Back, B.B.; Henderson, D.J. [and others

    1995-08-01

    About a dozen nuclei are currently known to accomplish their radioactive decay by emitting a proton. These nuclei are situated far from the valley of stability, and mark the very limits of existence for proton-rich nuclei: the proton drip line. A new 39-ms proton radioactivity was observed following the bombardment of a {sup 96}Ru target by a beam of 420-MeV {sup 78}Kr. Using the double-sided Si strip detector implantation system at the FMA, a proton group having an energy of 1.05 MeV was observed, correlated with the implantation of ions having mass 167. The subsequent daughter decay was identified as {sup 166}Os by its characteristic alpha decay, and therefore the proton emitter is assigned to the {sup 167}Ir nucleus. Further analysis showed that a second weak proton group from the same nucleus is present, indicating an isomeric state. Two other proton emitters were discovered recently at the FMA: {sup 171}Au and {sup 185}Bi, which is the heaviest known proton radioactivity. The measured decay energies and half-lives will enable the angular momentum of the emitted protons to be determined, thus providing spectroscopic information on nuclei that are beyond the proton drip line. In addition, the decay energy yields the mass of the nucleus, providing a sensitive test of mass models in this extremely proton-rich region of the chart of the nuclides. Additional searches for proton emitters will be conducted in the future, in order to extend our knowledge of the location of the proton drip line.

  2. Beta-Decay Study of ^{150}Er, ^{152}Yb, and ^{156}Yb: Candidates for a Monoenergetic Neutrino Beam Facility

    Energy Technology Data Exchange (ETDEWEB)

    Estevez Aguado, M. E. [CSIC-Universidad de Valencia; Algora, A. [CSIC-Universidad de Valencia; Rubio, B. [CSIC-Universidad de Valencia; Bernabeu, J. [CSIC-Universidad de Valencia; Nacher, E. [CSIC-Universidad de Valencia; Tain, J. L. [CSIC-Universidad de Valencia; Gadea, A. [CSIC-Universidad de Valencia; Agramunt, J. [CSIC-Universidad de Valencia; Burkard, K. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Hueller, W. [GSI-Hemholtzzentrum fur Schwerionenforschung, Darmstadt, Germany; Doring, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kirchner, R. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Mukha, I. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Plettner, C. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Roeckl, E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Grawe, H. [GSI-Hemholtzzentrum fur Schwerionenforschung, Darmstadt, Germany; Collatz, R. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Hellstrom, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Cano-Ott, D. [CIEMAT, Madrid; Karny, M. [University of Warsaw; Janas, Z. [University of Warsaw; Gierlik, M. [University of Warsaw; Plochocki, A. [University of Warsaw; Rykaczewski, Krzysztof Piotr [ORNL; Batist, L. [Petersburg Nuclear Physics Institute, Gatchina, Russia; Moroz, F. [Petersburg Nuclear Physics Institute, Gatchina, Russia; Wittman, V. [Petersburg Nuclear Physics Institute, Gatchina, Russia; Blazhev, A. [University of Cologne; Valiente, J. J. [INFN, Laboratori Nazionali di Legnaro, Italy; Espinoza, C. [CFPT-IST, Lisbon

    2011-01-01

    The beta decays of ^{150}Er, ^{152}Yb, and ^{156}Yb nuclei are investigated using the total absorption spectroscopy technique. These nuclei can be considered possible candidates for forming the beam of a monoenergetic neutrino beam facility based on the electron capture (EC) decay of radioactive nuclei. Our measurements confirm that for the cases studied, the EC decay proceeds mainly to a single state in the daughter nucleus.

  3. Predicted halflives for cluster radioactivities

    Energy Technology Data Exchange (ETDEWEB)

    Poenaru, D.N. (Institutul Central de Fizica, Bucharest (Romania); Frankfurt Univ. (Germany, F.R.). Inst. fuer Theoretische Physik); Greiner, W. (Frankfurt Univ. (Germany, F.R.). Inst. fuer Theoretische Physik); Ivascu, M. (Institutul Central de Fizica, Bucharest (Romania))

    1989-10-09

    The main results of the analytical superasymmetric fission model, describing in a unified manner cluster radioactivities, alpha-decay and cold fission processes, are briefly reviewed. Predicted halflives for {sup 14}C, {sup 24,25,26}Ne, {sup 28,30}Mg and {sup 32}Si radioactivities in the range 10{sup 11}-10{sup 26} s and the corresponding branching ratios relative to {alpha}-decay 10{sup -16}-10{sup -9} have been experimentally confirmed within 1.5 orders of magnitude. (orig.).

  4. Radioactive Material

    CERN Multimedia

    2004-01-01

    The Radiation Protection Group of the Safety Commission is responsible for shipping of radioactive material from CERN to any external institute or organisation. The RP group is equally responsible for the reception of radioactive material shipped to any of the CERN sites. Anyone who needs to ship from or import into CERN radioactive material must contact the Radioactive Shipping Service of the RP group in advance. Instructions are available at: http://cern.ch/rp-shipping or in the Radiation Protection Procedure PRP13: https://edms.cern.ch/document/346823 Radiation Protection Group

  5. 氟保护剂预防鼻咽癌放疗后放射性龋齿的临床研究%Preventive Effect of Fluor Protector for Radioactive Decay in the Radiotherapy of Nasopharynx Cancer

    Institute of Scientific and Technical Information of China (English)

    余雅云; 王根桃

    2016-01-01

    Objective To explore the preventive effect of fluor protector for radioactive decay in the radiotherapy of nasopharynx cancer Methods The 112 patients with nasopharynx cancer received radiotherapy were divided into the fluor protector group and the sodium chloride group by self-control method The test began in 1,3,5 d before radiotherapy Fluor protector and sodium chloride were coated on the tooth surface after cleaning,disinfecting and drying the tooth surface every time The decayed-missing-filled tooth(DMFT)and decayed-missing-filled surface (DMFS)were examined before and one year after the radiotherapy Results Before the radiotherapy,the DMFT and DMFS of the two groups showed no significant difference(P > 0 05) However,one year after the radiothera-py,DMFT and DMFS of the two groups increased significantly(P < 0 05)and more increase was found in the so-dium chloride group(P < 0 05) The DMFT and DMFS of the sodium chloride group were more greater than those of the fluor protector group(P < 0 05)Conclusion Fluor protector could significantly reduce the occurrence of radioactive decay in the radiotherapy of nasopharynx cancer.%目的:探讨鼻咽癌患者放疗前牙面用氟保护剂预防放疗后放射性龋齿的效果。方法选择首次接受放疗的鼻咽癌患者112例,采用自身对照方法分为氟保护剂组和生理盐水组。在放疗前1、3、5 d 开始试验,每次清洁牙面,消毒干燥后,用小毛刷将氟保护剂涂抹在一侧牙面(氟保护剂组),同时将生理盐水涂抹在另一侧牙面(生理盐水组),观察并记录放疗前和放疗后1 a 2组的龋失补牙数(DMFT)和龋失补牙面数(DMFS)。结果放疗前,氟保护剂组和生理盐水组 DMFT 和 DMFS 比较差异均无统计学意义( P 均>005)。与放疗前比较,2组 DMFT 和 DMFS 在放疗后1 a 均明显升高(P 均<005),但生理盐水组 DMFT 和DMFS 升高更为明显,且生理盐水组 DMFT 和 DMFS 明

  6. Enhanced control of DFIG wind turbine based on stator flux decay compensation

    DEFF Research Database (Denmark)

    Zhu, Rongwu; Deng, Fujin; Chen, Zhe;

    2016-01-01

    For the doubly-fed induction generator (DFIG)- based wind energy conversion system (WECS), the decaying flux and negative flux are the main reasons to cause the DFIG rotor overcurrent, during grid faults. The stator decaying flux characteristics versus the depth and instant of the stator voltage...... is significantly reduced during grid faults. The experimental results based on the 7.5 kW DFIG setup is carried to validate the correctness and feasibility of the proposed strategy. Dynamic voltage restorer (DVR) can be one of the applications. With the proposed strategy, the DVR only works in a half fundamental...... period and its output voltage amplitude is half of the stator voltage variation, during the grid voltage drop and recovery, respectively. As a consequence, the DVR can be rated for lower power saving cost. The simulation results based on Matlab/Simulink using a 2 MW DFIG and the experimental results...

  7. An explanation of the "negative neutrino mass squared" anomaly in tritium $ \\beta$-decay based on a theory of mass

    CERN Document Server

    Ingraham, R L; Wilkes, J M

    2000-01-01

    A proposed solution of the anomalous behavior of the electron spectrum near the endpoint of tritium $\\beta$-decay is offered. It is based on a new theory of mass in which mass becomes a dynamical variable, and the electron in the tritium $\\beta$-decay has a narrow mass distribution. The predicted Kurie plots explain the main feature (``$m_{\

  8. Criteria for evaluation of building materials hazard based on their natural radioactivity in Russia and in the European Union countries

    Directory of Open Access Journals (Sweden)

    Buzina Darya

    2016-01-01

    Full Text Available We hereby have considered the natural radioactivity of building materials as a source of radiation for the human environment. We have considered the Russian and the European evaluation criteria for ensuring radiation safety of the population. We also present an experimental research of the content of natural radionuclides in building materials. We have calculated the effective specific activity and the activity concentration index based on the results presented. We have identified discrepancies between the Russian and the European standards.

  9. International workshop on scientific bases for decision making after a radioactive contamination of an urban environment. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    This workshop aims to discuss the most important aspects of scientific bases for decision making after a radioactive contamination in urban environment and to identify some scientific, social and economic open questions. Papers explaining in more details the principles of intervention, computational capabilities and measurements after a contamination of urban areas are presented. A review on practical experiences from Chernobyl and Goiania accidents is also included.

  10. Experimental Verification on Remote Detectability of Concealed Radioactive Material Based on the Plasma Discharge Delay Time using High-Power Millimeter-Wave

    Science.gov (United States)

    Kim, Dongsung; Yu, Dongho; Sawant, Ashwini; Choe, Mun Seok; Lee, Ingeun; Choi, Eunmi

    2016-10-01

    We experimentally demonstrate a remote detection method of a radioactive source by plasma breakdown using high-power millimeter-wave source, gyrotron. A number of free electrons near the radioactive source are much higher than those of without the radioactive source (roughly 10 particles/cm3) owing to the interaction of air molecules and strong gamma rays generated by radioactive material. The RF wave beam is focused in ambient air, and the plasmas discharge occurs involving random delay time which means a time interval between the RF wave and a fluorescent light caused by the plasma. We observed that the delay time decreased significantly due to the high density of free electrons in Ar plasma with an existence of Co60 radioactive material. This technique of delay time measurement shows 1000 times more sensitive than a method of detectable mass equation to identify the existence of radioactive source remotely. It is the first experimental verification of radioactive material detection using a high power gyrotron. This study shows that a remote detection of radioactive material based on analysis of precise delay time measurement could be feasible by using a high power millimeter/THz wave gyrotron. NRF-2013R1A1A2061062, NRF-2012-Global Ph.D. Fellowship Program.

  11. Search for lost or orphan radioactive sources based on Nal gamma spectrometry

    DEFF Research Database (Denmark)

    Aage, Helle Karina; Korsbech, Uffe C C

    2003-01-01

    Within recent decades many radioactive sources have been lost, stolen, or abandoned, and some have caused contamination or irradiation of people. Therefore reliable methods for source recovery are needed. The use of car borne NaI(Tl) detectors is discussed. Standard processing of spectra in general...

  12. Simulated Radioactivity

    Science.gov (United States)

    Boettler, James L.

    1972-01-01

    Describes the errors in the sugar-cube experiment related to radioactivity as described in Project Physics course. The discussion considers some of the steps overlooked in the experiment and generalizes the theory beyond the sugar-cube stage. (PS)

  13. Concentrating Radioactivity

    Science.gov (United States)

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  14. 5He radioactivity

    OpenAIRE

    Poenaru, D.N.; Ivaşcu, M.

    1984-01-01

    The disintegration of a metastable nuclear state by emission of a light particle can be considered to be a very asymmetric fission process. An approximation of the potential barrier in the overlapping region of the two fragments leads to an analytic relationship for the life-time, allowing us to handle a large number of cases to search for new kinds of radioactivities. In this way, it is predicted that some nuclei with Z = 83-92, N = 127-137 and 97-105,145-157 are able to decay spontaneously ...

  15. Radioactivity, radionuclides, radiation

    CERN Document Server

    Magill, Joseph

    2005-01-01

    RADIOACTIVITY – RADIONUCLIDES – RADIATION is suitable for a general audience interested in topical environmental and human health radiological issues such as radiation exposure in aircraft, food sterilisation, nuclear medicine, radon gas, radiation dispersion devices ("dirty bombs")… It leads the interested reader through the three Rs of nuclear science, to the forefront of research and developments in the field. The book is also suitable for students and professionals in the related disciplines of nuclear and radiochemistry, health physics, environmental sciences, nuclear and astrophysics. Recent developments in the areas of exotic decay modes (bound beta decay of ‘bare’ or fully ionized nuclei), laser transmutation, nuclear forensics, radiation hormesis and the LNT hypothesis are covered. Atomic mass data for over 3000 nuclides from the most recent (2003) evaluation are included.

  16. Radioactive liquid wastes discharged to ground in the 200 Areas during 1976

    Energy Technology Data Exchange (ETDEWEB)

    Mirabella, J.E.

    1977-05-09

    An overall summary is presented giving the radioactive liquid wastes discharged to ground during 1976 and since startup (for both total and decayed depositions) within the Production and Waste Management Division control zone (200 Area plateau). Overall summaries are also presented for 200 East Area and for 200 West Area. The data contain an estimate of the radioactivity discharged to individual ponds, cribs and specific retention sites within the Production and Waste Management Division during 1976 and from startup through December 31, 1976; an estimate of the decayed activities from startup through 1976; the location and reference drawings of each disposal site; and the usage dates of each disposal site. The estimates for the radioactivity discharged and for decayed activities dicharged from startup through December 31, 1976 are based upon Item 4 of the Bibliography. The volume of liquid discharged to the ponds also includes major nonradioactive streams. The wastes discharged during 1976 to each active disposal site are detailed on a month-to-month basis, along with the monthly maximum concentration and average concentration data. An estimate of the radioactivity discharged to each active site along with the remaining decayed activities is given.

  17. Development programs in the United States of America for the application of cement-based grouts in radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)

    Dole, L.R.; Row, T.H.

    1984-01-01

    This paper briefly reviews seven cement-based waste form development programs at six of the US Department of Energy (DOE) sites. These sites have developed a variety of processes that range from producing 25 mm (1 in.) diameter pellets in a glove box to producing 240 m (800 ft.) diameter grout sheets within the bedding planes of a deep shale formation. These successful applications of cement-based waste forms to the many radioactive waste streams from nuclear facilities bear witness to the flexibility and reliability of this class of materials. This paper also discusses the major issues regarding the application of cement-based waste forms to radioactive waste management problems. These issues are (1) leachability, (2) radiation stability, (3) thermal stability, (4) phase complexity of the matrix, and (5) effects of the waste stream composition. A cursory review of current research in each of these areas is given This paper also discusses future trends in cement-based waste form development and applications. 31 references, 11 figures.

  18. Simulation for thick-target yields of transmutation reactions on radioactive targets, based on inverse kinematics

    Science.gov (United States)

    Ebata, Shuichiro; Aikawa, Masayuki; Imai, Shotaro

    2016-06-01

    To dispose of long-lived fission products (LLFP) ejected from nuclear reactor plants is one of the most important tasks on nuclear physics and engineering. The experiments with the radiative target are limited, due to the high radioactivity and chemical property of the target. In consequence, the nuclear reaction data for LLFP are insufficient. In this work, we propose a feasible method to obtain the data for radiative targets using inverse kinematics and simulate specific systems to evaluate the thick-target yields of the nuclear transmutation reactions for LLFP.

  19. Simulation for thick-target yields of transmutation reactions on radioactive targets, based on inverse kinematics

    Directory of Open Access Journals (Sweden)

    Ebata Shuichiro

    2016-01-01

    Full Text Available To dispose of long-lived fission products (LLFP ejected from nuclear reactor plants is one of the most important tasks on nuclear physics and engineering. The experiments with the radiative target are limited, due to the high radioactivity and chemical property of the target. In consequence, the nuclear reaction data for LLFP are insufficient. In this work, we propose a feasible method to obtain the data for radiative targets using inverse kinematics and simulate specific systems to evaluate the thick-target yields of the nuclear transmutation reactions for LLFP.

  20. Constraint-Based Routing Models for the Transport of Radioactive Materials

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Steven K [ORNL

    2015-01-01

    The Department of Energy (DOE) has a historic programmatic interest in the safe and secure routing, tracking, and transportation risk analysis of radiological materials in the United States. In order to address these program goals, DOE has funded the development of several tools and related systems designed to provide insight to planners and other professionals handling radioactive materials shipments. These systems include the WebTRAGIS (Transportation Routing Analysis Geographic Information System) platform. WebTRAGIS is a browser-based routing application developed at Oak Ridge National Laboratory (ORNL) focused primarily on the safe transport of spent nuclear fuel from US nuclear reactors via railway, highway, or waterway. It is also used for the transport planning of low-level radiological waste to depositories such as the Waste Isolation Pilot Plant (WIPP) facility. One particular feature of WebTRAGIS is its coupling with high-resolution population data from ORNL s LandScan project. This allows users to obtain highly accurate population count and density information for use in route planning and risk analysis. To perform the routing and risk analysis WebTRAGIS incorporates a basic routing model methodology, with the additional application of various constraints designed to mimic US Department of Transportation (DOT), DOE, and Nuclear Regulatory Commission (NRC) regulations. Aside from the routing models available in WebTRAGIS, the system relies on detailed or specialized modal networks for the route solutions. These include a highly detailed network model of the US railroad system, the inland and coastal waterways, and a specialized highway network that focuses on the US interstate system and the designated hazardous materials and Highway Route Controlled Quantity (HRCQ) -designated roadways. The route constraints in WebTRAGIS rely upon a series of attributes assigned to the various components of the different modal networks. Routes are determined via a

  1. Decay constants in geochronology

    Institute of Scientific and Technical Information of China (English)

    IgorM.Villa; PaulR.Renne

    2005-01-01

    Geologic time is fundamental to the Earth Sciences, and progress in many disciplines depends critically on our ability to measure time with increasing accuracy and precision. Isotopic geochronology makes use of the decay of radioactive nuclides as a help to quantify the histories of rock, minerals, and other materials. Both accuracy and precision of radioisotopic ages are, at present, limited by those of radioactive decay constants. Modem mass spectrometers can measure isotope ratios with a precision of 10-4 or better. On the other hand, the uncertainties associated with direct half-life determinations are, in most cases, still at the percent level. The present short note briefly summarizes progress and problems that have been encountered during the Working Group's activity.

  2. Soot particle sizing based on analytical formula derived from laser-induced incandescence decay signals

    Science.gov (United States)

    Wu, Jian; Chen, Linghong; Yan, Mingming; Wu, Xuecheng; Gréhan, Gérard; Cen, Kefa

    2017-01-01

    The laser-induced incandescence (LII) signal during a heat-conduction-dominated cooling process was used to derive an analytical formula to describe the relationship between the soot particle size and the LII signal decay time by exponential fitting. The formula was used to determine particle sizes based on the experimental LII signals at different detection wavelengths for an atmospheric C2H4/air diffusion flame. The results agree with those obtained from temporal temperature measurements. The measurements and numerical calculations demonstrate that particle sizing depends weakly on the maximum temperature in the formula within a typical heat-up temperature range. The results show that based on this formula, a compact single-color LII detection system can be used for particle sizing with low uncertainty under most practical combustion conditions, at least in cases where heat conduction is dominant and occurs in a free molecular regime during particle cooling.

  3. Search for bound-state electron+positron pair decay

    Science.gov (United States)

    Bosch, F.; Hagmann, S.; Hillenbrand, P.-M.; Lane, G. J.; Litvinov, Yu. A.; Reed, M. W.; Sanjari, M. S.; Stöhlker, Th.; Torilov, S. Yu.; Tu, X. L.; Walke, P. M.

    2016-09-01

    The heavy ion storage rings coupled to in-flight radioactive-ion beam facilities, namely the ability to produce and store for extended periods of time radioactive nuclides in high atomic charge states, for the searchof yet unobserved decay mode - bound-state electron-positron pair decay.

  4. Systematization of α-decaying nuclei based on shell structures: The case of even-odd nuclei

    Science.gov (United States)

    Yarman, Tolga; Zaim, Nimet; Yarman, O.; Kholmetskii, Alexander; Arık, Metin

    2017-01-01

    Previously, we provided a novel systematization of α-decaying even-even nuclei starting with the classically adopted mechanism (Yarman et al., Eur. Phys. J. A 52, 140 (2016)). The decay half-life of an α-decaying nucleus was framed so that i) the α-particle is taken at the outset to be born inside the parent nucleus with a given probability, ii) where it then keeps on bouncing off of the barrier of the parent nucleus till iii) it finally tunnels through the barrier. Knowing beforehand the measured decay half-life, we have taken into consideration, as a parameter, the probability of the α-particle being first born within the parent before it is emitted. We thence developed a scaffold based on shell properties of families composed of alike even-even nuclei. Nevertheless, our model allows us to incorporate any α-decaying nuclei, and along this line, we present a follow-up systematization of even-odd nuclei, with cases of odd-even and odd-odd α-decaying nuclei pending to be considered in a separate contribution. Notwithstanding, we make an effort herein to expand our approach to investigate the effect of "pairing" ( e.g., when a number of nucleons in the given nucleus becomes an even number, instead of the initial odd number, due to the addition of at least one neutron). Our results show that "pairing", as expected, definitely increases the stability of the given nucleus.

  5. Radioactivity in food crops

    Energy Technology Data Exchange (ETDEWEB)

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

  6. Artificial Intelligence based Solver for Governing Model of Radioactivity Cooling, Self-gravitating Clouds and Clusters of Galaxies

    Directory of Open Access Journals (Sweden)

    Junaid Ali Khan

    2013-06-01

    Full Text Available In this study, a reliable alternate platform is developed based on artificial neural network optimized with soft computing technique for a non-linear singular system that can model complex physical phenomenas of the nature like radioactivity cooling, self-gravitating clouds and clusters of galaxies. The trial solution is mathematically represented by feed-forward neural network. A cost function is defined in an unsupervised manner that is optimized by a probabilistic meta-heuristic global search technique based on annealing in metallurgy. The results of the designed scheme are evaluated by comparing with the desired response of the system. The applicability, stability and reliability of the proposed method is validated by Monte Carlo simulations.

  7. A dynamic CMOS multiplier for analog VLSI based on exponential pulse-decay modulation

    Science.gov (United States)

    Massengill, Lloyd W.

    1991-03-01

    A clocked, charge-based, CMOS modulator circuit is presented. The circuit, which performs a semilinear multiplication function, has applications in arrayed analog VLSI architectures such as parallel filters and neural network systems. The design presented is simple in structure, uses no operational amplifiers for the actual multiplication function, and uses no power in the static mode. Two-quadrant weighting of an input signal is accomplished by control of the magnitude and decay time of an exponential current pulse, resulting in the delivery of charge packets to a shared capacitive summing bus. The cell is modular in structure and can be fabricated in a standard CMOS process. An analytical derivation of the operation of the circuit, SPICE simulations, and MOSIS fabrication results are presented. The simulation studies indicate that the circuit is inherently tolerant to temperature effects, absolute device sizing errors, and clock-feedthrough transients.

  8. Observation of Diproron Decay From Excited States of 28S

    Institute of Scientific and Technical Information of China (English)

    LIN; Cheng-jian; XU; Xin-xing; JIA; Hui-ming; YANG; Feng; WU; Zhen-dong; ZHANG; Huan-qiao; LIU; Zu-hua; YANG; Lei; BAO; Peng-fei; SUN; Li-jie; MA; Nan-ru

    2013-01-01

    The historic discovery of radioactivity by Henri Becquerel in 1896 opened a door to nuclear science.Since then,several types of nuclear decay,like?,?,?decays,fission,one-proton(1p)radioactivity,etc.have been discovered with the development of nuclear physics.The latest,two-proton(2p)radioactivity proposed by Goldanskii more than half century ago has been already observed experimentally in the last

  9. Introduction to naturally occurring radioactive material

    Energy Technology Data Exchange (ETDEWEB)

    Egidi, P.

    1997-08-01

    Naturally occurring radioactive material (NORM) is everywhere; we are exposed to it every day. It is found in our bodies, the food we eat, the places where we live and work, and in products we use. We are also bathed in a sea of natural radiation coming from the sun and deep space. Living systems have adapted to these levels of radiation and radioactivity. But some industrial practices involving natural resources concentrate these radionuclides to a degree that they may pose risk to humans and the environment if they are not controlled. Other activities, such as flying at high altitudes, expose us to elevated levels of NORM. This session will concentrate on diffuse sources of technologically-enhanced (TE) NORM, which are generally large-volume, low-activity waste streams produced by industries such as mineral mining, ore benefication, production of phosphate Fertilizers, water treatment and purification, and oil and gas production. The majority of radionuclides in TENORM are found in the uranium and thorium decay chains. Radium and its subsequent decay products (radon) are the principal radionuclides used in characterizing the redistribution of TENORM in the environment by human activity. We will briefly review other radionuclides occurring in nature (potassium and rubidium) that contribute primarily to background doses. TENORM is found in many waste streams; for example, scrap metal, sludges, slags, fluids, and is being discovered in industries traditionally not thought of as affected by radionuclide contamination. Not only the forms and volumes, but the levels of radioactivity in TENORM vary. Current discussions about the validity of the linear no dose threshold theory are central to the TENORM issue. TENORM is not regulated by the Atomic Energy Act or other Federal regulations. Control and regulation of TENORM is not consistent from industry to industry nor from state to state. Proposed regulations are moving from concentration-based standards to dose-based

  10. A feasibility study of ortho-positronium decays measurement with the J-PET scanner based on plastic scintillators

    Science.gov (United States)

    Kamińska, D.; Gajos, A.; Czerwiński, E.; Alfs, D.; Bednarski, T.; Białas, P.; Curceanu, C.; Dulski, K.; Głowacz, B.; Gupta-Sharma, N.; Gorgol, M.; Hiesmayr, B. C.; Jasińska, B.; Korcyl, G.; Kowalski, P.; Krzemień, W.; Krawczyk, N.; Kubicz, E.; Mohammed, M.; Niedźwiecki, Sz.; Pawlik-Niedźwiecka, M.; Raczyński, L.; Rudy, Z.; Silarski, M.; Wieczorek, A.; Wiślicki, W.; Zgardzińska, B.; Zieliński, M.; Moskal, P.

    2016-08-01

    We present a study of the application of the Jagiellonian positron emission tomograph (J-PET) for the registration of gamma quanta from decays of ortho-positronium (o-Ps). The J-PET is the first positron emission tomography scanner based on organic scintillators in contrast to all current PET scanners based on inorganic crystals. Monte Carlo simulations show that the J-PET as an axially symmetric and high acceptance scanner can be used as a multi-purpose detector well suited to pursue research including e.g. tests of discrete symmetries in decays of ortho-positronium in addition to the medical imaging. The gamma quanta originating from o-Ps decay interact in the plastic scintillators predominantly via the Compton effect, making the direct measurement of their energy impossible. Nevertheless, it is shown in this paper that the J-PET scanner will enable studies of the { o-Ps }→ 3γ decays with angular and energy resolution equal to σ (θ ) ≈ {0.4°} and σ (E) ≈ 4.1 {keV}, respectively. An order of magnitude shorter decay time of signals from plastic scintillators with respect to the inorganic crystals results not only in better timing properties crucial for the reduction of physical and instrumental background, but also suppresses significantly the pile-ups, thus enabling compensation of the lower efficiency of the plastic scintillators by performing measurements with higher positron source activities.

  11. A feasibility study of ortho-positronium decays measurement with the J-PET scanner based on plastic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Kaminska, D.; Gajos, A.; Czerwinski, E.; Alfs, D.; Bednarski, T.; Bialas, P.; Dulski, K.; Glowacz, B.; Gupta-Sharma, N.; Korcyl, G.; Krawczyk, N.; Kubicz, E.; Mohammed, M.; Niedzwiecki, Sz.; Pawlik-Niedzwiecka, M.; Rudy, Z.; Wieczorek, A.; Zielinski, M.; Moskal, P. [Jagiellonian University, Faculty of Physics, Astronomy and Applied Computer Science, Krakow (Poland); Curceanu, C.; Silarski, M. [INFN, Laboratori Nazionali di Frascati, CP 13, Frascati (Italy); Gorgol, M.; Jasinska, B.; Zgardzinska, B. [Maria Curie-Sklodowska University, Department of Nuclear Methods, Institute of Physics, Lublin (Poland); Hiesmayr, B.C. [University of Vienna, Faculty of Physics, Vienna (Austria); Kowalski, P.; Raczynski, L.; Wislicki, W. [Swierk Computing Centre, National Centre for Nuclear Research, Otwock-Swierk (Poland); Krzemien, W. [National Centre for Nuclear Research, High Energy Department, Otwock-Swierk (Poland)

    2016-08-15

    We present a study of the application of the Jagiellonian positron emission tomograph (J-PET) for the registration of gamma quanta from decays of ortho-positronium (o-Ps). The J-PET is the first positron emission tomography scanner based on organic scintillators in contrast to all current PET scanners based on inorganic crystals. Monte Carlo simulations show that the J-PET as an axially symmetric and high acceptance scanner can be used as a multi-purpose detector well suited to pursue research including e.g. tests of discrete symmetries in decays of ortho-positronium in addition to the medical imaging. The gamma quanta originating from o-Ps decay interact in the plastic scintillators predominantly via the Compton effect, making the direct measurement of their energy impossible. Nevertheless, it is shown in this paper that the J-PET scanner will enable studies of the o-Ps → 3γ decays with angular and energy resolution equal to σ(θ) ∼ 0.4 {sup circle} and σ(E) ∼ 4.1 keV, respectively. An order of magnitude shorter decay time of signals from plastic scintillators with respect to the inorganic crystals results not only in better timing properties crucial for the reduction of physical and instrumental background, but also suppresses significantly the pile-ups, thus enabling compensation of the lower efficiency of the plastic scintillators by performing measurements with higher positron source activities. (orig.)

  12. A data base for low-level radioactive waste disposal sites

    Energy Technology Data Exchange (ETDEWEB)

    Daum, M.L.; Moskowitz, P.D.

    1989-07-01

    A computerized database was developed to assist the US Environmental Protection Agency (EPA) in evaluating methods and data for characterizing health hazards associated with land and ocean disposal options for low-level radioactive wastes. The data cover 1984 to 1987. The types of sites considered include Nuclear Regulatory Commission (NRC) licensed commercial disposal sites, EPA National Priority List (NPL) sites, US Department of Energy (DOE) Formerly Utilized Sites Remedial Action Project (FUSRAP) and DOE Surplus Facilities Management Program (SFMP) sites, inactive US ocean disposal sites, and DOE/Department of Defense facilities. Sources of information include reports from EPA, the US Department of Energy (DOE) and the Nuclear Regulatory Commission (NRC), as well as direct communication with individuals associated with specific programs. The data include site descriptions, waste volumes and activity levels, and physical and radiological characterization of low-level wastes. Additional information on mixed waste, packaging forms, and disposal methods were compiled, but are not yet included in the database. 55 refs., 4 figs., 2 tabs.

  13. Project 8: Determining neutrino mass from tritium beta decay using a frequency-based method

    Energy Technology Data Exchange (ETDEWEB)

    Doe, Peter J.; Kofron, Jared N.; MCBride, Lisa; Robertson, R. G. H.; Rosenberg, Leslie; Rybka, Gray; Doelman, S.; Rogers, Alan E.; Formaggio, Joseph; Furse, Daniel; Oblath, Noah S.; LaRoque, Benjamin; Leber, Michelle; Monreal, Ben; Bahr, Matthew; Asner, David M.; Jones, Anthony M.; Fernandes, Justin L.; VanDevender, Brent A.; Patterson, Ryan B.; Bradley, Rich; Thummler, Thomas

    2013-10-04

    A general description is given of Project 8, a new approach to measuring the neutrino mass scale via the beta decay of tritium. In Project 8, the energy of electrons emitted in beta decay is determined from the frequency of cyclotron radiation emitted as the electrons spiral in a uniform magnetic field

  14. A novel approach to the systematization of α-decaying nuclei, based on shell structures

    Science.gov (United States)

    Yarman, Tolga; Zaim, Nimet; Amon Susam, Lidya; Kholmetskii, Alexander; Arık, Metin; Azmi Altıntaş, Ali; Ozaydin, Fatih

    2016-05-01

    We provide a novel systematization of α-decaying nuclei, starting with the classically adopted mechanism. The decay half-life of an α-disintegrating nucleus is framed, supposing that i) the α-particle is born inside the parent, then ii) it keeps on hitting the barrier, while it runs back and forth inside the parent, and hitting each time the barrier, and iii) it finally tunnels through the barrier. One can, knowing the decay half-life, consider the probability that the α-particle is born within the parent, before it is emitted, as a parameter. Under all circumstances, the decay appears to be governed by the shell structure of the given nucleus. Our approach well allows to incorporate (not only even-even nuclei, but) all nuclei, decaying via throwing an alpha particle. Though herein, we limit ourselves with just even-even nuclei, in the aim of comparing our results with the existing Geiger-Nuttal results.

  15. A proposed classification system for high-level and other radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kocher, D. C.; Croff, A. G.

    1987-06-01

    This report presents a proposal for quantitative and generally applicable risk-based definitions of high-level and other radioactive wastes. On the basis of historical descriptions and definitions of high-level waste (HLW), in which HLW has been defined in terms of its source as waste from reprocessing of spent nuclear fuel, we propose a more general definition based on the concept that HLW has two distinct attributes: HLW is (1) highly radioactive and (2) requires permanent isolation. This concept leads to a two-dimensional waste classification system in which one axis, related to ''requires permanent isolation,'' is associated with long-term risks from waste disposal and the other axis, related to ''highly radioactive,'' is associated with shorter-term risks due to high levels of decay heat and external radiation. We define wastes that require permanent isolation as wastes with concentrations of radionuclides exceeding the Class-C limits that are generally acceptable for near-surface land disposal, as specified in the US Nuclear Regulatory Commission's rulemaking 10 CFR Part 61 and its supporting documentation. HLW then is waste requiring permanent isolation that also is highly radioactive, and we define ''highly radioactive'' as a decay heat (power density) in the waste greater than 50 W/m/sup 3/ or an external radiation dose rate at a distance of 1 m from the waste greater than 100 rem/h (1 Sv/h), whichever is the more restrictive. This proposal also results in a definition of Transuranic (TRU) Waste and Equivalent as waste that requires permanent isolation but is not highly radioactive and a definition of low-level waste (LLW) as waste that does not require permanent isolation without regard to whether or not it is highly radioactive.

  16. Understanding Voltage Decay in Lithium-Rich Manganese-Based Layered Cathode Materials by Limiting Cutoff Voltage.

    Science.gov (United States)

    Yang, Jingsong; Xiao, Lifen; He, Wei; Fan, Jiangwei; Chen, Zhongxue; Ai, Xinping; Yang, Hanxi; Cao, Yuliang

    2016-07-27

    The effect of the cutoff voltages on the working voltage decay and cyclability of the lithium-rich manganese-based layered cathode (LRMO) was investigated by electrochemical measurements, electrochemical impedance spectroscopy, ex situ X-ray diffraction, transmission electron microscopy, and energy dispersive spectroscopy line scan technologies. It was found that both lower (2.0 V) and upper (4.8 V) cutoff voltages cause severe voltage decay with cycling due to formation of the spinel phase and migration of the transition metals inside the particles. Appropriate cutoff voltage between 2.8 and 4.4 V can effectively inhibit structural variation as the electrode demonstrates 92% capacity retention and indiscernible working voltage decay over 430 cycles. The results also show that phase transformation not only on high charge voltage but also on low discharge voltage should be addressed to obtain highly stable LRMO materials.

  17. Half-lives for α and cluster radioactivity in a simple model

    Science.gov (United States)

    Zdeb, A.; Warda, M.; Pomorski, K.

    2013-05-01

    A simple phenomenological model based on the WKB theory for the evaluation of half-lives for α and cluster radioactivity is proposed. The model contains only one adjustable parameter, the nuclear radius constant, common for both kinds of decay and three additional hindrance factors for odd-even, even-odd and odd-odd nuclei. A good agreement with the experimental data is achieved.

  18. Transport and extraction of radioactive ions stopped in superfluid helium

    NARCIS (Netherlands)

    Huang, WX; Dendooven, P; Gloos, K; Takahashi, N; Arutyunov, K; Pekola, JP; Aysto, J

    2003-01-01

    A new approach to convert a high energy beam to a low energy one, which is essential for the next generation radioactive ion beam facilities, has been proposed and tested at Jyvaskyla, Finland. An open Ra-223 alpha-decay-recoil source has been used to produce radioactive ions in superfluid helium. T

  19. Analysis of the total activation cross section of all possible reactions producing the same radioactive nuclide for the%Analysis of the total activation cross section of all possible reactions producing the same radioactive nuclide for the

    Institute of Scientific and Technical Information of China (English)

    周丰群; 宋月丽; 拓飞; 孔祥忠

    2011-01-01

    Firstly, according to the regulation of growth and decay of radioactive nuclides produced in reactions, a formula used to calculate the total activation cross section of all possible reactions producing the same radioactive nuclide for the same element is

  20. Probing flavor models with {sup 76}Ge-based experiments on neutrinoless double-β decay

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, Matteo [Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); Gran Sasso Science Institute (INFN), L' Aquila (Italy); Merle, Alexander [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Munich (Germany); Zuber, Kai [Technische Universitaet Dresden, Institute for Nuclear and Particle Physics, Dresden (Germany)

    2016-04-15

    The physics impact of a staged approach for double-β decay experiments based on {sup 76}Ge is studied. The scenario considered relies on realistic time schedules envisioned by the Gerda and the Majorana collaborations, which are jointly working towards the realization of a future larger scale {sup 76}Ge experiment. Intermediate stages of the experiments are conceived to perform quasi background-free measurements, and different data sets can be reliably combined to maximize the physics outcome. The sensitivity for such a global analysis is presented, with focus on how neutrino flavor models can be probed already with preliminary phases of the experiments. The synergy between theory and experiment yields strong benefits for both sides: the model predictions can be used to sensibly plan the experimental stages, and results from intermediate stages can be used to constrain whole groups of theoretical scenarios. This strategy clearly generates added value to the experimental efforts, while at the same time it allows to achieve valuable physics results as early as possible. (orig.)

  1. Real-time information feedback based on a sharp decay weighted function

    Science.gov (United States)

    Chen, Bokui; Dong, Chuanfei; Liu, Yike; Tong, Wei; Zhang, Wenyao; Liu, Jie; Wang, Binghong

    2012-10-01

    Information feedback strategy, serving as the critical part of intelligent traffic systems, has been treated with growing emphasis. In recent years, a variety of feedback strategies have been proposed. Despite the fact that these strategies have been proved to enhance the traffic efficiency, we find that the road capacity has not been saturated and there is still plenty of room for improvement. Based on the analytic approximations, we found the reason why corresponding angle feedback strategy is superior to weighted congestion coefficient feedback strategy. Given that the sharp decay of the weighted coefficient is the key point, we proposed an efficient feedback strategy called the exponential function feedback strategy (EFFS). We applied it to both the symmetrical two-route model with two exits and that with a single exit. The simulation results indicate that, compared with other strategies, EFFS has decided numerical advantages in average flow, a physical quantity used for depicting the road capacity. Even more importantly, EFFS stands out for its convenient application as well as its fitness for modeling the rugged roads.

  2. A feasibility study of ortho-positronium decays measurement with the J-PET scanner based on plastic scintillators

    CERN Document Server

    Kamińska, D; Czerwiński, E; Alfs, D; Bednarski, T; Białas, P; Curceanu, C; Dulski, K; Głowacz, B; Gupta-Sharma, N; Gorgol, M; Hiesmayr, B C; Jasińska, B; Korcyl, G; Kowalski, P; Krzemień, W; Krawczyk, N; Kubicz, E; Mohammed, M; Niedźwiecki, Sz; Pawlik-Niedźwiecka, M; Raczyński, L; Rudy, Z; Silarski, M; Wieczorek, A; Wiślicki, W; Zgardzińska, B; Zieliński, M; Moskal, P

    2016-01-01

    We present a study of the application of the Jagiellonian Positron Emission Tomograph (J-PET) for the registration of gamma quanta from decays of ortho-positronium (o-Ps). The J-PET is the first positron emission tomography scanner based on organic scintillators in contrast to all current PET scanners based on inorganic crystals. Monte Carlo simulations show that the J-PET as an axially symmetric and high acceptance scanner can be used as a multi-purpose detector well suited to pursue research including e.g. tests of discrete symmetries in decays of ortho-positronium in addition to the medical imaging. The gamma quanta originating from o-Ps decay interact in the plastic scintillators predominantly via the Compton effect, making the direct measurement of their energy impossible. Nevertheless, it is shown in this paper that the J-PET scanner will enable studies of the o-Ps$\\to3\\gamma$ decays with angular and energy resolution equal to $\\sigma(\\theta) \\approx 0.4^{\\circ}$ and $\\sigma(E) \\approx 4.1$ keV, respect...

  3. Design and parameter optimization of a small-scale electron-based ADS for radioactive waste transmutation

    Science.gov (United States)

    Feizi, H.; Ranjbar, A. H.

    2015-05-01

    This paper presents the design and feasibility of an electron-LINAC-based small-scale system (ADS) for nuclear waste transmutation. FLUKA simulations have been performed to evaluate the photoneutron yield in high- Z metallic targets such as silver, tungsten, lead, tantalum and uranium irradiated by electron beams of 20-200MeV. The parameters involved in the photoneutron production mechanism including electron beam energy, target material and target shape have been investigated in order to obtain maximum photoneutron production. The neutron reflectors of the ADS, in particular, beryllium, lead and beryllium oxide (BeO) with various thicknesses have been studied. The results show that a combination of an internal reflector of Pb with a thickness of 3cm and an external reflector of BeO with a thickness of 10cm improves the fluence rate. The photoneutron energy spectrum, photoneutron fluence distribution and heat deposition in the electron target have also been presented. At incident electron beam energy of 155MeV, a neutron source of ˜ 4.6 × 1010 (n/cm2/s/mA) has been achieved, which is highly applicable for using in nuclear waste transmutation. The designed ADS has the ability to transmute ˜ 1.5 × 1022 (atoms/y/mA). The obtained results are promising and could lead to the development of a small-scale ADS based on electron LINAC for radioactive waste transmutation and for numerous applications when employed as a photoneutron source.

  4. A novel approach to the systematization of α-decaying nuclei, based on shell structures

    Energy Technology Data Exchange (ETDEWEB)

    Yarman, Tolga; Azmi Altintas, Ali [Okan University, Istanbul (Turkey); Zaim, Nimet [Trakya University, Edirne (Turkey); Amon Susam, Lidya [Istanbul University, Istanbul (Turkey); Kholmetskii, Alexander [Belarus State University, Minsk (Belarus); Arik, Metin [Bogazici University, Istanbul (Turkey); Ozaydin, Fatih [Isik University, Istanbul (Turkey)

    2016-05-15

    We provide a novel systematization of α-decaying nuclei, starting with the classically adopted mechanism. The decay half-life of an α-disintegrating nucleus is framed, supposing that i) the α-particle is born inside the parent, then ii) it keeps on hitting the barrier, while it runs back and forth inside the parent, and hitting each time the barrier, and iii) it finally tunnels through the barrier. One can, knowing the decay half-life, consider the probability that the α-particle is born within the parent, before it is emitted, as a parameter. Under all circumstances, the decay appears to be governed by the shell structure of the given nucleus. Our approach well allows to incorporate (not only even-even nuclei, but) all nuclei, decaying via throwing an alpha particle. Though herein, we limit ourselves with just even-even nuclei, in the aim of comparing our results with the existing Geiger-Nuttal results. (orig.)

  5. Travel in the depth of radioactivity; Voyage au coeur de la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    This educational booklet gives a general presentation of radioactivity: origin of natural radioactivity, characteristics of atoms and isotopes, the radioactivity phenomenon, its decay and measurement units, the radiations and their use in medicine, industry, agriculture and food industry, biology etc.. (J.S.)

  6. Revisiting alpha decay-based near-light-speed particle propulsion.

    Science.gov (United States)

    Zhang, Wenwu; Liu, Zhen; Yang, Yang; Du, Shiyu

    2016-08-01

    Interplanet and interstellar travels require long-term propulsion of spacecrafts, whereas the conventional schemes of propulsion are limited by the velocity of the ejected mass. In this study, alpha particles released by nuclear decay are considered as a potential solution for long-time acceleration. The principle of near-light-speed particle propulsion (NcPP) was elucidated and the stopping and range of ions in matter (SRIM) was used to predict theoretical accelerations. The results show that NcPP by means of alpha decay is feasible for long-term spacecraft propulsion and posture adjustment in space. A practical NcPP sail can achieve a speed >150km/s and reach the brink of the solar system faster than a mass equivalent solar sail. Finally, to significantly improve the NcPP sail, the hypothesis of stimulated acceleration of nuclear decay (SAND) was proposed, which may shorten the travel time to Mars to within 20 days.

  7. A field programmable gate array-based time-resolved scaler for collinear laser spectroscopy with bunched radioactive potassium beams.

    Science.gov (United States)

    Rossi, D M; Minamisono, K; Barquest, B R; Bollen, G; Cooper, K; Davis, M; Hammerton, K; Hughes, M; Mantica, P F; Morrissey, D J; Ringle, R; Rodriguez, J A; Ryder, C A; Schwarz, S; Strum, R; Sumithrarachchi, C; Tarazona, D; Zhao, S

    2014-09-01

    A new data acquisition system including a Field Programmable Gate Array (FPGA) based time-resolved scaler was developed for laser-induced fluorescence and beam bunch coincidence measurements. The FPGA scaler was tested in a collinear laser-spectroscopy experiment on radioactive (37)K at the BEam COoler and LAser spectroscopy (BECOLA) facility at the National Superconducting Cyclotron Laboratory at Michigan State University. A 1.29 μs bunch width from the buncher and a bunch repetition rate of 2.5 Hz led to a background suppression factor of 3.1 × 10(5) in resonant photon detection measurements. The hyperfine structure of (37)K and its isotope shift relative to the stable (39)K were determined using 5 × 10(4) s(-1) (37)K ions injected into the BECOLA beam line. The obtained hyperfine coupling constants A((2)S(1/2)) = 120.3(1.4) MHz, A((2)P(1/2)) = 15.2(1.1) MHz, and A((2)P(3/2)) = 1.4(8) MHz, and the isotope shift δν(39, 37) = -264(3) MHz are consistent with the previously determined values, where available.

  8. A field programmable gate array-based time-resolved scaler for collinear laser spectroscopy with bunched radioactive potassium beams

    Science.gov (United States)

    Rossi, D. M.; Minamisono, K.; Barquest, B. R.; Bollen, G.; Cooper, K.; Davis, M.; Hammerton, K.; Hughes, M.; Mantica, P. F.; Morrissey, D. J.; Ringle, R.; Rodriguez, J. A.; Ryder, C. A.; Schwarz, S.; Strum, R.; Sumithrarachchi, C.; Tarazona, D.; Zhao, S.

    2014-09-01

    A new data acquisition system including a Field Programmable Gate Array (FPGA) based time-resolved scaler was developed for laser-induced fluorescence and beam bunch coincidence measurements. The FPGA scaler was tested in a collinear laser-spectroscopy experiment on radioactive 37K at the BEam COoler and LAser spectroscopy (BECOLA) facility at the National Superconducting Cyclotron Laboratory at Michigan State University. A 1.29 μs bunch width from the buncher and a bunch repetition rate of 2.5 Hz led to a background suppression factor of 3.1 × 105 in resonant photon detection measurements. The hyperfine structure of 37K and its isotope shift relative to the stable 39K were determined using 5 × 104 s-1 37K ions injected into the BECOLA beam line. The obtained hyperfine coupling constants A(2S1/2) = 120.3(1.4) MHz, A(2P1/2) = 15.2(1.1) MHz, and A(2P3/2) = 1.4(8) MHz, and the isotope shift δν39, 37 = -264(3) MHz are consistent with the previously determined values, where available.

