Design of an electron-accelerator-driven compact neutron source for non-destructive assay

NASA Astrophysics Data System (ADS)

Murata, A.; Ikeda, S.; Hayashizaki, N.

2017-09-01

The threat of nuclear and radiological terrorism remains one of the greatest challenges to international security, and the threat is constantly evolving. In order to prevent nuclear terrorism, it is important to avoid unlawful import of nuclear materials, such as uranium and plutonium. Development of technologies for non-destructive measurement, detection and recognition of nuclear materials is essential for control at national borders. At Tokyo Institute of Technology, a compact neutron source system driven by an electron-accelerator has been designed for non-destructive assay (NDA). This system is composed of a combination of an S-band (2.856 GHz) RF-gun, a tungsten target to produce photons by bremsstrahlung, a beryllium target, which is suitable for use in generating neutrons because of the low threshold energy of photonuclear reactions, and a moderator to thermalize the fast neutrons. The advantage of this system can accelerate a short pulse beam with a pulse width less than 1 μs which is difficult to produce by neutron generators. The amounts of photons and neutron produced by electron beams were simulated using the Monte Carlo simulation code PHITS 2.82. When the RF-gun is operated with an average electron beam current of 0.1 mA, it is expected that the neutron intensities are 1.19 × 109 n/s and 9.94 × 109 n/s for incident electron beam energies of 5 MeV and 10 MeV, respectively.

A Personal Perspective on Triangle Universities Nuclear Laboratory Development

NASA Astrophysics Data System (ADS)

Clegg, Thomas B.

2011-10-01

Nuclear physics research in NC began seriously in 1950 when Henry Newson and his colleagues at Duke attracted support for a 4 MeV Van de Graaff accelerator with which they grew their doctoral training program. The lab's scientific achievements also grew, including the discovery in 1966 of fine structure of nuclear analog states. By then UNC and NC State had attracted Eugen Merzbacher and Worth Seagondollar who, with Newson, brought more faculty to work at an enlarged three-university, cooperative lab. Launched at Duke in 1967 with a 30 MeV Cyclograff accelerator, and subsequently equipped with a polarized H and D ion source and polarized H and ^3He targets, an extensive program in light-ion and neutron physics ensued. Faculty interest in electromagnetic interactions led to development since 2001 of TUNL's HIγS facility to produce intense 1-100 MeV polarized photon beams with small energy spread. Photonuclear reaction studies there today are producing results of unmatched quality. These 60 years of nuclear physics research have produced ˜250 doctoral graduates, many of whom have gone on to very distinguished careers. A personal perspective on these activities will be presented.

Electrical Engineering in Los Alamos Neutron Science Center Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silva, Michael James

The field of electrical engineering plays a significant role in particle accelerator design and operations. Los Alamos National Laboratories LANSCE facility utilizes the electrical energy concepts of power distribution, plasma generation, radio frequency energy, electrostatic acceleration, signals and diagnostics. The culmination of these fields produces a machine of incredible potential with uses such as isotope production, neutron spallation, neutron imaging and particle analysis. The key isotope produced in LANSCE isotope production facility is Strontium-82 which is utilized for medical uses such as cancer treatment and positron emission tomography also known as PET scans. Neutron spallation is one of the verymore » few methods used to produce neutrons for scientific research the other methods are natural decay of transuranic elements from nuclear reactors. Accelerator produce neutrons by accelerating charged particles into neutron dense elements such as tungsten imparting a neutral particle with kinetic energy, this has the benefit of producing a large number of neutrons as well as minimizing the waste generated. Utilizing the accelerator scientist can gain an understanding of how various particles behave and interact with matter to better understand the natural laws of physics and the universe around us.« less

Activation assessment of the soil around the ESS accelerator tunnel

NASA Astrophysics Data System (ADS)

Rakhno, I. L.; Mokhov, N. V.; Tropin, I. S.; Ene, D.

2018-06-01

Activation of the soil surrounding the ESS accelerator tunnel calculated by the MARS15 code is presented. A detailed composition of the soil, that comprises about 30 chemical elements, is considered. Spatial distributions of the produced activity are provided in both transverse and longitudinal directions. A realistic irradiation profile for the entire planned lifetime of the facility is used. The nuclear transmutation and decay of the produced radionuclides is calculated with the DeTra code which is a built-in tool for the MARS15 code. Radionuclide production by low-energy neutrons is calculated using the ENDF/B-VII evaluated nuclear data library. In order to estimate quality of this activation assessment, a comparison between calculated and measured activation of various foils in a similar radiation environment is presented.

Nuclear cargo detector

DOEpatents

Christo, Steven Basil

2006-12-19

Apparatus for the inspection of cargo containers for nuclear materials comprising one or more arrays of modules comprising grounded, closed conductive tubes filled with an ionizing gas mixture such as, but not limited to, Argon:CO.sub.2. A wire is suspended along each tube axis and electrically connected at both ends of the tube. A positive, dc high voltage is supplied to one end of the wire and an amplifier is attached to the other end through a capacitance to decouple the amplifier from the high voltage. X-rays, gamma rays or neutrons produced by nuclear material and passing through the tube ionize the gas. The electrons from the gas ionization process are accelerated toward the wire surface due to the wire's electrical potential. The acceleration of the electrons near the wire's surface is sufficient to ionize more gas and produce an amplification of electrons/ions that create a surge of current large enough to be detectable by the amplifier. Means are also provided for a warning device coupled to the amplifier.

HIGH TEMPERATURE SYSTEMS

DOEpatents

Thomson, G.P.; Blackman, M.

1961-07-25

BS>A device is descrined for producing nuclear fusion reactions by additional acceleration of a hydrogen isotope plasma formed and initially accelerated by a collapsing magnetic field. The plasma is enclosed in a toroidal cavity within a vessel composed of a plurality of insulated coaxial segments. The added acceleration is caused by providing progressing potentials to the insulated segments acting as electrodes by means of a segmented delay transmission line coupled to the electrode segments and excited by a two phase alternating current supply.

Activities report in nuclear physics and particle acceleration

NASA Astrophysics Data System (ADS)

Jansen, J. F. W.; Demeijer, R. J.

1984-04-01

Research on nuclear resonances; charge transfer; breakup of light and heavy ions; reaction mechanisms of heavy ion collisions; high-spin states; and fundamental symmetries in weak interactions are outlined. Group theoretical methods applied to supersymmetries; phenomenological description of rotation-vibration coupling; a microscopic theory of collective variables; the binding energy of hydrogen adsorbed on stepped platinium; and single electron capture are discussed. Isotopes for nuclear medicine, for off-line nuclear spectroscopy work, and for the study of hyperfine interactions were produced.

The development of enabling technologies for producing active interrogation beams.

PubMed

Kwan, Thomas J T; Morgado, Richard E; Wang, Tai-Sen F; Vodolaga, B; Terekhin, V; Onischenko, L M; Vorozhtsov, S B; Samsonov, E V; Vorozhtsov, A S; Alenitsky, Yu G; Perpelkin, E E; Glazov, A A; Novikov, D L; Parkhomchuk, V; Reva, V; Vostrikov, V; Mashinin, V A; Fedotov, S N; Minayev, S A

2010-10-01

A U.S./Russian collaboration of accelerator scientists was directed to the development of high averaged-current (∼1 mA) and high-quality (emittance ∼15 πmm mrad; energy spread ∼0.1%) 1.75 MeV proton beams to produce active interrogation beams that could be applied to counterterrorism. Several accelerator technologies were investigated. These included an electrostatic tandem accelerator of novel design, a compact cyclotron, and a storage ring with energy compensation and electron cooling. Production targets capable of withstanding the beam power levels were designed, fabricated, and tested. The cyclotron/storage-ring system was theoretically studied and computationally designed, and the electrostatic vacuum tandem accelerator at BINP was demonstrated for its potential in active interrogation of explosives and special nuclear materials.

Application of Advanced Nuclear Emulsion Technique to Fusion Neutron Diagnostics

NASA Astrophysics Data System (ADS)

Nakayama, Y.; Tomita, H.; Morishima, K.; Yamashita, F.; Hayashi, S.; Cheon, MunSeong; Isobe, M.; Ogawa, K.; Naka, T.; Nakano, T.; Nakamura, M.; Kawarabayashi, J.; Iguchi, T.; Ochiai, K.

In order to measure the 2.5 MeV neutrons produced by DD nuclear fusion reactions, we have developed a compact neutron detector based on nuclear emulsion. After optimization of development conditions, we evaluated the response of the detector to an accelerator-based DD neutron source. The absolute efficiency at an energy of 2.5 MeV was estimated to be (4.1±0.2)×10-6 tracks/neutron.

Activation Assessment of the Soil Around the ESS Accelerator Tunnel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rakhno, I. L.; Mokhov, N. V.; Tropin, I. S.

Activation of the soil surrounding the ESS accelerator tunnel calculated by the MARS15 code is presented. A detailed composition of the soil, that comprises about 30 different chemical elements, is considered. Spatial distributions of the produced activity are provided in both transverse and longitudinal direction. A realistic irradiation profile for the entire planned lifetime of the facility is used. The nuclear transmutation and decay of the produced radionuclides is calculated with the DeTra code which is a built-in tool for the MARS15 code. Radionuclide production by low-energy neutrons is calculated using the ENDF/B-VII evaluated nuclear data library. In order tomore » estimate quality of this activation assessment, a comparison between calculated and measured activation of various foils in a similar radiation environment is presented.« less

Fusion reactions initiated by laser-accelerated particle beams in a laser-produced plasma.

PubMed

Labaune, C; Baccou, C; Depierreux, S; Goyon, C; Loisel, G; Yahia, V; Rafelski, J

2013-01-01

The advent of high-intensity-pulsed laser technology enables the generation of extreme states of matter under conditions that are far from thermal equilibrium. This in turn could enable different approaches to generating energy from nuclear fusion. Relaxing the equilibrium requirement could widen the range of isotopes used in fusion fuels permitting cleaner and less hazardous reactions that do not produce high-energy neutrons. Here we propose and implement a means to drive fusion reactions between protons and boron-11 nuclei by colliding a laser-accelerated proton beam with a laser-generated boron plasma. We report proton-boron reaction rates that are orders of magnitude higher than those reported previously. Beyond fusion, our approach demonstrates a new means for exploring low-energy nuclear reactions such as those that occur in astrophysical plasmas and related environments.

First experimental results from 2 MeV proton tandem accelerator for neutron production.

PubMed

Kudryavtsev, A; Belchenko, Yu; Burdakov, A; Davydenko, V; Ivanov, A; Khilchenko, A; Konstantinov, S; Krivenko, A; Kuznetsov, A; Mekler, K; Sanin, A; Shirokov, V; Sorokin, I; Sulyaev, Yu; Tiunov, M

2008-02-01

A 2 MeV proton tandem accelerator with vacuum insulation was developed and first experiments are carried out in the Budker Institute of Nuclear Physics (Novosibirsk). The accelerator is designed for neutron production via reaction (7)Li(p,n)(7)Be for the boron neutron-capture therapy of the brain tumors, and for explosive detection based on 9.1724 MeV resonance gamma, which are produced via reaction (13)C(p,gamma)(14)N, absorption in nitrogen.

Accelerator Production of Isotopes for Medical Use

NASA Astrophysics Data System (ADS)

Lapi, Suzanne

2014-03-01

The increase in use of radioisotopes for medical imaging and therapy has led to the development of novel routes of isotope production. For example, the production and purification of longer-lived position emitting radiometals has been explored to allow for nuclear imaging agents based on peptides, antibodies and nanoparticles. These isotopes (64Cu, 89Zr, 86Y) are typically produced via irradiation of solid targets on smaller medical cyclotrons at dedicated facilities. Recently, isotope harvesting from heavy ion accelerator facilities has also been suggested. The Facility for Rare Isotope Beams (FRIB) will be a new national user facility for nuclear science to be completed in 2020. Radioisotopes could be produced by dedicated runs by primary users or may be collected synergistically from the water in cooling-loops for the primary beam dump that cycle the water at flow rates in excess of hundreds of gallons per minute. A liquid water target system for harvesting radioisotopes at the National Superconducting Cyclotron Laboratory (NSCL) was designed and constructed as the initial step in proof-of-principle experiments to harvest useful radioisotopes in this manner. This talk will provide an overview of isotope production using both dedicated machines and harvesting from larger accelerators typically used for nuclear physics. Funding from Department of Energy under DESC0007352 and DESC0006862.

Transmutation prospect of long-lived nuclear waste induced by high-charge electron beam from laser plasma accelerator

NASA Astrophysics Data System (ADS)

Wang, X. L.; Xu, Z. Y.; Luo, W.; Lu, H. Y.; Zhu, Z. C.; Yan, X. Q.

2017-09-01

Photo-transmutation of long-lived nuclear waste induced by a high-charge relativistic electron beam (e-beam) from a laser plasma accelerator is demonstrated. A collimated relativistic e-beam with a high charge of approximately 100 nC is produced from high-intensity laser interaction with near-critical-density (NCD) plasma. Such e-beam impinges on a high-Z convertor and then radiates energetic bremsstrahlung photons with flux approaching 1011 per laser shot. Taking a long-lived radionuclide 126Sn as an example, the resulting transmutation reaction yield is the order of 109 per laser shot, which is two orders of magnitude higher than obtained from previous studies. It is found that at lower densities, a tightly focused laser irradiating relatively longer NCD plasmas can effectively enhance the transmutation efficiency. Furthermore, the photo-transmutation is generalized by considering mixed-nuclide waste samples, which suggests that the laser-accelerated high-charge e-beam could be an efficient tool to transmute long-lived nuclear waste.

The production of radionuclides for nuclear medicine from a compact, low-energy accelerator system.

PubMed

Webster, William D; Parks, Geoffrey T; Titov, Dmitry; Beasley, Paul

2014-05-01

The field of nuclear medicine is reliant on radionuclides for medical imaging procedures and radioimmunotherapy (RIT). The recent shut-downs of key radionuclide producers have highlighted the fragility of the current radionuclide supply network, however. To ensure that nuclear medicine can continue to grow, adding new diagnostic and therapy options to healthcare, novel and reliable production methods are required. Siemens are developing a low-energy, high-current - up to 10 MeV and 1 mA respectively - accelerator. The capability of this low-cost, compact system for radionuclide production, for use in nuclear medicine procedures, has been considered. The production of three medically important radionuclides - (89)Zr, (64)Cu, and (103)Pd - has been considered, via the (89)Y(p,n), (64)Ni(p,n) and (103)Rh(p,n) reactions, respectively. Theoretical cross-sections were generated using TALYS and compared to experimental data available from EXFOR. Stopping power values generated by SRIM have been used, with the TALYS-generated excitation functions, to calculate potential yields and isotopic purity in different irradiation regimes. The TALYS excitation functions were found to have a good agreement with the experimental data available from the EXFOR database. It was found that both (89)Zr and (64)Cu could be produced with high isotopic purity (over 99%), with activity yields suitable for medical diagnostics and therapy, at a proton energy of 10MeV. At 10MeV, the irradiation of (103)Rh produced appreciable quantities of (102)Pd, reducing the isotopic purity. A reduction in beam energy to 9.5MeV increased the radioisotopic purity to 99% with only a small reduction in activity yield. This work demonstrates that the low-energy, compact accelerator system under development by Siemens would be capable of providing sufficient quantities of (89)Zr, (64)Cu, and (103)Pd for use in medical diagnostics and therapy. It is suggested that the system could be used to produce many other isotopes currently useful to nuclear medicine. Copyright © 2014 Elsevier Inc. All rights reserved.

Fissile interrogation using gamma rays from oxygen

DOEpatents

Smith, Donald; Micklich, Bradley J.; Fessler, Andreas

2004-04-20

The subject apparatus provides a means to identify the presence of fissionable material or other nuclear material contained within an item to be tested. The system employs a portable accelerator to accelerate and direct protons to a fluorine-compound target. The interaction of the protons with the fluorine-compound target produces gamma rays which are directed at the item to be tested. If the item to be tested contains either a fissionable material or other nuclear material the interaction of the gamma rays with the material contained within the test item with result in the production of neutrons. A system of neutron detectors is positioned to intercept any neutrons generated by the test item. The results from the neutron detectors are analyzed to determine the presence of a fissionable material or other nuclear material.

Solar gamma rays. [in solar flares

NASA Technical Reports Server (NTRS)

Ramaty, R.; Kozlovsky, B.; Lingenfelter, R. E.

1974-01-01

The theory of gamma ray production in solar flares is treated in detail. Both lines and continuum are produced. Results show that the strongest line predicted at 2.225 MeV with a width of less than 100 eV and detected at 2.24 + or - 2.02 MeV, is due to neutron capture by protons in the photosphere. Its intensity is dependent on the photospheric He-3 abundance. The neutrons are produced in nuclear reactions of flare accelerated particles which also produce positrons and prompt nuclear deexcitation lines. The strongest prompt lines are at 4.43 MeV from c-12 and at approximately 6.2 from 0-16 and N-15. The gamma ray continuum, produced by electron bremsstrahlung, allows the determination of the spectrum and number of accelerated electrons in the MeV region. From the comparison of the line and continuum intensities a proton-to-electron ratio of about 10 to 100 at the same energy for the 1972, August 4 flare. For the same flare the protons above 2.5 MeV which are responsible for the gamma ray emission produce a few percent of the heat generated by the electrons which make the hard X rays above 20 keV.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moon, Chang-Bum, E-mail: cbmoon@hoseo.edu

This paper outlines the new physics possibilities that fall within the field of nuclear structure and astrophysics based on experiments with radioactive ion beams at the future Rare Isotope Beams Accelerator facility in Korea. This ambitious multi-beam facility has both an Isotope Separation On Line (ISOL) and fragmentation capability to produce rare isotopes beams (RIBs) and will be capable of producing and accelerating beams of wide range mass of nuclides with energies of a few to hundreds MeV per nucleon. The large dynamic range of reaccelerated RIBs will allow the optimization in each nuclear reaction case with respect to crossmore » section and channel opening. The low energy RIBs around Coulomb barrier offer nuclear reactions such as elastic resonance scatterings, one or two particle transfers, Coulomb multiple-excitations, fusion-evaporations, and direct capture reactions for the study of the very neutron-rich and proton-rich nuclides. In contrast, the high energy RIBs produced by in-flight fragmentation with reaccelerated ions from the ISOL enable to explore the study of neutron drip lines in intermediate mass regions. The proposed studies aim at investigating the exotic nuclei near and beyond the nucleon drip lines, and to explore how nuclear many-body systems change in such extreme regions by addressing the following topics: the evolution of shell structure in areas of extreme proton to neutron imbalance; the study of the weak interaction in exotic decay schemes such as beta-delayed two-neutron or two-proton emission; the change of isospin symmetry in isobaric mirror nuclei at the drip lines; two protons or two neutrons radioactivity beyond the drip lines; the role of the continuum states including resonant states above the particle-decay threshold in exotic nuclei; and the effects of nuclear reaction rates triggered by the unbound proton-rich nuclei on nuclear astrophysical processes.« less

Production of 92Y via the 92Zr(n,p) reaction using the C(d,n) accelerator neutron source

NASA Astrophysics Data System (ADS)

Kin, Tadahiro; Sanzen, Yukimasa; Kamida, Masaki; Watanabe, Yukinobu; Itoh, Masatoshi

2017-09-01

We have proposed a new method of producing medical radioisotope 92Y as a candidate of alternatives of 111In bioscan prior to 90Y ibritumomab tiuxetan treatment. The 92Y isotope is produced via the 92Zr (n,p) reaction using accelerator neutrons generated by the interaction of deuteron beams with carbon. A feasibility experiment was performed at Cyclotron and Radioisotope Center, Tohoku University. A carbon thick target was irradiated by 20-MeV deuterons to produce accelerator neutrons. The thick target neutron yield (TTNY) was measured by using the multiple foils activation method. The foils were made of Al, Fe, Co, Ni, Zn, Zr, Nb, and Au. The production amount of 92Y and induced impurities were estimated by simulation with the measured TTNY and the JENDL-4.0 nuclear data.

Commercial Superconducting Electron Linac for Radioisotope Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grimm, Terry Lee; Boulware, Charles H.; Hollister, Jerry L.

2015-08-13

The majority of radioisotopes used in the United States today come from foreign suppliers or are generated parasitically in large government accelerators and nuclear reactors. Both of these restrictions limit the availability of radioisotopes and discourage the development and evaluation of new isotopes and for nuclear medicine, science, and industry. Numerous studies have been recommending development of dedicated accelerators for production of radioisotopes for over 20 years (Institute of Medicine, 1995; Reba, et al, 2000; National Research Council, 2007; NSAC 2009). The 2015 NSAC Long Range Plan for Isotopes again identified electron accelerators as an area for continued research andmore » development. Recommendation 1(c) from the 2015 NSAC Isotope report specifically identifies electron accelerators for continued funding for the purpose of producing medical and industrial radioisotopes. Recognizing the pressing need for new production methods of radioisotopes, the United States Congress passed the American Medical Isotope Production Act of 2012 to develop a domestic production of 99Mo and to eliminate the use of highly enriched uranium (HEU) in the production of 99Mo. One of the advantages of high power electron linear accelerators (linacs) is they can create both proton- and neutron-rich isotopes by generating high energy x-rays that knock out protons or neutrons from stable atoms or by fission of uranium. This allows for production of isotopes not possible in nuclear reactors. Recent advances in superconducting electron linacs have decreased the size and complexity of these systems such that they are economically competitive with nuclear reactors and large, high energy accelerators. Niowave, Inc. has been developing a radioisotope production facility based on a superconducting electron linac with liquid metal converters.« less

Nuclear reactions induced by high-energy alpha particles

NASA Technical Reports Server (NTRS)

Shen, B. S. P.

1974-01-01

Experimental and theoretical studies of nuclear reactions induced by high energy protons and heavier ions are included. Fundamental data needed in the shielding, dosimetry, and radiobiology of high energy particles produced by accelerators were generated, along with data on cosmic ray interaction with matter. The mechanism of high energy nucleon-nucleus reactions is also examined, especially for light target nuclei of mass number comparable to that of biological tissue.

Comparison of short-lived medical isotopes activation by laser thin target induced protons and conventional cyclotron proton beams

NASA Astrophysics Data System (ADS)

Murray, Joseph; Dudnikova, Galina; Liu, Tung-Chang; Papadopoulos, Dennis; Sagdeev, Roald; Su, J. J.; UMD MicroPET Team

2014-10-01

Production diagnostic or therapeutic nuclear medicines are either by nuclear reactors or by ion accelerators. In general, diagnostic nuclear radioisotopes have a very short half-life varying from tens of minutes for PET tracers and few hours for SPECT tracers. Thus supplies of PET and SPECT radiotracers are limited by regional production facilities. For example 18F-fluorodeoxyglucose (FDG) is the most desired tracer for positron emission tomography because its 110 minutes half-life is sufficient long for transport from production facilities to nearby users. From nuclear activation to completing image taking must be done within 4 hours. Decentralized production of diagnostic radioisotopes will be idea to make high specific activity radiotracers available to researches and clinicians. 11 C, 13 N, 15 O and 18 F can be produced in the energy range from 10-20 MeV by protons. Protons of energies up to tens of MeV generated by intense laser interacting with hydrogen containing targets have been demonstrated by many groups in the past decade. We use 2D PIC code for proton acceleration, Geant4 Monte Carlo code for nuclei activation to compare the yields and specific activities of short-lived isotopes produced by cyclotron proton beams and laser driven protons.

Recent Developments and Applications of Radiation/Detection Technology in Tsinghua University

NASA Astrophysics Data System (ADS)

Kang, Ke-Jun

2010-03-01

Nuclear technology applications have been very important research fields in Tsinghua University (THU) for more than 50 years. This paper describes two major directions and related projects running in THU concerning nuclear technology applications for radiation imaging and nuclear technology applications for astrophysics. Radiation imaging is a significant application of nuclear technology for all kinds of real world needs including security inspections, anti-smuggling operations, and medicine. The current improved imaging systems give much higher quality radiation images. THU has produced accelerating tubes for both industrial and medical accelerators with energy levels ranging from 2.5˜20Mev. Detectors have been produced for medical and industrial imaging as well as for high energy physics experiments such as the MRPC with fast time and position resolutions. DR and CT systems for radiation imaging systems have been continuously improved with new system designs and improved algorithms for image reconstruction and processing. Two important new key initiatives are the dual-energy radiography and dual-energy CT systems. Dual-energy CT imaging improves material discrimination by providing both the electron density and the atomic number distribution of scanned objects. Finally, this paper also introduces recent developments related to the hard X-ray modulation telescope (HXMT) provided by THU.

Rare Isotopes in Cosmic Explosions and Accelerators on Earth

ScienceCinema

Schatz, Hendrick

2017-12-28

Rare isotopes are nature’s stepping stones to produce the heavy elements, and they are produced in large quantities in stellar explosions. Despite their fleeting existence, they shape the composition of the universe and the observable features of stellar explosions. The challenge for nuclear science is to produce and study the very same rare isotopes so as to understand the origin of the elements and a range of astronomical observations. I will review the progress that has been made to date in astronomy and nuclear physics, and the prospects of finally addressing many of the outstanding issues with the future Facility for Rare Isotope Beams (FRIB), which DOE will build at Michigan State University.

ILU industrial electron accelerators for medical-product sterilization and food treatment

NASA Astrophysics Data System (ADS)

Bezuglov, V. V.; Bryazgin, A. A.; Vlasov, A. Yu.; Voronin, L. A.; Panfilov, A. D.; Radchenko, V. M.; Tkachenko, V. O.; Shtarklev, E. A.

2016-12-01

Pulse linear electron accelerators of the ILU type have been developed and produced by the Institute of Nuclear Physics, Siberian Branch, Russian Academy of Sciences, for more than 30 years. Their distinctive features are simplicity of design, convenience in operation, and reliability during long work under conditions of industrial production. ILU accelerators have a range of energy of 0.7-10 MeV at a power of accelerated beam of up to 100 kW and they are optimally suitable for use as universal sterilizing complexes. The scientific novelty of these accelerators consists of their capability to work both in the electron-treatment mode of production and in the bremsstrahlung generation mode, which has high penetrating power.

EVIDENCE FOR ENHANCED {sup 3}HE IN FLARE-ACCELERATED PARTICLES BASED ON NEW CALCULATIONS OF THE GAMMA-RAY LINE SPECTRUM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murphy, R. J.; Kozlovsky, B.; Share, G. H., E-mail: murphy@ssd5.nrl.navy.mil, E-mail: benz@wise.tau.ac.il, E-mail: share@astro.umd.edu

2016-12-20

The {sup 3}He abundance in impulsive solar energetic particle (SEP) events is enhanced up to several orders of magnitude compared to its photospheric value of [{sup 3}He]/[{sup 4}He] = 1–3 × 10{sup −4}. Interplanetary magnetic field and timing observations suggest that these events are related to solar flares. Observations of {sup 3}He in flare-accelerated ions would clarify the relationship between these two phenomena. Energetic {sup 3}He interactions in the solar atmosphere produce gamma-ray nuclear-deexcitation lines, both lines that are also produced by protons and α particles and lines that are essentially unique to {sup 3}He. Gamma-ray spectroscopy can, therefore, reveal enhanced levelsmore » of accelerated {sup 3}He. In this paper, we identify all significant deexcitation lines produced by {sup 3}He interactions in the solar atmosphere. We evaluate their production cross sections and incorporate them into our nuclear deexcitation-line code. We find that enhanced {sup 3}He can affect the entire gamma-ray spectrum. We identify gamma-ray line features for which the yield ratios depend dramatically on the {sup 3}He abundance. We determine the accelerated {sup 3}He/ α ratio by comparing these ratios with flux ratios measured previously from the gamma-ray spectrum obtained by summing the 19 strongest flares observed with the Solar Maximum Mission Gamma-Ray Spectrometer. All six flux ratios investigated show enhanced {sup 3}He, confirming earlier suggestions. The {sup 3}He/ α weighted mean of these new measurements ranges from 0.05 to 0.3 (depending on the assumed accelerated α /proton ratio) and has a <1 × 10{sup −3} probability of being consistent with the photospheric value. With the improved code, we can now exploit the full potential of gamma-ray spectroscopy to establish the relationship between flare-accelerated ions and {sup 3}He-rich SEPs.« less

Method and apparatus for generating low energy nuclear particles

DOEpatents

Powell, J.R.; Reich, M.; Ludewig, H.; Todosow, M.

1999-02-09

A particle accelerator generates an input particle beam having an initial energy level above a threshold for generating secondary nuclear particles. A thin target is rotated in the path of the input beam for undergoing nuclear reactions to generate the secondary particles and correspondingly decrease energy of the input beam to about the threshold. The target produces low energy secondary particles and is effectively cooled by radiation and conduction. A neutron scatterer and a neutron filter are also used for preferentially degrading the secondary particles into a lower energy range if desired. 18 figs.

First neutron generation in the BINP accelerator based neutron source.

PubMed

Bayanov, B; Burdakov, A; Chudaev, V; Ivanov, A; Konstantinov, S; Kuznetsov, A; Makarov, A; Malyshkin, G; Mekler, K; Sorokin, I; Sulyaev, Yu; Taskaev, S

2009-07-01

Pilot innovative facility for neutron capture therapy was built at Budker Institute of Nuclear Physics, Novosibirsk. This facility is based on a compact vacuum insulation tandem accelerator designed to produce proton current up to 10 mA. Epithermal neutrons are proposed to be generated by 1.915 MeV protons bombarding a lithium target using (7)Li(p,n)(7)Be threshold reaction. The results of the first experiments on neutron generation are reported and discussed.

Accelerator-driven Transmutation of Waste

NASA Astrophysics Data System (ADS)

Venneri, Francesco

1998-04-01

Nuclear waste from commercial power plants contains large quantities of plutonium, other fissionable actinides, and long-lived fission products that are potential proliferation concerns and create challenges for the long-term storage. Different strategies for dealing with nuclear waste are being followed by various countries because of their geologic situations and their views on nuclear energy, reprocessing and non-proliferation. The current United States policy is to store unprocessed spent reactor fuel in a geologic repository. Other countries are opting for treatment of nuclear waste, including partial utilization of the fissile material contained in the spent fuel, prior to geologic storage. Long-term uncertainties are hampering the acceptability and eventual licensing of a geologic repository for nuclear spent fuel in the US, and driving up its cost. The greatest concerns are with the potential for radiation release and exposure from the spent fuel for tens of thousands of years and the possible diversion and use of the actinides contained in the waste for weapons construction. Taking advantage of the recent breakthroughs in accelerator technology and of the natural flexibility of subcritical systems, the Accelerator-driven Transmutation of Waste (ATW) concept offers the United States and other countries the possibility to greatly reduce plutonium, higher actinides and environmentally hazardous fission products from the waste stream destined for permanent storage. ATW does not eliminate the need for, but instead enhances the viability of permanent waste repositories. Far from being limited to waste destruction, the ATW concept also brings to the table new technologies that could be relevant for next-generation power producing reactors. In the ATW concept, spent fuel would be shipped to the ATW site where the plutonium, transuranics and selected long-lived fission products would be destroyed by fission or transmutation in their first and only pass through the facility, using an accelerator-driven subcritical burner cooled by liquid lead/bismuth and limited pyrochemical treatment of the spent fuel and residual waste. This approach contrasts with the present-day practices of aqueous reprocessing (Europe and Japan), in which high purity plutonium is produced and used in the fabrication of fresh mixed oxide fuel (MOX) that is shipped off-site for use in light water reactors.

Temporal narrowing of neutrons produced by high-intensity short-pulse lasers

DOE PAGES

Higginson, D. P.; Vassura, L.; Gugiu, M. M.; ...

2015-07-28

The production of neutron beams having short temporal duration is studied using ultraintense laser pulses. Laser-accelerated protons are spectrally filtered using a laser-triggered microlens to produce a short duration neutron pulse via nuclear reactions induced in a converter material (LiF). This produces a ~3 ns duration neutron pulse with 10 4 n/MeV/sr/shot at 0.56 m from the laser-irradiated proton source. The large spatial separation between the neutron production and the proton source allows for shielding from the copious and undesirable radiation resulting from the laser-plasma interaction. Finally, this neutron pulse compares favorably to the duration of conventional accelerator sources andmore » should scale up with, present and future, higher energy laser facilities to produce brighter and shorter neutron beams for ultrafast probing of dense materials.« less

10 CFR 35.10 - Implementation.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Implementation. 35.10 Section 35.10 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL General Information § 35.10 Implementation. (a) A Government agency or a Federally recognized Indian Tribe that possesses and uses accelerator-produced...

A strong-focusing 800 MeV cyclotron for high-current applications

NASA Astrophysics Data System (ADS)

Pogue, N.; Assadi, S.; Badgley, K.; Comeaux, J.; Kellams, J.; McInturff, A.; McIntyre, P.; Sattarov, A.

2013-04-01

A superconducting strong-focusing cyclotron (SFC) is being developed for high-current applications. It incorporates four innovations. Superconducting quarter-wave cavities are used to provide >20 MV/turn acceleration. The orbit separation is thereby opened so that bunch-bunch interactions between successive orbits are eliminated. Quadrapole focusing channels are incorporated within the sectors so that alternating-gradient strong-focusing transport is maintained throughout. Dipole windings on the inner and outer orbits provide enhanced control for injection and extraction of bunches. Finally each sector magnet is configured as a flux-coupled stack of independent apertures, so that any desired number of independent cyclotrons can be integrated within a common footprint. Preliminary simulations indicate that each SFC should be capable of accelerating 10 mA CW to 800 MeV with very low loss and >50% energy efficiency. A primary motivation for SFC is as a proton driver for accelerator-driven subcritical fission in a molten salt core. The cores are fueled solely with the transuranics from spent nuclear fuel from a conventional nuclear power plant. The beams from one SFC stack would destroy all of the transuranics and long-lived fission products that are produced by a GWe reactor [1]. This capability offers the opportunity to close the nuclear fuel cycle and provide a path to green nuclear energy.

Nuclear Physics with 10 PW laser beams at Extreme Light Infrastructure - Nuclear Physics (ELI-NP)

NASA Astrophysics Data System (ADS)

Zamfir, N. V.

2014-05-01

The field of the uncharted territory of high-intensity laser interaction with matter is confronted with new exotic phenomena and, consequently, opens new research perspectives. The intense laser beams interacting with a gas or solid target generate beams of electrons, protons and ions. These beams can induce nuclear reactions. Electrons also generate ions high-energy photons via bremsstrahlung processes which can also induce nuclear reactions. In this context a new research domain began to form in the last decade or so, namely nuclear physics with high power lasers. The observation of high brilliance proton beams of tens of MeV energy from solid targets has stimulated an intense research activity. The laser-driven particle beams have to compete with conventional nuclear accelerator-generated beams. The ultimate goal is aiming at applications of the laser produced beams in research, technology and medicine. The mechanism responsible for ion acceleration are currently subject of intensive research in many laboratories in the world. The existing results, experimental and theoretical, and their perspectives are reviewed in this article in the context of IZEST and the scientific program of ELI-NP.

A review of carbide fuel corrosion for nuclear thermal propulsion applications

NASA Astrophysics Data System (ADS)

Pelaccio, Dennis G.; El-Genk, Mohamed S.; Butt, Darryl P.

1993-10-01

At the operation conditions of interest in nuclear thermal propulsion reactors, carbide materials have been known to exhibit a number of life limiting phenomena. These include the formation of liquid, loss by vaporization, creep and corresponding gas flow restrictions, and local corrosion and fuel structure degradation due to excessive mechanical and/or thermal loading. In addition, the radiation environment in the reactor core can produce a substantial change in its local physical properties, which can produce high thermal stresses and corresponding stress fractures (cracking). Time-temperature history and cyclic operation of the nuclear reactor can also accelerate some of these processes. The University of New Mexico's Institute for Space Nuclear Power Studies, under NASA sponsorship has recently initiated a study to model the complicated hydrogen corrosion process. In support of this effort, an extensive review of the open literature was performed, and a technical expert workshop was conducted. This paper summarizes the results of this review.

A Review of Carbide Fuel Corrosion for Nuclear Thermal Propulsion Applications

NASA Astrophysics Data System (ADS)

Pelaccio, Dennis G.; El-Genk, Mohamed S.; Butt, Darryl P.

1994-07-01

At the operation conditions of interest in nuclear thermal propulsion reactors, carbide materials have been known to exhibit a number of life limiting phenomena. These include the formation of liquid, loss by vaporization, creep and corresponding gas flow restrictions, and local corrosion and fuel structure degradation due to excessive mechanical and/or thermal loading. In addition, the radiation environment in the reactor core can produce a substantial change in its local physical properties, which can produce high thermal stresses and corresponding stress fractures (cracking). Time-temperature history and cyclic operation of the nuclear reactor can also accelerate some of these processes. The University of New Mexico's Institute for Space Nuclear Power Studies, under NASA sponsorship has recently initiated a study to model the complicated hydrogen corrosion process. In support of this effort, an extensive review of the open literature was performed, and a technical expert workshop was conducted. This paper summarizes the results of this review.

Fission-Produced 99Mo Without a Nuclear Reactor.

PubMed

Youker, Amanda J; Chemerisov, Sergey D; Tkac, Peter; Kalensky, Michael; Heltemes, Thad A; Rotsch, David A; Vandegrift, George F; Krebs, John F; Makarashvili, Vakho; Stepinski, Dominique C

2017-03-01

99 Mo, the parent of the widely used medical isotope 99m Tc, is currently produced by irradiation of enriched uranium in nuclear reactors. The supply of this isotope is encumbered by the aging of these reactors and concerns about international transportation and nuclear proliferation. Methods: We report results for the production of 99 Mo from the accelerator-driven subcritical fission of an aqueous solution containing low enriched uranium. The predominately fast neutrons generated by impinging high-energy electrons onto a tantalum convertor are moderated to thermal energies to increase fission processes. The separation, recovery, and purification of 99 Mo were demonstrated using a recycled uranyl sulfate solution. Conclusion: The 99 Mo yield and purity were found to be unaffected by reuse of the previously irradiated and processed uranyl sulfate solution. Results from a 51.8-GBq 99 Mo production run are presented. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

"DIANA" - A New, Deep-Underground Accelerator Facility for Astrophysics Experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leitner, M.; Leitner, D.; Lemut, A.

2009-05-28

The DIANA project (Dakota Ion Accelerators for Nuclear Astrophysics) is a collaboration between the University of Notre Dame, University of North Carolina, Western Michigan University, and Lawrence Berkeley National Laboratory to build a nuclear astrophysics accelerator facility 1.4 km below ground. DIANA is part of the US proposal DUSEL (Deep Underground Science and Engineering Laboratory) to establish a cross-disciplinary underground laboratory in the former gold mine of Homestake in South Dakota, USA. DIANA would consist of two high-current accelerators, a 30 to 400 kV variable, high-voltage platform, and a second, dynamitron accelerator with a voltage range of 350 kV tomore » 3 MV. As a unique feature, both accelerators are planned to be equipped with either high-current microwave ion sources or multi-charged ECR ion sources producing ions from protons to oxygen. Electrostatic quadrupole transport elements will be incorporated in the dynamitron high voltage column. Compared to current astrophysics facilities, DIANA could increase the available beam densities on target by magnitudes: up to 100 mA on the low energy accelerator and several mA on the high energy accelerator. An integral part of the DIANA project is the development of a high-density super-sonic gas-jet target which can handle these anticipated beam powers. The paper will explain the main components of the DIANA accelerators and their beam transport lines and will discuss related technical challenges.« less

Prediction of ground motion and dynamic stress change in Baekdusan (Changbaishan) volcano caused by a North Korean nuclear explosion.

PubMed

Hong, Tae-Kyung; Choi, Eunseo; Park, Seongjun; Shin, Jin Soo

2016-02-17

Strong ground motions induce large dynamic stress changes that may disturb the magma chamber of a volcano, thus accelerating the volcanic activity. An underground nuclear explosion test near an active volcano constitutes a direct treat to the volcano. This study examined the dynamic stress changes of the magma chamber of Baekdusan (Changbaishan) that can be induced by hypothetical North Korean nuclear explosions. Seismic waveforms for hypothetical underground nuclear explosions at North Korean test site were calculated by using an empirical Green's function approach based on a source-spectral model of a nuclear explosion; such a technique is efficient for regions containing poorly constrained velocity structures. The peak ground motions around the volcano were estimated from empirical strong-motion attenuation curves. A hypothetical M7.0 North Korean underground nuclear explosion may produce peak ground accelerations of 0.1684 m/s(2) in the horizontal direction and 0.0917 m/s(2) in the vertical direction around the volcano, inducing peak dynamic stress change of 67 kPa on the volcano surface and ~120 kPa in the spherical magma chamber. North Korean underground nuclear explosions with magnitudes of 5.0-7.6 may induce overpressure in the magma chamber of several tens to hundreds of kilopascals.

A MiniBooNE Accelerator-Produced (sub)-GeV Dark Matter Search

NASA Astrophysics Data System (ADS)

Thornton, Remington; MiniBooNE-DM Collaboration

2016-09-01

Cosmological observations indicate that our universe contains dark matter (DM), yet we have no measurements of its microscopic properties. Whereas the gravitational interaction of DM is well understood, its interaction with the Standard Model is not. Direct detection experiments search for a nuclear recoil interaction produced by a DM relic particle and have a low-mass sensitivity edge of order 1 GeV. To detect DM with mass below 1 GeV, either the sensitivity of the experiments needs to be improved or use of accelerators producing boosted low-mass DM are needed. Using neutrino detectors to search for low-mass DM is logical due to the similarity of the DM and ν signatures in the detector. The MiniBooNE experiment, located at Fermilab on the Booster Neutrino Beamline, ran for 10 years in ν and ν modes and is already well understood, making it desirable to search for accelerator-produced boosted low-mass DM. A search for DM produced by 8 GeV protons hitting a steel beam-dump has finished, collecting 1 . 86 ×1020 POT . Final analysis containing 90% confidence limits and a model independent fit will be presented.

Method and apparatus for generating low energy nuclear particles

DOEpatents

Powell, James R.; Reich, Morris; Ludewig, Hans; Todosow, Michael

1999-02-09

A particle accelerator (12) generates an input particle beam having an initial energy level above a threshold for generating secondary nuclear particles. A thin target (14) is rotated in the path of the input beam for undergoing nuclear reactions to generate the secondary particles and correspondingly decrease energy of the input beam to about the threshold. The target (14) produces low energy secondary particles and is effectively cooled by radiation and conduction. A neutron scatterer (44) and a neutron filter (42) are also used for preferentially degrading the secondary particles into a lower energy range if desired.

Introduction to spallation physics and spallation-target design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russell, G.J.; Pitcher, E.J.; Daemen, L.L.

1995-10-01

When coupled with the spallation process in appropriate target materials, high-power accelerators can be used to produce large numbers of neutrons, thus providing an alternate method to the use of nuclear reactors for this purpose. Spallation offers exciting new possibilities for generating intense neutron fluxes for a variety of applications, including: (a) spallation-neutron sources for materials science research; (b) accelerator-based production of tritium; (c) accelerator-based transmutation of waste; (d) accelerator-based destruction of plutonium; and (e) radioisotope production for medical and energy applications. Target design plays a key role in these applications, with neutron production/leakage being strongly dependent on the incidentmore » particle type and energy, and target material and geometry.« less

Perspectives of boron-neutron capture therapy of malignant brain tumors

NASA Astrophysics Data System (ADS)

Kanygin, V. V.; Kichigin, A. I.; Krivoshapkin, A. L.; Taskaev, S. Yu.

2017-09-01

Boron neutron capture therapy (BNCT) is characterized by a selective effect directly on the cells of malignant tumors. The carried out research showed the perspective of the given kind of therapy concerning malignant tumors of the brain. However, the introduction of BNCT into clinical practice is hampered by the lack of a single protocol for the treatment of patients and the difficulty in using nuclear reactors to produce a neutron beam. This problem can be solved by using a compact accelerator as a source of neutrons, with the possibility of installation in a medical institution. Such a neutron accelerator for BNCT was developed at Budker Institute of Nuclear Physics, Novosibirsk. A neutron beam was obtained on this accelerator, which fully complies with the requirements of BNCT, as confirmed by studies on cell cultures and experiments with laboratory animals. The conducted experiments showed the relative safety of the method with the absence of negative effects on cell cultures and living organisms, and also confirmed the effectiveness of BNCT for malignant brain tumors.

Applications in Nuclear Energy Security

NASA Astrophysics Data System (ADS)

Sheffield, Richard

2009-05-01

A key roadblock to development of additional nuclear power capacity is a concern over management of nuclear waste. Nuclear waste is predominantly comprised of used fuel discharged from operating nuclear reactors. The roughly 100 operating US reactors currently produce about 20% of the US electricity and will create about 87,000 tons of such discharged or ``spent'' fuel over the course of their lifetimes. The long-term radioactivity of the spent fuel drives the need for deep geologic storage that remains stable for millions of years. Nearly all issues related to risks to future generations arising from long-term disposal of such spent nuclear fuel is attributable to approximately the 1% made up primarily of minor actinides. If we can reduce or eliminate this 1% of the spent fuel, then within a few hundred years the toxic nature of the spent fuel drops below that of the natural uranium ore that was originally mined for nuclear fuel. The minor actinides can be efficiently eliminated through nuclear transmutation using as a driver fast-neutrons produced by a spallation process initiated with a high-energy proton beam. This presentation will cover the system design considerations and issues of an accelerator driven transmutation system.

Construction of a 1 MeV Electron Accelerator for High Precision Beta Decay Studies

NASA Astrophysics Data System (ADS)

Longfellow, Brenden

2014-09-01

Beta decay energy calibration for detectors is typically established using conversion sources. However, the calibration points from conversion sources are not evenly distributed over the beta energy spectrum and the foil backing of the conversion sources produces perturbations in the calibration spectrum. To improve this, an external, tunable electron beam coupled by a magnetic field can be used to calibrate the detector. The 1 MeV electron accelerator in development at Triangle Universities Nuclear Laboratory (TUNL) utilizes a pelletron charging system. The electron gun shoots 104 electrons per second with an energy range of 50 keV to 1 MeV and is pulsed at a 10 kHz rate with a few ns width. The magnetic field in the spectrometer is 1 T and guiding fields of 0.01 to 0.05 T for the electron gun are used to produce a range of pitch angles. This accelerator can be used to calibrate detectors evenly over its energy range and determine the detector response over a range of pitch angles. Beta decay energy calibration for detectors is typically established using conversion sources. However, the calibration points from conversion sources are not evenly distributed over the beta energy spectrum and the foil backing of the conversion sources produces perturbations in the calibration spectrum. To improve this, an external, tunable electron beam coupled by a magnetic field can be used to calibrate the detector. The 1 MeV electron accelerator in development at Triangle Universities Nuclear Laboratory (TUNL) utilizes a pelletron charging system. The electron gun shoots 104 electrons per second with an energy range of 50 keV to 1 MeV and is pulsed at a 10 kHz rate with a few ns width. The magnetic field in the spectrometer is 1 T and guiding fields of 0.01 to 0.05 T for the electron gun are used to produce a range of pitch angles. This accelerator can be used to calibrate detectors evenly over its energy range and determine the detector response over a range of pitch angles. TUNL REU Program.

Proposed BISOL Facility - a Conceptual Design

NASA Astrophysics Data System (ADS)

Ye, Yanlin

2018-05-01

In China, a new large-scale nuclear-science research facility, namely the "Beijing Isotope-Separation-On-Line neutron-rich beam facility (BISOL)", has been proposed and reviewed by the governmental committees. This facility aims at both basic science and application goals, and is based on a double-driver concept. On the basic science side, the radioactive ion beams produced from the ISOL device, driven by a research reactor or by an intense deuteron-beam ac- celerator, will be used to study the new physics and technologies at the limit of the nuclear stability in the medium mass region. On the other side regarding to the applications, the facility will be devoted to the material research asso- ciated with the nuclear energy system, by using typically the intense neutron beams produced from the deuteron-accelerator driver. The initial design will be outlined in this report.

The Neutrons for Science Facility at SPIRAL-2.

PubMed

Ledoux, X; Aïche, M; Avrigeanu, M; Avrigeanu, V; Balanzat, E; Ban-d'Etat, B; Ban, G; Bauge, E; Bélier, G; Bém, P; Borcea, C; Caillaud, T; Chatillon, A; Czajkowski, S; Dessagne, P; Doré, D; Fischer, U; Frégeau, M O; Grinyer, J; Guillous, S; Gunsing, F; Gustavsson, C; Henning, G; Jacquot, B; Jansson, K; Jurado, B; Kerveno, M; Klix, A; Landoas, O; Lecolley, F R; Lecouey, J L; Majerle, M; Marie, N; Materna, T; Mrázek, J; Novák, J; Oberstedt, S; Oberstedt, A; Panebianco, S; Perrot, L; Plompen, A J M; Pomp, S; Prokofiev, A V; Ramillon, J M; Farget, F; Ridikas, D; Rossé, B; Serot, O; Simakov, S P; Šimecková, E; Stanoiu, M; Štefánik, M; Sublet, J C; Taïeb, J; Tarrío, D; Tassan-Got, L; Thfoin, I; Varignon, C

2017-11-21

The neutrons for science (NFS) facility is a component of SPIRAL-2, the new superconducting linear accelerator built at GANIL in Caen (France). The proton and deuteron beams delivered by the accelerator will allow producing intense neutron fields in the 100 keV-40 MeV energy range. Continuous and quasi-mono-kinetic energy spectra, respectively, will be available at NFS, produced by the interaction of a deuteron beam on a thick Be converter and by the 7Li(p,n) reaction on thin converter. The pulsed neutron beam, with a flux up to two orders of magnitude higher than those of other existing time-of-flight facilities, will open new opportunities of experiments in fundamental research as well as in nuclear data measurements. In addition to the neutron beam, irradiation stations for neutron-, proton- and deuteron-induced reactions will be available for cross-sections measurements and for the irradiation of electronic devices or biological cells. NFS, whose first experiment is foreseen in 2018, will be a very powerful tool for physics, fundamental research as well as applications like the transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

On the Applications of IBA Techniques to Biological Samples Analysis: PIXE and RBS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Falcon-Gonzalez, J. M.; Bernal-Alvarado, J.; Sosa, M.

2008-08-11

The analytical techniques based on ion beams or IBA techniques give quantitative information on elemental concentration in samples of a wide variety of nature. In this work, we focus on PIXE technique, analyzing thick target biological specimens (TTPIXE), using 3 MeV protons produced by an electrostatic accelerator. A nuclear microprobe was used performing PIXE and RBS simultaneously, in order to solve the uncertainties produced in the absolute PIXE quantifying. The advantages of using both techniques and a nuclear microprobe are discussed. Quantitative results are shown to illustrate the multielemental resolution of the PIXE technique; for this, a blood standard wasmore » used.« less

Targets used in the production of radioactive ion beams at the HRIBF

NASA Astrophysics Data System (ADS)

Stracener, D. W.; Alton, G. D.; Auble, R. L.; Beene, J. R.; Mueller, P. E.; Bilheux, J. C.

2004-03-01

Radioactive ion beams are produced at the Holifield Radioactive Ion Beam Facility using the Isotope Separation On-Line (ISOL) technique where the atoms are produced in a thick target, transported to an ion source, ionized, and extracted from the ion source to form an ion beam. These radioactive ion beams are then accelerated to energies of a few MeV per nucleon and delivered to experimental stations for use in nuclear physics and nuclear astrophysics experiments. At the heart of this facility is the RIB production target, where the radioactive nuclei are produced using beams of light ions (p, d, 3He, α) to induce nuclear reactions in the target nuclei. Several target materials have been developed and used successfully, including Al 2O 3, HfO 2, SiC, CeS, liquid Ge, liquid Ni, and a low-density matrix of uranium carbide. The details of these targets and some of the target developments that led to the delivery of high-quality radioactive ion beams are discussed in this paper.

Solar Gamma Rays Above 8 MeV

NASA Technical Reports Server (NTRS)

Crannell, C. J.; Crannell, H.; Ramaty, R.

1978-01-01

Processes which lead to the production of gamma rays with energy greater than 8 MeV in solar flares are reviewed and evaluated. Excited states produced by inelastic scattering, charge exchange, and spallation reactions in the abundant nuclear species are considered in order to identify nuclear lines which may contribute to the Gamma ray spectrum of solar flares. The flux of 15.11 MeV Gamma rays relative to the flux of 4.44 MeV Gamma rays from the de-excitation of the corresponding states in C12 is calculated for a number of assumed distributions of exciting particles. This flux ratio is a sensitive diagnostic of accelerated particle spectra. Other high energy nuclear levels are not so isolated as the 15.11 MeV state and are not expected to be so strong. The spectrum of Gamma rays from the decay of Pi dey is sensitive to the energy distribution of particles accelerated to energies greater than 100 MeV.

Use of the CEBAF Accelerator for IR and UV Free Electron Lasers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yunn, Byung; Sinclair, Charles; Leemann, Christoph

1992-08-01

The CEBAF superconducting linac is capable of accelerating electron beams suitable for driving high-power free-electron lasers. The 45 MeV injector linac with a 6 cm period wiggler can produce kilowatt output powers of infrared light (3.6-17 micrometer), while the 400 MeV north linac can produce ultraviolet light (~200 nm) at similar powers. The FELs require the addition of a high-peak intensity electron source (~ 60 A peak current) and extraction beam lines to wigglers with appropriate electron and photon optics. FEL operation is compatible with simultaneous baseline CEBAF nuclear physics operation. A design for a CEBAF-based FEL facility has beenmore » developed. The current status of the FEL project is reported.« less

Prediction of ground motion and dynamic stress change in Baekdusan (Changbaishan) volcano caused by a North Korean nuclear explosion

PubMed Central

Hong, Tae-Kyung; Choi, Eunseo; Park, Seongjun; Shin, Jin Soo

2016-01-01

Strong ground motions induce large dynamic stress changes that may disturb the magma chamber of a volcano, thus accelerating the volcanic activity. An underground nuclear explosion test near an active volcano constitutes a direct treat to the volcano. This study examined the dynamic stress changes of the magma chamber of Baekdusan (Changbaishan) that can be induced by hypothetical North Korean nuclear explosions. Seismic waveforms for hypothetical underground nuclear explosions at North Korean test site were calculated by using an empirical Green’s function approach based on a source-spectral model of a nuclear explosion; such a technique is efficient for regions containing poorly constrained velocity structures. The peak ground motions around the volcano were estimated from empirical strong-motion attenuation curves. A hypothetical M7.0 North Korean underground nuclear explosion may produce peak ground accelerations of 0.1684 m/s2 in the horizontal direction and 0.0917 m/s2 in the vertical direction around the volcano, inducing peak dynamic stress change of 67 kPa on the volcano surface and ~120 kPa in the spherical magma chamber. North Korean underground nuclear explosions with magnitudes of 5.0–7.6 may induce overpressure in the magma chamber of several tens to hundreds of kilopascals. PMID:26884136

Cross Section Measurements Using the Zero Degree Detector

NASA Technical Reports Server (NTRS)

Christl, M. J.; Adams, J. H., Jr.; Heilbronn, L.; Kuznetsov, E. N.; Miller, J.; Zeitlin, C.

2007-01-01

The Zero Degree Detector (ZDD) is an instrument that has been used in accelerator exposures to measure the angular dependence of particles produced in heavy ion fragmentation experiments. The ZDD uses two identical layers of pixelated silicon detectors that make coincident measurements over the active area of the instrument. The angular distribution of secondary particle produced in nuclear interactions for several heavy ions: and target materials will be presented along with performance characteristic of the instrument.

The RaDIATE High-Energy Proton Materials Irradiation Experiment at the Brookhaven Linac Isotope Producer Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ammigan, Kavin; et al.

The RaDIATE collaboration (Radiation Damage In Accelerator Target Environments) was founded in 2012 to bring together the high-energy accelerator target and nuclear materials communities to address the challenging issue of radiation damage effects in beam-intercepting materials. Success of current and future high intensity accelerator target facilities requires a fundamental understanding of these effects including measurement of materials property data. Toward this goal, the RaDIATE collaboration organized and carried out a materials irradiation run at the Brookhaven Linac Isotope Producer facility (BLIP). The experiment utilized a 181 MeV proton beam to irradiate several capsules, each containing many candidate material samples formore » various accelerator components. Materials included various grades/alloys of beryllium, graphite, silicon, iridium, titanium, TZM, CuCrZr, and aluminum. Attainable peak damage from an 8-week irradiation run ranges from 0.03 DPA (Be) to 7 DPA (Ir). Helium production is expected to range from 5 appm/DPA (Ir) to 3,000 appm/DPA (Be). The motivation, experimental parameters, as well as the post-irradiation examination plans of this experiment are described.« less

Active interrogation using low-energy nuclear reactions

NASA Astrophysics Data System (ADS)

Antolak, Arlyn; Doyle, Barney; Leung, Ka-Ngo; Morse, Daniel; Provencio, Paula

2005-09-01

High-energy photons and neutrons can be used to interrogate for heavily shielded fissile materials inside sealed cargo containers by detecting their prompt and/or delayed fission signatures. The FIND (Fissmat Inspection for Nuclear Detection) active interrogation system is based on a dual neutron+gamma source that uses low-energy (< 500 keV) proton- or deuteron-induced nuclear reactions to produce high intensities of mono-energetic gamma rays and/or neutrons. The source can be operated in either pulsed (e.g., to detect delayed photofission neutrons and gammas) or continuous (e.g., detecting prompt fission signatures) modes. For the gamma-rays, the source target can be segmented to incorporate different (p,γ) isotopes for producing gamma-rays at selective energies, thereby improving the probability of detection. The design parameters for the FIND system are discussed and preliminary accelerator-based measurements of gamma and neutron yields, background levels, and fission signals for several target materials under consideration are presented.

The Neutrons for Science Facility at SPIRAL-2

NASA Astrophysics Data System (ADS)

Ledoux, X.; Aïche, M.; Avrigeanu, M.; Avrigeanu, V.; Audouin, L.; Balanzat, E.; Ban-détat, B.; Ban, G.; Barreau, G.; Bauge, E.; Bélier, G.; Bem, P.; Blideanu, V.; Borcea, C.; Bouffard, S.; Caillaud, T.; Chatillon, A.; Czajkowski, S.; Dessagne, P.; Doré, D.; Fallot, M.; Farget, F.; Fischer, U.; Giot, L.; Granier, T.; Guillous, S.; Gunsing, F.; Gustavsson, C.; Jacquot, B.; Jansson, K.; Jurado, B.; Kerveno, M.; Klix, A.; Landoas, O.; Lecolley, F. R.; Lecouey, J. L.; Majerle, M.; Marie, N.; Materna, T.; Mrazek, J.; Negoita, F.; Novak, J.; Oberstedt, S.; Oberstedt, A.; Panebianco, S.; Perrot, L.; Plompen, A. J. M.; Pomp, S.; Ramillon, J. M.; Ridikas, D.; Rossé, B.; Rudolf, G.; Serot, O.; Simakov, S. P.; Simeckova, E.; Smith, A. G.; Sublet, J. C.; Taieb, J.; Tassan-Got, L.; Tarrio, D.; Takibayev, A.; Thfoin, I.; Tsekhanovich, I.; Varignon, C.

2014-05-01

The Neutrons For Science (NFS) facility is a component of SPIRAL-2 laboratory under construction at Caen (France). SPIRAL-2 is dedicated to the production of high intensity Radioactive Ions Beams (RIB). It is based on a high-power linear accelerator (LINAG) to accelerate deuterons beams in order to produce neutrons by breakup reactions on a C converter. These neutrons will induce fission in 238U for production of radioactive isotopes. Additionally to the RIB production, the proton and deuteron beams delivered by the accelerator will be used in the NFS facility. NFS is composed of a pulsed neutron beam and irradiation stations for cross-section measurements and material studies. The beams delivered by the LINAG will allow producing intense neutron beams in the 100 keV-40 MeV energy range with either a continuous or quasi-mono-energetic spectrum. At NFS available average fluxes will be up to 2 orders of magnitude higher than those of other existing time-of-flight facilities in the 1 MeV - 40 MeV range. NFS will be a very powerful tool for fundamental physics and application related research in support of the transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors. The facility and its characteristics are described, and several examples of the first potential experiments are presented.

Heavy ion beams from an Alphatross source for use in calibration and testing of diagnostics

NASA Astrophysics Data System (ADS)

Ward, R. J.; Brown, G. M.; Ho, D.; Stockler, B. F. O. F.; Freeman, C. G.; Padalino, S. J.; Regan, S. P.

2016-10-01

Ion beams from the 1.7 MV Pelletron Accelerator at SUNY Geneseo have been used to test and calibrate many inertial confinement fusion (ICF) diagnostics and high energy density physics (HEDP) diagnostics used at the Laboratory for Laser Energetics (LLE). The ion source on this accelerator, a radio-frequency (RF) alkali-metal charge exchange source called an Alphatross, is designed to produce beams of hydrogen and helium isotopes. There is interest in accelerating beams of carbon, oxygen, argon, and other heavy ions for use in testing several diagnostics, including the Time Resolved Tandem Faraday Cup (TRTF). The feasibility of generating these heavy ion beams using the Alphatross source will be reported. Small amounts of various gases are mixed into the helium plasma in the ion source bottle. A velocity selector is used to allow the desired ions to pass into the accelerator. As the heavy ions pass through the stripper canal of the accelerator, they emerge in a variety of charge states. The energy of the ion beam at the high-energy end of the accelerator will vary as a function of the charge state, however the maximum energy deliverable to target is limited by the maximum achievable magnetic field produced by the accelerator's steering magnet. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

Accurate Measurement of Velocity and Acceleration of Seismic Vibrations near Nuclear Power Plants

NASA Astrophysics Data System (ADS)

Arif, Syed Javed; Imdadullah; Asghar, Mohammad Syed Jamil

In spite of all prerequisite geological study based precautions, the sites of nuclear power plants are also susceptible to seismic vibrations and their consequent effects. The effect of the ongoing nuclear tragedy in Japan caused by an earthquake and its consequent tsunami on March 11, 2011 is currently beyond contemplations. It has led to a rethinking on nuclear power stations by various governments around the world. Therefore, the prediction of location and time of large earthquakes has regained a great importance. The earth crust is made up of several wide, thin and rigid plates like blocks which are in constant motion with respect to each other. A series of vibrations on the earth surface are produced by the generation of elastic seismic waves due to sudden rupture within the plates during the release of accumulated strain energy. The range of frequency of seismic vibrations is from 0 to 10 Hz. However, there appears a large variation in magnitude, velocity and acceleration of these vibrations. The response of existing or conventional methods of measurement of seismic vibrations is very slow, which is of the order of tens of seconds. A systematic and high resolution measurement of velocity and acceleration of these vibrations are useful to interpret the pattern of waves and their anomalies more accurately, which are useful for the prediction of an earthquake. In the proposed work, a fast rotating magnetic field (RMF) is used to measure the velocity and acceleration of seismic vibrations in the millisecond range. The broad spectrum of pulses within one second range, measured by proposed method, gives all possible values of instantaneous velocity and instantaneous acceleration of the seismic vibrations. The spectrum of pulses in millisecond range becomes available which is useful to measure the pattern of fore shocks to predict the time and location of large earthquakes more accurately. Moreover, instead of average, the peak values of these quantities are helpful in proper design of earthquake resistant nuclear power plants, buildings and structures. The proposed measurement scheme is successfully tested with a microprocessor based rocking vibration arrangement and the overall performance is recorded at dynamic conditions.

Single event burnout of high-power diodes

NASA Astrophysics Data System (ADS)

Maier, K. H.; Denker, A.; Voss, P.; Becker, H.-W.

1998-12-01

High-power diodes might be damaged by a single particle of cosmic radiation. This particle has first to produce a secondary nucleus, that ionizes more densely, through a nuclear reaction with the silicon of the diode. A multiplication of the number of charge carriers, primarily produced by this nucleus, can occur and eventually lead to a break down. The onset of this charge carrier multiplication is investigated with accelerated heavy ions under well controlled conditions. Clear trends are revealed, but the process is not yet understood.

Thermal and epithermal neutron fluence rate gradient measurements by PADC detectors in LINAC radiotherapy treatments-field

NASA Astrophysics Data System (ADS)

Barrera, M. T.; Barros, H.; Pino, F.; Dávila, J.; Sajo-Bohus, L.

2015-07-01

LINAC VARIAN 2100 is where energetic electrons produce Bremsstrahlung radiation, with energies above the nucleon binding energy (E≈5.5MeV). This radiation induce (γ,n) and (e,e'n) reactions mainly in the natural tungsten target material (its total photoneutron cross section is about 4000 mb in a energy range from 9-17 MeV). These reactions may occur also in other components of the system (e.g. multi leaf collimator). During radiation treatment the human body may receive an additional dose inside and outside the treated volume produced by the mentioned nuclear reactions. We measured the neutron density at the treatment table using nuclear track detectors (PADC-NTD). These covered by a boron-converter are employed, including a cadmium filter, to determine the ratio between two groups of neutron energy, i.e. thermal and epithermal. The PADC-NTD detectors were exposed to the radiation field at the iso-center during regular operation of the accelerator. Neutron are determined indirectly by the converting reaction 10B(n,α)7Li the emerging charged particle leave their kinetic energy in the PADC forming a latent nuclear track, enlarged by chemical etching (6N, NaOH, 70°C). Track density provides information on the neutron density through calibration coefficient (˜1.6 104 neutrons /track) obtained by a californium source. We report the estimation of the thermal and epithermal neutron field and its gradient for photoneutrons produced in radiotherapy treatments with 18 MV linear accelerators. It was obsered that photoneutron production have higher rate at the iso-center.

Accelerator-driven transmutation of spent fuel elements

DOEpatents

Venneri, Francesco; Williamson, Mark A.; Li, Ning

2002-01-01

An apparatus and method is described for transmuting higher actinides, plutonium and selected fission products in a liquid-fuel subcritical assembly. Uranium may also be enriched, thereby providing new fuel for use in conventional nuclear power plants. An accelerator provides the additional neutrons required to perform the processes. The size of the accelerator needed to complete fuel cycle closure depends on the neutron efficiency of the supported reactors and on the neutron spectrum of the actinide transmutation apparatus. Treatment of spent fuel from light water reactors (LWRs) using uranium-based fuel will require the largest accelerator power, whereas neutron-efficient high temperature gas reactors (HTGRs) or CANDU reactors will require the smallest accelerator power, especially if thorium is introduced into the newly generated fuel according to the teachings of the present invention. Fast spectrum actinide transmutation apparatus (based on liquid-metal fuel) will take full advantage of the accelerator-produced source neutrons and provide maximum utilization of the actinide-generated fission neutrons. However, near-thermal transmutation apparatus will require lower standing

26Al production: The Allende meteorite (Chihuahua) stellar nucleosynthesis and solar models

NASA Astrophysics Data System (ADS)

Araujo-Escalona, V.; Andrade, E.; Barrón-Palos, L.; Canto, C.; Favela, F.; Huerta, A.; de Lucio, O.; Ortiz, M. E.; Solís, C.; Chávez, E.

2015-07-01

In 1969 a meteorite fell near the small town of Allende, state of Chihuahua in the north of Mexico. Its study yielded information that changed the current understanding of the solar model. In particular traces of 26Al were found. Abundances of that isotope had been seen in the universe and were related to regions of active heavy nucleosynthesis. Its presence on the solar system was unexpected. It is now understood that cosmic rays induce nuclear reactions on materials to produce 26Al, on Earth this is well known and it is the basis of many environmental studies, so it is not only the product of some high metalicity star collapse. Taking advantage of the recently reinforced laboratory infrastructure of the Instituto de Física, at UNAM in Mexico City, we proposed to measure the cross section for 26Al production via some of the most likely reactions, from the nuclear physics point of view (highest Q-values). In this paper the study of the 28Si(d,α)26 Al nuclear reaction is shown. A target is prepared by a mixture of silicon and aluminum powders. It is irradiated with a deuteron beam (≈1 µA current) at the MV CN-Van de Graaff accelerator laboratory. The number of projectiles is deduced by Rutherford Backscattering Spectrometry (RBS). The produced 26Al nuclei are then counted at the Accelerator Mass Spectrometry Laboratory.

Photonuclear Production of Medical Isotopes

NASA Astrophysics Data System (ADS)

Weinandt, Nick

2011-10-01

Every year, more than 20 million people in the United States receive a nuclear medicine procedure. Many of the isotopes needed for these procedures are under-produced. Suppliers of the isotopes are usually located outside the United States, which presents a problem when the desired isotopes have short half-lives. Linear accelerators were investigated as a possible method of meeting isotope demand. Linear accelerators are cheaper, safer, and have lower decommissioning costs compared to nuclear reactors. By using (γ,p) reactions, the desired isotope can be separated from the target material due to the different chemical nature of each isotope. Isotopes investigated were Cu-67, In-111, and Lu-111. Using the results the photon flux Monte Carlo simulations, the expected activity of isotopes can be calculated. After samples were irradiated, a high purity germanium detector and signal processing apparatus were used to count the samples. The activity at the time of irradiation stop was then calculated. The uses of medical isotopes will also be presented. Thanks to Idaho State University, the Idaho Accelerator Center, and the National Science Foundation for supporting the research.

Study of 232Th(n, γ) and 232Th(n,f) reaction rates in a graphite moderated spallation neutron field produced by 1.6 GeV deuterons on lead target

NASA Astrophysics Data System (ADS)

Asquith, N. L.; Hashemi-Nezhad, S. R.; Westmeier, W.; Zhuk, I.; Tyutyunnikov, S.; Adam, J.

