Production of chemically reactive radioactive ion beams through on-line separation

International Nuclear Information System (INIS)

Joinet, A.

2003-10-01

The ISOL (isotope separation on line) allows the production of secondary radioactive ion beams through spallation or fragmentation or fission reactions that take place in a thick target bombarded by a high intensity primary beam. The challenge is to increase the intensity and purity of the radioactive beam. The optimization of the system target/source requires the right choice of material for the target by taking into account the stability of the material, its reactivity and the ionization method used. The target is an essential part of the system because radioactive elements are generated in it and are released more or less quickly. Tests have been made in order to select the best fitted material for the release of S, Se, Te, Ge and Sn. Materials tested as target filling are: ZrO 2 , Nb, Ti, V,TiO 2 , CeO x , ThO 2 , C, ZrC 4 and VC). Other molecules such as: COSe, COS, SeS, COTe, GeS, SiS, SnS have been studied to ease the extraction of recoil nuclei (Se, S, Te, Ge and Sn) produced inside the target

Spes: An intense source of Neutron-Rich Radioactive Beams at Legnaro

Science.gov (United States)

Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Monetti, A.; Rossignoli, M.; Ballan, M.; Borgna, F.; D'Agostini, F.; Gramegna, F.; Prete, G.; Meneghetti, G.; Ferrari, M.; Zenoni, A.

2018-02-01

The Isotope Separation On-Line (ISOL) method for the production of Radioactive Ion Beams (RIB) is attracting significant interest in the worldwide nuclear physics community. Within this context the SPES (Selective Production of Exotic Species) RIB facility is now under construction at INFN LNL (Istituto Nazionale di Fisica Nucleare Laboratori Nazionali di Legnaro). This technique is established as one of the main techniques for high intensity and high quality beams production. The SPES facility will produce n-rich isotopes by means of a 40 MeV proton beam, emitted by a cyclotron, impinging on a uranium carbide multi-foil fission target. The aim of this work is to describe the most important results obtained by the study of the on-line behavior of the SPES production target assembly. This target system will produce RIBs at a rate of about 1013 fissions per second, it will be able to dissipate a total power of up to 10 kW, and it is planned to work continuously for 2 week-runs of irradiation. ISOL beams of 24 different elements will be produced, therefore a target and ion source development is ongoing to ensure a great variety of produced isotopes and to improve the beam intensity and purity.

Vietnam Project For Production Of Radioactive Beam Based On ISOL Technique With The Dalat Reactor

International Nuclear Information System (INIS)

Le Hong Khiem; Phan Viet Cuong; Fadi Ibrahim

2011-01-01

The presence in Vietnam of Dalat nuclear reactor dedicated to fundamental studies is a unique opportunity to produce Radioactive Ion (RI) Beams with the fission of a 235 U induced by the thermal neutrons produced by the reactor. We propose to produce RI beams at the Dalat nuclear reactor using ISOL (Isotope Separation On-Line) technique. This project should be a unique opportunity for Vietnamese nuclear physics community to use its own facilities to produce RI beams for studying nuclear physics at an international level. (author)

A rich revenue from the use of radioactive beams and radioactive targets: recent highlights from the nTOF and ISOLDE facilities (1/2)

CERN Multimedia

CERN. Geneva

2008-01-01

The On-Line Isotope Mass Separator ISOLDE is a facility dedicated to the production of a large variety of radioactive ion beams for a great number of different experiments, e.g. in the field of nuclear and atomic physics, solid-state physics, life sciences and material science. At ISOLDE, radioactive nuclides are produced in thick high-temperature targets via spallation, fission or fragmentation reactions. The targets are placed in the external proton beam of the PSB, which has an energy of 1.0 or 1.4 GeV and an intensity of about 2 microA. The target and ion-source together represent a small chemical factory for converting the nuclear reaction products into a radioactive ion beam. An electric field accelerates the ions, which are mass separated and steered to the experiments. Until now more than 600 isotopes of more than 60 elements (Z=2 to 88) have been produced with half-lives down to milliseconds and intensities up to 1011 ions per second. Through the advent of post-accelerated beams with the REX-ISOLDE c...

Cluster radioactivity and very asymmetric fission through quasi-molecular shapes

International Nuclear Information System (INIS)

Royer, G.

1997-01-01

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 14 C radioactivity is not correctly described within the fission hypothesis. The 14 C and apparently also the 20 O are probably pre-born in the parent nucleus, the emission being similar to the α decay process. (author)

Preliminary results utilizing high-energy fission product γ-rays to detect fissionable material in cargo

Science.gov (United States)

Slaughter, D. R.; Accatino, M. R.; Bernstein, A.; Church, J. A.; Descalle, M. A.; Gosnell, T. B.; Hall, J. M.; Loshak, A.; Manatt, D. R.; Mauger, G. J.; Moore, T. L.; Norman, E. B.; Pohl, B. A.; Pruet, J. A.; Petersen, D. C.; Walling, R. S.; Weirup, D. L.; Prussin, S. G.; McDowell, M.

2005-12-01

A concept for detecting the presence of special nuclear material (235U or 239Pu) concealed in intermodal cargo containers is described. It is based on interrogation with a pulsed beam of 7 MeV neutrons that produce fission events and their β-delayed neutron emission or β-delayed high-energy γ radiation between beam pulses provide the detection signature. Fission product β-delayed γ-rays above 3 MeV are nearly 10 times more abundant than β-delayed neutrons and are distinct from natural radioactivity and from nearly all of the induced activity in a normal cargo. Detector backgrounds and potential interferences with the fission signature radiation have been identified and quantified.

A target concept for intense radioactive beams in the 132Sn Region

International Nuclear Information System (INIS)

Nolen, J.A. Jr.

1993-01-01

To produce intense secondary beams of radioactive isotopes, primary beams of up to 100 kW are being proposed at some facilities. There are plans to test production targets with 800 MeV protons at such higher power at the Rutherford Appleton Laboratory. In this paper the use of high energy neutrons as a possible alternative is presented. The concept is to generate an intense beam of neutrons in a well-cooled target with a primary deuteron beam. The neutrons have a high cross section for producing fission fragments in a thick uranium target which is coupled to the ion source for the secondary beams. The effective target thickness is large and the power dissipated in the ISOL target is relatively small, which should lead to intense beams of neutron-rich, intermediate-mass isotopes such as 132 Sn

Automatic control and monitoring of the MIT fission converter beam

International Nuclear Information System (INIS)

Wilson, B.A.; Riley, K.J.; Harling, O.K.

2000-01-01

An automated control and monitoring system for the new MIT high intensity epithermal neutron irradiation facility has been designed and constructed. The neutron beam is monitored with fission counters located at the periphery of the beam near the patient position. Control of the beam is accomplished with redundant Programmable Logic Controllers (PLCs). These industrial controllers open and close the three shutters of the Fission Converter Beam. The control system uses a series of robust components to assure that the prescribed fluence is delivered. This paper discusses the design and implementation of this system. (author)

Radioactive ion beam facilities at INFN LNS

International Nuclear Information System (INIS)

Rifuggiato, D; Calabretta, L; Celona, L; Chines, F; Cosentino, L; Cuttone, G; Finocchiaro, P; Pappalardo, A; Re, M; Rovelli, A

2011-01-01

Radioactive ion beams are produced at INFN- Laboratori Nazionali del Sud (LNS) by means of the two operating accelerators, the Tandem and the Superconducting Cyclotron (CS), originally designed to accelerate stable beams. Both the ISOL (Isotope Separation On Line) and the IFF (In-Flight Fragmentation) methods are exploited to produce RIBs in two different ways at different energies: in the first case, the Cyclotron is the primary accelerator and the Tandem accelerates the secondary beams, while in the second case radioactive fragments are produced by the Cyclotron beam in a thin target with energies comparable to the primary beam energy. The ISOL facility is named EXCYT (Exotics at the Cyclotron and Tandem) and was commissioned in 2006, when the first radioactive beam ( 8 Li) has been produced. The IFF installation is named FRIBs (in Flight Radioactive Ion Beams), and it has started to produce radioactive beams in 2001, placing a thin target in the extraction beam line of the Cyclotron. The development of both facilities to produce and accelerate radioactive ion beams at LNS, is briefly described, with some details on the future prospects that are presently under consideration or realization.

Production of high intensity radioactive beams

International Nuclear Information System (INIS)

Nitschke, J.M.

1990-04-01

The production of radioactive nuclear beams world-wide is reviewed. The projectile fragmentation and the ISOL approaches are discussed in detail, and the luminosity parameter is used throughout to compare different production methods. In the ISOL approach a thin and a thick target option are distinguished. The role of storage rings in radioactive beam research is evaluated. It is concluded that radioactive beams produced by the projectile fragmentation and the ISOL methods have complementary characteristics and can serve to answer different scientific questions. The decision which kind of facility to build has to depend on the significance and breadth of these questions. Finally a facility for producing a high intensity radioactive beams near the Coulomb barrier is proposed, with an expected luminosity of ∼10 39 cm -2 s -1 , which would yield radioactive beams in excess of 10 11 s -1 . 9 refs., 3 figs., 7 tabs

The REX-ISOLDE-project and the Munich Accelerator for Fission Fragments MAFF

CERN Document Server

Habs, D; Assmann, R W; Emhofer, S; Engels, O; Gross, M; Kester, O; Maier, H J; Reiter, P; Sieber, T; Thirolf, P G

2001-01-01

After a general discussion of ISOL-facilities in Europe we focus on the present status of the REX-ISOLDE facility at CERN and the Munich Accelerator for Fission Fragments MAFF. At REX-ISOLDE in 2001 radioactive beams of ISOLDE will be accelerated to (0.8-2.4) MeV/u. At the new Munich high-flux reactor FRM-II a production target of MAFF with 10$^{14}$ fissions/s is under design. Probably in 2003 intense low-energy beams ( approximately=10$^{11}$/s) of very neutron-rich fission fragments will be available. For MAFF a linac is being developed, which will accelerate the ions after charge breeding to energies between 3.7 and 5.9 MeV/u. In the long term a recycling ring with large momentum acceptance will further increase the radioactive beam intensities by a factor of 10$^{2}$-10$^{3}$ for specific experiments. (33 refs).

Radioactive ion beam development for the SPIRAL 2 project

International Nuclear Information System (INIS)

Pichard, A.

2010-01-01

This thesis focuses on the study of radioactive ion beam production by the ISOL method for the SPIRAL 2 project. The production of light ion beams is studied and the potential in-target yields of two beams are appraised. The neutron-rich 15 C yield in an oxide target is estimated with simulations (MCNPx, EAF-07) and experimental data bases; the neutron-deficient 14 O yield is estimated thanks to a new measurement of the 12 C( 3 He, n) 14 O reaction excitation function. Based on thermal simulations, a first design of the production target is presented. This thermal study gives the necessary answers for the detailed design of the system able to reach a production yield 140 times higher than with SPIRAL 1. The production of radioactive ion beams coming from fissions in the UCx target is also studied and more particularly effusion and ionisation processes. A global study and an off-line tests campaign allow essential knowledge to the design of the surface ionisation source for SPIRAL 2 to be acquired. A first prototype of this ion source dedicated to alkali and alkaline-earth element production has been built and a thermal calibration performed. Ionisation efficiency and time response of the target-ion source system have been measured at different target temperatures and for different noble gases. These measurements allow evaluation of the impact of effusion and ionisation processes on the production efficiency of different alkali and noble gases isotopes as a function of their half-life. (author) [fr

ISOLDE experiment explores new territory in nuclear fission

CERN Multimedia

CERN Bulletin

2011-01-01

An international collaboration led by the University of Leuven, Belgium, exploiting ISOLDE’s radioactive beams, has recently discovered an unexpected new type of asymmetric nuclear fission, which challenges current theories. The surprising result opens the way for new nuclear structure models and further theories to elucidate the question.   Resonance Ionization Laser Ion Source (RILIS) in action at ISOLDE. RILIS was instrumental in providing the pure beam necessary for the successful nuclear fission experiment. In nuclear fission, the nucleus splits into two fragments (daughter nuclei), releasing a huge amount of energy. Nuclear fission is exploited in power plants to produce energy. From the fundamental research point of view, fission is not yet fully understood decades after its discovery and its properties can still surprise nuclear physicists. The way the process occurs can tell us a lot about the internal structure of the nucleus and the interactions taking place inside the com...

EURISOL-DS Multi-MWatt Hg Target: Neutron flux and fission rate calculations for the MAFF configuration

CERN Document Server

Romanets, Y; Vaz, P; Herrera-Martinez, A; Kadi, Y; Kharoua, C; Lettry, J; Lindroos, M

The EURISOL (The EURopean Isotope Separation On-Line Radioactive Ion Beam) project aims at producing high intensity radioactive ion beams produced by neutron induced fission on a fissile target (235U) surrounding a liquid mercury converter. A proton beam of 1 GeV and 4 MW impinges on the Hg converter generating by spallation reactions high neutron fluxes. In this work the state-of-the-art Monte Carlo codes MCNPX and FLUKA were used to assess the neutronics performance of the system which geometry, inspired from the MAFF concept, allows a versatile manipulation of the fission targets. The objective of the study was to optimize the geometry of the system and the materials used in the fuel and reflector elements of the system, in order to achieve the highest possible fission rate.

Induced fission track distribution from highly radioactive particles in fallout materials

International Nuclear Information System (INIS)

Hashimoto, Tetsuo; Okada, Tatemichi

1987-01-01

Some highly radioactive fallout particles (GPs) from the 19th Chinese nuclear detonation were followed to the neutron irradiation in a reactor after sandwiched with mica detectors. The interesting star-like fission track patterns were revealed on the etched surface of the mica detectors. The simple chemical separation procedure for the GPs was applied for the separation of U and Pu as fissile elements and the both resultant fractions were examined with the similar high sensitive fission tracking detection. Subsequently, a representative track pattern from a black spherical particle was subjected to the determination of fissile nuclide content; comparing the total fission events evaluated on the basis of the numerical calculation of track densities with the total thermal neutron fluence. The results implied that the uranium is responsible for the main fissile nuclide remaining within a particle as unfissioned fractions and should be certainly enriched with respect to U-235 within such small fallout particles. This sophisticated method was also applied to determine the dead GPs, which have been highly radioactive particles just after the detonations, in the rain and snow-residual materials. Many induced star-like fission tracks verified certainly that there remains a lot of dead particles in the atmosheric environment till nowadays. (author)

Radioactive heavy ion secondary beams

International Nuclear Information System (INIS)

Bimbot, R.

1987-01-01

The production of secondary radioactive beams at GANIL using the LISE spectrometer is reviewed. The experimental devices, and secondary beam characteristics are summarized. Production of neutron rich secondary beams was studied for the systems Ar40 + Be at 44 MeV/u, and 018 + Be at 45 and 65 MeV/u. Partial results were also obtained for the system Ne22 + Ta at 45 MeV/u. Experiments using secondary beams are classified into two categories: those which correspond to fast transfer of nuclei from the production target to a well shielded observation point; and those in which the radioactive beam interacts with a secondary target

Dual-fission chamber and neutron beam characterization for fission product yield measurements using monoenergetic neutrons

Science.gov (United States)

Bhatia, C.; Fallin, B.; Gooden, M. E.; Howell, C. R.; Kelley, J. H.; Tornow, W.; Arnold, C. W.; Bond, E. M.; Bredeweg, T. A.; Fowler, M. M.; Moody, W. A.; Rundberg, R. S.; Rusev, G.; Vieira, D. J.; Wilhelmy, J. B.; Becker, J. A.; Macri, R.; Ryan, C.; Sheets, S. A.; Stoyer, M. A.; Tonchev, A. P.

2014-09-01

A program has been initiated to measure the energy dependence of selected high-yield fission products used in the analysis of nuclear test data. We present out initial work of neutron activation using a dual-fission chamber with quasi-monoenergetic neutrons and gamma-counting method. Quasi-monoenergetic neutrons of energies from 0.5 to 15 MeV using the TUNL 10 MV FM tandem to provide high-precision and self-consistent measurements of fission product yields (FPY). The final FPY results will be coupled with theoretical analysis to provide a more fundamental understanding of the fission process. To accomplish this goal, we have developed and tested a set of dual-fission ionization chambers to provide an accurate determination of the number of fissions occurring in a thick target located in the middle plane of the chamber assembly. Details of the fission chamber and its performance are presented along with neutron beam production and characterization. Also presented are studies on the background issues associated with room-return and off-energy neutron production. We show that the off-energy neutron contribution can be significant, but correctable, while room-return neutron background levels contribute less than <1% to the fission signal.

Nuclear fission: a review of experimental advances and phenomenology

Science.gov (United States)

Andreyev, A. N.; Nishio, K.; Schmidt, K.-H.

2018-01-01

In the last two decades, through technological, experimental and theoretical advances, the situation in experimental fission studies has changed dramatically. With the use of advanced production and detection techniques both much more detailed and precise information can now be obtained for the traditional regions of fission research and, crucially, new regions of nuclei have become routinely accessible for fission studies. This work first of all reviews the recent developments in experimental fission techniques, in particular the resurgence of transfer-induced fission reactions with light and heavy ions, the emerging use of inverse-kinematic approaches, both at Coulomb and relativistic energies, and of fission studies with radioactive beams. The emphasis on the fission-fragment mass and charge distributions will be made in this work, though some of the other fission observables, such as prompt neutron and γ-ray emission will also be reviewed. A particular attention will be given to the low-energy fission in the so far scarcely explored nuclei in the very neutron-deficient lead region. They recently became the focus for several complementary experimental studies, such as β-delayed fission with radioactive beams at ISOLDE(CERN), Coulex-induced fission of relativistic secondary beams at FRS(GSI), and several prompt fusion–fission studies. The synergy of these approaches allows a unique insight in the new region of asymmetric fission around {\\hspace{0pt}}180 Hg, recently discovered at ISOLDE. Recent extensive theoretical efforts in this region will also be outlined. The unprecedented high-quality data for fission fragments, completely identified in Z and A, by means of reactions in inverse kinematics at FRS(GSI) and VAMOS(GANIL) will be also reviewed. These experiments explored an extended range of mercury-to-californium elements, spanning from the neutron-deficient to neutron-rich nuclides, and covering both asymmetric, symmetric and transitional fission regions

Multi-channel probes to understand fission dynamics

Energy Technology Data Exchange (ETDEWEB)

Mosby, Shea Morgan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-04-15

Explaining the origin of the elements is a major outstanding question in nuclear astrophysics. Observed elemental abundance distribution shows strong nuclear physics effects. In conclusion, neutron-induced reactions are important for nuclear astrophysics and applied fields in nuclear energy and security. LANSCE has a program to address many of these questions directly with neutron beams on (near-)stable nuclei. Increasing demand for correlated data to test details of fission models poses additional challenges. Possibilities exist to extend existing experimental efforts to radioactive beam facilities. Kinematic focusing from using inverse kinematics has potential to circumvent some challenges associated with measuring correlations between fission output channels.

Freedom: a transient fission-product release model for radioactive and stable species

International Nuclear Information System (INIS)

Macdonald, L.D.; Lewis, B.J.; Iglesias, F.C.

1989-05-01

A microstructure-dependent fission-gas release and swelling model (FREEDOM) has been developed for UO 2 fuel. The model describes the transient release behaviour for both the radioactive and stable fission-product species. The model can be applied over the full range of operating conditions, as well as for accident conditions that result in high fuel temperatures. The model accounts for lattice diffusion and grain-boundary sweeping of fusion products to the grain boundaries, where the fission gases accumulate in grain-face bubbles as a result of vacancy diffusion. Release of fission-gas to the free void of the fuel element occurs through the interlinkage of bubbles and cracks on the grain boundaries. This treatment also accounts for radioactive chain decay and neutron-induced transmutation effects. These phenomena are described by mass balance equations which are numerically solved using a moving-boundary, finite-element method with mesh refinement. The effects of grain-face bubbles on fuel swelling and fuel thermal conductivity are included in the ELESIM fuel performance code. FREEDOM has an accuracy of better than 1% when assessed against an analytic solution for diffusional release. The code is being evaluated against a fuel performance database for stable gas release, and against sweep-gas and in-cell fission-product release experiments at Chalk River for active species

Radioactive beam production at the Bevalac

International Nuclear Information System (INIS)

Alonso, J.R.; Feinberg, B.; Kalnins, J.G.; Krebs, G.F.; McMahan, M.A.; Tanihata, I.

1989-10-01

At the Bevalac radioactive beams are routinely produced by the fragmentation process. The effectiveness of this process with respect to the secondary beam's emittance, intensity and energy spread depends critically on the nuclear reaction kinematics and the magnitude of the incident beam energy. When this beam energy significantly exceeds the energies of the nuclear reaction process, many of the qualities of the incident beam can be passed on to the secondary beam. Factors affecting secondary beam quality are discussed along with techniques for isolating and purifying a specific reaction product. The on-going radioactive beam program at the Bevalac is used as an example with applications, present performance and plans for the future. 6 refs., 6 figs., 1 tab

Polarized secondary radioactive beams

International Nuclear Information System (INIS)

Zaika, N.I.

1992-01-01

Three methods of polarized radioactive nuclei beam production: a) a method nuclear interaction of the non-polarized or polarized charged projectiles with target nuclei; b) a method of polarization of stopped reaction radioactive products in a special polarized ion source with than following acceleration; c) a polarization of radioactive nuclei circulating in a storage ring are considered. Possible life times of the radioactive ions for these methods are determined. General schemes of the polarization method realizations and depolarization problems are discussed

Detection systems for radioactive ion beams

International Nuclear Information System (INIS)

Savajols, H.

2002-01-01

Two main methods are used to produce radioactive ion beams: -) the ISOL method (isotope separation on-line) in which the stable beam interacts with a thick target, the reaction products diffuse outside the target and are transferred to a source where they are ionized, a mass separator and a post-accelerator drive the selected radioactive ions to the right energy; -) the in-flight fragmentation method in which the stable beam interacts with a thin target, the reaction products are emitted from the target with a restricted angular distribution and a velocity close to that of the incident beam, the experimenter has to take advantage from the reaction kinetics to get the right particle beam. Characteristic time is far longer with the ISOL method but the beam intensity is much better because of the use of a post-accelerator. In both cases, the beam intensity is lower by several orders of magnitude than in the case of a stable beam. This article presents all the constraints imposed by radioactive beams to the detection systems of the reaction products and gives new technical solutions according to the type of nuclear reaction studied. (A.C.)

Development of the Holifield Radioactive Ion Beam Facility

International Nuclear Information System (INIS)

Tatum, B.A.

1997-01-01

The Holifield Radioactive Ion Beam Facility (HRIBF) construction project has been completed and the first radioactive ion beam has been successfully accelerated. The project, which began in 1992, has involved numerous facility modifications. The Oak Ridge Isochronous Cyclotron has been converted from an energy booster for heavy ion beams to a light ion accelerator with internal ion source. A target-ion source and mass analysis system have been commissioned as key components of the facility's radioactive ion beam injector to the 25MV tandem electrostatic accelerator. Beam transport lines have been completed, and new diagnostics for very low intensity beams have been developed. Work continues on a unified control system. Development of research quality radioactive beams for the nuclear structure and nuclear astrophysics communities continues. This paper details facility development to date

Map of calculated radioactivity of fission product, 3

International Nuclear Information System (INIS)

Takeda, Tsuneo

1977-02-01

In this work, the radioactivities of fission products were calculated and summarized in contour maps and tables depending on irradiation and cooling times. The irradiation condition and other parameters used for the present calculation are shown in the followings. Neutron flux (N sub(th)): 3x10 13 n/sec/cm 2 Atom number of uranium: 1 mole (6x10 23 , ca. 271 gUO 2 ) Enrichment of U-235: 2.7% Range of irradiation time: 60-6x10 7 sec (ca. 1.9 y) Range of cooling time: 60-6x10 7 sec (ca. 1.9 y). Values of the neutron flux and the enrichment treated here are representative for common LWRs. The maps and tables of 560 nuclides are divided and compiled into the following three volumes. Vol. I: Maps of radioactivity of overall total, element total and each nuclide (Ni - Zr), Vol. II: Maps of radioactivity of each nuclide (Nb - Sb), Vol. III: Maps of radioactivity of each nuclide (Te - Tm). (auth.)

Map of calculated radioactivity of fission product, (1)

International Nuclear Information System (INIS)

Takeda, Tsuneo

1977-02-01

In this work, the radioactivities of fission products were calculated and summarized in contour maps and tables depending on irradiation and cooling times. The irradiation condition and other parameters used for the present calculation are shown in the followings. Neutron flux (N sub(th)): 3x10 13 n/sec/cm 2 Atom number of uranium: 1 mole (6x10 23 , ca. 271 gUO 2 ) Enrichment of U-235: 2.7% Range of irradiation time: 60-6x10 7 sec (ca. 1.9 y) Range of cooling time: 60-6x10 7 sec (ca. 1.9 y). Values of the neutron flux and the enrichment treated here are representative for common LWRs. The maps and tables of 560 nuclides are divided and compiled into the following three volumes. Vol. I Maps of radioactivity of overall total, element total and each nuclide (Ni - Zr) Vol. II Maps of radioactivity of each nuclide (Nb - Sb) Vol. III Maps of radioactivity of each nuclide (Te - Tm) (auth.)

Map of calculated radioactivity of fission product, 2

International Nuclear Information System (INIS)

Takeda, Tsuneo

1977-02-01

In this work, the radioactivities of fission products were calculated and summarized in contour maps and tables depending on irradiation and cooling times. The irradiation condition and other parameters used for the present calculation are shown in the followings. Neutron flux (N sub(th)): 3x10 13 n/sec/cm 2 Atom number of uranium: 1 mole (6x10 23 , ca. 271 gUO 2 ) Enrichment of U-235: 2.7% Range of irradiation time: 60-6x10 7 sec (ca. 1.9 y) Range of cooling time: 60-6x10 7 sec (ca. 1.9 y). Values of the neutron flux and the enrichment treated here are representative for common LWRs. The maps and tables of 560 nuclides are divided and compiled into the following three volumes. Vol. I: Maps of radioactivity of overall total, element total and each nuclide (Ni - Zr), Vol. II: Maps of radioactivity of each nuclide (Nb - Sb), Vol. III: Maps of radioactivity of each nuclide (Te - Tm). (auth.)

Process for ultimate storage of radioactive fission products

International Nuclear Information System (INIS)

Baukal, W.; Gruenthaler, K.H.; Neumann, K.

1980-01-01

In order to exclude cracking in the cooling phase during sealing of radioactive oxidic fission products in glass melts, metallic filling elements - e.g. wires, tissues - are proposed to be incorporated in the mould before the glass melt is poured in. Especially nickel alloys with corrosion proof surface layers, e.g. titanium nitride, silicon carbide, silicon nitride, aluminium oxide, suit best. These elements reduce thermal stresses and effect high thermal conductance towards the mould wall. (UWI) [de

Cyclotrons for the production of radioactive beams

International Nuclear Information System (INIS)

Clark, D.J.

1990-01-01

This paper describes the characteristics and design choices for modern cyclotrons. Cyclotrons can be used in 3 areas in the radioactive beam field: the production of high energy heavy ion beams for use in fragmentation, the spallation of targets with high energy protons, and the acceleration of radioactive beams from low energy to the MeV/u range. 16 refs., 6 figs

National Centre for Radioactive Ion Beams (NCRIB)

International Nuclear Information System (INIS)

Chintalapudi, S.N.

1999-01-01

A dedicated National Centre for RIB (NCRIB) proposed discussed at several forums is presented. The production of (RIB) radioactive ion beams and applications of beams leading to competitive studies in nuclear structure, nuclear reactions, condensed matter, bio-science and radioactive isotope production etc. are mentioned

Radioactive beams in Europe

International Nuclear Information System (INIS)

Warner, D.D.

1993-01-01

In its report open-quotes Nuclear Physics in Europe - Opportunities and Perspectivesclose quotes, NuPECC concluded that physics with radioactive beams represents one of the foremost frontiers in nuclear physics. It therefore set up a study group to produce a report on the physics case for radioactive beams, together with a comparison of the relative merits of the various European facilities, operational or planned, and the R ampersand D required to achieve the desired goals. This paper presents some of the results of that report and concentrates on the latter two aspects of the task assigned to the Study Group. The facilities discussed are those planning to use the two-accelerator method to produce beams in the energy range of 0.5-25Mev/A. In addition, a report is given on the status of the recently-approved Test Bed facility at the Rutherford Appleton Laboratory, where the aim is to test the ability of existing ISOL target/ion-source technology to withstand a primary proton beam intensity of 100μA

Experimental studies with radioactive ion beams

International Nuclear Information System (INIS)

Sastry, D.L.; Sree Krishna Murty, G.; Chandrasekhar Rao, M.V.S.

1991-01-01

The sources of information presented are essentially taken from the papers reported at several international seminars and those appeared in the Journal of Nuclear Instruments and Methods in Physics Research. Production and usage of radioactive ion beams (RIB) in research have received the attention of scientists all over the world during the past six years. The first radioactive ion beams ( 19 Ne) were produced at Bevalac for the purpose of medical research using a primary beam of energy 800 MeV/a.m.u. (author). 19 refs., 2 figs., 3 tabs

SPES: exotic beams for nuclear physics studies

International Nuclear Information System (INIS)

Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Vasquez, J.; Rossignoli, M.; Monetti, A.; Calderolla, M.; Prete, G.

2014-01-01

The SPES project at Laboratori di Legnaro of INFN (Italy) is concentrating on the production of neutron-rich radioactive nuclei for nuclear physics experiments using uranium fission at a rate of 10 13 fission/s. The emphasis on neutron-rich isotopes is justified by the fact that this vast territory has been little explored. The Radioactive Ion Beam (RIB) will be produced by the ISOL technique using proton induced fission on a direct target of UCx. The most critical element of the SPES project is the Multi-Foil Direct Target. Up to the present time, the proposed target represents an innovation in terms of its capability to sustain the primary beam power. This talk will present the status of the project financed by INFN, which is actually in the construction phase at Legnaro. In particular, developments related to the target and the ion-source activities using the surface ion source, plasma ion source, and laser ion source techniques will be reported. (author)

The ISOLDE Facility: Radioactive beams at CERN

CERN Multimedia

CERN. Geneva

2007-01-01

The Isope Separation On-Line (ISOL) technique evolved from chemical techniques used to separate radioactive isotopes off-line from irradiated "targets". The ISOL targets of today, used at e.g. ISOLDE, can be of many different types and in different phases but the isotopes are always delivered at very low energies making the technique ideal for study of ground state properties and collections for other applications such as solid state physics and medical physics. The possibility of accelerating these low energy beams for nuclear structure studies, and in the long term future for neutrino physics, is now being explored at first generation radioactive beam facilities. The upgrade towards HIE-ISOLDE aim to consolidate ISOLDE's position as a world leading radioactive nuclear beam facility and it will be a pre-cursor to a future all European ISOL facility, EURISOL, with order of magnitudes higher radioactive beam intensities and energies. Prerequisite knowledge and references: None

First inverse-kinematics fission measurements in a gaseous active target

Energy Technology Data Exchange (ETDEWEB)

Rodríguez-Tajes, C., E-mail: rodriguez@ganil.fr [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Bd. Henri Becquerel, 14076 Caen (France); Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Farget, F. [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Bd. Henri Becquerel, 14076 Caen (France); Acosta, L. [Departamento de Ciencias Integradas, Universidad de Huelva, E-21071 Huelva (Spain); Alvarez-Pol, H. [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Babo, M.; Boulay, F. [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Bd. Henri Becquerel, 14076 Caen (France); Caamaño, M. [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Damoy, S. [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Bd. Henri Becquerel, 14076 Caen (France); Fernández-Domínguez, B. [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Galaviz, D. [Centro de Física Nuclear da Universidade de Lisboa, CFNUL, 1649-003 Lisboa (Portugal); Grinyer, G.F.; Grinyer, J. [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Bd. Henri Becquerel, 14076 Caen (France); Harakeh, M.N. [KVI-CART, University of Groningen, Zernikelaan 25, NL-9747 AA Groningen (Netherlands); Konczykowski, P. [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); and others

2017-02-15

The fission of a variety of actinides was induced by fusion and transfer reactions between a {sup 238}U beam and {sup 12}C nuclei, in the active target MAYA. The performance of MAYA was studied, as well as its capability to reconstruct the fission-fragment trajectories. Furthermore, a full characterization of the different transfer reactions was achieved, and the populated excitation-energy distributions were investigated as a function of the kinetic energy in the entrance channel. The ratio between transfer- and fusion-induced fission cross-sections was also determined, in order to investigate the competition between both reaction types and its evolution with the incident energy. The experimental results will be discussed with a view to forthcoming radioactive-ion beam facilities, and next-generation active-target setups.

Inventories of radioactive fission products in the core of thermal nuclear reactor

International Nuclear Information System (INIS)

Marinkovic, N.

1977-01-01

As a part of the analysis concerning radiological consequences of a major LWR accident, inventories of the most significant radioactive nuclides and stable fission gases in the core of a PWR type reactor have been calculated. Calculations were performed by the DELFIN code using nuclide data and neutron flux data earlier obtained by the METHUSELAH code. Comparison with simplified calculation method show that it is quite rough for certain nuclides but the accuracy may be sufficient for safety analysis purposes recalling the inaccuracies in the later parts of fission product transport process (author)

Nucleon transfer reactions with radioactive beams

Science.gov (United States)

Wimmer, K.

2018-03-01

Transfer reactions are a valuable tool to study the single-particle structure of nuclei. At radioactive beam facilities transfer reactions have to be performed in inverse kinematics. This creates a number of experimental challenges, but it also has some advantages over normal kinematics measurements. An overview of the experimental and theoretical methods for transfer reactions, especially with radioactive beams, is presented. Recent experimental results and highlights on shell evolution in exotic nuclei are discussed.

BEARS: Radioactive ion beams at LBNL

International Nuclear Information System (INIS)

Powell, J.; Guo, F.Q.; Haustein, P.E.

1998-01-01

BEARS (Berkeley Experiments with Accelerated Radioactive Species) is an initiative to develop a radioactive ion-beam capability at Lawrence Berkeley National Laboratory. The aim is to produce isotopes at an existing medical cyclotron and to accelerate them at the 88 inch Cyclotron. To overcome the 300-meter physical separation of these two accelerators, a carrier-gas transport system will be used. At the terminus of the capillary, the carrier gas will be separated and the isotopes will be injected into the 88 inch Cyclotron's Electron Cyclotron Resonance (ECR) ion source. The first radioactive beams to be developed will include 20-min 11 C and 70-sec 14 O, produced by (p,n) and (p,α) reactions on low-Z targets. A test program is currently being conducted at the 88 inch Cyclotron to develop the parts of the BEARS system. Preliminary results of these tests lead to projections of initial 11 C beams of up to 2.5 x 10 7 ions/sec and 14 O beams of 3 x 10 5 ions/sec

Release of radioactive fission products from BN-600 reactor untight fuel elements

International Nuclear Information System (INIS)

Osipov, S.L.; Tsikunov, A.G.; Lisitsin, E.C.

1996-01-01

The experimental data on the release of radioactive fission products from BN-600 reactor untight fuel elements are given in the report. Various groups of radionuclides: inert gases Xe, Kr, volatile Cs, J, non-volatile Nb, and La are considered. The results of calculation-experimental study of transfer and distribution of radionuclides in the reactor primary circuit, gas system and sodium coolant are considered. It is shown that some complex radioactivity transfer processes can be described by simple mathematical models. (author)

Physics with energetic radioactive ion beams

International Nuclear Information System (INIS)

Henning, W.F.

1996-01-01

Beams of short-lived, unstable nuclei have opened new dimensions in studies of nuclear structure and reactions. Such beams also provide key information on reactions that take place in our sun and other stars. Status and prospects of the physics with energetic radioactive beams are summarized

Radioactive nuclear beam facilities based on projectile fragmentation

International Nuclear Information System (INIS)

Sherrill, B.M.

1992-01-01

The production of radioactive beams using direct separation techniques is discussed. The reaction mechanisms which can be used to produce radioactive beams with these techniques can be broadly divided into three groups, projectile fragmentation, nucleon transfer, and Coulomb disassociation. Radioactive nuclei produced in these ways have large forward momenta with relatively sharp angular distributions peaked near zero degrees which are suitable for collection with magnetic devices. Secondary beam intensities of up to a few percent of the primary beam intensity are possible, although depending on the production mechanism the beam emittance may be poor. Further beam purification can be achieved using atomic processes with profiled energy degraders. The features of the production reaction mechanism, separation techniques, and a review of world wide efforts are presented. The advantages and disadvantages of the method are presented, with discussion of techniques to overcome some of the disadvantages. (Author)

CERN: Producing radioactive beams

International Nuclear Information System (INIS)

Anon.

1994-01-01

Accelerating radioactive beams has long been of interest at CERN's ISOLDE on-line isotope separator - the possibility was discussed at a CERN Workshop on intermediate energy physics as early as 1977. Meanwhile, as was highlighted in the 1991 report of the Nuclear Physics European Collaboration Committee, widespread scientific interest in these beams has developed and a range of projects are proposed, under construction or operational throughout the world

Summary -- Experiments with Radioactive Beams Working Group

Energy Technology Data Exchange (ETDEWEB)

Vieira, D.J. [Los Alamos National Lab., NM (United States); Wiescher, M. [Notre Dame Univ., IN (United States)

1992-12-31

During the course of the workshop, a wide range of futuristic radioactive-beam experiments were discussed. These extended from the study of electroweak interactions in nuclei to materials science, nuclear astrophysics, and a host of nuclear physics investigations. Emphasis was placed on illustrating how these prototypical experiments could be done, discussing what types of detection systems would be needed, exploring the new problems which would be confronting the radioactive beam experimenter, and better defining the beam requirements. Contained herein is a summary of these discussions.

Time-dependent radioactivity distribution in MAFF

International Nuclear Information System (INIS)

Nebel, F.; Zech, E.; Faestermann, T.; Kruecken, R.; Maier-Komor, P.; Assmann, W.; Szerypo, J.; Gross, M.; Kester, O.; Thirolf, P.G.; Groetzschel, R.

2006-01-01

The Munich Accelerator for Fission Fragments is planned to be installed at the FRM II in Garching. It will operate a uranium-carbide-loaded graphite matrix as a target for neutron-induced fission. The radioactive reaction fragments leave the ion source as both, atoms and ions. For radiation safety it is imperative to have a basic understanding of the fragment distribution within the beam line. Atoms leaving the graphite matrix will spread like a gas and stick to surfaces depending on their species. A probabilistic Monte-Carlo approach is used to predict the surface coating of internal surfaces of the beam line for all fission nuclides. To decrease calculation time, the problem is reduced to two dimensions with the surface areas being a measure for the probability, that they are hit by a particle. The program is completely time dependent to implement radioactive decay. Ions leaving the fission ion source are transported by electrostatic means towards the mass pre-separator, a low-resolution dipole magnet with a complex slit system in the focal plane. All unwanted ions are stopped at the slits, resulting in a high level of radioactive contamination. While it is advantageous for shielding purposes to have the majority of the contamination in one point, precautions must be taken to ensure that it stays that way. Material corrosion caused by sputtering will release previously implanted radionuclides. To reduce this effect, different methods are under investigation, one of which is changing the slit geometry. The considered designs will be described and experimental results will be shown

Nuclear astrophysics at the Holifield Radioactive Ion Beam Facility

International Nuclear Information System (INIS)

Smith, M.S.

1994-01-01

The potential for understanding spectacular stellar explosions such as novae, supernovae, and X-ray bursts will be greatly enhanced by the availability of the low-energy, high-intensity, accelerated beams of proton-rich radioactive nuclei currently being developed at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory. These beams will be utilized in absolute cross section measurements of crucial (p, γ) capture reactions in efforts to resolve the substantial qualitative uncertainties in current models of explosive stellar hydrogen burning outbursts. Details of the nuclear astrophysics research program with the unique HRIBF radioactive beams and a dedicated experimental endstation--centered on the Daresbury Recoil Separator--will be presented

A Monte Carlo code to optimize the production of Radioactive Ion Beams by the ISOL technique

CERN Document Server

Santana-Leitner, M

2005-01-01

Currently the nuclear chart includes around 3000 nuclides, distributed as ${\\beta}^+$, ${\\beta}^-$ and $\\alpha$-emitters, stable and spontaneously fissioning isotopes. A similar amount of unknown nuclei belongs to the so-called \\textit{terra incognita}, the uncertain region contained also within the proton, neutron and (fast) fission driplines and thereby stable against nucleon emission. The exploration of this zone is to be assisted by the use of radioactive ion beams (RIB) and could provide a new understanding of several nuclear properties. Moreover, besides pointing at crucial questions such as the validity of the shell model, the dilute matter and the halo structure, challenging experiments outside nuclear physics are also attended, e.g., explanations of the nucleosythesis processes that may justify why the matter in the universe has evolved to present proportions of elements, and which represents a major challenge to nuclear physics. These, together with other fascinating research lines in particle physi...

Overview of linac applications at future radioactive beam facilities

International Nuclear Information System (INIS)

Nolen, J.A.

1996-01-01

There is considerable interest worldwide in the research which could be done at a next generation, advanced radioactive beam facility. To generate high quality, intense beams of accelerated radionuclides via the open-quotes isotope separator on-lineclose quotes (ISOL) method requires two major accelerator components: a high power (100 kW) driver device to produce radionuclides in a production target/ion source complex, and a secondary beam accelerator to produce beams of radioactive ions up to energies on the order of 10 MeV per nucleon over a broad mass range. In reviewing the technological challenges of such a facility, several types of modem linear accelerators appear well suited. This paper reviews the properties of the linacs currently under construction and those proposed for future facilities for use either as the driver device or the radioactive beam post-accelerator. Other choices of accelerators, such as cyclotrons, for either the driver or secondary beam devices of a radioactive beam complex will also be compared. Issues to be addressed for the production accelerator include the choice of ion beam types to be used for cost-effective production of radionuclides. For the post-accelerator the choice of ion source technology is critical and dictates the charge-to-mass requirements at the injection stage

Charge breeding of intense radioactive beams

CERN Document Server

Kester, O

2001-01-01

The efficient transformation of radioactive beams by charge breeding devices will critically influence the lay-out of the post accelerator of presently built first generation radioactive ion beam (RIB) facilities as well as new second generation facilities. The size of the post-accelerator needed to bring the unstable nuclei to the energies required to study nuclear reactions depends on the charge state of the radioactive ions. The capability to raise that charge state from 1+ to n+, where n may correspond to a charge-to- mass ratio of 0.15 or higher, will therefore produce an enormous reduction in cost as well as the possibility to accelerate heavier masses. Thus the efficiency of the charge breeding scheme in comparison to the stripping scheme will be explored in the frame of the EU-network charge breeding. The two possible charge breeding schemes using either an Electron Beam Ion Source (EBIS) or an Electron Cyclotron Resonance Ion Source (ECRIS), the demands to the sources and the present status of existi...

ISOL science at the Holifield Radioactive Ion Beam Facility

Energy Technology Data Exchange (ETDEWEB)

Beene, James R [ORNL; Bardayan, Daniel W [ORNL; Galindo-Uribarri, Alfredo {nmn} [ORNL; Gross, Carl J [ORNL; Jones, K. L. [University of Tennessee, Knoxville (UTK); Liang, J Felix [ORNL; Nazarewicz, Witold [ORNL; Stracener, Daniel W [ORNL; Tatum, B Alan [ORNL; Varner Jr, Robert L [ORNL

2011-01-01

The Holi eld Radioactive Ion Beam Facility, located in Oak Ridge, Tennessee, is operated as a National User Facility for the U.S. Department of Energy, producing high quality ISOL beams of short-lived, radioactive nuclei for studies of exotic nuclei, astrophysics research, and various societal applications. The primary driver, the Oak Ridge Isochronous Cyclotron, produces rare isotopes by bombarding highly refractory targets with light ions. The radioactive isotopes are ionized, formed into a beam, mass selected, injected into the 25-MV Tandem, accelerated, and used in experiments. This article reviews HRIBF and its science.

Nuclear incineration method for long life radioactive wastes

International Nuclear Information System (INIS)

Matsumoto, Takaaki; Uematsu, Kunihiko.

1987-01-01

Nuclear incineration method is the method of converting the long life radioactive nuclides in wastes to short life or stable nuclides by utilizing the nuclear reaction caused by radiation, unlike usual chemical incineration. By the nuclear incineration, the radioactivity of wastes increases in a short period, but the problems at the time of the disposal are reduced because of the decrease of long life radioactive nuclides. As the radiation used for the nuclear incineration, the neutron beam from fission and fusion reactors and accelerators, the proton beam and gamma ray from accelerators have been studied. The object of the nuclear incineration is actinide, Sr-90, Cs-137, I-129 and Tc-99. In particular, waste actinide emits alpha ray, and is strongly toxic, accordingly, the motive of attempting the nuclear incineration is strong. In Japan, about 24t of waste actinide will accumulate by 2000. The principle of the nuclear incineration, and the nuclear incineration using nuclear fission and fusion reactors and accelerators are described. The nuclear incineration using fission reactors was examined for the first time in 1972 in USA. It is most promising because it is feasible by the present technology without particular research and development. (Kako, I.)

A neutron beam facility for radioactive ion beams and other applications

Science.gov (United States)

Tecchio, L. B.

1999-06-01

In the framework of the Italian participation in the project of a high intensity proton facility for the energy amplifier and nuclear waste transmutations, LNL is involved in the design and construction of same prototypes of the injection system of the 1 GeV linac that consists of a RFQ (5 MeV, 30 mA) followed by a 100 MeV linac. This program has already been supported financially and the work is in progress. In this context LNL has proposed a project for the construction of a second generation facility for the production of radioactive ion beams (RIBs) by means of the ISOL method. The final goal is the production of neutron rich RIBs with masses ranging from 30 to 150 by using primary beams of protons, deuterons and light ions with energy of 100 MeV and 100 kW power. This project is expected to be developed in about 10 years from new and intermediate milestones and experiments are foreseen and under consideration for the next INFN five year plan (1999-2003). During that period the construction of a proton/deuteron accelerator of 10 MeV energy and 10 mA current, consisting of a RFQ (5 MeV, 30 mA) and a linac (10 MeV, 10 mA), and of a neutron area dedicated to the RIBs production and to the neutron physics, is proposed. Some remarks on the production methods will be presented. The possibility of producing radioisotopes by means of the fission induced by neutrons will be investigated and the methods of production of neutrons will be discussed. Besides the RIBs production, neutron beams for the BNCT applications and neutron physics are also planned.

Improvements of present radioactive beam facilities and new projects

International Nuclear Information System (INIS)

Mueller, A.C.

1995-01-01

A short overview is given over scheduled improvements of present radioactive beam facilities and of new projects. In order to put these into a coherent context the paper starts with a general section about the making of radioactive beams. (author)

Nuclear astrophysics with radioactive beams: a TRIUMF perspective

International Nuclear Information System (INIS)

Shotter, A.C.

2003-01-01

Explosive nuclear burning in stellar environments involves reactions with a wide range of isotopes. For isotopes that are unstable, information on relevant reaction rates can only generally be obtained at radioactive beam facilities. The ISAC facility at TRIUMF is purpose built to provide a wide range of radioactive beams for nuclear astrophysics purposes as well as a range of other science

Status of SPIRAL. The radioactive beam project at GANIL

International Nuclear Information System (INIS)

Lieuvin, M.

1995-01-01

SPIRAL, a radioactive ion beam facility (RIB) is under construction at GANIL (Caen, France). The heavy ion beams of GANIL will be used to produce radioactive atoms by the ISOL method. After ionisation by an ECR ion source (ECRIS), the low energy radioactive beam is axially injected on the first orbit of a k=265 compact cyclotron. The final energy will range between 1.7 and 25 MeV/u (harmonics 5 to 2) and the accelerated ions will be sent to the existing GANIL experimental areas. The present status of the project is described. (author)

High purity radioactive beams at the bevalac

International Nuclear Information System (INIS)

Alonso, J.R.; Chatterjee, A.; Tobias, C.A.

1979-03-01

Peripheral nuclear fragmentation reactions of primary Bevalac heavy ion beams are used to produce secondary beams of radioactive nuclei. The large cross section and small deflection of the projectile fragments lead to high production and delivery efficiency for these beams. Dispersive beam transport allows good separation and purification of the desired secondary beams. 11 C and 19 Ne beams of high purity and good intensity (almost 0.2% of the primary beam current) are presently being used for biomedical experiments

Proceedings of national seminar on physics with radioactive ion beams

International Nuclear Information System (INIS)

Chintalapudi, S.N.; Shyam, R.

1991-01-01

This volume containing the proceedings of the national seminar on physics with radioactive ion beams gives a broad overview of the developments taking place in the area of nuclear physics and accelerator physics with special emphasis on the utilization of radioactive ion beams for various studies. Topics covered include studies on nuclear structure and nuclear astrophysics and the wide ranging applications of radioactive ion beams in these and other areas of nuclear sciences. Papers relevant to INIS are indexed separately

Production of chemically reactive radioactive ion beams through on-line separation; Production de faisceaux d'ions radioactifs chimiquement reactifs par separation en ligne

Energy Technology Data Exchange (ETDEWEB)

Joinet, A

2003-10-01

The ISOL (isotope separation on line) allows the production of secondary radioactive ion beams through spallation or fragmentation or fission reactions that take place in a thick target bombarded by a high intensity primary beam. The challenge is to increase the intensity and purity of the radioactive beam. The optimization of the system target/source requires the right choice of material for the target by taking into account the stability of the material, its reactivity and the ionization method used. The target is an essential part of the system because radioactive elements are generated in it and are released more or less quickly. Tests have been made in order to select the best fitted material for the release of S, Se, Te, Ge and Sn. Materials tested as target filling are: ZrO{sub 2}, Nb, Ti, V,TiO{sub 2}, CeO{sub x}, ThO{sub 2}, C, ZrC{sub 4} and VC). Other molecules such as: COSe, COS, SeS, COTe, GeS, SiS, SnS have been studied to ease the extraction of recoil nuclei (Se, S, Te, Ge and Sn) produced inside the target.