  9. Environmental radioactivity survey in Suwon

    Energy Technology Data Exchange (ETDEWEB)

    Park, Won Keun; Park, Jong Mi [Kyunghee Univ., Suwon (Korea, Republic of)

    2003-12-15

    The project is carried out to monitor the change of environmental radioactivity in Suwon, and to provide a systematic data for radiation monitoring and counter measurement at a radiological emergency situation. Also the survey of natural environmental radioactivities in the samples was conducted to make the reliable data base for evaluation of internal exposure and environmental contamination of radiation. This report contains the data of gamma exposure rates and radioactivities of airborne dust, fallout, precipitation and tap water which were analyzed periodically by Suwon regional monitoring station m 2003. Also it contains the data of natural radioactivity levels of environmental samples such as soil, drinking water, indicator plant(mugwort, pine-needle), agricultural and forest products, and processed food(tea)

  10. Radioactive airborne effluents and the environmental impact assessment of CAP1400 nuclear power plant under normal operation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qiong; Guo, RuiPing; Zhang, ChunMing; Chen, XiaoQiu; Wang, Bo, E-mail: wangbo@chinansc.cn

    2014-12-15

    Highlights: • Typical radionuclides dispersion from CAP1400 under normal operation was simulated. • Modified Gaussian model considered radioactive decay, dry and wet deposition and so on. • The radioactive impact pathways on the public through atmosphere were compared. • The maximum individual effective dose was lower than the public irradiation limit. - Abstract: China Advanced Passive nuclear power plant with installed capacity reaching to 1400 MW (CAP1400) is independently designed as the China's state-of-the-art third generation nuclear power brand based on AP1000 technology digestion and absorption. The concentration of typical radionuclides dispersed from CAP1400 under normal operation was calculated with modified Gaussian model, considering mixed layer height, dry deposition, wet deposition, radioactive decay and so on. The atmospheric dispersion factors, ground deposition rate, individual dose and public dose were also investigated to estimate the radioactive effects of CAP1400 under normal operation on surrounding environment and human beings. The radioactive impact pathways on the public through atmosphere, such as immersion irradiation in the smoke plume, internal irradiation from ingestion and inhalation and external irradiation from surface deposition were briefly introduced with focus on the comparison of the maximum individual effective dose to different group from atmospheric dispersion. All computation results show that the maximum individual irradiation dose happened to children with total effective irradiation dose of 4.52E−03 mSv/y, which was lower than the public irradiation limit of 0.25 mSv/y.

  11. Trilateration-based reconstruction of ortho-positronium decays into three photons with the J-PET detector

    CERN Document Server

    Gajos, A; Czerwiński, E; Alfs, D; Bednarski, T; Białas, P; Głowacz, B; Gorgol, M; Jasińska, B; Kapłon, Ł; Korcyl, G; Kowalski, P; Kozik, T; Krzemień, W; Kubicz, E; Mohammed, M; Niedźwiecki, Sz; Pałka, M; Pawlik-Niedźwiecka, M; Raczyński, L; Rudy, Z; Rundel, O; Sharma, N G; Silarski, M; Słomski, A; Strzelecki, A; Wieczorek, A; Wiślicki, W; Zgardzińska, B; Zieliński, M; Moskal, P

    2016-01-01

    This work reports on a new reconstruction algorithm allowing to reconstruct the decays of ortho-positronium atoms into three photons using the places and times of photons recorded in the detector. The method is based on trilateration and allows for a simultaneous reconstruction of both location and time of the decay. Results of resolution tests of the new reconstruction in the J-PET detector based on Monte Carlo simulations are presented, which yield a spatial resolution at the level of 2 cm (FWHM) for X and Y and at the level of 1 cm (FWHM) for Z available with the present resolution of J-PET after application of a kinematic fit. Prospects of employment of this method for studying angular correlations of photons in decays of polarized ortho-positronia for the needs of tests of CP and CPT discrete symmetries are also discussed. The new reconstruction method allows for discrimination of background from random three-photon coincidences as well as for application of a novel method for determination of the linear...

  12. Trilateration-based reconstruction of ortho-positronium decays into three photons with the J-PET detector

    Energy Technology Data Exchange (ETDEWEB)

    Gajos, A.; Kamińska, D. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Cracow (Poland); Czerwiński, E., E-mail: eryk.czerwinski@uj.edu.pl [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Cracow (Poland); Alfs, D.; Bednarski, T.; Białas, P.; Głowacz, B. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Cracow (Poland); Gorgol, M.; Jasińska, B. [Department of Nuclear Methods, Institute of Physics, Maria Curie-Skłodowska University, 20-031 Lublin (Poland); Kapłon, Ł. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Cracow (Poland); Institute of Metallurgy and Materials Science of Polish Academy of Sciences, Cracow (Poland); Korcyl, G. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Cracow (Poland); Kowalski, P. [Świerk Computing Centre, National Centre for Nuclear Research, 05-400 Otwock-Świerk (Poland); Kozik, T. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Cracow (Poland); Krzemień, W. [High Energy Department, National Centre for Nuclear Research, 05-400 Otwock-Świerk (Poland); Kubicz, E.; Mohammed, M.; Niedźwiecki, Sz.; Pałka, M.; Pawlik-Niedźwiecka, M. [Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Cracow (Poland); and others

    2016-05-21

    This work reports on a new reconstruction algorithm allowing us to reconstruct the decays of ortho-positronium atoms into three photons using the places and times of photons recorded in the detector. The method is based on trilateration and allows for a simultaneous reconstruction of both location and time of the decay. Results of resolution tests of the new reconstruction in the J-PET detector based on Monte Carlo simulations are presented, which yield a spatial resolution at the level of 2 cm (FWHM) for X and Y and at the level of 1 cm (FWHM) for Z available with the present resolution of J-PET after application of a kinematic fit. Prospects of employment of this method for studying angular correlations of photons in decays of polarized ortho-positronia for the needs of tests of CP and CPT discrete symmetries are also discussed. The new reconstruction method allows for discrimination of background from random three-photon coincidences as well as for application of a novel method for determination of the linear polarization of ortho-positronium atoms, which is also introduced in this work.

  13. Optimization of the Transport Shield for Neutrinoless Double Beta-decay Enriched Germanium

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.; Reid, Douglas J.; Fast, James E.

    2012-04-15

    This document presents results of an investigation of the material and geometry choice for the transport shield of germanium, the active detector material used in 76Ge neutrinoless double beta decay searches. The objective of this work is to select the optimal material and geometry to minimize cosmogenic production of radioactive isotopes in the germanium material. The design of such a shield is based on the calculation of the cosmogenic production rate of isotopes that are known to cause interfering backgrounds in 76Ge neutrinoless double beta decay searches.

  14. Application of Origen2.1 in the decay photon spectrum calculation of spallation products

    OpenAIRE

    Hong, Shuang; Yang, Yong-Wei; Xu, Hu-Shan; Meng, Hai-Yan; Zhang, Lu; Liu, Zhao-Qing; Gao, Yu-Cui; Chen, Kang

    2016-01-01

    Origen2.1 is a widely used computer code for calculating the burnup, decay, and processing of radioactive materials. However, the nuclide library of Origen2.1 is used for existing reactors like pressurized water reactor, to calculate the photon spectrum released by the decay of spallation products, we have made specific libraries for the ADS tungsten spallation target, based on the results given by a Monte Carlo code: FLUKA. All the data used to make the Origen2.1 libraries is obtained from N...

  15. Systematics of half-lives for proton radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, E.L.; Rodrigues, M.M.N.; Duarte, S.B.; Tavares, O.A.P. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]. E-mails: emil@cbpf.br; sbd@cbpf.br; oaptavares@cbpf.br

    2007-07-01

    Half-life measurements for both ground-state and isomeric transitions in proton radioactivity are systematized by using a semiempirical, one-parameter model based on tunneling through a potential barrier, where the centrifugal and overlapping effects are taken into account within the spherical nucleus approximation. This approach, which has been successfully applied to alpha decay cases covering {approx} 30 orders of magnitude in half-life, has shown, in addition, very adequate at fitting all existing data on partial half-life, T{sub 1/2p}, of proton emission from nuclei. Nearly 70 measured half-life values have been analysed, and the data could be described by two straight lines relating the pure Coulomb contribution to half life with the quantity Z{sub d}({mu}{sub 0}/Q{sub p}){sub 1/2} (Z{sub d} is the atomic number of the daughter nucleus, {mu}{sub 0} is the reduced mass, and Q{sub p} is the total nuclear energy available for decay). These straight lines are shown to correspond to different degrees of deformation, namely, very prolate ({delta}> approx. 0.1), and other shaped (delta < approx. 0.1) parent nuclei. The goodness in reproducing the data attained in the present systematics allows for half-life predictions for a few possible cases of proton radioactivity not yet experimentally accessed. (author)

  16. /sup 5/He radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Poenaru, D.N.; Ivascu, M. (Institute for Physics and Nuclear Engineering, Bucharest (Romania))

    1984-07-01

    The disintegration of a metastable nuclear state by emission of a light particle can be considered to be a very asymmetric fission process. An approximation of the potential barrier in the overlapping region of the two fragments leads to an analytic relationship for the life-time, allowing us to handle a large number of cases to search for new kinds of radioactivities. In this way, it is predicted that some nuclei with Z=83-92, N=127-137 and 97-105, 145-157 are able to decay spontaneously by emission of /sup 5/He particles. A tentative optimistic estimation leads to the result that only 15 radionuclides should have partial life-times in the range 10/sup 14/-10/sup 38/ years; all others, except some superheavies, are longer lived. The best candidate is /sup 213/Po for which the daughter is a double magic nucleus. Smaller life-times, with a better chance to be experimentally confirmed have some ..beta..-delayed /sup 5/He emitters, as for example /sup 155/Yb, /sup 175/Pt, /sup 209 -217/Ra, /sup 9 -11/Be, /sup 13 -14/B, /sup 13 -17/C and /sup 19 -21/O.

  17. Future double beta decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Piquemal, F. [Laboratoire Souterrain de Modane, Modane (France); Centre d' Etudes Nucleaire, Bordeaux-Gradignan (France)

    2013-02-15

    The search of neutrinoless double beta decay is very challenging because of the expected half-life of the process and the backgrounds from the natural radioactivity. Many projects exist to try to reach a sensitivity of ∼50 meV on the effective neutrino mass corresponding to a mass of isotopes of ∼100 kg. In this article some of the futur projects are presented.

  18. Italian Antarctic Research Program: environmental radioactivity survey around the Italian base (1987-1991) Terra Nova Bay - Ross Sea region

    Energy Technology Data Exchange (ETDEWEB)

    Tubertini, O.; Bettoli, M.G.; Cantelli, L. [Bologna Univ. (Italy)] [and others

    1995-12-31

    Investigations have been carried out by the Italian Antartic Research Program to determine the natural and artificial radioactivity levels of both the marine and terrestrial environments. Also, natural and anthropogenic fluxes of aerosol particles onto the Antartic surface have been examined. (Author).

  19. Spectrum correction algorithm for detectors in airborne radioactivity monitoring equipment NH-UAV based on a ratio processing method

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Ye [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Tang, Xiao-Bin, E-mail: tangxiaobin@nuaa.edu.cn [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Jiangsu Key Laboratory of Nuclear Energy Equipment Materials Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Wang, Peng; Meng, Jia; Huang, Xi; Wen, Liang-Sheng [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Chen, Da [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Jiangsu Key Laboratory of Nuclear Energy Equipment Materials Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

    2015-10-11

    The unmanned aerial vehicle (UAV) radiation monitoring method plays an important role in nuclear accidents emergency. In this research, a spectrum correction algorithm about the UAV airborne radioactivity monitoring equipment NH-UAV was studied to measure the radioactive nuclides within a small area in real time and in a fixed place. The simulation spectra of the high-purity germanium (HPGe) detector and the lanthanum bromide (LaBr{sub 3}) detector in the equipment were obtained using the Monte Carlo technique. Spectrum correction coefficients were calculated after performing ratio processing techniques about the net peak areas between the double detectors on the detection spectrum of the LaBr{sub 3} detector according to the accuracy of the detection spectrum of the HPGe detector. The relationship between the spectrum correction coefficient and the size of the source term was also investigated. A good linear relation exists between the spectrum correction coefficient and the corresponding energy (R{sup 2}=0.9765). The maximum relative deviation from the real condition reduced from 1.65 to 0.035. The spectrum correction method was verified as feasible. - Highlights: • An airborne radioactivity monitoring equipment NH-UAV was developed to measure radionuclide after a nuclear accident. • A spectrum correction algorithm was proposed to obtain precise information on the detected radioactivity within a small area. • The spectrum correction method was verified as feasible. • The corresponding spectrum correction coefficients increase first and then stay constant.

  20. Size measurement of radioactive aerosol particles in intense radiation fields using wire screens and imaging plates

    Energy Technology Data Exchange (ETDEWEB)

    Oki, Yuichi; Tanaka, Toru; Takamiya, Koichi; Ishi, Yoshihiro; UesugI, Tomonori; Kuriyama, Yasutoshi; Sakamoto, Masaaki; Ohtsuki, Tsutomu [Kyoto University Research Reactor Institute, Osaka (Japan); Nitta, Shinnosuke [Graduate School of Engineering, Kyoto University, Kyoto (Japan); Osada, Naoyuki [Advanced Science Research Center, Okayama University, Okayama (Japan)

    2016-09-15

    Very fine radiation-induced aerosol particles are produced in intense radiation fields, such as high-intensity accelerator rooms and containment vessels such as those in the Fukushima Daiichi nuclear power plant (FDNPP). Size measurement of the aerosol particles is very important for understanding the behavior of radioactive aerosols released in the FDNPP accident and radiation safety in high-energy accelerators. A combined technique using wire screens and imaging plates was developed for size measurement of fine radioactive aerosol particles smaller than 100 nm in diameter. This technique was applied to the radiation field of a proton accelerator room, in which radioactive atoms produced in air during machine operation are incorporated into radiation-induced aerosol particles. The size of 11C-bearing aerosol particles was analyzed using the wire screen technique in distinction from other positron emitters in combination with a radioactive decay analysis. The size distribution for 11C-bearing aerosol particles was found to be ca. 70 μm in geometric mean diameter. The size was similar to that for 7Be-bearing particles obtained by a Ge detector measurement, and was slightly larger than the number-based size distribution measured with a scanning mobility particle sizer. The particle size measuring method using wire screens and imaging plates was successfully applied to the fine aerosol particles produced in an intense radiation field of a proton accelerator. This technique is applicable to size measurement of radioactive aerosol particles produced in the intense radiation fields of radiation facilities.

  1. Threedimensional dynamics of nuclear decay modes

    Science.gov (United States)

    Mirea, M.; Poenaru, D. N.; Greiner, W.

    1994-03-01

    We study nondissipative fission dynamics in a wide range of mass asymmetry, covering three groups of nuclear decay modes: cluster radioactivities; alpha-decay and cold fission. The WKB action integral is calculated by using the Werner-Wheeler inertia tensor and the deformation energy within Yukawa-plus-exponential model extended to binary systems with different charge densities. The optimum dynamical trajectory in a threedimensional deformation space (elongation, necking-in and mass-asymmetry) is determined by solving a nonlinear system of differential equations. This new method is illustrated for three decay modes of234U: α-decay, Mg-radioactivity and cold fission with100Zr as a light fragment.

  2. HALF-LIVES OF LONG-LIVED A-DECAY, B-DECAY, BB-DECAY AND SPONTANEOUS FISSION NUCLIDES.

    Energy Technology Data Exchange (ETDEWEB)

    HOLDEN,N.E.

    2001-06-29

    In his review of radionuclides for dating purposes, Roth noted that there were a large number of nuclides, normally considered ''stable'' but which are radioactive with a very long half-life. Roth suggested that I review the data on the half-life values of these long-lived nuclides for a discussion session at the next meeting. These half-life values for long-lived nuclides include those due to various decay modes, {alpha}-decay, {beta}-decay, electron capture decay, {beta}{beta}-decay and spontaneous fission decay. This report is preliminary but will provide a quick overview of the extensive table of data on the recommendations from that review.

  3. Radioactivity in consumer products

    Energy Technology Data Exchange (ETDEWEB)

    Moghissi, A.A.; Paras, P.; Carter, M.W.; Barker, R.F. (eds.)

    1978-08-01

    Papers presented at the conference dealt with regulations and standards; general and biological risks; radioluminous materials; mining, agricultural, and construction materials containing radioactivity; and various products containing radioactive sources.

  4. Concentration Limits in the Cement Based Swiss Repository for Long-lived, Intermediate-level Radioactive Wastes (LMA)

    Energy Technology Data Exchange (ETDEWEB)

    Berner, Urs

    1999-12-01

    The Swiss repository concept for long-lived, intermediate-level radioactive wastes (LMA), in Swiss terminology) foresees cylindrical concrete silos surrounded by a ring of granulated bentonite to deposit the waste. As one of the possible options and similar to the repository for high level wastes, the silos will be located in a deep crystalline host rock. Solidified with concrete in steel drums, the waste is stacked into a silo and the silo is then backfilled with a porous mortar. To characterize the release of radionuclides from the repository, the safety assessment considers first the dissolution into the pore water of the concrete, and then diffusion through the outer bentonite ring into the deep crystalline groundwater. For 19 safety relevant radionuclides (isotopes of U, Th, Pa, Np, Pu, Am, Ni, Zr, Mo, Nb, Se, Sr, Ra, Tc, Sn, I, C, Cs, Cl) the report recommends maximum elemental concentrations to be expected in the cement pore water of the particularly considered repository. These limits will form the parameter base for subsequent release model chains. Concentration limits in a geochemical environment are usually obtained from thermodynamic equilibrium calculations performed with geochemical speciation codes. However, earlier studies revealed that this procedure does not always lead to reliable results. Main reasons for this are the complexity of the systems considered, as well as the lacking completeness of, and the uncertainty associated with the thermodynamic data. To improve the recommended maximum concentrations for a distinct repository design, this work includes additional design- and system-dependent criteria. The following processes, inventories and properties are considered in particular: a) recent experimental investigations, particularly from cement systems, b) thermodynamic model calculations when reliable data are available, c) total inventories of radionuclides, d) sorption- and co-precipitation processes, e) dilution with stable isotopes, f

  5. A Test of QCD based on 4 jet events from $Z^{0}$ decays

    CERN Document Server

    McBride, P L

    1991-01-01

    Th e measure d angula r correlation s betwee n jet s i n 4-je t event s fro m Z ° boso n decay s ar e wel l reproduce d b y QCD . A n alternativ e abelia n mode l fail s t o describ e th e data . Th e mai n differenc e i s du e t o th e larg e rat e o f qqqq fina l state s i n th e abelia n model .

  6. A kinematic model to estimate effective dose of radioactive substances in a human body

    Science.gov (United States)

    Sasaki, S.; Yamada, T.

    2013-05-01

    The great earthquake occurred in the north-east area in Japan in March 11, 2011. Facility system to control Fukushima Daiichi nuclear power station was completely destroyed by the following giant tsunami. From the damaged reactor containment vessels, an amount of radioactive substances had leaked and diffused in the vicinity of this station. Radiological internal exposure became a serious social issue both in Japan and all over the world. The present study provides an easily understandable, kinematic-based model to estimate the effective dose of radioactive substances in a human body by simplifying the complicated mechanism of metabolism. International Commission on Radiological Protection (ICRP) has developed a sophisticated model, which is well-known as a standard method to calculate the effective dose for radiological protection. However, owing to that ICRP method is fine, it is rather difficult for non-professional people of radiology to gasp the whole images of the movement and the influences of radioactive substances in a human body. Therefore, in the present paper we propose a newly-derived and easily-understandable model to estimate the effective dose. The present method is very similar with the traditional and conventional tank model in hydrology. Ingestion flux of radioactive substances corresponds to rain intensity and the storage of radioactive substances to the water storage in a basin in runoff analysis. The key of the present method is to estimate the energy radiated in the radioactive nuclear disintegration of an atom by using classical theory of β decay and special relativity for various kinds of radioactive atoms. The parameters used in this model are only physical half-time and biological half-time, and there are no operational parameters or coefficients to adjust our theoretical runoff to ICRP. Figure shows the time-varying effective dose with ingestion duration, and we can confirm the validity of our model. The time-varying effective dose with

  7. Convivial Decay

    DEFF Research Database (Denmark)

    Cohn, Marisa

    2016-01-01

    in the life of infrastructure we can observe common issues associated with aging infrastructures – hardware’s material decay, programming languages and software tools reaching end of support, obsolete managerial methodologies, etc. Such a case of infrastructural decay reveals how work of infrastructure...... maintenance may reach the limits of repair and shift from repair-as-sustaining into a mode of repair- into-decay, actively working towards the end-of-life. What this reveals is that, rather than infrastructural decay being a natural by-product of time’s passing, there is active work that goes into producing......This paper discusses the empirical case of an aging and obsolescent infrastructure supporting a space science mission that is currently approaching a known end. Such a case contributes to our understanding of the degrading path at the end-of-life of an infrastructure. During this later stage...

  8. Proton Decay

    OpenAIRE

    Hikosaka, Koki

    2002-01-01

    We discuss the status of supersymmetric grand unified theories [SUSY GUTs] with regards to the observation of proton decay. In this talk we focus on SUSY GUTs in 4 dimensions. We outline the major theoretical uncertainties present in the calculation of the proton lifetime and then present our best estimate of an absolute upper bound on the predicted proton lifetime. Towards the end, we consider some new results in higher dimensional GUTs and the ramifications for proton decay.

  9. A Technical Review of Penning Trap based Investigations in Neutron Decay

    CERN Document Server

    Byrne, J

    2014-01-01

    This review is concerned with a detailed analysis of some of the technical problems which arise in the application of the Penning trap method to the experimental study of neutron $\\beta $ -decay,a technique which was first successfully tested on the low-flux swimming-pool reactor LIDO (capture flux =3$\\cdot 10^6$cm$^(-2)$s$^(-1)$) at AERE Harwell in the 1970's. It does not discuss the scientific merits or demerits of these studies. Of particular importance are the trapping and release of neutron decay protons, and the influence of magnetic mirror effects and radial drifting on the trapped particles. Since these have energies < 1 keV they must be accelerated to energies of order 20-30 keV following release, at which point they are recorded in a silicon surface barrier detector. However serious difficulties were encountered in the post-release acceleration process with vacuum breakdown in the presence of crossed electric and magnetic fields.

  10. Identification of Metals (Heavy and Radioactive in Drinking Water by an Indirect Analysis Method Based on Scale Tests

    Directory of Open Access Journals (Sweden)

    Sasa Jovanic

    2008-03-01

    Full Text Available The analysis of water quality, regarding the content of metals, especially heavy and radioactive ones, has been carried out in an indirect way, by testing scale formed in a hot-water heater, using water from the water-supply network of the city of Belgrade – the district of New Belgrade. The determination of the composition and the structure of the scale has resulted in its complete identification, and its crystallochemical formula has been defined. It has unequivocally been established that the obtained results are within the tolerance boundary with the results acquired by a conventional analysis of water, when it is a matter of very low concentrations. The presence of radioactive elements of uranium and strontium in a scale sample has been found and the way of their penetrating its composition and structure has been explained. Applying the fractional extraction method, uranium has been established to be of an anthropogenic origin.

  11. Semileptonic Decays

    Energy Technology Data Exchange (ETDEWEB)

    Luth, Vera G.; /SLAC

    2012-10-02

    The following is an overview of the measurements of the CKM matrix elements |V{sub cb}| and |V{sub ub}| that are based on detailed studies of semileptonic B decays by the BABAR and Belle Collaborations and major advances in QCD calculations. In addition, a new and improved measurement of the ratios R(D{sup (*)}) = {Beta}({bar B} {yields} D{sup (*)}{tau}{sup -}{bar {nu}}{sub {tau}})/{Beta}({bar B} {yields} D{sup (*)}{ell}{sup -}{bar {nu}}{sub {ell}}) is presented. Here D{sup (*)} refers to a D or a D* meson and {ell} is either e or {mu}. The results, R(D) = 0.440 {+-} 0.058 {+-} 0.042 and R(D*) = 0.332 {+-} 0.024 {+-} 0.018, exceed the Standard Model expectations by 2.0{sigma} and 2.7{sigma}, respectively. Taken together, they disagree with these expectations at the 3.4{sigma} level. The excess of events cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

  12. Nuclear astrophysics with radioactive ions at FAIR

    OpenAIRE

    2016-01-01

    The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular ...

  13. Radioactive isotopes in solid-state physics

    CERN Document Server

    Deicher, M

    2002-01-01

    Radioactive atoms have been used in solid-state physics and in material science for many decades. Besides their classical application as tracer for diffusion studies, nuclear techniques such as M\\"ossbauer spectroscopy, perturbed angular correlation, $\\beta$-NMR, and emission channelling have used nuclear properties (via hyperfine interactions or emitted particles) to gain microscopical information on the structural and dynamical properties of solids. During the last decade, the availability of many different radioactive isotopes as a clean ion beam at ISOL facilities such as ISOLDE at CERN has triggered a new era involving methods sensitive for the optical and electronic properties of solids, especially in the field of semiconductor physics. Extremely sensitive spectroscopic techniques like deep-level transient spectroscopy (DLTS), photoluminescence (PL), and Hall effect have gained a new quality by using radioactive isotopes. Because of their decay the chemical origin of an observed electronic and optical b...

  14. Thermodynamic stability of radioactivity standard solutions

    Energy Technology Data Exchange (ETDEWEB)

    Iroulard, M.G

    2007-04-15

    The basic requirement when preparing radioactivity standard solutions is to guarantee the concentration of a radionuclide or a radioelement, expressed in the form of activity concentration (Ac = A/m (Bq/g), with A: activity and m: mass of solution). Knowledge of the law of radioactive decay and the half-life of a radionuclide or radioelement makes it possible to determine the activity concentration at any time, and this must be confirmed subsequently by measurement. Furthermore, when radioactivity standard solutions are prepared, it is necessary to establish optimal conditions of thermodynamic stability of the standard solutions. Radioactivity standard solutions are prepared by metrology laboratories from original solutions obtained from a range of suppliers. These radioactivity standard solutions must enable preparation of liquid and/or solid radioactivity standard sources of which measurement by different methods can determine, at a given instant, the activity concentration of the radionuclide or radioelement present in the solution. There are a number of constraints associated with the preparation of such sources. Here only those that relate to the physical and chemical properties of the standard solution are considered, and therefore need to be taken into account when preparing a radioactivity standard solution. These issues are considered in this document in accordance with the following plan: - A first part devoted to the chemical properties of the solutions: - the solubilization media: ultra-pure water and acid media, - the carriers: concentration, oxidation state of the radioactive element and the carrier element. - A second part describing the methodology of the preparation, packaging and storage of standard solutions: - glass ampoules: the structure of glasses, the mechanisms of their dissolution, the sorption phenomenon at the solid-solution interface, - quartz ampoules, - cleaning and packaging: cleaning solutions, internal surface coatings and

  15. MONITORING OF RADIOACTIVITY AT DNURT CAMPUS

    Directory of Open Access Journals (Sweden)

    L. F. Dolina

    2016-06-01

    Full Text Available Purpose. The research paper aims to determine radioactive contamination on the territory of campus of Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan (DNURT. Methodology. The dosimeters measured the radioactive contamination in different places (points of DNURT campus, focusing on public places. The centres of measurements became dormitories, monuments, stops, main entrances of the new and the old buildings, classrooms, basements, a swimming pool, boiler room and others. Findings. The conducted radiation monitoring for the first time in the history of the University discovered the source of radioactive contamination on DNURT territory and campus. The highest radiation background is observed on three points, namely: the pedestal of the monument, the monument to students-soldiers, the main entrance of the new building (columns. This can be explained by granite materials, which the pedestals and the stairs are made of. Originality. The largest contribution to the total value of annual effective dose of human exposure is made by ionizing radiation sources (IRS of building materials (65 - 70%. The radioactivity level of building materials is determined by the content of natural radionuclides that are included in uranium-radium and thorium decay series (18 and 12 radionuclides as well as potassium-40. Radioactivity of building materials is evaluated by the content of dominant radionuclides radium-226, thorium-232 and potassium-40. Their dominant role is explained by the fact that these long-lived high-energy - emitters are the products of decay of radium-226 in uranium series of and radium-224 in thorium series, exposing radioactive gases (radon-222 and radon-220. Radioactive gases are accumulated in the basements of educational buildings; their decay is accompanied by 100% alpha radiation, which is the most dangerous. Practical value. It is necessary to set radioactivity signs near the objects with high

  16. 10 CFR 72.104 - Criteria for radioactive materials in effluents and direct radiation from an ISFSI or MRS.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Criteria for radioactive materials in effluents and direct... radioactive materials, radon and its decay products excepted, to the general environment, (2) Direct radiation... objectives for radioactive materials in effluents and direct radiation levels associated with ISFSI or...

  17. Generalized unscented Kalman filtering based radial basis function neural network for the prediction of ground radioactivity time series with missing data

    Institute of Scientific and Technical Information of China (English)

    Wu Xue-Dong; Wang Yao-Nan; Liu Wei-Ting; Zhu Zhi-Yu

    2011-01-01

    On the assumption that random interruptions in the observation process are modeled by a sequence of independent Bernoulli random variables, we firstly generalize two kinds of nonlinear filtering methods with random interruption failures in the observation based on the extended Kalman filtering (EKF) and the unscented Kalman filtering (UKF),which were shortened as GEKF and GUKF in this paper, respectively. Then the nonlinear filtering model is established by using the radial basis function neural network (RBFNN) prototypes and the network weights as state equation and the output of RBFNN to present the observation equation. Finally, we take the filtering problem under missing observed data as a special case of nonlinear filtering with random intermittent failures by setting each missing data to be zero without needing to pre-estimate the missing data, and use the GEKF-based RBFNN and the GUKF-based RBFNN to predict the ground radioactivity time series with missing data. Experimental results demonstrate that the prediction results of GUKF-based RBFNN accord well with the real ground radioactivity time series while the prediction results of GEKF-based RBFNN are divergent.

  18. 基于RFID/GPRS的放射源监控系统%Radioactive Source Monitoring System Based on RFID and GPRS

    Institute of Scientific and Technical Information of China (English)

    何海洋; 周洪亮; 张宏建; 张胜; 周俊儒; 翁国杰

    2011-01-01

    Nuclear radiation produced by radioactive source is harmful to the health of human body, and the lost and theft of radioactive source will cause environmental pollution and social panic. In order to solve the abnormal leaks, accidental loss, theft and other problems of the radioactive source, a radioactive source monitoring system based on RFID, GPS, GPRS and GSM technology is put forward. Radiation dose detector and GPS wireless location module are used to obtain the information of radiation dose and location respectively, RFID reader reads the status of a tag fixed on the bottom of the radioactive source. All information is transmitted to the remote monitoring center via GPRS wireless transmission. There will be an audible and visual alarm when radiation dose is out of limits or the state of radioactive source is abnormal, and the monitoring center will send a-larming text messages to the managers through GSM Modem at the same time. Thus, the functions of monitoring and alarming are achieved. The system has already been put into operation and is being kept in functional order. It can provide stable statistics as well as accurate alarm, improving the supervision of radioactive source effectively.%放射源产生的核辐射对人体的健康具有危害性,而放射源的丢失与被盗更会造成环境污染,引起社会恐慌.为了解决放射源的异常泄漏和意外丢失、被盗等问题,研制了基于RFID、GPS、GPRS和GSM等技术的放射源监控系统.辐射剂量检测仪和GPS无线定位模块分别实时获取放射源辐射剂量值与位置信息,RFID阅读器读取安装在放射源底部的电子标签状态信息.放射源辐射剂量值、位置与标签状态信息通过GPRS无线传输方式发送到远程监控中心.当辐射剂量超标或者放射源状态异常时,现场进行声光报警,同时监控中心通过GSM Modem向管理人员发送短信报警,从而实现对放射源的监控与报警.该系统投入运行效果良

  19. Nucleon Decay and Neutrino Properties in a Mass Model based on an SO(10) Grand Unified Theory

    CERN Document Server

    Merten, C

    2000-01-01

    In this work a mass model based on a SO(10) GUT with a global U(1) familysymmetry is discussed which leads to an asymmetric Nearest NeighbourInteraction structure for the fermionic mass matrices. As a result of theanalysis one gets three solutions of the model which include several largeleft- and right-handed fermion mixings. Those mixings are not observable in theSM where only the CKM quark mixing matrix can be measured, but they havetestable effects on the branching ratios of nucleon decays in theories beyondthe SM. One finds that decay channels with positrons in the final state aresuppressed while channels with antimuons and antineutrinos are enhancedcompared to models with small mixings. The total nucleon lifetimes obtainedshould be observable by future experiments. The SO(10) model also predicts themasses and mixings of the light neutrinos. They are in the right range toexplain the anomalies of solar and atmospheric neutrinos by means ofoscillations, preferring the small angle MSW solution for the solar ...

  20. B decays

    CERN Document Server

    Stone, Sheldon

    1994-01-01

    This book reviews the study of b quarks and also looks at the implications of future studies. The most important observations thus far - including measurement of the ""B"" lifetime and observations of b -> u transitions - as well as the more mundane results of hadronic and semileptonic transitions are described in detail by experimentalists who have been closely involved with the measurements. Theoretical progress in understanding b quark decays, including the mechanisms of hadronic and semileptonic decays, are described. Synthesizing the experimental and theoretical information, the authors d

  1. B decays

    CERN Document Server

    Stone, Sheldon

    1992-01-01

    The study of b quarks has now reached a stage where it is useful to review what has been learned so far and also to look at the implications of future studies. The most important observations thus far - measurement of the "B" lifetime, B 0 - B 0 mixing, and the observation of b? u transitions, as well as more mundane results on hadronic and semileptonic transitions - are described in detail by experimentalists who have been closely involved with the measurements. Theoretical progress in understanding b quark decays, including the mechanisms of hadronic and semileptonic decays, are described. S

  2. ANITA-2000 activation code package - updating of the decay data libraries and validation on the experimental data of the 14 MeV Frascati Neutron Generator

    Directory of Open Access Journals (Sweden)

    Frisoni Manuela

    2016-01-01

    Full Text Available ANITA-2000 is a code package for the activation characterization of materials exposed to neutron irradiation released by ENEA to OECD-NEADB and ORNL-RSICC. The main component of the package is the activation code ANITA-4M that computes the radioactive inventory of a material exposed to neutron irradiation. The code requires the decay data library (file fl1 containing the quantities describing the decay properties of the unstable nuclides and the library (file fl2 containing the gamma ray spectra emitted by the radioactive nuclei. The fl1 and fl2 files of the ANITA-2000 code package, originally based on the evaluated nuclear data library FENDL/D-2.0, were recently updated on the basis of the JEFF-3.1.1 Radioactive Decay Data Library. This paper presents the results of the validation of the new fl1 decay data library through the comparison of the ANITA-4M calculated values with the measured electron and photon decay heats and activities of fusion material samples irradiated at the 14 MeV Frascati Neutron Generator (FNG of the NEA-Frascati Research Centre. Twelve material samples were considered, namely: Mo, Cu, Hf, Mg, Ni, Cd, Sn, Re, Ti, W, Ag and Al. The ratios between calculated and experimental values (C/E are shown and discussed in this paper.

  3. A simple decay-spectroscopy station at CRIS-ISOLDE

    Science.gov (United States)

    Lynch, K. M.; Cocolios, T. E.; Althubiti, N.; Farooq-Smith, G. J.; Gins, W.; Smith, A. J.

    2017-02-01

    A new decay-spectroscopy station (DSS2.0) has been designed by the CRIS collaboration for use at the radioactive ion beam facility, ISOLDE. With the design optimised for both charged-particle and γ-ray detection, the DDS2.0 allows high-efficiency decay spectroscopy to be performed. The DSS2.0 complements the existing decay-spectroscopy system at the CRIS experiment, and together provide the ability to perform laser-assisted nuclear decay spectroscopy on both ground state and long-lived isomeric species. This paper describes the new decay-spectroscopy station and presents the characterisation studies that have recently been performed.

  4. Comparisons between radioactive and non-radioactive gas lantern mantles.

    Science.gov (United States)

    Furuta, E; Yoshizawa, Y; Aburai, T

    2000-12-01

    Gas lantern mantles containing radioactive thorium have been used for more than 100 years. Although thorium was once believed to be indispensable for giving a bright light, non-radioactive mantles are now available. From the radioactivities of the daughter nuclides, we estimated the levels of radioactivity of 232Th and 228Th in 11 mantles. The mantles contained various levels of radioactivity from background levels to 1410 +/- 140 Bq. Our finding that radioactive and non-radioactive mantles are equally bright suggests that there is no advantage in using radioactive mantles. A remaining problem is that gas lantern mantles are sold without any information about radioactivity.

  5. Radioactive air sampling methods

    CERN Document Server

    Maiello, Mark L

    2010-01-01

    Although the field of radioactive air sampling has matured and evolved over decades, it has lacked a single resource that assimilates technical and background information on its many facets. Edited by experts and with contributions from top practitioners and researchers, Radioactive Air Sampling Methods provides authoritative guidance on measuring airborne radioactivity from industrial, research, and nuclear power operations, as well as naturally occuring radioactivity in the environment. Designed for industrial hygienists, air quality experts, and heath physicists, the book delves into the applied research advancing and transforming practice with improvements to measurement equipment, human dose modeling of inhaled radioactivity, and radiation safety regulations. To present a wide picture of the field, it covers the international and national standards that guide the quality of air sampling measurements and equipment. It discusses emergency response issues, including radioactive fallout and the assets used ...

  6. Sensitivity Increases for the TITAN Decay Spectroscopy Program

    Directory of Open Access Journals (Sweden)

    Leach K.G.

    2015-01-01

    Full Text Available The TITAN facility at TRIUMF has recently initiated a program of performing decay spectroscopy measurements in an electron-beam ion-trap (EBIT. The unique environment of the EBIT provides backingfree storage of the radioactive ions, while guiding charged decay particles from the trap centre via the strong magnetic field. This measurement technique is able to provide a significant increase in detection sensitivity for photons which result from radioactive decay. A brief overview of this device is presented, along with methods of improving the signal-to-background ratio for photon detection by reducing Compton scattered events, and eliminating vibrational noise.

  7. Sensitivity Increases for the TITAN Decay Spectroscopy Program

    CERN Document Server

    Leach, K G; Grossheim, A; Andreoiu, C; Dilling, J; Frekers, D; Good, M; Seeraji, S

    2014-01-01

    The TITAN facility at TRIUMF has recently initiated a program of performing decay spectroscopy measurements in an electron-beam ion-trap (EBIT). The unique environment of the EBIT provides backing-free storage of the radioactive ions, while guiding charged decay particles from the trap centre via the strong magnetic field. This measurement technique is able to provide a significant increase in detection sensitivity for photons which result from radioactive decay. A brief overview of this device is presented, along with methods of improving the signal-to-background ratio for photon detection by reducing Compton scattered events, and eliminating vibrational noise.

  8. Radioactive ion beam development in Berkeley

    CERN Document Server

    Wutte, D C; Leitner, M A; Xie, Z Q

    1999-01-01

    Two radioactive ion beam projects are under development at the 88" Cyclotron, BEARS (Berkeley Experiment with accelerated radioactive species) and the 14O experiment. The projects are initially focused on the production of 11C and 14O, but it is planned to expand the program to 17F, 18F, 13N and 76Kr. For the BEARS project, the radioactivity is produced in form of either CO2 or N2O in a small medical 10 MeV proton cyclotron. The activity is then transported through a 300 m long He-jet line to the 88" cyclotron building, injected into the AECR-U ion source and accelerated through the 88" cyclotron to energies between 1 to 30 MeV/ nucleon. The 14O experiment is a new experiment at the 88" cyclotron to measure the energy-shape of the beta decay spectrum. For this purpose, a target transfer line and a radioactive ion beam test stand has been constructed. The radioactivity is produced in form of CO in a hot carbon target with a 20 MeV 3He from the 88" Cyclotron. The activity diffuses through an 8m long stainless s...

  9. Radioactivity and its measurement

    CERN Document Server

    Mann, W B; Garfinkel, S B

    1980-01-01

    Begins with a description of the discovery of radioactivity and the historic research of such pioneers as the Curies and Rutherford. After a discussion of the interactions of &agr;, &bgr; and &ggr; rays with matter, the energetics of the different modes of nuclear disintegration are considered in relation to the Einstein mass-energy relationship as applied to radioactive transformations. Radiation detectors and radioactivity measurements are also discussed

  10. QCD Factorization Based on Six-Quark Operator Effective Hamiltonian from Perturbative QCD and Charmless Bottom Meson Decays $B_{(s)}\\to \\pi\\pi,\\pi K, KK$

    CERN Document Server

    Su, Fang; Yang, Yi-Bo; Zhuang, Ci

    2008-01-01

    The charmless bottom meson decays are systematically investigated based on an approximate six quark operator effective Hamiltonian from perturbative QCD. It is shown that within this framework the naive QCD factorization method provides a simple way to evaluate the hadronic matrix elements of two body mesonic decays. The singularities caused by on mass-shell quark propagator and gluon exchanging interaction are appropriately treated. Such a simple framework allows us to make theoretical predictions for the decay amplitudes with reasonable input parameters. The resulting theoretical predictions for all the branching ratios and CP asymmetries in the charmless $B^0, B^+, B_s\\to \\pi\\pi, \\pi K, KK$ decays are found to be consistent with the current experimental data except for a few decay modes. The observed large branching ratio in $B\\to \\pi^0\\pi^0$ decay remains a puzzle though the predicted branching ratio may be significantly improved by considering the large vertex corrections in the effective Wilson coeffici...

  11. New approach for alpha decay half-lives of superheavy nuclei and applicability of WKB approximation

    Science.gov (United States)

    Dong, Jianmin; Zuo, Wei; Scheid, Werner

    2011-07-01

    The α decay half-lives of recently synthesized superheavy nuclei (SHN) are calculated by applying a new approach which estimates them with the help of their neighbors based on some simple formulas. The estimated half-life values are in very good agreement with the experimental ones, indicating the reliability of the experimental observations and measurements to a large extent as well as the predictive power of our approach. The second part of this work is to test the applicability of the Wentzel-Kramers-Brillouin (WKB) approximation for the quantum mechanical tunneling probability. We calculated the accurate barrier penetrability for alpha decay along with proton and cluster radioactivity by numerically solving Schrödinger equation. The calculated results are compared with those of the WKB method to find that WKB approximation works well for the three physically analogical decay modes.

  12. New approach for alpha decay half-lives of superheavy nuclei and applicability of WKB approximation

    Energy Technology Data Exchange (ETDEWEB)

    Dong Jianmin [Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Institute for Theoretical Physics, Justus Liebig University, D-35392 Giessen (Germany); China Institute of Atomic Energy, P.O. Box 275(18), Beijing 102413 (China); Zuo Wei, E-mail: zuowei@impcas.ac.cn [Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000 (China); School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Scheid, Werner [Institute for Theoretical Physics, Justus Liebig University, D-35392 Giessen (Germany)

    2011-07-01

    The {alpha} decay half-lives of recently synthesized superheavy nuclei (SHN) are calculated by applying a new approach which estimates them with the help of their neighbors based on some simple formulas. The estimated half-life values are in very good agreement with the experimental ones, indicating the reliability of the experimental observations and measurements to a large extent as well as the predictive power of our approach. The second part of this work is to test the applicability of the Wentzel-Kramers-Brillouin (WKB) approximation for the quantum mechanical tunneling probability. We calculated the accurate barrier penetrability for alpha decay along with proton and cluster radioactivity by numerically solving Schroedinger equation. The calculated results are compared with those of the WKB method to find that WKB approximation works well for the three physically analogical decay modes.

  13. New approach for alpha decay half-lives of superheavy nuclei and applicability of WKB approximation

    CERN Document Server

    Dong, Jianmin; Scheid, Werner; 10.1016/j.nuclphysa.2011.06.016

    2011-01-01

    The alpha decay half-lives of recently synthesized superheavy nuclei (SHN) are calculated by applying a new approach which estimates them with the help of their neighbors based on some simple formulas. The estimated half-life values are in very good agreement with the experimental ones, indicating the reliability of the experimental observations and measurements to a large extent as well as the predictive power of our approach. The second part of this work is to test the applicability of the Wentzel-Kramers-Brillouin (WKB) approximation for the quantum mechanical tunneling probability. We calculated the accurate barrier penetrability for alpha decay along with proton and cluster radioactivity by numerically solving Schr\\"odinger equation. The calculated results are compared with those of the WKB method to find that WKB approximation works well for the three physically analogical decay modes.

  14. Application of Origen2.1 in the decay photon spectrum calculation of spallation products

    CERN Document Server

    Hong, Shuang; Xu, Hu-Shan; Meng, Hai-Yan; Zhang, Lu; Liu, Zhao-Qing; Gao, Yu-Cui; Chen, Kang

    2016-01-01

    Origen2.1 is a widely used computer code for calculating the burnup, decay, and processing of radioactive materials. However, the nuclide library of Origen2.1 is used for existing reactors like pressurized water reactor, to calculate the photon spectrum released by the decay of spallation products, we have made specific libraries for the ADS tungsten spallation target, based on the results given by a Monte Carlo code: FLUKA. All the data used to make the Origen2.1 libraries is obtained from Nuclear structure & decay Data (NuDat2.6). The accumulated activity of spallation products and the contribution of nuclides to photon emission are given in this paper.

  15. Radioactivity in the galactic plane

    Science.gov (United States)

    Walraven, G. D.; Haymes, R. C.

    1976-01-01

    The paper reports the detection of a large concentration of interstellar radioactivity during balloon-altitude measurements of gamma-ray energy spectra in the band between 0.02 and 12.27 MeV from galactic and extragalactic sources. Enhanced counting rates were observed in three directions towards the plane of the Galaxy; a power-law energy spectrum is computed for one of these directions (designated B 10). A large statistical deviation from the power law in a 1.0-FWHM interval centered near 1.16 MeV is discussed, and the existence of a nuclear gamma-ray line at 1.15 MeV in B 10 is postulated. It is suggested that Ca-44, which emits gamma radiation at 1.156 MeV following the decay of radioactive Sc-44, is a likely candidate for this line, noting that Sc-44 arises from Ti-44 according to explosive models of supernova nucleosynthesis. The 1.16-MeV line flux inferred from the present data is shown to equal the predicted flux for a supernova at a distance of approximately 3 kpc and an age not exceeding about 100 years.

  16. Shower hodoscope detector calibration based on. pi. /sup 0/- and eta-mesons decay into two gamma-quanta

    Energy Technology Data Exchange (ETDEWEB)

    Akimenko, S.A.; Belousov, V.I.; Blik, A.M.; Kolosov, V.N.; Kut' in, V.M.; Palinov, A.I.; Solov' ev, A.S. (Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Serpukhov. Inst. Fiziki Vysokikh Ehnergij); Bannikov, A.V.; Krumshtejn, Z.V. (Joint Inst. for Nuclear Research, Dubna (USSR))

    Shower hodoscope detector, containing 49 units of lead glass with total volume of 1.4x1.4x0.35 m/sup 3/ has been described and the method of the detector calibration based on the use of ..pi.. deg (eta) ..-->.. 2 ..gamma.. decays has been considered. The calibration is aimed at the setting of counting spacing of amplitude transducer epsilon sub(i). In the suggested way of calibration according to resonances the attribution of the coefficients epsilon sub(i) directly to the values of table masses of neutral mesons is realized, whereas after the calibration on electron beam the account of certain difference between e- and ..gamma..-showers, effects of incomplete absorption etc. is necessary. Similar algorithms can be developed for resonances in the system of more than two ..gamma..-quanta.