2015-02-01

The Gamma-3 assembly of the Joint Institute for Nuclear Research (JINR), Dubna, Russia is designed to emulate the neutron spectrum of a thermal Accelerator Driven System (ADS). It consists of a lead spallation target surrounded by reactor grade graphite. The target was irradiated with 1.6 GeV deuterons from the Nuclotron accelerator and the neutron capture and fission rate of 232Th in several locations within the assembly were experimentally measured. 232Th is a proposed fuel for envisaged Accelerator Driven Systems and these two reactions are fundamental to the performance and feasibility of 232Th in an ADS. The irradiation of the Gamma-3 assembly was also simulated using MCNPX 2.7 with the INCL4 intra-nuclear cascade and ABLA fission/evaporation models. Good agreement between the experimentally measured and calculated reaction rates was found. This serves as a good validation for the computational models and cross section data used to simulate neutron production and transport of spallation neutrons within a thermal ADS.

HEATHER - HElium Ion Accelerator for RadioTHERapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, Jordan; Edgecock, Thomas; Green, Stuart

2017-05-01

A non-scaling fixed field alternating gradient (nsFFAG) accelerator is being designed for helium ion therapy. This facility will consist of 2 superconducting rings, treating with helium ions (He²⁺ ) and image with hydrogen ions (H + 2 ). Currently only carbon ions are used to treat cancer, yet there is an increasing interest in the use of lighter ions for therapy. Lighter ions have reduced dose tail beyond the tumour compared to carbon, caused by low Z secondary particles produced via inelastic nuclear reactions. An FFAG approach for helium therapy has never been previously considered. Having demonstrated isochronous acceleration frommore » 0.5 MeV to 900 MeV, we now demonstrate the survival of a realistic beam across both stages.« less

Beam commissioning for a superconducting proton linac

NASA Astrophysics Data System (ADS)

Wang, Zhi-Jun; He, Yuan; Jia, Huan; Dou, Wei-ping; Chen, Wei-long; Zhang, X. L.; Liu, Shu-hui; Feng, Chi; Tao, Yue; Wang, Wang-sheng; Wu, Jian-qiang; Zhang, Sheng-hu; Zhao, Hong-Wei

2016-12-01

To develop the next generation of safe and cleaner nuclear energy, the accelerator-driven subcritical (ADS) system emerges as one of the most attractive technologies. It will be able to transmute the long-lived transuranic radionuclides produced in the reactors of today's nuclear power plants into shorter-lived ones, and also it will provide positive energy output at the same time. The prototype of the Chinese ADS (C-ADS) proton accelerator comprises two injectors and a 1.5 GeV, 10 mA continuous wave (CW) superconducting main linac. The injector scheme II at the C-ADS demo facility inside the Institute of Modern Physics is a 10 MeV CW superconducting linac with a designed beam current of 10 mA, which includes an ECR ion source, a low-energy beam transport line, a 162.5 MHz radio frequency quadrupole accelerator, a medium-energy beam transport line, and a superconducting half wave resonator accelerator section. This demo facility has been successfully operating with an 11 mA, 2.7 MeV CW beam and a 3.9 mA, 4.3 MeV CW beam at different times and conditions since June 2014. The beam power has reached 28 kW, which is the highest record for the same type of linear accelerators. In this paper, the parameters of the test injector II and the progress of the beam commissioning are reported.

How to Produce a Reactor Neutron Spectrum Using a Proton Accelerator

DOE PAGES

Burns, Kimberly A.; Wootan, David W.; Gates, Robert O.; ...

2015-06-18

A method for reproducing the neutron energy spectrum present in the core of an operating nuclear reactor using an engineered target in an accelerator proton beam is proposed. The protons interact with a target to create neutrons through various (p,n) type reactions. Spectral tailoring of the emitted neutrons can be used to modify the energy of the generated neutron spectrum to represent various reactor spectra. Through the use of moderators and reflectors, the neutron spectrum can be modified to reproduce many different spectra of interest including spectra in small thermal test reactors, large pressurized water reactors, and fast reactors. Themore » particular application of this methodology is the design of an experimental approach for using an accelerator to measure the betas produced during fission to be used to reduce uncertainties in the interpretation of reactor antineutrino measurements. This approach involves using a proton accelerator to produce a neutron field representative of a power reactor, and using this neutron field to irradiate fission foils of the primary isotopes contributing to fission in the reactor, creating unstable, neutron rich fission products that subsequently beta decay and emit electron antineutrinos. A major advantage of an accelerator neutron source over a neutron beam from a thermal reactor is that the fast neutrons can be slowed down or tailored to approximate various power reactor spectra. An accelerator based neutron source that can be tailored to match various reactor neutron spectra provides an advantage for control in studying how changes in the neutron spectra affect parameters such as the resulting fission product beta spectrum.« less

High energy neutrinos and gamma-ray emission from supernovae in compact star clusters

NASA Astrophysics Data System (ADS)

Bykov, A. M.; Ellison, D. C.; Gladilin, P. E.; Osipov, S. M.

2017-01-01

Compact clusters of young massive stars are observed in the Milky Way and in starburst galaxies. The compact clusters with multiple powerful winds of young massive stars and supernova shocks are favorable sites for high-energy particle acceleration. We argue that expanding young supernova (SN) shells in compact stellar clusters can be very efficient PeV CR accelerators. At a stage when a supernova shock is colliding with collective fast winds from massive stars in a compact cluster the Fermi mechanism allows particle acceleration to energies well above the standard limits of diffusive shock acceleration in an isolated SNR. The energy spectrum of protons in such an accelerator is a hard power-law with a broad spectral upturn above TeV before a break at multi-PeV energies, providing a large energy flux in the high-energy end of the spectrum. The acceleration stage in the colliding shock flow lasts for a few hundred years after the supernova explosion producing high-energy CRs that escape the accelerator and diffuse through the ambient matter producing γ-rays and neutrinos in inelastic nuclear collisions. In starburst galaxies a sizeable fraction of core collapse supernovae is expected to occur in compact star clusters and therefore their high energy gamma-ray and neutrino spectra in the PeV energy regime may differ strongly from that of our Galaxy. To test the model with individual sources we briefly discuss the recent H.E.S.S. detections of gamma-rays from two potential candidate sources, Westerlund 1 and HESS J1806-204 in the Milky Way. We argue that this model of compact star clusters, with typical parameters, could produce a neutrino flux sufficient to explain a fraction of the recently detected IceCube South Pole Observatory neutrinos.

Nuclear Methods for Transmutation of Nuclear Waste: Problems, Perspextives, Cooperative Research - Proceedings of the International Workshop

NASA Astrophysics Data System (ADS)

Khankhasayev, Zhanat B.; Kurmanov, Hans; Plendl, Mikhail Kh.

1996-12-01

The Table of Contents for the full book PDF is as follows: * Preface * I. Review of Current Status of Nuclear Transmutation Projects * Accelerator-Driven Systems — Survey of the Research Programs in the World * The Los Alamos Accelerator-Driven Transmutation of Nuclear Waste Concept * Nuclear Waste Transmutation Program in the Czech Republic * Tentative Results of the ISTC Supported Study of the ADTT Plutonium Disposition * Recent Neutron Physics Investigations for the Back End of the Nuclear Fuel Cycle * Optimisation of Accelerator Systems for Transmutation of Nuclear Waste * Proton Linac of the Moscow Meson Factory for the ADTT Experiments * II. Computer Modeling of Nuclear Waste Transmutation Methods and Systems * Transmutation of Minor Actinides in Different Nuclear Facilities * Monte Carlo Modeling of Electro-nuclear Processes with Nonlinear Effects * Simulation of Hybrid Systems with a GEANT Based Program * Computer Study of 90Sr and 137Cs Transmutation by Proton Beam * Methods and Computer Codes for Burn-Up and Fast Transients Calculations in Subcritical Systems with External Sources * New Model of Calculation of Fission Product Yields for the ADTT Problem * Monte Carlo Simulation of Accelerator-Reactor Systems * III. Data Basis for Transmutation of Actinides and Fission Products * Nuclear Data in the Accelerator Driven Transmutation Problem * Nuclear Data to Study Radiation Damage, Activation, and Transmutation of Materials Irradiated by Particles of Intermediate and High Energies * Radium Institute Investigations on the Intermediate Energy Nuclear Data on Hybrid Nuclear Technologies * Nuclear Data Requirements in Intermediate Energy Range for Improvement of Calculations of ADTT Target Processes * IV. Experimental Studies and Projects * ADTT Experiments at the Los Alamos Neutron Science Center * Neutron Multiplicity Distributions for GeV Proton Induced Spallation Reactions on Thin and Thick Targets of Pb and U * Solid State Nuclear Track Detector and Radiochemical Studies on the Transmutation of Nuclei Using Relativistic Heavy Ions * Experimental and Theoretical Study of Radionuclide Production on the Electronuclear Plant Target and Construction Materials Irradiated by 1.5 GeV and 130 MeV Protons * Neutronics and Power Deposition Parameters of the Targets Proposed in the ISTC Project 17 * Multicycle Irradiation of Plutonium in Solid Fuel Heavy-Water Blanket of ADS * Compound Neutron Valve of Accelerator-Driven System Sectioned Blanket * Subcritical Channel-Type Reactor for Weapon Plutonium Utilization * Accelerator Driven Molten-Fluoride Reactor with Modular Heat Exchangers on PB-BI Eutectic * A New Conception of High Power Ion Linac for ADTT * Pions and Accelerator-Driven Transmutation of Nuclear Waste? * V. Problems and Perspectives * Accelerator-Driven Transmutation Technologies for Resolution of Long-Term Nuclear Waste Concerns * Closing the Nuclear Fuel-Cycle and Moving Toward a Sustainable Energy Development * Workshop Summary * List of Participants

The founding of CEBAF, 1979 to 1987

DOE Office of Scientific and Technical Information (OSTI.GOV)

C. Westfall

1995-02-01

In early 1979 a group of physicists assembled at the University of Virginia (UVa) for a conference entitled ''Future Possibilities for Electron Accelerators.'' In the audience sat an organizer of the conference, UVa professor James McCarthy. While listening to talks by Gregory Loew of the Stanford Linear Accelerator Center (SLAC) and Roger Servranckx of the University of Saskatchewan, McCarthy got very excited. Both discussed new approaches to producing an almost continuous stream of electrons with improved designs for pulse stretcher rings that could be built within a reasonable budget. McCarthy saw the possibility of realizing a dream. This dream hadmore » its origins in the 1950s, when Robert Hofstadter, McCarthy's thesis advisor, made groundbreaking discoveries at Stanford's High Energy Physics Laboratory (HEPL) about the internal structure of nuclei and nucleons. For these experiments Hofstadter used Mark III, the most advanced in a series of electron accelerators designed by William Hansen, who pioneered methods of high frequency acceleration of electrons. The work by Hofstadter and Hansen led to two productive lines of inquiry. One group of researchers studied particle production using electrons at higher energies, which led to the construction in the 1960s of SLAC at Stanford. Another group of researchers, which included McCarthy, investigated nuclear structure with more modest increases in energy accompanied by increases in the duty factor of the electron beam. This line of inquiry, electro-nuclear physics, led in the 1960s and 1970s to a succession of accelerators, including a $7.2 million high duty factor 400 MeV linear accelerator (linac) completed in 1972 at the Bates Laboratory at the Massachusetts Institute of Technology (Bates-MIT), and ambitious attempts to develop untried technologies to further boost energy and duty factor, most notably the effort to develop superconducting radiofrequency (srf) accelerating technology at HEPL. By 1979 electro-nuclear physics had attracted a considerable following. The growing electro-nuclear physics community was eager to find a scheme to permit virtually continuous acceleration, which would greatly improve the capability of performing coincidence experiments. In the words of the UVa conference proceedings, this experimental capability promised to open entire new areas of nuclear physics. Convinced that he could be the one to design the necessary groundbreaking machine after hearing the ideas of Loew and Servranckx, McCarthy began gathering a small accelerator building team. Against all odds, McCarthy's pipe dream resulted in the construction of a major accelerator laboratory, the Continuous Electron Beam Accelerator Facility (CEBAF). The founding of CEBAF is a tale of luck, perseverance, the triumph of flexible amateurism over rigid professionalism, and ironically, the potential of amateurs when supported by a thoroughly professional international network with well-defined methods for organizing and building accelerators. The CEBAF tale also has a surprise ending, for at the last minute, McCarthy's pipe dream was radically transformed by Hermann Grunder, who would direct the construction of the project. The twists and turns of this tale reveal many lessons about what aids and what detracts from the success of a large, federally sponsored scientific project.« less

Radiation Generation from Ultra Intense Laser Plasma Interactions with Solid Density Plasmas for Active Interrogation of Nuclear Materials

NASA Astrophysics Data System (ADS)

Zulick, Calvin Andrew

The development of short pulse high power lasers has led to interest in laser based particle accelerators. Laser produced plasmas have been shown to support quasi-static TeV/m acceleration gradients which are more than four orders of magnitude stronger than conventional accelerators. These high gradients have the potential to allow compact particle accelerators for active interrogation of nuclear material. In order to better understand this application, several experiments have been conducted at the HERCULES and Lambda Cubed lasers as the Center for Ultrafast Optical Science at the University of Michigan. Electron acceleration and bremsstrahlung generation were studied on the Lambda Cubed laser. The scaling of the intensity, angular, and material dependence of bremsstrahlung radiation from an intense (I > 10 18 W/cm2 ) laser-solid interaction has been characterized at energies between 100 keV and 1 MeV. These were the first high resolution (lambda / d lambda > 100) measurements of bremsstrahlung photons from a relativistic laser plasma interaction. The electron populations and bremsstrahlung temperatures were modeled in the particle-in-cell code OSIRIS and the Monte Carlo code MCNPX and were in good agreement with the experimental results. Proton acceleration was studied on the HERCULES laser. The effect of three dimensional perturbations of electron sheaths on proton acceleration was investigated through the use of foil, grid, and wire targets. Hot electron density, as measured with an imaging Cu Kalpha crystal, increased as the target surface area was reduced and was correlated to an increase in the temperature of the accelerated proton beam. Additionally, experiments at the HERCULES laser facility have produced directional neutron beams with energies up to 16.8 (+/-0.3) MeV using (d,n) and (p,n) reactions. Efficient (d,n) reactions required the selective acceleration of deuterons through the introduction of a deuterated plastic or cryogenically frozen D2O layer on the surface of a thin film target. The measured neutron yield was up to 1.0 (+/-0.5) x 107 neutrons/sr with a flux 6.2 (+/-3.7) times higher in the forward direction than at 90 degrees . This demonstrated that femtosecond lasers are capable of providing a time averaged neutron flux equivalent to commercial DD generators with the advantage of a directional beam with picosecond bunch duration.

INSTRUMENTS AND METHODS OF INVESTIGATION: Giant pulses of thermal neutrons in large accelerator beam dumps. Possibilities for experiments

NASA Astrophysics Data System (ADS)

Stavissky, Yurii Ya

2006-12-01

A short review is presented of the development in Russia of intense pulsed neutron sources for physical research — the pulsating fast reactors IBR-1, IBR-30, IBR-2 (Joint Institute for Nuclear Research, Dubna), and the neutron-radiation complex of the Moscow meson factory — the 'Troitsk Trinity' (RAS Institute for Nuclear Research, Troitsk, Moscow region). The possibility of generating giant neutron pulses in beam dumps of superhigh energy accelerators is discussed. In particular, the possibility of producing giant pulsed thermal neutron fluxes in modified beam dumps of the large hadron collider (LHD) under construction at CERN is considered. It is shown that in the case of one-turn extraction ov 7-TeV protons accumulated in the LHC main rings on heavy targets with water or zirconium-hydride moderators placed in the front part of the LHC graphite beam-dump blocks, every 10 hours relatively short (from ~100 µs) thermal neutron pulses with a peak flux density of up to ~1020 neutrons cm-2 s-1 may be produced. The possibility of applying such neutron pulses in physical research is discussed.

Production of Medical Isotopes with Electron Linacs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rotsch, D A; Alford, K.; Bailey, J. L.

Radioisotopes play important roles in numerous areas ranging from medical treatments to national security and basic research. Radionuclide production technology for medical applications has been pursued since the early 1900s both commercially and in nuclear science centers. Many medical isotopes are now in routine production and are used in day-to-day medical procedures. Despite these advancements, research is accelerating around the world to improve the existing production methodologies as well as to develop novel radionuclides for new medical appli-cations. Electron linear accelerators (linacs) represent a unique method for the production of radioisotopes. Even though the basic technology has been around formore » decades, only recently have electron linacs capable of producing photons with sufficient energy and flux for radioisotope production become available. Housed in Argonne Nation-al Laboratory’s Low Energy Accelerator Facility (LEAF) is a newly upgraded 55 MeV/25-kW electron linear ac-celerator, capable of producing a wide range of radioiso-topes. This talk will focus on the work being performed for the production of the medical isotopes 99Mo (99Mo/99mTc generator), 67Cu, and 47Sc.« less

Study of the Insulating Magnetic Field in an Accelerating Ion Diode

NASA Astrophysics Data System (ADS)

Kozlovsky, K. I.; Martynenko, A. S.; Vovchenko, E. D.; Lisovsky, M. I.; Isaev, A. A.

2017-12-01

The results of examination of the insulating magnetic field in an accelerating ion diode are presented. This field is produced in order to suppress the electron current and thus enhance the neutron yield of the D( d, n)3He nuclear reaction. The following two designs are discussed: a gas-filled diode with inertial electrostatic confinement of ions and a vacuum diode with a laser-plasma ion source and pulsed magnetic insulation. Although the insulating field of permanent magnets is highly nonuniform, it made it possible to extend the range of accelerating voltages to U = 200 kV and raise the neutron yield to Q = 107 in the first design. The nonuniform field structure is less prominent in the device with pulsed magnetic insulation, which demonstrated efficient deuteron acceleration with currents up to 1 kA at U = 400 kV. The predicted neutron yield is as high as 109 neutrons/pulse.

Benchmark experiment for the cross section of the 100Mo(p,2n)99mTc and 100Mo(p,pn)99Mo reactions

NASA Astrophysics Data System (ADS)

Takács, S.; Ditrói, F.; Aikawa, M.; Haba, H.; Otuka, N.

2016-05-01

As nuclear medicine community has shown an increasing interest in accelerator produced 99mTc radionuclide, the possible alternative direct production routes for producing 99mTc were investigated intensively. One of these accelerator production routes is based on the 100Mo(p,2n)99mTc reaction. The cross section of this nuclear reaction was studied by several laboratories earlier but the available data-sets are not in good agreement. For large scale accelerator production of 99mTc based on the 100Mo(p,2n)99mTc reaction, a well-defined excitation function is required to optimise the production process effectively. One of our recent publications pointed out that most of the available experimental excitation functions for the 100Mo(p,2n)99mTc reaction have the same general shape while their amplitudes are different. To confirm the proper amplitude of the excitation function, results of three independent experiments were presented (Takács et al., 2015). In this work we present results of a thick target count rate measurement of the Eγ = 140.5 keV gamma-line from molybdenum irradiated by Ep = 17.9 MeV proton beam, as an integral benchmark experiment, to prove the cross section data reported for the 100Mo(p,2n)99mTc and 100Mo(p,pn)99Mo reactions in Takács et al. (2015).

Reaction Studies With Light, Unstable Nuclei

NASA Astrophysics Data System (ADS)

Ernst Rehm, K.

2006-10-01

The availability of beams of exotic nuclei allows us for the first time to study in a terrestrial laboratory reactions, which occur in stellar explosions, such as Novae, Supernovae or X-ray bursts. In this talk I will present results from recent experiments performed with beams of light, unstable nuclei, which are produced via the in-flight technique at the ATLAs accelerator at Argonne. This work was supported by the US Department of Energy, Nuclear Physics Division, under contract No. W-31-109-ENG-38 and by the NSF Grant No. PHY-02-16783 (Joint Institute for Nuclear Astrophysics).

A system of {sup 99m}Tc production based on distributed electron accelerators and thermal separation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, R.G.; Christian, J.D.; Petti, D.A.

1999-04-01

A system has been developed for the production of {sup 99m}Tc based on distributed electron accelerators and thermal separation. The radioactive decay parent of {sup 99m}Tc, {sup 99}Mo, is produced from {sup 100}Mo by a photoneutron reaction. Two alternative thermal separation processes have been developed to extract {sup 99m}Tc. Experiments have been performed to verify the technical feasibility of the production and assess the efficiency of the extraction processes. A system based on this technology enables the economical supply of {sup 99m}Tc for a large nuclear pharmacy. Twenty such production centers distributed near major metropolitan areas could produce the entiremore » US supply of {sup 99m}Tc at a cost less than the current subsidized price.« less

Abnormal nuclear envelopes in the striatum and motor deficits in DYT11 myoclonus-dystonia mouse models.

PubMed

Yokoi, Fumiaki; Dang, Mai T; Zhou, Tong; Li, Yuqing

2012-02-15

DYT11 myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonic symptoms and caused by mutations in paternally expressed SGCE, which codes for ε-sarcoglycan. Paternally inherited Sgce heterozygous knock-out (KO) mice exhibit motor deficits and spontaneous myoclonus. Abnormal nuclear envelopes have been reported in cellular and mouse models of early-onset DYT1 generalized torsion dystonia; however, the relationship between the abnormal nuclear envelopes and motor symptoms are not clear. Furthermore, it is not known whether abnormal nuclear envelope exists in non-DYT1 dystonia. In the present study, abnormal nuclear envelopes in the striatal medium spiny neurons (MSNs) were found in Sgce KO mice. To analyze whether the loss of ε-sarcoglycan in the striatum alone causes abnormal nuclear envelopes, motor deficits or myoclonus, we produced paternally inherited striatum-specific Sgce conditional KO (Sgce sKO) mice and analyzed their phenotypes. Sgce sKO mice exhibited motor deficits in both beam-walking and accelerated rotarod tests, while they did not exhibit abnormal nuclear envelopes, alteration in locomotion, or myoclonus. The results suggest that the loss of ε-sarcoglycan in the striatum contributes to motor deficits, while it alone does not produce abnormal nuclear envelopes or myoclonus. Development of therapies targeting the striatum to compensate for the loss of ε-sarcoglycan function may rescue the motor deficits in DYT11 M-D patients.

Transmutation of Radioactive Nuclear Waste — Present Status and Requirement for the Problem-Oriented Nuclear Database: Approach to Scheduling the Experiments (Reactor, Target, Blanket)

NASA Astrophysics Data System (ADS)

Artisyuk, V.; Ignatyuk, A.; Korovin, Yu.; Lopatkin, A.; Matveenko, I.; Stankovskiy, A.; Titarenko, Yu.

2005-05-01

Transmutation of nuclear wastes (Minor Actinides and Long-Lived Fission Products) remains an important option to reduce the burden of high-level waste on final waste disposal in deep geological structures. Accelerator-Driven Systems (ADS) are considered as possible candidates to perform transmutation due to their subcritical operation mode that eliminates some of the serious safety penalties unavoidable in critical reactors. Specific requirements to nuclear data necessary for ADS transmutation analysis is the main subject of the ISTC Project ♯2578 which started in 2004 to identify the areas of research priorities in the future. The present paper gives a summary of ongoing project stressing the importance of nuclear data for blanket performance (reactivity behavior with associated safety characteristics) and uncertainties that affect characteristics of neutron producing target.

Thermal and epithermal neutron fluence rate gradient measurements by PADC detectors in LINAC radiotherapy treatments-field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barrera, M. T., E-mail: mariate9590@gmail.com; Barros, H.; Pino, F.

2015-07-23

LINAC VARIAN 2100 is where energetic electrons produce Bremsstrahlung radiation, with energies above the nucleon binding energy (E≈5.5MeV). This radiation induce (γ,n) and (e,e’n) reactions mainly in the natural tungsten target material (its total photoneutron cross section is about 4000 mb in a energy range from 9-17 MeV). These reactions may occur also in other components of the system (e.g. multi leaf collimator). During radiation treatment the human body may receive an additional dose inside and outside the treated volume produced by the mentioned nuclear reactions. We measured the neutron density at the treatment table using nuclear track detectors (PADC-NTD). Thesemore » covered by a boron-converter are employed, including a cadmium filter, to determine the ratio between two groups of neutron energy, i.e. thermal and epithermal. The PADC-NTD detectors were exposed to the radiation field at the iso-center during regular operation of the accelerator. Neutron are determined indirectly by the converting reaction {sup 10}B(n,α){sup 7}Li the emerging charged particle leave their kinetic energy in the PADC forming a latent nuclear track, enlarged by chemical etching (6N, NaOH, 70°C). Track density provides information on the neutron density through calibration coefficient (∼1.6 10{sup 4} neutrons /track) obtained by a californium source. We report the estimation of the thermal and epithermal neutron field and its gradient for photoneutrons produced in radiotherapy treatments with 18 MV linear accelerators. It was obsered that photoneutron production have higher rate at the iso-center.« less

Overview of Mono-Energetic Gamma-Ray Sources and Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartemann, Fred; /LLNL, Livermore; Albert, Felicie

2012-06-25

Recent progress in accelerator physics and laser technology have enabled the development of a new class of tunable gamma-ray light sources based on Compton scattering between a high-brightness, relativistic electron beam and a high intensity laser pulse produced via chirped-pulse amplification (CPA). A precision, tunable Mono-Energetic Gamma-ray (MEGa-ray) source driven by a compact, high-gradient X-band linac is currently under development and construction at LLNL. High-brightness, relativistic electron bunches produced by an X-band linac designed in collaboration with SLAC NAL will interact with a Joule-class, 10 ps, diode-pumped CPA laser pulse to generate tunable {gamma}-rays in the 0.5-2.5 MeV photon energymore » range via Compton scattering. This MEGaray source will be used to excite nuclear resonance fluorescence in various isotopes. Applications include homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. The source design, key parameters, and current status are presented, along with important applications, including nuclear resonance fluorescence.« less

Particle acceleration on a chip: A laser-driven micro-accelerator for research and industry

NASA Astrophysics Data System (ADS)

Yoder, R. B.; Travish, G.

2013-03-01

Particle accelerators are conventionally built from radio-frequency metal cavities, but this technology limits the maximum energy available and prevents miniaturization. In the past decade, laser-powered acceleration has been intensively studied as an alternative technology promising much higher accelerating fields in a smaller footprint and taking advantage of recent advances in photonics. Among the more promising approaches are those based on dielectric field-shaping structures. These ``dielectric laser accelerators'' (DLAs) scale with the laser wavelength employed and can be many orders of magnitude smaller than conventional accelerators; DLAs may enable the production of high-intensity, ultra-short relativistic electron bunches in a chip-scale device. When combined with a high- Z target or an optical-period undulator, these systems could produce high-brilliance x-rays from a breadbox-sized device having multiple applications in imaging, medicine, and homeland security. In our research program we have developed one such DLA, the Micro-Accelerator Platform (MAP). We describe the fundamental physics, our fabrication and testing program, and experimental results to date, along with future prospects for MAP-based light-sources and some remaining challenges. Supported in part by the Defense Threat Reduction Agency and National Nuclear Security Administration.

The Four Lives of a Nuclear Accelerator

NASA Astrophysics Data System (ADS)

Wiescher, Michael

2017-06-01

Electrostatic accelerators have emerged as a major tool in research and industry in the second half of the twentieth century. In particular in low energy nuclear physics they have been essential for addressing a number of critical research questions from nuclear structure to nuclear astrophysics. This article describes this development on the example of a single machine which has been used for nearly sixty years at the forefront of scientific research in nuclear physics. The article summarizes the concept of electrostatic accelerators and outlines how this accelerator developed from a bare support function to an independent research tool that has been utilized in different research environments and institutions and now looks forward to a new life as part of the experiment CASPAR at the 4,850" level of the Sanford Underground Research Facility.

A high brightness proton injector for the Tandetron accelerator at Jožef Stefan Institute

NASA Astrophysics Data System (ADS)

Pelicon, Primož; Podaru, Nicolae C.; Vavpetič, Primož; Jeromel, Luka; Ogrinc Potocnik, Nina; Ondračka, Simon; Gottdang, Andreas; Mous, Dirk J. M.

2014-08-01

Jožef Stefan Institute recently commissioned a high brightness H- ion beam injection system for its existing tandem accelerator facility. Custom developed by High Voltage Engineering Europa, the multicusp ion source has been tuned to deliver at the entrance of the Tandetron™ accelerator H- ion beams with a measured brightness of 17.1 A m-2 rad-2 eV-1 at 170 μA, equivalent to an energy normalized beam emittance of 0.767 π mm mrad MeV1/2. Upgrading the accelerator facility with the new injection system provides two main advantages. First, the high brightness of the new ion source enables the reduction of object slit aperture and the reduction of acceptance angle at the nuclear microprobe, resulting in a reduced beam size at selected beam intensity, which significantly improves the probe resolution for micro-PIXE applications. Secondly, the upgrade strongly enhances the accelerator up-time since H and He beams are produced by independent ion sources, introducing a constant availability of 3He beam for fusion-related research with NRA. The ion beam particle losses and ion beam emittance growth imply that the aforementioned beam brightness is reduced by transport through the ion optical system. To obtain quantitative information on the available brightness at the high-energy side of the accelerator, the proton beam brightness is determined in the nuclear microprobe beamline. Based on the experience obtained during the first months of operation for micro-PIXE applications, further necessary steps are indicated to obtain optimal coupling of the new ion source with the accelerator to increase the normalized high-energy proton beam brightness at the JSI microprobe, currently at 14 A m-2 rad-2 eV-1, with the output current at 18% of its available maximum.

Topical applications of resonance internal conversion in laser produced plasma

NASA Astrophysics Data System (ADS)

Karpeshin, F. F.

2007-04-01

Physical aspects of resonance effects arising in plasma due to interactions of nuclei with the electrons are considered. Among them are resonance conversion (TEEN) and the reverse process of NEET. These processes are of great importance for pumping the excited nuclear states (isomers) and for accelerating their decay. Experiment is discussed on studying the unique 3.5-eV 229m Th nuclide.

Measurement of high energy neutrons via Lu(n,xn) reactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henry, E.A.; Becker, J.A.; Archer, D.E.

High energy neutrons can be assayed by the use of the nuclear diagnostic material lutetium. We are measuring the (n,xn) cross sections for natural lutetium in order to develop it as a detector material. We are applying lutetium to diagnose the high energy neutrons produced in test target/blanket systems appropriate for the Accelerator Production of Tritium Project. 3 refs., 5 figs., 1 tab.

236U measurement with accelerator mass spectrometry at CIAE

NASA Astrophysics Data System (ADS)

Wang, Xianggao; Jiang, Shan; He, Ming; Dong, Kejun; Wang, Wei; Li, Chaoli; He, Guozhu; Li, Shizhuo; Gong, Jie; Lu, Liyuan; Wu, Shaoyong

2010-07-01

236U is a long-lived radioactive isotope which is produced principally by thermal neutron capture on 235U. 236U may be potentially applied in geological research and nuclear safeguards. Accelerator mass spectrometry is presently the most sensitive technique for the measurement of 236U and a measurement method for long-lived heavy ion 236U has been developed. The set-up uses a dedicated injector and the newly proposed 208Pb 16O2- molecular ions for the simulation of 236U ion transport. A sensitivity of lower than 10 -10 has been achieved for the isotopic ratio 236U/ 238U in present work.

{sup 26}Al production: The Allende meteorite (Chihuahua) stellar nucleosynthesis and solar models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Araujo-Escalona, V.; Andrade, E.; Barrón-Palos, L.

2015-07-23

In 1969 a meteorite fell near the small town of Allende, state of Chihuahua in the north of Mexico. Its study yielded information that changed the current understanding of the solar model. In particular traces of {sup 26}Al were found. Abundances of that isotope had been seen in the universe and were related to regions of active heavy nucleosynthesis. Its presence on the solar system was unexpected. It is now understood that cosmic rays induce nuclear reactions on materials to produce {sup 26}Al, on Earth this is well known and it is the basis of many environmental studies, so itmore » is not only the product of some high metalicity star collapse. Taking advantage of the recently reinforced laboratory infrastructure of the Instituto de Física, at UNAM in Mexico City, we proposed to measure the cross section for {sup 26}Al production via some of the most likely reactions, from the nuclear physics point of view (highest Q-values). In this paper the study of the {sup 28}Si(d,α){sup 26} Al nuclear reaction is shown. A target is prepared by a mixture of silicon and aluminum powders. It is irradiated with a deuteron beam (≈1 µA current) at the MV CN-Van de Graaff accelerator laboratory. The number of projectiles is deduced by Rutherford Backscattering Spectrometry (RBS). The produced {sup 26}Al nuclei are then counted at the Accelerator Mass Spectrometry Laboratory.« less

APPARATUS FOR MEASURING NEUTRON CROSS SECTIONS

DOEpatents

Cranberg, L.

1959-07-14

An apparatus is described for analyzing the nuclear reaction products resulting from impingement of nuclear particles against a selected target material and automatically recording the number of reaction prcducts in selected energy levels. The target is bombarded by ions from a particle accelerator and the target potential is cyclicly varied over a particular energy range by a modulator. A nuclear reaction detector is lccated adjacent the target to produce pulses for each reaction product. The output from the detector and the modulator are coupled to a function sampler, for generating a pulse in respcnse to each detected event having an amplitude proportional to the amplitude of the instantaneous target potential. The later pulses are coupled to a multichannel analyzer, whereby nuclear reactions are recorded in appropriate channels of the analyzer in correspcndence with the magnitude of the energy of the impinging ions.

Identification of nuclear weapons

DOEpatents

Mihalczo, J.T.; King, W.T.

1987-04-10

A method and apparatus for non-invasively indentifying different types of nuclear weapons is disclosed. A neutron generator is placed against the weapon to generate a stream of neutrons causing fissioning within the weapon. A first detects the generation of the neutrons and produces a signal indicative thereof. A second particle detector located on the opposite side of the weapon detects the fission particles and produces signals indicative thereof. The signals are converted into a detected pattern and a computer compares the detected pattern with known patterns of weapons and indicates which known weapon has a substantially similar pattern. Either a time distribution pattern or noise analysis pattern, or both, is used. Gamma-neutron discrimination and a third particle detector for fission particles adjacent the second particle detector are preferably used. The neutrons are generated by either a decay neutron source or a pulled neutron particle accelerator.

Evidence for active galactic nucleus feedback in the broad absorption lines and reddening of MRK 231 {sup ,}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leighly, Karen M.; Baron, Eddie; Lucy, Adrian B.

2014-06-20

We present the first J-band spectrum of Mrk 231, which reveals a large He I* λ10830 broad absorption line with a profile similar to that of the well-known Na I broad absorption line. Combining this spectrum with optical and UV spectra from the literature, we show that the unusual reddening noted by Veilleux et al. is explained by a reddening curve like those previously used to explain low values of total-to-selective extinction in Type Ia supernovae. The nuclear starburst may be the origin and location of the dust. Spatially resolved emission in the broad absorption line trough suggests nearly fullmore » coverage of the continuum emission region. The broad absorption lines reveal higher velocities in the He I* lines (produced in the quasar-photoionized H II region) compared with the Na I and Ca II lines (produced in the corresponding partially ionized zone). Cloudy simulations show that a density increase is required between the H II and partially ionized zones to produce ionic column densities consistent with the optical and IR absorption line measurements and limits, and that the absorber lies ∼100 pc from the central engine. These results suggest that the He I* lines are produced in an ordinary quasar BAL wind that impacts upon, compresses, and accelerates the nuclear starburst's dusty effluent (feedback in action), and the Ca II and Na I lines are produced in this dusty accelerated gas. This unusual circumstance explains the rarity of Na I absorption lines; without the compression along our line of sight, Mrk 231 would appear as an ordinary iron low-ionization, broad absorption line quasar.« less

Jerome Lewis Duggan: A Nuclear Physicist and a Well-Known, Six-Decade Accelerator Application Conference (CAARI) Organizer

NASA Astrophysics Data System (ADS)

Del McDaniel, Floyd; Doyle, Barney L.

Jerry Duggan was an experimental MeV-accelerator-based nuclear and atomic physicist who, over the past few decades, played a key role in the important transition of this field from basic to applied physics. His fascination for and application of particle accelerators spanned almost 60 years, and led to important discoveries in the following fields: accelerator-based analysis (accelerator mass spectrometry, ion beam techniques, nuclear-based analysis, nuclear microprobes, neutron techniques); accelerator facilities, stewardship, and technology development; accelerator applications (industrial, medical, security and defense, and teaching with accelerators); applied research with accelerators (advanced synthesis and modification, radiation effects, nanosciences and technology); physics research (atomic and molecular physics, and nuclear physics); and many other areas and applications. Here we describe Jerry’s physics education at the University of North Texas (B. S. and M. S.) and Louisiana State University (Ph.D.). We also discuss his research at UNT, LSU, and Oak Ridge National Laboratory, his involvement with the industrial aspects of accelerators, and his impact on many graduate students, colleagues at UNT and other universities, national laboratories, and industry and acquaintances around the world. Along the way, we found it hard not to also talk about his love of family, sports, fishing, and other recreational activities. While these were significant accomplishments in his life, Jerry will be most remembered for his insight in starting and his industry in maintaining and growing what became one of the most diverse accelerator conferences in the world — the International Conference on the Application of Accelerators in Research and Industry, or what we all know as CAARI. Through this conference, which he ran almost single-handed for decades, Jerry came to know, and became well known by, literally thousands of atomic and nuclear physicists, accelerator engineers and vendors, medical doctors, cultural heritage experts... the list goes on and on. While thousands of his acquaintances already miss Jerry, this is being felt most by his family and us (B.D. and F.D.M).

Jerome Lewis Duggan: A Nuclear Physicist and a Well-Known, Six-Decade Accelerator Application Conference (CAARI) Organizer

NASA Astrophysics Data System (ADS)

Del McDaniel, Floyd; Doyle, Barney L.

Jerry Duggan was an experimental MeV-accelerator-based nuclear and atomic physicist who, over the past few decades, played a key role in the important transition of this field from basic to applied physics. His fascination for and application of particle accelerators spanned almost 60 years, and led to important discoveries in the following fields: accelerator-based analysis (accelerator mass spectrometry, ion beam techniques, nuclear-based analysis, nuclear microprobes, neutron techniques); accelerator facilities, stewardship, and technology development; accelerator applications (industrial, medical, security and defense, and teaching with accelerators); applied research with accelerators (advanced synthesis and modification, radiation effects, nanosciences and technology); physics research (atomic and molecular physics, and nuclear physics); and many other areas and applications. Here we describe Jerry's physics education at the University of North Texas (B. S. and M. S.) and Louisiana State University (Ph.D.). We also discuss his research at UNT, LSU, and Oak Ridge National Laboratory, his involvement with the industrial aspects of accelerators, and his impact on many graduate students, colleagues at UNT and other universities, national laboratories, and industry and acquaintances around the world. Along the way, we found it hard not to also talk about his love of family, sports, fishing, and other recreational activities. While these were significant accomplishments in his life, Jerry will be most remembered for his insight in starting and his industry in maintaining and growing what became one of the most diverse accelerator conferences in the world — the International Conference on the Application of Accelerators in Research and Industry, or what we all know as CAARI. Through this conference, which he ran almost single-handed for decades, Jerry came to know, and became well known by, literally thousands of atomic and nuclear physicists, accelerator engineers and vendors, medical doctors, cultural heritage experts... the list goes on and on. While thousands of his acquaintances already miss Jerry, this is being felt most by his family and us (B.D. and F.D.M).

Hermes 3

NASA Astrophysics Data System (ADS)

Hasti, D. E.; Ramirez, J. J.; Prestwich, K. R.; Sanford, T. W. L.; Hamil, R. A.

Hermes 3 is a major new gamma-ray simulator that is part of the Simulation Technology Laboratory Project. This accelerator will significantly improve the capability to evaluate the effects of gamma-ray radiation from nuclear weapons on weapons subsystems. This accelerator will be designed to produce 10(5)R, 5 x 10 to the 12th power R/S and 2 x 10 to the 20th power R/S(2) over a 500 sq cm area. The radiation dose will vary less than a factor of two over this area and less than a factor of four throughout a volume found by extending this surface 15 cm further from the gamma-ray converter. The minimum dose in this volume will be greater than or equal to 5 x 10 to the 4th power R. The accelerator will be designed with sufficient reliability and short enough turn-around time to produce more than 600 radiation pulses per year. In Hermes 3 the peak power in the beam is to be increased from 1.2 TW of Hermes 2 to 16 TW. Two techniques for achieving these high powers have been successfully developed. The first technique is a high current linear induction accelerator with several parallel beams. Experiments to evaluate this concept were done on the MABE accelerator. The second concept uses induction cavities and a magnetically insulated transmission line (MITL) to form a multi-terawatt voltage adder.

Accelerator-Reactor Coupling for Energy Production in Advanced Nuclear Fuel Cycles

NASA Astrophysics Data System (ADS)

Heidet, Florent; Brown, Nicholas R.; Haj Tahar, Malek

This article is a review of several accelerator-reactor interface issues and nuclear fuel cycle applications of accelerator-driven subcritical systems. The systems considered here have the primary goal of energy production, but that goal is accomplished via a specific application in various proposed nuclear fuel cycles, such as breed-and-burn of fertile material or burning of transuranic material. Several basic principles are reviewed, starting from the proton beam window including the target, blanket, reactor core, and up to the fuel cycle. We focus on issues of interest, such as the impact of the energy required to run the accelerator and associated systems on the potential electricity delivered to the grid. Accelerator-driven systems feature many of the constraints and issues associated with critical reactors, with the added challenges of subcritical operation and coupling to an accelerator. Reliable accelerator operation and avoidance of beam trips are critically important. One interesting challenge is measurement of blanket subcriticality level during operation. We also review the potential benefits of accelerator-driven systems in various nuclear fuel cycle applications. Ultimately, accelerator-driven subcritical systems with the goal of transmutation of transuranic material have lower 100,000-year radioactivity than a critical fast reactor with recycling of uranium and plutonium.

Determination of the energy transitions and half-lives of Rubidium nuclei

NASA Astrophysics Data System (ADS)

Biçer, Ahmet; Manisa, Kaan; Engin Çalık, Abdullah; Erdoğan, Mehmet; Şen, Mürsel; Bircan, Hasan; Dapo, Haris; Boztosun, Ismail

2018-03-01

The photonuclear reactions, first extensively studied in the 1970's and performed using the gamma rays obtained via bremsstrahlung, are a standard nuclear physics experiment. In this study, a non-enriched Rubidium sample was irradiated with photons produced by a clinical linear electron accelerator (cLINACs) with energies up to 18 MeV with the aim of activating it through photonuclear reactions. The activated sample was measured with a high purity germanium detector (HPGe) with the aim of measuring the transition energies and half-lives. The spectroscopic analysis performed on the obtained data yielded high quality results for the transition energies with precision matching or surpassing the literature data. For the half-lives the results were consistent with the literature, most notably the half-life of 84mRb decay was determined as 20.28(2) m. The results for both energies and half-lives further show that the clinical linear accelerators can be successfully used as an efficient tool in experimental nuclear research endeavors.

High Power Microwaves for Defense and Accelerator Applications

DTIC Science & Technology

1990-06-11

pulsed power machines are typically made for laboratory simulation of charged particle and radiation spectra of nuclear explosions . Early on, it was...cathode and then explosive 10 ionization. After the first few nanoseconds, the electron emission is from a plasma produced at the cathode. Typically the...Virtually nothing is needed except an electron beam source. This power and simplicity makes vircators particularly interesting for single shot or explosively

Compact quasi-monoenergetic photon sources from laser-plasma accelerators for nuclear detection and characterization

NASA Astrophysics Data System (ADS)

Geddes, Cameron G. R.; Rykovanov, Sergey; Matlis, Nicholas H.; Steinke, Sven; Vay, Jean-Luc; Esarey, Eric H.; Ludewigt, Bernhard; Nakamura, Kei; Quiter, Brian J.; Schroeder, Carl B.; Toth, Csaba; Leemans, Wim P.

2015-05-01

Near-monoenergetic photon sources at MeV energies offer improved sensitivity at greatly reduced dose for active interrogation, and new capabilities in treaty verification, nondestructive assay of spent nuclear fuel and emergency response. Thomson (also referred to as Compton) scattering sources are an established method to produce appropriate photon beams. Applications are however restricted by the size of the required high-energy electron linac, scattering (photon production) system, and shielding for disposal of the high energy electron beam. Laser-plasma accelerators (LPAs) produce GeV electron beams in centimeters, using the plasma wave driven by the radiation pressure of an intense laser. Recent LPA experiments are presented which have greatly improved beam quality and efficiency, rendering them appropriate for compact high-quality photon sources based on Thomson scattering. Designs for MeV photon sources utilizing the unique properties of LPAs are presented. It is shown that control of the scattering laser, including plasma guiding, can increase photon production efficiency. This reduces scattering laser size and/or electron beam current requirements to scale compatible with the LPA. Lastly, the plasma structure can decelerate the electron beam after photon production, reducing the size of shielding required for beam disposal. Together, these techniques provide a path to a compact photon source system.

Abnormal nuclear envelopes in the striatum and motor deficits in DYT11 myoclonus-dystonia mouse models

PubMed Central

Yokoi, Fumiaki; Dang, Mai T.; Zhou, Tong; Li, Yuqing

2012-01-01

DYT11 myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonic symptoms and caused by mutations in paternally expressed SGCE, which codes for ɛ-sarcoglycan. Paternally inherited Sgce heterozygous knock-out (KO) mice exhibit motor deficits and spontaneous myoclonus. Abnormal nuclear envelopes have been reported in cellular and mouse models of early-onset DYT1 generalized torsion dystonia; however, the relationship between the abnormal nuclear envelopes and motor symptoms are not clear. Furthermore, it is not known whether abnormal nuclear envelope exists in non-DYT1 dystonia. In the present study, abnormal nuclear envelopes in the striatal medium spiny neurons (MSNs) were found in Sgce KO mice. To analyze whether the loss of ɛ-sarcoglycan in the striatum alone causes abnormal nuclear envelopes, motor deficits or myoclonus, we produced paternally inherited striatum-specific Sgce conditional KO (Sgce sKO) mice and analyzed their phenotypes. Sgce sKO mice exhibited motor deficits in both beam-walking and accelerated rotarod tests, while they did not exhibit abnormal nuclear envelopes, alteration in locomotion, or myoclonus. The results suggest that the loss of ɛ-sarcoglycan in the striatum contributes to motor deficits, while it alone does not produce abnormal nuclear envelopes or myoclonus. Development of therapies targeting the striatum to compensate for the loss of ɛ-sarcoglycan function may rescue the motor deficits in DYT11 M-D patients. PMID:22080833

Production of isotopes using high power proton beams

DOEpatents

Nolen, Jr., Jerry A.; Gomes, Itacil C.

2015-12-01

The invention provides for a method for producing isotopes using a beam of particles from an accelerator, whereby the beam is maintained at between about 70 to 2000 MeV; and contacting a thorium-containing target with the particles. The medically important isotope .sup.225Ac is produced via the nuclear reaction (p,2p6n), whereby an energetic proton causes the ejection of 2 protons and 6 neutrons from a .sup.232Th target nucleus. Another medically important isotope .sup.213Bi is then available as a decay product. The production of highly purified .sup.211At is also provided.

Fifty years of accelerator based physics at Chalk River

DOE Office of Scientific and Technical Information (OSTI.GOV)

McKay, John W.

1999-04-26

The Chalk River Laboratories of Atomic Energy of Canada Ltd. was a major centre for Accelerator based physics for the last fifty years. As early as 1946, nuclear structure studies were started on Cockroft-Walton accelerators. A series of accelerators followed, including the world's first Tandem, and the MP Tandem, Superconducting Cyclotron (TASCC) facility that was opened in 1986. The nuclear physics program was shut down in 1996. This paper will describe some of the highlights of the accelerators and the research of the laboratory.

The measurement programme at the neutron time-of-flight facility n_TOF at CERN

NASA Astrophysics Data System (ADS)

Gunsing, F.; Aberle, O.; Andrzejewski, J.; Audouin, L.; Bécares, V.; Bacak, M.; Balibrea-Correa, J.; Barbagallo, M.; Barros, S.; Bečvář, F.; Beinrucker, C.; Belloni, F.; Berthoumieux, E.; Billowes, J.; Bosnar, D.; Brown, A.; Brugger, M.; Caamaño, M.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Cardella, R.; Casanovas, A.; Castelluccio, D. M.; Cerutti, F.; Chen, Y. H.; Chiaveri, E.; Colonna, N.; Cortés-Giraldo, M. A.; Cortés, G.; Cosentino, L.; Damone, L. A.; Deo, K.; Diakaki, M.; Domingo-Pardo, C.; Dressler, R.; Dupont, E.; Durán, I.; Fernández-Domínguez, B.; Ferrari, A.; Ferreira, P.; Finocchiaro, P.; Frost, R. J. W.; Furman, V.; Ganesan, S.; García, A. R.; Gawlik, A.; Gheorghe, I.; Gilardoni, S.; Glodariu, T.; Gonçalves, I. F.; González, E.; Goverdovski, A.; Griesmayer, E.; Guerrero, C.; Göbel, K.; Harada, H.; Heftrich, T.; Heinitz, S.; Hernández-Prieto, A.; Heyse, J.; Jenkins, D. G.; Jericha, E.; Käppeler, F.; Kadi, Y.; Kalamara, A.; Katabuchi, T.; Kavrigin, P.; Ketlerov, V.; Khryachkov, V.; Kimura, A.; Kivel, N.; Kokkoris, M.; Krtička, M.; Kurtulgil, D.; Leal-Cidoncha, E.; Lederer, C.; Leeb, H.; Lerendegui, J.; Licata, M.; Meo, S. Lo; Lonsdale, S. J.; Losito, R.; Macina, D.; Marganiec, J.; Martínez, T.; Masi, A.; Massimi, C.; Mastinu, P.; Mastromarco, M.; Matteucci, F.; Maugeri, E. A.; Mazzone, A.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Montesano, S.; Musumarra, A.; Nolte, R.; Negret, A.; Oprea, A.; Palomo-Pinto, F. R.; Paradela, C.; Patronis, N.; Pavlik, A.; Perkowski, J.; Porras, I.; Praena, J.; Quesada, J. M.; Radeck, D.; Rajeev, K.; Rauscher, T.; Reifarth, R.; Riego-Perez, A.; Robles, M.; Rout, P.; Rubbia, C.; Ryan, J. A.; Sabaté-Gilarte, M.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Sedyshev, P.; Smith, A. G.; Sosnin, N. V.; Stamatopoulos, A.; Suryanarayana, S. V.; Tagliente, G.; Tain, J. L.; Tarifeño-Saldivia, A.; Tarrío, D.; Tassan-Got, L.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Vlachoudis, V.; Vlastou, R.; Wallner, A.; Warren, S.; Weigand, M.; Weiss, C.; Wolf, C.; Woods, P. J.; Wright, T.; Žugec, P.

2017-09-01

Neutron-induced reaction cross sections are important for a wide variety of research fields ranging from the study of nuclear level densities, nucleosynthesis to applications of nuclear technology like design, and criticality and safety assessment of existing and future nuclear reactors, radiation dosimetry, medical applications, nuclear waste transmutation, accelerator-driven systems and fuel cycle investigations. Simulations and calculations of nuclear technology applications largely rely on evaluated nuclear data libraries. The evaluations in these libraries are based both on experimental data and theoretical models. CERN's neutron time-of-flight facility n_TOF has produced a considerable amount of experimental data since it has become fully operational with the start of its scientific measurement programme in 2001. While for a long period a single measurement station (EAR1) located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2) in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at n_TOF will be presented.

Accelerator–Reactor Coupling for Energy Production in Advanced Nuclear Fuel Cycles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heidet, Florent; Brown, Nicholas R.; Haj Tahar, Malek

2015-01-01

This article is a review of several accelerator-reactor interface issues and nuclear fuel cycle applications of accelerator-driven subcritical systems. The systems considered here have the primary goal of energy production, but that goal is accomplished via a specific application in various proposed nuclear fuel cycles, such as breed-and-burn of fertile material or burning of transuranic material. Several basic principles are reviewed, starting from the proton beam window including the target, blanket, reactor core, and up to the fuel cycle. We focused on issues of interest, e.g. the impact of the energy required to run the accelerator and associated systems onmore » the potential electricity delivered to the grid. Accelerator-driven systems feature many of the constraints and issues associated with critical reactors, with the added challenges of subcritical operation and coupling to an accelerator. Reliable accelerator operation and avoidance of beam trips are a critically important. One interesting challenge is measurement of blanket subcriticality level during operation. We also reviewed the potential benefits of accelerator-driven systems in various nuclear fuel cycle applications. Ultimately, accelerator-driven subcritical systems with the goal of transmutation of transuranic material have lower 100,000-year radioactivity versus a critical fast reactor with recycle of uranium and plutonium.« less

The National Superconducting Cyclotron Laboratory

NASA Astrophysics Data System (ADS)

Gelbke, C. Korad; Morrissey, D. J.; York, R. C.

1996-10-01

The National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University has constructed and operates two superconducting cyclotrons for research in nuclear science, accelerator and instrumental physics. The K500, the world's first superconducting cyclotron, was commissioned in 1982 and the K1200, the world's most powerful cyclotron, was commissioned in 1988. Heavy-ion beams across the entire periodic table produced in a pair of ECR ion sources and accelerated to energies on the order of 100 MeV/A are delivered to a modern and versatile complement of experimental apparatus, including the new S800 high-resolution superconducting magnetic spectrograph now undergoing initial testing. The diverse variety of beams are used for studies of the quantum-statistical properties of hot nuclei, the liquid-gas phase transition in nuclear matter, and for nuclear structure research, particularly with radioactive ion beams from the A1200 fragment separator. The NSCL provides radioactive nuclear beams out to the limits of stability on both the neutron-rich and the proton-rich sides of the valley of stability. The laboratory is also used for multi-disciplinary research in astrophysics, condensed matter physics, geophysics, medicine, and biology. The NSCL has recently proposed a major upgrade of its facility based on coupled operation of the two cyclotrons. The upgrade will provide large increases in beam intensities for radioactive beam production and increased energies of the heaviest beams.

Neutron dosimetry at a high-energy electron-positron collider

NASA Astrophysics Data System (ADS)

Bedogni, Roberto

Electron-positron colliders with energy of hundreds of MeV per beam have been employed for studies in the domain of nuclear and sub-nuclear physics. The typical structure of such a collider includes an LINAC, able to produce both types of particles, an accumulator ring and a main ring, whose diameter ranges from several tens to hundred meters and allows circulating particle currents of several amperes per beam. As a consequence of the interaction of the primary particles with targets, shutters, structures and barriers, a complex radiation environment is produced. This paper addresses the neutron dosimetry issues associated with the operation of such accelerators, referring in particular to the DAΦ NE complex, operative since 1997 at INFN-Frascati National Laboratory (Italy). Special attention is given to the active and passive techniques used for the spectrometric and dosimetric characterization of the workplace neutron fields, for radiation protection dosimetry purposes.

Livermore Accelerator Source for Radionuclide Science (LASRS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Scott; Bleuel, Darren; Johnson, Micah

The Livermore Accelerator Source for Radionuclide Science (LASRS) will generate intense photon and neutron beams to address important gaps in the study of radionuclide science that directly impact Stockpile Stewardship, Nuclear Forensics, and Nuclear Material Detection. The co-location of MeV-scale neutral and photon sources with radiochemical analytics provides a unique facility to meet current and future challenges in nuclear security and nuclear science.

The MIT HEDP Accelerator Facility for education and advanced diagnostics development for OMEGA, Z and the NIF

NASA Astrophysics Data System (ADS)

Petrasso, R.; Gatu Johnson, M.; Armstrong, E.; Han, H. W.; Kabadi, N.; Lahmann, B.; Orozco, D.; Rojas Herrera, J.; Sio, H.; Sutcliffe, G.; Frenje, J.; Li, C. K.; Séguin, F. H.; Leeper, R.; Ruiz, C. L.; Sangster, T. C.

2015-11-01

The MIT HEDP Accelerator Facility utilizes a 135-keV linear electrostatic ion accelerator, a D-T neutron source and two x-ray sources for development and characterization of nuclear diagnostics for OMEGA, Z, and the NIF. The ion accelerator generates D-D and D-3He fusion products through acceleration of D ions onto a 3He-doped Erbium-Deuteride target. Fusion reaction rates around 106 s-1 are routinely achieved, and fluence and energy of the fusion products have been accurately characterized. The D-T neutron source generates up to 6 × 108 neutrons/s. The two x-ray generators produce spectra with peak energies of 35 keV and 225 keV and maximum dose rates of 0.5 Gy/min and 12 Gy/min, respectively. Diagnostics developed and calibrated at this facility include CR-39 based charged-particle spectrometers, neutron detectors, and the particle Time-Of-Flight (pTOF) and Magnetic PTOF CVD-diamond-based bang time detectors. The accelerator is also a vital tool in the education of graduate and undergraduate students at MIT. This work was supported in part by SNL, DOE, LLE and LLNL.

Rare isotope accelerator project in Korea and its application to high energy density sciences

NASA Astrophysics Data System (ADS)

Chung, M.; Chung, Y. S.; Kim, S. K.; Lee, B. J.; Hoffmann, D. H. H.

2014-01-01

As a national science project, the Korean government has recently established the Institute for Basic Science (IBS) with the goal of conducting world-class research in basic sciences. One of the core facilities for the IBS will be the rare isotope accelerator which can produce high-intensity rare isotope beams to investigate the fundamental properties of nature, and also to support a broad research program in material sciences, medical and biosciences, and future nuclear energy technologies. The construction of the accelerator is scheduled to be completed by approximately 2017. The design of the accelerator complex is optimized to deliver high average beam current on targets, and to maximize the production of rare isotope beams through the simultaneous use of Isotope Separation On-Line (ISOL) and In-Flight Fragmentation (IFF) methods. The proposed accelerator is, however, not optimal for high energy density science, which usually requires very high peak currents on the target. In this study, we present possible beam-plasma experiments that can be done within the scope of the current accelerator design, and we also investigate possible future extension paths that may enable high energy density science with intense pulsed heavy ion beams.

The Los Alamos Neutron Science Center Spallation Neutron Sources

NASA Astrophysics Data System (ADS)

Nowicki, Suzanne F.; Wender, Stephen A.; Mocko, Michael

The Los Alamos Neutron Science Center (LANSCE) provides the scientific community with intense sources of neutrons, which can be used to perform experiments supporting civilian and national security research. These measurements include nuclear physics experiments for the defense program, basic science, and the radiation effect programs. This paper focuses on the radiation effects program, which involves mostly accelerated testing of semiconductor parts. When cosmic rays strike the earth's atmosphere, they cause nuclear reactions with elements in the air and produce a wide range of energetic particles. Because neutrons are uncharged, they can reach aircraft altitudes and sea level. These neutrons are thought to be the most important threat to semiconductor devices and integrated circuits. The best way to determine the failure rate due to these neutrons is to measure the failure rate in a neutron source that has the same spectrum as those produced by cosmic rays. Los Alamos has a high-energy and a low-energy neutron source for semiconductor testing. Both are driven by the 800-MeV proton beam from the LANSCE accelerator. The high-energy neutron source at the Weapons Neutron Research (WNR) facility uses a bare target that is designed to produce fast neutrons with energies from 100 keV to almost 800 MeV. The measured neutron energy distribution from WNR is very similar to that of the cosmic-ray-induced neutrons in the atmosphere. However, the flux provided at the WNR facility is typically 5×107 times more intense than the flux of the cosmic-ray-induced neutrons. This intense neutron flux allows testing at greatly accelerated rates. An irradiation test of less than an hour is equivalent to many years of neutron exposure due to cosmic-ray neutrons. The low-energy neutron source is located at the Lujan Neutron Scattering Center. It is based on a moderated source that provides useful neutrons from subthermal energies to ∼100 keV. The characteristics of these sources, and ongoing industry program are described in this paper.

Accelerating Innovation: How Nuclear Physics Benefits Us All

DOE R&D Accomplishments Database

2011-01-01

Innovation has been accelerated by nuclear physics in the areas of improving our health; making the world safer; electricity, environment, archaeology; better computers; contributions to industry; and training the next generation of innovators.

PIXE-PIGE analysis of teeth from children with and without cystic fibrosis

NASA Astrophysics Data System (ADS)

Cua, Florence T.

1990-04-01

Proton-induced X-ray emission (PIXE) and proton-induced gamma emission (PIGE) were used to analyze Ca, Sr, Fe, Zn, Cu and F, Na, P, Mg respectively in teeth of children with and without cystic fibrosis. The accelerators used were the 3 MeV proton Van de Graaff accelerator at the Brookhaven National Laboratory, NY, USA for the first run and the 8 MV FN-tandem Van de Graaff accelerator at the Nuclear Physics Laboratory, Rutgers University, NJ, USA producing a 4 MeV proton beam for the second and third run. Description of the experimental setup, and the data acquisition system are described in the text. A summary of the results on element concentration as a function of types of teeth and correlation studies are in the text and in F.T. Cua, Ph.D. Thesis, Rutgers Univ. (1989).

Hermes III

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasti, D.E.; Ramirez, J.J.; Prestwich, K.R.

1985-01-01

Hermes III is a major new gamma-ray simulator that is part of the Simulation Technology Laboratory Project. This accelerator will significantly improve the capability of Sandia National Laboratories and the Department of Energy to evaluate the effects of gamma-ray radiation from nuclear weapons on weapons subsystems. This accelerator will be designed to produce 10/sup 5/R, 5 x 10/sup 12/ R/S and 2 x 10/sup 20/ R/S/sup 2/ over a 500 cm/sup 2/ area. The radiation dose will vary less than a factor of two over this area and less than a factor of four throughout a volume found by extendingmore » this surface 15 cm further from the gamma-ray converter. The minimum dose in this volume will be greater than or equal to5 x 10/sup 4/ R. The accelerator will be designed with sufficient reliability and short enough turn-around time to produce more than 600 radiation pulses per year. In Hermes III we are increasing the peak power in the beam from 1.2 TW of Hermes II to 16 TW. Two techniques for achieving these high powers have been successfully developed. The first technique is a high current linear induction accelerator with several parallel beams. Experiments to evaluate this concept were done on the MABE accelerator. The second concept uses induction cavities and a magnetically insulated transmission line (MITL) to form a multi-terawatt voltage adder. This report gives a detailed description of Hermes III and its components.« less

The South African isotope facility project

NASA Astrophysics Data System (ADS)

Bark, R. A.; Barnard, A. H.; Conradie, J. L.; de Villiers, J. G.; van Schalkwyk, P. A.

2018-05-01

The South African Isotope Facility (SAIF) is a project in which iThemba LABS plans to build a radioactive-ion beam (RIB) facility. The project is divided into the Accelerator Centre of Exotic Isotopes (ACE Isotopes) and the Accelerator Centre for Exotic Beams (ACE Beams). For ACE Isotopes, a high-current, 70 MeV cyclotron will be acquired to take radionuclide production off the existing Separated Sector Cyclotron (SSC). A freed up SSC will then be available for an increased tempo of nuclear physics research and to serve as a driver accelerator for the ACE Beams project, in which protons will be used for the direct fission of Uranium, producing beams of fission fragments. The ACE Beams project has begun with "LeRIB" - a Low Energy RIB facility, now under construction. In a collaboration with INFN Legnaro, the target/ion-source "front-end" will be a copy of the front-end developed for the SPES project. A variety of targets may be inserted into the SPES front-end; a uranium-carbide target has been designed to produce up to 2 × 1013 fission/s using a 70 MeV proton beam of 150 µA intensity.

Neutron-induced fission cross section of 242Pu from 15 MeV to 20 MeV

NASA Astrophysics Data System (ADS)

Jovančević, N.; Salvador-Castineira, P.; Daraban, L.; Vidali, M.; Heyse, J.; Oberstedt, S.; Hambsch, F.-J.; Bonaldi, C.; Geerts, W.

2017-09-01

Accurate nuclear-data needs in the fast-neutron-energy region have been recently addressed for the development of next generation nuclear power plants (GEN-IV) by the OECD Nuclear Energy Agency (NEA). This sensitivity study has shown that of particular interest is the 242Pu(n,f) cross section for fast reactor systems. Measurements have been performed with quasi-monoenergetic neutrons in the energy range from 15 MeV to 20 MeV produced by the Van de Graaff accelerator of the JRC-Geel. A twin Frisch-grid ionization chamber has been used in a back-to-back configuration as fission fragment detector. The 242Pu(n,f) cross section has been normalized to 238U(n,f) cross section data. The results were compared with existing literature data and show acceptable agreement within 5%.

Low Cost Nuclear Thermal Rocket Cermet Fuel Element Environment Testing

NASA Technical Reports Server (NTRS)

Bradley, D. E.; Mireles, O. R.; Hickman, R. R.

2011-01-01

Deep space missions with large payloads require high specific impulse and relatively high thrust to achieve mission goals in reasonable time frames.1,2 Conventional storable propellants produce average specific impulse. Nuclear thermal rockets capable of producing high specific impulse are proposed. Nuclear thermal rockets employ heat produced by fission reaction to heat and therefore accelerate hydrogen, which is then forced through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000 K), and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high-temperature hydrogen exposure on fuel elements are limited.3 The primary concern is the mechanical failure of fuel elements that employ high-melting-point metals, ceramics, or a combination (cermet) as a structural matrix into which the nuclear fuel is distributed. The purpose of the testing is to obtain data to assess the properties of the non-nuclear support materials, as-fabricated, and determine their ability to survive and maintain thermal performance in a prototypical NTR reactor environment of exposure to hydrogen at very high temperatures. The fission process of the planned fissile material and the resulting heating performance is well known and does not therefore require that active fissile material be integrated in this testing. A small-scale test bed designed to heat fuel element samples via non-contact radio frequency heating and expose samples to hydrogen is being developed to assist in optimal material and manufacturing process selection without employing fissile material. This paper details the test bed design and results of testing conducted to date.

Accelerator Reactor Coupling for Energy Production in Advanced Nuclear Fuel Cycles

DOE PAGES

Brown, Nicholas R.; Heidet, Florent; Haj Tahar, Malek

2016-01-01

This article is a review of several accelerator–reactor interface issues and nuclear fuel cycle applications of acceleratordriven subcritical systems. The systems considered here have the primary goal of energy production, but that goal is accomplished via a specific application in various proposed nuclear fuel cycles, such as breed-and-burn of fertile material or burning of transuranic material. Several basic principles are reviewed, starting from the proton beam window including the target, blanket, reactor core, and up to the fuel cycle. We focus on issues of interest, such as the impact of the energy required to run the accelerator and associated systemsmore » on the potential electricity delivered to the grid. Accelerator-driven systems feature many of the constraints and issues associated with critical reactors, with the added challenges of subcritical operation and coupling to an accelerator. Reliable accelerator operation and avoidance of beam trips are critically important. One interesting challenge is measurement of blanket subcriticality level during operation. We also review the potential benefits of accelerator-driven systems in various nuclear fuel cycle applications. Ultimately, accelerator-driven subcritical systems with the goal of transmutation of transuranic material have lower 100,000-year radioactivity than a critical fast reactor with recycling of uranium and plutonium.« less

Fission-Fusion: A new reaction mechanism for nuclear astrophysics based on laser-ion acceleration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thirolf, P. G.; Gross, M.; Allinger, K.

We propose to produce neutron-rich nuclei in the range of the astrophysical r-process around the waiting point N = 126 by fissioning a dense laser-accelerated thorium ion bunch in a thorium target (covered by a CH{sub 2} layer), where the light fission fragments of the beam fuse with the light fission fragments of the target. Via the 'hole-boring' mode of laser Radiation Pressure Acceleration using a high-intensity, short pulse laser, very efficiently bunches of {sup 232}Th with solid-state density can be generated from a Th target and a deuterated CD{sub 2} foil, both forming the production target assembly. Laser-accelerated Thmore » ions with about 7 MeV/u will pass through a thin CH{sub 2} layer placed in front of a thicker second Th foil (both forming the reaction target) closely behind the production target and disintegrate into light and heavy fission fragments. In addition, light ions (d,C) from the CD{sub 2} layer of the production target will be accelerated as well, inducing the fission process of {sup 232}Th also in the second Th layer. The laser-accelerated ion bunches with solid-state density, which are about 10{sup 14} times more dense than classically accelerated ion bunches, allow for a high probability that generated fission products can fuse again. The high ion beam density may lead to a strong collective modification of the stopping power, leading to significant range and thus yield enhancement. Using a high-intensity laser as envisaged for the ELI-Nuclear Physics project in Bucharest (ELI-NP), order-of-magnitude estimates promise a fusion yield of about 10{sup 3} ions per laser pulse in the mass range of A = 180-190, thus enabling to approach the r-process waiting point at N = 126.« less

Accelerated radiation damage test facility using a 5 MV tandem ion accelerator

NASA Astrophysics Data System (ADS)

Wady, P. T.; Draude, A.; Shubeita, S. M.; Smith, A. D.; Mason, N.; Pimblott, S. M.; Jimenez-Melero, E.

2016-01-01

We have developed a new irradiation facility that allows to perform accelerated damage tests of nuclear reactor materials at temperatures up to 400 °C using the intense proton (<100 μA) and heavy ion (≈10 μA) beams produced by a 5 MV tandem ion accelerator. The dedicated beam line for radiation damage studies comprises: (1) beam diagnosis and focusing optical components, (2) a scanning and slit system that allows uniform irradiation of a sample area of 0.5-6 cm2, and (3) a sample stage designed to be able to monitor in-situ the sample temperature, current deposited on the sample, and the gamma spectrum of potential radio-active nuclides produced during the sample irradiation. The beam line capabilities have been tested by irradiating a 20Cr-25Ni-Nb stabilised stainless steel with a 3 MeV proton beam to a dose level of 3 dpa. The irradiation temperature was 356 °C, with a maximum range in temperature values of ±6 °C within the first 24 h of continuous irradiation. The sample stage is connected to ground through an electrometer to measure accurately the charge deposited on the sample. The charge can be integrated in hardware during irradiation, and this methodology removes uncertainties due to fluctuations in beam current. The measured gamma spectrum allowed the identification of the main radioactive nuclides produced during the proton bombardment from the lifetimes and gamma emissions. This dedicated radiation damage beam line is hosted by the Dalton Cumbrian Facility of the University of Manchester.