Radioactive ion beams and techniques for solid state research

International Nuclear Information System (INIS)

Correia, J.G.

1998-01-01

In this paper we review the most recent and new applications of solid state characterization techniques using radioactive ion beams. For such type ofresearch, high yields of chemically clean ion beams of radioactive isotopesare needed which are provided by the on-line coupling of high resolution isotope separators to particle accelerators, such as the isotope separator on-line (ISOLDE) facility at CERN. These new experiments are performed by an increasing number of solid state groups. They combine nuclear spectroscopic techniques such as Moessbauer, perturbed angular correlations (PAC) and emission channeling with the traditional non-radioactive techniques liked deep level transient spectroscopy (DLTS) and Hall effect measurements. Recently isotopes of elements, not available before, were successfully used in new PAC experiments, and the first photoluminescence (PL) measurements, where the element transmutation plays the essential role on the PL peak identification, have been performed. The scope of applications of radioactive ion beams for research in solid state physics will be enlarged in the near future, with the installation at ISOLDE of a post-accelerator device providing radioactive beams with energies ranging from a few keV up to a few MeV. (orig.)

New Horizon in Nuclear Physics and Astrophysics Using Radioactive Nuclear Beams

Science.gov (United States)

Tanihata, Isao

Beams of β- radioactive nuclei, having a lifetime as short as 1 ms have been used for studies of the nuclear structure and reaction relevant to nucleosynthesis in the universe. In nuclear-structure studies, decoupling of the proton and neutron distributions in nuclei has been discovered. The decoupling appeared as neutron halos and neutron skins on the surface of neutron-rich unstable nuclei. In astrophysics, reaction cross sections have been determined for many key reactions of nucleosynthesis involving short-lived nuclei in the initial and final states. One such important reaction, 13N+p → 14O +γ, has been studied using beams of unstable 13N nuclei. Such studies became possible after the invention of beams of radioactive nuclei in the mid-80's. Before that, the available ion beams were restricted to ions of stable nuclei for obvious reasons. In the next section the production method of radioactive beams is presented, then a few selected studies using radioactive beams are discussed in the following sections. In the last section, some useful properties of radioactive nuclei for other applications is shown.

Production of chemically reactive radioactive ion beams through on-line separation; Production de faisceaux d'ions radioactifs chimiquement reactifs par separation en ligne

Energy Technology Data Exchange (ETDEWEB)

Joinet, A

2003-10-01

The ISOL (isotope separation on line) allows the production of secondary radioactive ion beams through spallation or fragmentation or fission reactions that take place in a thick target bombarded by a high intensity primary beam. The challenge is to increase the intensity and purity of the radioactive beam. The optimization of the system target/source requires the right choice of material for the target by taking into account the stability of the material, its reactivity and the ionization method used. The target is an essential part of the system because radioactive elements are generated in it and are released more or less quickly. Tests have been made in order to select the best fitted material for the release of S, Se, Te, Ge and Sn. Materials tested as target filling are: ZrO{sub 2}, Nb, Ti, V,TiO{sub 2}, CeO{sub x}, ThO{sub 2}, C, ZrC{sub 4} and VC). Other molecules such as: COSe, COS, SeS, COTe, GeS, SiS, SnS have been studied to ease the extraction of recoil nuclei (Se, S, Te, Ge and Sn) produced inside the target.

Early results utilizing high-energy fission product gamma rays to detect fissionable material in cargo

International Nuclear Information System (INIS)

Slaughter, D.R.; Accatino, M.R.; Alford, O.J.; Bernstein, A.; Descalle, M.; Gosnell, T.B.; Hall, J.M.; Loshak, A.; Manatt, D.R.; McDowell, M.R.; Moore, T.L.; Petersen, D.C.; Pohl, B.A.; Pruet, J.A.; Prussin, S.G.

2004-01-01

Full text: A concept for detecting the presence of special nuclear material ( 235 U or 239 Pu) concealed in inter modal cargo containers is described. It is based on interrogation with a pulsed beam of 6-8 MeV neutrons and fission events are identified between beam pulses by their β-delayed neutron emission or β -delayed high-energy γ-radiation. The high-energy γ-ray signature is being employed for the first time. Fission product γ-rays above 3 MeV are distinct from natural radioactivity and from nearly all of the induced activity in a normal cargo. High-energy γ-radiation is nearly 10X more abundant than the delayed neutrons and penetrates even thick cargo's readily. The concept employs two large (8x20 ft) arrays of liquid scintillation detectors that have high efficiency for the detection of both delayed neutrons and delayed γ-radiation. Detector backgrounds and potential interferences with the fission signature radiation have been identified and quantified. This information, together with predicted signature strength, has been applied to the estimation of detection probability for the nuclear material and estimation of false alarm rates. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48

Simple estimate of fission rate during JCO criticality accident

Energy Technology Data Exchange (ETDEWEB)

Oyamatsu, Kazuhiro [Faculty of Studies on Contemporary Society, Aichi Shukutoku Univ., Nagakute, Aichi (Japan)

2000-03-01

The fission rate during JCO criticality accident is estimated from fission-product (FP) radioactivities in a uranium solution sample taken from the preparation basin 20 days after the accident. The FP radioactivity data are taken from a report by JAERI released in the Accident Investigation Committee. The total fission number is found quite dependent on the FP radioactivities and estimated to be about 4x10{sup 16} per liter, or 2x10{sup 18} per 16 kgU (assuming uranium concentration 278.9 g/liter). On the contrary, the time dependence of the fission rate is rather insensitive to the FP radioactivities. Hence, it is difficult to determine the fission number in the initial burst from the radioactivity data. (author)

Simple estimate of fission rate during JCO criticality accident

International Nuclear Information System (INIS)

Oyamatsu, Kazuhiro

2000-01-01

The fission rate during JCO criticality accident is estimated from fission-product (FP) radioactivities in a uranium solution sample taken from the preparation basin 20 days after the accident. The FP radioactivity data are taken from a report by JAERI released in the Accident Investigation Committee. The total fission number is found quite dependent on the FP radioactivities and estimated to be about 4x10 16 per liter, or 2x10 18 per 16 kgU (assuming uranium concentration 278.9 g/liter). On the contrary, the time dependence of the fission rate is rather insensitive to the FP radioactivities. Hence, it is difficult to determine the fission number in the initial burst from the radioactivity data. (author)

Development and validation of the aerosol transport module gamma-FP for evaluating radioactive fission product source terms in a VHTR

Energy Technology Data Exchange (ETDEWEB)

Yoon, Churl; Lim, Hong Sik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-12-15

Predicting radioactive fission product (FP) behaviors in the reactor coolant system and the containment of a nuclear power plant (NPP) is one of the major concerns in the field of reactor safety, since the amount of radioactive FP released into the environment during the postulated accident sequences is one of the major regulatory issues. Radioactive FPs circulating in the primary coolant loop and released into the containment are basically in the form of gas or aerosol. In this study, a multi-component and multi-sectional analysis module for aerosol fission products has been developed based on the MAEROS model, and the aerosol transport model has been developed and verified against an analytic solution. The deposition of aerosol FPs to the surrounding structural surfaces is modeled with recent research achievements. The developed aerosol analysis model has been successfully validated against the STORM SR-11 experimental data, which is International Standard Problem No. 40. Future studies include the development of the resuspension, growth, and chemical reaction models of aerosol fission products.

Moessbauer Effect applications using intense radioactive ion beams

International Nuclear Information System (INIS)

Taylor, R.D.

1990-01-01

The Moessbauer Effect is reviewed as a promising tool for a number of new solid state studies when used in combination with radioactive beam/implantation facilities. The usual Moessbauer Effect involves long-lived radioactive parents (days to years) that populate low-lying nuclear excited states that subsequently decay to the ground state. Resonant emission/absorption of recoil-free gamma rays from these states provide information on a number of properties of the host materials. Radioactive ion beams (RIB) produced on-line allow new Moessbauer nuclei to be studied where there is no suitable parent. The technique allows useful sources to be made having extremely low local concentrations. The ability to separate the beams in both Z and A should provide high specific activity ''conventional'' sources, a feature important in some applications such as Moessbauer studies in diamond anvil high pressure cells. Exotic chemistry is proposed using RIB and certain Krypton and Xenon Moessbauer isotopes

Separation of actinides and long-lived fission products from high-level radioactive wastes (a review)

International Nuclear Information System (INIS)

Kolarik, Z.

1991-11-01

The management of high-level radioactive wastes is facilitated, if long-lived and radiotoxic actinides and fission products are separated before the final disposal. Especially important is the separation of americium, curium, plutonium, neptunium, strontium, cesium and technetium. The separated nuclides can be deposited separately from the bulk of the high-level waste, but their transmutation to short-lived nuclides is a muchmore favourable option. This report reviews the chemistry of the separation of actinides and fission products from radioactive wastes. The composition, nature and conditioning of the wastes are described. The main attention is paid to the solvent extraction chemistry of the elements and to the application of solvent extraction in unit operations of potential partitioning processes. Also reviewed is the behaviour of the elements in the ion exchange chromatography, precipitation, electrolysis from aqueous solutions and melts, and the distribution between molten salts and metals. Flowsheets of selected partitioning processes are shown and general aspects of the waste partitioning are shortly discussed. (orig.) [de

Coulex fission of 234U, 235U, 237Np, and 238Np studied within the SOFIA experimental program

International Nuclear Information System (INIS)

Martin, Julie-Fiona

2014-01-01

SOFIA (Studies On FIssion with Aladin) is an experimental project which aims at systematically measuring the fission fragments' isotopic yields as well as their total kinetic energy, for a wide variety of fissioning nuclei. The PhD work presented in this dissertation takes part in the SOFIA project, and covers the fission of nuclei in the region of the actinides: 234 U, 235 U, 237 Np and 238 Np. The experiment is led at the heavy-ion accelerator GSI in Darmstadt, Germany. This facility provides intense relativistic primary beam of 238 U. A fragmentation reaction of the primary beam permits to create a secondary beam of radioactive ions, some of which the fission is studied. The ions of the secondary beam are sorted and identified through the FR-S (Fragment Separator), a high resolution recoil spectrometer which is tuned to select the ions of interest.The selected - fissile - ions then fly further to Cave-C, an experimental area where the fission experiment itself takes place. At the entrance of the cave, the secondary beam is excited by Coulomb interaction when flying through an target; the de-excitation process involves low-energy fission. Both fission fragments fly forward in the laboratory frame, due to the relativistic boost inferred from the fissioning nucleus.A complete recoil spectrometer has been designed and built by the SOFIA collaboration in the path of the fission fragments, around the existing ALADIN magnet. The identification of the fragments is performed by means of energy loss, time of flight and deviation in the magnet measurements. Both fission fragments are fully (in mass and charge) and simultaneously identified.This document reports on the analysis performed for (1) the identification of the fissioning system, (2) the identification of both fission fragments, on an event-by-event basis, and (3) the extraction of fission observables: yields, TKE, total prompt neutron multiplicity. These results, concerning the actinides, are discussed, and

Accelerator complex for a radioactive ion beam facility at ATLAS

International Nuclear Information System (INIS)

Nolen, J.A.

1995-01-01

Since the superconducting heavy ion linac ATLAS is an ideal post-accelerator for radioactive beams, plans are being developed for expansion of the facility with the addition of a driver accelerator, a production target/ion source combination, and a low q/m pre-accelerator for radioactive ions. A working group including staff from the ANL Physics Division and current ATLAS users are preparing a radioactive beam facility proposal. The present paper reviews the specifications of the accelerators required for the facility

Measurement of nuclear cross sections using radioactive beams

International Nuclear Information System (INIS)

Lizcano, D.; Aguilera, E.F.; Martinez Q, E.

1999-01-01

One of the main applications of the production and use of nuclear radioactive beams is the measurement of nuclear cross sections. In this work is used a 6 He nuclear radioactive beam (β emitting with half life 806.7 ms) for the study of the reaction 6 + 209 Bi which could have several products. This investigation was realized in collaboration with the personnel of the Nuclear Structure laboratory at the University of Notre Dame (U.S.A.) and the National institute of Nuclear Research and CONACyT by Mexico. (Author)

Recent results on reactions with radioactive beams at RIBRAS (Radioactive Ion Beams in Brazil)

Science.gov (United States)

Lépine-Szily, A.; Lichtenthäler, R.; Guimarães, V.; Arazi, A.; Barioni, A.; Benjamim, E. A.; de Faria, P. N.; Descouvemont, P.; Gasques, L. R.; E; Leistenschneider; Mendes, D. R., Jr.; Morais, M. C.; Morcelle, V.; Moro, A. M.; Pampa Condori, R.; Pires, K. C. C.; Rodriguez-Gallardo, M.; Scarduelli, V.; Shorto, J. M. B.; Zamora, J. C.

2015-04-01

We present a quick description of RIBRAS (Radioactive Ion beams in Brazil), which is a superconducting double solenoid system, installed at the Pelletron Laboratory of the University of São Paulo and extends the capabilities of the original Pelletron Tandem Accelerator of 8MV terminal voltage (8UD) by producing secondary beams of unstable nuclei. The experimental program of the RIBRAS covers the study of elastic and inelastic scattering with the objective to study the interaction potential and the reaction mechanisms between weakly bound (RIB) and halo (6He and 8B) projectiles on light, medium and heavy mass targets. With highly purified beams, the study of resonant elastic scattering and resonant transfer reactions, using inverse kinematics and thick targets, have also been included in our recent experimental program.

Holifield Radioactive Ion Beam Facility Development and Status

CERN Document Server

Tatum, Alan

2005-01-01

The Holifield Radioactive Ion Beam Facility (HRIBF) is a national user facility dedicated to nuclear structure, reactions, and nuclear astrophysics research with radioactive ion beams (RIBs) using the isotope separator on-line (ISOL) technique. An integrated strategic plan for physics, experimental systems, and RIB production facilities have been developed and implementation of the plan is under way. Specific research objectives are defined for studying the nature of nucleonic matter, the origin of elements, solar physics, and synthesis of heavy elements. Experimental systems upgrade plans include new detector arrays and beam lines, and expansion and upgrade of existing devices. A multifaceted facility expansion plan includes a $4.75M High Power Target Laboratory (HPTL), presently under construction, to provide a facility for testing new target materials, target geometries, ion sources, and beam preparation techniques. Additional planned upgrades include a second RIB production system (IRIS2), an external axi...

Spallation reaction study for fission products in nuclear waste: Cross section measurements for {sup 137}Cs and {sup 90}Sr on proton and deuteron

Energy Technology Data Exchange (ETDEWEB)

Wang, H., E-mail: wanghe@ribf.riken.jp [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Otsu, H.; Sakurai, H.; Ahn, D.S. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Aikawa, M. [Faculty of Science, Hokkaido University, Sapporo 060-0810 (Japan); Doornenbal, P.; Fukuda, N.; Isobe, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Kawakami, S. [Department of Applied Physics, University of Miyazaki, Miyazaki 889-2192 (Japan); Koyama, S. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Kubo, T.; Kubono, S.; Lorusso, G. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Maeda, Y. [Department of Applied Physics, University of Miyazaki, Miyazaki 889-2192 (Japan); Makinaga, A. [Graduate School of Medicine, Hokkaido University, North-14, West-5, Kita-ku, Sapporo 060-8648 (Japan); Momiyama, S. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Nakano, K. [Department of Advanced Energy Engineering Science, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Niikura, M. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Shiga, Y. [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Söderström, P.-A. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); and others

2016-03-10

We have studied spallation reactions for the fission products {sup 137}Cs and {sup 90}Sr for the purpose of nuclear waste transmutation. The spallation cross sections on the proton and deuteron were obtained in inverse kinematics for the first time using secondary beams of {sup 137}Cs and {sup 90}Sr at 185 MeV/nucleon at the RIKEN Radioactive Isotope Beam Factory. The target dependence has been investigated systematically, and the cross-section differences between the proton and deuteron are found to be larger for lighter spallation products. The experimental data are compared with the PHITS calculation, which includes cascade and evaporation processes. Our results suggest that both proton- and deuteron-induced spallation reactions are promising mechanisms for the transmutation of radioactive fission products.

Present and future radioactive beam studies at GANIL. From SISSI to SPIRAL

International Nuclear Information System (INIS)

Guerreau, D.

1996-01-01

The present status of radioactive beam developments at GANIL is discussed. The emphasis is put on the construction of the new SPIRAL radioactive beam facility presently underway and of the main trends in physics. (author)

Nuclear astrophysics with radioactive beams

International Nuclear Information System (INIS)

Bertulani, C.A.; Gade, A.

2010-01-01

The quest to comprehend how nuclear processes influence astrophysical phenomena is driving experimental and theoretical research programs worldwide. One of the main goals in nuclear astrophysics is to understand how energy is generated in stars, how elements are synthesized in stellar events and what the nature of neutron stars is. New experimental capabilities, the availability of radioactive beams and increased computational power paired with new astronomical observations have advanced the present knowledge. This review summarizes the progress in the field of nuclear astrophysics with a focus on the role of indirect methods and reactions involving beams of rare isotopes.

Design of the radioactive ion beam facility at the LNS

International Nuclear Information System (INIS)

Migneco, E.; Alba, R.; Calabretta, L.; Ciavola, G.; Cuttone, G.; Di Giacomo, M.; Gammino, S.; Gmaj, P.; Moscatello, M.H.; Raia, G.

1992-01-01

At the Laboratorio Nazionale del Sud the existing 15 MV Tandem will be coupled to the Superconducting Cyclotron booster, which will provide light and heavy ion beams in the energy range 100-20 MeV/n. Using these beams, secondary radioactive beams can be produced by projectile fragmentation. A fragment separator will collect the secondary beam produced at energies near that of the projectile and deliver it into the experimental areas. The possibility of using an ECRIS source for the axial injection into the Cyclotron and producing radioactive ions on a thick source placed inside the Tandem preinjector is also discussed. (author) 7 refs.; 2 figs.; 1 tab

Yield calculations for a facility for short-lived nuclear beams

CERN Document Server

Jiang, C L; Gomes, I; Heinz, A M; Nolen, Jerry A; Rehm, K E; Savard, G; Schiffer, J P

2002-01-01

Yields for a broad range of radioactive nuclei produced by spallation reactions, neutron-induced fission, in-flight projectile fragmentation and in-flight fission have been calculated for beams of stable nuclei at energies of 100-1000 MeV/u. Calculations of cross-sections and yields, attenuation effects due to absorption, production from secondary reactions, and transport efficiencies for mass selection are discussed. Rare isotope yields as functions of bombarding energies for both reaccelerated and directly produced fast-fragmentation beams are presented. This information provides a foundation for a cost-effective design of a next generation rare isotope accelerator.

Production of and studies with secondary radioactive ion beams at Lise

International Nuclear Information System (INIS)

Mueller, A.C.

1990-01-01

The doubly achromatic spectrometer LISE, installed at GANIL has delivered secondary radioactive beams for the past 6 years. Essentially, it consists of by two dipole magnets selecting (in A/Z) and refocusing (achromatically) the projectile-like fragment-beams emitted at 0 0 . Important features of LISE and selected experimental results will be discussed. LISE was substantially upgraded, recently, by adding a Wien-filter, providing secondary radioactive beams of still increased intensity and isotopic purity. (6 figs)

Fundamental symmetries and astrophysics with radioactive beams

International Nuclear Information System (INIS)

Vogt, E.

1996-04-01

A major new initiative at TRIUMF pertains to the use of radioactive beams for astrophysics and for fundamental symmetry experiments. Some recent work is described in which the β-decay-followed by alpha particle emission of 16 N was used to find the resonance parameters dominating the alpha particle capture in 12 C and thus to find the astrophysical S-factor of this reaction which is of crucial importance for alpha-particle burning and the subsequent collapse of stars. In some work underway trapped neural atoms of radioactive potassium atoms will be used to study fundamental symmetries of the weak interactions. Trapping has been achieved and soon 38m K decay will be used to search for evidence of scalar interactions and 37 K decay to search for right-handed gauge-bosom interactions. Future experiments are planned to look for parity non-conservation in trapped francium atoms. This program is part of a revitalization for the TRIUMF laboratory accompanied by the construction of the radioactive beam facility (ISAC). (author)

Studies of Fission Fragment Rocket Engine Propelled Spacecraft

Science.gov (United States)

Werka, Robert O.; Clark, Rodney; Sheldon, Rob; Percy, Thomas K.

2014-01-01

The NASA Office of Chief Technologist has funded from FY11 through FY14 successive studies of the physics, design, and spacecraft integration of a Fission Fragment Rocket Engine (FFRE) that directly converts the momentum of fission fragments continuously into spacecraft momentum at a theoretical specific impulse above one million seconds. While others have promised future propulsion advances if only you have the patience, the FFRE requires no waiting, no advances in physics and no advances in manufacturing processes. Such an engine unequivocally can create a new era of space exploration that can change spacecraft operation. The NIAC (NASA Institute for Advanced Concepts) Program Phase 1 study of FY11 first investigated how the revolutionary FFRE technology could be integrated into an advanced spacecraft. The FFRE combines existent technologies of low density fissioning dust trapped electrostatically and high field strength superconducting magnets for beam management. By organizing the nuclear core material to permit sufficient mean free path for escape of the fission fragments and by collimating the beam, this study showed the FFRE could convert nuclear power to thrust directly and efficiently at a delivered specific impulse of 527,000 seconds. The FY13 study showed that, without increasing the reactor power, adding a neutral gas to the fission fragment beam significantly increased the FFRE thrust through in a manner analogous to a jet engine afterburner. This frictional interaction of gas and beam resulted in an engine that continuously produced 1000 pound force of thrust at a delivered impulse of 32,000 seconds, thereby reducing the currently studied DRM 5 round trip mission to Mars from 3 years to 260 days. By decreasing the gas addition, this same engine can be tailored for much lower thrust at much higher impulse to match missions to more distant destinations. These studies created host spacecraft concepts configured for manned round trip journeys. While the

Correlation between Asian Dust and Specific Radioactivities of Fission Products Included in Airborne Samples in Tokushima, Shikoku Island, Japan, Due to the Fukushima Nuclear Accident

International Nuclear Information System (INIS)

Sakama, M.; Nagano, Y.; Kitade, T.; Shikino, O.; Nakayama, S.

2014-01-01

Radioactive fission product 131 I released from the Fukushima Daiichi Nuclear Power Plants (FD-NPP) was first detected on March 23, 2011 in an airborne aerosol sample collected at Tokushima, Shikoku Island, located in western Japan. Two other radioactive fission products, 134 Cs and 137 Cs were also observed in a sample collected from April 2 to 4, 2011. The maximum specific radioactivities observed in this work were about 2.5 to 3.5 mBq×m -3 in a airborne aerosol sample collected on April 6. During the course of the continuous monitoring, we also made our first observation of seasonal Asian Dust and those fission products associated with the FDNPP accident concurrently from May 2 to 5, 2011. We found that the specific radioactivities of 134 Cs and 137 Cs decreased drastically only during the period of Asian Dust. And also, it was found that this trend was very similar to the atmospheric elemental concentration (ng×m -3 ) variation of stable cesium ( 133 Cs) quantified by elemental analyses using our developed ICP-DRC-MS instrument

Techniques to produce and accelerate radioactive ion beams

CERN Document Server

Penescu, Liviu Constantin; Lettry, Jacques; Cata-Danil, Gheorghe

The production and acceleration of the Radioactive Ion Beams (RIB) continues the long line of nuclear investigations started in the XIXth century by Pierre and Marie Curie, Henri Becquerel and Ernest Rutherford. The contemporary applications of the RIBs span a wide range of physics fields: nuclear and atomic physics, solid-state physics, life sciences and material science. ISOLDE is a world-leading Isotope mass-Separation On-Line (ISOL) facility hosted at CERN in Geneva for more than 40 years, offering the largest variety of radioactive ion beams with, until now, more than 1000 isotopes of more than 72 elements (with Z ranging from 2 to 88), with half-lives down to milliseconds and intensities up to 1011 ions/s. The post acceleration of the full variety of beams allows reaching final energies between 0.8 and 3.0 MeV/u. This thesis describes the development of a new series of FEBIAD (“Forced Electron Beam Induced Arc Discharge”) ion sources at CERN-ISOLDE. The VADIS (“Versatile Arc Discharge Ion Source�...

Detection systems for radioactive ion beams; Systeme de detection en ions radioactifs

Energy Technology Data Exchange (ETDEWEB)

Savajols, H

2002-07-01

Two main methods are used to produce radioactive ion beams: -) the ISOL method (isotope separation on-line) in which the stable beam interacts with a thick target, the reaction products diffuse outside the target and are transferred to a source where they are ionized, a mass separator and a post-accelerator drive the selected radioactive ions to the right energy; -) the in-flight fragmentation method in which the stable beam interacts with a thin target, the reaction products are emitted from the target with a restricted angular distribution and a velocity close to that of the incident beam, the experimenter has to take advantage from the reaction kinetics to get the right particle beam. Characteristic time is far longer with the ISOL method but the beam intensity is much better because of the use of a post-accelerator. In both cases, the beam intensity is lower by several orders of magnitude than in the case of a stable beam. This article presents all the constraints imposed by radioactive beams to the detection systems of the reaction products and gives new technical solutions according to the type of nuclear reaction studied. (A.C.)

Studies of short-lived products of spallation fission reactions at TRIUMF

CERN Document Server

Bischoff, G; D'Auria, J M; Dautet, H; Lee, J K P; Pate, B D; Wiesehahn, W

1976-01-01

The gas-jet recoil transport technique has been used to transport products from spallation and fission reactions from a target chamber to a shielded location for nuclear spectroscopic studies. These involve X- beta - gamma coincidence measurements and (shortly) time- of-flight mass spectroscopy. It has been deduced that the proton beam at present intensities has no appreciable effect on the ability of ethylene and other cluster-producing gases to transport radioactivity. Preliminary results will be presented for shortlived fission products from uranium, and for spallation products of iodine and argon. The latter were obtained from the bombardment of gas and aerosol targets mixed with the transporting gas in the target chamber, which appears to be a generally useful technique.

Radioactive Beam Measurements to Probe Stellar Explosions

Energy Technology Data Exchange (ETDEWEB)

Smith, Michael Scott [ORNL

2010-01-01

Unique beams of unstable nuclei from the Holi eld Radioactive Ion Beam Facility at Oak Ridge National Laboratory are being used to measure the thermonuclear reactions that occur in novae, X-ray bursts, and supernovae. The astrophysical impact of these measurements is determined by synergistic nuclear data evaluations and element synthesis calculations. Results of recent measurements and explosion simulations are brie y described, along with future plans and software research tools for the community.

The wastes of nuclear fission; Les dechets de la fission nucleaire

Energy Technology Data Exchange (ETDEWEB)

Doubre, H. [Paris-11 Univ., Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, IN2P3/CNRS, 91 - Orsay (France)

2005-07-01

In this paper the author presents the problems of the radioactive wastes generated by the nuclear fission. The first part devoted to the fission phenomenon explains the incident neutron energy and the target nuclei role. The second part devoted to the nuclear wastes sources presents the production of wastes upstream of the reactors, in the reactors and why these wastes are dangerous. The third part discusses the radioactive wastes management in France (classification, laws). The last part details the associated research programs: the radionuclides separation, the disposal, the underground storage, the transmutation and the thorium cycle. (A.L.B.)

Ion sources for initial use at the Holifield radioactive ion beam facility

International Nuclear Information System (INIS)

Alton, G.D.

1994-01-01

The Holifield Radioactive Ion Beam Facility (HRIBF) now under construction at the Oak Ridge National Laboratory will use the 25-MV tandem accelerator for the acceleration of radioactive ion beams to energies appropriate for research in nuclear physics; negative ion beams are, therefore, required for injection into the tandem accelerator. Because charge exchange is an efficient means for converting initially positive ion beams to negative ion beams, both positive and negative ion sources are viable options for use at the facility; the choice of the type of ion source will depend on the overall efficiency for generating the radioactive species of interest. A high-temperature version of the CERN-ISOLDE positive ion source has been selected and a modified version of the source designed and fabricated for initial use at the HRIBF because of its low emittance, relatively high ionization efficiencies and species versatility, and because it has been engineered for remote installation, removal and servicing as required for safe handling in a high-radiation-level ISOL facility. Prototype plasma-sputter negative ion sources and negative surfaceionization sources are also under design consideration for generating negative radioactive ion beams from high electron-affinity elements. A brief review of the HRIBF will be presented, followed by a detailed description of the design features, operational characteristics, ionization efficiencies, and beam qualities (emittances) of these sources

The nuclear fission

International Nuclear Information System (INIS)

Fiorentino, J.

1983-01-01

The nuclear fission process considering initially the formation of compound nucleus and finishing with radioactive decay of fission products is studied. The process is divided in three parts which consist of the events associated to the nucleus of intermediate transitional state, the scission configuration, and the phenomenum of post scission. (M.C.K.) [pt

Attachment behavior of fission products to solution aerosol

Energy Technology Data Exchange (ETDEWEB)

Takamiya, Koichi; Tanaka, Toru; Nitta, Shinnosuke; Itosu, Satoshi; Sekimoto, Shun; Oki, Yuichi; Ohtsuki, Tsutomu [Research Reactor Institute, Kyoto University, Osaka (Japan)

2016-12-15

Various characteristics such as size distribution, chemical component and radioactivity have been analyzed for radioactive aerosols released from Fukushima Daiichi Nuclear Power Plant. Measured results for radioactive aerosols suggest that the potential transport medium for radioactive cesium was non-sea-salt sulfate. This result indicates that cesium isotopes would preferentially attach with sulfate compounds. In the present work the attachment behavior of fission products to aqueous solution aerosols of sodium salts has been studied using a generation system of solution aerosols and spontaneous fission source of {sup 248}Cm. Attachment ratios of fission products to the solution aerosols were compared among the aerosols generated by different solutions of sodium salt. A significant difference according as a solute of solution aerosols was found in the attachment behavior. The present results suggest the existence of chemical effects in the attachment behavior of fission products to solution aerosols.

High-energy beams of radioactive nuclei and their biomedical applications

International Nuclear Information System (INIS)

Alpen, E.L.; Chatterjee, A.; Llacer, J.

1981-01-01

Several exploratory measurements have been conducted with radioactive beams to test the feasibility of using these beams to measure effective stopping power of heterogeneous media for heavy charged particles. Such measurements will provide direct information on the average electron density and average stopping number of a target with an unknown heterogeneous beam path. This information, once obtained with a suitable radioactive beam, can be used in equations to calculate the energy of any heavy particle of therapeutic choice so that the Bragg peak of the therapeutic beam can be placed on the tumor volume. A beam of high-energy heavy ions was collimated to a diameter of 1.58 cm (PEBA has a good positional accuracy as long as the beam diameter is less than 2 cm), and made to enter target materials (mixed or homogeneous) positioned between the detector banks and centered along the beam axis. Measurements have been made with 11 C and 19 Ne beams, but the short half-life of 19 Ne (19 sec) allows prompt repeated measurements, making that nucleus very interesting for these purposes. Only the results obtained with it are reported

Progress in fission product nuclear data

International Nuclear Information System (INIS)

Lammer, M.

1984-09-01

This is the tenth issue of a report series on Fission Product Data, which informs us about all the activities in this field, which are planned, ongoing, or have recently been completed. The types of activities included are measurements, compilations and evaluations of: fission product yields (neutron induced and spontaneous fission), neutron reaction cross sections of fission products, data related to the radioactive decay of fission products, delayed neutron data of fission products, lumped fission product data (decay heat, absorption, etc.). There is also a section with recent references relative to fission product nuclear data

Characterization of low energy radioactive beams using direct reactions

DEFF Research Database (Denmark)

Johansen, J.G.; Fraser, M.A.; Bildstein, V.

2013-01-01

We demonstrate a new technique to determine the beam structure of low energy radioactive beams using coincidence events from a direct reaction. The technique will be described and tested using Geant4 simulations. We use the technique to determine for the first time the width, divergence and energy...

Target conception for the Munich fission fragment accelerator

CERN Document Server

Maier, H J; Gross, M L; Grossmann, R; Kester, O; Thirolf, P

1999-01-01

For the new high-flux reactor FRM II, the fission fragment accelerator MAFF is under design. MAFF will supply intense mass-separated radioactive ion beams of very neutron-rich nuclei with energies around the Coulomb barrier. A central part of this accelerator is the ion source with the fission target, which is operated at a neutron flux of 1.5x10 sup 1 sup 4 cm sup - sup 2 s sup - sup 1. The target consists of typically 1 g of sup 2 sup 3 sup 5 U dispersed in a cylindrical graphite matrix, which is encapsulated in a Re container. To enable diffusion and extraction of the fission products, the target has to be maintained at a temperature of up to 2400 deg. C during operation. It has to stand this temperature for at least one reactor cycle of 1250 h. Comprehensive tests are required to study the long-term behaviour of the involved materials at these conditions prior to operation in the reactor. The present paper gives details of the target conception and the projected tests.

Condensed matter physics with radioactive ion beams

International Nuclear Information System (INIS)

Haas, H.

1996-01-01

An overview of the present uses of radioactive ion beams from ISOLDE for condensed matter research is presented. As simple examples of such work, tracer studies of diffusion processes with radioisotopes and blocking/channeling measurements of emitted particles for lattice location are discussed. Especially the application of nuclear hyperfine interaction techniques such as PAC or Moessbauer spectroscopy has become a powerful tool to study local electronic and structural properties at impurities. Recently, interesting information on impurity properties in semiconductors has been obtained using all these methods. The extreme sensitivity of nuclear techniques makes them also well suited for investigations of surfaces, interfaces, and biomolecules. Some ideas for future uses of high energy radioactive ion beams beyond the scope of the present projects are outlined: the study of diffusion in highly immiscible systems by deep implantation, nuclear polarization with the tilted-foil technique, and transmutation doping of wide-bandgap semiconductors. (orig.)

Correlation between Asian Dust and Specific Radioactivities of Fission Products Included in Airborne Samples in Tokushima, Shikoku Island, Japan, Due to the Fukushima Nuclear Accident

Energy Technology Data Exchange (ETDEWEB)

Sakama, M., E-mail: minorusakama@tokushima-u.ac.jp [Department of Radiological Science, Division of Biomedical Information Sciences, Institute of Health Biosciences, The University of Tokushima, Tokushima 770-8509 (Japan); Nagano, Y. [Department of Radiological Science, Division of Biomedical Information Sciences, Institute of Health Biosciences, The University of Tokushima, Tokushima 770-8509 (Japan); Kitade, T. [Department of Laboratory, M and S Instruments Inc., Osaka 532-0005 (Japan); Shikino, O. [Department of Inorganic Analysis, PerkinElmer Japan Co. Ltd., Yokohama 240-0005 (Japan); Nakayama, S. [Department of Nuclear Science, Institute of Socio-Arts and Sciences, The University of Tokushima, Tokushima 770-8502 (Japan)

2014-06-15

Radioactive fission product {sup 131}I released from the Fukushima Daiichi Nuclear Power Plants (FD-NPP) was first detected on March 23, 2011 in an airborne aerosol sample collected at Tokushima, Shikoku Island, located in western Japan. Two other radioactive fission products, {sup 134}Cs and {sup 137}Cs were also observed in a sample collected from April 2 to 4, 2011. The maximum specific radioactivities observed in this work were about 2.5 to 3.5 mBq×m{sup -3} in a airborne aerosol sample collected on April 6. During the course of the continuous monitoring, we also made our first observation of seasonal Asian Dust and those fission products associated with the FDNPP accident concurrently from May 2 to 5, 2011. We found that the specific radioactivities of {sup 134}Cs and {sup 137}Cs decreased drastically only during the period of Asian Dust. And also, it was found that this trend was very similar to the atmospheric elemental concentration (ng×m{sup -3}) variation of stable cesium ({sup 133}Cs) quantified by elemental analyses using our developed ICP-DRC-MS instrument.

Some thoughts on opportunities with reactions using radioactive beams

International Nuclear Information System (INIS)

Schiffer, J.P.

1990-01-01

I was asked to talk about the use of radioactive beams for nuclear reactions. My overall perspective is that the scientific justification for such studies must be done carefully. To go to the added complexity of radioactive beams one must clearly demonstrate the need for obtaining information about nuclear structure or processes, information that is not otherwise available. On the other hand, much of what we know about nuclear structure comes from nuclear reactions with stable nuclear beams and targets. While a certain amount of information about far from stability nuclei may be obtained from the study of their radioactive decays, this is limited. Our knowledge and understanding of nuclear structure comes from stable nuclei: energy levels, their spins and parties, and very importantly the matrix elements characterizing them. These are largely determined by reaction studies with normal stable nuclei. The extension of such studies to unstable nuclei, far from stability, may well hold qualitative surprises, or at the very least give a firmer basis to our understanding of nuclear structure. Perhaps it is a matter of taste, but if one wishes to start on this endeavor then it is best to begin with simple, easily accessible features. The ''simplest'' nuclei are the ones that form doubly-closed shells and the easiest features to explore initially are the single-particle states and the collective excitations that one can build on these. I would like to emphasize that a unique facility for this type of study is about to come into operation in Darmstadt where the ESR storage ring will capture radioactive beams from fragmentation products and cool them to useful energies for reaction studies

HAC and fission reactors

International Nuclear Information System (INIS)

Fujiwara, I.; Moriyama, H.; Tachikawa, E.

1984-01-01

In the fission process, newly formed fission products undergo hot atom reactions due to their energetic recoil and abnormal positive charge. The hot atom reactions of the fission products are usually accompanied by secondary effects such as radiation damage, especially in condensed phase. For reactor safety it is valuable to know the chemical behaviour and the release behaviour of these radioactive fission products. Here, the authors study the chemical behaviour and the release behaviour of the fission products from the viewpoint of hot atom chemistry (HAC). They analyze the experimental results concerning fission product behaviour with the help of the theories in HAC and other neighboring fields such as radiation chemistry. (Auth.)

National Centre for Radioactive Ion Beams (NCRIB)

International Nuclear Information System (INIS)

Chintalapudi, S.N.

1999-01-01

Radioactive Ion (nuclear) Beams have become prolific recently. Nuclear physics and associated subjects have staged a comeback to almost the beginning with the advent of RIB. A dedicated National Centre for RIB (NCRIB) proposed, discussed at several forums and under serious consideration is described

The ISOLDE Facility: Radioactive beams at CERN

CERN Multimedia

CERN. Geneva

2008-01-01

Some of the experimental techniques used will be introduced; more focus will be put on what physics questions can be answered by using radioactive beams. A brief overview is given of the present and future European developments in this rapidly evolving field. Prerequisite knowledge: none

Radioactive ion beam facilities in Europe

International Nuclear Information System (INIS)

Blumenfeld, Y.

2008-01-01

The past two decades have seen extraordinarily rapid development of radioactive beam physics throughout the world and in particular in Europe. The important scientific advances have stemmed from a large number of facilities. Previously existing stable beam machines have been adapted to produce rare isotope beams and dedicated facilities have come on-line. This talk gives an overview of the present European installations highlighting their complementary nature. The European roadmap calls for the construction of two next generation facilities: FAIR making use of projectile fragmentation and EURISOL based on the ISOL technique. The future FAIR facility will be described and the path towards EURISOL presented in the light of the construction of 'intermediate' generation facilities SPIRAL2, HIE ISOLDE and SPES and results from the ongoing EURISOL Design Study.

High resolution line for secondary radioactive beams at the U400M cyclotron

International Nuclear Information System (INIS)

Rodin, A.M.; Sidorchuk, S.I.; Stepantsov, S.V.

1996-01-01

For implementation of an experimental program for studying nuclear reactions with radioactive ion beams in the energy domain of 20 through 80 MeV · A the high resolution beam line ACCULINNA was put into commissioning on a primary beam line of the JINR U-400M cyclotron. By means of nuclear fragmentation of the 14 N beam with the energy of 51 MeV · A on the 170 mg/cm 2 carbon target radioactive beams of 6 He, 8 He and 8 B were obtained. Possibilities of further development of the set-up are discussed. 6 refs., 7 figs., 2 tabs

Photonuclear fission with quasimonoenergetic electron beams from laser wakefields

International Nuclear Information System (INIS)

Reed, S. A.; Chvykov, V.; Kalintchenko, G.; Matsuoka, T.; Rousseau, P.; Yanovsky, V.; Vane, C. R.; Beene, J. R.; Stracener, D.; Schultz, D. R.; Maksimchuk, A.

2006-01-01

Recent advancements in laser wakefield accelerators have resulted in the generation of low divergence, hundred MeV, quasimonoenergetic electron beams. The bremsstrahlung produced by these highly energetic electrons in heavy converters includes a large number of MeV γ rays that have been utilized to induce photofission in natural uranium. Analysis of the measured delayed γ emission demonstrates production of greater than 3x10 5 fission events per joule of laser energy, which is more than an order of magnitude greater than that previously achieved. Monte Carlo simulations model the generated bremsstrahlung spectrum and compare photofission yields as a function of target depth and incident electron energy

Storage ion trap of an 'In-Flight Capture' type for precise mass measurement of radioactive nuclear reaction products and fission fragments

International Nuclear Information System (INIS)

Tarantin, N.I.

2001-01-01

Data on nuclear masses provide a basis for creating and testing various nuclear models. A tandem system of FLNR comprised of the U-400M cyclotron, the COMBAS magnetic separator and the mass-spectrometric ion trap of an 'in-flight capture' type is considered as a possible complex for producing of the short-lived nuclei in fragmentation reactions by heavy ions and for precise mass measurement of these nuclei. The plan of scientific and technical FLNR research includes a project DRIBs for producing beams of accelerated radioactive nuclear reaction products and photofission fragments. This project proposes also precise mass measurements of the fission fragment with the help of the ion trap. The in-flight entrance of the ions and their capture in the mass-spectrometric ion trap using the monochromatizing degrader, the static electric and magnetic fields and a new invention, a magnetic unidirectional transporting ventil, is considered

Radioactive Emissions from Fission-Based Medical Isotope Production and Their Effect on Global Nuclear Explosion Detection

International Nuclear Information System (INIS)

Bowyer, T.; Saey, P.

2015-01-01

The use of medical isotopes, such as Tc-99m, is widespread with over 30 million procedures being performed every year, but the fission-based production of isotopes used for medical procedures causes emissions into the environment. This paper will show that gaseous radioactive isotopes of xenon, such as Xe-133, are released in high quantities, because they have a high fission cross section and they are difficult to scrub from the processes used to produce the medical isotopes due to their largely unreactive nature. Unfortunately, the reasons that large amounts of radioactive xenon isotopes are emitted from isotope production are the same as those that make these isotopes the most useful isotopes for the detection of underground nuclear explosions. Relatively recently, the nuclear explosion monitoring community has established a provisional monitoring network for the Comprehensive Nuclear-Test-Ban Treaty (CTBT) that includes radioactive xenon monitoring as a major component. This community has discovered that emissions from medical isotope production present a more serious problem to nuclear explosion monitoring than thought when the network was first conceived. To address the growing problem, a group of scientists in both the monitoring and the isotope production communities have come together to attempt to find scientific and pragmatic ways to address the emissions problems, recognizing that medical isotope production should not be adversely affected, while monitoring for nuclear explosions should remain effective as isotope production grows, changes, and spreads globally. (author)

The usage of electron beam to produce radio isotopes through the uranium fission by γ-rays and neutrons

International Nuclear Information System (INIS)

Bunatyan, G.G.; Nikolenko, V.G.; Popov, A.V.

2010-01-01

We treat the production of desirable radio isotopes due to the 238 U photo-fission by the bremsstrahlung induced in converter by an initial electron beam provided by a linear electron accelerator. We consider as well the radio isotope production through the 238 U fission by the neutrons that stem in the 238 U sample irradiated by that bremsstrahlung. The yield of the most applicable radio isotope 99 Mo is calculated. We correlate the findings acquired in the work presented with those obtained by treating the nuclear photo-neutron reaction. Menace of the plutonium contamination of an irradiated uranium sample because of the neutron capture by 238 U is considered. As we get convinced, the photo-neutron production of radio isotopes proves to be more practicable than the production by the uranium photo- and neutron-fission. Both methods are certain to be brought into action due to usage of the electron beam provided by modern linear accelerators

Charge breeding of stable and radioactive ion beams with EBIS/T devices

CERN Document Server

Kester, Oliver; Becker, R

2004-01-01

Radioactive ion beams (RIBs) are an important tool for experiments at the foremost frontier of nuclear physics. The quasi-continuous radioactive beams from target ion sources of RIB-facilities have to be accelerated to energies at and beyond the Coulomb barrier. An efficient acceleration requires a suitable A/q of the ions determined by the accelerator design, which can be reached via the stripping method or by using a charge state breeder like the REX-ISOLDE system. In order to get comparable efficiencies for a charge state breeder with the stripping scheme, the breeding efficiency in one charge state has to be optimized by narrowing the charge state distribution. In addition good beam quality and thus small emittances are required to achieve best transmission in the following accelerator, which is mandatory for high intensity RIBs. For EBIS/T devices the maximum intensity of the radioactive ion beam is a critical issue, and high current EBIS/T devices will be necessary to deal with intensities of second gen...

Fifth International Conference on Fission and Properties of Neutron-Rich Nuclei

CERN Document Server

Ramayya, A V; ICFN5

2014-01-01

These proceedings are the fifth in the series of International Conferences covering fission and properties of neutron-rich nuclei, which are at the forefront of nuclear research. The time interval of 5 years between each conference allows for significant new results to be achieved. Recently, world leaders in theory and experiments in research and the development of new facilities for research presented their latest results in areas such as synthesis of superheavy elements, new facilities for and recent results with radioactive ion beams, structure of neutron-rich nuclei, nuclear fission process, fission yields and nuclear astrophysics. This book is a major source of the latest research in these areas and plans for the future. The conference brought together a unique group of over 100 speakers including leaders from the major nuclear laboratories in Canada, China, France, Finland, Germany, Italy, Japan, Russia, Switerzland and the US along with leading research scientists from around the world.

Laser spectroscopy of radioactive beams

International Nuclear Information System (INIS)

Otten, E.W.

1983-01-01

The problem of using the laser spectroscopy in investigations radioactive beams is considered. The main attention is payed to the isotope shift of nuclear charge radii delta 2 >. The general trend of delta 2 > is discussed. Predictions for delta>r 2 < in the framework of the droplet model are given. It is noted that two parameter interpretation of the isotope shift based on the droplet model works the better, the further the distance spans and the clearer the nuclear structure is

Neutron-induced fission fragment angular distribution at CERN n TOF: The Th-232 case

CERN Document Server

Tarrio, Diego; Paradela, Carlos

This thesis work was done in the frame of the study of the neutron-induced fission of actinides and subactinides at the CERN n TOF facility using a fast Parallel Plate Avalanche Counters (PPACs) setup. This experimental setup provide us with an intense neutron beam with a white spectrum from thermal to 1 GeV and with an outstanding high resolution provided by its flight path of 185 m. In our experiment, fission events were identified by detection of both fission fragments in time coincidence in the two PPAC detectors flanking the corresponding target. This technique allowed us to discriminate the fission events from the background produced by α disintegration of radioactive samples and by particles produced in spallation reactions. Because PPAC detectors are insensitive to the γ flash, it is possible to reach energies as high as 1 GeV. The stripped cathodes provide the spatial position of the hits in the detectors, so that the emission angle of the fission fragments can be measured. Inside the reaction cham...

The radioactive ion beams facility project for the legnaro laboratories

Science.gov (United States)

Tecchio, Luigi B.

1999-04-01

In the frame work of the Italian participation to the project of a high intensity proton facility for the energy amplifier and nuclear waste transmutations, LNL is involving in the design and construction of prototypes of the injection system of the 1 GeV linac that consists of a RFQ (5 MeV, 30 mA) followed by a 100 MeV linac. This program has been already financially supported and the work is actually in progress. In this context, the LNL has been proposed a project for the construction of a second generation facility for the production of radioactive ion beams (RIBs) by using the ISOL method. The final goal consists in the production of neutron rich RIBs with masses ranging from 80 to 160 by using primary beams of protons, deuterons and light ions with energy of 100 MeV and 100 kW power. This project is proposed to be developed in about 10 years from now and intermediate milestones and experiments are foreseen and under consideration for the next INFN five year plan (1999-2003). In such period of time is proposed the construction of a proton/deuteron accelerator of 10 MeV energy and 10 mA current, consisting of a RFQ (5 MeV, 30 mA) and a linac (10 MeV, 10 mA), and of a neutron area dedicated to the RIBs production, to the BNCT applications and to the neutron physics. Some remarks on the production methods will be presented. The possibility of producing radioisotopes by means of the fission induced by neutrons will be investigated and the methods of production of neutrons will be discussed.

Radioactive beam studies of cosmological interest

International Nuclear Information System (INIS)

Sale, K.E.; Boyd, R.N.; Mathews, G.J.; Corn, B.P.; Islam, M.S.