  17. Chromatographic separation of radioactive noble gases from xenon

    CERN Document Server

    Akerib, D S; Bai, X; Bailey, A J; Balajthy, J; Beltrame, P; Bernard, E P; Bernstein, A; Biesiadzinski, T P; Boulton, E M; Bramante, R; Cahn, S B; Carmona-Benitez, M C; Chan, C; Chiller, A A; Chiller, C; Coffey, T; Currie, A; Cutter, J E; Davison, T J R; Dobi, A; Dobson, J E Y; Druszkiewicz, E; Edwards, B N; Faham, C H; Fiorucci, S; Gaitskell, R J; Gehman, V M; Ghag, C; Gibson, K R; Gilchriese, M G D; Hall, C R; Hanhardt, M; Haselschwardt, S J; Hertel, S A; Hogan, D P; Horn, M; Huang, D Q; Ignarra, C M; Ihm, M; Jacobsen, R G; Ji, W; Kamdin, K; Kazkaz, K; Khaitan, D; Knoche, R; Larsen, N A; Lee, C; Lenardo, B G; Lesko, K T; Lindote, A; Lopes, M I; Manalaysay, A; Mannino, R L; Marzioni, M F; McKinsey, D N; Mei, D -M; Mock, J; Moongweluwan, M; Morad, J A; Murphy, A St J; Nehrkorn, C; Nelson, H N; Neves, F; O'Sullivan, K; Oliver-Mallory, K C; Palladino, K J; Pease, E K; Pech, K; Phelps, P; Reichhart, L; Rhyne, C; Shaw, S; Shutt, T A; Silva, C; Solovov, V N; Sorensen, P; Stephenson, S; Sumner, T J; Szydagis, M; Taylor, D J; Taylor, W; Tennyson, B P; Terman, P A; Tiedt, D R; To, W H; Tripathi, M; Tvrznikova, L; Uvarov, S; Verbus, J R; Webb, R C; White, J T; Whitis, T J; Witherell, M S; Wolfs, F L H; Yazdani, K; Young, S K; Zhang, C

    2016-01-01

    The Large Underground Xenon (LUX) experiment operates at the Sanford Underground Research Facility to detect nuclear recoils from the hypothetical Weakly Interacting Massive Particles (WIMPs) on a liquid xenon target. Liquid xenon typically contains trace amounts of the noble radioactive isotopes $^{85}$Kr and $^{39}$Ar that are not removed by the {\\em in situ} gas purification system. The decays of these isotopes at concentrations typical of research-grade xenon would be a dominant background for a WIMP search exmperiment. To remove these impurities from the liquid xenon, a chromatographic separation system based on adsorption on activated charcoal was built. 400\\,kg of xenon was processed, reducing the average concentration of krypton from 130\\,ppb to 3.5\\,ppt as measured by a cold-trap assisted mass spectroscopy system. A 50 kg batch spiked to 0.001 g/g of krypton was processed twice and reduced to an upper limit of 0.2 ppt.

  18. Measurement of the Perturbation of the Decay Rate of ~7Be

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    ~7Be is the lightest radioactive nucleus that decays by electron capture. It is a good candidate used forlooking for perturbation of nuclear decay rates because of its simple electronic structure : 1s~22s~2.Furthermore, the decay rate of ~7Be shows its importance in some fields such as basic nuclear physics,

  19. Induced radioactivity at CERN

    CERN Multimedia

    1970-01-01

    A description of some of the problems and some of the advantages associated with the phenomenon of induced radioactivity at accelerator centres such as CERN. The author has worked in this field for several years and has recently written a book 'Induced Radioactivity' published by North-Holland.

  20. A Remote Radioactivity Experiment

    Science.gov (United States)

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one…

  1. Influence of radioactivity on surface charging and aggregation kinetics of particles in the atmosphere.

    Science.gov (United States)

    Kim, Yong-Ha; Yiacoumi, Sotira; Lee, Ida; McFarlane, Joanna; Tsouris, Costas

    2014-01-01

    Radioactivity can influence surface interactions, but its effects on particle aggregation kinetics have not been included in transport modeling of radioactive particles. In this research, experimental and theoretical studies have been performed to investigate the influence of radioactivity on surface charging and aggregation kinetics of radioactive particles in the atmosphere. Radioactivity-induced charging mechanisms have been investigated at the microscopic level, and heterogeneous surface potential caused by radioactivity is reported. The radioactivity-induced surface charging is highly influenced by several parameters, such as rate and type of radioactive decay. A population balance model, including interparticle forces, has been employed to study the effects of radioactivity on particle aggregation kinetics in air. It has been found that radioactivity can hinder aggregation of particles because of similar surface charging caused by the decay process. Experimental and theoretical studies provide useful insights into the understanding of transport characteristics of radioactive particles emitted from severe nuclear events, such as the recent accident of Fukushima or deliberate explosions of radiological devices.

  2. Environmental radioactivity survey data in Cheonju

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Mo Sung; Goo, Hyun Mi [Cheongju Univ., Cheongju (Korea, Republic of)

    2003-12-15

    We surveyed the en environmental radiation and radioactivity in Chungcheongbuk-do in order to provide baseline data in the year of 2003. Data generated from the project will be the information base for making decisions necessary to ensure the protection of public health. This report contains the data of gamma exposure rates and radioactivities of airborne dust, fallout, precipitation and tap water which were analyzed periodically by Cheongju regional monitoring station In the year 2003. Also it contains the data of natural radioactivity levels of environmental samples such as soil, drinking water, indicator plant(mugwort, pine-needle), agricultural and forest products, and processed food(tea)

  3. Assessment of the disposal of radioactive petroleum industry waste in nonhazardous landfills using risk-based modeling.

    Science.gov (United States)

    Smith, Karen P; Arnish, John J; Williams, Gustavious P; Blunt, Deborah L

    2003-05-15

    Certain petroleum production activities cause naturally occurring radioactive materials (NORM) to accumulate in concentrations above natural background levels, making safe and cost-effective management of such technologically enhanced NORM (TENORM) a key issue for the petroleum industry. As a result, both industry and regulators are interested in identifying cost-effective disposal alternatives that provide adequate protection of human health and the environment One such alternative, currently allowed in Michigan with restrictions, is the disposal of TENORM wastes in nonhazardous waste landfills. The disposal of petroleum industry wastes containing radium-226 (Ra-226) in nonhazardous landfills was modeled to evaluate the potential radiological doses and health risks to workers and the public. Multiple scenarios were considered in evaluating the potential risks associated with landfill operations and the future use of the property. The scenarios were defined, in part, to evaluate the Michigan policy; sensitivity analyses were conducted to evaluate the impact of key parameters on potential risks. The results indicate that the disposal of petroleum industry TENORM wastes in nonhazardous landfills in accordance with the Michigan policy and existing landfill regulations presents a negligible risk to most of the potential receptors considered in this study.

  4. Extraction of radioactive positive ions across the surface of superfluid helium : A new method to produce cold radioactive nuclear beams

    NARCIS (Netherlands)

    Huang, WX; Dendooven, P; Gloos, K; Takahashi, N; Pekola, JP; Aysto, J

    2003-01-01

    Alpha-decay recoils Rn-219 were stopped in superfluid helium and positive ions were extracted by electric field into the vapour phase. This first quantitative observation of extraction was successfully conducted using highly sensitive radioactivity detection. The efficiency for extraction across the

  5. Radioactivity; La radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This pedagogical document presents the origin, effects and uses of radioactivity: where does radioactivity comes from, effects on the body, measurement, protection against radiations, uses in the medical field, in the electric power industry, in the food (ionization, radio-mutagenesis, irradiations) and other industries (radiography, gauges, detectors, irradiations, tracers), and in research activities (dating, preservation of cultural objects). The document ends with some examples of irradiation levels (examples of natural radioactivity, distribution of the various sources of exposure in France). (J.S.)

  6. Natural radioactivity in groundwater--a review.

    Science.gov (United States)

    Dinh Chau, Nguyen; Dulinski, Marek; Jodlowski, Pawel; Nowak, Jakub; Rozanski, Kazimierz; Sleziak, Monika; Wachniew, Przemyslaw

    2011-12-01

    The issue of natural radioactivity in groundwater is reviewed, with emphasis on those radioisotopes which contribute in a significant way to the overall effective dose received by members of the public due to the intake of drinking water originating from groundwater systems. The term 'natural radioactivity' is used in this context to cover all radioactivity present in the environment, including man-made (anthropogenic) radioactivity. Comprehensive discussion of radiological aspects of the presence of natural radionuclides in groundwater, including an overview of current regulations dealing with radioactivity in drinking water, is provided. The presented data indicate that thorough assessments of the committed doses resulting from the presence of natural radioactivity in groundwater are needed, particularly when such water is envisaged for regular intake by infants. They should be based on a precise determination of radioactivity concentration levels of the whole suite of radionuclides, including characterisation of their temporal variability. Equally important is a realistic assessment of water intake values for specific age groups. Only such an evaluation may provide the basis for possible remedial actions.

  7. Endangered and Extinct Radioactivity

    Science.gov (United States)

    Leising, M. D.

    1993-07-01

    Gamma ray spectroscopy holds great promise for probing nucleosynthesis in individual nucleosynthesis events, via observations of short-lived radioactivity, and for measuring global galactic nucleosynthesis today with detections of longer-lived radioactivity. Many of the astrophysical issues addressed by these observations are precisely those that must be understood in order to interpret observations of extinct radioactivity in meteorites. It was somewhat surprising that the former case was realized first for a Type II supernova, when both 56Co [1] and 57Co [2] were detected in SN 1987A. These provide unprecedented constraints on models of Type II explosions. Live 26Al in the galaxy might come from Type II supernovae and their progenitors, and if this is eventually shown to be the case, can constrain massive star evolution, supernova nucleosynthesis, the galactic Type II supernova rate, and even models of the chemical evolution of the galaxy [3]. Titanium-44 is produced primarily in the alpha-rich freezeout from nuclear statistical equilibrium, possibly in Type Ia [4] and almost certainly in Type II supernovae [5]. The galactic recurrence time of these events is comparable to the 44Ti lifetime, so we expect to be able to see at most a few otherwise unseen 44Ti remnants at any given time. No such remnants have been detected yet [6]. Very simple arguments lead to the expectation that about 4 x 10^-4 M(sub)solar mass of 44Ca are produced per century. The product of the supernova frequency times the 44Ti yield per event must equal this number. Even assuming that only the latest event would be seen, rates in excess of 2 century^-1 are ruled out at >=99% confidence by the gamma ray limits. Only rates less than 0.3 century^-1 are acceptable at >5% confidence, and this means that the yield per event must be >10^-3 M(sub)solar mass to produce the requisite 44Ca. Rates this low are incompatible with current estimates for Type II supernovae and yields this high are also very

  8. Nuclear astrophysics with radioactive ions at FAIR

    CERN Document Server

    Reifarth, R; Göbel, K; Heftrich, T; Heil, M; Koloczek, A; Langer, C; Plag, R; Pohl, M; Sonnabend, K; Weigand, M; Adachi, T; Aksouh, F; Al-Khalili, J; AlGarawi, M; AlGhamdi, S; Alkhazov, G; Alkhomashi, N; Alvarez-Pol, H; Alvarez-Rodriguez, R; Andreev, V; Andrei, B; Atar, L; Aumann, T; Avdeichikov, V; Bacri, C; Bagchi, S; Barbieri, C; Beceiro, S; Beck, C; Beinrucker, C; Belier, G; Bemmerer, D; Bendel, M; Benlliure, J; Benzoni, G; Berjillos, R; Bertini, D; Bertulani, C; Bishop, S; Blasi, N; Bloch, T; Blumenfeld, Y; Bonaccorso, A; Boretzky, K; Botvina, A; Boudard, A; Boutachkov, P; Boztosun, I; Bracco, A; Brambilla, S; Monago, J Briz; Caamano, M; Caesar, C; Camera, F; Casarejos, E; Catford, W; Cederkall, J; Cederwall, B; Chartier, M; Chatillon, A; Cherciu, M; Chulkov, L; Coleman-Smith, P; Cortina-Gil, D; Crespi, F; Crespo, R; Cresswell, J; Csatlós, M; Déchery, F; Davids, B; Davinson, T; Derya, V; Detistov, P; Fernandez, P Diaz; DiJulio, D; Dmitry, S; Doré, D; nas, J Due\\; Dupont, E; Egelhof, P; Egorova, I; Elekes, Z; Enders, J; Endres, J; Ershov, S; Ershova, O; Fernandez-Dominguez, B; Fetisov, A; Fiori, E; Fomichev, A; Fonseca, M; Fraile, L; Freer, M; Friese, J; Borge, M G; Redondo, D Galaviz; Gannon, S; Garg, U; Gasparic, I; Gasques, L; Gastineau, B; Geissel, H; Gernhäuser, R; Ghosh, T; Gilbert, M; Glorius, J; Golubev, P; Gorshkov, A; Gourishetty, A; Grigorenko, L; Gulyas, J; Haiduc, M; Hammache, F; Harakeh, M; Hass, M; Heine, M; Hennig, A; Henriques, A; Herzberg, R; Holl, M; Ignatov, A; Ignatyuk, A; Ilieva, S; Ivanov, M; Iwasa, N; Jakobsson, B; Johansson, H; Jonson, B; Joshi, P; Junghans, A; Jurado, B; Körner, G; Kalantar, N; Kanungo, R; Kelic-Heil, A; Kezzar, K; Khan, E; Khanzadeev, A; Kiselev, O; Kogimtzis, M; Körper, D; Kräckmann, S; Kröll, T; Krücken, R; Krasznahorkay, A; Kratz, J; Kresan, D; Krings, T; Krumbholz, A; Krupko, S; Kulessa, R; Kumar, S; Kurz, N; Kuzmin, E; Labiche, M; Langanke, K; Lazarus, I; Bleis, T Le; Lederer, C; Lemasson, A; Lemmon, R; Liberati, V; Litvinov, Y; Löher, B; Herraiz, J Lopez; Münzenberg, G; Machado, J; Maev, E; Mahata, K; Mancusi, D; Marganiec, J; Perez, M Martinez; Marusov, V; Mengoni, D; Million, B; Morcelle, V; Moreno, O; Movsesyan, A; Nacher, E; Najafi, M; Nakamura, T; Naqvi, F; Nikolski, E; Nilsson, T; Nociforo, C; Nolan, P; Novatsky, B; Nyman, G; Ornelas, A; Palit, R; Pandit, S; Panin, V; Paradela, C; Parkar, V; Paschalis, S; Paw\\lowski, P; Perea, A; Pereira, J; Petrache, C; Petri, M; Pickstone, S; Pietralla, N; Pietri, S; Pivovarov, Y; Potlog, P; Prokofiev, A; Rastrepina, G; Rauscher, T; Ribeiro, G; Ricciardi, M; Richter, A; Rigollet, C; Riisager, K; Rios, A; Ritter, C; Frutos, T Rodríguez; Vignote, J Rodriguez; Röder, M; Romig, C; Rossi, D; Roussel-Chomaz, P; Rout, P; Roy, S; Söderström, P; Sarkar, M Saha; Sakuta, S; Salsac, M; Sampson, J; Saez, J Sanchez del Rio; Rosado, J Sanchez; Sanjari, S; Sarriguren, P; Sauerwein, A; Savran, D; Scheidenberger, C; Scheit, H; Schmidt, S; Schmitt, C; Schnorrenberger, L; Schrock, P; Schwengner, R; Seddon, D; Sherrill, B; Shrivastava, A; Sidorchuk, S; Silva, J; Simon, H; Simpson, E; Singh, P; Slobodan, D; Sohler, D; Spieker, M; Stach, D; Stan, E; Stanoiu, M; Stepantsov, S; Stevenson, P; Strieder, F; Stuhl, L; Suda, T; Sümmerer, K; Streicher, B; Taieb, J; Takechi, M; Tanihata, I; Taylor, J; Tengblad, O; Ter-Akopian, G; Terashima, S; Teubig, P; Thies, R; Thoennessen, M; Thomas, T; Thornhill, J; Thungstrom, G; Timar, J; Togano, Y; Tomohiro, U; Tornyi, T; Tostevin, J; Townsley, C; Trautmann, W; Trivedi, T; Typel, S; Uberseder, E; Udias, J; Uesaka, T; Uvarov, L; Vajta, Z; Velho, P; Vikhrov, V; Volknandt, M; Volkov, V; von Neumann-Cosel, P; von Schmid, M; Wagner, A; Wamers, F; Weick, H; Wells, D; Westerberg, L; Wieland, O; Wiescher, M; Wimmer, C; Wimmer, K; Winfield, J S; Winkel, M; Woods, P; Wyss, R; Yakorev, D; Yavor, M; Cardona, J Zamora; Zartova, I; Zerguerras, T; Zgura, I; Zhdanov, A; Zhukov, M; Zieblinski, M; Zilges, A; Zuber, K

    2016-01-01

    The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes.

  9. Nuclear astrophysics with radioactive ions at FAIR

    Science.gov (United States)

    Reifarth, R.; Altstadt, S.; Göbel, K.; Heftrich, T.; Heil, M.; Koloczek, A.; Langer, C.; Plag, R.; Pohl, M.; Sonnabend, K.; Weigand, M.; Adachi, T.; Aksouh, F.; Al-Khalili, J.; AlGarawi, M.; AlGhamdi, S.; Alkhazov, G.; Alkhomashi, N.; Alvarez-Pol, H.; Alvarez-Rodriguez, R.; Andreev, V.; Andrei, B.; Atar, L.; Aumann, T.; Avdeichikov, V.; Bacri, C.; Bagchi, S.; Barbieri, C.; Beceiro, S.; Beck, C.; Beinrucker, C.; Belier, G.; Bemmerer, D.; Bendel, M.; Benlliure, J.; Benzoni, G.; Berjillos, R.; Bertini, D.; Bertulani, C.; Bishop, S.; Blasi, N.; Bloch, T.; Blumenfeld, Y.; Bonaccorso, A.; Boretzky, K.; Botvina, A.; Boudard, A.; Boutachkov, P.; Boztosun, I.; Bracco, A.; Brambilla, S.; Briz Monago, J.; Caamano, M.; Caesar, C.; Camera, F.; Casarejos, E.; Catford, W.; Cederkall, J.; Cederwall, B.; Chartier, M.; Chatillon, A.; Cherciu, M.; Chulkov, L.; Coleman-Smith, P.; Cortina-Gil, D.; Crespi, F.; Crespo, R.; Cresswell, J.; Csatlós, M.; Déchery, F.; Davids, B.; Davinson, T.; Derya, V.; Detistov, P.; Diaz Fernandez, P.; DiJulio, D.; Dmitry, S.; Doré, D.; Dueñas, J.; Dupont, E.; Egelhof, P.; Egorova, I.; Elekes, Z.; Enders, J.; Endres, J.; Ershov, S.; Ershova, O.; Fernandez-Dominguez, B.; Fetisov, A.; Fiori, E.; Fomichev, A.; Fonseca, M.; Fraile, L.; Freer, M.; Friese, J.; Borge, M. G.; Galaviz Redondo, D.; Gannon, S.; Garg, U.; Gasparic, I.; Gasques, L.; Gastineau, B.; Geissel, H.; Gernhäuser, R.; Ghosh, T.; Gilbert, M.; Glorius, J.; Golubev, P.; Gorshkov, A.; Gourishetty, A.; Grigorenko, L.; Gulyas, J.; Haiduc, M.; Hammache, F.; Harakeh, M.; Hass, M.; Heine, M.; Hennig, A.; Henriques, A.; Herzberg, R.; Holl, M.; Ignatov, A.; Ignatyuk, A.; Ilieva, S.; Ivanov, M.; Iwasa, N.; Jakobsson, B.; Johansson, H.; Jonson, B.; Joshi, P.; Junghans, A.; Jurado, B.; Körner, G.; Kalantar, N.; Kanungo, R.; Kelic-Heil, A.; Kezzar, K.; Khan, E.; Khanzadeev, A.; Kiselev, O.; Kogimtzis, M.; Körper, D.; Kräckmann, S.; Kröll, T.; Krücken, R.; Krasznahorkay, A.; Kratz, J.; Kresan, D.; Krings, T.; Krumbholz, A.; Krupko, S.; Kulessa, R.; Kumar, S.; Kurz, N.; Kuzmin, E.; Labiche, M.; Langanke, K.; Lazarus, I.; Le Bleis, T.; Lederer, C.; Lemasson, A.; Lemmon, R.; Liberati, V.; Litvinov, Y.; Löher, B.; Lopez Herraiz, J.; Münzenberg, G.; Machado, J.; Maev, E.; Mahata, K.; Mancusi, D.; Marganiec, J.; Martinez Perez, M.; Marusov, V.; Mengoni, D.; Million, B.; Morcelle, V.; Moreno, O.; Movsesyan, A.; Nacher, E.; Najafi, M.; Nakamura, T.; Naqvi, F.; Nikolski, E.; Nilsson, T.; Nociforo, C.; Nolan, P.; Novatsky, B.; Nyman, G.; Ornelas, A.; Palit, R.; Pandit, S.; Panin, V.; Paradela, C.; Parkar, V.; Paschalis, S.; Pawłowski, P.; Perea, A.; Pereira, J.; Petrache, C.; Petri, M.; Pickstone, S.; Pietralla, N.; Pietri, S.; Pivovarov, Y.; Potlog, P.; Prokofiev, A.; Rastrepina, G.; Rauscher, T.; Ribeiro, G.; Ricciardi, M.; Richter, A.; Rigollet, C.; Riisager, K.; Rios, A.; Ritter, C.; Rodriguez Frutos, T.; Rodriguez Vignote, J.; Röder, M.; Romig, C.; Rossi, D.; Roussel-Chomaz, P.; Rout, P.; Roy, S.; Söderström, P.; Saha Sarkar, M.; Sakuta, S.; Salsac, M.; Sampson, J.; Sanchez, J.; Rio Saez, del; Sanchez Rosado, J.; Sanjari, S.; Sarriguren, P.; Sauerwein, A.; Savran, D.; Scheidenberger, C.; Scheit, H.; Schmidt, S.; Schmitt, C.; Schnorrenberger, L.; Schrock, P.; Schwengner, R.; Seddon, D.; Sherrill, B.; Shrivastava, A.; Sidorchuk, S.; Silva, J.; Simon, H.; Simpson, E.; Singh, P.; Slobodan, D.; Sohler, D.; Spieker, M.; Stach, D.; Stan, E.; Stanoiu, M.; Stepantsov, S.; Stevenson, P.; Strieder, F.; Stuhl, L.; Suda, T.; Sümmerer, K.; Streicher, B.; Taieb, J.; Takechi, M.; Tanihata, I.; Taylor, J.; Tengblad, O.; Ter-Akopian, G.; Terashima, S.; Teubig, P.; Thies, R.; Thoennessen, M.; Thomas, T.; Thornhill, J.; Thungstrom, G.; Timar, J.; Togano, Y.; Tomohiro, U.; Tornyi, T.; Tostevin, J.; Townsley, C.; Trautmann, W.; Trivedi, T.; Typel, S.; Uberseder, E.; Udias, J.; Uesaka, T.; Uvarov, L.; Vajta, Z.; Velho, P.; Vikhrov, V.; Volknandt, M.; Volkov, V.; von Neumann-Cosel, P.; von Schmid, M.; Wagner, A.; Wamers, F.; Weick, H.; Wells, D.; Westerberg, L.; Wieland, O.; Wiescher, M.; Wimmer, C.; Wimmer, K.; Winfield, J. S.; Winkel, M.; Woods, P.; Wyss, R.; Yakorev, D.; Yavor, M.; Zamora Cardona, J.; Zartova, I.; Zerguerras, T.; Zgura, M.; Zhdanov, A.; Zhukov, M.; Zieblinski, M.; Zilges, A.; Zuber, K.

    2016-01-01

    The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process, β-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes.

  10. Determination of the compound nucleus survival probability Psurv for various "hot" fusion reactions based on the dynamical cluster-decay model

    Science.gov (United States)

    Chopra, Sahila; Kaur, Arshdeep; Gupta, Raj K.

    2015-03-01

    After a successful attempt to define and determine recently the compound nucleus (CN) fusion/ formation probability PCN within the dynamical cluster-decay model (DCM), we introduce and estimate here for the first time the survival probability Psurv of CN against fission, again within the DCM. Calculated as the dynamical fragmentation process, Psurv is defined as the ratio of the evaporation residue (ER) cross section σER and the sum of σER and fusion-fission (ff) cross section σff, the CN formation cross section σCN, where each contributing fragmentation cross section is determined in terms of its formation and barrier penetration probabilities P0 and P . In DCM, the deformations up to hexadecapole and "compact" orientations for both in-plane (coplanar) and out-of-plane (noncoplanar) configurations are allowed. Some 16 "hot" fusion reactions, forming a CN of mass number ACN˜100 to superheavy nuclei, are analyzed for various different nuclear interaction potentials, and the variation of Psurv on CN excitation energy E*, fissility parameter χ , CN mass ACN, and Coulomb parameter Z1Z2 is investigated. Interesting results are that three groups, namely, weakly fissioning, radioactive, and strongly fissioning superheavy nuclei, are identified with Psurv, respectively, ˜1 ,˜10-6 , and ˜10-10 . For the weakly fissioning group (100 PCN belongs to the strongly fissioning superheavy group, Psurv belongs to weakly fissioning nuclei; for Pt* isotopes, the inverse of all the compound systems studied, both PCN and Psurv decrease with the increase of E*; for 213 ,215 ,217Fr* nuclei, though fissility χ is nearly the same, Psurv for 213 ,217Fr* is of the same order as for weakly fissioning nuclei, but that for 215Fr* is of the order of radioactive nuclei. Apparently, further calculations are called for.

  11. In-Trap Spectroscopy of Charge-Bred Radioactive Ions

    Science.gov (United States)

    Lennarz, A.; Grossheim, A.; Leach, K. G.; Alanssari, M.; Brunner, T.; Chaudhuri, A.; Chowdhury, U.; Crespo López-Urrutia, J. R.; Gallant, A. T.; Holl, M.; Kwiatkowski, A. A.; Lassen, J.; Macdonald, T. D.; Schultz, B. E.; Seeraji, S.; Simon, M. C.; Andreoiu, C.; Dilling, J.; Frekers, D.

    2014-08-01

    In this Letter, we introduce the concept of in-trap nuclear decay spectroscopy of highly charged radioactive ions and describe its successful application as a novel spectroscopic tool. This is demonstrated by a measurement of the decay properties of radioactive mass A=124 ions (here, In124 and Cs124) in the electron-beam ion trap of the TITAN facility at TRIUMF. By subjecting the trapped ions to an intense electron beam, the ions are charge bred to high charge states (i.e., equivalent to the removal of N-shell electrons), and an increase of storage times to the level of minutes without significant ion losses is achieved. The present technique opens the venue for precision spectroscopy of low branching ratios and is being developed in the context of measuring electron-capture branching ratios needed for determining the nuclear ground-state properties of the intermediate odd-odd nuclei in double-beta (ββ) decay.

  12. Understanding radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Murray, R.L.

    1981-12-01

    This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes). (ATT)

  13. Near-field investigation of the explosive dispersal of radioactive material based on a reconstructed spherical blast-wave flow.

    Science.gov (United States)

    Hummel, David; Ivan, Lucian

    2017-03-15

    A "dirty bomb" is a type of radiological dispersal device (RDD) that has been the subject of significant safety and security concerns given the disruption that would result from a postulated terrorist attack. Assessing the risks of radioactive dose in a hypothetical scenario requires models that can accurately predict dispersion in a realistic environment. Modelling a RDD is complicated by the fact that the most important phenomena occur over vastly disparate spatial and temporal length scales. Particulate dispersion in the air is generally considered on scales of hundreds to thousands of meters, and over periods of minutes and hours. Dispersion models are extremely sensitive, however, to the particle size and source characterization, which are determined in distances measured in micrometers to meters, over milliseconds or less. This study examines the extent to which the explosive blast determines the transport of contaminant particles relative to the atmospheric wind over distances relevant to "near-field" dispersion problems (i.e., hundreds of meters), which are relevant to urban environments. Our results indicate that whether or not the effect of the blast should be included in a near-field dispersion model is largely dependent on the size of the contaminant particle. Relatively large particles (i.e., >40 μm in diameter), which are most likely to be produced by a RDD, penetrate the leading shock front, thereby avoiding the reverse blast wind. Consequently, they travel much farther than suspended aerosols (<10 μm) before approaching the ambient wind velocity. This suggests that, for these "near-field" dispersion problems in urban environments, the transport of contaminants from the blast wave may be integral to accurately predicting their dispersion.

  14. Radioactive isotopes in Danish drinking water

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Sven P. [Risoe National Lab., Roskilde (Denmark)

    2006-08-31

    A screening investigation of radioactivity in Danish drinking water has been carried out during 2001-2003. Samples of drinking water were collected from 296 water supplies representing more than 40% of the water delivered from water works in the country. Total alpha and total beta radioactivity was determined in the samples and compared with screening levels of 0.1 Bq/l total alpha and 1 Bq/l total beta radioactivity. The levels for total beta radioactivity were met in all the water works while total alpha radioactivity exceeded the screening levels for 13 water supplies. Further investigations were carried out for the water works with concentrations of alpha radioactivity above the screening levels in Ebeltoft, Grenae and Frederikssund to estimate the total indicative dose from the water. The elevated levels were found to be due to uranium in the water from individual boreholes. Radiation doses from consumption of water at these uranium levels are estimated to be well below the total indicative dose of 0.1 mSv/y specified in the Drinking Water Directive Groundwater used for drinking water was collected from different types of geological structures including bed rock and areas with potentially elevated levels of natural radioactivity. Also in these cases the concentrations of radioactivity were sufficiently low to meet the requirements in the Drinking Water Directive. In view of the results it seems probable that the risk of finding drinking water in Denmark with unacceptable concentrations of radioactivity is very small. Therefore there is no need for further radiological investigations of the Danish water supply based on natural groundwaters. (au)

  15. Global α -decay study based on the mass table of the relativistic continuum Hartree-Bogoliubov theory

    Science.gov (United States)

    Zhang, Lin-Feng; Xia, Xue-Wei

    2016-05-01

    The α-decay energies (Q α ) are systematically investigated with the nuclear masses for 10 ⩽ Z ⩽ 120 isotopes obtained by the relativistic continuum Hartree-Bogoliubov (RCHB) theory with the covariant density functional PC-PK1, and compared with available experimental values. It is found that the α-decay energies deduced from the RCHB results present a similar pattern to those from available experiments. Owing to the large predicted Q α values (⩾ 4 MeV), many undiscovered heavy nuclei in the proton-rich side and super-heavy nuclei may have large possibilities for α-decay. The influence of nuclear shell structure on α-decay energies is also analysed. Supported by Major State 973 Program of China (2013CB834400), National Natural Science Foundation of China (11175002, 11335002, 11375015, 11461141002), Research Fund for the Doctoral Program of Higher Education (20110001110087) and National Undergraduate Innovation Training Programs of Peking University.

  16. Temporary Personal Radioactivity

    Science.gov (United States)

    Myers, Fred

    2012-01-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances. (Contains 1 table and 2…

  17. Vibration-insensitive temperature sensing system based on fluorescence decay and using a digital processing approach

    Science.gov (United States)

    Dong, H.; Zhao, W.; Sun, T.; Grattan, K. T. V.; Al-Shamma'a, A. I.; Wei, C.; Mulrooney, J.; Clifford, J.; Fitzpatrick, C.; Lewis, E.; Degner, M.; Ewald, H.; Lochmann, S. I.; Bramann, G.; Merlone Borla, E.; Faraldi, P.; Pidria, M.

    2006-07-01

    A fluorescence-based temperature sensor system using a digital signal processing approach has been developed and evaluated in operation on a working automotive engine. The signal processing approach, using the least-squares method, makes the system relatively insensitive to intensity variations in the probe and thus provides more precise measurements when compared to a previous system designed using analogue phase-locked detection. Experiments carried out to determine the emission temperatures of a running car engine have demonstrated the effectiveness of the sensor system in monitoring exhaust temperatures up to 250 °C, and potentially higher. This paper was presented at the 13th International Conference on Sensors and Their Applications, held in Chatham, Kent, on 6-7 September 2005.

  18. Genetics of the DST-mediated mRNA decay pathway using a transgene-based selection.

    Science.gov (United States)

    Lidder, P; Johnson, M A; Sullivan, M L; Thompson, D M; Pérez-Amador, M A; Howard, C J; Green, P J

    2004-08-01

    mRNA sequences that control abundance, localization and translation initiation have been identified, yet the factors that recognize these sequences are largely unknown. In this report, a transgene-based strategy designed to isolate mutants of Arabidopsis thaliana that fail to recognize these sequences is described. In this strategy, a selectable gene and a screenable marker gene are put under the control of the sequence element being analysed and mutants are selected with altered abundance of the corresponding marker RNAs. The selection of mutants deficient in recognition of the DST (downstream) mRNA degradation signal is used as a test-case to illustrate some of the technical aspects that have facilitated success. Using this strategy, we report the isolation of a new mutant, dst3, deficient in the DST-mediated mRNA decay pathway. The targeted genetic strategy described circumvents certain technical limitations of biochemical approaches. Hence, it provides a means to investigate a variety of other mechanisms responsible for post-transcriptional regulation.

  19. Discovery potential of xenon-based neutrinoless double beta decay experiments in light of small angular scale CMB observations

    CERN Document Server

    Gomez-Cadenas, J J; Vidal, J Muñoz; Peña-Garay, C

    2013-01-01

    The South Pole Telescope (SPT) has probed an expanded angular range of the CMB temperature power spectrum. Their recent analysis of the latest cosmological data prefers nonzero neutrino masses, mnu = 0.32+-0.11 eV. This result, if confirmed by the upcoming Planck data, has deep implications on the discovery of the nature of neutrinos. In particular, the values of the effective neutrino mass involved in neutrinoless double beta decay (bb0nu) are severely constrained for both the direct and inverse hierarchy, making a discovery much more likely. In this paper, we focus in xenon-based bb0nu experiments, on the double grounds of their good performance and the suitability of the technology to large-mass scaling. We show that the current generation, with effective masses in the range of 100 kg and conceivable exposures in the range of 500 kg year, could already have a sizable opportunity to observe bb0nu events, and their combined discovery potential is quite large. The next generation, with an exposure in the rang...

  20. Investigating an organ-targeting platform based on hydroxyapatite nanoparticles using a novel in situ method of radioactive {sup 125}Iodine labeling

    Energy Technology Data Exchange (ETDEWEB)

    Ignjatović, Nenad [Centre for Fine Particles Processing and Nanotechnologies, Institute of Technical Sciences of the Serbian Academy of Science and Arts, Knez Mihailova 35/4, 11000 Belgrade (Serbia); Vranješ Djurić, Sanja [Laboratory for Radioisotopes, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001 Belgrade (Serbia); Mitić, Žarko [Faculty of Medicine, Department of Pharmacy, University of Niš, Bulevar dr Zorana Đinđića 81, 18000 Niš (Serbia); Janković, Drina [Laboratory for Radioisotopes, Vinča Institute of Nuclear Sciences, University of Belgrade, PO Box 522, 11001 Belgrade (Serbia); Uskoković, Dragan, E-mail: dragan.uskokovic@itn.sanu.ac.rs [Centre for Fine Particles Processing and Nanotechnologies, Institute of Technical Sciences of the Serbian Academy of Science and Arts, Knez Mihailova 35/4, 11000 Belgrade (Serbia)

    2014-10-01

    In this study, we have investigated the synthesis of nanoparticles of hydroxyapatite (HAp) and hydroxyapatite coated with chitosan (HAp/Ch) and the chitosan-poly-D,L-lactide-co-glycolide polymer blend (HAp/Ch-PLGA) as an organ-targeting system. We have examined and defined the final destination, as well as the dynamics and the pathways of the synthesized particles following intravenous administration in vivo. The XRD, ZP, FT-IR and SEM analyses have confirmed that the hydroxyapatite nanoparticles with d{sub 50} = 72 nm are coated with polymers. Radioactive 125-Iodine ({sup 125}I), a low energy gamma emitter, was used to develop a novel in situ method for the radiolabeling of particles and investigation of their biodistribution. {sup 125}I-labeled particles exhibited high stability in saline and serum over the second day, which justified their use in the following in vivo studies. The biodistribution of {sup 125}I-labeled particles after intravenous injection in rats differed significantly: HAp particles mostly targeted the liver, HAp/Ch the spleen and the liver, while HAp/Ch-PLGA targeted the lungs. Twenty-four hours post injection, HAp particles were excreted completely, while both {sup 125}I-HAp/Ch and {sup 125}I-HAp/Ch-PLGA were retained in the body for a prolonged period of time with more than 20% of radioactivity still found in different organs. - Highlights: • An organ-targeting carrier based on nano-hydroxyapatite • In situ labeling • Biodistribution of {sup 125}I-labeled HAp particles.

  1. Relativistic mean field description of cluster radioactivity

    Science.gov (United States)

    Bhagwat, A.; Gambhir, Y. K.

    2005-01-01

    Comprehensive investigations of the observed cluster radioactivity are carried out. First, the relativistic mean field (RMF) theory is employed for the calculations of the ground-state properties of relevant nuclei. The calculations reproduce the experiment well. The calculated RMF point densities are folded with the density-dependent M3Y nucleon-nucleon interaction to obtain the cluster-daughter interaction potential. This, along with the calculated and experimental Q values, is used in the WKB approximation for estimating the half-lives of the parent nuclei against cluster decay. The calculations qualitatively agree with the experiment. Sensitive dependence of the half-lives on Q values is explicitly demonstrated.

  2. Germanium detectors and natural radioactivity in food

    Energy Technology Data Exchange (ETDEWEB)

    Garbini, Lucia [Max-Planck-Institut fuer Physik, Muenchen (Germany); Collaboration: GeDet-Collaboration

    2013-07-01

    Potassium is a very important mineral for many physiological processes, like fluid balance, protein synthesis and signal transmission in nerves. Many aliments like raisins, bananas or chocolate contain potassium. Natural potassium contains 0.012% of the radioactive isotope Potassium 40. This isotope decays via β{sup +} decay into a metastable state of Argon 40, which reaches its ground state emitting a gamma of 1460 keV. A commercially produced Germanium detector has been used to measure the energy spectra of different selected food samples. It was calibrated with KCl and potassium contents were extracted. Results verify the high potassium content of commonly recommended food samples. However, the measurement quantitatively differ from the expectations in several cases. One of the most interesting results concerns chocolate bars with different percentages of cacao.

  3. A statistical survey of reconnection exhausts in the solar wind based on the Riemannian decay of current sheets

    Science.gov (United States)

    Sasunov, Yu. L.; Semenov, V. S.; Heyn, M. F.; Erkaev, N. V.; Kubyshkin, I. V.; Slivka, K. Yu.; Korovinskiy, D. B.; Khodachenko, M. L.

    2015-10-01

    We present a statistical study of the magnetic reconnection exhausts in solar wind. Observational data are compared with the analytical model based on the Riemann analysis of tangential discontinuity decay forced by finite X-line reconnection of skewed magnetic fields. Statistical analysis is based on 51 events of the solar wind reconnection listed in Phan et al. (2009). The best agreement of the observed and analytically predicted values is achieved for the rotational angle of the tangential magnetic field component with correlation coefficient reaching the value of 0.97. The lowest correlation coefficient of 0.87 is obtained for the exhaust flow plasma temperature. It is found that proton temperature increases at the exhaust boundary while electron temperature stays unchanged. This may indicate that heating and acceleration processes operate on the proton scale. Exhaust boundaries are identified as tangential discontinuities, except one particular event, where Alfvén discontinuity and slow shock were detected instead. Hence, the impulsive reconnection may be supposed in that case rather than steady state one. Exhaust regions extending up to 690RE, registered in some observations, do not necessarily imply X-lines of similar length. They could be explained alternatively by reconnection of skewed magnetic fields. The numerical modeling of the interplanetary coronal mass ejection (ICME) propagating in the solar wind reveals that the resistance force, impeding the ICME motion, may be reduced significantly (three times in our simulations) by means of the magnetic reconnection at the leading edge. Thus, reconnection may substantially increase ICME velocity and travel distance.

  4. Comparison of the Results of the Whole Core Decay Power Using the ORIGEN Code and ANS-1979 for the Uljin Unit 6

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Eun Hyun; Jeong, Hae Sun; Kim, Dong Ha [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    When a detailed tracking of the nuclide is not required-, i.e., only the whole core decay heat information is required, then the RN package is not activated and the DCH package is solely used, whereas both the RN and DCH packages are used when we need a fission product transport simulation and location information. For DCH only mode, there are four options to calculate the whole core decay heat calculation for the time after a shut-down. The first is using a summation of the decay heat data from ORIGEN-based fission product inventories for the representative BWRs and PWRs, which are scaled if necessary. The second is using the ANS-1979 standard for the decay heat power. The third is using a user-specified tabular function of the whole-core decay as a function of time. The fourth is using a user-specified control function to define the decay heat. In this research, for option 2, the ANS-1979 standard for the whole core decay heat calculation is compared with the result of the ORIGEN calculation for Uljin Unit 6 after arranging the ORIGEN result based on the mass, radioactivity, and decay heat for the elements and nuclides. The MELCOR code is currently using the ANS-1979 standard, the lasted version for decay heat in ANS standards is not mainly dealt with in this research. The goal of the examination is to find the necessity of changing old standard for the enhancement of the accuracy. The ANS-1979 is an old standard about decay heat, thus recent standards which are ANSI/ANS-5.1-1994 and ANSI/ANS-5.1-2005 should be investigated in the long term research. This research has certain drawback in that the mere multiplication of the number of assemblies is done for the whole core decay heat calculation in the arrangement of the ORIGEN result.

  5. Radioactivity computation of steady-state and pulsed fusion reactors operation

    Energy Technology Data Exchange (ETDEWEB)

    Attaya, H.

    1994-11-01

    The International Thermonuclear Report (ITER) is expected to operate in a pulsed operational mode. Accurate radioactivity calculations, that take into account this mode of operation, are required in order to determine precisely the different safety aspects of ITER. The authors previous examined analytically the effect of pulsed operation in ITER and showed how it depends on the burn time, the dwell time, and the half-lives. That analysis showed also that for ITER`s low duty factor, using the continuous operation assumption would considerably overestimate the radioactivities, for a wide range of half-lives. At the same time, the large improvements in the quality and the quantity of the decay and the cross-section data libraries has considerably increased the computation times of the radioactivity calculations. For both reasons it is imperative to seek different methods of solution that reduce the computational time and can be easily adopted to the treatment of the pulsed operation. In this work, they have developed algorithms based on several mathematical methods that were chosen based on their generality, reliability, stability, accuracy, and efficiency. These methods are the matrix Schuer decomposition, the eigenvector decomposition, and the Pade approximation for the matrix exponential functions.

  6. Estimation of radioactive contamination of soils from the "Balapan" and the "Experimental field" technical areas of the Semipalatinsk nuclear test site.

    Science.gov (United States)

    Evseeva, T; Belykh, E; Geras'kin, S; Majstrenko, T

    2012-07-01

    In spite of the long history of the research, radioactive contamination of the Semipalatinsk nuclear test site (SNTS) in the Republic of Kazakhstan has not been adequately characterized. Our cartographic investigation has demonstrated highly variable radioactive contamination of the SNTS. The Cs-137, Sr-90, Eu-152, Eu-154, Co-60, and Am-241 activity concentrations in soil samples from the "Balapan" site were 42.6-17646, 96-18250, 1.05-11222, 0.6-4865, 0.23-4893, and 1.2-1037 Bq kg(-1), correspondingly. Cs-137 and Sr-90 activity concentrations in soil samples from the "Experimental field" site were varied from 87 up to 400 and from 94 up to 1000 Bq kg(-1), respectively. Activity concentrations of Co-60, Eu-152, and Eu-154 were lower than the minimum detectable activity of the method used. Concentrations of naturally occurring radionuclides (K-40, Ra-226, U-238, and Th-232) in the majority of soil samples from the "Balapan" and the "Experimental field" sites did not exceed typical for surrounding of the SNTS areas levels. Estimation of risks associated with radioactive contamination based on the IAEA clearance levels for a number of key radionuclides in solid materials shows that soils sampled from the "Balapan" and the "Experimental field" sites might be considered as radioactive wastes. Decrease in specific activity of soil from the sites studied up to safety levels due to Co-60, Cs-137, Sr-90, Eu-152, Eu-154 radioactive decay and Am-241 accumulation-decay will occur not earlier than 100 years. In contrast, soils from the "Experimental field" and the "Balapan" sites (except 0.5-2.5 km distance from the "Chagan" explosion point) cannot be regarded as the radioactive wastes according safety norms valid in Russia and Kazakhstan.

  7. Accelerated radioactive beams from REX-ISOLDE

    Energy Technology Data Exchange (ETDEWEB)

    Kester, O. E-mail: oliver.kester@physik.uni-muenchen.de; Sieber, T.; Emhofer, S.; Ames, F.; Reisinger, K.; Reiter, P.; Thirolf, P.G.; Lutter, R.; Habs, D.; Wolf, B.H.; Huber, G.; Schmidt, P.; Ostrowski, A.N.; Hahn, R. von; Repnow, R.; Fitting, J.; Lauer, M.; Scheit, H.; Schwalm, D.; Podlech, H.; Schempp, A.; Ratzinger, U.; Forstner, O.; Wenander, F.; Cederkaell, J.; Nilsson, T.; Lindroos, M.; Fynbo, H.; Franchoo, S.; Bergmann, U.; Oinonen, M.; Aeystoe, J.; Den Bergh, P. Van; Duppen, P. Van; Huyse, M.; Warr, N.; Weisshaar, D.; Eberth, J.; Jonson, B.; Nyman, G.; Pantea, M.; Simon, H.; Shrieder, G.; Richter, A.; Tengblad, O.; Davinson, T.; Woods, P.J.; Bollen, G.; Weissmann, L.; Liljeby, L.; Rensfelt, K.G

    2003-05-01

    In 2001 the linear accelerator of the Radioactive beam EXperiment (REX-ISOLDE) delivered for the first time accelerated radioactive ion beams, at a beam energy of 2 MeV/u. REX-ISOLDE uses the method of charge-state breeding, in order to enhance the charge state of the ions before injection into the LINAC. Radioactive singly-charged ions from the on-line mass separator ISOLDE are first accumulated in a Penning trap, then charge bred to an A/q<4.5 in an electron beam ion source (EBIS) and finally accelerated in a LINAC from 5 keV/u to energies between 0.8 and 2.2 MeV/u. Dedicated measurements with REXTRAP, the transfer line and the EBIS have been carried out in conjunction with the first commissioning of the accelerator. Thus the properties of the different elements could be determined for further optimization of the system. In two test beam times in 2001 stable and radioactive Na isotopes ({sup 23}Na-{sup 26}Na) have been accelerated and transmitted to a preliminary target station. There {sup 58}Ni- and {sup 9}Be- and {sup 2}H-targets have been used to study exited states via Coulomb excitation and neutron transfer reactions. One MINIBALL triple cluster detector was used together with a double sided silicon strip detector to detect scattered particles in coincidence with {gamma}-rays. The aim was to study the operation of the detector under realistic conditions with {gamma}-background from the {beta}-decay of the radioactive ions and from the cavities. Recently for efficient detection eight tripple Ge-detectors of MINIBALL and a double sided silicon strip detector have been installed. We will present the first results obtained in the commissioning experiments and will give an overview of realistic beam parameters for future experiments to be started in the spring 2002.

  8. An inter-comparison of sediment classification methods based on multi-beam echo-sounder backscatter and sediment natural radioactivity data.

    Science.gov (United States)

    Snellen, Mirjam; Eleftherakis, Dimitrios; Amiri-Simkooei, Alireza; Koomans, Ronald L; Simons, Dick G

    2013-08-01

    This contribution presents sediment classification results derived from different sources of data collected at the Dordtse Kil river, the Netherlands. The first source is a multi-beam echo-sounder (MBES). The second source is measurements taken with a gamma-ray scintillation detector, i.e., the Multi-Element Detection System for Underwater Sediment Activity (Medusa), towed over the sediments and measuring sediment natural radioactivity. Two analysis methods are employed for sediment classification based on the MBES data. The first is a Bayesian estimation method that uses the average backscatter data per beam and, therefore, is independent of the quality of the MBES calibration. The second is a model-based method that matches the measured backscatter curves to theoretical curves, predicted by a physics-based model. Medusa provides estimates for the concentrations of potassium, uranium, thorium, and cesium, known to be indicative for sediment properties, viz. mean grain size, silt content, and the presence of organic matter. In addition, a hydrophone attached to the Medusa system provides information regarding the sediment roughness. This paper presents an inter-comparison between the sediment classification results using the above-mentioned methods. It is shown that although originating from completely different sources, the MBES and Medusa provide similar information, revealing the same sediment distribution.

  9. Evaluating airborne and ground based gamma spectrometry methods for detecting particulate radioactivity in the environment: A case study of Irish Sea beaches

    Energy Technology Data Exchange (ETDEWEB)

    Cresswell, A.J., E-mail: Alan.Cresswell@glasgow.ac.uk; Sanderson, D.C.W.