Scalability of the LEU-Modified Cintichem Process: 3-MeV Van de Graaff and 35-MeV Electron Linear Accelerator Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rotsch, David A.; Brossard, Tom; Roussin, Ethan

Molybdenum-99, the mother of Tc-99m, can be produced from fission of U-235 in nuclear reactors and purified from fission products by the Cintichem process, later modified for low-enriched uranium (LEU) targets. The key step in this process is the precipitation of Mo with α-benzoin oxime (ABO). The stability of this complex to radiation has been examined. Molybdenum-ABO was irradiated with 3 MeV electrons produced by a Van de Graaff generator and 35 MeV electrons produced by a 50 MeV/25 kW electron linear accelerator. Dose equivalents of 1.7–31.2 kCi of Mo-99 were administered to freshly prepared Mo-ABO. Irradiated samples of Mo-ABOmore » were processed according to the LEU Modified-Cintichem process. The Van de Graaff data indicated good radiation stability of the Mo-ABO complex up to ~15 kCi dose equivalents of Mo-99 and nearly complete destruction at doses >24 kCi Mo-99. The linear accelerator data indicate that even at 6.2 kCi of Mo-99 equivalence of dose, the sample lost ~20% of Mo-99. The 20% loss of Mo-99 at this low dose may be attributed to thermal decomposition of the product from the heat deposited in the sample during irradiation.« less

Development of a negative ion-based neutral beam injector in Novosibirsk.

PubMed

Ivanov, A A; Abdrashitov, G F; Anashin, V V; Belchenko, Yu I; Burdakov, A V; Davydenko, V I; Deichuli, P P; Dimov, G I; Dranichnikov, A N; Kapitonov, V A; Kolmogorov, V V; Kondakov, A A; Sanin, A L; Shikhovtsev, I V; Stupishin, N V; Sorokin, A V; Popov, S S; Tiunov, M A; Belov, V P; Gorbovsky, A I; Kobets, V V; Binderbauer, M; Putvinski, S; Smirnov, A; Sevier, L

2014-02-01

A 1000 keV, 5 MW, 1000 s neutral beam injector based on negative ions is being developed in the Budker Institute of Nuclear Physics, Novosibirsk in collaboration with Tri Alpha Energy, Inc. The innovative design of the injector features the spatially separated ion source and an electrostatic accelerator. Plasma or photon neutralizer and energy recuperation of the remaining ion species is employed in the injector to provide an overall energy efficiency of the system as high as 80%. A test stand for the beam acceleration is now under construction. A prototype of the negative ion beam source has been fabricated and installed at the test stand. The prototype ion source is designed to produce 120 keV, 1.5 A beam.

Future Facility: FAIR at GSI

NASA Astrophysics Data System (ADS)

Rosner, Guenther

2007-05-01

The Facility for Antiproton and Ion Research, FAIR, is a new particle accelerator facility to be built at the GSI site in Germany. The research at FAIR will cover a wide range of topics in nuclear and hadron physics, high density plasma and atomic physics, and applications in condensed matter physics and biology. A 1.1 km circumference double ring of rapidly cycling 100 and 300 Tm synchrotrons, will be FAIR's central accelerator system. It will be used to produce, inter alia, high intensity secondary beams of antiprotons and short-lived radioactive nuclei. A subsequent suite of cooler and storage rings will deliver heavy ion and antiproton beams of unprecedented quality. Large experiments are presently being designed by the NUSTAR, PANDA, PAX, CBM, SPARC, FLAIR, HEDgeHOB and BIOMAT collaborations.

A UHV compatible source for a highly polarized thermal atomic beam of radioactive 8Li

NASA Astrophysics Data System (ADS)

Jänsch, H. J.; Kirchner, G.; Kühlert, O.; Lisowski, M.; Paggel, J. J.; Platzer, R.; Schillinger, R.; Tilsner, H.; Weindel, C.; Winnefeld, H.; Fick, D.

2000-12-01

A beam of the radioactive isotope 8Li is prepared at thermal velocities. The nuclei are highly spin polarized by transverse optical pumping of the thermal beam. The installation is ultra-high vacuum (UHV) compatible in a non-UHV accelerator environment. Since the atomic beam is used in a surface science experiment, where contamination must be avoided, special emphasis is given to the vacuum coupling of the accelerator/ 8Li production/surface experimental areas. The atomic beam is produced by stopping the nuclear reaction products and evaporating them again from high-temperature graphite. To enhance the atomic beam, a novel tubular thermalizer is applied. The thermal polarized atomic beam intensity is approximately 5×10 8 atoms/s sr.

Targets and methods for target preparation for radionuclide production

DOEpatents

Zhuikov, Boris L; Konyakhin, Nicolai A; Kokhanyuk, Vladimir M; Srivastava, Suresh C

2012-10-16

The invention relates to nuclear technology, and to irradiation targets and their preparation. One embodiment of the present invention includes a method for preparation of a target containing intermetallic composition of antimony Ti--Sb, Al--Sb, Cu--Sb, or Ni--Sb in order to produce radionuclides (e.g., tin-117 m) with a beam of accelerated particles. The intermetallic compounds of antimony can be welded by means of diffusion welding to a copper backing cooled during irradiation on the beam of accelerated particles. Another target can be encapsulated into a shell made of metallic niobium, stainless steel, nickel or titanium cooled outside by water during irradiation. Titanium shell can be plated outside by nickel to avoid interaction with the cooling water.

Production of 64Cu and 67Cu radiopharmaceuticals using zinc target irradiated with accelerator neutrons

NASA Astrophysics Data System (ADS)

Kawabata, Masako; Hashimoto, Kazuyuki; Saeki, Hideya; Sato, Nozomi; Motoishi, Shoji; Nagai, Yasuki

2014-09-01

Copper radioisotopes have gained a lot of attention in radiopharmaceuticals owing to their unique decay characteristics. The longest half-life β emitter, 67Cu, is thought to be suitable for targeted radio-immunotherapy. Adequate production of 67Cu to meet the demands of clinical studies has not been fully established. Another attractive copper isotope, 64Cu has possible applications as a diagnostic imaging tracer combined with a therapeutic effect. This work proposes a production method using accelerator neutrons in which two copper radioisotopes can be produced: 1) 68Zn(n,x)67Cu and 2) 64Zn(n,p)64Cu using ~14 MeV neutrons generated by natC(d, n) reaction, both from natural or enriched zinc oxides. The generated 64,67Cu were separated from the target zinc oxide using a chelating and an anion exchange columns and were labelled with two widely studied chelators where the labelling efficiency was found to be acceptably good. The major advantage of this method is that a significant amount of 64,67Cu with a very few impurity radionuclides are produced which also makes the separation procedure simple. Provided an accelerator supplying an Ed = ~ 40 MeV, a wide application of 64,67Cu based drugs in nuclear medicine is feasible in the near future. We will present the characteristics of this production method using accelerator neutrons including the chemical separation processes.

High Intensity Proton Accelerator Project in Japan (J-PARC).

PubMed

Tanaka, Shun-ichi

2005-01-01

The High Intensity Proton Accelerator Project, named as J-PARC, was started on 1 April 2001 at Tokai-site of JAERI. The accelerator complex of J-PARC consists of three accelerators: 400 MeV Linac, 3 GeV rapid cycle synchrotron and 50 GeV synchrotron; and four major experimental facilities: Material and Life Science Facility, Nuclear and Particle Physics Facility, Nuclear Transmutation Experiment Facility and Neutrino Facility. The outline of the J-PARC is presented with the current status of construction.

An accelerator-based Boron Neutron Capture Therapy (BNCT) facility based on the 7Li(p,n)7Be

NASA Astrophysics Data System (ADS)

Musacchio González, Elizabeth; Martín Hernández, Guido

2017-09-01

BNCT (Boron Neutron Capture Therapy) is a therapeutic modality used to irradiate tumors cells previously loaded with the stable isotope 10B, with thermal or epithermal neutrons. This technique is capable of delivering a high dose to the tumor cells while the healthy surrounding tissue receive a much lower dose depending on the 10B biodistribution. In this study, therapeutic gain and tumor dose per target power, as parameters to evaluate the treatment quality, were calculated. The common neutron-producing reaction 7Li(p,n)7Be for accelerator-based BNCT, having a reaction threshold of 1880.4 keV, was considered as the primary source of neutrons. Energies near the reaction threshold for deep-seated brain tumors were employed. These calculations were performed with the Monte Carlo N-Particle (MCNP) code. A simple but effective beam shaping assembly (BSA) was calculated producing a high therapeutic gain compared to previously proposed facilities with the same nuclear reaction.

Characterizing Neutron Diagnostics on the nTOF Line at SUNY Geneseo

NASA Astrophysics Data System (ADS)

Harrison, Hannah; Seppala, Hannah; Visca, Hannah; Wakwella, Praveen; Fletcher, Kurt; Padalino, Stephen; Forrest, Chad; Regan, Sean; Sangster, Craig

2016-10-01

Charged particle beams from SUNY Geneseo's 1.7 MV Tandem Pelletron Accelerator induce nuclear reactions that emit neutrons ranging from 0.5 to 17.9 MeV via 2H(d,n)3He and 11B(d,n)12C. This adjustable neutron source can be used to calibrate ICF and HEDP neutron scintillators for ICF diagnostics. However, gamma rays and muons, which are often present during an accelerator-based calibration, are difficult to differentiate from neutron signals in scintillators. To mitigate this problem, a new neutron time-of-flight (nTOF) line has been constructed. The nTOF timing is measured using the associated particle technique. A charged particle produced by the nuclear reaction serves as a start signal, while its associated neutron is the stop signal. Each reaction is analyzed event-by-event to determine whether the scintillator signal was generated by a neutron, gamma or muon. Using this nTOF technique, the neutron response for different scintillation detectors can be determined. Funded in part by a LLE contract through the DOE.

Study of the 28Si(d,α)26Al Nuclear Reaction at Low Energies

NASA Astrophysics Data System (ADS)

Araujo-Escalona, Victoria; Acosta, L.; Andrade, E.; Barrón-Palos, L.; de Lucio, O.; Favela, F.; Huerta, A.; Lopez, E.; Rita, P. Santa; Solis, C.; Chávez, E.

26Al is known as a γ-ray emitter in the universe. Since its half-life is only 0.72 My it's the obvious evidence of ongoing nucleosynthesis. This isotope is also known as an origin of an abundance-anomaly of 26Mg observed in meteorites. There is also 26Al production on Earth due to the continuous cosmic ray bombardment. Therefore, a precise knowledge of the production rates for 26Al are needed. In this paper, we present a progress report on our measurements of the 28Si(d,α)26Al nuclear reaction. The experimental protocol consists of three steps: i) target preparation, ii) deuteron irradiations and iii) 26Al off line counting using Accelerator Mass Spectrometry (AMS). Due to accelerator failure, deuteron irradiations had to be interrupted and the number or 26Al produced was insufficient to extract cross sections as expected. In step (ii), given our special geometry requirements we ended up facing the old problem of a goat tethered inside a circular field, which we turned into a tool to fine-tune the beam-target alignment in the micron range.

Nuclear Structure Studies with Stable and Radioactive Beams: The SPES radioactive ion beam project

NASA Astrophysics Data System (ADS)

de Angelis, G.; SPES Collaboration; Prete, G.; Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Rossignoli, M.; Monetti, A.; Lollo, M.; Calderolla, M.; Vasquez, J.; Zafiropoulos, D.; Sarchiapone, L.; Benini, D.; Favaron, P.; Rigato, M.; Pegoraro, R.; Maniero, D.; Calabretta, L.; Comunian, M.; Maggiore, M.; Lombardi, A.; Piazza, L.; Porcellato, A. M.; Roncolato, C.; Bisoffi, G.; Pisent, A.; Galatà, A.; Giacchini, M.; Bassato, G.; Canella, S.; Gramegna, F.; Valiente, J.; Bermudez, J.; Mastinu, P. F.; Esposito, J.; Wyss, J.; Russo, A.; Zanella, S.

2015-04-01

A new Radioactive Ion Beam (RIB) facility (SPES) is presently under construction at the Legnaro National Laboratories of INFN. The SPES facility is based on the ISOL method using 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 fission on an Uranium target 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 facility is to deliver high intensity radioactive ion beams of neutron rich nuclei for nuclear physics research as well as to be an interdisciplinary research centre for radio-isotopes production for medicine and for neutron beams.

Signature energetic analysis of accelerate electron beam after first acceleration station by accelerating stand of Joint Institute for Nuclear Research

NASA Astrophysics Data System (ADS)

Sledneva, A. S.; Kobets, V. V.

2017-06-01

The linear electron accelerator based on the LINAC - 800 accelerator imported from the Netherland is created at Joint Institute for Nuclear Research in the framework of the project on creation of the Testbed with an electron beam of a linear accelerator with an energy up to 250 MV. Currently two accelerator stations with a 60 MV energy of a beam are put in operation and the work is to put the beam through accelerating section of the third accelerator station. The electron beam with an energy of 23 MeV is used for testing the crystals (BaF2, CsI (native), and LYSO) in order to explore the opportunity to use them in particle detectors in experiments: Muon g-2, Mu2e, Comet, whose preparation requires a detailed study of the detectors properties such as their irradiation by the accelerator beams.

Pyroelectric Crystal Accelerator In The Department Of Physics And Nuclear Engineering At West Point

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gillich, Don; Kovanen, Andrew; Anderson, Tom

The Nuclear Science and Engineering Research Center (NSERC), a Defense Threat Reduction Agency (DTRA) office located at the United States Military Academy (USMA), sponsors and manages cadet and faculty research in support of DTRA objectives. The NSERC has created an experimental pyroelectric crystal accelerator program to enhance undergraduate education at USMA in the Department of Physics and Nuclear Engineering. This program provides cadets with hands-on experience in designing their own experiments using an inexpensive tabletop accelerator. This device uses pyroelectric crystals to ionize and accelerate gas ions to energies of {approx}100 keV. Within the next year, cadets and faculty atmore » USMA will use this device to create neutrons through the deuterium-deuterium (D-D) fusion process, effectively creating a compact, portable neutron generator. The double crystal pyroelectric accelerator will also be used by students to investigate neutron, x-ray, and ion spectroscopy.« less

Heavy Ion Acceleration at J-PARC

NASA Astrophysics Data System (ADS)

SATO, Susumu

2018-02-01

J-PARC, the Japan Proton Accelerator Research Complex, is an accelerator, which provides a high-intensity proton beam. Recently as a very attractive project, the acceleration of heavy ions produced by supplementary ion sources, called J-PARC-HI, is seriously contemplated by domestic as well as international communities. The planned facility would accelerate heavy ions up to U92+ with a beam energy 20 AGeV ( of 6.2 AGeV). The highlight of the J-PARC-HI project is its very high beam rate up to 1011 Hz, which will enable the study of very rare events. Taking advantage of this high intensity, J-PARC-HI will carry out frontier studies of new and rare observables in this energy region: (i) nuclear medium modification of chiral property of vector mesons through low-mass di-lepton signal, (ii) QCD critical pointcharacterization through event-by-event fluctuation signals of particle production, (iii) systematic measurements related to the equation of state through collective flow signal or two-particle momentum correlation signal, or (iv) the search of hyper nuclei with multi strangeness including or exceeding S = 3. The current plan of J-PARC-HI aims to carrying out the first experimental measurements in 2025.

Direct Laser Acceleration in Laser Wakefield Accelerators

NASA Astrophysics Data System (ADS)

Shaw, J. L.; Froula, D. H.; Marsh, K. A.; Joshi, C.; Lemos, N.

2017-10-01

The direct laser acceleration (DLA) of electrons in a laser wakefield accelerator (LWFA) has been investigated. We show that when there is a significant overlap between the drive laser and the trapped electrons in a LWFA cavity, the accelerating electrons can gain energy from the DLA mechanism in addition to LWFA. The properties of the electron beams produced in a LWFA, where the electrons are injected by ionization injection, have been investigated using particle-in-cell (PIC) code simulations. Particle tracking was used to demonstrate the presence of DLA in LWFA. Further PIC simulations comparing LWFA with and without DLA show that the presence of DLA can lead to electron beams that have maximum energies that exceed the estimates given by the theory for the ideal blowout regime. The magnitude of the contribution of DLA to the energy gained by the electron was found to be on the order of the LWFA contribution. The presence of DLA in a LWFA can also lead to enhanced betatron oscillation amplitudes and increased divergence in the direction of the laser polarization. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

Incineration of nuclear waste by accelerator

NASA Astrophysics Data System (ADS)

Martino, J.; Fioni, G.; Leray, S.

1998-10-01

An important international effort is devoted to find a suitable solution to incinerate radioactive nuclear waste issued from conventional power plants and from nuclear disarmament. Practically all innovative projects consist of a sub critical system driven by an external neutron source obtained by spallation induced by a high intensity proton accelerator irradiating a heavy target. New nuclear data measurements are necessary for the realization of these systems, in particular a good knowledge of the spallation process and of the neutron cross sections for transuranic elements are essential.

Compact ion source neutron generator

DOEpatents

Schenkel, Thomas; Persaud, Arun; Kapadia, Rehan; Javey, Ali; Chang-Hasnain, Constance; Rangelow, Ivo; Kwan, Joe

2015-10-13

A neutron generator includes a conductive substrate comprising a plurality of conductive nanostructures with free-standing tips and a source of an atomic species to introduce the atomic species in proximity to the free-standing tips. A target placed apart from the substrate is voltage biased relative to the substrate to ionize and accelerate the ionized atomic species toward the target. The target includes an element capable of a nuclear fusion reaction with the ionized atomic species to produce a one or more neutrons as a reaction by-product.

Recent Results from ISOLDE and HIE-ISOLDE

NASA Astrophysics Data System (ADS)

Borge, María J. G.

2018-02-01

ISOLDE is the CERN facility dedicated to the production of rare ion beams for many different experiments in the fields of nuclear and atomic physics, materials science and life sciences. The HIE-ISOLDE, Higher Intensity and Energy upgrade has finished its stage 1 dedicated to upgrade the energy up to 5.5 MeV/u, producing the first radioactive beams with this energy in September 9th 2016. Recent results from the low energy and post-accelerated beams are given in this contribution.

Is There an Interest to Use Deuteron Beams to Produce Non-Conventional Radionuclides?

PubMed Central

Alliot, Cyrille; Audouin, Nadia; Barbet, Jacques; Bonraisin, Anne-Cecile; Bossé, Valérie; Bourdeau, Cécile; Bourgeois, Mickael; Duchemin, Charlotte; Guertin, Arnaud; Haddad, Ferid; Huclier-Markai, Sandrine; Kerdjoudj, Rabah; Laizé, Johan; Métivier, Vincent; Michel, Nathalie; Mokili, Marcel; Pageau, Mickael; Vidal, Aurélien

2015-01-01

With the recent interest on the theranostic approach, there has been a renewed interest for alternative radionuclides in nuclear medicine. They can be produced using common production routes, i.e., using protons accelerated by biomedical cyclotrons or neutrons produced in research reactors. However, in some cases, it can be more valuable to use deuterons as projectiles. In the case of Cu-64, smaller quantities of the expensive target material, Ni-64, are used with deuterons as compared with protons for the same produced activity. For the Sc-44m/Sc-44g generator, deuterons afford a higher Sc-44m production yield than with protons. Finally, in the case of Re-186g, deuterons lead to a production yield five times higher than protons. These three examples show that it is of interest to consider not only protons or neutrons but also deuterons to produce alternative radionuclides. PMID:26029696

Electron Accelerator Shielding Design of KIPT Neutron Source Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhong, Zhaopeng; Gohar, Yousry

The Argonne National Laboratory of the United States and the Kharkov Institute of Physics and Technology of the Ukraine have been collaborating on the design, development and construction of a neutron source facility at Kharkov Institute of Physics and Technology utilizing an electron-accelerator-driven subcritical assembly. The electron beam power is 100 kW using 100-MeV electrons. The facility was designed to perform basic and applied nuclear research, produce medical isotopes, and train nuclear specialists. The biological shield of the accelerator building was designed to reduce the biological dose to less than 5.0e-03 mSv/h during operation. The main source of the biologicalmore » dose for the accelerator building is the photons and neutrons generated from different interactions of leaked electrons from the electron gun and the accelerator sections with the surrounding components and materials. The Monte Carlo N-particle extended code (MCNPX) was used for the shielding calculations because of its capability to perform electron-, photon-, and neutron-coupled transport simulations. The photon dose was tallied using the MCNPX calculation, starting with the leaked electrons. However, it is difficult to accurately tally the neutron dose directly from the leaked electrons. The neutron yield per electron from the interactions with the surrounding components is very small, similar to 0.01 neutron for 100-MeV electron and even smaller for lower-energy electrons. This causes difficulties for the Monte Carlo analyses and consumes tremendous computation resources for tallying the neutron dose outside the shield boundary with an acceptable accuracy. To avoid these difficulties, the SOURCE and TALLYX user subroutines of MCNPX were utilized for this study. The generated neutrons were banked, together with all related parameters, for a subsequent MCNPX calculation to obtain the neutron dose. The weight windows variance reduction technique was also utilized for both neutron and photon dose calculations. Two shielding materials, heavy concrete and ordinary concrete, were considered for the shield design. The main goal is to maintain the total dose outside the shield boundary less than 5.0e-03 mSv/h during operation. The shield configuration and parameters of the accelerator building were determined and are presented in this paper. Copyright (C) 2016, Published by Elsevier Korea LLC on behalf of Korean Nuclear Society.« less

Progress towards an intense beam of positrons created by a Van de Graaff accelerator

NASA Astrophysics Data System (ADS)

Lund, K. R.; Weber, M. H.; Lynn, K. G.; Jennings, J.; Minnal, C.; Narimannezhad, A.; Rao, R.; Monster, K. A. W.

2017-12-01

A 4MV Van de Graaff accelerator was used to induce the nuclear reaction 12C(d,n)13N in order to produce an intense beam of positrons. The graphite target was heated so the radioactive 13N would desorb from the bulk into the vacuum. This radioactive gas is frozen onto a cryogenic freezer where it decays to produce an antiparticle beam of positrons. This high current beam is then guided into a superconducting magnet with field strength up to 7 Tesla where the positrons will be stored in a newly designed Micro-Penning-Malmberg trap. Several source geometries have been experimented on and found a maximum antimatter beam with a positron flux of greater than 0.55 ± 0.03 × 106 e+s-1 was achieved. This beam was produced using a solid rare gas moderator composed of krypton (Kr) at a temperature of 25 ± 5 K. Due to geometric restrictions on this set up and other loss mechanisms, 107-108 e+s-1 of the total number of positrons are lost. Simulations and preliminary experiments suggest a new geometry, currently under testing, will produce a beam of 107 e+s-1 or more. The setup and preliminary results for the new geometry will be discussed as well.

Progress in Characterizing Thermal Degradation of Ethylene-Propylene Rubber

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fifield, Leonard S.; Huang, Qian; Childers, Matthew I.

Ethylene-propylene rubber (EPR) is one of the two most common nuclear cable insulation materials. A large fraction of EPR-insulated cables in use in the nuclear industry were manufactured by The Okonite Company. Okoguard® is the name of the medium voltage thermoset EPR manufactured by The Okonite Company. Okoguard® has been produced with silane-treated clay filler and the characteristic pink color since the 1970’s. EPR is complex material that undergoes simultaneous reactions during thermal aging including oxidative and thermal cleavage and oxidative and thermal crosslinking. This reaction complexity makes precise EPR service life prediction from accelerated aging using approaches designed formore » single discreet reactions such as the Arrhenius approach problematic. Performance data and activation energies for EPR aged at conditions closer to service conditions will improve EPR lifetime prediction. In this report pink Okoguard® EPR insulation material has been thermally aged at elevated temperatures. A variety of characterization techniques have been employed to track material changes with aging. It was noted that EPR aged significant departure in aging behavior seemed to occur at accelerated aging temperatures between 140°C and 150°C at around 20 days of exposure. This may be due to alternative degradation mechanisms being accessed at this higher temperature and reinforces the need to perform accelerated aging for Okoguard® EPR service life prediction at temperatures below 150°C.« less

High-flux neutron source based on a liquid-lithium target

NASA Astrophysics Data System (ADS)

Halfon, S.; Feinberg, G.; Paul, M.; Arenshtam, A.; Berkovits, D.; Kijel, D.; Nagler, A.; Eliyahu, I.; Silverman, I.

2013-04-01

A prototype compact Liquid Lithium Target (LiLiT), able to constitute an accelerator-based intense neutron source, was built. The neutron source is intended for nuclear astrophysical research, boron neutron capture therapy (BNCT) in hospitals and material studies for fusion reactors. The LiLiT setup is presently being commissioned at Soreq Nuclear research Center (SNRC). The lithium target will produce neutrons through the 7Li(p,n)7Be reaction and it will overcome the major problem of removing the thermal power generated by a high-intensity proton beam, necessary for intense neutron flux for the above applications. The liquid-lithium loop of LiLiT is designed to generate a stable lithium jet at high velocity on a concave supporting wall with free surface toward the incident proton beam (up to 10 kW). During off-line tests, liquid lithium was flown through the loop and generated a stable jet at velocity higher than 5 m/s on the concave supporting wall. The target is now under extensive test program using a high-power electron-gun. Up to 2 kW electron beam was applied on the lithium flow at velocity of 4 m/s without any flow instabilities or excessive evaporation. High-intensity proton beam irradiation will take place at SARAF (Soreq Applied Research Accelerator Facility) superconducting linear accelerator currently in commissioning at SNRC.

High-flux neutron source based on a liquid-lithium target

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halfon, S.; Feinberg, G.; Paul, M.

2013-04-19

A prototype compact Liquid Lithium Target (LiLiT), able to constitute an accelerator-based intense neutron source, was built. The neutron source is intended for nuclear astrophysical research, boron neutron capture therapy (BNCT) in hospitals and material studies for fusion reactors. The LiLiT setup is presently being commissioned at Soreq Nuclear research Center (SNRC). The lithium target will produce neutrons through the {sup 7}Li(p,n){sup 7}Be reaction and it will overcome the major problem of removing the thermal power generated by a high-intensity proton beam, necessary for intense neutron flux for the above applications. The liquid-lithium loop of LiLiT is designed to generatemore » a stable lithium jet at high velocity on a concave supporting wall with free surface toward the incident proton beam (up to 10 kW). During off-line tests, liquid lithium was flown through the loop and generated a stable jet at velocity higher than 5 m/s on the concave supporting wall. The target is now under extensive test program using a high-power electron-gun. Up to 2 kW electron beam was applied on the lithium flow at velocity of 4 m/s without any flow instabilities or excessive evaporation. High-intensity proton beam irradiation will take place at SARAF (Soreq Applied Research Accelerator Facility) superconducting linear accelerator currently in commissioning at SNRC.« less

Status and Prospects of Hirfl Experiments on Nuclear Physics

NASA Astrophysics Data System (ADS)

Xu, H. S.; Zheng, C.; Xiao, G. Q.; Zhan, W. L.; Zhou, X. H.; Zhang, Y. H.; Sun, Z. Y.; Wang, J. S.; Gan, Z. G.; Huang, W. X.; Ma, X. W.

HIRFL is an accelerator complex consisting of 3 accelerators, 2 radioactive beams lines, 1 storage rings and a number of experimental setups. The research activities at HIRFL cover the fields of radio-biology, material science, atomic physics, and nuclear physics. This report mainly concentrates on the experiments of nuclear physics with the existing and planned experimental setups such as SHANS, RIBLL1, ETF, CSRe, PISA and HPLUS at HIRFL.

Radiography with cosmic-ray and compact accelerator muons; Exploring inner-structure of large-scale objects and landforms

PubMed Central

NAGAMINE, Kanetada

2016-01-01

Cosmic-ray muons (CRM) arriving from the sky on the surface of the earth are now known to be used as radiography purposes to explore the inner-structure of large-scale objects and landforms, ranging in thickness from meter to kilometers scale, such as volcanic mountains, blast furnaces, nuclear reactors etc. At the same time, by using muons produced by compact accelerators (CAM), advanced radiography can be realized for objects with a thickness in the sub-millimeter to meter range, with additional exploration capability such as element identification and bio-chemical analysis. In the present report, principles, methods and specific research examples of CRM transmission radiography are summarized after which, principles, methods and perspective views of the future CAM radiography are described. PMID:27725469

Radiography with cosmic-ray and compact accelerator muons; Exploring inner-structure of large-scale objects and landforms.

PubMed

Nagamine, Kanetada

2016-01-01

Cosmic-ray muons (CRM) arriving from the sky on the surface of the earth are now known to be used as radiography purposes to explore the inner-structure of large-scale objects and landforms, ranging in thickness from meter to kilometers scale, such as volcanic mountains, blast furnaces, nuclear reactors etc. At the same time, by using muons produced by compact accelerators (CAM), advanced radiography can be realized for objects with a thickness in the sub-millimeter to meter range, with additional exploration capability such as element identification and bio-chemical analysis. In the present report, principles, methods and specific research examples of CRM transmission radiography are summarized after which, principles, methods and perspective views of the future CAM radiography are described.

Isotope shifts from collinear laser spectroscopy of doubly charged yttrium isotopes

NASA Astrophysics Data System (ADS)

Vormawah, L. J.; Vilén, M.; Beerwerth, R.; Campbell, P.; Cheal, B.; Dicker, A.; Eronen, T.; Fritzsche, S.; Geldhof, S.; Jokinen, A.; Kelly, S.; Moore, I. D.; Reponen, M.; Rinta-Antila, S.; Stock, S. O.; Voss, A.

2018-04-01

Collinear laser spectroscopy has been performed on doubly charged ions of radioactive yttrium in order to study the isotope shifts of the 294.6-nm 5 s 1/2 2S →5 p 1/2 2P line. The potential of such an alkali-metal-like transition to improve the reliability of atomic-field-shift and mass-shift factor calculations, and hence the extraction of nuclear mean-square radii, is discussed. Production of yttrium ion beams for such studies is available at the IGISOL IV Accelerator Laboratory, Jyväskylä, Finland. This newly recommissioned facility is described here in relation to the on-line study of accelerator-produced short-lived isotopes using collinear laser spectroscopy and application of the technique to doubly charged ions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Youinou, Gilles Jean-Michel

Neutron cross-sections characterize the way neutrons interact with matter. They are essential to most nuclear engineering projects and, even though theoretical progress has been made as far as the predictability of neutron cross-section models, measurements are still indispensable to meet tight design requirements for reduced uncertainties. Within the field of fission reactor technology, one can identify the following specializations that rely on the availability of accurate neutron cross-sections: (1) fission reactor design, (2) nuclear fuel cycles, (3) nuclear safety, (4) nuclear safeguards, (5) reactor monitoring and neutron fluence determination and (6) waste disposal and transmutation. In particular, the assessment ofmore » advanced fuel cycles requires an extensive knowledge of transuranics cross sections. Plutonium isotopes, but also americium, curium and up to californium isotope data are required with a small uncertainty in order to optimize significant features of the fuel cycle that have an impact on feasibility studies (e.g. neutron doses at fuel fabrication, decay heat in a repository, etc.). Different techniques are available to determine neutron cross sections experimentally, with the common denominator that a source of neutrons is necessary. It can either come from an accelerator that produces neutrons as a result of interactions between charged particles and a target, or it can come from a nuclear reactor. When the measurements are performed with an accelerator, they are referred to as differential since the analysis of the data provides the cross-sections for different discrete energies, i.e. σ(E i), and for the diffusion cross sections for different discrete angles. Another approach is to irradiate a very pure sample in a test reactor such as the Advanced Test Reactor (ATR) at INL and, after a given time, determine the amount of the different transmutation products. The precise characterization of the nuclide densities before and after neutron irradiation allows to infer energy-integrated neutron cross sections, i.e. ∫₀ ∞σ(E)φ(E)dE, where φ(E) is the neutron flux “seen” by the sample. This approach, which is usually defined and led by reactor physicists, is referred to as integral and is the object of this report. These two sources of information, i.e. differential and integral, are complementary and are used by the nuclear physicists in charge of producing the evaluated nuclear data files used by the nuclear community (ENDF, JEFF…). The generation of accurate nuclear data files requires an iterative process involving reactor physicists and nuclear data evaluators. This experimental program has been funded by the ATR National Scientific User Facility (ATR-NSUF) and by the DOE Office of Science in the framework of the Recovery Act. It has been given the name MANTRA for Measurement of Actinides Neutron TRAnsmutation.« less

Characterizing ICF Neutron Diagnostics on the nTOF line at SUNY Geneseo

NASA Astrophysics Data System (ADS)

Simone, Angela; Padalino, Stephen; Turner, Ethan; Ginnane, Mary Kate; Dubois, Natalie; Fletcher, Kurtis; Giordano, Michael; Lawson-Keister, Patrick; Harrison, Hannah; Visca, Hannah; Sangster, Craig; Regan, Sean

2014-10-01

Charged particle beams from the Geneseo 1.7 MV tandem Pelletron accelerator produce nuclear reactions that emit neutrons in the range of 0.5 to 17.9 MeV via the d(d,n)3He and 11B(d,n)12C reactions. The neutron energy and flux can be adjusted by controlling the accelerator beam current and potential. This adjustable neutron source makes it possible to calibrate ICF and HEDP neutron scintillator diagnostics. However, gamma rays which are often present during an accelerator-based calibration are difficult to differentiate from neutron signals in scintillators. To identify neutrons from gamma rays and to determine their energy, a permanent neutron time-of-flight (nTOF) line is being constructed. By detecting the scintillator signal in coincidence with an associated charged particle (ACP) produced in the reaction, the identity of the neutron can be known and its energy determined by time of flight. Using a 100% efficient surface barrier detector to count the ACPs, the absolute efficiency of the scintillator as a function of neutron energy can be determined. This is done by determining the ratio of the ACP counts in the singles spectrum to coincidence counts for matched solid angles of the SBD and scintillator. Funded in part by a LLE contract through the DOE.

A 13C(d,n)-based epithermal neutron source for Boron Neutron Capture Therapy.

PubMed

Capoulat, M E; Kreiner, A J

2017-01-01

Boron Neutron Capture Therapy (BNCT) requires neutron sources suitable for in-hospital siting. Low-energy particle accelerators working in conjunction with a neutron producing reaction are the most appropriate choice for this purpose. One of the possible nuclear reactions is 13 C(d,n) 14 N. The aim of this work is to evaluate the therapeutic capabilities of the neutron beam produced by this reaction, through a 30mA beam of deuterons of 1.45MeV. A Beam Shaping Assembly design was computationally optimized. Depth dose profiles in a Snyder head phantom were simulated with the MCNP code for a number of BSA configurations. In order to optimize the treatment capabilities, the BSA configuration was determined as the one that allows maximizing both the tumor dose and the penetration depth while keeping doses to healthy tissues under the tolerance limits. Significant doses to tumor tissues were achieved up to ∼6cm in depth. Peak doses up to 57Gy-Eq can be delivered in a fractionated scheme of 2 irradiations of approximately 1h each. In a single 1h irradiation, lower but still acceptable doses to tumor are also feasible. Treatment capabilities obtained here are comparable to those achieved with other accelerator-based neutron sources, making of the 13 C(d,n) 14 N reaction a realistic option for producing therapeutic neutron beams through a low-energy particle accelerator. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Materials modification using ions with energies below 1 MeV/u

NASA Astrophysics Data System (ADS)

Karlušić, M.; Jakšić, M.; Buljan, M.; Sancho-Parramon, J.; Bogdanović-Radović, I.; Radić, N.; Bernstorff, S.

2013-12-01

Materials modifications using swift heavy ion beams provided by large scale accelerators have been used for many years in a wide variety of ways, e.g. to produce ion tracks or to modify the shape of nanoparticles. In all those applications the most relevant parameter for the materials modification is the electronic stopping power and not the ion kinetic energy. For many materials, ions with energies below 1 MeV/u delivered from medium and small size accelerators have already sufficiently high electronic stopping power to modify materials in different ways. Also, in this energy range the nuclear stopping power can be large enough to provide additional opportunities for materials modifications. In the present paper, we review recent experimental activities of the Zagreb group where ion beams with energies below 1 MeV/u, obtained from a 6 MV EN Tandem Van de Graaff accelerator have been used. Additionally, we present several novel examples of materials modifications and their analysis with such ion beams.

CASPAR - Nuclear Astrophysics Underground

NASA Astrophysics Data System (ADS)

Senarath, Chamaka; Caspar Collaboration

2017-09-01

The CASPAR mainly focuses on Stellar Nucleosynthesis, its impact on the production of heavy elements and study the strength of stellar neutron sources that propels the s-process, 13C(α,n)16O and 22Ne(α,n)25Mg. Currently, implementation of a 1MV fully refurbished Van de Graaff accelerator that can provide a high intensity Î+/- beam, is being done at the Sanford Underground Research Facility (SURF). The accelerator is built among a collaboration of South Dakota School of Mines and Technology, University of Notre Dame and Colorado School of Mines. It is understood that cosmic ray neutron background radiation hampers experimental Nucleosynthesis studies, hence the need to go underground in search for a neutron free environment, to study these reactions at low energies is evident. The first beam was produced in the middle of summer 2017. The entire accelerator will be run before the end of this year. A detailed overview of goals of CASPAR will be presented. NFS Grant-1615197.

Magnetically insulated diode for generating pulsed neutron and gamma ray emissions

DOEpatents

Kuswa, G.W.; Leeper, R.J.

1984-08-16

A magnetically insulated diode employs a permanent magnet to generate a magnetic insulating field between a spaced anode and cathode in a vacuum. An ion source is provided in the vicinity of the anode and used to liberate ions for acceleration toward the cathode. The ions are virtually unaffected by the magnetic field and are accelerated into a target for generating a nuclear reaction. The ions and target material may be selected to generate either neutrons or gamma ray emissions from the reaction of the accelerated ions and the target. In another aspect of the invention, a field coil is employed as part of one of the electrodes. A plasma prefill is provided between the electrodes prior to the application of a pulsating potential to one of the electrodes. The field coil multiplies the applied voltage for high diode voltage applications. The diode may be used to generate a /sup 7/Li(p,..gamma..)/sup 8/Be reaction to produce 16.5 MeV gamma emission.

Monte Carlo simulations and measurements for efficiency determination of lead shielded plastic scintillator detectors

NASA Astrophysics Data System (ADS)

Yasin, Zafar; Negoita, Florin; Tabbassum, Sana; Borcea, Ruxandra; Kisyov, Stanimir

2017-12-01

The plastic scintillators are used in different areas of science and technology. One of the use of these scintillator detectors is as beam loss monitors (BLM) for new generation of high intensity heavy ion in superconducting linear accelerators. Operated in pulse counting mode with rather high thresholds and shielded by few centimeters of lead in order to cope with radiofrequency noise and X-ray background emitted by accelerator cavities, they preserve high efficiency for high energy gamma ray and neutrons produced in the nuclear reactions of lost beam particles with accelerator components. Efficiency calculation and calibration of detectors is very important before their practical usage. In the present work, the efficiency of plastic scintillator detectors is simulated using FLUKA for different gamma and neutron sources like, 60Co, 137Cs and 238Pu-Be. The sources are placed at different positions around the detector. Calculated values are compared with the measured values and a reasonable agreement is observed.

Magnetically insulated diode for generating pulsed neutron and gamma ray emissions

DOEpatents

Kuswa, Glenn W.; Leeper, Ramon J.

1987-01-01

A magnetically insulated diode employs a permanent magnet to generate a magnetic insulating field between a spaced anode and cathode in a vacuum. An ion source is provided in the vicinity of the anode and used to liberate ions for acceleration toward the cathode. The ions are virtually unaffected by the magnetic field and are accelerated into a target for generating an nuclear reaction. The ions and target material may be selected to generate either neutrons or gamma ray emissions from the reaction of the accelerated ions and the target. In another aspect of the invention, a field coil is employed as part of one of the electrodes. A plasma prefill is provided between the electrodes prior to the application of a pulsating potential to one of the electrodes. The field coil multiplies the applied voltage for high diode voltage applications. The diode may be used to generate a .sup.7 Li(p,.gamma.).sup.8 Be reaction to produce 16.5 MeV gamma emission.

Development of an inertial confinement fusion platform to study charged-particle-producing nuclear reactions relevant to nuclear astrophysics

DOE PAGES

Gatu Johnson, M.; Zylstra, A. B.; Bacher, A.; ...

2017-03-28

Here, this paper describes the development of a platform to study astrophysically relevant nuclear reactions using inertial-confinement fusion implosions on the OMEGA and National Ignition Facility laser facilities, with a particular focus on optimizing the implosions to study charged-particle- producing reactions. Primary requirements on the platform are high yield, for high statistics in the fusion product measurements, combined with low areal density, to allow the charged fusion products to escape. This is optimally achieved with direct-drive exploding pusher implosions using thin-glass-shell capsules. Mitigation strategies to eliminate a possible target sheath potential which would accelerate the emitted ions are discussed. Themore » potential impact of kinetic effects on the implosions is also considered. The platform is initially employed to study the complementary T(t,2n)α, T( 3He,np)α and 3He( 3He,2p)α reactions. Proof-of-principle results from the first experiments demonstrating the ability to accurately measure the energy and yields of charged particles are presented. Lessons learned from these experiments will be used in studies of other reactions. Ultimately, the goals are to explore thermonuclear reaction rates and fundamental nuclear physics in stellarlike plasma environments, and to push this new frontier of nuclear astrophysics into unique regimes not reachable through existing platforms, with thermal ion velocity distributions, plasma screening, and low reactant energies.« less

Development of Nuclear Renewable Oil Shale Systems for Flexible Electricity and Reduced Fossil Fuel Emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daniel Curtis; Charles Forsberg; Humberto Garcia

2015-05-01

We propose the development of Nuclear Renewable Oil Shale Systems (NROSS) in northern Europe, China, and the western United States to provide large supplies of flexible, dispatchable, very-low-carbon electricity and fossil fuel production with reduced CO2 emissions. NROSS are a class of large hybrid energy systems in which base-load nuclear reactors provide the primary energy used to produce shale oil from kerogen deposits and simultaneously provide flexible, dispatchable, very-low-carbon electricity to the grid. Kerogen is solid organic matter trapped in sedimentary shale, and large reserves of this resource, called oil shale, are found in northern Europe, China, and the westernmore » United States. NROSS couples electricity generation and transportation fuel production in a single operation, reduces lifecycle carbon emissions from the fuel produced, improves revenue for the nuclear plant, and enables a major shift toward a very-low-carbon electricity grid. NROSS will require a significant development effort in the United States, where kerogen resources have never been developed on a large scale. In Europe, however, nuclear plants have been used for process heat delivery (district heating), and kerogen use is familiar in certain countries. Europe, China, and the United States all have the opportunity to use large scale NROSS development to enable major growth in renewable generation and either substantially reduce or eliminate their dependence on foreign fossil fuel supplies, accelerating their transitions to cleaner, more efficient, and more reliable energy systems.« less

Development of an inertial confinement fusion platform to study charged-particle-producing nuclear reactions relevant to nuclear astrophysics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gatu Johnson, M.; Zylstra, A. B.; Bacher, A.

Here, this paper describes the development of a platform to study astrophysically relevant nuclear reactions using inertial-confinement fusion implosions on the OMEGA and National Ignition Facility laser facilities, with a particular focus on optimizing the implosions to study charged-particle- producing reactions. Primary requirements on the platform are high yield, for high statistics in the fusion product measurements, combined with low areal density, to allow the charged fusion products to escape. This is optimally achieved with direct-drive exploding pusher implosions using thin-glass-shell capsules. Mitigation strategies to eliminate a possible target sheath potential which would accelerate the emitted ions are discussed. Themore » potential impact of kinetic effects on the implosions is also considered. The platform is initially employed to study the complementary T(t,2n)α, T( 3He,np)α and 3He( 3He,2p)α reactions. Proof-of-principle results from the first experiments demonstrating the ability to accurately measure the energy and yields of charged particles are presented. Lessons learned from these experiments will be used in studies of other reactions. Ultimately, the goals are to explore thermonuclear reaction rates and fundamental nuclear physics in stellarlike plasma environments, and to push this new frontier of nuclear astrophysics into unique regimes not reachable through existing platforms, with thermal ion velocity distributions, plasma screening, and low reactant energies.« less

The physics design of accelerator-driven transmutation systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Venneri, F.

1995-10-01

Nuclear systems under study in the Los Alamos Accelerator-Driven Transmutation Technology program (ADTT) will allow the destruction of nuclear spent fuel and weapons-return plutonium, as well as the production of nuclear energy from the thorium cycle, without a long-lived radioactive waste stream. The subcritical systems proposed represent a radical departure from traditional nuclear concepts (reactors), yet the actual implementation of ADTT systems is based on modest extrapolations of existing technology. These systems strive to keep the best that the nuclear technology has developed over the years, within a sensible conservative design envelope and eventually manage to offer a safe, lessmore » expensive and more environmentally sound approach to nuclear power.« less

Technical developments at the NASA Space Radiation Laboratory.

PubMed

Lowenstein, D I; Rusek, A

2007-06-01

The NASA Space Radiation Laboratory (NSRL) located at Brookhaven National Laboratory (BNL) is a center for space radiation research in both the life and physical sciences. BNL is a multidisciplinary research facility operated for the Office of Science of the US Department of Energy (DOE). The BNL scientific research portfolio supports a large and diverse science and technology program including research in nuclear and high-energy physics, material science, chemistry, biology, medial science, and nuclear safeguards and security. NSRL, in operation since July 2003, is an accelerator-based facility which provides particle beams for radiobiology and physics studies (Lowenstein in Phys Med 17(supplement 1):26-29 2001). The program focus is to measure the risks and to ameliorate the effects of radiation encountered in space, both in low earth orbit and extended missions beyond the earth. The particle beams are produced by the Booster synchrotron, an accelerator that makes up part of the injector sequence of the DOE nuclear physics program's Relativistic Heavy Ion Collider. Ion species from protons to gold are presently available, at energies ranging from <100 to >1,000 MeV/n. The NSRL facility has recently brought into operation the ability to rapidly switch species and beam energy to supply a varied spectrum onto a given specimen. A summary of past operation performance, plans for future operations and recent and planned hardware upgrades will be described.

Development of advanced technological systems for accelerator transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Batskikh, G.I.; Bondarev, B.I.; Durkin, A.P.

1995-10-01

A development concept of the accelerator nuclear energy reactors is considered for energy generation and nuclear power plant waste conversion into short-lived nuclides along with the requirements imposed on the technological systems necessary for implementation of such projects. The state of art in the field is discussed.

Ultra-high vacuum photoelectron linear accelerator

DOEpatents

Yu, David U.L.; Luo, Yan

2013-07-16

An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.

Physics division annual report 2006.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glover, J.; Physics

2008-02-28

This report highlights the activities of the Physics Division of Argonne National Laboratory in 2006. The Division's programs include the operation as a national user facility of ATLAS, the Argonne Tandem Linear Accelerator System, research in nuclear structure and reactions, nuclear astrophysics, nuclear theory, investigations in medium-energy nuclear physics as well as research and development in accelerator technology. The mission of nuclear physics is to understand the origin, evolution and structure of baryonic matter in the universe--the core of matter, the fuel of stars, and the basic constituent of life itself. The Division's research focuses on innovative new ways tomore » address this mission.« less

The Los Alamos Neutron Science Center Spallation Neutron Sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nowicki, Suzanne F.; Wender, Stephen A.; Mocko, Michael

The Los Alamos Neutron Science Center (LANSCE) provides the scientific community with intense sources of neutrons, which can be used to perform experiments supporting civilian and national security research. These measurements include nuclear physics experiments for the defense program, basic science, and the radiation effect programs. This paper focuses on the radiation effects program, which involves mostly accelerated testing of semiconductor parts. When cosmic rays strike the earth's atmosphere, they cause nuclear reactions with elements in the air and produce a wide range of energetic particles. Because neutrons are uncharged, they can reach aircraft altitudes and sea level. These neutronsmore » are thought to be the most important threat to semiconductor devices and integrated circuits. The best way to determine the failure rate due to these neutrons is to measure the failure rate in a neutron source that has the same spectrum as those produced by cosmic rays. Los Alamos has a high-energy and a low-energy neutron source for semiconductor testing. Both are driven by the 800-MeV proton beam from the LANSCE accelerator. The high-energy neutron source at the Weapons Neutron Research (WNR) facility uses a bare target that is designed to produce fast neutrons with energies from 100 keV to almost 800 MeV. The measured neutron energy distribution from WNR is very similar to that of the cosmic-ray-induced neutrons in the atmosphere. However, the flux provided at the WNR facility is typically 5×107 times more intense than the flux of the cosmic-ray-induced neutrons. This intense neutron flux allows testing at greatly accelerated rates. An irradiation test of less than an hour is equivalent to many years of neutron exposure due to cosmic-ray neutrons. The low-energy neutron source is located at the Lujan Neutron Scattering Center. It is based on a moderated source that provides useful neutrons from subthermal energies to ~100 keV. The characteristics of these sources, and ongoing industry program are described in this paper.« less

The Los Alamos Neutron Science Center Spallation Neutron Sources

DOE PAGES

Nowicki, Suzanne F.; Wender, Stephen A.; Mocko, Michael

2017-10-26

The Los Alamos Neutron Science Center (LANSCE) provides the scientific community with intense sources of neutrons, which can be used to perform experiments supporting civilian and national security research. These measurements include nuclear physics experiments for the defense program, basic science, and the radiation effect programs. This paper focuses on the radiation effects program, which involves mostly accelerated testing of semiconductor parts. When cosmic rays strike the earth's atmosphere, they cause nuclear reactions with elements in the air and produce a wide range of energetic particles. Because neutrons are uncharged, they can reach aircraft altitudes and sea level. These neutronsmore » are thought to be the most important threat to semiconductor devices and integrated circuits. The best way to determine the failure rate due to these neutrons is to measure the failure rate in a neutron source that has the same spectrum as those produced by cosmic rays. Los Alamos has a high-energy and a low-energy neutron source for semiconductor testing. Both are driven by the 800-MeV proton beam from the LANSCE accelerator. The high-energy neutron source at the Weapons Neutron Research (WNR) facility uses a bare target that is designed to produce fast neutrons with energies from 100 keV to almost 800 MeV. The measured neutron energy distribution from WNR is very similar to that of the cosmic-ray-induced neutrons in the atmosphere. However, the flux provided at the WNR facility is typically 5×107 times more intense than the flux of the cosmic-ray-induced neutrons. This intense neutron flux allows testing at greatly accelerated rates. An irradiation test of less than an hour is equivalent to many years of neutron exposure due to cosmic-ray neutrons. The low-energy neutron source is located at the Lujan Neutron Scattering Center. It is based on a moderated source that provides useful neutrons from subthermal energies to ~100 keV. The characteristics of these sources, and ongoing industry program are described in this paper.« less

High Energy Density Plasmas (HEDP) for studies of basic nuclear science relevant to Stellar and Big Bang Nucleosynthesis

NASA Astrophysics Data System (ADS)

Frenje, Johan

2014-06-01

Thermonuclear reaction rates and nuclear processes have been explored traditionally by means of conventional accelerator experiments, which are difficult to execute at conditions relevant to stellar nucleosynthesis. Thus, nuclear reactions at stellar energies are often studied through extrapolations from higher-energy data or in low-background underground experiments. Even when measurements are possible using accelerators at relevant energies, thermonuclear reaction rates in stars are inherently different from those in accelerator experiments. The fusing nuclei are surrounded by bound electrons in accelerator experiments, whereas electrons occupy mainly continuum states in a stellar environment. Nuclear astrophysics research will therefore benefit from an enlarged toolkit for studies of nuclear reactions. In this presentation, we report on the first use of High Energy Density Plasmas for studies of nuclear reactions relevant to basic nuclear science, stellar and Big Bang nucleosynthesis. These experiments were carried out at the OMEGA laser facility at University of Rochester and the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, in which spherical capsules were irradiated with powerful lasers to compress and heat the fuel to high enough temperatures and densities for nuclear reactions to occur. Four experiments will be highlighted in this presentation. In the first experiment, the differential cross section for the elastic neutron-triton (n-T) scattering at 14.1 MeV was measured with significantly higher accuracy than achieved in accelerator experiments. In the second experiment, the T(t,2n)4He reaction, a mirror reaction to the 3He(3He,2p)4He reaction that plays an important role in the proton-proton chain that transforms hydrogen into ordinary 4He in stars like our Sun, was studied at energies in the range 15-40 keV. In the third experiment, the 3He+3He solar fusion reaction was studied directly, and in the fourth experiment, we probed the T+3He reaction, possibly relevant to Big Bang nucleosynthesis.

Nuclear data activities at the n_TOF facility at CERN

NASA Astrophysics Data System (ADS)

Gunsing, F.; Aberle, O.; Andrzejewski, J.; Audouin, L.; Bécares, V.; Bacak, M.; Balibrea-Correa, J.; Barbagallo, M.; Barros, S.; Bečvář, F.; Beinrucker, C.; Belloni, F.; Berthoumieux, E.; Billowes, J.; Bosnar, D.; Brugger, M.; Caamaño, M.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Cardella, R.; Casanovas, A.; Castelluccio, D. M.; Cerutti, F.; Chen, Y. H.; Chiaveri, E.; Colonna, N.; Cortés-Giraldo, M. A.; Cortés, G.; Cosentino, L.; Damone, L. A.; Deo, K.; Diakaki, M.; Domingo-Pardo, C.; Dressler, R.; Dupont, E.; Durán, I.; Fernández-Domínguez, B.; Ferrari, A.; Ferreira, P.; Finocchiaro, P.; Frost, R. J. W.; Furman, V.; Ganesan, S.; García, A. R.; Gawlik, A.; Gheorghe, I.; Glodariu, T.; Gonçalves, I. F.; González, E.; Goverdovski, A.; Griesmayer, E.; Guerrero, C.; Göbel, K.; Harada, H.; Heftrich, T.; Heinitz, S.; Hernández-Prieto, A.; Heyse, J.; Jenkins, D. G.; Jericha, E.; Käppeler, F.; Kadi, Y.; Katabuchi, T.; Kavrigin, P.; Ketlerov, V.; Khryachkov, V.; Kimura, A.; Kivel, N.; Kokkoris, M.; Krtička, M.; Leal-Cidoncha, E.; Lederer, C.; Leeb, H.; Lerendegui, J.; Licata, M.; Lo Meo, S.; Lonsdale, S. J.; Losito, R.; Macina, D.; Marganiec, J.; Martínez, T.; Masi, A.; Massimi, C.; Mastinu, P.; Mastromarco, M.; Matteucci, F.; Maugeri, E. A.; Mazzone, A.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Montesano, S.; Musumarra, A.; Nolte, R.; Oprea, A.; Palomo-Pinto, F. R.; Paradela, C.; Patronis, N.; Pavlik, A.; Perkowski, J.; Porras, I.; Praena, J.; Quesada, J. M.; Rajeev, K.; Rauscher, T.; Reifarth, R.; Riego-Perez, A.; Robles, M.; Rout, P.; Radeck, D.; Rubbia, C.; Ryan, J. A.; Sabaté-Gilarte, M.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Sedyshev, P.; Smith, A. G.; Stamatopoulos, A.; Suryanarayana, S. V.; Tagliente, G.; Tain, J. L.; Tarifeño-Saldivia, A.; Tarrío, D.; Tassan-Got, L.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Vlachoudis, V.; Vlastou, R.; Wallner, A.; Warren, S.; Weigand, M.; Weiss, C.; Wolf, C.; Woods, P. J.; Wright, T.; Žugec, P.

2016-10-01

Nuclear data in general, and neutron-induced reaction cross sections in particular, are important for a wide variety of research fields. They play a key role in the safety and criticality assessment of nuclear technology, not only for existing power reactors but also for radiation dosimetry, medical applications, the transmutation of nuclear waste, accelerator-driven systems, fuel cycle investigations and future reactor systems as in Generation IV. Applications of nuclear data are also related to research fields as the study of nuclear level densities and stellar nucleosynthesis. Simulations and calculations of nuclear technology applications largely rely on evaluated nuclear data libraries. The evaluations in these libraries are based both on experimental data and theoretical models. Experimental nuclear reaction data are compiled on a worldwide basis by the international network of Nuclear Reaction Data Centres (NRDC) in the EXFOR database. The EXFOR database forms an important link between nuclear data measurements and the evaluated data libraries. CERN's neutron time-of-flight facility n_TOF has produced a considerable amount of experimental data since it has become fully operational with the start of the scientific measurement programme in 2001. While for a long period a single measurement station (EAR1) located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2) in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at CERN's neutron time-of-flight facility n_TOF will be presented.

Solar He-3: Information from nuclear reactions in flares

NASA Technical Reports Server (NTRS)

Ramaty, R.; Kozlovsky, B.

1974-01-01

Information on solar He-3 from nuclear reactions in flares was considered. Consideration was also given to the development of models for these reactions as well as the abundance of He-3 in the photosphere. Data show that abundances may be explained by nuclear reactions of flare acceleration protons and alpha particles with the ambient atmosphere, provided that various assumptions are made on the directionality of the interacting beams and acceleration of the particles after production.

Laboratory Astrophysics Prize: Laboratory Astrophysics with Nuclei

NASA Astrophysics Data System (ADS)

Wiescher, Michael

2018-06-01

Nuclear astrophysics is concerned with nuclear reaction and decay processes from the Big Bang to the present star generation controlling the chemical evolution of our universe. Such nuclear reactions maintain stellar life, determine stellar evolution, and finally drive stellar explosion in the circle of stellar life. Laboratory nuclear astrophysics seeks to simulate and understand the underlying processes using a broad portfolio of nuclear instrumentation, from reactor to accelerator from stable to radioactive beams to map the broad spectrum of nucleosynthesis processes. This talk focuses on only two aspects of the broad field, the need of deep underground accelerator facilities in cosmic ray free environments in order to understand the nucleosynthesis in stars, and the need for high intensity radioactive beam facilities to recreate the conditions found in stellar explosions. Both concepts represent the two main frontiers of the field, which are being pursued in the US with the CASPAR accelerator at the Sanford Underground Research Facility in South Dakota and the FRIB facility at Michigan State University.

Teaching And Training Tools For The Undergraduate: Experience With A Rebuilt AN-400 Accelerator

NASA Astrophysics Data System (ADS)

Roberts, Andrew D.

2011-06-01

There is an increasingly recognized need for people trained in a broad range of applied nuclear science techniques, indicated by reports from the American Physical Society and elsewhere. Anecdotal evidence suggests that opportunities for hands-on training with small particle accelerators have diminished in the US, as development programs established in the 1960's and 1970's have been decommissioned over recent decades. Despite the reduced interest in the use of low energy accelerators in fundamental research, these machines can offer a powerful platform for bringing unique training opportunities to the undergraduate curriculum in nuclear physics, engineering and technology. We report here on the new MSU Applied Nuclear Science Lab, centered around the rebuild of an AN400 electrostatic accelerator. This machine is run entirely by undergraduate students under faculty supervision, allowing a great deal of freedom in its use without restrictions from graduate or external project demands.

Teaching And Training Tools For The Undergraduate: Experience With A Rebuilt AN-400 Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roberts, Andrew D.

2011-06-01

There is an increasingly recognized need for people trained in a broad range of applied nuclear science techniques, indicated by reports from the American Physical Society and elsewhere. Anecdotal evidence suggests that opportunities for hands-on training with small particle accelerators have diminished in the US, as development programs established in the 1960's and 1970's have been decommissioned over recent decades. Despite the reduced interest in the use of low energy accelerators in fundamental research, these machines can offer a powerful platform for bringing unique training opportunities to the undergraduate curriculum in nuclear physics, engineering and technology. We report here onmore » the new MSU Applied Nuclear Science Lab, centered around the rebuild of an AN400 electrostatic accelerator. This machine is run entirely by undergraduate students under faculty supervision, allowing a great deal of freedom in its use without restrictions from graduate or external project demands.« less

Thomas Jefferson National Accelerator Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grames, Joseph; Higinbotham, Douglas; Montgomery, Hugh

The Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia, USA, is one of ten national laboratories under the aegis of the Office of Science of the U.S. Department of Energy (DOE). It is managed and operated by Jefferson Science Associates, LLC. The primary facility at Jefferson Lab is the Continuous Electron Beam Accelerator Facility (CEBAF) as shown in an aerial photograph in Figure 1. Jefferson Lab was created in 1984 as CEBAF and started operations for physics in 1995. The accelerator uses superconducting radio-frequency (srf) techniques to generate high-quality beams of electrons with high-intensity, well-controlled polarization. Themore » technology has enabled ancillary facilities to be created. The CEBAF facility is used by an international user community of more than 1200 physicists for a program of exploration and study of nuclear, hadronic matter, the strong interaction and quantum chromodynamics. Additionally, the exceptional quality of the beams facilitates studies of the fundamental symmetries of nature, which complement those of atomic physics on the one hand and of high-energy particle physics on the other. The facility is in the midst of a project to double the energy of the facility and to enhance and expand its experimental facilities. Studies are also pursued with a Free-Electron Laser produced by an energy-recovering linear accelerator.« less

The Sidereal Time Variations of the Lorentz Force and Maximum Attainable Speed of Electrons

NASA Astrophysics Data System (ADS)

Nowak, Gabriel; Wojtsekhowski, Bogdan; Roblin, Yves; Schmookler, Barak

2016-09-01

The Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab produces electrons that orbit through a known magnetic system. The electron beam's momentum can be determined through the radius of the beam's orbit. This project compares the beam orbit's radius while travelling in a transverse magnetic field with theoretical predictions from special relativity, which predict a constant beam orbit radius. Variations in the beam orbit's radius are found by comparing the beam's momentum entering and exiting a magnetic arc. Beam position monitors (BPMs) provide the information needed to calculate the beam momentum. Multiple BPM's are included in the analysis and fitted using the method of least squares to decrease statistical uncertainty. Preliminary results from data collected over a 24 hour period show that the relative momentum change was less than 10-4. Further study will be conducted including larger time spans and stricter cuts applied to the BPM data. The data from this analysis will be used in a larger experiment attempting to verify special relativity. While the project is not traditionally nuclear physics, it involves the same technology (the CEBAF accelerator) and the same methods (ROOT) as a nuclear physics experiment. DOE SULI Program.

EuCARD 2010: European coordination of accelerator research and development

NASA Astrophysics Data System (ADS)

Romaniuk, Ryszard S.

2010-09-01

Accelerators are basic tools of the experimental physics of elementary particles, nuclear physics, light sources of the fourth generation. They are also used in myriad other applications in research, industry and medicine. For example, there are intensely developed transmutation techniques for nuclear waste from nuclear power and atomic industries. The European Union invests in the development of accelerator infrastructures inside the framework programs to build the European Research Area. The aim is to build new accelerator research infrastructures, develop the existing ones, and generally make the infrastructures more available to competent users. The paper summarizes the first year of activities of the EU FP7 Project Capacities EuCARD -European Coordination of Accelerator R&D. EuCARD is a common venture of 37 European Accelerator Laboratories, Institutes, Universities and Industrial Partners involved in accelerator sciences and technologies. The project, initiated by ESGARD, is an Integrating Activity co-funded by the European Commission under Framework Program 7 - Capacities for a duration of four years, starting April 1st, 2009. Several teams from this country participate actively in this project. The contribution from Polish research teams concerns: photonic and electronic measurement - control systems, RF-gun co-design, thin-film superconducting technology, superconducting transport infrastructures, photon and particle beam measurements and control.

Particle tracking acceleration via signed distance fields in direct-accelerated geometry Monte Carlo

DOE PAGES

Shriwise, Patrick C.; Davis, Andrew; Jacobson, Lucas J.; ...

2017-08-26

Computer-aided design (CAD)-based Monte Carlo radiation transport is of value to the nuclear engineering community for its ability to conduct transport on high-fidelity models of nuclear systems, but it is more computationally expensive than native geometry representations. This work describes the adaptation of a rendering data structure, the signed distance field, as a geometric query tool for accelerating CAD-based transport in the direct-accelerated geometry Monte Carlo toolkit. Demonstrations of its effectiveness are shown for several problems. The beginnings of a predictive model for the data structure's utilization based on various problem parameters is also introduced.

Ion beams provided by small accelerators for material synthesis and characterization

NASA Astrophysics Data System (ADS)

Mackova, Anna; Havranek, Vladimir

2017-06-01

The compact, multipurpose electrostatic tandem accelerators are extensively used for production of ion beams with energies in the range from 400 keV to 24 MeV of almost all elements of the periodic system for the trace element analysis by means of nuclear analytical methods. The ion beams produced by small accelerators have a broad application, mainly for material characterization (Rutherford Back-Scattering spectrometry, Particle Induced X ray Emission analysis, Nuclear Reaction Analysis and Ion-Microprobe with 1 μm lateral resolution among others) and for high-energy implantation. Material research belongs to traditionally progressive fields of technology. Due to the continuous miniaturization, the underlying structures are far beyond the analytical limits of the most conventional methods. Ion Beam Analysis (IBA) techniques provide this possibility as they use probes of similar or much smaller dimensions (particles, radiation). Ion beams can be used for the synthesis of new progressive functional nanomaterials for optics, electronics and other applications. Ion beams are extensively used in studies of the fundamental energetic ion interaction with matter as well as in the novel nanostructure synthesis using ion beam irradiation in various amorphous and crystalline materials in order to get structures with extraordinary functional properties. IBA methods serve for investigation of materials coming from material research, industry, micro- and nano-technology, electronics, optics and laser technology, chemical, biological and environmental investigation in general. Main research directions in laboratories employing small accelerators are also the preparation and characterization of micro- and nano-structured materials which are of interest for basic and oriented research in material science, and various studies of biological, geological, environmental and cultural heritage artefacts are provided too.

A new ion beam facility based on a 3 MV Tandetron™ at IFIN-HH, Romania

NASA Astrophysics Data System (ADS)

Burducea, I.; Straticiuc, M.; Ghiță, D. G.; Moșu, D. V.; Călinescu, C. I.; Podaru, N. C.; Mous, D. J. W.; Ursu, I.; Zamfir, N. V.

2015-09-01

A 3 MV Tandetron™ accelerator system has been installed and commissioned at the "Horia Hulubei" National Institute for Physics and Nuclear Engineering - IFIN-HH, Măgurele, Romania. The main purpose of this machine is to strengthen applied nuclear physics research ongoing in our institute for more than four decades. The accelerator system was developed by High Voltage Engineering Europa B.V. (HVE) and comprises three high energy beam lines. The first beam line is dedicated to ion beam analysis (IBA) techniques: Rutherford Backscattering Spectrometry - RBS, Nuclear Reaction Analysis - NRA, Particle Induced X-ray and γ-ray Emission - PIXE and PIGE and micro-beam experiments - μ-PIXE. The second beam line is dedicated to high energy ion implantation experiments and the third beam line was designed mainly for nuclear cross-sections measurements used in nuclear astrophysics. A unique feature, the first time in operation at an accelerator facility is the Na charge exchange canal (CEC), which is used to obtain high intensity beams of He- of at least 3 μA. The results of the acceptance tests demonstrate the huge potential of this new facility in various fields, from IBA to radiation hardness studies and from medical or environmental applications to astrophysics. The main features of the accelerator are presented in this paper.

Treatment Planning for Accelerator-Based Boron Neutron Capture Therapy

NASA Astrophysics Data System (ADS)

Herrera, María S.; González, Sara J.; Minsky, Daniel M.; Kreiner, Andrés J.

2010-08-01

Glioblastoma multiforme and metastatic melanoma are frequent brain tumors in adults and presently still incurable diseases. Boron Neutron Capture Therapy (BNCT) is a promising alternative for this kind of pathologies. Accelerators have been proposed for BNCT as a way to circumvent the problem of siting reactors in hospitals and for their relative simplicity and lower cost among other advantages. Considerable effort is going into the development of accelerator-based BNCT neutron sources in Argentina. Epithermal neutron beams will be produced through appropriate proton-induced nuclear reactions and optimized beam shaping assemblies. Using these sources, computational dose distributions were evaluated in a real patient with diagnosed glioblastoma treated with BNCT. The simulated irradiation was delivered in order to optimize dose to the tumors within the normal tissue constraints. Using Monte Carlo radiation transport calculations, dose distributions were generated for brain, skin and tumor. Also, the dosimetry was studied by computing cumulative dose-volume histograms for volumes of interest. The results suggest acceptable skin average dose and a significant dose delivered to tumor with low average whole brain dose for irradiation times less than 60 minutes, indicating a good performance of an accelerator-based BNCT treatment.

Treatment Planning for Accelerator-Based Boron Neutron Capture Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herrera, Maria S.; Gonzalez, Sara J.; Minsky, Daniel M.

2010-08-04

Glioblastoma multiforme and metastatic melanoma are frequent brain tumors in adults and presently still incurable diseases. Boron Neutron Capture Therapy (BNCT) is a promising alternative for this kind of pathologies. Accelerators have been proposed for BNCT as a way to circumvent the problem of siting reactors in hospitals and for their relative simplicity and lower cost among other advantages. Considerable effort is going into the development of accelerator-based BNCT neutron sources in Argentina. Epithermal neutron beams will be produced through appropriate proton-induced nuclear reactions and optimized beam shaping assemblies. Using these sources, computational dose distributions were evaluated in a realmore » patient with diagnosed glioblastoma treated with BNCT. The simulated irradiation was delivered in order to optimize dose to the tumors within the normal tissue constraints. Using Monte Carlo radiation transport calculations, dose distributions were generated for brain, skin and tumor. Also, the dosimetry was studied by computing cumulative dose-volume histograms for volumes of interest. The results suggest acceptable skin average dose and a significant dose delivered to tumor with low average whole brain dose for irradiation times less than 60 minutes, indicating a good performance of an accelerator-based BNCT treatment.« less

Particle Accelerator Focus Automation

NASA Astrophysics Data System (ADS)

Lopes, José; Rocha, Jorge; Redondo, Luís; Cruz, João

2017-08-01

The Laboratório de Aceleradores e Tecnologias de Radiação (LATR) at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST) has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+) and proton (H+) beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

Summary of sessions on nuclear astrophysics

NASA Astrophysics Data System (ADS)

Rolfs, C.