1989-01-01

Experimental efforts by the LLNL/Ohio State radioactive ion beam collaboration are described. We are presently focusing on some reactions which are of great importance in the newly proposed inhomogeneous big bang cosmological models. Specifically we are using our system to make beams of 8 Li for measurements of the 8 Li(d, n) 9 Be and 8 Li(α, n) 11 B cross-sections. These are the key reactions which determine the production of heavy (A > 12) elements during the era of big bang nucleosynthesis, and thus the initial composition of stars and subsequent stellar isotope production. Plans for future experiments, including the measurement of the 7 Be(p, γ) 8 B cross section will be discussed. (orig.)

Amount, disposal and relative toxicity of long-lived fission products and actinides in the radioactive wastes of the nuclear fuel cycles

International Nuclear Information System (INIS)

Haug, H.O.

1975-11-01

A review is presented on the magnitude of the long-term problems of radioactive wastes from the nuclear power industry of the FRG (and Western Europe). The production of long-lived fission products and actinides has been calculated for several fuel types of the uranium-plutonium and thorium-uranium fuel cycles and related to a prediction of the development and share of LWR, FBR and HTGR. The quantities and concentrations of actinides, the radioactivity and relative toxicity index of the wastes of reprocessing (and fuel refabrication) and their changes by radioactive decay are presented. The radiotoxicity of the nuclide inventory of the solidified high-level wastes have been compared with naturally occuring uranium ores. On the long term (>10 3 years) the radiotoxicity level of the total area of the final repository in deep geological formation does not result in a significantly higher radiotoxicity level than an uranium ore deposit of low uranium content. Also discussed have been the chemical separation of the actinides from high-level wastes and recycling in fission reactors. (orig.) [de

The Holifield Radioactive Ion Beams Facility (HRIBF) - getting ready to do experiments

International Nuclear Information System (INIS)

Shapira, D.; Lewis, T.A.

1998-01-01

The conversion of the HHIRF facility to a Radioactive Ion Beam facility started in 1994. In this ISOL type facility the Cyclotron has been re-fitted as a driver providing high intensity proton beams which react with the target from which the radioactive products are extracted and then accelerated in the Tandem Electrostatic Accelerator to the desired energy for nuclear science studies. Facilities for nuclear physics experiments are at different stages of development: A Recoil Mass Spectrometer (RMS) with a complement of detectors at the focal plane and around the target is used primarily for nuclear structure studies. A large recoil separator combining velocity and momentum selection, with its complement of focal plane detectors, will be dedicated to measurements relevant to nuclear astrophysics. The Enge Split Pole spectrograph is being re-fitted for operation in a gas filled mode, making it a more versatile tool for nuclear reaction studies. With the new experimental equipment being commissioned and the prospects of running experiments with low intensity radioactive beams a significant effort to develop equipment for beam diagnostics is underway. Some of the efforts and results in developing beam diagnostic tools will be described

Electroplating method for producing ultralow-mass fissionable deposits

International Nuclear Information System (INIS)

Ruddy, F.H.

1989-01-01

A method for producing ultralow-mass fissionable deposits for nuclear reactor dosimetry is described, including the steps of holding a radioactive parent until the radioactive parent reaches secular equilibrium with a daughter isotope, chemically separating the daughter from the parent, electroplating the daughter on a suitable substrate, and holding the electroplated daughter until the daughter decays to the fissionable deposit

Accelerator development for a radioactive beam facility based on ATLAS

International Nuclear Information System (INIS)

Shepard, K. W.

1998-01-01

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

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.

Measurement of Fission Product Yields from Fast-Neutron Fission

Science.gov (United States)

Arnold, C. W.; Bond, E. M.; Bredeweg, T. A.; Fowler, M. M.; Moody, W. A.; Rusev, G.; Vieira, D. J.; Wilhelmy, J. B.; Becker, J. A.; Henderson, R.; Kenneally, J.; Macri, R.; McNabb, D.; Ryan, C.; Sheets, S.; Stoyer, M. A.; Tonchev, A. P.; Bhatia, C.; Bhike, M.; Fallin, B.; Gooden, M. E.; Howell, C. R.; Kelley, J. H.; Tornow, W.

2014-09-01

One of the aims of the Stockpile Stewardship Program is a reduction of the uncertainties on fission data used for analyzing nuclear test data [1,2]. Fission products such as 147Nd are convenient for determining fission yields because of their relatively high yield per fission (about 2%) and long half-life (10.98 days). A scientific program for measuring fission product yields from 235U,238U and 239Pu targets as a function of bombarding neutron energy (0.1 to 15 MeV) is currently underway using monoenergetic neutron beams produced at the 10 MV Tandem Accelerator at TUNL. Dual-fission chambers are used to determine the rate of fission in targets during activation. Activated targets are counted in highly shielded HPGe detectors over a period of several weeks to identify decaying fission products. To date, data have been collected at neutron bombarding energies 4.6, 9.0, 14.5 and 14.8 MeV. Experimental methods and data reduction techniques are discussed, and some preliminary results are presented.

Physics with radioactive nuclear beams

International Nuclear Information System (INIS)

Boyd, R.N.; Tanihata, I.

1992-01-01

Recently developed facilities allow a wide range of new investigations of the reactions and properties of short-lived nuclei. These studies may help to solve puzzles of nuclear structure and the Big Bang. The purpose of nuclear physics is to measure properties of specific nuclides and infer from them global properties common to all nuclides. One goal, for example, is to understand nuclear sizes and matter distributions in terms of basic nuclear forces. Another is to understand the variation throughout the periodic table of the dominant quantum states, which are known as the open-quotes nuclear shell modelclose quotes states and are characterized, much as are atomic states, by a principal quantum number and by orbital and total angular momentum quantum numbers. In turn other nuclear phenomena, such as the collective excitations known as giant resonances, can be understood in terms of the shell-model configurations and basic nuclear parameters. Radioactive nuclear beam studies of reactions of short-lived nuclides have already yielded results with important ramifications in both nuclear physics and astrophysics. Nuclear physicists expect unstable nuclides to exhibit unusual structures or features that may test their understanding of known nuclear phenomena at extreme conditions, and perhaps even to reveal previously unknown nuclear phenomena, Astrophysicists, for their part, have known for several decades that processes in both Big Bang nucleosynthesis and stellar nucleosynthesis involve short-lived nuclides. Indeed, the original motivation for developing radioactive nuclear beams was astrophysical. 25 refs., 7 figs

Physics with radioactive nuclear beams

International Nuclear Information System (INIS)

Boyd, R.N.

1995-01-01

Recently developed facilities allow a wide range of new investigations of the reactions and properties of short-lived nuclei. These studies may help to solve puzzles of nuclear structure and the Big Bang. The purpose of nuclear physics is to measure properties of specific nuclides and infer from them global properties common to all nuclides, for example, is to understand nuclear sizes and matter distributions in terms of basic nuclear forces. Another is to understand the variation throughout the periodic table of the dominant quantum states, which are known as the open-quotes nuclear shell model close quotes states and are characterized, much as are atomic states, by a principal quantum number and by orbital and total angular momentum quantum numbers. In turn other nuclear phenomena, such as the collective excitations known as giant resonances, can be understood in terms of the shell-model configurations and basic nuclear parameters. Radioactive nuclear beam studies of reactions of short-lived nuclides have already yielded results with important ramifications in both nuclear physics and astrophysics. Nuclear physicists expect unstable nuclides to exhibit unusual structures or features that may test their understanding of known nuclear phenomena at extreme conditions, and perhaps even to reveal previously unknown nuclear phenomena, Astrophysicists, for their part, have known for several decades that processes in both Big Bang nucleosynthesis and stellar nucleosynthesis involve short-lived nuclides. Indeed, the original motivation for developing radioactive nuclear beams was astrophysical. (author). 25 refs., 7 figs

Precision Gamma-Ray Branching Ratios for Long-Lived Radioactive Nuclei

Energy Technology Data Exchange (ETDEWEB)

Tonchev, Anton [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-10-19

Many properties of the high-energy-density environments in nuclear weapons tests, advanced laser-fusion experiments, the interior of stars, and other astrophysical bodies must be inferred from the resulting long-lived radioactive nuclei that are produced. These radioactive nuclei are most easily and sensitively identified by studying the characteristic gamma rays emitted during decay. Measuring a number of decays via detection of the characteristic gamma-rays emitted during the gamma-decay (the gamma-ray branching ratio) of the long-lived fission products is one of the most straightforward and reliable ways to determine the number of fissions that occurred in a nuclear weapon test. The fission products ¹⁴⁷Nd, ¹⁴⁴Ce, ¹⁵⁶Eu, and certain other long-lived isotopes play a crucial role in science-based stockpile stewardship, however, the large uncertainties (about 8%) on the branching ratios measured for these isotopes are currently limiting the usefulness of the existing data [1,2]. We performed highly accurate gamma-ray branching-ratio measurements for a group of high-atomic-number rare earth isotopes to greatly improve the precision and reliability with which the fission yield and reaction products in high-energy-density environments can be determined. We have developed techniques that take advantage of new radioactive-beam facilities, such as DOE's CARIBU located at Argonne National Laboratory, to produce radioactive samples and perform decay spectroscopy measurements. The absolute gamma-ray branching ratios for ¹⁴⁷Nd and ¹⁴⁴Ce are reduced <2% precision. In addition, high-energy monoenergetic neutron beams from the FN Tandem accelerator in TUNL at Duke University was used to produce ¹⁶⁷Tm using the ¹⁶⁹Tm(n,3n) reaction. Fourtime improved branching ratio of ¹⁶⁷Tm is used now to measure reaction-in-flight (RIF) neutrons from a burning DT capsule at NIF [10]. This represents the

Submicro and Nano Structured Porous Materials for the Production of High-Intensity Exotic Radioactive Ion Beams

CERN Document Server

Fernandes, Sandrina; Stora, Thierry

2010-01-01

ISOLDE, the CERN Isotope Separator On-line DEvice is a unique source of low energy beams of radioactive isotopes - atomic nuclei that have too many or too few neutrons to be stable. The facility is like a small ‘chemical factory’, giving the possibility of changing one element to another, by selecting the atomic mass of the required isotope beam in the mass separator, rather as the ‘alchemists’ once imagined. It produces a total of more than 1000 different isotopes from helium to radium, with half-lives down to milliseconds, by impinging a 1.4 GeV proton beam from the Proton Synchrotron Booster (PSB) onto special targets, yielding a wide variety of atomic fragments. Different components then extract the nuclei and separate them according to mass. The post-accelerator REX (Radioactive beam EXperiment) at ISOLDE accelerates the radioactive beams up to 3 MeV/u for many experiments. A wide international user radioactive ion beam (RIB) community investigates fundamental aspects of nuclear physics, particle...

Beam Dynamics Design Studies of a Superconducting Radioactive Ion Beam Post-accelerator

CERN Document Server

Fraser, MA; Pasini, M

2011-01-01

The HIE-ISOLDE project at CERN proposes a superconducting upgrade to increase the energy range and quality of the radioactive ion beams produced at ISOLDE, which are currently post- accelerated by the normal conducting REX linac. The specification and design choices for the HIE-ISOLDE linac are outlined along with a comprehensive beam dynamics study undertaken to understand and mitigate the sources of beam emittance dilution. The dominant cause of transverse emittance growth was attributed to the coupling between the transverse and longitudinal motions through the phase dependence of the rf defocusing force in the accelerating cavities. A parametric resonance induced by the coupling was observed and its excitation surveyed as a function of trans- verse phase advance using numerical simulations and analytic models to understand and avoid the regions of transverse beam instability. Other sources of emittance growth were studied and where necessary ameliorated, including the beam steering force in the quarter-wa...

The beam diagnostic instruments in Beijing radioactive ion-beam facilities isotope separator on-line

International Nuclear Information System (INIS)

Ma, Y.; Cui, B.; Ma, R.; Tang, B.; Chen, L.; Huang, Q.; Jiang, W.

2014-01-01

The beam diagnostic instruments for Beijing Radioactive Ion-beam Facilities Isotope Separator On-Line are introduced [B. Q. Cui, Z. H. Peng, Y. J. Ma, R. G. Ma, B. Tang, T. Zhang, and W. S. Jiang, Nucl. Instrum. Methods 266, 4113 (2008); T. J. Zhang, X. L. Guan, and B. Q. Cui, in Proceedings of APAC 2004, Gyeongju, Korea, 2004, http://www.jacow.org , p. 267]. For low intensity ion beam [30–300 keV/1 pA–10 μA], the beam profile monitor, the emittance measurement unit, and the analyzing slit will be installed. For the primary proton beam [100 MeV/200 μA], the beam profile scanner will be installed. For identification of the nuclide, a beam identification unit will be installed. The details of prototype of the beam diagnostic units and some experiment results will be described in this article

The wastes of nuclear fission

International Nuclear Information System (INIS)

Doubre, H.

2005-01-01

In this paper the author presents the problems of the radioactive wastes generated by the nuclear fission. The first part devoted to the fission phenomenon explains the incident neutron energy and the target nuclei role. The second part devoted to the nuclear wastes sources presents the production of wastes upstream of the reactors, in the reactors and why these wastes are dangerous. The third part discusses the radioactive wastes management in France (classification, laws). The last part details the associated research programs: the radionuclides separation, the disposal, the underground storage, the transmutation and the thorium cycle. (A.L.B.)

1: the atom. 2: radioactivity. 3: man and radiations. 4: the energy. 5: nuclear energy: fusion and fission. 6: the operation of a nuclear reactor. 7: the nuclear fuel cycle

International Nuclear Information System (INIS)

2002-01-01

This series of 7 digest booklets present the bases of the nuclear physics and of the nuclear energy: 1 - the atom (structure of matter, chemical elements and isotopes, the four fundamental interactions, nuclear physics); 2 - radioactivity (definition, origins of radioelements, applications of radioactivity); 3 - man and radiations (radiations diversity, biological effects, radioprotection, examples of radiation applications); 4 - energy (energy states, different forms of energy, characteristics); 5 - nuclear energy: fusion and fission (nuclear energy release, thermonuclear fusion, nuclear fission and chain reaction); 6 - operation of a nuclear reactor (nuclear fission, reactor components, reactor types); 7 - nuclear fuel cycle (nuclear fuel preparation, fuel consumption, reprocessing, wastes management). (J.S.)

TRIUMF-ISAC Gamma-Ray Escape-Suppressed Spectrometer (TIGRESS): a versatile tool for radioactive beam physics

Science.gov (United States)

Ball, G. C.; Andreyev, A.; Austin, R. A. E.; Bandyopadhyay, D.; Becker, J. A.; Boston, A. J.; Boston, H. C.; Chen, A.; Churchman, R.; Cifarelli, F.; Cline, D.; Cooper, R. J.; Cross, D. S.; Dashdorj, D.; Demand, G.; Dimmock, M. R.; Drake, T. E.; Finlay, P.; Gagon-Moisan, F.; Gallant, A. T.; Garrett, P. E.; Green, K. L.; Grint, A. N.; Hackman, G.; Harkness, L. J.; Hayes, A. B.; Kanungo, R.; Leach, K. G.; Lee, G.; Maharaj, R.; Martin, J.-P.; Morton, A. C.; Mythili, S.; Nelson, L.; Newman, O.; Nolan, P. J.; Padilla-Rodal, E.; Pearson, C. J.; Phillips, A. A.; Porter-Peden, M.; Ressler, J. J.; Roy, R.; Ruiz, C.; Savajols, H.; Sarazin, F.; Schumaker, M. A.; Scraggs, D. P.; Svensson, C. E.; Waddington, J. C.; Wan, J. M.; Whitbeck, A.; Williams, S. J.; Wong, J.; Wu, C. Y.

2007-05-01

TIGRESS is a new generation γ-ray spectrometer designed for use with radioactive beams from ISAC. This paper gives an overview of the project and presents results from the first radioactive beam experiment with TIGRESS, the Coulomb excitation of 20,21Na.

Physics and Technology for the Next Generation of Radioactive Ion Beam Facilities: EURISOL

CERN Document Server

Kadi, Y; Catherall, R; Giles, T; Stora, T; Wenander, F K

2012-01-01

Since the discovery of artificial radioactivity in 1935, nuclear scientists have developed tools to study nuclei far from stability. A major breakthrough came in the eighties when the first high energy radioactive beams were produced at Berkeley, leading to the discovery of neutron halos. The field of nuclear structure received a new impetus, and the major accelerator facilities worldwide rivalled in ingenuity to produce more intense, purer and higher resolution rare isotope beams, leading to our much improved knowledge and understanding of the general evolution of nuclear properties throughout the nuclear chart. However, today, further progress is hampered by the weak beam intensities of current installations which correlate with the difficulty to reach the confines of nuclear binding where new phenomena are predicted, and where the r-process path for nuclear synthesis is expected to be located. The advancement of Radioactive Ion Beam (RIB) science calls for the development of so-called next-generation facil...

Research of the Mass Spectra of the Fission Products and Yields of (n, gamma) and (n, 2n) Reactions in a Model Subcritical Uranium Blanket of the Electronuclear System "Energy Plus Transmutation" on Proton Beam of the Dubna Synchrophasotron at 1.5 Ge

CERN Document Server

Chultem, D; Krivopustov, M I; Gerbish, S; Tumendemberel, B; Pavlyuk, A B; Zaveryukha, O S

2002-01-01

This paper is devoted to the research of the spatial distributions of the yields of (n, f), (n, gamma) and (n, 2n) reactions in a two-section model of the uranium blanket electronuclear installation constructed at the Laboratory of High Energies, JINR (Dubna) for experiments according to the program "Research of physical aspects of the electronuclear method of energy production and of radioactive waste transmutation in atomic power-engineering on beams of the synchrophasotron and nuclotron" - project "Energy plus Transmutation". The mass spectrum of the fission products and yields of above reactions in uranium activation detectors placed on the radii of the so-called detector plates is determined. The experimental results testify that the fission of nuclei in the uranium blanket is made by fast neutrons. This conclusion coincides with the result obtained with track integrators of uranium fission.

Production of radioactive molecular beams for CERN-ISOLDE

CERN Document Server

AUTHOR|(SzGeCERN)703149; Kröll, Thorsten

SOLDE, the Isotope Separation On-Line facility, at CERN is a leading facility for the production of beams of exotic radioactive isotopes. Currently over 1000 different isotopes with half lives down to milliseconds can be extracted with beam intensities of up to 10^11 ions per second. However, due to the reactive target environment not all isotopes are extractable in sufficient amounts. In this work the extraction of short lived carbon and boron isotopes is investigated. Therefore a variety of experimental and computanional techniques have been used.

Proceedings of the workshop on prospects for research with radioactive beams from heavy ion accelerators

International Nuclear Information System (INIS)

Nitschke, J.M.

1984-04-01

The SuperHILAC Users Executive Committee organized a workshop on Prospects for Research with Radioactive Beams from Heavy Ion Accelerators. The main purpose of the workshop was to bring together a diverse group of scientists who had already done experients with radioactive beams or were interested in their use in the future. The topics of the talks ranged from general nuclear physics, astrophysics, production of radioactive beams and high energy projectile fragmentation to biomedical applications. This publication contains the abstracts of the talks given at the workshop and copies of the viewgraphs as they were supplied to the editor

Energy from nuclear fission an introduction

CERN Document Server

De Sanctis, Enzo; Ripani, Marco

2016-01-01

This book provides an overview on nuclear physics and energy production from nuclear fission. It serves as a readable and reliable source of information for anyone who wants to have a well-balanced opinion about exploitation of nuclear fission in power plants. The text is divided into two parts; the first covers the basics of nuclear forces and properties of nuclei, nuclear collisions, nuclear stability, radioactivity, and provides a detailed discussion of nuclear fission and relevant topics in its application to energy production. The second part covers the basic technical aspects of nuclear fission reactors, nuclear fuel cycle and resources, safety, safeguards, and radioactive waste management. The book also contains a discussion of the biological effects of nuclear radiation and of radiation protection, and a summary of the ten most relevant nuclear accidents. The book is suitable for undergraduates in physics, nuclear engineering and other science subjects. However, the mathematics is kept at a level that...

Positron emission medical measurements with accelerated radioactive ion beams

International Nuclear Information System (INIS)

Llacer, J.

1988-01-01

This paper reviews in some detail the process by which a heavy ion accelerator can be used to inject positron emitting radioactive particles into a human body for a range of possible medical measurements. The process of radioactive beam generation and injection is described, followed by a study of the relationship between activity that can be injected versus dose to the patient as a function of which of the positron emitting ions is used. It is found that 6 C 10 and 10 Ne 19 are the two isotopes that appear more promising for injection into humans. The design considerations for a non-tomographic instrument to obtain images from beam injections are outlined and the results of 10 Ne 19 preliminary measurements with human phantoms and actual patients for the determination of end-of-range of cancer therapy ion beams is reported. Accuracies in the order of ±1 mm in the measurements of stopping point of a therapy beam with safe doses to the patient are reported. The paper concludes with a simple analysis of requirements to extend the technique to on-line verification of cancer treatment and to nuclear medicine research and diagnostics measurements. 17 refs.; 16 figs.; 3 tabs

Management of radioactive waste from 99Mo production by nuclear fission

International Nuclear Information System (INIS)

Rego, Maria Eugenia de Melo

2013-01-01

Brazil intends to build a facility for the 99 Mo production through 235 U fission, once this radioisotope is largely used in nuclear medicine. This study aimed at estimating the physical, chemical and radiological characteristics of radioactive waste expected to be generated in that facility, and to provide theoretical subsides that can be used on the definition of a proper waste management system. Two production scenarios were established and the radioisotope inventories of the wastes were calculated by Scale®. From the chemical processing of the uranium targets the wastes were characterized on their chemical and radiological features. MicroShield® was used to determine the activity concentrations up to three months of 99 Mo production. In addition, this work presents dose rate calculation for several sizes of shielding and different amount of wastes, collected in a proper package for in-site transportation. Radionuclides responsible for higher doses were identified in order to facilitate choosing the most appropriate method for managing the wastes after their chemical separation and before their storage. These results are part of what is expected on radioactive wastes at a 99 Mo production facility and might help on the development of the waste management planning for that facility. (author)

Organization of customs control of fissionable and other radioactive materials

International Nuclear Information System (INIS)

Ukhlinov, L.; Bojko, V.

2001-01-01

Among the routine inspection tasks of the Sheremetyevo customs office are tasks stemming from international commitments of Russia to prevent proliferation of nuclear weapons and material that can be used for making these weapons. These tasks are: radiation monitoring of all vehicles, passengers, their luggage and goods crossing the state border; inspection of fissionable and radioactive materials (FRM) legally transported by participants in the foreign trade activities with a view to checking that the declared data fully correspond to the actual radioactive cargo. Organizational measures and technical measures at the Sheremetyevo customs office are described in detail. The efficiency of the scheme is illustrated by the following figures. In 1997, when appropriate technical means and trained personnel were lacking, there were only 2 events of detecting items with a rather high radioactivity level in the luggage. In 1999, after the entire radiation monitoring system was fully deployed (i.e. the flight checkpoint was equipped with technical means of radiation monitoring, personnel was trained, special technologies and algorithms were developed), there were 61 events of radiation detection, and in 2000 there have been 90 events, including breaches of legal FRM traffic regulations through disagreement of declared and actual parameters. We believe that the above-considered organization of radiation monitoring allows effective and quite reliable control of and adequate response to possible illicit transport of FRM through the airport Sheremetyevo to other countries, including CIS. In the near future we plan to increase the efficiency of the radiation monitoring by integrating the currently operational customs-used stationary FRM detection systems into a single information network capable of providing simultaneous video-aided continuous nuclear monitoring at three terminals (Sheremetyevo-1, Sheremetyevo-2, Sheremetyevo-Cargo) with display of information at the workstation

Production of radioactive molecular beams for CERN-ISOLDE

Energy Technology Data Exchange (ETDEWEB)

Seiffert, Christoph

2015-06-15

ISOLDE, the Isotope Separation On-Line facility, at CERN is a leading facility for the production of beams of exotic radioactive isotopes. Currently over 1000 different isotopes with half lives down to milliseconds can be extracted with beam intensities of up to 10{sup 11} ions per second. However, due to the reactive target environment not all isotopes are extractable in sufficient amounts. In this work the extraction of short lived carbon and boron isotopes is investigated. Therefore a variety of experimental and computational techniques have been used.

Constraints due to the production of radioactive ion beams in the SPIRAL project

International Nuclear Information System (INIS)

Leroy, R.; Huguet, Y.; Jardin, P.; Marry, C.; Pacquet, J.Y.; Villari, A.C.C.

1997-01-01

The radioactive ion beams that will be delivered by the SPIRAL facility will be produced by the interaction of a stable high energy and high intensity primary ion beam delivered by the GANIL cyclotrons with a carbon target heated to 2000 deg C. During this interaction, some radioactive atoms will be created and will diffuse out of the target before entering into an electron cyclotron resonance ion source where they will be ionized and extracted. The production of radioactive ion beams with this method implies high radiation fields that activate and can damage materials located in the neighborhood of the target. Therefore, the production system which is composed of the permanent magnet ECR ion source coupled to a graphite target will be changed after two weeks of irradiation. As this ensemble will be very radioactive, this operation has to be supervised by remote control. The radiation levels around the target-ion source system and a detailed description of the different precautions that have been taken for safety and for prevention of contamination and irradiation are presented. (author)

Experiments with radioactive nuclear beams II

International Nuclear Information System (INIS)

Aguilera R, E.F.; Martinez Q, E.; Gomez C, A.; Lizcano C, D.; Garcia M, H.; Rosales M, P.

2001-12-01

The studies of nuclear reactions with heavy ions have been carried out for years for the group of heavy ions of the laboratory of the Accelerator of the ININ. Especially in the last years the group has intruded in the studies of nuclear reactions with radioactive beams, frontier theme at world level. Presently Technical Report is presented in detailed form the experimental methods and the analysis procedures of the research activities carried out by the group. The chpater II is dedicated to the procedures used in the analysis of the last two experiments with radioactive beams carried out by the group. In the chapter III is presented the procedure followed to carrying out an extended analysis with the CCDEF code, to consider the transfer channel of nucleons in the description of the fusion excitation functions of a good number of previously measured systems by the group. Finally, in the chapter IV the more important steps to continue in the study of the reaction 12 C + 12 C experiment drifted to be carried out using the available resources of the Tandem Accelerator Laboratory of the ININ are described. At the end of each chapter some of the more representative results obtained in the analysis are presented and emphasis on the scientific production generated by the group for each case is made. (Author)

Removal of some Fission Products from Low Level Liquid Radioactive Waste by Chemical Precipitation liquid/Co-precipitation / Phosphate Coagulant

International Nuclear Information System (INIS)

Borai, E.H.; Attallah, M.F.; Hilal, M.A.; Abo-Aly, M.M.; Shehata, F.A.

2008-01-01

In Egypt radioactive waste has been generated from various uses of radioactive materials. Presence of cesium demonstrated a major problem from the removal point of view even by conventional and advanced technologies. Selective chemical precipitation has been oriented for removal of some fission products including 137 Cs from low level liquid radioactive waste (LLLRW). The aim of the present study was focused to investigate the effectiveness of various phosphate compounds that improved the precipitation process and hence the decontamination factor. The results showed that, maximum removal of 137 Cs reaching 46.4 % using di-sodium hydrogen phosphate as a selective coagulant. It was found that significant enhancement of co-precipitation of 137 Cs (62.5 %) was obtained due to presence of Nd 3+ in the LLLRW

Fission approach to cluster radioactivity

Indian Academy of Sciences (India)

2015-08-04

Aug 4, 2015 ... Also, the analytical superasymmetric fission (ASAF) model is successfully employed to make a systematic search and to predict, with other models, cluster ... those of the staff, the journals, various programmes, and Current Science, has changed from 'ias.ernet.in' (or 'academy.ias.ernet.in') to 'ias.ac.in'. Thus ...

Thorium-uranium fission radiography

Science.gov (United States)

Haines, E. L.; Weiss, J. R.; Burnett, D. S.; Woolum, D. S.

1976-01-01

Results are described for studies designed to develop routine methods for in-situ measurement of the abundance of Th and U on a microscale in heterogeneous samples, especially rocks, using the secondary high-energy neutron flux developed when the 650 MeV proton beam of an accelerator is stopped in a 42 x 42 cm diam Cu cylinder. Irradiations were performed at three different locations in a rabbit tube in the beam stop area, and thick metal foils of Bi, Th, and natural U as well as polished silicate glasses of known U and Th contents were used as targets and were placed in contact with mica which served as a fission track detector. In many cases both bare and Cd-covered detectors were exposed. The exposed mica samples were etched in 48% HF and the fission tracks counted by conventional transmitted light microscopy. Relative fission cross sections are examined, along with absolute Th track production rates, interaction tracks, and a comparison of measured and calculated fission rates. The practicality of fast neutron radiography revealed by experiments to data is discussed primarily for Th/U measurements, and mixtures of other fissionable nuclei are briefly considered.

World new facilities for radioactive isotope beams

International Nuclear Information System (INIS)

Motobayashi, T.

2014-01-01

The use of unstable nuclei in the form of energetic beams for nuclear physics studies is now entering into a new era. 'New-generation' facilities are either in operation, under construction or being planned. They are designed to provide radioactive isotope (RI) beams with very high intensities over a wide range of nuclides. These facilities are expected to provide opportunities to study nuclear structure, astrophysical nuclear processes and nuclear matter with large proton-neutron imbalance in grate detail. This article reports on the current status of such new-generation RI-beam facilities around the world. In order to cover different energy domains and to meet various scientific demands, the designs of RI-beam facilities are of a wide variety. For example, RIBF in Japan, FAIR in Germany and FRIB in US are based on the fragmentation scheme for beams with energies of a few hundred MeV/nucleon to GeV/nucleon, whereas Spiral2 in France, SPES in Italy, HIE-ISOLDE in Switzerland/France, and the future facility EURISOL in Europe are based on the ISOL method, and aim at providing lower-energy RI beams. There are a many other projects including upgrades of existing facilities in the three continents, America, Asia and Europe

Volatilization and reaction of fission products in flowing steam

International Nuclear Information System (INIS)

Johnson, I.; Steidl, D.V.; Johnson, C.E.

1985-01-01

The principal risk to the public from nuclear power plants derives from the highly radioactive atoms (fission products) generated as energy is produced in the nuclear fuel. The revolatilization of fission products from reactor system surfaces due to self-heating by radioactive decay has become a complicating factor in the source-term redefinition effort. It has had a major impact on calculations of fission product distributions in accident safety analyses. The focus of this research effort was to investigate the volatilization and transport of fission products and control rod materials in a flowing gaseous steam-hydrogen mixture. Fission product and control rod materials in various combinations were studied including CsI, CsOH, TeO 2 , SrO, Ag, In, Cd and Mn. The vaporization behavior of the deposits were characterized with respect to vaporization rates, chemical species and downstream transport behavior

EURISOL-DS Multi-MW Target: Thermal Behaviour of the fission target disk arrangement inspired by the MAFF project

CERN Document Server

Cyril Kharoua, Yacine Kadi and the EURISOL-DS Task#2 collaboration

This technical note summarises the design calculations performed within Task #2 of the European Isotope Separation On-Line Radioactive Ion Beam Facility Design Study (EURISOL-DS) [1] for the thermal behaviour of the fission target.A preliminary study was carried out in order to determine the heat deposition within the fissile material and estimate the temperature rise. This new solution takes into account the problems related to effusion/diffusion of radioactive isotopes inside a thick target. To enhance the extraction rates and the thermal behaviour it is proposed to study a solution where the fissile material is split into an arrangement of disks.

Ternary fission

Indian Academy of Sciences (India)

the energy minimization of all possible ternary breakups of a heavy radioactive nucleus. Further, within the TCM we have analysed the competition between different geometries as well as different positioning of the fragments. Also, an attempt was made to calculate the mass distribution of ternary fission process within the ...

Ion sources development at GANIL for radioactive beams and high charge state ions

International Nuclear Information System (INIS)

Leroy, R.; Barue, C.; Canet, C.; Dupuis, M.; Flambard, J.L.; Gaubert, G.; Gibouin, S.; Huguet, Y.; Jardin, P.; Lecesne, N.; Leherissier, P.; Lemagnen, F.; Pacquet, J.Y.; Pellemoine-Landre, F.; Rataud, J.P.; Saint-Laurent, M.G.; Villari, A.C.C.; Maunoury, L.

2001-01-01

The GANIL laboratory has in charge the production of ion beams for nuclear and non nuclear physics. This article reviews the last developments that are underway in the fields of radioactive ion beam production, increase of the metallic ion intensities and production of highly charges ion beams. (authors)

Radioactivity. Centenary of radioactivity discovery

International Nuclear Information System (INIS)

Charpak, G.; Tubiana, M.; Bimbot, R.

1997-01-01

This small booklet was edited for the occasion of the exhibitions of the celebration of the centenary of radioactivity discovery which took place in various locations in France from 1996 to 1998. It recalls some basic knowledge concerning radioactivity and its applications: history of discovery, atoms and isotopes, radiations, measurement of ionizing radiations, natural and artificial radioactivity, isotope dating and labelling, radiotherapy, nuclear power and reactors, fission and fusion, nuclear wastes, dosimetry, effects and radioprotection. (J.S.)

Combined in-beam gamma-ray and conversion electron spectroscopy with radioactive ion beams

Directory of Open Access Journals (Sweden)

Konki J.

2013-12-01

Full Text Available In-beam gamma-ray and electron spectroscopy have been widely used as tools to study the broad variety of phenomena in nuclear structure. The SPEDE spectrometer is a new device to be used in conjunction with the MINIBALL germanium detector array to enable the detection of internal conversion electrons in coincidence with gamma rays from de-exciting nuclei in radioactive ion beam experiments at the upcoming HIE-ISOLDE facility at CERN, Switzerland. Geant4 simulations were carried out in order to optimise the design and segmentation of the silicon detector to achieve good energy resolution and performance.

Radioactive aerosols

International Nuclear Information System (INIS)

Chamberlain, A.C.

1991-01-01

Radon. Fission product aerosols. Radioiodine. Tritium. Plutonium. Mass transfer of radioactive vapours and aerosols. Studies with radioactive particles and human subjects. Index. This paper explores the environmental and health aspects of radioactive aerosols. Covers radioactive nuclides of potential concern to public health and applications to the study of boundary layer transport. Contains bibliographic references. Suitable for environmental chemistry collections in academic and research libraries

Synthesis and investigation of superheavy elements - perspectives with radioactive beams

International Nuclear Information System (INIS)

Muenzenberg, G.

1997-09-01

The perspectives for the investigation of heavy and superheavy elements with intense beams of radioactive nuclei available from the new generation of secondary beam facilities in combination with modern experimental developments are the subject of this paper. The nuclear properties of the recently discovered shell nuclei centered at Z=108 and N=164 and predictions on the location of the superheavy region with improved theoretical models will be discussed. (orig.)

The discovery of uranium fission

International Nuclear Information System (INIS)

Brix, P.

1990-01-01

Uranium was discovered 200 years ago. Its radioactive character was first demonstrated in 1896 and two years later radium was extracted from uranium minerals. In 1911 studies with alpha rays from radioactive decay led to the unexpected discovery of the atomic nucleus. Exposure of beryllium to alpha rays yielded neutrons, first detected in 1932. Starting in 1934, neutron irradiation of uranium produced radioactive substances erroneously attributed to transuranium elements but with confusing properties. Painstaking experiments by chemists left no doubt on 17 December 1938 that barium was produced by these irradiations: the neutrons had split some uranium nuclei. The physics of the fission process was understood two weeks later; after a few months, neutron multiplication was found to be probable. This review deals with the eminent scientists involved, their successes, errors and disappointments, and the unexpected insights which occurred on the paths and detours of scientific research. It is, therefore, instructive also to discuss how fission was not discovered. The momentous discovery must be considered inevitable; the great tragedy was that Germany started World War II just at the time when the possibility of nuclear chain reactions and bombs became known. The consequences and anxieties that remain after 50 years of nuclear fission demand that mankind act with reason and conscience to maintain peace. (author)

Proposal of measuring the mechanisms of nuclear excitation leading to fission with the ADONE jet-target tagged photon beam

International Nuclear Information System (INIS)

Lucherini, V.; Bianchi, N.; De Sanctis, E.; Guaraldo, C.; Levi Sandri, P.; Muccifora, V.; Polli, E.; Reolon, A.R.; Aiello, S.; De Filippo, E.; Lanzano', G.; Lo Nigro, S.; Milone, C.; Pagano, A.; Botvina, A.S.; Iljinov, A.S.; Mebel, M.V.

1990-01-01

The mechanisms of excitation with subsequent fission of heavy nuclei can be conveniently studied by means of photons, since this probe is able to interact deeply inside the nucleus. We propose the use of the (200-1200 MeV) tagged photon beam from the ADONE Jet Target in order to study the mass-energy and total momentum distributions of fission fragments, to obtain experimental information on the configurations (excitation energy and nucleonic composition) of produced compound nuclei and on their decay channels

Development of windowless liquid lithium targets for fragmentation and fission of 400-kW uranium beams

CERN Document Server

Nolen, J A; Hassanein, A; Novick, V J; Plotkin, P; Specht, J R

2003-01-01

The driver linac of the proposed rare isotope accelerator facility is designed to deliver 2x10 sup 1 sup 3 uranium ions per second at 400 MeV/u on target for radionuclide production via the fission and fragmentation mechanisms. The ion optics of the large acceptance, high-resolution fragment separators that follow the production target require primary beam spot widths of 1 mm. To cope with the resulting high power densities, windowless liquid lithium targets are being developed. The present designs build on existing experience with liquid lithium and liquid sodium systems that have been used for fusion and fission applications. However, no completely windowless systems have been developed or tested to date. For the beam power indicated above (400 kW), the flow requirements are up to about 20 m/s and 10 l/s linear and volume flow rates, respectively. The required target thickness is 1-1.5 g/cm sup 2 (2-3 cm lithium thickness). At this time a prototype windowless system with a lithium thickness of 1-2 cm is und...

Muon catalyzed fusion - fission reactor driven by a recirculating beam

International Nuclear Information System (INIS)

Eliezer, S.; Tajima, T.; Rosenbluth, M.N.

1986-01-01

The recent experimentally inferred value of multiplicity of fusion of deuterium and tritium catalyzed by muons has rekindled interest in its application to reactors. Since the main energy expended is in pion (and consequent muon) productions, we try to minimize the pion loss by magnetically confining pions where they are created. Although it appears at this moment not possible to achieve energy gain by pure fusion, it is possible to gain energy by combining catalyzed fusion with fission blankets. We present two new ideas that improve the muon fusion reactor concept. The first idea is to combine the target, the converter of pions into muons, and the synthesizer into one (the synergetic concept). This is accomplished by injecting a tritium or deuterium beam of 1 GeV/nucleon into DT fuel contained in a magnetic mirror. The confined pions slow down and decay into muons, which are confined in the fuel causing little muon loss. The necessary quantity of tritium to keep the reactor viable has been derived. The second idea is that the beam passing through the target is collected for reuse and recirculated, while the strongly interacted portion of the beam is directed to electronuclear blankets. The present concepts are based on known technologies and on known physical processes and data. 29 refs., 6 figs., 4 tabs

γ-spectroscopy and radioactive beams: search for highly deformed exotic nuclei

International Nuclear Information System (INIS)

Rosse, B.

2006-07-01

This work is devoted to the search for highly deformed nuclei under extreme conditions of isospin, located near the proton drip-line, around A ∼ 130. The experiment was performed at GANIL (Caen) with the SPIRAL radioactive beam facility. The nuclei of interest were produced by fusion-evaporation reactions induced by the neutron deficient Kr 76 radioactive beam (T1/2 = 14.8 h). γ-rays were detected by the EXOGAM array, composed of 11 segmented germanium clover detectors, for which a new segment calibration method has been developed. To extract fusion-evaporation events of a overwhelming background due to the radioactivity of the beam, the EXOGAM array was coupled with the light charged particle detector DIAMANT and the high acceptance VAMOS spectrometer. The latter was used for the first time to detect fusion-evaporation residues. The detailed data analysis allowed us to demonstrate that the EXOGAM + DIAMANT + VAMOS coupling is operational and essential to investigate the structure of these nuclei. Furthermore, the first γ transition was observed in the very exotic odd-odd Pm 130 nucleus. The results have been interpreted with static and dynamic self-consistent microscopic calculations in collaboration with the Theoretical Physicists of the IPN Lyon. (author)

γ-spectroscopy and radioactive beams: search for highly deformed exotic nuclei

International Nuclear Information System (INIS)

Rosse, Bertrand

2006-01-01

This work is devoted to the search for highly deformed nuclei under extreme conditions of isospin, located near the proton drip-line, around A∼130. The experiment was performed at GANIL (Caen) with the SPIRAL radioactive beam facility. The nuclei of interest were produced by fusion-evaporation reactions induced by the neutron deficient 76 Kr radioactive beam (T 1/2 = 14.8 h). γ-rays were detected by the EXOGAM array, composed of 11 segmented germanium clover detectors, for which a new segment calibration method has been developed. To extract fusion-evaporation events of a overwhelming background due to the radioactivity of the beam, the EXOGAM array was coupled with the light charged particle detector DIAMANT and the high acceptance VAMOS spectrometer. The latter was used for the first time to detect fusion-evaporation residues. The detailed data analysis allowed us to demonstrate that the EXOGAM + DIAMANT + VAMOS coupling is operational and essential to investigate the structure of these nuclei. Furthermore, the first γ transition was observed in the very exotic odd-odd 130 Pm nucleus. The results have been interpreted with static and dynamic self-consistent microscopic calculations in collaboration with the Theoretical Physicists of the IPN Lyon. (author)

Measurement of residual radioactivity in cooper exposed to high energy heavy ion beam

Energy Technology Data Exchange (ETDEWEB)

Kim, Eunjoo; Nakamura, Takashi [Tohoku Univ., Sendai (Japan). Cyclotron and Radioisotope Center; Uwamino, Yoshitomo; Ito, Sachiko; Fukumura, Akifumi

1999-03-01

The residual radioactivities produced by high energy heavy ions have been measured using the heavy ion beams of the Heavy Ion Medical Accelerator (HIMAC) at National Institute of Radiological Sciences. The spatial distribution of residual radioactivities in 3.5 cm, 5.5 cm and 10 cm thick copper targets of 10 cm x 10 cm size bombarded by 290 MeV/u, 400 MeV/u-{sup 12}C ion beams and 400 MeV/u-{sup 20}Ne ion beam, respectively, were obtained by measuring the gamma-ray activities of 0.5 mm thick copper foil inserted in the target with a high purity Ge detector after about 1 hour to 6 hours irradiation. (author)

Contamination of the air and other environmental samples of the Ulm region by radioactive fission products after the accident of the Chernobyl reactor

International Nuclear Information System (INIS)

Krivan, V.; Egger, K.P.; Hausbeck, R.; Schmid, W.

1986-01-01

Since April 30, 1986, the radioactivity of the fission products released by the accident of the Chernobyl reactor has been measured in the air of the city of Ulm. The airborne dust samples were collected with flow calibrated samplers on cellulose acetate membrane filters and counted with a high resolution gamma ray spectrometer. Later on, the radioactivity measurements were expanded to other relevant environmental samples contaminated by radioactive atmospheric precipitates including grass, spruce needles, mosses, lichens, various kinds of food, drinking water, asphalt and concrete surface layers, municipal sewage sludge and sewage sludge ash. This paper reports the obtained results. (orig.) [de

Regulatory aspects of fusion power-lessons from fission plants

International Nuclear Information System (INIS)

Natalizio, A.; Brunnader, H.; Sood, S.K.

1993-01-01

Experience from fission reactors has shown the regulatory process for licensing a nuclear facility to be legalistic, lengthy, unpredictable, and costly. This experience also indicates that much of the regulatory debate is focused on safety margins, that is, the smaller the safety margins the bigger the regulatory debate and the greater the amount of proof required to satisfy the regulatory. Such experience suggests that caution and prudence guide the development of a regulatory regime for fusion reactors. Fusion has intrinsic safety and environmental advantages over fission, which should alleviate significantly, or even eliminate, the regulatory problems associated with fission. The absence of a criticality concern and the absence of fission products preclude a Chernobyl type accident from occurring in a fusion reactor. Although in a fusion reactor there are large inventories of radioactive products that can be mobilized, the total quantity is orders of magnitude smaller than in fission power reactors. The bulk of the radioactivity in a fusion reactor is either activation products in steel structures, or tritium fuel supplies safely stored in the form of a metal tritide in storage beds. The quantity of tritium that can be mobilized under accident conditions is much less than ten million curies. This compares very favorably with a fission product inventory greater than ten billion curies in a fission power reactor. Furthermore, in a fission reactor, all of the reactivity is contained in a steel vessel that is pressurized to about 150 atmospheres, whereas in a fusion reactor, the inventory of radioactive material is dispersed in different areas of the plant, such that it is improbable that a single event could give rise to the release of the entire inventory to the environment. With such significant intrinsic safety advantages there is no a priori need to make fusion requirements/regulations more demanding and more stringent than fission

Selection and design of ion sources for use at the Holifield radioactive ion beam facility

International Nuclear Information System (INIS)

Alton, G.D.; Haynes, D.L.; Mills, G.D.; Olsen, D.K.

1994-01-01

The Holifield Radioactive Ion Beam Facility now under construction at the Oak Ridge National Laboratory will use the 25 MV tandem accelerator for the acceleration of radioactive ion beams to energies appropriate for research in nuclear physics; negative ion beams are, therefore, required for injection into the tandem accelerator. Because charge exchange is an efficient means for converting initially positive ion beams to negative ion beams, both positive and negative ion sources are viable options for use at the facility. The choice of the type of ion source will depend on the overall efficiency for generating the radioactive species of interest. Although direct-extraction negative ion sources are clearly desirable, the ion formation efficiencies are often too low for practical consideration; for this situation, positive ion sources, in combination with charge exchange, are the logical choice. The high-temperature version of the CERN-ISOLDE positive ion source has been selected and a modified version of the source designed and fabricated for initial use at the facility because of its low emittance, relatively high ionization efficiencies, and species versatility, and because it has been engineered for remote installation, removal, and servicing as required for safe handling in a high-radiation-level ISOL facility. The source will be primarily used to generate ion beams from elements with intermediate to low electron affinities. Prototype plasma-sputter negative ion sources and negative surface-ionization sources are under design consideration for generating radioactive ion beams from high-electron-affinity elements. The design features of these sources and expected efficiencies and beam qualities (emittances) will be described in this report

Gamma spectroscopy: from steady beams to radioactive beams

International Nuclear Information System (INIS)

Stezowski, O.

2008-06-01

The author gives an overview of his research works in the field of gamma spectroscopy. First, he recalls some results of experiments performed for the study of peculiar structures associated with different modes of nucleus rotation, and notably in the case of collective rotation of deformed and even super-deformed nuclei. Then, he details tools and methods used to experimentally determine the level scheme. The main characteristics of steady and radioactive beams are briefly presented, and their complementarities and differences are highlighted. Specific spectrometers and sensors are described. In a last chapter, the author discusses several research projects he is involved in, and more particularly the 'gamma tracking' which is the fundamental principle for gamma multi-sensors of the next generations

Neutron-rich rare isotope production from projectile fission of heavy beams in the energy range of 20 MeV/nucleon

OpenAIRE

Vonta, N.; Souliotis, G. A.; Loveland, W. D.; Kwon, Y. K.; Tshoo, K.; Jeong, S. C.; Veselsky, M.; Bonasera, A.; Botvina, A.

2016-01-01

We investigate the possibilities of producing neutron-rich nuclides in projectile fission of heavy beams in the energy range of 20 MeV/nucleon expected from low-energy facilities. We report our efforts to theoretically describe the reaction mechanism of projectile fission following a multinucleon transfer collision at this energy range. Our calculations are mainly based on a two-step approach: the dynamical stage of the collision is described with either the phenomenological Deep-Inelastic Tr...

The experience of Russian Federation in organization of customs control of fissionable and other radioactive materials

International Nuclear Information System (INIS)

Podchishaev, A.