    2012-10-15

    In several places, programmes are in place to locate and recover radioactive particles that have the potential to cause detrimental health effects in any member of the public who may encounter them. A model has been developed to evaluate the use of mobile gamma spectrometry systems within such programmes, with particular emphasis on large volume (16 l) NaI(Tl) detectors mounted in low flying helicopters. This model uses a validated Monte Carlo code with assessment of local geochemistry and natural and anthropogenic background radiation concentrations and distributions. The results of the model, applied to the example of particles recovered from beaches in the vicinity of Sellafield, clearly show the ability of rapid airborne surveys conducted at 75 m ground clearance and 120 kph speeds to demonstrate the absence of sources greater than 5 MBq {sup 137}Cs within large areas (10-20 km{sup 2} h{sup -1}), and identify areas requiring further ground based investigation. Lowering ground clearance for airborne surveys to 15 m whilst maintaining speeds covering 1-2 km{sup 2} h{sup -1} can detect buried {sup 137}Cs sources of 0.5 MBq or greater activity. A survey design to detect 100 kBq {sup 137}Cs sources at 10 cm depth has also been defined, requiring surveys at < 15 m ground clearance and < 2 m s{sup -1} ground speed. The response of airborne systems to the Sellafield particles recovered to date has also been simulated, and the proportion of the existing radiocaesium background in the vicinity of the nuclear site has been established. Finally the rates of area coverage and sensitivities of both airborne and ground based approaches are compared, demonstrating the ability of airborne systems to increase the rate of particle recovery in a cost effective manner. The potential for equipment and methodological developments to improve performance are discussed. -- Highlights: Black-Right-Pointing-Pointer Validated Monte Carlo simulations used to model mobile gamma spectrometry

  10. Evil radioactivity. Subjective perception of radioactivity in patients with thyroid disease prior to treatment with radioiodine

    Energy Technology Data Exchange (ETDEWEB)

    Freudenberg, L.S. [Universitaetsklinikum Essen (Germany). Klinik fuer Nuklearmedizin; Radiologisch-Nuklearmedizinische Gemeinschaftspraxis, Grevenbroich (Germany); Beyer, T.; Mueller, S.P.; Goerges, R.; Bockisch, A. [Universitaetsklinikum Essen (Germany). Klinik fuer Nuklearmedizin; Hopfenbach, A. [Radiologisch-Nuklearmedizinische Gemeinschaftspraxis, Grevenbroich (Germany)

    2006-07-01

    Aim: We assess the perspective of patients with thyroid disease towards radiation and radioactivity by means of a cultural-anthropological approach based on qualitative measures and quantitative scores. From the interviews with the patients we evaluate as to how much radioactivity is accepted as an abstract term or as a benefit within the medical context. Patients, methods: 68 patients with autonomously functioning thyroid lesions (35 women, 33 men, 32-81 years) were included in this study. All patients were interviewed in an open dialogue with the principal investigator. Patients were asked to describe their attitude towards radioactivity in general and towards radioiodine therapy in particular. Patients were asked to use a scoring system (1=positive, 5=negative) to quantify their attitudes. Results: The responses of all patients towards radioactivity in general were heterogeneous with most responses reflecting a negative perception. Many patients expressed their associated fears about atomic energy, malignant diseases and radioactive contamination. The scoring system reflected a mostly negative opinion base. However, patients became more positive once they assumed an immediate benefit of radioactivity for the treatment of their own disease (p=0.01). Conclusions: Knowing about significant differences in patient's perception about radioactivity in general or in the clinical context may help to optimise and tailor the initial, pre-therapeutical interview towards the patient. (orig.)

  11. The X-Array and SATURN: A new decay-spectroscopy station for CARIBU

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, A.J., E-mail: alan_mitchell@uml.edu [Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854 (United States); Bertone, P.F.; DiGiovine, B. [Physics Division, Argonne National Laboratory, Argonne, Il 60439 (United States); Lister, C.J. [Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854 (United States); Carpenter, M.P. [Physics Division, Argonne National Laboratory, Argonne, Il 60439 (United States); Chowdhury, P. [Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854 (United States); Clark, J.A. [Physics Division, Argonne National Laboratory, Argonne, Il 60439 (United States); D' Olympia, N.; Deo, A.Y. [Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854 (United States); Kondev, F.G. [Physics Division, Argonne National Laboratory, Argonne, Il 60439 (United States); Nuclear Engineering Division, Argonne National Laboratory, Argonne, Il 60439 (United States); McCutchan, E.A.; Rohrer, J. [Physics Division, Argonne National Laboratory, Argonne, Il 60439 (United States); Savard, G. [Physics Division, Argonne National Laboratory, Argonne, Il 60439 (United States); Department of Physics, University of Chicago, Chicago, Il 60637 (United States); Seweryniak, D.; Zhu, S. [Physics Division, Argonne National Laboratory, Argonne, Il 60439 (United States)

    2014-11-01

    A new decay-spectroscopy station has been commissioned for experiments with low-energy, fission-fragment radioactive beams from the CARIBU ion source. The new set-up consists of the ‘X-Array’, a highly-efficient array of HPGe clover detectors, and ‘SATURN’ (Scintillator And Tape Using Radioactive Nuclei), a plastic scintillator detector combined with a tape-transport system for detection of β particles and removal of long-lived isobaric decay products.

  12. The X-Array and SATURN: A new decay-spectroscopy station for CARIBU

    CERN Document Server

    Mitchell, A J; DiGiovine, B; Lister, C J; Carpenter, M P; Chowdhury, P; Clark, J A; D'Olympia, N; Deo, A Y; Kondev, F G; McCutchan, E A; Rohrer, J; Savard, G; Seweryniak, D; Zhu, S

    2015-01-01

    A new decay-spectroscopy station has been commissioned for experiments with low-energy, fission-fragment radioactive beams from the CARIBU ion source. The new set-up consists of the 'X-array', a highly-efficient array of HPGe clover detectors, and 'SATURN' (Scintillator And Tape Using Radioactive Nuclei), a plastic scintillator detector combined with a tape-transport system for detection of beta particles and removal of long-lived isobaric decay products.

  13. Discovery potential of xenon-based neutrinoless double beta decay experiments in light of small angular scale CMB observations

    Energy Technology Data Exchange (ETDEWEB)

    Gómez-Cadenas, J.J.; Martín-Albo, J.; Vidal, J. Muñoz; Peña-Garay, C., E-mail: gomez@mail.cern.ch, E-mail: jmalbos@ific.uv.es, E-mail: jmunoz@ific.uv.es, E-mail: penya@ific.uv.es [Instituto de Física Corpuscular (IFIC), CSIC and Universitat de Valencia Calle Catedrático José Beltrán, 2, 46090 Paterna, Valencia (Spain)

    2013-03-01

    The South Pole Telescope (SPT) has probed an expanded angular range of the CMB temperature power spectrum. Their recent analysis of the latest cosmological data prefers nonzero neutrino masses, with Σm{sub ν} = (0.32±0.11) eV. This result, if confirmed by the upcoming Planck data, has deep implications on the discovery of the nature of neutrinos. In particular, the values of the effective neutrino mass m{sub ββ} involved in neutrinoless double beta decay (ββ0ν) are severely constrained for both the direct and inverse hierarchy, making a discovery much more likely. In this paper, we focus in xenon-based ββ0ν experiments, on the double grounds of their good performance and the suitability of the technology to large-mass scaling. We show that the current generation, with effective masses in the range of 100 kg and conceivable exposures in the range of 500 kg·year, could already have a sizeable opportunity to observe ββ0ν events, and their combined discovery potential is quite large. The next generation, with an exposure in the range of 10 ton·year, would have a much more enhanced sensitivity, in particular due to the very low specific background that all the xenon technologies (liquid xenon, high-pressure xenon and xenon dissolved in liquid scintillator) can achieve. In addition, a high-pressure xenon gas TPC also features superb energy resolution. We show that such detector can fully explore the range of allowed effective Majorana masses, thus making a discovery very likely.

  14. Decays of s neutrinos

    CERN Document Server

    Barradas, J E

    2003-01-01

    Based on the Minimal Supersymmetric Standard Model (MSSM), we discussed possible two body decay modes for the s neutrino v, one charged and other neutral: v -> l sub x sub 1 sup + sup - and v -> vx sub 1 sup 0 , respectively. Exploring a range of possible values for its mass, and for the chargino x sub i sup + sup - and neutralino x sub j sup 0 masses as well. We present the specific calculation for branching ratios, which are analyzed numerically. (Author)

  15. Atomic nuclei decay modes by spontaneous emission of heavy ions

    OpenAIRE

    Poenaru, Dorin N.; Ivaşcu, Marin; Săndulescu, Aurel; Greiner, Walter

    2006-01-01

    The great majority of the known nuclides with Z>40, including the so-called stable nuclides, are metastable with respect to several modes of spontaneous superasymmetric splitting. A model extended from the fission theory of alpha decay allows one to estimate the lifetimes and the branching ratios relative to the alpha decay for these natural radioactivities. From a huge amount of systematic calculations it is concluded that the process should proceed with maximum intensity in the trans-lead n...

  16. Simulation of decays and secondary ion losses in a betabeam decay ring

    CERN Document Server

    Jones, F.W.; 10.1109/PAC.2007.4440382

    Radioactive ions injected into the decay ring of aBetabeam neutrino facility will constitute a continuoussource of decay products distributed around the ring.Secondary ions from beta decays will differ in chargestate from the primary ions and will follow widely offmomentumorbits. In the racetrack configuration of thering, they will be mismatched in the long straights and mayacquire large amplitudes, but the great majority of losseswill be in the arcs. We describe here a comprehensivemodel of ion decay, secondary ion tracking, and loss detection,which has been implemented in the tracking andsimulation code Accsim. Methods have been developed toaccurately follow ion trajectories at large momentum deviationsas well as to detect their impact coordinates on vacuumchamber walls and possibly inside magnetic elements.Using secondary-ion data from Accsim and postprocessingwith Mathematica, we have implemented afollow-on simulation in FLUKA with a 3D geometry ofdecay ring components and physics models for ion interacti...

  17. RESRAD. Site-Specific Residual Radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Yu, C. [Argonne National Laboratory, IL (United States)

    1989-06-01

    RESRAD is designed to derive site-specific guidelines for allowable residual concentrations of radionuclides in soil. A guideline is defined as a radionuclide concentration or a level of radiation or radioactivity that is acceptable if a site is to be used without radiological restrictions. Guidelines are expressed as (1) concentrations of residual radionuclides in soil, (2) concentrations of airborne radon decay products, (3) levels of external gamma radiation, (4) levels of radioactivity from surface contamination, and (5) concentrations of residual radionuclides in air and water. Soil is defined as unconsolidated earth material, including rubble and debris that may be present. The controlling principles of all guidelines are (1) the annual radiation dose received by a member of the critical population group from the residual radioactive material - predicted by a realistic but reasonably conservative analysis and averaged over a 50 year period - should not exceed 100 mrem/yr, and (2) doses should be kept as low as reasonably achievable. All significant exposure pathways for the critical population group are considered in deriving soil guidelines. These pathways include direct exposure to external radiation from the contaminated soil material; internal radiation from inhalation of airborne radionuclides; and internal radiation from ingestion of plant foods grown in the contaminated soil, meat and milk from livestock fed with contaminated fodder and water, drinking water from a contaminated well, and fish from a contaminated pond.

  18. Nonleptonic Bc→VV decays

    Science.gov (United States)

    Kar, Susmita; Dash, P. C.; Priyadarsini, M.; Naimuddin, Sk.; Barik, N.

    2013-11-01

    We study the exclusive nonleptonic Bc→VV decays, within the factorization approximation, in the framework of the relativistic independent quark model, based on a confining potential in the scalar-vector harmonic form. The weak form factors are extracted from the overlap integral of meson wave functions derived in the relativistic independent quark model. The predicted branching ratios for different Bc-meson decays are obtained in a wide range, from a tiny value of O(10-6) for Bc→D*D(s)* to a large value of 24.32% for Bc→Bs*ρ-, in general agreement with other dynamical-quark-model predictions. The decay modes Bc→Bs*ρ- and Bc→B*ρ- with high branching ratios of 24.32% and 1.73%, respectively, obtained in this model should be detectable at the LHC and Tevatron in the near future. The b→c, u induced decays are predicted predominantly in the longitudinal mode, whereas the c¯→s¯, d¯ induced decays are obtained in a slightly higher transverse mode. The CP-odd fractions (R⊥) for different decay modes are predicted and those for color-favored Bc→D*D*, D*Ds* decays indicate significant CP violation in this sector.

  19. $D$ leptonic and semileptonic decays

    CERN Document Server

    Ma, Hailong

    2015-01-01

    Based on 2.92 fb$^{-1}$ data taken at the center-of-mass energy $\\sqrt s=3.773$ GeV with the BESIII detector, we report recent results on the decay constant $f_{D^+}$, the hadronic form factors, as well as the quark mixing matrix elements $|V_{cs(d)}|$, which are extracted from analyses of the leptonic decay $D^+ \\to \\mu^+\

  20. Three-body charmless B decays workshop

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Haim, E.; Chauveau, J.; Hartfiel, B.; Ocariz, J. [Laboratoire de Physique Nucleaire et de Hautes Energies (LPNHE), 75 - Paris (France); Charles, J. [LPT, 13 - Marseille (France)

    2006-07-01

    The purpose of this workshop was multifarious: -) to present and discuss the current experimental perspectives based on the full expected statistics from B-factories by 2008, -) to share and further develop analysis methods, -) to present and discuss the theoretical work on the subject, -) to discuss the future of B-factories, and -) to establish a work plan until 2009. The contributions have focused on 3 body charmless B decays and mostly 3 body hadronic charmless B decays, they have also dealt with semileptonic decays, radiative decays, charm and charmonium decays, and scattering processes. This document gathers the slides of the presentations.

  1. Radioactivity: A Natural Phenomenon.

    Science.gov (United States)

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  2. Viewer Makes Radioactivity "Visible"

    Science.gov (United States)

    Yin, L. I.

    1983-01-01

    Battery operated viewer demonstrates feasibility of generating threedimensional visible light simulations of objects that emit X-ray or gamma rays. Ray paths are traced for two pinhold positions to show location of reconstructed image. Images formed by pinholes are converted to intensified visible-light images. Applications range from radioactivity contamination surveys to monitoring radioisotope absorption in tumors.

  3. AIR RADIOACTIVITY MONITOR

    Science.gov (United States)

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  4. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate and massive objects require a longer procedure and will therefore take longer.

  5. Radioactive Sources Service

    CERN Multimedia

    2007-01-01

    Please note that the radioactive sources service will be open by appointment only every Monday, Wednesday and Friday during CERN working hours (instead of alternate weeks). In addition, please note that our 2007 schedule is available on our web site: http://cern.ch/service-rp-sources

  6. Radioactive Sources Service

    CERN Multimedia

    2007-01-01

    Please note that the radioactive sources service will be open by appointment only every Monday, Wednesday and Friday during CERN working hours (instead of alternate weeks). In addition, please note that our 2007 schedule is available on our web site. http://cern.ch/service-rp-sources

  7. Survey monitoring of environmental radioactivity in Jeju area

    Energy Technology Data Exchange (ETDEWEB)

    U, Zang Kual; Kang, Tae Woo; Park, Won Pyo [Jeju National Univ., Jeju (Korea, Republic of)

    2003-12-15

    The project is carried out to monitor the change of environmental radioactivity in Jeju, and to provide a systematic data for radiation monitoring and counter measurement at a radiological emergency situation. Also the survey of natural environmental radioactivities in the samples was conducted to make the reliable data base for evaluation of internal exposure and environmental contamination of radiation. This report contains the data of gamma exposure rates and radioactivities of airborne dust, fallout, precipitation and tap water which were analyzed periodically by Jeju Regional Monitoring Station in 2002. Also it contains the data of natural radioactivity levels of food stuff such as agricultural and marine products, including drinking waters.

  8. Optimum orientation versus orientation averaging description of cluster radioactivity

    CERN Document Server

    Seif, W M; Refaie, A I; Amer, L H

    2016-01-01

    Background: The deformation of the nuclei involved in the cluster decay of heavy nuclei affect seriously their half-lives against the decay. Purpose: We investigate the description of the different decay stages in both the optimum orientation and the orientation-averaged pictures of the cluster decay process. Method: We consider the decays of 232,233,234U and 236,238Pu isotopes. The quantum mechanical knocking frequency and penetration probability based on the Wentzel-Kramers-Brillouin approximation are used to find the decay width. Results: We found that the orientation-averaged decay width is one or two orders of magnitude less than its value along the non-compact optimum orientation. The difference between the two values increases with decreasing the mass number of the emitted cluster. Correspondingly, the extracted preformation probability based on the averaged decay width increases with the same orders of magnitude compared to its value obtained considering the optimum orientation. The cluster preformati...

  9. GEMS: Underwater spectrometer for long-term radioactivity measurements

    OpenAIRE

    2010-01-01

    GEMS (Gamma Energy Marine Spectrometer) is a prototype of an autonomous radioactivity sensor for underwater measurements, developed in the framework of the KM3NeT Design Study (DS) EC project. The spectrometer is sensitive to gamma rays produced by 40K decays and it is also able to detect other natural (e.g., 238U, 232Th) and anthropogenic radionuclides (e.g. 137Cs). The decay of 40K, contained in sea salt, particulate and sediments, is one of the main sources of photon background...

  10. Optimisation of the Hadronic Tau Identification Based on the Classification of Tau Decay Modes with the ATLAS Detector

    CERN Document Server

    Hanisch, Stefanie; Siegert, Frank

    Hadronically decaying tau leptons play an essential role in the LHC physics program. Final states involving tau leptons are important to verify processes of the Standard Model of particle physics at the TeV scale, but are also of high interest for Higgs physics and beyond Standard Model studies, like Higgs CP measurements and $A\\to Zh$ searches. Due to the high production cross section of QCD jets which are the dominant background, efficient reconstruction and identification techniques are crucial to guarantee an excellent selection of interesting physics events. Therefore, sophisticated multivariate algorithms are used. This thesis presents an advanced concept exploiting the information of reconstructed neutral and charged pions in the ATLAS detector, to access the tau decay substructure, and thus enhance the applicability of the tau identification to a broader field of physics analyses. First, several updates of the general algorithms used within the tau identification are implemented in order to provide...

  11. Bases for an environmental liability management system: application to a repository for radioactive waste; Bases para um sistema de gerenciamento de responsabilidades ambientais: aplicacao a um repositorio de rejeitos radioativos

    Energy Technology Data Exchange (ETDEWEB)

    Tostes, Marcelo Mallat

    1999-03-15

    This thesis aims the establishment of conceptual bases for the development of Environmental Liability Management System - instruments designed to provide financial and managerial coverage to financial liabilities arising from activities that impact the environment. The document analyses the theories that link the evolution of economic thought and environment, as a means of establish the necessary framework for the development of up-to-date environmental policy instruments. From these concepts and from the analysis of environmental liability system being implemented in several countries, the bases for environmental liability systems development are drawn. Finally, a study is carried out on the application of these bases for the development of an environmental liability management system for a radioactive waste repository. (author)

  12. Design of intelligent security system for radioactive material based on Zigbee technology%基于 Zigbee 技术放射性物质智能安保系统设计

    Institute of Scientific and Technical Information of China (English)

    王长清; 曹渊

    2016-01-01

    For research and use of radioactive material in an urban environment , the radioactive material can't make the right response on accidents such as illegal movement , theft and leakage in time , which appeared in the process of the storage , and the regulation technology can't achieve real-time dynamic monitoring of radioactive materials .This paper proposes a wireless intelligent remote security system based on ZigBee technology , with different peripheral sen-sors to complete intelligent monitoring of radioactive materials , and the signal strength indicator value is used to deter-mine the storage safety of radioactive substances .The experimental results show that the system has stable perform-ance, high sensitivity , and broad application prospects .%针对在城市环境中对放射性物质研究与使用时,放射性物质在存储过程中出现的非法移动、偷盗和泄露等事故时不能及时做出正确的响应,且放射性物质的监管技术不能实现实时动态监控,提出了一种基于Zigbee技术的无线智能远程安保系统的设计方案,借助不同性能的外设传感器完成对放射性物质的智能监控,采用信号强度指示值完成对放射性物质存储安全的确定。实验结果表明,本系统性能稳定,灵敏度高,具有广阔的应用前景。

  13. Long-Term Stability of Underground Operated CZT Detectors Based on the Analysis of Intrinsic $^{113}$Cd \\beta$^{-}$-Decay

    CERN Document Server

    Ebert, J; Gehre, D; Hagner, C; Heidrich, N; Klingenberg, R; Kroeninger, K; Nitsch, C; Oldorf, C; Quante, T; Rajek, S; Rebber, H; Rohatsch, K; Tebruegge, J; Temminghoff, R; Theinert, R; Timm, J; Wonsak, B; Zatschler, S; Zuber, K

    2015-01-01

    The COBRA collaboration operates a demonstrator setup at the underground facility LNGS (Laboratori Nazionali del Gran Sasso, located in Italy) to prove the technological capabilities of this concept for the search for neutrinoless double beta-decay. The setup consists of 64 $(1\\times\\!1\\times\\!1)$ cm$^{3}$ CZT detectors in CPG configuration. One purpose of this demonstrator is to test if reliable long-term operation of CZT-CPG detectors in such a setup is possible. The demonstrator has been operated under ultra low-background conditions since more than three years and collected data corresponding to an exposure of 218 kg$\\cdot$days. The presented study focuses on the long-term stability of CZT detectors by analyzing the intrinsic, fourfold forbidden non-unique $^{113}$Cd single beta-decay. It can be shown that CZT detectors can be operated stably for long periods of time and that the $^{113}$Cd single beta-decay can be used as an internal monitor of the detector performance during the runtime of the experimen...

  14. CP-Violation in Neutrino Oscillations from EC/{beta}{sup +} decaying ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza, Catalina [Centre for Theoretical Particle Physics, IST, Technical University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal)

    2012-08-15

    We discuss the separation of unknown neutrino properties by means of the energy dependence of the oscillation probability and we consider an hybrid setup which combines the electron capture and the {beta}{sup +} decay from the same radioactive proton-rich ion with the same boost. We conclude that the combination of the two decay channels, with different neutrino energies, achieves remarkable results.

  15. NEW GAMMA RAYS FROM DECAY OF 189W

    Institute of Scientific and Technical Information of China (English)

    杨维凡; 赵之正; 等

    1995-01-01

    Radioactivities of 189W are produced through an 192Os(n,α189W reaction.Gamma ray spectroscopy from chemically separated tungsten sources using HPGe detector has revealed the presence of 22 gamma rays assigned to the decay of 189W,of them,18 gamma rays are new ones unreported until now.

  16. Radioactive waste management; Gerencia de rejeitos radioativos

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-11-15

    This eighth chapter presents the radioactive wastes and waste disposal; classification of radioactive wastes; basis requests of the radioactive waste management; conditions for a radioactive waste disposal; registers and inventories; transport of radioactive wastes from a facility to another and the radioactive waste management plan.

  17. Transport and extraction of radioactive ions stopped in superfluid helium

    CERN Document Server

    Huang Wan Xia; Gloos, K; Takahashi, N; Arutyunov, K; Pekola, J P; Äystö, J

    2003-01-01

    A new approach to convert a high energy beam to a low energy one, which is essential for the next generation radioactive ion beam facilities, has been proposed and tested at Jyvaeskylae, Finland. An open sup 2 sup 2 sup 3 Ra alpha-decay-recoil source has been used to produce radioactive ions in superfluid helium. The alpha spectra demonstrate that the recoiling sup 2 sup 1 sup 9 Rn ions have been extracted out of liquid helium. This first observation of the extraction of heavy positive ions across the superfluid helium surface was possible thanks to the high sensitivity of radioactivity detection. An efficiency of 36% was obtained for the ion extraction out of liquid helium.

  18. LRT 2006: 2. topical workshop in low radioactivity techniques

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, P.; Piquemal, F.; Ford, R.; Yakushev, E.; Pandola, L.; Franco, D.; Bellini, F.; Hubert, Ph.; Laubenstein, M.; Abt, I.; Bongrand, M.; Schnee, R.; Dusan, B.; Chen, M.; Piquemal, F.; Nachab, A.; Zuzel, G.; Simgen, H.; Navick, X.F.; Pedretti, M.; Wojcik, M.; Sekiya, H.; Kim, Y.; Kishimoto, T.; Dawson, J.; Borjabad, S.; Perrot, F.; Gurriaran, R.; Nikolayko, A.; Hubert, Ph

    2006-07-01

    This second topical workshop in low radioactivity techniques is intended to bring together experts in the field of low background techniques, especially applied to dark matter experiments, double beta decay experiments and neutrino detection in underground laboratories. This workshop has been organized into 7 sessions: 1) underground facilities (where a worldwide review is made), 2) neutron and muon induced background, isotope production, 3) low background counting techniques and low background detectors, 4) techniques for radon reduction, purified noble gases and liquid scintillator purification, 5) low levels on Pb-Bi-Po{sup 210} and surface background, 6) low radioactivity detector components and material purification, and 7) low radioactive techniques in other applications (particularly to check the geographical origin of food-products or to date wine. This document is made up of the slides of the presentations.

  19. Characterization of defects in semiconductors using radioactive isotopes

    CERN Document Server

    Deicher, Manfred

    2007-01-01

    Radioactive atoms have been used in solid-state physics and in material science for many decades. Besides their classical application as tracer for diffusion studies, nuclear techniques such as Mossbauer spectroscopy, perturbed angular correlation, and emission channeling have used nuclear properties to gain microscopical information on the structural and dynamical properties of solids. The availability of many different radioactive isotopes as a clean ion beam at facilities like ISOLDE/CERN has triggered a new era involving methods sensitive for the optical and electronic properties of solids, especially in the field of semiconductor physics. Spectroscopic techniques like photoluminescence (PL), deep-level transient spectroscopy (DLTS), and Hall effect gain a new quality by using radioactive isotopes. Due to their decay the chemical origin of an observed electronic and optical behavior of a specific defect or dopant can be unambiguously identified. This contribution will highlight a few examples to illustrat...

  20. Handbook of radioactivity analysis

    CERN Document Server

    2012-01-01

    The updated and much expanded Third Edition of the "Handbook of Radioactivity Analysis" is an authoritative reference providing the principles, practical techniques, and procedures for the accurate measurement of radioactivity from the very low levels encountered in the environment to higher levels measured in radioisotope research, clinical laboratories, biological sciences, radionuclide standardization, nuclear medicine, nuclear power, fuel cycle facilities and in the implementation of nuclear forensic analysis and nuclear safeguards. The Third Edition contains seven new chapters providing a reference text much broader in scope than the previous Second Edition, and all of the other chapters have been updated and expanded many with new authors. The book describes the basic principles of radiation detection and measurement, the preparation of samples from a wide variety of matrices, assists the investigator or technician in the selection and use of appropriate radiation detectors, and presents state-of-the-ar...

  1. Alpha decay as a probe for the structure of neutron-deficient nuclei

    CERN Document Server

    Qi, Chong

    2016-01-01

    The advent of radioactive ion beam facilities and new detector technologies have opened up new possibilities to investigate the radioactive decays of highly unstable nuclei, in particular the proton emission, $\\alpha$ decay and heavy cluster decays from neutron-deficient (or proton-rich) nuclei around the proton drip line. It turns out that these decay measurements can serve as a unique probe for studying the structure of the nuclei involved. On the theoretical side, the development in nuclear many-body theories and supercomputing facilities have also made it possible to simulate the nuclear clusterization and decays from a microscopic and consistent perspective. In this article we would like to review the current status of these structure and decay studies in heavy nuclei, regarding both experimental and theoretical opportunities. We then discuss in detail the recent progress in our understanding of the nuclear $\\alpha$ formation probabilities in heavy nuclei and their indication on the underlying nuclear st...

  2. SHIPPING OF RADIOACTIVE ITEMS

    CERN Multimedia

    TIS/RP Group

    2001-01-01

    The TIS-RP group informs users that shipping of small radioactive items is normally guaranteed within 24 hours from the time the material is handed in at the TIS-RP service. This time is imposed by the necessary procedures (identification of the radionuclides, determination of dose rate, preparation of the package and related paperwork). Large and massive objects require a longer procedure and will therefore take longer.

  3. White sea radioactivity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Aliev, R.A. [Lomonosov Moscow State Univ. (Russian Federation). Skobeltsyn Inst. of Nuclear Physics]|[Lomonosov Moscow State Univ. (Russian Federation). Chemistry Dept.]|[Russian Academy of Sciences, Moscow (Russian Federation). Shirshov Inst. of Oceanology; Kalmykov, S.N.; Lisitzin, A.P. [Lomonosov Moscow State Univ. (Russian Federation). Chemistry Dept.

    2004-07-01

    The aim of the present work is to estimate potential sources and chronology of pollution of the White Sea (Russia) by artificial radionuclides. White Sea is semi-closed water body connected with Barents Sea by a narrow strait. Thus, pollution of White Sea may be caused by highly polluted Barents waters and river (mainly Northern Dvina) run-off. This is the first detailed investigation of radioactivity of White Sea sediment records. (orig.)

  4. Far Field Sorption Data Bases for Performance Assessment of a High-Level Radioactive Waste Repository in an Undisturbed Opalinus Clay Host Rock

    Energy Technology Data Exchange (ETDEWEB)

    Bradburry, M.; Baeyens, B

    2003-08-01

    An Opalinus Clay formation in the Zuercher Weinland is under consideration by Nagra as a potential location for a high-level and long-Iived intermediate-level radioactive waste repository. Performance assessment studies will be performed for this site and the purpose of this report is to describe the procedures used to develop sorption data bases appropriate for an undisturbed Opalinus Clay host rock which are required for such safety analysis calculations. In tight, low water content argillaceous rock formations such as Opalinus Clay, there is uncertainty concerning the in situ pH/P{sub CO{sub 2}}. In order to take this intrinsic uncertainty into account porewater chemistries were calculated for a reference case, pH = 7.24, and for two other pH values, 6.3 and 7.8. Sorption data bases are given for the three cases. The basis for the sorption data bases is 'in-house' sorption measurements for Cs(I), Sr(II), Ni(II), Eu(III), Sn(IV), Se(IV), Th(IV) and I(-I) carried out on Opalinus Clay samples from Mont Terri (Canton Jura) since at the time the experiments were performed no core samples from the Benken borehole (Zuercher Weinland) were available. The Opalinus Clay at Mont Terri and Benken are part of the same geological formation . Despite having directly measured data for the above key radionuclides, some of the required distribution ratios (Rd) used to generate the sorption data bases still came from the open literature. An important part of this report is concerned with describing the procedures whereby these selected literature Rd values were modified so as to apply to the Benken Opalinus Clay mineralogy and groundwater chemistries calculated at the three pH values given above. The resulting Rd values were then further modified using so-called Lab{yields}Field transfer factors to produce sorption values which were appropriate to the in situ bulk rock for the selected range of water chemistry conditions. Finally, it is important to have some

  5. Benchmark calculation for radioactivity inventory using MAXS library based on JENDL-4.0 and JEFF-3.0/A for decommissioning BWR plants

    Directory of Open Access Journals (Sweden)

    Tanaka Ken-ichi

    2016-01-01

    Full Text Available We performed benchmark calculation for radioactivity activated in a Primary Containment Vessel (PCV of a Boiling Water Reactor (BWR by using MAXS library, which was developed by collapsing with neutron energy spectra in the PCV of the BWR. Radioactivities due to neutron irradiation were measured by using activation foil detector of Gold (Au and Nickel (Ni at thirty locations in the PCV. We performed activation calculations of the foils with SCALE5.1/ORIGEN-S code with irradiation conditions of each foil location as the benchmark calculation. We compared calculations and measurements to estimate an effectiveness of MAXS library.

  6. Radioactive waste storage issues

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, Daniel E. [Colorado Christian Univ., Lakewood, CO (United States)

    1994-08-15

    In the United States we generate greater than 500 million tons of toxic waste per year which pose a threat to human health and the environment. Some of the most toxic of these wastes are those that are radioactively contaminated. This thesis explores the need for permanent disposal facilities to isolate radioactive waste materials that are being stored temporarily, and therefore potentially unsafely, at generating facilities. Because of current controversies involving the interstate transfer of toxic waste, more states are restricting the flow of wastes into - their borders with the resultant outcome of requiring the management (storage and disposal) of wastes generated solely within a state`s boundary to remain there. The purpose of this project is to study nuclear waste storage issues and public perceptions of this important matter. Temporary storage at generating facilities is a cause for safety concerns and underscores, the need for the opening of permanent disposal sites. Political controversies and public concern are forcing states to look within their own borders to find solutions to this difficult problem. Permanent disposal or retrievable storage for radioactive waste may become a necessity in the near future in Colorado. Suitable areas that could support - a nuclear storage/disposal site need to be explored to make certain the health, safety and environment of our citizens now, and that of future generations, will be protected.

  7. Environmental radioactivity survey in Andong area

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Zi Hong; Jo, Kum Ju [Andong Regional Radioactivity Monitoring Station, Andong National Univ., Andong (Korea, Republic of)

    2001-12-15

    The objectives of the project are to monitor an abnormal level in Andong area and to provide a base-line data on environmental radiation/radioactivity levels in case of any radiological emergency situation. The project is important in view of protecting the public health from the potential hazards of radiation and keeping up the clean environment. This report summarizes and interprets environmental radiation/radioactivity monitoring samples Gamma exposure rates, airborne dust, precipitation, fall-out and drinking-water. Environmental samples : vegetables, fishes/shellfishes, fruits, starch and starch roots and drinking waters. Among the all 2001 radiological monitoring and environmental data in Andong area were not found the extraordinary data. And a nation-wide environmental radiation/radioactivity level survey results were all background levels attributed to terrestrial and cosmic radiation.

  8. ANNUAL RADIOACTIVE WASTE TANK INSPECTION PROGRAM 2008

    Energy Technology Data Exchange (ETDEWEB)

    West, B.; Waltz, R.

    2009-06-11

    Aqueous radioactive wastes from Savannah River Site (SRS) separations and vitrification processes are contained in large underground carbon steel tanks. Inspections made during 2008 to evaluate these vessels and other waste handling facilities along with evaluations based on data from previous inspections are the subject of this report.

  9. Annual Radioactive Waste Tank Inspection Program - 1997

    Energy Technology Data Exchange (ETDEWEB)

    McNatt, F.G. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1998-05-01

    Aqueous radioactive wastes from Savannah River Site (SRS) separations processes are contained in large underground carbon steel tanks. Inspections made during 1997 to evaluate these vessels, and evaluations based on data accrued by inspections performed since the tanks were constructed are the subject of this report.

  10. Annual radioactive waste tank inspection program: 1995

    Energy Technology Data Exchange (ETDEWEB)

    McNatt, F.G. Sr.

    1996-04-01

    Aqueous radioactive wastes from Savannah River Site (SRS) separations processes are contained in large underground carbon steel tanks. Inspections made during 1995 to evaluate these vessels and evaluations based on data accrued by inspections performed since the tanks were constructed are the subject of this report

  11. Annual radioactive waste tank inspection program - 1996

    Energy Technology Data Exchange (ETDEWEB)

    McNatt, F.G.

    1997-04-01

    Aqueous radioactive wastes from Savannah River Site (SRS) separations processes are contained in large underground carbon steel tanks. Inspections made during 1996 to evaluate these vessels, and evaluations based on data accrued by inspections performed since the tanks were constructed, are the subject of this report.

  12. Research on the Compression Algorithm of the Infrared Thermal Image Sequence Based on Differential Evolution and Double Exponential Decay Model

    Directory of Open Access Journals (Sweden)

    Jin-Yu Zhang

    2014-01-01

    Full Text Available This paper has proposed a new thermal wave image sequence compression algorithm by combining double exponential decay fitting model and differential evolution algorithm. This study benchmarked fitting compression results and precision of the proposed method was benchmarked to that of the traditional methods via experiment; it investigated the fitting compression performance under the long time series and improved model and validated the algorithm by practical thermal image sequence compression and reconstruction. The results show that the proposed algorithm is a fast and highly precise infrared image data processing method.

  13. Comprehensive software for the assessment of {sup 222}Rn and {sup 220}Rn decay products based on air sampling measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sima, Octavian [Physics Department, University of Bucharest, Bucharest-Magurele, P.O. Box MG-11, RO-077125 (Romania)], E-mail: octavian.sima@ik.fzk.de

    2009-05-15

    A computational tool dedicated to the measurement of {sup 222}Rn and {sup 220}Rn decay products by air sampling is presented. {alpha}- or {gamma}-spectrometry measurements, gross {alpha} or {beta} counting, as well as a combination of them are considered. Special attention is given to the evaluation of the uncertainty budget of the results. Besides typical applications in the analysis of experimental data, the software can be used for assessing the expected quality of a measurement protocol and for optimizing it, by generating and analyzing sets of realistic synthetic data.

  14. D rare/forbidden decays at BESIII

    CERN Document Server

    Zhao, Ming-Gang

    2016-01-01

    In this document we present the latest result on rare/forbidden decays for D mesons at the BESIII experiment. Based on 2.92/fb data taken at the center-of-mass energy 3.773 GeV with the BESIII detector, the flavor-changing neutral current process of neutral D decays into two gammas is searched using a double tag technique, while the decays of charged D decays into a charged kaon/pion plus two electrons/positrons are studied based on a single tag method. The resulting upper limits are still above the Standard Model predictions.

  15. Current and future searches for neutrinoless double beta decay

    Science.gov (United States)

    Dolinski, Michelle J.

    2016-09-01

    With the discovery of neutrino oscillations and neutrino mass, it has become a pressing question whether neutrinos have distinct antiparticle states. The most practical experimental approach to answering this question is the search for neutrinoless double beta decay, a version of a rare nuclear process that would violate lepton number conservation. The observation of neutrinoless double beta decay would prove that neutrinos are their own antiparticles. Neutrinoless double beta decay experiments deploy large source masses consisting of a select few (usually enriched) isotopes of interest. Detectors must achieve extremely low levels of radioactive background to detect this rare decay. I will report on recent searches for neutrinoless double beta decay and discuss the technical challenges that the next generation of experiments will overcome.

  16. Near Field sorption Data Bases for Compacted MX-80 Bentonite for Performance Assessment of a High-Level Radioactive Waste Repository in Opalinus Clay Host Rock

    Energy Technology Data Exchange (ETDEWEB)

    Bradbury, M.; Baeyens, B

    2003-08-01

    Bentonites of various types and compacted forms are being investigated in many countries as backfill materials in high-level radioactive waste disposal concepts. Nagra is currently considering an Opalinus clay (OPA) formation in the Zuercher Weinland as a potential location for a high-level radioactive waste repository. A compacted MX-80 bentonite is foreseen as a potential backfill material. Performance assessment studies will be performed for this site and one of the requirements for such an assessment are sorption data bases (SDB) for the bentonite near-field. The purpose of this report is to describe the procedures used to develop the SDB. One of the pre-requisites for developing a SDB is a water chemistry for the compacted bentonite porewater. For a number of reasons mentioned in the report, and discussed in more detail elsewhere, this is not a straightforward task. There are considerable uncertainties associated with the major ion concentrations and in particular with the system pH and Eh. The MX-80 SDB was developed for a reference bentonite porewater (pH = 7.25) which was calculated using the reference OPA porewater. In addition, two further SDBs are presented for porewaters calculated at pH values of 6.9 and 7.9 corresponding to lower and upper bound values calculated for the range of groundwater compositions anticipated for the OPA host rock. 'In house' sorption isotherm data were measured for Cs(I), Ni(II), Eu(III), Th(IV), Se(IV) and 1(-1) on the 'as received' MX-80 material equilibrated with a simulated porewater composition. Complementary 'in house' sorption edge and isotherm measurements on conditioned Na/Ca montmorillonites were also available for many of these radionuclides. These data formed the core of the SDB. Nevertheless, some of the required sorption data still had to be obtained from the open literature. An important part of this report is concerned with describing selection procedures and the modifications

  17. Assessment of temporal trend of radiation dose to the public living in the large area contaminated with radioactive materials after a nuclear power plant accident

    Energy Technology Data Exchange (ETDEWEB)

    Go, A Ra; Kim, Min Jun; Kim, Kwang Pyo [Dept. of Nuclear Engineering, Kyung Hee University, Seoul (Korea, Republic of); Cho, Nam Chan; Seol, Jeung Gun [Radiation Safety Team, Korea Electric Power Corporation Nuclear Fuel, Seoul (Korea, Republic of)

    2015-12-15

    It has been about 5 years since the Fukushima nuclear power plant accident, which contaminated large area with radioactive materials. It is necessary to assess radiation dose to establish evacuation areas and to set decontamination goal for the large contaminated area. In this study, we assessed temporal trend of radiation dose to the public living in the large area contaminated with radioactive materials after the Fukushima nuclear power plant accident. The dose assessment was performed based on Chernobyl model and RESRAD model for two evacuation lift areas, Kawauchi and Naraha. It was reported that deposition densities in the areas were 4.3-96 kBq m{sup -2} for {sup 134}Cs, 1.4-300 kBq m{sup -2} for {sup 137}Cs, respectively. Radiation dose to the residents depended on radioactive cesium concentrations in the soil, ranging 0.11-2.4 mSv y{sup -1} at Kawauchi area and 0.69-1.1 mSv y{sup -1} at Naraha area in July 2014. The difference was less than 5% in radiation doses estimated by two different models. Radiation dose decreased with calendar time and the decreasing slope varied depending on dose assessment models. Based on the Chernobyl dosimetry model, radiation doses decreased with calendar time to about 65% level of the radiation dose in 2014 after 1 year, 11% level after 10 years, and 5.6% level after 30 years. RESRAD dosimetry model more slowly decreased radiation dose with time to about 85% level after 1 year, 40% level after 10 years, and 15% level after 30 years. The decrease of radiation dose can be mainly attributed into radioactive decays and environmental transport of the radioactive cesium. Only environmental transports of radioactive cesium without consideration of radioactive decays decreased radiation dose additionally 43% after 1 year, 72% after 3 years, 80% after 10 years, and 83% after 30 years. Radiation doses estimated with cesium concentration in the soil based on Chernobyl dosimetry model were compared with directly measured radiation doses

  18. Decay spectroscopy of N < Z nuclei around 100Sn

    Science.gov (United States)

    Park, Joochun (Jason); Eurica Collaboration

    2016-09-01

    Many interesting topics in both nuclear structure and nuclear astrophysics converge on the doubly-magic nucleus 100Sn and nuclei in its vicinity. Among them are the boundaries of proton dripline, the effect of pn interaction in self-conjugate nuclei, and the decay properties required for rp -process calculations in nucleosynthesis models. Despite many studies, experimental knowledge of these nuclides has remained scarce due to low production cross sections and a lack of intense beams. However, record quantities of exotic N = Z isotopes around 100Sn were produced at RIKEN Radioactive Isotope Beam Factory, via fragmentation of a 124Xe beam on a thin 9Be target. Based on the obtained data, 89Rh and 93Ag have been confirmed to be proton unbound. Half-lives of isotopes near the proton dripline will be presented with improved precision compared to literature values. In addition, strategies to determine Qβ for ft values, and consequently the Fermi/Gamow-Teller transition strengths of these isotope decays will be discussed. Work supported by the Natural Sciences and Engineering Research Council of Canada and the National Research Council of Canada.

  19. Radioactivity and thermalization in the ejecta of compact object mergers and their impact on kilonova light curves

    CERN Document Server

    Barnes, Jennifer; Wu, Meng-Ru; Mart'inez-Pinedo, Gabriel

    2016-01-01

    One of the most promising electromagnetic signatures of compact object mergers are kilonovae: approximately isotropic radioactively-powered transients that peak days to weeks post-merger. Key uncertainties in modeling kilonovae include the emission profiles of the radioactive decay products---non-thermal beta- and alpha-particles, fission fragments, and gamma-rays---and the efficiency with which they deposit their energy in the ejecta. The total radioactive energy and the efficiency of its thermalization sets the luminosity budget and is therefore necessary for predicting kilonova light curves. We outline the uncertainties in r-process decay, describe the physical processes by which the energy of the decay products is absorbed in the ejecta, and present time-dependent thermalization efficiencies for each particle type. We determine the net heating efficiency and explore its dependence on r-process yields---in particular, the production of translead nuclei that undergo alpha-decay---and on the ejecta's mass, v...

  20. Purifications of calcium carbonate and molybdenum oxide powders for neutrinoless double beta decay experiment, AMoRE

    Energy Technology Data Exchange (ETDEWEB)

    Park, HyangKyu [Center for Underground Physics, Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yuseong-gu, Daejeon, Korea, 305-811 (Korea, Republic of)

    2015-08-17

    The AMoRE (Advanced Mo based Rare process Experiment) collaboration is going to use calcium molybdate crystals to search for neutrinoless double beta decay of {sup 100}Mo isotope. In order to make the crystal, we use calcium carbonate and molybdenum oxide powders as raw materials. Therefore it is highly necessary to reduce potential sources for radioactive backgrounds such as U and Th in the powders. In this talk, we will present our studies for purification of calcium carbonate and molybdenum oxide powders.

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

    Science.gov (United States)

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

    2009-07-08

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

  2. Can transmutation replace deep radioactive repositories?; Ersetzt Transmutation die Tiefenlagerung radioaktiver Abfaelle?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-03-15

    This illustrated brief report issued by the Swiss Federal Nuclear Safety Inspectorate (ENSI) takes a look at transmutation - a method to reduce the time taken for the radioactivity of radioactive wastes to decay. The aim of such a reduction is to reduce the amount of space needed for special underground repositories for highly radioactive wastes. Transmutation is briefly described. Nuclear fuel cycles with spent fuel separation and reprocessing is examined. The large-scale feasibility of such methods is looked at and the advantages offered in connection with the design and implementation of deep nuclear waste repositories are discussed.

  3. The ''invisible'' radioactive scale

    Energy Technology Data Exchange (ETDEWEB)

    Bjoernstad, T.; Ramsoey, T

    1999-04-01

    Production and up-concentration of naturally occurring radioactive material (NORM) in the petroleum industry has attracted steadily increasing attention during the last 15 years. Most production engineers today associate this radioactivity with precipitates (scales) and sludges in production tubing, pumps, valves, separators, settling tanks etc., wherever water is being transported or treated. {sup 226}Ra and {sup 228}Ra are the most well known radioactive constituents in scale. Surprisingly little known is the radioactive contamination by {sup 210}Pb and progeny {sup 210}Bi and {sup 210}Po. These are found in combination with {sup 226}Ra in ordinary scale, often in layer of non-radioactive metallic lead in water transportation systems, but also in pure gas and condensate handling systems ''unsupported'' by {sup 226}Ra, but due to transportation and decay of the noble gas {sup 222}Rn in NG/LNG. This latter contamination may be rather thin, in some cases virtually invisible. When, in addition, the radiation energies are low enough for not being detectable on the equipment outer surface, its existence has for most people in the industry been a secret. The report discusses transportation and deposition mechanisms, detection methods and provides some examples of measured results from the North Sea on equipment sent for maintenance. It is concluded that a regular measurement program for this type of contamination should be mandatory under all dismantling processes of transportation and fluid handling equipment for fluids and gases offshore and onshore.

  4. Radioactivities in Low- and Intermediate-Mass Stars

    CERN Document Server

    Lugaro, Maria

    2010-01-01

    Energy in stars is provided by nuclear reactions, which, in many cases, produce radioactive nuclei. When stable nuclei are irradiated by a flux of protons or neutrons, capture reactions push stable matter out of stability into the regime of unstable species. The ongoing production of radioactive nuclei in the deep interior of the Sun via proton-capture reactions is recorded by neutrinos emitted during radioactive decay and detected on Earth. Radioactive nuclei that have relatively long half lives may also be detected in stars via spectroscopic observations and in stardust recovered from primitive meteorites via laboratory analysis. The vast majority of these stardust grains originated from Asymptotic Giant Branch (AGB) stars. This is the final phase in the evolution of stars initially less massive than ~10 solar masses, during which nuclear energy is produced by alternate hydrogen and helium burning in shells above the core. The long-lived radioactive nucleus 26Al is produced in massive AGB stars (>4:5 solar ...

  5. Radioactive Materials Analytical Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Laing, W.R.; Corbin, L.T.

    1979-01-01

    The Radioactive Materials Analytical Laboratory was completed 15 years ago and has been used since as an analytical chemistry support lab for reactor, fuel development, and reprocessing programs. Additions have been made to the building on two occasions, and a third addition is planned for the future. Major maintenance items include replacement of ZnBr/sub 2/ windows, cleanup of lead glass windows, and servicing of the intercell conveyor. An upgrading program, now in progress, includes construction of new hot-cell instrumentation and the installation of new equipment such as an x-ray fluorescence analyzer and a spark source mass spectrometer.