In the minds of some there exists the patronizing belief that nuclear physics is a mature science. The same is not believed about nuclear astrophysics, which has been an active branch of astrophysics for over fifty years, but is now in the midst of an exciting revival in experimental and theoretical research around the world. The ultimate goal is to understand how nuclear processes generate the energy of stars over their lifetimes and, in doing so, synthesize heavier elements from the primordial hydrogen and helium produced in the Big Bang, which led to the expanding universe. Impressive progress has been made in this goal and this was rewarded. However, there are major puzzles, such as the solar neutrino problem to name just one, which challenge the fundaments of the field. To solve these problems, new nuclear physics data are needed employing novel experimental techniques such as radioactive ion beams and underground accelerator facilities. Without such new data, much of the work done so far will - in an optimistic view - be incomplete and - in a pessimistic view - be possibly wrong. Thus, new data do not represent a fine structure information or a cleaning-up job, but they represent the major next step in this exciting field&

Development and test of a cryogenic trap system dedicated to confinement of radioactive volatile isotopes in SPIRAL2 post-accelerator

NASA Astrophysics Data System (ADS)

Souli, M.; Dolégiéviez, P.; Fadil, M.; Gallardo, P.; Levallois, R.; Munoz, H.; Ozille, M.; Rouillé, G.; Galet, F.

2011-12-01

A cryogenic trap system called Cryotrap has been studied and developed in the framework of nuclear safety studies for SPIRAL2 accelerator. The main objective of Cryotrap is to confine and reduce strongly the migration of radioactive volatile isotopes in beam lines. These radioactive gases are produced after interaction between a deuteron beam and a fissile target. Mainly, Cryotrap is composed by a vacuum vessel and two copper thermal screens maintained separately at two temperatures T1=80 K and T2=20 K. A Cryocooler with two stages at previous temperatures is used to remove static heat losses of the cryostat and ensure an efficient cooling of the system. Due to strong radiological constraints that surround Cryotrap, the coupling system between Cryocooler and thermal screens is based on aluminum thermo-mechanical contraction. The main objective of this original design is to limit direct human maintenance interventions and provide maximum automated operations. A preliminary prototype of Cryotrap has been developed and tested at GANIL laboratory to validate its design, and determine its thermal performance and trapping efficiency. In this paper, we will first introduce briefly SPIRAL2 project and discuss the main role of Cryotrap in nuclear safety of the accelerator. Then, we will describe the proposed conceptual design of Cryotrap and its main characteristics. After that, we will focus on test experiment and analyze experimental data. Finally, we will present preliminary results of gas trapping efficiency tests.

Physics through the 1990s: Nuclear physics

NASA Technical Reports Server (NTRS)

1986-01-01

The volume begins with a non-mathematical introduction to nuclear physics. A description of the major advances in the field follows, with chapters on nuclear structure and dynamics, fundamental forces in the nucleus, and nuclei under extreme conditions of temperature, density, and spin. Impacts of nuclear physics on astrophysics and the scientific and societal benefits of nuclear physics are then discussed. Another section deals with scientific frontiers, describing research into the realm of the quark-gluon plasma; the changing description of nuclear matter, specifically the use of the quark model; and the implications of the standard model and grand unified theories of elementary-particle physics; and finishes with recommendations and priorities for nuclear physics research facilities, instrumentation, accelerators, theory, education, and data bases. Appended are a list of national accelerator facilities, a list of reviewers, a bibliography, and a glossary.

Low Cost Nuclear Thermal Rocket Cermet Fuel Element Environment Testing

NASA Technical Reports Server (NTRS)

Bradley, David E.; Mireles, Omar R.; Hickman, Robert R.

2011-01-01

Deep space missions with large payloads require high specific impulse (Isp) and relatively high thrust in order to achieve mission goals in reasonable time frames. Conventional, storable propellants produce average Isp. Nuclear thermal rockets (NTR) capable of high Isp thrust have been proposed. NTR employs heat produced by fission reaction to heat and therefore accelerate hydrogen which is then forced through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000K) and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high temperature hydrogen exposure on fuel elements is limited. The primary concern is the mechanical failure of fuel elements which employ high-melting-point metals, ceramics or a combination (cermet) as a structural matrix into which the nuclear fuel is distributed. It is not necessary to include fissile material in test samples intended to explore high temperature hydrogen exposure of the structural support matrices. A small-scale test bed designed to heat fuel element samples via non-contact RF heating and expose samples to hydrogen is being developed to assist in optimal material and manufacturing process selection without employing fissile material. This paper details the test bed design and results of testing conducted to date.

Operator evolution for ab initio electric dipole transitions of 4He

DOE PAGES

Schuster, Micah D.; Quaglioni, Sofia; Johnson, Calvin W.; ...

2015-07-24

A goal of nuclear theory is to make quantitative predictions of low-energy nuclear observables starting from accurate microscopic internucleon forces. A major element of such an effort is applying unitary transformations to soften the nuclear Hamiltonian and hence accelerate the convergence of ab initio calculations as a function of the model space size. The consistent simultaneous transformation of external operators, however, has been overlooked in applications of the theory, particularly for nonscalar transitions. We study the evolution of the electric dipole operator in the framework of the similarity renormalization group method and apply the renormalized matrix elements to the calculationmore » of the 4He total photoabsorption cross section and electric dipole polarizability. All observables are calculated within the ab initio no-core shell model. Furthermore, we find that, although seemingly small, the effects of evolved operators on the photoabsorption cross section are comparable in magnitude to the correction produced by including the chiral three-nucleon force and cannot be neglected.« less

Low temperature synthesis and sintering of d-UO2 nanoparticles.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nenoff, Tina Maria; Ferreira, Summer Rhodes; Robinson, David B.

We report on the novel room temperature method of synthesizing advanced nuclear fuels; a method that virtually eliminates any volatility of components. This process uses radiolysis to form stable nanoparticle (NP) nuclear transuranic (TRU) fuel surrogates and in-situ heated stage TEM to sinter the NPs. The radiolysis is performed at Sandia's Gamma Irradiation Facility (GIF) 60Co source (3 x 10{sup 6} rad/hr). Using this method, sufficient quantities of fuels for research purposes can be produced for accelerated advanced nuclear fuel development. We are focused on both metallic and oxide alloy nanoparticles of varying compositions, in particular d-U, d-U/La alloys andmore » d-UO2 NPs. We present detailed descriptions of the synthesis procedures, the characterization of the NPs, the sintering of the NPs, and their stability with temperature. We have employed UV-vis, HRTEM, HAADF-STEM imaging, single particle EDX and EFTEM mapping characterization techniques to confirm the composition and alloying of these NPs.« less

Nuclear physics for materials technology

NASA Astrophysics Data System (ADS)

Conlon, T. W.

1987-04-01

Although particle accelerators have traditionally been used to further our knowledge of nuclear physics, the last decade or so has seen a rapid growth of their involvement in materials technology — both to modify materials and to provide analytical information at the atomic level that cannot be obtained in other ways. The deployment of ion beams in these areas has occurred in three phases: first the exploitation of keV ion beams (in ion implantation and SIMS) then MeV light ion beams (using RBS, NRA, PIXE analysis and TLA) and currently MeV heavy ion beams, together with the associated fast recoil atoms and nuclei that they produce in interactions with materials. This trend has been accompanied by the gradual assimilation of methods such as energy analysis, microbeam focussing, particle identification, time of flight and coincidence techniques, etc., which were first developed for experimental nuclear physics use. Current examples of developments in the MeV range relevant to phases 2 and 3 are given.

Los Alamos Neutron Science Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kippen, Karen Elizabeth

For more than 30 years the Los Alamos Neutron Science Center (LANSCE) has provided the scientific underpinnings in nuclear physics and material science needed to ensure the safety and surety of the nuclear stockpile into the future. In addition to national security research, the LANSCE User Facility has a vibrant research program in fundamental science, providing the scientific community with intense sources of neutrons and protons to perform experiments supporting civilian research and the production of medical and research isotopes. Five major experimental facilities operate simultaneously. These facilities contribute to the stockpile stewardship program, produce radionuclides for medical testing, andmore » provide a venue for industrial users to irradiate and test electronics. In addition, they perform fundamental research in nuclear physics, nuclear astrophysics, materials science, and many other areas. The LANSCE User Program plays a key role in training the next generation of top scientists and in attracting the best graduate students, postdoctoral researchers, and early-career scientists. The U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA) —the principal sponsor of LANSCE—works with the Office of Science and the Office of Nuclear Energy, which have synergistic long-term needs for the linear accelerator and the neutron science that is the heart of LANSCE.« less

Progress of the Felsenkeller Shallow-Underground Accelerator for Nuclear Astrophysics

NASA Astrophysics Data System (ADS)

Bemmerer, D.; Cavanna, F.; Cowan, T. E.; Grieger, M.; Hensel, T.; Junghans, A. R.; Ludwig, F.; Müller, S. E.; Rimarzig, B.; Reinicke, S.; Schulz, S.; Schwengner, R.; Stöckel, K.; Szücs, T.; Takács, M. P.; Wagner, A.; Wagner, L.; Zuber, K.

Low-background experiments with stable ion beams are an important tool for putting the model of stellar hydrogen, helium, and carbon burning on a solid experimental foundation. The pioneering work in this regard has been done by the LUNA collaboration at Gran Sasso, using a 0.4 MV accelerator. In the present contribution, the status of the project for a higher-energy underground accelerator is reviewed. Two tunnels of the Felsenkeller underground site in Dresden, Germany, are currently being refurbished for the installation of a 5 MV high-current Pelletron accelerator. Construction work is on schedule and expected to complete in August 2017. The accelerator will provide intense, 50 µA, beams of 1H+, 4He+, and 12C+ ions, enabling research on astrophysically relevant nuclear reactions with unprecedented sensitivity.

A new IBA-AMS laboratory at the Comenius University in Bratislava (Slovakia)

NASA Astrophysics Data System (ADS)

Povinec, Pavel P.; Masarik, Jozef; Kúš, Peter; Holý, Karol; Ješkovský, Miroslav; Breier, Robert; Staníček, Jaroslav; Šivo, Alexander; Richtáriková, Marta; Kováčik, Andrej; Szarka, Ján; Steier, Peter; Priller, Alfred

2015-01-01

A Centre for Nuclear and Accelerator Technologies (CENTA) has been established at the Comenius University in Bratislava comprising of a tandem laboratory designed for Ion Beam Analysis (IBA), Ion Beam Modification (IBM) of materials and Accelerator Mass Spectrometry (AMS). The main equipment of the laboratory, i.e. Alphatross and MC-SNICS ion sources, 3 MV Pelletron tandem accelerator, and analyzers of accelerated ions are described. Optimization of ion beam characteristics for different ion sources with gas and solid targets, for transmission of accelerated ions with different energy and charge state, for different parameters of the high-energy ion analyzers, as well as first AMS results are presented. The scientific program of the CENTA will be devoted mainly to nuclear, environmental, life and material sciences.

Development of an EBIS charge breeder for the Rare Isotope Science Project

NASA Astrophysics Data System (ADS)

Son, Hyock-Jun; Park, Young-Ho; Kondrashev, Sergey; Kim, Jongwon; Lee, Bong Ju; Chung, Moses

2017-10-01

In Korea, a heavy ion accelerator facility called RAON is being designed to produce various rare isotopes for the Rare Isotope Science Project (RISP) (Jeong, 2016) [1], (Moon, 2014) [2]. This facility is designed to use both In-flight Fragment (IF) and Isotope Separation On-Line (ISOL) techniques in order to produce a wide variety of RI beams for nuclear physics experiments. An Electron Beam Ion Source (EBIS) will be used for charge breeding of Rare Isotope (RI) beams in the ISOL system. The charge-to-mass ratio (q/A) of the RI beams after charge breeding is ≥1/4. The highly charged RI beams will be accelerated by a linac post-accelerator and delivered to a low energy (∼18 MeV/u) experimental hall or the IF system. The RAON EBIS will use a 3 A electron gun and a 6 T superconducting solenoid for high capacity, high efficiency, and short breeding time. In front of the charge breeder, an RFQ cooler-buncher will be used to deliver a bunched beam with small emittance to the EBIS charge breeder. The main design of the RAON EBIS has been carried out on the basis of several beam analyses and technical reviews. In this paper, current progress of the development of the RAON EBIS charge breeder will be presented.

Dynamic Compression Experiments on Hydrogen and Deuterium in the Warm Dense Liquid.

NASA Astrophysics Data System (ADS)

Desjarlais, Michael; McCoy, Chad; Cochrane, Kyle; Mattsson, Thomas; Knudson, Marcus; Redmer, Ronald

2017-06-01

Recently a shock-ramp platform has been developed on the Z Accelerator to access off-Hugoniot states in liquids. The accelerator delivers a two-step current pulse; the first accelerates the electrode to a constant velocity, which upon impact with the sample cell creates a well-defined shock, the subsequent current rise produces ramp compression from the initially shocked state producing relatively cool (1-2 kK), high pressure (>300 GPa), high compression (10 to 15-fold compression) states. This technique allows experimental access to the region of phase space where hydrogen is predicted to undergo a first-order phase transition from an insulating molecular-like to a conducting atomic-like liquid. Here we discuss the experimental platform, survey various theoretical predictions for the liquid-liquid, insulator-to-metal transition in hydrogen, and present results of experiments on both deuterium and hydrogen that clearly show an abrupt transition to a metallic state. We also present results from recent experiments at higher temperatures (3-4 kK) and compare the observations to both first-principles theory and previous step-wise loading experiments that exhibited a minimum metallic conductivity. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Educational activities with a tandem accelerator

NASA Astrophysics Data System (ADS)

Casolaro, P.; Campajola, L.; Balzano, E.; D'Ambrosio, E.; Figari, R.; Vardaci, E.; La Rana, G.

2018-05-01

Selected experiments in fundamental physics have been proposed for many years at the Tandem Accelerator of the University of Napoli ‘Federico II’s Department of Physics as a part of a one-semester laboratory course for graduate students. The aim of this paper is to highlight the educational value of the experimental realization of the nuclear reaction 19F(p,α)16O. With the purpose of verifying the mass-energy equivalence principle, different aspects of both classical and modern physics can be investigated, e.g. conservation laws, atomic models, nuclear physics applications to compositional analysis, nuclear cross-section, Q-value and nuclear spectroscopic analysis.

Deuteron nuclear data for the design of accelerator-based neutron sources: Measurement, model analysis, evaluation, and application

NASA Astrophysics Data System (ADS)

Watanabe, Yukinobu; Kin, Tadahiro; Araki, Shouhei; Nakayama, Shinsuke; Iwamoto, Osamu

2017-09-01

A comprehensive research program on deuteron nuclear data motivated by development of accelerator-based neutron sources is being executed. It is composed of measurements of neutron and gamma-ray yields and production cross sections, modelling of deuteron-induced reactions and code development, nuclear data evaluation and benchmark test, and its application to medical radioisotopes production. The goal of this program is to develop a state-of-the-art deuteron nuclear data library up to 200 MeV which will be useful for the design of future (d,xn) neutron sources. The current status and future plan are reviewed.

Felsenkeller shallow-underground accelerator laboratory for nuclear astrophysics

NASA Astrophysics Data System (ADS)

Bemmerer, D.; Cowan, T. E.; Gohl, S.; Ilgner, C.; Junghans, A. R.; Reinhardt, T. P.; Rimarzig, B.; Reinicke, S.; Röder, M.; Schmidt, K.; Schwengner, R.; Stöckel, K.; Szücs, T.; Takács, M.; Wagner, A.; Wagner, L.; Zuber, K.

2015-05-01

Favored by the low background in underground laboratories, low-background accelerator-based experiments are an important tool to study nuclear reactions involving stable charged particles. This technique has been used for many years with great success at the 0.4 MV LUNA accelerator in the Gran Sasso laboratory in Italy, proteced from cosmic rays by 1400 m of rock. However, the nuclear reactions of helium and carbon burning and the neutron source reactions for the astrophysical s-process require higher beam energies than those available at LUNA. Also the study of solar fusion reactions necessitates new data at higher energies. As a result, in the present NuPECC long range plan for nuclear physics in Europe, the installation of one or more higher-energy underground accelerators is strongly recommended. An intercomparison exercise has been carried out using the same HPGe detector in a typical nuclear astrophysics setup at several sites, including the Dresden Felsenkeller underground laboratory. It was found that its rock overburden of 45m rock, together with an active veto against the remaining muon flux, reduces the background to a level that is similar to the deep underground scenario. Based on this finding, a used 5 MV pelletron tandem with 250 μA upcharge current and external sputter ion source has been obtained and transported to Dresden. Work on an additional radio-frequency ion source on the high voltage terminal is underway. The project is now fully funded. The installation of the accelerator in the Felsenkeller is expected for the near future. The status of the project and the planned access possibilities for external users will be reported.

Positive Selection in Rapidly Evolving Plastid–Nuclear Enzyme Complexes

PubMed Central

Rockenbach, Kate; Havird, Justin C.; Monroe, J. Grey; Triant, Deborah A.; Taylor, Douglas R.; Sloan, Daniel B.

2016-01-01

Rates of sequence evolution in plastid genomes are generally low, but numerous angiosperm lineages exhibit accelerated evolutionary rates in similar subsets of plastid genes. These genes include clpP1 and accD, which encode components of the caseinolytic protease (CLP) and acetyl-coA carboxylase (ACCase) complexes, respectively. Whether these extreme and repeated accelerations in rates of plastid genome evolution result from adaptive change in proteins (i.e., positive selection) or simply a loss of functional constraint (i.e., relaxed purifying selection) is a source of ongoing controversy. To address this, we have taken advantage of the multiple independent accelerations that have occurred within the genus Silene (Caryophyllaceae) by examining phylogenetic and population genetic variation in the nuclear genes that encode subunits of the CLP and ACCase complexes. We found that, in species with accelerated plastid genome evolution, the nuclear-encoded subunits in the CLP and ACCase complexes are also evolving rapidly, especially those involved in direct physical interactions with plastid-encoded proteins. A massive excess of nonsynonymous substitutions between species relative to levels of intraspecific polymorphism indicated a history of strong positive selection (particularly in CLP genes). Interestingly, however, some species are likely undergoing loss of the native (heteromeric) plastid ACCase and putative functional replacement by a duplicated cytosolic (homomeric) ACCase. Overall, the patterns of molecular evolution in these plastid–nuclear complexes are unusual for anciently conserved enzymes. They instead resemble cases of antagonistic coevolution between pathogens and host immune genes. We discuss a possible role of plastid–nuclear conflict as a novel cause of accelerated evolution. PMID:27707788

Argonne Physics Division

Science.gov Websites

, nuclear structure and reaction research, nuclear theory, medium energy nuclear research and accelerator structure of baryonic matter in the universe - the matter that makes up stars, planets and human life itself

Investigation of 3He-induced reactions on natural Ti for nuclear analytical and radionuclide production purposes

NASA Astrophysics Data System (ADS)

Ditrói, F.; Tárkányi, F.; Ali, M. A.; Andó, L.; Heselius, S.-J.; Shubin, Yu.; Youxiang, Zhuang; Mustafa, M. G.

2000-07-01

Excitation Russian Federation functions of 3He-induced nuclear reactions producing 43,44m,46,47,48Sc, 48V, 48,49,51Cr were measured up to 36 MeV bombarding energy by using the stacked-foil technique on different medium-energy accelerators. The results were compared with the data (cross-section, thick-target yield, activity-distribution functions, …) from the literature, model calculations and other measurements. Earlier measurements at higher energies up to 135 MeV are also plotted to complete the database for 3He-reactions on natural Ti. The new experimental and literature data were compared with the predictions of different model calculations for the 48V producing reactions. The selected experimental data sets were fitted using different methods to obtain recommended values. The measurements and compilation proved, that the 3He induced reactions on natural titanium, especially those leading to 48V and 48Cr are especially useful for monitoring, for activation analysis and for Thin Layer Activation (TLA) purposes. Production of 48V as a radiotracer is also recommended.

An enhancement of NASTRAN for the seismic analysis of structures. [nuclear power plants

NASA Technical Reports Server (NTRS)

Burroughs, J. W.

1980-01-01

New modules, bulk data cards and DMAP sequence were added to NASTRAN to aid in the seismic analysis of nuclear power plant structures. These allow input consisting of acceleration time histories and result in the generation of acceleration floor response spectra. The resulting system contains numerous user convenience features, as well as being reasonably efficient.

High-power liquid-lithium jet target for neutron production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halfon, S.; Feinberg, G.; Racah Institute of Physics, Hebrew University, Jerusalem 91904

2013-12-15

A compact liquid-lithium target (LiLiT) was built and tested with a high-power electron gun at the Soreq Nuclear Research Center. The lithium target, to be bombarded by the high-intensity proton beam of the Soreq Applied Research Accelerator Facility (SARAF), will constitute an intense source of neutrons produced by the {sup 7}Li(p,n){sup 7}Be reaction for nuclear astrophysics research and as a pilot setup for accelerator-based Boron Neutron Capture Therapy. The liquid-lithium jet target acts both as neutron-producing target and beam dump by removing the beam thermal power (>5 kW, >1 MW/cm{sup 3}) with fast transport. The target was designed based onmore » a thermal model, accompanied by a detailed calculation of the {sup 7}Li(p,n) neutron yield, energy distribution, and angular distribution. Liquid lithium is circulated through the target loop at ∼200 °C and generates a stable 1.5 mm-thick film flowing at a velocity up to 7 m/s onto a concave supporting wall. Electron beam irradiation demonstrated that the liquid-lithium target can dissipate electron power areal densities of >4 kW/cm{sup 2} and volume power density of ∼2 MW/cm{sup 3} at a lithium flow of ∼4 m/s while maintaining stable temperature and vacuum conditions. The LiLiT setup is presently in online commissioning stage for high-intensity proton beam irradiation (1.91–2.5 MeV, 1–2 mA) at SARAF.« less

Producing Mono-energetic Neutrons for Research

NASA Astrophysics Data System (ADS)

Jepeal, Steven

2014-09-01

Free neutrons are seldom produced in nature and are unstable, decaying back to protons with a mean life of 881s. The only natural sources are spontaneous fission of actinides and cosmic ray interactions, both of which are rare processes. The detection of neutrons indicates unusual nuclear activity, allowing neutron detection the roll of the ``smoking gun'' for seeking potential nuclear terrorism. Recently, there has been a push for the development of new neutron detectors, ideally sufficiently inexpensive that a detector can be carried by all first responders such as police and fire fighters. One promising new material is the inorganic scintillator CLYC, a crystal of chlorine, lithium, yttrium and cesium. CLYC has a high energy resolution not only for gamma rays, but also for fast neutrons. At the University of Massachusetts, Lowell, CLYC is being developed in collaboration with local industrial companies. To evaluate its response to neutrons, in to 500 keV to 4 MeV energy range, the CN Van de Graaff generator is used to produce neutrons, via the 7Li(p,n)7Be reaction. However, the important energy regime of 4--10 MeV is currently inaccessible. This current project is to build a gas-cell target to enable the D(d,n)3He reaction and produce neutrons of energy up to 9 MeV, an approach that has been used successfully at the University of Kentucky. The project involves some mechanical engineering management, then chamber construction, vacuum testing, developing thin window technology, and finally commissioning of the gas cell using accelerated beams. The commissioning will be physics rich in quantifying the flux and energy resolution of the neutron beam produced. Free neutrons are seldom produced in nature and are unstable, decaying back to protons with a mean life of 881s. The only natural sources are spontaneous fission of actinides and cosmic ray interactions, both of which are rare processes. The detection of neutrons indicates unusual nuclear activity, allowing neutron detection the roll of the ``smoking gun'' for seeking potential nuclear terrorism. Recently, there has been a push for the development of new neutron detectors, ideally sufficiently inexpensive that a detector can be carried by all first responders such as police and fire fighters. One promising new material is the inorganic scintillator CLYC, a crystal of chlorine, lithium, yttrium and cesium. CLYC has a high energy resolution not only for gamma rays, but also for fast neutrons. At the University of Massachusetts, Lowell, CLYC is being developed in collaboration with local industrial companies. To evaluate its response to neutrons, in to 500 keV to 4 MeV energy range, the CN Van de Graaff generator is used to produce neutrons, via the 7Li(p,n)7Be reaction. However, the important energy regime of 4--10 MeV is currently inaccessible. This current project is to build a gas-cell target to enable the D(d,n)3He reaction and produce neutrons of energy up to 9 MeV, an approach that has been used successfully at the University of Kentucky. The project involves some mechanical engineering management, then chamber construction, vacuum testing, developing thin window technology, and finally commissioning of the gas cell using accelerated beams. The commissioning will be physics rich in quantifying the flux and energy resolution of the neutron beam produced. Made possible by the support of the Glynn Family Honors Program at the University of Notre Dame.

Accelerator shield design of KIPT neutron source facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhong, Z.; Gohar, Y.

Argonne National Laboratory (ANL) of the United States and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the design development of a neutron source facility at KIPT utilizing an electron-accelerator-driven subcritical assembly. Electron beam power is 100 kW, using 100 MeV electrons. The facility is designed to perform basic and applied nuclear research, produce medical isotopes, and train young nuclear specialists. The biological shield of the accelerator building is designed to reduce the biological dose to less than 0.5-mrem/hr during operation. The main source of the biological dose is the photons and the neutrons generatedmore » by interactions of leaked electrons from the electron gun and accelerator sections with the surrounding concrete and accelerator materials. The Monte Carlo code MCNPX serves as the calculation tool for the shield design, due to its capability to transport electrons, photons, and neutrons coupled problems. The direct photon dose can be tallied by MCNPX calculation, starting with the leaked electrons. However, it is difficult to accurately tally the neutron dose directly from the leaked electrons. The neutron yield per electron from the interactions with the surrounding components is less than 0.01 neutron per electron. This causes difficulties for Monte Carlo analyses and consumes tremendous computation time for tallying with acceptable statistics the neutron dose outside the shield boundary. To avoid these difficulties, the SOURCE and TALLYX user subroutines of MCNPX were developed for the study. The generated neutrons are banked, together with all related parameters, for a subsequent MCNPX calculation to obtain the neutron and secondary photon doses. The weight windows variance reduction technique is utilized for both neutron and photon dose calculations. Two shielding materials, i.e., heavy concrete and ordinary concrete, were considered for the shield design. The main goal is to maintain the total dose outside the shield boundary at less than 0.5-mrem/hr. The shield configuration and parameters of the accelerator building have been determined and are presented in this paper. (authors)« less

Comparison between Theoretical Calculation and Experimental Results of Excitation Functions for Production of Relevant Biomedical Radionuclides

NASA Astrophysics Data System (ADS)

Menapace, E.; Birattari, C.; Bonardi, M. L.; Groppi, F.; Morzenti, S.; Zona, C.

2005-05-01

The radionuclide production for biomedical applications has been brought up in the years, as a special nuclear application, at INFN LASA Laboratory, particularly in co-operation with the JRC-Ispra of EC. Mainly scientific aspects concerning radiation detection and the relevant instruments, the measurements of excitation functions of the involved nuclear reactions, the requested radiochemistry studies and further applications have been investigated. On the side of the nuclear data evaluations, based on nuclear model calculations and critically selected experimental data, the appropriate competence has been developed at ENEA Division for Advanced Physics Technologies. A series of high specific activity accelerator-produced radionuclides in no-carrier-added (NCA) form, for uses in metabolic radiotherapy and for PET radiodiagnostics, are investigated. In this work, last revised measurements and model calculations are reviewed for excitation functions of natZn(d,X)64Cu, 66Ga reactions, referring to irradiation experiments at K=38 variable energy Cyclotron of JRC-Ispra. Concerning the reaction data for producing 186gRe and 211At/211gPo (including significant emission spectra) and 210At, most recent and critically selected experimental results are considered and discussed in comparison with model calculations paying special care to pre-equilibrium effects estimate and to the appropriate overall parameterization. Model calculations are presented for 226Ra(p,2n)225Ac reaction, according to the working program of the ongoing IAEA CRP on the matter.

Comparison between Theoretical Calculation and Experimental Results of Excitation Functions for Production of Relevant Biomedical Radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menapace, E.; Birattari, C.; Bonardi, M.L.

The radionuclide production for biomedical applications has been brought up in the years, as a special nuclear application, at INFN LASA Laboratory, particularly in co-operation with the JRC-Ispra of EC. Mainly scientific aspects concerning radiation detection and the relevant instruments, the measurements of excitation functions of the involved nuclear reactions, the requested radiochemistry studies and further applications have been investigated. On the side of the nuclear data evaluations, based on nuclear model calculations and critically selected experimental data, the appropriate competence has been developed at ENEA Division for Advanced Physics Technologies. A series of high specific activity accelerator-produced radionuclides inmore » no-carrier-added (NCA) form, for uses in metabolic radiotherapy and for PET radiodiagnostics, are investigated. In this work, last revised measurements and model calculations are reviewed for excitation functions of natZn(d,X)64Cu, 66Ga reactions, referring to irradiation experiments at K=38 variable energy Cyclotron of JRC-Ispra. Concerning the reaction data for producing 186gRe and 211At/211gPo (including significant emission spectra) and 210At, most recent and critically selected experimental results are considered and discussed in comparison with model calculations paying special care to pre-equilibrium effects estimate and to the appropriate overall parameterization. Model calculations are presented for 226Ra(p,2n)225Ac reaction, according to the working program of the ongoing IAEA CRP on the matter.« less

Monte Carlo simulation of the operational quantities at the realistic mixed neutron-photon radiation fields CANEL and SIGMA.

PubMed

Lacoste, V; Gressier, V

2007-01-01

The Institute for Radiological Protection and Nuclear Safety owns two facilities producing realistic mixed neutron-photon radiation fields, CANEL, an accelerator driven moderator modular device, and SIGMA, a graphite moderated americium-beryllium assembly. These fields are representative of some of those encountered at nuclear workplaces, and the corresponding facilities are designed and used for calibration of various instruments, such as survey meters, personal dosimeters or spectrometric devices. In the framework of the European project EVIDOS, irradiations of personal dosimeters were performed at CANEL and SIGMA. Monte Carlo calculations were performed to estimate the reference values of the personal dose equivalent at both facilities. The Hp(10) values were calculated for three different angular positions, 0 degrees, 45 degrees and 75 degrees, of an ICRU phantom located at the position of irradiation.

Nuclear lamina defects cause ATM-dependent NF-κB activation and link accelerated aging to a systemic inflammatory response.

PubMed

Osorio, Fernando G; Bárcena, Clea; Soria-Valles, Clara; Ramsay, Andrew J; de Carlos, Félix; Cobo, Juan; Fueyo, Antonio; Freije, José M P; López-Otín, Carlos

2012-10-15

Alterations in the architecture and dynamics of the nuclear lamina have a causal role in normal and accelerated aging through both cell-autonomous and systemic mechanisms. However, the precise nature of the molecular cues involved in this process remains incompletely defined. Here we report that the accumulation of prelamin A isoforms at the nuclear lamina triggers an ATM- and NEMO-dependent signaling pathway that leads to NF-κB activation and secretion of high levels of proinflammatory cytokines in two different mouse models of accelerated aging (Zmpste24(-/-) and Lmna(G609G/G609G) mice). Causal involvement of NF-κB in accelerated aging was demonstrated by the fact that both genetic and pharmacological inhibition of NF-κB signaling prevents age-associated features in these animal models, significantly extending their longevity. Our findings provide in vivo proof of principle for the feasibility of pharmacological modulation of the NF-κB pathway to slow down the progression of physiological and pathological aging.

Neutron physics with accelerators

NASA Astrophysics Data System (ADS)

Colonna, N.; Gunsing, F.; Käppeler, F.

2018-07-01

Neutron-induced nuclear reactions are of key importance for a variety of applications in basic and applied science. Apart from nuclear reactors, accelerator-based neutron sources play a major role in experimental studies, especially for the determination of reaction cross sections over a wide energy span from sub-thermal to GeV energies. After an overview of present and upcoming facilities, this article deals with state-of-the-art detectors and equipment, including the often difficult sample problem. These issues are illustrated at selected examples of measurements for nuclear astrophysics and reactor technology with emphasis on their intertwined relations.

Activities of the DOE Nuclear Criticality Safety Program (NCSP) at the Oak Ridge Electron Linear Accelerator (ORELA)

NASA Astrophysics Data System (ADS)

Valentine, Timothy E.; Leal, Luiz C.; Guber, Klaus H.

2002-12-01

The Department of Energy established the Nuclear Criticality Safety Program (NCSP) in response to the Recommendation 97-2 by the Defense Nuclear Facilities Safety Board. The NCSP consists of seven elements of which nuclear data measurements and evaluations is a key component. The intent of the nuclear data activities is to provide high resolution nuclear data measurements that are evaluated, validated, and formatted for use by the nuclear criticality safety community to provide improved and reliable calculations for nuclear criticality safety evaluations. High resolution capture, fission, and transmission measurements are performed at the Oak Ridge Electron Linear Accelerator (ORELA) to address the needs of the criticality safety community and to address known deficiencies in nuclear data evaluations. The activities at ORELA include measurements on both light and heavy nuclei and have been used to identify improvements in measurement techniques that greatly improve the measurement of small capture cross sections. The measurement activities at ORELA provide precise and reliable high-resolution nuclear data for the nuclear criticality safety community.

Coulomb Excitation of the N = 50 nucleus 80Zn

NASA Astrophysics Data System (ADS)

van de Walle, J.; Aksouh, F.; Ames, F.; Behrens, T.; Bildstein, V.; Blazhev, A.; Cederkäll, J.; Clément, E.; Cocolios, T. E.; Davinson, T.; Delahaye, P.; Eberth, J.; Ekström, A.; Fedorov, D. V.; Fedosseev, V. N.; Fraile, L. M.; Franchoo, S.; Gernhauser, R.; Georgiev, G.; Habs, D.; Heyde, K.; Huber, G.; Huyse, M.; Ibrahim, F.; Ivanov, O.; Iwanicki, J.; Jolie, J.; Kester, O.; Köster, U.; Kröll, T.; Krücken, R.; Lauer, M.; Lisetskiy, A. F.; Lutter, R.; Marsh, B. A.; Mayet, P.; Niedermaier, O.; Nilsson, T.; Pantea, M.; Perru, O.; Raabe, R.; Reiter, P.; Sawicka, M.; Scheit, H.; Schrieder, G.; Schwalm, D.; Seliverstov, M. D.; Sieber, T.; Sletten, G.; Smirnova, N.; Stanoiu, M.; Stefanescu, I.; Thomas, J.-C.; Valiente-Dobón, J. J.; van Duppen, P.; Verney, D.; Voulot, D.; Warr, N.; Weisshaar, D.; Wenander, F.; Wolf, B. H.; Zielińska, M.

2008-05-01

Neutron rich Zinc isotopes, including the N = 50 nucleus 80Zn, were produced and post-accelerated at the Radioactive Ion Beam (RIB) facility REX-ISOLDE (CERN). Low-energy Coulomb excitation was induced on these isotopes after post-acceleration, yielding B(E2) strengths to the first excited 2+ states. For the first time, an excited state in 80Zn was observed and the 21+ state in 78Zn was established. The measured B(E2,21+-->01+) values are compared to two sets of large scale shell model calculations. Both calculations reproduce the observed B(E2) systematics for the full Zinc isotopic chain. The results for N = 50 isotones indicate a good N = 50 shell closure and a strong Z = 28 proton core polarization. The new results serve as benchmarks to establish theoretical models, predicting the nuclear properties of the doubly magic nucleus 78Ni.

DIANA - A deep underground accelerator for nuclear astrophysics experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winklehner, Daniel; Leitner, Daniela; Lemut, Alberto

DIANA (Dakota Ion Accelerator for Nuclear Astrophysics) is a proposed facility designed to be operated deep underground. The DIANA collaboration includes nuclear astrophysics groups from Lawrence Berkeley National Laboratory, Michigan State University, Western Michigan University, Colorado School of Mines, and the University of North Carolina, and is led by the University of Notre Dame. The scientific goals of the facility are measurements of low energy nuclear cross-sections associated with sun and pre-supernova stars in a laboratory setup at energies that are close to those in stars. Because of the low stellar temperatures associated with these environments, and the high Coulombmore » barrier, the reaction cross-sections are extremely low. Therefore these measurements are hampered by small signal to background ratios. By going underground the background due to cosmic rays can be reduced by several orders of magnitude. We report on the design status of the DIANA facility with focus on the 3 MV electrostatic accelerator.« less

Ion Beam Materials Analysis and Modifications at keV to MeV Energies at the University of North Texas

NASA Astrophysics Data System (ADS)

Rout, Bibhudutta; Dhoubhadel, Mangal S.; Poudel, Prakash R.; Kummari, Venkata C.; Lakshantha, Wickramaarachchige J.; Manuel, Jack E.; Bohara, Gyanendra; Szilasi, Szabolcs Z.; Glass, Gary A.; McDaniel, Floyd D.

2014-02-01

The University of North Texas (UNT) Ion Beam Modification and Analysis Laboratory (IBMAL) has four particle accelerators including a National Electrostatics Corporation (NEC) 9SDH-2 3 MV tandem Pelletron, a NEC 9SH 3 MV single-ended Pelletron, and a 200 kV Cockcroft-Walton. A fourth HVEC AK 2.5 MV Van de Graaff accelerator is presently being refurbished as an educational training facility. These accelerators can produce and accelerate almost any ion in the periodic table at energies from a few keV to tens of MeV. They are used to modify materials by ion implantation and to analyze materials by numerous atomic and nuclear physics techniques. The NEC 9SH accelerator was recently installed in the IBMAL and subsequently upgraded with the addition of a capacitive-liner and terminal potential stabilization system to reduce ion energy spread and therefore improve spatial resolution of the probing ion beam to hundreds of nanometers. Research involves materials modification and synthesis by ion implantation for photonic, electronic, and magnetic applications, micro-fabrication by high energy (MeV) ion beam lithography, microanalysis of biomedical and semiconductor materials, development of highenergy ion nanoprobe focusing systems, and educational and outreach activities. An overview of the IBMAL facilities and some of the current research projects are discussed.

Mirror symmetric optics design for charge-stripping section in Rare Isotope Science Project

NASA Astrophysics Data System (ADS)

Kim, Hye-Jin; Kim, Hyung-Jin; Jeon, Dong-O.; Hwang, Ji-Gwang; Kim, Eun-San

2013-12-01

The main aim of the Rare Isotope Science Project is to construct a high power heavy-ion accelerator based on the superconducting linear accelerator (SCL). The heavy ion accelerator is a key research facility that will allow ground-breaking research into numerous facets of basic science, such as nuclear physics, astrophysics, atomic physics, life science, medicine and material science. The machine will provide a beam power of 400 kW with a 238U79+ beam of 8 pμA and 200 MeV/u. One of the critical components in the SCL is the charge stripper between the two segments, SCL1 and SCL2, of the SCL. The charge stripper removes electrons from the ion beams to enhance the acceleration efficiency in the subsequent SCL2. To improve the efficiency of acceleration and power in SCL2, the optimal energy of stripped ions in a solid carbon foil stripper was estimated using the code LISE++. The thickness of the solid carbon foil was 300 μg/m2. The charge stripping efficiency of the solid carbon stripper in the present study was approximately 87%. For charge selection from the ions produced by the solid carbon stripper, a dispersive section is needed down-stream of the foil. The designed optics for the dispersive section is based on the mirror-symmetric optics to minimize the effect of high-order aberrations.

High power ring methods and accelerator driven subcritical reactor application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tahar, Malek Haj

2016-08-07

High power proton accelerators allow providing, by spallation reaction, the neutron fluxes necessary in the synthesis of fissile material, starting from Uranium 238 or Thorium 232. This is the basis of the concept of sub-critical operation of a reactor, for energy production or nuclear waste transmutation, with the objective of achieving cleaner, safer and more efficient process than today’s technologies allow. Designing, building and operating a proton accelerator in the 500-1000 MeV energy range, CW regime, MW power class still remains a challenge nowadays. There is a limited number of installations at present achieving beam characteristics in that class, e.g.,more » PSI in Villigen, 590 MeV CW beam from a cyclotron, SNS in Oakland, 1 GeV pulsed beam from a linear accelerator, in addition to projects as the ESS in Europe, a 5 MW beam from a linear accelerator. Furthermore, coupling an accelerator to a sub-critical nuclear reactor is a challenging proposition: some of the key issues/requirements are the design of a spallation target to withstand high power densities as well as ensure the safety of the installation. These two domains are the grounds of the PhD work: the focus is on the high power ring methods in the frame of the KURRI FFAG collaboration in Japan: upgrade of the installation towards high intensity is crucial to demonstrate the high beam power capability of FFAG. Thus, modeling of the beam dynamics and benchmarking of different codes was undertaken to validate the simulation results. Experimental results revealed some major losses that need to be understood and eventually overcome. By developing analytical models that account for the field defects, one identified major sources of imperfection in the design of scaling FFAG that explain the important tune variations resulting in the crossing of several betatron resonances. A new formula is derived to compute the tunes and properties established that characterize the effect of the field imperfections on the transverse beam dynamics. The results obtained allow to develop a correction scheme to minimize the tune variations of the FFAG. This is the cornerstone of a new fixed tune non-scaling FFAG that represents a potential candidate for high power applications. As part of the developments towards high power at the KURRI FFAG, beam dynamics studies have to account for space charge effects. In that framework, models have been installed in the tracking code ZGOUBI to account for the self-interaction of the particles in the accelerator. Application to the FFAG studies is shown. Finally, one focused on the ADSR concept as a candidate to solve the problem of nuclear waste. In order to establish the accelerator requirements, one compared the performance of ADSR with other conventional critical reactors by means of the levelized cost of energy. A general comparison between the different accelerator technologies that can satisfy these requirements is finally presented. In summary, the main drawback of the ADSR technology is the high Levelized Cost Of Energy compared to other advanced reactor concepts that do not employ an accelerator. Nowadays, this is a show-stopper for any industrial application aiming at producing energy (without dealing with the waste problem). Besides, the reactor is not intrinsically safer than critical reactor concepts, given the complexity of managing the target interface between the accelerator and the reactor core.« less

Self-vapor cooled targets for production of I-123 at high current accelerators. [using Xe-123 production

NASA Technical Reports Server (NTRS)

Blue, J. W.; Scholz, K. L.; Sodd, V. J.

1974-01-01

The basic elements of the vapor cooled target system are shown. This system can be operated as a heat pipe or as a conventional condenser. The choice of target fluid is based on the specific nuclear reaction chosen to produce Xe-123. The reaction using I-127 was studied and shown to have a significant yield for bombarding energies from 47 to 63 MeV. The Cs-133 reaction is also included. Xenon-123 is applied to I-123 production in a purer form for thyroid studies.

Poster - Thur Eve - 02: Regulatory oversight of the robotic radiosurgery facilities.

PubMed

Broda, K

2012-07-01

Following a recent review of the Class II Nuclear Facilities and Prescribed Equipment Regulations and regulatory oversight of particle accelerators, the Canadian Nuclear Safety Commission (CNSC) has changed its policy concerning the regulation of particle accelerators. In November 2011, the CNSC began to exercise its regulatory authority with respect to all particle accelerators operating at a beam energy of 1 (one) MeV or greater. The CNSC already licences and inspects particle accelerators capable of operating at or above 10 MeV. The decision to now include low energy particle accelerators (i.e., those operating at or above 1 MeV) ensures adequate, uniform and consistent regulatory oversight for all Class II accelerators. The CNSC expects these facilities to comply with CNSC requirements by December 2013. Besides conventional linear accelerators of lower energy (6 MeV or below) typically found in cancer clinics, two types of equipment now fall under the CNSC's regulatory oversight as a result of the above change: robotic radiosurgery and tomotherapy equipment and facilities. A number of clinics in Canada already operates these types of equipment and facilities. The safety aspects of radiosurgery equipment differ slightly from those for conventional linear accelerators. This poster aims to present an approach taken by the CNSC to regulate robotic radiosurgery equipment and facilities. The presentation will explain how to meet regulatory requirements of the Class II Nuclear Facilities and Prescribed Equipment Regulations by licensees operating or planning to acquire these types of equipment and facilities. © 2012 American Association of Physicists in Medicine.

Ground-based simulations of cosmic ray heavy ion interactions in spacecraft and planetary habitat shielding materials

NASA Technical Reports Server (NTRS)

Miller, J.; Zeitlin, C.; Heilbronn, L.; Borak, T.; Carter, T.; Frankel, K. A.; Fukumura, A.; Murakami, T.; Rademacher, S. E.; Schimmerling, W.;

A Polarized Electron RF Photoinjector Using the Plane-Wave-Transformer (PWT) Design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clendenin, James E

Polarized electron beams are now in routine use in particle accelerators for nuclear and high energy physics experiments. These beams are presently produced by dc-biased photoelectron sources combined with rf chopping and bunching systems with inherently high transverse emittances. Low emittances can be produced with an rf gun, but the vacuum environment has until now been considered too harsh to support a negative electron affinity GaAs photocathode. We propose to significantly improve the vacuum conditions by adapting a PWT rf photoinjector to achieve reasonable cathode emission rates and lifetimes. This adaptation can also be combined with special optics that willmore » result in a flat beam with a normalized rms emittance in the narrow dimension that may be as low as 10{sup -8} m.« less

Accelerator driven reactors and nuclear waste management projects in the Czech Republic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janouch, Frantisek; Mach, Rostislav; Institute of Nuclear Physics, Rez near Prague

1995-09-15

The Czech Republic is almost the only country in the central Europe which continues with the construction of nuclear power reactors. Its small territory and dense population causes public worries concerning the disposal of the spent nuclear fuel. The Czech nuclear scientists and the power companies and the nuclear industries are therefore looking for alterative solutions. The Los Alamos ATW project had received a positive response in the Czech mass-media and even in the industrial and governmental quarters. The recent scientific symposium ''Accelerator driven reactors and nuclear waste management'' convened at the Liblice castle near Prague, 27-29.6. 1994 and sponsoredmore » by the Czech Energy Company CEZ, reviewed the competencies and experimental basis in the Czech republic and made the first attempt to formulate the national approach and to establish international collaboration in this area.« less

Accelerator driven reactors and nuclear waste management projects in the Czech Republic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janouch, F.; Mach, R.

1995-10-01

The Czech Republic is almost the only country in the central Europe which continues with the construction of nuclear power reactors. Its small territory and dense population causes public worries concerning the disposal of the spent nuclear fuel. The Czech nuclear scientists and the power companies and the nuclear industries are therefore looking for alternative solutions. The Los Alamos ATW project had received a positive response in the Czech mass-media and even in the industrial and governmental quarters. The recent scientific symposium {open_quotes}Accelerator driven reactors and nuclear waste management{close_quotes} convened at the Liblice castle near Prague, 27-29. 6. 1994 andmore » sponsored by the Czech Energy Company CEZ, reviewed the competencies and experimental basis in the Czech republic and made the first attempt to formulate the national approach and to establish international collaboration in this area.« less

Spallation processes and nuclear interaction products of cosmic rays.

PubMed

Silberberg, R; Tsao, C H

1990-08-01

Most cosmic-ray nuclei heavier than helium have suffered nuclear collisions in the interstellar gas, with transformation of nuclear composition. The isotopic and elemental composition at the sources has to be inferred from the observed composition near the Earth. The source composition permits tests of current ideas on sites of origin, nucleosynthesis in stars, evolution of stars, the mixing and composition of the interstellar medium and injection processes prior to acceleration. The effects of nuclear spallation, production of radioactive nuclides and the time dependence of their decay provide valuable information on the acceleration and propagation of cosmic rays, their nuclear transformations, and their confinement time in the Galaxy. The formation of spallation products that only decay by electron capture and are relatively long-lived permits an investigation of the nature and density fluctuations (like clouds) of the interstellar medium. Since nuclear collisions yield positrons, antiprotons, gamma rays and neutrinos, we shall discuss these topics briefly.

A study of commercially-available polyethylene terephthalate (PET) and polycarbonate as nuclear track detector materials

NASA Astrophysics Data System (ADS)

Espinosa, G.; Golzarri, J. I.; Vazquez-Lopez, C.; Trejo, R.; Lopez, K.; Rickards, J.

2014-07-01

In the study of the sensitivity of materials to be used as nuclear track detectors, it was found that commercial polyethylene terephthalate (PET) from Ciel® water bottles, commercial roof cover polycarbonate, and recycled packaging strips (recycled PET), can be used as nuclear track detectors. These three commercial materials present nuclear tracks when bombarded by 2.27 MeV nitrogen ions produced in a Pelletron particle accelerator, and by fission fragments from a 252Cf source (79.4 and 103.8 MeV), after a chemical etching with a 6.25M KOH solution, or with a 6.25M KOH solution with 20% methanol, both solutions at 60±1°C. As an example, the nitrogen ions deposit approximately 1 keV/nm in the form of ionization and excitation at the surface of PET, as calculated using the SRIM code. The fission fragments deposit up to 9 keV/nm at the surface, in both cases generating sufficient free radicals to initiate the track formation process. However, 5 MeV alpha particles, typical of radon (222Rn) emissions, deposit only 0.12 keV/nm, do not present tracks after the chemical etching process. This valuable information could be very useful for further studies of new materials in nuclear track methodology.

The status of the AMS system at MALT in its 20th year

NASA Astrophysics Data System (ADS)

Matsuzaki, Hiroyuki; Nakano, Chuichiro; Tsuchiya, Yoko S.; Ito, Seiji; Morita, Akira; Kusuno, Haruka; Miyake, Yasuto; Honda, Maki; Bautista VII, Angel T.; Kawamoto, Marina; Tokuyama, Hironori

2015-10-01

MALT (Micro Analysis Laboratory, Tandem accelerator, The University of Tokyo) was designed for a 'highly sensitive and precise elemental and isotopic microanalysis system' using an ion-beam generated by a Pelletron™ 5UD tandem accelerator. Currently, a multi-nuclide AMS (10Be, 14C, 26Al, 36Cl, 129I) system is available and shows good performance in both precision and sensitivity, and the accelerator serves for PIXE, NRA, ERDA/RBS measurements as well. The total operation time of the accelerator has been over 95,000 hours since the start of MALT, 20 years ago. After the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, many projects related to 129I have been conducted. The retrospective reconstruction of the 131I distribution at the accident from 129I is one of the most important missions for dose evaluation of the residents. The accident-derived 129I is also quite useful as a tracer for the general iodine dynamics in the environment. As a new tool for environmental assessment related to nuclear activity, including the global fallout from past atmospheric nuclear bomb testing, effects from the spent fuel reprocessing plant, and nuclear accidents such as Chernobyl and FDNPP, a 236U-AMS system is now under development.

Felsenkeller 5 MV underground accelerator: Towards the Holy Grail of Nuclear Astrophysics 12C(α, γ)16O

NASA Astrophysics Data System (ADS)

Bemmerer, Daniel; Cowan, Thomas E.; Grieger, Marcel; Hammer, Sebastian; Hensel, Thomas; Junghans, Arnd R.; Koppitz, Martina; Ludwig, Felix; Müller, Stefan E.; Rimarzig, Bernd; Reinicke, Stefan; Schwengner, Ronald; Stöckel, Klaus; Szücs, Tamás; Takács, Marcell P.; Turkat, Steffen; Wagner, Andreas; Wagner, Louis; Zuber, Kai

2018-05-01

Low-background experiments with stable ion beams are an important tool for putting the model of stellar hydrogen, helium, and carbon burning on a solid experimental foundation. The pioneering work in this regard has been done by the LUNA collaboration at Gran Sasso, using a 0.4 MV accelerator. The present contribution reviews the status of the project for a higher-energy underground accelerator in Felsenkeller, Germany. Results from γ-ray, neutron, and muon background measurements in the Felsenkeller underground site in Dresden, Germany, show that the background conditions are satisfactory. Two tunnels of the Felsenkeller site have recently been refurbished for the installation of a 5MV high-current Pelletron accelerator. Civil construction work has completed in March 2018. The accelerator will provide intense, 50 μA, beams of 1H+, 4He+, and 12C+ ions, enabling research on astrophysically relevant nuclear reactions with unprecedented sensitivity.

Heavy ion linear accelerator for radiation damage studies of materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kutsaev, Sergey V.; Mustapha, Brahim; Ostroumov, Peter N.

A new eXtreme MATerial (XMAT) research facility is being proposed at Argonne National Laboratory to enable rapid in situ mesoscale bulk analysis of ion radiation damage in advanced materials and nuclear fuels. This facility combines a new heavy-ion accelerator with the existing high-energy X-ray analysis capability of the Argonne Advanced Photon Source. The heavy-ion accelerator and target complex will enable experimenters to emulate the environment of a nuclear reactor making possible the study of fission fragment damage in materials. Material scientists will be able to use the measured material parameters to validate computer simulation codes and extrapolate the response ofmore » the material in a nuclear reactor environment. Utilizing a new heavy-ion accelerator will provide the appropriate energies and intensities to study these effects with beam intensities which allow experiments to run over hours or days instead of years. The XMAT facility will use a CW heavy-ion accelerator capable of providing beams of any stable isotope with adjustable energy up to 1.2 MeV/u for U-238(50+) and 1.7 MeV for protons. This energy is crucial to the design since it well mimics fission fragments that provide the major portion of the damage in nuclear fuels. The energy also allows damage to be created far from the surface of the material allowing bulk radiation damage effects to be investigated. The XMAT ion linac includes an electron cyclotron resonance ion source, a normal-conducting radio-frequency quadrupole and four normal-conducting multi-gap quarter-wave resonators operating at 60.625 MHz. This paper presents the 3D multi-physics design and analysis of the accelerating structures and beam dynamics studies of the linac.« less

Heavy ion linear accelerator for radiation damage studies of materials

NASA Astrophysics Data System (ADS)

Kutsaev, Sergey V.; Mustapha, Brahim; Ostroumov, Peter N.; Nolen, Jerry; Barcikowski, Albert; Pellin, Michael; Yacout, Abdellatif

2017-03-01

A new eXtreme MATerial (XMAT) research facility is being proposed at Argonne National Laboratory to enable rapid in situ mesoscale bulk analysis of ion radiation damage in advanced materials and nuclear fuels. This facility combines a new heavy-ion accelerator with the existing high-energy X-ray analysis capability of the Argonne Advanced Photon Source. The heavy-ion accelerator and target complex will enable experimenters to emulate the environment of a nuclear reactor making possible the study of fission fragment damage in materials. Material scientists will be able to use the measured material parameters to validate computer simulation codes and extrapolate the response of the material in a nuclear reactor environment. Utilizing a new heavy-ion accelerator will provide the appropriate energies and intensities to study these effects with beam intensities which allow experiments to run over hours or days instead of years. The XMAT facility will use a CW heavy-ion accelerator capable of providing beams of any stable isotope with adjustable energy up to 1.2 MeV/u for 238U50+ and 1.7 MeV for protons. This energy is crucial to the design since it well mimics fission fragments that provide the major portion of the damage in nuclear fuels. The energy also allows damage to be created far from the surface of the material allowing bulk radiation damage effects to be investigated. The XMAT ion linac includes an electron cyclotron resonance ion source, a normal-conducting radio-frequency quadrupole and four normal-conducting multi-gap quarter-wave resonators operating at 60.625 MHz. This paper presents the 3D multi-physics design and analysis of the accelerating structures and beam dynamics studies of the linac.

A SPACESHIP WITH NUCLEAR PROPULSION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polorny, J.

1962-01-01

ABS>A proposed space vehicle with nuclear propulsion for a round-trip Martian mission is described. It would be powered by a 270-Mw graphite- moderated, U-fueled nuclear reactor with a core 1 m high by 1 m in diameter, and use gas as propellant. The gas would be heated to the maximum temperature in the reactor and additionally accelerated by an electromagnetic field. To this end, small quantities of K would be injected into the gas stream to increase its electric conductivity. The required electrical energy would be produced by liquid-Na-cooled thermionic converters. The vehicle would weigh 115000 kg, including 43000 kgmore » of H propellant with tankage, and 7000 kg of sustenance material for one year. Chemical rockets would launch the vehicle with a crew of three men into an earth orbit where nuclear propulsion would take over. Upon reactor start-up, three heat exchangers (minimum dimensions 30 x 18 m) would be fanned out. A shielded well with a diameter of 2.5 m would protect the crew from radiation during reactor operation, passage through the earth radiation belts, and at periods of solar flares. (OTS)« less

From the Old to the New World of Nuclear Physics

NASA Astrophysics Data System (ADS)

Stuewer, Roger H.

Physicists passed from the Old to the New World of Nuclear Physics in the two decades between the first and second world wars. The transition occurred against the background of the Great War, the postwar hyperinflation in Germany and Austria, and the greatest intellection migrations in history after the Nazi Civil Service law of 1933, the Anschlussof Austria in March 1938, and the Fascist anti-Semitic laws that fall. It involved Rutherford's discovery of artificial disintegration, Pettersson and Kirsch's challenge of it, and the concomitant rise and fall of Rutherford's satellite model of the nucleus; Gamow's quantum-mechanical theory of alpha decay and his liquid-drop model of the nucleus; the discoveries of deuterium and the deuteron, neutron, and positron, and the inventions of the Cockcroft-Walton accelerator and the cyclotron; the influence of the seventh Solvay Conference; Joliot and Curie's discovery of artificial radioactivity; Pauli's neutrino hypothesis, Fermi's theory of beta decay, and his discovery of the efficacy of slow neutrons in producing nuclear reactions; Bohr's theory of the compound nucleus and Breit and Wigner's theory of neutron-nucleus resonances; and the discovery of nuclear fission, Meitner and Frisch's interpretation of it, and Bohr and Fermi revelation of both in America.

Advanced Compton scattering light source R&D at LLNL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Albert, F; Anderson, S G; Anderson, G

2010-02-16

We report the design and current status of a monoenergetic laser-based Compton scattering 0.5-2.5 MeV {gamma}-ray source. Previous nuclear resonance fluorescence results and future linac and laser developments for the source are presented. At MeV photon energies relevant for nuclear processes, Compton scattering light sources are attractive because of their relative compactness and improved brightness above 100 keV, compared to typical 4th generation synchrotrons. Recent progress in accelerator physics and laser technology have enabled the development of a new class of tunable Mono-Energetic Gamma-Ray (MEGa-Ray) light sources based on Compton scattering between a high-brightness, relativistic electron beam and a highmore » intensity laser pulse produced via chirped-pulse amplification (CPA). A new precision, tunable gamma-ray source driven by a compact, high-gradient X-band linac is currently under development and construction at LLNL. High-brightness, relativistic electron bunches produced by an X-band linac designed in collaboration with SLAC will interact with a Joule-class, 10 ps, diode-pumped CPA laser pulse to generate tunable {gamma}-rays in the 0.5-2.5 MeV photon energy range via Compton scattering. Based on the success of the previous Thomson-Radiated Extreme X-rays (T-REX) Compton scattering source at LLNL, the source will be used to excite nuclear resonance fluorescence lines in various isotopes; applications include homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. After a brief presentation of successful nuclear resonance fluorescence (NRF) experiments done with T-REX, the new source design, key parameters, and current status are presented.« less

Plastid–Nuclear Interaction and Accelerated Coevolution in Plastid Ribosomal Genes in Geraniaceae

PubMed Central

Weng, Mao-Lun; Ruhlman, Tracey A.; Jansen, Robert K.

2016-01-01

Plastids and mitochondria have many protein complexes that include subunits encoded by organelle and nuclear genomes. In animal cells, compensatory evolution between mitochondrial and nuclear-encoded subunits was identified and the high mitochondrial mutation rates were hypothesized to drive compensatory evolution in nuclear genomes. In plant cells, compensatory evolution between plastid and nucleus has rarely been investigated in a phylogenetic framework. To investigate plastid–nuclear coevolution, we focused on plastid ribosomal protein genes that are encoded by plastid and nuclear genomes from 27 Geraniales species. Substitution rates were compared for five sets of genes representing plastid- and nuclear-encoded ribosomal subunit proteins targeted to the cytosol or the plastid as well as nonribosomal protein controls. We found that nonsynonymous substitution rates (dN) and the ratios of nonsynonymous to synonymous substitution rates (ω) were accelerated in both plastid- (CpRP) and nuclear-encoded subunits (NuCpRP) of the plastid ribosome relative to control sequences. Our analyses revealed strong signals of cytonuclear coevolution between plastid- and nuclear-encoded subunits, in which nonsynonymous substitutions in CpRP and NuCpRP tend to occur along the same branches in the Geraniaceae phylogeny. This coevolution pattern cannot be explained by physical interaction between amino acid residues. The forces driving accelerated coevolution varied with cellular compartment of the sequence. Increased ω in CpRP was mainly due to intensified positive selection whereas increased ω in NuCpRP was caused by relaxed purifying selection. In addition, the many indels identified in plastid rRNA genes in Geraniaceae may have contributed to changes in plastid subunits. PMID:27190001

SHI induced nano track polymer filters and characterization

NASA Astrophysics Data System (ADS)

Vijay, Y. K.

2009-07-01

Swift heavy ion irradiation produces damage in polymers in the form of latent tracks. Latent tracks can be enlarged by etching it in a suitable etchant and thus nuclear track etch membrane can be formed for gas permeation / purification in particular for hydrogen where the molecular size is very small. By applying suitable and controlled etching conditions well defined tracks can be formed for specific applications of the membranes. After etching gas permeation method is used for characterizing the tracks. In the present work polycarbonate (PC) of various thickness were irradiated with energetic ion beam at Inter University Accelerator Centre (IUAC), New Delhi. Nuclear tracks were modified by etching the PC in 6N NaOH at 60 (±1) °C from both sides for different times to produce track etch membranes. At critical etch time the etched pits from both the sides meet a rapid increase in gas permeation was observed. Permeability of hydrogen and carbon dioxide has been measured in samples etched for different times. The latent tracks produced by SHI irradiation in the track etch membranes show enhancement of free volume of the polymer. Nano filters are separation devices for the mixture of gases, different ions in the solution and isotopes and isobars separations. The polymer thin films with controlled porosity finding it self as best choice. However, the permeability and selectivity of these polymer based membrane filters are very important at the nano scale separation. The Swift Heavy Ion (SHI) induced nuclear track etched polymeric films with controlled etching have been attempted and characterized as nano scale filters.

Transmutation of Isotopes --- Ecological and Energy Production Aspects

NASA Astrophysics Data System (ADS)

Gudowski, Waclaw

2000-01-01

This paper describes principles of Accelerator-Driven Transmutation of Nuclear Wastes (ATW) and gives some flavour of the most important topics which are today under investigations in many countries. An assessment of the potential impact of ATW on a future of nuclear energy is also given. Nuclear reactors based on self-sustained fission reactions --- after spectacular development in fifties and sixties, that resulted in deployment of over 400 power reactors --- are wrestling today more with public acceptance than with irresolvable technological problems. In a whole spectrum of reasons which resulted in today's opposition against nuclear power few of them are very relevant for the nuclear physics community and they arose from the fact that development of nuclear power had been handed over to the nuclear engineers and technicians with some generically unresolved problems, which should have been solved properly by nuclear scientists. In a certain degree of simplification one can say, that most of the problems originate from very specific features of a fission phenomenon: self-sustained chain reaction in fissile materials and very strong radioactivity of fission products and very long half-life of some of the fission and activation products. And just this enormous concentration of radioactive fission products in the reactor core is the main problem of managing nuclear reactors: it requires unconditional guarantee for the reactor core integrity in order to avoid radioactive contamination of the environment; it creates problems to handle decay heat in the reactor core and finally it makes handling and/or disposal of spent fuel almost a philosophical issue, due to unimaginable long time scales of radioactive decay of some isotopes. A lot can be done to improve the design of conventional nuclear reactors (like Light Water Reactors); new, better reactors can be designed but it seems today very improbable to expect any radical change in the public perception of conventional nuclear power. In this context a lot of hopes and expectations have been expressed for novel systems called Accelerator-Driven Systems, Accelerator-Driven Transmutation of Waste or just Hybrid Reactors. All these names are used for description of the same nuclear system combining a powerful particle accelerator with a subcritical reactor. A careful analysis of possible environmental impact of ATW together with limitation of this technology is presented also in this paper.

The Legnaro National Laboratories and the SPES facility: nuclear structure and reactions today and tomorrow

NASA Astrophysics Data System (ADS)

de Angelis, Giacomo; Fiorentini, Gianni

2016-11-01

There is a very long tradition of studying nuclear structure and reactions at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (Italian Institute of Nuclear Physics). The wide expertise acquired in building and running large germanium arrays has made the laboratories one of the most advanced research centers in γ-ray spectroscopy. The ’gamma group’ has been deeply involved in all the national and international developments of the last 20 years and is currently one of the major contributors to the AGATA project, the first (together with its American counterpart GRETINA) γ-detector array based on γ-ray tracking. This line of research is expected to be strongly boosted by the coming into operation of the SPES radioactive ion beam project, currently under construction at LNL. In this report, written on the occasion of the 40th anniversary of the Nobel prize awarded to Aage Bohr, Ben R Mottelson and Leo Rainwater and particularly focused on the physics of nuclear structure, we intend to summarize the different lines of research that have guided nuclear structure and reaction research at LNL in the last decades. The results achieved have paved the way for the present SPES facility, a new laboratories infrastructure producing and accelerating radioactive ion beams of fission fragments and other isotopes.

Accelerator-Based Studies of Heavy Ion Interactions Relevant to Space Biomedicine

NASA Technical Reports Server (NTRS)

Miller, J.; Heilbronn, L.; Zeitlin, C.

1999-01-01

Evaluation of the effects of space radiation on the crews of long duration space missions must take into account the interactions of high energy atomic nuclei in spacecraft and planetary habitat shielding and in the bodies of the astronauts. These heavy ions (i.e. heavier than hydrogen), while relatively small in number compared to the total galactic cosmic ray (GCR) charged particle flux, can produce disproportionately large effects by virtue of their high local energy deposition: a single traversal by a heavy charged particle can kill or, what may be worse, severely damage a cell. Research into the pertinent physics and biology of heavy ion interactions has consequently been assigned a high priority in a recent report by a task group of the National Research Council. Fragmentation of the incident heavy ions in shielding or in the human body will modify an initially well known radiation field and thereby complicate both spacecraft shielding design and the evaluation of potential radiation hazards. Since it is impractical to empirically test the radiation transport properties of each possible shielding material and configuration, a great deal of effort is going into the development of models of charged particle fragmentation and transport. Accurate nuclear fragmentation cross sections (probabilities), either in the form of measurements with thin targets or theoretical calculations, are needed for input to the transport models, and fluence measurements (numbers of fragments produced by interactions in thick targets) are needed both to validate the models and to test specific shielding materials and designs. Fluence data are also needed to characterize the incident radiation field in accelerator radiobiology experiments. For a number of years, nuclear fragmentation measurements at GCR-like energies have been carried out at heavy ion accelerators including the LBL Bevalac, Saturne (France), the Synchrophasotron and Nuklotron (Dubna, Russia), SIS-18 (GSI, Germany), the Alternating Gradient Synchrotron at Brookhaven National Laboratory (BNL AGS) and the Heavy Ion Medical Accelerator (HIMAC) in Chiba, Japan. Until fairly recently most of these experiments were done to investigate fundamental problems in nuclear physics, but with the increasing interest in heavy charged particles on the part of the space flight, radiobiology and radiotherapy communities, an increasing number of experiments are being directed at these areas. Some of these measurements are discussed in references therein. Over the past several years, our group has taken cross section and fluence data at the AGS and HIMAC for several incident beams with nuclear charge, Z, between 6 and 26 at energies between 290 and 1050 MeV/nucleon. Iron (Z = 26) has been studied most extensively, since it is the heaviest ion present in significant numbers in the GCR. Targets have included tissue-equivalent and proposed shielding materials, as well as a variety of elemental targets for cross section measurements. Most of the data were taken along the beam axis, but measurements have been made off-axis, as well. Here we present selected data and briefly discuss some implications for spacecraft and planetary habitat design.

LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Laser acceleration of neutrons (physical foundations)

NASA Astrophysics Data System (ADS)

Rivlin, Lev A.

2010-08-01

The concept of neutron acceleration in a gradient magnetic field of a 'drifting' standing electromagnetic wave is presented. The promising fields of application of an accelerated directional beam of ultracold neurons, in particular, remote initiation of nuclear reactions, are suggested.

Nonequilibrium Green's function theory for nonadiabatic effects in quantum electron transport

NASA Astrophysics Data System (ADS)

Kershaw, Vincent F.; Kosov, Daniel S.

2017-12-01

We develop nonequilibrium Green's function-based transport theory, which includes effects of nonadiabatic nuclear motion in the calculation of the electric current in molecular junctions. Our approach is based on the separation of slow and fast time scales in the equations of motion for Green's functions by means of the Wigner representation. Time derivatives with respect to central time serve as a small parameter in the perturbative expansion enabling the computation of nonadiabatic corrections to molecular Green's functions. Consequently, we produce a series of analytic expressions for non-adiabatic electronic Green's functions (up to the second order in the central time derivatives), which depend not solely on the instantaneous molecular geometry but likewise on nuclear velocities and accelerations. An extended formula for electric current is derived which accounts for the non-adiabatic corrections. This theory is concisely illustrated by the calculations on a model molecular junction.

Nonequilibrium Green's function theory for nonadiabatic effects in quantum electron transport.