2001-01-01

Among the routine inspection tasks of customs offices are tasks stemming from international commitments of Russia to prevent proliferation of nuclear weapons and material that can be used for making these weapons. These tasks are: radiation monitoring of all vehicles, passengers, their luggage and goods crossing the state border; inspection of fissionable and radioactive materials (FRM) legally transported by participants in the foreign trade activities with a view to checking that the declared data fully correspond to the actual radioactive cargo. Organizational measures involve the Sheremetyevo customs office has a department whose personnel is specially trained in radiation monitoring and can operate radiometric and spectrometric instruments. These specialists are included in shifts on duty responsible for customs clearing and inspection and carry out continuous radiation monitoring of passengers and their luggage, vehicles and goods crossing the border. They work on the 24-hour basis, which allows quickly and skillfully localizing the detected radiation source and avoiding direct contact of customs, officers, airport personnel, and passengers with the radioactive item. Technical measures include provision and everyday use of radiation monitoring instrumentation, classified as: stationary equipment of primary radiation monitoring (SEPRM); hand-held instruments for additional radiation monitoring (RM); spectrometric equipment for control of legal FRM transport. The customs procedure for monitoring of fissionable and radioactive materials is divided into three stages. Stage I, primary RM is carried out by stationary FRM detection systems Yantar for customs applications installed on the customs inspection line next to the X-ray inspection equipment (XIE). Stage II, additional RM is carried out by officer who uses hand-held instruments to check the passenger's luggage for surface contamination; to perform primary identification of the detected radioactive source

Transport of radioactive ion beams and related safety issues: The {sup 132}Sn{sup +} case study

Energy Technology Data Exchange (ETDEWEB)

Osswald, F., E-mail: francis.osswald@iphc.cnrs.fr; Bouquerel, E.; Boutin, D.; Dinkov, A.; Sellam, A. [IPHC/IN2P3/CNRS, University of Strasbourg, 67037 Strasbourg (France); Kazarinov, N. [JINR/FLNR, 141980 Dubna (Russian Federation); Perrot, L. [IPNO/IN2P3/CNRS, University of Paris-Sud-11, 91406 Orsay (France)

2014-12-15

The transport of intense radioactive ion beam currents requires a careful design in order to limit the beam losses, the contamination and thus the dose rates. Some investigations based on numerical models and calculations have been performed in the framework of the SPIRAL 2 project to evaluate the performance of a low energy beam transport line located between the isotope separation on line (ISOL) production cell and the experiment areas. The paper presents the results of the transverse phase-space analysis, the beam losses assessment, the resulting contamination, and radioactivity levels. They show that reasonable beam transmission, emittance growth, and dose rates can be achieved considering the current standards.

Investigating proton emitters at the limits of stability with radioactive beams from the Oak Ridge facility

Energy Technology Data Exchange (ETDEWEB)

Toth, K.S. [Oak Ridge National Lab., TN (United States); Batchelder, J.C.; Zganjar, E.F. [Louisiana State Univ., Baton Rouge, LA (United States); Bingham, C.R.; Wauters, J. [Tennessee Univ., Knoxville, TN (United States); Davinson, T.; MacKenzie, J.A.; Woods, P.J. [Edinburgh Univ. (United Kingdom)

1996-10-01

By using beams from the Holifield Radioactive Ion Beam Facility at ORNL, it should be possible to identify many new ground-state proton emitters in the mass region from Sn to Pb. In these investigations nuclei produced in fusion-evaporation reactions will be separated from incident ions and dispersed in mass/charge with a recoil mass separator and then implanted into a double-sided Si strip detector for study of proton (and {alpha}-particle) radioactivity. This paper summarizes data presently extant on proton emitters and then focuses on tests and initial experiments that will be carried out with stable beams and with radioactive ions as they are developed at the Oak Ridge facility.

Radioactive and Other Effects of Nuclear Explosion

International Nuclear Information System (INIS)

Ilijas, B.; Cizmek, A.; Prah, M.; Medakovic, S.

2008-01-01

As a result of long lasting efforts of international community to definitely ban all test nuclear explosions, the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was opened for signature in New York on 24 September 1996, when it was signed by 71 states, including Croatia. The State Office for Nuclear Safety (SONS) which, as an independent state regulatory authority has a responsibility for activities relating to nuclear safety, including the national authority over this Treaty, is actively engaged in CTBTO activities. The nuclear explosion causes a lot of effects (blast, thermal, radioactive, electromagnetic) which differs a lot in its nature, reach, lasting and other. The longest lasting aftermath is from the radioactive effects that cause a radioactive fallout and a lot of radioactive elements in the environment, created by the influence of a primary beam of radiation. Fission and fusion are the main source of radionuclide created by the nuclear explosion, and the longest lasting aftermaths are by the fission products, namely their offspring in natural disintegration chains. This can make contaminated areas inappropriate for life for very long periods. Even in the case of underground nuclear explosion (when underground cavity is formed with no effects on the surface), a leakage of radioactive gases through cracks is possible. A number of radionuclide is created by the neutron activation of elements naturally present in an environment, because a very strong neutron radiation appears in the moment of nuclear explosion. The abundance of particular radionuclide is a very much dependent of a place of performing nuclear explosion and a composition of soil or water in the vicinity.(author)

Fission of nuclei far from stability

International Nuclear Information System (INIS)

Schmidt, K.H.; Benlliure, J.; Junghans, A.R.

2000-11-01

The secondary-beam facility of GSI provided the technical equipment for a new kind of fission experiment. Fission properties of short-lived neutron-deficient nuclei have been investigated in inverse kinematics. The measured element distributions reveal new kinds of systematics on shell structure and even-odd effects and lead to an improved understanding of structure effects in nuclear fission. Prospects for further experimental studies are discussed. (orig.)

Study of fission reactions induced by 4,6He and 7Li beams on 209Bi and 208Pb targets

Directory of Open Access Journals (Sweden)

Lukyanov S.M.

2013-12-01

Full Text Available Study of fission reactions induced by 4,6He and 7Li beams on 209Bi and 208Pb targets, leading to the production of 210,212A compound nuclei, was performed. It was shown that the fission excitation functions for the three reactions 4,6He + 209Bi and 7Li + 208Pb had similar behavior within the experimental error for a broad range of energy. More likely, halo structure of 6He is not reflected on the fission reaction mechanism. Otherwise, a large value of the fusion cross section was observed so far, as it could be expected in the case of weakly bound character of 6He projectile.

Ternary fission

International Nuclear Information System (INIS)

Wagemans, C.

1991-01-01

Since its discovery in 1946, light (charged) particle accompanied fission (ternary fission) has been extensively studied, for spontaneous as well as for induced fission reactions. The reason for this interest was twofold: the ternary particles being emitted in space and time close to the scission point were expected to supply information on the scission point configuration and the ternary fission process was an important source of helium, tritium, and hydrogen production in nuclear reactors, for which data were requested by the nuclear industry. Significant experimental progress has been realized with the advent of high-resolution detectors, powerful multiparameter data acquisition systems, and intense neutron and photon beams. As far as theory is concerned, the trajectory calculations (in which scission point parameters are deduced from the experimental observations) have been very much improved. An attempt was made to explain ternary particle emission in terms of a Plateau-Rayleigh hydrodynamical instability of a relatively long cylindrical neck or cylindrical nucleus. New results have also been obtained on the so-called open-quotes trueclose quotes ternary fission (fission in three about-equal fragments). The spontaneous emission of charged particles has also clearly been demonstrated in recent years. This chapter discusses the main characteristics of ternary fission, theoretical models, light particle emission probabilities, the dependence of the emission probabilities on experimental variables, light particle energy distributions, light particle angular distributions, correlations between light particle accompanied fission observables, open-quotes trueclose quotes ternary fission, and spontaneous emission of heavy ions. 143 refs., 18 figs., 8 tabs

A brief history of the ''Delayed'' discovery of nuclear fission

International Nuclear Information System (INIS)

Holden, N.E.

1989-08-01

This year marks the Fiftieth Anniversary of the discovery of Nuclear Fission. In the early 1930's, the neutron was discovered, followed by the discovery of artificial radioactivity and then the use of the neutron to produce artificial radioactivity. The first experiments resulting in the fission of uranium took place in 1934. A paper which speculated on fission as an explanation was almost immediately published, yet no one took it seriously not even the author herself. Why did it take an additional five years before anyone realized what had occurred? This is an abnormally long time in a period when discoveries, particularly in nuclear physics, seemed to be almost a daily occurrence. The events which led up to the discovery are recounted, with an attempt made to put them into their historical perspective. The role played by Mendeleev's Periodic Table, the role of the natural radioactive decay chain of uranium, the discovery of protactinium, the apparent discovery of masurium (technetium) and a speculation on the reason why Irene Curie may have missed the discovery of nuclear fission will all be discussed. 43 refs

Low (50 keV) and medium (∼10 MeV) energy radioactive beams at Louvain-la-Neuve

International Nuclear Information System (INIS)

Huyse, M.; Decrock, P.; Dendooven, P.; Reusen, G.; Duppen, P. Van; Wauters, J.

1991-01-01

Low energy radioactive beams are produced at the Leuven Isotope Separator On Line (LISOL) facility in Louvain-la-Neuve. The beams are used for standard nuclear spectroscopy studies and for nuclear orientation on line measurements. Since September 1987 a new project has been started up to accelerate radioactive beams to energies in the range of astrophysical interest. A beam of 10 6 13 N ions per seconde with an energy of 8.5 MeV has been produced last June. (author) 11 refs.; 1 fig.; 1 tab

High spin studies with radioactive ion beams

International Nuclear Information System (INIS)

Garrett, J.D.

1992-01-01

The variety of new research possibilities afforded by the culmination of the two frontier areas of nuclear structure: high spin and studies far from nuclear stability (utilizing intense radioactive ion beams) are discussed. Topics presented include: new regions of exotic nuclear shape (e.g. superdeformation, hyperdeformation, and reflection-asymmetric shapes); the population of and consequences of populating exotic nuclear configurations; and complete spectroscopy (i.e. the overlap of state of the art low-and high-spin studies in the same nucleus)

Understanding radioactive waste

International Nuclear Information System (INIS)

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)

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)

Progress in fission product nuclear data. No. 14

International Nuclear Information System (INIS)

Lammer, M.

1994-06-01

This is the 14th issue of a report series on Fission Product Nuclear Data published by the Nuclear Data Section of the IAEA. The types of activities included are measurements, compilations and evaluations of fission product yields, neutron reaction cross sections of fission products, data related to the radioactive decay of fission products, delayed neutron data from neutron induced and spontaneous fission, lumped fission product data. The first part of the report consists of unaltered original contributions which the authors have sent to IAEA/NDS. The second part contains some recent references relative to fission product nuclear data, which were not covered by the contributions submitted, and selected papers from conferences. The third part contains requirements for further measurements

Progress in fission product nuclear data. No. 13

International Nuclear Information System (INIS)

Lammer, M.

1990-11-01

This is the 13th issue of a report series published by the Nuclear Data Section of the IAEA. The types of activities included are measurements, compilations and evaluations of: Fission product yields (neutron induced and spontaneous fission), neutron reaction cross-sections of fission products, data related to the radioactive decay of fission products, delayed neutron data of fission products and bumped fission product data (decay heat, absorption, etc.). The first part of the report consists of unaltered original data which the authors have sent to IAEA/NDS. The second part contains some recent references relative to fission product nuclear data, which were not covered by the contributions submitted, and selected papers from conferences. Part 3 contains requirements for further measurements

Radioactive ion beam production challenges at the Holifield Heavy Ion Research Facility

International Nuclear Information System (INIS)

Meigs, M.J.; Alton, G.D.; Dowling, D.T.; Haynes, D.L.; Jones, C.M.; Juras, R.C.; Lane, S.N.; Mills, G.D.; Mosko, S.W.; Olsen, D.K.; Tatum, B.A.

1992-01-01

The radioactive ion beam (RIB) project at the Holifield Heavy Ion Research Facility (HHIRF) will provide for reconfiguration of the HHIRF accelerator system to enable provision of low-intensity RIBs for nuclear and astrophysics research. As we have progressed with the design of the reconfiguration, we have encountered several challenges that were not immediately obvious when first contemplating the project. The challenges do not seem insurmountable but should keep life interesting for those of us doing the work. A brief review of the project will allow a better understanding of the challenges in RIB production. Radioactive ion beams will be produced with the Isotope Separator On-Line (ISOL) postacceleration technique. In particular, radioactive atoms will be produced by reactions in the thick stopping target of an ISOL-type target-ion source assembly using intense beams from the Oak Ridge Isochronous Cyclotron equipped with a light-ion internal source. This ISOL target-ion source assembly will be mounted on a high-voltage platform with a mass separator. The target ion source will operate at potentials up to 50 kV with respect to the high voltage platform. The radioactive atoms produced by nuclear reactions in the target diffuse to the surface of the heated target material, desorb from this surface, and effuse through a heated transfer tube into an ion source where ionization and extraction take place. Two types of ion sources will be initially considered. A Forced Electron Beam Induced Arc Discharge source, similar to those used by the ISOLDE facility at CERN and by the UNISOR facility at ORNL, will be built to produce positive ions. These positive ions will be focused through an alkali vapor charge-exchange canal to produce negative ions for tandem injection. In addition, a direct negative surface ionization addition or modification to the above source will be built and investigated

Studies of nuclei using radioactive beams

International Nuclear Information System (INIS)

Piercey, R.B.

1989-07-01

The 12 month period from May 1988 to July 1989 represents the first full year of our 18 month pilot program in nuclear structure research. In this period, research was initiated to develop a capability for radioactive secondary beams at Argonne National Laboratory using the Atlas and the new Fragment Mass Analyzer (FMA), which is currently under construction. Two major new detector facilities are currently in the final stages of design and testing. The Large-Area, Scintillator Telescope (LAST) detector is fully operational and will be shipped to Argonne National Laboratory in August for fit-tests and in-beam calibrations. The first segments of a new sixteen-segment neutron multiplicity detector have been built and tested. The remaining segments are currently being constructed. Research was continued in the areas of (1) Coulomb excitation studies of rare earth and actinide nuclei; (2) In-beam, gamma-ray spectroscopy of nuclei in the mass 100 region, and (3) Advanced detector design. Several journal articles and abstracts were published or submitted for publication in the reporting period, and others are currently in preparation. Three graduate students participated in the program, one from the University of Florida and two from the Royal Institute of Technology, Stockholm, Sweden

RIKEN radioactive isotope beam factory project – Present status and ...

Indian Academy of Sciences (India)

Programs for studying nuclear reactions and structure of exotic nuclei available at the RIKEN radioactive isotope beam factory project are introduced and discussed by demonstrating recent highlights. Special emphasis ... RIKEN Nishina Center for Accelerator-Based Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan ...

Progress in fission product nuclear data

International Nuclear Information System (INIS)

Lammer, M.

1981-06-01

This is the seventh issue of a report series on Fission Product Nuclear Data (FPND) which is published by the Nuclear Data Section (NDS) of the International Atomic Energy Agency (IAEA). The purpose of this series is to inform scientists working on FPND, or using such data, about all activities in this field which are planned, ongoing, or have recently been completed. The present issue contains also a section with some recent references relative to fission product nuclear data, which were not covered by the contributions submitted. The types of activities being included in this report are measurements, compilations and evaluations of: fission product yields (neutron induced and spontaneous fission); neutron reaction cross sections of fission products; data related to the radioactive decay of fission products; delayed neutron data of fission products; and lumped fission product data (decay heat, absorption etc.). The sixth issue of this series has been published in June 1980 as INDC(NDS)-113/G+P. The present issue includes contributions which were received by NDS between 1 August 1980 and 25 May 1981

A combined thermal dissociation and electron impact ionization source for radioactive ion beam generationa

International Nuclear Information System (INIS)

Alton, G.D.; Williams, C.

1996-01-01

The probability for simultaneously dissociating and efficiently ionizing the individual atomic constituents of molecular feed materials with conventional, hot-cathode, electron-impact ion sources is low and consequently, the ion beams from these sources often appear as mixtures of several molecular sideband beams. This fragmentation process leads to dilution of the intensity of the species of interest for radioactive ion beam (RIB) applications where beam intensity is at a premium. We have conceived an ion source that combines the excellent molecular dissociation properties of a thermal dissociator and the high ionization efficiency characteristics of an electron impact ionization source that will, in principle, overcome this handicap. The source concept will be evaluated as a potential candidate for use for RIB generation at the Holifield Radioactive Ion Beam Facility, now under construction at the Oak Ridge National Laboratory. The design features and principles of operation of the source are described in this article. copyright 1996 American Institute of Physics

Nuclear Structure Studies On Exotic Nuclei With Radioactive Beams - Present Status And Future Perspectives At FAIR

International Nuclear Information System (INIS)

Peter Egelhof

2011-01-01

The investigation of nuclear reactions using radioactive beams in inverse kinematics gives access to a wide field of nuclear structure studies in the region far off stability. The basic concept and the methods involved are briefly discussed, and an overview including some selected examples of recent results obtained with radioactive beams from the present fragment separator at GSI Darmstadt is presented. The experimental conditions expected at the future international facility FAIR will, among others, allow for a substantial improvement in intensity and quality of radioactive beams as compared to present facilities. Therefore, it is expected that FAIR will provide unique opportunities for nuclear structure studies on nuclei far off stability, and will allow to explore new regions in the chart of nuclides of high interest for nuclear structure and nuclear astrophysics. A brief overview on the new facility, and on the experimental setups planned for nuclear structure research with radioactive beams is given. For nuclear reaction studies several complex, highly efficient, high resolution, and universal detection systems such as R 3 B, EXL, ELISe, etc. are presently under design and construction. A brief overview on the research objectives and the technical realization will be presented. (author)

High spin studies with radioactive ion beams

Energy Technology Data Exchange (ETDEWEB)

Garrett, J D [Oak Ridge National Lab., TN (United States)

1992-08-01

The variety of new research possibilities afforded by the culmination of the two frontier areas of nuclear structure: high spin and studies far from nuclear stability (utilizing intense radioactive ion beams) are discussed. Topics presented include: new regions of exotic nuclear shape (e.g. superdeformation, hyperdeformation, and reflection-asymmetric shapes); the population of and consequences of populating exotic nuclear configurations; and, complete spectroscopy (i.e. the overlap of state of the art low- and high-spin studies in the same nucleus). (author). 47 refs., 8 figs.

Fission product detection

International Nuclear Information System (INIS)

Liatard, E.; Akrouf, S.; Bruandet, J.F

1987-01-01

The response of photovoltaic cells to heavy ions and fission products have been tested on beam. Their main advantages are their extremely low price, their low sensitivity to energetic light ions with respect to fission products, and the possibility to cut and fit them together to any shape without dead zone. The time output signals of a charge sensitive preamplifier connected to these cells allows fast coincidences. A resolution of 12ns (F.W.H.M.) have been measured between two cells [fr

Focus on radioactivity

Energy Technology Data Exchange (ETDEWEB)

Lambert, M

1989-01-01

Written for children, this book looks at the nature of radioactive materials, how they were discovered, what they are used for and how they affect the environment around us. The emphasis is on the benefits of radioactive materials, particularly in nuclear power stations, in medical diagnostics and radiotherapy, in industry and in agriculture. Nuclear fission and fusion are explained, how radioactive materials are handled and naturally occurring radioactivity are included. (UK).

Radioactive beam diagnostics status and development at the Spiral facility

International Nuclear Information System (INIS)

Chautard, F.; Baelde, J.L.; Bucaille, F.; Duneau, P.; Galard, C.; Le Blay, J.P.; Loyant, J.M.; Martina, L.; Ulrich, M.; Laune, B.

2001-01-01

In 2001 the first radioactive beam will be accelerated in the CIME cyclotron of the SPIRAL project at GANIL. In order to be able to tune such low intensity beams in the cyclotron (down to few particles per second), a silicon and a scintillator detectors are mounted on probes. They measure the beam energy and the beam phase/RF in the cyclotron as a function of the radius. Such fragile diagnostics are meant to be used routinely from the control room by non-specialists in instrumentation and in presence of various beam intensities. Therefore, a program is developed to control and secure the acquisition procedure, the measurements and the isochronism correction. Additional detectors are installed at a fixed position in the ejection line before the experimental areas. Additionally, a diamond detector is foreseen to be installed in the machine to be tested in order to ease the CIME operation. (authors)

Production of light radioactive ion beams (RIB) using inverse kinematics

International Nuclear Information System (INIS)

Das, J.J.; Sugathan, P.; Madhavan, N.; Madhusudhana Rao, P.V.; Jhingan, A.; Varughese, T.; Barua, S.; Nath, S.; Sinha, A.K.; Kumar, B.; Zacharias, J.

2005-01-01

At Nuclear Science Centre (NSC), New Delhi, we have implemented a facility to produce low energy light radioactive ion beams (RIBs) using (p,n) type of reactions in inverse kinematics. For this purpose primary beams from the 15-UD Pelletron accelerator impinged on a thin polypropylene foil mounted on a rotating/linearly moving target assembly. For efficiently separating the secondary beam from primary beam, the existing recoil mass spectrometer (RMS) HIRA was operated with new ion optics. Suitable hardware modifications were also made. Using this facility, we have extracted a 7 Be beam of purity better than 99% and spot-size ∼4 mm in diameter. This 7 Be beam has been utilized in a variety of experiments in the energy range of 15-22 MeV. Typical beam parameters are: intensity 10 4 pps, angular spread ±30 mrad and energy spread ±0.5 MeV. Development of appropriate detector setup/target arrangement were also made to perform these experiments. In this paper, we describe the implementation of this project

Low-energy radioactive ion beam production of 22Mg

International Nuclear Information System (INIS)

Duy, N.N.; Kubono, S.; Yamaguchi, H.; Kahl, D.; Wakabayashi, Y.; Teranishi, T.; Iwasa, N.; Kwon, Y.K.; Khiem, L.H.; Kim, Y.H.; Song, J.S.; Hu, J.; Ayyad, Y.

2013-01-01

The 22 Mg nucleus plays an important role in nuclear astrophysics, specially in the 22 Mg(α,p) 25 Al and proton capture 22 Mg(p,γ) 23 Al reactions. It is believed that 22 Mg is a waiting point in the αp-process of nucleosynthesis in novae. We proposed a direct measurement of the 22 Mg+α resonance reaction in inverse kinematics using a radioactive ion (RI) beam. A 22 Mg beam of 3.73 MeV/u was produced at CRIB (Center for Nuclear Study (CNS) low-energy RI Beam) facility of the University of Tokyo located at RIKEN (Japan) in 2011. In this paper we present the results about the production of the 22 Mg beam used for the direct measurement of the scattering reaction 22 Mg(α,α) 22 Mg, and the stellar reaction 22 Mg(α,p) 25 Al in the energy region concerning an astrophysical temperature of T 9 =1–3 GK

RP process studies with radioactive beams at ATLAS

Energy Technology Data Exchange (ETDEWEB)

Rehm, K E [Argonne National Lab., Physics Div., Argonne, IL (United States)

1998-06-01

Reactions of interest to nuclear astrophysics have been studied with radioactive beams at the ATLAS accelerator. Using a modified ISOL technique, beams of {sup 18}F(T{sub 1/2}=110 min) and {sup 56}Ni(T{sub 1/2}=6.1 d) have been produced. The reactions {sup 18}F(p,{alpha}){sup 15}O, {sup 18}F(p,{gamma}){sup 19}Ne, and {sup 56}Ni(d,p){sup 57}Ni have been investigated. The results indicate that the {sup 18}F(p,{gamma}) route is a small contributor to the breakout from the hot CNO cycle into the rp process, while the {sup 56}Ni(p,{gamma}){sup 57}Cu rate is about ten times larger than previously assumed. (orig.)

JEF-2.2 radioactive decay data

International Nuclear Information System (INIS)

1994-08-01

This work deals with the JEF-2.2 radioactive decay data and is divided into four tables. The first table presents the origin of the JEF-2.2 radioactive decay data and subsequent modifications. The second one is a summary of the JEF-2.2 radioactive decay data file. The third one describes the JEF-2.2 fission products and the main decay and fission yield data. The last one consists of the main decay parameters from the JEF-2.2, ENDF/B-VI and JNDC-2.0 libraries. (O.L.). 100 figs., 4 tabs

A positive (negative) surface ionization source concept for radioactive ion beam generation

International Nuclear Information System (INIS)

Alton, G.D.; Mills, G.D.

1996-01-01

A novel, versatile, new concept, spherical-geometry, positive (negative) surface-ionization source has been designed and fabricated which will have the capability of generating both positive- and negative-ion beams without mechanical changes to the source. The source utilizes a highly permeable, high-work-function Ir ionizer (φ ≅ 5.29 eV) for ionizing highly electropositive atoms/molecules; while for negative-surface ionization, the work function is lowered by continually feeding a highly electropositive vapor through the ionizer matrix. The use of this technique to effect low work function surfaces for negative ion beam generation has the potential of overcoming the chronic poisoning effects experienced with LaB 6 while enhancing the probability for negative ion formation of atomic and molecular species with low to intermediate electron affinities. The flexibility of operation in either mode makes it especially attractive for radioactive ion beam (RIB) applications and, therefore, the source will be used as a complementary replacement for the high-temperature electron impact ionization sources presently in the use at the Holifield radioactive ion beam facility (HRIBF). The design features and operational principles of the source are described in this report. (orig.)

Neutron emission as a probe of fusion-fission and quasi-fission dynamics

International Nuclear Information System (INIS)

Hinde, D.J.

1991-01-01

Pre- and post scission neutron yeilds have been measured as a function of projectile mass, compound nucleus fissility, and fission mass-split and total kinetic energy (TKE) for 27 fusion-fission and quasi-fission reactions induced by beams of 16,18 O, 40 Ar and 64 Ni. A new method of interpretation of experimental pre-scission neutron multiplicities ν-pre and mean kinetic energies ε ν allows the extraction of fission time scales with much less uncertainty than previously, all fusion-fission results being consistent with a dynamical time scale of (35±15) x 10 -21 s for symmetric fission. All reactions show that ν-pre falls quite rapidly with increasing mass-asymmetry; evidence is presented that for fusion-fission reactions this is partly due to a reduction of the dynamical fission time scale with mass-asymmetry. For quasi-fission, the data indicate that the pre-scission multiplicity and mean neutron kinetic energy are very sensitive to the final mass-asymmetry, but that the time scale is virtually independent of mass-asymmetry. It is concluded that for fusion-fission there is no dependence of ν-pre on TKE, whilst for 64 Ni-induced quasi-fission reactions, a strong increase of ν-pre with decreasing TKE is observed, probably largely caused by neutron emission during the acceleration time of the fission fragments in these fast reactions. Interpretation of post-scission multiplicities in terms of fragment excitation energies leads to deduced time scales consistent with those determined from the pre-scission data. 54 refs., 17 tabs., 25 figs

R and D in Ciemat Nuclear Fission Department

International Nuclear Information System (INIS)

Diaz, J. L.; Diaz Arocas, P.; Gomez Briceno, D.; Gonzalez de la Huebra Gordo, A.; Gonzalez Romero, E.; Herranz Puebla, L. E.; Sola Farre, R.

2000-01-01

The technologically developed countries count on nuclear fission as a durable energy resource to produce electricity, facing the future by establishing research programmes to enhance the safety and extend the lifetime of the current power plants and to achieve the adequate management of radioactive waste. At the same time, the progress in the development of a new generation of reactors based in innovative safety concepts. The Nuclear fission Department has the ultimate objective of providing technical support to the Spanish nuclear reactors through applied research and development focused on improving the safety and performance of the operating power plants, and cooperating in the activities related to radioactive waste. In this context, the Departament has been organised in four R and D project covering the areas of Safety, Materials, Radioactive. (Author)

A concept for emittance reduction of DC radioactive heavy-ion beams

International Nuclear Information System (INIS)

Nolen, J.A.; Dooling, J.C.

1995-01-01

Numerical simulations indicate that it should be possible to use an electron beam to strip 1+ DC radioactive ion beams to 2+ or higher charge states with on the order of 50% efficiency. The device, which the authors call an Electron-Beam Charge-State Amplifier, is similar to an Electron Beam Ion Source, except that it is not pulsed, the beams are continuous. The 2+ beams are obtained in a single pass through a magnetic solenoid while higher charge states may be reached via multiple passes. An unexpected result of the ion optics simulations is that the normalized transverse emittance of the ion beam is reduced in proportion to the charge-state gain. Ion beams with realistic emittances and zero angular momentum relative to the optic axis before entering the solenoid will travel though the solenoid on helical orbits which intercept the axis once per cycle. With an ion beam about 2 mm in diameter and an electron beam about 0.2 mm in diameter, the ion stripping only occurs very near the optic axis, resulting in the emittance reduction

Measurements of Fission Cross Sections of Actinides

CERN Multimedia

Wiescher, M; Cox, J; Dahlfors, M

2002-01-01

A measurement of the neutron induced fission cross sections of $^{237}$Np, $^{241},{243}$Am and of $^{245}$Cm is proposed for the n_TOF neutron beam. Two sets of fission detectors will be used: one based on PPAC counters and another based on a fast ionization chamber (FIC). A total of 5x10$^{18}$ protons are requested for the entire fission measurement campaign.

Investigations of the neutron halo by radioactive beam experiments

International Nuclear Information System (INIS)

Mueller, A.C.

1993-01-01

Recently, a new tool has become available to study the behaviour of nuclei at the limits of particle stability. Heavy-ion projectile fragmentation, in combination with efficient recoil spectrometers, allows to prepare 'exotic' beams which can be used to induce secondary nuclear reactions. First experiments have revealed surprising features in the reactions of the most neutron-rich light nuclei. There is now conclusive evidence that the observed effects are due to long-tail matter distributions ('neutron halo') which occur for the last, very weakly bound neutrons. The results of some recent radioactive beam experiments, made by means of the spectrometer LISE3 at GANIL, are presented. (author) 24 refs.; 7 figs

Fission-fragment attachment to aerosols and their transport through capillary tubes

International Nuclear Information System (INIS)

Novick, V.J.; Alvarez, J.L.; Greenwood, R.C.

1981-01-01

The transport of radioactive aerosols was studied using equipment, collectively called the Helium jet, that has been constructed to provide basic nuclear physics data on fission product nuclides. The transport of the fission products in the system depends on their attachment to aerosol particles. The system consists of 1) a tube furnace which generates aerosols by the sublimation or evaporation of source material, 2) a helium stream used to transport the aerosols, 3) a 25 m settling tube to eliminate the larger aerosols and smaller aerosols that would deposit in the capillary, 4) a Californium-252 self-fissioning source of fission product nuclides, and 5) a small capillary to carry the radioactive aerosols from the hot cell to the laboratory. Different source materials were aerosolized but NaCl is generally used because it yielded the highest transport efficiencies through the capillary. Particle size measurments were made with NaCl aerosols by using a cascade impactor, an optical light scattering device, and the capillary itself as a diffusion battery by performing radiation measurements and/or electrical conductivity measurements. Both radioactive and nonradioactive aerosols were measured in order to investigate the possibility of a preferential size range for fission product attachment. The measured size distributions were then used to calculate attachment coefficients and finally an attachment time

Production and use of radioactive nuclear beams

International Nuclear Information System (INIS)

Tanihata, Isao

1994-01-01

Two different production method of radioactive nuclear beams (RNB) are reviewed, in this paper. One is the secondary beam method that use a high-energy heavy-ion reaction and a separator and the other is the reacceleration method. The RNB is also expected to have following properties that are useful to the application in wider research and technical usage; 1. any elements and isotopes can be used as a beam. 2. it is easy to control a position and a depth of the implantation. 3. an extremely sensitive detection is possible because they emit radiations. 4. one can select the lifetime among the isotopes suitable for a specific phenomenon. 5. one can select a spin among the isotopes for specific selectivity to the phenomenon. These useful properties of the RNB and a few recent examples of study are discussed. Among them are the discovery of the neutron skin and the neutron halo in nuclei near the limit of existence, the first determinations of reactions relevant to the synthesis of the heavy elements in the universe, and an application to the PET. (J.P.N.)

Radioactive beams produced by the ISOL method: development for laser ionization and for surface ionization; Faisceaux exotiques par methode ISOL: developpements pour l'ionisation par laser et l'ionisation de surface

Energy Technology Data Exchange (ETDEWEB)

Hosni, Faouzi

2004-10-01

The works were carried out in the framework of the research program PARRNe (production of radioactive neutron-rich nuclei). This program aims to determine optimal conditions to produce intense beams of neutron-rich isotopes. This thesis treats multiple technical aspects related to the production of separate radioactive isotopes in line (ISOL). It deals mainly with the development of the target-source unit which is the key element for projects such as SPIRAL-2 or EURISOL.The first part presents the various methods using fission as production mode and compares them: fission induced by thermal neutrons, induced by fast neutrons and photofission. The experiment carried out at CERN validated the interest of the photofission as a promising production mode of radioactive ions. That is why the institute of nuclear physics of Orsay decided to build a linear electron accelerator at the Tandem d'Orsay (ALTO).The second part of this thesis deals with the development of uranium targets. The X-rays diffraction and Scanning Electron Microscopy have been used as analysis techniques. They allowed to determine the chemical and structural characteristics of uranium carbide targets as function of various heating temperatures. After the production, the process of ionization has been studied. Two types of ion source have been worked out: the first one is a surface ion source and the second one is a source based on resonant ionization by laser. These two types of sources will be used for the ALTO project. (author)

Potential for large-scale uses for fission-product Xenon

International Nuclear Information System (INIS)

Rohrmann, C.A.

1983-03-01

Of all fission products in spent, low-enrichment-uranium power-reactor fuels, xenon is produced in the highest yield - nearly one cubic meter, STP, per metric ton. In aged fuels which may be considered for processing in the US, radioactive xenon isotopes approach the lowest limits of detection. The separation from accompanying radioactive 85 Kr is the essential problem; however, this is state-of-the-art technology which has been demonstrated on the pilot scale to yield xenon with pico-curie levels of 85 Kr contamination. If needed for special applications, such levels could be further reduced. Environmental considerations require the isolation of essentially all fission-product krypton during fuel processing. Economic restraints assure that the bulk of this krypton will need to be separated from the much-more-voluminous xenon fraction of the total amount of fission gas. Xenon may thus be discarded or made available for uses at probably very low cost. In contrast with many other fission products which have unique radioactive characteristics which make them useful as sources of heat, gamma and x-rays, and luminescence - as well as for medicinal diagnostics and therapeutics - fission-product xenon differs from naturally occurring xenon only in its isotopic composition which gives it a slightly hgiher atomic weight, because of the much higher concentrations of the 134 Xe and 136 Xe isotopes. Therefore, fission-product xenon can most likely find uses in applications which already exist but which can not be exploited most beneficially because of the high cost and scarcity of natural xenon. Unique uses would probably include applications in improved incandescent light illumination in place of krypton and in human anesthesia

Nuclear reactions with 11C and 14O radioactive ion beams

International Nuclear Information System (INIS)

Guo, Fanqing

2004-01-01

Radioactive ion beams (RIBs) have been shown to be a useful tool for studying proton-rich nuclides near and beyond the proton dripline and for evaluating nuclear models. To take full advantage of RIBs, Elastic Resonance Scattering in Inverse Kinematics with Thick Targets (ERSIKTT), has proven to be a reliable experimental tool for investigations of proton unbound nuclei. Following several years of effort, Berkeley Experiments with Accelerated Radioactive Species (BEARS), a RIBs capability, has been developed at the Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. The current BEARS provides two RIBs: a 11C beam of up to 2x108 pps intensity on target and an 14O beam of up to 3x104 pps intensity. While the development of the 11C beam has been relatively easy, a number of challenges had to be overcome to obtain the 14O beam. The excellent 11C beam has been used to investigate several reactions. The first was the 197Au(11C,xn)208-xnAt reaction, which was used to measure excitation functions for the 4n to 8n exit channels. The measured cross sections were generally predicted quite well using the fusion-evaporation code HIVAP. Possible errors in the branching ratios of ?? decays from At isotopes as well as the presence of incomplete fusion reactions probably contribute to specific overpredictions. 15F has been investigated by the p(14O,p)14O reaction with the ERSIKTT technology. Several 14O+p runs have been performed. Excellent energy calibration was obtained using resonances from the p(14N,p)14N reaction in inverse kinematics, and comparing the results to those obtained earlier with normal kinematics. The differences between 14N+p and 14O+p in the stopping power function have been evaluated for better energy calibration. After careful calibration, the energy levels of 15F were fitted with an R-matrix calculation. Spins and parities were assigned to the two observed resonances. This new measurement of the 15F ground state supports the disappearance of the Z = 8

Latest developments at GANIL for stable and radioactive ion beam production

International Nuclear Information System (INIS)

Jardin, P.; Barue, C.; Bajeat, O.; Canet, C.; Clement, E.; Cornell, J. C.; Delahaye, P.; Dubois, M.; Dupuis, M.; Flambard, J. L.; Fraanberg, H.; Frigot, R.; Leboucher, C.; Lecesne, N.; Lecomte, P.; Leherissier, P.; Lemagnen, F.; Leroy, R.; Maunoury, L.; Mery, A.

2010-01-01

In the frame of the SPIRAL II (Systeme de Production d'Ions Radioactifs Acceleres en Ligne Partie II) project, several developments of stable and radioactive ion production systems have been started up. In parallel, GANIL has the ambition to preserve the existing stable and radioactive beams and also to increase its range by offering new ones. In order to identify the best directions for this development, a new group called GANISOL has been formed. Its preliminary conclusions and the latest developments at GANIL are presented.

Progress in fission product nuclear data

International Nuclear Information System (INIS)

Lammer, M.

1983-08-01

This is the ninth issue of a report series on Fission Product Nuclear Data (FPND) which is published by the Nuclear Data Section (NDS) of the International Atomic Energy Agency (IAEA). The purpose of this series is to inform scientists working on FPND, or using such data, about all activities in this field which are planned, ongoing, or have recently been completed. The main part of this report consists of unaltered original contributions which the authors have sent to IAEA/NDS. The present issue contains also a section with some recent references relative to fission product nuclear data, which were not covered by the contributions submitted. The types of activities being included in this report are measurements, compilations and evaluations of: Fission product yields (neutron induced and spontaneous fission); Neutron reaction cross sections of fission products; Data related to the radioactive decay of fission products; Delayed neutron data of fission products; and lumped fission product data (decay heat, absorption etc.). The eighth issue of this series has been published in July 1982 as INDC(NDS)-130. The present issue includes contributions which were received by NDS between 1 August 1982 and 25 June 1983

Targets for production of high-intensity radioactive ion-beams

International Nuclear Information System (INIS)

Hagebo, E.; Hoff, P.; Steffensen, K.

1991-01-01

The recent developments of target systems for production of high intensity radioactive ion-beams at the ISOLDE mass separators is described. Methods for chemically selective production through separation of molecular ions are outlined and the effects of the addition of reactive gases has been studied. Results and further possible applications in the light element region are discussed. (author) 10 refs.; 9 figs.; 1 tab

Lifetime measurements using radioactive ion beams at intermediate energies and the Doppler shift method

Energy Technology Data Exchange (ETDEWEB)

Dewald, A.; Melon, B.; Pissulla, T.; Rother, W.; Fransen, C.; Moeller, O.; Zell, K.O.; Jolie, J. [IKP, Univ. zu Koeln (Germany); Petkov, P. [Bulg. Acad. of Science, INRNE, Solfia (Bulgaria); Starosta, K.; Przemyslaw, A.; Miller, D.; Chester, A.; Vaman, C.; Voss, P.; Gade, A.; Glasmacher, T.; Stolz, A.; Bazin, D.; Weisshaar, D. [NSCL, MSU, East Lansing (United States)

2007-07-01

Absolute transition probabilities are crucial quantities in nuclear structure physics. Therefore, it is important to establish Doppler shift (plunger) techniques also for the measurement of level lifetimes in radioactive ion beam experiments. After a first successful test of the Doppler Shift technique at intermediate energy (52MeV/u) with a stable {sup 124}Xe beam, a plunger has been built and used in two experiments, performed at the NSCL/MSU with the SEGA Ge-array and the S800 spectrometer. The aim of the first experiment was to investigate the plunger technique after a knock-out reaction using a radioactive {sup 65}Ge beam at 100 MeV/u for populating excited states in {sup 64}Ge. The second experiment aimed to measure the lifetimes of the first 2{sup +} states in {sup 110,114}Pd with the plunger technique after Coulomb excitation at beam energies of 54 MeV/u. First results of both experiments will be presented and discussed. (orig.)

Study on the calculation method of source term from fission products

International Nuclear Information System (INIS)

Zhou Jing; Gong Quan; Qiu Haifeng

2014-01-01

As a major part of radioactive nuclides, fission products play an important role in nuclear power plant design. The paper analyzes the calculation model of core activity inventory, the model of fission products releasing from the pellets to RCS, the balance model of fission products in RCS, and then proves them by calculation of the typical pressurized water reactor. The model is proved applicable for calculating fission products of pressurized water reactors. (authors)

Recent radioactive ion beam program at RIKEN and related topics

Indian Academy of Sciences (India)

Keywords. RIKEN; radioactive ion beams; magic numbers. PACS No. 21.10.-k. 1. Introduction. In RIKEN, there are several heavy ion accelerators. Main accelerator is the RIKEN ring cyclotron (RRC) with K = 540, that has been operated from 1986. The RRC has two injectors; one is heavy ion linear accelerator that has been ...

Calculated model of radioactive fission and corrosion product accumulation and distribution in a fast reactor sodium coolant circuit

International Nuclear Information System (INIS)

Kizin, V.D.; Konyashov, V.V.

1987-01-01

A simple calculation procedure of radioactive products accumulation and distribution in a primary circuit has been developed on the basis of experimental investigations at the BOR-60 reactor. Common knowledge on the impurity products transfer at the liquid-solid and liquid-gas phase boundary is taken. Use is made of the typical in reactor physics relationships for the description of the products transition to the equipment surfaces, of fission products release, metal corrosion and others. Satisfactory agreement of the calculation data with the experimental ones has been obtained. (orig.)

Feasibility of Colliding-beam fast-fission reactor via 238U80++238 U80+ --> 4 FF + 5n + 430 MeV beam with suppressed plutonium and direct conversion of fission fragment (FF) energy into electricity and/or Rocket propellant with high specific impulse

Science.gov (United States)

Maglich, Bogdan; Hester, Tim; Calsec Collaboration

2015-10-01

Uranium-uranium colliding beam experiment1, used fully ionized 238U92+ at energy 100GeV --> accelerated through 3 MV accelerator, will collide beam 240 MeV --> 4 FF + 5n + 430 MeV. Using a simple model1 fission σf ~ 100 b. Suppression of Pu by a factor of 106 will be achieved because NO thermal neutron fission can take place; only fast, 1-3 MeV, where σabs is negligible. Direct conversion of 95% of 430 MeV produced is carried by electrically charged FFs which are magnetically funneled for direct conversion of energy of FFs via electrostatic decelerators4,11. 90% of 930 MeV is electrically recoverable. Depending on the assumptions, we project electric _ power density production of 20 to 200 MWe m-3, equivalent to Thermal 1.3 - 13 GWthm-3. If one-half of unburned U is used for propulsion while rest powers system, heavy FF ion mass provides specific impulse Isp = 106 sec., 103 times higher than current rocket engines.

A high-intensity He-jet production source for radioactive beams

International Nuclear Information System (INIS)

Vieira, D.J.; Kimberly, H.J.; Grisham, D.L.; Talbert, W.L.; Wouters, J.M.; Rosenauer, D.; Bai, Y.

1993-01-01

The use of a thin-target, He-jet transport system operating with high primary beam intensities is explored as a high-intensity production source for radioactive beams. This method is expected to work well for short-lived, non-volatile species. As such the thin-target, He-jet approach represents a natural complement to the thick-target ISOL method in which such species are not, in general, rapidly released. Highlighted here is a thin-target, He-jet system that is being prepared for a 500 + μA, 800-MeV proton demonstration experiment at LAMPF this summer

Particle beam generator using a radioactive source

Science.gov (United States)

Underwood, D.G.

1993-03-30

The apparatus of the present invention selects from particles emitted by a radioactive source those particles having momentum within a desired range and focuses the selected particles in a beam having at least one narrow cross-dimension, and at the same time attenuates potentially disruptive gamma rays and low energy particles. Two major components of the present invention are an achromatic bending and focusing system, which includes sector magnets and quadrupole, and a quadrupole doublet final focus system. Permanent magnets utilized in the apparatus are constructed of a ceramic (ferrite) material which is inexpensive and easily machined.

Progress in fission product nuclear data. Information about activities in the field of measurements and compilations/evaluations of fission product nuclear data (FPND)

International Nuclear Information System (INIS)

Lammer, G.

1978-07-01

This is the fourth issue of a report series on Fission Product Nuclear Data (FPND) which is published by the Nuclear Data Section (NDS) of the International Atomic Energy Agency (IAEA). The purpose of this series is to inform scientists working on FPND, or using such data, about all activities in this field which are planned, ongoing, or have recently been completed. The main part of this report consists of unaltered original contributions which the authors have sent to IAEA/NDS. The types of activities being included in this report are measurements, compilations and evaluations of: Fission product yields (neutron induced and spontaneous fission); neutron reaction cross sections of fission products; data related to the radioactive decay of fission products; delayed neutron data of fission products; and lumped fission product data (decay heat, absorption etc.)

Preliminary shielding estimates for the proposed Oak Ridge National Laboratory (ORNL) Radioactive Ion Beam Facility (RIBF)

International Nuclear Information System (INIS)

Johnson, J.O.; Gabriel, T.A.; Lillie, R.A.

1996-01-01

The Oak Ridge National Laboratory (ORNL) has proposed designing and implementing a new target-ion source for production and injection of negative radioactive ion beams into the Hollifield tandem accelerator. This new facility, referred to as the Radioactive Ion Beam Facility (RIBF), will primarily be used to advance the scientific communities' capabilities for performing state-of-the-art cross-section measurements. Beams of protons or other light, stable ions from the Oak Ridge Isochronous Cyclotron (ORIC) will be stopped in the RIBF target ion source and the resulting radioactive atoms will be ionized, charge exchanged, accelerated, and injected into the tandem accelerator. The ORIC currently operates with proton energies up to 60 MeV and beam currents up to 100 microamps with a maximum beam power less than 2.0 kW. The proposed RIBF will require upgrading the ORIC to generate proton energies up to 200 MeV and beam currents up to 200 microamps for optimum performance. This report summarizes the results of a preliminary one-dimensional shielding analysis of the proposed upgrade to the ORIC and design of the RIBF. The principal objective of the shielding analysis was to determine the feasibility of such an upgrade with respect to existing shielding from the facility structure, and additional shielding requirements for the 200 MeV ORIC machine and RIBF target room

Neutron-induced fission cross-section measurement of 234U with quasi-monoenergetic beams in the keV and MeV range using micromegas detectors

Science.gov (United States)

Tsinganis, A.; Kokkoris, M.; Vlastou, R.; Kalamara, A.; Stamatopoulos, A.; Kanellakopoulos, A.; Lagoyannis, A.; Axiotis, M.

2017-09-01

Accurate data on neutron-induced fission cross-sections of actinides are essential for the design of advanced nuclear reactors based either on fast neutron spectra or alternative fuel cycles, as well as for the reduction of safety margins of existing and future conventional facilities. The fission cross-section of 234U was measured at incident neutron energies of 560 and 660 keV and 7.5 MeV with a setup based on `microbulk' Micromegas detectors and the same samples previously used for the measurement performed at the CERN n_TOF facility (Karadimos et al., 2014). The 235U fission cross-section was used as reference. The (quasi-)monoenergetic neutron beams were produced via the 7Li(p,n) and the 2H(d,n) reactions at the neutron beam facility of the Institute of Nuclear and Particle Physics at the `Demokritos' National Centre for Scientific Research. A detailed study of the neutron spectra produced in the targets and intercepted by the samples was performed coupling the NeuSDesc and MCNPX codes, taking into account the energy spread, energy loss and angular straggling of the beam ions in the target assemblies, as well as contributions from competing reactions and neutron scattering in the experimental setup. Auxiliary Monte-Carlo simulations were performed with the FLUKA code to study the behaviour of the detectors, focusing particularly on the reproduction of the pulse height spectra of α-particles and fission fragments (using distributions produced with the GEF code) for the evaluation of the detector efficiency. An overview of the developed methodology and preliminary results are presented.

Targets for ion sources for RIB generation at the Holifield Radioactive Ion Beam Facility

International Nuclear Information System (INIS)

Alton, G.D.

1995-01-01

The Holifield Radioactive Ion Beam Facility (HRIBF), now under construction at the Oak Ridge National Laboratory, is based on the use of the well-known on-line isotope separator (ISOL) technique in which radioactive nuclei are produced by fusion type reactions in selectively chosen target materials by high-energy proton, deuteron, or He ion beams from the Oak Ridge Isochronous Cyclotron (ORIC). Among several major challenges posed by generating and accelerating adequate intensities of radioactive ion beams (RIBs), selection of the most appropriate target material for production of the species of interest is, perhaps, the most difficult. In this report, we briefly review present efforts to select target materials and to design composite target matrix/heat-sink systems that simultaneously incorporate the short diffusion lengths, high permeabilities, and controllable temperatures required to effect maximum diffusion release rates of the short-lived species that can be realized at the temperature limits of specific target materials. We also describe the performance characteristics for a selected number of target ion sources that will be employed for initial use at the HRIBF as well as prototype ion sources that show promise for future use for RIB applications

Vitrification processes for fission product solutions

International Nuclear Information System (INIS)

Bonniaud, R.; Jouan, A.; Moncouyoux, J.P.; Sombret, C.

1982-10-01

The different processes for fission product vitrification in the world are reviewed. Continuous or discontinuous processes, induction or arc heating, in can melting or casting, tests with radioactive or simulated wastes and industrial realizations are described [fr

A new neutron counter for fission research

Energy Technology Data Exchange (ETDEWEB)

Laurent, B., E-mail: benoit.laurent@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Granier, T.; Bélier, G.; Chatillon, A.; Martin, J.-F.; Taieb, J. [CEA, DAM, DIF, F-91297 Arpajon (France); Hambsch, F.-J. [EC-JRC Institute for Reference Materials and Measurements (IRMM), Retieseweg, 2440 Geel (Belgium); Tovesson, F.; Laptev, A.B.; Haight, R.C.; Nelson, R.O.; O' Donnell, J.M. [Los Alamos Neutron Science Center, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2014-05-01

A new neutron counter for research experiments on nuclear fission has been developed. This instrument is designed for the detection of prompt fission neutrons within relatively high levels of gamma and neutron background. It is composed of a set of {sup 3}He proportional counters arranged within a block of polyethylene which serves as moderator. The detection properties have been studied by means of Monte Carlo simulations and experiments with radioactive sources. These properties are confirmed by an experiment on neutron-induced fission of {sup 238}U at the WNR facility of the Los Alamos Neutron Science Center during which the mean prompt fission neutron multiplicity, or ν{sup ¯} has been measured from 1 to 20 MeV of incident neutron energy.