  6. Alpha decay and cluster decay of some neutron-rich actinide nuclei

    Indian Academy of Sciences (India)

    G M CARMEL VIGILA BAI; R NITHYA AGNES

    2017-03-01

    Nuclei in the actinide region are good in exhibiting cluster radioactivity. In the present work, the half-lives of $\\alpha$-decay and heavy cluster emission from certain actinide nuclei have been calculated using cubic plus Yukawa plus exponential model ($\\bf{CYEM}$). Our model has a cubic potential for the overlapping region which is smoothly connected by a Yukawa plus exponential potential for the region after separation. The computed half-lives are compared with those of other theoretical models and are found to be in good agreement with each other. In this work, we have also studied the deformation effects on half-lives of cluster decay. These deformation effects lower the half-life values and it is also found that the neutron-rich parent nuclei slow down the cluster decay process. Geiger–Nuttal plots for various clusters are found to be linear and most of the emitted clusters are $\\alpha$-like nuclei.

  7. 10 CFR 835.209 - Concentrations of radioactive material in air.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Concentrations of radioactive material in air. 835.209... External Exposure § 835.209 Concentrations of radioactive material in air. (a) The derived air... exposures to airborne radioactive material. (b) The estimation of internal dose shall be based on...

  8. Short-lived radioactivity and magma genesis

    Science.gov (United States)

    Gill, James; Condomines, Michel

    1992-09-01

    Short-lived decay products of uranium and thorium have half-lives and chemistries sensitive to the processes and time scales of magma genesis, including partial melting in the mantle and magmatic differentiation in the crust. Radioactive disequilibrium between U-238, Th-230, and Ra-226 is widespread in volcanic rocks. These disequilibria and the isotopic composition of thorium depend especially on the extent and rate of melting as well as the presence and composition of vapor during melting. The duration of mantle melting may be several hundred millennia, whereas ascent times are a few decades to thousands of years. Differentiation of most magmas commonly occurs within a few millennia, but felsic ones can be tens of millennia old upon eruption.

  9. Radioactive sample effects on EDXRF spectra

    Energy Technology Data Exchange (ETDEWEB)

    Worley, Christopher G [Los Alamos National Laboratory

    2008-01-01

    Energy dispersive X-ray fluorescence (EDXRF) is a rapid, straightforward method to determine sample elemental composition. A spectrum can be collected in a few minutes or less, and elemental content can be determined easily if there is adequate energy resolution. Radioactive alpha emitters, however, emit X-rays during the alpha decay process that complicate spectral interpretation. This is particularly noticeable when using a portable instrument where the detector is located in close proximity to the instrument analysis window held against the sample. A portable EDXRF instrument was used to collect spectra from specimens containing plutonium-239 (a moderate alpha emitter) and americium-241 (a heavy alpha emitter). These specimens were then analyzed with a wavelength dispersive XRF (WDXRF) instrument to demonstrate the differences to which sample radiation-induced X-ray emission affects the detectors on these two types of XRF instruments.

  10. Radioactivity measurements principles and practice

    CERN Document Server

    Mann, W B; Spernol, A

    2012-01-01

    The authors have addressed the basic need for internationally consistent standards and methods demanded by the new and increasing use of radioactive materials, radiopharmaceuticals and labelled compounds. Particular emphasis is given to the basic and practical problems that may be encountered in measuring radioactivity. The text provides information and recommendations in the areas of radiation protection, focusing on quality control and the precautions necessary for the preparation and handling of radioactive substances. New information is also presented on the applications of both traditiona

  11. Method for radioactivity monitoring

    Science.gov (United States)

    Umbarger, C. John; Cowder, Leo R.

    1976-10-26

    The disclosure relates to a method for analyzing uranium and/or thorium contents of liquid effluents preferably utilizing a sample containing counting chamber. Basically, 185.7-keV gamma rays following .sup.235 U alpha decay to .sup.231 Th which indicate .sup.235 U content and a 63-keV gamma ray doublet found in the nucleus of .sup.234 Pa, a granddaughter of .sup.238 U, are monitored and the ratio thereof taken to derive uranium content and isotopic enrichment .sup.235 U/.sup.235 U + .sup.238 U) in the liquid effluent. Thorium content is determined by monitoring the intensity of 238-keV gamma rays from the nucleus of .sup.212 Bi in the decay chain of .sup.232 Th.

  12. Radioactivity a very short introduction

    CERN Document Server

    Tuniz, Claudio

    2012-01-01

    Radioactivity: A Very Short Introduction explains radioactivity and discusses its fundamental role in nature. Radioactivity remains misunderstood and feared perhaps because nuclear radiation cannot be detected by human senses, and can undoubtedly do great harm if appropriate precautions are not taken. Radioactivity in the stars and in the Earth and its wide range of applications in biomedicine, science, industry, agriculture are described, as well as the mechanisms of nuclear fission and fusion, and the harnessing of nuclear power. The issues surrounding safety and security and the increasing concerns about nuclear terrorism are also considered.

  13. Semiempirical Molecular Dynamics (SEMD) I: Midpoint-Based Parallel Sparse Matrix-Matrix Multiplication Algorithm for Matrices with Decay.

    Science.gov (United States)

    Weber, Valéry; Laino, Teodoro; Pozdneev, Alexander; Fedulova, Irina; Curioni, Alessandro

    2015-07-14

    In this paper, we present a novel, highly efficient, and massively parallel implementation of the sparse matrix-matrix multiplication algorithm inspired by the midpoint method that is suitable for matrices with decay. Compared with the state of the art in sparse matrix-matrix multiplications, the new algorithm heavily exploits data locality, yielding better performance and scalability, approaching a perfect linear scaling up to a process box size equal to a characteristic length that is intrinsic to the matrices. Moreover, the method is able to scale linearly with system size reaching constant time with proportional resources, also regarding memory consumption. We demonstrate how the proposed method can be effectively used for the construction of the density matrix in electronic structure theory, such as Hartree-Fock, density functional theory, and semiempirical Hamiltonians. We present the details of the implementation together with a performance analysis up to 185,193 processes, employing a Hamiltonian matrix generated from a semiempirical NDDO scheme.

  14. Survey monitoring of environmental radioactivity in Jeju area

    Energy Technology Data Exchange (ETDEWEB)

    U, Zang Kual; Kang, Tae Woo [Jeju National Univ., Jeju (Korea, Republic of)

    2000-12-15

    The project is carried out to monitor the change of environmental radioactivity in Jeju, and to provide a systematic data for radiation monitoring and counter measurement at a radiological emergency situation. Also the survey of natural environmental radioactivities in the samples was conducted to make the reliable data base for evaluation of internal exposure and environmental contamination of radiation. This report contains the data of gamma exposure rates and radioactivities of airborne dust, fallout, precipitation and tap water which were analyzed periodically by Jeju Regional Monitoring Station in 2000. Also it contains the data of natural radioactivity levels of food stuff such as agricultural and marine products, including drinking waters. There was no significant difference in environmental radioactivities between 1999 and 2000.

  15. Planning of low-level radioactive waste management program

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Teruo; Yoneya, Masayuki; Tanabe, Tsutomu; Koakutsu, Masayuki; Miyamoto, Yasuaki [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan). Tokai Works

    2002-09-01

    In order to treat and dispose of the low-level radioactive waste generated from JNC sites safely and rationally, a comprehensive plan managing the generation, treatment, storage and disposal of waste, was formulated. The plan is called ''Low-Level Radioactive Waste Management Program''. Taking into consideration an institutionalization of disposal and based on an investigation of waste properties (type, amount, activity concentration), the appropriate treatment method for disposal was studied, and a fundamental plan for conducting the Low-Level Radioactive Waste Management Program was presented. To achieve disposal of low-level radioactive waste, concrete measures will be taken according to the Low-Level Radioactive Wastes Management Program. The plan will be improved suitably by the result of technical development, and will be reconsidered flexibly after institutionalization by the government. (author)

  16. Flow and Flow Decay of Refractory Castables

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhiqiang; Bjom Myhre; Bjorn Sandberg

    2003-01-01

    Installation of refractoty castables depend not only on flow, but also on how soon the flow is lost because of setting. The loss of flow (flow decay) has always been one of the main problems of refractory castable manufacturers,a problem that has not been too well described in literature. The flow decay has been studied for a castable system based on alumina, pointing out some general trends. The flow decay was found very temperature sensitive, being strongly accelerated by termperature increases. To compensate for excessive flow loss, a retarder like citric acid may be used. Thus flow decay was measured as a function of citric acid (retarder) addition at 35 ℃ .

  17. On the decay of homogeneous isotropic turbulence

    Science.gov (United States)

    Skrbek, L.; Stalp, Steven R.

    2000-08-01

    Decaying homogeneous, isotropic turbulence is investigated using a phenomenological model based on the three-dimensional turbulent energy spectra. We generalize the approach first used by Comte-Bellot and Corrsin [J. Fluid Mech. 25, 657 (1966)] and revised by Saffman [J. Fluid Mech. 27, 581 (1967); Phys. Fluids 10, 1349 (1967)]. At small wave numbers we assume the spectral energy is proportional to the wave number to an arbitrary power. The specific case of power 2, which follows from the Saffman invariant, is discussed in detail and is later shown to best describe experimental data. For the spectral energy density in the inertial range we apply both the Kolmogorov -5/3 law, E(k)=Cɛ2/3k-5/3, and the refined Kolmogorov law by taking into account intermittency. We show that intermittency affects the energy decay mainly by shifting the position of the virtual origin rather than altering the power law of the energy decay. Additionally, the spectrum is naturally truncated due to the size of the wind tunnel test section, as eddies larger than the physical size of the system cannot exist. We discuss effects associated with the energy-containing length scale saturating at the size of the test section and predict a change in the power law decay of both energy and vorticity. To incorporate viscous corrections to the model, we truncate the spectrum at an effective Kolmogorov wave number kη=γ(ɛ/v3)1/4, where γ is a dimensionless parameter of order unity. We show that as the turbulence decays, viscous corrections gradually become more important and a simple power law can no longer describe the decay. We discuss the final period of decay within the framework of our model, and show that care must be taken to distinguish between the final period of decay and the change of the character of decay due to the saturation of the energy containing length scale. The model is applied to a number of experiments on decaying turbulence. These include the downstream decay of turbulence in

  18. decays to baryons

    Indian Academy of Sciences (India)

    Torsten Leddig

    2012-11-01

    From inclusive measurements, it is known that about 7% of all mesons decay into final states with baryons. In these decays, some striking features become visible compared to mesonic decays. The largest branching fractions come with quite moderate multiplicities of 3–4 hadrons. We note that two-body decays to baryons are suppressed relative to three- and four-body decays. In most of these analyses, the invariant baryon–antibaryon mass shows an enhancement near the threshold. We propose a phenomenological interpretation of this quite common feature of hadronization to baryons.

  19. Weak decays. [Lectures, phenomenology

    Energy Technology Data Exchange (ETDEWEB)

    Wojcicki, S.

    1978-11-01

    Lectures are given on weak decays from a phenomenological point of view, emphasizing new results and ideas and the relation of recent results to the new standard theoretical model. The general framework within which the weak decay is viewed and relevant fundamental questions, weak decays of noncharmed hadrons, decays of muons and the tau, and the decays of charmed particles are covered. Limitation is made to the discussion of those topics that either have received recent experimental attention or are relevant to the new physics. (JFP) 178 references

  20. Rapid screening of radioactivity in food for emergency response.

    Science.gov (United States)

    Bari, A; Khan, A J; Semkow, T M; Syed, U-F; Roselan, A; Haines, D K; Roth, G; West, L; Arndt, M

    2011-06-01

    This paper describes the development of methods for the rapid screening of gross alpha (GA) and gross beta (GB) radioactivity in liquid foods, specifically, Tang drink mix, apple juice, and milk, as well as screening of GA, GB, and gamma radioactivity from surface deposition on apples. Detailed procedures were developed for spiking of matrices with (241)Am (alpha radioactivity), (90)Sr/(90)Y (beta radioactivity), and (60)Co, (137)Cs, and (241)Am (gamma radioactivity). Matrix stability studies were performed for 43 days after spiking. The method for liquid foods is based upon rapid digestion, evaporation, and flaming, followed by gas proportional (GP) counting. For the apple matrix, surface radioactivity was acid-leached, followed by GP counting and/or gamma spectrometry. The average leaching recoveries from four different apple brands were between 63% and 96%, and have been interpreted on the basis of ion transport through the apple cuticle. The minimum detectable concentrations (MDCs) were calculated from either the background or method-blank (MB) measurements. They were found to satisfy the required U.S. FDA's Derived Intervention Levels (DILs) in all but one case. The newly developed methods can perform radioactivity screening in foods within a few hours and have the potential to capacity with further automation. They are especially applicable to emergency response following accidental or intentional contamination of food with radioactivity.

  1. Radiological Risk Assessment and Survey of Radioactive Contamination for Foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    Lee, W.R.; Lee, C.W.; Choi, K.S.; and others

    2007-11-15

    After the Chernobyl nuclear accident in 1986, a radiological dose assessment and a survey of a radioactive contamination for foodstuffs have been investigated by many countries such as EU, Japan, USA. In the case of Japan which is similar to our country for the imported regions of foodstuffs, there were some instances of the excess for regulation on the maximum permitted levels of radioactive contamination among some imported foodstuffs. Concerns about the radioactive contamination of foodstuffs are increased because of the recently special situation (Nuclear test of North Korea). The purpose of this study is a radiological dose assessment and a survey of a radioactive contamination for foodstuffs in order to reduce the probability of intake of contaminated foodstuffs. Analytical results of the collected samples are below MDA. In this project, the model of radiological dose assessment via the food chain was also developed and radiological dose assessment was conducted based on surveys results of a radioactive contamination for foodstuffs in the Korean open markets since 2002. The results of radiological dose assessment are far below international reference level. It shows that public radiation exposure via food chain is well controlled within the international guide level. However, the radioactive contamination research of imported foodstuffs should be continuous considering the special situation(nuclear test of North Korea). These results are used to manage the radioactive contamination of the imported foodstuffs and also amend the regulation on the maximum permitted levels of radioactive contamination of foodstuffs.

  2. Rapid screening of radioactivity in food for emergency response

    Energy Technology Data Exchange (ETDEWEB)

    Bari, A., E-mail: axb16@health.state.ny.u [Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201-0509 (United States); Khan, A.J.; Semkow, T.M.; Syed, U.-F.; Roselan, A.; Haines, D.K. [Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12201-0509 (United States); Roth, G. [Department of Environmental Health Sciences, School of Public Health, University at Albany, One University Place, Rensselaer, NY 12144 (United States); West, L.; Arndt, M. [Wisconsin State Laboratory of Hygiene, 2601 Agriculture Drive, Madison, WI 53718 (United States)

    2011-06-15

    This paper describes the development of methods for the rapid screening of gross alpha (GA) and gross beta (GB) radioactivity in liquid foods, specifically, Tang drink mix, apple juice, and milk, as well as screening of GA, GB, and gamma radioactivity from surface deposition on apples. Detailed procedures were developed for spiking of matrices with {sup 241}Am (alpha radioactivity), {sup 90}Sr/{sup 90}Y (beta radioactivity), and {sup 60}Co, {sup 137}Cs, and {sup 241}Am (gamma radioactivity). Matrix stability studies were performed for 43 days after spiking. The method for liquid foods is based upon rapid digestion, evaporation, and flaming, followed by gas proportional (GP) counting. For the apple matrix, surface radioactivity was acid-leached, followed by GP counting and/or gamma spectrometry. The average leaching recoveries from four different apple brands were between 63% and 96%, and have been interpreted on the basis of ion transport through the apple cuticle. The minimum detectable concentrations (MDCs) were calculated from either the background or method-blank (MB) measurements. They were found to satisfy the required U.S. FDA's Derived Intervention Levels (DILs) in all but one case. The newly developed methods can perform radioactivity screening in foods within a few hours and have the potential to capacity with further automation. They are especially applicable to emergency response following accidental or intentional contamination of food with radioactivity.

  3. Ensemble-based simultaneous emission estimates and improved forecast of radioactive pollution from nuclear power plant accidents: application to ETEX tracer experiment.

    Science.gov (United States)

    Zhang, X L; Li, Q B; Su, G F; Yuan, M Q

    2015-04-01

    The accidental release of radioactive materials from nuclear power plant leads to radioactive pollution. We apply an augmented ensemble Kalman filter (EnKF) with a chemical transport model to jointly estimate the emissions of Perfluoromethylcyclohexane (PMCH), a tracer substitute for radionuclides, from a point source during the European Tracer Experiment, and to improve the forecast of its dispersion downwind. We perturb wind fields to account for meteorological uncertainties. We expand the state vector of PMCH concentrations through continuously adding an a priori emission rate for each succeeding assimilation cycle. We adopt a time-correlated red noise to simulate the temporal emission fluctuation. The improved EnKF system rapidly updates (and reduces) the excessively large initial first-guess emissions, thereby significantly improves subsequent forecasts (r = 0.83, p 80% average reduction of the normalized mean square error).

  4. Semileptonic D-decays at BESIII

    CERN Document Server

    An, Fenfen

    2015-01-01

    We present here three analyses of semileptonic $D$-meson decays based on the 2.92 fb$^{-1}$ of data collected by the BESIII experiment in 2010 and 2011 at the $\\psi$(3770) peak. For the decay $D^{+}\\to K^{-}\\pi^{+}e^{+}\

  5. Fundamental symmetries in {sup 21}Na decay

    Energy Technology Data Exchange (ETDEWEB)

    Hoek, D.J. van der; Hoekstra, R.; Jungmann, K.; Kruithof, W.L.; Onderwater, C.J.G.; Sohani, M.; Willmann, L.; Wilschut, H.W. [KVI, University of Groningen, Groningen (Netherlands)

    2009-07-01

    The {beta}-{nu} correlations in {beta}-decay allows searching for contributions that go beyond the V-A description of the Standard Model for the electroweak interaction. We are developing an experimental setup to measure correlations in the {beta}-decay of {sup 21}Na. By trapping the radioactive atoms, the recoiling nucleus (kinetic energy <230 eV) can be measured in a reaction microscope in coincidence with the emitted {beta} particle. The first step is to study {beta}-{nu} correlations that allows to set limits on scalar and tensor contributions. By polarizing the parent nucleus it becomes possible to search for time reversal violation. The production and trapping of {sup 21}Na has been accomplished. Details of the setup with a two laser system and the status of this phase of the program are described.

  6. Study of the radiation and radioactivity in dairy formulas; Estudio de la radiacion y radiactividad en formulas lacteas

    Energy Technology Data Exchange (ETDEWEB)

    Mireles G, F.; Pinedo V, J.L.; Quirino T, L.L.; Davila R, J.I.; Rios M, C.; Leal A, B.; Lopez del Rio, H. [Unidad Academica de Estudios Nucleares, UAZ, Cipres 10, Frac. La Penuela, 98068 Zacatecas (Mexico)]. e-mail: fmireles@cantera.reduaz.mx

    2006-07-01

    The radiation and natural radioactivity is present in the man's food chain, like it is the case of the milk, and it comes from the natural series of radioactive decay of the {sup 238} U, {sup 235} U and {sup 232} Th, and of the {sup 40} K radioisotope. Since the radioisotopes can be found in floor of where its are transferred to the grasses and in the water that serve as food and of drinking to the cows, then to enter the milk and its derived to the human consumption. In this work it is presented the study of the radiation and gamma radioactivity of 40 samples of dairy formulas of the trademarks and presentations more sold in the market of the private and public sectors. The measurements of the gamma ray spectra were carried out with a spectrometry system based on an Hyper pure Germanium detector (HPGe). The detector has a resolution (FWHM) of 1.9 keV for an energy of the gamma ray of 1.332 keV of the {sup 60} Co. This study presents the results of the concentration in activity of dairy formulations of the radioisotopes of interest. Also, the results are related with possible damages to the health. (Author)

  7. CALDER: neutrinoless double-beta decay identification in TeO{sub 2} bolometers with kinetic inductance detectors

    Energy Technology Data Exchange (ETDEWEB)

    Battistelli, E. S. [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); Bellini, F. [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); INFN Sezione di Roma, Rome (Italy); Bucci, C. [INFN Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); Calvo, M. [Institut Néel, CNRS, Saint-Martin-d’Héres (France); Cardani, L. [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); Physics Department, Princeton University, Princeton, NJ (United States); Casali, N. [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); INFN Sezione di Roma, Rome (Italy); Castellano, M. G. [Istituto di Fotonica e Nanotecnologie, CNR, Rome (Italy); Colantoni, I.; Coppolecchia, A. [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); Cosmelli, C.; Cruciani, A.; Bernardis, P. de [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); INFN Sezione di Roma, Rome (Italy); Di Domizio, S. [Dipartimento di Fisica, Università di Genova, Genoa (Italy); INFN Sezione di Genova, Genoa (Italy); D’Addabbo, A. [INFN Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); Martinez, M.; Masi, S. [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); INFN Sezione di Roma, Rome (Italy); Pagnanini, L. [INFN Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); INFN Gran Sasso Science Institute, L’Aquila (Italy); Tomei, C. [INFN Sezione di Roma, Rome (Italy); Vignati, M., E-mail: marco.vignati@roma1.infn.it [Dipartimento di Fisica, Sapienza Università di Roma, Rome (Italy); INFN Sezione di Roma, Rome (Italy)

    2015-07-31

    Next-generation experiments searching for neutrinoless double-beta decay must be sensitive to a Majorana neutrino mass as low as 10 meV. CUORE , an array of 988 TeO{sub 2} bolometers being commissioned at Laboratori Nazionali del Gran Sasso, features an expected sensitivity of 50–130 meV at 90 % C.L. The background is expected to be dominated by α radioactivity, and can be in principle removed by detecting the small amount of Cherenkov light emitted by the β signal. The Cryogenic wide-Area Light Detectors with Excellent Resolution project aims at developing a small prototype experiment consisting of TeO{sub 2} bolometers coupled to high-sensitivity light detectors based on kinetic inductance detectors. The R&D is focused on the light detectors in view of the implementation in a next-generation neutrinoless double-beta decay experiment.

  8. CALDER: neutrinoless double-beta decay identification in TeO{sub 2} bolometers with kinetic inductance detectors

    Energy Technology Data Exchange (ETDEWEB)

    Battistelli, E.S.; Colantoni, I.; Coppolecchia, A. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); Bellini, F.; Casali, N.; Cosmelli, C.; Cruciani, A.; De Bernardis, P.; Martinez, M.; Masi, S.; Vignati, M. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN Sezione di Roma, Rome (Italy); Bucci, C.; D' Addabbo, A. [INFN Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); Calvo, M. [CNRS, Institut Neel, Saint-Martin-d' Heres (France); Cardani, L. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); Princeton University, Physics Department, NJ (United States); Castellano, M.G. [CNR, Istituto di Fotonica e Nanotecnologie, Rome (Italy); Di Domizio, S. [Universita di Genova, Dipartimento di Fisica, Genoa (Italy); INFN Sezione di Genova, Genoa (Italy); Pagnanini, L. [INFN Laboratori Nazionali del Gran Sasso, Assergi, AQ (Italy); INFN Gran Sasso Science Institute, L' Aquila (Italy); Tomei, C. [INFN Sezione di Roma, Rome (Italy)

    2015-08-15

    Next-generation experiments searching for neutrinoless double-beta decay must be sensitive to a Majorana neutrino mass as low as 10 meV. CUORE, an array of 988 TeO{sub 2} bolometers being commissioned at Laboratori Nazionali del Gran Sasso, features an expected sensitivity of 50- 130 meV at 90 % C.L. The background is expected to be dominated by α radioactivity, and can be in principle removed by detecting the small amount of Cherenkov light emitted by the β signal. The Cryogenic wide-Area Light Detectors with Excellent Resolution project aims at developing a small prototype experiment consisting of TeO{sub 2} bolometers coupled to high-sensitivity light detectors based on kinetic inductance detectors. The R and D is focused on the light detectors in view of the implementation in a next-generation neutrinoless double-beta decay experiment. (orig.)

  9. A kinematic model to estimate the effective dose of radioactive isotopes in the human body for radiological protection

    Science.gov (United States)

    Sasaki, S.; Yamada, T.

    2013-12-01

    The great earthquake attacked the north-east area in Japan in March 11, 2011. The system of electrical facilities to control Fukushima Daiichi nuclear power station was completely destroyed by the following tsunamis. From the damaged reactor containment vessels, an amount of radioactive substances had leaked and been diffused in the vicinity of this station. Radiological internal exposure becomes a serious social issue both in Japan and all over the world. The present study provides an easily understandable, kinematic-based model to estimate the effective dose of radioactive substances in a human body by simplified the complicated mechanism of metabolism. International Commission on Radiological Protection (ICRP) has developed an exact model, which is well-known as a standard method to calculate the effective dose for radiological protection. However, owing to that the above method accord too much with the actual mechanism of metabolism in human bodies, it becomes rather difficult for non-professional people of radiology to gasp the whole images of the movement and the influences of radioactive substances in a human body. Therefore, in the present paper we propose a newly-derived and easily-understandable model to estimate the effective dose. The present method is very similar with the traditional and conventional hydrological tank model. Ingestion flux of radioactive substances corresponds to rain intensity and the storage of radioactive substances to the water storage in a basin in runoff analysis. The key of this method is to estimate the energy radiated from the radioactive nuclear disintegration of an atom by using classical theory of E. Fermi of beta decay and special relativity for various kinds of radioactive atoms. The parameters used in this study are only physical half-time and biological half-time, and there are no intentional and operational parameters of coefficients to adjust our theoretical runoff to observation of ICRP. Figure.1 compares time

  10. Trapping of radioactive {sup 21}Na

    Energy Technology Data Exchange (ETDEWEB)

    Kruithof, Wilbert L.; Hoek, Duurt J. van der; Giri, Gouri S.; Hoekstra, Ronnie; Hoekstra, Steven; Jungmann, Klaus; Onderwater, Gerco; Santra, Bodhaditya; Shildling, Praveen D.; Sohani, Moslem; Versolato, Oscar O.; Willmann, Lorenz; Wilschut, Hans W. [Kernfysisch Versneller Instituut, University Groningen (Netherlands)

    2010-07-01

    Radioactive {sup 21}Na atoms in a magneto-optical trap (MOT) provide an excellent opportunity to search for non-Standard Model contributions in the weak interactions. In particular, correlations between the {beta}-particle and the neutrino are sensitive to time reversal symmetry violating effects. The Na isotope is produced at the TRI{mu}P facility of the KVI using intense {sup 20}Ne beams from the AGOR cyclotron on a cooled deuterium target. The isotopes are stopped and re-thermalized in a Thermal Ionizer. They are transported as a low energy ion beam to a MOT cell where they are neutralized and subsequently captured by laser light. The trapped Na atoms will be transferred to a second MOT which is placed inside a reaction microscope to measure the momentum distribution of the recoiling daughter nuclei after the {beta}-decay. The {beta}-particle will be detected in a scintillation detector. These two devices have been characterized. A pulsed UV laser was used to ionize trapped Na atoms in order to simulate the {beta}-decay in the reaction microscope. The momentum distribution of the recoil ions is measured. The setup of the whole experiment will be presented.

  11. Radioactive waste: show time?

    Energy Technology Data Exchange (ETDEWEB)

    Verhoef, E.V. [COVRA N.V., Spanjeweg 1, 4455 TW Nieuwdorp (Netherlands); McCombie, Charles; Chapman, Neil [Arius Association, Taefernstrasse 1, CH-4050 Baden (Switzerland)

    2010-07-01

    The basic concept within both EC funded SAPIERR I and SAPIERR II projects (FP6) is that of one or more geological repositories developed in collaboration by two or more European countries to accept spent nuclear fuel, vitrified high-level waste and other long-lived radioactive waste from those partner countries. The SAPIERR II project (Strategic Action Plan for Implementation of Regional European Repositories) examines in detail issues that directly influence the practicability and acceptability of such facilities. This paper describes the work in the SAPIERR II project (2006-2008) on the development of a possible practical implementation strategy for shared, regional repositories in Europe and lays out the first steps in implementing that strategy. (authors)

  12. Progress on Radioactive Waste Treatment Facilities Construction

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In 2011, five projects were undertaken by radioactive waste projects management department, which are "Cold Commissioning of the Pilot Project on Radioactive Waste Retrieval and Conditioning (abbreviation 'Pilot Project')", "Radioactive Ventilation Project Construction (abbreviation 'Ventilation

  13. PERSPECTIVE: Fireworks and radioactivity

    Science.gov (United States)

    Breitenecker, Katharina

    2009-09-01

    both reaction products and unburnt constituents of a pyrotechnic mixture. One major environmental concern in pyrotechnics focuses on the emission of heavy metals. This is the topic discussed in the article by Georg Steinhauser and Andreas Musilek in this issue [4]. A possible interrelationship between respiratory effects and fireworks emissions of barium-rich aerosols was also raised last year [5]. In recent years the potential hazard of naturally occurring radioactive material has become of importance to the scientific community. Naturally occurring radionuclides can be of terrestrial or cosmological origin. Terrestrial radionuclides were present in the presolar cloud that later contracted in order to build our solar system. These radionuclides—mainly heavy metals—and their non-radioactive isotopes are nowadays fixed in the matrix of the Earth's structure. Usually, their percentage is quite small compared to their respective stable isotopes—though there are exceptions like in the case of radium. The problem with environmental pollution due to naturally occurring radioactive material begins when this material is concentrated due to mining and milling, and later further processed [6]. Environmental pollution due to radioactive material goes back as far as the Copper and Iron Ages, when the first mines were erected in order to mine ores (gold, silver, copper, iron, etc), resulting in naturally occurring radioactive material being set free with other dusts into the atmosphere. So where is the link between pyrotechnics and radioactivity? In this article presented by Georg Steinhauser and Andreas Musilek [4], the pyrotechnic ingredients barium nitrate and strontium nitrate are explored with respect to their chemical similarities to radium. The fundamental question, therefore, was whether radium can be processed together with barium and strontium. If so, the production and ignition of these pyrotechnic ingredients could cause atmospheric pollution with radium aerosols

  14. Whole-Body Counter Evaluation of Internal Radioactive Cesium in Dogs and Cats Exposed to the Fukushima Nuclear Disaster

    Science.gov (United States)

    Wada, Seiichi; Ito, Nobuhiko; Watanabe, Masamichi; Kakizaki, Takehiko; Natsuhori, Masahiro; Kawamata, Jun; Urayama, Yoshio

    2017-01-01

    As a result of the 2011 nuclear incident that occurred at the Fukushima Nuclear Power Plant, a large number of abandoned dogs and cats were left within the disaster zone. A small number of these animals were rescued and cared for at shelters. Prior to the dispersal of these animals to their owners or fosterers, we evaluated the degree of internal radiocesium contamination using a specially designed whole-body counter. We conducted 863 non-invasive measurements of gamma rays due to internal radioactive cesium for 68 dogs and 120 cats at one shelter. After plotting graphs of 137Cs density we generated exponential functions of decay from seven dogs and six cats. From the regression formulae, we were able to determine the biological half-lives as 38.2 days for dogs and 30.8 days for cats. We found that in dogs there was a correlation between the biological half-life of radioactive cesium and age. Using our data, we estimated whole-body densities for each cat and dog at the time when they were rescued. We found that there were deviations in the data distributions among the different species, likely due to the timing of rescue, or living habits prior to rescue. A significant correlation was found when extracted feline reproductive organs were analyzed; the coefficients for the estimation of whole-body densities were approximately 7-fold higher than those based on the extracted feline reproductive organs. This may be due to the fact that majority of the radioactive cesium accumulates within muscular tissue with less distribution in other organs. It is possible to plan the appropriate management period in an animal shelter based on the use of the biological half-life of radioactive cesium calculated in this study. We believe that the correlations we uncovered in this work would be of great use for the management of companion animals in the event of a future nuclear accident. PMID:28099476

  15. Environmental radioactive intercomparison program and radioactive standards program

    Energy Technology Data Exchange (ETDEWEB)

    Dilbeck, G. [Environmental Monitoring Systems Laboratory, Las Vegas, NV (United States)

    1993-12-31

    The Environmental Radioactivity Intercomparison Program described herein provides quality assurance support for laboratories involved in analyzing public drinking water under the Safe Drinking Water Act (SDWA) Regulations, and to the environmental radiation monitoring activities of various agencies. More than 300 federal and state nuclear facilities and private laboratories participate in some phase of the program. This presentation describes the Intercomparison Program studies and matrices involved, summarizes the precision and accuracy requirements of various radioactive analytes, and describes the traceability determinations involved with radioactive calibration standards distributed to the participants. A summary of program participants, sample and report distributions, and additional responsibilities of this program are discussed.

  16. Decay-Assisted Laser Spectroscopy of Neutron-Deficient Francium

    CERN Document Server

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

    2014-01-01

    This paper reports on the hyperfine-structure and radioactive-decay studies of the neutron-deficient francium isotopes $^{202-206}$Fr performed with the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at the ISOLDE facility, CERN. The high resolution innate to collinear laser spectroscopy is combined with the high efficiency of ion detection to provide a highly-sensitive technique to probe the hyperfine structure of exotic isotopes. The technique of decay-assisted laser spectroscopy is presented, whereby the isomeric ion beam is deflected to a decay spectroscopy station for alpha-decay tagging of the hyperfine components. Here, we present the first hyperfine-structure measurements of the neutron-deficient francium isotopes $^{202-206}$Fr, in addition to the identification of the low-lying states of $^{202,204}$Fr performed at the CRIS experiment.

  17. Radioactive liquid wastes discharged to ground in the 200 Areas during 1978

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J. D.; Poremba, B. E.

    1979-03-26

    This document is issued quarterly for the purpose of summarizing the radioactive liquid wastes that have been discharged to the ground in the 200 Areas. In addition to data for 1978, cumulative data since plant startup are presented. Also, in this document is a listing of decayed activity to the various plant sites.

  18. Terrestrial Radioactivity and Gamma-ray Exposure in the United States and Canada: Gridded geographic images

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Aerial gamma-ray surveys measure the gamma-ray flux produced by the radioactive decay of the naturally occurring elements K-40, U-238, and Th-232 in the top few...

  19. Radiotoxicity and decay heat power of spent nuclear fuel of VVER type reactors at long-term storage.

    Science.gov (United States)

    Bergelson, B R; Gerasimov, A S; Tikhomirov, G V

    2005-01-01

    Radiotoxicity and decay heat power of the spent nuclear fuel of VVER-1000 type reactors are calculated during storage time up to 300,000 y. Decay heat power of radioactive waste (radwaste) determines parameters of the heat removal system for the safe storage of spent nuclear fuel. Radiotoxicity determines the radiological hazard of radwaste after its leakage and penetration into the environment.

  20. Radioactive sup 2 sup 2 sup 2 Rn daughter nuclides on a paper strip

    CERN Document Server

    Peralta, L; Ortigão, C

    2003-01-01

    The isotope sup 2 sup 2 sup 2 Rn belongs to the sup 2 sup 3 sup 8 U decay chain and can be obtained from natural mineral sources. The fact that radon is a gas and its radionuclide daughters get implanted on surrounding materials allows a set of different experiments in radiation physics. These experiments range from isotope decay time measurement to alpha, beta and gamma spectroscopy. To solve the radioactive decay chain equations, a simple iterative method is used as an alternative to the exact analytical solution.

  1. Effective Majorana neutrino decay

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Lucia [Instituto de Fisica, Facultad de Ingenieria,Universidad de la Republica, Montevideo (Uruguay); Romero, Ismael; Peressutti, Javier; Sampayo, Oscar A. [Universidad Nacional de Mar del Plata, Departamento de Fisica, Instituto de Investigaciones Fisicas de Mar del Plata (IFIMAR) CONICET, UNMDP, Mar del Plata (Argentina)

    2016-08-15

    We study the decay of heavy sterile Majorana neutrinos according to the interactions obtained from an effective general theory. We describe the two- and three-body decays for a wide range of neutrino masses. The results obtained and presented in this work could be useful for the study of the production and detection of these particles in a variety of high energy physics experiments and astrophysical observations. We show in different figures the dominant branching ratios and the total decay width. (orig.)

  2. Search for new physics with neutrinos at Radioactive Ion Beam facilities

    CERN Document Server

    Espinoza, Catalina; Volpe, Cristina

    2012-01-01

    We propose applications of Radioactive Ion Beam facilities to investigate physics beyond the Standard Model. In particular, we focus on the possible measurement of coherent neutrino-nucleus scattering and on a search for sterile neutrinos, by means of a low energy beta-beam with a Lorentz boost factor $\\gamma \\approx 1$. In the considered setup the collected radioactive ions are sent inside a 4$\\pi$ detector. For the first application we provide the number of events associated with neutrino-nucleus coherent scattering, when the detector is filled in with a noble liquid. For the sterile search we consider that the spherical detector is filled in with a liquid scintillator, and that the neutrino detection channel is inverse-beta decay. We provide the exclusion curves for the sterile neutrino mixing parameters, based upon the 3+1 formalism, depending upon the achievable ion intensity. Our results are obtained both for unbinned and binned events, with binning in energy and in distance. The proposed experiment rep...

  3. Synthesis of gels with basis of titanium tungstates as matrixes of radioactive generators; Sintesis de geles a base de titanio tungstenatos como matrices de generadores radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Galico C, L

    2005-07-01

    synthesis method avoids the manipulation of radioactive material during the synthesis of the gels, process that consumes around 7 hours. Therefore, in base to the studies carried out with titanium molybdates, it is intends in this work, the synthesis of titanium tungstates gels, to be used as matrixes of the generators {sup 188} W / {sup 188} Re. This type of studies has not been reported in the literature, for what is necessary to undertake basic studies on those preparation conditions and the effect of the characteristics of the titanium tungstates gels in the efficiency of the generators. Parameters like the pH of those initial solutions of tungsten and titanium, the molar relation W:Ti and very particularly the drying of the final product are fundamental to determine the preparation conditions of these gels. Therefore, in order to finding new alternatives of production of {sup 188} W {yields} {sup 188} Re, easy to produce and with high titration efficiencies, it is intends in this work, to develop a generator with basis of titanium and tungsten compounds that could be irradiated after their synthesis. (Author)

  4. 秦山核电基地放射性废物减容技术研究%Research on Radioactive Waste Volume Reduction Technology in Qinshan Nuclear Power Base

    Institute of Scientific and Technical Information of China (English)

    康云鼎

    2012-01-01

    分析秦山核电基地放射性废物的现状及其处理与贮存方式,主要研究针对蒸残液固化物、可压缩废物和废树脂3类产生量较大的固体废物的减容技术.研究表明秦山核电基地的放射性废物还有很大的减容空间,并提出增加秦山核电基地固体废物贮存时间5a以上的减容方案,可有效缓解废物贮存库容的压力.%The paper analyzes the present situation of radioactive wastes in Qinshan nuclear power base and its processing and storage, and focuses on the volume reduction technology for large number of solid wastes including steamed residual liquid condensates, compressible waste and waste resin. Research shows that there is great potential for volume reduction of radioactive wastes in Qinshan nuclear power base, and the volume reduction scheme is provided. With the proposed scheme, the storage capacity for solid wastes in Qinshan nuclear power base can be increased by more than 5 years, which will effectively relieve the pressure for waste storage capacity.

  5. Materials characterization of radioactive waste forms using a multi-element detection method based on the instrumental neutron activation analysis. MEDINA; Stoffliche Charakterisierung radioaktiver Abfallprodukte durch ein Multi-Element-Analyseverfahren basierend auf der instrumentellen Neutronen-Aktivierungs-Analyse. MEDINA

    Energy Technology Data Exchange (ETDEWEB)

    Havenith, Andreas Wilhelm

    2015-07-01

    Radioactive waste has to meet the specifications and acceptance criteria defined by national regulatory and management authorities for its intermediate and final storage. In Germany the Federal Office for Radiation Protection (Bundesamt fuer Strahlenschutz - BfS) has established waste acceptance requirements for the Konrad repository. Konrad is the disposal for radioactive waste with negligible heat generation and is located near the city of Salzgitter and is currently under construction. It will start operation not before the year 2021. The waste-acceptance-requirements are derived from a site-specific safety assessment. They include specific requirements on waste forms, packaging as well as limitations to activities of individual radionuclides and limitations to masses of non-radioactive harmful substances. The amount of chemically toxic elements in the waste is limited in order to avoid pollution of underground water reserves. To comply with these requirements every waste package has to be characterised in its radiological and chemical composition. This characterisation can be performed on the basis of existing documentation or, if the documentation is insufficient, on further analytical analysis. Segmented or integral gamma-scanning as well as active or passive neutron counting are used worldwide as the standard measurement methods for the radiological characterisation and quality checking of radioactive waste. These techniques determine the isotope specific activity of waste packages, but they do not allow the detection of non-radioactive hazardous substances inside the waste packages. Against this background the Institute of Nuclear Engineering and Technology Transfer (NET) at RWTH Aachen University and the Institute of Safety Research and Reactor Technology at Forschungszentrum Juelich jointly develop an innovative non-destructive analytical technique called MEDINA - ''Multi-Element Detection based on Instrumental Neutron Activation'' for

  6. High-level radioactive wastes. Supplement 1

    Energy Technology Data Exchange (ETDEWEB)

    McLaren, L.H. (ed.)

    1984-09-01

    This bibliography contains information on high-level radioactive wastes included in the Department of Energy's Energy Data Base from August 1982 through December 1983. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. 1452 citations.

  7. Final disposal of radioactive waste

    Science.gov (United States)

    Freiesleben, H.

    2013-06-01

    In this paper the origin and properties of radioactive waste as well as its classification scheme (low-level waste - LLW, intermediate-level waste - ILW, high-level waste - HLW) are presented. The various options for conditioning of waste of different levels of radioactivity are reviewed. The composition, radiotoxicity and reprocessing of spent fuel and their effect on storage and options for final disposal are discussed. The current situation of final waste disposal in a selected number of countries is mentioned. Also, the role of the International Atomic Energy Agency with regard to the development and monitoring of international safety standards for both spent nuclear fuel and radioactive waste management is described.

  8. SELF SINTERING OF RADIOACTIVE WASTES

    Science.gov (United States)

    McVay, T.N.; Johnson, J.R.; Struxness, E.G.; Morgan, K.Z.

    1959-12-29

    A method is described for disposal of radioactive liquid waste materials. The wastes are mixed with clays and fluxes to form a ceramic slip and disposed in a thermally insulated container in a layer. The temperature of the layer rises due to conversion of the energy of radioactivity to heat boillng off the liquid to fomn a dry mass. The dry mass is then covered with thermal insulation, and the mass is self-sintered into a leach-resistant ceramic cake by further conversion of the energy of radioactivity to heat.

  9. Radioactivity of drinking-water in the vicinity of nuclear power plants in China based on a large-scale monitoring study.

    Science.gov (United States)

    Miao, Xiao-Xiang; Ji, Yan-Qin; Shao, Xian-Zhang; Wang, Huan; Sun, Quan-Fu; Su, Xu

    2013-12-06

    The public concern for radioactivity of drinking-water has been increasing in recent years after the rapid development of nuclear power plants, and especially after the Fukushima nuclear accident. In this study, the radioactivity of water samples collected in the vicinity of nuclear facilities from seven provinces in China was measured and an average annual equivalent effective dose derived from drinking-water ingestion was calculated. The results showed that, in winter and spring, the activities of gross α and β ranged from 0.009 Bq/L to 0.200 Bq/L and from 0.067 Bq/L to 0.320 Bq/L, respectively. While, in summer and autumn, the activities of gross a and β varied from 0.002 Bq/L to 0.175 Bq/L and from 0.060 Bq/L to 0.334 Bq/L. Our results indicated that the gross a and β activities in these measured water samples were below the WHO recommended values (0.5 Bq/L for gross α and 1.0 Bq/L for gross β) and the annual equivalent effective dose derived from drinking-water ingestion was at a safe level.

  10. INTERNAL DOSES OF THREE PERSONS STAYING 110 KM SOUTH OF THE FUKUSHIMA DAIICHI NUCLEAR POWER STATION DURING THE ARRIVAL OF RADIOACTIVE PLUMES BASED ON DIRECT MEASUREMENTS.

    Science.gov (United States)

    Kurihara, Osamu; Nakagawa, Takahiro; Takada, Chie; Tani, Kotaro; Kim, Eunjoo; Momose, Takumaro

    2016-09-01

    The authors describe the results of direct measurements made on three persons who stayed in Tokai-mura, a village located ∼110 km south of the Fukushima Daiichi Nuclear Power Station (FDNPS), during the arrival of significant radioactive plumes released from the FDNPS as a consequence of the Tohoku earthquake/tsunami/FDNPS accident in March 2011. These measurements were made using a NaI(Tl) spectrometer and a whole-body counter shortly after the accident. Their thyroid equivalent doses ((131)I) were estimated to be 0.9-1.4 mSv under the assumption of acute intake via inhalation on 15 March, when the first significant release event was observed. Although greatly depending on the physicochemical form of iodine, the intake amount ratios of (131)I to (137)Cs for the three subjects were calculated as 2.7-3.7, which were much smaller than the radioactivity ratio (7.8) found in air sampling at the same site.

  11. Radioactivity of Drinking-Water in the Vicinity of Nuclear Power Plants in China Based on a Large-Scale Monitoring Study

    Directory of Open Access Journals (Sweden)

    Xiao-Xiang Miao

    2013-12-01

    Full Text Available The public concern for radioactivity of drinking-water has been increasing in recent years after the rapid development of nuclear power plants, and especially after the Fukushima nuclear accident. In this study, the radioactivity of water samples collected in the vicinity of nuclear facilities from seven provinces in China was measured and an average annual equivalent effective dose derived from drinking-water ingestion was calculated. The results showed that, in winter and spring, the activities of gross α and β ranged from 0.009 Bq/L to 0.200 Bq/L and from 0.067 Bq/L to 0.320 Bq/L, respectively. While, in summer and autumn, the activities of gross a and β varied from 0.002 Bq/L to 0.175 Bq/L and from 0.060 Bq/L to 0.334 Bq/L. Our results indicated that the gross a and β activities in these measured water samples were below the WHO recommended values (0.5 Bq/L for gross α and 1.0 Bq/L for gross β and the annual equivalent effective dose derived from drinking-water ingestion was at a safe level.

  12. The development of radioactive sample surrogates for training and exercises

    Energy Technology Data Exchange (ETDEWEB)

    Martha Finck; Bevin Brush; Dick Jansen; David Chamberlain; Don Dry; George Brooks; Margaret Goldberg

    2012-03-01

    The development of radioactive sample surrogates for training and exercises Source term information is required for to reconstruct a device used in a dispersed radiological dispersal device. Simulating a radioactive environment to train and exercise sampling and sample characterization methods with suitable sample materials is a continued challenge. The Idaho National Laboratory has developed and permitted a Radioactive Response Training Range (RRTR), an 800 acre test range that is approved for open air dispersal of activated KBr, for training first responders in the entry and exit from radioactively contaminated areas, and testing protocols for environmental sampling and field characterization. Members from the Department of Defense, Law Enforcement, and the Department of Energy participated in the first contamination exercise that was conducted at the RRTR in the July 2011. The range was contaminated using a short lived radioactive Br-82 isotope (activated KBr). Soil samples contaminated with KBr (dispersed as a solution) and glass particles containing activated potassium bromide that emulated dispersed radioactive materials (such as ceramic-based sealed source materials) were collected to assess environmental sampling and characterization techniques. This presentation summarizes the performance of a radioactive materials surrogate for use as a training aide for nuclear forensics.

  13. Membrane Treatment of Liquid Salt Bearing Radioactive Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Dmitriev, S. A.; Adamovich, D. V.; Demkin, V. I.; Timofeev, E. M.

    2003-02-25

    The main fields of introduction and application of membrane methods for preliminary treatment and processing salt liquid radioactive waste (SLRW) can be nuclear power stations (NPP) and enterprises on atomic submarines (AS) utilization. Unlike the earlier developed technology for the liquid salt bearing radioactive waste decontamination and concentrating this report presents the new enhanced membrane technology for the liquid salt bearing radioactive waste processing based on the state-of-the-art membrane unit design, namely, the filtering units equipped with the metal-ceramic membranes of ''TruMem'' brand, as well as the electrodialysis and electroosmosis concentrators. Application of the above mentioned units in conjunction with the pulse pole changer will allow the marked increase of the radioactive waste concentrating factor and the significant reduction of the waste volume intended for conversion into monolith and disposal. Besides, the application of the electrodialysis units loaded with an ion exchange material at the end polishing stage of the radioactive waste decontamination process will allow the reagent-free radioactive waste treatment that meets the standards set for the release of the decontaminated liquid radioactive waste effluents into the natural reservoirs of fish-farming value.

  14. [Radioactivity of phosphorus implanted TiNi alloy].