PubMed

Kershaw, Vincent F; Kosov, Daniel S

2017-12-14

We develop nonequilibrium Green's function-based transport theory, which includes effects of nonadiabatic nuclear motion in the calculation of the electric current in molecular junctions. Our approach is based on the separation of slow and fast time scales in the equations of motion for Green's functions by means of the Wigner representation. Time derivatives with respect to central time serve as a small parameter in the perturbative expansion enabling the computation of nonadiabatic corrections to molecular Green's functions. Consequently, we produce a series of analytic expressions for non-adiabatic electronic Green's functions (up to the second order in the central time derivatives), which depend not solely on the instantaneous molecular geometry but likewise on nuclear velocities and accelerations. An extended formula for electric current is derived which accounts for the non-adiabatic corrections. This theory is concisely illustrated by the calculations on a model molecular junction.

Development of TPF-1 plasma focus for education

NASA Astrophysics Data System (ADS)

Picha, R.; Promping, J.; Channuie, J.; Poolyarat, N.; Sangaroon, S.; Traikool, T.

2017-09-01

The plasma focus is a device that uses high voltage and electromagnetic force to induce plasma generation and acceleration, in order to cause nuclear reactions. Radiation of various types (X-ray, gamma ray, electrons, ions, neutrons) can be generated using this method during the pinch phase, thus making the plasma focus able to serve as a radiation source. Material testing, modification, and identification are among the current applications of the plasma focus. Other than being an alternative option to isotopic sources, the plasma focus, which requires multidisciplinary team of personnel to design, operate, and troubleshoot, can also serve as an excellent learning device for physics and engineering students in the fields including, but not limited to, plasma physics, nuclear physics, electronics engineering, and mechanical engineering. This work describes the parameters and current status of Thai Plasma Focus 1 (TPF-1) and the characteristics of the plasma being produced in the machine using a Rogowski coil.

Mapping of the thermal neutron distribution in the lead block assembly of the PS-211 experiment at CERN, using thermoluminescence and nuclear track detectors.

PubMed

Savvidis, E; Eleftheriadis, C A; Kitis, G

2002-01-01

The main purpose of the TARC (Transmutation by Adiabatic Resonance Crossing) experiment (PS-211), was to demonstrate the possibility to destroy efficiently Long-Lived Fission Fragments (LLFF) in Accelerator Driven Systems (ADS). The experimental set-up which consisted of a lead block with dimensions 3.3 x 3.3 x 3 m3, was installed in a CERN Proton Synchrotron (PS) beam line. The proton beam at 2.5 GeV/c and 3.5 GeV/c, was incident in the centre of the lead block assembly producing neutrons via spallation reactions. In this study, neutron flux measurements are presented in the lead block assembly using thermoluminescence and nuclear track detectors. The results are in good agreement with Monte Carlo calculations as well as with the results of the other methods used in the framework of the TARC experiment.

Nuclear lamina defects cause ATM-dependent NF-κB activation and link accelerated aging to a systemic inflammatory response

PubMed Central

Osorio, Fernando G.; Bárcena, Clea; Soria-Valles, Clara; Ramsay, Andrew J.; de Carlos, Félix; Cobo, Juan; Fueyo, Antonio; Freije, José M.P.; López-Otín, Carlos

2012-01-01

Alterations in the architecture and dynamics of the nuclear lamina have a causal role in normal and accelerated aging through both cell-autonomous and systemic mechanisms. However, the precise nature of the molecular cues involved in this process remains incompletely defined. Here we report that the accumulation of prelamin A isoforms at the nuclear lamina triggers an ATM- and NEMO-dependent signaling pathway that leads to NF-κB activation and secretion of high levels of proinflammatory cytokines in two different mouse models of accelerated aging (Zmpste24−/− and LmnaG609G/G609G mice). Causal involvement of NF-κB in accelerated aging was demonstrated by the fact that both genetic and pharmacological inhibition of NF-κB signaling prevents age-associated features in these animal models, significantly extending their longevity. Our findings provide in vivo proof of principle for the feasibility of pharmacological modulation of the NF-κB pathway to slow down the progression of physiological and pathological aging. PMID:23019125

Nb3Sn SRF Cavities for Nuclear Physics Applications

NASA Astrophysics Data System (ADS)

Eremeev, Grigory

2017-01-01

Nuclear physics experiments rely increasingly on accelerators, which employ superconducting RF (SRF) technology. CEBAF, SNS, FRIB, ESS, among others exploit the low surface resistance of SRF cavities to efficiently accelerate particle beams towards experimental targets. Niobium is the cavity material of choice for all current or planned SRF accelerators, but it has been long recognized that other superconductors with high superconducting transition temperatures have the potential to surpass niobium for SRF applications. Among the alternatives, Nb3Sn coated cavities are the most advanced on the path to practical applications: Nb3Sn coatings on R&D cavities have Tc consistently close the optimal 18 K, very low RF surface resistances, and very recently were shown to reach above Hc1 without anomalous RF surface resistance increase. In my talk I will discuss the prospects of Nb3Sn SRF cavities, the research efforts to realize Nb3Sn coatings on practical multi-cell accelerating structures, and the path toward possible inclusion in CEBAF. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics.

Direct current H- source for the medicine accelerator (invited)

NASA Astrophysics Data System (ADS)

Belchenko, Yu.; Savkin, V.

2004-05-01

A compact cw hydrogen negative ion source having reliable operation and a simplified maintenance is developed at Budker Institute of Nuclear Physics for a tandem accelerator of boron capture neutron therapy installation. The source uses a Penning discharge with a hydrogen and cesium feed through the hollows in the cathodes. Discharge voltage is about 60-80 V, current 9 A, hydrogen pressure 4-5 Pa, magnetic field 0.05-0.1 T, and cesium seed <1 mg/h. Negative ions are mainly produced on the cesiated anode surface due to conversion of hydrogen atoms. An optimal anode temperature is 250-350 °C. Negative ion beam current is directly proportional to the discharge current and to the emission hole area. A triode system for the beam extraction and acceleration system is used. The flux of accompanying extracted electrons was decreased by filtering in the transverse magnetic field. This electron flux was intercepted to the special electrode, biased at 4 kV potential with respect to the anode. Source stable cw operation for several hour runs was multiply tested. A H- ion beam with current up to 8 mA, beam energy 23 keV was produced regularly. Negative ion current of heavy impurities had a value of about 3% of the total beam current. Beam normalized emittance is about 0.3 π mm mrad and emission current density -0.1 A/cm2. A built-in cathode heater provides the operation quick start.

Papers arising from IAEA Coordinated Research Project "Utilization of ion accelerators for studying and modelling of radiation induced defects in semiconductors and insulators" (F11016)

NASA Astrophysics Data System (ADS)

Vittone, Ettore; Breese, Mark; Simon, Aliz

2016-04-01

Within the International Atomic Energy Agency (IAEA) Department of Nuclear Sciences and Applications, activities are carried out to assist and advise IAEA Member States in assessing their needs for capacity building, research and development in nuclear sciences. Support is also provided to Member States' activities geared towards deriving benefits in fields such as (i) advanced materials for nuclear applications, (ii) application of accelerators and associated instrumentation, and (iii) nuclear, atomic and molecular data. One of the means that the IAEA uses to deliver its programme is Coordinated Research Projects (CRPs) which are very effective in stimulating international research and scientific interaction among the Member States.

Nuclear data for medical applications: An overview of present status and future needs

NASA Astrophysics Data System (ADS)

Syed, M. Qaim

2017-09-01

A brief overview of nuclear data required for medical applications is given. The major emphasis is on radionuclides for internal applications, both for diagnosis and therapy. The status of the presently available data is discussed and some of the emerging needs are outlined. Most of the needs are associated with the development of non-standard positron emitters and novel therapeutic radionuclides. Some new developments in application of radionuclides, e.g. theranostic approach, multimode imaging, radionanoparticles, etc. are described and the related nuclear data needs are discussed. The possible use of newer irradiation technologies for medical radionuclide production, e.g. intermediate energy charged-particle accelerators, high-power electron accelerators for photon production, and spallation neutron sources, will place heavy demands on nuclear data.

Detection of shielded nuclear material in a cargo container

NASA Astrophysics Data System (ADS)

Jones, James L.; Norman, Daren R.; Haskell, Kevin J.; Sterbentz, James W.; Yoon, Woo Y.; Watson, Scott M.; Johnson, James T.; Zabriskie, John M.; Bennett, Brion D.; Watson, Richard W.; Moss, Cavin E.; Frank Harmon, J.

2006-06-01

The Idaho National Laboratory, along with Los Alamos National Laboratory and the Idaho State University's Idaho Accelerator Center, are developing electron accelerator-based, photonuclear inspection technologies for the detection of shielded nuclear material within air-, rail-, and especially, maritime-cargo transportation containers. This paper describes a developing prototypical cargo container inspection system utilizing the Pulsed Photonuclear Assessment (PPA) technology, incorporates interchangeable, well-defined, contraband shielding structures (i.e., "calibration" pallets) providing realistic detection data for induced radiation signatures from smuggled nuclear material, and provides various shielded nuclear material detection results. Using a 4.8-kg quantity of depleted uranium, neutron and gamma-ray detection responses are presented for well-defined shielded and unshielded configurations evaluated in a selected cargo container inspection configuration.

An ion beam facility based on a 3 MV tandetron accelerator in Sichuan University, China

NASA Astrophysics Data System (ADS)

Han, Jifeng; An, Zhu; Zheng, Gaoqun; Bai, Fan; Li, Zhihui; Wang, Peng; Liao, Xiaodong; Liu, Mantian; Chen, Shunli; Song, Mingjiang; Zhang, Jun

2018-03-01

A new ion beam facility based on a 3 MV tandetron accelerator system has been installed in Sichuan University, China. The facility was developed by High Voltage Engineering Europa and consists of three high-energy beam lines including the ion beam analysis, ion implantation and nuclear physics experiment end stations, respectively. The terminal voltage stability of the accelerator is better than ±30 V, and the brightness of the proton beam is approximately 5.06 A/rad2/m2/eV. The system demonstrates a great application potential in fields such as nuclear, material and environmental studies.

Preliminary Consideration of the ADS Research in China

NASA Astrophysics Data System (ADS)

Fang, Shouxian; Fu, Shinian

2002-08-01

Power supply is a key issue for China's further economic development. To meet the needs of our economic growth in the next century, the part of nuclear energy in the total newly increased power supply must become larger. However, the present nuclear power stations dominated by the PWR in the world are facing some troubles. Recently, a new concept, called ADS (Accelerator Driven Subcritical system), can avoid these troubles and it is recognized as a most prospective power system for fission energy. So during the early time of nuclear power development in our country, it is worthwhile to exploit this novel idea. In this paper, the ADS research program and a proposed verification facility are described. It consists of an 300MeV/3mA low energy accelerator, a swimming pool reactor and some basic research equipment. Beam physics, such as beam halo formation, in the intense-beam accelerator is also discussed.

Measurement and Estimation of the 99Mo Production Yield by 100Mo(n,2n)99Mo

NASA Astrophysics Data System (ADS)

Minato, Futoshi; Tsukada, Kazuaki; Sato, Nozomi; Watanabe, Satoshi; Saeki, Hideya; Kawabata, Masako; Hashimoto, Shintaro; Nagai, Yasuki

2017-11-01

We, for the first time, measured the yield of 99Mo, the mother nuclide of 99mTc used in nuclear medicine diagnostic procedures, produced by the 100Mo(n,2n)99Mo reaction with accelerator neutrons. The neutrons with a continuous energy spectrum from the thermal energy up to about 40 MeV were provided by the C(d,n) reaction with 40 MeV deuteron beams. It was proved that the 99Mo yield agrees with that estimated by using the latest data on neutrons from the C(d,n) reaction and the evaluated cross section of the 100Mo(n,2n)99Mo reaction given in the Japanese Evaluated Nuclear Data Library. On the basis of the agreement, a systematic calculation was carried out to search for an optimum condition that enables us to produce as much 99Mo as possible with a good 99Mo/100Mo value from an economical point of view. The calculated 99Mo yield from a 150 g 100MoO3 sample indicated that about 30% of the demand for 99Mo in Japan can be met with a single accelerator capable of 40 MeV, 2 mA deuteron beams. Here, by referring to an existing 18F-fluorodeoxyglucose (FDG) distribution system we assumed that 99mTc radiopharmaceuticals formed after separating 99mTc from 99Mo can be delivered to hospitals from a radiopharmaceutical company within 6 h. The elution of 99mTc from 99Mo twice a day would meet about 50% of the demand for 99Mo.

Boron Neutron Capture Therapy for Malignant Brain Tumors

PubMed Central

MIYATAKE, Shin-Ichi; KAWABATA, Shinji; HIRAMATSU, Ryo; KUROIWA, Toshihiko; SUZUKI, Minoru; KONDO, Natsuko; ONO, Koji

2016-01-01

Boron neutron capture therapy (BNCT) is a biochemically targeted radiotherapy based on the nuclear capture and fission reactions that occur when non-radioactive boron-10, which is a constituent of natural elemental boron, is irradiated with low energy thermal neutrons to yield high linear energy transfer alpha particles and recoiling lithium-7 nuclei. Therefore, BNCT enables the application of a high dose of particle radiation selectively to tumor cells in which boron-10 compound has been accumulated. We applied BNCT using nuclear reactors for 167 cases of malignant brain tumors, including recurrent malignant gliomas, newly diagnosed malignant gliomas, and recurrent high-grade meningiomas from January 2002 to May 2014. Here, we review the principle and history of BNCT. In addition, we introduce fluoride-18-labeled boronophenylalanine positron emission tomography and the clinical results of BNCT for the above-mentioned malignant brain tumors. Finally, we discuss the recent development of accelerators producing epithermal neutron beams. This development could provide an alternative to the current use of specially modified nuclear reactors as a neutron source, and could allow BNCT to be performed in a hospital setting. PMID:27250576

Boron Neutron Capture Therapy for Malignant Brain Tumors.

PubMed

Miyatake, Shin-Ichi; Kawabata, Shinji; Hiramatsu, Ryo; Kuroiwa, Toshihiko; Suzuki, Minoru; Kondo, Natsuko; Ono, Koji

2016-07-15

Boron neutron capture therapy (BNCT) is a biochemically targeted radiotherapy based on the nuclear capture and fission reactions that occur when non-radioactive boron-10, which is a constituent of natural elemental boron, is irradiated with low energy thermal neutrons to yield high linear energy transfer alpha particles and recoiling lithium-7 nuclei. Therefore, BNCT enables the application of a high dose of particle radiation selectively to tumor cells in which boron-10 compound has been accumulated. We applied BNCT using nuclear reactors for 167 cases of malignant brain tumors, including recurrent malignant gliomas, newly diagnosed malignant gliomas, and recurrent high-grade meningiomas from January 2002 to May 2014. Here, we review the principle and history of BNCT. In addition, we introduce fluoride-18-labeled boronophenylalanine positron emission tomography and the clinical results of BNCT for the above-mentioned malignant brain tumors. Finally, we discuss the recent development of accelerators producing epithermal neutron beams. This development could provide an alternative to the current use of specially modified nuclear reactors as a neutron source, and could allow BNCT to be performed in a hospital setting.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Yuanbin; Pálffy, Adriana, E-mail: yuanbin.wu@mpi-hd.mpg.de, E-mail: Palffy@mpi-hd.mpg.de

Due to screening effects, nuclear reactions in astrophysical plasmas may behave differently than in the laboratory. The possibility to determine the magnitude of these screening effects in colliding laser-generated plasmas is investigated theoretically, having as a starting point a proposed experimental setup with two laser beams at the Extreme Light Infrastructure facility. A laser pulse interacting with a solid target produces a plasma through the Target Normal Sheath Acceleration scheme, and this rapidly streaming plasma (ion flow) impacts a secondary plasma created by the interaction of a second laser pulse on a gas jet target. We model this scenario heremore » and calculate the reaction events for the astrophysically relevant reaction {sup 13}C({sup 4}He, n ){sup 16}O. We find that it should be experimentally possible to determine the plasma screening enhancement factor for fusion reactions by detecting the difference in reaction events between two scenarios of ion flow interacting with the plasma target and a simple gas target. This provides a way to evaluate nuclear reaction cross-sections in stellar environments and can significantly advance the field of nuclear astrophysics.« less

Determination of Plasma Screening Effects for Thermonuclear Reactions in Laser-generated Plasmas

NASA Astrophysics Data System (ADS)

Wu, Yuanbin; Pálffy, Adriana

2017-03-01

Due to screening effects, nuclear reactions in astrophysical plasmas may behave differently than in the laboratory. The possibility to determine the magnitude of these screening effects in colliding laser-generated plasmas is investigated theoretically, having as a starting point a proposed experimental setup with two laser beams at the Extreme Light Infrastructure facility. A laser pulse interacting with a solid target produces a plasma through the Target Normal Sheath Acceleration scheme, and this rapidly streaming plasma (ion flow) impacts a secondary plasma created by the interaction of a second laser pulse on a gas jet target. We model this scenario here and calculate the reaction events for the astrophysically relevant reaction 13C(4He, n)16O. We find that it should be experimentally possible to determine the plasma screening enhancement factor for fusion reactions by detecting the difference in reaction events between two scenarios of ion flow interacting with the plasma target and a simple gas target. This provides a way to evaluate nuclear reaction cross-sections in stellar environments and can significantly advance the field of nuclear astrophysics.

From laser particle acceleration to the synthesis of extremely neutron rich isotopes via the novel fission-fusion mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thirolf, P. G., E-mail: Peter.Thirolf@lmu.de

2015-02-24

High-power, short pulse lasers have emerged in the last decade as attractive tools for accelerating charged particles (electrons, ions) to high energies over mm-scale acceleration lengths, thus promising to rival conventional acceleration techniques in the years ahead. In the first part of the article, the principles of laser-plasma interaction as well as the techniques and the current status of the acceleration of electron and ion beams will be briefly introduced. In particular with the upcoming next generation of multi-PW class laser systems, such as the one under construction for the ELI-Nuclear Physics project in Bucharest (ELI-NP), very efficient acceleration mechanismsmore » for brilliant ion beams like radiation pressure acceleration (RPA) come into reach. Here, ultra-dense ion beams reaching solid-state density can be accelerated from thin target foils, exceeding the density of conventionally accelerated ion beams by about 14 orders of magnitude. This unique property of laser-accelerated ion beams can be exploited to explore the scenario of a new reaction mechanism called ‘fission-fusion’, which will be introduced in the second part of the article. Accelerating fissile species (e.g. {sup 232}Th) towards a second layer of the same material will lead to fission both of the beam-like and target-like particles. Due to the close to solid-state density of the accelerated ion bunches, fusion may occur between neutron-rich (light) fission products. This may open an access path towards extremely neutron-rich nuclides in the vicinity of the N=126 waiting point of the astrophysical r process. ‘Waiting points’ at closed nucleon shells play a crucial role in controlling the reaction rates. However, since most of the pathway of heavy-element formation via the rapid-neutron capture process (r-process) runs in ‘terra incognita’ of the nuclear landscape, in particular the waiting point at N=126 is yet unexplored and will remain largely inaccessible to conventional nuclear reaction schemes even at next-generation radioactive beam facilities, underlining the attractive perspectives offered, e.g., by ELI-NP.« less

Accelerator Based Tools of Stockpile Stewardship

NASA Astrophysics Data System (ADS)

Seestrom, Susan

2017-01-01

The Manhattan Project had to solve difficult challenges in physics and materials science. During the cold war a large nuclear stockpile was developed. In both cases, the approach was largely empirical. Today that stockpile must be certified without nuclear testing, a task that becomes more difficult as the stockpile ages. I will discuss the role of modern accelerator based experiments, such as x-ray radiography, proton radiography, neutron and nuclear physics experiments, in stockpile stewardship. These new tools provide data of exceptional sensitivity and are answering questions about the stockpile, improving our scientific understanding, and providing validation for the computer simulations that are relied upon to certify todays' stockpile.

Plastid-Nuclear Interaction and Accelerated Coevolution in Plastid Ribosomal Genes in Geraniaceae.

PubMed

Weng, Mao-Lun; Ruhlman, Tracey A; Jansen, Robert K

2016-06-27

Plastids and mitochondria have many protein complexes that include subunits encoded by organelle and nuclear genomes. In animal cells, compensatory evolution between mitochondrial and nuclear-encoded subunits was identified and the high mitochondrial mutation rates were hypothesized to drive compensatory evolution in nuclear genomes. In plant cells, compensatory evolution between plastid and nucleus has rarely been investigated in a phylogenetic framework. To investigate plastid-nuclear coevolution, we focused on plastid ribosomal protein genes that are encoded by plastid and nuclear genomes from 27 Geraniales species. Substitution rates were compared for five sets of genes representing plastid- and nuclear-encoded ribosomal subunit proteins targeted to the cytosol or the plastid as well as nonribosomal protein controls. We found that nonsynonymous substitution rates (dN) and the ratios of nonsynonymous to synonymous substitution rates (ω) were accelerated in both plastid- (CpRP) and nuclear-encoded subunits (NuCpRP) of the plastid ribosome relative to control sequences. Our analyses revealed strong signals of cytonuclear coevolution between plastid- and nuclear-encoded subunits, in which nonsynonymous substitutions in CpRP and NuCpRP tend to occur along the same branches in the Geraniaceae phylogeny. This coevolution pattern cannot be explained by physical interaction between amino acid residues. The forces driving accelerated coevolution varied with cellular compartment of the sequence. Increased ω in CpRP was mainly due to intensified positive selection whereas increased ω in NuCpRP was caused by relaxed purifying selection. In addition, the many indels identified in plastid rRNA genes in Geraniaceae may have contributed to changes in plastid subunits. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Recent measurements for hadrontherapy and space radiation: nuclear physics

NASA Technical Reports Server (NTRS)

Miller, J.

2001-01-01

The particles and energies commonly used for hadron therapy overlap the low end of the charge and energy range of greatest interest for space radiation applications, Z=1-26 and approximately 100-1000 MeV/nucleon. It has been known for some time that the nuclear interactions of the incident ions must be taken into account both in treatment planning and in understanding and addressing the effects of galactic cosmic ray ions on humans in space. Until relatively recently, most of the studies of nuclear fragmentation and transport in matter were driven by the interests of the nuclear physics and later, the hadron therapy communities. However, the experimental and theoretical methods and the accelerator facilities developed for use in heavy ion nuclear physics are directly applicable to radiotherapy and space radiation studies. I will briefly review relevant data taken recently at various accelerators, and discuss the implications of the measurements for radiotherapy, radiobiology and space radiation research.

Tools for the Future of Nuclear Physics

NASA Astrophysics Data System (ADS)

Geesaman, Donald

2014-03-01

The challenges of Nuclear Physics, especially in understanding strongly interacting matter in all its forms in the history of the universe, place ever higher demands on the tools of the field, including the workhorse, accelerators. These demands are not just higher energy and higher luminosity. To recreate the matter that fleetingly was formed in the origin of the heavy elements, we need higher power heavy-ion accelerators and creative techniques to harvest the isotopes. We also need high-current low-energy accelerators deep underground to detect the very slow rate reactions in stellar burning. To explore the three dimensional distributions of high-momentum quarks in hadrons and to search for gluonic excitations we need high-current CW electron accelerators. Understanding the gluonic structure of nuclei and the three dimensional distributions of partons at lower x, we need high-luminosity electron-ion colliders that also have the capabilities to prepare, preserve and manipulate the polarization of both beams. A search for the critical point in the QCD phase diagram demands high luminosity beams over a broad range of species and energy. With advances in cavity design and construction, beam manipulation and cooling, and ion sources and targets, the Nuclear Physics community, in the U.S. and internationally has a coordinated vision to deliver this exciting science. This work is supported by DOE, Office of Nuclear Physics, under contract DE-AC02-06CH11357.

The Dresden Felsenkeller shallow-underground accelerator laboratory for nuclear astrophysics - Status and first physics program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ilgner, Ch.

Favored by the low background in underground laboratories, low-background accelerator-based experiments are an important tool to study nuclear reactions involving stable charged particles. This technique has been used for many years with great success at the 0.4 MV LUNA accelerator in the Gran Sasso laboratory in Italy, protected from cosmic rays by 1400 m of rock. However, the nuclear reactions of helium and carbon burning and the neutron source reactions for the astrophysical s-process require higher beam energies than those available at LUNA. Also the study of solar fusion reactions necessitates new data at higher energies. As a result, inmore » the present NuPECC long range plan for nuclear physics in Europe, the installation of one or more higher-energy underground accelerators is strongly recommended. An intercomparison exercise using the same High-Purity Ge detector at several sites has shown that, with a combination of 45 m rock overburden, as can be found in the Felsenkeller underground site in Dresden, and an active veto against the remaining muon flux, in a typical nuclear astrophysics setup a background level can be achieved that is similar to the deep underground scenario as in the Gran- Sasso underground laboratory, for instance. Recently, a muon background study and geodetic measurements were carried out by the REGARD group. It was estimated that the rock overburden at the place of the future ion accelerator is equivalent to 130 m of water. The maximum muon flux measured was 2.5 m{sup -2} sr{sup -1} s{sup -1}, in the direction of the tunnel entrance. Based on this finding, a used 5 MV pelletron tandem accelerator with 250 μA up-charge current and external sputter ion source has been obtained and transported to Dresden. Work on an additional radio-frequency ion source on the high voltage terminal is in progress and far advanced. The installation of the accelerator in the Felsenkeller is expected for the near future. The status of the project and the planned access possibilities for external users will be reported, together with the instrumentation to be installed and proposals for the first solar physics measurements to be done at this new low-background facility. (authors)« less

Nuclear tracks in CR-39 produced by carbon, oxygen, aluminium and titanium ions.

PubMed

Rickards, J; Romo, V; Golzarri, J I; Espinosa, G

2002-01-01

This work describes the response of CR-39 (allyl diglycol polycarbonate) to different ions (C, O, Al and Ti) produced by the Instituto de Fisica 3 MV 9SDH-2 Pelletron accelerator and backscattered from a thin Au film on a C support. The ion energies were chosen in series such that the ranges of the different ions in the detector were 2, 3, 4, 5, 6, 7 and 8 microm respectively for each series. Once exposed, the detectors were etched with a solution of 6.25 M KOH at 60 degrees C, and the reading was carried out using a digital image analysis system. An analysis of the measured track diameters of all the types of ions indicates that, for a given range, track kinetics are independent of type of ion, energy and stopping power.

Fluctuation analysis of relativistic nucleus-nucleus collisions in emulsion chambers

NASA Technical Reports Server (NTRS)

Mcguire, Stephen C.

1988-01-01

An analytical technique was developed for identifying enhanced fluctuations in the angular distributions of secondary particles produced from relativistic nucleus-nucleus collisions. The method is applied under the assumption that the masses of the produced particles are small compared to their linear momenta. The importance of particles rests in the fact that enhanced fluctuations in the rapidity distributions is considered to be an experimental signal for the creation of the quark-gluon-plasma (QGP), a state of nuclear matter predicted from the quantum chromodynamics theory (QCD). In the approach, Monte Carlo simulations are employed that make use of a portable random member generator that allow the calculations to be performed on a desk-top computer. The method is illustrated with data taken from high altitude emulsion exposures and is immediately applicable to similar data from accelerator-based emulsion exposures.

Measurements of Short-Lived Fission Isomers

NASA Astrophysics Data System (ADS)

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.

Beyond prometheus and Bakasura: Elements of an alternative to nuclear power in India's response to the energy-environment crisis

NASA Astrophysics Data System (ADS)

Mathai, Manu Verghese

In India, as elsewhere, modern energy-society relations and economic development, metaphorically, Prometheus and the insatiable demon Bakasura, respectively, have produced unprecedented economic growth even as they have ushered in the "energy-environment crisis." Government efforts interpret the crisis as insufficiently advanced modernity. Resulting efforts to redress this crisis reaffirm more economic growth through modern energy-society relations and economic development. The civilian nuclear power renaissance in India, amidst rapidly accelerating economic growth and global climate change, is indicative. It presents the prospect of producing "abundant energy" and being "green" at the same time. This confidence in civilian nuclear power is questioned. It is investigated as proceeding from the modern discourse of "Cornucopianism" and its institutionalization as "modern megamachine organization of society." It is found that civilian nuclear power as energy policy is based on a presumption of overabundance as imperative for viable social and economic development; is predisposed to centralization and secrecy; its institutionalization limits deliberation on energy-society relations to technocratic terms; such deliberation is restrained to venues accessible only to the highest political office and technocratic elite; it fails to redress entrenched "energy injustice;" it embodies "modern technique" fostering the "displaced person" while eclipsing the "complete human personality." Overall, despite its green rhetoric, civilian nuclear power reaffirms the "politics of commodification" and refutes social and political arrangements for sustainability and equity. Alternatives are surveyed as strategies for resistance. They include the DEFENDUS approach for energy planning, the "Human Development and Capability Approach" and the "Sustainable Energy Utility." These alternatives and the synergy between them are offered as avenues to resist nuclear power as a response to the energy-environment crisis and to reclaim human-centered imagination and creativity for charting new realities free of the awe inspired by Prometheus and fear of the insatiable Bakasura.

EH 11n modes E type in the disk and washer accelerating structure

NASA Astrophysics Data System (ADS)

Andreev, V. G.; Belugin, V. M.; Daikovsky, A. G.; Esin, S. K.; Kravchuk, L. V.; Paramonov, V. V.; Ryabov, A. D.

1983-01-01

The disk and washer accelerating structure has a great deal to do with high-beta structures progress. The frequencies and electromagnetic fields for modes, which have a different number of azimuthal variations, are calculated to determined the dispersion properties and other characteristics of parasitic modes in a disc and washer accelerating structure. The main attention was given to the accelerating structure of the linear accelerator of the Institute for Nuclear Research (INR) of the USSR Academy of Sciences. Modification of a structure for PIGMI accelerator (LANL, USA) is considered briefly.

An overview of the facilities, activities, and developments at the University of North Texas Ion Beam Modification and Analysis Laboratory (IBMAL)

NASA Astrophysics Data System (ADS)

Rout, Bibhudutta; Dhoubhadel, Mangal S.; Poudel, Prakash R.; Kummari, Venkata C.; Pandey, Bimal; Deoli, Naresh T.; Lakshantha, Wickramaarachchige J.; Mulware, Stephen J.; Baxley, Jacob; Manuel, Jack E.; Pacheco, Jose L.; Szilasi, Szabolcs; Weathers, Duncan L.; Reinert, Tilo; Glass, Gary A.; Duggan, Jerry L.; McDaniel, Floyd D.

2013-07-01

The Ion Beam Modification and Analysis Laboratory (IBMAL) at the University of North Texas includes several accelerator facilities with capabilities of producing a variety of ion beams from tens of keV to several MeV in energy. The four accelerators are used for research, graduate and undergraduate education, and industrial applications. The NEC 3MV Pelletron tandem accelerator has three ion sources for negative ions: He Alphatross and two different SNICS-type sputter ion sources. Presently, the tandem accelerator has four high-energy beam transport lines and one low-energy beam transport line directly taken from the negative ion sources for different research experiments. For the low-energy beam line, the ion energy can be varied from ˜20 to 80 keV for ion implantation/modification of materials. The four post-acceleration beam lines include a heavy-ion nuclear microprobe; multi-purpose PIXE, RBS, ERD, NRA, and broad-beam single-event upset; high-energy ion implantation line; and trace-element accelerator mass spectrometry. The NEC 3MV single-ended Pelletron accelerator has an RF ion source mainly for hydrogen, helium and heavier inert gases. We recently installed a capacitive liner to the terminal potential stabilization system for high terminal voltage stability and high-resolution microprobe analysis. The accelerator serves a beam line for standard RBS and RBS/C. Another beamline for high energy focused ion beam application using a magnetic quadrupole lens system is currently under construction. This beam line will also serve for developmental work on an electrostatic lens system. The third accelerator is a 200 kV Cockcroft-Walton accelerator with an RF ion source. The fourth accelerator is a 2.5 MV Van de Graaff accelerator, which was in operation for last several decades is currently planned to be used mainly for educational purpose. Research projects that will be briefly discussed include materials synthesis/modification for photonic, electronic, and magnetic applications, surface sputtering and micro-fabrication of materials, development of high-energy ion microprobe systems, and educational and outreach activities.

An overview of the facilities, activities, and developments at the University of North Texas Ion Beam Modification and Analysis Laboratory (IBMAL)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rout, Bibhudutta; Dhoubhadel, Mangal S.; Poudel, Prakash R.

2013-07-03

The Ion Beam Modification and Analysis Laboratory (IBMAL) at the University of North Texas includes several accelerator facilities with capabilities of producing a variety of ion beams from tens of keV to several MeV in energy. The four accelerators are used for research, graduate and undergraduate education, and industrial applications. The NEC 3MV Pelletron tandem accelerator has three ion sources for negative ions: He Alphatross and two different SNICS-type sputter ion sources. Presently, the tandem accelerator has four high-energy beam transport lines and one low-energy beam transport line directly taken from the negative ion sources for different research experiments. Formore » the low-energy beam line, the ion energy can be varied from {approx}20 to 80 keV for ion implantation/modification of materials. The four post-acceleration beam lines include a heavy-ion nuclear microprobe; multi-purpose PIXE, RBS, ERD, NRA, and broad-beam single-event upset; high-energy ion implantation line; and trace-element accelerator mass spectrometry. The NEC 3MV single-ended Pelletron accelerator has an RF ion source mainly for hydrogen, helium and heavier inert gases. We recently installed a capacitive liner to the terminal potential stabilization system for high terminal voltage stability and high-resolution microprobe analysis. The accelerator serves a beam line for standard RBS and RBS/C. Another beamline for high energy focused ion beam application using a magnetic quadrupole lens system is currently under construction. This beam line will also serve for developmental work on an electrostatic lens system. The third accelerator is a 200 kV Cockcroft-Walton accelerator with an RF ion source. The fourth accelerator is a 2.5 MV Van de Graaff accelerator, which was in operation for last several decades is currently planned to be used mainly for educational purpose. Research projects that will be briefly discussed include materials synthesis/modification for photonic, electronic, and magnetic applications, surface sputtering and micro-fabrication of materials, development of high-energy ion microprobe systems, and educational and outreach activities.« less

Laser driven nuclear science and applications: The need of high efficiency, high power and high repetition rate Laser beams

NASA Astrophysics Data System (ADS)

Gales, S.

2015-10-01

Extreme Light Infrastructure (ELI) is a pan European research initiative selected on the European Strategy Forum on Research Infrastructures Roadmap that aims to close the gap between the existing laboratory-based laser driven research and international facility-grade research centre. The ELI-NP facility, one of the three ELI pillars under construction, placed in Romania and to be operational in 2018, has as core elements a couple of new generation 10 PW laser systems and a narrow bandwidth Compton backscattering gamma source with photon energies up to 19 MeV. ELI-NP will address nuclear photonics, nuclear astrophysics and quantum electrodynamics involving extreme photon fields. Prospective applications of high power laser in nuclear astrophysics, accelerator physics, in particular towards future Accelerator Driven System, as well as in nuclear photonics, for detection and characterization of nuclear material, and for nuclear medicine, will be discussed. Key issues in these research areas will be at reach with significant increase of the repetition rates and of the efficiency at the plug of the high power laser systems as proposed by the ICAN collaboration.

Development of the Accelerator Mass Spectrometry technology at the Comenius University in Bratislava

NASA Astrophysics Data System (ADS)

Povinec, Pavel P.; Masarik, Jozef; Ješkovský, Miroslav; Kaizer, Jakub; Šivo, Alexander; Breier, Robert; Pánik, Ján; Staníček, Jaroslav; Richtáriková, Marta; Zahoran, Miroslav; Zeman, Jakub

2015-10-01

An Accelerator Mass Spectrometry (AMS) laboratory has been established at the Centre for Nuclear and Accelerator Technologies (CENTA) at the Comenius University in Bratislava comprising of a MC-SNICS ion source, 3 MV Pelletron tandem accelerator, and an analyzer of accelerated ions. The preparation of targets for 14C and 129I AMS measurements is described in detail. The development of AMS techniques for potassium, uranium and thorium analysis in radiopure materials required for ultra-low background underground experiments is briefly mentioned.

Recent optimization of the beam-optical characteristics of the 6 MV van de Graaff accelerator for high brightness beams at the iThemba LABS NMP facility

NASA Astrophysics Data System (ADS)

Conradie, J. L.; Eisa, M. E. M.; Celliers, P. J.; Delsink, J. L. G.; Fourie, D. T.; de Villiers, J. G.; Maine, P. M.; Springhorn, K. A.; Pineda-Vargas, C. A.

2005-04-01

With the aim of improving the reliability and stability of the beams delivered to the nuclear microprobe at iThemba LABS, as well as optimization of the beam characteristics along the van de Graaff accelerator beamlines in general, relevant modifications were implemented since the beginning of 2003. The design and layout of the beamlines were revised. The beam-optical characteristics through the accelerator, from the ion source up to the analysing magnet directly after the accelerator, were calculated and the design optimised, using the computer codes TRANSPORT, IGUN and TOSCA. The ion source characteristics and optimal operating conditions were determined on an ion source test bench. The measured optimal emittance for 90% of the beam intensity was about 50π mm mrad for an extraction voltage of 6 kV. These changes allow operation of the Nuclear Microprobe at proton energies in the range 1 MeV-4 MeV with beam intensities of tenths of a pA at the target surface. The capabilities of the nuclear microprobe facility were evaluated in the improved beamline, with particular emphasis to bio-medical samples.

Underground Nuclear Astrophysics - from LUNA to CASPAR

NASA Astrophysics Data System (ADS)

Strieder, Frank; Caspar Collaboration

2015-04-01

It is in the nature of astrophysics that many of the processes and objects are physically inaccessible. Thus, it is important that those aspects that can be studied in the laboratory are well understood. Nuclear reactions are such quantities that can be partly measured in the laboratory. These reactions influence the nucleosynthesis of the elements in the Big Bang as well as in all objects formed thereafter, and control the associated energy generation and evolution of stars. Since 20 years LUNA (Laboratory for Underground Nuclear Astrophysics) has been measuring cross sections relevant for hydrogen burning in the Gran Sasso Laboratory and demonstrated the research potential of an underground accelerator facility. Unfortunately, the number of reactions is limited by the energy range accessible with the 400 kV LUNA accelerator. The CASPAR (Compact Accelerator System for Performing Astrophysical Research) Collaboration will implement a high intensity 1 MV accelerator at the Sanford Underground Research Facility (SURF) and overcome the current limitation at LUNA. This project will primarily focus on the neutron sources for the so-called s-process, e.g. 13 C(α , n) 16 O and 22 Ne(α , n) 25 Mg , and lead to unprecedented measurements compared to previous studies.

Directional Track Selection Technique in CR39 SSNTD for lowyield reaction experiments

NASA Astrophysics Data System (ADS)

Ingenito, Francesco; Andreoli, Pierluigi; Batani, Dimitri; Bonasera, Aldo; Boutoux, Guillaume; Burgy, Frederic; Cipriani, Mattia; Consoli, Fabrizio; Cristofari, Giuseppe; De Angelis, Riccardo; Di Giorgio, Giorgio; Ducret, Jean Eric; Giulietti, Danilo; Jakubowska, Katarzyna

2018-01-01

There is a great interest in the study of p-11B aneutronic nuclear fusion reactions, both for energy production and for determination of fusion cross-sections at low energies. In this context we performed experiments at CELIA in which energetic protons, accelerated by the laser ECLIPSE, were directed toward a solid Boron target. Because of the small cross-sections at these energies the number of expected reactions is low. CR39 Solid-State Nuclear Track Detectors (SSNTD) were used to detect the alpha particles produced. Because of the low expected yield, it is difficult to discriminate the tracks due to true fusion products from those due to natural background in the CR39. To this purpose we developed a methodology of particle recognition according to their direction with respect to the detector normal, able to determine the position of their source. We applied this to the specific experiment geometry, so to select from all the tracks those due to particles coming from the region of interaction between accelerated protons and solid boron target. This technique can be of great help on the analysis of SSNTD in experiments with low yield reactions, but can be also generally applied to any experiment where particles reach the track detector with known directions, and for example to improve the detection limit of particle spectrometers using CR39.

The new 6 MV AMS-facility DREAMS at Dresden

NASA Astrophysics Data System (ADS)

Akhmadaliev, Shavkat; Heller, René; Hanf, Daniel; Rugel, Georg; Merchel, Silke

2013-01-01

A new 6 MV electrostatic tandem accelerator has been put into operation at Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The system is equipped for accelerator mass spectrometry and opens a new research field at HZDR and the Helmholtz Association. It will be also used for ion beam analysis as well as for material modification via high-energy ion implantation. The research activity at the DREsden Accelerator Mass Spectrometry facility (DREAMS) based on a 6 MV Tandetron is primarily dedicated to the long-lived radioisotopes of 10Be, 26Al, 36Cl, 41Ca, and 129I. DREAMS background levels have been found to be at 4.5 × 10-16 for 10Be/9Be, 8 × 10-16 for 26Al/27Al, 3 × 10-15 for 36Cl/35Cl and 8 × 10-15 for 41Ca/40Ca, respectively. The observed background of 2 × 10-13 for 129I/127I originates from intrinsic 129I from AgI produced from commercial KI. The introduction of quality assurance approaches for AMS, such as the use of traceable calibration materials and taking part in interlaboratory comparisons, guarantees high accuracy data for future DREAMS users. During first experiments an energy calibration of the accelerator has been carried out using the nuclear reaction 1H(15N,γα)12C yielding an energy correction factor of 1.019.

Efficient acceleration of neutral atoms in laser produced plasma

DOE PAGES

Dalui, M.; Trivikram, T. M.; Colgan, James Patrick; ...

2017-06-20

Recent advances in high-intensity laser-produced plasmas have demonstrated their potential as compact charge particle accelerators. Unlike conventional accelerators, transient quasi-static charge separation acceleration fields in laser produced plasmas are highly localized and orders of magnitude larger. Manipulating these ion accelerators, to convert the fast ions to neutral atoms with little change in momentum, transform these to a bright source of MeV atoms. The emittance of the neutral atom beam would be similar to that expected for an ion beam. Since intense laser-produced plasmas have been demonstrated to produce high-brightness-low-emittance beams, it is possible to envisage generation of high-flux, low-emittance, highmore » energy neutral atom beams in length scales of less than a millimeter. Here, we show a scheme where more than 80% of the fast ions are reduced to energetic neutral atoms and demonstrate the feasibility of a high energy neutral atom accelerator that could significantly impact applications in neutral atom lithography and diagnostics.« less

Search for Light Dark Matter Produced in a Proton Beam Dump

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thornton, Remington Tyler

Cosmological observations indicate that our universe contains dark matter (DM), yet we have no measurements of its microscopic properties. Whereas the gravitational interaction of DM is well understood, its interaction with the Standard Model is not. Direct detection experiments, the current standard, search for a nuclear recoil interaction and have a low-mass sensitivity edge of order 1 GeV. A path to detect DM with mass below 1 GeV is the use of accelerators producing boosted low-mass DM. Using neutrino detectors to search for low-mass DM is logical due to the similarity of the DM and neutrino signatures in the detector.more » The MiniBooNE experiment, located at Fermilab on the Booster Neutrino Beamline, has produced the first proton beam-dump light DM search results. Using dark matter scattering from nucleons 90% confidence limits were set over a large parameter space and, to allow tests of other theories, a model independent DM rate was extracted.« less

Search for light dark matter produced in a proton beam dump

NASA Astrophysics Data System (ADS)

Thornton, Remington Tyler

Cosmological observations indicate that our universe contains dark matter (DM), yet we have no measurements of its microscopic properties. Whereas the gravitational interaction of DM is well understood, its interaction with the Standard Model is not. Direct detection experiments, the current standard, search for a nuclear recoil interaction and have a low-mass sensitivity edge of order 1 GeV. A path to detect DM with mass below 1 GeV is the use of accelerators producing boosted low-mass DM. Using neutrino detectors to search for low-mass DM is logical due to the similarity of the DM and neutrino signatures in the detector. The MiniBooNE experiment, located at Fermilab on the Booster Neutrino Beamline, has produced the first proton beam-dump light DM search results. Using dark matter scattering from nucleons 90% confidence limits were set over a large parameter space and, to allow tests of other theories, a model independent DM rate was extracted.

Mitochondrial-nuclear interactions and accelerated compensatory evolution: evidence from the primate cytochrome C oxidase complex.

PubMed

Osada, Naoki; Akashi, Hiroshi

2012-01-01

Accelerated rates of mitochondrial protein evolution have been proposed to reflect Darwinian coadaptation for efficient energy production for mammalian flight and brain activity. However, several features of mammalian mtDNA (absence of recombination, small effective population size, and high mutation rate) promote genome degradation through the accumulation of weakly deleterious mutations. Here, we present evidence for "compensatory" adaptive substitutions in nuclear DNA- (nDNA) encoded mitochondrial proteins to prevent fitness decline in primate mitochondrial protein complexes. We show that high mutation rate and small effective population size, key features of primate mitochondrial genomes, can accelerate compensatory adaptive evolution in nDNA-encoded genes. We combine phylogenetic information and the 3D structure of the cytochrome c oxidase (COX) complex to test for accelerated compensatory changes among interacting sites. Physical interactions among mtDNA- and nDNA-encoded components are critical in COX evolution; amino acids in close physical proximity in the 3D structure show a strong tendency for correlated evolution among lineages. Only nuclear-encoded components of COX show evidence for positive selection and adaptive nDNA-encoded changes tend to follow mtDNA-encoded amino acid changes at nearby sites in the 3D structure. This bias in the temporal order of substitutions supports compensatory weak selection as a major factor in accelerated primate COX evolution.

Calibration of imaging plate detectors to mono-energetic protons in the range 1-200 MeV

NASA Astrophysics Data System (ADS)

Rabhi, N.; Batani, D.; Boutoux, G.; Ducret, J.-E.; Jakubowska, K.; Lantuejoul-Thfoin, I.; Nauraye, C.; Patriarca, A.; Saïd, A.; Semsoum, A.; Serani, L.; Thomas, B.; Vauzour, B.

2017-11-01

Responses of Fuji Imaging Plates (IPs) to proton have been measured in the range 1-200 MeV. Mono-energetic protons were produced with the 15 MV ALTO-Tandem accelerator of the Institute of Nuclear Physics (Orsay, France) and, at higher energies, with the 200-MeV isochronous cyclotron of the Institut Curie—Centre de Protonthérapie d'Orsay (Orsay, France). The experimental setups are described and the measured photo-stimulated luminescence responses for MS, SR, and TR IPs are presented and compared to existing data. For the interpretation of the results, a sensitivity model based on the Monte Carlo GEANT4 code has been developed. It enables the calculation of the response functions in a large energy range, from 0.1 to 200 MeV. Finally, we show that our model reproduces accurately the response of more complex detectors, i.e., stack of high-Z filters and IPs, which could be of great interest for diagnostics of Petawatt laser accelerated particles.

Environmental 90Sr measurements

USGS Publications Warehouse

Paul, M.; Berkovits, D.; Cecil, L.D.; Feldstein, H.; Hershkowitz, A.; Kashiv, Y.; Vogt, S.

1997-01-01

90Sr (T1/2 = 28.5 years) is a long-lived radionuclide produced in nuclear fission. Fast radiochemical detection of 90Sr in environmental samples is not feasible using current analytical methods. Accelerator Mass Spectrometry (AMS) measurements of 90Sr were made with the Rehovot 14UD Pelletron accelerator at a terminal voltage of 11 or 12 MV using our standard detection system. Injection of hydride ions (SrH3-) was chosen owing to high beam intensity and low Coulomb explosion effects. 90Sr ions were identified and discriminated from isobaric 90Zr by measuring time of flight, total energy and three independent energy-loss signals in an ionization chamber. A reference sample and a ground-water sample were successfully measured. The detection limit determined for a laboratory blank by the residual counts in the 90Sr region is 90Sr/Sr = 3 ?? 10-13, corresponding in practice to (2-4) ?? 10790Sr atoms or about 0.5-1 pCi/L in environmental water samples.

Development and construction of a neutron beam line for accelerator-based boron neutron capture synovectomy.

PubMed

Gierga, D P; Yanch, J C; Shefer, R E

2000-01-01

A potential application of the 10B(n, alpha)7Li nuclear reaction for the treatment of rheumatoid arthritis, termed Boron Neutron Capture Synovectomy (BNCS), is under investigation. In an arthritic joint, the synovial lining becomes inflamed and is a source of great pain and discomfort for the afflicted patient. The goal of BNCS is to ablate the synovium, thereby eliminating the symptoms of the arthritis. A BNCS treatment would consist of an intra-articular injection of boron followed by neutron irradiation of the joint. Monte Carlo radiation transport calculations have been used to develop an accelerator-based epithermal neutron beam line for BNCS treatments. The model includes a moderator/reflector assembly, neutron producing target, target cooling system, and arthritic joint phantom. Single and parallel opposed beam irradiations have been modeled for the human knee, human finger, and rabbit knee joints. Additional reflectors, placed to the side and back of the joint, have been added to the model and have been shown to improve treatment times and skin doses by about a factor of 2. Several neutron-producing charged particle reactions have been examined for BNCS, including the 9Be(p,n) reaction at proton energies of 4 and 3.7 MeV, the 9Be(d,n) reaction at deuteron energies of 1.5 and 2.6 MeV, and the 7Li(p,n) reaction at a proton energy of 2.5 MeV. For an accelerator beam current of 1 mA and synovial boron uptake of 1000 ppm, the time to deliver a therapy dose of 10,000 RBEcGy ranges from 3 to 48 min, depending on the treated joint and the neutron producing charged particle reaction. The whole-body effective dose that a human would incur during a knee treatment has been estimated to be 3.6 rem or 0.75 rem, for 1000 ppm or 19,000 ppm synovial boron uptake, respectively, although the shielding configuration has not yet been optimized. The Monte Carlo design process culminated in the construction, installation, and testing of a dedicated BNCS beam line on the high-current tandem electrostatic accelerator at the Laboratory for Accelerator Beam Applications at the Massachusetts Institute of Technology.

How an integrated change programme has accelerated the reduction in high hazard nuclear facilities at Sellafield

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mackintosh, Angela

For over five decades the Sellafield Site has been central to the UK's nuclear programme. Now operated by Sellafield Ltd, under the management of Parent Body Organisation Nuclear Management Partners (NMP), a consortium of URS Washington Division, AMEC and AREVA is focussed on the decommissioning of historical facilities. When Decommissioning commenced in the late 1980's the site focus at that time was on commercial reprocessing and waste management. Now through the implementation of a company change programme, emphasis has shifted towards accelerated risk and hazard reduction of degraded legacy plants with nuclear inventory whilst ensuring value for money for themore » customer, the Nuclear Decommissioning Authority. This paper will describe the management success by the Site owners in delivering a successful change programme. The paper will explain how the site has transitioned to the INPO Standard Nuclear Performance Model (SNPM) and how through the use of a change maturity matrix has contributed to the accelerated reduction in high risk high hazard nuclear facilities. The paper will explain in detail how the Decommissioning Programme Office has facilitated and coordinated the Governance and assured delivery of the change plan and how successful application of visual management has aided the communication of its progress. Finally, the paper will discuss how the Delivery Schedules have proved critical for presenting the change plan to Key Stakeholders, Government Owners and Powerful Regulators. Overall, this paper provides an insight into how a massive change programme is being managed within one of the world's highest regulated industries. (authors)« less

(Installation of the Vinca Accelerator)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zucker, A.

1991-04-22

I participated in a workshop of the physics with accelerators in Belgrade, Yugoslavia and chaired an advisory committee for the Vinca Accelerator Installation which is currently in progress. Also, I participated in meetings with the Serbian Academy of Sciences and with the Deputy Prime Minister of Serbia concerning the plans and aspirations of the nuclear research center at Vinca.

Evidence for GeV cosmic rays from white dwarfs in the local cosmic ray spectra and in the gamma-ray emissivity of the inner Galaxy

NASA Astrophysics Data System (ADS)

Kamae, Tuneyoshi; Lee, Shiu-Hang; Makishima, Kazuo; Shibata, Shinpei; Shigeyama, Toshikazu

2018-03-01

Recent observations found that electrons are accelerated to ˜10 GeV and emit synchrotron hard X-rays in two magnetic white dwarfs (WDs), also known as cataclysmic variables (CVs). In nova outbursts of WDs, multi-GeV gamma-rays were detected, implying that protons are accelerated to 100 GeV or higher. In recent optical surveys, the WD density is found to be higher near the Sun than in the Galactic disk by a factor ˜2.5. The cosmic rays (CRs) produced by local CVs and novae will accumulate in the local bubble for 106-107 yr. On these findings, we search for CRs from historic CVs and novae in the observed CR spectra. We model the CR spectra at the heliopause as sums of Galactic and local components based on observational data as much as possible. The initial Galactic CR electron and proton spectra are deduced from the gamma-ray emissivity, the local electron spectrum from the hard X-ray spectra at the CVs, and the local proton spectrum from gamma-ray spectra at novae. These spectral shapes are then expressed in a simple set of polynomial functions of CR energy and regressively fitted until the high-energy (>100 GeV) CR spectra near Earth and the Voyager-1 spectra at the heliopause are reproduced. We then extend the modeling to nuclear CR spectra and find that one spectral shape fits all local nuclear CRs, and that the apparent hardening of the nuclear CR spectra is caused by the roll-down of local nuclear spectra around 100-200 GeV. All local CR spectra populate a limited energy band below 100-200 GeV and enhance gamma-ray emissivity below ˜10 GeV. Such an enhancement is observed in the inner Galaxy, suggesting the CR fluxes from CVs and novae are substantially higher there.

Sustained >100 MeV Gamma-Ray Emission: A Monitor for >300 MeV SEP Protons at the Sun

NASA Astrophysics Data System (ADS)

Share, G. H.; Murphy, R. J.

2017-12-01

Solar γ radiation is the product of proton and ion interactions in the solar atmosphere. The spectrum and temporal characteristics of the emission provides fundamental information on the ions at the Sun. Until the launch of the Fermi satellite, with its Large Area Telescope (LAT) sensitive to radiation above 100 MeV, most of the γ-ray observations were made in the nuclear energy range with radiation arising from interaction of one to tens of MeV ions produced in solar flares. Since 2008 the LAT has detected 30 high-energy γ-ray events with temporal and spectral characteristics that are distinct from the associated solar flare. We call this radiation Sustained Gamma-Ray Emission (SGRE) and briefly summarize its characteristics reported in a recent paper. The γ-ray spectra are consistent with pion decay radiation produced by protons above 300 MeV. The onset of the radiation most often occurs after the impulsive flare and the emission can last several hours. We find that the number of protons responsible for the SGRE is typically more than 10 times the number of flare-accelerated protons. These characteristics require that there be an additional source of energy to accelerate the protons to hundreds of MeV to produce the SGRE. As 28 of the 30 SGRE events are accompanied by fast CMEs, it is likely that these protons are accelerated by the same shock that produces gradual SEPs. We find that the number of protons >500 MeV in the accompanying SEPs is typically about 50-100 times the number of protons that return to the Sun to produce the SGRE. There also appear to be correlations between the numbers of SEP and SGRE protons and durations of >100 MeV SEP proton and SGRE events. We find that for all SGRE events where there were flare observations, the accompanying impulsive X-radiation reached energies >100 keV. In a limited study of 18 solar events with CME speeds >800 km/s we also find that the median SEP proton flux is 25 times higher when flare hard X-rays exceed 100 keV. We argue that >100 keV flare X-ray emission is a signature for the presence of hundreds of keV electrons and ions in flares, some of which escape to form a seed population accelerated by CME shocks to produce both the SGRE and the accompanying SEP. This can explain why high-energy SEPs appear to be produced in more significant numbers when a fast CME is accompanied by a flare emitting X-rays >100 keV.

A preliminary study on the use of (10)Be in forensic radioecology of nuclear explosion sites.

PubMed

Whitehead, N E; Endo, S; Tanaka, K; Takatsuji, T; Hoshi, M; Fukutani, S; Ditchburn, R G; Zondervan, A

2008-02-01

Cosmogenic (10)Be, known for use in dating studies, unexpectedly is also produced in nuclear explosions with an atom yield almost comparable to (e.g.) (137)Cs. There are major production routes via (13)C(n, alpha)(10)Be, from carbon dioxide in the air and the organic explosives, possibly from other bomb components and to a minor extent from the direct fission reaction. Although the detailed bomb components are speculative, carbon was certainly present in the explosives and an order of magnitude calculation is possible. The (n, alpha) cross-section was determined by irradiating graphite in a nuclear reactor, and the resulting (10)Be estimated by Accelerator Mass Spectrometry (AMS) giving a cross-section of 34.5+/-0.7mb (6-9.3MeV), within error of previous work. (10)Be should have applications in forensic radioecology. Historical environmental samples from Hiroshima, and Semipalatinsk (Kazakhstan) showed two to threefold (10)Be excesses compared with the background cosmogenic levels. A sample from Lake Chagan (a Soviet nuclear cratering experiment) contained more (10)Be than previously reported soils. (10)Be may be useful for measuring the fast neutron dose near the Hiroshima bomb hypocenter at neutron energies double those previously available.

International Fusion Materials Irradiation Facility injector acceptance tests at CEA/Saclay: 140 mA/100 keV deuteron beam characterization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gobin, R., E-mail: rjgobin@cea.fr; Bogard, D.; Chauvin, N.

In the framework of the ITER broader approach, the International Fusion Materials Irradiation Facility (IFMIF) deuteron accelerator (2 × 125 mA at 40 MeV) is an irradiation tool dedicated to high neutron flux production for future nuclear plant material studies. During the validation phase, the Linear IFMIF Prototype Accelerator (LIPAc) machine will be tested on the Rokkasho site in Japan. This demonstrator aims to produce 125 mA/9 MeV deuteron beam. Involved in the LIPAc project for several years, specialists from CEA/Saclay designed the injector based on a SILHI type ECR source operating at 2.45 GHz and a 2 solenoid lowmore » energy beam line to produce such high intensity beam. The whole injector, equipped with its dedicated diagnostics, has been then installed and tested on the Saclay site. Before shipment from Europe to Japan, acceptance tests have been performed in November 2012 with 100 keV deuteron beam and intensity as high as 140 mA in continuous and pulsed mode. In this paper, the emittance measurements done for different duty cycles and different beam intensities will be presented as well as beam species fraction analysis. Then the reinstallation in Japan and commissioning plan on site will be reported.« less

Detection of Shielded Nuclear Material in a Cargo Container

DOE Office of Scientific and Technical Information (OSTI.GOV)

J. L. Jones; D. R. Norman; K. J. Haskell

The Idaho National Laboratory, along with Los Alamos National Laboratory and the Idaho State University’s Idaho Accelerator Center, are developing electron accelerator-based, photonuclear inspection technologies for the detection of shielded nuclear material within air-, rail-, and especially, maritime-cargo transportation containers. This paper describes a developing prototypical cargo container inspection system utilizing the Pulsed Photonuclear Assessment (PPA) technology, incorporates interchangeable, well-defined, contraband shielding structures (i.e., "calibration" pallets) providing realistic detection data for induced radiation signatures from smuggled nuclear material, and provides various shielded nuclear material detection results. Using a 4.8-kg quantity of depleted uranium, neutron and gamma-ray detection responses are presentedmore » for well-defined shielded and unshielded configurations evaluated in a selected cargo container inspection configuration. © 2001 Elsevier Science. All rights reserved« less

Astrophysical particle acceleration mechanisms in colliding magnetized laser-produced plasmas

DOE PAGES

Fox, W.; Park, J.; Deng, W.; ...

2017-08-11

Significant particle energization is observed to occur in numerous astrophysical environments, and in the standard models, this acceleration occurs alongside energy conversion processes including collisionless shocks or magnetic reconnection. Recent platforms for laboratory experiments using magnetized laser-produced plasmas have opened opportunities to study these particle acceleration processes in the laboratory. Through fully kinetic particle-in-cell simulations, we investigate acceleration mechanisms in experiments with colliding magnetized laser-produced plasmas, with geometry and parameters matched to recent high-Mach number reconnection experiments with externally controlled magnetic fields. 2-D simulations demonstrate significant particle acceleration with three phases of energization: first, a “direct” Fermi acceleration driven bymore » approaching magnetized plumes; second, x-line acceleration during magnetic reconnection of anti-parallel fields; and finally, an additional Fermi energization of particles trapped in contracting and relaxing magnetic islands produced by reconnection. Furthermore, the relative effectiveness of these mechanisms depends on plasma and magnetic field parameters of the experiments.« less

Design of the Next Generation Target at the Lujan Neutron Scattering Center, LANSCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ferres, Laurent

Los Alamos National Laboratory (LANL) supports scientific research in many diverse fields such as biology, chemistry, and nuclear science. The Laboratory was established in 1943 during the Second World War to develop nuclear weapons. Today, LANL is one of the largest laboratories dedicated to nuclear defense and operates an 800 MeV proton linear accelerator for basic and applied research including: production of high- and low-energy neutrons beams, isotope production for medical applications and proton radiography. This accelerator is located at the Los Alamos Neutron Science Center (LANSCE). The work performed involved the redesign of the target for the low-energy neutronmore » source at the Lujan Neutron Scattering Center, which is one of the facilities built around the accelerator. The redesign of the target involves modeling various arrangements of the moderator-reflector-shield for the next generation neutron production target. This is done using Monte Carlo N-Particle eXtended (MCNPX), and ROOT analysis framework, a C++ based-software, to analyze the results.« less

OVERVIEW OF MONO-ENERGETIC GAMMA-RAY SOURCES & APPLICATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartemann, F V; Albert, F; Anderson, G G

2010-05-18

Recent progress in accelerator physics and laser technology have enabled the development of a new class of tunable gamma-ray light sources based on Compton scattering between a high-brightness, relativistic electron beam and a high intensity laser pulse produced via chirped-pulse amplification (CPA). A precision, tunable Mono-Energetic Gamma-ray (MEGa-ray) source driven by a compact, high-gradient X-band linac is currently under development and construction at LLNL. High-brightness, relativistic electron bunches produced by an X-band linac designed in collaboration with SLAC NAL will interact with a Joule-class, 10 ps, diode-pumped CPA laser pulse to generate tunable {gamma}-rays in the 0.5-2.5 MeV photon energymore » range via Compton scattering. This MEGa-ray source will be used to excite nuclear resonance fluorescence in various isotopes. Applications include homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. The source design, key parameters, and current status are presented, along with important applications, including nuclear resonance fluorescence. In conclusion, we have optimized the design of a high brightness Compton scattering gamma-ray source, specifically designed for NRF applications. Two different parameters sets have been considered: one where the number of photons scattered in a single shot reaches approximately 7.5 x 10{sup 8}, with a focal spot size around 8 {micro}m; in the second set, the spectral brightness is optimized by using a 20 {micro}m spot size, with 0.2% relative bandwidth.« less

The importance of becoming double-stranded: Innate immunity and the kinetic model of HIV-1 central plus strand synthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poeschla, Eric, E-mail: poeschla.eric@mayo.edu

Central initiation of plus strand synthesis is a conserved feature of lentiviruses and certain other retroelements. This complication of the standard reverse transcription mechanism produces a transient “central DNA flap” in the viral cDNA, which has been proposed to mediate its subsequent nuclear import. This model has assumed that the important feature is the flapped DNA structure itself rather than the process that produces it. Recently, an alternative kinetic model was proposed. It posits that central plus strand synthesis functions to accelerate conversion to the double-stranded state, thereby helping HIV-1 to evade single-strand DNA-targeting antiviral restrictions such as APOBEC3 proteins,more » and perhaps to avoid innate immune sensor mechanisms. The model is consistent with evidence that lentiviruses must often synthesize their cDNAs when dNTP concentrations are limiting and with data linking reverse transcription and uncoating. There may be additional kinetic advantages for the artificial genomes of lentiviral gene therapy vectors. - Highlights: • Two main functional models for HIV central plus strand synthesis have been proposed. • In one, a transient central DNA flap in the viral cDNA mediates HIV-1 nuclear import. • In the other, multiple kinetic consequences are emphasized. • One is defense against APOBEC3G, which deaminates single-stranded DNA. • Future questions pertain to antiviral restriction, uncoating and nuclear import.« less

First cross-section measurements of the reactions Ag,109107(p ,γ )Cd,110108 at energies relevant to the p process

NASA Astrophysics Data System (ADS)

Khaliel, A.; Mertzimekis, T. J.; Asimakopoulou, E.-M.; Kanellakopoulos, A.; Lagaki, V.; Psaltis, A.; Psyrra, I.; Mavrommatis, E.

2017-09-01

Background: One of the primary objectives of the field of Nuclear Astrophysics is the study of the elemental and isotopic abundances in the universe. Although significant progress has been made in understanding the mechanisms behind the production of a large number of nuclides in the isotopic chart, there are still many open questions regarding a number of neutron-deficient nuclei, the p nuclei. To that end, experimentally deduced nuclear reaction cross sections can provide invaluable input to astrophysical models. Purpose: The reactions Ag,109107(p ,γ )Cd,110108 have been studied at energies inside the astrophysically relevant energy window in an attempt to provide experimental data required for the testing of reaction-rate predictions in terms of the statistical model of Hauser-Feshbach around the p nucleus 108Cd. Methods: The experiments were performed with in-beam γ -ray spectroscopy with proton beams accelerated by the Tandem Van de Graaff Accelerator at NCSR "Demokritos" impinging a target of natural silver. A set of high-purity germanium detectors was employed to record the emitted radiation. Results: A first set of total cross-section measurements in radiative proton-capture reactions involving Ag,109107, producing the p -nucleus 108Cd, inside the astrophysically relevant energy window is reported. The experimental results are compared to theoretical calculations, using talys. An overall good agreement between the data and the theoretical calculations has been found. Conclusions: The results reported in this work add new information to the relatively unexplored p process. The present measurements can serve as a reference point in understanding the nuclear parameters in the related astrophysical environments and for future theoretical modeling and experimental works.

Using the nuclear activation AMS method for determining chlorine in solids at ppb-levels and below

NASA Astrophysics Data System (ADS)

Winkler, Stephan R.; Eigl, Rosmarie; Forstner, Oliver; Martschini, Martin; Steier, Peter; Sterba, Johannes H.; Golser, Robin

2015-10-01

Neutron activation analysis using decay counting of the activated element is a well-established method in elemental analysis. However, for chlorine there is a better alternative to measuring decay of the short-lived activation product chlorine-38 (t1/2 = 37.24 min) - accelerator mass spectrometry (AMS) of 36Cl: the relatively high neutron capture cross section of chlorine-35 for thermal neutrons (43.7 b) and combined the AMS technique for chlorine-36 (t1/2 = 301 ka) allow for determination of chlorine down to ppb-levels using practical sample sizes and common exposure durations. The combination of neutron activation and AMS can be employed for a few other elements (nitrogen, thorium, and uranium) as well. For bulk solid samples an advantage of the method is that lab contamination can be rendered irrelevant. The chlorine-35 in the sample is activated to chlorine-36, and surface chlorine can be removed after the irradiation. Subsequent laboratory contamination, however, will not carry a prominent chlorine-36 signature. After sample dissolution and addition of sufficient amounts of stable chlorine carrier the produced chlorine-36 and thus the original chlorine-35 of the sample can be determined using AMS. We have developed and applied the method for analysis of chlorine in steel samples. The chlorine content of steel is of interest to nuclear industry, precisely because of above mentioned high neutron capture cross section for chlorine-35, which leads to accumulation of chlorine-36 as long-term nuclear waste. The samples were irradiated at the TRIGA Mark II reactor of the Atominstitut in Vienna and the 36Cl-AMS setup at the Vienna Environmental Research Accelerator (VERA) was used for 36Cl/Cl analysis.

Time-Resolved Tandem Faraday Cup Development for High Energy TNSA Particles

NASA Astrophysics Data System (ADS)

Padalino, S.; Simone, A.; Turner, E.; Ginnane, M. K.; Glisic, M.; Kousar, B.; Smith, A.; Sangster, C.; Regan, S.

2015-11-01

MTW and OMEGA EP Lasers at LLE utilize ultra-intense laser light to produce high-energy ion pulses through Target Normal Sheath Acceleration (TNSA). A Time Resolved Tandem Faraday Cup (TRTF) was designed and built to collect and differentiate protons from heavy ions (HI) produced during TNSA. The TRTF includes a replaceable thickness absorber capable of stopping a range of user-selectable HI emitted from TNSA plasma. HI stop within the primary cup, while less massive particles continue through and deposit their remaining charge in the secondary cup, releasing secondary electrons in the process. The time-resolved beam current generated in each cup will be measured on a fast storage scope in multiple channels. A charge-exchange foil at the TRTF entrance modifies the charge state distribution of HI to a known distribution. Using this distribution and the time of flight of the HI, the total HI current can be determined. Initial tests of the TRTF have been made using a proton beam produced by SUNY Geneseo's 1.7 MV Pelletron accelerator. A substantial reduction in secondary electron production, from 70% of the proton beam current at 2MeV down to 0.7%, was achieved by installing a pair of dipole magnet deflectors which successfully returned the electrons to the cups in the TRTF. Ultimately the TRTF will be used to normalize a variety of nuclear physics cross sections and stopping power measurements. Based in part upon work supported by a DOE NNSA Award#DE-NA0001944.

Continuous wave superconducting radio frequency electron linac for nuclear physics research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reece, Charles E.

CEBAF, the Continuous Electron Beam Accelerator Facility, has been actively serving the nuclear physics research community as a unique forefront international resource since 1995. This cw electron linear accelerator (linac) at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility (Jefferson Lab) has continued to evolve as a precision tool for discerning the structure and dynamics within nuclei. Superconducting rf (SRF) technology has been the essential foundation for CEBAF, first as a 4 GeV machine, then 6 GeV, and currently capable of 12 GeV. Lastly, we review the development, implementation, and performance of SRF systems for CEBAF from itsmore » early beginnings to the commissioning of the 12 GeV era.« less

Continuous wave superconducting radio frequency electron linac for nuclear physics research

DOE PAGES

Reece, Charles E.