Radioactivity of fission products in cistern waters along the Croatian coast of the Adriatic Sea

International Nuclear Information System (INIS)

Franic, Z.; Marovic, G.

1997-01-01

Measurements of radioactive contamination of water samples from cisterns collecting rainwater from roofs etc. with fission products have been carried out along the Croatian coast of the Adriatic Sea since 1968. An exponential decline of radioactivity followed the nuclear moratorium.After the nuclear accident at Chernobyl, higher levels of 137 Cs and 90 Sr were detected again, cistern waters being the only environmental samples in Croatia in which elevated 90 Sr activities persisted for several years. For the pre-Chernobyl period, the mean residence time of 90 Sr in cistern waters being order of magnitude several years was similar to that calculated for fallout.Contrary, for the post-Chernobyl time, S r mean residence time was calculated to be considerably shorter, reflecting the tropospheric mean residence time.Therefore, the pre-Chernobyl) and the post-Chernobyl mean residence times of 90 Sr in cistern waters reflect the mechanism by which strontium was released to the atmosphere. The annual dose for the critical adult population received from 90 Sr, 137 Cs and 90 Cs by drinking cistern water was estimated to be a few per cent of the dose from natural background radiation. (authors)

Precision Lifetime Measurements Using LaBr3 Detectors With Stable and Radioactive Beams

Directory of Open Access Journals (Sweden)

Regan P.H.

2013-12-01

Full Text Available A range of high resolution gamma-ray spectroscopy measurements have been carried out using arrays which include a number of Cerium-doped Lanthanum-Tribromide (LrBr3(Ce scintillation detectors used in conjunction with high-resolution hyper-pure germanium detectors. Examples of the spectral and temporal responses of such set-ups, using both standard point radioactive sources 152Eu and 56Co, and in-beam fusionevaporation reaction experiments for precision measurements of nuclear excited states in 34P and 138Ce are presented. The current and future use of such arrays at existing (EURICA at RIKEN and future (NUSTAR at FAIR secondary radioactive beam facilities for precision measurements of excited nuclear state lifetimes in the 10 ps to 10 ns regime are also discussed.

The potential for large scale uses for fission product xenon

International Nuclear Information System (INIS)

Rohrmann, C.A.

1983-01-01

Of all fission products in spent, low enrichment, uranium, power reactor fuels xenon is produced in the highest yield - nearly one cubic meter, STP, per metric ton. In aged fuels which may be considered for processing in the U.S. radioactive xenon isotopes approach the lowest limits of detection. The separation from accompanying radioactive 85 Kr is the essential problem; however, this is state of the art technology which has been demonstrated on the pilot scale to yield xenon with pico-curie levels of 85 Kr contamination. If needed for special applications, such levels could be further reduced. Environmental considerations require the isolation of essentially all fission product krypton during fuel processing. Economic restraints assure that the bulk of this krypton will need to be separated from the much more voluminous xenon fraction of the total amount of fission gas. Xenon may thus be discarded or made available for uses at probably very low cost. In contrast with many other fission products which have unique radioactive characteristics which make them useful as sources of heat, gamma and x-rays and luminescence as well as for medicinal diagnostics and therapeutics fission product xenon differs from naturally occurring xenon only in its isotopic composition which gives it a slightly higher atomic weight, because of the much higher concentrations of the 134 X and 136 Xe isotopes. Therefore, fission product xenon can most likely find uses in applications which already exist but which can not be exploited most beneficially because of the high cost and scarcity of natural xenon. Unique uses would probably include applications in improved incandescent light illumination in place of krypton and in human anesthesia

Study of extraterrestrial disposal of radioactive wastes. Part 3: Preliminary feasibility screening study of space disposal of the actinide radioactive wastes with 1 percent and 0.1 percent fission product contamination

Science.gov (United States)

Hyland, R. E.; Wohl, M. L.; Finnegan, P. M.

1973-01-01

A preliminary study was conducted of the feasibility of space disposal of the actinide class of radioactive waste material. This waste was assumed to contain 1 and 0.1 percent residual fission products, since it may not be feasible to completely separate the actinides. The actinides are a small fraction of the total waste but they remain radioactive much longer than the other wastes and must be isolated from human encounter for tens of thousands of years. Results indicate that space disposal is promising but more study is required, particularly in the area of safety. The minimum cost of space transportation would increase the consumer electric utility bill by the order of 1 percent for earth escape and 3 percent for solar escape. The waste package in this phase of the study was designed for normal operating conditions only; the design of next phase of the study will include provisions for accident safety. The number of shuttle launches per year required to dispose of all U.S. generated actinide waste with 0.1 percent residual fission products varies between 3 and 15 in 1985 and between 25 and 110 by 2000. The lower values assume earth escape (solar orbit) and the higher values are for escape from the solar system.

Production of a radioactive 18F ion beam for nuclear reaction studies

Science.gov (United States)

Roberts, A. D.; Nickles, R. J.; Paul, M.; Rehm, K. E.; Jiang, C. L.; Blumenthal, D. J.; Gehring, J.; Henderson, D.; Nolen, J.; Pardo, R. C.; Schiffer, J. P.; Segel, R. E.

1995-12-01

A two-stage method for generating a radioactive 18F ion beam has been developed. 18F is produced with a medical cyclotron by 11 MeV proton activation of [ 18O]water, then chemically processed off-line for use in a tandem accelerator ion source. Azeotropic distillation reduces the 18O component by 10 5, with a resulting 18O to 18F beam ratio of about 10 3. The average 18F - beam intensity per synthesis is 1 ppA over 120 min from a cesium vapor, sputter negative ion source (SNICS), with a peak intensity of 4.5 ppA.

Transcript of the workshop to discuss plans for a National High Intensity Radioactive Nuclear Beam Facility

International Nuclear Information System (INIS)

Nitschke, J.M.

1989-01-01

Following the ''First International Conference on Radioactive Nuclear Beams'' in Berkeley, a workshop was held on October 19, 1989 at the Lawrence Berkeley Laboratory to discuss plans for a National High Intensity Radioactive Nuclear Beam (RNB) Facility. The purpose of the workshop was -- after having discussed during the conference the physics question that can be addressed with RNBs -- to evaluate more concretely the possibilities for actually constructing such a facility in this country. It is becoming increasingly apparent that facility producing beams of radioactive nuclei with extreme neutron-to-proton ratios is of high scientific interest and technically feasible. It would allow the study of nuclear structure and astrophysical reactions very far from the line of stable nuclei, and could provide new possibilities of reaching the long-sought island of stability of superheavy nuclei. Such facilities are under advanced consideration in Japan and at CERN in Europe. This paper contains a slightly edited transcript of the tape recording that was made of the workshop

Fission-product release during accidents

International Nuclear Information System (INIS)

Hunt, C.E.L.; Cox, D.S.

1991-09-01

One of the aims when managing a reactor accident is to minimize the release of radioactive fission products. Release is dependent not only on the temperature, but also on the partial pressure of oxygen. Strongly oxidizing atmospheres, such as those that occurred during the Chernobyl accident, released semi-volatile elements like ruthenium, which has volatile oxides. At low temperatures, UO 2 oxidization to U 3 O 8 can result in extensive breakup of the fuel, resulting in the release of non-volatile fission products as aerosols. Under less oxidizing conditions, when hydrogen accumulates from the zirconium-water reaction, the resulting low oxygen partial pressure can significantly reduce these reactions. At TMI-2, only the noble gases and volatile fission products were released in significant quantities. A knowledge of the effect of atmosphere as well as temperature on the release of fission products from damaged reactor cores is therefore a useful, if not necessary, component of information required for accident management

Management of nontritium radioactive wastes from fusion power plants

International Nuclear Information System (INIS)

Kaser, J.D.; Postma, A.K.; Bradley, D.J.

1976-09-01

This report identifies nontritium radioactive waste sources for current conceptual fusion reactor designs. Quantities and compositions of the radwaste are estimated for the tokamaks of the University of Wisconsin (UWMAK-I), the Princeton Plasma Physics Laboratory (PPPL), and the Oak Ridge National Laboratory (ORNL); the Reference Theta Pinch Reactor of the Los Alamos Scientific Laboratory (LASL); and the Minimum Activation Blanket of the Brookhaven National Laboratory (BNL). Disposal of large amounts of radioactive waste appears necessary for fusion reactors. Although the curie (Ci) level of the wastes is comparable to that of fission products in fission reactors, the isotopes are less hazardous, and have shorter half-lives. Therefore radioactivity from fusion power production should pose a smaller risk than radioactivity from fission reactors. Radioactive waste sources identified for the five reference plants are summarized. Specific radwaste treatments or systems had to be assumed to estimate these waste quantities. Future fusion power plant conceptual designs should include radwaste treatment system designs so that assumed designs do not have to be used to assess the environmental effects of the radioactive waste

Generalized liquid drop model and fission, fusion, alpha and cluster radioactivity and superheavy nuclei

International Nuclear Information System (INIS)

Royer, G.

2012-01-01

A particular version of the liquid drop model taking into account both the mass and charge asymmetries, the proximity energy, the rotational energy, the shell and pairing energies and the temperature has been developed to describe smoothly the transition between one and two-body shapes in entrance and exit channels of nuclear reactions. In the quasi-molecular shape valley where the proximity energy is optimized, the calculated l-dependent fusion and fission barriers, alpha and cluster radioactivity half-lives as well as actinide half-lives are in good agreement with the available experimental data. In this particular deformation path, double-humped potential barriers begin to appear even macroscopically for heavy nuclear systems due to the influence of the proximity forces and, consequently, quasi-molecular isomeric states can survive in the second minimum of the potential barriers in a large angular momentum range

The Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Garrett, J.D.

1996-01-01

The status of the new Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory (ORNL), which is slated to start its scientific program late this year is discussed, as is the new experimental equipment which is being constructed at this facility. Information on the early scientific program also is given

The Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Garrett, J.D. [Oak Ridge National Lab., TN (United States)

1996-12-31

The status of the new Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory (ORNL), which is slated to start its scientific program late this year is discussed, as is the new experimental equipment which is being constructed at this facility. Information on the early scientific program also is given.

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.

A combined thermal dissociation and electron impact ionization source for radioactive ion beam generation (abstract)a

International Nuclear Information System (INIS)

Alton, G.D.; Williams, C.

1996-01-01

The probability for simultaneously dissociating and efficiently ionizing the individual atomic constituents of molecular feed materials with conventional, hot-cathode, electron-impact ion sources is low and consequently, the ion beams from these sources often appear as mixtures of several molecular sideband beams. This fragmentation process leads to dilution of the intensity of the species of interest for radioactive ion beam (RIB) applications where beam intensity is at a premium. We have conceived an ion source that combines the excellent molecular dissociation properties of a thermal dissociator and the high ionization efficiency characteristics of an electron impact ionization source that will, in principle, overcome this handicap. The source concept will be evaluated as a potential candidate for use for RIB generation at the Holifield Radioactive Ion Beam Facility, now under construction at the Oak Ridge National Laboratory. The design features and principles of operation of the source are described in this article. copyright 1996 American Institute of Physics

Prospects for high-power radioactive beam facilities worldwide

CERN Document Server

Nolen, Jerry A

2003-01-01

Advances in accelerators, targets, ion sources, and experimental instrumentation are making possible ever more powerful facilities for basic and applied research with short-lived radioactive isotopes. There are several current generation facilities, based on a variety of technologies, operating worldwide. These include, for example, those based on the in-flight method such as the recently upgraded National Superconducting Cyclotron Laboratory at Michigan State University, the facility at RIKEN in Japan, GANIL in Caen, France, and GSI in Darmstadt, Germany. Present facilities based on the Isotope-Separator On-Line method include, for example, the ISOLDE laboratory at CERN, HRIBF at Oak Ridge, and the new high-power facility ISAC at TRIUMF in Vancouver. Next-generation facilities include the Radioactive-Ion Factory upgrade of RIKEN to higher energy and intensity and the upgrade of ISAC to a higher energy secondary beam; both of these projects are in progress. A new project, LINAG, to upgrade the capabilities at...

A brief history of the Delayed'' discovery of nuclear fission

Energy Technology Data Exchange (ETDEWEB)

Holden, N.E.

1989-08-01

This year marks the Fiftieth Anniversary of the discovery of Nuclear Fission. In the early 1930's, the neutron was discovered, followed by the discovery of artificial radioactivity and then the use of the neutron to produce artificial radioactivity. The first experiments resulting in the fission of uranium took place in 1934. A paper which speculated on fission as an explanation was almost immediately published, yet no one took it seriously not even the author herself. Why did it take an additional five years before anyone realized what had occurred This is an abnormally long time in a period when discoveries, particularly in nuclear physics, seemed to be almost a daily occurrence. The events which led up to the discovery are recounted, with an attempt made to put them into their historical perspective. The role played by Mendeleev's Periodic Table, the role of the natural radioactive decay chain of uranium, the discovery of protactinium, the apparent discovery of masurium (technetium) and a speculation on the reason why Irene Curie may have missed the discovery of nuclear fission will all be discussed. 43 refs.

Overview of research by the fission group in Trombay

Indian Academy of Sciences (India)

In the late eighties, heavy-ion beams from the pelletron-based medium energy heavy- ... (9) Ternary fission/light charged particle (LCP) accompanied fission .... There is a clear deviation in the behaviour of neck emission of α-particles at high.

Measurement of g factors of excited states in radioactive beams by the transient field technique: 132Te

International Nuclear Information System (INIS)

Benczer-Koller, N.; Kumbartzki, G.; Gurdal, G; Gross, Carl J; Krieger, B; Hatarik, Robert; O'Malley, Patrick; Pain, S. D.; Segen, L.; Baktash, Cyrus; Bingham, C. R.; Danchev, M.; Grzywacz, R.; Mazzocchi, C.

2008-01-01

The g factor of the 2 1 + state in 52 132 Te, E(2 1 + ) = 0.9739 MeV, r = 2.6 ps, was measured by the transient field technique applied to a radioactive beam. The development of an experimental approach necessary for work in radioactive beam environments is described. The result g = 0.28(15) agrees with the previous measurement by the recoil-in-vacuum technique, but here the sign of the g factor is measured as well

Teaching concepts in the field of radioactivity and nuclear energy

International Nuclear Information System (INIS)

Bleichroth, W.

1982-01-01

This issue of 'Naturwissenschaften im Unterricht', dealing with the subjects of physics and chemistry, gives an account of the fundamentals of radioactivity, nuclear fission, controlled nuclear fission, nuclear power plants, dosimetry, safety engineering, shielding measures to prevent the release of radioactive substances, pressure engineering, emergency core cooling systems, waste disposal and natural and artificial environmental radioactivity. Teachers will find helpful hints as to the method of instruction and the explanation of problems. (DG) [de

Dual Neutral Particle Beam Interrogation of Intermodal Shipping Containers for Special Nuclear Material

Science.gov (United States)

Keith, Rodney Lyman

Intermodal shipping containers entering the United States provide an avenue to smuggle unsecured or stolen special nuclear material (SNM). The only direct method fielded to indicate the presence of SNM is by passive photon/neutron radiation detection. Active interrogation using neutral particle beams to induce fission in SNM is a method under consideration. One by-product of fission is the creation of fragments that undergo radioactive decay over a time period on the order of tens of seconds after the initial event. The "delayed" gamma-rays emitted from these fragments over this period are considered a hallmark for the presence of SNM. A fundamental model is developed using homogenized cargos with a SNM target embedded at the center and computationally interrogated using simultaneous neutron and photon beams. Findings from analysis of the delayed gamma emissions from these experiments are intended to mitigate the effects of poor quality information about the composition and disposition of suspect cargo before examination in an active interrogation portal.

Radioactive Ions Production Ring for Beta-Beams

CERN Document Server

Benedetto, E; Wehner, J

2010-01-01

Within the FP7 EUROnu program, Work Package 4 addresses the issues of production and acceleration of 8Li and 8B isotopes through the Beta-Beam complex, for the production of electron-neutrino. One of the major critical issues is the production of a high enougth ion ßux, to fulÞll the requirements for physics. In alternative to the direct ISOL production method, a new ap- proach is proposed in [1]. The idea is to use a compact ring for Litium ions at 25 MeV and an internal He or D target, in which the radioactive-isotopes production takes place. The beam is expected to survive for several thousands of turns, therefore cooling in 6D is required and, according this scheme, the ionization cooling provided by the target itself and a suitable RF system would be sufÞcient. We present some preliminary work on the Production ring lat- tice design and cooling issues, for the 7Li ions, and propose plans for future studies, within the EUROnu program.

Measurement of nuclear cross sections using radioactive beams; Medicion de secciones eficaces nucleares usando haces radiactivos

Energy Technology Data Exchange (ETDEWEB)

Lizcano, D.; Aguilera, E.F.; Martinez Q, E. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

2000-07-01

One of the main applications of the production and use of nuclear radioactive beams is the measurement of nuclear cross sections. In this work is used a {sup 6} He nuclear radioactive beam ({beta} emitting with half life 806.7 ms) for the study of the reaction {sup 6} + {sup 209} Bi which could have several products. This investigation was realized in collaboration with the personnel of the Nuclear Structure laboratory at the University of Notre Dame (U.S.A.) and the National institute of Nuclear Research and CONACyT by Mexico. (Author)

Description of two-proton radioactivity by the methods of the quantum theory of ternary fission

International Nuclear Information System (INIS)

Kadmenskij, S.G.

2005-01-01

Two-proton decay of spherical nuclei has been investigated on the base of the formalism of quantum mechanical theory of ternary fission. The suggested method of construction of partial two-proton-decay-width amplitudes and of asymptotics of the decaying nucleus wave functions allows to solve a problem of two-proton radioactivity description without the traditionally used in R-matrix approaches laborious sewing procedure for internal and external parent nucleus wave functions in three-body scheme. In the frame of diagonal approximation, the wave-function structure for Cooper pair of two emitted protons in parent nucleus was analyzed as well as the behavior of the wave function describing potential scattering of two-proton-decay products with taking into account decay channel coupling and properties of interaction potentials between these products [ru

Radioactive waste management and regulation

International Nuclear Information System (INIS)

Willrich, M.

1976-12-01

The following conclusions are reached: (1) safe management of post-fission radioactive waste is already a present necessity and an irreversible long-term commitment; (2) basic goals of U.S. radioactive waste policy are unclear; (3) the existing organization for radioactive waste management is likely to be unworkable if left unchanged; and (4) the existing framework for radioactive waste regulation is likely to be ineffective if left unchanged

Progress in fission product nuclear data

International Nuclear Information System (INIS)

Lammer, M.

1982-07-01

This is the eighth issue of a report series on Fission Product Nuclear Data (FPND) which is published by the Nuclear Data Section (NDS) of the International Atomic Energy Agency (IAEA). The purpose of this series is to inform scientists working on FPND, or using such data, about all activities in this field which are planned, ongoing, or have recently been completed. The main part of this report consists of unaltered original contributions which the authors have sent to IAEA/NDS. Therefore, the IAEA cannot be held responsible for the information contained nor for any consequences resulting from the use of this information. The present issue contains also a section with some recent references relative to fission product nuclear data, which were not covered by the contributions submitted. The types of activities being included in this report are measurements, compilations and evaluations of: Fission product yields (neutron induced and spontaneous fission); Neutron reaction cross sections of fission products; Data related to the radioactive decay of fission products; Delayed neutron data of fission products; and lumped fission product data (decay heat, absorption etc.). The seventh issue of this series has been published in July 1981 as INDC(NDS)-116. The present issue includes contributions which were received by NDS between 1 August 1981 and 15 June 1982

Status of the SPES-charge breeder (SPES-CB) and its beam line at INFN-LNL

International Nuclear Information System (INIS)

Galatá, Àlessio; Comunian, M.; Bellan, L.; Maggiore, M.; Patti, G.; Roncolato, C.; Bisoffi, G.; Russo, A.D.; Calabretta, L.; Angot, J.; Lamy, T.

2016-01-01

The Selective Production of Exotic Species (SPES) facility is under construction at INFN-LNL: aim of this project is the production, ionization and post-acceleration of radioactive ions to perform forefront research in nuclear physics. Radioactive species will be produced by fissions induced by a proton beam impinging on an UC_x target: the proton beam will be delivered by a room temperature cyclotron (built by the Best Company) with a maximum energy of 40 MeV and 0.25 mA of maximum current. The radioactive species produced in the Target-Ion-Source system, extracted as a 1+ beam, cooled in a RFQ-cooler and purified from the isobars contaminants through a High Resolution Mass Spectrometer (HRMS). In order to allow post acceleration with the superconducting linac ALPI at INFN-LNL (up to 10 MeV/A for A/q = 7), an ECR-based charge breeding technique (ECR-CB) was chosen: in particular the SPES-CB was developed by the LPSC Grenoble on the basis of the Phoenix booster. The SPES-CB will be equipped with a complete test bench, totally integrated with the SPES beam line: in particular, in order to avoid beam contaminations induced by the impurities present inside the SPES-CB, and to have high transmission for a beam of very low intensity, special attention was paid not only to the transport efficiency but also to the resolution of the spectrometer downstream the charge breeder, with the design of a Medium Resolution Mass Spectrometer (MRMS). In the following paper the technical aspects connected with SPES-CB, its beam line and the transport of highly charged radioactive ions will be described.

Status of the SPES-charge breeder (SPES-CB) and its beam line at INFN-LNL

Energy Technology Data Exchange (ETDEWEB)

Galatá, Àlessio; Comunian, M. [INFN-Laboratori Nazionali di Legnaro, Viale dell’Universitá 2, 35020 Legnaro, Padova (Italy); Bellan, L. [INFN-Laboratori Nazionali di Legnaro, Viale dell’Universitá 2, 35020 Legnaro, Padova (Italy); Dipartimento di Fisica e Astronomia, Universitá degli Studi di Padova e Sezione INFN, Padova (Padova) (Italy); Maggiore, M.; Patti, G.; Roncolato, C.; Bisoffi, G. [INFN-Laboratori Nazionali di Legnaro, Viale dell’Universitá 2, 35020 Legnaro, Padova (Italy); Russo, A.D.; Calabretta, L. [INFN-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy); Angot, J.; Lamy, T. [LPSC – Université Grenoble Alpes – CNRS/IN2P3, 53 rue des Martyrs, 38026 Grenoble Cedex (France)

2016-06-01

The Selective Production of Exotic Species (SPES) facility is under construction at INFN-LNL: aim of this project is the production, ionization and post-acceleration of radioactive ions to perform forefront research in nuclear physics. Radioactive species will be produced by fissions induced by a proton beam impinging on an UC{sub x} target: the proton beam will be delivered by a room temperature cyclotron (built by the Best Company) with a maximum energy of 40 MeV and 0.25 mA of maximum current. The radioactive species produced in the Target-Ion-Source system, extracted as a 1+ beam, cooled in a RFQ-cooler and purified from the isobars contaminants through a High Resolution Mass Spectrometer (HRMS). In order to allow post acceleration with the superconducting linac ALPI at INFN-LNL (up to 10 MeV/A for A/q = 7), an ECR-based charge breeding technique (ECR-CB) was chosen: in particular the SPES-CB was developed by the LPSC Grenoble on the basis of the Phoenix booster. The SPES-CB will be equipped with a complete test bench, totally integrated with the SPES beam line: in particular, in order to avoid beam contaminations induced by the impurities present inside the SPES-CB, and to have high transmission for a beam of very low intensity, special attention was paid not only to the transport efficiency but also to the resolution of the spectrometer downstream the charge breeder, with the design of a Medium Resolution Mass Spectrometer (MRMS). In the following paper the technical aspects connected with SPES-CB, its beam line and the transport of highly charged radioactive ions will be described.

First radioactive beams at ACCULINNA-2 facility and first proposed experiment

Science.gov (United States)

Bezbakh, A. A.; Beekman, W.; Chudoba, V.; Fomichev, A. S.; Golovkov, M. S.; Gorshkov, A. V.; Grigorenko, L. V.; Kaminski, G.; Krupko, S. A.; Mentel, M.; Nikolskii, E. Yu.; Parfenova, Yu. L.; Plucinski, P.; Sidorchuk, S. I.; Slepnev, R. S.; Sharov, P. G.; Ter-Akopian, G. M.; Zalewski, B.

2018-04-01

New fragment separator ACCULINNA-2 was installed at the primary beam line of the U-400M cyclotron in 2016. Recently, first radioactive ion beams were obtained. The design parameters of new facility were experimentally confirmed. Intensity, purity and transverse profile of several secondary beams at the final focal plane were studied. The intensities obtained for the secondary beams of 14B, 12Be, 9;11Li, 6;8He in the fragmentation reaction 15N (49.7 AMeV) + Be (2 mm) are in average 15 times higher in comparison to the ones produced at its forerunner ACCULINNA separator. The ACCULINNA-2 separator will become a backbone facility at the FLNR for the research in the field of light exotic nuclei in the vicinity of the nuclear drip lines. The planned first experiment, aimed for the observation of the 7H nucleus at ACCULINNA-2, is outlined.

Investigating the contamination of accelerated radioactive beams with an ionization chamber at MINIBALL

CERN Document Server

Zidarova, Radostina

2017-01-01

My summer student project involved the operation and calibration of an ionization chamber, which was used at MINIBALL for investigating and determining the contamination in post-accelerated radioactive beams used for Coulomb excitation and transfer reaction experiments.

Radioactive ion beam production by the ISOL method for SPIRAL

International Nuclear Information System (INIS)

Landre-Pellemoine, Frederique

2001-01-01

This work is directly related to the SPIRAL project (Systeme de Production d'Ions Radioactifs Acceleres en Lignes) of which the start up will begin in September 2001 at GANIL (Grand Accelerateur National d'Ions Lourds) in Caen. This thesis primarily concerns the development of radioactive ion production systems (target/ion source) by the thorough study of each production stage of the ISOL (Isotopic Separation On Line) method: target and/or projectile fragmentation production, diffusion out of target material, effusion into the ion source and finally the ionization of the radioactive atoms. A bibliographical research and thermal simulations allowed us to optimize materials and the shape of the production and diffusion targets. A first target was optimized and made reliable for the radioactive noble gases production (argon, neon...). A second target dedicated to the radioactive helium production was entirely designed and realised (from the specifications to the 'off line' and 'on line' tests). Finally, a third target source system was defined for singly-charged radioactive alkaline production. The intensities of secondary beams planned for SPIRAL are presented here. A detailed study of the diffusion effusion efficiency for these various targets showed that the use of a fine microstructure carbon (grain size of 1 μm) improved the diffusion and showed the importance of thickness of the lamella for the short lived isotope effusion. (author) [fr

Thin and thick targets for radioactive ion beam production at SPIRAL1 facility

Science.gov (United States)

Jardin, P.; Bajeat, O.; Delahaye, P.; Dubois, M.; Kuchi, V.; Maunoury, L.

2018-05-01

The upgrade of the Système de Production d'Ions Radioactifs Accélérés en Ligne (SPIRAL1) facility will deliver its new Radioactive Ion Beams (RIB) by summer 2017. The goal of the upgrade is an improvement of the performances of the installation in terms of isotopes species and ion charge states [1]. Ion beams are produced using the Isotope Separator On Line Method, consisting in an association of a primary beam of stable ions, a hot target and an ion source. The primary beam impinges on the material of the target. Radioactive isotopes are produced by nuclear reactions and propagate up to the source, where they are ionized and accelerated to create a RIB. One advantage of SPIRAL1 driver is the variety of its available primary beams, from carbon to uranium with energies up to 95 MeV/A. Within the SPIRAL1 upgrade, they will be combined with targets made of a large choice of materials, extending in this way the number of possible nuclear reactions (fusion-evaporation, transfer, fragmentation) for producing a wider range of isotopes, up to regions of the nuclide chart still scarcely explored. Depending on the reaction process, on the collision energy and on the primary beam power, thin and thick targets are used. As their functions can be different, their design must cope with specific constraints which will be described. After a presentation of the goals of present and future SPIRAL1 Target Ion Source System, the main target features, studies and designs under progress are presented.

Experimental methods in radioactive ion-beam target/ion source development and characterization

International Nuclear Information System (INIS)

Welton, R.F.; Alton, G.D.; Cui, B.; Murray, S.N.

1998-01-01

We have developed off-line experimental techniques and apparatuses that permit direct measurement of effusive-flow delay times and ionization efficiencies for nearly any chemically reactive element in high-temperature target/ion sources (TIS) commonly used for on-line radioactive ion-beam (RIB) generation. The apparatuses include a hot Ta valve for effusive-flow delay-time measurements, a cooled molecular injection system for determination of ionization efficiencies, and a gas flow measurement/control system for introducing very low, well-defined molecular flows into the TIS. Measurements are performed on a test stand using molecular feed compounds containing stable complements of the radioactive nuclei of interest delivered to the TIS at flow rates commensurate with on-line RIB generation. In this article, the general techniques are described and effusive-flow delay times and ionization efficiency measurements are reported for fluorine in an electron-beam plasma target/ion source developed for RIB generation and operated in both positive- and negative-ion extraction modes. copyright 1998 American Institute of Physics

Radioactive ion beam facility at Louvain-La-Neuve, Belgium and its features

International Nuclear Information System (INIS)

Chintalapudi, S.N.

1991-01-01

Use of radioactive ion beams for the study of nuclear structure as well as the astrophysical reaction cross sections become the current interest in physics. A full-fledged facility based on two coupled cyclotrons comprising a compact high current cyclotron and a medium energy cyclotron with an intermediate target and ion source system has been recently commissioned at the Louvain-La-Neuve University in Belgium by its accelerator group and has been successfully used for the measurement of cross sections for the primordial nucleosynthesis reactions of astrophysical interest, directly. A brief description of the system, its operational features together with some details of the target and the ion source arrangement for the production of the radioactive ion beams and their acceleration to energies required for the proposed studies is presented. Description of the reactions studied by the Louvain La Neuve group for astrophysical interest is also given. (author). 20 refs., 6 figs., 4 tabs

Proceedings of the workshop on the science of intense radioactive ion beams

International Nuclear Information System (INIS)

McClelland, J.B.; Vieira, D.J.

1990-10-01

This report contains the proceedings of a 2-1/2 day workshop on the Science of Intense Radioactive Ion Beams which was held at the Los Alamos National Laboratory on April 10--12, 1990. The workshop was attended by 105 people, representing 30 institutions from 10 countries. The thrust of the workshop was to develop the scientific opportunities which become possible with a new generation intense Radioactive Ion Beam (RIB) facility, currently being discussed within North America. The workshop was organized around five primary topics: (1) reaction physics; (2) nuclei far from stability/nuclear structure; (3) nuclear astrophysics; (4) atomic physics, material science, and applied research; and (5) facilities. Overview talks were presented on each of these topics, followed by 1-1/2 days of intense parallel working group sessions. The final half day of the workshop was devoted to the presentation and discussion of the working group summary reports, closing remarks and a discussion of future plans for this effort

Proceedings of the workshop on the science of intense radioactive ion beams

Energy Technology Data Exchange (ETDEWEB)

McClelland, J.B.; Vieira, D.J. (comps.)

1990-10-01

This report contains the proceedings of a 2-1/2 day workshop on the Science of Intense Radioactive Ion Beams which was held at the Los Alamos National Laboratory on April 10--12, 1990. The workshop was attended by 105 people, representing 30 institutions from 10 countries. The thrust of the workshop was to develop the scientific opportunities which become possible with a new generation intense Radioactive Ion Beam (RIB) facility, currently being discussed within North America. The workshop was organized around five primary topics: (1) reaction physics; (2) nuclei far from stability/nuclear structure; (3) nuclear astrophysics; (4) atomic physics, material science, and applied research; and (5) facilities. Overview talks were presented on each of these topics, followed by 1-1/2 days of intense parallel working group sessions. The final half day of the workshop was devoted to the presentation and discussion of the working group summary reports, closing remarks and a discussion of future plans for this effort.

Fusion reactor radioactive waste management

International Nuclear Information System (INIS)

Kaser, J.D.; Postma, A.K.; Bradley, D.J.

1976-01-01

Quantities and compositions of non-tritium radioactive waste are estimated for some current conceptual fusion reactor designs, and disposal of large amounts of radioactive waste appears necessary. Although the initial radioactivity of fusion reactor and fission reactor wastes are comparable, the radionuclides in fusion reactor wastes are less hazardous and have shorter half-lives. Areas requiring further research are discussed

Independent yields of Rb and Cs isotopes from thermal-neutron induced fission of 235U

International Nuclear Information System (INIS)

Balestrini, S.J.; Decker, R.; Wollnik, H.; Wuensch, K.D.; Jung, G.; Koglin, E.; Siegert, G.

1979-01-01

The relative yields of Rb and Cs isotopes from thermal-neutron fission of 235 U have been redetermined using the mass separator OSTIS, on-line at a neutron guide of the High-Flux Beam Reactor at the Institut Laue-Langevin, Grenoble, France. The separator ion source was a hot oven containing 235 U in a graphite matrix. The neutron beam was pulsed. Alkali fission products diffused out of the graphite and were ionized, thus producing a stepwise increase in the analyzed ion beam proportional to the independent fission yield. The ion beam and the fissions in the source were monitored simultaneously. The diffusion of Rb and Cs from the source was exponential in time with half-lives ranging from 2.8 to 18 sec, depending upon the element and source temperature. The independent fission yields of Rb and Cs are normalized by equating their element yields to each other and to a value computed from the charge distributions observed with the recoil separator LOHENGRIN and well established mass yields. Fractional independent yields are deduced from the independent fission yields, and these compare very well with the EOZ model described by Wahl

A high-efficiency positive (negative) surface ionization source for radioactive ion beam (abstract)a

International Nuclear Information System (INIS)

Alton, G.D.; Mills, G.D.

1996-01-01

A versatile, new concept, spherical-geometry, positive (negative) surface-ionization source has been designed and fabricated which will have the capability of generating both positive- and negative-ion beams without mechanical changes to the source. The source utilizes a highly permeable, high-work-function Ir ionizer (φ≡5.29 eV) for ionizing highly electropositive atoms/molecules; while for negative-surface ionization, the work function is lowered to φ≡1.43 eV by continually feeding cesium vapor through the ionizer matrix. The use of this technique for negative ion beam generation has the potential of overcoming the chronic poisoning effects experienced with LaB 6 while enhancing considerably the efficiency for negative surface ionization of atoms and molecules with intermediate electron affinities. The flexibility of operation in either mode makes it especially attractive for radioactive ion beam applications and, therefore, the source will be used as a complementary replacement for the high-temperature electron impact ionization sources presently in use at the Holifield radioactive beam facility. The design features and operational principles of the source will be described in this report. copyright 1996 American Institute of Physics

Measurement of the fission yields of selected prompt and decay fission product gamma-rays of spontaneously fissioning 252Cf and 244Cm

International Nuclear Information System (INIS)

Reber, E.L.; Gehrke, R.J.; Aryaeinejad, R.; Hartwell, J.K.

2005-01-01

Gamma-ray spectrometry measurements have been made of the fission yields of selected γ -rays emitted by the spontaneously fissioning isotopes 252 Cf and 244 Cm. The measured γ-rays were selected based on their relative abundance in the spectrum and their freedom from interference or, in a few instances, ease of interference correction. From these data and the cumulative and independent yield data of England and Rider, those γ-rays that are primarily produced by radioactive decay, as opposed to direct yield, were converted into the decays per spontaneous fission expressed in percent and compared to cumulative yield values of England and Rider. For those γ-rays whose production is dominated by direct (independent) yield, the ratio of γ-rays per spontaneous fission is reported. The γ-ray yield can be compared to the independent yield values of England and Rider when 100% of the direct feeding passes through the γ-ray. In those cases where both cumulative and independent yields contribute to the observed γ-ray emission rate, a direct comparison is not possible but a method to quantify the contribution from each is proposed. (author)

The Munich accelerator for fission fragments MAFF

International Nuclear Information System (INIS)

Habs, D.; Gross, M.; Assmann, W.; Ames, F.; Bongers, H.; Emhofer, S.; Heinz, S.; Henry, S.; Kester, O.; Neumayr, J.; Ospald, F.; Reiter, P.; Sieber, T.; Szerypo, J.; Thirolf, P.G.; Varentsov, V.; Wilfart, T.; Faestermann, T.; Kruecken, R.; Maier-Komor, P.

2003-01-01

The Munich Accelerator for Fission Fragments MAFF has been designed for the new Munich research reactor FRM-II. It will deliver several intense beams (∼3x10 11 s -1 ) of very neutron-rich fission fragments with a final energy of 30 keV (low-energy beam) or energies between 3.7 and 5.9 MeV·A (high-energy beam). Such beams are of interest for the creation of super-heavy elements by fusion reactions, nuclear spectroscopy of exotic nuclei, but they also have a potential for applications, e.g. in medicine. Presently the Munich research reactor FRM-II is ready for operation, but authorities delay the final permission to turn the reactor critical probably till the end of 2002. Only after this final permission the financing of the major parts of MAFF can start. On the other hand all major components have been designed and special components have been tested in separate setups

Nuclear fission induced by heavy ions

International Nuclear Information System (INIS)

Newton, J.O.

1988-09-01

Because the accelerators of the 50's and 60's mostly provided beams of light ions, well suited for studying individual quantum states of low angular momentum or reactions involving the transfer of one or two nucleons, the study of fission, being an example of large-scale collective motion, has until recently been outside of the mainstream of nuclear research. This situation has changed in recent years, due to the new generation of accelerators capable of producing beams of heavy ions with energies high enough to overcome the Coulomb barriers of all stable nuclei. These have made possible the study of new examples of large-scale collective motions, involving major rearrangements of nuclear matter, such as deep-inelastic collisions and heavy-ion fusion. Perhaps the most exciting development in the past few years is the discovery that dissipative effects (nuclear viscosity) play an important role in fission induced by heavy ions, contrary to earlier assumptions that the viscosity involved in fission was very weak and played only a minor role. This review will be mainly concerned with developments in heavy-ion induced fission during the last few years and have an emphasis on the very recent results on dissipative effects. Since heavy-ion bombardment usually results in compound systems with high excitation energies and angular momenta, shell effects might be expected to be small, and the subject of low energy fission, where they are important, will not be addressed. 285 refs., 58 figs

Libraries of decay data and fission product yields in the ABBN-93 constant set

International Nuclear Information System (INIS)

Zabrodskaya, S.V.; Nikolaev, M.N.; Tsibulya, A.M.

2001-01-01

This paper describes three new libraries in the Abb. constant set which are essential for calculating radioactivity: basic decay data, radioactive decay photon spectra and fission product yields. (author)

Fission cross section measurements at intermediate energies

International Nuclear Information System (INIS)

Laptev, Alexander

2005-01-01

The activity in intermediate energy particle induced fission cross-section measurements of Pu, U isotopes, minor actinides and sub-actinides in PNPI of Russia is reviewed. The neutron-induced fission cross-section measurements are under way in the wide energy range of incident neutrons from 0.5 MeV to 200 MeV at the GNEIS facility. In number of experiments at the GNEIS facility, the neutron-induced fission cross sections were obtained for many nuclei. In another group of experiments the proton-induced fission cross-section have been measured for proton energies ranging from 200 to 1000 MeV at 100 MeV intervals using the proton beam of PNPI synchrocyclotron. (author)

Recoil separators for radiative capture using radioactive ion beams. Recent advances and detection techniques

Energy Technology Data Exchange (ETDEWEB)

Ruiz, Chris [TRIUMF, Vancouver, BC (Canada); Greife, Uwe; Hager, Ulrike [Colorado School of Mines, Golden, CO (United States)

2014-06-15

Radiative capture reactions involving the fusion of hydrogen or helium are ubiquitous in the stellar history of the universe, and are some of the most important reactions in the processes that govern nucleosynthesis and energy generation in both static and explosive scenarios. However, radiative capture reactions pose some of the most difficult experimental challenges due to extremely small cross sections. With the advent of recoil separators and techniques in inverse kinematics, it is now possible to measure radiative capture reactions on very short-lived radioactive nuclei, and in the presence of high experimental backgrounds. In this paper we review the experimental needs for making measurements of astrophysical importance on radiative capture reactions. We also review some of the important historical advances in the field of recoil separators as well as describe current techniques and performance milestones, including descriptions of some of the separators most recently working at radioactive ion beam facilities, such as DRAGON at TRIUMF and the DRS at the Holifield Radioactive Ion Beam Facility. We will also summarize some of the scientific highlight measurements at the RIB facilities. (orig.)

Estimation of penetration depth of fission products in cladding Hull

International Nuclear Information System (INIS)

Kim, Hee Moon; Jung, Yang Hong; Yoo, Byong Ok; Choo, Yong Sun; Hong, Kwon Pyo

2005-01-01

A disposal and a reprocessing for spent fuel rod with high burnup need de-cladding procedure. Pellet in this rod has been separated from a cladding hull to reduce a radioactivity of hull by chemical and mechanical methods. But fission products and actinides(U,Pu) still remain inside of cladding hull by chemical bonding and fission spike, which is called as 'contamination'. More specific removal of this contamination would have been considered. In this study, the sorts of fission products and penetration depth in hull were observed by EPMA test. To analyze this behavior, SRIM 2000 code was also used as energies of fission products and an oxide thickness of hull

The Radioactive Ion Beams in Brazil (RIBRAS) facility. Description, program, main results, future plans

Science.gov (United States)

Lépine-Szily, A.; Lichtenthäler, R.; Guimarães, V.

2014-08-01

RIBRAS (Radioactive Ion Beams in Brazil) is a facility installed at the Institute of Physics of the University of São Paulo (IFUSP), Brazil. The RIBRAS system consists of two superconducting solenoids and uses the "in-flight method" to produce radioactive ion beams using the primary beam provided by the 8UD Pelletron Tandem of IFUSP. The ion beams produced so far by RIBRAS are 6He, 8Li, 7Be, 10Be, 8B, 12B with intensities that can vary from 104 to 106 pps. Initially the experimental program covered the study of elastic and inelastic scattering with the objective to study the interaction potential and the reaction mechanisms between weakly bound (RIB) and halo (6He and 8B projectiles on light, medium and heavy mass targets. With highly purified beams, the study of resonant elastic scattering and resonant transfer reactions, using inverse kinematics and thick targets, has also been included in our experimental program. Also, transfer reactions of astrophysical interest and fusion reactions induced by halo nuclei are part of the near-future research program. Our recent results on elastic scattering, alpha-particle production and total reaction cross sections, as well as the resonant elastic and transfer reactions, are presented. Our plans for the near future are related to the installation of a new beam line and a cave for gamma-ray detection. We intend to place in operation a large area neutron detector available in our laboratory. The long-range plans could be the move of the RIBRAS system to the more energetic beam line of the LINAC post-accelerator (10MeV/nucleon primary beams) still in construction in our laboratory.

1: the atom. 2: radioactivity. 3: man and radiations. 4: the energy. 5: nuclear energy: fusion and fission. 6: the operation of a nuclear reactor. 7: the nuclear fuel cycle; 1: l'atome. 2: la radioactivite. 3: l'homme et les rayonnements. 4: l'energie. 5: l'energie nucleaire: fusion et fission. 6: le fonctionnement d'un reacteur nucleaire. 7: le cycle du combustible nucleaire

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-07-01

This series of 7 digest booklets present the bases of the nuclear physics and of the nuclear energy: 1 - the atom (structure of matter, chemical elements and isotopes, the four fundamental interactions, nuclear physics); 2 - radioactivity (definition, origins of radioelements, applications of radioactivity); 3 - man and radiations (radiations diversity, biological effects, radioprotection, examples of radiation applications); 4 - energy (energy states, different forms of energy, characteristics); 5 - nuclear energy: fusion and fission (nuclear energy release, thermonuclear fusion, nuclear fission and chain reaction); 6 - operation of a nuclear reactor (nuclear fission, reactor components, reactor types); 7 - nuclear fuel cycle (nuclear fuel preparation, fuel consumption, reprocessing, wastes management). (J.S.)

LOFC fission product release and circulating activity calculations for gas-cooled reactors

International Nuclear Information System (INIS)

Apperson, C.E. Jr.; Carruthers, L.M.; Lee, C.E.

1977-01-01

The inventories of fission products in a gas-cooled reactor under accident and normal steady state conditions are time and temperature dependent. To obtain a reasonable estimate of these inventories it is necessary to consider fuel failure, a temperature dependent variable, and radioactive decay, a time dependent variable. Using arbitrary radioactive decay chains and published fuel failure models for the High Temperature Gas-Cooled Reactor (HTGR), methods have been developed to evaluate the release of fission products during the Loss of Forced Circulation (LOFC) accident and the circulating and plateout fission product inventories during steady state non-accident operation. The LARC-2 model presented here neglects the time delays in the release from the HTGR due to diffusion of fission products from particles in the fuel rod through the graphite matrix. It also neglects the adsorption and evaporation process of metallics at the fuel rod-graphite and graphite-coolant hole interfaces. Any time delay due to the finite time of transport of fission products by convection through the coolant to the outside of the prestressed concrete reactor vessel (PCRV) is also neglected. This model assumes that all fission products released from fuel particles are immediately deposited outside the PCRV with no time delay

The Holifield Radioactive Ion Beam Facility at the Oak Ridge National Laboratory: Present status and future plans

International Nuclear Information System (INIS)

Alton, G.D.; Beene, J.R.

1998-01-01

The Holifield Radioactive Ion Beam Facility (HRIBF) is a first generation national user facility for nuclear physics and nuclear astrophysics research with radioactive ion beams (RIBs). The reconfiguration, construction, and equipment commissioning phases have been completed and the beam development program is in progress. In this article, descriptions of the facility and newly implemented experimental equipment for use in the nuclear and astrophysics programs will be given and an outline of the initial experimental program will be presented. Special target ion source related problems, endemic to the production of specific short lived RIBs will be discussed. In addition, plans, which involve either a 200 MeV or a 1 GeV proton linac driver for a second generation ISOL facility, will be presented

Criteria for selection of target materials and design of high-efficiency-release targets for radioactive ion beam generation

CERN Document Server

Alton, G D; Liu, Y

1999-01-01

In this report, we define criteria for choosing target materials and for designing, mechanically stable, short-diffusion-length, highly permeable targets for generation of high-intensity radioactive ion beams (RIBs) for use at nuclear physics and astrophysics research facilities based on the ISOL principle. In addition, lists of refractory target materials are provided and examples are given of a number of successful targets, based on these criteria, that have been fabricated and tested for use at the Holifield Radioactive Ion Beam Facility (HRIBF).

Independent yields of Rb and Cs isotopes from thermal-neutron induced fission of /sup 235/U

Energy Technology Data Exchange (ETDEWEB)

Balestrini, S.J.; Decker, R.; Wollnik, H.; Wuensch, K.D.; Jung, G.; Koglin, E.; Siegert, G.

1979-12-01

The relative yields of Rb and Cs isotopes from thermal-neutron fission of /sup 235/U have been redetermined using the mass separator OSTIS, on-line at a neutron guide of the High-Flux Beam Reactor at the Institut Laue-Langevin, Grenoble, France. The separator ion source was a hot oven containing /sup 235/U in a graphite matrix. The neutron beam was pulsed. Alkali fission products diffused out of the graphite and were ionized, thus producing a stepwise increase in the analyzed ion beam proportional to the independent fission yield. The ion beam and the fissions in the source were monitored simultaneously. The diffusion of Rb and Cs from the source was exponential in time with half-lives ranging from 2.8 to 18 sec, depending upon the element and source temperature. The independent fission yields of Rb and Cs are normalized by equating their element yields to each other and to a value computed from the charge distributions observed with the recoil separator LOHENGRIN and well established mass yields. Fractional independent yields are deduced from the independent fission yields, and these compare very well with the EOZ model described by Wahl.

Proceedings of the workshop on the production and use of intense radioactive beams at the Isospin Laboratory

International Nuclear Information System (INIS)

Garrett, J.D.

1992-01-01

These proceedings report the deliberations of a 3 1/2 day workshop on the Production and Use of Intense Radioactive Ion Beams at the Isospin Laboratory, which was held at the Joint Institute for Heavy Ion Research in Oak Ridge, Tennessee, October 1992. The purpose of this workshop was not to duplicate the programs of other recent radioactive ion beam workshops or international conferences that have focused on the scientific concepts which radioactive beams can, and in fact already are, addressing. Instead, the intent was to address the technical problems associated with the construction of the next generation ISOL facility and to initiate a discussion of the type of experimental equipment that should be developed for such a facility. We have tried to bring together in Oak Ridge the world's experts in radioactive targets/ion sources, light and heavy-ion accelerators, and detection systems. After 1 1/2 days of overview presentations, the participants divided into three discussion groups (Experiments with Radioactive Beams, Target Ion Sources and Mass Separation, and Accelerators-Primary and Secondary) for 1 1/2 days of detailed discussions of the most pertinent issues. The final session was devoted to reports from each of the discussion groups and a general discussion of where to go from here. An outgrowth of these discussions was the establishment of working groups to coordinate future technical developments associated with the pertinent issues. The proceedings include the text of all the overview presentations, reports from each discussion group, as well as contributions from those participants who chose to provide the text of their presentations in the discussion groups and the Concluding Remarks. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database

Proceedings of the workshop on the production and use of intense radioactive beams at the Isospin Laboratory

Energy Technology Data Exchange (ETDEWEB)

Garrett, J.D. [ed.