    Science.gov (United States)

    Zhao, Xingke; Cai, Wei; Zhao, Liancheng

    2003-09-01

    Exposed to neutron flow, the phosphorus implanted TiNi alloy gets radioactive. This radioactive material is used in vascular stent for prevention and cure of restenosis. Phosphorus implantation is carried out in a plasma immerged ion implantation system, and the dose of phosphorus implantation is in the range of 2-10 x 10(17) cm-2. After ion implantation, the alloy is exposed to the slow neutron flow in a nuclear reactor, the dose of the slow neutron is 1.39-5.88 x 10(19) n/cm2. The radioactivity of the TiNi alloy was measured by liquid scintillation spectrometry and radio-chromic-film dosimetry. The result shows that whether the phosphorus is implanted or not, the TiNi alloy comes to be radioactive after exposure to neutron flow. Just after neutron irradiation, the radiation dose of phosphorus implanted TiNi alloy is about one hundred times higher than that of un-phosphorus implanted TiNi alloy. The radiation difference between phosphorus and un-phosphorus implanted alloy decreases as time elapses. Within three months after neutron irradiation, the average half-decay period of phosphorus implanted TiNi alloy is about 62 days. The radiation ray penetration of phosphorus implanted TiNi alloy is deeper than that of pure 32P; this is of benefit to making radiation uniformity between stent struts and reducing radiation grads beyond the edge of stent.

  15. Precise predictions for CP asymmetries in B decays

    Energy Technology Data Exchange (ETDEWEB)

    Nierste, Ulrich; Frings, Philipp [Institut fuer Theoretische Teilchenphysik, KIT, Karlsruhe (Germany)

    2016-07-01

    The extraction of fundamental CP phases from B{sub d} or B{sub s} decays to charmonium is affected by penguin contributions. We show how these contributions can be calculated with dynamical QCD-based methods and present our predictions for a variety of decay modes and briefly discuss branching ratios in B→ DD decays.

  16. 基于 DSP +USB 的放射性污染监测现场数据采集系统设计%Design of Radioactive Pollution Monitoring Data Acquisition System Based on DSP+USB

    Institute of Scientific and Technical Information of China (English)

    罗勇; 庹先国; 王磊; 张力

    2014-01-01

    针对放射性污染监测现场对现场数据高速、实时采集的需求,设计了一种基于DSP和USB 2.0为核心的放射性信号数据采集系统,并介绍了该系统的总体结构和具体的软硬件实现方案。该系统将DSP高速的运算速度和数据处理能力、FPGA强大的逻辑处理能力以及USB高速传输速度相结合,构建了一套高速实时的放射性数据采集系统,具有速度快、逻辑处理能力强、稳定性高等优点,该系统在现场测试表现出较好的效果。%Focusing on the requests of high speed and real-time acquisition for data in radioactive contamina-tion monitoring site, this project designed data acquisition system of radioactive signal based on DSP and USB 2.0 as foundation, and it also briefly introduced its whole structure and both software and hardware implementa-tion scheme.This system combined the ability of computation speed and data processing from DSP and the abil-ity of excellent logical processing from FPGA and high transmission speed from USB, which created a complete high speed and real-time system for radioactive data acquisition and this system obviously has properties with high speed, excellent logical processing and stability, especially it was able to perfectly perform in site testing.

  17. GEMS: Underwater spectrometer for long-term radioactivity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sartini, Ludovica, E-mail: ludovica.sartini@ingv.i [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Genoa University, Genoa (Italy); Simeone, Francesco; Pani, Priscilla [' Sapienza' University and Istituto Nazionale di Fisica Nucleare (INFN), Sect.Roma, Roma (Italy); Lo Bue, Nadia; Marinaro, Giuditta [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Grubich, Andry; Lobko, Alexander [Institute for Nuclear Problems (INP), Belarus State University, Minsk (Belarus); Etiope, Giuseppe [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Capone, Antonio [' Sapienza' University and Istituto Nazionale di Fisica Nucleare (INFN), Sect.Roma, Roma (Italy); Favali, Paolo [Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sect.Roma 2, Roma (Italy); Gasparoni, Francesco; Bruni, Federico [Tecnomare S.p.A., Venice (Italy)

    2011-01-21

    GEMS (Gamma Energy Marine Spectrometer) is a prototype of an autonomous radioactivity sensor for underwater measurements, developed in the framework for a development of a submarine telescope for neutrino detection (KM3NeT Design Study Project). The spectrometer is highly sensitive to gamma rays produced by {sup 40}K decays but it can detect other natural (e.g., {sup 238}U,{sup 232}Th) and anthropogenic radio-nuclides (e.g., {sup 137}Cs). GEMS was firstly tested and calibrated in the laboratory using known sources and it was successfully deployed for a long-term (6 months) monitoring at a depth of 3200 m in the Ionian Sea (Capo Passero, offshore Eastern Sicily). The instrument recorded data for the whole deployment period within the expected specifications. This monitoring provided, for the first time, a continuous time-series of radioactivity in deep-sea.

  18. Evaluating factors affecting the permeability of emulsions used to stabilize radioactive contamination from a radiological dispersal device.

    Science.gov (United States)

    Fox, Garey A; Medina, Victor F

    2005-05-15

    Present strategies for alleviating radioactive contamination from a radiological dispersal device (RDD) or dirty bomb involve either demolishing and removing radioactive surfaces or abandoning portions of the area near the release point. In both cases, it is imperative to eliminate or reduce migration of the radioisotopes until the cleanup is complete or until the radiation has decayed back to acceptable levels. This research investigated an alternative strategy of using emulsions to stabilize radioactive particulate contamination. Emergency response personnel would coat surfaces with emulsions consisting of asphalt or tall oil pitch to prevent migration of contamination. The site can then be evaluated and cleaned up as needed. In order for this approach to be effective, the treatment must eliminate migration of the radioactive agents in the terror device. Water application is an environmental condition that could promote migration into the external environment. This research investigated the potential for water, and correspondingly contaminant, migration through two emulsions consisting of Topein, a resinous byproduct during paper manufacture. Topein C is an asphaltic-based emulsion and Topein S is a tall oil pitch, nonionic emulsion. Experiments included water adsorption/ mobilization studies, filtration tests, and image analysis of photomicrographs from an environmental scanning electron microscope (ESEM) and a stereomicroscope. Both emulsions were effective at reducing water migration. Conductivity estimates were on the order of 10(-80) cm s(-1) for Topein C and 10(-7) cm s(-1) for Topein S. Water mobility depended on emulsion flocculation and coalescence time. Photomicrographs indicate that Topein S consisted of greater and more interconnected porosity. Dilute foams of isolated spherical gas cells formed when emulsions were applied to basic surfaces. Gas cells rose to the surface and ruptured, leaving void spaces that penetrated throughout the emulsion. These

  19. Rare Semileptonic Charm Decays

    CERN Document Server

    de Boer, Stefan

    2015-01-01

    An analysis of charm mesons decaying semileptonically via Flavor Changing Neutral Currents is presented. We calculate the Wilson coefficients within the Standard Model. A window in the decay distribution, where physics beyond the Standard Model could be measured is identified. Exemplary, we study effects of leptoquark models.

  20. Double beta decay experiments

    CERN Document Server

    Barabash, A S

    2011-01-01

    The present status of double beta decay experiments is reviewed. The results of the most sensitive experiments are discussed. Proposals for future double beta decay experiments with a sensitivity to the $$ at the level of (0.01--0.1) eV are considered.

  1. Observation of semileptonic decay

    Science.gov (United States)

    Albrecht, H.; Cronström, H. I.; Ehrlichmann, H.; Hamacher, T.; Hofmann, R. P.; Kirchhoff, T.; Nau, A.; Nowak, S.; Reidenbach, M.; Reiner, R.; Schröder, H.; Schulz, H. D.; Walter, M.; Wurth, R.; Appuhn, R. D.; Hast, C.; Kolanoski, H.; Lange, A.; Lindner, A.; Mankel, R.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Töpfer, D.; Walther, A.; Wegener, D.; Paulini, M.; Reim, K.; Wegener, H.; Mundt, R.; Oest, T.; Schmidt-Parzefall, W.; Funk, W.; Stiewe, J.; Werner, S.; Ehret, K.; Hölscher, A.; Hofmann, W.; Hüpper, A.; Khan, S.; Knöpfle, K. T.; Spengler, J.; Britton, D. I.; Charlesworth, C. E. K.; Edwards, K. W.; Hyatt, E. R. F.; Kapitza, H.; Krieger, P.; Macfarlane, D. B.; Patel, P. M.; Prentice, J. D.; Saull, P. R. B.; Seidel, S. C.; Tzamariudaki, K.; van de Water, R. G.; Yoon, T.-S.; Reβing, D.; Schmidtler, M.; Schneider, M.; Schubert, K. R.; Strahl, K.; Waldi, R.; Weseler, S.; Kernel, G.; Križan, P.; Križnič, E.; Podobnik, T.; Živko, T.; Jönsson, L.; Balagura, V.; Belyaev, I.; Danilov, M.; Droutskoy, A.; Golutvin, A.; Gorelov, I.; Kostina, G.; Lubimov, V.; Murat, P.; Pakhlov, P.; Ratnikov, F.; Semenov, S.; Shibaev, V.; Soloshenko, V.; Tichomirov, I.; Zaitsev, Yu.; Argus Collaboration

    1993-04-01

    Observation of the semileptonic decay of the charmed baryon ? in the decay channel ? has been made using the ARGUS detector at the e+e- storage ring DORIS II at DESY. The cross section times branching ratio was found to be ?.

  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. Radioactive waste material melter apparatus

    Science.gov (United States)

    Newman, D.F.; Ross, W.A.

    1990-04-24

    An apparatus for preparing metallic radioactive waste material for storage is disclosed. The radioactive waste material is placed in a radiation shielded enclosure. The waste material is then melted with a plasma torch and cast into a plurality of successive horizontal layers in a mold to form a radioactive ingot in the shape of a spent nuclear fuel rod storage canister. The apparatus comprises a radiation shielded enclosure having an opening adapted for receiving a conventional transfer cask within which radioactive waste material is transferred to the apparatus. A plasma torch is mounted within the enclosure. A mold is also received within the enclosure for receiving the melted waste material and cooling it to form an ingot. The enclosure is preferably constructed in at least two parts to enable easy transport of the apparatus from one nuclear site to another. 8 figs.

  4. Consumer Products Containing Radioactive Materials

    Science.gov (United States)

    ... 2010 Health Physics Society Specialists in Radiation Safety Consumer Products Containing Radioactive Materials Everything we encounter in ... eat, the ground we walk upon, and the consumer products we purchase and use. Although many might ...

  5. Radioactive Iodine Treatment for Hyperthyroidism

    Science.gov (United States)

    ... Iodine for Hyperthyroidism Fact Sheet Radioactive Iodine for Hyperthyroidism April, 2012 Download PDFs English Zulu Espanol Editors ... V. Hennessey, MD Leonard Wartofsky, MD What is hyperthyroidism? The thyroid gland, located at the front of ...

  6. Naturally Occurring Radioactive Materials (NORM)

    Energy Technology Data Exchange (ETDEWEB)

    Gray, P. [ed.

    1997-02-01

    This paper discusses the broad problems presented by Naturally Occuring Radioactive Materials (NORM). Technologically Enhanced naturally occuring radioactive material includes any radionuclides whose physical, chemical, radiological properties or radionuclide concentration have been altered from their natural state. With regard to NORM in particular, radioactive contamination is radioactive material in an undesired location. This is a concern in a range of industries: petroleum; uranium mining; phosphorus and phosphates; fertilizers; fossil fuels; forestry products; water treatment; metal mining and processing; geothermal energy. The author discusses in more detail the problem in the petroleum industry, including the isotopes of concern, the hazards they present, the contamination which they cause, ways to dispose of contaminated materials, and regulatory issues. He points out there are three key programs to reduce legal exposure and problems due to these contaminants: waste minimization; NORM assesment (surveys); NORM compliance (training).

  7. QCD in heavy quark production and decay

    Energy Technology Data Exchange (ETDEWEB)

    Wiss, J. [Univ. of Illinois, Urbana, IL (United States)

    1997-06-01

    The author discusses how QCD is used to understand the physics of heavy quark production and decay dynamics. His discussion of production dynamics primarily concentrates on charm photoproduction data which are compared to perturbative QCD calculations which incorporate fragmentation effects. He begins his discussion of heavy quark decay by reviewing data on charm and beauty lifetimes. Present data on fully leptonic and semileptonic charm decay are then reviewed. Measurements of the hadronic weak current form factors are compared to the nonperturbative QCD-based predictions of Lattice Gauge Theories. He next discusses polarization phenomena present in charmed baryon decay. Heavy Quark Effective Theory predicts that the daughter baryon will recoil from the charmed parent with nearly 100% left-handed polarization, which is in excellent agreement with present data. He concludes by discussing nonleptonic charm decay which is traditionally analyzed in a factorization framework applicable to two-body and quasi-two-body nonleptonic decays. This discussion emphasizes the important role of final state interactions in influencing both the observed decay width of various two-body final states as well as modifying the interference between interfering resonance channels which contribute to specific multibody decays. 50 refs., 77 figs.

  8. Radioactivity of the Cooling Water

    Science.gov (United States)

    Wigner, E. P.

    1943-03-01

    The most important source of radioactivity at the exit manifold of the pile will be due to O{sup 19}, formed by neutron absorption of O{sup 18}. A recent measurement of Fermi and Weil permits to estimate that it will be safe to stay about 80 minutes daily close to the exit manifolds without any shield. Estimates are given for the radioactivities from other sources both in the neighborhood and farther away from the pile.

  9. Atomic Batteries: Energy from Radioactivity

    OpenAIRE

    Kumar, Suhas

    2015-01-01

    With alternate, sustainable, natural sources of energy being sought after, there is new interest in energy from radioactivity, including natural and waste radioactive materials. A study of various atomic batteries is presented with perspectives of development and comparisons of performance parameters and cost. We discuss radioisotope thermal generators, indirect conversion batteries, direct conversion batteries, and direct charge batteries. We qualitatively describe their principles of operat...

  10. Final disposal of radioactive waste

    OpenAIRE

    Freiesleben H.

    2013-01-01

    In this paper the origin and properties of radioactive waste as well as its classification scheme (low-level waste – LLW, intermediate-level waste – ILW, high-level waste – HLW) are presented. The various options for conditioning of waste of different levels of radioactivity are reviewed. The composition, radiotoxicity and reprocessing of spent fuel and their effect on storage and options for final disposal are discussed. The current situation of final waste disposal in a selected number of c...

  11. Radioactive waste engineering and management

    CERN Document Server

    Nakayama, Shinichi

    2015-01-01

    This book describes essential and effective management for reliably ensuring public safety from radioactive wastes in Japan. This is the first book to cover many aspects of wastes from the nuclear fuel cycle to research and medical use, allowing readers to understand the characterization, treatment and final disposal of generated wastes, performance assessment, institutional systems, and social issues such as intergenerational ethics. Exercises at the end of each chapter help to understand radioactive waste management in context.

  12. Electron-capture decay rate of 7Be@C60 by first-principles calculations based on density functional theory

    NARCIS (Netherlands)

    Morisato, T.; Ohno, K.; Ohtsuki, T.; Hirose, K.; Sluiter, M.; Kawazoe, Y.

    2008-01-01

    Carrying out a first-principles calculation assuming linear relationship between the electron density at Be nucleus and the electron-capture (EC) decay rate, we explained why 7Be@C60 shows higher EC decay rate than 7Be crystal, which was originally found experimentally by Ohtsuki et al. [Phys. Rev.

  13. Neutron and proton shell closure in the superheavy region via cluster radioactivity in 280−314 116 isotopes

    Indian Academy of Sciences (India)

    K P Santhosh; R K Biju

    2009-04-01

    Based on the concept of cold valley in fission and fusion, the radioactive decay of superheavy280−314116 nuclei was studied taking Coulomb and proximity potentials as the interacting barrier. It is found that the inclusion of proximity potential does not change the position of minima but minima become deeper which agrees with the earlier findings of Gupta and co-workers. In addition to alpha particle minima, the other deepest minima occur for 8Be, 12,14C clusters. In the fission region two deep regions are found each consisting of several comparable minima, the first region centred on 208Pb and the second is around 132Sn. The cluster decay half-lives and other characteristics are computed for various clusters ranging from alpha particle to 70Ni. The computed half-lives for alpha decay match with the experimental values and with the values calculated using Viola–Seaborg–Sobiczewski (VSS) systematic. The plots connecting computed values and half-lives against neutron number of daughter nuclei were studied for different clusters and it is found that the next neutron shell closures occur at = 162, 172 and 184. Isotopic and isobaric mass parabolas are studied for various cluster emissions and minima of parabola indicate neutron shell closure at = 162, 184 and proton shell closure at = 114. Our study shows that $^{276}_{162}$114 is the deformed doubly magic and $^{298}_{184}$114 is the spherical doubly magic nuclei.

  14. Review of Monte Carlo simulations for backgrounds from radioactivity

    Science.gov (United States)

    Selvi, Marco

    2013-08-01

    For all experiments dealing with the rare event searches (neutrino, dark matter, neutrino-less double-beta decay), the reduction of the radioactive background is one of the most important and difficult tasks. There are basically two types of background, electron recoils and nuclear recoils. The electron recoil background is mostly from the gamma rays through the radioactive decay. The nuclear recoil background is from neutrons from spontaneous fission, (α, n) reactions and muoninduced interactions (spallations, photo-nuclear and hadronic interaction). The external gammas and neutrons from the muons and laboratory environment, can be reduced by operating the detector at deep underground laboratories and by placing active or passive shield materials around the detector. The radioactivity of the detector materials also contributes to the background; in order to reduce it a careful screening campaign is mandatory to select highly radio-pure materials. In this review I present the status of current Monte Carlo simulations aimed to estimate and reproduce the background induced by gamma and neutron radioactivity of the materials and the shield of rare event search experiment. For the electromagnetic background a good level of agreement between the data and the MC simulation has been reached by the XENON100 and EDELWEISS experiments, using the GEANT4 toolkit. For the neutron background, a comparison between the yield of neutrons from spontaneous fission and (α, n) obtained with two dedicated softwares, SOURCES-4A and the one developed by Mei-Zhang-Hime, show a good overall agreement, with total yields within a factor 2 difference. The energy spectra from SOURCES-4A are in general smoother, while those from MZH presents sharp peaks. The neutron propagation through various materials has been studied with two MC codes, GEANT4 and MCNPX, showing a reasonably good agreement, inside 50% discrepancy.

  15. Intergenerational ethics of high level radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kunihiko [Nagoya Univ., Graduate School of Engineering, Nagoya, Aichi (Japan); Nasu, Akiko; Maruyama, Yoshihiro [Shibaura Inst. of Tech., Tokyo (Japan)

    2003-03-01

    The validity of intergenerational ethics on the geological disposal of high level radioactive waste originating from nuclear power plants was studied. The result of the study on geological disposal technology showed that the current method of disposal can be judged to be scientifically reliable for several hundred years and the radioactivity level will be less than one tenth of the tolerable amount after 1,000 years or more. This implies that the consideration of intergenerational ethics of geological disposal is meaningless. Ethics developed in western society states that the consent of people in the future is necessary if the disposal has influence on them. Moreover, the ethics depends on generally accepted ideas in western society and preconceptions based on racism and sexism. The irrationality becomes clearer by comparing the dangers of the exhaustion of natural resources and pollution from harmful substances in a recycling society. (author)

  16. Rutherford, Radioactivity, and the Atomic Nucleus

    CERN Document Server

    Kragh, Helge

    2012-01-01

    Modern atomic and nuclear physics took its start in the early part of the twentieth century, to a large extent based upon experimental investigations of radioactive phenomena. Foremost among the pioneers of the new kind of physics was Ernest Rutherford, who made fundamental contributions to the structure of matter for more than three decades and, in addition, founded important research schools in Manchester and Cambridge. This paper reviews the most important aspects of Rutherford's scientific work in the period from about 1900 to 1920, and it also refers to some of his last experiments of the 1930s. The emphasis is on his theory of radioactive disintegration (1902), the discovery of the atomic nucleus (1911), and the first artificially produced element transformation (1919). Following the transmutation experiments, Rutherford developed elaborate models of the atomic nucleus, but these turned out to be unsuccessful. Other subjects could be included, but the three mentioned are undoubtedly those of the greates...

  17. Radioactive waste management in the former USSR

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.J.

    1992-06-01

    Radioactive waste materials--and the methods being used to treat, process, store, transport, and dispose of them--have come under increased scrutiny over last decade, both nationally and internationally. Nuclear waste practices in the former Soviet Union, arguably the world's largest nuclear waste management system, are of obvious interest and may affect practices in other countries. In addition, poor waste management practices are causing increasing technical, political, and economic problems for the Soviet Union, and this will undoubtedly influence future strategies. this report was prepared as part of a continuing effort to gain a better understanding of the radioactive waste management program in the former Soviet Union. the scope of this study covers all publicly known radioactive waste management activities in the former Soviet Union as of April 1992, and is based on a review of a wide variety of literature sources, including documents, meeting presentations, and data base searches of worldwide press releases. The study focuses primarily on nuclear waste management activities in the former Soviet Union, but relevant background information on nuclear reactors is also provided in appendixes.

  18. Radioactivity in the Marine Environment 1999

    Energy Technology Data Exchange (ETDEWEB)

    Rudjord, A.L.; Foeyn, L.; Brungot, A.L.; Kolstad, A.K.; Helldal, H.E.; Brown, J.; Iosjpe, M.; Christensen, G.

    2001-07-01

    A new, comprehensive national programme for monitoring of Radioactivity in the Marine Environment (RAME) was established in 1999. This program is based on a proposal developed by the Norwegian Radiation Protection Authority (NRPA), the Institute of Marine Research (IMR), the Directorate for Nature Conservation (DN) and the State pollution authorities (SFT) on behalf of the Ministry of Environment. NRPA, as the responsible authority on radiation protection, co-ordinates the programme whilst sampling at sea is conducted in close co-operation with IMR as part of the regular monitoring of the marine environment and its living resources. The principal objective of the programme is to document levels, distributions and trends of anthropogenic and naturally occurring radionuclides in the North Sea, the Norwegian Sea, the Barents Sea and along the Norwegian coast. The programme also collects updated information on both Norwegian and other sources of radioactive contamination, and carries out assessments of radiation exposures of humans and biota. This new national monitoring programme has been co-ordinated with existing programmes funded by the Ministry of Fisheries. The monitoring programme for Marine Fish and Seafood was established in 1994. In previous reports from the programme established in 1994, (Sickel et al, 1995; Brungot et al, 1997, 1999) information regarding radioactivity in sea water, sediments and seaweed was included. However, the main purpose of this program is to document levels of anthropogenic radionuclides in fish and other seafood caught in Norwegian waters. This information is then made available to the relevant authorities, fishing industries and the general public as documentation regarding the quality of the marine products. The work in this programme is performed as a co-operation between the NRPA and the Directorate of Fisheries. In addition, results from the monitoring program conducted by the National Food Control Authority are also included

  19. Induced radioactivity in a 4 MW target and its surroundings

    CERN Document Server

    Agosteo, Stefano; Otto, Thomas; Silari, Marco

    2003-01-01

    An important aspect of a future CERN Neutrino Factory is the material activation arising from a 2.2 GeV, 4 MW proton beam striking a mercury target. An estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump was performed by the Monte Carlo hadronic cascade code FLUKA. The aim was both to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which will have to be disposed of after the facility has ceased operation.

  20. Determination of (241)Pu by the method of disturbed radioactive equilibrium using 2πα-counting and precision gamma-spectrometry.

    Science.gov (United States)

    Alekseev, I; Kuzmina, T

    2016-04-01

    A simple technique is proposed for the determination of the content of (241)Pu, which is based on disturbance of radioactive equilibrium in the genetically related (237)U←(241)Pu→(241)Am decay chain of radionuclides, with the subsequent use of 2πα-counting and precision gamma-spectroscopy for monitoring the process of restoration of that equilibrium. It has been shown that the data on dynamics of accumulation of the daughter (241)Am, which were obtained from the results of measurements of α- and γ-spectra of the samples, correspond to the estimates calculated for the chain of two genetically related radionuclides, the differences in the estimates of (241)Pu radioactivity not exceeding 2%. Combining the different methods of registration (2πα-counting, semiconductor alpha- and gamma-spectrometry) enables the proposed method to be efficiently applied both for calibration of (241)Pu-sources (from several hundreds of kBq and higher) and for radioisotopic analysis of plutonium mixtures. In doing so, there is a deep purification of (241)Pu from its daughter decay products required due to unavailability of commercial detectors that could make it possible, based only on analysis of alpha-spectra, to conduct quantitative analysis of the content of (238)Pu and (241)Am.

  1. Survey monitoring of environmental radioactivity in Daegu area

    Energy Technology Data Exchange (ETDEWEB)

    Kang, H. D.; Lee, S. Y. [Kyungpook National Univ., Daegu (Korea, Republic of)

    1998-01-15

    The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. Gross beta activities were measured and gamma radionuclides were analysed for the environmental samples of air-borned dust. precipitation. fallout and drinking water collected in Taegu radioactivity monitoring center. and gamma exposure rates were also measured. To establish the basic data base on the environmental radioactivity, gamma radionuclide analyses were carried out for the samples of soil, drinking water, grain, vegetable, milk, and fish which were obtained from 31 different areas, and the spatial gamma exposure rates from 61 different points were also measured in Taegu and Kyungpook region. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region.

  2. A non-radioactive DAPI-based high-throughput in vitro assay to assess Plasmodium falciparum responsiveness to antimalarials--increased sensitivity of P. falciparum to chloroquine in Senegal.

    Science.gov (United States)

    Ndiaye, Daouda; Patel, Vishal; Demas, Allison; LeRoux, Michele; Ndir, Omar; Mboup, Souleymane; Clardy, Jon; Lakshmanan, Viswanathan; Daily, Johanna P; Wirth, Dyann F

    2010-02-01

    The spread of Plasmodium falciparum drug resistance is outpacing new antimalarial development and compromising effective malaria treatment. Combination therapy is widely implemented to prolong the effectiveness of currently approved antimalarials. To maximize utility of available drugs, periodic monitoring of drug efficacy and gathering of accurate information regarding parasite-sensitivity changes are essential. We describe a high-throughput, non-radioactive, field-based assay to evaluate in vitro antimalarial drug sensitivity of P. falciparum isolates from 40 Senegalese patients. Compared with earlier years, we found a significant decrease in chloroquine in vitro and in genotypic resistances (> 50% and > 65%, respectively, in previous studies) with only 23% of isolates showing resistance. This is possibly caused by a withdrawal of chloroquine from Senegal in 2002. We also found a range of artemisinin responses. Prevalence of drug resistance is dynamic and varies by region. Therefore, the implementation of non-radioactive, robust, high-throughput antimalarial sensitivity assays is critical for defining region-specific prophylaxis and treatment guidelines.

  3. A Non-Radioactive DAPI-based High-Throughput In Vitro Assay to Assess Plasmodium falciparum Responsiveness to Antimalarials—Increased Sensitivity of P. falciparum to Chloroquine in Senegal

    Science.gov (United States)

    Ndiaye, Daouda; Patel, Vishal; Demas, Allison; LeRoux, Michele; Ndir, Omar; Mboup, Souleymane; Clardy, Jon; Lakshmanan, Viswanathan; Daily, Johanna P.; Wirth, Dyann F.

    2010-01-01

    The spread of Plasmodium falciparum drug resistance is outpacing new antimalarial development and compromising effective malaria treatment. Combination therapy is widely implemented to prolong the effectiveness of currently approved antimalarials. To maximize utility of available drugs, periodic monitoring of drug efficacy and gathering of accurate information regarding parasite-sensitivity changes are essential. We describe a high-throughput, non-radioactive, field-based assay to evaluate in vitro antimalarial drug sensitivity of P. falciparum isolates from 40 Senegalese patients. Compared with earlier years, we found a significant decrease in chloroquine in vitro and in genotypic resistances (> 50% and > 65%, respectively, in previous studies) with only 23% of isolates showing resistance. This is possibly caused by a withdrawal of chloroquine from Senegal in 2002. We also found a range of artemisinin responses. Prevalence of drug resistance is dynamic and varies by region. Therefore, the implementation of non-radioactive, robust, high-throughput antimalarial sensitivity assays is critical for defining region-specific prophylaxis and treatment guidelines. PMID:20133997

  4. Weak Decay of Hypernuclei

    CERN Document Server

    Alberico, W M

    2004-01-01

    The focus of these Lectures is on the weak decay modes of hypernuclei, with special attention to Lambda-hypernuclei. The subject involves many fields of modern theoretical and experimental physics, from nuclear structure to the fundamental constituents of matter and their interactions. The various weak decay modes of Lambda-hypernuclei are described: the mesonic mode and the non-mesonic ones. The latter are the dominant decay channels of medium--heavy hypernuclei, where, on the contrary, the mesonic decay is disfavoured by Pauli blocking effect on the outgoing nucleon. In particular, one can distinguish between one-body and two-body induced decays. Theoretical models employed to evaluate the (partial and total) decay widths of hypernuclei are illustrated, and their results compared with existing experimental data. Open problems and recent achievements are extensively discussed, in particular the determination of the ratio Gamma_n/Gamma_p, possible tests of the Delta I=1/2 rule in non-mesonic decays and the pu...

  5. Radioactive contamination of BaF2 crystal scintillator

    CERN Document Server

    Polischuk, O G; Bernabei, R; Cappella, F; Caracciolo, V; Cerulli, R; Di Marco, A; Danevich, F A; Incicchitti, A; Poda, D V; Tretyak, V I

    2013-01-01

    Barium fluoride (BaF$_2$) crystal scintillators are promising detectors to search for double beta decay processes in $^{130}$Ba ($Q_{2{\\beta}}$ = 2619(3) keV) and $^{132}$Ba ($Q_{2{\\beta}}$ = 844(1) keV). The $^{130}$Ba isotope is of particular interest because of the indications on 2${\\beta}$ decay found in two geochemical experiments. The radioactive contamination of BaF$_2$ scintillation crystal with mass of 1.714 kg was measured over 113.4 hours in a low-background DAMA/R&D set-up deep underground (3600 m w.e.) at the Gran Sasso National Laboratories of INFN (LNGS, Italy). The half-life of $^{212}$Po (present in the crystal scintillator due to contamination by radium) was estimated as $T_{1/2}$ = 298.8 $\\pm$ 0.8(stat.) $\\pm$ 1.4(syst.) ns by analysis of the events pulse profiles.

  6. Modelling seasonal variations of natural radioactivity in soils: A case study in southern Italy

    Science.gov (United States)

    Guagliardi, Ilaria; Rovella, Natalia; Apollaro, Carmine; Bloise, Andrea; Rosa, Rosanna De; Scarciglia, Fabio; Buttafuoco, Gabriele

    2016-12-01

    The activity of natural radionuclides in soil has become an environmental concern for local public and national authorities because of the harmful effects of radiation exposure on human health. In this context, modelling and mapping the activity of natural radionuclides in soil is an important research topic. The study was aimed to model, in a spatial sense, the soil radioactivity in an urban and peri-urban soils area in southern Italy to analyse the seasonal influence on soil radioactivity. Measures of gamma radiation naturally emitted through the decay of radioactive isotopes (potassium, uranium and thorium) were analysed using a geostatistical approach to map the spatial distribution of soil radioactivity. The activity of three radionuclides was measured at 181 locations using a high-resolution ?-ray spectrometry. To take into account the influence of season, the measurements were carried out in summer and in winter. Activity data were analysed by using a geostatistical approach and zones of relatively high or low radioactivity were delineated. Among the main processes which influence natural radioactivity such as geology, geochemical, pedological, and ecological processes, results of this study showed a prominent control of radio-emission measurements by seasonal changes. Low natural radioactivity levels were measured in December associated with winter weather and moist soil conditions (due to high rainfall and low temperature), and higher activity values in July, when the soil was dry and no precipitations occurred.

  7. Modelling seasonal variations of natural radioactivity in soils: A case study in southern Italy

    Indian Academy of Sciences (India)

    Ilaria Guagliardi; Natalia Rovella; Carmine Apollaro; Andrea Bloise; Rosanna De Rosa; Fabio Scarciglia; Gabriele Buttafuoco

    2016-12-01

    The activity of natural radionuclides in soil has become an environmental concern for local public and national authorities because of the harmful effects of radiation exposure on human health. In this context, modelling and mapping the activity of natural radionuclides in soil is an important research topic. The study was aimed to model, in a spatial sense, the soil radioactivity in an urban and peri-urban soils area in southern Italy to analyse the seasonal influence on soil radioactivity. Measures of gamma radiation naturally emitted through the decay of radioactive isotopes (potassium, uranium and thorium) were analysed using a geostatistical approach to map the spatial distribution of soil radioactivity. The activity of three radionuclides was measured at 181 locations using a high-resolution γ-ray spectrometry. To take into account the influence of season, the measurements were carried out in summer and in winter. Activity data were analysed by using a geostatistical approach and zones of relatively high or low radioactivity were delineated. Among the main processes which influence natural radioactivity such as geology, geochemical, pedological, and ecological processes, results of this study showed a prominent control of radio-emission measurements by seasonal changes. Low natural radioactivity levels were measured in December associated with winter weather and moist soil conditions (due to high rainfall and low temperature), and higher activity values in July, when the soil was dry and no precipitations occurred.

  8. Axions from wall decay

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S; Hagmann, C; Sikivie, P

    2001-01-08

    The authors discuss the decay of axion walls bounded by strings and present numerical simulations of the decay process. In these simulations, the decay happens immediately, in a time scale of order the light travel time, and the average energy of the radiated axions is {approx_equal} 7m{sub a} for v{sub a}/m{sub a} {approx_equal} 500. is found to increase approximately linearly with ln(v{sub a}/m{sub a}). Extrapolation of this behavior yields {approx_equal} 60 m{sub a} in axion models of interest.

  9. Rare decays at LHCb

    CERN Document Server

    Lafferty, George

    2015-01-01

    We review recent results from the LHCb experiment on studies of particle decays that are forbidden or rare in the Standard Model. The studies include searches for lepton flavour violating decays of the $\\tau$ lepton and the $B$ and $D$ mesons, and of $B$ and $D$ meson decays that would be mediated by Majorana neutrinos. Results are also presented for the rare processes $B_s \\to \\mu^+\\mu^-$ and $B^0 \\to \\mu^+\\mu^-$, $D^0 \\to \\pi^+\\pi^-\\mu^+\\mu^-$, $b \\to s\\gamma$ transitions, and $B \\to K^{(*)}\\mu^+\\mu^-$.

  10. Radioactivity monitoring of Irish dairy produce

    Energy Technology Data Exchange (ETDEWEB)

    Kelleher, K. (Radiological Protection Institute of Ireland. Radiation Monitoring, Dublin (Ireland))

    2010-03-15

    Full text: The RPII has been carrying out monitoring of milk and dairy produce since 1986. Milk samples are routinely analysed for radiocaesium and strontium-90 as part of the RPII's environmental monitoring programme to determine the doses received to the Irish population from milk consumption. The method the RPII utilises for determining the Sr-90 activity in milk is by measuring the Cerenkov radiation produced by its daughter 90Y isolated from interfering nuclides such as uranium, thorium, radium and their decay products as well as isotopes of caesium, potassium and strontium by extraction with 10% di-(2-ethylhexyl)phosphate (HDEHP) in toluene. The chemical yield of 90Y is determined by the acidmetric titration of yttrium nitrate carrier with titriplex III. The levels of Sr-90 and dose to the Irish population from milk consumption have been negligible when compared to other radioactive sources in the Irish environment. Other dairy products are analysed for radiocaesium on a routine basis for commercial customers to ensure the levels of radioactivity in the dairy products fall within EC regulations governing the export/import of dairy produce. The export of milk and milk produce from Ireland is a very important industry, 80% of dairy products produced in Ireland are exported and these exports are worth Euro 2.2 billion annually to the Irish economy. The dairy products are analysed by gamma spectroscopy and include full and skim milk powders, butter, casein, cheese, cream, whey and lactose. The levels of radiocaesium in these products are typically below 5 Bk/kg and fall well within the limit of 370 Bq/kg laid down by the European Community in Council Regulation 737/90. Although the levels of these radionuclides are relatively low the RPII recognises the importance of analysing these samples for radioactivity to inform the public, ensure consumer confidence and, more importantly, to maintain a level of expertise in the RPII in these analytical techniques so

  11. Decontamination of radioactive materials (part II)

    Energy Technology Data Exchange (ETDEWEB)

    Akashi, Makoto; Shimomura, Satoshi; Hachiya, Misao [National Inst. of Radiological Sciences, Chiba (Japan)

    1998-06-01

    Drifting agents accelerate the exchange process and thus promote to eliminate radioactive materials from human body. The earlier is the administration of the agent, the more effective is the elimination. Against the uptake of radioiodine by thyroid, anti-thyroid drug like NaI, Lugol`s iodine solution, propylthiouracil and methimazole are recommended. Ammonium chloride can be a solubilizer of radioactive strontium. Diuretics may be useful for excretion of radioisotopes of sodium, chlorine, potassium and hydrogen through diuresis. Efficacy of expectorants and inhalants is not established. Parathyroid extract induces decalcification and thus is useful for elimination of 32P. Steroids are used for compensating adrenal function and for treatment of inflammation and related symptoms. Chelating agents are useful for removing cations and effective when given early after contamination. EDTA and, particularly, DTPA are useful for elimination of heavy metals. For BAL (dimercaprol), its toxicity should be taken into consideration. Penicillamine is effective for removing copper and deferoxamine, for iron. Drugs for following radioisotopes are summarized: Am, As, Ba, Br, Ca, Cf, C, Ce, Cs, Cr, Co, Cm, Eu, fission products, F, Ga, Au, H, In, I, Fe, Kr, La, PB, Mn, Hg, Np, P, Pu, Po, K, Pm, Ra, Rb, Ru, Sc, Ag, Na, Sr, S, Tc, Th, U, Y, Zn and Zr. Lung and bronchia washing are effective for treatment of patients who inhaled insoluble radioactive particles although their risk-benefit should be carefully assessed. The present review is essentially based of NCRP Report No.65. (K.H.) 128 refs.

  12. Heavy flavour decay properties with ATLAS

    CERN Document Server

    Carli, Ina; The ATLAS collaboration

    2016-01-01

    We present the results on CP-violation searches in the Bs system, studied in the decay into J/psi phi, and the Bd system through the comparison of the decay time distributions in the flavour specific state J/psi K* and in the CP eigenstate J/psi KS. We additionally present new results in the search for the rare decays of Bs and Bd into mu+mu-. These searches are based on the full sample of data collected by ATLAS at 7 and 8 TeV collision energy. The consistency with the SM and with other available measurements is discussed.

  13. Weak decays and double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Nicholson, H.W.

    1983-08-01

    Work to measure the ..sigma../sup +/ 0 degree differential cross section in the reaction K/sup -/p ..-->.. ..sigma../sup +/..pi../sup -/ at several incident K/sup -/ momenta between 600 and 800 MeV/c as well as the asymmetries in the decays of polarized ..sigma../sup +/'s into protons and neutral pions and of polarized ..sigma../sup -/'s into neutrons and negative pions in collaboration with experimenters from Yale, Brookhaven, and the University of Pittsburgh (Brookhaven experiment 702) has been completed. Data from this experiment is currently being analyzed at Yale. Work is currently underway to develop and construct an experiment to search for neutrinoless double beta decay in thin foils of Mo/sup 100/ in collaboration with experimenters from Lawrence Berkeley Laboratory. Development work on the solid state silicon detectors should be complete in the next six months and construction should e well underway within the next year.

  14. Non-leptonic decays of beauty decays

    CERN Document Server

    Bigi, Ikaros I; Shifman, M; Uraltsev, N; Vainshtein, A I

    1994-01-01

    "Anyone who keeps the ability to see beauty never grows old" (Franz Kafka). In the last few years considerable progress has been achieved in our understanding of the decays of heavy flavour hadrons. One can now calculate inclusive transition rates in QCD proper through an expansion in inverse powers of the heavy flavour quark mass without recourse to phenomenological assumptions. The non-perturbative contributions are treated systematically in this way; they are found to produce corrections of order a few percent in beauty decays, i.e. typically somewhat smaller than the perturbative corrections. One finds, among other things: (a) The lifetime of $B^-$ mesons is predicted to be longer than that of $B^0$ mesons by several percent. (b) The QCD prediction for the semileptonic branching ratio of $B$ mesons appears to exceed present experimental values.

  15. New measurement of exotic decay of 225Ac by 14C emission

    Science.gov (United States)

    Guglielmetti, A.; Bonetti, R.; Ardisson, G.; Barci, V.; Giles, T.; Hussonnois, M.; Le Du, J. F.; Le Naour, C.; Mikheev, V. L.; Pasinetti, A. L.; Ravn, H. L.; Tretyakova, S. P.; Trubert, D.

    The branching ratio of 225Ac decay by emission of 14C was remeasured under improved experimental conditions by using a radioactive source produced at the ISOLDE mass-separator at CERN and a nuclear track detector technique. The result, B = λ14C/λα = (4.5+/-1.4)10-12, is consistent with the anomalously high value obtained in the 1993 experiment, thus confirming the importance of nuclear-structure effects in this exotic decay.

  16. Development of whole energy absorption spectrometer for decay heat measurement on fusion reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Fujio; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    To measure decay heat on fusion reactor materials irradiated by D-T neutrons, a Whole Energy Absorption Spectrometer (WEAS) consisting of a pair of large BGO (bismuth-germanate) scintillators was developed. Feasibility of decay heat measurement with WEAS for various materials and for a wide range of half-lives (seconds - years) was demonstrated by experiments at FNS. Features of WEAS, such as high sensitivity, radioactivity identification, and reasonably low experimental uncertainty of {approx} 10 %, were found. (author)

  17. Properties of the β-Delayed Proton Decay of 147Er

    Science.gov (United States)

    Ma, Fei; Zhou, Xiao-Hong; Zheng, Yong; Xu, Shu-Wei; Xie, Yuan-Xiang; Chen, Liang; Zhang, Yu-Hu; Li, Zhan-Kui; Qiang, Yun-Hua; Lei, Xiang-Guo; Guo, Ying-Xiang; Guo, Song; Ding, Bing; Wang, Hai-Xia; Li, Guang-Shun; Zhou, Hou-Bing

    2010-06-01

    The β-delayed proton decay of 147Er is studied experimentally using the 68Ni+92 Mo reaction at a beam energy of 383 MeV. Based on a He-jet apparatus coupled with a tape transport system, the β-delayed proton radioactivities both from the νs1/2 ground state and the νh11/2 isomer in 147Er are identified by proton-γ coincidence measurements. By analyzing the time distribution of the 4+ → 2+γ transition in the grand-daughter nucleus 146Dy, a half-life of 1.6 ± 0.2 s is determined for the νh11/2 isomer in 147Er. The half-life for the ground state of 147Er is estimated to be 3.2 ± 1.2 s.

  18. Radiopurity control in the NEXT-100 double beta decay experiment: procedures and initial measurements

    CERN Document Server

    Alvarez, V; Bettini, A; Borges, F I G M; Carcel, S; Castel, J; Catala, J M; Cebrian, S; Cervera, A; Conde, C A N; Dafni, T; Dias, T H V T; Diaz, J; Egorov, M; Esteve, R; Evtoukhovitch, P; Fernandes, L M P; Ferrario, P; Ferreira, A L; Ferrer-Ribas, E; Freitas, E D C; Gehman, V M; Gil, A; Giomataris, I; Goldschmidt, A; Gomez, H; Gomez-Cadenas, J J; Gonzalez, K; Gonzalez-Diaz, D; Gutierrez, R M; Hauptman, J; Morata, J A Hernando; Herrera, D C; Herrero, V; Iguaz, F J; Irastorza, I G; Kalinnikov, V; Labarga, L; Liubarsky, I; Lopes, J A M; Lorca, D; Losada, M; Luzon, G; Mari, A; Martin-Albo, J; Martinez, A; Miller, T; Moiseenko, A; Monrabal, F; Monteiro, C M B; Monzo, J M; Mora, F J; Moutinho, L M; Vidal, J Munoz; da Luz, H Natal; Navarro, G; Nebot, M; Nygren, D; Oliveira, C A B; de Solorzano, A Ortiz; Palma, R; Perez, J; Aparicio, J L Perez; Renner, J; Ripoll, L; Rodriguez, A; Rodriguez, J; Santos, F P; Santos, J M F dos; Segui, L; Serra, L; Shuman, D; Simon, A; Sofka, C; Sorel, M; Toledo, J F; Tomas, A; Torrent, J; Tsamalaidze, Z; Vazquez, D; Velicheva, E; Veloso, J F C A; Villar, J A; Webb, R C; Weber, T; White, J; Yahlali, N

    2012-01-01

    The Neutrino Experiment with a Xenon TPC (NEXT) is intended to investigate the neutrinoless double beta decay of 136Xe, which requires a severe suppression of potential backgrounds. An extensive screening and material selection process is underway for NEXT since the control of the radiopurity levels of the materials to be used in the experimental set-up is a must for rare event searches. First measurements based on Glow Discharge Mass Spectrometry and gamma-ray spectroscopy using ultra-low background germanium detectors at the Laboratorio Subterr\\'aneo de Canfranc (Spain) are described here. Activity results for natural radioactive chains and other common radionuclides are summarized, being the values obtained for some materials like copper and stainless steel very competitive. The implications of these results for the NEXT experiment are also discussed.

  19. Neutrinoless double beta decay

    Indian Academy of Sciences (India)

    Kai Zuber

    2012-10-01

    The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given.

  20. Inflaton decay in supergravity

    Energy Technology Data Exchange (ETDEWEB)

    Endo, M.; Takahashi, F. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Yanagida, T.T. [Tokyo Univ. (Japan). Dept. of Physics]|[Tokyo Univ. (Japan). Research Center for the Early Universe

    2007-06-15

    We discuss inflaton decay in supergravity, taking account of the gravitational effects. It is shown that, if the inflaton has a nonzero vacuum expectation value, it generically couples to any matter fields that appear in the superpotential at the tree level, and to any gauge sectors through anomalies in the supergravity. Through these processes, the inflaton generically decays into the supersymmetry breaking sector, producing many gravitinos. The inflaton also directly decays into a pair of the gravitinos. We derive constraints on both inflation models and supersymmetry breaking scenarios for avoiding overproduction of the gravitinos. Furthermore, the inflaton naturally decays into the visible sector via the top Yukawa coupling and SU(3){sub C} gauge interactions. (orig.)

  1. RARE KAON DECAYS.

    Energy Technology Data Exchange (ETDEWEB)

    LITTENBERG, L.

    2005-07-19

    Lepton flavor violation (LFV) experiments have probed sensitivities corresponding to mass scales of well over 100 TeV, making life difficult for models predicting accessible LFV in kaon decay and discouraging new dedicated experiments of this type.

  2. CLEO Results B Decays

    CERN Document Server

    Cassel, David G

    2001-01-01

    Measurements of many Standard Model constants are clouded by uncertainties in nonperturbative QCD parameters that relate measurable quantities to the underlying parton-level processes. Generally these QCD parameters have been obtained from model calculations with large uncertainties that are difficult to quantify. The CLEO Collaboration has taken a major step towards reducing these uncertainties in determining the CKM matrix elements Vcb and Vub using new measurements of the branching fraction and photon energy spectrum of B -> s gamma decays. This report includes: the new CLEO measurements of B -> s gamma decays, Vcb, and Vub; the first results from CLEO III data -- studies of B -> K pi, pi pi, and K Kbar decays; mention of some other recent CLEO B decay results; and plans for operating CESR and CLEO in the charm threshold region.

  3. Laser assisted {alpha} decay

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda Cortes, Hector Mauricio

    2012-02-01

    Excited or short-lived nuclei often decay by emitting alpha particles that are assumed to be preformed inside the nucleus and confined in the nuclear potential well. In this picture, {alpha} decay refers to the tunneling of the alpha particle through the potential barrier. In this thesis we investigate for the first time how strong laser fields can assist the tunneling of the alpha particle and thus influence the nuclear decay. Generally speaking, laser-assisted {alpha} decay can be described as laser-assisted tunneling of a quasistationary state, i.e, a slowly decaying state. Our theoretical treatment is developed starting from the complex trajectory formulation of the well-known strong-field approximation used to describe laser-induced ionization. We extend this formulation and develop a method to treat the decay of quasistationary states. The effect of both static and optical and X-ray monochromatic fields on the lifetimes and {alpha}-particle emission spectra are investigated for a number of {alpha}-emitting nuclei. We find that even at strong intensities, the laser-induced acceleration of the {alpha} decay is negligible, ranging from a relative modification in the decay rate of 10{sup -3} for static fields of electric field strengths of 10{sup 15} V/m, to 10{sup -8} for strong optical fields with intensities of 10{sup 22} W/cm{sup 2}, and to 10{sup -6} for strong X-ray fields with laser intensities around 10{sup 24} W/cm{sup 2}. However, the effect of the external field is visible in the spectrum of emitted alpha particles, leading in the case of optical fields even to rescattering phenomena for intensities approaching 6 x 10{sup 22} W/cm{sup 2}. The dynamics of the alpha particle in laser fields of intensities below the rescattering limit is investigated.