2016-12-28

CEBAF, the Continuous Electron Beam Accelerator Facility, has been actively serving the nuclear physics research community as a unique forefront international resource since 1995. This cw electron linear accelerator (linac) at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility (Jefferson Lab) has continued to evolve as a precision tool for discerning the structure and dynamics within nuclei. Superconducting rf (SRF) technology has been the essential foundation for CEBAF, first as a 4 GeV machine, then 6 GeV, and currently capable of 12 GeV. Lastly, we review the development, implementation, and performance of SRF systems for CEBAF from itsmore » early beginnings to the commissioning of the 12 GeV era.« less

Present status of Accelerator-Based BNCT.

PubMed

Kreiner, Andres Juan; Bergueiro, Javier; Cartelli, Daniel; Baldo, Matias; Castell, Walter; Asoia, Javier Gomez; Padulo, Javier; Suárez Sandín, Juan Carlos; Igarzabal, Marcelo; Erhardt, Julian; Mercuri, Daniel; Valda, Alejandro A; Minsky, Daniel M; Debray, Mario E; Somacal, Hector R; Capoulat, María Eugenia; Herrera, María S; Del Grosso, Mariela F; Gagetti, Leonardo; Anzorena, Manuel Suarez; Canepa, Nicolas; Real, Nicolas; Gun, Marcelo; Tacca, Hernán

2016-01-01

This work aims at giving an updated report of the worldwide status of Accelerator-Based BNCT (AB-BNCT). There is a generalized perception that the availability of accelerators installed in hospitals, as neutron sources, may be crucial for the advancement of BNCT. Accordingly, in recent years a significant effort has started to develop such machines. A variety of possible charged-particle induced nuclear reactions and the characteristics of the resulting neutron spectra are discussed along with the worldwide activity in suitable accelerator development. Endothermic (7)Li(p,n)(7)Be and (9)Be(p,n)(9)B and exothermic (9)Be(d,n)(10)B are compared. In addition to having much better thermo-mechanical properties than Li, Be as a target leads to stable products. This is a significant advantage for a hospital-based facility. (9)Be(p,n)(9)B needs at least 4-5 MeV bombarding energy to have a sufficient yield, while (9)Be(d,n)(10)B can be utilized at about 1.4 MeV, implying the smallest possible accelerator. This reaction operating with a thin target can produce a sufficiently soft spectrum to be viable for AB-BNCT. The machines considered are electrostatic single ended or tandem accelerators or radiofrequency quadrupoles plus drift tube Linacs. (7)Li(p,n)(7)Be provides one of the best solutions for the production of epithermal neutron beams for deep-seated tumors. However, a Li-based target poses significant technological challenges. Hence, Be has been considered as an alternative target, both in combination with (p,n) and (d,n) reactions. (9)Be(d,n)(10)B at 1.4 MeV, with a thin target has been shown to be a realistic option for the treatment of deep-seated lesions.

Amplitude-dependent orbital period in alternating gradient accelerators

DOE PAGES

Machida, S.; Kelliher, D. J.; Edmonds, C. S.; ...

2016-03-16

Orbital period in a ring accelerator and time of flight in a linear accelerator depend on the amplitude of betatron oscillations. The variation is negligible in ordinary particle accelerators with relatively small beam emittance. In an accelerator for large emittance beams like muons and unstable nuclei, however, this effect cannot be ignored. In this study, we measured orbital period in a linear non-scaling fixed-field alternating-gradient accelerator, which is a candidate for muon acceleration, and compared it with the theoretical prediction. The good agreement between them gives important ground for the design of particle accelerators for a new generation of particlemore » and nuclear physics experiments.« less

The Proton Synchrotron (PS): At the Core of the CERN Accelerators

NASA Astrophysics Data System (ADS)

Cundy, Donald; Gilardoni, Simone

The following sections are included: * Introduction * Extraction: Getting the Beam to Leave the Accelerator * Acceleration and Bunch Gymnastics * Boosting PS Beam Intensity * Capacitive Energy Storage Replaces Flywheel * Taking the Neutrinos by the Horns * OMEGA: Towards the Electronic Bubble Chamber * ISOLDE: Targeting a New Era in Nuclear Physics * The CERN n_TOF Facility: Catching Neutrons on the Fly * References

Failla Memorial lecture. The future of heavy-ion science in biology and medicine.

PubMed

Tobias, C A

1985-07-01

Interplanetary space contains fluxes of fast moving atomic nuclei. The distribution of these reflects the atomic composition of the universe, and such particles may pose limitations for space flight and for life in space. Over the past 50 years, since the invention of Ernest Lawrence's cyclotron, advances in accelerator technology have permitted the acceleration of charged nuclei to very high velocities. Currently, beams of any stable isotope species up to uranium are available at kinetic energies of several hundred MeV/nucleon at the Berkeley Bevalac. Recently, new areas of particle physics research relating to the mechanisms of spallation and fission have opened up for investigation, and it is now realistic to search for nuclear super-dense states that might be produced in heavy nuclear collisions. The heavy ions hold interest for a broad spectrum of research because of their effectiveness in producing a series of major lesions in DNA along single particle tracks and because of the Bragg depth ionization properties that allow the precise deposition of highly localized doses deep in the human body. Individual heavy ions can also interrupt the continuity of membraneous regions in cells. Heavy ions, when compared to low-LET radiation, have increased effectiveness for mammalian cell lethality, chromosome mutations, and cell transformation. The molecular mechanisms are not completely understood but appear to involve fragmentation and reintegration of DNA. Cells attempt to repair these lesions, and many of the deleterious effects are due to misrepair or misrejoining of DNA. Heavy ions do not require the presence of oxygen for producing their effects, and hypoxic cells in necrotic regions have nearly the same sensitivity as cells in well-oxygenated tissues. Heavy ions are effective in delaying or blocking the cell division process. Heavy ions are also strong enhancers of viral-induced cell transformation, a process that requires integration of foreign DNA. Some cell lines, known to be radioresistant to X rays, have exhibited greater sensitivity to heavy ions. These radiobiological properties, combined with the ability to deliver highly localized internal doses, make accelerated heavy ions potentially important radiotherapeutic tools. Other novel approaches include the utilization of radioactive heavy beams as instant tracers. Heavy-ion radiography and microscopy respond to delicate changes in tissue electron density. Dose localization with helium ions has achieved excellent results for pituitary tumors, tumors adjacent to the spinal cord, and ocular melanomas. We are working on adapting silicon- and neon-ion beams for controlled therapy studies.(ABSTRACT TRUNCATED AT 400 WORDS)

National Biomedical Tracer Facility. Project definition study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schafer, R.

We request a $25 million government-guaranteed, interest-free loan to be repaid over a 30-year period for construction and initial operations of a cyclotron-based National Biomedical Tracer Facility (NBTF) in North Central Texas. The NBTF will be co-located with a linear accelerator-based commercial radioisotope production facility, funded by the private sector at approximately $28 million. In addition, research radioisotope production by the NBTF will be coordinated through an association with an existing U.S. nuclear reactor center that will produce research and commercial radioisotopes through neutron reactions. The combined facilities will provide the full range of technology for radioisotope production and research:more » fast neutrons, thermal neutrons, and particle beams (H{sup -}, H{sup +}, and D{sup +}). The proposed NBTF facility includes an 80 MeV, 1 mA H{sup -} cyclotron that will produce proton-induced (neutron deficient) research isotopes.« less

Student research with 400keV beams: {sup 13}N radioisotope production target development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fru, L. Che; Clymer, J.; Compton, N.

2013-04-19

The AN400 Van de Graaff accelerator at the Minnesota State University, Mankato, Applied Nuclear Science Lab has demonstrated utility as an accessible and versatile platform for student research. Despite the limits of low energy, the research team successfully developed projects with applications to the wider radioisotope production community. A target system has been developed for producing and extracting {sup 13}N by the {sup 12}C(d,n){sup 13}N reaction below 400keV. The system is both reusable and robust, with future applications to higher energy machines producing this important radioisotope for physiological imaging studies with Positron Emission Tomography. Up to 36({+-}1)% of the {supmore » 13}N was extracted from the graphite matrix when 35 A current was externally applied to the graphite target while simultaneously flushing the target chamber with CO{sub 2} gas.« less

Anuglar distribution of shower particles produced in the collisions of 20-GeV/c and 300-GeV negative pions with emulsion nuclei

NASA Technical Reports Server (NTRS)

Kim, C. O.; Kim, S. N.; Park, I. G.; Yoon, C. S.

1983-01-01

For 435 accelerator produced antipions jets of 20 GeV/c and 300 GeV, in nuclear emulsion, eta(theta)'s have been individually calculated for each jet, where eta(theta) is a kinematic parameter introduced in order to approximate the LS (laboratory system) rapidity, eta = arctan h (beta cos theta). By taking further averages by dividing the samples into groupings of the LS energy E sub pi = m cos h eta sub pi N sub h, the number of heavy prongs with LS velocity beta 0.7, and n , the number of charged shower particles with LS velocity beta 0.7, much less than eta (theta) much greater than are obtained. By use of the KNO (Koba-Nielsen-Olesen) scaling variable, xi = n sub s/,n sub s. good fit is found of data to regression function.

Nuclear astrophysics at Gran Sasso Laboratory: the LUNA experiment

NASA Astrophysics Data System (ADS)

Cavanna, Francesca

2018-05-01

LUNA is an experimental approach for the study of nuclear fusion reactions based on an underground accelerator laboratory. Aim of the experiment is the direct measurement of the cross section of nuclear reactions relevant for stellar and primordial nucleosynthesis. In the following the latest results and the future goals will be presented.

White paper on nuclear astrophysics and low energy nuclear physics Part 1: Nuclear astrophysics

DOE PAGES

Arcones, Almudena; Bardayan, Dan W.; Beers, Timothy C.; ...

2016-12-28

This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It also summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21–23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9–10, 2012more » Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). Our white paper is informed informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12–13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. Answers to long standing key questions are well within reach in the coming decade because of the developments outlined in this white paper.« less

White paper on nuclear astrophysics and low energy nuclear physics Part 1: Nuclear astrophysics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arcones, Almudena; Bardayan, Dan W.; Beers, Timothy C.

This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It also summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21–23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9–10, 2012more » Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). Our white paper is informed informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12–13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. Answers to long standing key questions are well within reach in the coming decade because of the developments outlined in this white paper.« less

White Paper on Nuclear Astrophysics and Low Energy Nuclear Physics - Part 1. Nuclear Astrophysics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arcones, Almudena; Escher, Jutta E.; Others, M.

This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21 - 23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9more » - 10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12 - 13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. With the developments outlined in this white paper, answers to long-standing key questions are well within reach in the coming decade.« less

White paper on nuclear astrophysics and low energy nuclear physics Part 1: Nuclear astrophysics

NASA Astrophysics Data System (ADS)

Arcones, Almudena; Bardayan, Dan W.; Beers, Timothy C.; Bernstein, Lee A.; Blackmon, Jeffrey C.; Messer, Bronson; Brown, B. Alex; Brown, Edward F.; Brune, Carl R.; Champagne, Art E.; Chieffi, Alessandro; Couture, Aaron J.; Danielewicz, Pawel; Diehl, Roland; El-Eid, Mounib; Escher, Jutta E.; Fields, Brian D.; Fröhlich, Carla; Herwig, Falk; Hix, William Raphael; Iliadis, Christian; Lynch, William G.; McLaughlin, Gail C.; Meyer, Bradley S.; Mezzacappa, Anthony; Nunes, Filomena; O'Shea, Brian W.; Prakash, Madappa; Pritychenko, Boris; Reddy, Sanjay; Rehm, Ernst; Rogachev, Grigory; Rutledge, Robert E.; Schatz, Hendrik; Smith, Michael S.; Stairs, Ingrid H.; Steiner, Andrew W.; Strohmayer, Tod E.; Timmes, F. X.; Townsley, Dean M.; Wiescher, Michael; Zegers, Remco G. T.; Zingale, Michael

2017-05-01

This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21-23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9-10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12-13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. With the developments outlined in this white paper, answers to long standing key questions are well within reach in the coming decade.

United States and Russian Cooperation on Issues of Nuclear Nonproliferation

DTIC Science & Technology

2005-06-01

Reactors ( RERTR ) This project works with Russia to facilitate conversion of its research and test reactors from highly enriched uranium (HEU) fuel...reactor fuel purchase, accelerated RERTR activities, and accelerated Material Conversion and Consolidation implementation. 89 j. Fissile Materials

Brookhaven highlights, October 1978-September 1979. [October 1978 to September 1979

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-01-01

These highlights present an overview of the major research and development achievements at Brookhaven National Laboratory from October 1978 to September 1979. Specific areas covered include: accelerator and high energy physics programs; high energy physics research; the AGS and improvements to the AGS; neutral beam development; heavy ion fusion; superconducting power cables; ISABELLE storage rings; the BNL Tandem accelerator; heavy ion experiments at the Tandem; the High Flux Beam Reactor; medium energy physics; nuclear theory; atomic and applied physics; solid state physics; neutron scattering studies; x-ray scattering studies; solid state theory; defects and disorder in solids; surface physics; the Nationalmore » Synchrotron Light Source ; Chemistry Department; Biology Department; Medical Department; energy sciences; environmental sciences; energy technology programs; National Center for Analysis of Energy Systems; advanced reactor systems; nuclear safety; National Nuclear Data Center; nuclear materials safeguards; Applied Mathematics Department; and support activities. (GHT)« less

Cyclotron Production of Radionuclides for Nuclear Medicine at Academic Centers

NASA Astrophysics Data System (ADS)

Lapi, Suzanne

2016-09-01

The increase in use of radioisotopes for medical imaging has led to the development of new accelerator targetry and separation techniques for isotope production. For example, the development of longer-lived position emitting radionuclides has been explored to allow for nuclear imaging agents based on peptides, antibodies and nanoparticles. These isotopes (64Cu, 89Zr, 86Y) are typically produced via irradiation of solid targets on smaller cyclotrons (10-25 MeV) at academic or hospital based facilities. Recent research has further expanded the toolbox of PET tracers to include additional isotopes such as 52Mn, 55Co, 76Br and others. The smaller scale of these types of facilities can enable the straightforward involvement of students, thus adding to the next generation of nuclear science leaders. Research pertaining to development of robust and larger scale production technologies including solid target systems and remote systems for transport and purification of these isotopes has enabled both preclinical and clinical imaging research for many diseases. In particular, our group has focused on the use of radiolabeled antibodies for imaging of receptor expression in preclinical models and in a clinical trial of metastatic breast cancer patients.

Discovery of naked charm particles and lifetime differences among charm species using nuclear emulsion techniques innovated in Japan

PubMed Central

NIU, Kiyoshi

2008-01-01

This is a historical review of the discovery of naked charm particles and lifetime differences among charm species. These discoveries in the field of cosmic-ray physics were made by the innovation of nuclear emulsion techniques in Japan. A pair of naked charm particles was discovered in 1971 in a cosmic-ray interaction, three years prior to the discovery of the hidden charm particle, J/Ψ, in western countries. Lifetime differences between charged and neutral charm particles were pointed out in 1975, which were later re-confirmed by the collaborative Experiment E531 at Fermilab. Japanese physicists led by K.Niu made essential contributions to it with improved emulsion techniques, complemented by electronic detectors. This review also discusses the discovery of artificially produced naked charm particles by us in an accelerator experiment at Fermilab in 1975 and of multiple-pair productions of charm particles in a single interaction in 1987 by the collaborative Experiment WA75 at CERN. PMID:18941283

The Neutrons for Science Facility at SPIRAL-2

NASA Astrophysics Data System (ADS)

Ledoux, X.; Aïche, M.; Avrigeanu, M.; Avrigeanu, V.; Audouin, L.; Balanzat, E.; Ban-d'Etat, B.; Ban, G.; Barreau, G.; Bauge, E.; Bélier, G.; Bem, P.; Blideanu, V.; Blomgren, J.; Borcea, C.; Bouffard, S.; Caillaud, T.; Chatillon, A.; Czajkowski, S.; Dessagne, P.; Doré, D.; Fallot, M.; Farget, F.; Fischer, U.; Giot, L.; Granier, T.; Guillous, S.; Gunsing, F.; Gustavsson, C.; Herber, S.; Jacquot, B.; Jurado, B.; Kerveno, M.; Klix, A.; Landoas, O.; Lecolley, F. R.; Lecolley, J. F.; Lecouey, J. L.; Majerle, M.; Marie, N.; Materna, T.; Mrazek, J.; Negoita, F.; Novak, J.; Oberstedt, S.; Oberstedt, A.; Panebianco, S.; Perrot, L.; Petrascu, M.; Plompen, A. J. M.; Pomp, S.; Ramillon, J. M.; Ridikas, D.; Rossé, B.; Rudolf, G.; Serot, O.; Shcherbakov, O.; Simakov, S. P.; Simeckova, E.; Smith, A. G.; Steckmeyer, J. C.; Sublet, J. C.; Taïeb, J.; Tassan-Got, L.; Takibayev, A.; Tungborn, E.; Thfoin, I.; Tsekhanovich, I.; Varignon, C.; Wieleczko, J. P.

2011-12-01

The "Neutrons for Science" (NFS) facility will be a component of SPIRAL-2, the future accelerator dedicated to the production of very intense radioactive ion beams, under construction at GANIL in Caen (France). NFS will be composed of a pulsed neutron beam for in-flight measurements and irradiation stations for cross-section measurements and material studies. Continuous and quasi-monokinetic energy spectra will be available at NFS respectively produced by the interaction of deuteron beam on thick a Be converter and by the 7Li(p,n) reaction on a thin converter. The flux at NFS will be up to 2 orders of magnitude higher than those of other existing time-of-flight facilities in the 1 MeV to 40 MeV range. NFS will be a very powerful tool for physics and fundamental research as well as applications like the transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ledoux, X.; Bauge, E.; Belier, G.

The ''Neutrons for Science''(NFS) facility will be a component of SPIRAL-2, the future accelerator dedicated to the production of very intense radioactive ion beams, under construction at GANIL in Caen (France). NFS will be composed of a pulsed neutron beam for in-flight measurements and irradiation stations for cross-section measurements and material studies. Continuous and quasi-monokinetic energy spectra will be available at NFS respectively produced by the interaction of deuteron beam on thick a Be converter and by the {sup 7}Li(p,n) reaction on a thin converter. The flux at NFS will be up to 2 orders of magnitude higher than thosemore » of other existing time-of-flight facilities in the 1 MeV to 40 MeV range. NFS will be a very powerful tool for physics and fundamental research as well as applications like the transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors.« less

Upgrades at the Duke Free Electron Laser Laboratory

NASA Astrophysics Data System (ADS)

Howell, Calvin R.

2004-11-01

Major upgrades to the storage-ring based photon sources at the Duke Free Electron Laser Laboratory (DFELL) are underway. The photon sources at the DFELL are well suited for research in the areas of medicine, biophysics, accelerator physics, nuclear physics and material science. These upgrades, which will be completed by the summer 2006, will significantly enhance the capabilities of the ultraviolet (UV) free-electron laser (FEL) and the high intensity gamma-ray source (HIGS). The HIGS is a relatively new research facility at the DFELL that is operated jointly by the DFELL and the Triangle Universities Nuclear Laboratory. The gamma-ray beam is produced by Compton back scattering of the UV photons inside the FEL optical cavity off the circulating electrons in the storage ring. The gamma-ray beam is 100% polarized and its energy resolution is selected by collimation. The capabilities of the upgraded facility will be described, the status of the upgrades will be summarized, and the proposed first-generation research program at HIGS will be presented.

Operating experience with a VMEbus multiprocessor system for data acquisition and reduction in nuclear physics

NASA Astrophysics Data System (ADS)

Kutt, P. H.; Balamuth, D. P.

1989-10-01

Summary form only given, as follows. A multiprocessor system based on commercially available VMEbus components has been developed for the acquisition and reduction of event-mode data in nuclear physics experiments. The system contains seven 68000 CPUs and 14 Mbyte of memory. A minimal operating system handles data transfer and task allocation, and a compiler for a specially designed event analysis language produces code for the processors. The system has been in operation for four years at the University of Pennsylvania Tandem Accelerator Laboratory. Computation rates over three times that of a MicroVAX II have been achieved at a fraction of the cost. The use of WORM optical disks for event recording allows the processing of gigabyte data sets without operator intervention. A more powerful system is being planned which will make use of recently developed RISC (reduced instruction set computer) processors to obtain an order of magnitude increase in computing power per node.

Accelerating CR-39 Track Detector Processing by Utilizing UV

NASA Astrophysics Data System (ADS)

Sparling, Jonathan; Padalino, Stephen; McLean, James; Sangster, Craig; Regan, Sean

2017-10-01

The use of CR-39 plastic as a Solid State Nuclear Track Detector is an effective technique for obtaining data in high energy particle experiments including inertial confinement fusion. To reveal particle tracks after irradiation, CR-39 is chemically etched in NaOH at 80°C, producing micron-scale signal pits at the nuclear track sites. It has been shown that illuminating CR-39 with UV light prior to etching increases bulk and track etch rates, especially when combined with elevated temperature. Spectroscopic analysis for amorphous solids has helped identify which UV wavelengths are most effective at enhancing etch rates. Absorption peaks found in the near infrared range provide for efficient sample heating, and may allow targeting cooperative IR-UV chemistry. Avoiding UV induced noise can be achieved through variations in absorption depths with wavelength. Vacuum drying and water absorption tests allow measurement of the resulting variation of bulk etch rate with depth. Funded in part by the NSF and an Department of Energy Grant through the Lab of Laser Energetics.

Radiation Transport Calculation of the UGXR Collimators for the Jules Horowitz Reactor (JHR)

NASA Astrophysics Data System (ADS)

Chento, Yelko; Hueso, César; Zamora, Imanol; Fabbri, Marco; Fuente, Cristina De La; Larringan, Asier

2017-09-01

Jules Horowitz Reactor (JHR), a major infrastructure of European interest in the fission domain, will be built and operated in the framework of an international cooperation, including the development and qualification of materials and nuclear fuel used in nuclear industry. For this purpose UGXR Collimators, two multi slit gamma and X-ray collimation mechatronic systems, will be installed at the JHR pool and at the Irradiated Components Storage pool. Expected amounts of radiation produced by the spent fuel and X-ray accelerator implies diverse aspects need to be verified to ensure adequate radiological zoning and personnel radiation protection. A computational methodology was devised to validate the Collimators design by means of coupling different engineering codes. In summary, several assessments were performed by means of MCNP5v1.60 to fulfil all the radiological requirements in Nominal scenario (TEDE < 25µSv/h) and in Maintenance scenario (TEDE < 2mSv/h) among others, detailing the methodology, hypotheses and assumptions employed.

Dense plasma focus (DPF) accelerated non radio isotopic radiological source

DOEpatents

Rusnak, Brian; Tang, Vincent

2017-01-31

A non-radio-isotopic radiological source using a dense plasma focus (DPF) to produce an intense z-pinch plasma from a gas, such as helium, and which accelerates charged particles, such as generated from the gas or injected from an external source, into a target positioned along an acceleration axis and of a type known to emit ionizing radiation when impinged by the type of accelerated charged particles. In a preferred embodiment, helium gas is used to produce a DPF-accelerated He2+ ion beam to a beryllium target, to produce neutron emission having a similar energy spectrum as a radio-isotopic AmBe neutron source. Furthermore, multiple DPFs may be stacked to provide staged acceleration of charged particles for enhancing energy, tunability, and control of the source.

Generation of femtosecond γ-ray bursts stimulated by laser-driven hosing evolution

PubMed Central

Ma, Yong; Chen, Liming; Li, Dazhang; Yan, Wenchao; Huang, Kai; Chen, Min; Sheng, Zhengming; Nakajima, Kazuhisa; Tajima, Toshiki; Zhang, Jie

2016-01-01

The promising ability of a plasma wiggler based on laser wakefield acceleration to produce betatron X-rays with photon energies of a few keV to hundreds of keV and a peak brilliance of 1022–1023 photons/s/mm2/mrad2/0.1%BW has been demonstrated, providing an alternative to large-scale synchrotron light sources. Most methods for generating betatron radiation are based on two typical approaches, one relying on an inherent transverse focusing electrostatic field, which induces transverse oscillation, and the other relying on the electron beam catching up with the rear part of the laser pulse, which results in strong electron resonance. Here, we present a new regime of betatron γ-ray radiation generated by stimulating a large-amplitude transverse oscillation of a continuously injected electron bunch through the hosing of the bubble induced by the carrier envelope phase (CEP) effect of the self-steepened laser pulse. Our method increases the critical photon energy to the MeV level, according to the results of particle-in-cell (PIC) simulations. The highly collimated, energetic and femtosecond γ-ray bursts that are produced in this way may provide an interesting potential means of exploring nuclear physics in table top photo nuclear reactions. PMID:27457890

Reduce, reuse and recycle: a green solution to Canada's medical isotope shortage.

PubMed

Galea, R; Ross, C; Wells, R G

2014-05-01

Due to the unforeseen maintenance issues at the National Research Universal (NRU) reactor at Chalk River and coincidental shutdowns of other international reactors, a global shortage of medical isotopes (in particular technetium-99m, Tc-99m) occurred in 2009. The operation of these research reactors is expensive, their age creates concerns about their continued maintenance and the process results in a large amount of long-lived nuclear waste, whose storage cost has been subsidized by governments. While the NRU has since revived its operations, it is scheduled to cease isotope production in 2016. The Canadian government created the Non-reactor based medical Isotope Supply Program (NISP) to promote research into alternative methods for producing medical isotopes. The NRC was a member of a collaboration looking into the use of electron linear accelerators (LINAC) to produce molybdenum-99 (Mo-99), the parent isotope of Tc-99m. This paper outlines NRC's involvement in every step of this process, from the production, chemical processing, recycling and preliminary animal studies to demonstrate the equivalence of LINAC Tc-99m with the existing supply. This process stems from reusing an old idea, reduces the nuclear waste to virtually zero and recycles material to create a green solution to Canada's medical isotope shortage. © 2013 Published by Elsevier Ltd.

Compact Fuel Element Environment Test

NASA Technical Reports Server (NTRS)

Bradley, D. E.; Mireles, O. R.; Hickman, R. R.; Broadway, J. W.

2012-01-01

Deep space missions with large payloads require high specific impulse (I(sub sp)) and relatively high thrust to achieve mission goals in reasonable time frames. Conventional, storable propellants produce average I(sub sp). Nuclear thermal rockets (NTRs) capable of high I(sub sp) thrust have been proposed. NTR employs heat produced by fission reaction to heat and therefore accelerate hydrogen, which is then forced through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3,000 K) and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high-temperature hydrogen exposure on fuel elements are limited. The primary concern is the mechanical failure of fuel elements that employ high melting point metals, ceramics, or a combination (cermet) as a structural matrix into which the nuclear fuel is distributed. It is not necessary to include fissile material in test samples intended to explore high-temperature hydrogen exposure of the structural support matrices. A small-scale test bed designed to heat fuel element samples via noncontact radio frequency heating and expose samples to hydrogen for typical mission durations has been developed to assist in optimal material and manufacturing process selection without employing fissile material. This Technical Memorandum details the test bed design and results of testing conducted to date.

Feasibility studies towards future self-sufficient supply of the 99Mo-99mTc isotopes with Japanese accelerators

PubMed Central

NAKAI, Kozi; TAKAHASHI, Naruto; HATAZAWA, Jun; SHINOHARA, Atsushi; HAYASHI, Yoshihiko; IKEDA, Hayato; KANAI, Yasukazu; WATABE, Tadashi; FUKUDA, Mitsuhiro; HATANAKA, Kichiji

2014-01-01

In order to establish a self-sufficient supply of 99mTc, we studied feasibilities to produce its parent nucleus, 99Mo, using Japanese accelerators. The daughter nucleus, 99mTc, is indispensable for medical diagnosis. 99Mo has so far been imported from abroad, which is separated from fission products generated in nuclear reactors using enriched 235U fuel. We investigated 99mTc production possibilities based on the following three scenarios: (1) 99Mo production by the (n, 2n) reaction by spallation neutrons at the J-PARC injector, LINAC; (2) 99Mo production by the (p, pn) reaction at Ep = 50–80 MeV proton at the RCNP cyclotron; (3) 99mTc direct production with a 20 MeV proton beam from the PET cyclotron. Among these three scenarios, scenario (1) is for a scheme on a global scale, scenario (2) works in a local area, and both cases take a long time for negotiations. Scenario (3) is attractive because we can use nearly 50 PET cyclotrons in Japan for 99mTc production. We here consider both the advantages and disadvantages among the three scenarios by taking account of the Japanese accelerator situation. PMID:25504230

Can Accelerators Meet the Medical Isotopes Needs of the World?

NASA Astrophysics Data System (ADS)

Ruth, Thomas

2011-10-01

Over 80% of all Nuclear Medicine procedures make use of the radionuclide Tc-99 for SPECT imaging of heart disease, cancer and other disorders. Historically TC-99 has been produced from a generator through the decay of Mo-99 where the Mo-99 is a fission product of U-235. Five reactors around the world supply the market. However, these reactors are aging (many over 50 years old) and governments are reluctant to replace them. Therefore researchers have turned to accelerators as a potential source of this important radionuclide. In Canada the government has funded research project for two accelerator approaches: Mo-100(gamma,n)Mo-99 and Mo-100(p,2n)Tc-99m where the photons are generated from the conversion of high powered electrons into Bremsstrahlung radiation and the protons generated in low energy cyclotrons (15-25 MeV). The goal of these project is to provide the Government with sufficient information so that an informed decision can be made with respect to future supplies of medical isotopes for Canada. International interest has been expressed by the IAEA as a way to allow Member States with existing cyclotron programs to take advantage of the direct production route. This talk will describe the challenges with the approaches and the progress to date.

Detectors for the gamma-ray resonant absorption (GRA) method of explosives detection in cargo: a comparative study

NASA Astrophysics Data System (ADS)

Vartsky, David; Goldberg, Mark B.; Engler, Gideon; Shor, Asher; Goldschmidt, Aharon; Feldman, Gennady; Bar, Doron; Orion, Itzhak; Wielopolski, Lucian

2004-01-01

Gamma-Ray Resonant Absorption (GRA) is an automatic-decision radiographic screening technique that combines high radiation penetration with very good sensitivity and specificity to nitrogenous explosives. The method is particularly well-suited to inspection of large, massive objects (since the resonant γ-ray probe is at 9.17 MeV) such as aviation and marine containers, heavy vehicles and railroad cars. Two kinds of γ-ray detectors have been employed to date in GRA systems: 1) Resonant-response nitrogen-rich liquid scintillators and 2) BGO detectors. This paper analyses and compares the response of these detector-types to the resonant radiation, in terms of single-pixel figures of merit. The latter are sensitive not only to detector response, but also to accelerator-beam quality, via the properties of the nuclear reaction that produces the resonant-γ-rays. Generally, resonant detectors give rise to much higher nitrogen-contrast sensitivity in the radiographic image than their non-resonant detector counterparts and furthermore, do not require proton beams of high energy-resolution. By comparison, the non-resonant detectors have higher γ-detection efficiency, but their contrast sensitivity is very sensitive to the quality of the accelerator beam. Implications of these detector/accelerator characteristics for eventual GRA field systems are discussed.

Upgrade of the MIT Linear Electrostatic Ion Accelerator (LEIA) for nuclear diagnostics development for Omega, Z and the NIF.

PubMed

Sinenian, N; Manuel, M J-E; Zylstra, A B; Rosenberg, M; Waugh, C J; Rinderknecht, H G; Casey, D T; Sio, H; Ruszczynski, J K; Zhou, L; Gatu Johnson, M; Frenje, J A; Séguin, F H; Li, C K; Petrasso, R D; Ruiz, C L; Leeper, R J

2012-04-01

The MIT Linear Electrostatic Ion Accelerator (LEIA) generates DD and D(3)He fusion products for the development of nuclear diagnostics for Omega, Z, and the National Ignition Facility (NIF). Significant improvements to the system in recent years are presented. Fusion reaction rates, as high as 10(7) s(-1) and 10(6) s(-1) for DD and D(3)He, respectively, are now well regulated with a new ion source and electronic gas control system. Charged fusion products are more accurately characterized, which allows for better calibration of existing nuclear diagnostics. In addition, in situ measurements of the on-target beam profile, made with a CCD camera, are used to determine the metrology of the fusion-product source for particle-counting applications. Finally, neutron diagnostics development has been facilitated by detailed Monte Carlo N-Particle Transport (MCNP) modeling of neutrons in the accelerator target chamber, which is used to correct for scattering within the system. These recent improvements have resulted in a versatile platform, which continues to support the existing nuclear diagnostics while simultaneously facilitating the development of new diagnostics in aid of the National Ignition Campaign at the National Ignition Facility. © 2012 American Institute of Physics

Upgrade of the MIT Linear Electrostatic Ion Accelerator (LEIA) for nuclear diagnostics development for Omega, Z and the NIF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinenian, N.; Manuel, M. J.-E.; Zylstra, A. B.

2012-04-15

The MIT Linear Electrostatic Ion Accelerator (LEIA) generates DD and D{sup 3}He fusion products for the development of nuclear diagnostics for Omega, Z, and the National Ignition Facility (NIF). Significant improvements to the system in recent years are presented. Fusion reaction rates, as high as 10{sup 7} s{sup -1} and 10{sup 6} s{sup -1} for DD and D{sup 3}He, respectively, are now well regulated with a new ion source and electronic gas control system. Charged fusion products are more accurately characterized, which allows for better calibration of existing nuclear diagnostics. In addition, in situ measurements of the on-target beam profile,more » made with a CCD camera, are used to determine the metrology of the fusion-product source for particle-counting applications. Finally, neutron diagnostics development has been facilitated by detailed Monte Carlo N-Particle Transport (MCNP) modeling of neutrons in the accelerator target chamber, which is used to correct for scattering within the system. These recent improvements have resulted in a versatile platform, which continues to support the existing nuclear diagnostics while simultaneously facilitating the development of new diagnostics in aid of the National Ignition Campaign at the National Ignition Facility.« less

Use of liquid metals in nuclear and thermonuclear engineering, and in other innovative technologies

NASA Astrophysics Data System (ADS)

Rachkov, V. I.; Arnol'dov, M. N.; Efanov, A. D.; Kalyakin, S. G.; Kozlov, F. A.; Loginov, N. I.; Orlov, Yu. I.; Sorokin, A. P.

2014-05-01

By now, a good deal of experience has been gained with using liquid metals as coolants in nuclear power installations; extensive knowledge has been gained about the physical, thermophysical, and physicochemical properties of these coolants; and the scientific principles and a set of methods and means for handling liquid metals as coolants for nuclear power installations have been elaborated. Prototype and commercialgrade sodium-cooled NPP power units have been developed, including the BOR-60, BN-350, and BN-600 power units (the Soviet Union); the Rapsodie, Phenix, and Superphenix power units (France), the EBR-II power unit (the United States); and the PFR power unit (the United Kingdom). In Russia, dedicated nuclear power installations have been constructed, including those with a lead-bismuth coolant for nuclear submarines and with sodium-potassium alloy for spacecraft (the Buk and Topol installations), which have no analogs around the world. Liquid metals (primarily lithium and its alloy with lead) hold promise for use in thermonuclear power engineering, where they can serve not only as a coolant, but also as tritium-producing medium. In this article, the physicochemical properties of liquid metal coolants, as well as practical experience gained from using them in nuclear and thermonuclear power engineering and in innovative technologies are considered, and the lines of further research works are formulated. New results obtained from investigations carried out on the Pb-Bi and Pb for the SVBR and BREST fast-neutron reactors (referred to henceforth as fast reactors) and for controlled accelerator systems are described.

Report of the Community Review of EIC Accelerator R&D for the Office of Nuclear Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

The Nuclear Science Advisory Committee (NSAC) of the Department of Energy (DOE) Office of Nuclear Physics (NP) recommended in the 2015 Long Range Plan (LRP) for Nuclear Science that the proposed Electron Ion Collider (EIC) be the highest priority for new construction. This report noted that, at that time, two independent designs for such a facility had evolved in the United States, each of which proposed using infrastructure already available in the U.S. nuclear science community.

Study of nuclear matter in hard proton-nuclei and nuclei-nuclei collisions at the U70 accelerator (FLUKTON project proposal)

NASA Astrophysics Data System (ADS)

Antonov, N. N.; Baldin, A. A.; Viktorov, V. A.; Gapienko, V. A.; Gapienko, G. S.; Gres, V. N.; Ilyushin, M. A.; Korotkov, V. A.; Mysnik, A. I.; Prudkoglyad, A. F.; Pryanikov, D. S.; Semak, A. A.; Stavinsky, A. V.; Terekhov, V. I.; Uglekov, V. Ya.; Ukhanov, M. N.; Chuiko, B. V.; Shimansky, S. S.

2017-11-01

A two-arm spectrometer FLUKTON for investigations in the field of relativistic nuclear physics at U70 energies is proposed to be constructed on base of the existing detector SPIN (IHEP, Protvino). The main objective is to obtain new data on clusters of cold superdense nuclear matter. Interaction of a high intensity proton beam with nuclear targets and an ion beam with liquid hydrogen and nuclear targets will be studied.

PET - radiopharmaceutical facilities at Washington University Medical School - an overview

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dence, C.S.; Welch, M.J.

1994-12-31

The PET program at Washington University has evolved over more than three decades of research and development in the use of positron-emitting isotopes in medicine and biology. In 1962 the installation of the first hospital cyclotron in the USA was accomplished. This first machine was an Allis Chalmers (AC) cyclotron and it was operated until July, 1990. Simultaneously with this cyclotron the authors also ran a Cyclotron Corporation (TCC) CS-15 cyclotron that was purchased in 1977. Both of these cyclotrons were maintained in-house and operated with a relatively small downtime (approximately 3.5%). After the dismantling of the AC machine inmore » 1990, a Japanese Steel Works 16/8 (JSW-16/8) cyclotron was installed in the vault. Whereas the AC cyclotron could only accelerate deuterons (6.2 MeV), the JSW - 16/8 machine can accelerate both protons and deuterons, so all of the radiopharmaceuticals can be produced on either of the two presently owned accelerators. At the end of May 1993, the medical school installed the first clinical Tandem Cascade Accelerator (TCA) a collaboration with Science Research Laboratories (SRL) of Somerville, MA. Preliminary target testing, design and development are presently under way. In 1973, the University installed the first operational PETT device in the country, and at present there is a large basic science and clinical research program involving more than a hundred staff in nuclear medicine, radiation sciences, neurology, neurosurgery, psychiatry, cardiology, pulmonary medicine, oncology, and surgery.« less

The ISOLDE facility and the HIE-HISOLDE project: Recent highlights

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borge, M. J. G.

2014-07-23

The ISOLDE facility at CERN has as objective the production, study and research of nuclei far from stability. The facility provides low energy radioactive beams and post-accelerated beams. In the last 45 years the ISOLDE facility has gathered unique expertise in research with radioactive beams. Over 700 isotopes of more than 70 elements have been used in a wide range of research domains, including cutting edge studies in nuclear structure, atomic physics, nuclear astrophysics, and fundamental interactions. These nuclear probes are also used to do frontier research in solid state and life sciences. There is an on-going upgrade of themore » facility, the HIE-ISOLDE project, which aims to improve the ISOLDE capabilities in a wide front, from an energy increase of the post-accelerated beam to improvements in beam quality and beam purity. The first phase of HIE-ISOLDE will start for physics in the autumn of 2015 with an upgrade of energy for all post-accelerated ISOLDE beams up to 5.5 MeV/u. In this contribution the most recent highlights of the facility are presented.« less

Negative ion source development at the cooler synchrotron COSY/Jülich

NASA Astrophysics Data System (ADS)

Felden, O.; Gebel, R.; Maier, R.; Prasuhn, D.

2013-02-01

The Nuclear Physics Institute at the Forschungszentrum Jülich, a member of the Helmholtz Association, conducts experimental and theoretical basic research in the field of hadron, particle, and nuclear physics. It operates the cooler synchrotron COSY, an accelerator and storage ring, which provides unpolarized and polarized proton and deuteron beams with beam momenta of up to 3.7 GeV/c. Main activities of the accelerator division are the design and construction of the high energy storage ring HESR, a synchrotron and part of the international FAIR project, and the operation and development of COSY with injector cyclotron and ion sources. Filament driven volume sources and a charge exchange colliding beams source, based on a nuclear polarized atomic beam source, provide unpolarized and polarized H- or D- routinely for more than 6500 hours/year. Within the Helmholtz Association's initiative Accelerator Research and Development, ARD, the existing sources at COSY, as well as new sources for future programs, are investigated and developed. The paper reports about these plans, improved pulsed beams from the volume sources and the preparation of a source for the ELENA project at CERN.

Proceedings of the 1995 Particle Accelerator Conference and international Conference on High-Energy Accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1996-01-01

Papers from the sixteenth biennial Particle Accelerator Conference, an international forum on accelerator science and technology held May 1–5, 1995, in Dallas, Texas, organized by Los Alamos National Laboratory (LANL) and Stanford Linear Accelerator Center (SLAC), jointly sponsored by the Institute of Electrical and Electronics Engineers (IEEE) Nuclear and Plasma Sciences Society (NPSS), the American Physical Society (APS) Division of Particles and Beams (DPB), and the International Union of Pure and Applied Physics (IUPAP), and conducted with support from the US Department of Energy, the National Science Foundation, and the Office of Naval Research.

The Scanning Electron Microscope As An Accelerator For The Undergraduate Advanced Physics Laboratory

NASA Astrophysics Data System (ADS)

Peterson, Randolph S.; Berggren, Karl K.; Mondol, Mark

2011-06-01

Few universities or colleges have an accelerator for use with advanced physics laboratories, but many of these institutions have a scanning electron microscope (SEM) on site, often in the biology department. As an accelerator for the undergraduate, advanced physics laboratory, the SEM is an excellent substitute for an ion accelerator. Although there are no nuclear physics experiments that can be performed with a typical 30 kV SEM, there is an opportunity for experimental work on accelerator physics, atomic physics, electron-solid interactions, and the basics of modern e-beam lithography.

Novel nuclear-cytoplasmic interaction in wheat (Triticum aestivum) induces vigorous plants

USDA-ARS?s Scientific Manuscript database

Interspecific hybridization can be considered an accelerator of evolution, otherwise a slow process, solely dependent on mutation and recombination. Upon interspecific hybridization, several novel interactions between nuclear and cytoplasmic genomes emerge which provide additional sources of diversi...

Nuclear accumulation of epidermal growth factor receptor and acceleration of G1/S stage by Epstein-Barr-encoded oncoprotein latent membrane protein 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tao Yongguang; Song Xing; Deng Xiyun

Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is considered to be the major oncogenic protein of EBV-encoded proteins and has always been the core of the oncogenic mechanism of EBV. Advanced studies on nuclear translocation of the epidermal growth factor receptor (EGFR) family have greatly improved our knowledge of the biological function of cell surface receptors. In this study, we used the Tet-on LMP1 HNE2 cell line as a cell model, which is a dual-stable LMP1-integrated nasopharyngeal carcinoma (NPC) cell line and the expression of LMP1 which could be regulated by the Tet system. We found that LMP1 couldmore » regulate the nuclear accumulation of EGFR in a dose-dependent manner quantitatively and qualitatively. We also demonstrated that the nuclear localization sequence of EGFR played some roles in the location of the protein within the nucleus under LMP1 regulation and EGFR in the nucleus could bind to the promoters of cyclinD1 and cyclinE, respectively. We further demonstrated that EGFR is involved in the acceleration of the G1/S phase transition by LMP1 through binding to cyclinD1 and cyclinE directly. These findings provided a novel view that the acceleration of LMP1 on the G1/S transition via the nuclear accumulation of EGFR was critical in the process of nasopharyngeal carcinoma.« less

Status of Environmental Management Initiatives to Accelerate the Reduction of Environmental Risks and Challenges Posed by the Legacy of the Cold War

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2009-01-01

Fifty years of nuclear weapons production and energy research in the United States during the Cold War generated large amounts of radioactive wastes, spent nuclear fuel (SNF), excess plutonium and uranium, thousands of contaminated facilities, and contaminated soil and groundwater. During most of that half century, the Nation did not have the environmental regulatory structure or nuclear waste cleanup technologies that exist today. The result was a legacy of nuclear waste that was stored and disposed of in ways now considered unacceptable. Cleaning up and ultimately disposing of these wastes is the responsibility of the U.S. Department of Energy (DOE).more » In 1989, DOE established the Office of Environmental Management (EM) to solve the large scale and technically challenging risks posed by the world's largest nuclear cleanup. This required EM to build a new nuclear cleanup infrastructure, assemble and train a technically specialized workforce, and develop the technologies and tools required to safely decontaminate, disassemble, stabilize, disposition, and remediate unique radiation hazards. The sites where nuclear activities produced legacy waste and contamination include the original Manhattan Project sites--Los Alamos, New Mexico; Hanford, Washington; and Oak Ridge, Tennessee--as well as major Cold War sites, such as Savannah River Site, South Carolina; the Idaho National Laboratory, Idaho; Rocky Flats Plant, Colorado; and Fernald, Ohio. Today EM has responsibility for nuclear cleanup activities at 21 sites covering more than two million acres in 13 states, and employs more than 30,000 Federal and contractor employees, including scientists, engineers and hazardous waste technicians. This cleanup poses unique, technically complex problems, which must be solved under the most hazardous of conditions, and which will require billions of dollars a year for several more decades. The EM program focus during its first 10 years was on managing the most urgent risks and maintaining safety at each site while negotiating state and Federal environmental compliance agreements. The program also concentrated on characterizing waste and nuclear materials and assessing the magnitude and extent of environmental contamination. By the late 1990s, EM had made significant progress in identifying and characterizing the extent of contamination and cleanup required and began transitioning from primarily a characterization and stabilization program to an active cleanup and closure program. During that time, EM formulated multi-year cleanup and closure plans, which contributed to cleanup progress; however, reducing the overall environmental risk associated with the cleanup program remained a challenge. In response, the Secretary of Energy directed a review of the EM program be undertaken. The resulting 'Top-to Bottom Review' re-directed the program focus from managing risks to accelerating the reduction of these risks.« less

Generation and application of ultrashort coherent mid-infrared electromagnetic radiation

NASA Astrophysics Data System (ADS)

Wandel, Scott

Particle accelerators are useful instruments that help address critical issues for the future development of nuclear energy. Current state-of-the-art accelerators based on conventional radio-frequency (rf) cavities are too large and expensive for widespread commercial use, and alternative designs must be considered for supplying relativistic beams to small-scale applications, including medical imaging, secu- rity screening, and scientific research in a university-scale laboratory. Laser-driven acceleration using micro-fabricated dielectric photonic structures is an attractive approach because such photonic microstructures can support accelerating fields that are 10 to 100 times higher than that of rf cavity-based accelerators. Dielectric laser accelerators (DLAs) use commercial lasers as a driving source, which are smaller and less expensive than the klystrons used to drive current rf-based accelerators. Despite the apparent need for compact and economical laser sources for laser-driven acceleration, the availability of suitable high-peak-power lasers that cover a broad spectral range is currently limited. To address the needs of several innovative acceleration mechanisms like DLA, it is proposed to develop a coherent source of mid-infrared (IR) electromagnetic radiation that can be implemented as a driving source of laser accelerators. The use of ultrashort mid-IR high peak power laser systems in various laser-driven acceleration schemes has shown the potential to greatly reduce the optical pump intensities needed to realize high acceleration gradients. The optical intensity needed to achieve a given ponderomotive potential is 25 times less when using a 5-mum mid-IR laser as compared to using a 1-mum near-IR solid-state laser. In addition, dielectric structure breakdown caused by multiphoton ionization can be avoided by using longer-wavelength driving lasers. Current mid-IR laser sources do not produce sufficiently short pulse durations, broad spectral bandwidths, or high energies as required by certain accelerator applications. The use of a high-peak-power mid-IR laser system in DLA could enable tabletop accelerators on the MeV to GeV scale for security scanners, medical therapy devices, and compact x-ray light sources. This dissertation reports on the design and construction of a simple and robust, short-pulse parametric source operating at a center wavelength of 5 mum. The design and construction of a high-energy, short-pulse 2-mum parametric source is also presented, which serves as a surrogate pumping source for the 5-mum source. An elegant method for mid-IR pulse characterization is demonstrated, which makes use of ubiquitous silicon photodetectors, traditionally reserved for the characterization of near-IR radiation. In addition, a dual-chirped parametric amplification technique is extended into the mid-IR spectral region, producing a bandwidth-tunable mid-IR source in a simple design without sacrificing conversion efficiency. The design and development of a compact single-shot mid-IR prism spectrometer is also reported, and its implementation in a number of condensed matter studies at the Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator Center is discussed. Rapid tuning and optimization of a high-energy parametric laser system using the mid-IR spectrometer is demonstrated, which significantly enhances the capabilities of performing optical measurements on superconducting materials using the LCLS instrument. All of the laser sources and optical technologies presented in this dissertation were developed using relatively simple designs to provide compact and cost-e ective systems to address some of the challenges facing accelerator and IR spectroscopy technologies. (Abstract shortened by ProQuest.).

Applications of Nuclear and Particle Physics Technology: Particles & Detection — A Brief Overview

NASA Astrophysics Data System (ADS)

Weisenberger, Andrew G.

A brief overview of the technology applications with significant societal benefit that have their origins in nuclear and particle physics research is presented. It is shown through representative examples that applications of nuclear physics can be classified into two basic areas: 1) applying the results of experimental nuclear physics and 2) applying the tools of experimental nuclear physics. Examples of the application of the tools of experimental nuclear and particle physics research are provided in the fields of accelerator and detector based technologies namely synchrotron light sources, nuclear medicine, ion implantation and radiation therapy.

Conceptual design project: Accelerator complex for nuclear physics studies and boron neutron capture therapy application at the Yerevan Physics Institute (YerPhI) Yerevan, Armenia

NASA Astrophysics Data System (ADS)

Avagyan, R. H.; Kerobyan, I. A.

2015-07-01

The final goal of the proposed project is the creation of a Complex of Accelerator Facilities at the Yerevan Physics Institute (CAF YerPhI) for nuclear physics basic researches, as well as for applied programs including boron neutron capture therapy (BNCT). The CAF will include the following facilities: Cyclotron C70, heavy material (uranium) target/ion source, mass-separator, LINAC1 (0.15-1.5 MeV/u) and LINAC2 (1.5-10 MeV/u). The delivered by C70 proton beams with energy 70 MeV will be used for investigations in the field of basic nuclear physics and with energy 30 MeV for use in applications.

Applications of Electron Linear Induction Accelerators

NASA Astrophysics Data System (ADS)

Westenskow*, Glen; Chen, Yu-Jiuan

Linear Induction Accelerators (LIAs) can readily produce intense electron beams. For example, the ATA accelerator produced a 500 GW beam and the LIU-30 a 4 TW beam (see Chap. 2). Since the induction accelerator concept was proposed in the late 1950s [1, 2], there have been many proposed schemes to convert the beam power to other forms. Categories of applications that have been demonstrated for electron LIAs include:

The CSU Accelerator and FEL Facility

NASA Astrophysics Data System (ADS)

Biedron, Sandra; Milton, Stephen; D'Audney, Alex; Edelen, Jonathan; Einstein, Josh; Harris, John; Hall, Chris; Horovitz, Kahren; Martinez, Jorge; Morin, Auralee; Sipahi, Nihan; Sipahi, Taylan; Williams, Joel

2014-03-01

The Colorado State University (CSU) Accelerator Facility will include a 6-MeV L-Band electron linear accelerator (linac) with a free-electron laser (FEL) system capable of producing Terahertz (THz) radiation, a laser laboratory, a microwave test stand, and a magnetic test stand. The photocathode drive linac will be used in conjunction with a hybrid undulator capable of producing THz radiation. Details of the systems used in CSU Accelerator Facility are discussed.

Physics division annual report 2000.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thayer, K., ed.

2001-10-04

This report summarizes the research performed in 2000 in the Physics Division of Argonne National Laboratory. The Division's programs include operation of ATLAS as a national user facility, nuclear structure and reaction research, nuclear theory and medium energy physics research, and accelerator research and development. As the Nuclear Science Advisory Committee and the nuclear science community create a new long range plan for the field in 2001, it is clear that the research of the Division is closely aligned with and continues to help define the national goals of our field. The NSAC 2001 Long Range Plan recommends as themore » highest priority for major new construction the Rare Isotope Accelerator (RIA), a bold step forward for nuclear structure and nuclear astrophysics. The accelerator R&D in the Physics Division has made major contributions to almost all aspects of the RIA design concept and the community was convinced that this project is ready to move forward. 2000 saw the end of the first Gammasphere epoch at ATLAS, One hundred Gammasphere experiments were completed between January 1998 and March 2000, 60% of which used the Fragment Mass Analyzer to provide mass identification in the reaction. The experimental program at ATLAS then shifted to other important research avenues including proton radioactivity, mass measurements with the Canadian Penning Trap and measurements of high energy gamma-rays in nuclear reactions with the MSU/ORNL/Texas A&M BaF{sub 2} array. ATLAS provided 5460 beam-research hours for user experiments and maintained an operational reliability of 95%. Radioactive beams accounted for 7% of the beam time. ATLAS also provided a crucial test of a key RIA concept, the ability to accelerate multiple charge states in a superconducting heavy-ion linac. This new capability was immediately used to increase the performance for a scheduled experiment. The medium energy program continued to make strides in examining how the quark-gluon structure of matter impacts the structure of nuclei and extended the exquisite sensitivity of the Atom-Trap-Trace-Analysis technique to new species and applications. All of this progress was built on advances in nuclear theory, which the Division pursues at the quark, hadron, and nuclear collective degrees of freedom levels. These are just a few of the highlights in the Division's research program. The results reflect the talents and dedication of the Physics Division staff and the visitors, guests and students who bring so much to the research.« less

Systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators

DOEpatents

Grisham, Larry R

2013-12-17

The present invention provides systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators. Advantageously, the systems and methods of the present invention improve the practically obtainable performance of these electrostatic accelerators by addressing, among other things, voltage holding problems and conditioning issues. The problems and issues are addressed by flowing electric currents along these accelerator electrodes to produce magnetic fields that envelope the accelerator electrodes and their support structures, so as to prevent very low energy electrons from leaving the surfaces of the accelerator electrodes and subsequently picking up energy from the surrounding electric field. In various applications, this magnetic insulation must only produce modest gains in voltage holding capability to represent a significant achievement.

Ernest Orlando Lawrence (1901-1958), Cyclotron and Medicine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chu, William T.

On August 8, 2001, Lawrence Berkeley National Laboratory celebrated the centennial of the birth of its founder (and namesake), Ernest Orlando Lawrence. For the occasion, many speeches were given and old speeches were remembered. We recall the words of the late Luis Alvarez, a Nobel Laureate and one of the Lawrence's closest colleagues: ''Lawrence will always be remembered as the inventor of the cyclotron, but more importantly, he should be remembered as the inventor of the modern way of doing science''. J. L. Heilbron and R. W. Seidel, in the introduction of their book, ''Lawrence and His Laboratory'' stated, ''Themore » motives and mechanisms that shaped the growth of the Laboratory helped to force deep changes in the scientific estate and in the wider society. In the entrepreneurship of its founder, Ernest Orlando Lawrence, these motives, mechanisms, and changes came together in a tight focus. He mobilized great and small philanthropists, state and local governments, corporations, and plutocrats, volunteers and virtuosos. The work they supported, from astrophysics and atomic bombs, from radiochemistry to nuclear medicine, shaped the way we observe, control, and manipulate our environment.'' Indeed, all over the civilized world, the ways we do science changed forever after Lawrence built his famed Radiation Laboratory. In this editorial, we epitomize his legacy of changing the way we do medicine, thereby affecting the health and well being of all humanity. This year marks the 75th anniversary of the invention of the cyclotron by Ernest Orlando Lawrence at the University of California at Berkeley. Lawrence conceived the idea of the cyclotron early in 1929 after reading an article by Rolf Wideroe on high-energy accelerators. In the spring of 1930 one of his students, Nels Edlefsen, constructed two crude models of a cyclotron. Later in the fall of the same year, another student, M. Stanley Livingston, constructed a 13-cm diameter model that had all the features of early cyclotrons, accelerating protons to 80,000 volts using less than 1,000 volts on a semi-circular accelerating electrode, now called the ''dee''. Following the discovery by J. D. Cockcroft and E. T. S. Walton of how to produce larger currents at higher voltages, Lawrence constructed the first two-dee 27-Inch (69-cm) Cyclotron, which produced protons and deuterons of 4.8 MeV. The 27-Inch Cyclotron was used extensively in early investigations of nuclear reactions involving neutrons and artificial radioactivity. In 1939, working with William Brobeck, Lawrence constructed the 60-Inch (150-cm) Cyclotron, which accelerated deuterons to 19 MeV. It was housed in the Crocker Laboratory, where scientists first made transmutations of some elements, discovered several transuranic elements, and created hundreds of radioisotopes of known elements. At the Crocker Laboratory the new medical modality called nuclear medicine was born, which used radioisotopes for diagnosis and treatment of human diseases. In 1939 Lawrence was awarded the Nobel Prize in Physics, and later element 103 was named ''Lawrencium'' in his honor.« less

Physics Division progress report for period ending September 30, 1983

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1983-12-01

Research and development activities are summarized in the following areas: Holifield Heavy Ion Research Facility, nuclear physics, the UNISOR program, accelerator-based atomic physics, theoretical physics, nuclear science applications, atomic physics and plasma diagnostics for fusion program, high-energy physics, the nuclear data project, and the relativistic heavy-ion collider study. Publications and papers presented are listed. (WHK)

Cloning of the transgenic pigs expressing human decay accelerating factor and N-acetylglucosaminyltransferase III.

PubMed

Fujimura, Tatsuya; Kurome, Mayuko; Murakami, Hiroshi; Takahagi, Yoichi; Matsunami, Katsuyoshi; Shimanuki, Shinichi; Suzuki, Kohei; Miyagawa, Shuji; Shirakura, Ryota; Shigehisa, Tamotsu; Nagashima, Hiroshi

2004-01-01

The present paper describes production of cloned pigs from fibroblast cells of transgenic pigs expressing human decay accelerating factor (DAF, CD55) and N-acetylglucosaminyltransferase III (GnT-III) that remodels sugar-chain biosynthesis. Two nuclear transfer protocols were used: a two-step activation (TA) method and a delayed activation (DA) method. Enucleated in vitro-matured oocytes and donor cells were electrically fused in a calcium-containing medium by TA method or in a calcium-free medium by DA method, followed by electrical activation 1-1.5 h later, respectively. In vitro blastocyst formation rates of nuclear transferred embryos reconstructed by TA and DA method were 8% and 14%, respectively. As a result of embryo transfer of the reconstructed embryos made by each method into recipient pigs, both gave rise to cloned piglets. These cloned pigs expressed transgene as much as their nuclear donor cells. In conclusions, (1) pig cloning can be carried out by TA or DA nuclear transfer methods, (2) expression of transgenes can be maintained to cloned pigs from the nuclear donor cells derived from transgenic animals.

Nuclear Physics Laboratory 1979 annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adelberger, E.G.

1979-07-01

Research progress is reported in the following areas: astrophysics and cosmology, fundamental symmetries, nuclear structure, radiative capture, medium energy physics, heavy ion reactions, research by users and visitors, accelerator and ion source development, instrumentation and experimental techniques, and computers and computing. Publications are listed. (WHK)

Research at the University of Kentucky Accelerator Laboratory

NASA Astrophysics Data System (ADS)

Hicks, S. F.; Kovash, M. A.

The Department of Physics and Astronomy at the University of Kentucky operates a 7-MV CN Van de Graaff accelerator that produces primary beams of protons, deuterons, and helium ions. An in-terminal pulsing and bunching system operates at 1.875 MHz and is capable of providing 1 ns beam bunches at an average current of several microamperes. Nearly all ongoing research programs involve secondary pulsed neutrons produced with gas cells containing deuterium or tritium, as well as with a variety of solid targets. Most experiments are performed at a target station positioned over a deep pit, so as to reduce the background created by backscattered neutrons. Recent experiments will be described; these include: measurements of n-p scattering total cross sections from En= 90 to 1800 keV to determine the n-p effective range parameter; the response of the plastic scintillator BC-418 below 1 MeV to low-energy recoil protons; n-p radiative capture cross sections important for our understanding of nucleosynthesis approximately 2 minutes after the occurrence of the Big Bang; γ-ray spectroscopy following inelastic neutron scattering to study nuclear structure relevant to double-β decay and to understand the role of phonon-coupled excitations in weakly deformed nuclei; and measurements of neutron elastic and inelastic scattering cross sections for nuclei that are important for energy production and for our global understanding of the interaction of neutrons with matter.

Modelling the radiolytic corrosion of α-doped UO2 and spent nuclear fuel

NASA Astrophysics Data System (ADS)

Liu, Nazhen; Qin, Zack; Noël, James J.; Shoesmith, David W.

2017-10-01

A model previously developed to predict the corrosion rate of spent fuel (UO2) inside a failed waste container has been adapted to simulate the rates measured on a wide range of α-doped UO2 and spent fuel specimens. This simulation confirms the validity of the model and demonstrates that the steady-state corrosion rate is controlled by the radiolytic production of H2O2 (which has been shown to be the primary oxidant driving fuel corrosion), irrespective of the reactivity of the UO2 matrix. The model was then used to determine the consequences of corrosion inside a failed container resealed by steel corrosion products. The possible accumulation of O2, produced by H2O2 decomposition, was found to accelerate the corrosion rate in a closed system. However, the simultaneous accumulation of radiolytic H2, which is activated as a reductant on the noble metal (ε) particles in the spent fuel, rapidly overcame this acceleration leading to the eventual suppression of the corrosion rate to insignificant values. Calculations also showed that, while the radiation dose rate, the H2O2 decomposition ratio, and the surface coverage of ε particles all influenced the short term corrosion rate, the influence of the radiolytically produced H2 was the overwhelming influence in reducing the rate to negligible level (i.e., <10-20 mol m-2 s-1).

Impedance Dynamics in the Self-Magnetic Pinch (SMP) Diode on the RITS-6 Accelerator

NASA Astrophysics Data System (ADS)

Renk, Timothy; Johnston, Mark; Leckbee, Joshua; Webb, Timothy; Mazarakis, Michael; Kiefer, Mark; Bennett, Nichelle

2014-10-01

The RITS-6 inductive voltage adder (IVA) accelerator (3.5-8.5 MeV) at Sandia National Laboratories produces high-power (TW) focused electron beams (<3 mm diameter) for flash x-ray radiography applications. The Self-Magnetic Pinch (SMP) diode utilizes a hollowed metal cathode to produce a pinched focus onto a high Z metal converter. The electron flow from the IVA driver into the load region complicates understanding of diode evolution. There is growing evidence that reducing cathode size below some ``optimum'' value in order to achieve desired spot size reduction results in pinch instabilities leading to either reduced dose-rate, early radiation power termination, or both. We are studying evolving pinch dynamics with current and x-ray monitors, optical diagnostics, and spectroscopy, as well as with LSP [1] code simulations. We are also planning changes to anode-cathode materials as well as changes to the diode aspect ratio in an attempt to mitigate the above trends and improve pinch stability while achieving simultaneous spot size reduction. Experiments are ongoing, and latest results will be reported [1]. LSP is a software product of ATK Mission Research, Albuquerque, NM. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Adminis-tration under Contract DE-AC04-94AL85000.

High-energy particles associated with solar flares

NASA Technical Reports Server (NTRS)

Sakurai, K.; Klimas, A. J.

1974-01-01

High-energy particles, the so-called solar cosmic rays, are often generated in association with solar flares, and then emitted into interplanetary space. These particles, consisting of electrons, protons, and other heavier nuclei, including the iron-group, are accelerated in the vicinity of the flare. By studying the temporal and spatial varation of these particles near the earth's orbit, their storage and release mechanisms in the solar corona and their propagation mechanism can be understood. The details of the nuclear composition and the rigidity spectrum for each nuclear component of the solar cosmic rays are important for investigating the acceleration mechanism in solar flares. The timing and efficiency of the acceleration process can also be investigated by using this information. These problems are described in some detail by using observational results on solar cosmic rays and associated phenomena.

Tandem accelerators in Romania: Multi-tools for science, education and technology

NASA Astrophysics Data System (ADS)

Burducea, I.; GhiÅ£ǎ, D. G.; Sava, T. B.; Straticiuc, M.

2017-06-01

An educated selection of the main beam parameters - particle type, velocity and intensity, can result in a cutting-edge scalpel to remove tumors, sanitize sewage, act as a nuclear forensics detective, date an artefact, clean up air, improve a microprocessor, transmute nuclear waste, detect a counterfeit or even look into the stars. Nowadays more than particle accelerators operate worldwide in medicine, industry and basic research. For example the proton therapy market is expected to attain 1 billion US per year in 2019 with almost 330 proton therapy rooms, while the annual market for the ion implantation industry already reached 1.5 G in revenue [1,2]. A brief history of the Tandem Accelerators Complex at IFIN-HH [3] emphasizing on their applications and the physics behind the scenes, is also presented [4-6].

New Concepts and Fermilab Facilities for Antimatter Research

NASA Astrophysics Data System (ADS)

Jackson, Gerald

2008-04-01

There has long been significant interest in continuing antimatter research at the Fermi National Accelerator Laboratory. Beam kinetic energies ranging from 10 GeV all the way down to the eV scale and below are of interest. There are three physics missions currently being developed: the continuation of charmonium physics utilizing an internal target; atomic physics with in-flight generated antihydrogen atoms; and deceleration to thermal energies and paasage of antiprotons through a grating system to determine their gravitation acceleration. Non-physics missions include the study of medical applications, tests of deep-space propulsion concepts, low-risk testing of nuclear fuel elements, and active interrogation for smuggled nuclear materials in support of homeland security. This paper reviews recent beam physics and accelerator technology innovations in the development of methods and new Fermilab facilities for the above missions.

Jefferson Lab 12 GEV Cebaf Upgrade

NASA Astrophysics Data System (ADS)

Rode, C. H.

2010-04-01

The existing continuous electron beam accelerator facility (CEBAF) at Thomas Jefferson National Accelerator Facility (TJNAF) is a 5-pass, recirculating cw electron Linac operating at ˜6 GeV and is devoted to basic research in nuclear physics. The 12 GeV CEBAF Upgrade is a 310 M project, sponsored by the Department of Energy (DOE) Office of Nuclear Physics, that will expand its research capabilities substantially by doubling the maximum energy and adding major new experimental apparatus. The project received construction approval in September 2008 and has started the major procurement process. The cryogenic aspects of the 12 GeV CEBAF Upgrade includes: doubling the accelerating voltages of the Linacs by adding ten new high-performance, superconducting radiofrequency (SRF) cryomodules (CMs) to the existing 42 1/4 cryomodules; doubling of the 2 K cryogenics plant; and the addition of eight superconducting magnets.

The Soreq Applied Research Accelerator Facility (SARAF): Overview, research programs and future plans

NASA Astrophysics Data System (ADS)

Mardor, Israel; Aviv, Ofer; Avrigeanu, Marilena; Berkovits, Dan; Dahan, Adi; Dickel, Timo; Eliyahu, Ilan; Gai, Moshe; Gavish-Segev, Inbal; Halfon, Shlomi; Hass, Michael; Hirsh, Tsviki; Kaiser, Boaz; Kijel, Daniel; Kreisel, Arik; Mishnayot, Yonatan; Mukul, Ish; Ohayon, Ben; Paul, Michael; Perry, Amichay; Rahangdale, Hitesh; Rodnizki, Jacob; Ron, Guy; Sasson-Zukran, Revital; Shor, Asher; Silverman, Ido; Tessler, Moshe; Vaintraub, Sergey; Weissman, Leo

2018-05-01

The Soreq Applied Research Accelerator Facility (SARAF) is under construction in the Soreq Nuclear Research Center at Yavne, Israel. When completed at the beginning of the next decade, SARAF will be a user facility for basic and applied nuclear physics, based on a 40 MeV, 5 mA CW proton/deuteron superconducting linear accelerator. Phase I of SARAF (SARAF-I, 4 MeV, 2 mA CW protons, 5 MeV 1 mA CW deuterons) is already in operation, generating scientific results in several fields of interest. The main ongoing program at SARAF-I is the production of 30 keV neutrons and measurement of Maxwellian Averaged Cross Sections (MACS), important for the astrophysical s-process. The world leading Maxwellian epithermal neutron yield at SARAF-I (5 × 10^{10} epithermal neutrons/s), generated by a novel Liquid-Lithium Target (LiLiT), enables improved precision of known MACSs, and new measurements of low-abundance and radioactive isotopes. Research plans for SARAF-II span several disciplines: precision studies of beyond-Standard-Model effects by trapping light exotic radioisotopes, such as 6He, 8Li and 18, 19, 23Ne, in unprecedented amounts (including meaningful studies already at SARAF-I); extended nuclear astrophysics research with higher energy neutrons, including generation and studies of exotic neutron-rich isotopes relevant to the rapid (r-) process; nuclear structure of exotic isotopes; high energy neutron cross sections for basic nuclear physics and material science research, including neutron induced radiation damage; neutron based imaging and therapy; and novel radiopharmaceuticals development and production. In this paper we present a technical overview of SARAF-I and II, including a description of the accelerator and its irradiation targets; a survey of existing research programs at SARAF-I; and the research potential at the completed facility (SARAF-II).