1992-12-31

These proceedings report the deliberations of a 3 1/2 day workshop on the Production and Use of Intense Radioactive Ion Beams at the Isospin Laboratory, which was held at the Joint Institute for Heavy Ion Research in Oak Ridge, Tennessee, October 1992. The purpose of this workshop was not to duplicate the programs of other recent radioactive ion beam workshops or international conferences that have focused on the scientific concepts which radioactive beams can, and in fact already are, addressing. Instead, the intent was to address the technical problems associated with the construction of the next generation ISOL facility and to initiate a discussion of the type of experimental equipment that should be developed for such a facility. We have tried to bring together in Oak Ridge the world`s experts in radioactive targets/ion sources, light and heavy-ion accelerators, and detection systems. After 1 1/2 days of overview presentations, the participants divided into three discussion groups (Experiments with Radioactive Beams, Target Ion Sources and Mass Separation, and Accelerators-Primary and Secondary) for 1 1/2 days of detailed discussions of the most pertinent issues. The final session was devoted to reports from each of the discussion groups and a general discussion of where to go from here. An outgrowth of these discussions was the establishment of working groups to coordinate future technical developments associated with the pertinent issues. The proceedings include the text of all the overview presentations, reports from each discussion group, as well as contributions from those participants who chose to provide the text of their presentations in the discussion groups and the Concluding Remarks. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

Code Development on Fission Product Behavior under Severe Accident-Validation of Aerosol Sedimentation

International Nuclear Information System (INIS)

Ha, Kwang Soon; Kim, Sung Il; Jang, Jin Sung; Kim, Dong Ha

2016-01-01

The gas and aerosol phases of the radioactive materials move through the reactor coolant systems and containments as loaded on the carrier gas or liquid, such as steam or water. Most radioactive materials might escape in the form of aerosols from a nuclear power plant during a severe reactor accident, and it is very important to predict the behavior of these radioactive aerosols in the reactor cooling system and in the containment building under severe accident conditions. Aerosols are designated as very small solid particles or liquid droplets suspended in a gas phase. The suspended solid or liquid particles typically have a range of sizes of 0.01 m to 20 m. Aerosol concentrations in reactor accident analyses are typically less than 100 g/m3 and usually less than 1 g/m3. When there are continuing sources of aerosol to the gas phase or when there are complicated processes involving engineered safety features, much more complicated size distributions develop. It is not uncommon for aerosols in reactor containments to have bimodal size distributions for at least some significant periods of time early during an accident. Salient features of aerosol physics under reactor accident conditions that will affect the nature of the aerosols are (1) the formation of aerosol particles, (2) growth of aerosol particles, (3) shape of aerosol particles. At KAERI, a fission product module has been developed to predict the behaviors of the radioactive materials in the reactor coolant system under severe accident conditions. The fission product module consists of an estimation of the initial inventories, species release from the core, aerosol generation, gas transport, and aerosol transport. The final outcomes of the fission product module designate the radioactive gas and aerosol distribution in the reactor coolant system. The aerosol sedimentation models in the fission product module were validated using ABCOVE and LACE experiments. There were some discrepancies on the predicted

Code Development on Fission Product Behavior under Severe Accident-Validation of Aerosol Sedimentation

Energy Technology Data Exchange (ETDEWEB)

Ha, Kwang Soon; Kim, Sung Il; Jang, Jin Sung; Kim, Dong Ha [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The gas and aerosol phases of the radioactive materials move through the reactor coolant systems and containments as loaded on the carrier gas or liquid, such as steam or water. Most radioactive materials might escape in the form of aerosols from a nuclear power plant during a severe reactor accident, and it is very important to predict the behavior of these radioactive aerosols in the reactor cooling system and in the containment building under severe accident conditions. Aerosols are designated as very small solid particles or liquid droplets suspended in a gas phase. The suspended solid or liquid particles typically have a range of sizes of 0.01 m to 20 m. Aerosol concentrations in reactor accident analyses are typically less than 100 g/m3 and usually less than 1 g/m3. When there are continuing sources of aerosol to the gas phase or when there are complicated processes involving engineered safety features, much more complicated size distributions develop. It is not uncommon for aerosols in reactor containments to have bimodal size distributions for at least some significant periods of time early during an accident. Salient features of aerosol physics under reactor accident conditions that will affect the nature of the aerosols are (1) the formation of aerosol particles, (2) growth of aerosol particles, (3) shape of aerosol particles. At KAERI, a fission product module has been developed to predict the behaviors of the radioactive materials in the reactor coolant system under severe accident conditions. The fission product module consists of an estimation of the initial inventories, species release from the core, aerosol generation, gas transport, and aerosol transport. The final outcomes of the fission product module designate the radioactive gas and aerosol distribution in the reactor coolant system. The aerosol sedimentation models in the fission product module were validated using ABCOVE and LACE experiments. There were some discrepancies on the predicted

Fission product and aerosol behaviour within the containment

International Nuclear Information System (INIS)

Beard, A.M.; Benson, C.G.; Bowsher, B.R.; Dickinson, S.; Nichols, A.L.

1990-04-01

Experimental studies have been undertaken to characterise the behaviour of fission products in the containment of a pressurised water reactor during a severe accident. The following aspects of fission product transport have been studied: (a) aerosol nucleation, (b) vapour transport processes, (c) chemical forms of high-temperature vapours, (d) interaction of fission product vapours with aerosols generated from within the reactor core, (e) resuspension processes, (f) chemistry in the containment. Chemical effects have been shown to be important in defining and quantifying fission product source terms in a wide range of accident sequences. Both the chemical forms of the fission product vapours and their interactions with reactor materials aerosols could have a major effect on the magnitude and physicochemical forms of the radioactive emission from a severe reactor accident. Only the main conclusions are presented in this summary document; detailed technical aspects of the work are described in separate reports listed in the annex

Radioactive waste removing device

International Nuclear Information System (INIS)

Sakai, Takuhiko.

1982-01-01

Purpose: To cleanup primary coolants for LMFBR type reactors by magnetically generating a high speed rotational flow in the flow of liquid metal, and adsorbing radioactive corrosion products and fission products onto capturing material of a complicated shape. Constitution: Three-phase AC coils for generating a rotational magnetic field are provided to the outside of a container through which liquid sodium is passed to thereby generate a high speed rotational stream in the liquid sodium flowing into the container. A radioactive substance capturing material made of a metal plate such as of nickel and stainless steel in the corrugated shape with shape edges is secured within a flow channel. Magnetic field at a great slope is generated in the flow channel by the capturing material to adsorb radioactive corrosion products and fission products present in the liquid sodium onto the capturing material and removing therefrom. This enables to capture the ferri-magnetic impurities by adsorption. (Moriyama, K.)

Projectile fission of 238U relativistic ions in a Pb target and discovery of new fission fragments

International Nuclear Information System (INIS)

Bernas, M.; Donzaud, C.; Dessagne, Ph.; Miehe, Ch.; Hanelt, E.; Heinz, A.

1994-01-01

With the 238 U beam accelerated at relativistic energies by the heavy ion synchrotron (SIS) at GSI, fission was investigated using inverse kinematics. This geometry is well suited for analyzing fragments with the fragment separator. The fragments are identified by in flight measurements of their energy loss and time of flight signals. More than forty new isotopes have been discovered focusing on the light branch of fission products. (K.A.) 12 refs., 5 figs., 1 tab

Materials science and biophysics applications at the ISOLDE radioactive ion beam facility

Energy Technology Data Exchange (ETDEWEB)

Wahl, U., E-mail: uwahl@itn.pt [Instituto Tecnologico e Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Centro de Fisica Nuclear da Universidade de Lisboa, Av. Prof. Gama Pinto 2, 1649-003 Lisboa (Portugal)

2011-12-15

The ISOLDE isotope separator facility at CERN provides a variety of radioactive ion beams, currently more than 800 different isotopes from {approx}70 chemical elements. The radioisotopes are produced on-line by nuclear reactions from a 1.4 GeV proton beam with various types of targets, outdiffusion of the reaction products and, if possible, chemically selective ionisation, followed by 60 kV acceleration and mass separation. While ISOLDE is mainly used for nuclear and atomic physics studies, applications in materials science and biophysics account for a significant part (currently {approx}15%) of the delivered beam time, requested by 18 different experiments. The ISOLDE materials science and biophysics community currently consists of {approx}80 scientists from more than 40 participating institutes and 21 countries. In the field of materials science, investigations focus on the study of semiconductors and oxides, with the recent additions of nanoparticles and metals, while the biophysics studies address the toxicity of metal ions in biological systems. The characterisation methods used are typical radioactive probe techniques such as Moessbauer spectroscopy, perturbed angular correlation, emission channeling, and tracer diffusion studies. In addition to these 'classic' methods of nuclear solid state physics, also standard semiconductor analysis techniques such as photoluminescence or deep level transient spectroscopy profit from the application of radioactive isotopes, which helps them to overcome their chemical 'blindness' since the nuclear half life of radioisotopes provides a signal that changes in time with characteristic exponential decay or saturation curves. In this presentation an overview will be given on the recent research activities in materials science and biophysics at ISOLDE, presenting some of the highlights during the last five years, together with a short outlook on the new developments under way.

Imprints left by natural radioactivity in geological materials: uranium fission tracks and thermoluminescence applications in earth sciences

International Nuclear Information System (INIS)

Broquet, P.; Chambaudet, A.; Rebetez, M.; Charlet, J.M.

1994-01-01

In a rock, all minerals which contain uranium are host to a number of spontaneous fission phenomena forming a single damaged area called a ''latent track'', observations of which may lead to dating, uranium mapping and finding paleo-geo-thermometers (thermal history, used in oil exploration). The radioactive elements during the decay process release energy which is trapped as electrons into the physical or chemical defects of the crystalline lattice; this energy can be later released by heating the mineral (thermic stimulated luminescence); the thermoluminescence is characterized by a glow which spectrum constitutes a typical feature of the mineral, its crystallization conditions and the subsequent evolution of the material. Natural and induced glow curve may be produced. 6 figs., 52 refs

The Radioactive Ion Beams in Brazil (RIBRAS) facility. Description, program, main results, future plans

Energy Technology Data Exchange (ETDEWEB)

Lepine-Szily, A.; Lichtenthaeler, R.; Guimaraes, V. [Instituto de Fisica, Universidade de Sao Paulo (Brazil)

2014-08-15

RIBRAS (Radioactive Ion Beams in Brazil) is a facility installed at the Institute of Physics of the University of Sao Paulo (IFUSP), Brazil. The RIBRAS system consists of two superconducting solenoids and uses the ''in-flight method'' to produce radioactive ion beams using the primary beam provided by the 8UD Pelletron Tandem of IFUSP. The ion beams produced so far by RIBRAS are {sup 6}He, {sup 8}Li, {sup 7}Be, {sup 10}Be, {sup 8}B, {sup 12}B with intensities that can vary from 10{sup 4} to 10{sup 6} pps. Initially the experimental program covered the study of elastic and inelastic scattering with the objective to study the interaction potential and the reaction mechanisms between weakly bound (RIB) and halo ({sup 6}He and {sup 8}B) projectiles on light, medium and heavy mass targets. With highly purified beams, the study of resonant elastic scattering and resonant transfer reactions, using inverse kinematics and thick targets, has also been included in our experimental program. Also, transfer reactions of astrophysical interest and fusion reactions induced by halo nuclei are part of the near-future research program. Our recent results on elastic scattering, alpha-particle production and total reaction cross sections, as well as the resonant elastic and transfer reactions, are presented. Our plans for the near future are related to the installation of a new beam line and a cave for gamma-ray detection. We intend to place in operation a large area neutron detector available in our laboratory. The long-range plans could be the move of the RIBRAS system to the more energetic beam line of the LINAC post-accelerator (10MeV/nucleon primary beams) still in construction in our laboratory. (orig.)

Fast and slow radioactive beams in study of light nuclei far from stability

International Nuclear Information System (INIS)

Lewitowicz, M.

2003-01-01

Several examples of results of recent experiments performed with the SPIRAL ISOL-type and GANIL high energy radioactive beams on the properties of nuclei far from stability are presented. Future plans of the GANIL/SPIRAL facility related to the SPIRAL II project are shortly discussed. (orig.)

The SPES project of INFN: Facility and detectors

Directory of Open Access Journals (Sweden)

de Angelis G.

2015-01-01

Full Text Available The SPES Radioactive Ion Beam facility at INFN-LNL is presently in the construction phase. The facility is based on the Isol (Isotope separation on-line method with an UCx Direct Target able to sustain a power of 10 kW. The primary proton beam is provided by a high current Cyclotron accelerator with energy of 35-70 MeV and a beam current of 0.2-0.5 mA. Neutron-rich radioactive ions are produced by proton induced Uranium fission at an expected fission rate of the order of 1013 fissions per second. After ionization and selection the exotic isotopes are re-accelerated by the ALPI superconducting Linac at energies of 10A MeV for masses in the region A = 130 amu. The expected secondary beam rates are of the order of 107 - 109 pps. Aim of the SPES project is to provide a facility for high intensity radioactive ion beams for nuclear physics research as well as to develop an interdisciplinary research center based on the cyclotron proton beam.

Multi-Sampling Ionization Chamber (MUSIC) for measurements of fusion reactions with radioactive beams

International Nuclear Information System (INIS)

Carnelli, P.F.F.; Almaraz-Calderon, S.; Rehm, K.E.; Albers, M.; Alcorta, M.; Bertone, P.F.; Digiovine, B.; Esbensen, H.; Fernández Niello, J.; Henderson, D.; Jiang, C.L.; Lai, J.; Marley, S.T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R.C.; Paul, M.; Ugalde, C.

2015-01-01

A detection technique for high-efficiency measurements of fusion reactions with low-intensity radioactive beams was developed. The technique is based on a Multi-Sampling Ionization Chamber (MUSIC) operating as an active target and detection system, where the ionization gas acts as both target and counting gas. In this way, we can sample an excitation function in an energy range determined by the gas pressure, without changing the beam energy. The detector provides internal normalization to the incident beam and drastically reduces the measuring time. In a first experiment we tested the performance of the technique by measuring the 10,13,15 C+ 12 C fusion reactions at energies around the Coulomb barrier

Multi-Sampling Ionization Chamber (MUSIC) for measurements of fusion reactions with radioactive beams

Energy Technology Data Exchange (ETDEWEB)

Carnelli, P.F.F. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Laboratorio TANDAR, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, B1650KNA, San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917, C1033AAJ Buenos Aires (Argentina); Almaraz-Calderon, S. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Rehm, K.E., E-mail: rehm@anl.gov [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Albers, M.; Alcorta, M.; Bertone, P.F.; Digiovine, B.; Esbensen, H. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Fernández Niello, J. [Laboratorio TANDAR, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, B1650KNA, San Martín, Buenos Aires (Argentina); Universidad Nacional de San Martín, Campus Miguelete, B1650BWA San Martín, Buenos Aires (Argentina); Henderson, D.; Jiang, C.L. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Lai, J. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Marley, S.T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R.C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem (Israel); Ugalde, C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

2015-11-01

A detection technique for high-efficiency measurements of fusion reactions with low-intensity radioactive beams was developed. The technique is based on a Multi-Sampling Ionization Chamber (MUSIC) operating as an active target and detection system, where the ionization gas acts as both target and counting gas. In this way, we can sample an excitation function in an energy range determined by the gas pressure, without changing the beam energy. The detector provides internal normalization to the incident beam and drastically reduces the measuring time. In a first experiment we tested the performance of the technique by measuring the {sup 10,13,15}C+{sup 12}C fusion reactions at energies around the Coulomb barrier.

Radioactive substance separation systems

International Nuclear Information System (INIS)

Sakai, Takuhiko.

1981-01-01

Purpose: To enable separation of fission products, radioactive corrosion products and the likes in primary coolants with no requirement for the replacement of separation system during plant service life, by providing protruded magnetic pole plates in a liquid metal flow channel to thereby form slopes magnetic fields. Constitution: A plurality of magnetic pole plates are disposed vertically in a comb-like arrangement so as not to contact with each other along the direction of flow in a rectangular primary coolant pipeway at the exit of the reactor core in an LMFBR type reactor. Large magnetic poles are provided to the upper and lower sides of the pipeway and coils are wound on the side opposed to the pipeway. When electrical current is supplied to the coils, the magnetic pole is magnetized intensely and thus the magnetic pole plates are also magnetized intensely and thus the magnetic pole plates are also magnetized intensely to form large gradient in the magnetic fields between the upper and lower magnetic plates, whereby ferromagnetic and ferrimagnetic fission products and radioactive corrosion products in the coolants are intensely adsorbed and not detached by the flow of the coolants. Accordingly, the fission products and the radioactive corrosion products can surely be removed with no requirement for the exchange of separation system during plant service life. (Horiuchi, T.)

Study of chemically synthesized ZnO nano particles under a bio template using radioactive ion beam

CERN Multimedia

This is a project proposal to study nano sized semiconductor ZnO system, useful in biology and medicinal purposes, using radioactive ion beam from ISOLDE. Doping of the nano particles with Cu, Cd and Ga ions (in their variable valancy states) are expected to impart changes in the electrical structure and properties in the said system under study. The morphological changes, chemical environment, micro structure, electrical and optical properties of the nano size particles of ZnO system (developed under a bio template of folic acid) after the interaction with radioactive ion beam will be studied. The provision of perturbed angular correlation (PAC) study with respect to the changes in chemical environment, where ever possible will be attempted.

Production of fast neutrons from deuteron beams in view of producing radioactive heavy ions beams; Etude de la production de neutrons rapides a partir de faisceaux de deutons en vue de la mise en oeuvre de faisceaux d'ions lourds radioactifs

Energy Technology Data Exchange (ETDEWEB)

Pauwels, N

2000-11-01

This thesis is part of two research and development programmes for the study of neutron rich radioactive nuclear beam production. The technique is based on the ISOL method and can be summarized as follows. Fast neutrons are generated by the break-up of deuterons in a thick target. These neutrons irradiate a fissionable {sup 238}U target. The resulting fission products are extracted from the target, ionised, mass selected and post-accelerated. The aim of the thesis is to study the neutron angular and energetic distributions. After a bibliographical research to justify the choice of deuterons as the best projectile, we developed more specifically three points: - the extension of the activation detector method for neutron spectroscopy to a wide energy range (1 to 150 MeV), - the experimental measurement of neutron angular and energetic distributions produced by deuterons on thick targets. The deuteron energy ranges from 17 to 200 MeV and the thick targets were Be, C and U, - the realization of a code based on Serber's theory to predict the neutron distribution for any couple (deuteron energy-thick target). We conclude that for our application the most suitable target is C and the best deuteron energy is about 100 MeV. (author)

Development of a radioactive ion beam test stand at LBNL

International Nuclear Information System (INIS)

Burke, J.; Freedman, S.J.; Fujikawa, B.; Gough, R.A.; Lyneis, C.M.; Vetter, P.; Wutte, D.; Xie, Z.Q.

1998-01-01

For the on-line production of a 14 O + ion beam, an integrated target--transfer line ion source system is now under development at LBNL. 14 O is produced in the form of CO in a high temperature carbon target using a 20 MeV 3 He beam from the LBNL 88'' Cyclotron via the reaction 12 C( 3 He,n) 14 O. The neutral radioactive CO molecules diffuse through an 8 m room temperature stainless steel line from the target chamber into a cusp ion source. The molecules are dissociated, ionized and extracted at energies of 20 to 30 keV and mass separated with a double focusing bending magnet. The different components of the setup are described. The release and transport efficiency for the CO molecules from the target through the transfer line was measured for various target temperatures. The ion beam transport efficiencies and the off-line ion source efficiencies for Ar, O 2 and CO are presented. Ionization efficiencies of 28% for Ar + , 1% for CO, 0.7% for O + , 0.33 for C + have been measured

Review of fission-fusion pellet designs and inertial confinement system studies at EIR

Energy Technology Data Exchange (ETDEWEB)

Seifriz, W [Eidgenoessisches Inst. fuer Reaktorforschung, Wuerenlingen (Switzerland)

1978-01-01

The article summarizes the work done so far at the Swiss Federal Institute for Reactor Research (EIR) in the field of the inertial confinement fusion technique. The following subjects are reviewed: a) fission fusion pellet designs using fissionable triggers, b) uranium tampered pellets, c) tampered pellets recycling unwanted actinide wastes from fission reactors in beam-driven micro-explosion reactors, and d) symbiotic fusion/fission reactor studies.

A linear radiofrequency ion trap for accumulation, bunching, and emittance improvement of radioactive ion beams

International Nuclear Information System (INIS)

Herfurth, F.; Dilling, J.; Kellerbauer, A.

2000-05-01

An ion beam cooler and buncher has been developed for the manipulation of radioactive ion beams. The gas-filled linear radiofrequency ion trap system is installed at the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. Its purpose is to accumulate the 60-keV continuous ISOLDE ion beam with high efficiency and to convert it into low-energy low-emittance ion pulses. The efficiency was found to exceed 10% in agreement with simulations. A more than 10-fold reduction of the ISOLDE beam emittance can be achieved. The system has been used successfully for first on-line experiments. Its principle, setup and performance will be discussed. (orig.)

Fission barriers in the quasi-molecular shape path

International Nuclear Information System (INIS)

Royer, G.; Bonilla, C.; Zbiri, K.; Gherghescu, R.A.

2003-01-01

New observed phenomena like asymmetric fission of intermediate mass nuclei, nuclear molecules in light nuclei, super and hyperdeformations, cluster radioactivity, fast-fission of heavy systems and fragmentation have renewed interest in investigating the fusion-like fission valley which leads rapidly to two touching spherical fragments and quasi-molecular shapes. Furthermore, rotating super and hyperdeformed nuclear states and superheavy nuclei can be formed only in heavy-ion collisions for which the initial configuration is two close quasi-spherical nuclei. For these shapes the balance between the Coulomb forces and surface tension forces does not allow to link the sheets of the potential energy surface corresponding to one-body shapes and to two separated fragments, respectively. It is necessary to add another term called proximity energy reproducing the finite-range effects of the nuclear force in the neck or the gap between the nascent fission fragments. A generalized liquid drop model has been developed to take into account this nuclear proximity energy, the mass and charge asymmetry, an accurate nuclear radius and the temperature effects. The initial value of the surface energy coefficient has been kept. Microscopic corrections have been determined within the asymmetric two center shell model or simpler algebraic approximations. With this model and deformation valley first studies had led to the following results: (i) good agreement between the potential barrier heights and the experimental fission barrier heights in the whole mass range; (ii) saddle-point corresponding to two separated fragments maintained in unstable equilibrium by the balance between the repulsive Coulomb forces and the attractive proximity forces; (iii) strong enhancement of the maximal angular momentum against fission; (iv) reasonable agreement with experimental data on the double-humped barriers of actinides. Within this same approach we have recently shown that the calculated potential

K isomerism and collectivity in neutron-rich rare-earth isotopes.

OpenAIRE

Patel, Zena

2016-01-01

Neutron-rich rare-earth isotopes were produced by in-flight fission of 238U ions at the Radioactive Isotope Beam Factory (RIBF), RIKEN, Japan. In-flight fission of a heavy, high-intensity beam of 238U ions on a light target provides the cleanest secondary beams of neutron-rich nuclei in the rare-earth region of isotopes. In-flight fission is advantageous over other methods of nuclear production, as it allows for a secondary beam to be extracted, from which the beam species can be separated an...

Chernobyl radioactivity and high altitude air-particulate monitoring at Islamabad

International Nuclear Information System (INIS)

Bhatti, M.S.; Ihsanullah; Shafiq, M.; Perveen, N.; Orfi, S.D.

1987-11-01

High altitude sampling of air particulates for radioactivity monitoring was conducted at Islamabad after the CHERNOBYL accident. Smears from aeroplanes flying at varying altitudes were collected and analysed for fresh fission products mainly gamma emitters e.g. Ru-103 and Cs-137 etc. The maximum radioactivity observed was of the order of 15Bq/sample for Ru-103 and 9Bq/sample for Cs-137 respectively. The study was purely qualitative in nature indicated the presence of fresh fission radioactivity at high altitudes over Islamabad. For quantitative measurements at high altitudes sophisticated instrumentation/procedure needs to be adopted. (author)

Project 'Installation of a stand at the horizontal channel of the MARIA Research Reactor, Otwock-Swierk, Poland, for the research of transmutation of minor actinides and fission products'

International Nuclear Information System (INIS)

Szuta, M.

2006-01-01

As a long range objective we would like to focus on management of the fuel economy in the sub-critical assembly of the accelerator driven system (ADS) in terms of long lived fission products (LLFP) and minor actinides (MA) transmutation. Transmutation of the radioactive waste (RW) is an important element within the technical objective of the optimal management of the fuel economy in the sub-critical assembly of the accelerator driven system (ADS). Analysis of possible ways of reduction of radioactive wastes by transmutation of radioactive long-lived fission products such as 99 Tc, 129 I and 135 Cs and by burning up of transuranic nuclides implies that the sub-critical assembly of the accelerator driven system should consist of three zones. The requirement of three zones comes out of the fact that each radioactive isotope to be reduced is to be located in a different spectrum of thermal, epithermal and high energy neutron fluxes. High flux thermal neutron environment (≥10 16 n/cm 3 ·s) is expected as the best way for the transmutation of most of the radioactive waste to stable or short-lived nuclides and for increasing the probability for fission such actinides as 237 Np and 238 Np. The concept of ADS system for energy production and for transmutation is quite new to some extent and from this reason it requires many theoretical and experimental studies. The research of transmutation is a very large area of study requiring a significant experimental and financial support, so it can be performed only within the international cooperation. Specifically, the proposed research within this CRP requires important means, in terms of high-energy proton beams, spallation targets, sub-critical assembly, measurement instrumentation, post-irradiation characterisation and its testing and, of course, manpower for the interpretation of results, modelling observed phenomena, and programme management. The personal involved in the research is to be a skilled personal of

Potential and limitations of nucleon transfer experiments with radioactive beams at REX-ISOLDE

CERN Document Server

Gund, C.; Cub, J.; Dietrich, A.; Hartlein, T.; Lenske, H.; Pansegrau, D.; Richter, A.; Scheit, H.; Schrieder, G.; Schwalm, D.

2001-01-01

As a tool for studying the structure of nuclei far off stability the technique of $\\gamma$-ray spectroscopy after low-energy single-nucleon transfer reactions with radioactive nuclear beams in inverse kinematics was investigated. Modules of the MINIBALL germanium array and a thin position-sensitive parallel plate avalanche counter (PPAC) to be employed in future experiments at REX-ISOLDE were used in a test experiment performed with a stable $^{36}$S beam on deuteron and $^{9}$Be targets. It is demonstrated that the Doppler broadening of $\\gamma$ lines detected by the MINIBALL modules is considerably reduced by exploiting their segmentation, and that for beam intensities up to 10$^{6}$ particles/s the PPAC positioned around zero degrees with respect to the beam axis allows not only to significantly reduce the gamma background by requiring coincidences with the transfer products but also to control the beam and its intensity by single particle counting. The predicted large neutron pickup cross-sections of neut...

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.

On the safety of conceptual fusion-fission hybrid reactors

International Nuclear Information System (INIS)

Kastenberg, W.E.; Okrent, D.; Badham, V.; Caspi, S.; Chan, C.K.; Ferrell, W.J.; Frederking, T.H.K.; Grzesik, J.; Lee, J.Y.; McKone, T.E.; Pomraning, G.C.; Ullman, A.Z.; Ting, T.D.; Kim, Y.I.

1979-01-01

A preliminary examination of some potential safety questions for conceptual fusion-fission hybrid reactors is presented in this paper. The study and subsequent analysis was largely based upon one design, a conceptual mirror fusion-fission reactor, operating on the deuterium-tritium plasma fusion fuel cycle and the uranium-plutonium fission fuel cycle. The major potential hazards were found to be: (a) fission products, (b) actinide elements, (c) induced radioactivity, and (d) tritium. As a result of these studies, it appears that highly reliable and even redundent decay heat removal must be provided. Loss of the ability to remove decay heat results in melting of fuel, with ultimate release of fission products and actinides to the containment. In addition, the studies indicate that blankets can be designed which will remain subcritical under extensive changes in both composition and geometry. Magnet safety and the effects of magnetic fields on thermal parameters were also considered. (Auth.)

Prospects for studies of ground-state proton decays with the Holifield Radioactive Ion Beam Facility

International Nuclear Information System (INIS)

Toth, K.S.

1994-01-01

By using radioactive ions from the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory it should be possible to identify many new ground-state proton emitters in the mass region from Sn to Pb. During this production and search process the limits of stability on the proton-rich side of the nuclidic chart will be delineated for a significant fraction of medium-weight elements and our understanding of the proton-emission process will be expanded and improved

Resonant ionization by laser beams: application to ions sources and to study the nuclear structure of radioactive tellurium isotopes

International Nuclear Information System (INIS)

Sifi, R.

2007-07-01

The radioactive ion beams that are produced through current isotope separators are well separated according to the A mass but not according to the Z parameter. The resonant ionization through laser beams applied to ion sources allows the production of radioactive ion beam in a very selective and efficient way by eliminating the isobaric contamination. The first chapter is dedicated to the resonant ionization by laser beams, we describe the principle, the experimental setting, the lasers used, the ionization schemes and the domain of application. The second chapter deals with the application of resonant ionization to laser ion sources for the production of radioactive ion beams. We present experimental tests performed for getting copper ion beams. Resonant ionization through laser is also used in the spectroscopy experiments performed at the Isolde (isotope separation on-line device) installation in CERN where more than 20 elements are ionized very efficiently. The technique is based on a frequency scanning around the excitation transition of the atoms in order to probe the hyperfine structure. Laser spectroscopy allows the determination of the hyperfine structure as well as the isotopic shift of atoms. In the third chapter the method is applied to the spectroscopy of tellurium atoms. First, we define the 2 parameters on which the extraction is based: charge radius and nuclear moments, then we present several theoretical models that we have used to assess our experimental results. (A.C.)

Modelling and simulation the radioactive source-term of fission products in PWR type reactors

International Nuclear Information System (INIS)

Porfirio, Rogilson Nazare da Silva

1996-01-01

The source-term was defined with the purpose the quantify all radioactive nuclides released the nuclear reactor in the case of accidents. Nowadays the source-term is limited to the coolant of the primary circuit of reactors and may be measured or modelled with computer coders such as the TFP developed in this work. The calculational process is based on the linear chain techniques used in the CINDER-2 code. The TFP code considers forms of fission products release from the fuel pellet: Recoil, Knockout and Migration. The release from the gap to the coolant fluid is determined from the ratio between activity measured in the coolant and calculated activity in the gap. Considered the operational data of SURRY-1 reactor, the TFP code was run to obtain the source=term of this reactor. From the measured activities it was verified the reliability level of the model and the employed computational logic. The accuracy of the calculated quantities were compared to the measured data was considered satisfactory. (author)

Fission fragment yields from heavy-ion-induced reactions measured with a fragment separator

Science.gov (United States)

Tarasov, O. B.; Delaune, O.; Farget, F.; Morrissey, D. J.; Amthor, A. M.; Bastin, B.; Bazin, D.; Blank, B.; Cacéres, L.; Chbihi, A.; Fernández-Dominguez, B.; Grévy, S.; Kamalou, O.; Lukyanov, S. M.; Mittig, W.; Pereira, J.; Perrot, L.; Saint-Laurent, M.-G.; Savajols, H.; Sherrill, B. M.; Stodel, C.; Thomas, J. C.; Villari, A. C.

2018-04-01

The systematic study of fission fragment yields under different initial conditions has provided valuable experimental data for benchmarking models of fission product yields. Nuclear reactions using inverse kinematics coupled to the use of a high-resolution spectrometer with good fragment identification are shown here to be a powerful tool to measure the inclusive isotopic yields of fission fragments. In-flight fusion-fission was used in this work to produce secondary beams of neutron-rich isotopes in the collisions of a 238U beam at 24 MeV/u with 9Be and 12C targets at GANIL using the LISE3 fragment separator. Unique identification of the A, Z, and atomic charge state, q, of fission products was attained with the Δ E- TKE-B ρ- ToF measurement technique. Mass, and atomic number distributions are reported for the two reactions. The results show the importance of different reaction mechanisms in the two cases. The optimal target material for higher yields of neutron-rich high- Z isotopes produced in fusion-fission reactions as a function of projectile energy is discussed.

Titanium carbide-carbon porous nanocomposite materials for radioactive ion beam production: processing, sintering and isotope release properties

CERN Document Server

AUTHOR|(CDS)2081922; Stora, Thierry

2017-01-26

The Isotope Separator OnLine (ISOL) technique is used at the ISOLDE - Isotope Separator OnLine DEvice facility at CERN, to produce radioactive ion beams for physics research. At CERN protons are accelerated to 1.4 GeV and made to collide with one of two targets located at ISOLDE facility. When the protons collide with the target material, nuclear reactions produce isotopes which are thermalized in the bulk of the target material grains. During irradiation the target is kept at high temperatures (up to 2300 °C) to promote diffusion and effusion of the produced isotopes into an ion source, to produce a radioactive ion beam. Ti-foils targets are currently used at ISOLDE to deliver beams of K, Ca and Sc, however they are operated at temperatures close to their melting point which brings target degradation, through sintering and/or melting which reduces the beam intensities over time. For the past 10 years, nanostructured target materials have been developed and have shown improved release rates of the produced i...

Simulation of Fission Product Liftoff Behavior During Depressurization Transients

International Nuclear Information System (INIS)

Tak, Nam-il; Yoon, Churl; Lee, Sung Nam

2016-01-01

As one of crucial technologies for the NHDD project, the development of the GAMMA-FP code is on-going. The GAMMA-FP code is targeted for fission product transport analysis under accident conditions. A well-known experiment named COMEDIE considered two important phenomena, i.e., fission product plateout and liftoff, for fission product transport within the primary circuit of a prismatic high temperature gas cooled reactor. The accumulated fission products on the structural material via the plateout can be liftoff during a blowdown phase after a pipe break accident. Since the fission product liftoff can increase a radioactivity risk, it is important to predict the amount of fission product liftoff during depressurization accidents. In this work, a model for fission product liftoff is implemented into the GAMMA-FP code and the GAMMA-FP code with the implemented model is validated using the COMEDIE blowdown test data. The results of GAMMA-FP show that the GAMMA-FP code can reliably simulate a pressure transient during blowdown phase after a pipe break accident. In addition, a reasonable amount of fission product liftoff was predicted by the GAMMA-FP code. The maximum difference between the measured and predicted liftoff fraction was less than a factor of 10. More in-depth study is required to increase the accuracy of prediction for a fission product liftoff

Fission fragment angular distribution in the reaction 28Si+176Yb

International Nuclear Information System (INIS)

Tripathi, R.; Sudarshan, K.; Sharma, S.K.; Reddy, A.V.R.; Pujari, P.K.; Dutta, D.; Goswami, A.; Ramachandran, K.

2009-01-01

Fission fragment angular distribution has been measured in the reaction 28 Si+ 176 Yb at beam energies of 145 and 155 MeV to investigate the contribution from non-compound nucleus fission. Experiments were carried out at BARC-TIFR Pelletron-LINAC accelerator facility, Mumbai. Experimental angular anisotropies in this reaction were observed to be higher than those calculated using statistical theory, indicating contribution from non-compound nucleus fission in this reaction. (author)

Fusion-fission hybrids: environmental aspects and their role in hybrid rationale

International Nuclear Information System (INIS)

Holdren, J.P.

1981-01-01

The rationale for developing hybrids depends on real or perceived liabilities of relying on pure fission to do the same job. Quite possibly the main constraint on expanded use of fission will be neither lack of fuel nor high costs, but perceived environmental liabilities - radioactive wastes, reactor safety, and links to nuclear weaponry. The environmental characteristics of hybrid systems and pure-fisson systems are compared here in detail. The findings are that significant environmental advantages for hybrids cannot now be demonstrated and may not exist. Therefore, if environmental drawbacks constrain the application of pure fission, hybrids probably also will be thus constrained

Fission Product Yield Study of 235U, 238U and 239Pu Using Dual-Fission Ionization Chambers

Science.gov (United States)

Bhatia, C.; Fallin, B.; Howell, C.; Tornow, W.; Gooden, M.; Kelley, J.; Arnold, C.; Bond, E.; Bredeweg, T.; Fowler, M.; Moody, W.; Rundberg, R.; Rusev, G.; Vieira, D.; Wilhelmy, J.; Becker, J.; Macri, R.; Ryan, C.; Sheets, S.; Stoyer, M.; Tonchev, A.

2014-05-01

To resolve long-standing differences between LANL and LLNL regarding the correct fission basis for analysis of nuclear test data [M.B. Chadwick et al., Nucl. Data Sheets 111, 2891 (2010); H. Selby et al., Nucl. Data Sheets 111, 2891 (2010)], a collaboration between TUNL/LANL/LLNL has been established to perform high-precision measurements of neutron induced fission product yields. The main goal is to make a definitive statement about the energy dependence of the fission yields to an accuracy better than 2-3% between 1 and 15 MeV, where experimental data are very scarce. At TUNL, we have completed the design, fabrication and testing of three dual-fission chambers dedicated to 235U, 238U, and 239Pu. The dual-fission chambers were used to make measurements of the fission product activity relative to the total fission rate, as well as for high-precision absolute fission yield measurements. The activation method was employed, utilizing the mono-energetic neutron beams available at TUNL. Neutrons of 4.6, 9.0, and 14.5 MeV were produced via the 2H(d,n)3He reaction, and for neutrons at 14.8 MeV, the 3H(d,n)4He reaction was used. After activation, the induced γ-ray activity of the fission products was measured for two months using high-resolution HPGe detectors in a low-background environment. Results for the yield of seven fission fragments of 235U, 238U, and 239Pu and a comparison to available data at other energies are reported. For the first time results are available for neutron energies between 2 and 14 MeV.

Reduction of radioactivity produced by nuclear explosives

Energy Technology Data Exchange (ETDEWEB)

Lessler, Richard M [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-15

Four main sources contribute to the radioactivity produced by a nuclear explosive: 1. Fission products from the nuclear explosive, 2. Fusion products from the nuclear explosive, 3. Induced radioactivity in the nuclear explosive, 4. Induced radioactivity in the environment. This paper will summarize some of the work done at the Lawrence Radiation Laboratory at Livermore to reduce the radioactivity from these sources to levels acceptable for peaceful applications. Although it is theoretically possible to have no radioactivity produced by nuclear explosives, this goal has not been achieved.

''In situ'' investigations of the radioactive fissionable element infiltration and retention in different soils

International Nuclear Information System (INIS)

Oncescu, M.; Danis, A.; Sahagia, M.; Negrescu, C.; Bobe, M.; Balanescu, P.; Burcescu, M.; Tautu, N.

1980-01-01

''In situ'' investigations of the natural and forced infiltration and retention of the fissionable elements from a liquid residue in several natural compacted soils and compacted clays are presented. The velocities and flow rates for different stages of the residue infiltration are determined. The retention of the fissionable elements by variation of the fissionable element concentration with the distance from the place of the residue depot is investigated. (author)

Charge breeding of radioactive isotopes at the CARIBU facility with an electron beam ion source

Science.gov (United States)

Vondrasek, R. C.; Dickerson, C. A.; Hendricks, M.; Ostroumov, P.; Pardo, R.; Savard, G.; Scott, R.; Zinkann, G.

2018-05-01

An Electron Beam Ion Source Charge Breeder (EBIS-CB) has been developed at Argonne National Laboratory as part of the californium rare ion breeder upgrade. For the past year, the EBIS-CB has been undergoing commissioning as part of the ATLAS accelerator complex. It has delivered both stable and radioactive beams with A/Q 18% into a single charge state. The operation of this device, challenges during the commissioning phase, and future improvements will be discussed.

ANS-5.4 fission gas release model. I. Noble gases at high temperature

International Nuclear Information System (INIS)

Noble, L.D.

1979-01-01

A correlation to describe the release of volatile radioactive fission products has been developed by the ANS Working Group (ANS 5.4) on Fuel Plenum Activity. The model for release at higher temperatures is identical in form to conventional diffusion equations, but the effective diffusion coefficient incorporates an explicit dependence upon exposure. Because applicable radioactive release data is limited, parameters in the model were determined from stable fission measurements, and calculated or measured fuel temperatures. Although the model predicts high release, particularly at higher exposures, values for many cases of interest are considerably less than the 100% assumed in some accident analyses: providing potential for removal of unnecessary conservations

Gamma-Ray Spectroscopy at TRIUMF-ISAC: the New Frontier of Radioactive Ion Beam Research

Science.gov (United States)

Ball, G. C.; Andreoiu, C.; Austin, R. A. E.; Bandyopadhyay, D.; Becker, J. A.; Bricault, P.; Brown, N.; Chan, S.; Churchman, R.; Colosimo, S.; Coombes, H.; Cross, D.; Demand, G.; Drake, T. E.; Dombsky, M.; Ettenauer, S.; Finlay, P.; Furse, D.; Garnsworthy, A.; Garrett, P. E.; Green, K. L.; Grinyer, G. F.; Hyland, B.; Hackman, G.; Kanungo, R.; Kulp, W. D.; Lassen, J.; Leach, K. G.; Leslie, J. R.; Mattoon, C.; Melconian, D.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Rand, E.; Sarazin, F.; Svensson, C. E.; Sumithrarachchi, S.; Schumaker, M. A.; Triambak, S.; Waddington, J. C.; Walker, P. M.; Williams, S. J.; Wood, J. L.; Wong, J.; Zganjar, E. F.

2009-03-01

High-resolution gamma-ray spectroscopy is essential to fully exploit the unique scientific opportunities at the next generation radioactive ion beam facilities such as the TRIUMF Isotope Separator and Accelerator (ISAC). At ISAC the 8π spectrometer and its associated auxiliary detectors is optimize for β-decay studies while TIGRESS an array of segmented clover HPGe detectors has been designed for studies with accelerated beams. This paper gives a brief overview of these facilities and also presents recent examples of the diverse experimental program carried out at the 8π spectrometer.

Future prospects for radioactive nuclear beams in North America

International Nuclear Information System (INIS)

Nitschke, J.M.

1993-05-01

In 1989 this author proposed the construction of a dedicated, flexible, radioactive nuclear beams facility that would provide intense beams of nearly all elements for a program of scientific studies in nuclear structure, nuclear reaction dynamics, astrophysics, high-spin physics, nuclei far from stability, material- and surface science, and atomic- and hyperfine-interaction physics. The initial name proposed for the new facility was ''IsoSpin Factory'' to underscore the key feature of this new physics tool; it was later changed to ''IsoSpin Laboratory'' (ISL). The ISL is now supported by a broad base of nuclear scientists and has been identified in the US Long Range Plan on Nuclear Science as one of the new potential construction projects for the second part of this decade. Since 1989 a number of conferences and workshops has been held in which the scientific and technical case for RNB facilities has been made. The purpose of this paper is to focus on the North American plan for the ISL, which was initially summarized in a ''White Paper'' but has since evolved in its scientific and technical scop

General Description of Fission Observables - JEFF Report 24. GEF Model

International Nuclear Information System (INIS)

Schmidt, Karl-Heinz; Jurado, Beatriz; Amouroux, Charlotte

2014-06-01

The Joint Evaluated Fission and Fusion (JEFF) Project is a collaborative effort among the member countries of the OECD Nuclear Energy Agency (NEA) Data Bank to develop a reference nuclear data library. The JEFF library contains sets of evaluated nuclear data, mainly for fission and fusion applications; it contains a number of different data types, including neutron and proton interaction data, radioactive decay data, fission yield data and thermal scattering law data. The General fission (GEF) model is based on novel theoretical concepts and ideas developed to model low energy nuclear fission. The GEF code calculates fission-fragment yields and associated quantities (e.g. prompt neutron and gamma) for a large range of nuclei and excitation energy. This opens up the possibility of a qualitative step forward to improve further the JEFF fission yields sub-library. This report describes the GEF model which explains the complex appearance of fission observables by universal principles of theoretical models and considerations on the basis of fundamental laws of physics and mathematics. The approach reveals a high degree of regularity and provides a considerable insight into the physics of the fission process. Fission observables can be calculated with a precision that comply with the needs for applications in nuclear technology. The relevance of the approach for examining the consistency of experimental results and for evaluating nuclear data is demonstrated. (authors)

Utilization of fast reactor excess neutrons for burning long-lived fission products

International Nuclear Information System (INIS)

Kawashima, K.; Kobayashi, K.; Kaneto, K.

1995-01-01

An evaluation is made on a large MOX fuel fast reactor's capability of burning long lived fission product Tc-99, which dominates the long term radiotoxicity of the high level radioactive waste. The excess neutrons generated in the fast reactor core are utilized to transmute Tc-99 to stable isotopes due to neutron capture reaction. The fission product target assemblies which consist of Tc-99 are charged to the reactor core periphery. The fission product target neutrons are moderated to a great deal to pursue the possibility of enhancing the transmutation rate. Any impacts of loading the fission product target assemblies on the core nuclear performances are assessed. A long term Tc-99 accumulation scenario is considered in the mix of fission product burner fast reactor and non-burner LWRs. (author)

Analytic description of the fusion and fission processes through compact quasi-molecular shapes

International Nuclear Information System (INIS)

Royer, G.; Normand, C.; Druet, E.

1997-01-01

Recent studies have shown that the characteristics of the entrance and exit channels through compact quasi-molecular shapes are compatible with the experimental data on fusion, fission and cluster radioactivity when the deformation energy is determined within a generalized liquid drop model. Analytic expressions allowing to calculate rapidly the main characteristics of this deformation path through necked shapes with quasi-spherical ends are presented now; namely formulas for the fusion and fission barrier heights, the fusion barrier radius, the symmetric fission barriers and the proximity energy. (author)

Experiments on the nuclear fragmentation and on the production of radioactive beams for direct reactions

International Nuclear Information System (INIS)

Weiss, A.

1993-06-01

In April 1992 at the GSI a prototype experiment on the production and study of the double-magic radioactive nucleus 56 Ni was successfully performed with proton scattering in inverse kinematics. A 350 MeV/u 56 Ni primary beam from the heavy ion synchrotron SIS was fragmented in a 4/g/cm 2 thick beryllium target. The separation of the formed isotopes ensued in the fragment separator FRS, which was operated in the achromatic mode with a degrader. Production cross sections for a whole series of fragments in the range 29≥Z≥19 and 57≥A≥41 were obtained. It succeeded to detect proton-rich isotopes at the boundary of the stability as for instance 52 Co, 51 Co, 50 Co, or 52 Ni and to determine for the first time their production cross sections. A further part of this thesis with regard to experiments with radioactive beams were first test experiments at the experimental storage ring ESR. The spotlight held luminosity measurements at the internal gas target with cooled, stable proton beam. For this the elastic scattering was stuided in inverse kinematics in the Rutherford range. Studied were different projectile beams (Ne, Xe) at energies of 150 MeV/u respectively 250 MeV/u and gas jets of nitrogen, argon, and hydrogen. The measured energy spectra of the recoils are in agreement with simulation calculations

Background and derivation of ANS-5.4 standard fission product release model. Technical report

International Nuclear Information System (INIS)

1982-01-01

ANS Working Group 5.4 was established in 1974 to examine fission product releases from UO2 fuel. The scope of ANS-5.4 was narrowly defined to include the following: (1) Review available experimental data on release of volatile fission products from UO2 and mixed-oxide fuel; (2) Survey existing analytical models currently being applied to lightwater reactors; and (3) Develop a standard analytical model for volatile fission product release to the fuel rod void space. Place emphasis on obtaining a model for radioactive fission product releases to be used in assessing radiological consequences of postulated accidents

Microbial Transformations of Actinides and Fission Products in Radioactive Waste

Energy Technology Data Exchange (ETDEWEB)

Francis, A. J. [Pohang Univ. Science and Technology, Pohang (Korea, Republic of)

2011-07-01

The environmental factors that can affect microbial growth and activity include moisture, temperature, ph, Eh, availability of organic and inorganic nutrients, and radiation. The microbial activity in a specific repository is influenced by the ambient environment of the repository, and the materials to be emplaced. For example, a repository in unsaturated igneous rock formations such as volcanic tuff rocks at Yucca Mountain is generally expected to be oxidizing; a repository in a hydrologically expected to be oxidizing; a repository in a hydrologically saturated zone, especially in sedimentary rocks, could be reducing. Sedimentary rocks contain a certain amount of organic matter, which may stimulate microbial activities and, thus maintain the repository and its surrounding areas at reducing conditions. Although the impacts of microbial activity on high-level nuclear waste and the long-term performance of the repository have not fully investigated, little microbial activity is expected in the near-field because of the radiation, lack of nutrients and the harsh conditions. However in the far-field microbial effects could be significant. Much of our understanding of the microbial effects on radionuclides stems from studies conducted with selected transuranic elements and fission products and limited studies with low-level radioactive wastes. Significant aerobic- and anaerobic-microbial activity is expected to occur in the waste because of the presence of electron donors and acceptors. The actinides initially may be present as soluble- or insoluble-forms but, after disposal, may be converted from one to the other by microorganisms. The direct enzymatic or indirect non-enzymatic actions of microbes could alter the speciation, solubility, and sorption properties of the actinides, thereby increasing or decreasing their concentrations in solution.