  4. Solar Neutrino Decay

    CERN Document Server

    Acker, A; Acker, Andy; Pakvasa, Sandip

    1994-01-01

    We re-examine the neutrino decay solution to the solar neutrino problem in light of the new data from Gallex II and Kamiokande III. We compare the experimental data with the solar models of Bahcall and Pinsonneault and Turck-Chieze and find that neutrino decay is ruled out as a solution to the solar neutrino problem at better than the 98\\% c.l. even when solar model uncertainties are taken into account.

  5. Open Flavor Strong Decays

    Science.gov (United States)

    García-Tecocoatzi, H.; Bijker, R.; Ferretti, J.; Galatà, G.; Santopinto, E.

    2016-10-01

    In this contribution, we discuss the results of a QM calculation of the open-flavor strong decays of **** light nucleon resonances. These are the results of a recent calculation, where we used a modified ^3P_0 model for the amplitudes and the U(7) algebraic model and the hypercentral quark model to predict the baryon spectrum. The decay amplitudes are compared with the existing experimental data.

  6. Streamer chamber: pion decay

    CERN Multimedia

    1992-01-01

    The real particles produced in the decay of a positive pion can be seen in this image from a streamer chamber. Streamer chambers consist of a gas chamber through which a strong pulsed electric field is passed, creating sparks as a charged particle passes through it. A magnetic field is added to cause the decay products to follow curved paths so that their charge and momentum can be measured.

  7. Aspects of B decays

    Energy Technology Data Exchange (ETDEWEB)

    Faller, Sven

    2011-03-04

    B-meson decays are a good probe for testing the flavour sector of the standard model of particle physics. The standard model describes at present all experimental data satisfactorily, although some ''tensions'' exist, i.e. two to three sigma deviations from the predictions, in particular in B decays. The arguments against the standard model are thus purely theoretical. These tensions between experimental data and theoretical predictions provide an extension of the standard model by new physics contributions. Within the flavour sector main theoretical uncertainties are related to the hadronic matrix elements. For exclusive semileptonic anti B {yields} D{sup (*)}l anti {nu} decays QCD sum rule techniques, which are suitable for studying hadronic matrix elements, however, with substantial, but estimable hadronic uncertainties, are used. The exploration of new physics effects in B-meson decays is done in an twofold way. In exclusive semileptonic anti B {yields} D{sup (*)}l anti {nu} decays the effect of additional right-handed vector as well as left- and right-handed scalar and tensor hadronic current structures in the decay rates and the form factors are studied at the non-recoil point. As a second approach one studied the non-leptonic B{sup 0}{sub s}{yields}J/{psi}{phi} and B{sup 0}{yields}J/{psi}K{sub S,L} decays discussing CP violating effects in the time-dependent decay amplitudes by considering new physics phase in the B{sup 0}- anti B{sup 0} mixing phase. (orig.)

  8. $\\tau$ decays with neutral kaons

    CERN Document Server

    Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Anderson, K.J.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Bailey, I.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Batley, J.R.; Baumann, S.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Bloodworth, I.J.; Bock, P.; Bohme, J.; Boeriu, O.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couchman, J.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Dallison, S.; Davis, R.; de Roeck, A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanfani, A.; Fanti, M.; Faust, A.A.; Feld, L.; Ferrari, P.; Fiedler, F.; Fierro, M.; Fleck, I.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hajdu, C.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Harel, A.; Hargrove, C.K.; Harin-Dirac, M.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hobson, P.R.; Hocker, James Andrew; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klier, A.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kupper, M.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lauber, J.; Lawson, I.; Layter, J.G.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; Lillich, J.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Marchant, T.E.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Merritt, F.S.; Mes, H.; Meyer, I.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Przybycien, M.; Quadt, A.; Rembser, C.; Rick, H.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Sproston, M.; Stahl, A.; Stephens, K.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Trefzger, T.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Waller, D.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.

    2000-01-01

    The branching ratio of the tau lepton to a neutral K meson is measured from a sample of approximately 200,000 tau decays recorded by the OPAL detector at centre-of-mass energies near the Z0 resonance. The measurement is based on two samples which identify one-prong tau decays with KL and KS mesons. The combined branching ratios are measured to be B(tau- -->pi- K0bar nutau) = (9.33+-0.68+-0.49)x10^-3 B(tau- -->pi- K0bar [>=1pi0] nutau) = (3.24+-0.74+-0.66)x10^-3 B(tau- -->K- K0bar [>=0pi0] nutau) = (3.30+-0.55+-0.39)x10^-3 where the first error is statistical and the second systematic.

  9. Leptonic Decays of Charged Pseudoscalar Mesons - 2015

    CERN Document Server

    Rosner, Jonathan L; Van de Water, Ruth S

    2015-01-01

    We review the physics of purely leptonic decays of $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of the constituent quarks and a strong interaction parameter related to the overlap of the quark and antiquark wave-functions in the meson, called the decay constant $f_P$. The leptonic decay constants for $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ mesons can be obtained with controlled theoretical uncertainties and high precision from {\\it ab initio} lattice-QCD simulations. The combination of experimental leptonic decay-rate measurements and theoretical decay-constant calculations enables the determination of several elements of the CKM matrix within the standard model. These determinations are competitive with those obtained from semileptonic decays, and also complementary because they are sensitive to different quark flavor-changing currents. They can also be use...

  10. Technical evaluation of proposed Ukrainian Central Radioactive Waste Processing Facility

    Energy Technology Data Exchange (ETDEWEB)

    Gates, R.; Glukhov, A.; Markowski, F.

    1996-06-01

    This technical report is a comprehensive evaluation of the proposal by the Ukrainian State Committee on Nuclear Power Utilization to create a central facility for radioactive waste (not spent fuel) processing. The central facility is intended to process liquid and solid radioactive wastes generated from all of the Ukrainian nuclear power plants and the waste generated as a result of Chernobyl 1, 2 and 3 decommissioning efforts. In addition, this report provides general information on the quantity and total activity of radioactive waste in the 30-km Zone and the Sarcophagus from the Chernobyl accident. Processing options are described that may ultimately be used in the long-term disposal of selected 30-km Zone and Sarcophagus wastes. A detailed report on the issues concerning the construction of a Ukrainian Central Radioactive Waste Processing Facility (CRWPF) from the Ukrainian Scientific Research and Design institute for Industrial Technology was obtained and incorporated into this report. This report outlines various processing options, their associated costs and construction schedules, which can be applied to solving the operating and decommissioning radioactive waste management problems in Ukraine. The costs and schedules are best estimates based upon the most current US industry practice and vendor information. This report focuses primarily on the handling and processing of what is defined in the US as low-level radioactive wastes.

  11. Exclusive nonleptonic B→VV decays

    Science.gov (United States)

    Barik, N.; Naimuddin, Sk.; Dash, P. C.; Kar, Susmita

    2009-07-01

    The exclusive two-body nonleptonic B→VV decays are investigated, within the factorization approximation, in the relativistic independent quark model based on a confining potential in the scalar-vector harmonic form. The branching ratios and the logitudinal polarization fraction (RL) are calculated yielding the model predictions in agreement with experiment. Our predicted CP-odd fraction (R⊥) for B→D*D(s)* decays are in general agreement with other model predictions and within the existing experimental limit.

  12. Managing radioactive waste produced at secret basic nuclear facilities; La gestion des dechets radioactifs issus des installations nucleaires de base secretes

    Energy Technology Data Exchange (ETDEWEB)

    Elluard, M.P. [Chef de projet a l' Autorite de Surete Nucleaire de Defense - Ministere de la Defense, 75 - Paris (France)

    2011-02-15

    The Delegate for Nuclear Safety and Radiation Protection for National Defence Installations and Activities (DSND) is attached to the French Minister of Defence and the Minister for Industry. The DSND's task is to study and propose to the relevant ministers the specific nuclear safety and radiation protection policy applicable to secret basic nuclear installations (SBNI) classified as such by decision of the Prime Minister. He supervises application of this policy. The DSND draws up the regulations relative to managing waste present within the boundaries of SBNIs in accordance with the guidelines set out in the Environmental Code. Thus, the Title VI of the Order of 26 September 2007 setting out the general technical regulations designed to prevent and limit pollution and external risks resulting from the operation of secret basic nuclear installations recalls the requirement for all SBNI operators to take every precaution necessary to reduce the volume and the radiological, chemical and biological toxicity of all waste produced at its installations and to optimise its management, whilst giving priority to recycling and processing rather than final disposal, which is to be reserved for final waste. The DSND supervises and monitors safety at every stage in radioactive waste management: production, processing, storage, transportation and disposal. (author)

  13. Illustration of sampling-based approaches to the calculation of expected dose in performance assessments for the proposed high level radioactive waste repository at Yucca Mountain, Nevada.

    Energy Technology Data Exchange (ETDEWEB)

    Helton, Jon Craig (Arizona State University, Tempe, AZ); Sallaberry, Cedric J. PhD. (.; .)

    2007-04-01

    A deep geologic repository for high level radioactive waste is under development by the U.S. Department of Energy at Yucca Mountain (YM), Nevada. As mandated in the Energy Policy Act of 1992, the U.S. Environmental Protection Agency (EPA) has promulgated public health and safety standards (i.e., 40 CFR Part 197) for the YM repository, and the U.S. Nuclear Regulatory Commission has promulgated licensing standards (i.e., 10 CFR Parts 2, 19, 20, etc.) consistent with 40 CFR Part 197 that the DOE must establish are met in order for the YM repository to be licensed for operation. Important requirements in 40 CFR Part 197 and 10 CFR Parts 2, 19, 20, etc. relate to the determination of expected (i.e., mean) dose to a reasonably maximally exposed individual (RMEI) and the incorporation of uncertainty into this determination. This presentation describes and illustrates how general and typically nonquantitive statements in 40 CFR Part 197 and 10 CFR Parts 2, 19, 20, etc. can be given a formal mathematical structure that facilitates both the calculation of expected dose to the RMEI and the appropriate separation in this calculation of aleatory uncertainty (i.e., randomness in the properties of future occurrences such as igneous and seismic events) and epistemic uncertainty (i.e., lack of knowledge about quantities that are poorly known but assumed to have constant values in the calculation of expected dose to the RMEI).

  14. Discovery of novel inhibitors of human S-adenosylmethionine decarboxylase based on in silico high-throughput screening and a non-radioactive enzymatic assay.

    Science.gov (United States)

    Liao, Chenzeng; Wang, Yanlin; Tan, Xiao; Sun, Lidan; Liu, Sen

    2015-06-01

    Natural polyamines are small polycationic molecules essential for cell growth and development, and elevated level of polyamines is positively correlated with various cancers. As a rate-limiting enzyme of the polyamine biosynthetic pathway, S-adenosylmethionine decarboxylase (AdoMetDC) has been an attractive drug target. In this report, we present the discovery of novel human AdoMetDC (hAdoMetDC) inhibitors by coupling computational and experimental tools. We constructed a reasonable computational structure model of hAdoMetDC that is compatible with general protocols for high-throughput drug screening, and used this model in in silico screening of hAdoMetDC inhibitors against a large compound library using a battery of computational tools. We also established and validated a simple, economic, and non-radioactive enzymatic assay, which can be adapted for experimental high-throughput screening of hAdoMetDC inhibitors. Finally, we obtained an hAdoMetDC inhibitor lead with a novel scaffold. This study provides both new tools and a new lead for the developing of novel hAdoMetDC inhibitors.

  15. Final disposal of radioactive waste

    Directory of Open Access Journals (Sweden)

    Freiesleben H.

    2013-06-01

    Full Text Available In this paper the origin and properties of radioactive waste as well as its classification scheme (low-level waste – LLW, intermediate-level waste – ILW, high-level waste – HLW are presented. The various options for conditioning of waste of different levels of radioactivity are reviewed. The composition, radiotoxicity and reprocessing of spent fuel and their effect on storage and options for final disposal are discussed. The current situation of final waste disposal in a selected number of countries is mentioned. Also, the role of the International Atomic Energy Agency with regard to the development and monitoring of international safety standards for both spent nuclear fuel and radioactive waste management is described.

  16. Low-level Radioactivity Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hurtgen, C

    2001-04-01

    The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advice the nuclear and non-nuclear industry in matters concerning radioactive contamination and/or low-level radioactivity measurements; (4) to maintain the quality assurance system according to the EN45001/ISO17025 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 2000 are reported.

  17. Low-level Radioactivity Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hurtgen, C

    2002-04-01

    The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advise the nuclear and non-nuclear industry on problems of radioactive contamination and low-level radioactivity measurements; (4) to maintain and improve the quality assurance system according to the ISO17025 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 2001 are reported.

  18. Extensions of Natural Radioactivity to 4th-Type and of the Periodic Table to Super-heavy Nuclei: Contribution of Raj K Gupta to Cold Nuclear Phenomena

    Directory of Open Access Journals (Sweden)

    BirBikram Singh

    2014-02-01

    Full Text Available We have studied here the contribution of Indian Scientists associated with Prof. Raj K. Gupta to cold nuclear phenomena during the last almost four decades, which led to the discovery of fourth kind of natural radioactivity (also known as Cluster Radioactivity, CR and to the extension of periodic table to super heavy nuclei. It is exclusively pointed out how the Quantum Mechanical Fragmentation Theory (QMFT advanced by Prof. Raj K. Gupta and Collaborators led to the discovery of unique phenomenon of CR along with the predictions leading to the synthesis of super heavy elements. We have also mentioned the development of dynamical theories based on QMFT, the Preformed Cluster Model(PCM and the dynamical cluster-decay model (DCM, to study the ground and excited state decays of nuclei, respectively, by Gupta and Collaborators. It is matter of great honor and pride for us to bring out this study to enthuse the young researchers to come up with novel ideas and have inspiration from the scientific contributions of Prof. Raj K. Gupta who is coincidentally celebrating his platinum jubilee birthday anniversary this year.

  19. Vibrational algorithms for quantitative crystallographic analyses of hydroxyapatite-based biomaterials: II, application to decayed human teeth.

    Science.gov (United States)

    Adachi, Tetsuya; Pezzotti, Giuseppe; Yamamoto, Toshiro; Ichioka, Hiroaki; Boffelli, Marco; Zhu, Wenliang; Kanamura, Narisato

    2015-05-01

    A systematic investigation, based on highly spectrally resolved Raman spectroscopy, was undertaken to research the efficacy of vibrational assessments in locating chemical and crystallographic fingerprints for the characterization of dental caries and the early detection of non-cavitated carious lesions. Raman results published by other authors have indicated possible approaches for this method. However, they conspicuously lacked physical insight at the molecular scale and, thus, the rigor necessary to prove the efficacy of this spectroscopy method. After solving basic physical challenges in a companion paper, we apply them here in the form of newly developed Raman algorithms for practical dental research. Relevant differences in mineral crystallite (average) orientation and texture distribution were revealed for diseased enamel at different stages compared with healthy mineralized enamel. Clear spectroscopy features could be directly translated in terms of a rigorous and quantitative classification of crystallography and chemical characteristics of diseased enamel structures. The Raman procedure enabled us to trace back otherwise invisible characteristics in early caries, in the translucent zone (i.e., the advancing front of the disease) and in the body of lesion of cavitated caries.

  20. Induced radioactivity in LDEF components

    Science.gov (United States)

    Harmon, B. A.; Fishman, G. J.; Parnell, T. A.; Laird, C. E.

    1992-01-01

    A systematic study of the induced radioactivity of the Long Duration Exposure Facility (LDEF) is being carried out in order to gather information about the low earth orbit radiation environment and its effects on materials. The large mass of the LDEF spacecraft, its stabilized configuration, and long mission duration have presented an opportunity to determine space radiation-induced radioactivities with a precision not possible before. Data presented include preliminary activities for steel and aluminum structural samples, and activation subexperiment foils. Effects seen in the data show a clear indication of the trapped proton anisotropy in the South Atlantic Anomaly and suggest contributions from different sources of external radiation fluxes.

  1. Reper Radioactive Sources for Time and Energy Calibration of Single Crystal Scintillation Time Spectrometers

    CERN Document Server

    Lebedev, N A; Morozova, N V; Novgorodov, A F; Filossofov, D V

    2000-01-01

    There was made a set of reper radioactive sources for time and energy calibration of the single crystal scintillation time spectrometer. The set consists of ^{73}As, ^{153}Gd, ^{169}Yb, ^{241}Am sources and sources of ^{225}Ac and ^{232}Th including the products of their decay. This set of radioactive sources covers the time interval from 4 ns to 4 mus and energy interval starting from 10 keV. Some of these sources were included in the small size plastic scintillators providing the 4 pi geometry for radiation measurements.

  2. Modelling the Effects of Radioactive Effluent on Thunnus orientalis and Oncorhynchus gorbuscha

    Directory of Open Access Journals (Sweden)

    Zhixiong Chen

    2013-01-01

    Full Text Available The contamination of the Pacific Ocean by the radioactive pollutants released from the Fukushima Daiichi Nuclear Power Plant has raised legitimate concerns over the viability of marine wildlife. We develop a modified Crank-Nicholson method to approximate a solution to the diffusion-advection-decay equation in time and three spatial dimensions to explore the extent of the effects of the radioactive effluent on two marine species: the Pacific Bluefin Tuna (Thunnus orientalis and the Pacific Pink Salmon (Oncorhynchus gorbuscha.

  3. IGRIS for characterizing low-level radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Peters, C.W. [Nuclear Diagnostic Systems, Springfield, VA (United States); Swanson, P.J. [Concord Associates, Knoxville, TN (United States)

    1993-03-01

    A recently developed neutron diagnostic probe system has the potential to noninvasively characterize low-level radioactive waste in bulk soil samples, containers such as 55-gallon barrels, and in pipes, valves, etc. The probe interrogates the target with a low-intensity beam of 14-MeV neutrons produced from the deuterium-tritium reaction in a specially designed sealed-tube neutron-generator (STNG) that incorporates an alpha detector to detect the alpha particle associated with each neutron. These neutrons interact with the nuclei in the target to produce inelastic-, capture-, and decay-gamma rays that are detected by gamma-ray detectors. Time-of-flight methods are used to separate the inelastic-gamma rays from other gamma rays and to determine the origin of each inelastic-gamma ray in three dimensions through Inelastic-Gamma Ray Imaging and Spectroscopy (IGRIS). The capture-gamma ray spectrum is measured simultaneously with the IGRIS measurements. The decay-gamma ray spectrum is measured with the STNG turned off. Laboratory proof-of-concept measurements were used to design prototype systems for Bulk Soil Assay, Barrel Inspection, and Decontamination and Decommissioning and to predict their minimum detectable levels for heavy toxic metals (As, Hg, Cr, Zn, Pb, Ni, and Cd), uranium and transuranics, gamma-ray emitters, and elements such as chlorine, which is found in PCBs and other pollutants. These systems are expected to be complementary and synergistic with other technologies used to characterize low-level radioactive waste.

  4. Highly efficient method for production of radioactive silver seed cores for brachytherapy.

    Science.gov (United States)

    Cardoso, Roberta Mansini; de Souza, Carla Daruich; Rostelato, Maria Elisa Chuery Martins; Araki, Koiti

    2017-02-01

    A simple and highly efficient (shorter reaction time and almost no rework) method for production of iodine based radioactive silver seed cores for brachytherapy is described. The method allows almost quantitative deposition of iodine-131 on dozens of silver substrates at once, with even distribution of activity per core and insignificant amounts of liquid and solid radioactive wastes, allowing the fabrication of cheaper radioactive iodine seeds for brachytherapy.

  5. Theoretical Studies of Proton Radioactivity

    Institute of Scientific and Technical Information of China (English)

    Ldia S Ferreira; Enrico Maglione

    2016-01-01

    In the paper, we will discuss the most recent theoretical approaches developed by our group, to understand the mechanisms of decay by one proton emission, and the structure and shape of exotic nuclei at the limits of stability.

  6. Clays in natural and engineered barriers for radioactive waste confinement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Andra organised an International Symposium on the use of Natural and Engineered Clay-based Barriers for the Containment of Radioactive Waste hold at the Congress Centre of Tours, France, in March 2005. The symposium provided an opportunity to take stock of the potential properties of the clay-based materials present in engineered or natural barriers in order to meet the containment specifications of a deep geological repository for radioactive waste. It was intended for specialists working in the various disciplines involved with clays and clay based minerals, as well as scientists from agencies and organisations dealing with investigations on the disposal of high-level and long-lived radioactive waste. The themes of the Symposium included geology, geochemistry, transfers of materials, alteration processes, geomechanics, as well as the recent developments regarding the characterisation of clays, as well as experiments in surface and underground laboratories. The symposium consisted of plenary sessions, parallel specialized sessions and poster sessions. (author)

  7. Radioactive Ages of Metal-Poor Halo Stars

    Institute of Scientific and Technical Information of China (English)

    Ji Li; Gang Zhao

    2004-01-01

    The abundances of long-lived radioactive elements Th and U observed in metal-poor halo stars can be used as chronometers to determine the age of individual stars, and hence set a lower limit on the age of the Galaxy and hence of the universe.This radioactive dating requires the zero-decay productions of Th and U, which involves complicated r-process nucleosynthesis calculations. Several parametric rprocess models have been used to calculate the initial abundance ratios of Th/Eu and U/Th, but, due to the sharp sensitivity of these models to nuclear physics inputs, the calculations have relatively large uncertainties which lead to large uncertainties in the age determinations. In order to reduce these uncertainties, we present a simple method to estimate the initial productions of Th and U, which only depends on the solar system abundances and the stellar abundances of stable r-process elements.From our calculations of the initial abundance ratios of Th/Eu and U/Th, we reestimate the ages of those very metal-poor halo stars with published abundances of Th and U. Our age estimates are consistent, within the errors, with the other age determinations derived from r-process models, and offer useful constrains for r-process theoretical calculations. The advantages and limitations of our simple method of radioactive dating are discussed.

  8. χ c production in hadronic Z decays

    Science.gov (United States)

    Adriani, O.; Aguilar-Benitez, M.; Ahlen, S.; Alcaraz, J.; Aloisio, A.; Alverson, G.; Alviggi, M. G.; Ambrosi, G.; An, Q.; Anderhub, H.; Anderson, A. L.; Andreev, V. P.; Angelescu, T.; Antonov, L.; Antreasyan, D.; Arce, P.; Arefiev, A.; Atamanchuk, A.; Azemoon, T.; Aziz, T.; Baba, P. V. K. S.; Bagnaia, P.; Bakken, J. A.; Ball, R. C.; Banerjee, S.; Bao, J.; Barillère, R.; Barone, L.; Baschirotto, A.; Battiston, R.; Bay, A.; Becattini, F.; Bechtluft, J.; Becker, R.; Becker, U.; Behner, F.; Behrens, J.; Bencze, Gy. L.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biland, A.; Bilei, G. M.; Bizzarri, R.; Blaising, J. J.; Bobbink, G. J.; Bock, R.; Böhm, A.; Borgia, B.; Bosetti, M.; Bourilkov, D.; Bourquin, M.; Boutigny, D.; Bouwens, B.; Brambilla, E.; Branson, J. G.; Brock, I. C.; Brooks, M.; Bujak, A.; Burger, J. D.; Burger, W. J.; Busenitz, J.; Buytenhuijs, A.; Cai, X. D.; Capell, M.; Caria, M.; Carlino, G.; Cartacci, A. M.; Castello, R.; Cerrada, M.; Cesaroni, F.; Chang, Y. H.; Chaturvedi, U. K.; Chemarin, M.; Chen, A.; Chen, C.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chen, M.; Chen, W. Y.; Chiefari, G.; Chien, C. Y.; Choi, M. T.; Chung, S.; Civinini, C.; Clare, I.; Clare, R.; Coan, T. E.; Cohn, H. O.; Coignet, G.; Colino, N.; Contin, A.; Costantini, S.; Cotorobai, F.; Cui, X. T.; Cui, X. Y.; Dai, T. S.; D'Alessandro, R.; de Asmundis, R.; Degré, A.; Deiters, K.; Dénes, E.; Denes, P.; DeNotaristefani, F.; Dhina, M.; DiBitonto, D.; Diemoz, M.; Dimitrov, H. R.; Dionisi, C.; Dittmar, M.; Djambazov, L.; Dova, M. T.; Drago, E.; Duchesneau, D.; Duinker, P.; Duran, I.; Easo, S.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Erné, F. C.; Extermann, P.; Fabbretti, R.; Fabre, M.; Falciano, S.; Fan, S. J.; Fackler, O.; Fay, J.; Felcini, M.; Ferguson, T.; Fernandez, D.; Fernandez, G.; Ferroni, F.; Fasefeldt, H.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, P. H.; Forconi, G.; Fredj, L.; Freudenreich, K.; Friebel, W.; Fukushima, M.; Gailloud, M.; Galaktionov, Yu.; Gallo, E.; Ganguli, S. N.; Garcia-Abia, P.; Gele, D.; Gentile, S.; Gheordanescu, N.; Giagu, S.; Goldfarb, S.; Gong, Z. F.; Gonzalez, E.; Gougas, A.; Goujon, D.; Gratta, G.; Gruenewald, M.; Gu, C.; Guanziroli, M.; Guo, J. K.; Gupta, V. K.; Gurtu, A.; Gustafson, H. R.; Gutay, L. J.; Hangarter, K.; Hartmann, B.; Hasan, A.; Hauschildt, D.; He, C. F.; He, J. T.; Hebbeker, T.; Hebert, M.; Hervé, A.; Hilgers, K.; Hofer, H.; Hoorani, H.; Hu, G.; Hu, G. Q.; Ille, B.; Ilyas, M. M.; Innocente, V.; Janssen, H.; Jezequel, S.; Jin, B. N.; Jones, L. W.; Josa-Mutuberria, I.; Kasser, A.; Khan, R. A.; Kamyshkov, Yu.; Kapinos, P.; Kapustinsky, J. S.; Karyotakis, Y.; Kaur, M.; Khokhar, S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kim, S. C.; Kim, Y. G.; Kinnison, W. W.; Kirkby, A.; Kirkby, D.; Kirsch, S.; Kittel, W.; Klimentov, A.; Klöckner, R.; König, A. C.; Koffeman, E.; Kornadt, O.; Koutsenko, V.; Koulbardis, A.; Kraemer, R. W.; Kramer, T.; Krastev, V. R.; Krenz, W.; Krivshich, A.; Kuijten, H.; Kumar, K. S.; Kunin, A.; Landi, G.; Lanske, D.; Lanzano, S.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, D. M.; Lee, J. S.; Lee, K. Y.; Leedom, I.; Leggett, C.; Le Goff, J. M.; Leiste, R.; Lenti, M.; Leonardi, E.; Li, C.; Li, H. T.; Li, P. J.; Liao, J. Y.; Lin, W. T.; Lin, Z. Y.; Linde, F. L.; Lindemann, B.; Lista, L.; Liu, Y.; Lohmann, W.; Longo, E.; Lu, Y. S.; Lubbers, J. M.; Lübelsmeyer, K.; Luci, C.; Luckey, D.; Ludovici, L.; Luminari, L.; Lustermann, W.; Ma, J. M.; Ma, W. G.; MacDermott, M.; Malik, R.; Malinin, A.; Maña, C.; Maolinbay, M.; Marchesini, P.; Marion, F.; Marin, A.; Martin, J. P.; Martinez-Laso, L.; Marzano, F.; Massaro, G. G. G.; Mazumdar, K.; McBride, P.; McMahon, T.; McNally, D.; Merk, M.; Merola, L.; Meschini, M.; Metzger, W. J.; Mi, Y.; Mihul, A.; Mills, G. B.; Mir, Y.; Mirabelli, G.; Mnich, J.; Möller, M.; Monteleoni, B.; Morand, R.; Morganti, S.; Moulai, N. E.; Mount, R.; Müller, S.; Nadtochy, A.; Nagy, E.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Neyer, C.; Niaz, M. A.; Nippe, A.; Nowak, H.; Organtini, G.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Pascale, G.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pei, Y. J.; Pensotti, S.; Perret-Gallix, D.; Perrier, J.; Pevsner, A.; Piccolo, D.; Pieri, M.; Piroué, P. A.; Plasil, F.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Qi, Z. D.; Qian, J. M.; Qureshi, K. N.; Raghavan, R.; Rahal-Callot, G.; Rancoita, P. G.; Rattaggi, M.; Raven, G.; Razis, P.; Read, K.; Ren, D.; Ren, Z.; Rescigno, M.; Reucroft, S.; Ricker, A.; Riemann, S.; Riemers, B. C.; Riles, K.; Rind, O.; Rizvi, H. A.; Ro, S.; Rodriguez, F. J.; Roe, B. P.; Röhner, M.; Romero, L.; Rosier-Lees, S.; Rosmalen, R.; Rosselet, Ph.; van Rossum, W.; Roth, S.; Rubbia, A.; Rubio, J. A.; Rykaczewski, H.; Sachwitz, M.; Salicio, J.; Salicio, J. M.; Sanders, G. S.; Santocchia, A.; Sarakinos, M. S.; Sartorelli, G.; Sassowsky, M.; Sauvage, G.; Schegelsky, V.; Schmitz, D.; Schmitz, P.; Schneegans, M.; Schopper, H.; Schotanus, D. J.; Shotkin, S.; Schreiber, H. J.; Shukla, J.; Schulte, R.; Schulte, S.; Schultze, K.; Schwenke, J.; Schwering, G.; Sciacca, C.; Scott, I.; Sehgal, R.; Seiler, P. G.; Sens, J. C.; Servoli, L.; Sheer, I.; Shen, D. Z.; Shevchenko, S.; Shi, X. R.; Shumilov, E.; Shoutko, V.; Son, D.; Sopczak, A.; Soulimov, V.; Spartiotis, C.; Spickermann, T.; Spillantini, P.; Starosta, R.; Steuer, M.; Stickland, D. P.; Sticozzi, F.; Stone, H.; Strauch, K.; Stringfellow, B. C.; Sudhakar, K.; Sultanov, G.; Sun, L. Z.; Susinno, G. F.; Suter, H.; Swain, J. D.; Syed, A. A.; Tang, X. W.; Taylor, L.; Terzi, G.; Ting, Samuel C. C.; Ting, S. M.; Tonutti, M.; Tonwar, S. C.; Tóth, J.; Tsaregorodtsev, A.; Tsipolitis, G.; Tully, C.; Tung, K. L.; Ulbricht, J.; Urbán, L.; Uwer, U.; Valente, E.; Van de Walle, R. T.; Vetlitsky, I.; Viertel, G.; Vikas, P.; Vikas, U.; Vivargent, M.; Vogel, H.; Vogt, H.; Vorobiev, I.; Vorobyov, A. A.; Vuilleumier, L.; Wadhwa, M.; Wallraff, W.; Wang, C.; Wang, C. R.; Wang, X. L.; Wang, Y. F.; Wang, Z. M.; Warner, C.; Weber, A.; Weber, J.; Weill, R.; Wenaus, T. J.; Wenninger, J.; White, M.; Willmott, C.; Wittgenstein, F.; Wright, D.; Wu, S. X.; Wynhoff, S.; Wysłouch, B.; Xie, Y. Y.; Xu, J. G.; Xu, Z. Z.; Xue, Z. L.; Yan, D. S.; Yang, B. Z.; Yang, C. G.; Yang, G.; Ye, C. H.; Ye, J. B.; Ye, Q.; Yeh, S. C.; Yin, Z. W.; You, J. M.; Yunus, N.; Yzerman, M.; Zaccardelli, C.; Zaitsev, N.; Zemp, P.; Zeng, M.; Zeng, Y.; Zhang, D. H.; Zhang, Z. P.; Zhou, B.; Zhou, G. J.; Zhou, J. F.; Zhu, R. Y.; Zichichi, A.; van der Zwaan, B. C. C.; L3 Collaboration

    1993-11-01

    We report on inclusive xc production in Z decays reconstructed via the decay mode Xc → J + γ. This analysis is based on 1.1 million hadronic Z events. Interpreting the observed signal as Xcl, we obtain a branching ratio Br( Z→ Xcl + X) = (7.5±2.9(stat.) ±0.6(sys.)) × 10 -3. Assuming all events are produced in b decays we obtain Br( b→ Xcl + X) = (2.4 ± 0.9(stat.) ±0.2(sys.)) × 10 -2. We also present an improved measurement of the branching ratio Br(Z → J + X) = (3.6 ± 0.5 (stat.) ± 0.4 (sys.)) × 10 -3, obtained from dileptonic J decays.

  9. Keeping an Eye on Radioactivity

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    China sets up a national testing system for levels of radiation from various sources Radioactive iodine had been detected in the air above several regions of China,said China’s National Nuclear Emergency Coordination Committee on March 29.The regions include Heilongjiang

  10. Mass measurement of radioactive isotopes

    CERN Document Server

    Kluge, H J; Scheidenberger, C

    2004-01-01

    The highest precision in mass measurements on short-lived radionuclides is obtained using trapping and cooling techniques. Here, the experimental storage ring (ESR) at GSI/Darmstadt and the tandem Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN play an important role. Status and recent results on mass measurements of radioactive nuclides with ESR and ISOLTRAP are summarized.

  11. Radioactivity in Dutch consumer products

    CERN Document Server

    Janssen, M P M

    2002-01-01

    This study took place within the framework of a general update of the average radiation dose for the Dutch population. It focuses on consumer products in which radionuclides have been intentionally incorporated and on radiation-emitting devices that can be supplied to members of the public without special surveillance. Eleven consumer products were studied in more detail. The radiation from these products determined 90% of the total collective dose due to consumer products in the Netherlands in 1988. Individual and collective doses are presented here for each product. The total collective dose has decreased from 130 personSv in 1988 to 4.6 personSv at present. This reduction was attributed to: a decrease in the number of radioactive products (gas mantles), lower estimates of the number of radioactive products present in the Netherlands thanks to new information (camera lenses, smoke detectors containing Ra-226), replacement of radioactive by non-radioactive products (gas mantles, dental protheses), and a lowe...

  12. Indian programme on radioactive waste management

    Indian Academy of Sciences (India)

    P K Wattal

    2013-10-01

    The primary objective of radioactive waste management is protection of human health, environment and future generation. This article describes, briefly, the Indian programme on management of different radioactive wastes arising in the entire nuclear fuel cycle adhering to this objective.

  13. Purification of telluric acid for SNO+ neutrinoless double-beta decay search

    Energy Technology Data Exchange (ETDEWEB)

    Hans, S.; Rosero, R.; Hu, L. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Chkvorets, O. [Laurentian University, Sudbury (Canada); Chan, W.T.; Guan, S.; Beriguete, W. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Wright, A. [Queen University, Kingston (Canada); Ford, R. [SNOLAB, Creighton Mine, Sudbury (Canada); Chen, M.C. [Queen University, Kingston (Canada); Biller, S. [University of Oxford, Oxford OX1 3RH (United Kingdom); Yeh, M., E-mail: yeh@bnl.gov [Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2015-09-21

    Tellurium-130 has the highest natural abundance of any double-beta decay isotopes. Recently it has been developed as a promising candidate for loading in liquid scintillator to explore the Majorana or Dirac nature of the neutrino through a search for neutrinoless double beta decay (0νββ). To this end, procedures have been developed to transfer tellurium ions into the organic liquid by a water-based loading technology. However, traces of naturally occurring radioactivity and cosmic-ray induced isotopes introduced into the scintillator with tellurium could produce undesirable contaminations in the {sup 130}Te 0νββ region. Measurements using various elemental spikes prepared from different chemical forms indicate that the uses of self-scavenging as well as acid and thermal recrystallization prior to the preparation of a tellurium-loaded liquid scintillator can deplete U and Th and several cosmic-activated isotopes from Te feedstock by a factor of 10{sup 2}–10{sup 3} in a single pass. The process is also found to improve the optical transmission in the blue region, sensible to the photomultiplier tube, by removing traces of colored impurities. In addition to the scintillator-based experiments, this cleansing scheme has potential applications to the production of radiopure tellurium crystals for other rare-event experiments.

  14. Spot evolution on the red giant star XX Triangulum. A starspot-decay analysis based on time-series Doppler imaging

    CERN Document Server

    Künstler, A; Strassmeier, K G

    2015-01-01

    Solar spots appear to decay linearly proportional to their size. The decay rate of solar spots is directly related to magnetic diffusivity, which itself is a key quantity for the length of a magnetic-activity cycle. Is a linear spot decay also seen on other stars, and is this in agreement with the large range of solar and stellar activity cycle lengths? We investigate the evolution of starspots on the rapidly-rotating ($P_{\\rm rot}$ $\\approx$ 24 d) K0 giant XX Tri, using consecutive time-series Doppler images. Our aim is to obtain a well-sampled movie of the stellar surface over many years, and thereby detect and quantify a starspot decay law for further comparison with the Sun. We obtained continuous high-resolution and phase-resolved spectroscopy with the 1.2-m robotic STELLA telescope on Tenerife over six years. For each observing season, we obtained between 5 to 7 independent Doppler images, one per stellar rotation, making up a total of 36 maps. To quantify starspot area decay and growth, we match the ob...

  15. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    Energy Technology Data Exchange (ETDEWEB)

    Bullen, D.B.; Gdowski, G.E. (Science and Engineering Associates, Inc., Pleasanton, CA (USA)); Weiss, H. (Lawrence Livermore National Lab., CA (USA))

    1988-06-01

    Three copper-based alloys, CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni), are being considered along with three austenitic candidates as possible materials for fabrication of containers for disposal of high-level radioactive waste. The waste will include spent fuel assemblies from reactors as well as high-level reprocessing wastes in borosilicate glass and will be sent to the prospective repository at Yucca Mountain, Nevada, for disposal. The containers must maintain mechanical integrity for 50 yr after emplacement to allow for retrieval of waste during the preclosure phase of repository operation. Containment is required to be substantially complete for up to 300 to 1000 yr. During the early period, the containers will be exposed to high temperatures and high gamma radiation fields from the decay of high-level waste. The final closure joint will be critical to the integrity of the containers. This volume surveys the available data on the metallurgy of the copper-based candidate alloys and the welding techniques employed to join these materials. The focus of this volume is on the methods applicable to remote-handling procedures in a hot-cell environment with limited possibility of postweld heat treatment. The three copper-based candidates are ranked on the basis of the various closure techniques. On the basis of considerations regarding welding, the following ranking is proposed for the copper-based alloys: CDA 715 (best) > CDA 102 > CDA 613 (worst). 49 refs., 15 figs., 1 tab.

  16. Environmental aspects of commercial radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)

    1979-05-01

    Volume 2 contains chapters 6 through 10: environmental effects related to radioactive waste management associated with LWR fuel reprocessing - mixed-oxide fuel fabrication plant; environmental effects related to transporting radioactive wastes associated with LWR fuel reprocessing and fabrication; environmental effects related to radioactive waste management associated with LWR fuel reprocessing - retrievable waste storage facility; environmental effects related to geologic isolation of LWR fuel reprocessing wastes; and integrated systems for commercial radioactive waste management. (LK)

  17. Beta and muon decays

    Energy Technology Data Exchange (ETDEWEB)

    Galindo, A.; Pascual, P.

    1967-07-01

    These notes represent a series of lectures delivered by the authors in the Junta de Energia Nuclear, during the Spring term of 1965. They were devoted to graduate students interested in the Theory of Elementary Particles. Special emphasis was focussed into the computational problems. Chapter I is a review of basic principles (Dirac equation, transition probabilities, final state interactions.) which will be needed later. In Chapter II the four-fermion punctual Interaction is discussed, Chapter III is devoted to the study of beta-decay; the main emphasis is given to the deduction of the formulae corresponding to electron-antineutrino correlation, electron energy spectrum, lifetimes, asymmetry of electrons emitted from polarized nuclei, electron and neutrino polarization and time reversal invariance in beta decay. In Chapter IV we deal with the decay of polarized muons with radiative corrections. Chapter V is devoted to an introduction to C.V.C. theory. (Author)

  18. Suppressed Charmed B Decay

    Energy Technology Data Exchange (ETDEWEB)

    Snoek, Hella Leonie [Vrije Univ., Amsterdam (Netherlands)

    2009-06-02

    This thesis describes the measurement of the branching fractions of the suppressed charmed B0 → D*- a0+ decays and the non-resonant B0 → D*- ηπ+ decays in approximately 230 million Υ(4S) → B$\\bar{B}$ events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B0 → D*- a{sub 0}+ decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10-6. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle γ, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle γ can be performed using the decays of neutral B mesons. The B0 → D*- a0+ decay is sensitive to the angle γ and, in comparison to the current decays that are being employed, could significantly

  19. Holographic Glueball Decay

    CERN Document Server

    Brünner, Frederic; Rebhan, Anton

    2014-01-01

    We announce new results on glueball decay rates in the Sakai-Sugimoto model, a realization of holographic QCD from first principles that has only one coupling constant and an overall mass scale as free parameters. We extend a previous investigation by Hashimoto, Tan, and Terashima who have considered the lowest scalar glueball which arises from a somewhat exotic polarization of supergravity modes and whose mass is uncomfortably small in comparison with lattice results. On the other hand, the scalar glueball dual to the dilaton turns out to have a mass of about twice the mass of the rho meson (1487 MeV), very close to the scalar meson $f_0(1500)$ that is frequently interpreted as predominantly glue. Calculating the decay rate into two pions we find a surprisingly good agreement with experimental data for the $f_0(1500)$. We have also obtained decay widths for tensor and excited scalar glueballs, indicating universal narrowness.

  20. Decay spectroscopy of exotic fission products

    Science.gov (United States)

    Rykaczewski, Krzysztof

    2014-09-01

    The beta decay studies of exotic fission products have been performed at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory. The scientific program was focused on the beta-strength function measurements and resulting new half-lives and beta-delayed neutron properties. These observables are important for nuclear structure analysis and modeling of the nucleosynthesis within rapid neutron capture process. The highlights include ten new beta half-lives and several Pn branching ratios including an observation of beta-delayed two-neutron emitter 86Ga. In addition, the measurements of the beta-strength within beta-gamma emission window were performed using a Modular Total Absorption Spectrometer for 22 fission products. These MTAS results are also important for the analysis of reactor anti-neutrino anomaly. The beta decay studies of exotic fission products have been performed at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory. The scientific program was focused on the beta-strength function measurements and resulting new half-lives and beta-delayed neutron properties. These observables are important for nuclear structure analysis and modeling of the nucleosynthesis within rapid neutron capture process. The highlights include ten new beta half-lives and several Pn branching ratios including an observation of beta-delayed two-neutron emitter 86Ga. In addition, the measurements of the beta-strength within beta-gamma emission window were performed using a Modular Total Absorption Spectrometer for 22 fission products. These MTAS results are also important for the analysis of reactor anti-neutrino anomaly. Supported by the U.S. DOE Office of Nuclear Physics under Contracts DE-AC05-00R22725 (ORNL), DE-FG02-96ER40983 (UTK).

  1. Treatment of Radioactive Contaminated Soil and Concrete Wastes Using the Regulatory Clearance

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Il Sik; Ryu, W. S.; Kim, T. K.; Shon, J. S.; Ahn, S. J.; Lee, Y. H.; Bae, S. M.; Hong, D. S.; Ji, Y. Y.; Lee, B. C

    2008-11-15

    In the radioactive waste storage facilities at the Korea Atomic Energy Research Institute (KAERI) in Daejoen, there are thousands drums of radioactive contaminated soil and concrete wastes. The soil and concrete wastes were generated in 1988 during the decommissioning process of the research reactor and the attached radioactive waste treatment facility which were located in Seoul. The wastes were transported to Daejeon and have been stored since then. At the generation time, the radioactive contamination of the wastes was very low, and the radionuclides in the wastes was Co-60 and Cs-137. As the wastes have been stored for more than 20 years, the radioactivity concentration of the wastes has been decayed to become very extremely low. The wastes are needed to be treated because they take up large spaces at the storage facility. Also by treating the wastes, final disposal cost can be saved. So, the regulatory clearance was considered as a treatment method for the soil and concrete wastes with extremely low radioactivity concentration.

  2. Background radioactivity of construction materials, raw substance and ready-made CaMoO4 crystals

    Directory of Open Access Journals (Sweden)

    Busanov O.A.

    2014-01-01

    Full Text Available The results of measurements of natural radioactive isotopes content in different source materials of natural and enriched composition used for CaMoO4 scintillation crystal growing are presented. The crystals are to be used in the experiment to search for neutrinoless double beta decay of 100Mo.

  3. Background radioactivity of construction materials, raw substance and ready-made CaMoO4 crystals

    CERN Document Server

    Busanov, O A; Gavriljuk, Yu M; Gezhaev, A M; Kazalov, V V; Kornoukhov, V N; Kuzminov, V V; Moseev, P S; Panasenko, S I; Ratkevich, S S; Yakimenko, S P

    2013-01-01

    The results of measurements of natural radioactive isotopes content in different source materials of natural and enriched composition used for CaMoO4 scintillation crystal growing are presented. The crystals are to be used in the experiment to search for double neutrinoless betas-decay of Mo-100.

  4. 46 CFR 147.100 - Radioactive materials.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Radioactive materials. 147.100 Section 147.100 Shipping... Stowage and Other Special Requirements for Particular Materials § 147.100 Radioactive materials. (a) Radioactive materials must not be brought on board, used in any manner, or stored on the vessel, unless...

  5. 49 CFR 175.705 - Radioactive contamination.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Radioactive contamination. 175.705 Section 175.705... Regulations Applicable According to Classification of Material § 175.705 Radioactive contamination. (a) A... (radioactive) materials that may have been released from their packagings. (b) When contamination is present...

  6. Transmutation of radioactive nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Toor, A; Buck, R

    2000-03-15

    years. One approach to the RNW storage problem has been to transmute the radioactive elements into other radioactive isotopes with much shorter half-lives. Transmutation of both RNW components using neutrons has been discussed and studied over the past four decades. Most transmutation studies have examined the feasibility of using neutron-induced reactions where the neutrons would be provided by accelerator-based spallation neutron sources, tokamak fusion reactors, sub-critical fission reactors and other novel concepts. Studies have shown that all proposed transmutation processes to treat RNW using neutron reactions are deficient or marginal at best from the point of view of energy consumption and/or cost. We suggest an alternative approach that has not been considered to date: the transmutation of RNW elements using high-energy photons or gamma rays. The photo-disintegration of RNW may provide an effective way to treat reprocessed waste; waste that has been chemically separated or the residual waste left over after neutron processing. Photo-disintegration is attractive in that any isotope can be transmuted. This approach is now potentially practical because of the development of micropole undulators (MPUs) that allow us to use small storage rings to economically generate photons with gamma-ray energies and to tune these ''gamma rays'' to the peak of the cross-section resonance for various RNW elements. Because the cross sections for all RNW nuclei have a broad peak with the maximum in the 12-18 MeV range, a single MPU could be used to treat both actinide and fission fragment components of RNW. The goal of this study is to make estimates of the reaction rates and energy efficiency of the transmutation of typical RNW elements using gamma rays to establish whether or not gamma-ray transmutation should be examined as a viable alternative solution to RNW warranting further study.

  7. Flavor changing nucleon decay

    Science.gov (United States)

    Maekawa, Nobuhiro; Muramatsu, Yu

    2017-04-01

    Recent discovery of neutrino large mixings implies the large mixings in the diagonalizing matrices of 5 bar fields in SU (5) grand unified theory (GUT), while the diagonalizing matrices of 10 fields of SU (5) are expected to have small mixings like Cabibbo-Kobayashi-Maskawa matrix. We calculate the predictions of flavor changing nucleon decays (FCND) in SU (5), SO (10), and E6 GUT models which have the above features for mixings. We found that FCND can be the main decay mode and play an important role to test GUT models.