HIGH ENERGY, HIGH BRIGHTNESS X-RAYS PRODUCED BY COMPTON BACKSCATTERING AT THE LIVERMORE PLEIADES FACILITY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tremaine, A M; Anderson, S G; Betts, S

2005-05-19

PLEIADES (Picosecond Laser Electron Interaction for the Dynamic Evaluation of Structures) produces tunable 30-140 keV x-rays with 0.3-5 ps pulse lengths and up to 10{sup 7} photons/pulse by colliding a high brightness electron beam with a high power laser. The electron beam is created by an rf photo-injector system, accelerated by a 120 MeV linac, and focused to 20 {micro}m with novel permanent magnet quadrupoles. To produce Compton back scattered x-rays, the electron bunch is overlapped with a Ti:Sapphire laser that delivers 500 mJ, 100 fs, pulses to the interaction point. K-edge radiography at 115 keV on Uranium has verifiedmore » the angle correlated energy spectrum inherent in Compton scattering and high-energy tunability of the Livermore source. Current upgrades to the facility will allow laser pumping of targets synchronized to the x-ray source enabling dynamic diffraction and time-resolved studies of high Z materials. Near future plans include extending the radiation energies to >400 keV, allowing for nuclear fluorescence studies of materials.« less

Angular-momentum-assisted dissociation of CO in strong optical fields

NASA Astrophysics Data System (ADS)

Mullin, Amy; Ogden, Hannah; Murray, Matthew; Liu, Qingnan; Toro, Carlos

2017-04-01

Filaments are produced in CO gas by intense, chirped laser pulses. Visible emission from C2 is observed as a result of chemical reactions of highly excited CO. At laser intensities greater than 1014 W cm-2, the C2 emission shows a strong dependence on laser polarization. Oppositely chirped pulses of light with ω0 = 800 nm are recombined spatially and temporally to generate angularly accelerating electric fields (up to 30 THz) that either have an instantaneous linear polarization or act as a dynamic polarization grating that oscillates among linear and circular polarizations. The angularly accelerating linear polarization corresponds to an optical centrifuge that concurrently drives molecules into high rotational states (with J 50) and induces strong-field dissociation. Higher order excitation is observed for the time-varying laser polarization configuration that does not induce rotational excitation. The results indicate that the presence of rotational angular momentum lowers the threshold for CO dissociation in strong optical fields by coupling nuclear and electronic degrees of freedom. Support from NSF CHE-1058721 and the University of Maryland.

Magnetized Collisionless Shock Studies Using High Velocity Plasmoids

NASA Astrophysics Data System (ADS)

Weber, Thomas; Intrator, T.

2013-04-01

Magnetized collisionless shocks are ubiquitous throughout the cosmos and are observed to accelerate particles to relativistic velocities, amplify magnetic fields, transport energy, and create non-thermal distributions. They exhibit transitional scale lengths much shorter than the collisional mean free path and are mediated by collective interactions rather than Coulomb collisions. The Magnetized Shock Experiment (MSX) leverages advances in Field Reversed Configuration (FRC) plasmoid formation and acceleration to produce highly supersonic and super-Alfvénic supercritical shocks with pre-existing magnetic field at perpendicular, parallel or oblique angles to the direction of propagation. Adjustable shock speed, density, and magnetic field provide unique access to a range of parameter space relevant to a variety of naturally occurring shocks. This effort examines experimentally, analytically, and numerically the physics of collisionless shock formation, structure, and kinetic effects in a laboratory setting and draw comparisons between experimental data and astronomical observations. Supported by DOE Office of Fusion Energy Sciences and National Nuclear Security Administration under LANS contract DE-AC52-06NA25369 Approved for Public Release: LA-UR-12-22886

10 CFR 30.3 - Activities requiring license.

Code of Federal Regulations, 2010 CFR

2010-01-01

... that possesses and uses accelerator-produced radioactive material or discrete sources of radium-226 for...-produced radioactive material or discrete sources of radium-226 for which a specific license is required in... section, all other licensees, who possess and use accelerator-produced radioactive material or discrete...

Mass and abundance 236U sensitivities at CIRCE

NASA Astrophysics Data System (ADS)

De Cesare, M.; De Cesare, N.; D'Onofrio, A.; Fifield, L. K.; Gialanella, L.; Terrasi, F.

2015-10-01

The actinides (e.g. 236U and xPu isotopes) are present in environmental samples at the ultra trace level since atmospheric tests of NWs (Nuclear Weapons) performed in the past, deliberate dumping of nuclear waste, nuclear fuel reprocessing, on a large scale and operation of NPPs (Nuclear Power Plants) on a small scale have led to the release of a wide range of radioactive nuclides in the environment. Their detection requires the most sensitive AMS (Accelerator Mass Spectrometry) techniques and at the Center for Isotopic Research on Cultural and Environmental heritage (CIRCE) in Caserta, Italy, an upgraded actinide AMS system, based on a 3-MV pelletron tandem accelerator, has been operated. In this paper the progress made in order to push the 236U mass sensitivity and 236U/238U isotopic ratio down to the natural levels is reported. A uranium contamination mass of about 0.05 μg and a 236U/238U isotopic ratio sensitivities at the level of 3.2 × 10-13 are presently achievable.

Extreme Light Infrastructure - Nuclear Physics Eli-Np Project

NASA Astrophysics Data System (ADS)

Gales, S.

2015-06-01

The development of high power lasers and the combination of such novel devices with accelerator technology has enlarged the science reach of many research fields, in particular High energy, Nuclear and Astrophysics as well as societal applications in Material Science, Nuclear Energy and Medicine. The European Strategic Forum for Research Infrastructures (ESFRI) has selected a proposal based on these new premises called "ELI" for Extreme Light Infrastructure. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for Nuclear Physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW class lasers and a Back Compton Scattering High Brilliance and Intense Low Energy Gamma Beam , a marriage of Laser and Accelerator technology at the frontier of knowledge. In the present paper, the technical description of the facility, the present status of the project as well as the science, applications and future perspectives will be discussed.

Nuclear Science and Applications with the Next Generation of High-Power Lasers and Brilliant Low-Energy Gamma Beams at ELI-NP

NASA Astrophysics Data System (ADS)

Gales, S.; ELI-NP Team

2015-10-01

The development of high power lasers and the combination of such novel devices with accelerator technology has enlarged the science reach of many research fields, in particular High Energy, Nuclear and Astrophysics as well as societal applications in Material Science, Nuclear Energy and Medicine. The European Strategic Forum for Research Infrastructures (ESFRI) has selected a proposal based on these new premises called "ELI" for Extreme Light Infrastructure. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for Nuclear Physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW class lasers and a Back Compton Scattering High Brilliance and Intense Low Energy Gamma Beam, a marriage of Laser and Accelerator technology at the frontier of knowledge. In the present paper, the technical and scientific status of the project as well as the applications of the gamma source will be discussed.

Acceleration of electrons and ions by strong lower-hybrid turbulence in solar flares

NASA Technical Reports Server (NTRS)

Spicer, D. S.; Bingham, R.; Su, J. J.; Shapiro, V. D.; Shevchenko, V.; Ma, S.; Dawson, J. M.; Mcclements, K. G.

1994-01-01

One of the outstanding problems in solar flare theory is how to explain the 10-20 keV and greater hard x-ray emissions by a thick target bremsstrahlung model. The model requires the acceleration mechanism to accelerate approximately 10(exp 35) electrons sec(exp -l) with comparable energies, without producing a large return current which persists for long time scales after the beam ceases to exist due to Lenz's law, thereby, producing a self-magnetic field of order a few mega-Gauss. In this paper, we investigate particle acceleration resulting from the relaxation of unstable ion ring distributions, producing strong wave activity at the lower hybrid frequency. It is shown that strong lower hybrid wave turbulence collapses in configuration space producing density cavities containing intense electrostatic lower hybrid wave activity. The collapse of these intense nonlinear wave packets saturate by particle acceleration producing energetic electron and ion tails. There are several mechanisms whereby unstable ion distributions could be formed in the solar atmosphere, including reflection at perpendicular shocks, tearing modes, and loss cone depletion. Numerical simulations of ion ring relaxation processes, obtained using a 2 1/2-D fully electromagnetic, relativistic particle in cell code are discussed. We apply the results to the problem of explaining energetic particle production in solar flares. The results show the simultaneous acceleration of both electrons and ions to very high energies: electrons are accelerated to energies in the range 10-500 keV, while ions are accelerated to energies of the order of MeVs, giving rise to x-ray emission and gamma-ray emission respectively. Our simulations also show wave generation at the electron cyclotron frequency. We suggest that these waves are the solar millisecond radio spikes. The strong turbulence collapse process leads to a highly filamented plasma producing many localized regions for particle acceleration and resulting in approximately 10(exp 17) electron 'beamlets' of width approximately equal to 10 lambda sub De which eliminates the production of large magnetic fields. In this paper, we demonstrate that the model produces an energetic electron spectrum with the right flux to account for the hard x-ray observations.

GEM*STAR: Time for an Alternative Way Forward

NASA Astrophysics Data System (ADS)

Vogelaar, R. Bruce

2011-10-01

The presumption that nuclear reactors will retain their role in global energy production is constantly being challenged - even more so following recent events at Fukushima. Nuclear energy, despite being ``green,'' has inexorably been coupled in the public mind with three paramount concerns: safety, weapons proliferation, and waste (and then ultimately cost). Over the past four decades, the safety of deployed fleets has greatly improved, yet the capital and political costs of a ``nuclear energy option'' appear insurmountable in several countries. The US approach to civilian nuclear energy has become deeply entrenched, first through choices made by the military, and then by the deployed nuclear reactor fleet. This extends to the research agencies as well, to the point where basic sciences and nuclear energy operate in separate spheres. But technologies and priorities have changed, and the time has arrived where a transformative re-think of nuclear energy is not only possible, but urgent. And nuclear physicists are uniquely positioned to accomplish this. This talk will show that by asking, and answering,``what would an accelerator-driven civilian nuclear energy program look like,'' ADNA Corporation's GEM*STAR design directly addresses all three fundamental concerns: safety, proliferation, and waste - and also the final hurdle: cost. GEM*STAR is not an ``add-on'' (to either Project-X, or GEN III+), but rather a base-line energy production capacity, for either electricity or transport fuel production. It integrates and advances the molten-salt reactor technology developed at ORNL, the MW beam accelerator technologies developed by basic sciences, and a reactor/target design optimized for accelerator driven-systems. The results include: the ability to use LWR spent fuel without reprocessing or additional waste; the ability to use natural uranium; no critical mass ever present; orders-of-magnitude less volatile radioactivity in the core; more efficient use of, and deeper burn of actinides, without additional waste; proliferation resistance (no enrichment or reprocessing); high-tolerance to ``beam-trips'' and ultimately, and perhaps most importantly, lower cost electricity or diesel fuel than any currently envisioned new energy source.

Photoelectron linear accelerator for producing a low emittance polarized electron beam

DOEpatents

Yu, David U.; Clendenin, James E.; Kirby, Robert E.

2004-06-01

A photoelectron linear accelerator for producing a low emittance polarized electric beam. The accelerator includes a tube having an inner wall, the inner tube wall being coated by a getter material. A portable, or demountable, cathode plug is mounted within said tube, the surface of said cathode having a semiconductor material formed thereon.

The Creation and Destruction of Hf-178m2 Isomer by Neutron Interaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsu, Hsiao-Hua; Talbert, Willard L.; Ward, Tom

The property of the isomer state in 178m2Hf was an interesting topic in nuclear structure studies during the time period 1970 to 1980. The state at 2.446 MeV with spin and parity K π = 16 +, has a half-life of 31 years. The isomer is described as a four-quasi-particle state. The K forbidden deexcitatiion by gamma emission is the reason for long half-life. During 1980, the isomer became a troublesome issue for radiation safety workers, because this isomer can also be produced in the first wall of a fussion reactor containing tungsten and also in a tungsten beam stopmore » of a high-energy accelerator.« less

Studies on Materials for Heavy-Liquid-Metal-Cooled Reactors in Japan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minoru Takahashi; Masayuki Igashira; Toru Obara

2002-07-01

Recent studies on materials for the development of lead-bismuth (Pb-Bi)-cooled fast reactors (FR) and accelerator-driven sub-critical systems (ADS) in Japan are reported. The measurement of the neutron cross section of Bi to produce {sup 210}Po, the removal experiment of Po contamination and steel corrosion test in Pb-Bi flow were performed in Tokyo Institute of Technology. A target material corrosion test was performed in the project of Transmutation Experimental Facility for ADS in Japan Atomic Energy Research Institute (JAERI). Steel corrosion test was started in Mitsui Engineering and Shipbuilding Co., LTD (MES). The feasibility study for FR cycle performed in Japanmore » Nuclear Cycle Institute (JNC) are described. (authors)« less

Production of Ac-225 for cancer therapy by photon-induced transmutation of Ra-226.

PubMed

Melville, G; Meriarty, H; Metcalfe, P; Knittel, T; Allen, B J

2007-09-01

The increasing application of Ac-225 for cancer therapy indicates the potential need for its increased production and availability. The production of Ac-225 has been achieved using bremsstrahlung photons from an 18 MV medical linear accelerator (linac) to bombard a Ra-226 target. A linac dose of 2800 Gy produced about 64 microCi of Ra-225, which decays to Ac-225. This result, while consistent with the theoretical calculations, is far too low to be of practical use. A more powerful linac is required that runs at a higher current, longer pulse length and higher frequency for practical production. This process could also lead to the reduction of the nuclear waste product Ra-226.

Accessibility of selenomethionine proteins by total chemical synthesis: structural studies of human herpesvirus-8 MIP-II.

PubMed

Shao, W; Fernandez, E; Wilken, J; Thompson, D A; Siani, M A; West, J; Lolis, E; Schweitzer, B I

1998-12-11

The determination of high resolution three-dimensional structures by X-ray crystallography or nuclear magnetic resonance (NMR) is a time-consuming process. Here we describe an approach to circumvent the cloning and expression of a recombinant protein as well as screening for heavy atom derivatives. The selenomethionine-modified chemokine macrophage inflammatory protein-II (MIP-II) from human herpesvirus-8 has been produced by total chemical synthesis, crystallized, and characterized by NMR. The protein has a secondary structure typical of other chemokines and forms a monomer in solution. These results indicate that total chemical synthesis can be used to accelerate the determination of three-dimensional structures of new proteins identified in genome programs.

Knockout and fragmentation reactions using a broad range of tin isotopes

NASA Astrophysics Data System (ADS)

Rodríguez-Sánchez, J. L.; Benlliure, J.; Bertulani, C. A.; Vargas, J.; Ayyad, Y.; Alvarez-Pol, H.; Atkinson, J.; Aumann, T.; Beceiro-Novo, S.; Boretzky, K.; Caamaño, M.; Casarejos, E.; Cortina-Gil, D.; Díaz-Cortes, J.; Fernández, P. Díaz; Estrade, A.; Geissel, H.; Kelić-Heil, A.; Litvinov, Yu. A.; Mostazo, M.; Paradela, C.; Pérez-Loureiro, D.; Pietri, S.; Prochazka, A.; Takechi, M.; Weick, H.; Winfield, J. S.

2017-09-01

Production cross sections of residual nuclei obtained by knockout and fragmentation reactions of different tin isotopes accelerated at 1 A GeV have been measured with the fragment separator (FRS) at GSI, Darmstadt. The new measurements are used to investigate the neutron-excess dependence of the neutron- and proton-knockout cross sections. These cross sections are compared to Glauber model calculations coupled to a nuclear de-excitation code in order to investigate the role of the remnant excitations. This bench marking shows an overestimation of the cross sections for the removal of deeply bound nucleons. A phenomenological increase in the excitation energy induced in the remnants produced in these cases allows us to reproduce the measured cross sections.

Wind Power Now!

ERIC Educational Resources Information Center

Inglis, David Rittenhouse

1975-01-01

The government promotes and heavily subsidizes research in nuclear power plants. Federal development of wind power is slow in comparison even though much research with large wind-electric machines has already been conducted. Unless wind power programs are accelerated it will not become a major energy alternative to nuclear power. (MR)

Photonuclear-based, nuclear material detection system for cargo containers

NASA Astrophysics Data System (ADS)

Jones, J. L.; Yoon, W. Y.; Norman, D. R.; Haskell, K. J.; Zabriskie, J. M.; Watson, S. M.; Sterbentz, J. W.

2005-12-01

The Idaho National Laboratory (INL) has been developing electron accelerator-based, photonuclear inspection technologies for over a decade. A current need, having important national implications, has been with the detection of smuggled nuclear material within air- and, especially, sea-cargo transportation containers. This paper describes the latest pulsed, photonuclear inspection system for nuclear material detection and identification in cargo configurations, the numerical responses of 5 kg of a nuclear material placed within selected cargo configurations, and the technology's potential role in addressing future inspection needs.

Ion beams 12, Legnaro 6-8 June 2012, the 50 years (1961-2011) of the Legnaro Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ricci, Renato Angelo

2013-07-18

A short review of the history of the Legnaro Laboratory is presented since its foundation 50 years ago by Prof. A. Rostagni of the University of Padova. The evolution of the Laboratory as a national reference center for fundamental and applied nuclear physics researches is outlined, pointing out its transformation into the INFN National Laboratories in 1968. After the first CN VdG Accelerator of 5.5 MV operating in 1961 and the AN2000 devoted to interdisciplinary researches (1971), i.e. 40 years ago, ten years later the advent of the first heavy ion facility in Italy, the XTU Tandem accelerator, and latermore » on of the ALPI superconducting linear accelerator, was crucial for any future developments, not only in the field of nuclear physics but also for the evolution of interdisciplinary programmes with ion beams.« less

Preliminary Results from Pyroelectric Crystal Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Tom; Edwards, Ronald; Bright, Kevin

The Nuclear Science and Engineering Research Center (NSERC), a Defense Threat Reduction Agency (DTRA) office located at the United States Military Academy (USMA), sponsors and manages cadet and faculty research in support of DTRA objectives. Cadets in the Department of Physics and Nuclear Engineering at USMA are using pyroelectric crystals to ionize and accelerate residual gas trapped inside a vacuum system. A system using two lithium tantalate crystals with associated diagnostics was designed and is now operational. X-ray energies of approximately 150 keV have been achieved. Future work will focus on developing a portable neutron generator using the D-D nuclearmore » fusion process.« less

Effect of buoyancy on fuel containment in an open-cycle gas-core nuclear rocket engine.

NASA Technical Reports Server (NTRS)

Putre, H. A.

1971-01-01

Analysis aimed at determining the scaling laws for the buoyancy effect on fuel containment in an open-cycle gas-core nuclear rocket engine, so conducted that experimental conditions can be related to engine conditions. The fuel volume fraction in a short coaxial flow cavity is calculated with a programmed numerical solution of the steady Navier-Stokes equations for isothermal, variable density fluid mixing. A dimensionless parameter B, called the Buoyancy number, was found to correlate the fuel volume fraction for large accelerations and various density ratios. This parameter has the value B = 0 for zero acceleration, and B = 350 for typical engine conditions.

Medical Applications at CERN and the ENLIGHT Network

PubMed Central

Dosanjh, Manjit; Cirilli, Manuela; Myers, Steve; Navin, Sparsh

2016-01-01

State-of-the-art techniques derived from particle accelerators, detectors, and physics computing are routinely used in clinical practice and medical research centers: from imaging technologies to dedicated accelerators for cancer therapy and nuclear medicine, simulations, and data analytics. Principles of particle physics themselves are the foundation of a cutting edge radiotherapy technique for cancer treatment: hadron therapy. This article is an overview of the involvement of CERN, the European Organization for Nuclear Research, in medical applications, with specific focus on hadron therapy. It also presents the history, achievements, and future scientific goals of the European Network for Light Ion Hadron Therapy, whose co-ordination office is at CERN. PMID:26835422

Medical Applications at CERN and the ENLIGHT Network.

PubMed

Dosanjh, Manjit; Cirilli, Manuela; Myers, Steve; Navin, Sparsh

2016-01-01

State-of-the-art techniques derived from particle accelerators, detectors, and physics computing are routinely used in clinical practice and medical research centers: from imaging technologies to dedicated accelerators for cancer therapy and nuclear medicine, simulations, and data analytics. Principles of particle physics themselves are the foundation of a cutting edge radiotherapy technique for cancer treatment: hadron therapy. This article is an overview of the involvement of CERN, the European Organization for Nuclear Research, in medical applications, with specific focus on hadron therapy. It also presents the history, achievements, and future scientific goals of the European Network for Light Ion Hadron Therapy, whose co-ordination office is at CERN.

Microwave accelerator E-beam pumped laser

DOEpatents

Brau, Charles A.; Stein, William E.; Rockwood, Stephen D.

1980-01-01

A device and method for pumping gaseous lasers by means of a microwave accelerator. The microwave accelerator produces a relativistic electron beam which is applied along the longitudinal axis of the laser through an electron beam window. The incident points of the electron beam on the electron beam window are varied by deflection coils to enhance the cooling characteristics of the foil. A thyratron is used to reliably modulate the microwave accelerator to produce electron beam pulses which excite the laser medium to produce laser pulse repetition frequencies not previously obtainable. An aerodynamic window is also disclosed which eliminates foil heating problems, as well as a magnetic bottle for reducing laser cavity length and pressures while maintaining efficient energy deposition.

Initial Human Response to Nuclear Radiation

DTIC Science & Technology

1982-04-01

radiation from a linear accelerator . Victim A , age 31, received a dose of 100 rads; victim B, age 29... The radiation has always been in the million-electron- volt range, usually from a cobalt 60 source but sometimes using linear accelerators prouucing up...more recent medical experience, Appendix B presents comments by a radiation oncologist on the

Operational and design aspects of accelerators for medical applications

NASA Astrophysics Data System (ADS)

Schippers, Jacobus Maarten; Seidel, Mike

2015-03-01

Originally, the typical particle accelerators as well as their associated beam transport equipment were designed for particle and nuclear physics research and applications in isotope production. In the past few decades, such accelerators and related equipment have also been applied for medical use. This can be in the original physics laboratory environment, but for the past 20 years also in hospital-based or purely clinical environments for particle therapy. The most important specific requirements of accelerators for radiation therapy with protons or ions will be discussed. The focus will be on accelerator design, operational, and formal aspects. We will discuss the special requirements to reach a high reliability for patient treatments as well as an accurate delivery of the dose at the correct position in the patient using modern techniques like pencil beam scanning. It will be shown that the technical requirements, safety aspects, and required reliability of the accelerated beam differ substantially from those in a nuclear physics laboratory. It will be shown that this difference has significant implications on the safety and interlock systems. The operation of such a medical facility should be possible by nonaccelerator specialists at different operating sites (treatment rooms). The organization and role of the control and interlock systems can be considered as being the most crucially important issue, and therefore a special, dedicated design is absolutely necessary in a facility providing particle therapy.

A retrospective of the career of Ray Herb

NASA Astrophysics Data System (ADS)

Norton, G. A.; Ferry, J. A.; Daniel, R. E.; Klody, G. M.

1999-04-01

Ray Herb's career in the development of electrostatic accelerators spans 65 years. He began in 1933 by pressurizing a Van de Graaff generator, for the first time. Over the next six years, the group at the University of Wisconsin, under his direction, developed the fundamentals of equipotential rings, potential grading, corona triode control, and other basic mechanisms for the practical use of electrostatic accelerators while making fundamental contributions to experimental nuclear physics. This group held the world's record in sustaining potential difference of 4.5 MV. During World War II, he worked on radar at the Radiation Laboratory. After the war, Herb resumed his career with further fundamental contributions including metal/ceramic bonding, ultrahigh vacuum pumping, negative ion source development and metal charge carriers. The company, National Electrostatics, under his direction manufactured the accelerator which still holds the world's record for the highest sustained potential difference of 32±1.5 MV. Throughout his career he led teams which made the electrostatic accelerator a valuable tool for applications in a wide variety of scientific fields, well beyond nuclear physics.

The progress about measurements of the proton beam characteristics of the JUNA 400 kV accelerator

NASA Astrophysics Data System (ADS)

Wang, Shuo; Li, Kuoang

2018-04-01

China JinPing underground Laboratory (CJPL) was established inside the tunnels piercing Jinping Mountain in Sichuan Province, China, which can provide an ideal environment for low background experiment. Jinping Underground laboratory for Nuclear Astrophysics (JUNA) is one of the major research programs in CJPL. A new 400 kV accelerator, with high current based on an ECR source, will be installed into CJPL for the study of key nuclear reactions in astrophysics. The beam characteristics of the accelerator, like absolute energy, energy spread, and long-term energy stability, will be determined by several well-known resonance and non-resonance reactions. Due to the new accelerator still being under construction, the resonance reaction of 27Al(p, γ)28Si and non-resonance 12C(p, γ)13N were studied at the 320 kV high-voltage platform of Institute of Modern Physics in Lanzhou, China. The energy spread of proton beam is about 1.0 keV and the long-term energy stability of proton beam is better than ±200eV during 4 hours measurement.

Nuclear Resonance Fluorescence off 54Cr: The Onset of the Pygmy Dipole Resonance

NASA Astrophysics Data System (ADS)

Ries, P. C.; Beck, T.; Beller, J.; Krishichayan; Gayer, U.; Isaak, J.; Löher, B.; Mertes, L.; Pai, H.; Pietralla, N.; Romig, C.; Savran, D.; Schilling, M.; Tornow, W.; Werner, V.; Zweidinger, M.

2016-06-01

Low-lying electric and magnetic dipole excitations (E1 and M1) below the neutron separation threshold, particularly the Pygmy Dipole Resonance (PDR), have drawn considerable attention in the last years. So far, mostly moderately heavy nuclei in the mass regions around A = 90 and A = 140 were examined with respect to the PDR. In the present work, the systematics of the PDR have been extended by measuring excitation strengths and parity quantum numbers of J = 1 states in lighter nuclei near A = 50 in order to gather information on the onset of the PDR. The nuclei 50,52,54Cr and 48,50Ti were examined via bremsstrahlung produced at the DArmstadt Superconducting electron Linear Accelerator (S-DALINAC) with photon energies up to 9.7 MeV with the method of nuclear resonance fluorescence. Numerous excited states were observed, many of which for the first time. The parity quantum numbers of these states have been determined at the High Intensity Gamma-ray Source (HIγS) of the Triangle Universities Nuclear Laboratory in Durham, NC, USA. Informations to the methods and the experimental setups will be provided and the results on 54Cr achieved will be discussed with respect to the onset of the PDR.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-12-01

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

Measurements and PHITS Monte Carlo Estimations of Residual Activities Induced by the 181 MeV Proton Beam in the Injection Area at J-PARC RCS Ring

NASA Astrophysics Data System (ADS)

Yamakawa, Emi; Yoshimoto, Masahiro; Kinsho, Michikazu

At the injection area of the RCS ring in the J-PARC, residual gamma dose at the rectangular ceramic ducts, especially immediately downstream of the charge-exchanged foil, has increased with the output beam power. In order to investigate the cause of high residual activities, residual gamma dose and radioactive sources produced at the exterior surface of the ducts have been measured by a GM survey meter and a handy type of Germanium (Ge) semiconductor detector in the case of 181 MeV injected proton beam energy. With these measurements, it is revealed that the radioactive sources produced by nuclear reactions cause the high activities at the injection area. For a better understanding of phenomena in the injection area, various simulations have been done with the PHITS Monte Carlo code. The distribution of radioactive sources and residual gamma dose rate obtained by the calculations are consistent with the measurement results. With this consistency, secondary neutrons and protons derived from nuclear reactions at the charge-exchanged foil are the dominant cause to high residual gamma dose at the ceramic ducts in the injection area. These measurements and calculations are unique approaches to reveal the cause of high residual dose around the foil. This study is essential for the future of high-intensity proton accelerators using a stripping foil.

Benchmark Studies of the Effectiveness of Structural and Internal Materials as Radiation Shielding for the International Space Station

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, J.; Zeitlin, C.; Cucinotta, F.A.

2002-05-09

Accelerator-based measurements and model calculations have been used to study the heavy ion radiation transport properties of materials in use on the International Space Station (ISS). Samples of the ISS aluminum outer hull were augmented with various configurations of internal wall material and polyethylene. The materials were bombarded with high energy Fe ions characteristic of a significant part of the Galactic Cosmic Ray (GCR) heavy ion spectrum. Transmitted primary ions and charged fragments produced in nuclear collisions in the materials were measured near the beam axis, and a model was used to extrapolate from the data to lower beam energiesmore » and to a lighter ion. For the materials and ions studied, at incident particle energies from 1037 MeV/nucleon down to at least 600 MeV/nucleon, nuclear fragmentation reduces the average dose and dose equivalent per incident ion. At energies below 400 MeV/nucleon, the calculation predicts that as material is added, increased ionization energy loss produces increases in some dosimetric quantities. These limited results suggest that the addition of modest amounts of polyethylene or similar material to the interior of the ISS will reduce the dose to ISS crews from space radiation; however the radiation transport properties of ISS materials should be evaluated with a realistic space radiation field.« less

Benchmark studies of the effectiveness of structural and internal materials as radiation shielding for the international space station.

PubMed

Miller, J; Zeitlin, C; Cucinotta, F A; Heilbronn, L; Stephens, D; Wilson, J W

2003-03-01

Accelerator-based measurements and model calculations have been used to study the heavy-ion radiation transport properties of materials in use on the International Space Station (ISS). Samples of the ISS aluminum outer hull were augmented with various configurations of internal wall material and polyethylene. The materials were bombarded with high-energy iron ions characteristic of a significant part of the galactic cosmic-ray (GCR) heavy-ion spectrum. Transmitted primary ions and charged fragments produced in nuclear collisions in the materials were measured near the beam axis, and a model was used to extrapolate from the data to lower beam energies and to a lighter ion. For the materials and ions studied, at incident particle energies from 1037 MeV/nucleon down to at least 600 MeV/nucleon, nuclear fragmentation reduces the average dose and dose equivalent per incident ion. At energies below 400 MeV/nucleon, the calculation predicts that as material is added, increased ionization energy loss produces increases in some dosimetric quantities. These limited results suggest that the addition of modest amounts of polyethylene or similar material to the interior of the ISS will reduce the dose to ISS crews from space radiation; however, the radiation transport properties of ISS materials should be evaluated with a realistic space radiation field. Copyright 2003 by Radiation Research Society

Present status of Accelerator-Based BNCT

PubMed Central

Kreiner, Andres Juan; Bergueiro, Javier; Cartelli, Daniel; Baldo, Matias; Castell, Walter; Asoia, Javier Gomez; Padulo, Javier; Suárez Sandín, Juan Carlos; Igarzabal, Marcelo; Erhardt, Julian; Mercuri, Daniel; Valda, Alejandro A.; Minsky, Daniel M.; Debray, Mario E.; Somacal, Hector R.; Capoulat, María Eugenia; Herrera, María S.; del Grosso, Mariela F.; Gagetti, Leonardo; Anzorena, Manuel Suarez; Canepa, Nicolas; Real, Nicolas; Gun, Marcelo; Tacca, Hernán

2016-01-01

Aim This work aims at giving an updated report of the worldwide status of Accelerator-Based BNCT (AB-BNCT). Background There is a generalized perception that the availability of accelerators installed in hospitals, as neutron sources, may be crucial for the advancement of BNCT. Accordingly, in recent years a significant effort has started to develop such machines. Materials and methods A variety of possible charged-particle induced nuclear reactions and the characteristics of the resulting neutron spectra are discussed along with the worldwide activity in suitable accelerator development. Results Endothermic 7Li(p,n)7Be and 9Be(p,n)9B and exothermic 9Be(d,n)10B are compared. In addition to having much better thermo-mechanical properties than Li, Be as a target leads to stable products. This is a significant advantage for a hospital-based facility. 9Be(p,n)9B needs at least 4–5 MeV bombarding energy to have a sufficient yield, while 9Be(d,n)10B can be utilized at about 1.4 MeV, implying the smallest possible accelerator. This reaction operating with a thin target can produce a sufficiently soft spectrum to be viable for AB-BNCT. The machines considered are electrostatic single ended or tandem accelerators or radiofrequency quadrupoles plus drift tube Linacs. Conclusions 7Li(p,n)7Be provides one of the best solutions for the production of epithermal neutron beams for deep-seated tumors. However, a Li-based target poses significant technological challenges. Hence, Be has been considered as an alternative target, both in combination with (p,n) and (d,n) reactions. 9Be(d,n)10B at 1.4 MeV, with a thin target has been shown to be a realistic option for the treatment of deep-seated lesions. PMID:26933390

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

NASA Astrophysics Data System (ADS)

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.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stelson, P.H.

The bulk of the Division's effort concerned nuclear physics and accelerator development, but work in the areas of nuclear data, research applicable to the magnetic fusion project, atomic and molecular physics, and high-energy physics is also recounted. Lists of publications, technical talks, personnel, etc., are included. Individual reports with sufficient data are abstracted separately. (RWR)

The SPES High Power ISOL production target

NASA Astrophysics Data System (ADS)

Andrighetto, A.; Corradetti, S.; Ballan, M.; Borgna, F.; Manzolaro, M.; Scarpa, D.; Monetti, A.; Rossignoli, M.; Silingardi, R.; Mozzi, A.; Vivian, G.; Boratto, E.; De Ruvo, L.; Sattin, N.; Meneghetti, G.; Oboe, R.; Guerzoni, M.; Margotti, A.; Ferrari, M.; Zenoni, A.; Prete, G.

2016-11-01

SPES (Selective Production of Exotic Species) is a facility under construction at INFN-LNL (Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Legnaro), aimed to produce intense neutron-rich radioactive ion beams (RIBs). These will be obtained using the ISOL (Isotope Separation On-Line) method, bombarding a uranium carbide target with a proton beam of 40MeV energy and currents up to 200μA. The target configuration was designed to obtain a high number of fissions, up to 1013 per second, low power deposition and fast release of the produced isotopes. The exotic isotopes generated in the target are ionized, mass separated and re-accelerated by the ALPI superconducting LINAC at energies of 10AMeV and higher, for masses in the region of A = 130 amu , with an expected rate on the secondary target up to 109 particles per second. In this work, recent results on the R&D activities regarding the SPES RIB production target-ion source system are reported.

Inspection of 56Fe γ-Ray angular distributions as a function of incident neutron energy using optical model approaches

NASA Astrophysics Data System (ADS)

Vanhoy, J. R.; Ramirez, A. P.; Alcorn-Dominguez, D. K.; Hicks, S. F.; Peters, E. E.; McEllistrem, M. T.; Mukhopadhyay, S.; Yates, S. W.

2017-09-01

Neutron inelastic scattering cross sections measured directly through (n,n) or deduced from γ-ray production cross sections following inelastic neutron scattering (n,n'γ) are a focus of basic and applied research at the University of Kentucky Accelerator Laboratory (www.pa.uky.edu/accelerator). For nuclear data applications, angle-integrated cross sections are desired over a wide range of fast neutron energies. Several days of experimental beam time are required for a data set at each incident neutron energy, which limits the number of angular distributions that can be measured in a reasonable amount of time. Approximations can be employed to generate cross sections with a higher energy resolution, since at 125o, the a2P2 term of the Legendre expansion is identically zero and the a4P4 is assumed to be very small. Provided this assumption is true, a single measurement at 125o would produce the γ-ray production cross section. This project tests these assumptions and energy dependences using the codes CINDY/SCAT and TALYS/ECIS06/SCAT. It is found that care must be taken when interpreting γ-ray excitation functions as cross sections when the incident neutron energy is < 1000 keV above threshold or before the onset of feeding.

A Truncated Nuclear Norm Regularization Method Based on Weighted Residual Error for Matrix Completion.

PubMed

Qing Liu; Zhihui Lai; Zongwei Zhou; Fangjun Kuang; Zhong Jin

2016-01-01

Low-rank matrix completion aims to recover a matrix from a small subset of its entries and has received much attention in the field of computer vision. Most existing methods formulate the task as a low-rank matrix approximation problem. A truncated nuclear norm has recently been proposed as a better approximation to the rank of matrix than a nuclear norm. The corresponding optimization method, truncated nuclear norm regularization (TNNR), converges better than the nuclear norm minimization-based methods. However, it is not robust to the number of subtracted singular values and requires a large number of iterations to converge. In this paper, a TNNR method based on weighted residual error (TNNR-WRE) for matrix completion and its extension model (ETNNR-WRE) are proposed. TNNR-WRE assigns different weights to the rows of the residual error matrix in an augmented Lagrange function to accelerate the convergence of the TNNR method. The ETNNR-WRE is much more robust to the number of subtracted singular values than the TNNR-WRE, TNNR alternating direction method of multipliers, and TNNR accelerated proximal gradient with Line search methods. Experimental results using both synthetic and real visual data sets show that the proposed TNNR-WRE and ETNNR-WRE methods perform better than TNNR and Iteratively Reweighted Nuclear Norm (IRNN) methods.

NACA Researcher Examines the Cyclotron

NASA Image and Video Library

1951-02-21

Researcher James Blue examines the new cyclotron at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory. Researchers at NACA Lewis began postulating about the use of atomic power for propulsion immediately after World War II. The NACA concentrated its efforts on the study of high temperature materials and heat transfer since it did not have access to the top secret fission information. The military studied the plausibility of nuclear propulsion for aircraft in the late 1940s. The military program was cancelled after four years without any breakthroughs, but the Atomic Energy Commission took on the effort in 1951. The NACA Lewis laboratory was expanding its nuclear-related research during this period. In 1948, Lewis engineers were assigned to the Oak Ridge National Laboratory to obtain expertise in high temperature heat transfer and advanced materials technology. The following year a new 80-person Nuclear Reactor Division was created, and an in-house nuclear school was established to train these researchers. The cyclotron was built behind the Materials and Structures Laboratory to support thermodynamic and materials research for both nuclear aircraft and nuclear rockets. The original NACA Lewis cyclotron was used to accelerate two kinds of particles. To better match the space radiation environment, the cyclotron was later modified to accelerate particles of the newly-discovered Van Allen radiation belts.

Cell Cycle Regulates Nuclear Stability of AID and Determines the Cellular Response to AID

PubMed Central

Le, Quy; Maizels, Nancy

2015-01-01

AID (Activation Induced Deaminase) deaminates cytosines in DNA to initiate immunoglobulin gene diversification and to reprogram CpG methylation in early development. AID is potentially highly mutagenic, and it causes genomic instability evident as translocations in B cell malignancies. Here we show that AID is cell cycle regulated. By high content screening microscopy, we demonstrate that AID undergoes nuclear degradation more slowly in G1 phase than in S or G2-M phase, and that mutations that affect regulatory phosphorylation or catalytic activity can alter AID stability and abundance. We directly test the role of cell cycle regulation by fusing AID to tags that destabilize nuclear protein outside of G1 or S-G2/M phases. We show that enforced nuclear localization of AID in G1 phase accelerates somatic hypermutation and class switch recombination, and is well-tolerated; while nuclear AID compromises viability in S-G2/M phase cells. We identify AID derivatives that accelerate somatic hypermutation with minimal impact on viability, which will be useful tools for engineering genes and proteins by iterative mutagenesis and selection. Our results further suggest that use of cell cycle tags to regulate nuclear stability may be generally applicable to studying DNA repair and to engineering the genome. PMID:26355458

Neutron Source from Laser Plasma Acceleration

NASA Astrophysics Data System (ADS)

Jiao, Xuejing; Shaw, Joseph; McCary, Eddie; Downer, Mike; Hegelich, Bjorn

2016-10-01

Laser driven electron beams and ion beams were utilized to produce neutron sources via different mechanism. On the Texas Petawatt laser, deuterized plastic, gold and DLC foil targets of varying thickness were shot with 150 J , 150 fs laser pulses at a peak intensity of 2 ×1021W /cm2 . Ions were accelerated by either target normal sheath acceleration or Breakout Afterburner acceleration. Neutrons were produced via the 9Be(d,n) and 9Be(p,n) reactions when accelerated ions impinged on a Beryllium converter as well as by deuteron breakup reactions. We observed 2 ×1010 neutron per shot in average, corresponding to 5 ×1018n /s . The efficiencies for different targets are comparable. In another experiment, 38fs , 0.3 J UT3 laser pulse interacted with mixed gas target. Electrons with energy 40MeV were produced via laser wakefield acceleration. Neutron flux of 2 ×106 per shot was generated through bremsstrahlung and subsequent photoneutron reactions on a Copper converter.

The nuclear accumulation of alpha-synuclein is mediated by importin alpha and promotes neurotoxicity by accelerating the cell cycle.

PubMed

Ma, Kai-Li; Song, Lian-Kun; Yuan, Yu-He; Zhang, Ying; Han, Ning; Gao, Kai; Chen, Nai-Hong

2014-07-01

α-Synuclein (α-syn), a 14 kDa pre-synaptic protein, is widely involved in the Parkinson's disease (PD) pathogenesis. Recent studies have shown that the nuclear accumulation of α-syn might have a toxic effect. The main purpose of the present study was to explore which amino acid residues in α-syn are associated with its nuclear accumulation, the molecule(s) mediated the nuclear import of α-syn, and the role of α-syn accumulated in the nucleus. It has been noted that the nuclear import of α-syn may be mediated by importin α and that both the amino acid residues 1-60 and 103-140 of α-syn were indispensable for its nuclear import. After imported into the nucleus, the accumulated α-syn played a toxic role in both the PC12 cells and the C57 mice. Furthermore, α-syn-nuclear localization signal-injected mice showed behavioral symptoms associated with PD. Further studies performed in vitro showed that the toxicity of α-syn in the nucleus might be due to an interference of the cell cycle. Thus, it can be concluded that α-syn can accumulate in nucleus, which is mediated by importin α, and promote neurotoxicity by accelerating the cell cycle. Copyright © 2013 Elsevier Ltd. All rights reserved.

Accelerator mass spectrometry of iodine-129 and its applications in natural water systems

NASA Astrophysics Data System (ADS)

Buraglio, Nadia

During recent decades, huge amount of radioactive waste has been dumped into the earth's surface environments. 129I (T1/2 = 15.6 My) is one of the radioactive products that has been produced through a variety of processes, including atomic weapon testing, reprocessing of nuclear fact and nuclear accidents. This thesis describes development of the Accelerator Mass Spectrometry (AMS) ultra-sensitive atom counting technique at Uppsala Tandem Laboratory to measure 129I and discusses investigations of its distribution in the hydrosphere (marine and fresh water) and precipitation. The AMS technique provides a method for measuring long-lived radioactive isotopes in small samples, relative to other conventional techniques, and thus opens a now line of research. The optimization of the AMS system at Uppsala included testing a time of flight detector, evaluation of the most appropriate charge-state, reduction of molecular interference and improvement of the detection limit. Furthermore, development of a chemical procedure for separation of iodine from natural water samples has been accomplished. The second part of the thesis reports investigations of 129I in natural waters and indicates that high concentrations of 129I (3-4 orders of magnitude higher than in the prenuclear era) are found in most of the considered natural waters. Inventory calculations and results of measurements suggest that the major sources of radioactive iodine are the two main European nuclear reprocessing facilities at Sellafield (U.K.) and La Hague (France). This information provides estimates of the transit time and vertical mixing of water masses in the central Arctic Ocean. Results from precipitation, lakes and runoff are used to elucidate mechanisms of transport of 129I from the point sources and its pathways in the hydrological environment. This study also shows the need for continuous monitoring of the 129I level in the hydrosphere and of its future variability.

Neutron irradiation and damage assessment of plastic scintillators of the Tile Calorimeter

NASA Astrophysics Data System (ADS)

Mdhluli, J. E.; Mellado, B.; Sideras-Haddad, E.

2017-01-01

Following the comparative study of proton induced radiation damage on various plastic scintillator samples from the ATLAS-CERN detector, a study on neutron irradiation and damage assessment on the same type of samples will be conducted. The samples will be irradiated with different dose rates of neutrons produced in favourable nuclear reactions using a radiofrequency linear particle accelerator as well as from the SAFARI nuclear reactor at NECSA. The MCNP 5 code will be utilized in simulating the neutron transport for determining the dose rate. Light transmission and light yield tests will be performed in order to assess the radiation damage on the scintillators. In addition, Raman spectroscopy and Electron Paramagnetic Resonance (EPR) analysis will be used to characterize the samples after irradiation. The project aims to extent these studies to include radiation assessment damage of any component that processes the scintillating light and deteriorates the quantum efficiency of the Tilecal detector, namely, photomultiplier tubes, wavelength shifting optical fibres and the readout electronics. They will also be exposed to neutron irradiation and the damage assessed in the same manner.

Commercial users panel

NASA Technical Reports Server (NTRS)

Byrd, Joseph S.; Flatau, Carl; Hodge, David C.; Hollis, Ralph; Leach, Eugene F.; Gilbert, Ray; Cleland, John; Leifer, Larry; Naser, Joseph; Schmuter, Samson D.

1987-01-01

The discussions of motives and requirements for telerobotics application demonstrated that, in many cases, lack of progress was a result not of limited opportunities but of inadequate mechanisms and resources for promoting opportunities. Support for this conclusion came from Telerobotics, Inc., one of the few companies devoted primarily to telerobot systems. They have produced units for such diverse applications as nuclear fusion research, particle accelerators, cryogenics, firefighting, marine biology/undersea systems and nuclear mobile robotics. Mr. Flatau offered evidence that telerobotics research is only rarely supported by the private sector and that it often presents a difficult market. Questions on the mechanisms contained within the NASA technology transfer process for promoting commercial opportunities were fielded by Ray Gilbert and Tom Walters. A few points deserve emphasis: (1) NASA/industry technology transfer occurs in both directions and NASA recognizes the opportunity to learn a great deal from industry in the fields of automation and robotics; (2) promotion of technology transfer projects takes a demand side approach, with requests to industry for specific problem identification. NASA then proposes possible solutions; and (3) comittment ofmotivated and technically qualified people on each end of a technology transfer is essential.

Towards the measurement of the13C(d, p)14C cross section using AMS

NASA Astrophysics Data System (ADS)

Murillo-Morales, S.; Barrón-Palos, L.; Chávez, E.; Araujo-Escalona, V.

2017-07-01

A plan to study the total cross section for the13C(d, p)14C nuclear reaction has been developed for energies in the center-of-mass frame between 133 and 400 keV. The proposed experiment will use a deuterium beam (1-3 MeV of energy) from the Instituto de Física-UNAM 5.5 MV Van de Graaff accelerator and the produced14C will be afterwards measured by AMS technique in the LEMA-UNAM (HVEE 1 MV Tandetron). One of the main goals is to study the performance of the LEMA-UNAM facility in the cross section measurement in comparison with other data reported in the literature, measured by other techniques. In this work we present the current status of these studies. The relevance of the13C(d, p)14C reaction in the study of compound nucleus formation as well as in some astrophysics scenarios, and the importance of the development of the AMS technique to measure cross sections of nuclear reactions of astrophysical interest in Mixico are also discussed.

Frontier applications of electrostatic accelerators

NASA Astrophysics Data System (ADS)

Liu, Ke-Xin; Wang, Yu-Gang; Fan, Tie-Shuan; Zhang, Guo-Hui; Chen, Jia-Er

2013-10-01

Electrostatic accelerator is a powerful tool in many research fields, such as nuclear physics, radiation biology, material science, archaeology and earth sciences. Two electrostatic accelerators, one is the single stage Van de Graaff with terminal voltage of 4.5 MV and another one is the EN tandem with terminal voltage of 6 MV, were installed in 1980s and had been put into operation since the early 1990s at the Institute of Heavy Ion Physics. Many applications have been carried out since then. These two accelerators are described and summaries of the most important applications on neutron physics and technology, radiation biology and material science, as well as accelerator mass spectrometry (AMS) are presented.

An assessment of coupling algorithms for nuclear reactor core physics simulations

DOE PAGES

Hamilton, Steven; Berrill, Mark; Clarno, Kevin; ...

2016-04-01

This paper evaluates the performance of multiphysics coupling algorithms applied to a light water nuclear reactor core simulation. The simulation couples the k-eigenvalue form of the neutron transport equation with heat conduction and subchannel flow equations. We compare Picard iteration (block Gauss–Seidel) to Anderson acceleration and multiple variants of preconditioned Jacobian-free Newton–Krylov (JFNK). The performance of the methods are evaluated over a range of energy group structures and core power levels. A novel physics-based approximation to a Jacobian-vector product has been developed to mitigate the impact of expensive on-line cross section processing steps. Furthermore, numerical simulations demonstrating the efficiency ofmore » JFNK and Anderson acceleration relative to standard Picard iteration are performed on a 3D model of a nuclear fuel assembly. Both criticality (k-eigenvalue) and critical boron search problems are considered.« less

An assessment of coupling algorithms for nuclear reactor core physics simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamilton, Steven; Berrill, Mark; Clarno, Kevin

This paper evaluates the performance of multiphysics coupling algorithms applied to a light water nuclear reactor core simulation. The simulation couples the k-eigenvalue form of the neutron transport equation with heat conduction and subchannel flow equations. We compare Picard iteration (block Gauss–Seidel) to Anderson acceleration and multiple variants of preconditioned Jacobian-free Newton–Krylov (JFNK). The performance of the methods are evaluated over a range of energy group structures and core power levels. A novel physics-based approximation to a Jacobian-vector product has been developed to mitigate the impact of expensive on-line cross section processing steps. Furthermore, numerical simulations demonstrating the efficiency ofmore » JFNK and Anderson acceleration relative to standard Picard iteration are performed on a 3D model of a nuclear fuel assembly. Both criticality (k-eigenvalue) and critical boron search problems are considered.« less

An assessment of coupling algorithms for nuclear reactor core physics simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamilton, Steven, E-mail: hamiltonsp@ornl.gov; Berrill, Mark, E-mail: berrillma@ornl.gov; Clarno, Kevin, E-mail: clarnokt@ornl.gov

This paper evaluates the performance of multiphysics coupling algorithms applied to a light water nuclear reactor core simulation. The simulation couples the k-eigenvalue form of the neutron transport equation with heat conduction and subchannel flow equations. We compare Picard iteration (block Gauss–Seidel) to Anderson acceleration and multiple variants of preconditioned Jacobian-free Newton–Krylov (JFNK). The performance of the methods are evaluated over a range of energy group structures and core power levels. A novel physics-based approximation to a Jacobian-vector product has been developed to mitigate the impact of expensive on-line cross section processing steps. Numerical simulations demonstrating the efficiency of JFNKmore » and Anderson acceleration relative to standard Picard iteration are performed on a 3D model of a nuclear fuel assembly. Both criticality (k-eigenvalue) and critical boron search problems are considered.« less

Position-sensitive coincidence detection of nuclear reaction products at the Prague Van-de-Graaff accelerator

NASA Astrophysics Data System (ADS)

Granja, Carlos; Kraus, Vaclav; Pugatch, Valery; Kohout, Zdenek

2017-06-01

In low-energy nuclear reactions of astrophysical interest or fusion studies the spatial- and time-correlated detection of two and more reaction products can be a valuable tool in studies of reaction mechanisms, resolving reaction channels and measuring angular distributions of reaction products. For this purpose we constructed a configurable array of position-sensitive detectors based on the hybrid semiconductor pixel detector Timepix. Additional analog-signal electronics provide self-trigger together with extended multi-device control and synchronized readout electronics by a customized control and coincidence unit. The instrumentation, developed and used for detection of fission fragments in spontaneous and neutron induced fission as well as in charged particle detection in neutron induced reactions, is being implemented for low-energy light-ion induced nuclear reactions. Application and demonstration of the technique with two Timepix detectors on p+p elastic scattering at the Van-de-Graaff (VdG) accelerator in Prague is given.

Characterization of Hydrogen Embrittled Zircaloy-4 by Using a Van de Graaff Particle Accelerator

NASA Astrophysics Data System (ADS)

Budd, John

2013-04-01

On-site, dry cask storage was originally by the intended to be a short-term solution for holding spent nuclear fuel. Due to the lack of a permanent storage facility, the nuclear power industry seeks to assess the effective lifetime of the casks. One issue which could compromise cask integrity is Hydrogen embrittlement. This phenomenon occurs in the Zircaloy-4 fuel-rod cladding and is caused by the formation of Zirconium hydrides. Over time, thermal stresses caused by the heat from reactions of the stored nuclear fuel could result in significant breaches of the cladding. Our group at Texas A&M University- Kingsville is conducting experiments to aid in determining when such breaches will occur. We will irradiate samples of the alloy with protons of energies up to 400 keV using a Van de Graaff particle accelerator. Once irradiated, their properties will be characterized using scanning electron microscopy and Vickers hardness tests.

Observation of the antimatter helium-4 nucleus.

PubMed

2011-05-19

High-energy nuclear collisions create an energy density similar to that of the Universe microseconds after the Big Bang; in both cases, matter and antimatter are formed with comparable abundance. However, the relatively short-lived expansion in nuclear collisions allows antimatter to decouple quickly from matter, and avoid annihilation. Thus, a high-energy accelerator of heavy nuclei provides an efficient means of producing and studying antimatter. The antimatter helium-4 nucleus (4He), also known as the anti-α (α), consists of two antiprotons and two antineutrons (baryon number B = -4). It has not been observed previously, although the α-particle was identified a century ago by Rutherford and is present in cosmic radiation at the ten per cent level. Antimatter nuclei with B < -1 have been observed only as rare products of interactions at particle accelerators, where the rate of antinucleus production in high-energy collisions decreases by a factor of about 1,000 with each additional antinucleon. Here we report the observation of 4He, the heaviest observed antinucleus to date. In total, 18 4He counts were detected at the STAR experiment at the Relativistic Heavy Ion Collider (RHIC; ref. 6) in 10(9) recorded gold-on-gold (Au+Au) collisions at centre-of-mass energies of 200 GeV and 62 GeV per nucleon-nucleon pair. The yield is consistent with expectations from thermodynamic and coalescent nucleosynthesis models, providing an indication of the production rate of even heavier antimatter nuclei and a benchmark for possible future observations of 4He in cosmic radiation.

Observation of the antimatter helium-4 nucleus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agakishiev, H.; Tang, A.; et al.

2011-04-24

High-energy nuclear collisions create an energy density similar to that of the Universe microseconds after the Big Bang; in both cases, matter and antimatter are formed with comparable abundance. However, the relatively short-lived expansion in nuclear collisions allows antimatter to decouple quickly from matter, and avoid annihilation. Thus, a high-energy accelerator of heavy nuclei provides an efficient means of producing and studying antimatter. The antimatter helium-4 nucleus ({sup 4}He), also known as the anti-{alpha} ({alpha}), consists of two antiprotons and two antineutrons (baryon number B = -4). It has not been observed previously, although the {alpha}-particle was identified a centurymore » ago by Rutherford and is present in cosmic radiation at the ten per cent level. Antimatter nuclei with B < -1 have been observed only as rare products of interactions at particle accelerators, where the rate of antinucleus production in high-energy collisions decreases by a factor of about 1,000 with each additional antinucleon. Here we report the observation of {sup 4}He, the heaviest observed antinucleus to date. In total, 18 {sup 4}He counts were detected at the STAR experiment at the Relativistic Heavy Ion Collider (RHIC) in 10{sup 9} recorded gold-on-gold (Au+Au) collisions at centre-of-mass energies of 200 GeV and 62 GeV per nucleon-nucleon pair. The yield is consistent with expectations from thermodynamic and coalescent nucleosynthesis models, providing an indication of the production rate of even heavier antimatter nuclei and a benchmark for possible future observations of {sup 4}He in cosmic radiation.« less

Production of Synthetic Nuclear Melt Glass

PubMed Central

Molgaard, Joshua J.; Auxier, John D.; Giminaro, Andrew V.; Oldham, Colton J.; Gill, Jonathan; Hall, Howard L.

2016-01-01

Realistic surrogate nuclear debris is needed within the nuclear forensics community to test and validate post-detonation analysis techniques. Here we outline a novel process for producing bulk surface debris using a high temperature furnace. The material developed in this study is physically and chemically similar to trinitite (the melt glass produced by the first nuclear test). This synthetic nuclear melt glass is assumed to be similar to the vitrified material produced near the epicenter (ground zero) of any surface nuclear detonation in a desert environment. The process outlined here can be applied to produce other types of nuclear melt glass including that likely to be formed in an urban environment. This can be accomplished by simply modifying the precursor matrix to which this production process is applied. The melt glass produced in this study has been analyzed and compared to trinitite, revealing a comparable crystalline morphology, physical structure, void fraction, and chemical composition. PMID:26779720

High Energy Ion Acceleration by Extreme Laser Radiation Pressure

DTIC Science & Technology

2017-03-14

and was published in Nuclear Instruments and Methods A [11]. For similar targets, it was found that by monitoring the divergence of a low- energy ...AFRL-AFOSR-UK-TR-2017-0015 High energy ion acceleration by extreme laser radiation pressure Paul McKenna UNIVERSITY OF STRATHCLYDE VIZ ROYAL COLLEGE...MM-YYYY)   14-03-2017 2. REPORT TYPE  Final 3. DATES COVERED (From - To)  01 May 2013 to 31 Dec 2016 4. TITLE AND SUBTITLE High energy ion acceleration

Induction Heating Model of Cermet Fuel Element Environmental Test (CFEET)

NASA Technical Reports Server (NTRS)

Gomez, Carlos F.; Bradley, D. E.; Cavender, D. P.; Mireles, O. R.; Hickman, R. R.; Trent, D.; Stewart, E.

2013-01-01

Deep space missions with large payloads require high specific impulse and relatively high thrust to achieve mission goals in reasonable time frames. Nuclear Thermal Rockets (NTR) are capable of producing a high specific impulse by employing heat produced by a fission reactor to heat and therefore accelerate hydrogen through a rocket nozzle providing thrust. Fuel element temperatures are very high (up to 3000 K) and hydrogen is highly reactive with most materials at high temperatures. Data covering the effects of high-temperature hydrogen exposure on fuel elements are limited. The primary concern is the mechanical failure of fuel elements due to large thermal gradients; therefore, high-melting-point ceramics-metallic matrix composites (cermets) are one of the fuels under consideration as part of the Nuclear Cryogenic Propulsion Stage (NCPS) Advance Exploration System (AES) technology project at the Marshall Space Flight Center. The purpose of testing and analytical modeling is to determine their ability to survive and maintain thermal performance in a prototypical NTR reactor environment of exposure to hydrogen at very high temperatures and obtain data to assess the properties of the non-nuclear support materials. The fission process and the resulting heating performance are well known and do not require that active fissile material to be integrated in this testing. A small-scale test bed; Compact Fuel Element Environmental Tester (CFEET), designed to heat fuel element samples via induction heating and expose samples to hydrogen is being developed at MSFC to assist in optimal material and manufacturing process selection without utilizing fissile material. This paper details the analytical approach to help design and optimize the test bed using COMSOL Multiphysics for predicting thermal gradients induced by electromagnetic heating (Induction heating) and Thermal Desktop for radiation calculations.

Massive global ozone loss predicted following regional nuclear conflict

PubMed Central

Mills, Michael J.; Toon, Owen B.; Turco, Richard P.; Kinnison, Douglas E.; Garcia, Rolando R.

2008-01-01

We use a chemistry-climate model and new estimates of smoke produced by fires in contemporary cities to calculate the impact on stratospheric ozone of a regional nuclear war between developing nuclear states involving 100 Hiroshima-size bombs exploded in cities in the northern subtropics. We find column ozone losses in excess of 20% globally, 25–45% at midlatitudes, and 50–70% at northern high latitudes persisting for 5 years, with substantial losses continuing for 5 additional years. Column ozone amounts remain near or <220 Dobson units at all latitudes even after three years, constituting an extratropical “ozone hole.” The resulting increases in UV radiation could impact the biota significantly, including serious consequences for human health. The primary cause for the dramatic and persistent ozone depletion is heating of the stratosphere by smoke, which strongly absorbs solar radiation. The smoke-laden air rises to the upper stratosphere, where removal mechanisms are slow, so that much of the stratosphere is ultimately heated by the localized smoke injections. Higher stratospheric temperatures accelerate catalytic reaction cycles, particularly those of odd-nitrogen, which destroy ozone. In addition, the strong convection created by rising smoke plumes alters the stratospheric circulation, redistributing ozone and the sources of ozone-depleting gases, including N2O and chlorofluorocarbons. The ozone losses predicted here are significantly greater than previous “nuclear winter/UV spring” calculations, which did not adequately represent stratospheric plume rise. Our results point to previously unrecognized mechanisms for stratospheric ozone depletion. PMID:18391218

Rate heterogeneity in six protein-coding genes from the holoparasite Balanophora (Balanophoraceae) and other taxa of Santalales

PubMed Central

Su, Huei-Jiun; Hu, Jer-Ming

2012-01-01

Background and Aims The holoparasitic flowering plant Balanophora displays extreme floral reduction and was previously found to have enormous rate acceleration in the nuclear 18S rDNA region. So far, it remains unclear whether non-ribosomal, protein-coding genes of Balanophora also evolve in an accelerated fashion and whether the genes with high substitution rates retain their functionality. To tackle these issues, six different genes were sequenced from two Balanophora species and their rate variation and expression patterns were examined. Methods Sequences including nuclear PI, euAP3, TM6, LFY and RPB2 and mitochondrial matR were determined from two Balanophora spp. and compared with selected hemiparasitic species of Santalales and autotrophic core eudicots. Gene expression was detected for the six protein-coding genes and the expression patterns of the three B-class genes (PI, AP3 and TM6) were further examined across different organs of B. laxiflora using RT-PCR. Key Results Balanophora mitochondrial matR is highly accelerated in both nonsynonymous (dN) and synonymous (dS) substitution rates, whereas the rate variation of nuclear genes LFY, PI, euAP3, TM6 and RPB2 are less dramatic. Significant dS increases were detected in Balanophora PI, TM6, RPB2 and dN accelerations in euAP3. All of the protein-coding genes are expressed in inflorescences, indicative of their functionality. PI is restrictively expressed in tepals, synandria and floral bracts, whereas AP3 and TM6 are widely expressed in both male and female inflorescences. Conclusions Despite the observation that rates of sequence evolution are generally higher in Balanophora than in hemiparasitic species of Santalales and autotrophic core eudicots, the five nuclear protein-coding genes are functional and are evolving at a much slower rate than 18S rDNA. The mechanism or mechanisms responsible for rapid sequence evolution and concomitant rate acceleration for 18S rDNA and matR are currently not well understood and require further study in Balanophora and other holoparasites. PMID:23041381

Flow-accelerated corrosion 2016 international conference

NASA Astrophysics Data System (ADS)

Tomarov, G. V.; Shipkov, A. A.

2017-05-01

The paper discusses materials and results of the most representative world forum on the problems of flow-accelerated metal corrosion in power engineering—Flow-Accelerated Corrosion (FAC) 2016, the international conference, which was held in Lille (France) from May 23 through May 27, 2016, sponsored by EdF-DTG with the support of the International Atomic Energy Agency (IAEA) and the World Association of Nuclear Operators (WANO). The information on major themes of reports and materials of the exhibition arranged within the framework of the congress is presented. The statistics on operation time and intensity of FAC wall thinning of NPP pipelines and equipment in the world is set out. The paper describes typical examples of flow-accelerated corrosion damage of condensate-feed and wet-steam pipeline components of nuclear and thermal power plants that caused forced shutdowns or accidents. The importance of research projects on the problem of flow-accelerated metal corrosion of nuclear power units coordinated by the IAEA with the participation of leading experts in this field from around the world is considered. The reports presented at the conference considered issues of implementation of an FAC mechanism in single- and two-phase flows, the impact of hydrodynamic and water-chemical factors, the chemical composition of the metal, and other parameters on the intensity and location of FAC wall thinning localized areas in pipeline components and power equipment. Features and patterns of local and general FAC leading to local metal thinning and contamination of the working environment with ferriferous compounds are considered. Main trends of modern practices preventing FAC wear of NPP pipelines and equipment are defined. An increasing role of computer codes for the assessment and prediction of FAC rate, as well as software systems of support of the NPP personnel for the inspection planning and prevention of FAC wall thinning of equipment operating in singleand two-phase flows, is accepted. Different lines of attack on the problem of FAC of pipelines and equipment components of existing and future nuclear power units are reviewed. Promising methods of nondestructive inspection of pipelines and equipment are presented.

DARHT Axis-I Diode Simulations II: Geometrical Scaling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ekdahl, Carl A. Jr.

2012-06-14

Flash radiography of large hydrodynamic experiments driven by high explosives is a venerable diagnostic technique in use at many laboratories. Many of the largest hydrodynamic experiments study mockups of nuclear weapons, and are often called hydrotests for short. The dual-axis radiography for hydrodynamic testing (DARHT) facility uses two electron linear-induction accelerators (LIA) to produce the radiographic source spots for perpendicular views of a hydrotest. The first of these LIAs produces a single pulse, with a fixed {approx}60-ns pulsewidth. The second axis LIA produces as many as four pulses within 1.6-{micro}s, with variable pulsewidths and separation. There are a wide varietymore » of hydrotest geometries, each with a unique radiographic requirement, so there is a need to adjust the radiographic dose for the best images. This can be accomplished on the second axis by simply adjusting the pulsewidths, but is more problematic on the first axis. Changing the beam energy or introducing radiation attenuation also changes the spectrum, which is undesirable. Moreover, using radiation attenuation introduces significant blur, increasing the effective spot size. The dose can also be adjusted by changing the beam kinetic energy. This is a very sensitive method, because the dose scales as the {approx}2.8 power of the energy, but it would require retuning the accelerator. This leaves manipulating the beam current as the best means for adjusting the dose, and one way to do this is to change the size of the cathode. This method has been proposed, and is being tested. This article describes simulations undertaken to develop scaling laws for use as design tools in changing the Axis-1 beam current by changing the cathode size.« less

Wake shed by an accelerating carangiform fish

NASA Astrophysics Data System (ADS)

Ting, Shang-Chieh; Yang, Jing-Tang

2008-11-01

We reveal an important fact that momentum change observed in the wake of an accelerating carangiform fish does not necessarily elucidate orientations of propulsive forces produced. An accelerating Crucian Carp (Carassius auratus) was found to shed a wake with net forward fluid momentum, which seemed drag-producing. Based on Newton's law, however, an accelerating fish is expected to shed a thrust wake with net rearward fluid momentum, rather than a drag wake. The unusual wake pattern observed is considered to be resulted primarily from the effect of pressure gradient created by accelerating movements of the fish. Ambient fluids tend to be sucked into low pressure zones behind an accelerating fish, resulting in forward orientations of jets recognizable in the wake. Accordingly, as to an accelerating fish, identifying force orientations from the wake requires considering also the effect of pressure gradient.

Laser driven ion accelerator

DOEpatents

Tajima, Toshiki

2006-04-18

A system and method of accelerating ions in an accelerator to optimize the energy produced by a light source. Several parameters may be controlled in constructing a target used in the accelerator system to adjust performance of the accelerator system. These parameters include the material, thickness, geometry and surface of the target.

Options for Accelerating Economic Recovery after Nuclear Attack. Volume 3

DTIC Science & Technology

1979-07-01

speed of data processing. It really ought to be possible to program computers with likely locations of needs, and then locations of ablebodied people...that a number of existing programs and institutions were imple- mented when public concerns over the risk of nuclear war were considerably higher...natural disasters are funded as programs if such programs would also be appropriate to the post-nuclear attack situation. This logic has a compelling

Design and commissioning of a 16.1 MHz multiharmonic buncher for the reaccelerator at NSCL

NASA Astrophysics Data System (ADS)

Alt, Daniel Maloney

The ReAccelerator (ReA) linear accelerator facility at the National Superconducting Cyclotron Laboratory is a unique resource for the nuclear physics community. The particle fragmentation beam production technique, combined with the ability to stop and then reaccelerate the beam to energies of astrophysical interest, give experimenters an unprecedented range of rare isotopes at energies of nuclear and astrophysical interest. The ReAccelerator also functions as a testbed for technology to be incorporated in the upcoming Facility for Rare Isotope Beams linear accelerator, which will eventually in turn become the beam source for ReA. This prototype nature of the ReAccelerator, however, dictated some design choices which have resulted in a final beam with a time structure that is less than ideal for certain classes of experiments. The cavities and RFQ used in ReA have an operating frequency of 80.5 MHz, which corresponds to a separation between particle bunches at the detectors of 12.4 ns. While this separation is acceptable for many experiments, sensitive time of flight measurements require a greater separation between pulses. As nuclear physics experiments rely on statistics, a solution to increasing bunch separation without simply discarding a large fraction of the beam particles was desired. This document describes the design and construction of such a device, a 16.1 MHz multiharmonic buncher. The first chapter provides backgound information on the NSCL and ReA, and some basic concepts in accelerator physics to lay the groundwork for the project.Next, more specifics are provided on the time structure of accelerated beams, and the experimental motivation for greater separation. The third chapter outlines the basic principles of multiharmonic bunching. In order to evaluate the feasibility of any buncher design, the exact acceptance of the Radiofrequency Quadrupole (RFQ) of the ReAccelerator needed to be empirically measured. Chapter 4 describes the results of that measurement. Chapter 5 outlines the simulations and calculations that went into the design choices for this particular buncher, incorporating the results of the RFQ measurements. The next two chapters describe the construction, installation, and testing of the device, and give experimental results. Finally, Chapter 8 summarizes the project and the final steps which need to be undertaken to make the device a simple to use asset for future experimentalists at ReA.

Method of producing molybdenum-99

DOEpatents

Pitcher, Eric John

2013-05-28

Method of producing molybdenum-99, comprising accelerating ions by means of an accelerator; directing the ions onto a metal target so as to generate neutrons having an energy of greater than 10 MeV; directing the neutrons through a converter material comprising techentium-99 to produce a mixture comprising molybdenum-99; and, chemically extracting the molybdenum-99 from the mixture.

Integrated nuclear data utilisation system for innovative reactors.

PubMed

Yamano, N; Hasegawa, A; Kato, K; Igashira, M

2005-01-01

A five-year research and development project on an integrated nuclear data utilisation system was initiated in 2002, for developing innovative nuclear energy systems such as accelerator-driven systems. The integrated nuclear data utilisation system will be constructed as a modular code system, which consists of two sub-systems: the nuclear data search and plotting sub-system, and the nuclear data processing and utilisation sub-system. The system will be operated with a graphical user interface in order to enable easy utilisation through the Internet by both nuclear design engineers and nuclear data evaluators. This paper presents an overview of the integrated nuclear data utilisation system, describes the development of a prototype system to examine the operability of the user interface and discusses specifications of the two sub-systems.