Cold fission description with constant and varying mass asymmetries

International Nuclear Information System (INIS)

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

1998-01-01

Different description for varying the mass asymmetry in the fragmentation process are used to calculate the cold fission barrier penetrability. The relevance of the appropriate choice for both the description of the pre-scission phase and inertia coefficient to unify alpha decay, cluster radioactivity, and spontaneous cold fission processes in the same theoretical framework is explicitly shown. We calculate the half-life of all possible partition modes of nuclei of A > 200 following the most recent Mass Table by Audi and Wapstra. It is shown that if one uses the description in which the mass asymmetry is maintained constant during the fragmentation process, the experimental half-life-values and mass yield of 234 U cold fission are satisfactorily reproduced. (author)

Accelerator-driven thermal fission systems may provide energy supply advantages

International Nuclear Information System (INIS)

Linford, R.K.

1992-01-01

This presentation discusses the energy supply advantages of using accelerator-driven thermal fission systems. Energy supply issues as related to cost, fuel supply stability, environmental impact, and safety are reviewed. It is concluded that the Los Alamos Accelerator Transmutation of Waste (ATW) concept, discussed here, has the following advantages: improved safety in the form of low inventory and subcriticality; reduced high-level radioactive waste management timescales for both fission products and actinides; and a very long-term fuel supply requiring no enrichment

A project for storing the radioactive sludges from Marcoule in the soil (1960); Une solution de stockage dans le sol des boues radioactives de Marcoule (1960)

Energy Technology Data Exchange (ETDEWEB)

Cohen, P; Gailledreau, C [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1960-07-01

A study of the feasibility of storing radioactive sludges in the soil. Special attention is paid to the case of the Marcoule plant, producing three kinds of sludges. The movement of the different fission products is given. (author) [French] Etude de la possibilite de stocker dans le sol des boues radioactives. Le cas de la station de traitement des effluents de Marcoule, produisant trois types de boues, est etudie plus specialement. Le mouvement des divers produits de fission est precise. (auteur)

Radioactive Waste Issues related to Production of Fission-based Mo-99 by using Low Enriched Uranium (LEU)

Energy Technology Data Exchange (ETDEWEB)

Hassan, Muhmood ul; Ryu, Ho Jin [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

2014-10-15

In order to produce fission-based Mo-99 from research reactors, two types of targets are being used and they are highly enriched uranium (HEU) targets with {sup 235}U enrichment more than 90wt% of {sup 235}U and low enriched uranium (LEU) targets with {sup 235}U enrichment less than 20wt% of {sup 235}U. It is worth noting that medium enriched uranium i.e. 36wt% of {sup 235}U as being used in South Africa is also regarded as non-LEU from a nuclear security point of view. In order to cope with the proliferation issues, international nuclear security policy is promoting the use of LEU targets in order to minimize the civilian use of HEU. It is noteworthy that Mo-99 yield of the LEU target is less than 20% of the HEU target, which requires approximately five times more LEU targets to be irradiated and consequently results in increased volume of waste. The waste generated from fission Mo-99 production can be mainly due to: target fabrication, assembling of target, irradiation in reactor and processing of irradiated targets. During the fission of U-235 in a reactor, a large number of radionuclides with different chemical and physical properties are formed. The waste produced from these practices may be a combination of low level waste (LLW) and intermediate level waste (ILW) comprised of all three types, i.e., solid, liquid and gas. Handling and treatment of the generated waste are dependent on its form and activity. In case of the large production facility, waste storage facility should be constructed in order to limit the radiation exposures of the workers and the environment. In this study, we discuss and compare mainly the radioactive waste generated by alkaline digestion of both HEU and LEU targets to assist in planning and deciding the choice of the technology with better arrangements for proper handling and disposal of generated waste. With the use of the LEU targets in Mo-99 production facility, significant increase in liquid and solid waste has been expected.

Measurements of Short-Lived Fission Isomers

Science.gov (United States)

Finch, Sean; Bhike, Megha; Howell, Calvin; Krishichayan, Fnu; Tornow, Werner

2016-09-01

Fission yields of the short lived isomers 134mTe (T1 / 2 = 162 ns) and 136mXe (T1 / 2 = 2 . 95 μs) were measured for 235U and 238U. The isomers were detected by the γ rays associated with the decay of the isomeric states using high-purity germanium detectors. Fission was induced using both monoenergetic γ rays and neutrons. At TUNL's High-Intensity Gamma-ray Source (HI γS), γ rays of 9 and 11 MeV were produced . Monoenergetic 8 MeV neutrons were produced at TUNL's tandem accelerator laboratory. Both beams were pulsed to allow for precise time-gated spectroscopy of both prompt and delayed γ rays following fission. This technique offers a non-destructive probe of special nuclear materials that is sensitive to the isotopic identity of the fissile material.

Nuclear fission with inertial confinement

CERN Document Server

Koshkarev, D G

2002-01-01

The possibility of initiating the explosive fission reaction in a small quantity of fissile material through the heavy ions beam from the powerful accelerator-driver, developed for realization of the thermonuclear synthesis in the deuterium-tritium cylindrical targets with the direct ignition, is considered. The consequences of applying this method in the nuclear engineering are discussed

Decree of 4 September 1969, Stb. 405, concerning the implementation of Sections 16, 19, paragraph 1, 21, 29, 30, paragraph 2 and 32 of the Nuclear Energy Act (Fissionable Materials, Ores and Radioactive Materials (Transport))

International Nuclear Information System (INIS)

1969-01-01

The regulations governing the transport of fissionable materials, ores and radioactive materials are embodied in this Decree, together with the regulations concerning operations involving their movements into and out of the Netherlands and their storage incidental to transport. (NEA) [fr

The production of accelerated radioactive ion beams

International Nuclear Information System (INIS)

Olsen, D.K.

1993-01-01

During the last few years, substantial work has been done and interest developed in the scientific opportunities available with accelerated radioactive ion beams (RIBs) for nuclear physics, astrophysics, and applied research. This interest has led to the construction, development, and proposed development of both first- and second-generation RIB facilities in Asia, North America, and Europe; international conferences on RIBs at Berkeley and Louvain-la-Neuve; and many workshops on specific aspects of RIB production and science. This paper provides a discussion of both the projectile fragmentation, PF, and isotope separator on-line, ISOL, approach to RIB production with particular emphasis on the latter approach, which employs a postaccelerator and is most suitable for nuclear structure physics. The existing, under construction, and proposed facilities worldwide are discussed. The paper draws heavily from the CERN ISOLDE work, the North American IsoSpin Laboratory (ISL) study, and the operating first-generation RIB facility at Louvain-la-Neuve, and the first-generation RIB project currently being constructed at ORNL

Influence of the incident particle energy on the fission product mass distribution

International Nuclear Information System (INIS)

Gomes, I. C.

1998-01-01

For 238 U targets and the five elements considered here, the best yields of neutron-rich isotopes are obtained from neutrons in the 2-20 MeV range. High energy beams of neutrons, protons, and deuterons have comparable integral yields per element to neutrons below 20 MeV, but the distributions are peaked at lower neutron numbers. This is presumably due to a higher neutron multiplicity in the pre-equilibrium stage and/or the compound nucleus/fission stage. For 235 U targets there are high yields predicted especially for thermal neutrons, and also for the fast neutron spectrum. For the high energy neutrons, protons, and deuterons 235 U has no advantage over 238 U. A detailed comparison of the relative advantages of 235 U and 238 U for radioactive beam applications is beyond the scope of this study and will be addressed in the future. The present work is the first step of a more detailed analysis of various possible one- and two-step target geometry calculated with the LAHET code system. It is intended to serve as a guide in choosing geometry and beams for future studies. It is desirable to extend this study to higher beam energies, e.g. 200 to 1000 MeV, but at this time there is very little data against which to benchmark the analysis. Additional data would also permit comparisons of isotope yields beyond the tails of the distributions presented here, to even more neutron rich isotopes

Measurement of the angular distribution of fission fragments using a PPAC assembly at CERN n{sub T}OF

Energy Technology Data Exchange (ETDEWEB)

Tarrío, D., E-mail: dtarriov@gmail.com [Universidade de Santiago de Compostela (Spain); Leong, L.S.; Audouin, L. [Centre National de la Recherche Scientifique/IN2P3 -Université Paris-Sud - IPN, Orsay (France); Duran, I.; Paradela, C. [Universidade de Santiago de Compostela (Spain); Tassan-Got, L.; Le Naour, C.; Bacri, C.O.; Petitbon, V.; Mottier, J. [Centre National de la Recherche Scientifique/IN2P3 -Université Paris-Sud - IPN, Orsay (France); Caamaño, M. [Universidade de Santiago de Compostela (Spain); Altstadt, S. [Johann-Wolfgang-Goethe Universität, Frankfurt (Germany); Andrzejewski, J. [Uniwersytet Łódzki, Lodz (Poland); Barbagallo, M. [Istituto Nazionale di Fisica Nucleare, Bari (Italy); Bécares, V. [Centro de Investigaciones Energeticas Medioambientales y Tecnológicas (CIEMAT), Madrid (Spain); Bečvář, F. [Charles University, Prague (Czech Republic); Belloni, F. [Commissariat à l’Énergie Atomique (CEA) Saclay - Irfu, Gif-sur-Yvette (France); Berthoumieux, E. [Commissariat à l’Énergie Atomique (CEA) Saclay - Irfu, Gif-sur-Yvette (France); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Billowes, J. [University of Manchester, Oxford Road, Manchester (United Kingdom); Boccone, V. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); and others

2014-04-11

A fission reaction chamber based on Parallel Plate Avalanche Counters (PPACs) was built for measuring angular distributions of fragments emitted in neutron-induced fission of actinides at the neutron beam available at the Neutron Time-Of-Flight (n{sub T}OF) facility at CERN. The detectors and the samples were tilted 45° with respect to the neutron beam direction to cover all the possible values of the emission angle of the fission fragments. The main features of this setup are discussed and results on the fission fragment angular distribution are provided for the {sup 232}Th(n,f) reaction around the fission threshold. The results are compared with the available data in the literature, demonstrating the good capabilities of this setup.

Fission product detection by means of photovoltaic cells

International Nuclear Information System (INIS)

Liatard, E.; Akrouf, S.; Bruandet, J.F.; Fontenille, A.; Glasser, F.; Stassi, P.; Tsan Ung Chan

1988-01-01

The response of photovoltaic cells to heavy ions and fission products have been tested in-beam. Their main advantages are their extremely low price, their low sensitivity to energetic light ions with respect to fission products, and the possibility to cut and fit them together to any shape without dead zone. The time output signals of a charge sensitive preamplifier connected to these cells allows fast coincidences. A resolution of 12 ns (FWHM) has been measured between two cells. (orig.)

Experimental tests of the production process of Mo-99 fission in the hot cell

International Nuclear Information System (INIS)

Sanchez M, V.; Lopez C, R.

1991-12-01

The production method of 99 Mo of fission obtains to this with a specific activity of several orders of great magnitude to the one obtained by other methods (as that of irradiation of a target constituted by an alloy or that of irradiation with neutrons of targets of molybdenum of natural isotopic composition or enriched with 98 Mo) and perhaps the most important it is that by this method hundred of Ci of 99 Mo can be obtained by production process. The development of the production process of 99 Mo of fission, is closely linked with the development of techniques for the handling of high radioactivities, particularly the handling of radioactive gases, also with the deposit and elimination of radioactive wastes and with the construction of safety targets for its irradiation in a nuclear reactor. (Author)

Fission Product Release from Spent Nuclear Fuel During Melting

International Nuclear Information System (INIS)

Howell, J.P.; Zino, J.F.

1998-09-01

The Melt-Dilute process consolidates aluminum-clad spent nuclear fuel by melting the fuel assemblies and diluting the 235U content with depleted uranium to lower the enrichment. During the process, radioactive fission products whose boiling points are near the proposed 850 degrees C melting temperature can be released. This paper presents a review of fission product release data from uranium-aluminum alloy fuel developed from Severe Accident studies. In addition, scoping calculations using the ORIGEN-S computer code were made to estimate the radioactive inventories in typical research reactor fuel as a function of burnup, initial enrichment, and reactor operating history and shutdown time.Ten elements were identified from the inventory with boiling points below or near the 850 degrees C reference melting temperature. The isotopes 137Cs and 85Kr were considered most important. This review serves as basic data to the design and development of a furnace off-gas system for containment of the volatile species

Fission theory and actinide fission data

Energy Technology Data Exchange (ETDEWEB)

Michaudon, A.

1975-06-01

The understanding of the fission process has made great progress recently, as a result of the calculation of fission barriers, using the Strutinsky prescription. Double-humped shapes were obtained for nuclei in the actinide region. Such shapes could explain, in a coherent manner, many different phenomena: fission isomers, structure in near-threshold fission cross sections, intermediate structure in subthreshold fission cross sections and anisotropy in the emission of the fission fragments. A brief review of fission barrier calculations and relevant experimental data is presented. Calculations of fission cross sections, using double-humped barrier shapes and fission channel properties, as obtained from the data discussed previously, are given for some U and Pu isotopes. The fission channel theory of A. Bohr has greatly influenced the study of low-energy fission. However, recent investigation of the yields of prompt neutrons and γ rays emitted in the resonances of {sup 235}U and {sup 239}Pu, together with the spin determination for many resonances of these two nuclei cannot be explained purely in terms of the Bohr theory. Variation in the prompt neutron and γ-ray yields from resonance to resonance does not seem to be due to such fission channels, as was thought previously, but to the effect of the (n,γf) reaction. The number of prompt fission neutrons and the kinetic energy of the fission fragments are affected by the energy balance and damping or viscosity effects in the last stage of the fission process, from saddle point to scission. These effects are discussed for some nuclei, especially for {sup 240}Pu.

The role fo the Pygmy resonance in the synthesis of heavy elements with radioactive beams

International Nuclear Information System (INIS)

Hussein, M.S.

1990-12-01

It is suggested that the inclusion of the virtual excitation of the soft giant dipole (pygmy) resonance in the calculation of the cross-section for very neutron-rich radioactive beam-induced fusion reactions may enhance the formation probability of the heavy compound nucleus produced at low excitation energy. (author)

Radioactivity Monitoring System for TRIGA 2000 Reactor Water Tank with On-Line Gamma Spectrometer

International Nuclear Information System (INIS)

Prasetyo Basuki; Sudjatmi KA

2009-01-01

One of the requirements in radiological safety in the operating condition of research reactor are the absence of radionuclide from fission product released to reactor cooling water and environment. Early detection of fission product that released from fuel element can be done by monitoring radioactivity level on primary cooling water.Reactor cooling water can be used as an important indicator in detecting radioactivity level of material fission product, when the leakage occurs. Therefore, it needs to build a monitoring system for measuring radioactivity level of cooling water directly and simple. The idea of this system is counting radioactivity water flow from reactor tank to the marinelli cube that attached to the HPGe detector on gamma spectrometer. Cooling water from tank aimed on plastic pipe to the marinelli cube. Water flows in gravitational driven to the marinelli cube, with volume flow rate 5.1 liters/minute in the inlet and 2.2 liters/minute in output. (author)

Part I: $\\beta$-delayed fission, laser spectroscopy and shape-coexistence studies with astatine beams; Part II: Delineating the island of deformation in the light gold isotopes by means of laser spectroscopy

CERN Document Server

Andreyev, Andrei

2013-01-01

Part I: $\\beta$-delayed fission, laser spectroscopy and shape-coexistence studies with astatine beams; Part II: Delineating the island of deformation in the light gold isotopes by means of laser spectroscopy

Nuclear reactions with ¹¹C and ¹⁴O radioactive ion beams

Energy Technology Data Exchange (ETDEWEB)

Guo, Fanqing [Univ. of California, Berkeley, CA (United States)

2004-01-01

Radioactive ion beams (RIBs) have been shown to be a useful tool for studying proton-rich nuclides near and beyond the proton dripline and for evaluating nuclear models. To take full advantage of RIBs, Elastic Resonance Scattering in Inverse Kinematics with Thick Targets (ERSIKTT), has proven to be a reliable experimental tool for investigations of proton unbound nuclei. Following several years of effort, Berkeley Experiments with Accelerated Radioactive Species (BEARS), a RIBs capability, has been developed at the Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. The current BEARS provides two RIBs: a ¹¹C beam of up to 2x10⁸ pps intensity on target and an ¹⁴O beam of up to 3x10⁴ pps intensity. While the development of the ¹¹C beam has been relatively easy, a number of challenges had to be overcome to obtain the ¹⁴O beam. The excellent ¹¹C beam has been used to investigate several reactions. The first was the ¹⁹⁷Au(¹¹C,xn)^208-xnAt reaction, which was used to measure excitation functions for the 4n to 8n exit channels. The measured cross sections were generally predicted quite well using the fusion-evaporation code HIVAP. Possible errors in the branching ratios of ?? decays from At isotopes as well as the presence of incomplete fusion reactions probably contribute to specific overpredictions. ¹⁵F has been investigated by the p(¹⁴O,p)14O reaction with the ERSIKTT technology. Several ¹⁴O+p runs have been performed. Excellent energy calibration was obtained using resonances from the p(¹⁴N,p)¹⁴N reaction in inverse kinematics, and comparing the results to those obtained earlier with normal kinematics. The differences between ¹⁴N+p and ¹⁴O+p in the stopping power function have been evaluated for better energy calibration. After careful calibration, the energy levels of 15F

A cylindrical Penning trap for capture, mass selective cooling, and bunching of radioactive ion beams

International Nuclear Information System (INIS)

Raimbault-Hartmann, H.; Bollen, G.; Beck, D.; Koenig, M.; Kluge, H.-J.; Schwarz, S.; Schark, E.; Stein, J.; Szerypo, J.

1997-01-01

A Penning trap ion accumulator, cooler, and buncher for low-energy ion beams has been developed for the ISOLTRAP mass spectrometer at ISOLDE/CERN. A cylindrical electrode configuration is used for the creation of a nested trapping potential. This is required for efficient accumulation of externally produced ions and for high-mass selectivity by buffer gas cooling. The design goal of a mass resolving power of about 1 x 10 5 has been achieved. Isobar separation has been demonstrated for radioactive rare-earth ion beams delivered by the ISOLDE on-line mass separator. (orig.)

A cylindrical Penning trap for capture, mass selective cooling, and bunching of radioactive ion beams

CERN Document Server

Raimbault-Hartmann, H; Bollen, G; König, M; Kluge, H J; Schark, E; Stein, J; Schwarz, S; Szerypo, J

1997-01-01

A Penning trap ion accumulator, cooler, and buncher for low energy ion beams has been developed for the ISOLTRAP mass spectrometer at ISOLDE/CERN. A cylindrical electrode configuration is used for the creation of a nested trapping potential. This is required for efficient accumulation of externally produced ions and for high mass selectivity by buffer gas cooling. The design goal of a mass resolving power of about $1\\cdot 10^{5}$ has been achieved. Isobar separation has been demonstrated for radioactive rare earth ion beams delivered by the ISOLDE on-line mass separator.

First Nuclear Reaction Experiment with Stored Radioactive 56Ni Beam and Internal Hydrogen and Helium Targets

NARCIS (Netherlands)

Egelhof, P.; Bagchi, Soumya; Csatlós, M.; Dillmann, I.; Dimopoulou, C.; Furuno, T; Geissel, H.; Gernhauser, R.; Kalantar-Nayestanaki, Nasser; Kuilman, M.; Mahjour-Shafiei, M.; Najafi, M.A.; Rigollet, C.; Streicher, B.

2014-01-01

The investigation of light-ion induced direct reactions using stored and cooled radioactive beams, interacting with internal targets of storage rings, can lead to substantial advantages over external target experiments, in particular for direct reaction experiments in inverse kinematics at very low

Study of the irradiation given by cylindrical drums containing radioactive sludges; Etude de l'irradiation a proximite d'un fut cylindrique de stockage de boues radioactives

Energy Technology Data Exchange (ETDEWEB)

Bourdrez, J.

1960-05-13

Some data on shielding are presented concerning irradiation given by drums containing radioactive sludge (fission products). (author) [French] Sont exposes differents resultats de calculs de protection relatifs a l'intensite d'irradiation γ donnee par un fut rempli de boues de produits de fission radioactifs. (auteur)

Radioactive particles revealed by electron microscopy. Chemical and physical properties of radioactive particles in aerosol samples emitted during the early stage of Fukushima Dai-ichi Nuclear Power Plant accident

International Nuclear Information System (INIS)

Adachi, Kouji

2015-01-01

Water-insoluble radioactive materials emitted during an early stage of the Fukushima Dai-ichi Nuclear Power Plant accident in 2011 were identified, and their chemical and physical properties were characterized as particulate matters. In this report, studies on radioactive particles collected from filter samples in Tsukuba on March 14–15, 2011 are summarized. Their compositions, chemical states, sizes, shapes, crystallinity, and hygroscopicity were analyzed using microscopic analyses such as electron microscopy and synchrotron with a micro-beam. The results indicate that they include Cs, Fe, and Zn as well as elements from fission products and are water insoluble, spherical-glassy particles with ca. 2 micrometer in size. Understanding of their detailed properties is significant to improve the numerical models during the accident and to understand their occurrences in soil as well as the accident itself. In addition to the water-insoluble radioactive materials, water-soluble radioactive materials, which were likely emitted in different events during the accident, should be investigated to have comprehensive understanding of the accident and its environmental effects. More samples from various environments such as soil will be needed, and more detailed chemical and physical analyses will help to understand their formation process, influences on human health, and long term decrements in ambient conditions. (author)

Fission modelling with FIFRELIN

International Nuclear Information System (INIS)

Litaize, Olivier; Serot, Olivier; Berge, Leonie

2015-01-01

The nuclear fission process gives rise to the formation of fission fragments and emission of particles (n,γ, e - ). The particle emission from fragments can be prompt and delayed. We present here the methods used in the FIFRELIN code, which simulates the prompt component of the de-excitation process. The methods are based on phenomenological models associated with macroscopic and/or microscopic ingredients. Input data can be provided by experiment as well as by theory. The fission fragment de-excitation can be performed within Weisskopf (uncoupled neutron and gamma emission) or a Hauser-Feshbach (coupled neutron/gamma emission) statistical theory. We usually consider five free parameters that cannot be provided by theory or experiments in order to describe the initial distributions required by the code. In a first step this set of parameters is chosen to reproduce a very limited set of target observables. In a second step we can increase the statistics to predict all other fission observables such as prompt neutron, gamma and conversion electron spectra but also their distributions as a function of any kind of parameters such as, for instance, the neutron, gamma and electron number distributions, the average prompt neutron multiplicity as a function of fission fragment mass, charge or kinetic energy, and so on. Several results related to different fissioning systems are presented in this work. The goal in the next decade will be i) to replace some macroscopic ingredients or phenomenological models by microscopic calculations when available and reliable, ii) to be a support for experimentalists in the design of detection systems or in the prediction of necessary beam time or count rates with associated statistics when measuring fragments and emitted particle in coincidence iii) extend the model to be able to run a calculation when no experimental input data are available, iv) account for multiple chance fission and gamma emission before fission, v) account for the

Fusion-fission dynamics and perspectives of future experiments

International Nuclear Information System (INIS)

Zagrebaev, V.I.; Itkis, M.G.; Oganessian, Yu.Ts.

2003-01-01

The paper is focused on reaction dynamics of superheavy-nucleus formation and decay at beam energies near the Coulomb barrier. The aim is to review the things we have learned from recent experiments on fusion-fission reactions leading to the formation of compound nuclei with Z ≥ 102 and from their extensive theoretical analysis. Major attention is paid to the dynamics of formation of very heavy compound nuclei taking place in strong competition with the process of fast fission (quasifission). The choice of collective degrees of freedom playing a fundamental role and finding the multidimensional driving potential and the corresponding dynamic equation regulating the whole process are discussed. A possibility of deriving the fission barriers of superheavy nuclei directly from performed experiments is of particular interest here. In conclusion, the results of a detailed theoretical analysis of available experimental data on the 'cold' and 'hot' fusion-fission reactions are presented. Perspectives of future experiments are discussed along with additional theoretical studies in this field needed for deeper understanding of the fusion-fission processes of very heavy nuclear systems

Experiments with radioactive nuclear beams II; Experimentos con haces nucleares radiactivos II

Energy Technology Data Exchange (ETDEWEB)

Aguilera R, E.F.; Martinez Q, E.; Gomez C, A.; Lizcano C, D.; Garcia M, H.; Rosales M, P. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2001-12-15

The studies of nuclear reactions with heavy ions have been carried out for years for the group of heavy ions of the laboratory of the Accelerator of the ININ. Especially in the last years the group has intruded in the studies of nuclear reactions with radioactive beams, frontier theme at world level. Presently Technical Report is presented in detailed form the experimental methods and the analysis procedures of the research activities carried out by the group. The chpater II is dedicated to the procedures used in the analysis of the last two experiments with radioactive beams carried out by the group. In the chapter III is presented the procedure followed to carrying out an extended analysis with the CCDEF code, to consider the transfer channel of nucleons in the description of the fusion excitation functions of a good number of previously measured systems by the group. Finally, in the chapter IV the more important steps to continue in the study of the reaction {sup 12}C + {sup 12}C experiment drifted to be carried out using the available resources of the Tandem Accelerator Laboratory of the ININ are described. At the end of each chapter some of the more representative results obtained in the analysis are presented and emphasis on the scientific production generated by the group for each case is made. (Author)

Fission product vapour - aerosol interactions in the containment: simulant fuel studies

International Nuclear Information System (INIS)

Beard, A.M.; Benson, C.G.; Bowsher, B.R.

1988-12-01

Experiments have been conducted in the Falcon facility to study the interaction of fission product vapours released from simulant fuel samples with control rod aerosols. The aerosols generated from both the control rod and fuel sample were chemically distinct and had different deposition characteristics. Extensive interaction was observed between the fission product vapours and the control rod aerosol. The two dominant mechanisms were condensation of the vapours onto the aerosol, and chemical reactions between the two components; sorption phenomena were believed to be only of secondary importance. The interaction of fission product vapours and reactor materials aerosols could have a major impact on the transport characteristics of the radioactive emission from a degrading core. (author)

Measurement of fission cross-section of actinides at n_TOF for advanced nuclear reactors

CERN Document Server

Calviani, Marco; Montagnoli, G; Mastinu, P

2009-01-01

The subject of this thesis is the determination of high accuracy neutron-induced fission cross-sections of various isotopes - all of which radioactive - of interest for emerging nuclear technologies. The measurements had been performed at the CERN neutron time-of-flight facility n TOF. In particular, in this work, fission cross-sections on 233U, the main fissile isotope of the Th/U fuel cycle, and on the minor actinides 241Am, 243Am and 245Cm have been analyzed. Data on these isotopes are requested for the feasibility study of innovative nuclear systems (ADS and Generation IV reactors) currently being considered for energy production and radioactive waste transmutation. The measurements have been performed with a high performance Fast Ionization Chamber (FIC), in conjunction with an innovative data acquisition system based on Flash-ADCs. The first step in the analysis has been the reconstruction of the digitized signals, in order to extract the information required for the discrimination between fission fragm...

Radioactive beam EXperiments at ISOLDE : Coulomb excitation and neutron transfer reactions of exotic nuclei.

CERN Multimedia

Kugler, E; Ratzinger, U; Wenander, F J C

2002-01-01

% IS347 \\\\ \\\\We propose to perform a pilot experiment to study very neutron rich (A<32) Na-Mg and (A<52) K-Ca isotopes in the region around the neutron shell closures of N=20 and N=28 after Coulomb excitation and neutron transfer, and to demonstrate highly efficient and cost-effective ways to bunch, charge-state breed and accelerate already existing mass-separated singly-charged radioactive ion beams. \\\\ \\\\To do this we plan to accelerate the ISOLDE beams up to 2~MeV/u by means of a novel acceleration scheme and to install an efficient $\\gamma$-ray array for low-multiplicity events around the target position.

Study of fission fragments produced by 14N + 235U reaction

International Nuclear Information System (INIS)

Yalcinkaya, M.; Erduran, M.N.; Ganioglu, E.; Akkus, B.; Bostan, M.; Gurdal, G.; Erturk, S.; Balabanski, D.; Minkova, A.; Danchev, M.

2005-01-01

This work was performed to understand the structure of neutron rich fission fragments around ∼ 130 region. A thin metallic 235 U target was bombarded by 14 N beam with 10 MeV/A from the Separated Sector Cyclotron at the National Accelerator Centre, Cape Town, South Africa. The main goal to detect and identify fission fragments and to obtain their mass distribution was achieved by using Solar Cell detectors in the AFRODITE (African Omnipurpose Detector for Innovative Techniques and Experiments) spectrometer. The X-rays emitted from fission fragments were detected by LEP detectors and γ rays emitted from excited states of the fission fragments were detected by CLOVER detectors in the spectrometer. (author)

Fission Fragment Yield Data in Support of Advanced Reactor Technology

Energy Technology Data Exchange (ETDEWEB)

Hecht, Adam [Univ. of New Mexico, Albuquerque, NM (United States)

2017-11-21

Within the 3 year POP we propose to continue to test and further develop the fission spectrometers, to do development tests and full data acquisition run at the national laboratory neutron beam facilities, to measure correlated fission fragment yields at low neutron energies with 235 U fission targets, and make these data available to the nuclear community. The spectrometer development will be both on the university based r\\prototype and on the National Laboratory Spectrometer, and measurements will be performed with both. Over the longer time frame of the collaboration, we will take data over a range of low energies, and use other fission targets available to the laboratory. We will gather energy specific fragment distributions and reaction cross sections. We will further develop the data acquisition capabilities to take correlated fission fragment'gamma ray/neurton data, all on an event-by-event basis. This really is an enabling technology.

Inverse kinematics technique for the study of fission-fragment isotopic yields at GANIL energies

International Nuclear Information System (INIS)

Delaune, O.

2012-01-01

The characteristics of the fission-products distributions result of dynamical and quantum properties of the deformation process of the fissioning nucleus. These distributions have also an interest for the conception of new nuclear power plants or for the transmutation of the nuclear wastes. Up to now, our understanding of the nuclear fission remains restricted because of experimental limitations. In particular, yields of the heavy fission products are difficult to get with precision. In this work, an innovative experimental technique is presented. It is based on the use of inverse kinematics coupled to the use of a spectrometer, in which a 238 U beam at 6 or 24 A MeV impinges on light targets. Several actinides, from 238 U to 250 Cf, are produced by transfer or fusion reactions, with an excitation energy ranges from ten to few hundreds MeV depending on the reaction and the beam energy. The fission fragments of these actinides are detected by the VAMOS spectrometer or the LISE separator. The isotopic yields of fission products are completely measured for different fissioning systems. The neutron excess of the fragments is used to characterise the isotopic distributions. Its evolution with excitation energy gives important insights on the mechanisms of the compound-nucleus formation and its deexcitation. Neutron excess is also used to determine the multiplicity of neutrons evaporated by the fragments. The role of the proton and neutron shell effects into the formation of fission fragments is also discussed. (author) [fr

Yrast spectroscopy in {sup 49-51}Ti via fusion-evaporation reaction induced by a radioactive beam

Energy Technology Data Exchange (ETDEWEB)

Niikura, M.; Ideguchi, E.; Michimasa, S.; Ota, S.; Shimoura, S.; Wakabayashi, Y. [University of Tokyo, Center for Nuclear Study, Wako, Saitama (Japan); Aoi, N.; Baba, H.; Fukuchi, T.; Ichikawa, Y.; Kubo, T.; Kurokawa, M.; Ohnishi, T.; Suzuki, H.; Yoshida, K. [RIKEN Nishina Center, Wako, Saitama (Japan); Iwasaki, H.; Onishi, T.K.; Suzuki, D. [University of Tokyo, Department of Physics, Tokyo (Japan); Liu, M.; Zheng, Y. [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China)

2009-12-15

In-beam {gamma} -ray spectroscopy of high-spin states in {sup 49-51}Ti was performed via the fusion-evaporation reaction using a radioactive beam. By excitation function and {gamma} - {gamma} coincidence analysis, yrast high-spin levels up to I=(21/2{sup -}),(11{sup +}),(17/2{sup -}) in {sup 49-51}Ti were determined. The levels were compared with full-pf -shell model calculation. The level structure indicates the persistency of the N=28 shell gap at yrast states in {sup 49-51}Ti. (orig.)

Fission Detection Using the Associated Particle Technique

International Nuclear Information System (INIS)

R.P. Keegan; J.P. Hurley; J.R. Tinsley; R. Trainham; S.C. Wilde

2008-01-01

A beam of tagged 14 MeV neutrons from the deuterium-tritium (DT) reaction is used to induce fission in a target composed of depleted uranium. The generator yield is 10 7 neutrons/second radiated into a 4 x 4 in. NaI detectors are used for gamma-ray detection. The fission process is known to produce multiple gamma-rays and neutrons. Triple coincidences (α-γ-γ) are measured as a function of neutron flight time up to 90 ns after fission, where the α-particle arises from the DT reaction. A sudden increase in the triple coincidence rate at the location of the material is used to localize and detect fission in the interrogated target. Comparisons are made with experiment runs where lead, tungsten, and iron were used as target materials. The triple coincidence response profile from depleted uranium is noted to be different to those observed from the other target materials. The response from interrogation targets composed of fissile material is anticipated to be even more unique than that observed from depleted uranium

Treatment of Radioactive Waste Generated from the Production of Molybdenum-99 Radioisotope

International Nuclear Information System (INIS)

Aisyah; Herlan Martono

2007-01-01

The 99 Mo is produced as the parent radionuclide for 99m Tc radioisotope which is used as medical radiodiagnostic for certain disease. In Indonesia 99 Mo is produced by irradiating target of high enriched U in the reactor. The characteristics of radioactive waste from the production of 99 Mo depend on the U enrichment of the target and the irradiation time. The characteristic of the radioactive waste can be directly determined by laboratory analysis or by ORIGEN 2 code. Producing 99 Mo from high enriched uranium target will produce radioactive waste containing 235 U, 238 U and fission product, while from low enriched uranium target will produce radioactive waste containing large amount of 239 Pu. Plutonium-239 is a long half life actinide that need to be separated from the fission product due to a different treatment is required. The fission product, after it is allowed to decay then needs to be categorized as low or medium level waste, while 239 Pu are categorized as transuranic waste. The disposal of low and medium level waste are stored in near surface disposal, while the disposal of transuranic waste is stored in a geologic formation. (author)

Characterization of the solid radioactive waste from Cernavoda NPP

International Nuclear Information System (INIS)

Iordache, M.; Lautaru, V.; Bujoreanu, D.

2005-01-01

During the operation of a nuclear plant significant quantities of radioactive waste result that have a very large diversity. At Cernavoda NPP large amounts of wastes are either non-radioactive wastes or radioactive wastes, each of these being managed completely different from each other. For a CANDU type reactor, the occurrence of radioactive wastes is due to contamination with the following types of radioactive substances: - fission products resulting from nuclear fuel burning; - activated products from materials composing the technological systems; - activated products in process fluids. Radioactive wastes can be in solid, liquid or gas form. At Cernavoda NPP the solid wastes represent about 70% of the waste volume which is produced during plant operation and as a consequence of maintenance and decontamination operations. The most important types of solid wastes that are obtained and then handled, processed (if necessary) and temporarily stored are: solid low-level radioactive wastes (classified as compactible and non-compactible), solid medium radioactive wastes, spent resins, used filters and filter cartridges. The liquid radioactive waste class includes organic liquids (used oil, scintillator liquids and used solvents) and aqueous wastes resulting from process system operating, from decontamination and maintenance operations. Radioactive gas wastes occur subsequently to the fission process inside the fuel elements as well as due to the neutron activation of process fluids in the reactor systems. As result of plant operation, iodine, noble gases, tritium and radioactive particles occur and are passed toward the ventilation stack in a controlled manner so that environmental release of radioactive materials with concentrations exceeding the maximum permissible level could not occur. (authors)

Final report on fabrication and study of SYNROC containing radioactive waste elements

International Nuclear Information System (INIS)

Reeve, K.D.; Levins, D.M.; Seatonberry, B.W.; Ryan, R.K.; Hart, K.P.; Stevens, G.T.

1987-01-01

Two facilities for the fabrication and testing of Synroc samples containing separate additions of the transuranic actinides americium, plutonium, curium and neptunium, a fission product solution, and two radioisotopes of caesium and strontium were designed, built and operated by the AAEC at the Lucas Heights Research Laboratories. Twenty-one 75 g batches of radioactive Synroc were made and representative samples were characterised by alpha track etching, scanning electron microscopy and aqueous leach testing, mostly at 70 deg C. Where comparisons were possible, radioactive fission products behaved as expected from non-radioactive tests. The leaching behaviour of the actinides was complex but as a group they were the least leachable of all the elements studied

Upgrade of the facility EXOTIC for the in-flight production of light Radioactive Ion Beams

Energy Technology Data Exchange (ETDEWEB)

Mazzocco, M., E-mail: marco.mazzocco@pd.infn.it [Dipartimento di Fisica e Astronomia, Universitá di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); INFN-Sezione di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); Torresi, D.; Strano, E. [Dipartimento di Fisica e Astronomia, Universitá di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); INFN-Sezione di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); Boiano, A. [INFN-Sezione di Napoli, Via Cinthia, I-80126 Napoli (Italy); Boiano, C. [INFN-Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Costa, L. [INFN-LNL, Viale dell’Università 2, I-35020 Legnaro, PD (Italy); Glodariu, T. [NIPNE, 407 Atomistilor Street, 077125 Magurele (Romania); Guglielmetti, A. [INFN-Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Dipartimento di Fisica,Università di Milano, Via Celoria 16, I-20133 Milano (Italy); La Commara, M. [INFN-Sezione di Napoli, Via Cinthia, I-80126 Napoli (Italy); Dipartimento di Scienze Fisiche, Università di Napoli, Via Cinthia, I-80126 Napoli (Italy); Parascandolo, C. [Dipartimento di Fisica e Astronomia, Universitá di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); INFN-Sezione di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); Pierroutsakou, D. [INFN-Sezione di Napoli, Via Cinthia, I-80126 Napoli (Italy); Signorini, C.; Soramel, F. [Dipartimento di Fisica e Astronomia, Universitá di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); INFN-Sezione di Padova, Via F. Marzolo 8, I-35131 Padova (Italy); Stroe, L. [NIPNE, 407 Atomistilor Street, 077125 Magurele (Romania)

2013-12-15

Highlights: • Production of in-flight Radioactive Ion Beams via two-body reactions. • Development of a cryogenic gas target. • Event-by-event tracking via Parallel Plate Avalanche Counters (PPACs). -- Abstract: The facility EXOTIC for the in-flight production of light weakly-bound Radioactive Ion Beams (RIBs) has been operating at INFN-LNL since 2004. RIBs are produced via two-body reactions induced by high intensity heavy-ion beams impinging on light gas targets and selected by means of a 30°-dipole bending magnet and a 1-m long Wien filter. The facility has been recently upgraded (i) by developing a cryogenic gas target, (ii) by replacing the power supplies of the middle lenses of the two quadrupole triplets, (iii) by installing two y-steerers and (iv) by placing two Parallel Plate Avalanche Counters upstream the secondary target to provide an event-by-event reconstruction of the position hit on the target. So far, RIBs of {sup 7}Be, {sup 8}B and {sup 17}F in the energy range 3–5 MeV/u have been produced with intensities about 3 × 10{sup 5}, 1.6 × 10{sup 3} and 10{sup 5} pps, respectively. Possible light RIBs (up to Z = 10) deliverable by the facility EXOTIC are also reviewed.

Design considerations of fission and corrosion product in primary system of MONJU

International Nuclear Information System (INIS)

Yanagisawa, T.; Akagane, K.; Yamamoto, K.; Kawashima, K.

1976-01-01

General influence of fission and corrosion products in primary system on MONJU plant design is reviewed. Various research and development works are now in progress to decrease the generation rate, to remove the products more effectively and to develop the methods of evaluation the behaviour of radioactive products. The inventory and distribution of fission and corrosion products in the primary circuit of MONJU are given. The radiation levels on the primary components are estimated to be several roentgens per hour. (author)

Development of Fission Mo-99 Process for LEU Dispersion Target

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Kon; Lee, Su Seung; Hong, Soon Bog; Jang, Kyung Duk; Park, Ul Jae; Lee, Jun Sig [KAERI, Daejeon (Korea, Republic of)

2016-05-15

KAERI (Korea Atomic Energy Research Institute) is developing LEU-based fission {sup 99}Mo production process which is connected to the new research reactor (Kijang New Research Reactor, KJRR), which is being constructed in Gijang, Busan, Korea. Historically, the most fission {sup 99}Mo producers have been used highly enriched uranium (HEU) targets so far. However, to reduce the use of HEU in private sector for non-proliferation, {sup 99}Mo producers are forced to convert their HEU-based process to use low enriched uranium (LEU) targets. Economic impact of a target conversion from HEU to LEU is significant. Overall cost for the production of the fission {sup 99}Mo increases significantly with the conversion of fission {sup 99}Mo targets from HEU to LEU. It is not only because the yield of LEU is only 50% of HEU, but also because radioactive waste production increases 200%. On the basis, worldwide efforts on the development of {sup 99}Mo production process that is optimized for the LEU target become an important issue. In this study, fission {sup 99}Mo process with non-irradiated LEU targets was presented except separation and purification steps. Pre- and post-irradiation tests of the fission {sup 99}Mo target will be done in 4th quarter of 2016.

Development of Fission Mo-99 Process for LEU Dispersion Target

International Nuclear Information System (INIS)

Lee, Seung Kon; Lee, Su Seung; Hong, Soon Bog; Jang, Kyung Duk; Park, Ul Jae; Lee, Jun Sig

2016-01-01

KAERI (Korea Atomic Energy Research Institute) is developing LEU-based fission 99 Mo production process which is connected to the new research reactor (Kijang New Research Reactor, KJRR), which is being constructed in Gijang, Busan, Korea. Historically, the most fission 99 Mo producers have been used highly enriched uranium (HEU) targets so far. However, to reduce the use of HEU in private sector for non-proliferation, 99 Mo producers are forced to convert their HEU-based process to use low enriched uranium (LEU) targets. Economic impact of a target conversion from HEU to LEU is significant. Overall cost for the production of the fission 99 Mo increases significantly with the conversion of fission 99 Mo targets from HEU to LEU. It is not only because the yield of LEU is only 50% of HEU, but also because radioactive waste production increases 200%. On the basis, worldwide efforts on the development of 99 Mo production process that is optimized for the LEU target become an important issue. In this study, fission 99 Mo process with non-irradiated LEU targets was presented except separation and purification steps. Pre- and post-irradiation tests of the fission 99 Mo target will be done in 4th quarter of 2016

Status report on actinide and fission product transmutation studies

International Nuclear Information System (INIS)

1997-06-01

The management of radioactive waste is one of the key issues in today's political and public discussions on nuclear energy. One of the fields that looks into the future possibilities of nuclear technology is the neutronic transmutation of actinides and of some most important fission products. Studies on transmutation of actinides are carried out in various countries and at an international level. This status report which gives an up-to-date general overview of current and planned research on transmutation of actinides and fission products in non-OECD countries, has been prepared by a Technical Committee meeting organized by the IAEA in September 1995. 168 refs, 16 figs, 34 tabs

Report on Fission Time Projection Chamber M3FT-12IN0210052

Energy Technology Data Exchange (ETDEWEB)

James K. Jewell

2012-08-01

The Time Projection Chamber is a collaborative effort to implement an innovative approach and deliver unprecedented fission measurements to DOE programs. This 4?-detector system will provide unrivaled 3-D data about the fission process. Shown here is a half populated TPC (2?) at the LLNL TPC laboratory as it undergoes testing before being shipped to LANSCE for beam experiments.

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

International Nuclear Information System (INIS)

Duarte, S.B.; Tavares, O.A.P.; Guzman, F.; Dimarco, A.; Garcia, F.; Goncalves, 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 with Werner-Wheeler's inertia coefficient V 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, τ c is presented for all possible cases of spontaneous nuclear break-up such that -7.30 10 τ c [S] 10 (τ/τ c ) > -17.0, where τ is the total half-life of the parent nucleus. (author)

A separate effect study of the influence of metallic fission products on CsI radioactive release from nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Di Lemma, F.G., E-mail: fidelma.dilemma@gmail.com [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, 2629 JB (Netherlands); Colle, J.Y., E-mail: jean-yves.colle@ec.europa.eu [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Beneš, O. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Konings, R.J.M. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Department of Radiation Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, 2629 JB (Netherlands)

2015-10-15

The chemistry of cesium and iodine is of main importance to quantify the radioactive release in case of a nuclear reactor accident, or sabotage involving irradiated nuclear materials. We studied the interaction of CsI with different metallic fission products such as Mo and Ru. These elements can be released from nuclear fuel when exposed to oxidising conditions, as in the case of contact of overheated nuclear fuel with air (e.g. in a spent fuel cask sabotage, uncovering of a spent fuel pond, or air ingress accidents). Experiments were performed by vaporizing mixtures of the compounds in air, and analysing the produced aerosols in view of a possible gas–gas and gas–aerosol reactions between the compounds. These results were compared with the gaseous species predicted by thermochemical equilibrium calculations and experimental equilibrium vaporization tests using Knudsen Effusion Mass Spectrometry.

Spallation reaction study for fission products in nuclear waste: Cross section measurements for 137Cs, 90Sr and 107Pd on proton and deuteron

Directory of Open Access Journals (Sweden)

Wang He

2017-01-01

Full Text Available Spallation reactions for the long-lived fission products 137Cs, 90Sr and 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. and the cross-section differences between the proton and deuteron are found to be larger for lighter fragments. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intra-nuclear cascade and evaporation processes.

Fission, fusion and the energy crisis

Energy Technology Data Exchange (ETDEWEB)

Hunt, S E [Aston Univ., Birmingham (UK)

1980-01-01

The subject is covered in chapters, entitled: living on capital (energy reserves and consumption forecasts); the atom and its nucleus, mass and energy; fission and the bomb; the natural uranium reactor; enriched reactors; control and safety; long-term economics (the breeder reactions and nuclear fuel reserves); short-term economics (cost per kilowatt hour); national nuclear power programmes; nuclear power and the environment (including reprocessing, radioactive waste management, public relations); renewable energy sources; the fusion programme; summary and comment.

Fission product nuclear data obtained by use of an on-line mass spectrometer

International Nuclear Information System (INIS)

Reeder, P.L.; Wright, J.F.; Anderl, R.A.

1975-01-01

A Spectrometer for On-Line Analysis of Radionuclides (SOLAR) has been installed at a 1 MW TRIGA reactor at Washington State University. Fission product ions from a combination target/ion source located within the thermal column are brought out to a 60 0 magnetic sector mass spectrometer. Surface ionization provides copious beams of Rb + and Cs + ions and less intense beams of Br - and I - ions with negligible contamination by other elements. About 40 fission product nuclides can thus be chemically and physically separated in times of less than 1 second. Past results on independent and cumulative fission yields along with measurements of half-lives of some very neutron-rich nuclides are presented. Current work on delayed-neutron emission probabilities and energy spectra of delayed neutrons from individual nuclides is described. (7 tables, 2 figures) (U.S.)

Energy from nuclear fission()

Science.gov (United States)

Ripani, M.

2015-08-01

The main features of nuclear fission as physical phenomenon will be revisited, emphasizing its peculiarities with respect to other nuclear reactions. Some basic concepts underlying the operation of nuclear reactors and the main types of reactors will be illustrated, including fast reactors, showing the most important differences among them. The nuclear cycle and radioactive-nuclear-waste production will be also discussed, along with the perspectives offered by next generation nuclear assemblies being proposed. The current situation of nuclear power in the world, its role in reducing carbon emission and the available resources will be briefly illustrated.

Immobilization of fission products in phosphate ceramic waste forms

Energy Technology Data Exchange (ETDEWEB)

Singh, D.; Wagh, A. [Argonne National Lab., IL (United States)

1997-10-01

Chemically bonded phosphate ceramics (CBPCs) have several advantages that make them ideal candidates for containing radioactive and hazardous wastes. In general, phosphates have high solid-solution capacities for incorporating radionuclides, as evidenced by several phosphates (e.g., monazites and apatites) that are natural analogs of radioactive and rare-earth elements. The phosphates have high radiation stability, are refractory, and will not degrade in the presence of internal heating by fission products. Dense and hard CBPCs can be fabricated inexpensively and at low temperature by acid-base reactions between an inorganic oxide/hydroxide powder and either phosphoric acid or an acid-phosphate solution. The resulting phosphates are extremely insoluble in aqueous media and have excellent long-term durability. CBPCs offer the dual stabilization mechanisms of chemical fixation and physical encapsulation, resulting in superior waste forms. The goal of this task is develop and demonstrate the feasibility of CBPCs for S/S of wastes containing fission products. The focus of this work is to develop a low-temperature CBPC immobilization system for eluted {sup 99}Tc wastes from sorption processes.

Final report: Accelerated beta decay for disposal of fission fragment wastes

International Nuclear Information System (INIS)

Reiss, Howard R.