  8. Measurement of radioactive contamination in the high-resistivity silicon CCDs of the DAMIC experiment

    CERN Document Server

    Aguilar-Arevalo, A; Bertou, X; Bole, D; Butner, M; Cancelo, G; Vázquez, A Castañeda; Chavarria, A E; Neto, J R T de Mello; Dixon, S; D'Olivo, J C; Estrada, J; Moroni, G Fernandez; Torres, K P Hernández; Izraelevitch, F; Kavner, A; Kilminster, B; Lawson, I; Liao, J; López, M; Molina, J; Moreno-Granados, G; Pena, J; Privitera, P; Sarkis, Y; Scarpine, V; Schwarz, T; Haro, M Sofo; Tiffenberg, J; Machado, D Torres; Trillaud, F; You, X; Zhou, J

    2015-01-01

    We present measurements of radioactive contamination in the high-resistivity silicon charge-coupled devices (CCDs) used by the DAMIC experiment to search for dark matter particles. Novel analysis methods, which exploit the unique spatial resolution of CCDs, were developed to identify $\\alpha$ and $\\beta$ particles. Uranium and thorium contamination in the CCD bulk was measured through $\\alpha$ spectroscopy, with an upper limit on the $^{238}$U ($^{232}$Th) decay rate of 5 (15) kg$^{-1}$ d$^{-1}$ at 95% CL. We also searched for pairs of spatially correlated electron tracks separated in time by up to tens of days, as expected from $^{32}$Si-$^{32}$P or $^{210}$Pb-$^{210}$Bi sequences of $\\beta$ decays. The decay rate of $^{32}$Si was found to be $80^{+110}_{-65}$ kg$^{-1}$ d$^{-1}$ (95% CI). An upper limit of $\\sim$35 kg$^{-1}$ d$^{-1}$ (95% CL) on the $^{210}$Pb decay rate was obtained independently by $\\alpha$ spectroscopy and the $\\beta$ decay sequence search. These levels of radioactive contamination are su...

  9. Subsides for optimization of transfer of radioactive liquid waste from {sup 99}MO production plant to the waste treatment facility

    Energy Technology Data Exchange (ETDEWEB)

    Rego, Maria Eugenia de Melo; Vicente, Roberto; Hiromoto, Goro, E-mail: maria.eugenia@ipen.br, E-mail: rvicente@ipen.br, E-mail: hiromoto@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The increasing need for radioisotopes lead Brazil to consider the domestic production of {sup 99}Mo from fission of low enriched uranium targets. In order to meet the present demand of {sup 99m}Tc generators the planned 'end of irradiation' activity of {sup 99}Mo is about 170 TBq per week. The radioactive waste from the production plant will be transferred to a waste treatment facility at the same site. The total activity of the actinides, fission and activation products present in the waste were predicted based on the fission yield and activation data for the irradiation conditions, such as composition and mass of uranium targets, irradiation time, neutron flux, production process and schedule, already established by the project management. The transfer of the waste from the production plant to the treatment facility will be done by means of special shielded packages. In the present study, the commercially available code Scale 6.0 was used to simulate the irradiation of the targets and the decay of radioactive products, assuming that an alkaline dissolution process would be performed on the targets before the removal and purification of {sup 99}Mo. The assessment of the shielding required for the packages containing liquid waste was done using MicroShield 9 code. The results presented here are part of a project that aims at contributing to the design of the waste management system for the {sup 99}Mo production facility. (author)

  10. Ethanol separation from ethanol-water solution by ultrasonic atomization and its proposed mechanism based on parametric decay instability of capillary wave

    Science.gov (United States)

    Sato, Masanori; Matsuura, Kazuo; Fujii, Toshitaka

    2001-02-01

    We show the experimental data of selective ethanol separation from ethanol-water solution, using ultrasonic atomization. Pure ethanol could be obtained directly from a solution with several mol% ethanol-water solution at 10 °C. This result can be explained in terms of parametric decay instability of capillary wave, in which high localization and accumulation of acoustic energy occur, leading to ultrasonic atomization. That is, parametric decay instability condenses the energy of longitudinal waves in a highly localized surface area of the capillary wave, and causes ultrasonic atomization.

  11. The formation and decay of superheavy nuclei produced in sup 4 sup 8 Ca-induced reactions

    CERN Document Server

    Kumar, S; Gupta, R K; Münzenberg, G; Scheid, W

    2003-01-01

    The formation of superheavy nuclei in sup 4 sup 8 Ca+ sup 2 sup 3 sup 2 Th, sup 2 sup 3 sup 8 U, sup 2 sup 4 sup 2 sup , sup 2 sup 4 sup 4 Pu and sup 2 sup 4 sup 8 Cm reactions and their subsequent decay are studied within the quantum mechanical fragmentation theory (QMFT) and the QMFT-based preformed cluster decay model (PCM) of Gupta and collaborators. According to QMFT, all these sup 4 sup 8 Ca-induced reactions are cold fusion reactions with relative excitation energies larger than those for the Pb-induced cold fusion reactions and smaller than those for the lighter beam, i.e. Mg, Si or S-induced hot fusion reactions. The same reactions were first suggested by Gupta et al in 1977 on the basis of QMFT, and this study re-establishes the same result. In fact, for such heavy isotopes of Z = 110 to 116, sup 5 sup 0 Ca is shown to be a better beam for cold fusion, but sup 5 sup 0 Ca is a radioactive nucleus. The alpha-decay half-lives of these nuclei after 3n and/or 4n evaporations, i.e. of the evaporation resi...

  12. Characterization of Aged Radioactive Pollucite

    Energy Technology Data Exchange (ETDEWEB)

    Fortner, Jeffrey [Argonne National Lab. (ANL), Argonne, IL (United States); Kropf, A. Jeremy [Argonne National Lab. (ANL), Argonne, IL (United States); Kaminski, Michael [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-01

    The objective of this task was to provide information to better understand the long-term effects of decay on the stability of crystalline pollucite (CsAlSi2O6, also known as Cs-leucite). This decay is a key scientific issue in the assessment of the long-term stability, and hence performance, of pollucite as a waste form for 137Cs. Most previous work on radiation effects in waste forms focused on alpha radiation, which produces more displacements per decay than beta radiation. However, the results of decay with beta radiation, which changes both the ionic radius and the valence of the element undergoing decay (0.160 nm for Ba2+ vs. 0.188 nm for Cs+), are likely to predominate over cascade damage. The resulting changes in coordination chemistry may destabilize the waste form, permitting release of radionuclides to the accessible environment.

  13. Leptonic Decays of Charged Pseudoscalar Mesons - 2015

    Energy Technology Data Exchange (ETDEWEB)

    Rosner, Jonathan L. [Chicago U., EFI; Stone, Sheldon [Syracuse U.; Van de Water, Ruth S. [Fermilab

    2015-09-07

    We review the physics of purely leptonic decays of $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of the constituent quarks and a strong interaction parameter related to the overlap of the quark and antiquark wave-functions in the meson, called the decay constant $f_P$. The leptonic decay constants for $\\pi^\\pm$, $K^\\pm$, $D^{\\pm}$, $D_s^\\pm$, and $B^\\pm$ mesons can be obtained with controlled theoretical uncertainties and high precision from {\\it ab initio} lattice-QCD simulations. The combination of experimental leptonic decay-rate measurements and theoretical decay-constant calculations enables the determination of several elements of the CKM matrix within the standard model. These determinations are competitive with those obtained from semileptonic decays, and also complementary because they are sensitive to different quark flavor-changing currents. They can also be used to test the unitarity of the first and second rows of the CKM matrix. Conversely, taking the CKM elements predicted by unitarity, one can infer "experimental" values for $f_P$ that can be compared with theory. These provide tests of lattice-QCD methods, provided new-physics contributions to leptonic decays are negligible at the current level of precision. This review is the basis of the article in the Particle Data Group's 2016 edition, updating the versions in Refs. [1-3].

  14. Cluster radioactivity and very asymmetric fission through quasi-molecular shapes

    Energy Technology Data Exchange (ETDEWEB)

    Royer, G. [Centre National de la Recherche Scientifique, 44 - Nantes (France). Lab. de Physique Subatomique et des Technologies Associees; Gupta, R.K. [Panjab Univ., Chandigarh (India). Dept. of Physics; Denisov, V.Yu. [Akademyiya Nauk Ukrayini, Kiev (Ukraine)

    1997-12-31

    The decay of radioactive nuclei which emit heavy clusters like C, O, Ne, Mg and Si has been studied in the fission valley which leads one spherical nucleus towards two spherical touching nuclei before crossing the barrier. Assuming volume conservation, the deformation energy has been calculated within a generalized liquid drop model taking into account the proximity effects between the cluster and the daughter nucleus. The theoretical partial half-lives obtained within the WKB barrier penetration probability are in good agreement with the experimental data for the heaviest clusters. The Ne, Mg and Si emission looks like a very-asymmetric spontaneous fission. The {sup 14}C radioactivity is not correctly described within the fission hypothesis. The {sup 14}C and apparently also the {sup 20}O are probably pre-born in the parent nucleus, the emission being similar to the {alpha} decay process. (author). 27 refs.

  15. Analysis of Experiments Exhibiting Time-Varying Nuclear Decay Rates: Systematic Effects or New Physics?

    CERN Document Server

    Jenkins, Jere H; Sturrock, Peter A; Mundy, Daniel W

    2011-01-01

    Since the 1930s, and with very few exceptions, it has been assumed that the process of radioactive decay is a random process, unaffected by the environment in which the decaying nucleus resides. There have been instances within the past few decades, however, where changes in the chemical environment or physical environment brought about small changes in the decay rates. But even in light of these instances, decaying nuclei that were undisturbed or un-"pressured" were thought to behave in the expected random way, subject to the normal decay probabilities which are specific to each nuclide. Moreover, any "non-random" behavior was assumed automatically to be the fault of the detection systems, the environment surrounding the detectors, or changes in the background radiation to which the detector was exposed. Recently, however, evidence has emerged from a variety of sources, including measurements taken by independent groups at Brookhaven National Laboratory, Physikalisch-Technische Bundesanstalt, and Purdue Univ...

  16. The safe transport of radioactive materials

    CERN Document Server

    Gibson, R

    1966-01-01

    The Safe Transport of Radioactive Materials is a handbook that details the safety guidelines in transporting radioactive materials. The title covers the various regulations and policies, along with the safety measures and procedures of radioactive material transport. The text first details the 1963 version of the IAEA regulation for the safe transport of radioactive materials; the regulation covers the classification of radionuclides for transport purposes and the control of external radiation hazards during the transport of radioactive materials. The next chapter deals with concerns in the im

  17. Unified description of the proton, alpha, cluster decays and spontaneously fissions half- life

    CERN Document Server

    Mavrodiev, Strachimir Cht

    2016-01-01

    Some time ago the possibility of classical (without Gamow tunneling) universal description of radioactive nuclei decay was demonstrated. Such possibility is basis on the classical interpretation of Bohmian Psi-field reality in Bohmian-Chetaev mechanics and the hypothesis for the presence of dissipative forces, generated from the Gryzinski translational precession of the charged particles spin, in Langevin- Kramers diffusion mechanism. In this paper is present an unified model of proton, alpha decay, cluster radioactivity and spontaneous fission half-life as explicit function which depends on the total decay energy and kinetic energy, the number of protons and neutrons of daughter product, the number of protons and neutrons of mother nuclei and from a set) unknown digital parameters. The Half- lifes of the 573 nuclei taken from NuDat database together with the recent experimental data from Oganessian provide a basis for discovering the explicit form of the Kramers solution of Langevin type equation in a framew...

  18. Error-landscape-based multi-objective calibration of the Smagorinsky eddy-viscosity using high-Reynolds-number decaying turbulence data

    NARCIS (Netherlands)

    Meyers, Johan; Meneveau, Charles; Geurts, Bernard J.

    2010-01-01

    A suite of large-eddy simulation(LESs) of decaying homogeneous isotropic turbulence at high Reynolds numbers is performed and compared to wind-tunnel experiments in the tradition of Comte-Bellot and Corrsin. The error-landscape approach is used for the evaluation of the Smagorinsky model, and the re

  19. Systematic Study of Trace Radioactive Impurities in Candidate Construction Materials for EXO-200

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, D.S.; Grinberg, P.; Weber, P.; Baussan, E.; Djurcic, Z.; Keefer, G.; Piepke, A.; Pocar, A.; Vuilleumier, J.-L.; Vuilleumier, J.-M.; Akimov, D.; Bellerive, A.; Bowcock, M.; Breidenbach, M.; Burenkov, A.; Conley, R.; Craddock, W.; Danilov, M.; DeVoe, R.; Dixit, M.; Dolgolenko, A.; /Alabama U. /NRC-INMS /Neuchatel U. /Stanford U., Phys. Dept. /SLAC /Colorado State U. /Laurentian U. /Maryland U. /UC, Irvine

    2007-10-24

    The Enriched Xenon Observatory (EXO) will search for double beta decays of 136Xe. We report the results of a systematic study of trace concentrations of radioactive impurities in a wide range of raw materials and finished parts considered for use in the construction of EXO-200, the first stage of the EXO experimental program. Analysis techniques employed, and described here, include direct gamma counting, alpha counting, neutron activation analysis, and high-sensitivity mass spectrometry.

  20. Discussions about whether radioactive half life can be changed by mechanic motion

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this essay, some discussions and comments about the paper entitled "Can the decay rate of 32P be changed by mechanic motion?" (Ding et al., Science in China Series B:Chemistry (Chinese version), 2008, 38(11):1035-1037) are given. It was strongly suggested that its experimental methods, data calculations and conclusion should be reconsidered. After the data were recalculated, the new results supported that the chiral mechanic motion could induce the changes of radioactive half life.

  1. Activity Concentration Monitoring for Alpha Radioactive Aerosol in CRARL after Reprocessing Experiments

    Institute of Scientific and Technical Information of China (English)

    WANG; Xiang-li; LIU; Ning; WANG; Xiao-rong; BAI; Yang; JIAO; Xiao-yan; XU; Xin; MA; Hao-ran

    2015-01-01

    The activity concentration for alpha radioactive aerosol in CRARL after reprocessing experiments was analyzed.Through the decay method of activity concentration monitoring,the processed result shows the background is 3.05×10-3 s-1,σ(0)=2.25×10-3,LC=2.33×10-3 Bq/m3,LD=4.66×10-3 Bq/m3.The result indicated

  2. Radioactivity: conception to birth. The Health Physics Society 1995 Radiology Centennial Hartman Oration.

    Science.gov (United States)

    Frame, P W

    1996-05-01

    Röntgen's description of his discovery of x rays was convincing and comprehensive. The response of the scientific community and public was immediate and intense. In contrast, the discovery of radioactivity was a muddled affair that excited little interest. While it would prove far more revolutionary than that of x rays, the discovery of radioactivity began, in the words of Alfred Romer, as something of a dead horse. There it lay, too big to ignore, but what did you do with it? Even the discoverer, Henri Becquerel, left it to decay and went on to pursue other interests. For various reasons, others chose to investigate: Marie and Pierre Curie in France, William Crookes in England, and Ernest Rutherford in Canada. But it was Frederick Soddy, a young chemist with a fascination for alchemy, who, together with Rutherford, revealed the true nature of radioactivity: transmutation.

  3. Laboratory measurement of radioactivity purification for 212Pb in liquid scintillator

    Science.gov (United States)

    Hu, Wei; Fang, Jian; Yu, Bo-Xiang; Zhang, Xuan; Zhou, Li; Cai, Xiao; Sun, Li-Jun; Liu, Wan-Jin; Wang, Lan; Lü, Jun-Guang

    2016-09-01

    Liquid scintillator (LS) has been widely used in past and running neutrino experiments, and is expected also to be used in future experiments. Requirements on LS radio-purity have become higher and higher. Water extraction is a powerful method to remove soluble radioactive nuclei, and a mini-extraction station has been constructed. To evaluate the extraction efficiency and optimize the operation parameters, a setup to load radioactivity to LS and a laboratory scale setup to measure radioactivity using the 212Bi-212Po-208Pb cascade decay have been developed. Experience from this laboratory study will be useful for the design of large scale water extraction plants and the optimization of working conditions in the future. Supported by The Strategic Priority Research Program of the Chinese Academy of Sciences (XDA10010500), Natural Science Foundation of China (11390384)

  4. IRACM : A code system to calculate induced radioactivity produced by ions and neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Susumu; Fukuda, Mitsuhiro; Nishimura, Koichi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Watanabe, Hiromasa; Yamano, Naoki

    1997-05-01

    It is essential to estimate of radioactivity induced in accelerator components and samples bombarded by energetic ion beams and the secondary neutrons of high-energy accelerator facilities in order to reduce the amount of radioactive wastes and to minimize radiation exposure to personnel. A computer code system IRACM has been developed to estimate product nuclides and induced radioactivity in various radiation environments of accelerator facilities. Nuclide transmutation with incident particles of neutron, proton, deuteron, alpha, {sup 12}C, {sup 14}N, {sup 16}O, {sup 20}Ne and {sup 40}Ar can be computed for arbitrary multi-layer target system in a one-dimensional geometry. The code system consists of calculation modules and libraries including activation cross sections, decay data and photon emission data. The system can be executed in both FACOM-M780 mainframe and DEC workstations. (author)

  5. Annual Report of Airborne Discharge Station for Treated Radioactive Waste Water with Tritium in 2015

    Institute of Scientific and Technical Information of China (English)

    HAN; Yi-dan; FENG; Chun-xiao; LONG; Bo-kang; ZHAO; Yu-hang; WANG; Jian-xin

    2015-01-01

    The airborne discharge station for radioactive purity liquid waste water is officially put into operation in 2010,and it is the first facility for treated radioactive waste water with tritium in China.The station is primarily based on the"air humidification"principle for treated waste water

  6. Practical Work Using Low-Level Radioactive Materials Available to the Public

    Science.gov (United States)

    Whitcher, Ralph

    2011-01-01

    These notes describe six practical activities for supplementing standard practical work in radioactivity. They are based on a series of workshops given at ASE regional and national conferences by the ASE's Safeguards in Science Committee. The activities, which demonstrate aspects of radioactivity, feature consumer items that happen to be…

  7. Radioactive waste management in Austria

    Directory of Open Access Journals (Sweden)

    Neubauer Josef

    2004-01-01

    Full Text Available At the Austrian Research Centers Seibersdorf, there are several facilities in stalled for treatment of waste of low and intermediate radioactivity level (radwaste. A separate company within Centers, Nuclear Engineering Seibersdorf, has been formed recently, acting as a centralized facility for treatment, conditioning and storing of such waste within the country. The relevant treatment technology is applied depending on the waste category. In total about 6900 m3 of solid waste of low and intermediate radioactivity level originating from Austria was treated in the period between 1976 and 2002. Presently, there exists no final repository for radwaste in Austria. A study is under way to identify the structure for a long term storage facility.

  8. Cluster Radioactivity in 127I

    Directory of Open Access Journals (Sweden)

    K. Manimaran

    2013-08-01

    Full Text Available Using the preformation cluster model of Gupta and collaborators we have studied all the possible cluster decay modes of 127 I. The calculated half-lives are compared with recently measured lower limits of cluster decay half-lives (for the clusters like 24Ne, 28Mg, 30Mg, 32Si, 34Si, 48Ca and 49Sc of 127I. Our calculated half-life values lies well above the experimentally measured lower limits and the trend of the values also matches with experimental ones.

  9. Radioactive Waste Management BasisApril 2006

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, B K

    2011-08-31

    This Radioactive Waste Management Basis (RWMB) documents radioactive waste management practices adopted at Lawrence Livermore National Laboratory (LLNL) pursuant to Department of Energy (DOE) Order 435.1, Radioactive Waste Management. The purpose of this Radioactive Waste Management Basis is to describe the systematic approach for planning, executing, and evaluating the management of radioactive waste at LLNL. The implementation of this document will ensure that waste management activities at LLNL are conducted in compliance with the requirements of DOE Order 435.1, Radioactive Waste Management, and the Implementation Guide for DOE Manual 435.1-1, Radioactive Waste Management Manual. Technical justification is provided where methods for meeting the requirements of DOE Order 435.1 deviate from the DOE Manual 435.1-1 and Implementation Guide.

  10. Recent advances in β-decay spectroscopy at CARIBU

    Directory of Open Access Journals (Sweden)

    Mitchell A. J.

    2016-01-01

    Full Text Available β-decay spectroscopy of nuclei far from stability can provide powerful insight into a broad variety of topics in nuclear science, ranging from exotic nuclear structure phenomena, stellar nucleosynthesis processes, and applied topics such as quantifying “decay heat” discrepancies for advanced nuclear fuel cycles. Neutronrich nuclei approaching the drip-line are difficult to access experimentally, leaving many key examples largely under studied. The CARIBU radioactive beam facility at Argonne National Laboratory exploits spontaneous fission of 252Cf in production of such beams. The X-Array and SATURN decay station have been commissioned to perform detailed decay spectroscopy of low-energy CARIBU beams. An extended science campaign was started during 2015; with projects investigating nuclear shape changes, collective octupole vibrations, β-delayed neutron emission, and decay-scheme properties which could explain the reactor antineutrino puzzle. In this article we review the current status of the setup, update on the first results and recent hardware upgrades, and look forward to future possibilities.

  11. Recent advances in β-decay spectroscopy at CARIBU

    Science.gov (United States)

    Mitchell, A. J.; Copp, P.; Savard, G.; Lister, C. J.; Lane, G. J.; Carpenter, M. P.; Clark, J. A.; Zhu, S.; Ayangeakaa, A. D.; Bottoni, S.; Brown, T. B.; Chowdhury, P.; Chillery, T. W.; David, H. M.; Hartley, D. J.; Heckmaier, E.; Janssens, R. V. F.; Kolos, K.; Kondev, F. G.; Lauritsen, T.; McCutchan, E. A.; Norman, E. B.; Padgett, S.; Scielzo, N. D.; Seweryniak, D.; Smith, M. L.; Wilson, G. L.

    2016-09-01

    β-decay spectroscopy of nuclei far from stability can provide powerful insight into a broad variety of topics in nuclear science, ranging from exotic nuclear structure phenomena, stellar nucleosynthesis processes, and applied topics such as quantifying "decay heat" discrepancies for advanced nuclear fuel cycles. Neutronrich nuclei approaching the drip-line are difficult to access experimentally, leaving many key examples largely under studied. The CARIBU radioactive beam facility at Argonne National Laboratory exploits spontaneous fission of 252Cf in production of such beams. The X-Array and SATURN decay station have been commissioned to perform detailed decay spectroscopy of low-energy CARIBU beams. An extended science campaign was started during 2015; with projects investigating nuclear shape changes, collective octupole vibrations, β-delayed neutron emission, and decay-scheme properties which could explain the reactor antineutrino puzzle. In this article we review the current status of the setup, update on the first results and recent hardware upgrades, and look forward to future possibilities.

  12. HMPT: Basic Radioactive Material Transportation

    Energy Technology Data Exchange (ETDEWEB)

    Hypes, Philip A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-29

    Hazardous Materials and Packaging and Transportation (HMPT): Basic Radioactive Material Transportation Live (#30462, suggested one time) and Test (#30463, required initially and every 36 months) address the Department of Transportation’s (DOT’s) function-specific [required for hazardous material (HAZMAT) handlers, packagers, and shippers] training requirements of the HMPT Los Alamos National Laboratory (LANL) Labwide training. This course meets the requirements of 49 CFR 172, Subpart H, Section 172.704(a)(ii), Function-Specific Training.

  13. Clays in radioactive waste disposal

    OpenAIRE

    Delage, Pierre; Cui, Yu-Jun; Tang, Anh-Minh

    2010-01-01

    Clays and argillites are considered in some countries as possible host rocks for nuclear waste disposal at great depth. The use of compacted swelling clays as engineered barriers is also considered within the framework of the multi-barrier concept. In relation to these concepts, various research programs have been conducted to assess the thermo-hydro-mechanical properties of radioactive waste disposal at great depth. After introducing the concepts of waste isolation developed in Belgium, Fran...

  14. Analysis methods for airborne radioactivity

    OpenAIRE

    Ala-Heikkilä, Jarmo J

    2008-01-01

    High-resolution gamma-ray spectrometry is an analysis method well suitable for monitoring airborne radioactivity. Many of the natural radionuclides and a majority of anthropogenic nuclides are prominent gamma-ray emitters. With gamma-ray spectrometry different radionuclides are readily observed at minute concentrations that are far from health hazards. The gamma-ray spectrometric analyses applied in air monitoring programmes can be divided into particulate measurements and gas measurements. I...

  15. Summary of national and international fuel cycle and radioactive waste management programs, 1984

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, K.M.; Lakey, L.T.; Leigh, I.W.

    1984-07-01

    Worldwide activities related to nuclear fuel cycle and radioactive waste management programs are summarized. Several trends have developed in waste management strategy: All countries having to dispose of reprocessing wastes plan on conversion of the high-level waste (HLW) stream to a borosilicate glass and eventual emplacement of the glass logs, suitably packaged, in a deep geologic repository. Countries that must deal with plutonium-contaminated waste emphasize pluonium recovery, volume reduction and fixation in cement or bitumen in their treatment plans and expect to use deep geologic repositories for final disposal. Commercially available, classical engineering processing are being used worldwide to treat and immobilize low- and intermediate-level wastes (LLW, ILW); disposal to surface structures, shallow-land burial and deep-underground repositories, such as played-out mines, is being done widely with no obvious technical problems. Many countries have established extensive programs to prepare for construction and operation of geologic repositories. Geologic media being studied fall into three main classes: argillites (clay or shale); crystalline rock (granite, basalt, gneiss or gabbro); and evaporates (salt formations). Most nations plan to allow 30 years or longer between discharge of fuel from the reactor and emplacement of HLW or spent fuel is a repository to permit thermal and radioactive decay. Most repository designs are based on the mined-gallery concept, placing waste or spent fuel packages into shallow holes in the floor of the gallery. Many countries have established extensive and costly programs of site evaluation, repository development and safety assessment. Two other waste management problems are the subject of major R and D programs in several countries: stabilization of uranium mill tailing piles; and immobilization or disposal of contaminated nuclear facilities, namely reactors, fuel cycle plants and R and D laboratories.

  16. Radioactive materials transport accident analysis

    Energy Technology Data Exchange (ETDEWEB)

    McSweeney, T.I.; Maheras, S.J.; Ross, S.B. [Battelle Memorial Inst. (United States)

    2004-07-01

    Over the last 25 years, one of the major issues raised regarding radioactive material transportation has been the risk of severe accidents. While numerous studies have shown that traffic fatalities dominate the risk, modeling the risk of severe accidents has remained one of the most difficult analysis problems. This paper will show how models that were developed for nuclear spent fuel transport accident analysis can be adopted to obtain estimates of release fractions for other types of radioactive material such as vitrified highlevel radioactive waste. The paper will also show how some experimental results from fire experiments involving low level waste packaging can be used in modeling transport accident analysis with this waste form. The results of the analysis enable an analyst to clearly show the differences in the release fractions as a function of accident severity. The paper will also show that by placing the data in a database such as ACCESS trademark, it is possible to obtain risk measures for transporting the waste forms along proposed routes from the generator site to potential final disposal sites.

  17. Some topics on charmonium decays at BESⅢ experiment

    Institute of Scientific and Technical Information of China (English)

    CHEN nai-Xuan

    2008-01-01

    The construction of BESⅢ detector has been finished and the data taking is under plan. Some physics topics on charmonium decays at BESⅢ experiment are discussed in this paper. The measurement of properties of ηc and η'c at BESⅢ is discussed and the expected precision of the measurement is estimated based on BOSS. Also the XcJ decay and the measurement of hyperon decay parameters are mentioned.

  18. Rare B decays at LEP

    CERN Document Server

    Kluit, P M

    2001-01-01

    The results of the LEP experiments for rare B decays will be reviewed, covering hadronic final states, radiative and other rare decays and results for the inclusive charmless branching ratio. (8 refs).

  19. Technical report on treatment of radioactive slurry liquid waste

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Gyeong Hwan; Jo, Eun Sung; Park, Seung Kook; Jung, Ki Jung

    1999-06-01

    By literature survey, this report deals with the technology on typical pre-treatment and filtration of radioactive slurry liquid waste, produced during the operation of TRIGA Mark-II, III research reactor, and produced during the decommission/decontamination of TRIGA Mark-II, III research reactor. It is reviewed pre-treatment procedure, both physical and chemical that optimise the dewatering characteristics, and also surveyed types of dewatering devices based on centrifuges, vacuum and pressure filters with particular reference to various combined field approaches using two or more complementary driving forces to achieve better performance. Dewatering operations and devises on filtration of radioactive slurry liquid waste are also analysed. (author)

  20. Radiation safety in sea transport of radioactive material in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Odano, N. [National Maritime Research Inst., Tokyo (Japan); Yanagi, H. [Nuclear Fuel Transport Co., Ltd., Tokyo (Japan)

    2004-07-01

    Radiation safety for sea transport of radioactive material in Japan has been discussed based on records of the exposed dose of sea transport workers and measured data of dose rate equivalents distribution inboard exclusive radioactive material shipping vessels. Recent surveyed records of the exposed doses of workers who engaged in sea transport operation indicate that exposed doses of transport workers are significantly low. Measured distribution of the exposed dose equivalents inboard those vessels indicates that dose rate equivalents inside those vessels are lower than levels regulated by the transport regulations of Japan. These facts clarify that radiation safety of inboard environment and handling of transport casks in sea transport of radioactive material in Japan are assured.

  1. CP-violations in decays

    Indian Academy of Sciences (India)

    Y Sakai

    2006-11-01

    Recent results on CP-violation measurements in decays from energy asymmetric -factory experiments are reported. Thanks to large accumulated data samples, CP-violations in decays in mixing-decay interference and direct CP-violation are now firmly established. The measurements of three angles of the unitarity triangle from CP-violations of decays are quite consistent with the Standard Model expectations. These results strongly support the validity of the Kobayashi-Maskawa prescription of CP-violation.

  2. Decay law of allowed and forbidden transitions inβ--decay half-lives%β-衰变中容许跃迁和禁戒跃迁的衰变规律∗

    Institute of Scientific and Technical Information of China (English)

    张绍庆; 谢娟; 张小平; 支启军

    2016-01-01

    β-decay half-lives are not only important parameters for studying the structures and decay properties of the exotic nucleus far from stability, but also basic parameters for understanding the astrophysical phenomenon. Astrophysicists need exact data ofβ-decay half-lives as input to build nucleosynthesis models for understanding the elements abundances of our universe and solar system. For nuclei far from stability, experimental synthesis and further measurements on their half-lives are rather difficult due to the rarity and radioactivity of target material for synthesizing these nuclei. In theoretical respect, although there are many models such as finite-range droplet model plus quasi-particle random-phase approximation (QRPA), microscopic density functional theory plus QRPA, Hatree-Fock-Bogoliubov theory plus QRPA, and shell model etc., it is still a challenge to calculate β-decay half-lives in a reliable way for nuclei far from the β-stable line, partly because of the intrinsic complexity of nuclear multi-body problem. In empirical respect, Sargent made an empirical study of β-decay half-lives in 1933 and discovered a law which is consistent with the Fermi β-decay theory proposed one year later. From then on, there have been a few parametric models based on some of real physical behaviors, which describe complex quantum many-body systems, such as the Kratz–Herrmann formula and the gross theory. Recently, Zhang et al. discovered an exponential law describing β-decay half-lives and the nucleon number (Z, N ) of parent nuclei far from the stable line. A formula is proposed to calculate the β-decay half-lives of nuclei far from stability, which can describe experimental data reasonably well. However, the differences between allowed transitions and forbidden transitions are not fully considered in this formula. Zhang et al. used a set of parameters to describe both allowed transitions and forbidden transitions. In this paper, we consider the different β-decay

  3. DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

    Energy Technology Data Exchange (ETDEWEB)

    NA

    2004-11-22

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) important to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are in the form of tabulated functions with pH and log (line integral) CO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. The output data from this report are fundamental inputs for Total System Performance Assessment for the License Application (TSPA-LA) to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for all of the actinides. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise addressed.

  4. Accelerated radioactive nuclear beams: Existing and planned facilities

    Energy Technology Data Exchange (ETDEWEB)

    Nitschke, J.M.

    1992-07-01

    An over-view of existing and planned radioactive nuclear beam facilities world-wide. Two types of production methods are distinguished: projectile fragmentation and the on-line isotope separator (ISOL) method. While most of the projectile fragmentation facilities are already in operation, almost all the ISOL-based facilities are in still the planning stage.

  5. Wien filter for cooled low-energy radioactive ion beams

    NARCIS (Netherlands)

    Nummela, S; Dendooven, P; Heikkinen, P; Huikari, J; Nieminen, A; Jokinen, A; Rinta-Antila, S; Rubchenya, V.; Aysto, J

    2002-01-01

    A Wien filter for cooled radioactive ion beams has been designed at Ion Guide Isotope Separator On Line technique (IGISOL). The purpose of such device is to eliminate doubly charged ions from the mass separated singly charged ions, based on q = +2-->q = +1 charge exchange process in an ion cooler, T

  6. Radioactive waste disposal fees-Methodology for calculation

    Science.gov (United States)

    Bemš, Július; Králík, Tomáš; Kubančák, Ján; Vašíček, Jiří; Starý, Oldřich

    2014-11-01

    This paper summarizes the methodological approach used for calculation of fee for low- and intermediate-level radioactive waste disposal and for spent fuel disposal. The methodology itself is based on simulation of cash flows related to the operation of system for waste disposal. The paper includes demonstration of methodology application on the conditions of the Czech Republic.

  7. Consequences of severe radioactive releases to Nordic Marine environment

    DEFF Research Database (Denmark)

    Iosjpe, M.; Isaksson, M.; Joensen, H.P.

    - or minor – radioactive releases to Nordic marine environment. As a reference, the release amounts from a 3000 MWth reactor size were used. Based on source term analyses, the chosen release fractions in the study were: iodine 20% (of the total core inventory), caesium 10%, tellurium 10%, strontium 0...

  8. Analysis of seawater circulation and radioactive concentration in the whole Arctic Ocean

    Science.gov (United States)

    Ochiai, Minoru; Wada, Akira; Takano, Tairyu

    The results of research on marine contamination in the regional areas (the Kara and Barents Seas) in the Arctic Ocean were reported at the Journal of the Japan Society for Marine Survey and Technology, Vol. 15(2). In the present research, the authors carried out flow analysis and concentration analysis of radioactive materials in the whole region of the Arctic Ocean, based on the release scenario. A numerical hybrid box model was developed. The results obtained agreed with the observed features in many respects. Especially, stream flows in Norwegian, Barents Sea and Kara Sea showed fairly realistic features. The flow field in the surface layer in the central Arctic Ocean agreed with that in previously known data. In nuclide dispersion model, nuclide decay, mixing, scavenging and interaction between seawater and bottom sediment layers were taken into consideration in order to improve accuracy of the dosage estimate. Based on nuclide (Pu-239 and Cs-137) release scenarios, the whole Arctic Ocean was subjected to analysis. A clear difference was recognized in the diffusion distribution according to the properties of nuclides, and concentration in the sediment is one or two orders higher than that in the seawater when the distribution factor of Kd value is large as in Pu-239.

  9. Study of the Production of Radioactive Isotopes through Cosmic Muon Spallation in KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    KamLAND Collaboration; Abe, S.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.; Yonezawa, E.; Yoshida, S.; Kozlov, A.; Murayama, H.; Busenitz, J.; Classen, T.; Grant, C.; Keefer, G.; Leonard, D. S.; McKee, D.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Gray, F.; Guardincerri, E.; Hsu, L.; Ichimura, K.; Kadel, R.; Lendvai, C.; Luk, K.-B.; O' Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D. A.; Jillings, C.; Mauger, C.; McKeown, R. D.; Vogel, P.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Piquemal, F.; Ricol, J.-S.; Decowski, M. P.

    2009-06-30

    Radioactive isotopes produced through cosmic muon spallation are a background for rare event detection in {nu} detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillator, and for checking estimates from current simulations based upon MUSIC, FLUKA, and Geant4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be (2.8 {+-} 0.3) x 10{sup -4} n/({mu} {center_dot} (g/cm{sup 2})). For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  10. Application of PbWO{sub 4} crystal scintillators in experiment to search for 2{beta} decay of {sup 116}Cd

    Energy Technology Data Exchange (ETDEWEB)

    Danevich, F.A. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine)]. E-mail: danevich@kinr.kiev.ua; Georgadze, A.Sh. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Kobychev, V.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Kropivyansky, B.N. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Nagorny, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Nikolaiko, A.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Poda, D.V. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Tretyak, V.I. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Vyshnevskyi, I.M. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Yurchenko, S.S. [Institute for Nuclear Research, Prospekt Nauki 47, MSP 03680 Kiev (Ukraine); Grinyov, B.V. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Nagornaya, L.L. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Pirogov, E.N. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Ryzhikov, V.D. [Institute for Scintillation Materials, 61001 Kharkov (Ukraine); Brudanin, V.B. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Vylov, Ts. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Fedorov, A. [Institute for Nuclear Problems, 220050 Minsk (Belarus); Korzhik, M. [Institute for Nuclear Problems, 220050 Minsk (Belarus); Lobko, A. [Institute for Nuclear Problems, 220050 Minsk (Belarus); Missevitch, O. [Institute for Nuclear Problems, 220050 Minsk (Belarus)

    2006-01-01

    Lead tungstate (PbWO{sub 4}) crystal scintillators are discussed as an active shield and light guides in {sup 116}Cd double-beta decay experiment with Cadmium tungstate (CdWO{sub 4}) scintillators. Scintillation properties and radioactive contamination of PbWO{sub 4} scintillators were investigated. Energy resolution of CdWO{sub 4} detector, coupled to PbWO{sub 4} light guide, was tested. Efficiency of PbWO{sub 4}-based active shield to suppress background from the internal contamination of PbWO{sub 4} crystals, as well as possible contribution from radioactivity of copper shield and phototubes were calculated. Using of lead tungstate crystal scintillators as high-efficiency 4{pi} active shield could allow to build sensitive 2{beta} experiment (T{sub 1/2}{sup 0{nu}}{sup 2{beta}}{approx}10{sup 26}yr) to search for 0{nu}2{beta} decay of {sup 116}Cd with {sup 116}CdWO{sub 4} crystal scintillators.

  11. Decay of Hoyle state

    Indian Academy of Sciences (India)

    S Bhattacharya; T K Rana; C Bhattacharya; S Kundu; K Banerjee; T K Ghosh; G Mukherjee; R Pandey; P Roy

    2014-11-01

    The prediction of Hoyle state was necessitated to explain the abundance of carbon, which is crucial for the existence of life on Earth and is the stepping stone for understanding the abundance of other heavier elements. After the experimental confirmation of its existence, soon it was realized that the Hoyle state was `different’ from other excited states of carbon, which led to intense theoretical and experimental activities over the past few decades to understand its structure. In recent times, precision, high statistics experiments on the decay of Hoyle state have been performed at the Variable Energy Cyclotron Centre, to determine the quantitative contributions of various direct 3 decay mechanisms of the Hoyle state. The present results have been critically compared with those obtained in other recent experiments and their implications have been discussed.

  12. Electroweak penguin B decays

    CERN Document Server

    Nikodem, Thomas

    2016-01-01

    Flavour Changing Neutral Currents (FCNC) are sensitive probes for physics beyond the Standard Model (SM), so-called New Physics. An example of a FCNC is the $b \\to s$ quark transition described by the electroweak penguin Feynman diagram shown in Figure 1. In the SM such FCNC are only allowed with a loop structure (as e:g: shown in the figure) and not by tree level processes. In the loops heavy particles appear virtually and do not need to be on shell. Therefore also not yet discovered heavy particles with up to a mass $\\mathcal{O}$(TeV) could virtually contribute significantly to observables. Several recent measurements of electroweak penguin B decays exhibit interesting tensions with SM predictions, most prominently in the angular observable $P'_5$ 5 of the decay $B^0 \\to K^{*0} \\mu^+ \\mu^1$[1], which triggered a lot of discussion in the theory community [2]-[14].

  13. Challenges in proton radioactivity studies - new emitters in the rare earth region.

    Science.gov (United States)

    Grzywacz, Robert

    2004-10-01

    Proton emitter studies offer a sensitive probe of the wave function composition for nuclei beyond the proton drip-line. In particular, the experiments on proton radioactivities in the rare earth region are allowing us to study the evolution of proton-emitting states as a function of changing deformation, from nearly spherical (e.g.^150Lu [1] or ^145Tm [2]) to strongly deformed (e.g. ^131Eu [3], ^135Tb [4] or ^141Ho [5]) shapes. The link between the measured observables (decay lifetimes and energies) and structure of the nuclei is provided by recently developed theories, which are able to model the proton tunneling process through the three dimensional potential barrier, see refs [6-8]. Very high detection efficiency and high sensitivity enable experiments at extremely low production cross sections, e.g. at the nanobarn level for the observation of ^135Tb in a (p6n) fusion-evaporation reaction channel [4]. Recent discoveries of proton radioactive nuclei will be reported. The experimental challenges will be illustrated with the example of the identification of new odd-odd emitter ^144Tm at the Recoil Mass Spectrometer [9] of Oak Ridge National Laboratory. The ^144Tm events were found in a weak ( 10 nb) p5n channel of the fusion reaction of ^58Ni beam at 340 MeV on a ^92Mo target. The observed decay energy of about 1.8 MeV and the half-life of the order of 1 μs suggest proton emission from the πh_11/2 orbital dominating the π-ν wave function. The detection of this very short proton emitter was made possible by use of a double-sided silicon strip detector connected to a fast data acquisition system [10] based on Digital Signal Processing. [1] P.G. Sellin et al., Phys. Rev. C47, 1933 (1993). [2] M. Karny et al., Phys. Rev. Lett. 90 , 012502 (2003). [3] A.A. Sonzogni et al., Phys. Rev. Lett. 83 , 1116 (1999). [4] P.J. Woods et al., Phys. Rev. C69 , 051302(R) (2004). [5] K. Rykaczewski, K. P. et al., in Proc. of Int. Conf. on Nuclear Structure ``Mapping the Triangle

  14. Teleportation via decay

    Indian Academy of Sciences (India)

    S Bose; P L Knight; M B Plenio; V Vedral

    2001-02-01

    We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity. We also show how this scheme can be modified to a teleportation with insurance.

  15. Charmless B decays

    Directory of Open Access Journals (Sweden)

    Martens Aurélien

    2014-04-01

    Full Text Available During 2011, LHCb has collected an integrated luminosity of 1.1 fb−1, giving rise to a large variety of measurements. Amongst these, measurements of CP violation in B decays play a central role. In particular CP violation measurements in charmless transitions of B mesons are of interest since they provide new or improved constraints on new physics contributions. These proceedings concentrate on LHCb results made publicin the first half of the year 2012.

  16. The true quantum face of the "exponential" decay law

    CERN Document Server

    Urbanowski, K

    2016-01-01

    Results of theoretical studies of the quantum unstable systems caused that there are rather widespread belief that a universal feature od the quantum decay process is the presence of three time regimes of the decay process: the early time (initial) leading to the Quantum Zeno (or Anti Zeno) Effects, "exponential" (or "canonical") described by the decay law of the exponential form, and late time characterized by the decay law having inverse--power law form. Based on the fundamental principles of the quantum theory we give the proof that there is no time interval in which the survival probability (decay law) could be a decreasing function of time of the purely exponential form but even at the "exponential" regime the decay curve is oscillatory modulated with a smaller or a large amplitude of oscillations depending on parameters of the model considered.

  17. Multifluid magnetohydrodynamic turbulent decay

    CERN Document Server

    Downes, Turlough P

    2011-01-01

    It is generally believed that turbulence has a significant impact on the dynamics and evolution of molecular clouds and the star formation which occurs within them. Non-ideal magnetohydrodynamic effects are known to influence the nature of this turbulence. We present the results of a suite of 512-cubed resolution simulations of the decay of initially super-Alfvenic and supersonic fully multifluid MHD turbulence. We find that ambipolar diffusion increases the rate of decay of the turbulence while the Hall effect has virtually no impact. The decay of the kinetic energy can be fitted as a power-law in time and the exponent is found to be -1.34 for fully multifluid MHD turbulence. The power spectra of density, velocity and magnetic field are all steepened significantly by the inclusion of non-ideal terms. The dominant reason for this steepening is ambipolar diffusion with the Hall effect again playing a minimal role except at short length scales where it creates extra structure in the magnetic field. Interestingl...

  18. Long-term stability of underground operated CZT detectors based on the analysis of intrinsic {sup 113}Cd β{sup −}-decay

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, J. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Gößling, C. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); Gehre, D., E-mail: daniel.gehre@tu-dresden.de [Technische Universität Dresden, Institut für Kern- und Teilchenphysik, Zellescher Weg 19, 01069 Dresden (Germany); Hagner, C.; Heidrich, N. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Klingenberg, R.; Kröninger, K.; Nitsch, C. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); Oldorf, C. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Quante, T.; Rajek, S. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); Rebber, H.; Rohatsch, K. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany); Tebrügge, J.; Temminghoff, R.; Theinert, R. [Technische Universität Dortmund, Lehrstuhl für Experimentelle Physik IV, Otto-Hahn-Str 4, 44221 Dortmund (Germany); and others

    2016-06-11

    The COBRA collaboration operates a demonstrator setup at the underground facility Laboratori Nazionali del Gran Sasso (LNGS, located in Italy) to prove the technological capabilities of this concept for the search for neutrinoless double beta-decay. The setup consists of 64 (1×1×1) cm{sup 3} Cadmium-Zinc-Telluride (CZT) detectors in Coplanar-Grid (CPG) configuration. One purpose of this demonstrator is to test if reliable long-term operation of CZT-CPG detectors in such a setup is possible. The demonstrator has been operated under ultra low-background conditions for more than three years and collected data corresponding to a total exposure of 218 kg days. The presented study focuses on the long-term stability of CZT detectors by analyzing the intrinsic, fourfold forbidden non-unique {sup 113}Cd single beta-decay. It can be shown that CZT detectors can be operated stably for long periods of time and that the {sup 113}Cd single beta-decay can be used as an internal monitor of the detector performance during the runtime of the experiment.

  19. Occupational exposure to natural radioactivity in the zirconium mineral manufacturing industries

    Energy Technology Data Exchange (ETDEWEB)

    Ballesteros, L.; Zarza, I.; Ortiz, J.; Serradell, V. [Valencia Univ. Politecnica, Lab. de Radiactividad Ambiental (Spain)

    2006-07-01

    detectors) is used. Dust samples from environment are analysed for measurement of {sup 210}Pb and {sup 210}Po as well. {sup 210}Pb is quantified by a beta measurement in a low background proportional counter, while a Si-surface-barrier alpha detector is used for Po- 210 spectrometry. Finally, an estimation of the radiation dose received by workers is performed, based on the previous measurements. External exposure is caused prevalently by gamma radiation from radionuclides in the {sup 238}U and {sup 232}Th series. Internal exposure is linked to radionuclides intake, mainly thought inhalation of {sup 222}Rn, its short-lived decay products, {sup 210}Pb and {sup 210}Po. (authors)

  20. Radioactive implants for medical applications; Radioaktive Implantate fuer medizinische Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, M.

    2008-07-01

    dosimetry of 1-2 MeV electrons, the challenge arises from the short range (few millimeters only) in the tissue and the resulting steep dose decay. Therefore a Monte Carlo Simulation has been developed, based on the library GEANT4. In this dose planning system, apart form the possibility of schematic geometry, calculations based on patients computer tomography data have been made possible. For the validation of this simulation, a system for three-dimensional dosimetric measurements has been developed by means of a plastic scintillator in a water phantom. The simulations could be reproduced within a deviation of 10%. Furthermore, to establish a quality control for each implant produced, an electron counter system has been developed to measure activity. The calibration has been carried out by liquid scintillation counting. Additionally, Monte Carlo Simulations have been performed to allow for calibration of implant materials, which can hardly be diluted such as the used materials silicone or nickel titanium alloys. The measured changes of the material properties of silicone and the bioabsorbable polymer PLGA, which occur due to the production process, were reasonable, confirming the suitability as an implant material, in particular for the long-lasting fixation of the radionuclide. The implants have been tested in the context of two preclinical studies: (i) Otorhinolaryngology faces problems with congested paranasal sinuses, which entail infections. By the implantation of a radioactive silicone stent with an irradiation time of 7 days, it has been shown that an artificially created opening can be kept open on a long-term basis. (ii) In the field of ophthalmology the glaucoma is a wide-spread disease, which can cause blindness, resulting from an elevated intra-ocular pressure. However, it can be treated by a surgical intervention. For the first time, a bioabsorbable, radioactive implant has been used that is suitable to keep the artificially created drainage open, and hence, is