Nuclear Science and Applications with the Next Generation of High-Power Lasers and Brilliant Low-Energy Gamma Beams at ELI-NP

NASA Astrophysics Data System (ADS)

Gales, S.

The development of high power lasers and the combination of such novel devices with accelerator technology has enlarged the science reach of many research fields, in particular Particle and Nuclear Physics, Astrophysics as well as societal applications in Material Science, Nuclear Energy and Medicine. The European Strategic Forum for Research Infrastructures (ESFRI) has selected a proposal based on these new premises called "ELI" for Extreme Light Infrastructure. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for Nuclear Physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW lasers and a Compton back-scattering high-brilliance and intense low-energy gamma beam, a marriage of laser and accelerator technology at the frontier of knowledge. In the present paper, the technical description of the facility, the present status of the project as well as the science, applications and future perspectives will be discussed.

Nuclear Science and Applications with the Next Generation of High-Power Lasers and Brilliant Low-Energy Gamma Beams at ELI-NP

NASA Astrophysics Data System (ADS)

Gales, S.

2015-11-01

The development of high-power lasers and the combination of such novel devices with accelerator technology has enlarged the science reach of many research fields, in particular high-energy nuclear physics and astrophysics, as well as societal applications in material science, nuclear energy and medicine. The European Strategic Forum for Research Infrastructures (ESFRI) has selected a proposal based on these new premises called "ELI" for Extreme Light Infrastructure. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for nuclear physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10-PW lasers and a Compton back-scattering high-brilliance and intense low-energy gamma beam, a marriage of laser and accelerator technology at the frontier of knowledge. In the present paper, the technical description of the facility, the present status of the project as well as the science, applications and future perspectives will be discussed.

Research at the University of Kentucky Accelerator Laboratory

DOE PAGES

Hicks, S. F.; Kovash, M. A.

2017-10-26

The Department of Physics and Astronomy at the University of Kentucky operates a 7-MV CN Van de Graaff accelerator that produces primary beams of protons, deuterons, and helium ions. An in-terminal pulsing and bunching system operates at 1.875 MHz and is capable of providing 1 ns beam bunches at an average current of several microamperes. Nearly all ongoing research programs involve secondary pulsed neutrons produced with gas cells containing deuterium or tritium, as well as with a variety of solid targets. Most experiments are performed at a target station positioned over a deep pit, so as to reduce the backgroundmore » created by backscattered neutrons. Here, recent experiments will be described; these include: measurements of n-p scattering total cross sections from E n = 90 to 1800 keV to determine the n-p effective range parameter; the response of the plastic scintillator BC-418 below 1 MeV to low-energy recoil protons; n-p radiative capture cross sections important for our understanding of nucleosynthesis approximately 2 minutes after the occurrence of the Big Bang; γ-ray spectroscopy following inelastic neutron scattering to study nuclear structure relevant to double-β decay and to understand the role of phonon-coupled excitations in weakly deformed nuclei; and measurements of neutron elastic and inelastic scattering cross sections for nuclei that are important for energy production and for our global understanding of the interaction of neutrons with matter.« less

Research at the University of Kentucky Accelerator Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hicks, S. F.; Kovash, M. A.

The Department of Physics and Astronomy at the University of Kentucky operates a 7-MV CN Van de Graaff accelerator that produces primary beams of protons, deuterons, and helium ions. An in-terminal pulsing and bunching system operates at 1.875 MHz and is capable of providing 1 ns beam bunches at an average current of several microamperes. Nearly all ongoing research programs involve secondary pulsed neutrons produced with gas cells containing deuterium or tritium, as well as with a variety of solid targets. Most experiments are performed at a target station positioned over a deep pit, so as to reduce the backgroundmore » created by backscattered neutrons. Here, recent experiments will be described; these include: measurements of n-p scattering total cross sections from E n = 90 to 1800 keV to determine the n-p effective range parameter; the response of the plastic scintillator BC-418 below 1 MeV to low-energy recoil protons; n-p radiative capture cross sections important for our understanding of nucleosynthesis approximately 2 minutes after the occurrence of the Big Bang; γ-ray spectroscopy following inelastic neutron scattering to study nuclear structure relevant to double-β decay and to understand the role of phonon-coupled excitations in weakly deformed nuclei; and measurements of neutron elastic and inelastic scattering cross sections for nuclei that are important for energy production and for our global understanding of the interaction of neutrons with matter.« less

Neutron Energy Spectra and Yields from the 7Li(p,n) Reaction for Nuclear Astrophysics

NASA Astrophysics Data System (ADS)

Tessler, M.; Friedman, M.; Schmidt, S.; Shor, A.; Berkovits, D.; Cohen, D.; Feinberg, G.; Fiebiger, S.; Krása, A.; Paul, M.; Plag, R.; Plompen, A.; Reifarth, R.

2016-01-01

Neutrons produced by the 7Li(p, n)7Be reaction close to threshold are widely used to measure the cross section of s-process nucleosynthesis reactions. While experiments have been performed so far with Van de Graaff accelerators, the use of RF accelerators with higher intensities is planned to enable investigations on radioactive isotopes. In parallel, high-power Li targets for the production of high-intensity neutrons at stellar energies are developed at Goethe University (Frankfurt, Germany) and SARAF (Soreq NRC, Israel). However, such setups pose severe challenges for the measurement of the proton beam intensity or the neutron fluence. In order to develop appropriate methods, we studied in detail the neutron energy distribution and intensity produced by the thick-target 7Li(p,n)7Be reaction and compared them to state-of- the-art simulation codes. Measurements were performed with the bunched and chopped proton beam at the Van de Graaff facility of the Institute for Reference Materials and Measurements (IRMM) using the time-of-flight (TOF) technique with thin (1/8") and thick (1") detectors. The importance of detailed simulations of the detector structure and geometry for the conversion of TOF to a neutron energy is stressed. The measured neutron spectra are consistent with those previously reported and agree well with Monte Carlo simulations that include experimentally determined 7Li(p,n) cross sections, two-body kinematics and proton energy loss in the Li-target.

The Role of Linear Acceleration in Visual-Vestibular Interactions and Implications in Aircraft Operations

NASA Technical Reports Server (NTRS)

Correia, Manning J.; Luke, Brian L.; McGrath, Braden J.; Clark, John B.; Rupert, Angus H.

1996-01-01

While considerable attention has been given to visual-vestibular interaction (VVI) during angular motion of the head as might occur during an aircraft spin, much less attention has been given to VVI during linear motion of the head. Such interaction might occur, for example, while viewing a stationary or moving display during vertical take-off and landing operations Research into linear VVI, particularly during prolonged periods of linear acceleration, has been hampered by the unavailability of a programmable translator capable of large excursions We collaborated with Otis Elevator Co. and used their research tower and elevator, whose motion could be digitally programmed, to vertically translate human subjects over a distance of 92.3 meters with a peak linear acceleration of 2 meters/sec(exp 2) During pulsatile or sinusoidal translation, the subjects viewed moving stripes (optokinetic stimulus) or a fixed point source (light emitting diode, led, display), respectively and it was generally found that. The direction of linear acceleration relative to the cardinal head axes and the direction of the slow component of optokinetic nystagmus (OKN) determined the extent of VVI during concomitant stripe motion and linear acceleration. Acceleration along the z head axis (A(sub z)) produced the largest VVI, particularly when the slow component of OKN was in the same direction as eye movements produced by the linear acceleration and Eye movements produced by linear acceleration are suppressed by viewing a fixed target at frequencies below 10 Hz But, above this frequency the suppression produced by VVI is removed. Finally, as demonstrated in non-human primates, vergence of the eyes appears to modulate the vertical eye movement response to linear acceleration in humans.

Secure Transportation of HEU in Romania

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2009-07-06

The National Nuclear Security Administration has announced the final shipments of Russian-origin highly enriched uranium (HEU) nuclear fuel from Romania. The material was removed and returned to Russia by air for storage at two secure nuclear facilities, making Romania the first country to remove all HEU since President Obama outlined his commitment to securing all vulnerable nuclear material around the world within four years. This was also the first time NNSA has shipped spent HEU by airplane, a development that will help accelerate efforts to meet the Presidents objective.

Neutron imaging with the short-pulse laser driven neutron source at the TRIDENT Laser Facility

DOE PAGES

Guler, Nevzat; Volegov, Petr Lvovich; Favalli, Andrea; ...

2016-10-17

Emerging approaches to short-pulse laser-driven neutron production offer a possible gateway to compact, low cost, and intense broad spectrum sources for a wide variety of applications. They are based on energetic ions, driven by an intense short-pulse laser, interacting with a converter material to produce neutrons via breakup and nuclear reactions. Recent experiments performed with the high-contrast laser at the Trident laser facility of Los Alamos National Laboratory have demonstrated a laser-driven ion acceleration mechanism operating in the regime of relativistic transparency, featuring a volumetric laser-plasma interaction. This mechanism is distinct from previously studied ones that accelerate ions at themore » laser-target surface. The Trident experiments produced an intense beam of deuterons with an energy distribution extending above 100 MeV. This deuteron beam, when directed at a beryllium converter, produces a forward-directed neutron beam with ~5x10 9 n/sr, in a single laser shot, primarily due to deuteron breakup. The neutron beam has a pulse duration on the order of a few nanoseconds with an energy distribution extending from a few hundreds of keV to almost 80 MeV. For the experiments on neutron-source spot-size measurements, our gated neutron imager was setup to select neutrons in the energy range of 2.5 to 35 MeV. The spot size of neutron emission at the converter was measured by two different imaging techniques, using a knife-edge and a penumbral aperture, in two different experimental campaigns. The neutron-source spot size is measured ~1 mm for both experiments. The measurements and analysis reported here give a spatial characterization for this type of neutron source for the first time. In addition, the forward modeling performed provides an empirical estimate of the spatial characteristics of the deuteron ion-beam. Finally, these experimental observations, taken together, provide essential yet unique data to benchmark and verify theoretical work into the basic acceleration mechanism, which remains an ongoing challenge.« less

Neutron imaging with the short-pulse laser driven neutron source at the TRIDENT Laser Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guler, Nevzat; Volegov, Petr Lvovich; Favalli, Andrea

Emerging approaches to short-pulse laser-driven neutron production offer a possible gateway to compact, low cost, and intense broad spectrum sources for a wide variety of applications. They are based on energetic ions, driven by an intense short-pulse laser, interacting with a converter material to produce neutrons via breakup and nuclear reactions. Recent experiments performed with the high-contrast laser at the Trident laser facility of Los Alamos National Laboratory have demonstrated a laser-driven ion acceleration mechanism operating in the regime of relativistic transparency, featuring a volumetric laser-plasma interaction. This mechanism is distinct from previously studied ones that accelerate ions at themore » laser-target surface. The Trident experiments produced an intense beam of deuterons with an energy distribution extending above 100 MeV. This deuteron beam, when directed at a beryllium converter, produces a forward-directed neutron beam with ~5x10 9 n/sr, in a single laser shot, primarily due to deuteron breakup. The neutron beam has a pulse duration on the order of a few nanoseconds with an energy distribution extending from a few hundreds of keV to almost 80 MeV. For the experiments on neutron-source spot-size measurements, our gated neutron imager was setup to select neutrons in the energy range of 2.5 to 35 MeV. The spot size of neutron emission at the converter was measured by two different imaging techniques, using a knife-edge and a penumbral aperture, in two different experimental campaigns. The neutron-source spot size is measured ~1 mm for both experiments. The measurements and analysis reported here give a spatial characterization for this type of neutron source for the first time. In addition, the forward modeling performed provides an empirical estimate of the spatial characteristics of the deuteron ion-beam. Finally, these experimental observations, taken together, provide essential yet unique data to benchmark and verify theoretical work into the basic acceleration mechanism, which remains an ongoing challenge.« less

The TRIUMF nuclear structure program and TIGRESS

NASA Astrophysics Data System (ADS)

Garrett, P. E.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Becker, J. A.; Boston, A. J.; Boston, H. C.; Chakrawarthy, R. S.; Churchman, R.; Cline, D.; Cooper, R. J.; Cross, D.; Dashdorj, D.; Demand, G. A.; Dimmock, M. R.; Drake, T.; Finlay, P.; Gagnon, K.; Gallant, A. T.; Green, K. L.; Grint, A. N.; Grinyer, G. F.; Hackman, G.; Harkness, L. J.; Hayes, A. B.; Kanungo, R.; Kulp, W. D.; Leach, K. G.; Lee, G.; Leslie, J. R.; Maharaj, R.; Martin, J.-P.; Mattoon, C.; Mills, W. J.; Morton, A. C.; Nelson, L.; Newman, O.; Nolan, P. J.; Padilla-Rodal, E.; Pearson, C. J.; Phillips, A. A.; Porter-Peden, M.; Ressler, J. J.; Ruiz, C.; Sarazin, F.; Schumaker, M. A.; Scraggs, D. P.; Strange, M. D.; Subramanian, M.; Svensson, C. E.; Waddington, J. C.; Wan, J.; Whitbeck, A.; Williams, S. J.; Wood, J. L.; Wong, J. C.; Wu, C. Y.; Zganjar, E. F.

2007-08-01

The isotope separator and accelerator (ISAC) facility located at the TRIUMF laboratory in Vancouver, Canada, is one of the world's most advanced isotope separator on-line-type radioactive ion beam facilities. An extensive γ-ray spectroscopy programme at ISAC is centred around two major research facilities: (i) the 8π γ-ray spectrometer for β-delayed γ-ray spectroscopy experiments with the low-energy beams from ISAC-I, and (ii) the next generation TRIUMF-ISAC gamma-ray escape suppressed spectrometer (TIGRESS) for in-beam experiments with the accelerated radioactive-ion beams. An overview of these facilities and recent results from the diverse programme of nuclear structure and fundamental interaction studies they support is presented.

Sequentially pulsed traveling wave accelerator

DOEpatents

Caporaso, George J [Livermore, CA; Nelson, Scott D [Patterson, CA; Poole, Brian R [Tracy, CA

2009-08-18

A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.

What views and uses of radiation sources in the 21st century?

PubMed

Blix, H

2001-04-01

Considering that in 1899 neither biotechnology nor the electronic revolution were foreseen, some humility might be advisable when one looks into the crystal ball for the future role of radiation sources. In the past 50 years, nuclear medicine, nuclear weapons, and nuclear power have had a huge impact in the world. In the next 50 years, nuclear weapons may be phased out, nuclear power revived, and nuclear medicine may continue, especially for diagnostic purposes. Conflicts between great powers and blocks will no longer be about territorial or ideological domination but about trade, finance, information, and the environment and the weapons used will not be bombs but investments, credits, and control of information. Nuclear power-still based on fission-will be relaunched and get more uses, e.g., to propel ships, to produce heat for industry and for space heating, and perhaps to desalinate water. The public will be more at ease with radiation as it is better educated, as nuclear safety continuously improves and new types of nuclear power plants emerge, as waste sites fail to cause any problems, and as no other energy source is found to deliver so much energy at reasonable cost with negligible impact on climate and environment. One kilogram of oil corresponds to 4 kWh of electricity. One kilogram of uranium fuel corresponds to 50,000 kWh, and 1 kg of plutonium 6,000,000 kWh! In nuclear medicine, radiation may give way to other treatments as the understanding of cancer advances. On the other hand, the extreme ease with which sources of radiation can be identified is unmatched and likely to make them useful tools as tracers and markers in medicine-and other fields-for a long time. For certain uses--perhaps food irradiation--radiation sources, such as cobalt, may be replaced by accelerators which may be switched on and off at will. As more sources are used, registration and control of them must be made very effective around the whole world. Very high natural emissions of radon will continue to call for cautionary measures, but many other nonradiating substances will be identified as hazardous to health and call for vigorous intervention.

Facility for Antiproton and Ion Research, FAIR, at the GSI site

NASA Astrophysics Data System (ADS)

Rosner, Guenther

2006-11-01

FAIR is a new large-scale particle accelerator facility to be built at the GSI site in Germany. The research pursued at FAIR will cover a wide range of topics in nuclear and hadron physics, as well as high density plasma physics, atomic and antimatter physics, and applications in condensed matter physics and biology. The working horse of FAIR will be a 1.1km circumference double ring of rapidly cycling 100 and 300Tm synchrotrons, which will be used to produce high intensity secondary beams of short-lived radioactive ions or antiprotons. A subsequent suite of cooler and storage rings will deliver heavy ion and antiproton beams of unprecedented quality. Large experimental facilities are presently being designed by the NUSTAR, PANDA, PAX, CBM, SPARC, FLAIR, HEDgeHOB and BIOMAT collaborations.

Radiation curing progress in Hungary

NASA Astrophysics Data System (ADS)

Czvikovszky, T.

Radiation chemistry and radiation processing is an actively cultivated field of chemical technology and of applied research in several Central/Eastern European countries. Hungary, with his synthetic polymer production over 50 kg/capita/year, with his strong commitment in nuclear power production /almost 40 % of total electric power/, with his pioneering activity in food irradiation, radiation sterilization as well as EB processing of polymer — performs an iniciating role in this region. Actually four industrial EB machines are working in Hungary on plastics converting. Two of these accelerators, manufactured in SU are producing heat-shrinkable products. Two other, low-energy EB machines from FRG are working on industrial-scale surface-coating. An ELECTROCURTAIN /USA/ is serving R/D. Some actual problems of the applied radiation chemistry of EB-curing will be discussed.

10 CFR 74.33 - Nuclear material control and accounting for uranium enrichment facilities authorized to produce...

Code of Federal Regulations, 2011 CFR

2011-01-01

... enrichment facilities authorized to produce special nuclear material of low strategic significance. 74.33... NUCLEAR MATERIAL Special Nuclear Material of Low Strategic Significance § 74.33 Nuclear material control... strategic significance. (a) General performance objectives. Each licensee who is authorized by this chapter...

Changes in the direction of sight during parabolic flights and rectilinear accelerations

NASA Technical Reports Server (NTRS)

Von Baumgarten, R.; Thuemler, R.; Shillinger, G. L.; Baldrighi, G.

1973-01-01

Tests in which persons were subjected to a negative acceleration in an automobile are reported. The acceleration was obtained by stopping a moving car on the runway of an airport. The acceleration was found to produce a rotational movement of the subject's eyeball proportional to the degree of acceleration. Other investigations were conducted with a jet aircraft and a sports aircraft. G forces of up to 3 G were obtained during pull up of the aircraft, while values in the range from 0 to 1 G could be produced with the aid of a parabolic flight path. The effects of the flight conditions on the subject's direction of sight are discussed.

Compact particle accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elizondo-Decanini, Juan M.

2017-08-29

A compact particle accelerator having an input portion configured to receive power to produce particles for acceleration, where the input portion includes a switch, is provided. In a general embodiment, a vacuum tube receives particles produced from the input portion at a first end, and a plurality of wafer stacks are positioned serially along the vacuum tube. Each of the plurality of wafer stacks include a dielectric and metal-oxide pair, wherein each of the plurality of wafer stacks further accelerate the particles in the vacuum tube. A beam shaper coupled to a second end of the vacuum tube shapes themore » particles accelerated by the plurality of wafer stacks into a beam and an output portion outputs the beam.« less

Generation and characterization of electron bunches with ramped current profiles in a dual-frequency superconducting linear accelerator.

PubMed

Piot, P; Behrens, C; Gerth, C; Dohlus, M; Lemery, F; Mihalcea, D; Stoltz, P; Vogt, M

2012-01-20

We report on the successful experimental generation of electron bunches with ramped current profiles. The technique relies on impressing nonlinear correlations in the longitudinal phase space using a superconducing radio frequency linear accelerator operating at two frequencies and a current-enhancing dispersive section. The produced ~700-MeV bunches have peak currents of the order of a kilo-Ampère. Data taken for various accelerator settings demonstrate the versatility of the method and, in particular, its ability to produce current profiles that have a quasilinear dependency on the longitudinal (temporal) coordinate. The measured bunch parameters are shown, via numerical simulations, to produce gigavolt-per-meter peak accelerating electric fields with transformer ratios larger than 2 in dielectric-lined waveguides. © 2012 American Physical Society

Electron-ion collider: The next QCD frontier: Understanding the glue that binds us all

DOE Office of Scientific and Technical Information (OSTI.GOV)

Accardi, A.; Albacete, J. L.; Anselmino, M.

This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decadesmore » and, in particular, the focused ten-week program on “Gluons and quark sea at high energies” at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users’ communities of BNL and JLab. Furthermore, this White Paper offers the promise to propel the QCD science program in the US, established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.« less

Electron-ion collider: The next QCD frontier: Understanding the glue that binds us all

DOE PAGES

Accardi, A.; Albacete, J. L.; Anselmino, M.; ...

2016-09-08

This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decadesmore » and, in particular, the focused ten-week program on “Gluons and quark sea at high energies” at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users’ communities of BNL and JLab. Furthermore, this White Paper offers the promise to propel the QCD science program in the US, established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.« less

Ion Acceleration in Solar Flares

NASA Technical Reports Server (NTRS)

Miller, James A.; Weir, Sue B.

1996-01-01

Solar flares are among the most energetic and interesting phenomena in the Solar system, releasing up to 1032 ergs of energy on timescales of several tens of seconds to several tens of minutes. Much of this energy is in the form of suprathermal electrons and ions, which remain trapped at the Sun and produce a wide variety of radiations, as well as escape into interplanetary space, where they can be directly observed. The radiation from trapped particles consists in general of (1) continuum emission; (2) narrow gamma-ray nuclear deexcitation lines; and (3) high-energy neutrons observed in space or by ground-based neutron monitors. The particles that escape into space consist of both electrons and ions, which often have compositions quite different than that of the ambient solar atmosphere. Flares thus present many diagnostics of the particle acceleration mechanism(s), the identification of which is the ultimate goal of flare research. Moreover, flares in fact offer the only opportunity in astrophysics to study the simultaneous energization of both electrons and ions. Hopefully, an understanding of flares with their wealth of diagnostic data will lead to a better understanding of particle acceleration at other sites in the Universe. It is now generally accepted that flares are roughly divided into two classes: impulsive and gradual. Gradual events are large, occur high in the corona, have long-duration soft and hard X-rays and gamma rays, are electron poor, are associated with Type II radio emission and coronal mass ejections (CMEs), and produce energetic ions with coronal abundance ratios. Impulsive events are more compact, occur lower in the corona, produce short-duration radiation, and exhibit dramatic abundance enhancements in the energetic ions. Their He-3/He-4 ratio is - 1, which is a huge increase over the coronal value of about 5 x 10(exp -4), and they also posses smaller but still significant enhancements of Ne, Mg, Si, and Fe relative to He-4, C, N, and O. Specifically, above about 1 MeV nucleon(exp -1), the ratio of Fe to O is about 8 times larger than in the corona or in gradual flares, while the ratio of Ne, Mg, and Si to O is about 3 times higher; He-4, C, N, and 0 are not enchanced with respect to each other. In addition to these elemental enhancements, Ne and Mg have isotopic enhancements as well. The general scenario that has emerged from these (and other) observations is that energetic particles in gradual events are accelerated by a CME-driven shock, while those particles in impulsive events are accelerated by another mechanism(s).

CR-39 track detector calibration for H, He, and C ions from 0.1-0.5 MeV up to 5 MeV for laser-induced nuclear fusion product identification.

PubMed

Baccou, C; Yahia, V; Depierreux, S; Neuville, C; Goyon, C; Consoli, F; De Angelis, R; Ducret, J E; Boutoux, G; Rafelski, J; Labaune, C

2015-08-01

Laser-accelerated ion beams can be used in many applications and, especially, to initiate nuclear reactions out of thermal equilibrium. We have experimentally studied aneutronic fusion reactions induced by protons accelerated by the Target Normal Sheath Acceleration mechanism, colliding with a boron target. Such experiments require a rigorous method to identify the reaction products (alpha particles) collected in detectors among a few other ion species such as protons or carbon ions, for example. CR-39 track detectors are widely used because they are mostly sensitive to ions and their efficiency is near 100%. We present a complete calibration of CR-39 track detector for protons, alpha particles, and carbon ions. We give measurements of their track diameters for energy ranging from hundreds of keV to a few MeV and for etching times between 1 and 8 h. We used these results to identify alpha particles in our experiments on proton-boron fusion reactions initiated by laser-accelerated protons. We show that their number clearly increases when the boron fuel is preformed in a plasma state.

CR-39 track detector calibration for H, He, and C ions from 0.1-0.5 MeV up to 5 MeV for laser-induced nuclear fusion product identification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baccou, C., E-mail: claire.baccou@polytechnique.edu; Yahia, V.; Labaune, C.

Laser-accelerated ion beams can be used in many applications and, especially, to initiate nuclear reactions out of thermal equilibrium. We have experimentally studied aneutronic fusion reactions induced by protons accelerated by the Target Normal Sheath Acceleration mechanism, colliding with a boron target. Such experiments require a rigorous method to identify the reaction products (alpha particles) collected in detectors among a few other ion species such as protons or carbon ions, for example. CR-39 track detectors are widely used because they are mostly sensitive to ions and their efficiency is near 100%. We present a complete calibration of CR-39 track detectormore » for protons, alpha particles, and carbon ions. We give measurements of their track diameters for energy ranging from hundreds of keV to a few MeV and for etching times between 1 and 8 h. We used these results to identify alpha particles in our experiments on proton-boron fusion reactions initiated by laser-accelerated protons. We show that their number clearly increases when the boron fuel is preformed in a plasma state.« less

An Undulator-Based Laser Wakefield Accelerator Electron Beam Diagnostic

NASA Astrophysics Data System (ADS)

Bakeman, Michael S.

Currently particle accelerators such as the Large Hadron Collider use RF cavities with a maximum field gradient of 50-100 MV/m to accelerate particles over long distances. A new type of plasma based accelerator called a Laser Plasma Accelerator (LPA) is being investigated at the LOASIS group at Lawrence Berkeley National Laboratory which can sustain field gradients of 10-100 GV/m. This new type of accelerator offers the potential to create compact high energy accelerators and light sources. In order to investigate the feasibility of producing a compact light source an undulator-based electron beam diagnostic for use on the LOASIS LPA has been built and calibrated. This diagnostic relies on the principal that the spectral analysis of synchrotron radiation from an undulator can reveal properties of the electron beam such as emittance, energy and energy spread. The effects of electron beam energy spread upon the harmonics of undulator produced synchrotron radiation were derived from the equations of motion of the beam and numerically simulated. The diagnostic consists of quadrupole focusing magnets to collimate the electron beam, a 1.5 m long undulator to produce the synchrotron radiation, and a high resolution high gain XUV spectrometer to analyze the radiation. The undulator was aligned and tuned in order to maximize the flux of synchrotron radiation produced. The spectrometer was calibrated at the Advanced Light Source, with the results showing the ability to measure electron beam energy spreads at resolutions as low as 0.1% rms, a major improvement over conventional magnetic spectrometers. Numerical simulations show the ability to measure energy spreads on realistic LPA produced electron beams as well as the improvements in measurements made with the quadrupole magnets. Experimentally the quadrupoles were shown to stabilize and focus the electron beams at specific energies for their insertion into the undulator, with the eventual hope of producing an all optical Free Electron Laser operating in the XUV and soft x-ray regimes.

Monte carlo simulations of Yttrium reaction rates in Quinta uranium target

NASA Astrophysics Data System (ADS)

Suchopár, M.; Wagner, V.; Svoboda, O.; Vrzalová, J.; Chudoba, P.; Tichý, P.; Kugler, A.; Adam, J.; Závorka, L.; Baldin, A.; Furman, W.; Kadykov, M.; Khushvaktov, J.; Solnyshkin, A.; Tsoupko-Sitnikov, V.; Tyutyunnikov, S.; Bielewicz, M.; Kilim, S.; Strugalska-Gola, E.; Szuta, M.

2017-03-01

The international collaboration Energy and Transmutation of Radioactive Waste (E&T RAW) performed intensive studies of several simple accelerator-driven system (ADS) setups consisting of lead, uranium and graphite which were irradiated by relativistic proton and deuteron beams in the past years at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The most recent setup called Quinta, consisting of natural uranium target-blanket and lead shielding, was irradiated by deuteron beams in the energy range between 1 and 8 GeV in three accelerator runs at JINR Nuclotron in 2011 and 2012 with yttrium samples among others inserted inside the setup to measure the neutron flux in various places. Suitable activation detectors serve as one of possible tools for monitoring of proton and deuteron beams and for measurements of neutron field distribution in ADS studies. Yttrium is one of such suitable materials for monitoring of high energy neutrons. Various threshold reactions can be observed in yttrium samples. The yields of isotopes produced in the samples were determined using the activation method. Monte Carlo simulations of the reaction rates leading to production of different isotopes were performed in the MCNPX transport code and compared with the experimental results obtained from the yttrium samples.

Materials science education: ion beam modification and analysis of materials

NASA Astrophysics Data System (ADS)

Zimmerman, Robert; Muntele, Claudiu; Ila, Daryush

2012-08-01

The Center for Irradiation of Materials (CIM) at Alabama A&M University (http://cim.aamu.edu) was established in 1990 to serve the University in its research, education and services to the need of the local community and industry. CIM irradiation capabilities are oriented around two tandem-type ion accelerators with seven beam lines providing high-resolution Rutherford backscattering spectrometry, MeV focus ion beam, high-energy ion implantation and irradiation damage studies, particle-induced X-ray emission, particle-induced gamma emission and ion-induced nuclear reaction analysis in addition to fully automated ion channeling. One of the two tandem ion accelerators is designed to produce high-flux ion beam for MeV ion implantation and ion irradiation damage studies. The facility is well equipped with a variety of surface analysis systems, such as SEM, ESCA, as well as scanning micro-Raman analysis, UV-VIS Spectrometry, luminescence spectroscopy, thermal conductivity, electrical conductivity, IV/CV systems, mechanical test systems, AFM, FTIR, voltammetry analysis as well as low-energy implanters, ion beam-assisted deposition and MBE systems. In this presentation, we will demonstrate how the facility is used in material science education, as well as providing services to university, government and industry researches.

Spectral characterization of laser-accelerated protons with CR-39 nuclear track detector.

PubMed

Seimetz, M; Bellido, P; García, P; Mur, P; Iborra, A; Soriano, A; Hülber, T; García López, J; Jiménez-Ramos, M C; Lera, R; Ruiz-de la Cruz, A; Sánchez, I; Zaffino, R; Roso, L; Benlloch, J M

2018-02-01

CR-39 nuclear track material is frequently used for the detection of protons accelerated in laser-plasma interactions. The measurement of track densities allows for determination of particle angular distributions, and information on the kinetic energy can be obtained by the use of passive absorbers. We present a precise method of measuring spectral distributions of laser-accelerated protons in a single etching and analysis process. We make use of a one-to-one relation between proton energy and track size and present a precise calibration based on monoenergetic particle beams. While this relation is limited to proton energies below 1 MeV, we show that the range of spectral measurements can be significantly extended by simultaneous use of absorbers of suitable thicknesses. Examples from laser-plasma interactions are presented, and quantitative results on proton energies and particle numbers are compared to those obtained from a time-of-flight detector. The spectrum end points of continuous energy distributions have been determined with both detector types and coincide within 50-100 keV.

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

PubMed

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

2016-08-01

Interplanet and interstellar travels require long-term propulsion of spacecrafts, whereas the conventional schemes of propulsion are limited by the velocity of the ejected mass. In this study, alpha particles released by nuclear decay are considered as a potential solution for long-time acceleration. The principle of near-light-speed particle propulsion (NcPP) was elucidated and the stopping and range of ions in matter (SRIM) was used to predict theoretical accelerations. The results show that NcPP by means of alpha decay is feasible for long-term spacecraft propulsion and posture adjustment in space. A practical NcPP sail can achieve a speed >150km/s and reach the brink of the solar system faster than a mass equivalent solar sail. Finally, to significantly improve the NcPP sail, the hypothesis of stimulated acceleration of nuclear decay (SAND) was proposed, which may shorten the travel time to Mars to within 20 days. Copyright © 2016 Elsevier Ltd. All rights reserved.

Solid-state Marx based two-switch voltage modulator for the On-Line Isotope Mass Separator accelerator at the European Organization for Nuclear Research

NASA Astrophysics Data System (ADS)

Redondo, L. M.; Silva, J. Fernando; Canacsinh, H.; Ferrão, N.; Mendes, C.; Soares, R.; Schipper, J.; Fowler, A.

2010-07-01

A new circuit topology is proposed to replace the actual pulse transformer and thyratron based resonant modulator that supplies the 60 kV target potential for the ion acceleration of the On-Line Isotope Mass Separator accelerator, the stability of which is critical for the mass resolution downstream separator, at the European Organization for Nuclear Research. The improved modulator uses two solid-state switches working together, each one based on the Marx generator concept, operating as series and parallel switches, reducing the stress on the series stacked semiconductors, and also as auxiliary pulse generator in order to fulfill the target requirements. Preliminary results of a 10 kV prototype, using 1200 V insulated gate bipolar transistors and capacitors in the solid-state Marx circuits, ten stages each, with an electrical equivalent circuit of the target, are presented, demonstrating both the improved voltage stability and pulse flexibility potential wanted for this new modulator.

Comparison of marginal accuracy of castings fabricated by conventional casting technique and accelerated casting technique: an in vitro study.

PubMed

Reddy, S Srikanth; Revathi, Kakkirala; Reddy, S Kranthikumar

2013-01-01

Conventional casting technique is time consuming when compared to accelerated casting technique. In this study, marginal accuracy of castings fabricated using accelerated and conventional casting technique was compared. 20 wax patterns were fabricated and the marginal discrepancy between the die and patterns were measured using Optical stereomicroscope. Ten wax patterns were used for Conventional casting and the rest for Accelerated casting. A Nickel-Chromium alloy was used for the casting. The castings were measured for marginal discrepancies and compared. Castings fabricated using Conventional casting technique showed less vertical marginal discrepancy than the castings fabricated by Accelerated casting technique. The values were statistically highly significant. Conventional casting technique produced better marginal accuracy when compared to Accelerated casting. The vertical marginal discrepancy produced by the Accelerated casting technique was well within the maximum clinical tolerance limits. Accelerated casting technique can be used to save lab time to fabricate clinical crowns with acceptable vertical marginal discrepancy.

Nuclear processes in solar flares

NASA Technical Reports Server (NTRS)

Ramaty, R.

1982-01-01

The theory of solar gamma-ray line production is reviewed and new calculations of line production yields are presented. Observations, carried out with gamma-ray spectrometers on OSO-7, HEAO-1, HEAO-3 and SMM are reviewed and compared with theory. These observations provide direct evidence for nuclear reactions in flares and furnish unique information on particle acceleration and flare mechanisms.

A Conversation with William A. Fowler Part II

NASA Astrophysics Data System (ADS)

Greenberg, John

2005-06-01

Physicist William A.Fowler initiated an experimental program in nuclear astrophysics after World War II. He recalls here the Steady State versus Big Bang controversy and his celebrated collaboration with Fred Hoyle and Geoffrey and Margaret Burbidge on nucleosynthesis in stars. He also comments on the shift away from nuclear physics in universities to large accelerators and national laboratories.

Guidelines for Reviewers and the Editor at the Nuclear Safety Information Center.

ERIC Educational Resources Information Center

Whetsel, H. B.

The main purpose of this report is to help novice reviewers accelerate their apprenticeship at the Nuclear Safety Information Center, a computerized information service sponsored by the U.S. Atomic Energy Commission. Guidelines for reviewers are presented in Part 1; Part 2 contains guidelines for the novice editor. The goal of the reviewers and…

Initial results from a multiple monoenergetic gamma radiography system for nuclear security

NASA Astrophysics Data System (ADS)

O'Day, Buckley E.; Hartwig, Zachary S.; Lanza, Richard C.; Danagoulian, Areg

2016-10-01

The detection of assembled nuclear devices and concealed special nuclear materials (SNM) such as plutonium or uranium in commercial cargo traffic is a major challenge in mitigating the threat of nuclear terrorism. Currently available radiographic and active interrogation systems use ∼1-10 MeV bremsstrahlung photon beams. Although simple to build and operate, bremsstrahlung-based systems deliver high radiation doses to the cargo and to potential stowaways. To eliminate problematic issues of high dose, we are developing a novel technique known as multiple monoenergetic gamma radiography (MMGR). MMGR uses ion-induced nuclear reactions to produce two monoenergetic gammas for dual-energy radiography. This allows us to image the areal density and effective atomic number (Zeff) of scanned cargo. We present initial results from the proof-of-concept experiment, which was conducted at the MIT Bates Research and Engineering Center. The purpose of the experiment was to assess the capabilities of MMGR to measure areal density and Zeff of container cargo mockups. The experiment used a 3.0 MeV radiofrequency quadrupole accelerator to create sources of 4.44 MeV and 15.11 MeV gammas from the 11B(d,nγ)12C reaction in a thick natural boron target; the gammas are detected by an array of NaI(Tl) detectors after transmission through cargo mockups . The measured fluxes of transmitted 4.44 MeV and 15.11 MeV gammas were used to assess the areal density and Zeff. Initial results show that MMGR is capable of discriminating the presence of high-Z materials concealed in up to 30 cm of iron shielding from low- and mid-Z materials present in the cargo mockup.

The Naples University 3 MV tandem accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campajola, L.; Brondi, A.

2013-07-18

The 3 MV tandem accelerator of the Naples University is used for research activities and applications in many fields. At the beginning of operation (1977) the main utilization was in the field of nuclear physics. Later, the realization of new beam lines allowed the development of applied activities as radiocarbon dating, ion beam analysis, biophysics, ion implantation etc. At present, the availability of different ion sources and many improvements on the accelerator allow to run experiments in a wide range of subjects. An overview of the characteristics and major activities of the laboratory is presented.

Parasitic modes removal out of operating mode neighbourhood in the DAW accelerating structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andreev, V.G.; Belugin, V.M.; Esin, S.K.

1983-08-01

The disk and washer (DAW) accelerating structure finds its use in a number of new projects (PIGMI, SNQ etc ). It composes the main part of the accelerating structure of the meson factory now under construction in the Institute for Nuclear Research (INR), Moscow. It is known that the parasitic modes with azimuthal field variations exist at the operating mode region. In this report different methods of the parasitic modes frequency shift are considered. The main attention is given to the resonant methods, which are the most efficient.

Plutonium (TRU) transmutation and 233U production by single-fluid type accelerator molten-salt breeder (AMSB)

NASA Astrophysics Data System (ADS)

Furukawa, Kazuo; Kato, Yoshio; Chigrinov, Sergey E.

1995-09-01

For practical/industrial disposition of Pu(TRU) by accelerator facility, not only physical soundness and safety but also the following technological rationality should be required: (1) few R&D items including radiation damage, heat removal and material compatibility: (2) few operation/maintenance/processing works; (3) few reproduction of radioactivity; (4) effective energy production in parallel. This will be achieved by the new modification of Th-fertilizing Single-Fluid type Accelerator Molten-Salt Breeder (AMSB), by which a global nuclear energy strategy for next century might be prepared.

Nuclear Astrophysics in underground laboratories: the LUNA experiment

NASA Astrophysics Data System (ADS)

2017-11-01

One of the main ingredients of nuclear astrophysics is the knowledge of the thermonuclear reactions responsible for powering the stellar engine and for the synthesis of the chemical elements. At astrophysical energies the cross section of nuclear processes is extremely reduced by the effect of the Coulomb barrier. The low value of cross sections prevents their measurement at stellar energies on Earth surface and often extrapolations are needed. The Laboratory for Underground Nuclear Astrophysics (LUNA) is placed under the Gran Sasso mountain and thanks to the cosmic-ray background reduction provided by its position can investigate cross sections at energies close to the Gamow peak in stellar scenarios. Many crucial reactions involved in hydrogen burning has been measured directly at astrophysical energies with both the LUNA-50kV and the LUNA-400kV accelerators, and this intense work will continue with the installation of a MV machine able to explore helium and carbon burnings. Based on this progress, currently there are efforts in several countries to construct new underground accelerators. In this talk, the typical techniques adopted in underground nuclear astrophysics will be described and the most relevant results achieved by LUNA will be reviewed. The exciting science that can be probed with the new facilities will be highlighted.

Physics of the saturation of particle acceleration in relativistic magnetic reconnection

NASA Astrophysics Data System (ADS)

Kagan, Daniel; Nakar, Ehud; Piran, Tsvi

2018-05-01

We investigate the saturation of particle acceleration in relativistic reconnection using two-dimensional particle-in-cell simulations at various magnetizations σ. We find that the particle energy spectrum produced in reconnection quickly saturates as a hard power law that cuts off at γ ≈ 4σ, confirming previous work. Using particle tracing, we find that particle acceleration by the reconnection electric field in X-points determines the shape of the particle energy spectrum. By analysing the current sheet structure, we show that physical cause of saturation is the spontaneous formation of secondary magnetic islands that can disrupt particle acceleration. By comparing the size of acceleration regions to the typical distance between disruptive islands, we show that the maximum Lorentz factor produced in reconnection is γ ≈ 5σ, which is very close to what we find in our particle energy spectra. We also show that the dynamic range in Lorentz factor of the power-law spectrum in reconnection is ≤40. The hardness of the power law combined with its narrow dynamic range implies that relativistic reconnection is capable of producing the hard narrow-band flares observed in the Crab nebula but has difficulty producing the softer broad-band prompt gamma-ray burst emission.

Desirable limits of accelerative forces in a space-based materials processing facility

NASA Technical Reports Server (NTRS)

Naumann, Robert J.

1990-01-01

There are three categories of accelerations to be encountered on orbiting spacecraft: (1) quasi-steady accelerations, caused by atmospheric drag or by gravity gradients, 10(exp -6) to 10(exp -7) g sub o; (2) transient accelerations, caused by movements of the astronauts, mass translocations, landing and departure of other spacecraft, etc.; and (3) oscillary accelerations, caused by running machinery (fans, pumps, generators). Steady accelerations cause continuing displacements; transients cause time-limited displacements. The important aspect is the area under the acceleration curve, measured over a certain time interval. Note that this quantity is not equivalent to a velocity because of friction effects. Transient motions are probably less important than steady accelerations because they only produce constant displacements. If the accelerative forces were not equal and opposite, the displacement would increase with time. A steady acceleration will produce an increasing velocity of a particle, but eventually an equilibrium value will be reached where drag and acceleration forces are equal. From then on, the velocity will remain constant, and the displacement will increase linearly with time.

Closed DTU fuel cycle with Np recycle and waste transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beller, D.E.; Sailor, W.C.; Venneri, F.

1999-09-01

A nuclear energy scenario for the 21st century that included a denatured thorium-uranium-oxide (DTU) fuel cycle and new light water reactors (LWRs) supported by accelerator-driven transmutation of waste (ATW) systems was previously described. This coupled system with the closed DTU fuel cycle provides several improvements beyond conventional LWR (CLWR) (once-through, UO{sub 2} fuel) nuclear technology: increased proliferation resistance, reduced waste, and efficient use of natural resources. However, like CLWR fuel cycles, the spent fuel in the first one-third core discharged after startup contains higher-quality Pu than the equilibrium fuel cycle. To eliminate this high-grade Pu, Np is separated and recycledmore » with Th and U--rather than with higher actinides [(HA) including Pu]. The presence of Np in the LWR feed greatly increases the production of {sup 238}Pu so that a few kilograms of Pu generated enough alpha-decay heat that the separated Pu is highly resistant to proliferation. This alternate process also simplifies the pyrochemical separation of fuel elements (Th and U) from HAs. To examine the advantages of this concept, the authors modeled a US deployment scenario for nuclear energy that includes DTU-LWRs plus ATW`s to burn the actinides produced by these LWRs and to close the back-end of the DTU fuel cycle.« less

Detection of fissionable materials in cargoes using monochromatic photon radiography

NASA Astrophysics Data System (ADS)

Danagoulian, Areg; Lanza, Richard; O'Day, Buckley; LNSP Team

2015-04-01

The detection of Special Nuclear Materials (e.g. Pu and U) and nuclear devices in the commercial cargo traffic is one of the challenges posed by the threat of nuclear terrorism. Radiography and active interrogation of heavily loaded cargoes require ~ 1 - 10MeV photons for penetration. In a proof-of-concept system under development at MIT, the interrogating monochromatic photon beam is produced via a 11B(d , nγ) 12C reaction. To achieve this, a boron target is used along with the 3 MeV d+ RFQ accelerator at MIT-Bates. The reactions results in the emission of very narrow 4.4 MeV and 15.1 MeV gammas lines. The photons, after traversing the cargo, are detected by an array of NaI(Tl) detectors. A spectral analysis of the transmitted gammas allows to independently determine the areal density and the atomic number (Z) of the cargo. The proposed approach could revolutionize cargo inspection, which, in its current fielded form has to rely on simple but high dose bremsstrahlung sources. Use of monochromatic sources would significantly reduce the necessary dose and allow for better determination of the cargo's atomic number. The general methodology will be described and the preliminary results from the proof-of-concept system will be presented and discussed. Supported by NSF/DNDO Collaborative Research ARI-LA Award ECCS-1348328.

Therapeutic Effect of Topical Administration of SN50, an Inhibitor of Nuclear Factor-κB, in Treatment of Corneal Alkali Burns in Mice

PubMed Central

Saika, Shizuya; Miyamoto, Takeshi; Yamanaka, Osamu; Kato, Tadashi; Ohnishi, Yoshitaka; Flanders, Kathleen C.; Ikeda, Kazuo; Nakajima, Yuji; Kao, Winston W.-Y.; Sato, Misako; Muragaki, Yasuteru; Ooshima, Akira

2005-01-01

We evaluated the therapeutic efficacy of topical administration of SN50, an inhibitor of nuclear factor-κB, in a corneal alkali burn model in mice. An alkali burn was produced with 1 N NaOH in the cornea of C57BL/6 mice under general anesthesia. SN50 (10 μg/μl) or vehicle was topically administered daily for up to 12 days. The eyes were processed for histological or immunohistochemical examination after bromodeoxyuridine labeling or for semiquantification of cytokine mRNA. Topical SN50 suppressed nuclear factor-κB activation in local cells and reduced the incidence of epithelial defects/ulceration in healing corneas. Myofibroblast generation, macrophage invasion, activity of matrix metalloproteinases, basement membrane destruction, and expression of cytokines were all decreased in treated corneas compared with controls. To elucidate the role of tumor necrosis factor (TNF)-α in epithelial cell proliferation, we performed organ culture of mouse eyes with TNF-α, SN50, or an inhibitor of c-Jun N-terminal kinase (JNK) and examined cell proliferation in healing corneal epithelium in TNF-α−/− mice treated with SN50. An acceleration of epithelial cell proliferation by SN50 treatment was found to depend on TNF-α/JNK signaling. In conclusion, topical application of SN50 is effective in treating corneal alkali burns in mice. PMID:15855640

Optimization of the Efficiency of a Neutron Detector to Measure (α, n) Reaction Cross-Section

NASA Astrophysics Data System (ADS)

Perello, Jesus; Montes, Fernando; Ahn, Tony; Meisel, Zach; Joint InstituteNuclear Astrophysics Team

2015-04-01

Nucleosynthesis, the origin of elements, is one of the greatest mysteries in physics. A recent particular nucleosynthesis process of interest is the charge-particle process (cpp). In the cpp, elements form by nuclear fusion reactions during supernovae. This process of nuclear fusion, (α,n), will be studied by colliding beam elements produced and accelerated at the National Superconducting Cyclotron Laboratory (NSCL) to a helium-filled cell target. The elements will fuse with α (helium nuclei) and emit neutrons during the reaction. The neutrons will be detected for a count of fused-elements, thus providing us the probability of such reactions. The neutrons will be detected using the Neutron Emission Ratio Observer (NERO). Currently, NERO's efficiency varies for neutrons at the expected energy range (0-12 MeV). To study (α,n), NERO's efficiency must be near-constant at these energies. Monte-Carlo N-Particle Transport Code (MCNP6), a software package that simulates nuclear processes, was used to optimize NERO configuration for the experiment. MCNP6 was used to simulate neutron interaction with different NERO configurations at the expected neutron energies. By adding additional 3He detectors and polyethylene, a near-constant efficiency at these energies was obtained in the simulations. With the new NERO configuration, study of the (α,n) reactions can begin, which may explain how elements are formed in the cpp. SROP MSU, NSF, JINA, McNair Society.

Fission Product Yields from {sup 232}Th, {sup 238}U, and {sup 235}U Using 14 MeV Neutrons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierson, B.D., E-mail: bpnuke@umich.edu; Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA 99352; Greenwood, L.R.

Neutron-induced fission yield studies using deuterium-tritium fusion-produced 14 MeV neutrons have not yet directly measured fission yields from fission products with half-lives on the order of seconds (far from the line of nuclear stability). Fundamental data of this nature are important for improving and validating the current models of the nuclear fission process. Cyclic neutron activation analysis (CNAA) was performed on three actinide targets–thorium-oxide, depleted uranium metal, and highly enriched uranium metal–at the University of Michigan's Neutron Science Laboratory (UM-NSL) using a pneumatic system and Thermo-Scientific D711 accelerator-based fusion neutron generator. This was done to measure the fission yields ofmore » short-lived fission products and to examine the differences between the delayed fission product signatures of the three actinides. The measured data were compared against previously published results for {sup 89}Kr, −90, and −92 and {sup 138}Xe, −139, and −140. The average percent deviation of the measured values from the Evaluated Nuclear Data Files VII.1 (ENDF/B-VII.1) for thorium, depleted-uranium, and highly-enriched uranium were −10.2%, 4.5%, and −12.9%, respectively. In addition to the measurements of the six known fission products, 23 new fission yield measurements from {sup 84}As to {sup 146}La are presented.« less

The neutrons for science facility at SPIRAL-2

NASA Astrophysics Data System (ADS)

Ledoux, X.; Aïche, M.; Avrigeanu, M.; Avrigeanu, V.; Balanzat, E.; Ban-d'Etat, B.; Ban, G.; Bauge, E.; Bélier, G.; Bém, P.; Borcea, C.; Caillaud, T.; Chatillon, A.; Czajkowski, S.; Dessagne, P.; Doré, D.; Fischer, U.; Frégeau, M. O.; Grinyer, J.; Guillous, S.; Gunsing, F.; Gustavsson, C.; Henning, G.; Jacquot, B.; Jansson, K.; Jurado, B.; Kerveno, M.; Klix, A.; Landoas, O.; Lecolley, F. R.; Lecouey, J. L.; Majerle, M.; Marie, N.; Materna, T.; Mrázek, J.; Negoita, F.; Novák, J.; Oberstedt, S.; Oberstedt, A.; Panebianco, S.; Perrot, L.; Plompen, A. J. M.; Pomp, S.; Prokofiev, A. V.; Ramillon, J. M.; Farget, F.; Ridikas, D.; Rossé, B.; Sérot, O.; Simakov, S. P.; Šimečková, E.; Štefánik, M.; Sublet, J. C.; Taïeb, J.; Tarrío, D.; Tassan-Got, L.; Thfoin, I.; Varignon, C.

2017-09-01

Numerous domains, in fundamental research as well as in applications, require the study of reactions induced by neutrons with energies from few MeV up to few tens of MeV. Reliable measurements also are necessary to improve the evaluated databases used by nuclear transport codes. This energy range covers a large number of topics like transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors. A new facility called Neutrons For Science (NFS) is being built for this purpose on the GANIL site at Caen (France). NFS is composed of a pulsed neutron beam for time-of-flight facility as well as irradiation stations for cross-section measurements. Neutrons will be produced by the interaction of deuteron and proton beams, delivered by the SPIRAL-2 linear accelerator, with thick or thin converters made of beryllium or lithium. Continuous and quasi-mono-energetic spectra will be available at NFS up to 40 MeV. In this fast energy region, the neutron flux is expected to be up to 2 orders of magnitude higher than at other existing time-of-flight facilities. In addition, irradiation stations for neutron-, proton- and deuteron-induced reactions will allow performing cross-section measurements by the activation technique. After a description of the facility and its characteristics, the experiments to be performed in the short and medium term will be presented.

The use of aluminum nitride to improve Aluminum-26 Accelerator Mass Spectrometry measurements and production of Radioactive Ion Beams

NASA Astrophysics Data System (ADS)

Janzen, Meghan S.; Galindo-Uribarri, Alfredo; Liu, Yuan; Mills, Gerald D.; Romero-Romero, Elisa; Stracener, Daniel W.

2015-10-01

We present results and discuss the use of aluminum nitride as a promising source material for Accelerator Mass Spectrometry (AMS) and Radioactive Ion Beams (RIBs) science applications of 26Al isotopes. The measurement of 26Al in geological samples by AMS is typically conducted on Al2O3 targets. However, Al2O3 is not an ideal source material because it does not form a prolific beam of Al- required for measuring low-levels of 26Al. Multiple samples of aluminum oxide (Al2O3), aluminum nitride (AlN), mixed Al2O3-AlN as well as aluminum fluoride (AlF3) were tested and compared using the ion source test facility and the stable ion beam (SIB) injector platform at the 25-MV tandem electrostatic accelerator at Oak Ridge National Laboratory. Negative ion currents of atomic and molecular aluminum were examined for each source material. It was found that pure AlN targets produced substantially higher beam currents than the other materials and that there was some dependence on the exposure of AlN to air. The applicability of using AlN as a source material for geological samples was explored by preparing quartz samples as Al2O3 and converting them to AlN using a carbothermal reduction technique, which involved reducing the Al2O3 with graphite powder at 1600 °C within a nitrogen atmosphere. The quartz material was successfully converted to AlN. Thus far, AlN proves to be a promising source material and could lead towards increasing the sensitivity of low-level 26Al AMS measurements. The potential of using AlN as a source material for nuclear physics is also very promising by placing 26AlN directly into a source to produce more intense radioactive beams of 26Al.

SPES and the neutron facilities at Laboratori Nazionali di Legnaro

NASA Astrophysics Data System (ADS)

Silvestrin, L.; Bisello, D.; Esposito, J.; Mastinu, P.; Prete, G.; Wyss, J.

2016-03-01

The SPES Radioactive Ion Beam (RIB) facility, now in the construction phase at INFN-LNL, has the aim to provide high-intensity and high-quality beams of neutron-rich nuclei for nuclear physics research as well as to develop an interdisciplinary research center based on the cyclotron proton beam. The SPES system is based on a dual-exit high-current cyclotron, with tunable proton beam energy 35-70MeV and 0.20-0.75mA. The first exit is used as proton driver to supply an ISOL system with an UCx Direct Target able to sustain a power of 10kW. The expected fission rate in the target is of the order of 10^{13} fissions per second. The exotic isotopes will be re-accelerated by the ALPI superconducting LINAC at energies of 10 A MeV and higher, for masses around A=130 amu, with an expected beam intensity of 10^7 - 10^9 pps. The second exit will be used for applied physics: radioisotope production for medicine and neutrons for material studies. Fast neutron spectra will be produced by the proton beam interaction with a conversion target. A production rate in excess of 10^{14} n/s can be achieved: this opens up the prospect of a high-flux neutron irradiation facility (NEPIR) to produce both discrete and continuous energy neutrons. A direct proton beam line is also envisaged. NEPIR and the direct proton line would dramatically increase the wide range of irradiation facilities presently available at LNL. We also present LENOS, a proposed project dedicated to accurate neutron cross-sections measurements using intense, well-characterized, broad energy neutron beams. Other activities already in operation at LNL are briefly reviewed: the SIRAD facility for proton and heavy-ion irradiation at the TANDEM-ALPI accelerator and the BELINA test facility at CN van de Graaff accelerator.

The use of aluminum nitride to improve Aluminum-26 Accelerator Mass Spectrometry measurements and production of Radioactive Ion Beams

DOE PAGES

Janzen, Meghan S.; Galindo-Uribarri, Alfredo; Liu, Yuan; ...

2015-06-29

In this paper, we present results and discuss the use of aluminum nitride as a promising source material for Accelerator Mass Spectrometry (AMS) and Radioactive Ion Beams (RIBs) science applications of 26Al isotopes. The measurement of 26Al in geological samples by AMS is typically conducted on Al 2O 3 targets. However, Al 2O 3 is not an ideal source material because it does not form a prolific beam of Al - required for measuring low-levels of 26Al. Multiple samples of aluminum oxide (Al 2O 3), aluminum nitride (AlN), mixed Al 2O 3–AlN as well as aluminum fluoride (AlF 3) weremore » tested and compared using the ion source test facility and the stable ion beam (SIB) injector platform at the 25-MV tandem electrostatic accelerator at Oak Ridge National Laboratory. Negative ion currents of atomic and molecular aluminum were examined for each source material. It was found that pure AlN targets produced substantially higher beam currents than the other materials and that there was some dependence on the exposure of AlN to air. The applicability of using AlN as a source material for geological samples was explored by preparing quartz samples as Al 2O 3 and converting them to AlN using a carbothermal reduction technique, which involved reducing the Al 2O 3 with graphite powder at 1600°C within a nitrogen atmosphere. The quartz material was successfully converted to AlN. Thus far, AlN proves to be a promising source material and could lead towards increasing the sensitivity of low-level 26Al AMS measurements. In conclusion, the potential of using AlN as a source material for nuclear physics is also very promising by placing 26AlN directly into a source to produce more intense radioactive beams of 26Al.« less

Photonuclear-based Detection of Nuclear Smuggling in Cargo Containers

NASA Astrophysics Data System (ADS)

Jones, J. L.; Haskell, K. J.; Hoggan, J. M.; Norman, D. R.; Yoon, W. Y.

2003-08-01

The Idaho National Engineering and Environmental Laboratory (INEEL) and the Los Alamos National Laboratory (LANL) have performed experiments in La Honda, California and at the Idaho Accelerator Center in Pocatello, Idaho to assess and develop a photonuclear-based detection system for shielded nuclear materials in cargo containers. The detection system, measuring photonuclear-related neutron emissions, is planned for integration with the ARACOR Eagle Cargo Container Inspection System (Sunnyvale, CA). The Eagle Inspection system uses a nominal 6-MeV electron accelerator and operates with safe radiation exposure limits to both container stowaways and to its operators. The INEEL has fabricated custom-built, helium-3-based, neutron detectors for this inspection application and is performing an experimental application assessment. Because the Eagle Inspection system could not be moved to LANL where special nuclear material was available, the response of the Eagle had to be determined indirectly so as to support the development and testing of the detection system. Experiments in California have successfully matched the delayed neutron emission performance of the ARACOR Eagle with that of the transportable INEEL electron accelerator (i.e., the Varitron) and are reported here. A demonstration test is planned at LANL using the Varitron and shielded special nuclear materials within a cargo container. Detector results are providing very useful information regarding the challenges of delayed neutron counting near the photofission threshold energy of 5.5 - 6.0 MeV, are identifying the possible utilization of prompt neutron emissions to allow enhanced signal-to-noise measurements, and are showing the overall benefits of using higher electron beam energies.

Smoot Cosmology Group

Science.gov Websites

Links We bring the universe to you! University of California Berkeley Cosmology Group Lawrence Computational Cosmology Center Institute for Nuclear & Particle Astrophysics Supernova Acceleration Probe

GPU-accelerated computational tool for studying the effectiveness of asteroid disruption techniques

NASA Astrophysics Data System (ADS)

Zimmerman, Ben J.; Wie, Bong

2016-10-01

This paper presents the development of a new Graphics Processing Unit (GPU) accelerated computational tool for asteroid disruption techniques. Numerical simulations are completed using the high-order spectral difference (SD) method. Due to the compact nature of the SD method, it is well suited for implementation with the GPU architecture, hence solutions are generated at orders of magnitude faster than the Central Processing Unit (CPU) counterpart. A multiphase model integrated with the SD method is introduced, and several asteroid disruption simulations are conducted, including kinetic-energy impactors, multi-kinetic energy impactor systems, and nuclear options. Results illustrate the benefits of using multi-kinetic energy impactor systems when compared to a single impactor system. In addition, the effectiveness of nuclear options is observed.

10 CFR 32.1 - Purpose and scope.

Code of Federal Regulations, 2010 CFR

2010-01-01

... recognized Indian Tribes with respect to accelerator-produced radioactive material or discrete sources of... transfer items containing accelerator-produced radioactive material or discrete sources of radium-226 for... radioactive material or discrete sources of radium-226 on August 8, 2009, or earlier as noticed by the NRC...

[Experimental nuclear physics]. Annual report 1988

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1988-05-01

This is the May 1988 annual report of the Nuclear Physics Laboratory of the University of Washington. It contains chapters on astrophysics, giant resonances, heavy ion induced reactions, fundamental symmetries, polarization in nuclear reactions, medium energy reactions, accelerator mass spectrometry (AMS), research by outside users, Van de Graaff and ion sources, the Laboratory`s booster linac project work, instrumentation, and computer systems. An appendix lists Laboratory personnel, Ph.D. degrees granted in the 1987-88 academic year, and publications. Refs., 27 figs., 4 tabs.

[Experimental nuclear physics]. Annual report 1989

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1989-04-01

This is the April 1989 annual report of the Nuclear Physics Labortaory of the University of Washington. It contains chapters on astrophysics, giant resonances, heavy ion induced reactions, fundamental symmetries, polarization in nuclear reactions, medium energy reactions, accelerator mass spectrometry (AMS), research by outside users, Van de Graaff and ion sources, computer systems, instrumentation, and the Laboratory`s booster linac work. An appendix lists Laboratory personnel, Ph.D. degrees granted in the 1988-1989 academic year, and publications. Refs., 23 figs., 3 tabs.

RAMI modeling of selected balance of plant systems for the proposed Accelerator Production of Tritium (APT) project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Radder, J.A.; Cramer, D.S.

1997-06-01

In order to meet Department of Energy (DOE) Defense Program requirements for tritium in the 2005-2007 time frame, new production capability must be made available. The Accelerator Production of Tritium (APT) Plant is being considered as an alternative to nuclear reactor production of tritium, which has been the preferred method in the past. The proposed APT plant will use a high-power proton accelerator to generate thermal neutrons that will be captured in {sup 3}He to produce tritium (3H). It is expected that the APT Plant will be built and operated at the DOE`s Savannah River Site (SRS) in Aiken, Southmore » Carolina. Discussion is focused on Reliability, Availability, Maintainability, and Inspectability (RAMI) modeling of recent conceptual designs for balance of plant (BOP) systems in the proposed APT Plant. In the conceptual designs for balance of plant (BOP) systems in the proposed APT Plant. In the conceptual design phase, system RAMI estimates are necessary to identify the best possible system alternative and to provide a valid picture of the cost effectiveness of the proposed system for comparison with other system alternatives. RAMI estimates in the phase must necessarily be based on generic data. The objective of the RAMI analyses at the conceptual design stage is to assist the designers in achieving an optimum design which balances the reliability and maintainability requirements among the subsystems and components.« less

Hadron Therapy in Latin America

NASA Astrophysics Data System (ADS)

Kreiner, A. J.; Bergueiro, J.; Burlon, A. A.; Di Paolo, H.; Castell, W.; Thatar Vento, V.; Levinas, P.; Cartelli, D.; Kesque, J. M.; Valda, A. A.; Ilardo, J. C.; Baldo, M.; Erhardt, J.; Debray, M. E.; Somacal, H. R.; Minsky, D. M.; Estrada, L.; Hazarabedian, A.; Johann, F.; Suarez Sandin, J. C.; Igarzabal, M.; Huck, H.; Repetto, M.; Obligado, M.; Lell, J.; Padulo, J.; Herrera, M.; Gonzalez, S. R.; Capoulat, M. E.; Davidson, J.; Davidson, M.

2010-08-01

The use of proton and heavy ion beams for radiotherapy is a well established cancer treatment modality in the first world, which is becoming increasingly widespread, due to its clear advantages over conventional photon-based treatments. This strategy is suitable when the tumor is spatially well localized. Also the use of neutrons has tradition. Here Boron Neutron Capture Therapy (BNCT) stands out, though on a much smaller scale, being a promising alternative for tumors which are diffuse and infiltrating. On this sector, so far only nuclear reactors have been used as neutron sources. In this paper we briefly describe the situation in Latin America and in particular we discuss the present status of an ongoing project to develop a folded Tandem-ElectroStatic-Quadrupole (TESQ) accelerator for Accelerator-Based (AB)-Boron Neutron Capture Therapy (BNCT) at the Atomic Energy Commission of Argentina. The project goal is a machine capable of delivering 30 mA of 2.4 MeV protons to be used in conjunction with a neutron production target based on the 7Li(p,n)7Be reaction. These are the specifications needed to produce sufficiently intense and clean epithermal neutron beams to perform BNCT for deep-seated tumors in less than an hour. The machine being currently designed and constructed is a folded TESQ with a terminal at 0.6 MV as a smaller scale prototype. Since the concept is modular the same structure will be used for the 1.2 MV final accelerator.

Development of high flux thermal neutron generator for neutron activation analysis

NASA Astrophysics Data System (ADS)

Vainionpaa, Jaakko H.; Chen, Allan X.; Piestrup, Melvin A.; Gary, Charles K.; Jones, Glenn; Pantell, Richard H.

2015-05-01

The new model DD110MB neutron generator from Adelphi Technology produces thermal (<0.5 eV) neutron flux that is normally achieved in a nuclear reactor or larger accelerator based systems. Thermal neutron fluxes of 3-5 · 107 n/cm2/s are measured. This flux is achieved using four ion beams arranged concentrically around a target chamber containing a compact moderator with a central sample cylinder. Fast neutron yield of ∼2 · 1010 n/s is created at the titanium surface of the target chamber. The thickness and material of the moderator is selected to maximize the thermal neutron flux at the center. The 2.5 MeV neutrons are quickly thermalized to energies below 0.5 eV and concentrated at the sample cylinder. The maximum flux of thermal neutrons at the target is achieved when approximately half of the neutrons at the sample area are thermalized. In this paper we present simulation results used to characterize performance of the neutron generator. The neutron flux can be used for neutron activation analysis (NAA) prompt gamma neutron activation analysis (PGNAA) for determining the concentrations of elements in many materials. Another envisioned use of the generator is production of radioactive isotopes. DD110MB is small enough for modest-sized laboratories and universities. Compared to nuclear reactors the DD110MB produces comparable thermal flux but provides reduced administrative and safety requirements and it can be run in pulsed mode, which is beneficial in many neutron activation techniques.

AMS with light nuclei at small accelerators

NASA Astrophysics Data System (ADS)

Stan-Sion, C.; Enachescu, M.

2017-06-01

AMS applications with lighter nuclei are presented. It will be shown how Carbon-14, Boron-10, Beryllium-10, and Tritium-3 can be used to provide valuable information in forensic science, environmental physics, nuclear pollution, in material science and for diagnose of the plasma confinement in fusion reactors. Small accelerators are reliable, efficient and possess the highest ion beam transmissions that confer high precision in measurements.

Calculations of skyshine from an intense portable electron linac

DOE Office of Scientific and Technical Information (OSTI.GOV)

Estes, G.P.; Hughes, H.G.; Fry, D.A.

1994-12-31

The MCNP Monte carlo code has been used at Los Alamos to calculate skyshine and terrain albedo efects from an intense portable electron linear accelerator that is to be used by the Russian Federation to radiograph nuclear weapons that may have been damaged by accidents. Relative dose rate profiles have been calculated. The design of the accelerator, along with a diagram, is presented.

Closed tubes preparation of graphite for high-precision AMS radiocarbon analysis

NASA Astrophysics Data System (ADS)

Hajdas, I.; Michczynska, D.; Bonani, G.; Maurer, M.; Wacker, L.

2009-04-01

Radiocarbon dating is an established tool applied in Geochronology. Technical developments of Accelerator Mass Spectrometry AMS, which allow measurements of samples containing less than 1 mg of carbon, opened opportunities for new applications. Moreover, high resolution records of the past changes require high-resolution chronologies i.e. sampling for 14C dating. In result, the field of applications is rapidly expanding and number of radiocarbon analysis is growing rapidly. Nowadays dedicated 14C AMS machines have great capacity for analysis but in order to keep up with the demand for analysis and provide the results as fast as possible a very efficient way of sample preparation is required. Sample preparation for 14C AMS analysis consists of two steps: separation of relevant carbon from the sample material (removing contamination) and preparation of graphite for AMS analysis. The last step usually involves reaction of CO2 with H2, in the presence of metal catalyst (Fe or Co) of specific mesh size heated to 550-625°C, as originally suggested by Vogel et al. (1984). Various graphitization systems have been built in order to fulfil the requirement of sample quality needed for high-precision radiocarbon data. In the early 90ties another method has been proposed (Vogel 1992) and applied by few laboratories mainly for environmental or biomedical samples. This method uses TiH2 as a source of H2 and can be easily and flexibly applied to produce graphite. Sample of CO2 is frozen in to the tube containing pre-conditioned Zn/TiH2 and Fe catalyst. Torch sealed tubes are then placed in the stepwise heated oven at 500/550°C and left to react for several hours. The greatest problem is the lack of control of the reaction completeness and considerable fractionation. However, recently reported results (Xu et al. 2007) suggest that high precision dating using graphite produced in closed tubes might be possible. We will present results of radiocarbon dating of the set of standards and secondary IAEA standards to demonstrate to what level this method can be used for high precision radiocarbon dating. References Vogel JS. 1992. Rapid Production of Graphite without Contamination for Biomedical Ams. Radiocarbon 34: 344-350. Vogel JS, Southon JR, Nelson DE, and Brown TA. 1984. Performance of Catalytically Condensed Carbon for Use in Accelerator Mass-Spectrometry. Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms 233: 289-293. Xu X, Trumbore SE, Zheng S, Southon JR, McDuffee KE, Luttgen M, and Liu JC. 2007. Modifying a sealed tube zinc reduction method for preparation of AMS graphite targets: Reducing background and attaining high precision. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms Accelerator Mass Spectrometry - Proceedings of the Tenth International Conference on Accelerator Mass Spectrometry 259: 320-329.