2000-01-01

The fundamental theory of the interaction of intense, low-frequency electromagnetic fields with certain radioactive nuclei has been fully formulated. The nuclei are of the type that exists in high-level radioactive wastes that are end products of the production of energy from nuclear fission. The basic physical mechanisms that underlie the coupling of the applied field to the nucleus have been identified. Both the basic theory and numerical predictions that stem from it support the conclusion that high-level radioactive wastes can be disposed of by substantially accelerating the rate of radioactive decay. Some old experiments on the acceleration of this type of radioactivity, with results that were not understood at the time, have been re-examined. Their interpretation is now clear, and the experiments are found to be in agreement with the theory

Coulomb Excitation of a Neutron-Rich $^{88}$Kr Beam Search for Mixed Symmetry States

CERN Multimedia

Andreoiu, C; Napiorkowski, P J; Iwanicki, J S

2002-01-01

We propose to use the ISOLDE/REX/MINIBALL/CD set-up to perform a Coulomb Excitation experiment with a $^{88}$Kr radioactive beam. The motivation includes a search for $Mixed$ $Symmetry$ states predicted by the IBM-2 model, gathering more spectroscopy data about the $^{88}$Kr nucleus and extending shape coexistence studies (performed previously by the proposers for neutron-deficient Kr isotopes) to the neutron-rich side. The proposed experiment will provide data complementary to the Coulomb Excitation of a relativistic $^{88}$Kr beam proposed by D. Tonev et al. for a RISING experiment. A total of 12 days of beam time is necessary for the experiment, equally divided into two runs. One run with a 2.2 MeV/A beam energy on a $^{48}$Ti target and a second run with the maximum available REX energy of 3.1 MeV/A on a $^{208}$Pb target are requested. Using either a UC$_{x}$ or ThC$_{x}$ fissioning primary target coupled with a plasma source by a cooled transfer line seems to be the best choice for the proposed experime...

Exhaust gas cleaning system for handling radioactive fission and activation gases

International Nuclear Information System (INIS)

Queiser, H.; Schwarz, H.

1975-01-01

An exhaust gas cleaning system utilizing the principle of delaying radioactive gases to permit their radioactive decay to a level acceptable for release to the atmosphere, comprising an adsorbent for adsorbing radioactive gas and a container for containing the adsorbent and for constraining gas to flow through the adsorbent, the adsorbent and the container forming simultaneously an adsorptive delay section and a mechanical delay section, by means of a predetermined ratio of volume of voids in the adsorbent to total volume of the container containing the adsorbent, for delaying radioactive gas to permit its radioactive decay to a level acceptable for release to the atmosphere is described. A method of using an adsorbent for cleaning a radioactive gas containing an isotope which is adsorbed by the adsorbent and containing an isotope whose adsorption by the adsorbent is low as compared to the isotope which is adsorbed and which is short-lived as compared to the isotope which is adsorbed, comprising constraining the gas to flow through the adsorbent with the retention time for the isotope which is adsorbed being at least the minimum for permitting radioactive decay to a level acceptable for release to the atmosphere and with the retention time for the isotope of relatively low adsorption and relatively short life being at least the minimum for permitting radioactive decay to a level acceptable for release to the atmosphere is also described. (U.S.)

Advantages of Production of New Fissionable Nuclides for the Nuclear Power Industry in Hybrid Fusion-Fission Reactors

Science.gov (United States)

Tsibulskiy, V. F.; Andrianova, E. A.; Davidenko, V. D.; Rodionova, E. V.; Tsibulskiy, S. V.

2017-12-01

A concept of a large-scale nuclear power engineering system equipped with fusion and fission reactors is presented. The reactors have a joint fuel cycle, which imposes the lowest risk of the radiation impact on the environment. The formation of such a system is considered within the framework of the evolution of the current nuclear power industry with the dominance of thermal reactors, gradual transition to the thorium fuel cycle, and integration into the system of the hybrid fusion-fission reactors for breeding nuclear fuel for fission reactors. Such evolution of the nuclear power engineering system will allow preservation of the existing structure with the dominance of thermal reactors, enable the reprocessing of the spent nuclear fuel (SNF) with low burnup, and prevent the dangerous accumulation of minor actinides. The proposed structure of the nuclear power engineering system minimizes the risk of radioactive contamination of the environment and the SNF reprocessing facilities, decreasing it by more than one order of magnitude in comparison with the proposed scheme of closing the uranium-plutonium fuel cycle based on the reprocessing of SNF with high burnup from fast reactors.

Theoretical study on production of heavy neutron-rich isotopes around the N=126 shell closure in radioactive beam induced transfer reactions

Directory of Open Access Journals (Sweden)

Long Zhu

2017-04-01

Full Text Available In order to produce more unknown neutron-rich nuclei around N=126, the transfer reactions 136Xe + 198Pt, 136–144Xe + 208Pb, and 132Sn + 208Pb are investigated within the framework of the dinuclear system (DNS model. The influence of neutron excess of projectile on production cross sections of target-like products is studied through the reactions 136,144Xe + 208Pb. We find that the radioactive projectile 144Xe with much larger neutron excess is favorable to produce neutron-rich nuclei with charge number less than the target rather than produce transtarget nuclei. The incident energy dependence of yield distributions of fragments in the reaction 132Sn + 208Pb are also studied. The production cross sections of neutron-rich nuclei with Z=72–77 are predicted in the reactions 136–144Xe + 208Pb and 132Sn + 208Pb. It is noticed that the production cross sections of unknown neutron-rich nuclei in the reaction 144Xe + 208Pb are at least two orders of magnitude larger than those in the reaction 136Xe + 208Pb. The radioactive beam induced transfer reactions 139,144Xe + 208Pb, considering beam intensities proposed in SPIRAL2 (Production System of Radioactive Ion and Acceleration On-Line project as well, for production of neutron-rich nuclei around the N=126 shell closure are investigated for the first time. It is found that, in comparison to the stable beam 136Xe, the radioactive beam 144Xe shows great advantages for producing neutron-rich nuclei with N=126 and the advantages get more obvious for producing nuclei with less charge number.

Radiography and tomography using fission neutrons at FRM-II

International Nuclear Information System (INIS)

Buecherl, T.; Lierse von Gostomski, Ch.

2004-01-01

Fission neutrons offer complementary information in radiography and tomography compared to the well established techniques using X-rays, gamma-rays, thermal or cold neutrons. They penetrate thick layers of high density materials with only little attenuation, while for light, specially for hydrogen containing materials, their attenuation is high. In the past, fast neutrons for NDT (non-destructive testing) were only available at accelerator driven systems. These high energy neutrons have to be moderated to achieve acceptable detection efficiencies thus drastically reducing the available neutron intensities and either resulting in a high beam divergence or in additional losses in neutron intensities due to beam collimation. The recently installed neutron computerized tomography and radiography system NECTAR at the Forschungsreaktor Muenchen-II (FRM-II) overcomes these disadvantages by using fission neutrons of about 1.7 MeV mean energy created in two converter plates set-up of highly enriched uranium. The beam quality, i.e. the neutron divergence can be adapted to the object to be measured by using different collimators, resulting in L/D-values up to 300. The available neutron beam intensity at the measuring position is up to 1.7E+08 cm -2 s -1 for a maximum beam area of 40 cm x 40 cm. For conventional imaging a two-dimensional detector system based on a CCD-camera is used, other more specialised systems are available. (author)

Radiography and tomography using fission neutrons at FRM-II

Energy Technology Data Exchange (ETDEWEB)

Buecherl, T.; Lierse von Gostomski, Ch. [Inst. fuer Radiochemie, TU-Muenchen, Garching (Germany)

2004-07-01

Fission neutrons offer complementary information in radiography and tomography compared to the well established techniques using X-rays, gamma-rays, thermal or cold neutrons. They penetrate thick layers of high density materials with only little attenuation, while for light, specially for hydrogen containing materials, their attenuation is high. In the past, fast neutrons for NDT (non-destructive testing) were only available at accelerator driven systems. These high energy neutrons have to be moderated to achieve acceptable detection efficiencies thus drastically reducing the available neutron intensities and either resulting in a high beam divergence or in additional losses in neutron intensities due to beam collimation. The recently installed neutron computerized tomography and radiography system NECTAR at the Forschungsreaktor Muenchen-II (FRM-II) overcomes these disadvantages by using fission neutrons of about 1.7 MeV mean energy created in two converter plates set-up of highly enriched uranium. The beam quality, i.e. the neutron divergence can be adapted to the object to be measured by using different collimators, resulting in L/D-values up to 300. The available neutron beam intensity at the measuring position is up to 1.7E+08 cm{sup -2} s{sup -1} for a maximum beam area of 40 cm x 40 cm. For conventional imaging a two-dimensional detector system based on a CCD-camera is used, other more specialised systems are available. (author)

Long-term behaviour of radioactive nuclides in the environment

International Nuclear Information System (INIS)

Brechignac, F.; Moberg, L.; Suomela, M.

1999-01-01

Report of recent advances in Europe, regarding the long-term development of radioactive nuclides in the environment. The corresponding scientific findings from three projects - Peace, Landscape and Epora (involving 18 European laboratories) - have been collected together. These projects were managed by the IPSN for the European Commission (DG XII) in the framework of the programme 'Surete de la fission nucleaire' (Nuclear fission safety programme). (author)

Development of radioactivity estimation system considering radioactive nuclide movement

International Nuclear Information System (INIS)

Fukumura, Nobuo; Miyamoto, Yoshiaki

2010-01-01

A radioactivity estimation system considering radioactive nuclide movement is developed to integrate the established codes and the code system for decommissioning of sodium cooled fast reactor (FBR). The former are the codes for estimation of radioactivity movement in sodium coolant of fast reactor which are named SAFFIRE, PSYCHE and TTT. The latter code system is to estimate neutron irradiation activity (COSMARD-RRADO). It is paid special attention to keep the consistency of input data used among these codes and also the simplification of their interface. A new function is added to the estimation system, to estimate minor FP inventory caused by the fission of impurities contained in the coolant and slight fuel material attached on the fuel cladding. To check the evaluation system, the system is applied with radioactivity data of the preceding FBR such as BN-350, JOYO and Monju. Agreement between the analysis results and the measurement is well satisfactory. The uncertainty of the code system is within several tens per cent for the activation of primary coolant (Na-22) and factor of 2-4 for the estimation of radioactivity inventory in sodium coolant. (author)

Characterization of the solid radioactive waste From Cernavoda NPP

International Nuclear Information System (INIS)

Iordache, M.; Laotaru, V.

2005-01-01

Full text: During the operation of a nuclear plant significant quantities of radioactive waste result that have a very large diversity. At Cernavoda NPP large amounts of wastes are either non-radioactive wastes or radioactive wastes, each of these being managed completely different from which other. For a CANDU type reactor, the appearance of radioactive wastes is due to contamination with the following types of radioactive substances: - fission products resulting from nuclear fuel burning; - activated products from materials composing the technological systems; - activated products in process fluids. Radioactive wastes can be in solid, liquid or gas form. At Cernavoda NPP the solid wastes represent about 70% of the waste volume which is produced during plant operation and as a consequence of maintenance and decontamination operations. The most important types of solid wastes that are obtained and then handled, processed (if necessary) and temporarily stored are: solid low-level radioactive wastes (classified as compactible and non-compactible), solid medium radioactive wastes, spent resins, used filters and filter cartridges. The liquid radioactive waste class includes organic liquids (used oil, scintillator liquids and used solvents) and aqueous wastes resulting from process system operating, from decontamination and maintenance operations. Radioactive gas wastes occur subsequently to the fission process inside the fuel elements as well as due to the neutron activation of process fluids in the reactor systems. As result of plant operation, iodine, noble gases, tritium and radioactive particles occur and are passed toward the ventilation stack in a controlled manner so that environmental release of radioactive materials with concentrations exceeding the maximum permissible level could not occur. (authors)

Investigations concerning the source term for the emission of fission products and transuranic elements from the highly radioactive waste in the temperature region between 200 and 11000C

International Nuclear Information System (INIS)

Baumgartner, F.; Krebs, K.; Merte, B.

1984-04-01

Starting point of these investigations was the research report 290 of the former Institute for Reactor Safety, Cologne. The largely incorrect assumptions made in the chemical statement led to high radioactive doses not only for the closer, but also for the further surroundings of a reprocessing plant in case that the cooling system of the fuel element storage or the storage tank for the highly radioactive waste (HAW) should become inoperative for an extended period of time. However, as a result of this temperature region which we used in our experiments, the investigations concerning the source term of the HAW between 1100 and 1200 0 C became interesting again, because a glass melt of about 1100 0 C is used during the PAMELA-process for the vitrification of the HAW. The aqueous HAW-solution is thereby poured onto a hot glass melt. The solution thereby dries up, the HAW-salt is calcined and finally sinks into the glass melt. From today's point of view an investigation concerning the source term of the fission products and transuranic elements from the HAW at 1100 0 C therefore provides information regarding the fission product- and transuranic element volatilization within the melting furnace during the vitrification process. The results may now therefore also be considered a contribution for the layout of the off-gas purification system during the PAMELA-process

Development of solid water-equivalent radioactive certified reference materials

International Nuclear Information System (INIS)

Finke, E.; Greupner, H.; Groche, K.; Rittwag, R.; Geske, G.

1991-01-01

This paper presents a brief description of the development of solid water-equivalent beta volume radioactive certified reference materials. These certified reference materials were prepared for the beta fission nuclides 90 Sr/ 90 Y, 137 Cs, 147 Pm and 204 Tl. Comparative measurements of liquid and solid water-equivalent beta volume radioactive certified reference materials are discussed. (author)

Absorption by plants of unseparated fission products derived from the hydrogen bomb detonated in the spring of 1954 at Bikini Atoll

Energy Technology Data Exchange (ETDEWEB)

Yatazawa, M; Ishihara, T

1955-01-01

In a radiochemical survey on the contamination of white clover grown in a field, sample plants were obtained from the same grass land at 3 different times. The ash of each sample was analyzed. It was concluded that radioactive alkaline earths, especially /sup 89/Sr and /sup 90/Sr were selectively accumulated in plants. The selective absorption of Bikini ash by rice plants was also studied. Noncontaminated rice plants were cultivated in the radioactive solution produced from Bikini ash for 20 days. Then the absorption by plants of radioactive elements was examined by chromatographic exchange. From the elution curve and ratio of radioactivity of each separation group, it has become clear that rice plants accumulated larger parts of fission products in their roots and selectively absorbed and translocated radioactive alkaline earths in their shoots even if the absorption ratio of Bikini fission products was comparatively small.

Study on decay of rare earth nuclei produced by fission

Energy Technology Data Exchange (ETDEWEB)

Kawade, Kiyoshi; Yamamoto, Hiroshi; Shibata, Michihiro; Asai, Masato [Nagoya Univ. (Japan); Tsukada, Kazuaki; Osa, Akihiko; Shinohara, Nobuo; Iimura, Hideki

1996-01-01

JAERI-ISOL utilizes charge particle induced fission by proton and heavy proton produced by the tandem type accelerator (JAERI). To study the decay mechanism and nuclei structure of neutron and excess nuclei produced by actinoid fission, JAERI-ISOL was improved by developing the multilayer target tank. So that, the intensity of mass separated ion beam increased enough to use. New 76.6 KeV {gamma}-ray with about 10s of half life was found in the preliminary experiment. (S.Y.)

High-Level Radioactive Waste.

Science.gov (United States)

Hayden, Howard C.

1995-01-01

Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

14. Euro summer school on exotic beams

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-01

This school is intended for thesis students and young post-docs working in areas related to radioactive beams. It consists of several lecture courses given by specialists in their field, starting from a basic level. This document gathers only the slides of the following presentations: 1) clusters in nuclei, 2) the production of radioactive ion beams - in-flight methods, 3) ab-initio calculations for light nuclei, 4) the production of radioactive ion beams - ISOL methods, 5) neutrons for science, and 6) the production of radioactive ion beams - charge breeding.

14. Euro summer school on exotic beams

International Nuclear Information System (INIS)

2007-01-01

This school is intended for thesis students and young post-docs working in areas related to radioactive beams. It consists of several lecture courses given by specialists in their field, starting from a basic level. This document gathers only the slides of the following presentations: 1) clusters in nuclei, 2) the production of radioactive ion beams - in-flight methods, 3) ab-initio calculations for light nuclei, 4) the production of radioactive ion beams - ISOL methods, 5) neutrons for science, and 6) the production of radioactive ion beams - charge breeding

Proton-fission for the accelerator production of Mo-99

International Nuclear Information System (INIS)

Lagunas-Solar, M.C.; Jungerman, J.A.; Castaneda, C.M.

1993-01-01

The production of Mo-99 (66.0 h) via de U-238(p,f) Mo-99 fission reaction is proposed as a non-reactor source of this essential precursor of 6.6-h Tc-99m, an isotope of wide use of diagnostic nuclear medicine applications. Measurements of the total excitation function for the U-238(p,f) reaction indicated a maximum and fairly constant cross section of 1.4 barns at > 30 MeV. Combining the advances of high-current (mA) H-accelerators with dual beam (dual target) operation, and assuming a 5% fission yield, estimates of Mo-99 reaches 5 to 14 Ci/h at 1 mA. The proton fission production of Mo-99 appears to more advantageous than the reactor produced via evaporation neutron-induced fission. An accelerator method could allow securing ample supply of Mo-99 independently of the current scarce reactor operation, while also simplifying the associated waste management problems as well as some of the environmental concerns

216-S-1 and S-2 mixed-fission-product crib-characterization study

Energy Technology Data Exchange (ETDEWEB)

Van Luik, A. E.; Smith, R. M.

1982-03-01

The 216-S-1 and 2 crib is an underground structure that was used for the disposal of radioactively contaminated liquid waste at the Hanford Site. The crib received acidic, intermediate level, mixed fission-product waste solutions from 1952 to 1956. The 1980 status of radioactive contaminants in the sediment beneath the crib was investigated. The results indicate that the radionuclide distributions are stable, with no evidence of significant translocations found since the late 1960's.

216-S-1 and S-2 mixed-fission-product crib-characterization study

International Nuclear Information System (INIS)

Van Luik, A.E.; Smith, R.M.

1982-03-01

The 216-S-1 and 2 crib is an underground structure that was used for the disposal of radioactively contaminated liquid waste at the Hanford Site. The crib received acidic, intermediate level, mixed fission-product waste solutions from 1952 to 1956. The 1980 status of radioactive contaminants in the sediment beneath the crib was investigated. The results indicate that the radionuclide distributions are stable, with no evidence of significant translocations found since the late 1960's

Radioactive waste management

International Nuclear Information System (INIS)

Blomek, D.

1980-01-01

The prospects of nuclear power development in the USA up to 2000 and the problems of the fuel cycle high-level radioactive waste processing and storage are considered. The problems of liquid and solidified radioactive waste transportation and their disposal in salt deposits and other geologic formations are discussed. It is pointed out that the main part of the high-level radioactive wastes are produced at spent fuel reprocessing plants in the form of complex aqueous mixtures. These mixtures contain the decay products of about 35 isotopes which are the nuclear fuel fission products, about 18 actinides and their daughter products as well as corrosion products of fuel cans and structural materials and chemical reagents added in the process of fuel reprocessing. The high-level radioactive waste management includes the liquid waste cooling which is necessary for the short and middle living isotope decay, separation of some most dangerous components from the waste mixture, waste solidification, their storage and disposal. The conclusion is drawn that the seccessful solution of the high-level radioactive waste management problem will permit to solve the problem of the fuel cycle radioactive waste management as a whole. The salt deposits, shales and clays are the most suitable for radioactive waste disposal [ru

Mass resolved angular distribution of fission products in 20Ne + 232Th reaction

International Nuclear Information System (INIS)

Tripathi, R.; Sodaye, S.; Sudarshan, K.; Kumar, Amit; Guin, R.

2011-01-01

Mass resolved angular distribution of fission products was measured in 20 Ne + 232 Th reaction at beam energy of 120 MeV. A preliminary analysis of the angular distribution data of fission products shows higher average anisotropy compared to that calculated using statistical theory. A signature of rise in anisotropy near symmetry, as reported in earlier studies in literature, is also seen. Further study is in progress to get more detailed information about the contribution from non-compound nucleus fission and dependence of angular anisotropy on asymmetry of mass division

Studies of the Fission Integrals of U-{sup 235} and Pu-{sup 239} with Cadmium and Filters

Energy Technology Data Exchange (ETDEWEB)

Hellstrand, E

1965-04-15

The resonance fissions in U{sup 235} and Pu{sup 239} have been studied using cadmium and boron filters. Fission chambers were used as detectors and the experiments were performed in beam geometry. The neutron energy distribution in the beams transmitted through the different filters was determined with a fast chopper. From the cadmium filter, measurements the fission resonance integrals were determined. The values obtained were 278{+-}9 b for U{sup 235} and 301{+-}10 b for Pu{sup 239}; 0.5 eV < E < 1 MeV. Complementary Pu{sup 239} measurements were made in which the fission events were detected from the fission product activity in irradiated foils. Contrary to what has been reported elsewhere the value of the Pu{sup 239} resonance integral, found in this way, agreed well with that obtained from the fission chamber measurement. The experiments with the boron filters yielded results which, for the thin filter, agreed well with those calculated from the cross section data given in the Karlsruhe compilation. The discrepancy was larger for the thick filter but the values did not disagree outside the common limits of error.

High-spin nuclear structure studies with radioactive ion beams

International Nuclear Information System (INIS)

Baktash, C.

1992-01-01

Two important developments in the sixties, namely the advent of heavy-ion accelerators and fabrication of Ge detectors, opened the way for the experimental studies of nuclear properties at high angular momentum. Addition of a new degree of freedom, namely spin, made it possible to observe such fascinating phenomena as occurrences and coexistence of a variety of novel shapes, rise, fall and occasionally rebirth of nuclear collectivity, and disappearance of pairing correlations. Today, with the promise of development of radioactive ion beams (RIB) and construction of the third-generation Ge-detection systems (GAMMASPHERE and EUROBALL), nuclear physicists are poised to explore new and equally fascinating phenomena that have been hitherto inaccessible. With the addition of yet another dimension, namely the isospin, they will be able to observe and verify predictions for exotic shapes as varied as rigid triaxiality, hyperdeformation and triaxial-octupole shapes, or to investigate the T=O pairing correlations. In this paper, the author reviews, separately for neutron-deficient and neutron-rich nuclei, these and a few other new high-spin physics opportunities that may be realized with RIB. Following this discussion, a list of the beam species, intensities and energies that are needed to fulfill these goals is presented. The paper concludes with a description of the experimental techniques and instrumentations that are required for these studies

Fission and the discovery of isotopes

International Nuclear Information System (INIS)

Thoennessen, M.

2014-01-01

The discovery of new isotopes requires new developments in accelerator and detector technology. The new RI Beam Factory at RIKEN and the future projects FAIR at GSI and FRIB at MSU promise to expand the nuclear horizon even further. In the talk a short history of the role that fission played in the discovery of isotopes will be presented and future perspectives will be discussed

JEFF 3.1.2 - Joint evaluated nuclear data library for fission and fusion applications - February 2012 (DVD)

International Nuclear Information System (INIS)

2012-02-01

The Joint Evaluated Fission and Fusion File (JEFF) project is a collaboration between NEA Data Bank member countries. The JEFF library combines the efforts of the JEFF and EFF/EAF Working Groups to produce a common sets of evaluated nuclear data, mainly for fission and fusion applications. The JEFF-3.1.2 version, released in February 2012, contains a number of different data types, including neutron and proton interaction data, radioactive decay data, fission yields, and thermal scattering law data. Currently, JEFF-3.1.2 data are available in ENDF-6 format (neutron library) from the Web. This new release is an update from JEFF-3.1.1 which concerns 115 material files from the general purpose incident neutron library which have been modified since JEFF-3.1.1. Modifications include: Hf isotopes: 6 new Hf evaluations have replaced previous ones; Gamma production data from neutron capture (MF=6 MT=102) has been added to 89 fission products (FP) evaluations; 47 of these FP have been replaced by ENDF-B/VII.0 evaluations, with gamma data added in this release. Corrections from JEFF-Beta feedback have been incorporated for 15 materials. Corrections that solve NJOY covariance processing problems and JANIS warnings have been made to 6 files. This DVD contains: - General purpose incident neutron data in ENDF-6 and ACE formats; - Activation data; - Thermal scattering data; - Incident proton data; - Radioactive decay data; - Neutron-induced fission yields data; - Spontaneous fission yields data

SOFIA: An innovative setup to measure complete isotopic yield of fission fragments

Directory of Open Access Journals (Sweden)

Pellereau E.

2013-12-01

Full Text Available We performed an experiment dedicated to the accurate isotopic yield measurement of fission fragments over the whole range. SOFIA exploits the inverse kinematics technique: using heavy ion beams at relativistic energies, fission is induced by Coulomb excitation in a high-Z target. The fragments are emitted forward and both of them are identified in charge and mass. The setup will be presented, as well as preliminary spectra.

A new fission-fragment detector to complement the CACTUS-SiRi setup at the Oslo Cyclotron Laboratory

Energy Technology Data Exchange (ETDEWEB)

Tornyi, T.G., E-mail: tornyitom@atomki.hu [Department of Physics, University of Oslo (Norway); Institute of Nuclear Research of the Hungarian Academy of Sciences (MTA Atomki), Debrecen (Hungary); Görgen, A.; Guttormsen, M.; Larsen, A.C.; Siem, S. [Department of Physics, University of Oslo (Norway); Krasznahorkay, A. [Institute of Nuclear Research of the Hungarian Academy of Sciences (MTA Atomki), Debrecen (Hungary); Csige, L. [Institute of Nuclear Research of the Hungarian Academy of Sciences (MTA Atomki), Debrecen (Hungary); Max-Planck-Institute for Quantum Optics, D-85748 Garching (Germany)

2014-02-21

An array of Parallel Plate Avalanche Counters (PPAC) for the detection of heavy ions has been developed. The new device, NIFF (Nuclear Instrument for Fission Fragments), consists of four individual detectors and covers 60% of 2π. It was designed to be used in conjunction with the SiRi array of ΔE−E silicon telescopes for light charged particles and fits into the CACTUS array of 28 large-volume NaI scintillation detectors at the Oslo Cyclotron Laboratory. The low-pressure gas-filled PPACs are sensitive for the detection of fission fragments, but are insensitive to scattered beam particles of light ions or light-ion ejectiles. The PPAC detectors of NIFF have good time resolution and can be used either to select or to veto fission events in in-beam experiments with light-ion beams and actinide targets. The powerful combination of SiRi, CACTUS, and NIFF provides new research opportunities for the study of nuclear structure and nuclear reactions in the actinide region. The new setup is particularly well suited to study the competition of fission and γ decay as a function of excitation energy.

Status of the SPES project, a new tool for fundamental and apply science studies with exotic ion beams at LNL

Energy Technology Data Exchange (ETDEWEB)

Napoli, D. R., E-mail: napoli@lnl.infn.it; Andrighetto, A.; Antonini, P.; Benini, D.; Bermudez, J.; Bisoffi, G.; Boratto, E.; Bortolato, D.; Calderolla, M.; Calore, A.; Campo, D.; Carturan, S.; Cinausero, M.; Comunian, M.; Corradetti, S.; De Angelis, G.; De Ruvo, P. L.; Esposito, J.; Ferrari, L.; Galatá, A. [INFN - Laboratori Nazionali di Legnaro, Viale dell’Università 2, I-35020 Legnaro (PD) (Italy); and others

2016-07-07

SPES, a new accelerator facility for both the production of exotic ion beams and radio-pharmaceuticals, is presently being installed at the Laboratori Nazionali di Legnaro in Italy (LNL). The new cyclotron, which will provide high intensity proton beams for the production of the rare isotopes, has been installed and is now in the commissioning phase. We present here the status of the part of the project devoted to the production and acceleration of fission fragments created in the interaction of an intense proton beam on a production target of UCx. The expected SPES radioactive beams intensities, their quality and their maximum energies (up to 11 MeV/A for A=130) will permit to perform forefront research in nuclear structure and nuclear dynamics far from the stability valley. Another low energy section of the facility is foreseen for new and challenging research, both in the nuclear physics and in the material science frameworks.

Development of solid water-equivalent radioactive certified reference materials

Energy Technology Data Exchange (ETDEWEB)

Finke, E.; Greupner, H.; Groche, K.; Rittwag, R. (Office for Standardization, Metrology and Quality Control (ASMW), Berlin (Germany, F.R.)); Geske, G. (Jena Univ. (Germany, F.R.))

1991-01-01

This paper presents a brief description of the development of solid water-equivalent beta volume radioactive certified reference materials. These certified reference materials were prepared for the beta fission nuclides {sup 90}Sr/{sup 90}Y, {sup 137}Cs, {sup 147}Pm and {sup 204}Tl. Comparative measurements of liquid and solid water-equivalent beta volume radioactive certified reference materials are discussed. (author).

Fission 2009 4. International Workshop on Nuclear Fission and Fission Product Spectroscopy - Compilation of slides

International Nuclear Information System (INIS)

2009-01-01

This conference is dedicated to the last achievements in experimental and theoretical aspects of the nuclear fission process. The topics include: mass, charge and energy distribution, dynamical aspect of the fission process, nuclear data evaluation, quasi-fission and fission lifetime in super heavy elements, fission fragment spectroscopy, cross-section and fission barrier, and neutron and gamma emission. This document gathers the program of the conference and the slides of the presentations

Nuclear fission and neutron-induced fission cross-sections

Energy Technology Data Exchange (ETDEWEB)

James, G.D.; Lynn, J.E.; Michaudon, A.; Rowlands, J.; de Saussure, G.

1981-01-01

A general presentation of current knowledge of the fission process is given with emphasis on the low energy fission of actinide nuclei and neutron induced fission. The need for and the required accuracy of fission cross section data in nuclear energy programs are discussed. A summary is given of the steps involved in fission cross section measurement and the range of available techniques. Methods of fission detection are described with emphasis on energy dependent changed and detector efficiency. Examples of cross section measurements are given and data reduction is discussed. The calculation of fission cross sections is discussed and relevant nuclear theory including the formation and decay of compound nuclei and energy level density is introduced. A description of a practical computation of fission cross sections is given.

Radioactive waste management and regulation

International Nuclear Information System (INIS)

Willrich, M.; Lester, R.K.; Greenberg, S.C.; Mitchell, H.C.; Walker, D.A.

1977-01-01

Purpose of this book is to assist in developing public policy and institutions for the safe management of radioactive waste, currently and long term. Both high-level waste and low-level waste containing transuranium elements are covered. The following conclusions are drawn: the safe management of post-fission radioactive waste is already a present necessity and an irreversible long-term commitment; the basic goals of U.S. radioactive waste policy are unclear; the existing organization for radioactive waste management is likely to be unworkable if left unchanged; and the existing framework for radioactive waste regulation is likely to be ineffective if left unchanged. The following recommendations are made: a national Radioactive Waste Authority should be established as a federally chartered public corporation; with NRC as the primary agency, a comprehensive regulatory framework should be established to assure the safety of all radioactive waste management operations under U.S. jurisdiction or control; ERDA should continue to have primary government responsibility for R and D and demonstration of radioactive waste technology; and the U.S. government should propose that an international Radioactive Waste Commission be established under the IAEA

Fission and nuclear fragmentation of silver and bromine nuclei by photons of 1-6 GeV

International Nuclear Information System (INIS)

Pinheiro Filho, J.D.

1983-01-01

The studies of fission and fragmentation of silver and bromine nuclei by Bremsstrahlung photons of 1.6 GeV energy range are presented. The Il ford-KO nuclear emulsion submitted to Bremsstrahlung beams in Deutsches Elektronen Synchrotron (DESY) with total doses of 10'' equivalent photons, was used for nuclear fragment detection. The discrimination of fission and fragmentation events was done analysing angular distribution, range and angles between fragments. The results of fragment range distributions, angular distributions, distributions of angles between fragments, distributions of ratio between range, velocity distributions forward/backward ratio, cross sections of fission and fragmentation, nuclear fissionability and ternary fission frequency are presented and discussed. (M.C.K.)

Recent results in the study of exotic nuclei using the 'Radioactive Ion Beams in Brazil' (RIBRAS) facility

Energy Technology Data Exchange (ETDEWEB)

Lepine-Szily, A.; Lichtenthaeler, R.; Guimaraes, V.; Alcantara Nunez, J.; Benjamim, E.A.; Faria, P.N. de; Leistenschneider, E.; Gasques, L.R.; Morais, M.C.; Pampa Condori, R.; Pires, K.C.C.; Scarduelli, V.; Zamora, J.C. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica; Mendes Junior, D.R.; Morcelle, V. [Universidade Federal Fluminense (IF/UFF), Niteroi, RJ (Brazil). Inst. de Fisica; Descouvemont, P. [Universite Libre de Bruxelles (Belgium). Physique Nucleaire Theorique et Physique Matematique; Assuncao, M. [Universidade Federal de Sao Paulo (UNIFESP), Diadema, SP (Brazil); Moro, A.M. [Universidad de Sevilla (Spain). Fac. de Fisica. Dept. de Fisica Atomica, Molecular y Nuclear (FAMN); Arazi, A. [Comision Nacional de Energia Atomica (CNEA), Buenos Aires (Argentina). Lab. TANDAR; Barioni, A. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil)

2012-07-01

Full text: The 'Radioactive Ion Beams in Brasil' (RIBRAS) facility consists of two super-conducting solenoids of maxi- mum magnetic field B 6.5T, coupled to the 8UD-Pelletron tandem Accelerator installed at the University of Sao Paulo Physics Institute. It is the first radioactive beam facility of the Southern Hemisphere. The production mechanism of the radioactive ions is by transfer reactions, using {sup 9}Be, {sup 3}He, LiF and other production targets, and the forward focused reaction products are selected and focalized by the solenoids into a scattering chamber. Low energy (3-5 MeV/u) radioactive beams of {sup 6}He, {sup 8}Li, {sup 7,10}Be and {sup 8,12}B are produced currently and used to study elastic, inelastic, and transfer reactions on a variety of light, medium mass and heavy ({sup 9}Be, {sup 12}C, {sup 27}Al, {sup 51}V and {sup 120}Sn) secondary targets. The data are analyzed, using most of the time, the Sao Paulo Potential (SPP) and compared to optical model and continuum discretized coupled-channels (CDCC) calculations. The total reaction cross section as a function of energy has been extracted from the elastic scattering data and the role of breakup of weakly bound or exotic nuclei is discussed. Some examples of reactions recently studied are {sup 1}H({sup 8}Li,{sup 4}He){sup 5}He, {sup 1}H({sup 8}Li,{sup 1}H){sup 8}Li using thick (CH{sub 2}){sub n} targets to measure their excitation functions. The transfer reaction {sup 12}C({sup 8}Li,{sup 4}He){sup 16}N, leading to well defined excited states of {sup 16}N, through the transfer of {sup 4}H or the sequential decay {sup 3}H+n, is also being studied. (author)

Radioactivity in Trinitite six decades later

International Nuclear Information System (INIS)

Parekh, Pravin P.; Semkow, Thomas M.; Torres, Miguel A.; Haines, Douglas K.; Cooper, Joseph M.; Rosenberg, Peter M.; Kitto, Michael E.

2006-01-01

The first nuclear explosion test, named the Trinity test, was conducted on July 16, 1945 near Alamogordo, New Mexico. In the tremendous heat of the explosion, the radioactive debris fused with the local soil into a glassy material named Trinitite. Selected Trinitite samples from ground zero (GZ) of the test site were investigated in detail for radioactivity. The techniques used included α spectrometry, high-efficiency γ-ray spectrometry, and low-background β counting, following the radiochemistry for selected radionuclides. Specific activities were determined for fission products ( 9 Sr, 137 Cs), activation products ( 6 Co, 133 Ba, 152 Eu, 154 Eu, 238 Pu, 241 Pu), and the remnants of the nuclear fuel ( 239 Pu, 24 Pu). Additionally, specific activities of three natural radionuclides ( 4 K, 232 Th, 238 U) and their progeny were measured. The determined specific activities of radionuclides and their relationships are interpreted in the context of the fission process, chemical behavior of the elements, as well as the nuclear explosion phenomenology

Studies of pear-shaped nuclei using accelerated radioactive beams

CERN Document Server

Gaffney, L P; Scheck, M; Hayes, A B; Wenander, F; Albers, M; Bastin, B; Bauer, C; Blazhev, A; Bonig, S; Bree, N; Cederkall, J; Chupp, T; Cline, D; Cocolios, T E; Davinson, T; DeWitte, H; Diriken, J; Grahn, T; Herzan, A; Huyse, M; Jenkins, D G; Joss, D T; Kesteloot, N; Konki, J; Kowalczyk, M; Kroll, Th; Kwan, E; Lutter, R; Moschner, K; Napiorkowski, P; Pakarinen, J; Pfeiffer, M; Radeck, D; Reiter, P; Reynders, K; Rigby, S V; Robledo, L M; Rudigier, M; Sambi, S; Seidlitz, M; Siebeck, B; Stora, T; Thoele, P; Van Duppen, P; Vermeulen, M J; von Schmid, M; Voulot, D; Warr, N; Wimmer, K; Wrzosek-Lipska, K; Wu, C Y; Zielinska, M

2013-01-01

There is strong circumstantial evidence that certain heavy, unstable atomic nuclei are ‘octupole deformed’, that is, distorted into a pear shape. This contrasts with the more prevalent rugby-ball shape of nuclei with reflection-symmetric, quadrupole deformations. The elusive octupole deformed nuclei are of importance for nuclear structure theory, and also in searches for physics beyond the standard model; any measurable electric-dipole moment (a signature of the latter) is expected to be amplified in such nuclei. Here we determine electric octupole transition strengths (a direct measure of octupole correlations) for short-lived isotopes of radon and radium. Coulomb excitation experiments were performed using accelerated beams of heavy, radioactive ions. Our data on and $^{224}$Ra show clear evidence for stronger octupole deformation in the latter. The results enable discrimination between differing theoretical approaches to octupole correlations, and help to constrain suitable candidates for experimental...

The role of chemistry in the history of radioactivity (1897-1939)

International Nuclear Information System (INIS)

Adloff, J.P.

1997-01-01

Chemical research on radioactivity started in 1898. That year, Pierre and Marie Curie discovered in pitchblende polonium and radium. Rutherford and Soddy showed that radioactivity is an atomic phenomenon accompanied by transmutation of elements and established the basic laws of radioactive changes. The existence of isotopes was postulated after the discovery of many radioactive substances. Major discoveries in nuclear science, i.e. the atomic nucleus, the neutron and artificial radioactivity, were made with radiation sources elaborated bu chemists. Finally, in 1939, radiochemists on the search for transuranium elements, discovered nuclear fission. (authors)

Nuclear fission and fission-product spectroscopy: 3. International workshop on nuclear fission and fission-product spectroscopy

International Nuclear Information System (INIS)

Goutte, Heloise; Fioni, Gabriele; Faust, Herbert; Goutte, Dominique

2005-01-01

The present book contains the proceedings of the third workshop in a series of workshops previously held in Seyssins in 1994 and 1998. The meeting was jointly organized by different divisions of CEA and two major international laboratories. In the opening address, Prof. B. Bigot, the French High Commissioner for Atomic Energy, outlined France's energy policy for the next few decades. He emphasized the continuing progress of nuclear fission in both technical and economic terms, allowing it to contribute to the energy needs of the planet even more in the future than it does today. Such progress implies a very strong link between fundamental and applied research based on experimental and theoretical approaches. The workshop gathered the different nuclear communities studying the fission process, including topics as the following: - nuclear fission experiments, - spectroscopy of neutron rich nuclei, - fission data evaluation, - theoretical aspects of nuclear fission, - and innovative nuclear systems and new facilities. The scientific program was suggested by an International Advisory Committee. About 100 scientists from 13 different countries attended the conference in the friendly working atmosphere of the Castle of Cadarache in the heart of the Provence. The proceedings of the workshop were divided into 11 sections addressing the following subject matters: 1. Cross sections and resonances (5 papers); 2. Fission at higher energies - I (5 papers); 3. Fission: mass and charge yields (4 papers); 4. Light particles and cluster emission (4 papers); 5. Spectroscopy of neutron rich nuclei (5 papers); 6. Resonances, barriers, and fission times (5 papers); 7. Fragment excitation and neutron emission (4 papers); 8. Mass and energy distributions (4 papers); 9. Needs for nuclear data and new facilities - I (4 papers); 10. Angular momenta and fission at higher Energies - II (3 papers); 11. New facilities - II (2 papers). A poster session of 8 presentations completed the workshop

Modification of the fission product inventory program FISPIN

International Nuclear Information System (INIS)

Thomas, R.B.

1977-05-01

The fission product inventory program FISPIN calculates inventories of fission products, actinides and activation products, during and after irradiation in a nuclear reactor, estimates also being given for heat output and radioactive activity of the isotopes. The program has been developed further by making provision for the simulation of fuel reprocessing and in providing subroutines to make the program compatible with nuclear data in a slightly modified ENDF/B4 format. Continuous development of FISPIN over the years has however involved many program alterations and additions, and this has resulted in a generally untidy and cumbersome program. An attempt has therefore been made to improve the basic structure of the program. The subject is dealt with under the following headings: modularisation, direct access data, override facility, selective output, flowcharts, summary. (U.K.)

Studies of nuclei using radioactive beams. Progress report, May 1988--July 1989

Energy Technology Data Exchange (ETDEWEB)

Piercey, R.B.

1989-07-01

The 12 month period from May 1988 to July 1989 represents the first full year of our 18 month pilot program in nuclear structure research. In this period, research was initiated to develop a capability for radioactive secondary beams at Argonne National Laboratory using the Atlas and the new Fragment Mass Analyzer (FMA), which is currently under construction. Two major new detector facilities are currently in the final stages of design and testing. The Large-Area, Scintillator Telescope (LAST) detector is fully operational and will be shipped to Argonne National Laboratory in August for fit-tests and in-beam calibrations. The first segments of a new sixteen-segment neutron multiplicity detector have been built and tested. The remaining segments are currently being constructed. Research was continued in the areas of (1) Coulomb excitation studies of rare earth and actinide nuclei; (2) In-beam, gamma-ray spectroscopy of nuclei in the mass 100 region, and (3) Advanced detector design. Several journal articles and abstracts were published or submitted for publication in the reporting period, and others are currently in preparation. Three graduate students participated in the program, one from the University of Florida and two from the Royal Institute of Technology, Stockholm, Sweden.

Direct Reaction Experimental Studies with Beams of Radioactive Tin Ions

Energy Technology Data Exchange (ETDEWEB)

Jones, K. L. [University of Tennessee, Knoxville (UTK); Ahn, S.H. [University of Tennessee, Knoxville (UTK); Allmond, James M [ORNL; Ayres, A. [University of Tennessee, Knoxville (UTK); Bardayan, Daniel W [ORNL; Baugher, T. [Michigan State University, East Lansing; Bazin, D. [Michigan State University, National Superconducting Cyclotron Laboratory (NSCL); Beene, James R [ORNL; Berryman, J. S. [Michigan State University, East Lansing; Bey, A. [University of Tennessee, Knoxville (UTK); Bingham, C. R. [University of Tennessee, Knoxville (UTK); Cartegni, L. [University of Tennessee, Knoxville (UTK); Chae, K. Y. [University of Tennessee, Knoxville (UTK)/Sungkyunkwan University, Korea; Cizewski, J. A. [Rutgers University; Gade, A. [Michigan State University, National Superconducting Cyclotron Laboratory (NSCL); Galindo-Uribarri, Alfredo {nmn} [ORNL; Garcia-Ruiz, R.F. [Instituut voor Kernen Stralingsfysica, KU Leuven, B-3001, Leuven, Belgium; Grzywacz, Robert Kazimierz [ORNL; Howard, Meredith E [ORNL; Kozub, R. L. [Tennessee Technological University (TTU); Liang, J Felix [ORNL; Manning, Brett M [ORNL; Matos, M. [Louisiana State University; McDaniel, S. [Michigan State University, East Lansing; Miller, D. [University of Tennessee, Knoxville (UTK); Nesaraja, Caroline D [ORNL; O' Malley, Patrick [Rutgers University; Padgett, S [University of Tennessee, Knoxville (UTK); Padilla-Rodal, Elizabeth [Universidad Nacional Autonoma de Mexico (UNAM); Pain, Steven D [ORNL; Pittman, S. T. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Radford, David C [ORNL; Ratkiewicz, Andrew J [ORNL; Schmitt, Kyle [ORNL; Smith, Michael Scott [ORNL; Stracener, Daniel W [ORNL; Stroberg, S. [Michigan State University, East Lansing; Tostevin, Jeffrey A [ORNL; Varner Jr, Robert L [ORNL; Weisshaar, D. [Michigan State University, East Lansing; Wimmer, K. [Michigan State University, National Superconducting Cyclotron Laboratory (NSCL)/Central Michigan University; Winkler, R. [Michigan State University, East Lansing

2015-01-01

The tin chain of isotopes provides a unique region in which to investigate the evolution of single-particle structure, spreading from N = 50 at Sn-100, through 10 stable isotopes and the N = 82 shell closure at Sn-132 out into the r-process path. Direct reactions performed on radioactive ion beams are sensitive spectroscopic tools for studying exotic nuclei. Here we present one experiment knocking out neutrons from tin isotopes that are already neutron deficient and two reactions that add a neutron to neutron-rich Sn-130. Both techniques rely on selective particle identification and the measurement of gamma rays in coincidence with charged ions. We present the goals of the two experiments and the particle identification for the channels of interest. The final results will be presented in future publications.

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.

Trapping radioactive ions

International Nuclear Information System (INIS)

Kluge, H.-J.; Blaum, K.

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

Method of processing liquid waste containing fission product

International Nuclear Information System (INIS)

Funabashi, Kiyomi; Kawamura, Fumio; Matsuda, Masami; Komori, Itaru; Miura, Eiichi.

1988-01-01

Purpose: To prepare solidification products of low surface dose by removing cesium which is main radioactive nuclides from re-processing plants. Method: Liquid wastes containing a great amount of fission products are generated accompanying the reprocessing for spent nuclear fuels. After pH adjustment, the liquid wastes are sent to a concentrator to concentrate the dissolved ingredients. The concentrated liquid wastes are pumped to an adsorption tower in which radioactive cesium contributing much to the surface dose is removed. Then, the liquid wastes are sent by way of a surge tank to a mixing tank, in which they are mixed under stirring with solidifying agents such as cements. Then, the mixture is filled in a drum-can and solidified. According to this invention, since radioactive cesium is removed before solidification, it is possible to prepare solidification products at low surface dose and facilitate the handling of the solidification products. (Horiuchi, T.)

Induced radioactivity of a GSO scintillator by secondary fragments in carbon ion therapy and its effects on in-beam OpenPET imaging.

Science.gov (United States)

Hirano, Yoshiyuki; Nitta, Munetaka; Nishikido, Fumihiko; Yoshida, Eiji; Inadama, Naoko; Yamaya, Taiga

2016-07-07

The accumulation of induced radioactivity within in-beam PET scanner scintillators is of concern for its long-term clinical usage in particle therapy. To estimate the effects on OpenPET which we are developing for in-beam PET based on GSOZ (Zi doped Gd2SiO5), we measured the induced radioactivity of GSO activated by secondary fragments in a water phantom irradiation by a (12)C beam with an energy of 290 MeV u(-1). Radioisotopes of Na, Ce, Eu, Gd, Nd, Pm and Tb including positron emitters were observed in the gamma ray spectra of the activated GSO with a high purity Ge detector and their absolute radioactivities were calculated. We used the Monte Carlo simulation platform, Geant4 in which the observed radioactivity was assigned to the scintillators of a precisely reproduced OpenPET and the single and coincidence rates immediately after one treatment and after one-year usage were estimated for the most severe conditions. Comparing the highest coincidence rate originating from the activated scintillators (background) and the expected coincidence rate from an imaging object (signal), we determined the expected signal-to-noise ratio to be more than 7 within 3 min and more than 10 within 1 min from the scan start time. We concluded the effects of scintillator activation and their accumulation on the OpenPET imaging were small and clinical long-term usage of the OpenPET was feasible.

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)

Selection of RIB targets using ion implantation at the Holifield radioactive ion beam facility

International Nuclear Information System (INIS)

Alton, G.D.; Dellwo, J.

1995-01-01

Among several major challenges posed by generating and accelerating adequate intensities of RIBs, selection of the most appropriate target material is perhaps the most difficult because of the requisite fast and selective thermal release of minute amounts of the short-lived product atoms from the ISOL target in the presence of bulk amounts of target material. Experimental studies are under way at the Oak Ridge National Laboratory (ORNL) which are designed to measure the time evolution of implanted elements diffused from refractory target materials which are candidates for forming radioactive ion beams (RIBs) at the Holifield Radioactive Ion Beam Facility (HRIBF). The diffusion coefficients are derived by comparing experimental data with numerical solutions to a one-dimensional form of Fick's second law for ion implanted distributions. In this report, we describe the experimental arrangement, experimental procedures, and provide time release data and diffusion coefficients for releasing ion implanted 37 Cl from Zr 5 Si 3 and 75 As, 79 Br, and 78 Se from Zr 5 Ge 3 and estimates of the diffusion coefficients for 35 Cl, 63 Cu, 65 Cu, 69 Ga and 71 Ga diffused from BN; 35 Cl, 63 Cu, 65 Cu, 69 Ga, 75 As, and 78 Se diffused from C; 35 Cl, 68 Cu, 69 Ga, 75 As, and 78 Se diffused from Ta

Delayed fission

Energy Technology Data Exchange (ETDEWEB)

Hatsukawa, Yuichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment