WorldWideScience

Sample records for exapprox 100-200 mev

  1. Deutsch 100, 200, 300.

    Science.gov (United States)

    Manitoba Dept. of Education, Winnipeg.

    Manitoba's curriculum guide for German 100, 200, and 300 is designed to (1) make teachers of these courses aware of the official policy concerning the nature, goals, and objectives of the courses and approved teaching materials, and (2) provide instructional guidelines. The guide provides information about three sets of teaching materials from…

  2. 76 FR 72858 - Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500...

    Science.gov (United States)

    2011-11-28

    ... Model 737-100, -200, -300, -400, and -500 series airplanes, a one-time detailed inspection is added to... Information Initial Compliance Time (i) For all Model 737-100, -200, -200C, -300, -400, and -500 series... by paragraph (r) of this AD. If any fastener is missing, before further flight, repair using a method...

  3. Highly reusable space transportation: Approaches for reducing ETO launch costs to $100 - $200 per pound of payload

    Science.gov (United States)

    Olds, John R.

    1995-01-01

    The Commercial Space Transportation Study (CSTS) suggests that considerable market expansion in earth-to-orbit transportation would take place if current launch prices could be reduced to around $400 per pound of payload. If these low prices can be achieved, annual payload delivered to low earth orbit (LEO) is predicted to reach 6.7 million pounds. The primary market growth will occur in communications, government missions, and civil transportation. By establishing a cost target of $100-$200 per pound of payload for a new launch system, the Highly Reusable Space Transportation (HRST) program has clearly set its sights on removing the current restriction on market growth imposed by today's high launch costs. In particular, achieving the goal of $100-$200 per pound of payload will require significant coordinated efforts in (1) marketing strategy development, (2) business planning, (3) system operational strategy, (4) vehicle technical design, and (5) vehicle maintenance strategy.

  4. X-ray study of the structure of polyethylene at the scale of 100-200 Angstrom; Etude par rayons X dela structure du polyethylene a l'echelle de 100-200 Angstrom

    Energy Technology Data Exchange (ETDEWEB)

    Belbeoch nee Goldsztein, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-06-15

    Information on the structure of polyethylene is deduced from a comparison of the results obtained by central diffusion and by other X-ray methods. The structure depends on the thermal and mechanical treatment to which the samples are subjected, as well as on the observation temperature. The central diffusion due to the heterogeneity of the material at the scale of 100-200 Angstrom is bound up with the presence of both the amorphous and crystalline phases. Stretched polythene shows a more or less regular succession of orderly and disorderly regions. When released it has a structure of recrystallisation preceded by 'amorphization'. (author) [French] Les informations sur la structure du polyethylene sont deduites de la confrontation des resultats obtenus par la diffusion centrale et par d'autres methodes de rayons X. La structure depend des traitements thermiques et mecaniques subis par les echantillons ainsi que la temperature d'observation. La diffusion centrale due a l'existence d'heterogeneites de la matiere a l'echelle 100-200 Angstrom est lie a la presence des deux phases amorphe et cristallisee. Le polyethylene etire comporte une succession plus ou moins reguliere de domaines ordonnes et desordonnes. Le polyethylene relaxe a une structure de recristallisation precedee d'une 'amorphisation'. (auteur)

  5. X-ray study of the structure of polyethylene at the scale of 100-200 Angstrom

    International Nuclear Information System (INIS)

    Belbeoch nee Goldsztein, B.

    1958-06-01

    Information on the structure of polyethylene is deduced from a comparison of the results obtained by central diffusion and by other X-ray methods. The structure depends on the thermal and mechanical treatment to which the samples are subjected, as well as on the observation temperature. The central diffusion due to the heterogeneity of the material at the scale of 100-200 Angstrom is bound up with the presence of both the amorphous and crystalline phases. Stretched polythene shows a more or less regular succession of orderly and disorderly regions. When released it has a structure of recrystallisation preceded by 'amorphization'. (author) [fr

  6. Hydrogen storage performances of LaMg{sub 11}Ni + x wt% Ni (x = 100, 200) alloys prepared by mechanical milling

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yanghuan, E-mail: zhangyh59@sina.com [Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010 (China); Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081 (China); Wang, Haitao [Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010 (China); Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081 (China); Zhai, Tingting; Yang, Tai; Yuan, Zeming; Zhao, Dongliang [Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081 (China)

    2015-10-05

    Highlights: • Amorphous and nanostructured alloys were prepared by mechanical milling. • The maximum discharge capacity of ball milled alloys reaches to 1053.5 mA h/g. • The addition of Ni significantly increases the discharge capacity. • Increasing milling time reduces the kinetic performances of ball milled alloys. - Abstract: In order to improve the hydrogen storage performances of Mg-based materials, LaMg{sub 11}Ni alloy was prepared by vacuum induction melting. Then the nanocrystalline/amorphous LaMg{sub 11}Ni + x wt% Ni (x = 100, 200) hydrogen storage alloys were synthesized by ball milling technology. The structure characterizations of the alloys were carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical hydrogen storage characteristics were tested by using programmed control battery testing system. The electrochemical impedance spectra (EIS), potentiodynamic polarization curves and potential-step curves were also plotted by an electrochemical workstation (PARSTAT 2273). The results indicate that the as-milled alloys exhibit a nanocrystalline and amorphous structure, and the amorphization degree of the alloys visibly increases with extending milling time. Prolonging the milling duration markedly enhances the electrochemical discharge capacity and cyclic stability of the alloys. The electrochemical kinetics, including high rate discharge ability (HRD), charge transfer rate, limiting current density (I{sub L}), hydrogen diffusion coefficient (D), monotonously decrease with milling time prolonging.

  7. Hydrogen storage thermodynamics and kinetics of LaMg11Ni + x wt.% Ni (x = 100, 200) alloys synthesized by mechanical milling

    International Nuclear Information System (INIS)

    Zhang, Yanghuan; Jia, Zhichao; Central Iron and Steel Research Institute, Beijing; Yuan, Zeming; Qi, Yan; Zhao, Dongliang; Hou, Zhonghui

    2016-01-01

    LaMg 11 Ni + x wt.% Ni (x = 100, 200) composite hydrogen storage alloys with a nanocrystalline/amorphous structure were synthesized using ball milling technology. The effects of Ni content and milling time on hydrogen storage thermodynamics and dynamics of the alloys were investigated systematically. The hydrogen desorption properties were assessed using a Sieverts apparatus and differential scanning calorimetry. The thermodynamic parameters for the hydrogen absorption and desorption were calculated using the Van't Hoff equation. The hydrogen desorption activation energies of the hydrogenated alloys were also estimated by Arrhenius and Kissinger methods. Results indicate that the amount of Ni added has no effect on the thermodynamics of the alloys, but it significantly improves their absorption and desorption kinetics. Furthermore, the milling time has a great influence on the hydrogen storage properties. To be specific, the hydrogen absorption capacities reach the maximum values with the variation of milling time, and the hydrogen desorption activation energy obviously decreases with increasing milling time.

  8. Diffusion coefficients for Tl, Pb, Cd, In, Zn, Bi, As, Mo and Sb in hydrous rhyolite at 100-200 MPa

    Science.gov (United States)

    Berlo, Kim; Brooker, Richard; Wilke, Max

    2014-05-01

    A series of experiments have been conducted to determine the diffusivities of Tl, Pb, Cd, In, Zn, Bi, As, Mo and Sb in hydrous rhyolitic melt. Diffusion experiments used two adjoining glass cylinder of the same hydrous composition, one doped with the elements of interest at ~ 100 ppm. These couples were rapidly heated to 850, 1000 and 1150°C at 100-200 MPa for a few hours. After quenching the sectioned charges were analyzed by both synchrotron XRF (The Diamond Light Source) and LA-ICP-MS (University of Oxford). The data shows excellent correlation between these two techniques. The diffusion profiles were fitted to a 1-D diffusion couple equation to determine the diffusivities and fitting to the different temperature runs defined the Arrhenius parameters. We find that for 850°C the diffusion coefficients follow the trend Tl>Pb>Cd>Zn>In>Bi>As>Sb>Mo. Additional experiments were performed with either S or Cl added (to both sides of the diffusion couple). In general S increases the diffusion rate of all metals except Mo and Sb, which diffuse slower in the presence of S. Chlorine also speeds up the diffusion of metals with the exception of In, Mo and Sb. The systematic change in diffusivities of these metals and their different behaviour in the presence of the ligands that are also observed to be significant in volcanic gases, are important in determining the distribution of these metals during degassing (e.g. MacKenzie and Canil, 2008). This is particularly important in a dynamic environment such as a volcanic conduit. There are also implications for economic exploration and well as hazard mitigation.

  9. Diffusion-controlled melting in granitic systems at 800-900degC and 100-200 MPa. Temperature and pressure dependence of the minimum diffusivity in granitic melts

    International Nuclear Information System (INIS)

    Yuguchi, Takashi; Yamaguchi, Takashi; Iwamoto, Manji-rou; Eguchi, Hibiki; Isobe, Hiroshi; Nishiyama, Tadao

    2012-01-01

    This paper presents the temperature and pressure dependence of the minimum binary diffusivity in granitic melts. The minimum diffusivities are determined by monitoring the temporal development of the diffusion-controlled melt layer(DCM) in granitic systems (albite (Ab)-quartz (Qtz)-H 2 O and orthoclase (Or)-Qtz-H 2 O) gathered during 31 melting experiments under conditions of 800-900degC and 100-200 MPa for durations of 19-72 h. The DCM is formed between single crystals (Ab or Or crystals) and powdered quartz in all runs and is characterized by a distinct concentration gradient. The maximum thickness of the DCM increases systematically with temperature, pressure, and run duration. Temporal development of the DCM obeys the parabolic growth rate law, using which the diffusivity can be estimated. Plots of concentrations along the diffusion paths in ternary diagrams (Na 2 O-Al 2 O 3 -SiO 2 diagram for the Ab-Qtz-H 2 O system and K 2 O-Al 2 O 3 -SiO 2 diagram for the Or-Qtz-H 2 O system) show linear trends rather than S-shaped trends, indicating that binary nature of diffusion occurs in these systems. Therefore, the diffusive component can be interpreted as an albite component or orthoclase and quartz components (SiO 2 ) rather than an oxide or a cation. (author)

  10. A 7MeV S-Band 2998MHz Variable Pulse Length Linear Accelerator System

    CERN Document Server

    Hernandez, Michael; Mishin, Andrey V; Saverskiy, Aleksandr J; Skowbo, Dave; Smith, Richard

    2005-01-01

    American Science and Engineering High Energy Systems Division (AS&E HESD) has designed and commissioned a variable pulse length 7 MeV electron accelerator system. The system is capable of delivering a 7 MeV electron beam with a pulse length of 10 nS FWHM and a peak current of 1 ampere. The system can also produce electron pulses with lengths of 20, 50, 100, 200, 400 nS and 3 uS FWHM with corresponding lower peak currents. The accelerator system consists of a gridded electron gun, focusing coil, an electrostatic deflector system, Helmholtz coils, a standing wave side coupled S-band linac, a 2.6 MW peak power magnetron, an RF circulator, a fast toroid, vacuum system and a PLC/PC control system. The system has been operated at repetition rates up to 250pps. The design, simulations and experimental results from the accelerator system are presented in this paper.

  11. The TRIUMF 520 MeV cyclotron: recent and future developments

    International Nuclear Information System (INIS)

    Dutto, Gerado.

    1992-08-01

    The TRIUMF cyclotron is now routinely producing 150 μA protons at 500 MeV for meson production with a maximum available current of 200 μA and beam availability of 90%. A successful resonator upgrade program, the recent commissioning of a new 92 MHz rf booster cavity and a new compact CUSP ion source will allow the current to be increased to 225 μA routinely and 300 μA maximum, once an upgrade of the high radiation target areas is completed. Furthermore, the 300 μA maximum H - internal current will allow, in parallel with 100-200 μA for meson production, the simultaneous extraction of 50-100 μA for a radioactive beam facility and of 50-100 μA for isotope production at 70-100 MeV. A proton therapy facility is also proposed. A new optically pumped H - polarized source will allow a highly stable and reproducible 5 μA beam at ∼ 75% polarization to be extracted. The feasibility of the extraction of an H - beam with electrostatic and magnetic channels has also been demonstrated. Problems and plans for the extraction of 150 μA H - for KAON will be discussed. 13 refs., 6 figs

  12. Evidence for two narrow pp resonances at 2020 MeV and 2200 MeV

    CERN Document Server

    Benkheiri, P; Bouquet, B; Briandet, P; D'Almagne, B; Dang-Vu, C; De Rosny, G; Eisenstein, B I; Ferrer, A; Fleury, P; Grossetête, B; Irwin, G; Jacholkowski, A; Lahellec, A; Nguyen, H; Petroff, P; Richard, F; Rivet, P; Roudeau, P; Rougé, A; Rumpf, M; Six, J; Thénard, J M; Treille, D; Volte, A; Yaffe, D; Yiou, T P; Yoshida, H

    1977-01-01

    From the study of the reaction pi /sup -/p to p/sub F/pp pi /sup -/ using a fast proton (p/sub F/) trigger device in the CERN Omega spectrometer, the authors find evidence for two narrow pp states produced mainly in association with a Delta degrees (1232) and a N degrees (1520). The statistical significance of each peak is greater than 6 standard deviations. Masses and natural widths of these resonances are respectively M/sub 1/=2020+or-3 MeV, Gamma /sub 1 /=24+or-12 MeV and M/sub 2/=2204+or-5 MeV, Gamma /sub 2/=16/sub -16 //sup +20/ MeV. The data are consistent with a small production of the narrow approximately 1935 MeV resonance already reported. Production cross sections for these new pp resonances are given. (8 refs).

  13. Positron acceleration to 200 MeV

    International Nuclear Information System (INIS)

    Leboutet, H.

    1983-01-01

    220 MeV is the energy that has to be obtained in routine operation. A standard 12m girder with SLED II can give 220 MeV minus a few percent due to not riding at the crest of the wave. In order to have the 200 MeV with only one girder, a klystron at full power all the time would be required - kept brand new. Then, for safety it is necessary to use two klystrons as designated in the SLC design. Having two klystrons gives freedom for the choice of the best arrangement. Since there will be excess rf power, it can be traded against higher gradient, shorter waveguides, larger apertures (lower shunt impedence)

  14. MeV fullerene impacts on mica

    Energy Technology Data Exchange (ETDEWEB)

    Doebeli, M.; Scandella, L. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Ames, F. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Hillock heights on mica irradiated with MeV C{sub 60} ions have been investigated systematically. Results show that the small range of secondary particles along the track plays a crucial role in defect production. (author) figs., tab., refs.

  15. <600> MeV synchro-cyclotron

    CERN Multimedia

    CERN PhotoLab

    1971-01-01

    One of the 14 pancakes of the new magnet coils for the 600 MeV synchro-cyclotron which were wound and coated with epoxy resin on the CERN site. These new coils will replace the present ones which have been in use for more than 14 years but are now showing signs of deteriorations.

  16. Measurements of pp→π+d between 398 MeV and 572 MeV

    International Nuclear Information System (INIS)

    Aebischer, D.; Favier, B.; Greeniaus, L.G.; Hess, R.; Junod, A.; Lechanoine, C.; Nikles, J.-C.; Rapin, D.; Werren, D.W.

    1976-01-01

    The reaction pp→π + d was studied at incident proton energies of 398, 455, 497, 530 and 572 MeV. Measurements of dsigma/dΩ at 455 and 572 MeV show the presence of pion d-waves in the pion-deuteron system. Asymmetry measurements yield similar conclusions. Total cross-section measurements agree with recent fits to earlier data. (Auth.)

  17. 14 MeV proton activation analysis

    International Nuclear Information System (INIS)

    Constantinescu, B.; Ivanov, E.; Plostinaru, D.; Popa-Nemoiu, A.; Pascovichi, G.

    1985-01-01

    A fast nuclear nondestructive method for protein analysis using the 14 MeV proton activation has been developed. The total nitrogen content was measured through the reaction: 14 N (p,n) 14 O, (Tsub(1/2)=71 s). The 14 O activity was detected by means of its characteristic 2.312 MeV gamma-ray line with a NaI(Tl) detector. For a fast determination of a large number of samples a mechanized sistem reacting a rate of one sample per minute has been developed. The laboratory electronics comprises a multichannel analyser, a PDP computer and an electronic module comtroller. Comparison of the results obtained by the method described and the classical Kjeldal technique for samples of various cereal grains (soya bean seads, wheat, barley and corn) showed good correlation. A problem of the analysis of the whole protein region on corn and soya-bean seads, where this region is thicker (0,2 - 2 mm), is mentioned. In this case flour was proposed to be used to obtain a protein homogeneous sample and the irradiaton dose for a sample was about 33,000 Gy, mainly (99%) from protons (27 s x 100 nA x 14 MeV)

  18. The 200 MeV cyclotron facility

    International Nuclear Information System (INIS)

    1987-01-01

    Beams of protons with several different energies have now been successfully transported between the injector cyclotron SPC1 and the SSC. Some small modifications to the placement of steering magnets and diagnostic equipment have been made in the light of our operational experience, which should improve the ease of tuning this beamline. Proton beams up to 200 MeV in energy have been transported to the experimental areas, where experiments in nuclear physics have been successful conducted. Three of the experimental beamlines are now in operation. Beams of 66 MeV protons have also been transported to targets in the isotope production vault, without difficulty. Field mapping of the remaining quadrupoles on site has been completed. Installation of and alignment of magnets up to the beam swinger is also complete, although the beam tube itself, plus vacuum and diagnostic equipment must still be tackled. The beam swinger has been designed and detailed in the drawing office, and is now being manufactured locally. The beamline elements for the sepctrometer beamline remain to be purchased. A personal computer has been purchased for controlling the field-mapping equipment for the spectrometer magnets, which are being manufactured in this country. A number of computer programs have been written for conversion of calibrated quadrupole and dipole magnet field data to absolute current values for the control system. Other programs permit diagnostic measurements of beam profiles to be used to calculated the beam emittance, or to set steering magnets so that the beam is correctly aligned

  19. HIGH ENERGY RADIOGRAPHY-1-30 Mev

    Energy Technology Data Exchange (ETDEWEB)

    Bly, James H.

    1963-10-15

    From 1963 American Society of Metals/Materials Show, Cleveland, Oct. 1963. A survey of the field of radiographic inspection of thick sections, at one million volts energy or more, shows that this field has become a major branch of radiographic testing. More than a dozen models of x-ray generators are now commercially available in this field, over the range from 1 to 31 Mev, with outputs up to more than two orders of magnitude greater than can be obtained from radiographic isotope sources, and with smaller spot size. A study of the radiographic characteristics of x rays in this region shows that energies available cover the range of minimum absorption and scattering for most materials and approach this range for solid propellant; at higher energies severe coverage restrictions are imposed; output powers on small spots are near the limits of present target technology. It would appear that some degree of technological maturity'' has been achieved. Radiographic technique at 1 to 30 Mev is straightforward, following the same basic principles as in conventional radiography. Specialized aspects of technique are individually discussed. The wellknown 1 and 2 million volt equlpments are supplemented by a wide variety of higher-energy machines, with energy and output ratings to satisfy almost any radiographic need. Some examples are epitomized, and a brief discussion of possible future developments is presented. (auth)

  20. Study of the /sup 12/N 2. 43 MeV level. [Differential cross sections; 44 MeV /sup 3/He; 52 MeV p

    Energy Technology Data Exchange (ETDEWEB)

    Cecil, F E; Shepard, J R; Sercely, R R; Peterson, R J [Colorado Univ., Boulder (USA). Nuclear Physics Lab.; King, N S.P. [California Univ., Davis (USA). Crocker Nuclear Lab.

    1976-10-11

    The differential cross sections have been measured for the reactions /sup 12/C(/sup 3/He, /sup 3/He')/sup 12/C(17.77 MeV 0/sup +/ T = 1) and /sup 12/C(/sup 3/He, t)/sup 12/N(2.43 MeV) at Esub(/sup 3/He) = 44 MeV. The similar shapes of the angular distributions and the relative magnitudes of the cross sections suggest that the /sup 12/N 2.43 MeV level is the 0/sup +/ T = 1 analog to the /sup 12/C 17.77 MeV level. The reaction /sup 14/N(p, t)/sup 12/N(2.43 MeV) at Esub(p) = 52 MeV is also studied. The strength with which this level is excited in this reaction is consistent with reasonable two-step calculations assuming the 2.43 MeV level to have Jsup(..pi..) = 0/sup +/.

  1. Characterization of 2 MeV, 4 MeV, 6 MeV and 18 MeV buildup caps for use with a 0.6 cubic centimeter thimble ionization chamber

    International Nuclear Information System (INIS)

    Salyer, R.L.; VanDenburg, J.W.; Prinja, A.K.; Kirby, T.; Busch, R.; Hong-Nian Jow

    1996-07-01

    The purpose of this research is to characterize existing 2 MeV, 4 MeV and 6 MeV buildup caps, and to determine if a buildup cap can be made for the 0.6 cm 3 thimble ionization chamber that will accurately measure exposures in a high-energy photon radiation field. Two different radiation transport codes were used to computationally characterize existing 2 MeV, 4 MeV, and 6 MeV buildup caps for a 0.6 cm 3 active volume thimble ionization chamber: ITS, The Integrated TIGER Series of Coupled Electron-Photon Monte Carlo Transport Codes; and CEPXS/ONEDANT, A One-Dimensional Coupled Electron-Photon Discrete Ordinates Code Package. These codes were also used to determine the design characteristics of a buildup cap for use in the 18 MeV photon beam produced by the 14 TW pulsed power HERMES-III electron accelerator. The maximum range of the secondary electron, the depth at which maximum dose occurs, and the point where dose and collision kerma are equal have been determined to establish the validity of electronic equilibrium. The ionization chamber with the appropriate buildup cap was then subjected to a 4 MeV and a 6 MeV bremmstrahlung radiation spectrum to determine the detector response

  2. 14 MeV neutrons physics and applications

    CERN Document Server

    Valkovic, Vladivoj

    2015-01-01

    Despite the often difficult and time-consuming effort of performing experiments with fast (14 MeV) neutrons, these neutrons can offer special insight into nucleus and other materials because of the absence of charge. 14 MeV Neutrons: Physics and Applications explores fast neutrons in basic science and applications to problems in medicine, the environment, and security.Drawing on his more than 50 years of experience working with 14 MeV neutrons, the author focuses on:Sources of 14 MeV neutrons, including laboratory size accelerators, small and sealed tube generators, well logging sealed tube ac

  3. Review of neutron data: 10 to 40 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Haight, R.C.

    1977-04-01

    Neutron data are reviewed for incident neutron energies between 10 and 40 MeV. A census of the data shows that there are many gaps in this range and that the existing data are primarily for neutron energies around 14 MeV. Aside from total cross sections, there are few data between 10 and 13 MeV and between 15 and 40 MeV. Examples are presented to show the quality of selected data for total, elastic, inelastic, activation, and charged-particle and gamma-ray production cross sections. The spectra of emitted particles are also discussed.

  4. Review of neutron data: 10 to 40 MeV

    International Nuclear Information System (INIS)

    Haight, R.C.

    1977-04-01

    Neutron data are reviewed for incident neutron energies between 10 and 40 MeV. A census of the data shows that there are many gaps in this range and that the existing data are primarily for neutron energies around 14 MeV. Aside from total cross sections, there are few data between 10 and 13 MeV and between 15 and 40 MeV. Examples are presented to show the quality of selected data for total, elastic, inelastic, activation, and charged-particle and gamma-ray production cross sections. The spectra of emitted particles are also discussed

  5. Coherent pion production induced by 300 MeV and 600 MeV deuterons

    International Nuclear Information System (INIS)

    Aslanides, E.; Bergdolt, A.M.; Bing, O.; Fassnacht, P.; Hibou, F.

    1982-01-01

    Experimental data on (d,π - ) reactions at 300 and 600 MeV incident energy are presented. Inclusive spectra on 6 Li, 9 Be and 10 B targets near the kinematical limit do not show the usual scaling behaviour. For the two-body reaction 6 Li (d,π - ) 8 B the lowest-energy discrete states of the final nucleus were clearly resolved and the cross sections for pion production leading to those states have been determined. (orig.)

  6. NSRL 200 MeV linac beam energy stabilization system

    International Nuclear Information System (INIS)

    Huang Guirong; Pei Yuanji; Dong Sai

    2001-01-01

    By using the computer image processing technology and RF phase auto-shifting system, the ESS (Energy Stabilization System) was applied to 200 MeV Linac. the ESS adjusts beam energy automatically in a range of +-4 MeV. After adjustment beam energy stability is improved to +-6%

  7. Scattering of 130 MeV helions on 58Ni

    International Nuclear Information System (INIS)

    Djaloeis, A.; Alderliesten, C.; Bojowald, J.; Oelert, W.; Turek, P.

    1982-01-01

    Angular distributions for the tau + 58 Ni scattering to the (g.s., 0 + ) (1.45 MeV, 2 + ) and giant resonance (Esub(x) approximately 63Asup(-1/3) MeV) states in 58 Ni have been measured at Esub(tau) = 130 MeV in an angular range thetasub(c.m.) = 6 0 -83 0 . Optical model and DWBA analyses have been performed. The use of helion optical potentials with either a volume (Woods-Saxon) or a surface (Woods-Saxon derivative) absorption results in good fits to the g.s. and 1.45 MeV data. However, the volume absorption gives consistently a better fit quality. The discrete ambiguity of the helion optical potential has been resolved in favour of the shallow potential family. The giant resonance is found to have a dominant quadrupole (L=2) character with about 6% (EWSR) L=4 admixture. (Auth.)

  8. Performances of large BGO crystals below 20 MeV

    International Nuclear Information System (INIS)

    Burq, J.P.; Chemarin, M.; El Mamouni, H.

    1986-11-01

    This paper presents the performances of large tapered BGO crystals to low energy photons of 6 to 20 MeV. The read-out of the crystals was made with large area photodiodes associated to shaping amplifiers

  9. Studies of yrast and continuum states in A = 100--200 nuclei

    International Nuclear Information System (INIS)

    Daly, P.J.

    1992-02-01

    This report summarizes progress in nuclear structure research for the year 1991. The highlights include new spectroscopic results for neutron excessive nuclei (around 124 Sn and 36 S) formed in deep inelastic heavy ion reactions

  10. Quarterly Environmental Radiological Survey Summary Third Quarter 1998, 100, 200, 300, and 600 Areas; TOPICAL

    International Nuclear Information System (INIS)

    MCKINNEY, S.M.

    1998-01-01

    This report provides a summary of the radiological surveys performed in support of near-facility environmental monitoring at the Hanford Site. The Third Quarter 1998 survey results and the status of actions required are summarized: (1) All of the eighty-five environmental radiological surveys scheduled during July, August and September were performed as planned. Fifty-one of the surveys were conducted at Project Hanford Management Contractors (PHMC) sites and thirty-four at Environmental Restoration Contractor (ERC) sites. Contamination above background levels was found at seventeen of the PHMC waste sites and two of the ERC waste sites. Contamination levels as high and gt;1,000,000 disintegrations per minute (dpm) per 100 cm(sup 2) were reported. Of these contaminated surveys nine were in Underground Radioactive Material (URM) areas, three were in unposted areas and seven were in contamination areas. The contamination found within four of the URM and three of the CA areas was immediately cleaned up and no further action was required. The remaining five URM and two unposted sites were posted and along with the five CA sites will require remediation. Radiological Problem Reports (RPR's) were issued and the sites were turned over to the landlord for further action as required. (2) During the second quarter of 1998, 1.2 hectares (3.0 acres) were stabilized and radiologically down posted from Contamination Area (CA)/Soil Contamination (SC) to URM. (3) Four hectares (10 acres) located south and west of B-Plant were posted as a radiological buffer area as a result of a contamination spread. This off-normal occurrence is currently being investigated. (4) Four Surveillance Compliance Inspection Reports (SCIRs) remained open and had not been resolved. Tank Farms Operations has responsibility for the unresolved SCIRs

  11. Quarterly environmental radiological survey summary: First quarter 1995 100, 200, 300, and 600 Areas

    International Nuclear Information System (INIS)

    McKinney, S.M.

    1995-04-01

    This report provides a summary of the radiological surveys performed in support of the operational environmental monitoring program at the Hanford Site. The surveys included in this program consist of inactive waste sites; outdoor radiological control areas; tank farm perimeters and associated diversion boxes, lift stations, and vent stations; perimeters of active or uncovered waste sites such as burial grounds, retention basins, ponds, process trenches, and ditches; and road and rail surfaces. This report provides a summary of the radiological surveys performed during the First Quarter of 1995. The status of corrective actions required from current and past reports are also discussed

  12. Quarterly environmental radiological survey summary: Second Quarter 1995 100, 200, 300, and 600 Areas

    International Nuclear Information System (INIS)

    McKinney, S.M.

    1995-01-01

    This report provides a summary of the radiological surveys performed in support of the operational environmental monitoring program at the Hanford Site. The Second Quarter 1995 survey results and the status of actions required from current and past reports are summarized

  13. Quarterly environmental radiological survey summary: 100, 200, 300 and 600 Areas. Fourth quarter 1994

    International Nuclear Information System (INIS)

    McKinney, S.M.

    1995-01-01

    This report provides a summary of the radiological surveys performed on waste disposal sites located at the Hanford Site. The Fourth Quarter 1994 survey results and the status of actions required from current and past reports are summarized

  14. Quarterly environmental radiological survey summary: Third quarter 1994--100, 200, 300, and 600 Areas

    International Nuclear Information System (INIS)

    McKinney, S.M.

    1994-11-01

    This report provides a summary of the radiological surveys performed on waste disposal sites located at the Hanford Site. The Third Quarter 1994 survey results and the status of actions required from current and past reports and are summarized below: (1) All the routine environmental radiological surveys scheduled during July, August, and September 1994 were completed except for the D Island vent riser area. The surveys for the 200-W railways, spurs, and sidings were completed during this period after being delayed by equipment problems during the second quarter. (2) No Compliance Assessment Reports (CARs) were issued for sites found out of compliance with standards identified in WHC-CM-7-5, Environmental Compliance. (3) Two Surveillance Compliance/Inspection Reports (SCIRs) were closed during the Third Quarter of 1994. (4) Eleven open SCIRs had not been resolved

  15. Quarterly environmental radiological survey summary - second quarter 1997 100, 200, 300, and 600 areas

    International Nuclear Information System (INIS)

    McKinney, S.M.; Marks, B.M.

    1997-01-01

    This report provides a summary of the radiological surveys performed in support of near-facility environmental monitoring at the Hanford Site. The Second Quarter 1997 survey results and the status of actions required are summarized below: All of the routine environmental radiological surveys scheduled during April, May, and June 1997, were performed as planned with the exception of UN-216-E-9. This site was not surveyed as stabilization activities were in progress. The sites scheduled for the Environmental Restorations Contractor (ERC) team were switched with those identified for the third quarter as there was a conflict with vegetation management activities

  16. Quarterly environmental radiological survey summary - first quarter 1997 100, 200, 300, and 600 areas

    International Nuclear Information System (INIS)

    Mckinney, S.M.

    1997-01-01

    This report provides a summary of the radiological surveys performed in support of near-facility environmental monitoring at the Hanford Site. The First Quarter 1997 survey results and the status of actions required are summarized below: (1) All of the routine environmental radiological surveys scheduled during January, February, and March 1997, were performed as planned. (2) One hundred four environmental radiological surveys were performed during the first quarter 1997, twenty-nine at the active waste sites and seventy-five at the inactive waste sites. Contamination above background levels was found at eight of the active waste sites and seven of the inactive waste sites. Contamination levels as high as >1,000,000 disintegrations per minute (dpm) were reported. Of these contaminated surveys twelve were in Underground Radioactive Material (URM) areas and three were in contamination areas. The contamination found within ten of the URM areas was immediately cleaned up and no further action was required. In the remaining five sites the areas were posted and will require decontamination. Radiological Problem Reports (RPR's) were issued and the sites were turned over to the landlord for further action if required. (3) During the first quarter of 1997, 5.6 hectares (13.8 acres) were stabilized and radiologically down posted from Contamination Area (CA)/Soil Contamination (SC) to URM. (4) During the first quarter of 1997, the size of 216-A-25 Gable Mountain Pond was increased from 30.4 to 34.5 hectares (75.0 to 85.2 acres). This increase in size was due to the correction of the original boundary area by using the advanced technology of a global positioning system (GPS). An area, 1.6 hectares (4.0 acres), east of and adjacent to the 241-S/SX/SY tank farm complex was posted as a contamination/soil contamination area. (5) Five open Surveillance Compliance Inspection Reports (SCIRs) had not been resolved

  17. Quarterly environmental radiological survey summary. Fourth quarter, 1995 100, 200, 300, and 600 Areas

    International Nuclear Information System (INIS)

    McKinney, S.M.; Markes, B.M.

    1996-01-01

    This report provides a summary of the radiological surveys performed in support of the operational environmental monitoring program at the Hanford Site. The Fourth Quarter 1995 survey results and the status of actions required from current and past reports are described

  18. The reaction p12C→ηX from Tp=800 MeV to Tp=1500 MeV

    International Nuclear Information System (INIS)

    Chiavassa, E.; Dellacasa, G.; De Marco, N.; De Oliveira Martins, O.; Gallio, M.; Guaita, P.; Musso, A.; Piccotti, A.; Scomparin, E.; Vercellin, E.

    1998-01-01

    The reaction p 12 C→nX has been studied, at several proton kinetic energies ranging from 800 MeV to 1500 MeV, at the proton synchrotron Saturne at Saclay. The measured doubly differential cross-sections are presented and discussed in the framework of a simple theoretical model. The model fails in describing the deepest subthreshold data while the above-threshold data are fairly well reproduced. (orig.)

  19. MeV Mott polarimetry at Jefferson Lab

    International Nuclear Information System (INIS)

    Steigerwald, M.

    2001-01-01

    In the recent past, Mott polarimetry has been employed only at low electron beam energies (≅100 keV). Shortly after J. Sromicki demonstrated the first Mott scattering experiment on lead foils at 14 MeV (MAMI, 1994), a high energy Mott scattering polarimeter was developed at Thomas Jefferson National Accelerator Facility (5 MeV, 1995). An instrumental precision of 0.5% was achieved due to dramatic improvement in eliminating the background signal by means of collimation, shielding, time of flight and coincidence methods. Measurements for gold targets between 0.05 μm and 5 μm for electron energies between 2 and 8 MeV are presented. A model was developed to explain the depolarization effects in the target foils due to double scattering. The instrumental helicity correlated asymmetries were measured to smaller than 0.1%

  20. A 30 MeV H- cyclotron for isotope production

    International Nuclear Information System (INIS)

    Baartman, R.; Kleevan, W.J.; Laxdal, R.E.; Milton, B.F.; Otter, A.J.; Pearson, J.B.; Poirier, R.L.; Schmor, P.W.; Schneider, H.R.; Erdman, K.L.; Walker, Q.

    1989-01-01

    Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. We describe such a cyclotron currently under construction. It is a 30 MeV H - design that exploits a newly developed high brightness multicusp ion source which is capable of H - currents of up to 5 mA. This together with careful beam matching then makes feasible accelerated H - beam intensities of 500 μA. The cyclotron being built is a four sector radial ridge design with two 45 degree dees in opposite valleys. Beam extraction is by stripping to H + in a thin graphite foil. Two extraction probes will allow simultaneous extraction of two beams, each with an intensity of up to 200 μA. Energy variation from 15 MeV to 30 MeV is achieved by varying the radial position of the extraction foil. 7 refs., 4 figs., 1 tab

  1. Investigation of transversal nuclear excitation in 208Pb at excitation energies between 6 MeV and 8 MeV using inelastic electron scattering

    International Nuclear Information System (INIS)

    Frey, R.W.

    1978-01-01

    Using high resolution inelastic electron scattering magnitic dipole and quadrupole excitations in 208 Pb were investigated in the energy range between 6 MeV and 8 MeV. The electron energy was 50 MeV and 63.5 MeV. With a mean absolute energy resolution of 33 kev. 44 excited states were found in the above energy range. The measured angular distributions were compared with DWBA-calculations using random phase approximated wave functions. (FKS)

  2. Conversion efficiency of lead for 30-200 MeV photons

    International Nuclear Information System (INIS)

    Darriulat, P.; Gygi, E.; Holder, M.; McDonald, K.T.; Pugh, H.G.; Schneider, F.; Tittel, K.

    1975-01-01

    The conversion efficiency of lead has been measured as a function of thickness for 44 MeV, 94 MeV and 177 MeV photons, and as a function of energy between 29 MeV and 177 Mev for thickness of one and two radiation lengths. Some additional information on multiplicity of secondary tracks and on their angular distribution was obtained using a small streamer chamber. The results obtained confirm the shower calculations of Messel and Crawford. (Auth.)

  3. The JHP 200-MeV proton linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Takao [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

    1997-11-01

    A 200-MeV proton linear accelerator for the Japanese Hadron Project (JHP) has been designed. It consists of a 3-MeV radio-frequency quadrupole linac (RFQ), a 50-MeV drift tube linac (DTL) and a 200-MeV separated-type drift tube linac (SDTL). A frequency of 324 MHz has been chosen for all of the rf structures. A peak current of 30 mA (H{sup -} ions) of 400 {mu}sec pulse duration will be accelerated at a repetition rate of 25 Hz. A future upgrade plan up to 400 MeV is also presented, in which annular-coupled structures (ACS) of 972 MHz are used in an energy range of above 150 or 200 MeV. One of the design features is its high performance for a beam-loss problem during acceleration. It can be achieved by separating the transition point in the transverse motion from that of the longitudinal motion. The transverse transition at a rather low-energy range decreases the effects of space-charge, while the longitudinal transition at a rather high-energy range decreases the effects of nonlinear problems related to acceleration in the ACS. Coupled envelope equations and equipartitioning theory are used for the focusing design. The adoption of the SDTL structure improves both the effective shunt impedance and difficulties in fabricating drift tubes with focusing magnets. An accurate beam-simulation code on a parallel supercomputer was used for confirming any beam-loss problem during acceleration. (author)

  4. Production of radionuclides by 14 MeV neutron generator

    International Nuclear Information System (INIS)

    Alfassi, Z.B.

    1983-01-01

    Due to the short half-lives of these nuclides they have to be produced in situ or at least not far from the place of use. The cost of 14 MeV neutron generators have been compared with the typical middle-sized cyclotrons and it was found that the capital costs are much lower in the case of neutron generators. This is the main reason for the availability of 14 MeV neutron generators in many scientific institutes compared to the scarcity of cyclotrons. Lately, the use of 14 MeV neutrons for cancer therapy was studied in several medical centers. A number of hospitals and cancer research centers have high intensity 14 MeV neutron generators for this purpose. The advantages of using short-lived in-house produced radionuclides suggest the use of the available 14 MeV neutron generators for biological studies and in medical diagnosis. 14 MeV neutron generators can be used to produce some of the medically useful radionuclides, such as /sup 18/F, /sup 80/Br, /sup 199m/Hg, and others. However, the amount required for medicine can only be prepared by the new high intensity neutron generators, used for neutron therapy and not by the smaller ones, commonly used in university laboratories (--10/sup 11/ n/sec). On the other hand, these relatively small neutron generators can be used for the preparation of radionuclides for biological studies. They facilitate the study of metabolism of elements for which radionuclides cannot be usually purchased due to short half-lives or the high price of the long-lived ones, such as /sup 34m/Cl, /sup 18/F, /sup 28,29/Al, /sup 27/Mg, and others. An example is the work done on the fate of Al and Mg in rats using /sup 28/Al and /sup 27/Mg./sup 13/

  5. Crosslinking of commercial polyethylenes by 10 MeV electrons

    International Nuclear Information System (INIS)

    Singh, A.; Lopata, V.J.; Kremers, W.; Sze, Yu-keung

    1995-08-01

    Commercial polyethylenes were irradiated with 10 MeV electrons to induce crosslinking. The gel fraction data measured as a function of total dose suggests that crosslinking proceeds on irradiation, as expected. A number of the properties of the irradiated polyethylenes, such as the degree of oxidation, crystallinity and thermal degradation, were studied by Fourier transform infrared/photo acoustic spectroscopy, X-ray diffraction, and a pyrolysis technique coupled with gas chromatography and mass spectrometry. The results of this study suggest that commercial polyethylenes can be crosslinked to a gel fraction of ∼70%, required for wire and cable applications, by 10 MeV electrons. (author). 35 refs., 6 figs

  6. A P + DEUTERON PROTON POLARIMETER AT 200 MEV.

    Energy Technology Data Exchange (ETDEWEB)

    HUANG,H.; ROSER,T.; ZELENSKI,A.; KURITA,K.; STEPHENSON,E.; TOOLE,R.

    2002-06-02

    There has been concern about the analyzing power of the p-Carbon polarimeter at the end of 200 MeV LINAC of BNL. A new polarimeter based on proton-deuteron scattering was installed and we have repeated the calibration of proton-Carbon scattering at 12 degrees and 200 MeV against proton-deuteron scattering. The result is consistent with the value of A=0.62 now used to measure the beam polarization at the end of the LINAC.

  7. Charge measurement system at 100 MeV linac

    International Nuclear Information System (INIS)

    Li Dongmei; Chinese Academy of Sciences, Beijing; Yin Chongxian; Ye Kairong

    2005-01-01

    A charge measurement system of 100 Mev linac is introduced in this paper. After describing the characteristics and functions of the system's components, the authors analyze the methods of data processing and systematic error in detail. Basing on these, the authors get system resolution in the lab. The actual measurement results are presented at last. (authors)

  8. 3 MeV DC accelerator, EBC Kharghar

    International Nuclear Information System (INIS)

    Bakhtsingh, R.I.; Acharya, S.

    2017-01-01

    The Accelerator and Pulse Power Division (APPD) has designed and developed a 3 MeV, 10 mA DC electron beam accelerator at Electron Beam Centre, Kharghar, Navi Mumbai. This machine has been utilized for reduction of SO_x and NO_x in simulated flue gases and treatment of waste water to reduce COD and BOD

  9. Linac4 crosses the 100 MeV threshold

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    The new linear accelerator, which from 2020 will be the first link in the accelerator chain, has entered a new stage of its commissioning.   Members of the team in charge of the commissioning of Linac4 in the accelerator’s control room. A few hours earlier, Linac4 accelerated a beam to 107 MeV for the first time. We couldn’t have imagined a more appropriate date: on 1 July (1.07), Linac4 reached an energy of 107 MeV. Having crossed the 100 MeV barrier, the linear accelerator is now on the home straight of its commissioning. “This stage was very quick – it took less than two weeks,” says Alessandra Lombardi, deputy project leader of Linac4, in charge of the commissioning. In 2020, Linac4 will replace the existing Linac2 as the first link in the accelerator chain. It will accelerate beams of H- ions (protons surrounded by two electrons) to 160 MeV, compared to 50 MeV with Linac2. The new machine is particularly sophisticated as it comprises...

  10. A 30 MeV H- cyclotron for isotope production

    International Nuclear Information System (INIS)

    Milton, B.F.; Dawson, R.; Erdman, K.L.

    1989-05-01

    Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. TRIUMF is cooperating with a local industrial company in designing and constructing such a cyclotron. It will be a four sector H - cyclotron, exploiting the newly developed high brightness multicusp ion source. This source with H - current capability in excess of 5 mA makes feasible accelerated H - beam intensities of up to 500 μA. Beam extraction is by stripping to H + in a thin graphite foil. Extraction of two high-intensity beams, with energy variable from 15 to 30 MeV is planned. The use of an external ion source, provision of a good vacuum in the acceleration region, and the careful choice of materials for components in the median plane leads to a cyclotron that will have low activation and can be easily serviced in spite of the very high operating beam intensities. A design extension to 70 MeV using many of the design features of the 30 MeV cyclotron can be easily made. Such a machine with a good quality variable energy beam is a highly desirable source of protons for isotope production, injection into higher energy high intensity acceleration, injection into higher energy high intensity accelerators, and as an irradiation facility for ocular melanomas. Design of the 30 MeV cyclotron is well advanced and construction is in progress

  11. MEV Energy Electrostatic Accelerator Ion Beam Emittance Measurement

    OpenAIRE

    I.G. Ignat’ev; M.I. Zakharets; S.V. Kolinko; D.P. Shulha

    2014-01-01

    The testing equipment was designed, manufactured and tried out permitting measurements of total current, current profile and emittance of an ion beam extracted from the ion beam. MeV energy electrostatic accelerator ion H + beam emittance measurement results are presented.

  12. (n, Xn) cross sections measurements at 96 MeV

    International Nuclear Information System (INIS)

    Sagrado Garcia, Inmaculada C.

    2006-01-01

    Nucleon induced reactions in the 20-200 MeV energy range are intensively studied since a long time. The evaporation and the pre-equilibrium processes correspond to an important contribution of the production cross section in these reactions. Several theoretical approaches have been proposed and their predictions must be tested. The experimental results shown in this work are the only complete set of data for the (n, Xn) reactions in this energy range. Neutron double differential cross sections measurements using lead and iron targets for an incident neutron beam at 96 MeV were carried out at TSL laboratory, in Uppsala (Sweden). The measurements have been performed for the first time with an energy threshold of 2 MeV and for a wide angular range (15 deg.-98 deg.). Neutrons have been detected using two independent setups, DECOI and DEMON and CLODIA and SCANDAL, in order to cover the whole energy range (2-100 MeV). The angular distributions, the differential cross sections and the total inelastic production cross sections have been calculated using the double differential cross sections. The comparisons between the experimental data and the predictions given by two of the most popular simulation codes, GEANT3 and MCNPX, have been performed, as well as the comparison with the predictions of the microscopic simulation model DYWAN, selected for its original treatment of nucleon-nucleus reactions. (author) [fr

  13. Alpha-deuteron elastic scattering around 40 MeV

    International Nuclear Information System (INIS)

    De, A.; Karmakar, S.; Roychaudhury, T.; Dasgupta, S.S.; Chintalapudi, S.N.; Ismail, M.; Banerjee, S.R.; Divatia, A.S.

    1989-01-01

    Differential cross section for alpha-deuteron elastic scattering has been measured at several energies around 40 MeV incident alpha. General behaviour of angular distributions remaining close to that predicted by Faddeev type calculations, a sharp energy dependence is observed. (author). 8 refs

  14. History of the ZGS 500 MeV booster.

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.; Martin; R.; Kustom, R.

    2006-05-09

    The history of the design and construction of the Argonne 500 MeV booster proton synchrotron from 1969 to 1982 is described. This accelerator has since been in steady use for the past 25 years to power the Argonne Intense Pulsed Neutron Source (IPNS).

  15. 200 MeV RF linac for synchrotron injection

    International Nuclear Information System (INIS)

    Whitham, K.; Anamkath, H.; Lyons, S.; Manca, J.; Miller, R.; Treas, P.; Zante, T.; Miller, R.

    1992-01-01

    Construction has been completed on an electron linear accelerator for the Brookhaven National Laboratory. This accelerator will be used for the injection of a 200 MeV electron beam into a synchrotron for lithography experiments. This paper describes the conceptual design of the linac, its e-gun pulser, and its control and timing systems. 3 figs., ref

  16. Escaping 1 MeV tritons in TFTR

    International Nuclear Information System (INIS)

    Zweben, S.J.; Strachan, J.D.; Boivin, R.; Cavallo, A.; Fredrickson, E.D.; McGuire, K.; Mynick, H.E.; White, R.B.

    1989-01-01

    1 MeV tritons created by D-D reactions can simulate the 'single-particle' behavior expected with 3.5 MeV D-T alphas, since the gyroradii and slowing-down of these two particles are similar. This paper describes measurements of the flux of escaping 1 MeV tritons from the TFTR plasma during high power D 0 →D neutral beam injection, and shows that in most cases the observed triton loss is consistent with the classical (single-particle) first-orbit loss model. In this model tritons are lost if their first orbit intersects the wall due to their large banana width, while almost all tritons confined on their first orbit should stay confined until thermalized. The triton detectors are ZnS(Ag) scintillator screens housed in light-tight boxes located just outside the plasma boundary at the bottom of the TFTR vessel. They are particle 'pinhole' cameras which can resolve the triton flux vs. pitch angle (to ±5 o ), energy (to ±50 %), and time (to <20 μsec). The 2-D images of triton flux onto these scintillators are optically coupled to either an intensified TV camera or to photomultiplyer tubes for fast time resolution. The soft x-ray background in an earlier prototype has been eliminated. Although there are presently 8 such detectors in TFTR, this paper discusses results from only the detector located just below the vessel center (R=259 cm, r=102 cm). Note that the '1 MeV triton' signal discussed below also has about a 30 % contribution from 3 MeV protons; however, since these two particles have identical gyroradii they should behave alike. 5 refs., 5 figs

  17. The Fermilab 400-MeV Linac Upgrade

    International Nuclear Information System (INIS)

    Schmidt, C.W.

    1993-05-01

    The Fermilab Linac Upgrade will increase the linac energy from 201 MeV to 401.5 MeV. Seven accelerating modules, composed of 805-MHz side-coupled cells, will accelerate H - beams from 116.5 to 401.5 MeV. The side-coupled structure (SCS) has been built, tuned, tested to full power, and placed in the linac enclosure along side the operating Linac. All seven accelerating modules, each containing four sections of sixteen cells, have been connected to 12-MW power klystrons and tested to full power for a significant period. The transition section to match the beam from the 201.25-MHz drift-tube linac to the SCS, consisting of a sixteen-cell cavity and a vernier four-cell cavity, has also been tested at full power. A new import line from the Linac to the Booster synchrotron with a new Booster injection girder is to be installed. Removal of the last four Alvarez linac tanks (116.5 to 201 MeV) and beam-line installation of the Upgrade components is to begin in early June 1993 and should take about 12 weeks. Beam commissioning of the project will follow and normal operation is expected in a short period. In preparation for beam commissioning, studies are being done with done operating linac to characterize the beam at transition and prepare for phase, amplitude and energy measurements to commission the new linac. The past, present and future activities of the 400-MeV Upgrade will be reviewed

  18. Measured neutron carbon kerma factors from 14.1 MeV to 18 MeV

    International Nuclear Information System (INIS)

    Deluca, P.M.; Barschall, H.H.; McDonald, J.C.

    1985-01-01

    For A-150 tissue-equivalent plastic, the total neutron kerma is dominated by the hydrogen kerma. Tissue kerma is inferred with reasonable accuracy by normalization to the kerma factor ratio between tissue and A-150 plastic. Because of the close match in the hydrogen abundance in these materials, the principal uncertainty is due to the kerma factors of carbon and oxygen. We have measured carbon kerma factor values of 0.183+-0.015 10 -8 cGy cm 2 and 0.210+-0.016 10 -8 cGy cm 2 at 14.1-MeV and 15-MeV neutron energy, respectively. A preliminary value of 0.297+-0.03 10 -8 cGy cm 2 has been determined at 17.9 MeV. A recent microscopic cross section measurement of the (n,n'3α) reaction in carbon at 14.1-MeV energy gives a kerma factor of 0.184+-0.019 10 -8 cGy cm 2 in agreement with the present result

  19. Measured neutron carbon kerma factors from 14.1 MeV to 18 MeV

    International Nuclear Information System (INIS)

    Deluca, P.M. Jr.; Barschall, H.H.; Haight, R.C.; McDonald, J.C.

    1984-01-01

    For A-150 tissue-equivalent plastic, the total neutron kerma is dominated by the hydrogen kerma. Tissue kerma is inferred with reasonable accuracy by normalization to the kerma factor ratio between tissue and A-150 plastic. Because of the close match in the hydrogen abundance in these materials, the principal uncertainty is due to the kerma factors of carbon and oxygen. We have measured carbon kerma factor values of 0.183 +- 0.015 10 -8 cGy cm 2 and 0.210 +- 0.16 10 -8 cGy cm 2 at 14.1-MeV and 15-MeV neutron energy, respectively. A preliminary value of 0.297 +- 0.03 10 -8 cGy cm 2 has been determined at 17.9 MeV. A recent microscopic cross section measurement of the (n,n'3α) reaction in carbon at 14.1-MeV energy gives a kerma factor of 0.184 +- 0.019 10 8 cGy cm 2 in agreement with the present result. 9 refs., 4 figs., 2 tabs

  20. Comparison of biological and genomic characteristics between a newly isolated mink enteritis parvovirus MEV-LHV and an attenuated strain MEV-L.

    Science.gov (United States)

    Mao, Yaping; Wang, Jigui; Hou, Qiang; Xi, Ji; Zhang, Xiaomei; Bian, Dawei; Yu, Yongle; Wang, Xi; Liu, Weiquan

    2016-06-01

    A virus isolated from mink showing clinical signs of enteritis was identified as a high virulent mink enteritis parvovirus (MEV) based on its biological characteristics in vivo and in vitro. Mink, challenged with this strain named MEV-LHV, exhibited severe pathological lesions as compared to those challenged with attenuated strain MEV-L. MEV-LHV also showed higher infection and replication efficiencies in vitro than MEV-L. Sequence of the complete genome of MEV-LHV was determined and analyzed in comparison with those in GenBank, which revealed that MEV-LHV shared high homology with virulent strain MEV SD12/01, whereas MEV-L was closely related to Abashiri and vaccine strain MEVB, and belonged to a different branch of the phylogenetic tree. The genomes of the two strains differed by insertions and deletions in their palindromic termini and specific unique mutations (especially VP2 300) in coding sequences which may be involved in viral replication and pathogenicity. The results of this study provide a better understanding of the biological and genomic characteristics of MEV and identify certain regions and sites that may be involved in viral replication and pathogenicity.

  1. Magnifying lens for 800 MeV proton radiography

    International Nuclear Information System (INIS)

    Merrill, F. E.; Campos, E.; Espinoza, C.; Hogan, G.; Hollander, B.; Lopez, J.; Mariam, F. G.; Morley, D.; Morris, C. L.; Murray, M.; Saunders, A.; Schwartz, C.; Thompson, T. N.

    2011-01-01

    This article describes the design and performance of a magnifying magnetic-lens system designed, built, and commissioned at the Los Alamos National Laboratory (LANL) for 800 MeV flash proton radiography. The technique of flash proton radiography has been developed at LANL to study material properties under dynamic loading conditions through the analysis of time sequences of proton radiographs. The requirements of this growing experimental program have resulted in the need for improvements in spatial radiographic resolution. To meet these needs, a new magnetic lens system, consisting of four permanent magnet quadrupoles, has been developed. This new lens system was designed to reduce the second order chromatic aberrations, the dominant source of image blur in 800 MeV proton radiography, as well as magnifying the image to reduce the blur contribution from the detector and camera systems. The recently commissioned lens system performed as designed, providing nearly a factor of three improvement in radiographic resolution.

  2. XRD study of yttria stabilized zirconia irradiated with 7.3 MeV Fe, 10 MeV I, 16 MeV Au, 200 MeV Xe and 2.2 GeV Au ions

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, K.; Yoshizaki, H. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Saitoh, Y. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Ishikawa, N. [Tokai Research and Development Center, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Iwase, A., E-mail: iwase@mtr.osakafu-u.ac.jp [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan)

    2016-03-01

    To simulate energetic neutron irradiation effects, yttria-stabilized zirconia (YSZ) which is one of the major materials for electrical corrosion potential sensors (ECP sensors) was irradiated with heavy ions at energies ranging from 7.3 MeV to 2.2 GeV. Ion irradiation effects on the lattice structure were analyzed using the X-ray diffraction (XRD). The increase in lattice constant was induced by the ion irradiation. It was dominated by the elastic collision process and not by the electronic excitation process. The lattice disordering which was observed as a broadening of XRD peaks was also induced by the irradiation especially for 200 MeV Xe ion irradiation. The present result suggests that the expansion and/or the disordering of YSZ lattice induced by energetic neutrons may affect the durability of a joint interface between a metal housing and YSZ membrane for the usage of ECP sensors in nuclear power reactors.

  3. Parity violation in proton-proton scattering at 230 MEV

    International Nuclear Information System (INIS)

    Birchall, J.; Bowman, J.D.; Davis, C.A.

    1988-01-01

    Below /similar to/300 MeV six meson-nucleon coupling strengths are required to describe the weak interaction of nucleons. Many experiments have found parity-violating effects in nuclear systems, but only four significant, independent constraints exist. A new measurement is proposed where measurable effects are predicted with minimal dependence on nuclear interaction models, yielding information complementary to previous results. This is a measurement of the parity-violating analyzing power. A/sub z/ in p-p scattering at 230 MeV, which is shown to be sensitive to the weak rho-nucleon coupling. This measurement, at a precision of +- 2 x 10/sup -8/, together with a proposed measurement by the University of Washington group at I.L.L. of the parity-violating neutron spin rotation, will provide the fifth and sixth independent constraints needed to determine the weak meson-nucleon coupling constants

  4. Tritium production in thorium by 135 MeV protons

    International Nuclear Information System (INIS)

    Lefort, M.; Simonoff, G.; Tarrago, X.; Bibron, R.

    1960-01-01

    We have measured the cross-section of tritium production by bombardment of thorium by 135 MeV protons in the Orsay synchro-cyclotron. The tritium was separated from the targets by heating in a graphite crucible with a high-frequency generator, under hydrogen gas pressure. Tritiated water was synthesised and the tritium was measured with liquid scintillator. A value of 19.5 ± 0.05 mbarns was obtained for the tritium-cross section and ten percent of tritons have energies higher than 35 MeV. This large cross-section is attributed to a double pick-up process. Reprint of a paper published in Le Journal de Physique et le Radium, t. 20, p. 959, dec 1959 [fr

  5. 0,01-5 MeV heavy ion accelerators

    International Nuclear Information System (INIS)

    Golubev, V.P.; Ivanov, A.S.; Nikiforov, S.A.; Svin'in, M.P.; Tarvid, G.V.; Troshikhin, A.G.; Fedotov, M.T.

    1983-01-01

    The results of development of an accelerating complex on the base of the UP-2-1 heavy ion charge exchange accelerator and IMPLANT-500 high-voltage heavy ion accelerator are given. The accelerating complex provides overlapping of the 0.01 MeV to 5 MeV energy range at accelerated beam currents of 10 -3 -10 -6 A order. The structural features of accelerators and their basic units and systems are considered. The UP-2-1 accelerator is designed for researches in the field of experimental physics and applied problem solutions. The IMPLANT-500 accelerator is designed for commercial ion-beam facilities with closed loop of silicon plate treatment

  6. Operation of the Brookhaven 200 MeV Linac

    International Nuclear Information System (INIS)

    Fewell, N.M.; LoDestro, V.

    1979-01-01

    During the past three years the 200 MeV linear accelerator has continued to operate at a high level of performance and reliability. The linac output beam current has been limited to 60 mA in order to obtain the maximum rf power tube life without compromising the output performance of the AGS. Despite a reduction in pulse repetition rate, total beam current to the BLIP facility has increased to an average of 300 mA hours/year

  7. Construction of 35 MeV DSM at Nihon University

    International Nuclear Information System (INIS)

    Hayakawa, K.; Sato, K.; Tanaka, T.; Takeda, O.

    1988-01-01

    High quality electron beam is needed for the excitation of the free electron laser(FEL). Construction of the 35 MeV double-sided microtron for the FEL has been started at 1984. This accelerator will feed a electron beam which has narrow energy width and low emittance. A first one turn beam line has been completed. Beam accelerating experiments and high power microwave tests are performed. (author)

  8. Thermal Dark Matter Below an MeV

    OpenAIRE

    Berlin, Asher; Blinov, Nikita

    2017-01-01

    We consider a class of models in which thermal dark matter is lighter than an MeV. If dark matter thermalizes with the Standard Model below the temperature of neutrino-photon decoupling, equilibration and freeze-out cools and heats the Standard Model bath comparably, alleviating constraints from measurements of the effective number of neutrino species. We demonstrate this mechanism in a model consisting of fermionic dark matter coupled to a light scalar mediator. Thermal dark matter can be as...

  9. High resolution 14 MeV neutron spectrometer

    International Nuclear Information System (INIS)

    Pillon, M.

    1986-01-01

    A neutron spectrometer, based both on the track position identification and the energy measurement of recoiling protons from a hydrogenous radiator is proposed. The expected performance limits of this spectrometer with regard to energy resolution (deltaE/E), efficiency (epsilon) and counting rate are evaluated in five different configurations. The results show the possibility of deriving an optimized spectrometer design for applications on large fusion devices such as JET and NET with an energy resolution up 1% at 14 MeV

  10. Evolution of the 400 MeV linac design

    International Nuclear Information System (INIS)

    MacLachlan, J.A.

    1987-01-01

    The basic premises of the conceptual design for the linac upgrade are pursued to establish lengths, gradients, power dissipation, etc., for the 400 MeV linac and matching section. The discussion is limited to accelerating and focusing components. Wherever values depend on the choice of the accelerating structure, the disk-and-washer structure is emphasized; the results are generally relevant to the side coupled cavity choice also

  11. 70 MeV injector auto tuning system handbook

    International Nuclear Information System (INIS)

    Ellis, J.E.; Munn, R.W.; Sandels, E.G.

    1976-06-01

    The handbook is in three sections: (1) description and location; (2) operating instructions; and (3) design notes on the tank and debuncher auto tuning systems for the 70 MeV injector. The purpose of the auto tuning system is to maintain the 'tune' of the four tanks and debuncher to within a few Hz, stabilizing against changes of temperature and other physical factors affecting the resonant frequency of the tanks. (U.K.)

  12. Evolution of the 400 MeV linac design

    Energy Technology Data Exchange (ETDEWEB)

    MacLachlan, J.A.

    1987-11-09

    The basic premises of the conceptual design for the linac upgrade are pursued to establish lengths, gradients, power dissipation, etc., for the 400 MeV linac and matching section. The discussion is limited to accelerating and focusing components. Wherever values depend on the choice of the accelerating structure, the disk-and-washer structure is emphasized; the results are generally relevant to the side coupled cavity choice also.

  13. Construction of a pulsed MeV positron beam line

    Energy Technology Data Exchange (ETDEWEB)

    Masuno, Shin-ichi; Okada, Sohei; Kawasuso, Atsuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    To develop a fast (1 MeV) and short pulsed (100 ps) positron beam which enables defect behavior analysis of bulk states of materials even at high temperatures where a usual positron source would melt, we have been performing design study and construction of the beam line in a three-year program since 1994. This report describes the components, design study results and experimental results of the completed parts until now. (author)

  14. Photospallation reactions of 133Cs and 139La by 100 MeV- and 200 MeV bremsstrahlungs

    International Nuclear Information System (INIS)

    Sakamoto, K.; Toramoto, H.; Hamajima, Y.; Okada, K.; Dohniwa, M.

    1984-01-01

    Spallation yields relative to the 196 Au yield from 197 Au(γ,n) of 26 to 46 nuclides of Sb, Te, I, Xe, Cs and/or Ba and La from 133 Cs and 139 La targets irradiated with bremsstrahlungs of end energies of 100 MeV and 200 MeV were radiochemically determined. The isomeric yield ratios for 132 La and 131 Ba from the ( 139 La + 100 MeV-γ), 132 La, 131 Ba, 121 Te and 119 Te from the ( 139 La + 200 MeV-γ, and 120 I, 121 Te and 119 Te from the ( 133 Cs +- 200 MeV-γ) were also determined. The isotopic yields from the (γ,yn) reactions decrease exponentially with increase of y up to 5, and show no dependence on energy and targets studied, indicating that the reactions of a few neutron emissions occur at energies lower than 100 MeV. When the product yields from the (γ,xpyn) reactions were plotted against (x + y) for each x (isotopic distribution), a regular variation of the Gaussian distributions, typical of nuclear spallation, was observed. Isobaric mass distributions and charge dispersions were deduced to extract characteristic features of these reactions. The isobaric distributions due only to photons of 100 MeV to 200 MeV, which were obtained by subtracting the 100 MeV-yields from the 200 MeV-yields, are very close to a symmetric one peaking at about 8 amu from the target masses. Nuclear charges are also dispersed symmetrically, with most probable N/Zsub(p) of about 1.3 replaced by about 1 amu to the neutron-deficient side from the beta stability valley in all the cases studied. Parameters included in Rudstam's semi-empirical formula were examined by comparing with the observed yield curves. The P values of 0.45 and 0.65, chosen for a better fit to the 200 MeV data on 133 Cs and 139 La, respectively, were larger than the predictions reported in the literature. The magic number effects of 139 La may explain the target-differences in mass distributions. (orig.)

  15. Environmental Values (2-MEV and Appreciation of Nature

    Directory of Open Access Journals (Sweden)

    Franz X. Bogner

    2018-01-01

    Full Text Available When monitoring the long history of empirical instruments for environmental attitude measurement, the Two Major Environmental Value model (2-MEV with its two higher order factors: Preservation (PRE and Utilization (UTL has repeatedly and independently been confirmed. PRE assesses preferences towards conservation of nature and the environment, whilst UTL measures preferences towards utilization/exploitation of nature. The latter, however, does not yet include the positive aspects of benefitting from the (enjoyable use of nature. Consequently, besides the established 2-MEV-battery, additional items from an “Appreciation of Nature” (APR scale were applied to an Irish sample of 289 secondary school students (age: M = 14.3 years. Responses to the altogether 30-item battery were applied on an oblique rotation by using the Promax procedure: UTL and PRE appeared as orthogonally related factors, APR correlated to PRE with 0.283. Based on loading scores, the item number for each subscale was further reduced to make the analysis more manageable in educational outreach sites; on those sites, where completing questionnaires may well be quite unpopular, they are very much needed for planning and fine-tuning educational programs. Therefore, extending the 2-MEV scale with an added scale for Appreciation may help: (i to judge participants’ feedback for adjusting/balancing program contents better; and (ii to promote appreciation as a successful strategy for shifting individuals away from their individual exploitative preferences.

  16. Cross sections and analyzing powers of 15N(p,n)15O at 200 MeV and 494 MeV

    International Nuclear Information System (INIS)

    Ciskowski, D.E.

    1989-11-01

    Differential cross sections and analyzing powers have been measured for the 15 N(p,n) 15 O(g.s.) reaction at bombarding energies of 200 MeV and 494 MeV. The 494 MeV data were obtained at the LAMPF Neutron Time-Of-Flight Facility on an 82 m flight path with a resolution of about 2.7 MeV. The 200 MeV data were obtained at IUCF on a 76m flight path with a resolution of about 1.1 MeV. At both energies, the measured analyzing power is small, the magnitude is less than .2 for momentum transfers of less than 1 fm -1 . In contrast, both Relativistic and standard DWIA calculations predict a maximum of A=-.7 near q=0.7 fm -1 . 53 refs., 44 figs

  17. The H(n,n) cross section in the 20 MeV to 350 MeV range

    International Nuclear Information System (INIS)

    1997-01-01

    The differential H(n,n) cross section has been used as a standard relative to which other neutron emission cross sections, e.g., elastic or inelastic scattering, have been measured in several Mev region and these measured values are compared with the VL40 solution of R. Arndt, and R.L. Workman, Nuclear Data Standards for Nuclear Measurements, H. Conde (ed.). NEANDC-311, INDC (SEC)-101, 1992, p. 17. For hydrogen, the differential elastic scattering cross section can be directly related to the total cross section, since no other channels of importance are open below the pion production threshold at about 280 MeV (the capture and Bremsstrahlung cross section are very small). 16 refs, 3 figs

  18. First H- beam accelerated at Linac4: 3MeV done, 157 MeV to go!

    CERN Multimedia

    Linac4 Project Team

    2013-01-01

    On 14 November, the first H- (one proton surrounded by two electrons) beam was accelerated to the energy of 3 MeV in the Linac4 - the new linear accelerator that will replace Linac2 as low-energy injector in the LHC accelerator chain.      A view of the Linac4 taken during the recent tests (top image) and the current measured by the instruments at the end of the acceleration line on 14 November (bottom image). Images: Linac4 collaboration. Using the recently installed Radio Frequency Quadrupole (RFQ) accelerator, 13 mA of current were accelerated to the energy of 3 MeV. After the successful commissioning of the Linac4 RFQ at the 3 MeV test stand completed during the first months of 2013, the whole equipment (composed of the RFQ itself, the following Medium Energy Beam Transport line and its diagnostic line) were moved to the Linac4 tunnel during summer and installed in their final position. In the meantime, a new ion source was assembled, installed and successfu...

  19. 17O(n,α)14C cross section from 25 meV to approximately 1 MeV

    International Nuclear Information System (INIS)

    Koehler, P.E.; Graff, S.M.

    1991-01-01

    We have measured the 17 O(n,α) 14 C cross section from thermal energy to approximately 1 MeV. A bump in the data near 3 keV could be fitted by a state whose properties are consistent with a known subthreshold J π =1 - level at E x =8.039 MeV. The cause of the 1/v cross section near thermal energy could not be determined although the known 2 + state at 8.213 MeV was found to be too narrow to contribute much to the thermal cross section. Our data are compared to measurements made via the inverse reaction. There are many differences between the two sets of data. The astrophysical reaction rate was calculated from the measured cross section. This reaction plays a role in the nucleosynthesis of heavy elements in nonstandard big-bang models. At big-bang temperatures, the experimental rate was found to be in fair agreement with the rate estimated from the previously known properties of states of 18 O in this region. Furthermore, using the available information from experiments, it was estimated that the 17 O(n,α) 14 C rate is approximately a factor of 10 3 --10 4 times larger than the 17 O(n,γ) 18 O rate at big-bang temperatures. As a result, there may be significant cycling between 14 C and 17 O resulting in a reduction of heavy-element nucleosynthesis

  20. Microbeam line of MeV heavy ions for materials modification and in-situ analysis

    International Nuclear Information System (INIS)

    Horino, Yuji; Chayahara, Akiyoshi; Kiuchi, Masato; Fujii, Kanenaga; Satoh, Mamoru; Takai, Mikio.

    1990-01-01

    A microbeam line for MeV heavy ions of almost any element has been developed for microion-beam processing such as maskless MeV ion implantation and its in-situ analysis. Beam spot sizes of 4.0 μm x 4.0 μm for 3 MeV C 2+ and 9.6 μm x 4.8 μm for 1.8 MeV Au 2+ beams were obtained. Maskless MeV gold ion implantation to a silicon substrate and in-situ microanalysis before and after ion implantation were demonstrated. (author)

  1. MeV proton flux predictions near Saturn's D ring.

    Science.gov (United States)

    Kollmann, P; Roussos, E; Kotova, A; Cooper, J F; Mitchell, D G; Krupp, N; Paranicas, C

    2015-10-01

    Radiation belts of MeV protons have been observed just outward of Saturn's main rings. During the final stages of the mission, the Cassini spacecraft will pass through the gap between the main rings and the planet. Based on how the known radiation belts of Saturn are formed, it is expected that MeV protons will be present in this gap and also bounce through the tenuous D ring right outside the gap. At least one model has suggested that the intensity of MeV protons near the planet could be much larger than in the known belts. We model this inner radiation belt using a technique developed earlier to understand Saturn's known radiation belts. We find that the inner belt is very different from the outer belts in the sense that its intensity is limited by the densities of the D ring and Saturn's upper atmosphere, not by radial diffusion and satellite absorption. The atmospheric density is relatively well constrained by EUV occultations. Based on that we predict an intensity in the gap region that is well below that of the known belts. It is more difficult to do the same for the region magnetically connected to the D ring since its density is poorly constrained. We find that the intensity in this region can be comparable to the known belts. Such intensities pose no hazard to the mission since Cassini would only experience these fluxes on timescales of minutes but might affect scientific measurements by decreasing the signal-to-contamination ratio of instruments.

  2. Annealing behaviour of MeV erbium implanted lithium niobate

    Energy Technology Data Exchange (ETDEWEB)

    Gortmaker, P; McCallum, J C [Royal Melbourne Inst. of Tech., VIC (Australia)

    1994-12-31

    Lithium niobate (LiNbO{sub 3}) is a crystalline ceramic commonly used in the fabrication of optoelectronic devices. Recently, rare earth doping of LiNbO{sub 3} has become a topic of particular interest. The electronic configuration of rare earth elements such as Erbium (Er) and Neodymium (Nd) allows them to lase in nearly any host matrix making fabrication of a whole range of new optoelectronic devices possible. At present, the doping technique, for LiNbO{sub 3} are centred upon diffusion technology, but the diffusion profiles for the rare earths are not generally well-matched to the optical modes of the device. The aim of this research is to develop MeV implantation and annealing conditions of rare earth doped LiNbO{sub 3} that would be compatible with optoelectronic device fabrication. To determine the characteristics of the rare earth elements in the LiNbO{sub 3} host material over the depth range of interest in optoelectronic device applications, high energy Rutherford backscattering spectrometry and ion channeling (RBS-C) must be used. Presented here are the Er depth profile and lattice damage results obtained from 5 MeV RBS-C measurements on samples of LiNbO{sub 3} implanted with various doses of MeV Erbium and subsequently thermally annealed at a temperature of 1000 deg C. It was found that there is a peak implant concentration (2 x 10{sup 16} Er/cm{sup 2}) for which erbium no longer goes substitutional in the lattice, and the implantation damage is not fully removed by annealing. 8 refs., 3 figs.

  3. Annealing behaviour of MeV erbium implanted lithium niobate

    Energy Technology Data Exchange (ETDEWEB)

    Gortmaker, P.; McCallum, J.C. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    Lithium niobate (LiNbO{sub 3}) is a crystalline ceramic commonly used in the fabrication of optoelectronic devices. Recently, rare earth doping of LiNbO{sub 3} has become a topic of particular interest. The electronic configuration of rare earth elements such as Erbium (Er) and Neodymium (Nd) allows them to lase in nearly any host matrix making fabrication of a whole range of new optoelectronic devices possible. At present, the doping technique, for LiNbO{sub 3} are centred upon diffusion technology, but the diffusion profiles for the rare earths are not generally well-matched to the optical modes of the device. The aim of this research is to develop MeV implantation and annealing conditions of rare earth doped LiNbO{sub 3} that would be compatible with optoelectronic device fabrication. To determine the characteristics of the rare earth elements in the LiNbO{sub 3} host material over the depth range of interest in optoelectronic device applications, high energy Rutherford backscattering spectrometry and ion channeling (RBS-C) must be used. Presented here are the Er depth profile and lattice damage results obtained from 5 MeV RBS-C measurements on samples of LiNbO{sub 3} implanted with various doses of MeV Erbium and subsequently thermally annealed at a temperature of 1000 deg C. It was found that there is a peak implant concentration (2 x 10{sup 16} Er/cm{sup 2}) for which erbium no longer goes substitutional in the lattice, and the implantation damage is not fully removed by annealing. 8 refs., 3 figs.

  4. Polarization observables in deuteron photodisintegration below 360 MeV

    International Nuclear Information System (INIS)

    2011-01-01

    High precision measurements of induced and transferred recoil proton polarization in d((rvec y), (rvec p))n have been performed for photon energies of 277-357 MeV and θcm = 20 o -120 o . The measurements were motivated by a longstanding discrepancy between meson-baryon model calculations and data at higher energies. At the low energies of this experiment, theory continues to fail to reproduce the data, indicating that either something is missing in the calculations and/or there is a problem with the accuracy of the nucleon-nucleon potential being used.

  5. Polarization observables in deuteron photodisintegration below 360 MeV

    Science.gov (United States)

    Glister, J.; Ron, G.; Lee, B. W.; Gilman, R.; Sarty, A. J.; Strauch, S.; Higinbotham, D. W.; Piasetzky, E.; Allada, K.; Armstrong, W.; Arrington, J.; Arenhövel, H.; Beck, A.; Benmokhtar, F.; Berman, B. L.; Boeglin, W.; Brash, E.; Camsonne, A.; Calarco, J.; Chen, J. P.; Choi, S.; Chudakov, E.; Coman, L.; Craver, B.; Cusanno, F.; Dumas, J.; Dutta, C.; Feuerbach, R.; Freyberger, A.; Frullani, S.; Garibaldi, F.; Hansen, J.-O.; Holmstrom, T.; Hyde, C. E.; Ibrahim, H.; Ilieva, Y.; de Jager, C. W.; Jiang, X.; Jones, M. K.; Kang, Hyekoo; Kelleher, A.; Khrosinkova, E.; Kuchina, E.; Kumbartzki, G.; LeRose, J. J.; Lindgren, R.; Markowitz, P.; May-Tal Beck, S.; McCullough, E.; Meekins, D.; Meziane, M.; Meziani, Z.-E.; Michaels, R.; Moffit, B.; Norum, B. E.; Oh, Y.; Olson, M.; Paolone, M.; Paschke, K.; Perdrisat, C. F.; Potokar, M.; Pomatsalyuk, R.; Pomerantz, I.; Puckett, A.; Punjabi, V.; Qian, X.; Qiang, Y.; Ransome, R. D.; Reyhan, M.; Roche, J.; Rousseau, Y.; Saha, A.; Sawatzky, B.; Schulte, E.; Schwamb, M.; Shabestari, M.; Shahinyan, A.; Shneor, R.; Širca, S.; Slifer, K.; Solvignon, P.; Song, J.; Sparks, R.; Subedi, R.; Urciuoli, G. M.; Wang, K.; Wojtsekhowski, B.; Yan, X.; Yao, H.; Zhan, X.; Zhu, X.

    2011-03-01

    High precision measurements of induced and transferred recoil proton polarization in d(γ→,p→)n have been performed for photon energies of 277-357 MeV and θcm=20°-120°. The measurements were motivated by a longstanding discrepancy between meson-baryon model calculations and data at higher energies. At the low energies of this experiment, theory continues to fail to reproduce the data, indicating that either something is missing in the calculations and/or there is a problem with the accuracy of the nucleon-nucleon potential being used.

  6. The shielding of a 14 MeV neutron generator

    International Nuclear Information System (INIS)

    Brighton, D.R.

    1976-10-01

    The concrete masonry shield for a 14 MeV neutron generator was designed using data supplied by the manufacturer. Subsequent radiation surveys outside the shield showed doses higher than expected. Calculations indicated the sensitivity of dose transmission factors to concrete composition. The observed dose transmission factor agreed with that of Broerse but not with that of Hacke and Prudhomme. Measurements and calculations delineated the contribution that neutrons, scattered from the upper wall that supports the laboratory roof, made to the dose in adjoining areas. In redesigning the shield a compromise was made between additional cost and restrictions on the generator's duty cycle, which is automatically controlled to ensure personnel safety. (Author)

  7. 10 MeV RF electron linac for industrial applications

    International Nuclear Information System (INIS)

    2017-01-01

    Electron linacs have found numerous applications in the field of radiation processing on an industrial scale. High power RF electron linacs are commonly used for food irradiation, medical sterilization, cross-linking of polymers, etc. For this purpose, the 10 MeV RF linac has been indigenously designed, developed, commissioned and is being used regularly at 3 kW beam power. This paper gives a brief description of the linac and its utilization for various applications. Safety considerations and regulatory aspects of the linac are also discussed

  8. Elastic scattering of He$sup 3$ AT 20 Mev

    Energy Technology Data Exchange (ETDEWEB)

    Klingensmith, R. W.; Hausman, H. J.; Ploughe, W. D.

    1963-08-15

    Absolute differential elastic scattering cross sections were measured for the scattering of 20-Mev /sup 3/He particles from V, Ni, Cu, Rh, /sup 118/Sn, Sm, Yb, and Pb. Where practical the measurements were made at laboratory angles extending from 20 to 170 degrees. The diffraction-like oscillations exhibited by the elastic-to-Coulomb cross section ratios are not highly pronounced. A preliminary optical model analysis was carried out using the HUNTER automatic search code of Drisko and Bassel. A Woods-Saxon potential with Thomas type spin-orbit coupling was considered. Reasonable fits to the data were obtained. (auth)

  9. 14MeV facility and research in IPPE

    Energy Technology Data Exchange (ETDEWEB)

    Simakov, S P; Androsenko, A A; Androsenko, P A; Devkin, B V; Kobozev, M G; Lychagin, A A; Sinitca, V V; Talalaev, V A [Institute of Physics and Power Engineering, Obninsk (Russian Federation); Chuvilin, D Yu; Borisov, A A; Zagryadsky, V A [Institute of Atomic Energy, Moscow (Russian Federation)

    1993-07-01

    Review of experimental facility and research, performed at 14MeV incident neutron energy in the Institute of Physics and Power Engineering, are given. These studies cover the next topics: double differential neutron emission cross sections (DDX), neutron-gamma coincidence experiments (n, n'{gamma}) and neutron leakage spectra for spherical assemblies (benchmark). The paper contains description and main parameters of pulsed neutron generator KG-0.3, fast neutron time of flight spectrometer, measuring and data reduction procedures, review of experimental data. Results of experiments are compared with other data; evaluated data files BROND-2, ENDF/B6, JENDL-3; basic theoretical and transport model calculations. (author)

  10. 14MeV facility and research in IPPE

    International Nuclear Information System (INIS)

    Simakov, S.P.; Androsenko, A.A.; Androsenko, P.A.; Devkin, B.V.; Kobozev, M.G.; Lychagin, A.A.; Sinitca, V.V.; Talalaev, V.A.; Chuvilin, D.Yu.; Borisov, A.A.; Zagryadsky, V.A.

    1993-07-01

    Review of experimental facility and research, performed at 14MeV incident neutron energy in the Institute of Physics and Power Engineering, are given. These studies cover the next topics: double differential neutron emission cross sections (DDX), neutron-gamma coincidence experiments (n, n'γ) and neutron leakage spectra for spherical assemblies (benchmark). The paper contains description and main parameters of pulsed neutron generator KG-0.3, fast neutron time of flight spectrometer, measuring and data reduction procedures, review of experimental data. Results of experiments are compared with other data; evaluated data files BROND-2, ENDF/B6, JENDL-3; basic theoretical and transport model calculations. (author)

  11. Reorientation effects for 52 MeV vector polarized deuterons

    International Nuclear Information System (INIS)

    Nurzynski, J.; Kihm, T.; Knopfle, K.T.; Mairle, G.; Clement, H.

    1987-01-01

    The differential cross sections and the vector analysing powers were measured for the elastic and inelastic scattering of 52 MeV vector polarized deuterons from 20 Ne, 22 Ne, 26 Mg, 28 Si, 32 S, 34 S, 36 Ar and 40 Ar nuclei. Coupled channels analysis was carried out using an axially symmetric rotational model with either prolate or oblate quadrupole deformations for each isotope. Calculations assuming harmonic vibrator model were also carried out. In general, reorientation effects were found to be weak. A global optical model potential containing an imaginary spin-orbit component was found to be the most suitable in describing the experimental data at this energy

  12. Dose determination of 600 MeV proton irradiated specimens

    International Nuclear Information System (INIS)

    Gavillet, D.

    1991-01-01

    The calculation method for the experimental determination of the atomic production cross section from the γ activity measurements are presented. This method is used for the determination of some isotope production cross sections for 600 MeV proton irradition in MANET steel, copper, tungsten, gold and titanium. The results are compared with some calculation. These values are used to determine the dose of specimens irradiated in the PIREX II facility. The results are discussed in terms of the irradiation parameters. A guide for the use of the production cross section determined in the dosimetry experiment are given. (author) tabs., refs

  13. A 600 MeV cyclotron for radioactive beam production

    International Nuclear Information System (INIS)

    Clark, D.J.

    1993-01-01

    The magnetic field design for a 600 MeV proton cyclotron is described. The cyclotron has a single stage, a normal conducting magnet coil and a 9.8 m outside yoke diameter. It has 8 sectors, with a transition to 4 sectors in the center region. The magnetic field design was done using 1958 Harwell rectangular ridge system measurements and was compared with recent 3-dimensional field calculations with the program TOSCA at NSCL. The center region 4--8 sector transition focussing was also checked with TOSCA

  14. 160 MeV $H^-$ Injection into the CERN PSB

    CERN Document Server

    Weterings, W; Borburgh, J; Fowler, T; Gerigk, F; Goddard, B; Hanke, K; Martini, M; Sermeus, L

    2007-01-01

    The H- beam from the proposed LINAC4 will be injected into the four existing rings of the PS Booster at 160 MeV. A substantial upgrade of the injection region is required, including the modification of the beam distribution system and the construction of a new H- injection system. This paper discusses beam dynamics and hardware requirements and presents the results of optimisation studies of the injection process for different beam characteristics and scenarios. The resulting conceptual design of the injection region is presented, together with the main hardware modifications and performance specifications.

  15. Status Report on the 5 Mev Iphi RFQ

    OpenAIRE

    Ferdinand, R.; Beauvais, P-Y.; Duperrier, R.; France, A.; Gaiffier, J.; Lagniel, J-M.; Painchault, M.; Simoens, F.; CEA-Saclay; DSM-DAPNIA-SEA; Balleyguier, P.; Chatel, CEA-Bruyeres le; DAM

    2000-01-01

    A 5-MeV RFQ designed for a proton current up to 100-mA CW is now under construction as part of the High Intensity Proton Injector project (IPHI). Its computed transmission is greater than 99 %. The main goals of the project are to verify the accuracy of the design codes, to gain the know-how on fabrication, tuning procedures and operations, to measure the output beam characteristics in order to optimise the higher energy part of the linac, and to reach a high availability with minimum beam tr...

  16. Recoil proton polarization of neutral pion photoproduction from proton in the energy range between 400 MeV and 1142 MeV

    International Nuclear Information System (INIS)

    Kato, S.; Miyachi, T.; Sugano, K.; Toshioka, K.; Ukai, K.

    1979-08-01

    The recoil proton polarization of the reaction γp → π 0 p were measured at a C.M. angle of 100 0 for incident photon energies between 451 and 1106 MeV, and at an angle of 130 0 for energies from 400 MeV to 1142 MeV. One photon decayed from a π 0 -meson and a recoil proton were detected in coincidence. Two kinds of polarization scatterers were employed. In the range of proton kinetic energy less than 420 MeV and higher than 346 MeV, carbon plates and liquid hydrogen were used for determining the polarization. Results are compared with recent phenomenological analyses. From the Comparison between the present data and the asymmetry data given by the polarized target, the contribution of the invariant amplitudes A 3 can be estimated to be small at 100 0 . (author)

  17. High-resolution Auger spectroscopy on 79 MeV Ar5+, 89 MeV Ar6+, and 136 MeV Ar7+ ions after excitation by helium

    International Nuclear Information System (INIS)

    Schneider, T.

    1988-01-01

    In this thesis the atomic structure of highly excited Ar 6+ and Ar 7+ ions was studied. For this 79 MeV Ar 5+ , 89 MeV Ar 6+ , and 136 MeV Ar 7+ ions of a heavy ion accelerator were excited by a He gas target to autoionizing states and the Auger electrons emitted in the decay were measured in highly-resolving state. The spectra were taken under an observational angle of zero degree relative to the beam axis in order to minimize the kinematical broadening of the Auger lines. (orig./HSI) [de

  18. FIRST LIGHT: MeV ASTROPHYSICS FROM THE MOON

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Richard S. [University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, AL 35899 (United States); Lawrence, David J., E-mail: richard.s.miller@uah.edu [Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States)

    2016-06-01

    We report evidence of the first astrophysical source detected from the Moon at MeV energies. Our detection of Cygnus X-1 is a validation of a new investigative paradigm in which the lunar environment is intrinsic to the detection approach: the Lunar Occultation Technique (LOT). NASA’s Lunar Prospector mission served as a proxy for a dedicated LOT-based mission. The characteristic signature of temporal modulation, generated by repeated lunar occultations and encoded within acquired gamma-ray data (0.5–9 MeV), is consistent with an unambiguous detection of Cygnus X-1 at 5.4 σ significance. Source localization and long-term monitoring capabilities of the LOT are also demonstrated. This “first light” detection verifies the basic tenets of the LOT methodology, reinforces its feasibility as an alternative astronomical detection paradigm for nuclear astrophysics investigations, and is an illustration of the fundamental benefits of the Moon as a platform for science.

  19. Risk assessment of 30 MeV cyclotron facilities

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Gyo Seong; Lee, Jin Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Kim, Chong Yeal [Dept. of Radiation Science and Technology, Chonbuk National University, Jeonju (Korea, Republic of)

    2017-03-15

    A cyclotron is a kind of particle accelerator that produces a beam of charged particles for the production of medical, industrial, and research radioisotopes. More than 30 cyclotrons are operated in Korea to produce 18F, an FDG synthesis at hospitals. A 30-MeV cyclotron was installed at ARTI (Advanced Radiation Technology Institute, KAERI) mainly for research regarding isotope production. In this study, we analyze and estimate the items of risk such as the problems in the main components of the cyclotron, the loss of radioactive materials, the leakage of coolant, and the malfunction of utilities, fres and earthquakes. To estimate the occurrence frequency in an accident risk assessment, five levels, i.e., Almost certain, Likely, Possible, Unlikely, and Rare, are applied. The accident consequence level is classified under four grades based on the annual permissible dose for radiation workers and the public in the nuclear safety law. The analysis of the accident effect is focused on the radioactive contamination caused by radioisotope leakage and radioactive material leakage of a ventilation filter due to a free. To analyze the risks, Occupation Safety and Health Acts is applied. In addition, action plans against an accident were prepared after a deep discussion among relevant researchers. In this acts, we will search for hazard and introduce the risk assessment for the research 30-MeV cyclotron facilities of ARTI.

  20. Zone plate imaging of 14-MeV neutrons

    International Nuclear Information System (INIS)

    Lerche, R.A.; Lane, S.M.; Hawryluk, A.M.; Ceglio, N.M.

    1986-01-01

    At Livermore we are interested in imaging the thermonuclear burn region of fusion targets irradiated at our Nova laser facility. We expect compressed core diameters to be 10's of microns, and would like images with better than 10-μm resolution. Alpha particle images provided the first direct information about the thermonuclear burn geometry in thin walled exploding pusher targets. In future high density target experiments, only highly penetrating radiations like the 14-MeV neutrons will escape the target core to provide information about the burn region. To make the measurement with a neutron ''pinhole'' camera requires a 10μm pinhole through about 10 cm of material and 10 14 to 10 15 source neutrons. Penumbral imaging offers some improvement over a pinhole. Zone plate coded imaging (ZPCI) techniques are particularly well suited for imaging small objects like the compressed core of a laser fusion target. We have been using ZPCI techniques to image nonpenetrating radiations like x rays and alpha particles for about 10 years. The techniques are well developed. Imaging penetrating radiations like 14-MeV neutrons using ZPCI techniques has several possible advantages. The large solid angle subtended by the Zone plate might substantially reduce the required target neutron yield needed to produce a useful image, and a neutron zone plate system with 10-μm resolution might be easier to fabricate and characterize than a pinhole system. This paper explores the use of ZPCI techniques with penetrating radiation

  1. Risk assessment of 30 MeV cyclotron facilities

    International Nuclear Information System (INIS)

    Jeong, Gyo Seong; Lee, Jin Woo; Kim, Chong Yeal

    2017-01-01

    A cyclotron is a kind of particle accelerator that produces a beam of charged particles for the production of medical, industrial, and research radioisotopes. More than 30 cyclotrons are operated in Korea to produce 18F, an FDG synthesis at hospitals. A 30-MeV cyclotron was installed at ARTI (Advanced Radiation Technology Institute, KAERI) mainly for research regarding isotope production. In this study, we analyze and estimate the items of risk such as the problems in the main components of the cyclotron, the loss of radioactive materials, the leakage of coolant, and the malfunction of utilities, fres and earthquakes. To estimate the occurrence frequency in an accident risk assessment, five levels, i.e., Almost certain, Likely, Possible, Unlikely, and Rare, are applied. The accident consequence level is classified under four grades based on the annual permissible dose for radiation workers and the public in the nuclear safety law. The analysis of the accident effect is focused on the radioactive contamination caused by radioisotope leakage and radioactive material leakage of a ventilation filter due to a free. To analyze the risks, Occupation Safety and Health Acts is applied. In addition, action plans against an accident were prepared after a deep discussion among relevant researchers. In this acts, we will search for hazard and introduce the risk assessment for the research 30-MeV cyclotron facilities of ARTI

  2. Shielding measurements for a 230 MeV proton beam

    International Nuclear Information System (INIS)

    Siebers, J.V.

    1990-01-01

    Energetic secondary neutrons produced as protons interact with accelerator components and patients dominate the radiation shielding environment for proton radiotherapy facilities. Due to the scarcity of data describing neutron production, attenuation, absorbed dose, and dose equivalent values, these parameters were measured for 230 MeV proton bombardment of stopping length Al, Fe, and Pb targets at emission angles of 0 degree, 22 degree, 45 degree, and 90 degree in a thick concrete shield. Low pressure tissue-equivalent proportional counters with volumes ranging from 1 cm 3 to 1000 cm 3 were used to obtain microdosimetric spectra from which absorbed dose and radiation quality are deduced. Does equivalent values and attenuation lengths determined at depth in the shield were found to vary sharply with angle, but were found to be independent of target material. Neutron dose and radiation length values are compared with Monte Carlo neutron transport calculations performed using the Los Alamos High Energy Transport Code (LAHET). Calculations used 230 MeV protons incident upon an Fe target in a shielding geometry similar to that used in the experiment. LAHET calculations overestimated measured attenuation values at 0 degree, 22 degree, and 45 degree, yet correctly predicted the attenuation length at 90 degree. Comparison of the mean radiation quality estimated with the Monte Carlo calculations with measurements suggest that neutron quality factors should be increased by a factor of 1.4. These results are useful for the shielding design of new facilities as well as for testing neutron production and transport calculations

  3. Momentum transfer with light ions at energies from 70 MeV to 1000 MeV

    International Nuclear Information System (INIS)

    Saint Laurent, F.; Conjeaud, M.; Dayras, R.; Harar, S.; Oeschler, H.; Volant, C.

    1982-01-01

    Angular correlations of fission fragments induced by bombarding a 232 Th target with protons, deuterons and alpha particles of energies from 70 MeV to 1000 MeV have been measured. They give information about the forward momentum imparted to the fissioning nuclei. We present the average values of the transferred linear momentum ([p vertical stroke vertical stroke ]) as a function of the incident energy and propose a classification into three regimes of dominating processes leading to fission: (I) low-energy behaviour, for E/A less than 10 MeV/u [p vertical stroke vertical stroke ]/psub(i) approx. equal to 1. (II) Between 10 MeV/u and about 70 MeV/u, [p vertical stroke vertical stroke ]/psub(i) decreases progressively down to 0.5 but remains proportional to the projectile mass. (III) The region between 70 MeV/u and about 1000 MeV/u corresponds to a transition region where the projectiles, whatever their masses, tend to transfer the same momentum. (orig.)

  4. Structural, thermal and optical behavior of 84 MeV oxygen and 120 MeV silicon ions irradiated PES

    International Nuclear Information System (INIS)

    Samra, Kawaljeet Singh; Thakur, Sonika; Singh, Lakhwant

    2011-01-01

    In order to study structural, thermal and optical behavior, thin flat samples of polyethersulfone were irradiated with oxygen and silicon ions. The changes in properties were analyzed using different techniques viz: X-ray diffraction, thermo-gravimetric analysis, Fourier transform infrared, UV-visible and photoluminescence spectroscopy. A noticeable increase in the intensity of X-ray diffraction peaks was observed after irradiation with 84 MeV oxygen ions at low and medium fluences, which may be attributed to radiation-induced cross-linking in polymer. Fourier transform infrared and thermo-gravimetric analysis corroborated the results of X-ray diffraction analysis. No noticeable change in the Fourier transform infrared spectra of oxygen ion irradiated polyethersulfone were observed even at the highest fluence of 1 x 10 13 ions cm -2 , but after irradiation with silicon ions, a reduction in intensity of almost all characteristic bands was revealed. An increase in the activation energy of decomposition of polyethersulfone was observed after irradiation with 84 MeV oxygen ions up to medium fluences but degradation was revealed at higher fluences. Similar trends were observed by photoluminescence analysis.

  5. Elastic scattering for 16O + 12C at 140 MeV and 218 MeV

    International Nuclear Information System (INIS)

    Galindo U, A.

    1981-01-01

    In this work, angular distribution of cross sections have been measured for 12 C( 16 O, 16 O) 12 C at two energies. The measurements were carried out in 0.5 0 intervals between 5 0 -19.5 0 C (lab.) at 140 MeV, 4.5 0 -14.5 0 at 218 MeV. An optical model analysis of these strong structure angular distributions was done. Good fits of the data were obtained using the optical model search code GENOA with a full Woods-Saxon potential form. This yielded parameters subject to considerable ambiguities as it is known to occur for strongly absorbed particles. These ambiguities were explored in detail and it was found that both the real and the imaginary parts present some characteristics that have been found before for the real potential (as Igo relation for continous ambiguities and the fact that potentials with different diffusivities tend to have the same value at the strong absorption radii). It was found, among other results, that the real volume integral, the mean square radius, as well as the total reaction cross section (σsub(r)) cannot be determined unambiguously. A strong correlation was found between σsub(r) and the imaginary diffusivity. A systematic study of how the variation of the potential parameters affects the angular distribution is presented and some features of the diffraction structure of the angular distribution are discussed. (author)

  6. Elastic scattering of polarized protons by 20Ne between 4.5 Mev and 5.5 Mev

    International Nuclear Information System (INIS)

    Avila A, O.L.

    1979-01-01

    Starting with the study of 20 Ne(p,p) 20 nuclear reaction, we obtained information about the nuclear structure of 21 Na. The experiment was made at Notre Dame University; a target of 20 Ne was bombarded with polarized protons, changing the incident energy of them between 4.5 Mev and 5.5 Mev at intervals of 10 keV. Fourteen detectors were set covering angles from 35 degrees until 165 degrees, with intervals of 10 degrees each. In this form measurements for computing polarization and differential sections were obtained, with them an analysis of runnings of phase was made, and the parameters associated with two of the excited levels of the composed formed nucleous 21 Na, that are viewed as resonances in the section were settled; those resonances correspond to a level Psub(3/2) of energy excitation 6.877, a total width of 36 keV, and a level Fsub(7/2) of energy excitation 6.992 and total width of 48 keV. I hope that these results will be part of a set of values that will be utilized in order to confront them with the existent nuclear models. (author)

  7. Enhanced diffusion of dopants in vacancy supersaturation produced by MeV implantation

    International Nuclear Information System (INIS)

    Venezia, V.C.; Univ. of North Texas, Denton, TX; Haynes, T.E.; Agarwal, A.; Lucent Technologies, Murray Hill, NJ; Gossmann, H.J.; Eaglesham, D.J.

    1997-04-01

    The diffusion of Sb and B markers has been studied in vacancy supersaturations produced by MeV Si implantation in float zone (FZ) silicon and bonded etch-back silicon-on-insulator (BESOI) substrates. MeV Si implantation produces a vacancy supersaturated near-surface region and an interstitial-rich region at the projected ion range. Transient enhanced diffusion (TED) of Sb in the near surface layer was observed as a result of a 2 MeV Si + , 1 x 10 16 /cm 2 , implant. A 4x larger TED of Sb was observed in BESOI than in FZ silicon, demonstrating that the vacancy supersaturation persists longer in BESOI than in FZ. B markers in samples with MeV Si implant showed a factor of 10x smaller diffusion relative to markers without the MeV Si + implant. This data demonstrates that a 2 MeV Si + implant injects vacancies into the near surface region

  8. Fission cross section measurements at the LLL 100-MeV linac

    International Nuclear Information System (INIS)

    Browne, J.C.

    1975-01-01

    The fission cross section for 235 U was measured from thermal energy to 20 MeV in several steps. First, the cross section was measured from 8 MeV to 20 MeV relative to the n,p scattering cross section and then from thermal to one MeV relative to 6 Li(n,α). In addition, a measurement of the ratio of the fission cross sections of 235 U and 238 U relative to 235 U has been completed in the range 1 keV to 30 MeV for 233 U and 100 keV to 30 MeV for 238 U. Statistical uncertainties are less than 4 percent. (U.S.)

  9. RBE comparison between rapid electrons of 20 MeV and 45 MeV with survival rate, DNA synthesis, DNA reparation and nucleoid sedimentation

    International Nuclear Information System (INIS)

    Alth, G.; Weniger, P.; Turtzer, K.; Klein, W.; Kocsis, F.; Krankenhaus der Stadt Wien-Lainz; Oesterreichisches Forschungszentrum Seibersdorf G.m.b.H. Inst. fuer Biologie)

    1982-01-01

    In order to find out possible differences of the biologic efficacy of rapid electrons of different energies, the authors examined the influence of rapid electrons of 20 MeV and 45 MeV upon the survival rate of Hela cells S3, their cell growth, DNA synthesis, DNA reparation, and sedimentation of nucleoids. The results show a difference only for the nucleoid sedimentation, i.e. there are more fractured DNA cords after 45 MeV irradiation. No significant differences could be demonstrated for the parameters of the survival curve, DNA synthesis and DNA reparation. Four double tests were carried out corresponding to the indicated types of examination. (orig.) [de

  10. Thermal Dark Matter Below a MeV.

    Science.gov (United States)

    Berlin, Asher; Blinov, Nikita

    2018-01-12

    We consider a class of models in which thermal dark matter is lighter than a MeV. If dark matter thermalizes with the standard model below the temperature of neutrino-photon decoupling, equilibration and freeze-out cool and heat the standard model bath comparably, alleviating constraints from measurements of the effective number of neutrino species. We demonstrate this mechanism in a model consisting of fermionic dark matter coupled to a light scalar mediator. Thermal dark matter can be as light as a few keV, while remaining compatible with existing cosmological and astrophysical observations. This framework motivates new experiments in the direct search for sub-MeV thermal dark matter and light force carriers.

  11. Focussed MeV ion beam implanted waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Von Bibra, M L; Roberts, A; Nugent, K; Jamieson, D N [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1997-12-31

    Single mode buried optical waveguides have been fabricated in fused silica by MeV proton implantation using a focussed hydrogen ion beam. The technique has the potential to direct write waveguide devices and produce multi-layered structures, without the need for intermediate steps such as mask fabrication or layered depositions. A micron resolution Confocal Raman Spectrometer has been used to map the distribution of atomic vacancies that forms the waveguiding region. The results are compared with theoretical calculations. Losses of 3 dB cm{sup -1} have been measured in unannealed samples, which decreases to less than 0.5 dB cm{sup -1} after annealing at 500 degrees Celsius. We describe methods for determining the refractive index distribution of single mode buried waveguides from their output intensity distributions via an inversion of the scalar wave equation. (authors). 5 figs.

  12. Focussed MeV ion beam implanted waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Von Bibra, M.L.; Roberts, A.; Nugent, K.; Jamieson, D.N. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    Single mode buried optical waveguides have been fabricated in fused silica by MeV proton implantation using a focussed hydrogen ion beam. The technique has the potential to direct write waveguide devices and produce multi-layered structures, without the need for intermediate steps such as mask fabrication or layered depositions. A micron resolution Confocal Raman Spectrometer has been used to map the distribution of atomic vacancies that forms the waveguiding region. The results are compared with theoretical calculations. Losses of 3 dB cm{sup -1} have been measured in unannealed samples, which decreases to less than 0.5 dB cm{sup -1} after annealing at 500 degrees Celsius. We describe methods for determining the refractive index distribution of single mode buried waveguides from their output intensity distributions via an inversion of the scalar wave equation. (authors). 5 figs.

  13. Sustained performance of 8 MeV Microtron

    International Nuclear Information System (INIS)

    Sanjeev, Ganesh

    2012-01-01

    Energetic electrons and intense bremsstrahlung radiation from 8 MeV Microtron are being utilized in variety of collaborative research programs in radiation physics and allied sciences involving premier institutions of the country and sister universities of the region. The first of its kind electron accelerator in the country, set up at Mangalore University in collaboration with RRCAT Indore and BARC Mumbai, has been facilitating researchers since its inception with its inherent simplicity, ease of construction, low cost and excellent beam quality. A bird's eye view on the reliable aspects of the machine, efforts behind the continuous operation of the accelerator and important applications of the accelerator in physical and biological sciences are presented in this paper.

  14. Multipole Stack for the 800 MeV PS Booster

    CERN Multimedia

    1975-01-01

    The 800 MeV PS Booster had seen first beam in its 4 superposed rings in 1972, routine operation began in 1973. In the strive for ever higher beam intensities, the need for additional multipole lenses became evident. After detailed studies, the manufacture of 8 stacks of multipoles was launched in 1974. Each stack consists of 4 superposed multipoles and each multipole has 4 concentric shells. From the innermost to the outermost shell, Type A contains octupole, skew-octupole, sextupole, skew-sextupole. Type B contains skew-octupole, skew-sextupole, vertical dipole, horizontal dipole. Completion of installation in 1976 opened the way to higher beam intensities. M. Battiaz is seen here with a multipole stack and its many electrical connections.

  15. Control system for 10 MeV irradiation electron linac

    International Nuclear Information System (INIS)

    Zeng Ziqiang; Zhang Lifeng; Lu Weixing; Gao Zhenjiang; Zhang Yan; Han Guangwen; Wang Shuxian

    2005-01-01

    Control system of the 10 MeV electron linac using Distributed Control System (DCS) was studied. The hardware of control system consists of four SIEMENS PLCs and monitor computer, the software bases on STEP 7, Labwindows/CVI and SQL Server. The bus between the monitor computer and the main PLC is 100 M industrial networks, between PLCs is MPI bus, between PLC and remote partner is PROFIBUS, between PLC and terminals is RS485/422. The software of control system can provide a friendly human machine interface to operate the machine, protect the human and equipment from risk, and storage the status of the accelerator real time to the database. The monitor and maintenance of the linac can been carried out not only on local computer or local network, but also in internet. (author)

  16. The 50 MeV Beam Test Facility at LBL

    International Nuclear Information System (INIS)

    Leemans, W.; Behrsing, G.; Kim, K.J.; Krupnick, J.; Matuk, C.; Selph, F.; Chattopadhyay, S.

    1993-05-01

    A new beam line, expected to be built by September 1993, will transport the 50 MeV electron beam from the ALS LINAC into an experimental area to support various R ampersand D activities in the Center for Beam Physics at LBL. A variety of experiments are planned involving the interaction of such a relativistic electron beam with plasmas (plasma focusing), laser beams (generation of femtosecond X-ray pulses) and electromagnetic cavities (Crab cavities etc....). The beam line is designed using the measured emittance and Twiss parameters of the ALS linac. It accommodates the different requirements of the various experiments on the electron beam properties (charge, energy, pulse length) and on the handling of the beam before and after the interaction point. Special attention has also been given to incorporate diagnostics for measuring the beam properties (such as the electron energy, bunch length and charge) needed in the interpretation of the experiments

  17. 200-MeV bremsstrahlung tagged photon beams at Sendai

    International Nuclear Information System (INIS)

    Hirose, K.; Chiba, M.; Inoue, M.; Kanda, H.; Kimura, R.; Kino, K.; Kobayashi, Y.; Konno, O.; Maeda, K.; Miyase, H.; Miyamoto, A.; Ohtsuki, T.; Saito, A.; Suda, T.; Takahashi, K.; Tamae, T.; Terasaki, Y.; Terasawa, T.; Tsubota, H.; Tsuruta, T.; Utoyama, M.; Yuuki, H.; Yamaguchi, Y.; Yamazaki, H.

    2006-01-01

    A new beam line for photonuclear reaction experiments using tagged photons has been constructed to take advantage of the completion of the 1.2-GeV STretcher Booster (STB) ring at the Laboratory of Nuclear Science (LNS), Tohoku University. A photon tagging system was installed at the end of the new beam line. It provides bremsstrahlung tagged photon beams in an energy range from 0.2E 0 to 0.8E 0 MeV at the incident electron energy E 0 with an energy resolution of ΔE/E∼10 -2 . The tagged photon intensity I= 6 photons/s is available for typical photonuclear reaction experiments. We introduce the basic parameters of the tagged photons by showing the commissioning data

  18. Shielding calculations for a 30 MeV proton accelerator

    International Nuclear Information System (INIS)

    Nandy, Maitreyee; Sarkar, P.K.

    2003-01-01

    Full text: The thickness of the shield, made of ordinary concrete, required to reduce the equivalent dose rate below the maximum permissible limit and to ensure safe operation of a 30 MeV proton accelerator has been estimated using the Moyer model. Required double differential neutron yield from thick stopping targets has been calculated for several reactions to be used for production of 67 Ga, 111 In, 123 I and 201 Tl radioisotopes. The neutron emission at 0 deg and 90 deg angles with respect to the incident beam direction is estimated using the hybrid model code ALICE91 which considers preequilibrium and equilibrium emissions from the target+projectile composite system. From this neutron yield the equivalent neutron dose rate at unit distance is determined using the ICRP recommended flux-to-dose conversion factors

  19. Little Boy neutron spectrum below 3 MeV

    International Nuclear Information System (INIS)

    Evans, A.E.; Bennett, E.F.; Yule, T.J.

    1984-01-01

    The leakage neutron spectrum from the Little Boy replica has been measured from 12 keV to 3 MeV using a high-resolution 3 He ionization chamber, and from 1 keV to 3 MeV using proton-recoil proportional counters. The 3 He-spectrometer measurements were made at distances of 0.75 and 2.0 m from the active center and at angles of 0 0 , 45 0 , and 90 0 with respect to the axis of the assembly. Proton-recoil measurments were made at 90 0 to the assembly axis at distances of 0.75 and 2.0 m, with a shielded measurement made at 2.0 m to estimate background due to scattering. The 3 He spectrometer was calibrated at Los Alamos using monoenergetic 7 Li(p,n) 7 Be neutrons to generate a family of response functions. The proton-recoil counters were calibrated at Argonne by studying the capture of thermal neutrons by nitrogen in the counters, by observation of the 24-keV neutron resonance in iron, and by relating to the known hydrogen content of the counters. The neutron spectrum from Little Boy was found to be highly structured, with peaks corresponding to minima in the iron total neutron cross section. In particular, influence of the 24-keV iron window was evident in both sets of spectra. The measurements provide information for dosimetry calculations and also a valuable intercomparison of neutron spectrometry using the two different detector types. Spectra measured with both detectors are in essential agreement. 8 references, 7 figures, 2 tables

  20. Neutron-induced fission cross sections of uraniums up to 40 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus); Hasegawa, A.

    1998-11-01

    Statistical theory of nuclear reactions, well-proved below 20 MeV, is applied for {sup 235}U and {sup 238}U fission data analysis up to {approx}40 MeV. It is shown that measured data could be reproduced. Chance structure of measured fission cross section is provided, it`s validity is supported by description of data for competing (n,xn)-reactions. Role of fissility of target nucleus is addressed. It seems that gap in incident neutron energy interval of 20 MeV - 50 MeV, below which evaluation approaches are well-developed, and above which simplified statistical approaches are valid, could be covered. (author)

  1. Monte Carlo 20 and 45 MeV Bremsstrahlung and dose-reduction calculations

    Energy Technology Data Exchange (ETDEWEB)

    Goosman, D.R.

    1984-08-14

    The SANDYL electron-photon coupled Monte Carlo code has been compared with previously published experimental bremsstrahlung data at 20.9 MeV electron energy. The code was then used to calculate forward-directed spectra, angular distributions and dose-reduction factors for three practical configurations. These are: 20 MeV electrons incident on 1 mm of W + 59 mm of Be, 45 MeV electrons of 1 mm of W and 45 MeV electrons on 1 mm of W + 147 mm of Be. The application of these results to flash radiography is discussed. 7 references, 12 figures, 1 table.

  2. Monte Carlo 20 and 45 MeV Bremsstrahlung and dose-reduction calculations

    International Nuclear Information System (INIS)

    Goosman, D.R.

    1984-01-01

    The SANDYL electron-photon coupled Monte Carlo code has been compared with previously published experimental bremsstrahlung data at 20.9 MeV electron energy. The code was then used to calculate forward-directed spectra, angular distributions and dose-reduction factors for three practical configurations. These are: 20 MeV electrons incident on 1 mm of W + 59 mm of Be, 45 MeV electrons of 1 mm of W and 45 MeV electrons on 1 mm of W + 147 mm of Be. The application of these results to flash radiography is discussed. 7 references, 12 figures, 1 table

  3. Search for an elusive 4.4-MeV α emitter in uranium minerals

    International Nuclear Information System (INIS)

    Dougan, R.J.; Illige, J.D.; Hulet, E.K.

    1979-12-01

    A search for an unidentified 4.4-MeV α-emitter in Belgian Congo pitchblende and uranium raffinates is described, and a history of observations of 4.4-MeV activity over the last 55 years in radiogenic haloes, zinc ores, monazite, thorite, huttonite, ultrabasic and other abyssal rocks, osmiridium, uranium ores, and raffinates of uranium is given. No evidence of excess 4.4-MeV activity was shown in any of the chemically separated fractions investigated. Upper limits for 4.4-MeV α activity in each of four studied samples are given

  4. A comparative study of 30MeV boron4+ and 60MeV oxygen8+ ion irradiated Si NPN BJTs

    International Nuclear Information System (INIS)

    Kumar, M. Vinay; Krishnaveni, S.; Yashoda, T.; Dinesh, C. M.; Krishnakumar, K. S.; Jayashree, B.; Ramani

    2015-01-01

    The impact of 30MeV boron 4+ and 60MeV oxygen 8+ ion irradiation on electrical characteristics of 2N3773 Si NPN Bipolar junction transistors (BJTs) is reported in the present study. The transistors were decapped and irradiated at room temperature. Gummel characteristics, DC current gain and Capacitance-voltage (C-V) characteristics were studied before and after irradiation at different fluences. DC current gain has decreased significantly in both boron and oxygen ion irradiation. Also the value of capacitance decreased 3-4 times with increase in fluence. Both 30MeV boron ion and 60MeV oxygen ion induced similar extent of degradation in electrical characteristics of the transistor

  5. Emission of light charged particles from fragments produced on fission of uranium nuclei by 153 MeV protons and 1700 MeV negative pions

    International Nuclear Information System (INIS)

    Belovitzky, G.E.; Shteingrad, O.M.

    2000-01-01

    The mechanism underlying the emission of light charged particles (LCP) with Z = 1, 2 from fragments produced in fission of uranium nuclei by 153 MeV protons and 1700 MeV negative pions was studied. It was found that LCP accompanying the fission by pions are emitted from non-accelerated fragments immediately after the fission, whereas in the case of 153 MeV protons, the LCP are emitted from the accelerated heavy fragments. The number of LCP emitted in the course of pion-induced fission is 0.7 per fission event, which exceeds by a factor of 30 the corresponding number for 153 MeV protons [ru

  6. Characterisation of a compton suppressed clover detector for high energy gamma rays (5 MeV ≤ E ≤ 11 MeV)

    International Nuclear Information System (INIS)

    Saha Sarkar, M.; Kshetri, Ritesh; Raut, Rajarshi; Mukherjee, A.; Goswami, A.; Ray, S.; Basu, P.; Majumder, H.; Bhattacharya, S.; Dasmahapatra, B.; Sinha, Mandira; Ray, Maitreyee

    2004-01-01

    The Clover detectors in their add back mode have been seen to be excellent tools for detecting high energy gamma rays (≥ 2 MeV). Recently studies were carried out on the characteristics of a Compton suppressed Clover germanium detector up to 5 MeV using a radioactive 66 Ga (T 1/2 =9.41 h) source for the first time

  7. Inelastic proton scattering at 800 MeV to the 12C 15.11-MeV state: A search for nuclear critical opalescence

    International Nuclear Information System (INIS)

    Haji-Saeid, M.; Glashausser, C.; Igo, G.; Cornelius, W.; Gazzaly, M.; Irom, F.; McClelland, J.; Moss, J.M.; Pauletta, G.; Thiessen, H.A.; Whitten, C.A. Jr.

    1980-01-01

    The differential cross section for the reaction 12 C(p,p') 12 C* (15.11 MeV, 1 + , T=1) has been measured at 800 MeV; the range of the angular distribution corresponds to momentum transfers of 0.7--2.4 fm -1 [(1-3.3)m/sub π/]. The cross section decreases almost exponentially at large angles; no maximum is observed in the region where nuclear critical opalescence might be expected

  8. Formation of Cavities at and Away from Grain Boundaries during 600 MeV Proton Irradiation

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Leffers, Torben; Green, W. V.

    1982-01-01

    High-purity aluminium (99.9999%) was irradiated with 600 MeV protons at the Swiss Institute for Nuclear Research (SIN) with a damage rate of 3,5 x 10^-6 dpa/s. Irradiation with 600 MeV protons produces helium, hydrogen, and other impurities through mutational reactions. The irradiation experiment...

  9. Production of 14 MeV neutrons from D-D neutron generators

    International Nuclear Information System (INIS)

    Cecil, F.E.; Nieschmidt, E.B.

    1986-01-01

    The production of 14 MeV neutrons from a D-D neutron generator resulting from tritium buildup from the d(d,p)t reaction in the target is discussed. The effect of the 14 MeV neutrons on fast neutron activation analysis with D-D neutron generators is evaluated. (orig.)

  10. Klystron High Power Operation for KOMAC 100-MeV Proton Linac

    Energy Technology Data Exchange (ETDEWEB)

    Seol, Kyung-Tae; Kim, Seong-Gu; Kwon, Hyeok-Jung; Kim, Han-Sung; Cho, Yong-Sub [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    The Korea multi-purpose accelerator complex (KOMAC) accelerator facility has a 100-MeV proton linac, five beam lines for 20-MeV beam utilization, and another five beam lines for 100-MeV beam utilization. The 100-MeV linac consists of a 50-keV proton injector based on a microwave ion source, a 3-MeV RFQ with a four-vane structure, and a 100-MeV DTL. Nine sets of 1MW klystrons have been operated for the 100-MeV proton linac. The klystron filament heating time was approximately 5700 hours in 2014, and RF operation time was 2863.4 hours. During the high power operation of the klystron, unstable RF waveforms appeared at the klystron output, and we have checked and performed cavity frequency adjustments, magnet and heater current, reflection from a circulator, klystron test without a circulator, and the frequency spectrum measurement. Nine sets of the klystrons have been operated for the KOMAC 100-MeV proton linac. The klystron filament heating time was 5700 hours and RF operation time was 2863.4 hours during the operation in 2014. Some klystrons have unstable RF waveforms at specific power level. We have checked and tested the cavity frequency adjustment, reflection from a circulator, high power test without a circulator, and frequency spectrum at the unstable RF.

  11. 75 FR 1527 - Special Conditions: Bombardier, Inc., Model DHC-8-100, -200, -300, and -400 Series Airplanes...

    Science.gov (United States)

    2010-01-12

    ..., Standardization Branch, ANM-113, Transport Airplane Directorate, Aircraft Certification Service, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 227-22793 facsimile (425) 227-1230; or e-mail... December 28, 2009. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service...

  12. 75 FR 10658 - Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500...

    Science.gov (United States)

    2010-03-09

    ... structure. DATES: This AD becomes effective April 13, 2010. The Director of the Federal Register approved... CONTACT: Wayne Lockett, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification... on pressurized fuselage structure. Compliance (f) You are responsible for having the actions required...

  13. 75 FR 43803 - Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500...

    Science.gov (United States)

    2010-07-27

    ... air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds.../baking cycle must not exceed 0.002-inches-per-hour. (2) Begin the hydrogen embrittlement relief bake... carriage spindle. Alternative Methods of Compliance (AMOCs) (t)(1) The Manager, Seattle Aircraft...

  14. 76 FR 63229 - Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500...

    Science.gov (United States)

    2011-10-12

    ... potential for ignition sources inside fuel tanks caused by latent failures, alterations, repairs, or... automatic shutoff system for the center and auxiliary tank fuel boost pumps, as applicable, and installing a... installing the un-commanded on (UCO) protection system for the center and auxiliary tank fuel boost pumps, as...

  15. 75 FR 8554 - Airworthiness Directives; The Boeing Company Model 747-100, -200B, and -200F Series Airplanes

    Science.gov (United States)

    2010-02-25

    ...-0132; Directorate Identifier 2009-NM-096-AD] RIN 2120-AA64 Airworthiness Directives; The Boeing Company... approaching or have exceeded their design life goal. We issued that AD to prevent separation of fuselage skin...,000 flight cycles to 1,000 flight cycles. Differences Between the Proposed AD and Service Bulletin...

  16. 75 FR 9137 - Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500...

    Science.gov (United States)

    2010-03-01

    ... AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. Examining the... repetitive detailed and magnetic particle inspections to detect discrepancies (including corrosion, pitting... detailed inspection for corrosion, pitting, and cracking of the carriage spindle, the magnetic particle...

  17. Polarization measurements for P-12C elastic scattering between 40-75 MeV

    International Nuclear Information System (INIS)

    Kato, S.; Okada, K.; Kondo, M.; Shimizu, A.; Hosono, K.; Saito, T.; Matsuoka, N.; Nagamachi, S.; Nisimura, K.; Tamura, N.

    1980-01-01

    Absolute values of the polarization in p- 12 C elastic scattering have been measured at 60.0 and 64.5 MeV at 47.5 0 in the laboratory system using a double scattering method and a method to measure an asymmetry with a polarized beam. The results are P(60.0 MeV, 47.5 0 ) = 0.965 +- 0.011 and P(64.5 MeV, 47.5 0 ) = 0.975 +- 0.011. Based on these values, the polarization measurements have been extended to the energy range from 40-75 MeV at several angles around 47.5 0 using the polarized proton beam and the energy degrader. Differential cross sections and polarizations from 15-115 0 are also presented at 65 MeV. These data will be valuable for the monitoring of beam polarization in this energy region. (orig.)

  18. p-p analyzing power excitation function between 510 and 725 MeV

    International Nuclear Information System (INIS)

    Beurtey, R.; Arvieux, J.; Boivin, M.; Boyard, J.L.; Durand, J.M.; Combes-Comets, M.P.; Courtat, P.; Gacougnolle, R.; Le Bornec, Y.; Garcon, M.

    1993-01-01

    In an earlier experiment some evidence was observed for narrow dibaryons in the analyzing power excitation function of p-p elastic scattering at √s=2160 MeV and 2192 MeV, with width Γ≅13-14 MeV. A different procedure has been carried out at the SATURNE synchrotron, in order to obtain a very high accuracy of the analyzing power for a large number of energies between 510 and 725 MeV. The results show no evidence for any structure with width ∼5 to 20 MeV. The reasons at the difference between the two experiments are discussed. (K.A.) 2 refs., 3 figs

  19. Study of two photon production process in proton-proton collisions at 216 MeV

    International Nuclear Information System (INIS)

    Khrykin, A.S.

    2002-01-01

    The energy spectrum for high energy γ-rays (Eγ ≥ 10 MeV) from the process pp → γγX emitted at 90 deg. in the laboratory frame has been measured at 216 MeV. The resulting photon energy spectrum extracted from γ - γ coincidence events consists of a narrow peak (5.3σ) at a photon energy of about 24 MeV and a relatively broad peak (3.5σ) in the energy range of (50 - 70) MeV. This behavior of the photon energy spectrum is interpreted as a signature of the exotic dibaryon resonance d 1 * with a mass of about 1956 MeV which is assumed to be formed in the radiative process pp → γd 1 * followed by its electromagnetic decay via the d 1 * → ppγ mode. The experimental spectrum is compared with those obtained by means of Monte Carlo simulations

  20. Multipurpose 5-MeV linear induction accelerator

    International Nuclear Information System (INIS)

    Birx, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Smith, M.W.

    1984-01-01

    Although linear induction accelerators (LIAs) are quite reliable by most standards, they are limited in repeating rate, average power, and reliability because the final stage of energy delivery is based on spark gap performance. In addition, they have a low duty factor of operation. To provide a higher burst rate and greater reliability, the researchers used new technology to develop a magnetic pulse compression scheme that eliminates all spark gaps and exceeds requirements. The paper describes the scheme. The magnetic drive system can be tailored to drive induction cells from a few kA to over 10 kA at 500 kV, with average beam power levels in the megawatts. This new 5-MeV, 2.5-kA LIA under construction at the Lawrence Livermore National Laboratory (LLNL) will be used for the development of high brightness sources and will provide a test bed for the new technology, which should lead to LIAs that surpass the radio frequency linacs for efficiency and reliability, as well as fit other industrial applications, such as sewage sterilization

  1. Irradiation creep under 60 MeV alpha irradiation

    International Nuclear Information System (INIS)

    Reiley, T.C.; Shannon, R.H.; Auble, R.L.

    1980-01-01

    Accelerator-produced charged-particle beams have advantages over neutron irradiation for studying radiation effects in materials, the primary advantage being the ability to control precisely the experimental conditions and improve the accuracy in measuring effects of the irradiation. An apparatus has recently been built at ORNL to exploit this advantage in studying irradiation creep. These experiments employ a beam of 60 MeV alpha particles from the Oak Ridge Isochronous Cyclotron (ORIC). The experimental approach and capabilities of the apparatus are described. The damage cross section, including events associated with inelastic scattering and nuclear reactions, is estimated. The amount of helium that is introduced during the experiments through inelastic processes and through backscattering is reported. Based on the damage rate, the damage processes and the helium-to-dpa ratio, the degree to which fast reactor and fusion reactor conditions may be simulated is discussed. Recent experimental results on the irradiation creep of type 316 stainless steel are presented, and are compared to light ion results obtained elsewhere. These results include the stress and temperature dependence of the formation rate under irradiation. The results are discussed in relation to various irradiation creep mechanisms and to damage microstructure as it evolves during these experiments. (orig.)

  2. Dipole response of 76Se above 4 MeV

    Science.gov (United States)

    Goddard, P. M.; Cooper, N.; Werner, V.; Rusev, G.; Stevenson, P. D.; Rios, A.; Bernards, C.; Chakraborty, A.; Crider, B. P.; Glorius, J.; Ilieva, R. S.; Kelley, J. H.; Kwan, E.; Peters, E. E.; Pietralla, N.; Raut, R.; Romig, C.; Savran, D.; Schnorrenberger, L.; Smith, M. K.; Sonnabend, K.; Tonchev, A. P.; Tornow, W.; Yates, S. W.

    2013-12-01

    The dipole response of 3476Se in the energy range from 4 to 9 MeV has been analyzed using a (γ⃗,γ') polarized photon scattering technique, performed at the High Intensity γ-Ray Source facility at Triangle Universities Nuclear Laboratory, to complement previous work performed using unpolarized photons. The results of this work offer both an enhanced sensitivity scan of the dipole response and an unambiguous determination of the parities of the observed J=1 states. The dipole response is found to be dominated by E1 excitations, and can reasonably be attributed to a pygmy dipole resonance. Evidence is presented to suggest that a significant amount of directly unobserved excitation strength is present in the region, due to unobserved branching transitions in the decays of resonantly excited states. The dipole response of the region is underestimated when considering only ground state decay branches. We investigate the electric dipole response theoretically, performing calculations in a three-dimensional (3D) Cartesian-basis time-dependent Skyrme-Hartree-Fock framework.

  3. Neutrons leaked from a 45 MeV linac facility

    Energy Technology Data Exchange (ETDEWEB)

    Kitaichi, Masatoshi; Sawamura, Sadashi; Yamada, Takuma; Sawamura, Teruko; Kaneko, Junnichi H. [Hokkaido Univ., Sapporo (Japan); Nojiri, Itiro [Japan Nuclear Cycle Development Institute, Ibaraki (Japan)

    2002-07-01

    Dose evaluation for skyshine from nuclear facilities is an issue in environmental evaluations. Therefore, benchmark data for skyshine and well-investigated codes for skyshine would be useful in the rational evaluations of nuclear facilities. The purpose of this study is to obtain benchmark data of skyshine and to investigate the effect of source spectra and angular distribution on the skyshine process. In this study spatial and time distributions of neutrons leaked from the Hokkaido University 45 MeV electron linac facility were measured and compared with calculations. Neutrons were emitted from the ( ,n) reaction produced by bremsstrahlung radiation in a lead target irradiated with electrons from the linac. The skyshine process of neutrons transported through the facility building to the outside was investigated. The source spectrum of the skyshine process was evaluated using a cylindrical multi-moderator spectrometer and unfolding code, the SAND-II, and the results were compared. Measurements were carried out to a distance of 330 m from the facility. The measured spatial dose distribution was found not to coincide with the calculations. The discrepancy is discussed based on an analysis of the spatial and time distributions, and the energy spectrum which suggests that the source spectrum and the angular distribution assumed in the calculation was not sufficiently similar to simulate the experimental situation. The time distribution introduced in this study appears to be useful in discussions of the skyshine process and its sources.

  4. Calculation of 14 MeV neutron transmission

    International Nuclear Information System (INIS)

    Vyrskij, M.Yu.; Dubinin, A.A.; Zhuravlev, V.I.; Isaev, N.V.; Klintsov, A.A.; Krivtsov, A.S.; Linge, I.I.; Panfilov, E.I.; Prit'mov, A.P.

    1979-01-01

    The possibility of using the 28 group constant system (28-GCS) for calculating the transport of neutrons with initial energy of 14 MeV in thermonuclear reactor blankets is studied. A blanket project suggested by the Oak Ridge National Laboratory is used as a test version to estimate applicability of the 28-GCS. Niobium is used in a blanket as a structural material. A mixture of lithium nuclides is used for tritium production. The results of blanket test calculation and the calculational results obtained using the 28-GCS from the UKNDL library are compared. The numerical 28-group calculation of blonket is carried out by means of the ROZ-6 and ROZ-9 codes but not by the Monte-Carlo method as compared with the test calculation. Time of the blanket calculation on the BESM-6 computer by means of the ROZ-9 code in 2P 5 approximation using the 28-GCS amounts to 10 min. It is noted that to create effective codes for the numerical blanket calculation different calculational grids are necessary for different energy grups. The calculations carried out have shown the possibility of using the 28-group library of cross sections for the numerical solution of the neutron transport equation in estimating analysis of blankets

  5. CESAR, 2 MeV electron storage ring; general view.

    CERN Multimedia

    CERN PhotoLab

    1964-01-01

    CESAR (CERN Electron Storage and Accumulation Ring) was built as a study-model for the ISR (Intersecting Storage Rings). The model had to be small (24 m circumference) and yet the particles had to be highly relativistic, which led to the choice of electrons. On the other hand, in order to model the behaviour of protons, effects from synchrotron radiation had to be negligible, which meant low magnetic fields (130 G in the bending magnets) and a corresponding low energy of 1.75 MeV. All the stacking (accumulation) procedures envisaged for the ISR were proven with CESAR, and critical aspects of transverse stability were explored. Very importantly, CESAR was the test-bed for the ultrahigh vacuum techniques and components, essential for the ISR, with a final pressure of 6E-11 Torr. The CESAR project was decided early in 1960, design was completed in 1961 and construction in 1963. After an experimental period from 1964 to 1967, CESAR was dismantled in 1968.

  6. CESAR, 2 MeV electron storage ring.

    CERN Multimedia

    CERN PhotoLab

    1967-01-01

    CESAR (CERN Electron Storage and Accumulation Ring) was built as a study-model for the ISR (Intersecting Storage Rings). The model had to be small (24 m circumference) and yet the particles had to be highly relativistic, which led to the choice of electrons. On the other hand, in order to model the behaviour of protons, effects from synchrotron radiation had to be negligible, which meant low magnetic fields (130 G in the bending magnets) and a corresponding low energy of 1.75 MeV. All the stacking (accumulation) procedures envisaged for the ISR were proven with CESAR, and critical aspects of transverse stability were explored. Very importantly, CESAR was the test-bed for the ultrahigh vacuum techniques and components, essential for the ISR, with a final pressure of 6E-11 Torr. The CESAR project was decided early in 1960, design was completed in 1961 and construction in 1963. After an experimental period from 1964 to 1967, CESAR was dismantled in 1968.

  7. 400 MeV upgrade for the Fermilab linac

    International Nuclear Information System (INIS)

    MacLachlan, J.A.

    1989-01-01

    Fermilab has plans for a comprehensive accelerator upgrade to open new possibilities for both the fixed target and collider experimental programs. An early step in this program is to increase the energy of the linac from 200 to 400 MeV by replacing the last four of its nine 201 MHz Alvarez tanks with twenty-eight 805 MHz side-coupled cavity chains operating at about 8 MV/m average axial field. The principal purpose is to reduce the incoherent spacecharge tuneshift at injection into the Booster which currently limits both the brightness of the beam, an important determinant of collider luminosity, and total intensity to produce both the antiprotons for the collider and the beams to fixed target experimental areas. Other consequences of higher Booster injection energy expected to contribute to some degree of higher intensity limits and improved operational characteristics include improved quality of the guide field at injection, reduced frequency swing for the rf systems, and smaller emittance for the injected beam. The linac upgrade project has moved from a 1986 study through a development project including structure models and numerical studies to a full-feature module prototyping starting this year

  8. Si exfoliation by MeV proton implantation

    International Nuclear Information System (INIS)

    Braley, Carole; Mazen, Frédéric; Tauzin, Aurélie; Rieutord, François; Deguet, Chrystel; Ntsoenzok, Esidor

    2012-01-01

    Proton implantation in silicon and subsequent annealing are widely used in the Smart Cut™ technology to transfer thin layers from a substrate to another. The low implantation energy range involved in this process is usually from a few ten to a few hundred of keV, which enables the separation of up to 2 μm thick layers. New applications in the fields of 3D integration and photovoltaic wafer manufacturing raise the demand for extending this technology to higher energy in order to separate thicker layer from a substrate. In this work, we propose to investigate the effect of proton implantation in single crystalline silicon in the 1–3 MeV range which corresponds to a 15–100 μm range for the hydrogen maximum concentration depth. We show that despites a considerably lower hydrogen concentration at R p , the layer separation is obtained with fluence close to the minimum fluence required for low energy implantation. It appears that the fracture propagation in Si and the resulting surface morphology is affected by the substrate orientation. Defects evolution is investigated with Fourier Transform Infrared Spectroscopy. The two orientations reveal similar type of defects but their evolution under annealing appears to be different.

  9. Heliospheric MeV energization due to resonant interaction

    International Nuclear Information System (INIS)

    Roth, Ilan

    2001-01-01

    The prompt enhancement of relativistic electron flux during active geomagnetic periods, and the impulsive increase in the flux of the heliospheric energetic heavy ions during active solar periods are of major importance with respect to the proper operation of electronics on space-borne spacecraft and the safety of interplanetary human travel, respectively. Both enhancements may be caused by resonant wave-particle interaction with oblique electromagnetic waves on the terrestrial and coronal field lines. Whistler waves, which are enhanced significantly during substorms and which propagate obliquely to the magnetic field, can interact with energetic electrons through Landau, cyclotron, and higher harmonic resonant interactions when the Doppler-shifted wave frequency equals any (positive or negative) integer multiple of the local relativistic gyrofrequency. This interaction occurs over a broad spatial region when a relativistic electron is bouncing in the terrestrial magnetic field. Coronal ions interact selectively with electromagnetic ion-cyclotron (emic) waves which are correlated with impulsive flares. This interaction occurs over a small spatial region when the Doppler-shifted frequency matches the first or higher harmonic of the ion gyrofrequency. Recent new observations of terrestrial MeV X-rays are interpreted as a resonant loss of the radiation belt electrons

  10. Emittance measurements in Grumman 1 MeV beamline

    International Nuclear Information System (INIS)

    Debiak, T.; Gammel, G.; Melnychuk, S.

    1992-01-01

    The emittance of a 30 keV H - beam has been measured with an Allison type electrostatic analyser at two positions separated by 85 cm along the Grumman 1 MeV beamline LEBT at low currents (about 4 mA, no Cs 2 O additive in the source) and at higher currents (10-15 mA, with Cs 2 O additive in the source). No emittance growth was observed between the two positions, but, at the higher current level, the emittance was about 60% higher than at the low current level (Σ n ,rms = .0045 π cm-mrad vs. 0070 π cm-mrad). Argon was then introduced up to a partial pressure of 4x10 -5 torr, and the emittance decreased back to a range corresponding to that found at the lower currents. However, beam noise was observed at the downstream position, and there is evidence for a small amount of emittance growth (<20%) between the two positions

  11. Performance of the 2 MeV microwave gun for the SSRL 150 MeV linac

    International Nuclear Information System (INIS)

    Borland, M.; Weaver, J.N.; Wiedemann, H.; Miller, R.H.; Tanabe, E.

    1990-09-01

    As described in a previous article, the preinjector linac for SSRL's 3 GeV synchrotron is fed by a 2 MeV, 1.5 A, low-emittance microwave gun, consisting of a thermionic cathode mounted in the first cell of a 1-1/2-cell S-band cavity. In this article, we report on the successful operation of the low-emittance gun, the longitudinally-bunching alpha-magnet, and the three-microbunch FET-pulsed beam-chopper. Simulations predict a normalized rms emittance at the gun exit of less than 10 π·m e c·μm; chromatic effects in transport optics increase this to approximately 30 π·m e c·μm. The gun was specifically designed to have a longitudinal phase-space suited to magnetic compression, as a result of which we predict that peak currents in excess of 300 A in a 1 ps bunch are feasible with the existing alpha-magnet. Results of simulations and experiments will be presented and compared. 13 refs., 9 figs

  12. Design and performance of a 3.3-MeV linear induction accelerator (LIA)

    International Nuclear Information System (INIS)

    Cheng Nianan; Zhang Shouyun; Tao Zucong

    1992-01-01

    A 3.3-MeV linear induction accelerator (LIA) has been designed and constructed at the China Academy of Engineering Physics. The parameters of 3.4 MeV, 2 kA, 80 ns and 1 x 10 4 A/(rad.cm) 2 have been achieved. It has been used for SG-1 FEL experiments. The accelerator is mounted on a movable frame so that , after moving 3 m transversely, it can be assembled with more modules into a 10-MeV LIA. The authors summarize the physics and engineering aspects of the LIA facility and describe the measuring means of characters for the beam

  13. High-resolution observation of phase contrast at 1MeV. Amorphous or crystalline objects

    International Nuclear Information System (INIS)

    Bourret, A.; Desseaux, J.

    1975-01-01

    Many authors have stressed the possibilities of high voltage to improve resolution, but owing to numerous experimental difficulties the resolution limit at 1MeV, which lies around 1A for conventional lenses, has so far been unattainable. Thus the phase contrast at 1MeV has not been studied on evaporated objects. On the other hand the fringes of crystal planes have been observed at 1MeV. the CEN-G microscope having been considerably modified it has been possible to observe the phase contrast of amorphous or crystalline objects [fr

  14. NSLS 3: Conceptual design report: 750 MeV e+ or e- injector

    International Nuclear Information System (INIS)

    1986-05-01

    The 750 MeV positron or electron injector is comprised of an electron linear accelerator which accelerates an intense beam of electrons to an energy of about 250 MeV, a positron converter, a second linear accelerator that boosts the final positron energy to 750 MeV, and a damping ring in which radiation damping is used to reduce the emittance of the positron beam for injection into the storage rings. The reasons for the need of a new injector are enumerated. The conceptual design of the system and its component systems are described, as well as project cost, schedule, and manpower requirements

  15. Experimental apparatus to determine lead attenuation coefficients for photons of 0.511 MeV

    International Nuclear Information System (INIS)

    Vargas, Luis C.B.; Cardoso, Domingos O.; Gavazza, Sérgio; Morales, Rudnei K.; Oliveira, Luciano S. R.

    2017-01-01

    Radioactive gamma-emitting sources with higher energies than 1.022 MeV, may interact with matter by pair production process, generating two photons of 0.511 MeV in the positron annihilation, that may contribute to increase doses in both IOE´s or public. National regulatory agencies require a radiation protection plan and a shielding project to consider the influence of these photons in the licensing procedure. This work will present all steps for the development of the experimental apparatus for determination of the attenuation coefficients for photons with energy of 0.511 MeV in lead. (author)

  16. Two body photodisintegration of the deuteron from 100 to 800 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, R.; Annand, J.R.M.; Anthony, I. [Glasgow Univ. (United Kingdom). Dept. of Physics and Astronomy; Ahrens, J.; Beck, R. [Mainz Univ. (Germany). Inst. fuer Kernphysik; Braghieri, A.; Pedroni, P. [Istituto Nazionale di Fisica Nucleare, Pavia (Italy); Altieri, S. [Istituto Nazionale di Fisica Nucleare, Pavia (Italy)]|[Pavia Univ. (Italy). Ist. di Fisica Nucleare; Audit, G.; D`Hose, N. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee] [and others

    1996-01-01

    The total and the differential cross sections for the D({gamma},p)n reaction have been measured over the photon energy range 100-800 MeV at the 855 MeV MAMI Microtron in Mainz. The data are presented in the form of thirty-five angular distributions at c.m. proton angles between 30 deg-160 deg in 10 deg intervals and at photon energies in steps of 20 MeV. Previous experimental work is reassessed in the light of the present results and the results compared with some recent theoretical calculations. (author). Submitted to Nuclear Physics, B (NL); 23 refs.

  17. Neutron scattering differential cross sections of carbon and bismuth at 37 MeV

    International Nuclear Information System (INIS)

    Zhou Zuying; Tang Hongqing; Qi Bujia; Zhou Chenwei; Du Yanfeng; Xia Haihong; Walter, R.L.; Tornow, W.; Howell, C.; Braun, R.; Roper, C.; Chen Zemin; Chen Zhengpeng; Chen Yingtang

    1997-01-01

    Elastic differential cross sections of 37 MeV neutrons scattered from carbon and bismuth were measured in the angular range 11 to 160 degrees by means of the multi-detector TOF facility. The 37 MeV neutrons were produced via the T(d,n) 4 He reaction in a tritium gas target. The pulsed 20 MeV deuteron beam was provided by the HI-13 tandem accelerator. The angular distribution of scattered neutrons from carbon and bismuth were measured in the angular range 11 degree to 145 degree and 11 degree to 160 degree respectively in steps of about 3 degree

  18. Nuclear size comparison of even titanium isotopes using 140-MeV α-particle scattering

    International Nuclear Information System (INIS)

    Roberson, P.L.; Goldberg, D.A.; Wall, N.S.; Woo, L.W.; Chen, H.L.

    1979-01-01

    Systematic variations in nuclear-matter distributions have been determined by analyzing the measured elastic scattering of 140-MeV alpha particles from /sup 46,48,50/Ti. The ''unique'' optical potentials obtained (J/sub R//4A approx. = 300 MeV fm 3 , J/sub I//4A approx. = 100 MeV fm 3 ) indicate that isotopic differences occur primarily in the strength of the imaginary potential. The rms matter radii increase with A, in contrast to those of the charge distributions. The matter-radius results are in agreement with Hartree-Fock calculations

  19. Two body photodisintegration of the deuteron from 100 to 800 MeV

    International Nuclear Information System (INIS)

    Crawford, R.; Annand, J.R.M.; Anthony, I.; Altieri, S.; Pavia Univ.; Audit, G.; D'Hose, N.

    1996-01-01

    The total and the differential cross sections for the D(γ,p)n reaction have been measured over the photon energy range 100-800 MeV at the 855 MeV MAMI Microtron in Mainz. The data are presented in the form of thirty-five angular distributions at c.m. proton angles between 30 deg-160 deg in 10 deg intervals and at photon energies in steps of 20 MeV. Previous experimental work is reassessed in the light of the present results and the results compared with some recent theoretical calculations. (author)

  20. Color centers of a borosilicate glass induced by 10 MeV proton, 1.85 MeV electron and 60Co-γ ray

    Science.gov (United States)

    Du, Jishi; Wu, Jiehua; Zhao, Lili; Song, Lixin

    2013-05-01

    Optical absorption spectra, electron paramagnetic resonance (EPR) spectra, Raman spectra of a borosilicate glass after irradiation by 10 MeV proton, 1.85 MeV electron and 60Co-γ ray were studied. The process of irradiation inducing color centers in the glass was discussed. The band gap of the glass before and after 60Co-γ ray irradiation was studied using Mott and Davis's theory, and it was found that calculated change of the band gap introduced a paradox, because Mott and Davis's theory on the band gap cannot be adopted in the study on the irradiated glass.

  1. Photon mass energy absorption coefficients from 0.4 MeV to 10 MeV for silicon, carbon, copper and sodium iodide

    International Nuclear Information System (INIS)

    Oz, H.; Gurler, O.; Gultekin, A.; Yalcin, S.; Gundogdu, O.

    2006-01-01

    The absorption coefficients have been widely used for problems and applications involving dose calculations. Direct measurements of the coefficients are difficult, and theoretical computations are usually employed. In this paper, analytical equations are presented for determining the mass energy absorption coefficients for gamma rays with an incident energy range between 0.4 MeV and 10 MeV in silicon, carbon, copper and sodium iodide. The mass energy absorption coefficients for gamma rays were calculated, and the results obtained were compared with the values reported in the literature.

  2. Photon mass energy absorption coefficients from 0.4 MeV to 10 MeV for silicon, carbon, copper and sodium iodide

    Energy Technology Data Exchange (ETDEWEB)

    Oz, H.; Gurler, O.; Gultekin, A. [Uludag University, Bursa (Turkmenistan); Yalcin, S. [Kastamonu University, Kastamonu (Turkmenistan); Gundogdu, O. [University of Surrey, Guildford (United Kingdom)

    2006-07-15

    The absorption coefficients have been widely used for problems and applications involving dose calculations. Direct measurements of the coefficients are difficult, and theoretical computations are usually employed. In this paper, analytical equations are presented for determining the mass energy absorption coefficients for gamma rays with an incident energy range between 0.4 MeV and 10 MeV in silicon, carbon, copper and sodium iodide. The mass energy absorption coefficients for gamma rays were calculated, and the results obtained were compared with the values reported in the literature.

  3. DC and RF ion accelerators for MeV energies

    International Nuclear Information System (INIS)

    Urbanus, W.H.

    1990-01-01

    This thesis deals with the transport and acceleration of intense ion beams in single-ended Van de Graaff accelerators and the multiple beam rf accelerator MEQALAC (Multiple Electrostatic Quadrupole Array Linear Accelerator). Ch. 2 discusses several beam-envelope calculation techniques and describes the ion-optical components of a 1 MV, high-current, heavy-ion implantation facility and a 2 MV facility for analyzing purposes. The X-ray level of these accelerators is kept low, such that no shielding is needed, by keeping the energy of the secondary electrons sufficiently low, which is accomplished by a suppression system of small permanent magnets built in the acceleration tubes (ch. 3). Ch.'s 4,5 and 6 cover various aspects of stage II of the MEQALAC project. This stage deals with the parallel acceleration of four high-current N + beams from 40 keV to 1 MeV. Acceleration takes place in 32 rf gaps which are part of a modified interdigital H-resonator. In between the accelerating gaps, small electrostatic quadrupoles are mounted, which oppose the space charge forces of the intense ion beams. The lenses are arranged in a periodic focusing structure. A bucket-type plasma ion source is used, which produces both N + and N 2 + ions. In between the ion source and the MEQALAC section, a Low Energy Beam Transport (LEBT) section is mounted which provides for the drift space for a buncher. The latter device transforms the extracted dc beams into bunched beams which are accepted by the MEQALAC section. In ch. 4 the transport of ion beams that contain both N + and N 2 + ions, so-called mixed beams, through the LEBT section is discussed and equations for the current limit of a mixed beam are derived. Bunching of mixed N + , N 2 + beams is discussed in ch. 5. Multichannel acceleration of N + ions with the MEQALAC is discussed in ch. 6. (author). 122 refs.; 67 figs.; 1 tab

  4. Negative pion-nucleus elastic scattering at 20 and 40 MeV

    International Nuclear Information System (INIS)

    Burleson, G.; Blanpied, G.; Cottingame, W.; Daw, G.; Park, B.; Seth, K.K.; Barlow, D.; Iversen, S.; Kaletka, M.; Nann, H.; Saha, A.; Smith, D.; Redwine, R.P.; Burger, W.; Farkhondeh, M.; Saghai, B.; Anderson, R.

    1994-01-01

    Differential cross sections for the elastic scattering of 20 and 40 MeV π - by nuclei ranging from 12 C to 208 Pb are reported. Comparisons are made with the predictions of the Michigan State University (MSU) optical potential

  5. Temperature and 8 MeV electron irradiation effects on GaAs solar cells

    Indian Academy of Sciences (India)

    1Department of Physics, Mangalore Institute of Technology and Engineering, ... strate were irradiated with 1 MeV electrons, they showed high radiation tolerance ... under both forward and reverse bias in the temperature range of 270–315 K ...

  6. Beam dynamics design of the 211 MeV APT normal conducting linac

    International Nuclear Information System (INIS)

    Young, L.M.; Billen, J.H.; Takeda, H.; Wood, R.L.

    1998-01-01

    This paper describes the normal conducting linac design that is part of the Accelerator for Production of Tritium (APT) project. The new version of PARMILA designed this linac. This linac accepts the beam from the 6.7 MeV radio frequency quadrupole without a separate matching section. At about 10 MeV, it has a smooth transition in the length of period from 8βλ to 9βλ in quadrupole focusing lattice. This adjustment of the period was needed to provide sufficient space for the quadrupole focusing magnets and beam diagnostic equipment. The linac consists of the coupled cavity drift tube linac up to 97 MeV and coupled cavity linac above 97 MeV

  7. A 1MeV, 1A negative ion accelerator test facility

    International Nuclear Information System (INIS)

    Hanada, M.; Dairaku, M.; Inoue, T.; Miyamoto, K.; Ohara, Y.; Okumura, Y.; Watanabe, K.; Yokoyama, K.

    1995-01-01

    For the Proof-of-Principle test of negative ion acceleration up to 1 MeV, the beam energy required for ITER, a negative ion test facility named MeV Test Facility (MTF) and an ion source/accelerator have been designed and constructed. They are designed to produce a 1 MeV H- beam at a low source pressure of 0.13Pa. The MTF has a power supply system, which constituts of a 1MV, 1A, 60 s Cockcroft-Walton type dc high energy generator and power supplies for negative ion generation and extraction (ion source power supplies). The negative ion source/accelerator is composed of a cesiated volume source and a 5-stage, multi-aperture, electrostatic accelerator. The MTF and the ion source/accelerator have been completed, and the accelertion test up to 1 MeV of the H- ions has started. (orig.)

  8. Neutron data library for transactinides at energies up to 100 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Korovin, Y.A.; Artisyuk, V.V.; Konobeyev, A.Y. [Obninsk Institute of Nuclear Power Engineering (Russian Federation)

    1995-10-01

    New neutron data library for transactinides is briefly described. The library includes evaluated cross-sections for fission and threshold neutron induced reactions for isotopes of U, Np and Pu at energies 0-100 MeV.

  9. Application of calorimeters for 5 MeV EB and bremsstrahlung dosimetry

    DEFF Research Database (Denmark)

    Sato, T.; Takahashi, T.; Saito, T.

    1993-01-01

    Graphite and water calorimeters, which were developed for use a 10 MeV electron beams (EB) at Riso National Laboratory, were used for process validation and routine dosimeter calibration at a 5 MeV EB. Water calorimeters were used for reference measurements for 5 MeV EB, the response was found...... to be directly proportional to the beam current and the variation among three water calorimeters was less than +/- 2 % in the range of 10 to 40 kGy. CTA, PMMA, RCD dosimeters were calibrated by irradiating the dosimeters and water calorimeters Simultaneously. The water calorimeter was proved to be an useful tool...... at 5 MeV EB. Graphite calorimeters gave reproducible readings within 3.3 % relative errors (95 % confidence level) for X-ray measurement....

  10. Search for diffusion of counter-passing MeV ions in the TFTR tokamak

    International Nuclear Information System (INIS)

    Zweben, S.J.; Boivin, R.; Chang, C.S.; Hammett, G.; Mynick, H.E.

    1991-07-01

    Confinement studies of MeV ions will play an important role in the research leading to burning plasmas in tokamaks, since any significant radial transport of MeV alpha particles will affect the heating rate or heating profiles of these plasmas. Because the energy, gyroradius, and collisionality of these MeV ions is very different from that of the background plasma, their transport rates cannot be assumed equal to those of the bulk plasma ions. Note that the desired confinement time for 3.5 MeV alphas is set by their thermalization time, which can be up to τ th,α ∼1 sec for the steady-state phase of ITER, requiring D 2 /sec. This is equivalent to over ∼100,000 alpha particle transits of the torus. 28 refs., 24 figs., 2 tabs

  11. Elastic scattering of 90 - 120 MeV 3He particles and unique optical potential

    International Nuclear Information System (INIS)

    Hyakutake, M.; Matoba, M.; Kumabe, I.; Fukada, M.; Komatuzaki, T.

    1978-01-01

    The elastic scattering of 109.2 MeV 3 He particles by 40 Ca, 58 Ni, 90 Zr and 116 Sn has been investigated over a wide angular range. The elastic scattering cross sections have been analyzed in terms of the optical model. The data for each nucleus studied were sufficient to eliminate the discrete ambiguity in the strength of the optical potential; the unique potential which fits the data has real well depth of about 100 MeV and a corresponding volume integral per nucleon pair of about 310 MeV fm 3 . The elastic scattering of 3 He particles by 58 Ni has been further measured at bombarding energies of 89.3 and 118.5 MeV, and the incident-energy dependence of the optical potential of 3 He particles for 58 Ni was obtained. (author)

  12. Measurements and amplitude analysis of small angle pp polarization between 398 and 572 MeV

    International Nuclear Information System (INIS)

    Aebischer, D.; Favier, B.; Greeniaus, L.G.; Hess, R.; Junod, A.; Lechanoine, C.; Nikles, J.C.; Rapin, D.; Werren, D.W.

    1976-01-01

    The analyzing power of pp scattering in the cm angular range 4 to 22 0 at 398 to 572 MeV. The analyzing power was determined from the asymmetry in the azimuthal angle distributions of the scattered protons

  13. The 600 MeV Saclay electron linac: 40000 hour operation

    International Nuclear Information System (INIS)

    Netter, F.

    1977-01-01

    After 40000 hours of operation, the 600 MeV Saclay's electron linac (ALS) does appear as an efficient and versatile tool, for high resolution work (20 μA in ΔE = 40 keV at E = 200MeV), for high power pion production (300 μA in 20 μs pulses at 1000 Hz and 400 MeV or 240 μA in 4 μs pulses at 3000 Hz and 390 MeV), for highly reliable positron beams acceleration, a.s.o. Main improvements made in the recent years are described in particular the automatic beam switching between any two ways among the beam handling system; and the computer newly installed in the control room with a powerful visual display allowing an easy and flexible dialogue of the operators with the computer [fr

  14. Application of calorimeters for 5 MeV EB and bremsstrahlung dosimetry

    International Nuclear Information System (INIS)

    Sato, Toshio; Takahashi, Toru; Saito, Toshio; Takehisa, Masaaki; Miller, A.

    1993-01-01

    Graphite and water calorimeters, which were developed for use with 10 MeV electron beams (EB) at Riso National Laboratory, were used for process validation and routine dosimeter calibration at a 5 MeV EB. Water calorimeters were used for reference measurements for 5 MeV EB, the response was found to be directly proportional to the beam current and the variation among three water calorimeters was less than ± 2% in the range of 10 to 40 kGy. CTA PMMA RCD dosimeters were calibrated by irradiating the dosimeters and water calorimeters simultaneously. The water calorimeter was proved to be an useful tool at 5 MeV EB. Graphite calorimeters gave reproducible readings within 3.3 % relative errors (95% confidence level) for X-ray measurement. (Author)

  15. Three-dimensional simulation studies of 10 MeV, 352.2 MHz drift ...

    Indian Academy of Sciences (India)

    It is proposed to build a drift tube Linac (DTL) at Raja Ramanna Centre for Advanced Technology, Indore, India, that will form a part of the future Spallation Neutron Source. This DTL will accelerate 30 mA H-ion beam from 3 MeV to 10 MeV. The DTL is designed to operate at 352.2 MHz with a maximum duty cycle of 3%.

  16. The drive system of 100 MeV electron linear accelerator

    International Nuclear Information System (INIS)

    Sun Yuzhen; Su Guoping; Wang Xiulong; Tianlu

    1988-06-01

    The principle, structure, measurement results and technical performances of microwave drive system for 100MeV electron linear accelerator are presented. In this system the peak power of 15 kW is produced by the S bank middle power klystron. The output power of the klystron is divided into six subdrive lines that drive six high power klystrons respectively. The results show the system with simple structure and good characteristics completely meets the requirements of 100 MeV Linac

  17. A 6.13MeV gamma reference source, measurement of the emission rate

    International Nuclear Information System (INIS)

    Robert, Andre; Blondel, Maurice; Morel, Jean; Thomas, Claude.

    1977-08-01

    A 6.13MeV γ reference source has been produced by using 13 C(α, nγ) 16 O reaction occurring in an intimate 13 C and 238 Pu mixture. With two walls made leak proof this standard source is easy handled and convenient to the calibration of detectors. The 6.13MeV gamma ray is emitted without Doeppler effect, is measured with an uncertainty of 6% by three independent methods [fr

  18. A technique for determining electron losses for a 20 MeV microtron

    International Nuclear Information System (INIS)

    Harisha, P.; Nayak, A.R.; Mehta, S.K.; Soni, H.C.; Siddappa, K.

    1999-01-01

    A 22 orbit, 20 MeV electron microtron is used as a preaccelerator for the 700 MeV booster synchrotron at INDUS-1, CAT, Indore. Estimation of electron losses at the RF cavity from each orbit is important in obtaining the radiation doses from the body of the microtron. Radiation mapping of the microtron can be used to estimate these loss terms as an alternate to actual measurement by using a measuring probe. (author)

  19. Coulomb dissociation of {sup 8}B at 254 A MeV

    Energy Technology Data Exchange (ETDEWEB)

    Suemmerer, K; Boue, F; Baumann, T; Geissel, H; Hellstroem, M; Koczon, P; Schwab, E; Schwab, W; Senger, P; Surowiecz, A [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); Iwasa, N; Ozawa, A [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); [RIKEN Institute of Physical and Chemical Research, Saitama (Japan); Surowka, G [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); [Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Blank, B; Czajkowski, S; Marchand, C; Pravikoff, M S [Centre d` Etudes Nucleaires de Bordeaux-Gradignan, 33 (France); Foerster, A; Lauer, F; Oeschler, H; Speer, J; Sturm, C; Uhlig, F; Wagner, A [Technische Univ. Darmstadt (Germany); Gai, M [Connecticut Univ., Storrs, CT (United States). Dept. of Physics; Grosse, E [Inst. fuer Kern- und Hadronenphysik, Forschungszentrum Rossendorf, Dresden (Germany); Kohlmeyer, B [Philipps Univ., Marburg (Germany). Fachbereich Physik; Kulessa, R; Walus, W [Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Motobayashi, T [Rikkyo Univ., Tokyo (Japan). Dept. of Physics; Teranishi, T [RIKEN Institute of Physical and Chemical Research, Saitama (Japan)

    1998-06-01

    As an alternative method for determining the astrophysical S-factor for the {sup 7}Be(p,{gamma}){sup 8}B reaction we have measured the Coulomb dissociation of {sup 8}B at 254 A MeV. From our preliminary results, we obtain good agreement with both the accepted direct-reaction measurements and the low-energy Coulomb dissociation study of Iwasa et al. performed at about 50 A MeV. (orig.)

  20. Pb(n,2n) cross section at 14.1 MeV

    International Nuclear Information System (INIS)

    Zhou Delin

    1991-01-01

    Pb is a potential candidate for the neutron multiplier of the fusion reactor, so its (n, 2n) cross section at 14 MeV is of importance. This work is carried out to get a new evaluation of Pb (n,2n) cross section at 14.1 MeV for checking the angle-integrated neutron emission cross section. The equal weight averaged value 2252 +- 40 Mb is adopted in the evaluation

  1. Secondary neutron double differential cross sections from 209Bi at 14.2 MeV

    International Nuclear Information System (INIS)

    Shen Guanren; Xia Haihong; Tang Hongqing

    1992-01-01

    The secondary neutron double differential cross sections from 209 Bi at 14.2 MeV have been measured at 6 angles between 25 degree-150 degree using an associated particle TOF spectrometer. Flight path was 2.7 m. The neutron detector was biased at 1.3 MeV. The time resolution was about 1.2 ns. The data were compared with existing data and theoretical calculated results. Good agreement is achieved

  2. High energy resolution characteristics on 14MeV neutron spectrometer for fusion experimental reactor

    Energy Technology Data Exchange (ETDEWEB)

    Iguchi, Tetsuo [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.; Takada, Eiji; Nakazawa, Masaharu

    1996-10-01

    A 14MeV neutron spectrometer suitable for an ITER-like fusion experimental reactor is now under development on the basis of a recoil proton counter telescope principle in oblique scattering geometry. To verify its high energy resolution characteristics, preliminary experiments are made for a prototypical detector system. The comparison results show reasonably good agreement and demonstrate the possibility of energy resolution of 2.5% in full width at half maximum for 14MeV neutron spectrometry. (author)

  3. Absence of large M1 excitations in 208Pb below 8.4 MeV

    International Nuclear Information System (INIS)

    Holt, R.J.; Jackson, H.E.; Laszewski, R.M.; Specht, J.R.

    1979-01-01

    A very high-resolution measurement of the 208 Pb(γ-n 0 ) 207 Pb reaction was performed by use of the unique picopulse and the newly-installed neutron flight paths at the ANL electron linac facility. The 7.99-MeV resonance (E/sub n/ = 610 keV) exhibited a level-level interference pattern with the 7.98-MeV, E1 resonance in 208 Pb. 1 figure

  4. Anisotropic deformation of metallo-dielectric core-shell colloids under MeV ion irradiation

    International Nuclear Information System (INIS)

    Penninkhof, J.J.; Dillen, T. van; Roorda, S.; Graf, C.; Blaaderen, A. van; Vredenberg, A.M.; Polman, A.

    2006-01-01

    We have studied the deformation of metallo-dielectric core-shell colloids under 4 MeV Xe, 6 and 16 MeV Au, 30 MeV Si and 30 MeV Cu ion irradiation. Colloids of silica surrounded by a gold shell, with a typical diameter of 400 nm, show anisotropic plastic deformation under MeV ion irradiation, with the metal flowing conform the anisotropically deforming silica core. The 20 nm thick metal shell imposes a mechanical constraint on the deforming silica core, reducing the net deformation strain rate compared to that of pure silica. In colloids consisting of a Au core and a silica shell, the silica expands perpendicular to the ion beam, while the metal core shows a large elongation along the ion beam direction, provided the silica shell is thick enough (>40 nm). A minimum electronic energy loss of 3.3 keV/nm is required for shape transformation of the metal core. Silver cores embedded in a silica shell show no elongation, but rather disintegrate. Also in planar SiO 2 films, Au and Ag colloids show entirely different behavior under MeV irradiation. We conclude that the deformation model of core-shell colloids must include ion-induced particle disintegration in combination with thermodynamical effects, possibly in combination with mechanical effects driven by stresses around the ion tracks

  5. Anisotropic deformation of metallo-dielectric core shell colloids under MeV ion irradiation

    Science.gov (United States)

    Penninkhof, J. J.; van Dillen, T.; Roorda, S.; Graf, C.; van Blaaderen, A.; Vredenberg, A. M.; Polman, A.

    2006-01-01

    We have studied the deformation of metallo-dielectric core-shell colloids under 4 MeV Xe, 6 and 16 MeV Au, 30 MeV Si and 30 MeV Cu ion irradiation. Colloids of silica surrounded by a gold shell, with a typical diameter of 400 nm, show anisotropic plastic deformation under MeV ion irradiation, with the metal flowing conform the anisotropically deforming silica core. The 20 nm thick metal shell imposes a mechanical constraint on the deforming silica core, reducing the net deformation strain rate compared to that of pure silica. In colloids consisting of a Au core and a silica shell, the silica expands perpendicular to the ion beam, while the metal core shows a large elongation along the ion beam direction, provided the silica shell is thick enough (>40 nm). A minimum electronic energy loss of 3.3 keV/nm is required for shape transformation of the metal core. Silver cores embedded in a silica shell show no elongation, but rather disintegrate. Also in planar SiO2 films, Au and Ag colloids show entirely different behavior under MeV irradiation. We conclude that the deformation model of core-shell colloids must include ion-induced particle disintegration in combination with thermodynamical effects, possibly in combination with mechanical effects driven by stresses around the ion tracks.

  6. Neutron-induced fission of uranium isotopes up to 100 MeV

    International Nuclear Information System (INIS)

    Lestone, J.P.; Gavron, A.

    1994-01-01

    The statistical-model description of the neutron-induced fission of U isotopes has been developed using densities of intrinsic states and spin cutoff parameters obtained directly from appropriate Nilsson model single-particle levels. The first-chance fission cross sections are reproduced well when the rotational contributions to the nuclear level densities are taken into account. In order to fit the U(n,f) cross sections above the threshold of second-chance fission, we must: (1) assume that the triaxial level-density enhancement is washed out at an excitation energy of approximately 7 MeV above the triaxial barriers with a width of approximately 1 MeV, implying a γ deformation for the first barriers where 10<γ<20 degree, and (2) include preequilibrium particle emission in the calculations. Above an incoming-neutron kinetic energy of approximately 17 MeV, our statistical model U(n,f) of cross sections increasingly overestimates the experimental data. This is not surprising since, at these high energies, little data exist on the scattering of neutrons to help guide the choice of optical-model parameters. A satisfactory reproduction of all of the available U(n,f) cross sections above 17 MeV is obtained by scaling our calculated compound-nucleus formation cross sections. This scaling factor falls from 1.0 at 17 MeV to 0.82 at 100 MeV

  7. Measurement of neutron yield by 62 MeV proton beam on a thick beryllium target

    Energy Technology Data Exchange (ETDEWEB)

    Osipenko, M., E-mail: osipenko@ge.infn.it [INFN, sezione di Genova, 16146 Genova (Italy); Ripani, M. [INFN, sezione di Genova, 16146 Genova (Italy); Alba, R. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Ricco, G. [INFN, sezione di Genova, 16146 Genova (Italy); Schillaci, M. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Barbagallo, M. [INFN, sezione di Bari, 70126 Bari (Italy); Boccaccio, P. [INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Celentano, A. [Dipartimento di Fisica dell' Università di Genova, 16146 Genova (Italy); Colonna, N. [INFN, sezione di Bari, 70126 Bari (Italy); Cosentino, L.; Del Zoppo, A.; Di Pietro, A. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Esposito, J. [INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Figuera, P.; Finocchiaro, P. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Kostyukov, A. [Moscow State University, Moscow 119992 (Russian Federation); Maiolino, C.; Santonocito, D.; Scuderi, V. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Viberti, C.M. [Dipartimento di Fisica dell' Università di Genova, 16146 Genova (Italy)

    2013-09-21

    The design of a low-power prototype of neutron amplifier recently proposed within the INFN-E project indicated the need for more accurate data on the neutron yield produced by a proton beam with energy of about 70 MeV impinging on a thick beryllium target. Such measurement was performed at the LNS superconducting cyclotron, covering a wide angular range from 0° to 150° and a complete neutron energy interval from thermal to beam energy. Neutrons with energy above 0.5 MeV were measured by liquid scintillators exploiting their time of flight to determine the kinetic energy. For lower energy neutrons, down to thermal energy, a {sup 3}He detector was used. The obtained data are in good agreement with previous measurements at 0° using 66 MeV proton beam, covering neutron energies >10MeV, as well as with measurements at few selected angles using protons of 46, 55 and 113 MeV energy. The present results extend the neutron yield data in the 60–70 MeV beam energy range. A comparison of measured yields to MCNP, FLUKA and Geant4 Monte Carlo simulations was performed.

  8. Measurement of (n,Xn) reaction cross sections at 96 MeV; Measure des sections efficaces (n,Xn) a 96 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Sagrado Garcia, Melle Inmaculada C. [Ecole Doctorale: SINEM, U.F.R. de Sciences, Universite de Caen/Basse-Normandie, Esplanade Paix14000 Caen (France)

    2006-10-15

    Nucleon induced reactions in the 20-200 MeV energy range are intensively studied since a long time. The evaporation and the pre-equilibrium processes correspond to an important contribution of the production cross section in these reactions. Several theoretical approaches have been proposed and their predictions must be tested. The experimental results shown in this work are the only complete set of data for the (n,Xn) reactions in this energy range. Neutron double differential cross section measurements using lead and iron targets for an incident neutron beam at 96 MeV were carried out at TSL Laboratory in Uppsala, Sweden. The measurements have been performed for the first time with an energy threshold of 2 MeV and for a wide angular range (15 angle - 98 angle). Neutrons have been detected using two independent setups, DECOI and DEMON and CLODIA and SCANDAL, in order to cover the whole energy range (2-100) MeV. The angular distributions, the differential cross sections and the total inelastic production cross sections have been calculated using the double differential cross sections. The comparison between the experimental data and the predictions given by two of the most popular simulation codes, GEANT3 and MCNPX, have been performed, as well as the comparison with the predictions of the microscopic simulation model DYWAN, selected for its treatment of nucleon-nucleon reactions. (author)

  9. Thermoluminescence response of Ge-, Al- and Nd- doped optical fibers by 6 MeV - electron and 6 MeV - photon irradiations

    International Nuclear Information System (INIS)

    Hossain, I.; Moburak, A. A.; Saeed, M.A.; Wagiran, H.; Hida, N.; Yaakob, H.N.

    2015-01-01

    In this paper, we report the prediction of thermoluminescence responses of Neodymium-doped SiO 2 optical fibre with various dose ranges from 0.5 Gy to 4.0 Gy by 6 MeV - electron irradiations without requirement for experimental measurements. A technique has been developed to calculate prediction of 6 MeV - electron response of Neodymium-doped SiO 2 optical fibre by observing the measured TL response of 6 MV - photon and the ratio of known measured photon/electron yield ratio distribution for Ge-doped, Al-doped optical fibre and standard TLD 100 dosimeter. The samples were kept in gelatin capsule an irradiated with 6 MV - photon at the dose range from 0.5 Gy to 4.0 Gy. Siemens model Primus 3368 linear accelerator located at Hospital Sultan Ismail, Johor Bahru has been used to deliver the photon beam to the samples. We found the average response ratio of 6 MV - photon and 6 MeV - electron in Ge-doped, Al-doped optical fibre and standard TLD-100 dosimeter are 0.83(3). Observing the measured value of 6 MV - photon irradiation this average ratio is useful to find the prediction of thermoluminescence responses by 6 MeV - electron irradiation of Neodymium-doped SiO 2 optical fibre by the requirement for experimental measurements with various dose ranges from 0.5 Gy to 4.0 Gy by 6 MV - photon irradiations.

  10. Study of the thermal oxidation of titanium and zirconium under argon ion irradiation in the low MeV range (E = 15 MeV)

    International Nuclear Information System (INIS)

    Do, N.-L.

    2012-01-01

    We have shown that argon ion irradiation between 1 and 15 MeV produces damage on both titanium and zirconium surfaces, taking the form of accelerated oxidation and/or craterization effects, varying as a function of the projectile energy and the annealing atmosphere (temperature and pressure) simulating the environmental conditions of the fuel/cladding interface of PWR fuel rods. Using AFM, we have shown that the titanium and zirconium surface is attacked under light argon ion bombardment at high temperature (up to 500 C) in weakly oxidizing medium (under rarefied dry air pressure ranging from 5,7 10 -5 Pa to 5 10 -3 Pa) for a fixed fluence of about 5 10 14 ions.cm -2 . We observed the formation of nano-metric craters over the whole titanium surface irradiated between 2 and 9 MeV and the whole zirconium surface irradiated at 4 MeV, the characteristics of which vary depending on the temperature and the pressure. In the case of the Ar/Ti couple, the superficial damage efficiency increases when the projectile energy decreases from 9 to 2 MeV. Moreover, whereas the titanium surface seems to be transparent under the 15-MeV ion beam, the zirconium surface exhibits numerous micrometric craters surrounded by a wide halo. The crater characteristics (size and superficial density) differ significantly from that observed both in the low energy range (keV) where the energy losses are controlled by ballistic collisions (Sn) and in the high energy range (MeV - GeV) where the energy losses are controlled by electronic excitations (Se), which was not completely unexpected in this intermediate energy range for which combined Sn - Se stopping power effects are possibly foreseen. Using XPS associated to ionic sputtering, we have shown that there is an irradiation effect on thermal oxidation of titanium, enhanced under the argon ion beam between 2 and 9 MeV, and that there is also an energy effect on the oxide thickness and stoichiometry. The study conducted using Spectroscopic

  11. Elastic scattering by lead and tin of γ-rays of 1.33 MeV and 1.17 MeV from 60Co, and of 1.12 MeV from 65Zn

    International Nuclear Information System (INIS)

    Hara, E.; Banaigs, J.; Eberhard, P.; Goldzahl, L.; Mey, J.

    1959-01-01

    Total elastic scattering is measured for 1.12, 1.17 and 1.33 MeV γ-rays and compared with new theoretical calculations. No effect of Delbrueck scattering is found, but an inelastic scattering appears, which we had neglected until now. Reprint of a paper published in 'Le journal de physique et le radium', tome 19, No. 7, July 1958, p. 668-673 [fr

  12. Measures of gamma rays between 0,3 MeV and 3,0 MeV and of the 0,511 MeV annihilation line coming from Galactic Center Region

    International Nuclear Information System (INIS)

    Jardim, M.V.A.

    1982-04-01

    The detection of the flux of the electron-positron annihilation line coming from the Galactic Center direction allows one to estimate the rate of positrons production and the corresponding luminosity. The results of measurements of the annihilation line flux intensity at 0.511 MeV, obtained with a balloon borne experiment to measure gamma rays in the energy interval 0.3 to 3 MeV are presented. The detector looked at the galactic disk in the longitude interval -31 0 0 and observed a flux intensity of (6.70 +- 0.85) x 10 -3 photons cm -2 s -1 , which is in good agreement with the flux value estimated assuming that the Galactic Center is a line source emitting uniformly. Some likely sources of positrons and annhilation regions are also discussed. The results for the continuum spectrum emitted from the Galactic Center in the energy interval 0.3 to 0.67 MeV are presented and compared with measurements had already made. (Author) [pt

  13. Conceptual design of 30 MeV magnet system used for BNCT epithermal neutron source

    International Nuclear Information System (INIS)

    Slamet Santosa; Taufik

    2015-01-01

    Conceptual design of 30 MeV Magnet System Used for BNCT Epithermal Neutron Source has been done based on methods of empirical model of basic equation, experiences of 13 MeV cyclotron magnet design and personal communications. In the field of health, cyclotron can be used as an epithermal neutron source for Boron Neutron Capture Therapy (BNCT). The development of cyclotron producing epithermal neutrons for BNCT has been performed at Kyoto University, of which it produces a proton beam current of 1.1 mA with energy of 30 MeV. With some experiences on 13 MeV cyclotron magnet design, to support BNCT research and development we performed the design studies of 30 MeV cyclotron magnet system, which is one of the main components of the cyclotron for deflecting proton beam into circular trajectory and serves as beam focusing. Results of this study are expected to define the parameters of particular cyclotron magnet. The scope of this study includes the study of the parameters component of the 30 MeV cyclotron and magnet initial parameters. The empirical method of basic equation model is then corroborated by a simulation using Superfish software. Based on the results, a 30 MeV cyclotron magnet for BNCT neutron source enables to be realized with the parameters of B 0 = 1.06 T, frequency RF = 64.733938 ≈ 65 MHz, the external radius of 0.73 m, the radius of the polar = 0.85 m, BH = 1.95 T and a gap hill of 4 cm. Because proton beam current that be needed for BNCT application is very large, then in the calculation it is chosen a great focusing axial νz = 0.630361 which can generate B V = 0.44 T. (author)

  14. Upper limit on the inner radiation belt MeV electron intensity

    Science.gov (United States)

    Li, X; Selesnick, RS; Baker, DN; Jaynes, AN; Kanekal, SG; Schiller, Q; Blum, L; Fennell, J; Blake, JB

    2015-01-01

    No instruments in the inner radiation belt are immune from the unforgiving penetration of the highly energetic protons (tens of MeV to GeV). The inner belt proton flux level, however, is relatively stable; thus, for any given instrument, the proton contamination often leads to a certain background noise. Measurements from the Relativistic Electron and Proton Telescope integrated little experiment on board Colorado Student Space Weather Experiment CubeSat, in a low Earth orbit, clearly demonstrate that there exist sub-MeV electrons in the inner belt because their flux level is orders of magnitude higher than the background, while higher-energy electron (>1.6 MeV) measurements cannot be distinguished from the background. Detailed analysis of high-quality measurements from the Relativistic Electron and Proton Telescope on board Van Allen Probes, in a geo-transfer-like orbit, provides, for the first time, quantified upper limits on MeV electron fluxes in various energy ranges in the inner belt. These upper limits are rather different from flux levels in the AE8 and AE9 models, which were developed based on older data sources. For 1.7, 2.5, and 3.3 MeV electrons, the upper limits are about 1 order of magnitude lower than predicted model fluxes. The implication of this difference is profound in that unless there are extreme solar wind conditions, which have not happened yet since the launch of Van Allen Probes, significant enhancements of MeV electrons do not occur in the inner belt even though such enhancements are commonly seen in the outer belt. Key Points Quantified upper limit of MeV electrons in the inner belt Actual MeV electron intensity likely much lower than the upper limit More detailed understanding of relativistic electrons in the magnetosphere PMID:26167446

  15. Shielding calculations for industrial 5/7.5MeV electron accelerators using the MCNP Monte Carlo Code

    Science.gov (United States)

    Peri, Eyal; Orion, Itzhak

    2017-09-01

    High energy X-rays from accelerators are used to irradiate food ingredients to prevent growth and development of unwanted biological organisms in food, and by that extend the shelf life of the products. The production of X-rays is done by accelerating 5 MeV electrons and bombarding them into a heavy target (high Z). Since 2004, the FDA has approved using 7.5 MeV energy, providing higher production rates with lower treatments costs. In this study we calculated all the essential data needed for a straightforward concrete shielding design of typical food accelerator rooms. The following evaluation is done using the MCNP Monte Carlo code system: (1) Angular dependence (0-180°) of photon dose rate for 5 MeV and 7.5 MeV electron beams bombarding iron, aluminum, gold, tantalum, and tungsten targets. (2) Angular dependence (0-180°) spectral distribution simulations of bremsstrahlung for gold, tantalum, and tungsten bombarded by 5 MeV and 7.5 MeV electron beams. (3) Concrete attenuation calculations in several photon emission angles for the 5 MeV and 7.5 MeV electron beams bombarding a tantalum target. Based on the simulation, we calculated the expected increase in dose rate for facilities intending to increase the energy from 5 MeV to 7.5 MeV, and the concrete width needed to be added in order to keep the existing dose rate unchanged.

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

    Science.gov (United States)

    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

  17. Elastic Neutron Scattering at 96 MeV from {sup 12}C and {sup 208}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Klug, J.; Blomgren, J.; Atac, A. [and others

    2003-04-01

    A facility for detection of scattered neutrons in the energy interval 50-130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20-180 MeV neutron beam line of the The Svedberg Laboratory, Uppsala. Elastic neutron scattering from {sup 12}C and {sup 208}Pb has been studied at 96 MeV in the 10-70 deg interval. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated uncertainty, 3 %, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions, based on phenomenology or microscopic nuclear theory.

  18. Low temperature irradiation of iron, zirconium and copper by 10 to 16 MeV protons

    Energy Technology Data Exchange (ETDEWEB)

    Omar, A M

    1978-01-01

    A theoretical analysis of scattering and radiation damage parameters is carried out for 14 MeV neutrons and 10-17 MeV protons on Fe, Ni, Cu, Zr, Nb, and Au. Damage energies are computed for the interactions using both elastic and non-elastic data. The results show that proton encounters deposit a greater damage energy than 14 MeV neutrons. To examine the theoretical results, electrical resistivity measurements are undertaken for Fe, Zr and Cu irradiated at 12 to 17.5K with 10 to 16 MeV protons. Post-irradiation annealing is carried out in situ using a closed-cycle helium-cooled cryostat. Values of the resistivity damage rate are compared with values estimated from the theoretical damage-energy results. Also, the observed stage I recovery is analysed in terms of the corresponding recovery reported for electron and fast-neutron irradiations. The relation between the 16 MeV proton data and published data estimated from a fusion reactor spectrum is discussed. It is also shown that protons create a damage structure similar to a superposition of the damage structures generated by electrons and fast neutrons. The sample state of imperfection is shown to influence the induced damage state in proton irradiation.

  19. Neutron total and scattering cross sections of 6Li in the few MeV region

    International Nuclear Information System (INIS)

    Smith, A.; Guenther, P.; Whalen, J.

    1980-02-01

    Neutron total cross sections of 6 Li are measured from approx. 0.5 to approx. 4.8 MeV at intervals of approx. 10 scattering angles and at incident-neutron intervals of approx.< 100 keV. Neutron differential inelastic-scattering cross sections are measured in the incident-energy range 3.5 to 4.0 MeV. The experimental results are extended to lower energies using measured neutron total cross sections recently reported elsewhere by the authors. The composite experimental data (total cross sections from 0.1 to 4.8 MeV and scattering cross sections from 0.22 to 4.0 MeV) are interpreted in terms of a simple two-level R-matrix model which describes the observed cross sections and implies the reaction cross section in unobserved channels; notably the (n;α)t reaction (Q = 4.783 MeV). The experimental and calculational results are compared with previously reported results as summarized in the ENDF/B-V evaluated nuclear data file

  20. 7.5 MeV High Average Power Linear Accelerator System for Food Irradiation Applications

    International Nuclear Information System (INIS)

    Eichenberger, Carl; Palmer, Dennis; Wong, Sik-Lam; Robison, Greg; Miller, Bruce; Shimer, Daniel

    2005-09-01

    In December 2004 the US Food and Drug Administration (FDA) approved the use of 7.5 MeV X-rays for irradiation of food products. The increased efficiency for treatment at 7.5 MeV (versus the previous maximum allowable X-ray energy of 5 MeV) will have a significant impact on processing rates and, therefore, reduce the per-package cost of irradiation using X-rays. Titan Pulse Sciences Division is developing a new food irradiation system based on this ruling. The irradiation system incorporates a 7.5 MeV electron linear accelerator (linac) that is capable of 100 kW average power. A tantalum converter is positioned close to the exit window of the scan horn. The linac is an RF standing waveguide structure based on a 5 MeV accelerator that is used for X-ray processing of food products. The linac is powered by a 1300 MHz (L-Band) klystron tube. The electrical drive for the klystron is a solid state modulator that uses inductive energy store and solid-state opening switches. The system is designed to operate 7000 hours per year. Keywords: Rf Accelerator, Solid state modulator, X-ray processing

  1. γ rays of 0.3-30 MeV from PSR0833 - 45

    International Nuclear Information System (INIS)

    Tuemer, O.T.; Long, J.; O'Neill, T.; Zych, A.; White, R.S.

    1984-01-01

    Pulsed γ rays from the Vela pulsar PSR0833-45 are reported for the first time at the medium energies, E, of 0.3-30 MeV. They were observed with the double scatter γ-ray telescope 31 days after a large glitch in the pulsar period. The first and second pulses were detected from single scatters in the top scintillators, S1, at energies > 0.3 MeV, and by double scatters from all detector cell pairs at energies of 1-30 MeV. The phase separation of the two pulses is 0.43 +- 0.02 at the same absolute phases previously found by SAS 2 and COS B for E > 35 MeV. The energy distribution with six points from 0.3 to 30 MeV appears to bend away from the COS B power law at the lower energies and is well below the HEAO 1 upper limits. (author)

  2. 29Si(d,3He)28Al reaction at 29 MeV

    International Nuclear Information System (INIS)

    Vernotte, J.; Berrier-Ronsin, G.; Fortier, S.; Hourani, E.; Kalifa, J.; Khendriche, A.; Maison, J.M.; Rosier, L.H.; Rotbard, G.

    1994-01-01

    The 29 Si(d, 3 He) 28 Al reaction has been investigated at 29 MeV incident energy. Observations using a split-pole magnetic spectrograph have been made of 55 levels of 28 Al in the range of excitation energy between 0 and 6.7 MeV. Most of them have been identified with 28 Al levels which have been previously observed by other techniques. The spectroscopic factors have been obtained for 23 of these levels through distorted-wave Born approximation analyses of measured angular distributions. The levels at E x =3.105 and 3.762 MeV have been definitely assigned J π =1 + and 0 + , respectively. Four levels which are populated through the pickup of a l p =1 proton have been observed at E x =4.998, 5.406, 6.021, and 6.652 MeV. The excitation energies and spectroscopic factors for positive-parity states were compared with the results of a recent, complete sd-shell space, shell-model calculation. This comparison led to the identification of 21 shell-model levels with experimental levels. This comparison seems accurate enough to make very likely the J π =3 + assignment for the levels at E x =2.988 and 4.597 MeV which were previously assigned J π =(1,3) +

  3. Depth distribution of damage in copper irradiated with MeV, Ni and He ions

    International Nuclear Information System (INIS)

    Narayan, J.; Noggle, T.S.; Oen, O.S.

    1975-01-01

    Transmission electron microscopy was used to study radiation damage as a function of depth caused by 58 and 4-MeV 58 Ni and 1-MeV He ions in copper single crystals at ambient temperature. The experimental damage density vs penetration depth distributions were compared with calculations based on the atomic collision theory of Lindhard et al. (LSS). For 58-MeV Ni ions, the calculated damage profile using the theoretical LSS value of the electronic stopping parameter (k = 0.167) agrees well with experiment. However, for 4-MeV Ni ions it is necessary to use k = 0.12 to get agreement with the experimental data. In the case of 1-MeV He, the depth location of the calculated damage peak is in good agreement with experiment when the electronic stopping determined by Chu and Powers is used whereas it is about 15 percent too close to the surface using the tables of Northcliffe and Schilling. (auth)

  4. Highly Stripped Ion Sources for MeV Ion Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, Ady

    2009-06-30

    Original technical objectives of CRADA number PVI C-03-09 between BNL and Poole Ventura, Inc. (PVI) were to develop an intense, high charge state, ion source for MeV ion implanters. Present day high-energy ion implanters utilize low charge state (usually single charge) ion sources in combination with rf accelerators. Usually, a MV LINAC is used for acceleration of a few rnA. It is desirable to have instead an intense, high charge state ion source on a relatively low energy platform (de acceleration) to generate high-energy ion beams for implantation. This de acceleration of ions will be far more efficient (in energy utilization). The resultant implanter will be smaller in size. It will generate higher quality ion beams (with lower emittance) for fabrication of superior semiconductor products. In addition to energy and cost savings, the implanter will operate at a lower level of health risks associated with ion implantation. An additional aim of the project was to producing a product that can lead to long­ term job creation in Russia and/or in the US. R&D was conducted in two Russian Centers (one in Tomsk and Seversk, the other in Moscow) under the guidance ofPVI personnel and the BNL PI. Multiple approaches were pursued, developed, and tested at various locations with the best candidate for commercialization delivered and tested at on an implanter at the PVI client Axcelis. Technical developments were exciting: record output currents of high charge state phosphorus and antimony were achieved; a Calutron-Bemas ion source with a 70% output of boron ion current (compared to 25% in present state-of-the-art). Record steady state output currents of higher charge state phosphorous and antimony and P ions: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb {sup 4 +}, Sb{sup 5+}, and Sb{sup 6+} respectively. Ultimate commercialization goals did not succeed (even though a number of the products like high

  5. Color centers of a borosilicate glass induced by 10 MeV proton, 1.85 MeV electron and 60Co-γ ray

    International Nuclear Information System (INIS)

    Du, Jishi; Wu, Jiehua; Zhao, Lili; Song, Lixin

    2013-01-01

    Optical absorption spectra, electron paramagnetic resonance (EPR) spectra, Raman spectra of a borosilicate glass after irradiation by 10 MeV proton, 1.85 MeV electron and 60 Co-γ ray were studied. The process of irradiation inducing color centers in the glass was discussed. The band gap of the glass before and after 60 Co-γ ray irradiation was studied using Mott and Davis's theory, and it was found that calculated change of the band gap introduced a paradox, because Mott and Davis's theory on the band gap cannot be adopted in the study on the irradiated glass. - Highlights: ► All the three types of irradiation induce the same types of color centers. ► Calculated change of the band gap introduced a paradox. ► Mott and Davis's theory on band gap cannot be adopted in the irradiated glass

  6. Measurement of the distributions of internuclear separations in 3.0-MeV H2+ and 3.63-MeV HeH+ beams

    International Nuclear Information System (INIS)

    Kanter, E.P.; Cooney, P.J.; Gemmell, D.S.; Vager, Z.; Pietsch, W.J.; Zabransky, B.J.

    1979-01-01

    Angular distributions of charged dissociation fragments are measured for 3.0-MeV H 2 + and 3.63-MeV HeH + ions incident on approx. 160 A carbon targets. By using the reflection method for a pure Coulomb potential, there are unfolded from these data the distributions of internuclear separations for each molecular-ion species prior to dissociation. These results are insensitive to ion-source conditions. For H 2 + this distribution, while approx. 2 times wider than a pure ground vibrational state population, is markedly different from the Franck-Condon distribution that has been previously assumed by other authors with similar rf and duo-plasmatron ion sources. For HeH + the distribution is slightly broader (approx. 1.5 times) than that expected for a pure ground state population. From the data, the initial vibrational state population in the incident beam can be extracted. 11 references

  7. Nuclear and activation characteristics of materials in 14.1-MeV and 2.5-MeV neutron field

    International Nuclear Information System (INIS)

    Seki, Yasushi; Takeyasu, Yuuichi.

    1988-11-01

    The nuclear and activation characteristics of various materials and elements of interest in terms of fusion reactor design are calculated and the results are graphically shown. The elements and materials are placed in a simple geometry modelling a blanket and shield of a fusion reactor. The neutrons with 14.1-MeV and 2.5-MeV energy are generated from the region represented as D-T and D-D plasma, respectively. The following activation characteristics after neutron irradiation are shown for each material and element; 1. Time evolution of induced activity, 2. Time evolution of decay heat, 3. Delayed gamma-ray dose distribution, 4. Decay heat distribution. In addition to the above activation characteristics, nuclear characteristics during the neutron irradiation, e.g. neutron energy spectra, neutron and gamma-ray flux distribution, nuclear heating distributions, and neutron and gamma-ray dose rate are also shown. (author)

  8. Experimental and Calculated Effectiveness of a Radiochromic Dye Film to Stopping 21 MeV 7Li- and 64 MeV 16O Ions

    DEFF Research Database (Denmark)

    Olsen, Kjeld J; Hansen, Johnny

    1984-01-01

    Relative radiation effectiveness, RE, of 21 MeV 7Li and 64 MeV 16O ions being completely stopped in a tissue equivalent film dose meter has been measured as a function of penetration depth and energy, and the results have been compared with calculations based on a δ-ray theory for heavy charged...... particles developed by Katz et al. The experiment was designed to test calculations particularly in the Bragg-peak region of the slowing down particles where significant deviation between theory and experiment was found. Fitting of the characteristic D37 dose and the size of the radiation sensitive element...... in the detector, which are important parameters in the theoretical model, does not improve the overall correlation between theory and experiment. It is concluded that disagreement between theoretical and experimental RE-values below 1.5 MeV/amu is partly due to lack of equivalence between the δ-ray spectrum...

  9. Measurement of the energy spectrum with proportional counters with spherical cathodes between 20 keV and 2.5 MeV with the propagation of 14 MeV neutrons in liquid nitrogen and liquid air

    International Nuclear Information System (INIS)

    Schneider-Kuehnle, P.

    1974-01-01

    This work deals with the measurement of the energy spectrum of a 14 MeV neutron source in liquid nitrogen and liquid air in the energy region of 20 keV to 2.5 MeV as a function of the distance from the source. The measured results together with those of a scintispectrometer which measures the energies between 2.5 MeV and 14 MeV, are to serve as experimentally-supported input data for shielding calculations and are to enable the checking of transport theoretical calculations. (orig./LH) [de

  10. Design study of prototype accelerator and MeV test facility for demonstration of 1 MeV, 1 A negative ion beam production

    International Nuclear Information System (INIS)

    Inoue, Takashi; Hanada, Masaya; Miyamoto, Kenji; Ohara, Yoshihiro; Okumura, Yoshikazu; Watanabe, Kazuhiro; Maeno, Shuichi.

    1994-08-01

    In fusion reactors such as ITER, a neutral beam injector of MeV class beam energy and several tens MW class power is required as one of candidates of heating and current drive systems. However, the beam energy of existing high power accelerators are one order of magnitude lower than the required value. In order to realize a neutral beam injector for the fusion reactor, 'Proof-of-Principle' of such high energy acceleration is a critical issue at a reactor relevant beam current and pulse length. An accelerator and an accelerator facility which are necessary to demonstrate the Proof-of-Principle acceleration of negative ion beams up to 1 MeV, have been designed in the present study. The accelerator is composed of a cesium-volume type ion source and a multi-stage electrostatic acceleration system [Prototype Accelerator]. A negative hydrogen ion beam with the current of about one ampere (1 A) can be accelerated up to 1 MeV at a low operating pressure. Two types of acceleration system, a multi-multi type and a multi-single type, have been studied. The test facility has sufficient capability for the test of the Prototype Accelerator [MeV Test Facility]. The dc high voltage generator for negative ion acceleration is a Cockcroft-Walton type and capable of delivering 1 A at 1 MV (=1 MW) for 60 s. High voltage components including Prototype Accelerator are installed in a SF 6 vessel pressurized at 6 kg/cm 2 to overcome high voltage gradients. The vessel and the beamline are installed in a X-ray shield. (author)

  11. Fusion with projectiles from carbon to argon at energies between 20A MeV and 60A MeV

    International Nuclear Information System (INIS)

    Galin, J.

    1986-01-01

    Fusion reactions are known to be the dominant reaction channel at low bombarding energies and can now be investigated with a large variety of projectiles at several tens of MeV per nucleon. The gross characteristics of the fusion process can be studied by measuring global quantities, such as the linear momentum transferred from projectile to target and the dissipated energy of the reaction. The strong correlation between these two quantities is demonstrated at moderate bombarding energies, with a Ne projectile on a U target. It is expected that light particle (charged or neutron) multiplicity measurements can be extended to this higher energy domain and be used to selectively filter these collisions, according to their degree of violence. A review of the linear momentum transfer is made, considering essentially heavy targets and two important parameters in the entrance channel: the projectile energy and its mass. Over a broad mass range, and for energies up to 30A MeV, the momentum transfer scales with the mass of the projectile. At 30A MeV, the most probable value of projectile momentum transferred to the fused system is 80%, and this represents roughly 180 MeV/c per projectile nucleon. At higher bombarding energies, the momentum distribution in the fused systems, as observed from binary fission events, seems to depend on the mass of the projectile. Further studies are still needed to understand this behavior. Finally, the decay of highly excited (E* similarly ordered 500-800 MeV) fused systems, with masses close to 270 amu, is studied from the characteristics of both fusion fragments and light charged particles. It is shown that thermal equilibrium is reached before fission, even for such high energy deposition. However, the decay sequence is sensitive to dynamical effects and does not depend only on available phase space

  12. Digital neutron/gamma discrimination with an organic scintillator at energies between 1 MeV and 100 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Comrie, A.C. [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Buffler, A., E-mail: andy.buffler@uct.ac.za [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Smit, F.D. [iThemba LABS, Somerset West 7129 (South Africa); Wörtche, H.J. [INCAS" 3, Dr. Nassaulaan 9. 9400 AT Assen (Netherlands)

    2015-02-01

    Three different digital implementations of pulse shape discrimination for pulses from an EJ301 liquid scintillator detector are presented, and illustrated with neutrons and gamma-rays produced by an Am–Be radioisotopic source, a D–T generator and beams produced by cyclotron-accelerated protons of energies 42, 62 and 100 MeV on a Li target. A critical comparison between the three methods is provided.

  13. 200 MeV proton scattering on nuclei. Energetic proton analysis at large angle

    International Nuclear Information System (INIS)

    Chaigne, G.

    1983-01-01

    By means of a magnetic spectrometer for which has been realized an acceptance's programme, cross-sections for backward emission have been measured (100 MeV till the cinematic limit) (102 0 to 106 0 ) in the interaction proton-nucleus at 200 MeV from light, medium and heavy target. Our experimental set-up used from a polyethylene target (CH2) allowed to obtain, for the elastic cross-section (p,p), values in agreement with those ones determined by an analyse in phase-shift at 200 MeV. A comparison of our experimental spectra with the theory based on the Q.T.B.S. model (Quasi Two Body Scaling) and on a more conventional one of intranuclear cascades showed that the knock out mechanisms inside the nucleus are always unknown [fr

  14. Measurement of the angular distribution of 14 MeV neutrons scattered inelastically from the 0+ level at 7.65 MeV to {sup 12}C (1964); Mesure de la distribution angulaire a 14 MeV de neutrons de diffusion inelastique sur le niveau 0+ de 7,65 MeV du {sup 12}C (1964)

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, I [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1963-11-15

    Inelastic scattering of 14 MeV neutrons from {sup 12}C and angular distribution for the 0{sup +} (7,65 MeV) level, with a time-of-flight spectrometer (over-all resolution 1.4 ns), gives strong forward maximum {sigma}({theta} 15 deg.) {approx_equal} 8 mb/sr suggesting a direct-interaction process. (author) [French] Realisation d'un spectrometre de neutrons rapides a temps-de-vol de resolution totale 1,4 ns. Application: {sup 12}C (n,n') {sup 12}C (7,65 MeV) donnant {sigma}{sub t} {approx_equal} 20 mb, une forte emission vers l'avant {sigma}({theta} 15 deg.) {approx_equal} 8 mb/sr indiquont un processus d'interaction directe. (auteur)

  15. A possible approach to 14MeV neutron moderation: A preliminary study case.

    Science.gov (United States)

    Flammini, D; Pilotti, R; Pietropaolo, A

    2017-07-01

    Deuterium-Tritium (D-T) interactions produce almost monochromatic neutrons with about 14MeV energy. These neutrons are used in benchmark experiments as well as for neutron cross sections assessment in fusion reactors technology. The possibility to moderate 14MeV neutrons for purposes beyond fusion is worth to be studied in relation to projects of intense D-T sources. In this preliminary study, carried out using the MCNP Monte Carlo code, the moderation of 14MeV neutrons is approached foreseeing the use of combination of metallic materials as pre-moderator and reflectors coupled to standard water moderators. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Neutron-induced 2.2 MeV background in gamma ray telescopes

    International Nuclear Information System (INIS)

    Zanrosso, E.M.; Long, J.L.; Zych, A.D.; White, R.S.; Hughes Aircraft Co., Los Angeles, CA)

    1985-01-01

    Neutron-induced gamma ray production is an important source of background in Compton scatter gamma ray telescopes where organic scintillator material is used. Most important is deuteron formation when atmospheric albedo and locally produced neutrons are thermalized and subsequently absorbed in the hydrogenous material. The resulting 2.2 MeV gamma line essentially represents a continuous isotropic source within the scintillator itself. Interestingly, using a scintillator material with a high hydrogen-to-carbon ratio to minimize the neutron-induced 4.4 MeV carbon line favors the np reaction. The full problem of neutron-induced background in Compton scatter telescopes has been previously discussed. Results are presented of observations with the University of California balloon-borne Compton scatter telescope where the 2.2 MeV induced line emission is prominently seen

  17. Proton-nucleus interactions at 640 MeV accompanied by backward emission of energetic protons

    International Nuclear Information System (INIS)

    Komarov, V.I.; Kosarev, E.G.; Mueller, H.; Netzband, D.; Toneev, V.D.; Stiehler, T.; Tesch, S.; Gudima, K.K.; Mashnik, S.G.

    1979-03-01

    Spectra of protons of energies between 50 and 145 MeV emitted from carbon have been measured at angles from 105 0 to 160 0 with respect to the 640 MeV proton beam. The measurements have been carried out both inclusively and in coincidence with protons emitted at forward angles up to +- 40 0 with energies from 255 to 330 MeV. This energy interval has been chosen in accordance with the kinematics of quasifree scattering on two-nucleon groups. Inclusive differential cross sections at 140 0 and coincidence cross sections at the angle pair (-12 0 , 122 0 ) have also been measured with Be, Al, Cu and Pb targets. The data have been compared with the predictions of several models. (author)

  18. Calibration in photon radiation fields with energies above 3 MeV

    International Nuclear Information System (INIS)

    Bueermann, L.

    1997-01-01

    For determination of the response of dosemeters and dose ratemeters for photon energies above 3 MeV, the PTB uses reference radiation fields generated via the nuclear reactions 12 (p, p' γ) 12 C (4.4 MeV) and 19 F(p,αγ) 16 O (6-7 MeV). As a maximum, kerma rates of 1 mGy/h released in air can be achieved at 1 m distance from the target. The air kerma in the reference fields is determined with two different methods, i.e. by spectrometry using a Ge detector, and by ionometry using a graphite cavity ionisation chamber. The total uncertainty of the value determined for the air kerma (collision radiation) in the reference fields is 50% at a confidence level of 68.3%. (orig./CB) [de

  19. Table of nuclear reactions and subsequent radioactive dacays induced by 14-MeV neutrons

    International Nuclear Information System (INIS)

    Tsukada, Kineo

    1977-09-01

    Compilation of the data on nuclear reactions and subsequent radioactive decays induced by 14-MeV neutrons is presented in tabular form for most of the isotopes available in nature and for some of the artificially-produced isotopes, including the following items: Nuclide (isotopic abundance), type of nuclear reaction, reaction Q-value, reaction product, type of decay, decay Q-value, half-life of reaction product, decay product, maximum reaction cross section, neutron energy for maximum cross section, reaction cross section for 14 MeV neutrons, saturated radioactivity induced by irradiation of a neutron flux of 1 n/cm 2 sec for a mol of atoms, and reference for the cross section. The mass number dependence of (n, γ), (n, 2n), (n, p), (n, d), (n, t), (n, 3 He) and (n, α) reaction cross sections for 14-MeV neutrons is given in figures to show general trends of the cross sections

  20. A sub-picosecond pulsed 5 MeV electron beam system

    International Nuclear Information System (INIS)

    Farrell, J. Paul; Batchelor, K.; Meshkovsky, I.; Pavlishin, I.; Lekomtsev, V.; Dyublov, A.; Inochkin, M.; Srinivasan-Rao, T.

    2001-01-01

    Laser excited pulsed, electron beam systems that operate at energies from 1 MeV up to 5 MeV and pulse width from 0.1 to 100 ps are described. The systems consist of a high voltage pulser and a coaxial laser triggered gas or liquid spark gap. The spark gap discharges into a pulse forming line designed to produce and maintain a flat voltage pulse for 1 ns duration on the cathode of a photodiode. A synchronized laser is used to illuminate the photocathode with a laser pulse to produce an electron beam with very high brightness, short duration, and current at or near the space charge limit. Operation of the system is described and preliminary test measurements of voltages, synchronization, and jitter are presented for a 5 MeV system. Applications in chemistry, and accelerator research are briefly discussed

  1. Electrofission of 239Pu in the energy range 7 endash 12 MeV

    International Nuclear Information System (INIS)

    Arruda-Neto, J.D.; Yoneama, M.; Dias, J.F.; Garcia, F.; Reigota, M.A.; Likhachev, V.P.; Guzman, F.; Rodriguez, O.; Mesa, J.

    1997-01-01

    The electrofission cross section of 239 Pu(e,f) is measured between 7 and 12 MeV. The data are analyzed by means of the virtual photon formalism, assuming that E1, E2 (T=0), and M1 transitions are involved. Using known estimates for the E1 and E2 (T=0) fission strengths, it is deduced an M1 fission strength of 19±4μ N 2 concentrated near the fission barrier (between 5.4 and 5.8 MeV). The levels of the 239 Pu transition nucleus are theoretically obtained; a bunch of positive-parity levels shows up between 5.5 and 5.9 MeV, which might well be associated with the deduced M1 strength, since the E2 strength is negligible in this energy interval. copyright 1997 The American Physical Society

  2. Elastic scattering of antiprotons from carbon, calcium, and lead at 180 MeV

    International Nuclear Information System (INIS)

    Garreta, D.; Birien, P.; Bruge, G.; Chaumeaux, A.; Drake, D.M.; Janouin, S.; Legrand, D.; Lemaire, M.C.; Mayer, B.; Pain, J.; Peng, J.C.

    1984-01-01

    Angular distributions for elastic scattering of 180 MeV antiprotons from 12 C, 40 Ca, and 208 Pb have been measured over a wide angular range with a magnetic spectrometer. In general, microscopic calculations agree fairly well with the data. Optical-model fits with Woods-Saxon parametrization determine the magnitude and the relative strength of the real and imaginary potentials at the nuclear surface. When the shape of the potentials is derived from that of the charge distribution, the depth of the real potential is found to be shallow (30 MeV 0 12 C scattering at 46.8 MeV and with a recent analysis of anti p-atom data. (orig.)

  3. The ANL 50 MeV H- Injector: 35 year anniversary

    International Nuclear Information System (INIS)

    Stipp, V.; Brumwell, F.; McMichael, G.

    1996-01-01

    The H - Injector at ANL consists of a 750 keV Cockcroft-Walton preaccelerator and an Alvarez type 50 MeV Linac. The accelerator was originally constructed as the source of protons for the Zero Gradient Synchrotron (ZGS). The first proton beam was extracted from the preaccelerator in 1961. The accelerator is presently used as the injector for the Intense Pulsed Neutron Source (IPNS), a 500 MeV rapid cycling synchrotron with a spallation-neutron target. During most of the time since turn-on over 15 years ago, the IPNS facility availability has rarely dropped below 90% and has averaged 95% over the last ten years. During the same period, the 50 MeV injector availability has averaged 99%. Performance and improvements over the 35 year period is discussed

  4. A direct electron detector for time-resolved MeV electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Vecchione, T.; Denes, P.; Jobe, R. K.; Johnson, I. J.; Joseph, J. M.; Li, R. K.; Perazzo, A.; Shen, X.; Wang, X. J.; Weathersby, S. P.; Yang, J.; Zhang, D.

    2017-03-01

    The introduction of direct electron detectors enabled the structural biology revolution of cryogenic electron microscopy. Direct electron detectors are now expected to have a similarly dramatic impact on time-resolved MeV electron microscopy, particularly by enabling both spatial and temporal jitter correction. Here we report on the commissioning of a direct electron detector for time-resolved MeV electron microscopy. The direct electron detector demonstrated MeV single electron sensitivity and is capable of recording megapixel images at 180 Hz. The detector has a 15-bit dynamic range, better than 30-μmμm spatial resolution and less than 20 analogue-to-digital converter count RMS pixel noise. The unique capabilities of the direct electron detector and the data analysis required to take advantage of these capabilities are presented. The technical challenges associated with generating and processing large amounts of data are also discussed.

  5. /sup 12/C(γ,n) cross section from 30 to 100 MeV

    International Nuclear Information System (INIS)

    Harty, P.D.; Thompson, M.N.; O'Keefe, G.J.

    1988-01-01

    This paper reports a measurement of the differential photoneutron cross section of /sup 12/C at 65 0 , between E/sub γ/ = 30 and 100 MeV. Tagged photons, monochromatic to within 2.6 MeV, were used, thus allowing the cross sections to a wide range of final states to be observed. The results are compared to the photoproton cross section of /sup 12/C, which was measured previously, under similar conditions. Comparisons are also made with calculations based on the quasi-deuteron model, and with calculations by Gari and Hebach, and Cavinato et al. These latter calculations incorporate two-body effects by the inclusion of meson exchange currents. The agreement between these calculations and the measured cross section is in contrast to predictions of a direct, single-nucleon knockout model of the reaction mechanism, indicating the importance of two-body effects in the photoreaction process for energies greater than 50 MeV

  6. Gold standard capture cross section from 100 keV to 15 MeV

    International Nuclear Information System (INIS)

    Ryves, T.B.

    1982-01-01

    The capture cross section of gold is now generally accepted as the principal reference standard, and therefore in this review only gold is considered. Recent measurements of the gold capture cross section in the unresolved region are discussed and compared with the ENDF/B-V evaluation. It is concluded that in the energy interval 100 to 2000 keV the present uncertainty in the evaluation is +-8%, in the interval 2 to 3.5 MeV the uncertainty is +-4%, in ther interval 3.5 to 14 MeV more measurements are needed before a realistic error can be assigned, and from 14 to 15 MeV the uncertainty is +-10%. Several recommendations for future work have been made

  7. Two-body photodisintegration of the deuteron from 100 to 800 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, R.; Ahrens, J.; Altieri, S.; Annand, J.R.M.; Anthony, I.; Audit, G.; Beck, R.; Braghieri, A.; D`Hose, N.; Hall, S.; Isbert, V.; Kellie, J.D.; Kerhoas, S.; MacCormick, M.; MacGeorge, J.C.; Medaglia, R.; Miller, G.J.; Murphy, L.Y.; Owens, R.O.; Pedroni, P.; Pinelli, T.; Tamas, G.; Wallace, P.A. [Glasgow Univ. (United Kingdom). Dept. of Phys. and Astron.]|[Mainz Univ. (Germany). Inst. fuer Kernphys.]|[INFN, Sezione di Pavia (Italy)]|[Pavia Univ. (Italy). Dipartimento di Fisica Nucleare e Teorica]|[CEA-DAPNIA/SPhN, 91 - Gif-sur-Yvette (France)

    1996-06-24

    The total and the differential cross sections for the D({gamma},p)n reaction have been measured over the photon energy range 100-800 MeV at the 855 MeV MAMI Microtron in Mainz. Using the large acceptance detector DAPHNE in conjunction with the Glasgow tagging spectrometer, high precision results with small systematic errors were obtained. The data are presented in the form of thirty-five angular distributions at c.m. proton angles between 30 {sup circle} -160 {sup circle} in 10 {sup circle} intervals and at photon energies in steps of 20 MeV. Previous experimental work is reassessed in the light of the present results and comparison with some recent theoretical calculations. (orig.).

  8. Investigation of the neutron-proton-interaction in the energy range from 20 to 50 MEV

    International Nuclear Information System (INIS)

    Wilczynski, J.

    1984-07-01

    In the framework of the investigation of the isospin singlet part of the nucleon-nucleon-interaction in the energy range below 100 MeV two experiments were conducted, which were selected by sensitivity calculations. At the Karlsruhe polarized neutron facility POLKA the analyzing powers Asub(y) and Asub(yy) of the elastic n vector-p- and n vector-p vector-scattering were measured in the energy range from 20 to 50 MeV. The results of this epxeriment are compared to older data. In the energy range from 20 to 50 MeV the new data were analyzed together with other selected data of the nucleon-nucleon-system in phase shift analyses. The knowledge of the isospin singlet phase shifts 1 P 1 and 3 D 3 was improved by the new data. (orig./HSI) [de

  9. MeV ion-beam analysis of optical data storage films

    Science.gov (United States)

    Leavitt, J. A.; Mcintyre, L. C., Jr.; Lin, Z.

    1993-01-01

    Our objectives are threefold: (1) to accurately characterize optical data storage films by MeV ion-beam analysis (IBA) for ODSC collaborators; (2) to develop new and/or improved analysis techniques; and (3) to expand the capabilities of the IBA facility itself. Using H-1(+), He-4(+), and N-15(++) ion beams in the 1.5 MeV to 10 MeV energy range from a 5.5 MV Van de Graaff accelerator, film thickness (in atoms/sq cm), stoichiometry, impurity concentration profiles, and crystalline structure were determined by Rutherford backscattering (RBS), high-energy backscattering, channeling, nuclear reaction analysis (NRA) and proton induced X-ray emission (PIXE). Most of these techniques are discussed in detail in the ODSC Annual Report (February 17, 1987), p. 74. The PIXE technique is briefly discussed in the ODSC Annual Report (March 15, 1991), p. 23.

  10. Actinide neutron-induced fission up to 20 MeV

    International Nuclear Information System (INIS)

    Maslov, V.M.

    2001-01-01

    Fission and total level densities modelling along with double-humped fission barrier parameters allow to describe available actinide neutron-induced fission cross section data in the incident neutron energy range of ∼ 10 keV - 20 MeV. Saddle asymmetries relevant to shell correction model calculations influence fission barriers, extracted by cross section data analysis. The inner barrier was assumed axially symmetric in case of U, Np and Pu neutron-deficient nuclei. It is shown that observed irregularities in neutron-induced fission cross section data in the energy range of 0.5-3 MeV could be attributed to the interplay of few-quasiparticle excitations in the level density of fissioning and residual nuclei. Estimates of first-chance fission cross section and secondary neutron spectrum model were validated by 238 U fission, (n,2n) and (n,3n) data description up to 20 MeV. (author)

  11. Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes

    International Nuclear Information System (INIS)

    Laurat, M.

    1969-01-01

    A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten μg/cm 2 ) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of 8 Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [fr

  12. Photoresponse of {sup 94}Mo at energies up to 8.6 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Romig, Christopher; Fritzsche, M.; Lindenberg, K.; Pietralla, N.; Savran, D.; Sonnabend, K. [Institut fuer Kernphysik, Technische Universitaet, Darmstadt (Germany); Rusev, G.; Tonchev, A.P.; Tornow, W.; Weller, H.R. [Triangle Universities Nuclear Laboratory, Duke University, Durham, NC (United States); Zilges, A. [Institut fuer Kernphysik, Universitaet Koeln (Germany)

    2009-07-01

    The isotope {sup 94}Mo was investigated in nuclear resonance fluorescence experiments at the High Intensity Photon Setup (HIPS) at the S-DALINAC in Darmstadt using bremsstrahlung photons with energies of 7.65 and 8.6 MeV, respectively, and at the High Intensity {gamma}-ray Source (HI{gamma}S) at Duke University using photons from Laser Compton backscattering. Thereby over 60 excitations were found which could be assigned to {sup 94}Mo due to the highly enriched sample. In the energy region between 5.4 and 8 MeV many transitions could be classified as dipole transitions and cross sections, angular momentum quantum numbers, half-lifes and transition strengths were determined. At HI{gamma}S the parity quantum numbers of 40 excitations between 5.5 and 7.0 MeV could be determined. The methods and results are presented.

  13. Actinide neutron-induced fission up to 20 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V M [Radiation Physics and Chemistry Problems Institute, Minsk-Sosny (Belarus)

    2001-12-15

    Fission and total level densities modelling along with double-humped fission barrier parameters allow to describe available actinide neutron-induced fission cross section data in the incident neutron energy range of {approx} 10 keV - 20 MeV. Saddle asymmetries relevant to shell correction model calculations influence fission barriers, extracted by cross section data analysis. The inner barrier was assumed axially symmetric in case of U, Np and Pu neutron-deficient nuclei. It is shown that observed irregularities in neutron-induced fission cross section data in the energy range of 0.5-3 MeV could be attributed to the interplay of few-quasiparticle excitations in the level density of fissioning and residual nuclei. Estimates of first-chance fission cross section and secondary neutron spectrum model were validated by {sup 238}U fission, (n,2n) and (n,3n) data description up to 20 MeV. (author)

  14. 50 MeV Run of the IOTA / FAST Electron Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Edstrom Jr., D.; et al.

    2017-02-02

    The low-energy section of the photoinjector-based electron linear accelerator at the Fermilab Accelerator Science & Technology (FAST) facility was recently commissioned to an energy of 50 MeV. This linear accelerator relies primarily upon pulsed SRF acceleration and an optional bunch compressor to produce a stable beam within a large operational regime in terms of bunch charge, total average charge, bunch length, and beam energy. Various instrumentation was used to characterize fundamental properties of the electron beam including the intensity, stability, emittance, and bunch length. While much of this instrumentation was commissioned in a 20 MeV running period prior, some (including a new Martin- Puplett interferometer) was in development or pending installation at that time. All instrumentation has since been recommissioned over the wide operational range of beam energies up to 50 MeV, intensities up to 4 nC/pulse, and bunch structures from ~1 ps to more than 50 ps in length.

  15. Small angle particle-particle correlation measurements in the reactions 280 MeV 40Ar+27Al and 670 MeV 55Mn+12C

    International Nuclear Information System (INIS)

    Milosevich, Zoran; Vardaci, Emanuele; DeYoung, Paul A.; Brown, Craig M.; Kaplan, Morton; Whitfield, James P.; Peterson, Donald; Dykstra, Christopher; Barton, Matthew; Karol, Paul J.; McMahan, Margaret A.

    2001-01-01

    Small-angle particle-particle correlations were measured in the two matching reactions 280 MeV 40 Ar+ 27 Al and 670 MeV 55 Mn+ 12 C. These two reactions were used to produce the composite nucleus, 67 Ga*, at the same initial excitation energy of 127 MeV, but with different entrance channel angular momentum distributions. A simple trajectory model was used to compute the average emission times between various particle pairs, and comparisons with the data show that there is a significant difference in the deexcitation of the composite nucleus formed from the two reactions. Statistical model calculations were compared to the experimental observations with the added constraint that the model input parameters were consistent with those derived from observed charged-particle energy spectra and angular distributions. It was found that the calculated correlation functions were insensitive to the input spin distributions, but agreed fairly well with the data from the lower-spin system. The higher-spin reaction data were poorly reproduced by the calculations

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

    Energy Technology Data Exchange (ETDEWEB)

    Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Brossard, Tom [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Roussin, Ethan [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Jonah, Charles [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hafenrichter, Lohman [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Krebs, John [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2016-10-31

    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-ABO 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.

  17. Analyzing power for the 16O(p,n)16F (4-, 6.37 MeV) reaction at 134 MeV

    International Nuclear Information System (INIS)

    Madey, R.; Fazely, A.; Anderson, B.D.; Baldwin, A.R.; Kalenda, A.M.; McCarthy, R.J.; Tandy, P.C.; Watson, J.W.; Bertozzi, W.; Buti, T.; Finn, M.; Kovash, M.; Pugh, B.; Foster, C.C.

    1982-01-01

    We measured the analyzing power for the 16 O(p,n) 16 F (4 - , 6.37 MeV) reaction at 134.0 MeV and the differential cross section for the same reaction at 135.2 MeV. The shape of the cross section for the transition to this unnatural parity stretched state is described well by a distorted-wave impulse-approximation calculation using a (πd/sub 5/2/, νp/sub 3/2//sup ts-1/) 4 /sub -/ configuration and the effective interaction derived by Love and Franey from nucleon-nucleon phase shifts. The analyzing power from this calculation reproduces all of the qualitative features of the data and supports the use of the impulse approximation as an excellent starting point for describing the reaction mechanism. Quantitative agreement between the experimental and theoretical analyzing power can be improved by eliminating the imaginary tensor term of this interaction and taking the real part to be that derived by Love from the Sussex matrix elements. The sensitivity of the calculations to the choice of optical potentials and the importance of spin-orbit distortion is explored

  18. Energy dissipation process for 100-MeV protons and the nucleon-nucleon interactions in nuclei

    International Nuclear Information System (INIS)

    Cowley, A.A.; Chang, C.C.; Holmgren, H.D.; Silk, J.D.; Hendrie, D.L.; Koontz, R.W.; Roos, P.G.; Samanta, C.; Wu, J.R.

    1980-01-01

    Coincidence studies of two protons emitted from p+ 58 Ni at 100 MeV have been carried out. The proton spectra in coincidence with scattered protons suffering an average energy loss of 60 MeV are similar to those resulting from 60-MeV incident protons. This suggests that the initial interaction of the incident proton is with a bound nucleon and that one or both of these nucleons are emitted or initiates a cascade leading to more complex states

  19. Evidence for a resonant behaviour in e+e- annihilation into hadrons, around 1820 MeV, at Adone

    International Nuclear Information System (INIS)

    Bacci, C.; Zorzi, G. de; Penso, G.; Stella, B.; Baldini-Celio, R.; Capon, G.; Fabbro, R. del; Iarocci, E.; Murtas, G.P.; Spinetti, M.

    1977-01-01

    Multihadron production has been measured at the Adone e + e - storage ring in the c.m. energy region 1600/1900 MeV. A resonant behaviour is observed, centered at 1819 +- 5 (+-2) MeV, with a width of 24 +-5 (+-4) MeV. This effect is observed only in the events with 3 or 4 charged particles together with photons, but not in those without photons. (Auth.)

  20. Acquisition of the ANL 4-MeV electrostatic accelerator. Progress report, September 1, 1975--August, 1976

    International Nuclear Information System (INIS)

    Dixon, D.R.

    1976-01-01

    The operation of the ANL 4-MeV accelerator for the reporting period September 1, 1975 through August 31, 1976 is described. Some improvements and modifications to the accelerator and associated equipment, as well as maintenance problems are reported. Activities on the three research projects and a subsequent modification are summarized. Progress on the shift of research activities from the BYU 2-MeV accelerator to the 4-MeV accelerator is described

  1. Valence and inner proton hole states in 207Tl via the (d,3He) reaction at 108 MeV

    International Nuclear Information System (INIS)

    Langevin-Joliot, H.; Gerlic, E.; Guillot, J.; Van de Wiele, J.

    1983-01-01

    The excitation energy spectra of the residual nucleus 207 Tl have been investigated up to 14 MeV using the (d, 3 He) reaction at 108 MeV. New groups and high lying structures are first observed up to 8.3 MeV, in addition to the five known low lying levels. Beyond a minimum at 7.13 MeV, weaker structures are observed riding over an asymetric bump located around 9 MeV. DWBA analysis of angular distributions have allowed l attributions and the determination of valence and inner hole spectroscopic factors. It is found that the valence levels at 1.33 MeV, 1.67 MeV and 3.47 MeV exhaust respectively about 65%, 60% and 45% of the 1hsub(11/2), 2dsub(5/2) and 1gsub(7/2) sum rules. The missing strengths are found below 8.3 MeV. The 2dsub(5/2) and 1gsub(7/2) holes contribute mainly to some well concentrated groups, whereas the 1hsub(11/2) strength is distributed more smoothly. Small contributions of 1gsub(9/2) and 2p strengths are tentatively identified below 7.13 MeV. The highest lying energy region up to 14 MeV may approximately account for the 1gsub(9/2) and (1fsub(5/2)) total sum-rule and about 70% of the 2p strength. The 1gsub(9/2) strength gives the largest contribution to the asymetric bump around 9 MeV. The deduced experimental strength functions are compared with theoretical calculations

  2. The Karlsruhe Neutron Transmission Experiment (KANT): Spherical shell transmission measurements with 14 MeV neutrons on beryllium

    International Nuclear Information System (INIS)

    Moellendorff, U. von; Fischer, U.; Giese, H.; Kappler, F.; Tayama, R.; Wiegner, E.; Klein, H.; Alevra, A.

    1996-01-01

    This is a set of viewgraphs (no additional text) of a presentation on spherical shell transmission measurements with 14 MeV neutrons on beryllium; the cross for 9 Be(n,2n)2α for the energy range between threshold (1.85 MeV) and 20 MeV neutron energy is measured and the measurement is compared with the literature. Also, neutron leakage multiplication in spherical Be shells with various thicknesses are presented. Figs, tabs

  3. Determination of partial decay widths for the 2-, 8.87 MeV level in 16O

    International Nuclear Information System (INIS)

    Vermeer, W.J.; Poletti, A.R.

    1982-01-01

    The E2/M1 mixing ratios for the decays of the 2 - , 8.87 MeV level in 16 O to the 1 - , 7.12 MeV and 3 - , 6.13 MeV levels were measured. The results were delta(2 - → 1 - )= + 2.1 +- 0.5 and delta(2 - → 3 - )= + 2.90 +- 0.20. These are compared with previous experiments and with shell-model predictions. (author)

  4. Measurement of pair production cross sections in Ge for the 1. 238-3. 548 MeV energy range

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, R K; Singh, K; Sahota, H S

    1985-02-28

    Pair production cross sections have been determined for the 1.238-3.548 MeV energy range in germanium (Z = 32) using a Ge(Li) gamma ray detector. The experimental results have been compared with the theoretical cross sections of previous workers. The results of the present measurements agree with the Bethe-Heitler results down to 1.771 MeV. However, at 1.238 MeV the experimental results are higher than all the theories.

  5. Neutron induced fission of U isotopes up to 100 MeV

    International Nuclear Information System (INIS)

    Lestone, J.P.; Gavron, A.

    1993-01-01

    We have developed a statistical model description of the neutron induced fission of U isotopes using densities of intrinsic states and spin cut off parameters obtained directly from appropriate Nilsson model single particle levels. The first chance fission cross sections are well reproduced when the rotational contributions to the nuclear level densities are taken into account. In order to fit the U(n,f) cross sections above the threshold of second chance fission, we need to: (1) assume that the triaxial level density enhancement is washed out at an excitation energy of ∼7 MeV above the triaxial barriers with a width of ∼1 MeV, implying a γ deformation for the first barriers of 10 degree < γ < 20 degree; and (2) include pre-equilibrium particle emission in the calculations. Above an incoming neutron kinetic energy of ∼17 MeV our statistical model U(n,f) cross sections increasingly overestimate the experimental data when so called ''good'' optical model potentials are used to calculate the compound nucleus formation cross sections. This is not surprising since at these high energies little data exists on the scattering of neutrons to help guide the choice of optical model parameters. A satisfactory reproduction of all the available U(n,f) cross sections above 17 MeV is obtained by a simple scaling of our calculated compound nucleus formation cross sections. This scaling factor falls from 1.0 at 17 MeV to 0.82 at 100 MeV

  6. Energy monitoring device for 1.5-2.4 MeV electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Fuochi, P.G., E-mail: fuochi@isof.cnr.i [CNR-ISOF, Via P. Gobetti 101, I-40129 Bologna (Italy); Lavalle, M.; Martelli, A. [CNR-ISOF, Via P. Gobetti 101, I-40129 Bologna (Italy); Kovacs, A. [Institute of Isotopes, HAS, P.O.Box 77, H-1525 Budapest (Hungary); Mehta, K. [Arbeiterstrandbad Strasse 72, Vienna, A-1210 (Austria); Kuntz, F.; Plumeri, S. [Aerial, Parc d' Innovation Rue Laurent Fries F-67400 Illkirch (France)

    2010-03-11

    An easy-to-use and robust energy monitoring device has been developed for reliable detection of day-to-day small variations in the electron beam energy, a critical parameter for quality control and quality assurance in industrial radiation processing. It has potential for using on-line, thus providing real-time information. Its working principle is based on the measurement of currents, or charges, collected by two aluminium absorbers of specific thicknesses (dependent on the beam energy), insulated from each other and positioned within a faraday cup-style aluminium cage connected to the ground. The device has been extensively tested in the energy range of 4-12 MeV under standard laboratory conditions at Institute of Isotopes and CNR-ISOF using different types of electron accelerators; namely, a TESLA LPR-4 LINAC (3-6 MeV) and a L-band Vickers LINAC (7-12 MeV), respectively. This device has been also tested in high power electron beam radiation processing facilities, one equipped with a 7-MeV LUE-8 linear accelerator used for crosslinking of cables and medical device sterilization, and the other equipped with a 10 MeV Rhodotron TT100 recirculating accelerator used for in-house sterilization of medical devices. In the present work, we have extended the application of this method to still lower energy region, i.e. from 1.5 to 2.4 MeV. Also, we show that such a device is capable of detecting deviation in the beam energy as small as 40 keV.

  7. Energy monitoring device for 1.5-2.4 MeV electron beams

    Science.gov (United States)

    Fuochi, P. G.; Lavalle, M.; Martelli, A.; Kovács, A.; Mehta, K.; Kuntz, F.; Plumeri, S.

    2010-03-01

    An easy-to-use and robust energy monitoring device has been developed for reliable detection of day-to-day small variations in the electron beam energy, a critical parameter for quality control and quality assurance in industrial radiation processing. It has potential for using on-line, thus providing real-time information. Its working principle is based on the measurement of currents, or charges, collected by two aluminium absorbers of specific thicknesses (dependent on the beam energy), insulated from each other and positioned within a faraday cup-style aluminium cage connected to the ground. The device has been extensively tested in the energy range of 4-12 MeV under standard laboratory conditions at Institute of Isotopes and CNR-ISOF using different types of electron accelerators; namely, a TESLA LPR-4 LINAC (3-6 MeV) and a L-band Vickers LINAC (7-12 MeV), respectively. This device has been also tested in high power electron beam radiation processing facilities, one equipped with a 7-MeV LUE-8 linear accelerator used for crosslinking of cables and medical device sterilization, and the other equipped with a 10 MeV Rhodotron TT100 recirculating accelerator used for in-house sterilization of medical devices. In the present work, we have extended the application of this method to still lower energy region, i.e. from 1.5 to 2.4 MeV. Also, we show that such a device is capable of detecting deviation in the beam energy as small as 40 keV.

  8. Facility for the measurement of proton polarization in the range 50-70 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, M; Sakaguchi, H; Sakamoto, H; Ogawa, H; Cynshi, O; Kobayashi, S [Kyoto Univ. (Japan). Dept. of Physics; Kato, S [Osaka Univ., Toyonaka (Japan). Lab. of Nuclear Studies; Matsuoka, N; Hatanaka, K; Noro, T [Osaka Univ., Toyonaka (Japan). Research Center for Nuclear Physics

    1983-07-01

    A proton polarimetry facility based on silicon analyzers combined with high-purity germanium detectors is described. The scattering efficiency is 1.5 x 10/sup -5/ at 60 MeV with an effective analyzing power of 0.71 and the energy resolution is about 300 keV fwhm. The facility has succeeded in measuring the depolarization in p-/sup 13/C elastic scattering separated clearly from inelastic events. In order to use a silicon detector as an analyzer target, measurements of cross sections and analyzing powers have been performed at proton energies of 65, 60, 55, 50 and 45 MeV.

  9. The KAERI 10 MeV Electron Linac - Description and Operational Manual

    International Nuclear Information System (INIS)

    Lee, Byung Cheol; Park, Seong Hee; Jung, Young Uk; Han, Young Hwan; Kang, Hee Young

    2005-06-01

    The objective of this technical report is to guide the right operation and maintenance of the KAERI electron linac system. The KAERI electron linac system consists of 2 MeV injector based on 176 MHz Normal conducting RF (Radio Frequency)cavity and 10 MeV main accelerator based on 352 MHz Superconducting RF cavity, electron beamlines (injection and extraction). Since a electron accelerator generates hazard radiation, this system is located at the shielded room in basement and we can operate the system using the remote control system. It includes the description and the operational manual as well as the detailed technical direction for trouble shooting

  10. Using 3.05 MeV resonance for determination of oxygen impurities

    International Nuclear Information System (INIS)

    Burkova, I.E.; Polyanskij, V.N.; Yatis, A.A.

    1983-01-01

    The method of determining oxygen impurities behind thin films using the isolated resonance in the 16 O(α, α) 16 O reaction at E=3.048 MeV with the width GITA approximately 20 keV, is considered. Cross section in resonance is σsUb(R) = 0.95 b apd it increases cross section of Rutherford scattering by the factor of 25. The conclusion is made on the possibility of using 3.048 MeV resonance when investigating Me-Si film structures

  11. Characterisation of a Compton suppressed Clover detector for high energy gamma rays (=<11MeV)

    International Nuclear Information System (INIS)

    Saha Sarkar, M.; Kshetri, Ritesh; Raut, Rajarshi; Mukherjee, A.; Sinha, Mandira; Ray, Maitreyi; Goswami, A.; Roy, Subinit; Basu, P.; Majumder, H.; Bhattacharya, S.; Dasmahapatra, B.

    2006-01-01

    Gamma ray spectra of two (p,γ) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11MeV

  12. Characterisation of a Compton suppressed Clover detector for high energy gamma rays (=<11MeV)

    Energy Technology Data Exchange (ETDEWEB)

    Saha Sarkar, M. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)]. E-mail: maitrayee.sahasarkar@saha.ac.in; Kshetri, Ritesh [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Raut, Rajarshi [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Mukherjee, A. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Sinha, Mandira [Gurudas College, Narkeldanga, Kolkata-700054 (India); Ray, Maitreyi [Behala College, Parnashree, Kolkata-700060 (India); Goswami, A. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Roy, Subinit [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Basu, P. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Majumder, H. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Bhattacharya, S. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Dasmahapatra, B. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)

    2006-01-01

    Gamma ray spectra of two (p,{gamma}) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11MeV.

  13. The KAERI 10 MeV Electron Linac - Description and Operational Manual

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Cheol; Park, Seong Hee; Jung, Young Uk; Han, Young Hwan; Kang, Hee Young

    2005-06-15

    The objective of this technical report is to guide the right operation and maintenance of the KAERI electron linac system. The KAERI electron linac system consists of 2 MeV injector based on 176 MHz Normal conducting RF (Radio Frequency)cavity and 10 MeV main accelerator based on 352 MHz Superconducting RF cavity, electron beamlines (injection and extraction). Since a electron accelerator generates hazard radiation, this system is located at the shielded room in basement and we can operate the system using the remote control system. It includes the description and the operational manual as well as the detailed technical direction for trouble shooting.

  14. Radiation hardness of a single crystal CVD diamond detector for MeV energy protons

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yuki, E-mail: y.sato@riken.jp [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Shimaoka, Takehiro; Kaneko, Junichi H. [Graduate School of Engineering, Hokkaido University, N13, W8, Sapporo 060-8628 (Japan); Murakami, Hiroyuki [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Isobe, Mitsutaka; Osakabe, Masaki [National Institute for Fusion Science, 322-6, Oroshi-cho Toki-city, Gifu 509-5292 (Japan); Tsubota, Masakatsu [Graduate School of Engineering, Hokkaido University, N13, W8, Sapporo 060-8628 (Japan); Ochiai, Kentaro [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Chayahara, Akiyoshi; Umezawa, Hitoshi; Shikata, Shinichi [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)

    2015-06-01

    We have fabricated a particle detector using single crystal diamond grown by chemical vapor deposition. The irradiation dose dependence of the output pulse height from the diamond detector was measured using 3 MeV protons. The pulse height of the output signals from the diamond detector decreases as the amount of irradiation increases at count rates of 1.6–8.9 kcps because of polarization effects inside the diamond crystal. The polarization effect can be cancelled by applying a reverse bias voltage, which restores the pulse heights. Additionally, the radiation hardness performance for MeV energy protons was compared with that of a silicon surface barrier detector.

  15. The RF system for the 70 MeV linac injector

    International Nuclear Information System (INIS)

    Planner, C.W.

    1975-12-01

    The Radio Frequency System for the 70 MeV Linac Injector for Nimrod is required to power the four Accelerating Cavities and the Buncher and Debuncher Cavities. The frequency of operation is 202.5 MHz and is determined by the use of existing equipment from the redundant 50 MeV Proton Linac for the second and third accelerating cavities and the buncher and de-buncher cavities. The subject is discussed under the following headings: low power drive chain; RF feed lines; cavity field level stabilisation. Circuit diagrams are presented. (U.K.)

  16. MeV ion loss during 3He minority heating in TFTR

    International Nuclear Information System (INIS)

    Zweben, S.J.; Hammett, G.; Boivin, R.; Phillips, C.; Wilson, R.

    1992-01-01

    The loss of MeV ions during 3 He ICRH minority heating experiments has been measured using scintillator detectors near the wall of TFTR. The observed MeV ion losses to the bottom (90 degrees poloidal) detector are generally consistent with the expected first-orbit loss of D- 3 He alpha particle fusion products, with an inferred global reaction rate up to ∼10 16 reactions/sec. A qualitatively similar but unexpectedly large loss occurs 45 degrees poloidally below the outer midplane. This additional loss might be due to ICRH tail ions or to ICRH wave-induced loss of previously confined fusion products

  17. MeV He microbeam analysis of a semiconductor integrated circuit

    International Nuclear Information System (INIS)

    Zhu Peiran; Liu Jiarui; Zhang Jinping; Yin Shiduan

    1989-01-01

    An MeV He + microbeam has been used to analyse a microscale semiconductor structure. The 2 MeV He + ion beam is limited to 25 μm diameter by a set of diaphragms and is further focused by a quadrupole quadruplet to 3μm diameter. The incident beam current on the sample is about 0.3 nA. The Rutherford backscattering (RBS) technique is applied to the measurement of the composition and depth profile in the near-surface region of a semiconductor integrated circuit. (author)

  18. Neutron-induced charged-particle emission studies below 100 MeV at WNR

    Energy Technology Data Exchange (ETDEWEB)

    Haight, R.C.; Lee, T.M.; Sterbenz, S.M. [and others

    1994-07-01

    Charged-particles produced by neutron bombardment of selected targets with Z=5 through 53 have been studied for neutron energies from 1 MeV to about 100 MeV using the spallation neutron source at WNR/LAMPF. Particle detection with energy measurement and particle identification is accomplished by two-element {Delta}E-E counters, three-element {Delta}E{sub l}-{Delta}E{sub 2}-E counters or with pulse-shape discrimination using scintillators directly in the neutron beam. The experimental techniques for these measurements are described and comparisons made among the different approaches. This presentation introduces five papers contributed to this conference.

  19. Neutron-induced charged-particle emission studies below 100 MeV at WNR

    International Nuclear Information System (INIS)

    Haight, R.C.; Lee, T.M.; Sterbenz, S.M.

    1994-01-01

    Charged-particles produced by neutron bombardment of selected targets with Z=5 through 53 have been studied for neutron energies from 1 MeV to about 100 MeV using the spallation neutron source at WNR/LAMPF. Particle detection with energy measurement and particle identification is accomplished by two-element ΔE-E counters, three-element ΔE l -ΔE 2 -E counters or with pulse-shape discrimination using scintillators directly in the neutron beam. The experimental techniques for these measurements are described and comparisons made among the different approaches. This presentation introduces five papers contributed to this conference

  20. 6 MeV RF Linac for cargo scanning and industrial radiography

    International Nuclear Information System (INIS)

    2017-01-01

    RF Linac-based X-ray sources are very widely used for cargo-scanning and industrial X-ray radiography applications. A 6 MeV on-axis coupled-cavity S-band RF linac has been designed, developed and tested successfully at Electron Beam Centre, Navi Mumbai. This facility falls under the purview of BARC Safety Council, which has conducted safety reviews and awarded regulatory clearances for the operation of the linac system. This paper outlines the salient features of the 6 MeV linac, its safety aspects and test results. A brief history of regulatory aspects is also presented

  1. Study of the 6Li(p,π+)7Li reaction at 600 MeV

    International Nuclear Information System (INIS)

    Bauer, T.; Beurtey, R.; Boudard, A.; Bruge, G.; Chaumeaux, A.; Couvert, P.; Duhm, H.H.; Garreta, D.; Matoba, M.; Terrein, Y.; Aslanides, E.; Bertini, R.; Brochard, F.; Gorodetzky, Ph.; Hibou, F.; Bimbot, L.; Le Bornec, Y.; Tatischeff, B.; Dillig, M.

    1977-01-01

    The positive pion production through the 6 Li(p,π + ) reaction at 600 MeV has been studied using the high-resolution magnetic spectrometer SPES I. Differential cross sections have been measured from 5 0 to 35 0 sub(lab). The 6 Li(p,π + ) reaction feeds preferentially the 4.63 MeV 7/2 - level of 7 Li. The results of a calculation based on two- and three-nucleon diagrams with π and rho exchange between the projectile and a bound nucleon are also presented. (Auth.)

  2. Scattering of antiprotons from carbon at 46.8 MeV

    International Nuclear Information System (INIS)

    Garetta, D.; Birien, P.; Bruge, G.; Chaumeaux, A.; Janouin, S.; Legrand, D.; Mallet-Lemaire, M.C.; Mayer, B.; Pain, J.; Drake, D.M.; Peng, J.C.

    1984-01-01

    Antiproton-carbon elastic and inelastic scattering cross sections have been measured at 46.8 MeV over an angular range 6 0 0 with a magnetic spectrometer. Fits to the elastic and inelastic 4.44 MeV excited state cross sections put realistic limits on the strengths of the real and imaginary parts of the antiproton-carbon optical potential. The continuum cross section due to carbon break-up appears to be smaller than it is for corresponding proton data. (orig.)

  3. Observations of galactic center for annihilation line at 0.511 MeV

    International Nuclear Information System (INIS)

    Jayanthi, U.B.; Martin, I.M.; Braga, J.; Neri, J.A.C.F.; Jardim, M.V.A.; Rao, K.R.

    1983-10-01

    The presence of the 0.511 MeV gamma line emission from galactic center is well-established from various balloon experiments. Recent results in 1980-82 from balloon and satellite experiments show significant decrease in this line intensity. To confirm these results a fly on balloon is performed with a large area sodium iodide detector to measure 0.511 MeV line from galactic center. The preliminary results indicate flux -3 photons cm -2 s -1 . (Author) [pt

  4. Interpretation of recent positron-electron measurements between 20 and 800 MeV

    International Nuclear Information System (INIS)

    Pellerin, C.J.; Hartman, R.C.

    1975-01-01

    The recent positron and negatron spectra measured by Hartman and Pellerin (see pages 402-407) are discussed with regard to the problem of solar modulation. At energies above 180 MeV, the spherically symmetric Fokker-Planck equation with a diffusion coefficient proportional to particle rigidity provides reasonable fits to both the positron and total electron data. At energies below 180 MeV the data are consistent with a continuation of the same diffusion coefficient and local source of negatrons, or a change in the diffusion coefficient to a constant value. (orig.) [de

  5. Design of the MYRRHA 17-600 MeV Superconducting Linac

    CERN Document Server

    Biarrotte, J-L; Bouly, F; Carneiro, J-P; Vandeplassche, D

    2013-01-01

    The goal of the MYRRHA project is to demonstrate the technical feasibility of transmutation in a 100MWth Accelerator Driven System (ADS) by building a new flexible irradiation complex in Mol (Belgium). The MYRRHA facility requires a 600 MeV accelerator delivering a maximum proton flux of 4 mA in continuous operation, with an additional requirement for exceptional reliability. This paper will briefly describe the beam dynamics design of the main superconducting linac section which covers the 17 to 600 MeV energy range and requires enhanced fault-tolerance capabilities.

  6. Neutron response matrix for unfolding NE-213 measurements to 21 MeV

    International Nuclear Information System (INIS)

    Ingersoll, D.T.; Wehring, B.W.; Johnson, R.H.

    1976-01-01

    A neutron response matrix from measured neutron responses of NE-213 in the energy range of 0.2 to 22 MeV is presented. An interpolation scheme was used to construct an 81-column matrix from the data of Verbinski, Burrus, Love, Zobel, and Hill. As a test of the new response matrix, the Cf-252 neutron spectrum was measured and unfolded using the new response matrix and the FORIST unfolding code. The spectrum agrees well with previous measurements at lower energies, while providing new information above 8 MeV

  7. Two-body photodisintegration of [sup 3]He between 200 and 800 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Isbert, V. (SPhN-DAPNIA, C.E.N. Saclay, 91191 Gif sur Yvette (France)); Audit, G. (SPhN-DAPNIA, C.E.N. Saclay, 91191 Gif sur Yvette (France)); D' Hose, N. (SPhN-DAPNIA, C.E.N. Saclay, 91191 Gif sur Yvette (France)); Kerhoas, S. (SPhN-DAPNIA, C.E.N. Saclay, 91191 Gif sur Yvette (France)); MacCormick, M. (SPhN-DAPNIA, C.E.N. Saclay, 91191 Gif sur Yvette (France)); Tamas, G. (SPhN-DAPNIA, C.E.N. Saclay, 91191 Gif sur Yvette (France)); Wallace, P.A. (SPhN-DAPNIA, C.E.N. Saclay, 91191 Gif sur Yvette (France)); Altieri, S. (INFN-Sezione di Pavia, via Bassi 6, 27100 Pavia (Italy) Dipartimento di Fisica Nucleare e Teorica, Universita degli Studi di Pavia, via Bassi 6, 27100 Pavia (Italy)); Braghieri, A. (INFN-Sezione di Pavia, via Bassi 6, 27100 Pavia (Italy) Dipartimento di Fisica Nucleare e Teorica, Universita degli Studi di Pavia, via Bassi 6, 27100 Pavia (Italy)); Pedroni, P. (INFN-Sezione di Pavia, via Bassi 6, 27100 Pavia (Italy)); Pinelli, T. (INFN-Sezione di Pavia, via Bassi 6; DAPHNE Collaboration

    1994-10-10

    Differential cross sections for the [sup 3]He([gamma],pd) reaction at photon energies between 200 and 800 MeV at all proton c.m. angles between 35[sup circle] and 145[sup circle] have been measured using the tagged photon beam facility of the 855 MeV MAMI accelerator in Mainz. Reaction products were detected using the large acceptance detector DAPHNE. The results confirm the rapid decrease of forward-angle cross sections with increasing E[sub [gamma

  8. MeV He microbeam analysis of a semiconductor integrated circuit

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Peiran; Liu Jiarui; Zhang Jinping; Yin Shiduan

    1989-01-01

    An MeV He/sup +/ microbeam has been used to analyse a microscale semiconductor structure. The 2 MeV He/sup +/ ion beam is limited to 25 /mu/m diameter by a set of diaphragms and is further focused by a quadrupole quadruplet to 3/mu/m diameter. The incident beam current on the sample is about 0.3 nA. The Rutherford backscattering (RBS) technique is applied to the measurement of the composition and depth profile in the near-surface region of a semiconductor integrated circuit.

  9. Calorimetry for absorbed dose measurement at 1-4 MeV electron accelerators

    International Nuclear Information System (INIS)

    Miller, A.

    2000-01-01

    Calorimeters are used for dose measurement, calibration and intercomparisons at industrial electron accelerators, and their use at 10 MeV electron accelerators is well documented. The work under this research agreement concerns development of calorimeters for use at electron accelerators with energies in the range of 2-4 MeV. The dose range of the calorimeters is 3-40 kGy, and their temperature stability after irradiation was found to be sufficient for practical use in an industrial environment. Measurement uncertainties were determined to be 5% at k = 2. (author)

  10. Loss of alpha-like MeV fusion products from TFTR

    International Nuclear Information System (INIS)

    Zweben, S.J.; Boivin, R.L.; Diesso, M.; Hayes, S.E.; Hendel, H.W.; Park, H.; Strachan, J.D.

    1990-03-01

    A detailed comparison between the observed and expected loss of alpha-like MeV fusion products in TFTR is presented. The D-D fusion products (mainly the 1 MeV triton) were measured with an 2-D imaging scintillation detector. The expected first-orbit loss was calculated with a simple Lorentz orbit code. In almost all cases the measured loss was consistent with the expected first-orbit loss model. Exceptions are noted for small major radius plasmas and during strong MHD activity. 37 refs., 28 figs

  11. Surface structural determination of UO2(111) using MeV ions

    International Nuclear Information System (INIS)

    Thompson, K.A.; Ellis, W.P.; Taylor, T.N.; Valone, S.M.; Maggiore, C.J.

    1983-01-01

    The UO 2 (111) surface was studied using MeV ions incident along the and directions. In addition, this surface was well characterized by LEED and Auger analysis. A resonance at 3.05 MeV for 4 He elastic scattering from 16 O made it possible to study the surface peaks for uranium and oxygen simultaneously. By combining previous surface studies with detailed analysis of the surface peaks and rocking curves for this compound material, an outward relaxation of 0.19 A +- 0.01 A was determined for uranium

  12. The gas bubbles distribution in 600 MeV protons irradiated aluminium

    International Nuclear Information System (INIS)

    Gavillet, D.; Martin, J.L.; Victoria, M.; Green, W.

    1984-01-01

    In order to simulate the damage produced by 14 MeV fusion neutrons, thin foils of high purity Al have been irradiated by a proton beam of 580 MeV (120μA). After irradiation at temperatures higher than 0.5 Tm transmission electron microscope observations of gas bubbles distribution were performed. At 200 0 C a uniform distribution of bubbles has been observed inside the grain. The average distance between bubbles and their density have been determined. The gas pressure inside the bubbles has been estimated [fr

  13. 120 MeV Ag ion induced effects in Au/HfO2/Si MOSCAPs

    Science.gov (United States)

    Manikanthababu, N.; Prajna, K.; Pathak, A. P.; Rao, S. V. S. Nageswara

    2018-05-01

    HfO2/Si thinfilms were deposited by RF sputtering technique. 120 MeV Ag ion irradiation has been used to study the electrical properties of Au/HfO2/Si MOSCAPs. SHI (120 MeV Ag) induced annealing, defects creation and intermixing effects on the electrical properties of these systems have been studied. Here, we have observed that the high electronic excitation can cause a significant reduction of leakage currents in these MOSCAP devices. Various quantum mechanical tunneling phenomenon has been observed from the I-V characteristics.

  14. Tokamak ion temperature and poloidal field diagnostics using 3 MeV protons

    International Nuclear Information System (INIS)

    Heidbrink, W.W.; Strachan, J.D.

    1984-10-01

    The 3 MeV protons created by d(d,p)t fusion reactions in a moderately sized tokamak leave the plasma on trajectories determined by the position of their birth and by the poloidal magnetic field. Pitch-angle resolution of the escaping 3 MeV protons can separately resolve the spatial distribution of the d(d,p)t fusion reactions and the poloidal field distribution inside the tokamak. These diagnostic techniques have been demonstrated on PLT with an array of collimated surface barrier detectors

  15. Observation of an eta'/sub c/ candidate state with mass 3592 +- 5 MeV

    International Nuclear Information System (INIS)

    Edwards, C.; Partridge, R.; Peck, C.; Porter, F.C.; Antreasyan, D.; Gu, Y.F.; Kollmann, W.; Richardson, M.; Strauch, K.; Wacker, K.; Weinstein, A.; Aschman, D.; Burnett, T.; Cavalli-Sforza, M.; Coyne, D.; Newman, C.; Sadrozinski, H.F.W.; Gelphman, D.; Hofstadter, R.; Horisberger, R.; Kirkbride, I.; Kolanoski, H.; Koenigsmann, K.; Lee, R.; Liberman, A.; O'Reilly, J.; Osterheld, A.; Pollock, B.; Tompkins, J.; Bloom, E.; Bulos, F.; Chestnut, R.; Gaiser, J.; Godfrey, G.; Kiesling, C.; Lockman, W.; Oreglia, M.; Scharre, D.L.

    1982-01-01

    An eta'/sub c/ candidate state is observed at a mass M = 3592 +- 5 MeV and with a natural linewidth GAMMA<8 MeV (95% confidence level), by using the ''crystal ball'' NaI(Tl) detector at the Stanford Linear Accelerator Center (SPEAR). The evidence is found in the inclusive photon spectrum in decays of the psi'(3684), where a signal is observed corresponding to a radiative transition to this state with branching ratio between 0.2% and 1.3%

  16. Neutron-neutron quasifree scattering in nd breakup at 10 MeV

    Directory of Open Access Journals (Sweden)

    Malone R.C.

    2016-01-01

    We are conducting new measurements of the cross section for nn QFS in nd breakup. The measurements are performed at incident neutron beam energies below 20 MeV. The neutron beam is produced via the 2H(d, n3He reaction. The target is a deuterated plastic cylinder. Our measurements utilize time-of-flight techniques with a pulsed neutron beam and detection of the two emitted neutrons in coincidence. A description of our initial measurements at 10 MeV for a single scattering angle will be presented along with preliminary results. Also, plans for measurements at other energies with broad angular coverage will be discussed.

  17. Intensity maps of MeV electrons and protons below the radiation belt

    International Nuclear Information System (INIS)

    Kohno, T.; Munakata, K.; Murakami, H.; Nakamoto, A.; Hasebe, N.; Kikuchi, J.; Doke, T.

    1988-01-01

    The global distributions of energetic electrons (0.19 - 3.2 MeV) and protons (0.64 - 35 MeV) are shown in the form of contour maps. The data were obtained by two sets of energetic particle telescopes on board the satellite OHZORA. The observed altitude range is 350 - 850 Km. Ten degress meshes in longitude and latitude were used to obtain the intensity contours. A pitch angle distribution of J(α) = J(90). sin n α with n = 5 A is assumed to get the average intensity in each mesh. (author) [pt

  18. Operation of the APEX photoinjector accelerator at 40 MeV

    International Nuclear Information System (INIS)

    Feldman, D.W.; Bender, S.C.; Byrd, D.A.; Carlsten, B.E.; Early, J.W.; Feldman, R.B.; Goldstein, J.C.; Martineau, R.L.; O'Shea, P.G.; Pitcher, E.J.; Schmitt, M.J.; Stein, W.E.; Wilke, M.D.; Zaugg, T.J.

    1992-01-01

    We have successfully operated the photoinjector and rf linear accelerator for the Los Alamos APEX free electron laser (FEL) at design energy, average macropulse current, and emittance. The accelerator, which operates at 1.3 GHz, consists of a 6 MeV photoinjector and three standing-wave structures with a total beam energy of 40 MeV. This paper presents performance characteristics of the APEX system. The results show that this technology is capable of providing reliable, high-peak current, ultra-high brightness electron beams

  19. Attenuation of 10 MeV electron beam energy to achieve low doses does not affect Salmonella spp. inactivation kinetics

    International Nuclear Information System (INIS)

    Hieke, Anne-Sophie Charlotte; Pillai, Suresh D.

    2015-01-01

    The effect of attenuating the energy of a 10 MeV electron beam on Salmonella inactivation kinetics was investigated. No statistically significant differences were observed between the D 10 values of either Salmonella 4,[5],12:i:- or a Salmonella cocktail (S. 4,[5],12:i:-, Salmonella Heidelberg, Salmonella Newport, Salmonella Typhimurium, Salmonella) when irradiated with either a non-attenuated 10 MeV eBeam or an attenuated 10 MeV eBeam (~2.9±0.22 MeV). The results show that attenuating the energy of a 10 MeV eBeam to achieve low doses does not affect the inactivation kinetics of Salmonella spp. when compared to direct 10 MeV eBeam irradiation. - Highlights: • 10 MeV eBeam energy was attenuated to 2.9±0.22 MeV using HDPE sheets. • Attenuation of eBeam energy does not affect the inactivation kinetics of Salmonella. • Microbial inactivation is independent of eBeam energy in the range of 3–10 MeV

  20. Kerma factors and reaction cross sections for n + 12C between 15 and 18 MeV

    International Nuclear Information System (INIS)

    Tornow, W.; Chen, Z.M.; Baird, K.; Walter, R.L.

    1988-01-01

    Differential elastic and inelastic (4.44 MeV) neutron scattering cross sections from 12 C are presented at 15.6, 16.8 and 17.3 MeV. The existing 18.2 MeV differential cross-section data were combined with newly measured analysing power data to parametrise neutron scattering at this energy. The 12 C recoil kerma factors were calculated and reaction cross sections were obtained from a phase-shift analysis and coupled channel analyses in the 15.6-18.2 MeV energy range. (author)

  1. Kerma factors and reaction cross sections for n + /sup 12/C between 15 and 18 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Tornow, W.; Chen, Z.M.; Baird, K.; Walter, R.L.

    1988-07-01

    Differential elastic and inelastic (4.44 MeV) neutron scattering cross sections from /sup 12/C are presented at 15.6, 16.8 and 17.3 MeV. The existing 18.2 MeV differential cross-section data were combined with newly measured analysing power data to parametrise neutron scattering at this energy. The /sup 12/C recoil kerma factors were calculated and reaction cross sections were obtained from a phase-shift analysis and coupled channel analyses in the 15.6-18.2 MeV energy range.

  2. Evidence for detection of 1--10 MeV emission from the Taurus region in 1971 August

    International Nuclear Information System (INIS)

    Gruber, D.E.; Ling, J.C.

    1977-01-01

    The Taurus region was scanned in mid-1971 during three balloon flights with an actively shielded NaI detector sensitive between 0.2 and 10 MeV. Below 1 MeV, these observations yielded measurements and upper limits consistent with extensions of the X-ray power laws of 0.0035 (E/1 MeV) -2 /sup ./ 2 photons (cm 2 s MeV) -1 and 0.0008(E/1 MeV) -2 /sup ./ 1 photons (cm 2 s MeV) -1 for the Crab Nebula and NP 0532, respectively. Above 1 MeV an apparent unpulsed flux, enhanced well above the extrapolated Crab Nebula power law, was observed during the 1971 August 8 flight; it was the most sensitive of the three. For the NP 0532 above 1 MeV on the same date, the measured upper limit of a factor of 8 above the extrapolated power law excludes only the possibility of a large flare-up. The possibility that the observation reported here for 1971 August 8 was a purely instrumental effect, or was produced by environmental radiations, is thoroughly examined, with negative results. If of cosmic origin, the emission must have been short-term (approx.days, months), because other observations in 1973 and 1974 have shown null results. The possibility of variable MeV range emission is discussed in the context of other reported variable emissions in recent years from the Crab and the Taurus region

  3. The evaluation of H total cross section from 20 MeV to 2 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Tingjin, Liu [Chinese Nuclear Data Center, Beijing, BJ (China)

    1996-06-01

    The H total cross section was evaluated in the neutron energy region from 20 to 2000 MeV. The recommended experimental data were fitted by using Spline fit program with knot optimization, the fit values are taken as recommended ones. The data are compared with those from ENDF/B-6 (<100 MeV), the differences are 0.5%{approx}2.0% from 20 to 40 MeV, and almost the same in the energy region 40{approx}100 MeV.

  4. Neutron Energy Spectra from Neutron Induced Fission of 235U at 0.95 MeV and of 238U at 1.35 and 2.02 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Almen, E; Holmqvist, B; Wiedling, T

    1971-09-15

    The shapes of fission neutron spectra are of interest for power reactor calculations. Recently it has been suggested that the neutron induced fission spectrum of 235U may be harder than was earlier assumed. For this reason measurements of the neutron spectra of some fissile isotopes are in progress at our laboratory. This report will present results from studies of the energy spectra of the neutrons emitted in the neutron induced fission of 235U and 238U. The measurements were performed at an incident neutron energy of 0.95 MeV for 235U and at energies of 1.35 and 2.02 MeV for 238U using time-of-flight techniques. The time-of-flight spectra were only analysed at energies higher than those of the incident neutrons and up to about 10 MeV. Corrections for neutron attenuation in the uranium samples were calculated using a Monte Carlo program. The corrected fission neutron spectra were fitted to Maxwellian temperature distributions. For 235U a temperature of 1.27 +- 0.01 MeV gives the best fit to the experimental data and for 238U the corresponding values are 1.29 +- 0.03 MeV at 1.35 MeV and 1.29 +- 0.02 MeV at 2.02 MeV

  5. Neutron-proton elastic scattering between 200 and 500 MeV

    International Nuclear Information System (INIS)

    Clough, A.S.; Gibson, D.R.; Axen, D.

    1979-01-01

    Measurements over an extensive angular range of the Dsub(t) and P parameters in free neutron-proton elastic scattering at laboratory energies of 220, 325, 425 and 495 MeV are reported. Experimental and analytical details are given. (author)

  6. Negative pion-nucleus elastic scattering at 30 and 50 MeV

    International Nuclear Information System (INIS)

    Seth, K.K.; Barlow, D.; Iversen, S.; Kaletka, M.; Nann, H.; Smith, D.; Artuso, M.; Burleson, G.; Blanpied, G.; Daw, G.; Burger, W.J.; Redwine, R.P.; Saghai, B.; Anderson, R.

    1990-01-01

    Differential cross sections for the elastic scattering of 30 and 50 MeV π - by nuclei ranging from 12 C to 208 Pb have been measured using a range spectrometer. Comparison is made with the predictions of a recent optical-model calculation and the general nature of discrepancies is discussed

  7. Smith-Purcell radiation from a 50 MeV beam

    Energy Technology Data Exchange (ETDEWEB)

    Brownell, J.H.; Walsh, J. [Dartmouth Coll., Hanover, NH (United States). Dept. of Physics and Astronomy; Kirk, H.G.; Fernow, R.C. [Brookhaven National Lab., Upton, NY (United States). Dept. of Physics; Robertson, S.H. [Univ. of Colorado, Boulder, CO (United States). Dept. of Astrophysics and Geophysics

    1996-10-01

    A 50 MeV electron beam and a 1 mm period, 5{degree} blaze, echelle grating have been used to produce radiation in the mid-infrared spectral region. The emission is highly collimated and forward-directed. The intensity level in the few ps pulse (2 nJ/sr) indicates a degree of coherent enhancement.

  8. Neutron cross-sections above 20 MeV for design and modeling of ...

    Indian Academy of Sciences (India)

    bination of a high-power, high-energy accelerator, a spallation target for neutron ... The development of the commercial critical reactors of today motivated a large effort on nuclear data up to about 20 MeV, and presently ..... facility in the world.

  9. Therapy by stationary photon fields from a 42 MeV betatron using wedge filters

    International Nuclear Information System (INIS)

    Wicke, L.; Kaercher, K.H.; Naesiger, H.; Prokosch, E.; Vienna Univ.

    1975-01-01

    The dose distribution in photon beams from a 42 MeV betatron using wedge filters of lead with different angles of slope is described. The wedge coefficient to be considered at a field size of 10 x 10 cm is given. The scope for isodoses modified by wedge filters is discussed with regard to stationary-field photon therapy. (orig.) [de

  10. INCLUSIVE SYSTEMATICS FOR SI-28+SI-28 REACTIONS BETWEEN 20 AND 35 MEV PER NUCLEON

    NARCIS (Netherlands)

    BOX, PF; GRIFFIOEN, KA; DECOWSKI, P; BOOTSMA, T; GIERLIK, E; VANNIEUWENHUIZEN, GJ; TWENHOFEL, C; KAMERMANS, R; WILSCHUT, HW; GIORNI, A; MORAND, C; DEMEYER, A; GUINET, D

    Inclusive velocity spectra of heavy ions produced in the Si-28 + Si-28 reaction at 22, 26, 30, and 35 MeV per nucleon were measured and decomposed into peripheral and central components using an analytical moving-source parametrization. The persistence of incomplete fusion followed by evaporation

  11. Software of the System Protection for the PEFP 20MeV Proton Linac

    International Nuclear Information System (INIS)

    Song, Young-Gi; Hong, In-Seok; Cho, Yong-Sub

    2007-01-01

    A 20 MeV proton linear accelerator (linac) has been developed at Proton Engineering Frontier Project (PEFP). A 20 MeV linac consists of 50 keV proton injector, 3 MeV radio frequency quadrupole (RFQ), and 20 MeV drift tube linac (DTL). PEFP control system is developed with several sub-systems (e.g. machine control, diagnostic control, timing control, and interlock systems). These systems have each EPICS based control system which provides a network-based real time distributed control. For stable and harmonic operation, we had developed sequential logic by using state notation language (SNL) and database records with alarm fields for warning signal. The various control system can drop a transmission rate of the control network traffic. We need to manage control signals by a control network gateway and protect values of control servers by security management. In this paper, the stabilization methods of the control signals are described and the results of the stabilized signals are presented

  12. DEPFET detectors for direct detection of MeV dark matter particles

    Energy Technology Data Exchange (ETDEWEB)

    Baehr, A.; Ninkovic, J.; Treis, J. [Max-Planck-Gesellschaft Halbleiterlabor, Munich (Germany); Kluck, H.; Schieck, J. [Institut fuer Hochenergiephysik, Oesterreichische Akademie der Wissenschaften, Vienna (Austria); Atominstitut, Technische Universitaet Wien, Vienna (Austria)

    2017-12-15

    The existence of dark matter is undisputed, while the nature of it is still unknown. Explaining dark matter with the existence of a new unobserved particle is among the most promising possible solutions. Recently dark matter candidates in the MeV mass region received more and more interest. In comparison to the mass region between a few GeV to several TeV, this region is experimentally largely unexplored. We discuss the application of a RNDR DEPFET semiconductor detector for direct searches for dark matter in the MeV mass region. We present the working principle of the RNDR DEPFET devices and review the performance obtained by previously performed prototype measurements. The future potential of the technology as dark matter detector is discussed and the sensitivity for MeV dark matter detection with RNDR DEPFET sensors is presented. Under the assumption of six background events in the region of interest and an exposure of 1 kg year a sensitivity of about anti σ{sub e} = 10{sup -41} cm{sup 2} for dark matter particles with a mass of 10 MeV can be reached. (orig.)

  13. 14.2 MeV neutron induced U-235 fission cross section measurement

    International Nuclear Information System (INIS)

    Li Jingwen; Shen Guanren; Ye Zongyuan; Li Anli; Zhou Shuhua; Sun Zhongfan; Wu Jingxia; Huang Tanzi

    1986-01-01

    The cross section of U-235 fission induced by 14.2 MeV neutrons was measured by the time correlated associated particle method. The result obtained is (2.078+-0.040) barn. Comparison with other author's is also given. (author)

  14. The scattering of polarized deuterons on 3He between 10 and 17 MeV

    International Nuclear Information System (INIS)

    Ohlsen, G.G.; Jarmie, N.; Haglund, R.H. Jr.; Brown, R.E.; Schmelzbach, P.A.

    1978-01-01

    Using the LASL polarized beam facility, the cross section and vector and tensor analysing powers for the 3 He(d vector,d) 3 He and 3 He(d vector,p) 4 He reactions have been measured in a large angular range at energies between 10 and 17 MeV. (orig./WL) [de

  15. High energy proton simulation of 14-MeV neutron damage in Al2O3

    International Nuclear Information System (INIS)

    Muir, D.W.; Bunch, J.M.

    1975-01-01

    High-energy protons are a potentially useful tool for simulating the radiation damage produced by 14-MeV neutrons in CTR materials. A comparison is given of calculations and measurements of the relative damage effectiveness of these two types of radiation in single-crystal Al 2 O 3 . The experiments make use of the prominent absorption band at 206 nm as an index to lattice damage, on the assumption that peak absorption is proportional to the concentration of lattice vacancies. The induced absorption is measured for incident proton energies ranging from 5 to 15 MeV and for 14-MeV neutrons. Recoil-energy spectra are calculated for elastic and inelastic scattering using published angular distributions. Recoil-energy spectra also are calculated for the secondary alpha particles and 12 C nuclei produced by (p,p'α) reactions on 16 O. The recoil spectra are converted to damage-energy spectra and then integrated to yield the damage-energy cross section at each proton energy and for 14 MeV neutrons. A comparison of the calculations with experimental results suggests that damage energy, at least at high energies, is a reasonable criterion for estimating this type of radiation damage. (auth)

  16. Irradiation effects of 11 MeV protons on ferritic steels

    International Nuclear Information System (INIS)

    Hamaguchi, Yoshikazu; Kuwano, Hisashi; Misawa, Toshihei

    1985-01-01

    It is considered that ferritic/martensitic steels are the candidate of the first wall materials for future fusion reactors. The most serious problem in the candidate materials is the loss of ductility due to the elevation of ductile-brittle transition temperature by the high dpa irradiation of neutrons. 14 MeV neutrons produced by D-T reaction cause high dpa damage and also produce large quantity of helium and hydrogen atoms in first wall materials. Those gas atoms also play an important role in the embrittlement of steels. The main purpose of this work was to simulate the behavior of hydrogen produced by the transmutation in the mechanical properties of ferritic steels when they were irradiated with 11 MeV protons. The experimental procedure and the results of hardness, the broadening of x-ray diffraction lines, Moessbauer spectroscopy and small punch test are reported. High energy protons of 10 - 20 MeV are suitable to the simulation experiment of 14 MeV neutron radiation damage. But the production of the active nuclei emitting high energy gamma ray and having long life, Co-56, is the most serious problem. Another difficulty is the control of irradiation temperature. A small irradiation chamber must be developed. (Kako, I.)

  17. Measurements of np scattering at 96 and 162 MeV

    International Nuclear Information System (INIS)

    Olsson, N.; Rahm, J.; Blomgren, J.; Conde, H.; Dangtip, S.; Elmgren, K.; Roennqvist, T.; Zorro, R.; Ringbom, A.; Tibell, G.

    1998-01-01

    This paper presents new, precise measurements of differential cross sections for np scattering at 96 and 162 MeV. The data are steeper at backward angles than most previous data, and point to the classical value for the charged πNN coupling constant. (orig.)

  18. Calculation of neutron cross sections on iron up to 40 MeV

    International Nuclear Information System (INIS)

    Arthur, E.D.; Young, P.G.

    1980-01-01

    The development of high energy d + Li neutron sources for fusion materials radiation damage studies will require neutron cross sections up to 40 MeV. Experimental data above 15 MeV are generally sparse or nonexistent, and reliance must be placed upon nuclear-model calculations to produce the needed cross sections. To satisfy such requirements for the Fusion Materials Irradiation Test Facility (FMIT), neutron cross sections have been calculated for 54 56 Fe between 3 and 40 MeV. These results were joined to the existing ENDF/B-V evaluation below 3 MeV. In this energy range, most neutron reactions can be described using the Hauser-Feshbach statistical model with corrections for preequilibrium and direct-reaction effects. To properly use these models to obtain realistic cross sections, emphasis must be placed upon the determination of suitable input parameters (optical model sets, gamma-ray strength functions, level densities) valid over the energy range of the calculation. To do this, several types of independent data were used to arrive at consistent parameter sets as described

  19. Optimisation of 12 MeV electron beam simulation using variance reduction technique

    International Nuclear Information System (INIS)

    Jayamani, J; Aziz, M Z Abdul; Termizi, N A S Mohd; Kamarulzaman, F N Mohd

    2017-01-01

    Monte Carlo (MC) simulation for electron beam radiotherapy consumes a long computation time. An algorithm called variance reduction technique (VRT) in MC was implemented to speed up this duration. This work focused on optimisation of VRT parameter which refers to electron range rejection and particle history. EGSnrc MC source code was used to simulate (BEAMnrc code) and validate (DOSXYZnrc code) the Siemens Primus linear accelerator model with the non-VRT parameter. The validated MC model simulation was repeated by applying VRT parameter (electron range rejection) that controlled by global electron cut-off energy 1,2 and 5 MeV using 20 × 10 7 particle history. 5 MeV range rejection generated the fastest MC simulation with 50% reduction in computation time compared to non-VRT simulation. Thus, 5 MeV electron range rejection utilized in particle history analysis ranged from 7.5 × 10 7 to 20 × 10 7 . In this study, 5 MeV electron cut-off with 10 × 10 7 particle history, the simulation was four times faster than non-VRT calculation with 1% deviation. Proper understanding and use of VRT can significantly reduce MC electron beam calculation duration at the same time preserving its accuracy. (paper)

  20. Data management design: nucleon-nucleon data bank (0 to 1200 MeV)

    International Nuclear Information System (INIS)

    Signell, P.; Freiheit, F.

    1981-01-01

    This is a guide to the design of the on-line data records in this bank, covering all energies and particle combinations up to about 1200 MeV. The design of the bank's management system satisfies almost all of the conditions set forth in the proposed Design Principles for Physics Data Banks

  1. Design of a 120 MeV $H^{-}$ Linac for CERN High-Intensity Applications

    CERN Document Server

    Gerigk, F

    2002-01-01

    The SPL (Superconducting Proton Linac) study at CERN foresees the construction of a 2.2 GeV linac as a high beam-power driver for applications such as a second-generation radioactive ion beam facility or a neutrino superbeam. At the same time such a high-performance injector would both modernize and improve the LHC injection chain. The 120 MeV normal-conducting section of the SPL could be used directly in a preliminary stage for H- charge-exchange injection into the PS Booster. This would increase the proton flux to the CERN experiments while also improving the quality and reliability of the beams for the LHC. The 120 MeV linac consists of a front-end, a conventional Drift Tube Linac (DTL) to 40 MeV and a Cell Coupled Drift Tube Linac (CCDTL) to the full energy. All the RF structures will operate at 352 MHz, using klystrons and RF equipment recovered from the LEP collider. This paper concentrates on the design of the 3 to 120 MeV section. It introduces the design criteria for high-stability beam optics and th...

  2. POSITRON-ELECTRON DECAY OF SI-28, AT AN EXCITATION-ENERGY OF 50-MEV

    NARCIS (Netherlands)

    BUDA, A; BACELAR, JC; BALANDA, A; VANDERPLOEG, H; SUJKOWSKI, Z; VANDERWOUDE, A

    1993-01-01

    The electron-positron pair decay of Si-28 at 50 MeV excitation produced by the isospin T=0 (alpha + Mg-24) and the mixed isospin T=0,1 (He-3 + Mg-25) reactions has been studied using a special designed Positron-Electron pair spectrometer PEPSI.

  3. Positron-electron decay of 28Si at an excitation energy of 50 MeV

    International Nuclear Information System (INIS)

    Buda, A.; Bacelar, J.C.; Balanda, A.; Ploeg, H. van der; Sujkowski, Z.; Woude, A. van der

    1993-01-01

    The electron-positron pair decay of 28 Si at 50 MeV excitation produced by the isospin T=0 (α+ 24 Mg) and the mixed isospin T=0, 1 ( 3 He+ 25 Mg) reactions has been studied using a special designed Positron-Electron pair spectrometer PEPSI. (orig.)

  4. Dislocation Climb Sources Activated by 1 MeV Electron Irradiation of Copper-Nickel Alloys

    DEFF Research Database (Denmark)

    Barlow, P.; Leffers, Torben

    1977-01-01

    Climb sources emitting dislocation loops are observed in Cu-Ni alloys during irradiation with 1 MeV electrons in a high voltage electron microscope. High source densities are found in alloys containing 5, 10 and 20% Ni, but sources are also observed in alloys containing 1 and 2% Ni. The range of ...

  5. Response of TAPS to monochromatic photons with energies between 45 and 790 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Gabler, A.R. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Doering, W. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Fuchs, M. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Krusche, B. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Metag, V. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Novotny, R. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Roebig-Landau, M. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Stroeher, H. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Tries, V. (II. Physikalisches Institut, Universitaet Giessen, D-35392 Giessen (Germany)); Molenaar, C. (Kernfysisch Versneller Instituut, Groningen (Netherlands)); Loehner, H. (Kernfysisch Versneller Instituut, Groningen (Netherlands)); Van Pol, J.H

    1994-07-15

    The Two Arm Photon Spectrometer TAPS - comprising 384 plastic-BaF[sub 2] scintillator telescopes - was tested with monochromatic photons in the energy range between 45 and 790 MeV. The energy resolution for a collimated photon beam hitting the central detector module was determined to [sigma]/E=0.59%xE[sup -1/2][sub [gamma

  6. 7-MeV electron LINAC based pulse radiolysis facility at RPCD, BARC

    International Nuclear Information System (INIS)

    Naik, C.B.; Nadkarni, S.A.; Toley, M.A.; Shinde, S.J.; Naik, P.D.

    2017-01-01

    7-MeV electron LINAC based pulse radiolysis facility is operational in Chemistry Group of BARC since 1986. The Accelerator is housed in B-132 room in basement of Modular Labs. BARC Accelerator was procured from Radiation Dynamics Inc. UK and its detection system was indigenously developed

  7. Scattering of 30 MeV He3 from Re185

    Science.gov (United States)

    Garrett, P. E.; Phillips, A. A.; Demand, G. A.; Finlay, P.; Green, K. L.; Leach, K. G.; Schumaker, M. A.; Svensson, C. E.; Wong, J.; Hertenberger, R.; Wirth, H.-F.; Faestermann, T.; Krücken, R.; Burke, D. G.; Bettermann, L.; Braun, N.

    2009-01-01

    The scattering of 30 MeV He3 from a Re185 target has been investigated. The measured elastic scattering is in disagreement with calculations using common optical model parameter sets found in the literature. A new optical model parameter set has been determined that reproduces the data for both the elastic and the inelastic scattering channels.

  8. (p,4He) elastic scattering at 350, 650, 1050, and 1150 MeV

    International Nuclear Information System (INIS)

    Aslanides, E.; Brochard, F.; Gorodetzky, P.; Hibou, F.; Lambert, E.

    1977-01-01

    Angular distributions of p- 4 He elastic scattering differential cross sections have been measured at 350, 650, 1050 and 1150 MeV, in regions of four-momentum transfer squared t=0.02-0.71 (GeV/c) 2 . These new measurements confirm the absence of a pronounced first diffraction minimum. New theoretical analyses are also presented. (Auth.)

  9. Theoretical study of cylindrical energy analyzers for MeV range heavy ion beam probes

    International Nuclear Information System (INIS)

    Fujisawa, A.; Hamada, Y.

    1993-07-01

    A cylindrical energy analyzer with drift spaces is shown to have a second order focusing for beam incident angle when the deflection angle is properly chosen. The analyzer has a possibility to be applied to MeV range heavy ion beam probes, and will be also available for accurate particle energy measurements in many other fields. (author)

  10. Review of RBE values of 15 MeV neutrons for effects on normal tissues

    NARCIS (Netherlands)

    Broerse, J.J.

    1974-01-01

    Values of the relative biological effectiveness (RBE) of fast neutrons for effect on normal tissue depend not only on the neutron energy and the dose, but also on the type of tissue irradiated. Values of the RBE of 15 MeV neutrons are reviewed for rapidly proliferating rodent tissue, such as mouse

  11. A measurement of auroral electrons in the 1–10 MeV range

    NARCIS (Netherlands)

    Gils, J.N. van; Beek, H.F. van; Fetter, L.D. de; Hendrickx, R.V.

    Particle fluxes have been measured by means of shielded Geiger-Müller telescopes mounted m a rocket, which was launched from ESRANGE(Kiruna) into a diffuse aurora. The analysis of the dependence of the counting rates on altitude indicates that a weak flux of energetic electrons, 1–10 MeV, has been

  12. Radiological safety research of food irradiation with 7.5 MeV X-rays

    International Nuclear Information System (INIS)

    Yang Bin; Tang Weidong; Zhang Yue; Xu Tao; Jin Jianqiao; Ye Mingyang

    2012-01-01

    China and America both have 7.5 MeV high energy X-ray accelerator. The radiological safety of food irradiated with 7.5 MeV X-rays (bremsstrahlung) has been investigated. Samples of meat and meat ash were located in a large volume of fresh meat at the position of the highest photoneutron fluence and irradiated to an X-ray dose of 15 kGy, twice the maximum dose allowed by the US FDA for meat irradiation. An evaluation of the corresponding radiation exposure from ingestion of the irradiated product has been compared to natural background radiation. The paper concludes that the risk to individuals from intake of food irradiated with X-rays from 7.5 MeV electrons, even with a broad energy spectrum, would be trivial. The common target materials are Au, Ta and W. The U.S, requires only Au and Ta can be used as food irradiation target materials and China has not yet relevant provisions. The first 7.5 MeV accelerator for food irradiation in China is under built, and will do the explore research for the choice of target material. (authors)

  13. Deuteron stripping on beryllium target in the 100-2300 MeV energy range

    International Nuclear Information System (INIS)

    Lecolley, J.F.; Varignon, C.; Durand, D.; Le Brun, C.; Lecolley, F.R.; Lefebvres, F.; Louvel, M.; Thun, J.; Borne, F.; Martinez, E.; Menard, S.; Pras, P.; Boudard, A.; Duchazeaubeneix, J.C.; Durand, J.M.; Frehaut, J.; Hanappe, F.; Ledoux, X.; Legrain, R.; Leray, S.; Milleret, G.; Patin, Y.; Stuttge, L.; Terrien, Y.

    1999-01-01

    Cross sections for stripping and dissociation of deuterons interacting with Be targets in the 100-2300 MeV energy range have been measured. Comparisons with model calculations suggest a dominant contribution of the stripping process. It is also shown that the deuteron break-up cross section exhibits the same energy dependence as the nucleon-nucleon cross section. (orig.)

  14. Positron lifetime studies of 100-MeV oxygen irradiated Pb-doped Bi-2223 superconductors

    NARCIS (Netherlands)

    Banerjee, T.; Viswanath, R.N.; Kanjilal, D.; Kumar, R.; Ramasamy, S.

    2000-01-01

    Positron lifetime studies have been carried out for unirradiated and 100-MeV oxygen ion irradiated Pb-doped Bi-2223 superconductors. The analysis of positron lifetime spectra revealed three lifetime components: a short lifetime, τ1 = 153–196 ps; an intermediate lifetime, τ2 = 269–339 ps; and a long

  15. Neutron leakage spectra from Be, Pb and U spheres at 14 MeV energy

    International Nuclear Information System (INIS)

    Androsenko, A.A.; Androsenko, P.A.; Devkin, B.V.

    1989-01-01

    Experimental data on neutron leakage spectra from beryllium, lead and uranium spheres with a central 14 MeV neutron source using a time-of-flight spectrometer have been measured. The data were compared with those calculated with the BLANK code using different nuclear data files. 15 refs, 1 fig., 2 tabs

  16. Suppression of X-radiation from 2 MeV ion electrostatic accelerator

    International Nuclear Information System (INIS)

    Ignat'ev, I.G.; Miroshnichenko, V.I.; Sirenko, A.M.; Storizhko, V.E.

    2008-01-01

    The paper presents results concerning studies of X-radiation from 2 MeV ion electrostatic accelerator 'Sokol' used for nuclear microprobe analysis. The radiation protection system of the accelerator was developed and tested. Tests of the system of the accelerator show that it reduces doses rate by two orders of magnitude

  17. Measurement of (n,Xn) reaction cross sections at 96 MeV

    International Nuclear Information System (INIS)

    Sagrado Garcia, Melle Inmaculada C.

    2006-10-01

    Nucleon induced reactions in the 20-200 MeV energy range are intensively studied since a long time. The evaporation and the pre-equilibrium processes correspond to an important contribution of the production cross section in these reactions. Several theoretical approaches have been proposed and their predictions must be tested. The experimental results shown in this work are the only complete set of data for the (n,Xn) reactions in this energy range. Neutron double differential cross section measurements using lead and iron targets for an incident neutron beam at 96 MeV were carried out at TSL Laboratory in Uppsala, Sweden. The measurements have been performed for the first time with an energy threshold of 2 MeV and for a wide angular range (15 angle - 98 angle). Neutrons have been detected using two independent setups, DECOI and DEMON and CLODIA and SCANDAL, in order to cover the whole energy range (2-100) MeV. The angular distributions, the differential cross sections and the total inelastic production cross sections have been calculated using the double differential cross sections. The comparison between the experimental data and the predictions given by two of the most popular simulation codes, GEANT3 and MCNPX, have been performed, as well as the comparison with the predictions of the microscopic simulation model DYWAN, selected for its treatment of nucleon-nucleon reactions. (author)

  18. Total neutron cross sections at energies around 20 MeV

    International Nuclear Information System (INIS)

    Morales, J.R.; Romero, J.L.; Martens, P.

    1990-09-01

    The results for measurements of total cross sections on C, Al, Mg, Cu, Ge and Pb at 17.6 and 19.8 MeV are reported. A detailed comparison is presented with previous data and with the global optical model by the Ohio group. We also discuss plans for total non elastic cross section measurements. 31 refs, 12 figs, 2 tabs

  19. Development of neutron-monitor detectors applicable for energies up to 100 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Tatsuhiko; Endo, Akira; Yamaguchi, Yasuhiro; Kim, Eunjoo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nakamura, Takashi [Tohoku Univ., Sendai, Miyagi (Japan)

    2003-03-01

    For the purpose of monitoring of neutron doses in high energy accelerator facilities, we have been developing neutron detectors which are applicable for neutron energies up to 100 MeV. The present paper reports characteristics of a phoswitch-type neutron detector which is composed of a liquid organic scintillator and {sup 6}Li+ZnS(Ag) sheets. (author)

  20. Study of inclusive proton spectra from 20 MeV deuteron breakup by bismuth

    International Nuclear Information System (INIS)

    Badiger, N.M.; Hallur, B.R.; Madhusoodhanan, T.; Sathyavathiamma, M.P.; Puttaswamy, N.G.; Darshan, V.P.; Sharma, H.; Chintalapudi, S.N.

    1997-01-01

    The breakup of deuteron into proton and neutron has been studied earlier to understand the breakup mechanism. Inclusive measurements show the expected broad bumps near the beam velocity. In the present experiment, the breakup of 20 MeV deuterons by bismuth target has been investigated

  1. Electron-positron collision physics: 1 MeV to 2 TeV

    International Nuclear Information System (INIS)

    Perl, M.L.

    1988-07-01

    An overview of electron-positron collision physics is presented. It begins at 1 MeV, the energy region of positronium formation, and extends to 2 TeV, the energy region which requires an electron- positron linear collider. In addition, the concept of searching for a lepton-specific forces is discussed. 18 refs., 15 figs., 1 tab

  2. Status of the 160 MeV H- Injection into the CERN PSB

    CERN Document Server

    Weterings, W; Benedetto, E; Borburgh, J; Bracco, C; Carli, C; Goddard, B; Hanke, K; Mikulec, B; Newborough, A; Noulibos, R; Tan, J

    2012-01-01

    The 160 MeV H- beam from the LINAC4 will be injected into the 4 superimposed rings of the PS Booster (PSB) with a new H- charge-exchange injection system. This entails a massive upgrade of the injection region. The hardware requirements and constraints, the performance specifications and the design of the H- injection region are described.

  3. Physics design of a 70 MeV high intensity cyclotron, CYCIAE-70

    International Nuclear Information System (INIS)

    Zhang Tianjue; An Shizhong; Wang Chuan; Yin Zhiguo; Wei Sumin; Li Ming; Yang Jianjun; Ji Bin; Jia Xianlu; Zhong Junqing; Yang Fang

    2011-01-01

    This paper introduces the physics design of a 70 MeV high intensity cyclotron at China Institute of Atomic Energy (CIAE), which is aimed for multiple uses including radioactive ion-beam (RIB) production. The machine adopts a compact structure of four straight sectors, capable of accelerating two kinds of beams, i.e. H − and D − . The proton and deuteron beam will be extracted in dual opposite directions by charge exchange stripping devices. The energy of the extracted proton beam is in the range 35–70 MeV with an intensity up to 700 μA. The corresponding values for the deuteron beam are 18–33 MeV and 40 μA. This paper will present the main characteristics and parameters in the design of the 70 MeV cyclotron, the results of the basic beam dynamics study, as well as the physics in the design of the different systems, including the main magnet, RF, injection and extraction systems, etc.

  4. Energy distribution of 0. 279 MeV gamma rays Compton scattered from bound electrons

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B; Singh, P; Singh, G; Ghumman, B S

    1984-11-01

    Energy and intensity distribution of 0.279 MeV gamma rays Compton scattered from K-shell electrons of tantalum is measured at scattering angle of 70deg. The experimental results are compared with the available theoretical data. Spectral distribution is also obtained as a function of scatterer thickness to account for the contribution of false events. 13 refs.

  5. NUSTAR, SWIFT, and GROND Observations of the Flaring MEV Blazar PMN J0641-0320

    DEFF Research Database (Denmark)

    Ajello, M.; Ghisellini, G.; Paliya, V. S.

    2016-01-01

    Area Telescope and subsequent follow-up observations with NuSTAR, Swift, and GROND of a new member of the MeV blazar family: PMN J0641-0320. Our optical spectroscopy provides confirmation that this is a flat-spectrum radio quasar located at a redshift of z = 1.196. Its very hard NuSTAR spectrum (power...

  6. Measurements and amplitude analysis of small angle pp polarization between 398 and 572 MeV

    CERN Document Server

    Aebischer, D; Greeniaus, L G; Hess, R; Junod, A; Lechanoine-Leluc, C; Nikles, J C; Rapin, D; Werren, D W

    1976-01-01

    Results are reported of an experiment performed at CERN in which a 38% polarized beam of protons was scattered on a carbon target and the measurements were made at 398, 455, 530 and 572 MeV in the CM angular range 4 degrees < Theta *<22 degrees . It is shown that the data are in good agreement with phase shift analysis predictions. (7 refs).

  7. The 270 MeV deuteron beam polarimeter at the Nuclotron Internal Target Station

    Energy Technology Data Exchange (ETDEWEB)

    Kurilkin, P.K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Ladygin, V.P., E-mail: vladygin@jinr.ru [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Uesaka, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Suda, K. [RIKEN Nishina Center, Saitama (Japan); Gurchin, Yu.V.; Isupov, A.Yu. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Itoh, K. [Department of Physics, Saitama University, Saitama (Japan); Janek, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Physics Department, University of Zilina, 010 26 Zilina (Slovakia); Karachuk, J.-T. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Advanced Research Institute for Electrical Engineering, Bucharest (Romania); Kawabata, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Khrenov, A.N.; Kiselev, A.S.; Kizka, V.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kliman, J. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia); Krasnov, V.A.; Livanov, A.N. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Institute for Nuclear Research, Moscow (Russian Federation); Maeda, Y. [Kyushi University, Hakozaki (Japan); Malakhov, A.I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Matousek, V.; Morhach, M. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia)

    2011-06-21

    A deuteron beam polarimeter has been constructed at the Internal Target Station at the Nuclotron of JINR. The polarimeter is based on spin-asymmetry measurements in the d-p elastic scattering at large angles and the deuteron kinetic energy of 270 MeV. It allows to measure vector and tensor components of the deuteron beam polarization simultaneously.

  8. 12 MeV, 4.3 kW electron linear accelerator irradiation application

    International Nuclear Information System (INIS)

    Hang Desheng; Lai Qiji

    2000-01-01

    Characteristics of an electron linear accelerator, which has 6-12 MeV energy, 4.2 kW average beam power is introduced. Results show that it has advantages on improving the characteristics of semiconductor devices such as diodes, triodes, SCR, preventing garlic from sprout, preservation of food, and so on

  9. Progress report on the 14-MeV fission cross section measurements

    International Nuclear Information System (INIS)

    1979-01-01

    The development of a recoil proton monitor was completed. It will be used to measure the neutron flux in the 14-MeV fisson cross section measurements. Extensive calculations of the efficiency of this monitor were made and compared with the calculations of other authors. It is clear that a major source of uncertainty in the efficiency is the lack of precise knowledge of the angular distribution of the n-p elastic scattering cross section. This leads to a change in efficiency of 3% depending on the form of the angular distribution that is used. A 4πβ-γ coincidence system was assembled to investigate the K-correction in determining the absolute activity of foil sources. Iron foils will be used as secondary flux standards in comparing the 14-MeV neutron flux with the fluxes in other laboratories, so this is an important correction to measure. The target and target holders that will be used in the 14-MeV measurements were designed and constructed. Preparations were completed to measure the angular distribution of the fission fragments produced in neutron-induced fission at 14 MeV. 2 figures

  10. The neutron-deuteron elastic scattering angular distribution at 95 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Mermod, Philippe

    2004-04-01

    The neutron-deuteron elastic scattering differential cross section has been measured at 95 MeV incident neutron energy, with the Medley setup at TSL in Uppsala. The neutron-proton differential cross section has also been measured for normalization purposes. The data are compared with theoretical calculations to investigate the role of three-nucleon force effects.

  11. CHARACTERIZATION OF 27 MEV PROTON BEAM GENERATED BY TOP-IMPLART LINEAR ACCELERATOR.

    Science.gov (United States)

    De Angelis, C; Ampollini, A; Basile, E; Cisbani, E; Della Monaca, S; Ghio, F; Montereali, R M; Picardi, L; Piccinini, M; Placido, C; Ronsivalle, C; Soriani, A; Strigari, L; Trinca, E; Vadrucci, M

    2018-01-29

    The first proton linear accelerator for tumor therapy based on an actively scanned beam up to the energy of 150 MeV, is under development and construction by ENEA-Frascati, ISS and IFO, under the Italian TOP-IMPLART project. Protons up to the energy of 7 MeV are generated by a customized commercial injector operating at 425 MHz; currently three accelerating modules allow proton delivery with energy up to 27 MeV. Beam homogeneity and reproducibility were studied using a 2D ionizing chamber, EBT3 films, a silicon diode, MOSFETs, LiF crystals and alanine dosimetry systems. Measurements were taken in air with the detectors at ~1 m from the beam line exit window. The maximum energy impinging on the detectors surface was 24.1 MeV, an energy suitable for radiobiological studies. Results showed beam reproducibility within 5% and homogeneity within 4%, on a circular surface of 16 mm in diameter. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. A Faraday Cup with high frequency response for a 200 MeV LINAC proton beam

    International Nuclear Information System (INIS)

    Zucker, M.S.; Bittner, J.W.

    1991-01-01

    The purpose of this device, composed essentially of coaxial line elements, is monitoring, on a per micropulse basis, the beam intensity of a 200 MeV LINAC at the BNL Radiation Effects Facility. The center conductor of the coaxial line acts as a beam stop. The output pulses are suitable for fast timing. 2 refs., 5 figs

  13. A standard 9MeV γ beam for detector calibration

    International Nuclear Information System (INIS)

    Troesch-Lasseur, G.; Bermann, F.; Gaulard, M.

    1975-01-01

    A γ capture irradiation device with beam extraction is being developed at Triton. The mean energy in the beam is 9MeV. The beam intensity has been determined from absorbed dose measurements according to ICRU specifications. The maximum dose rate taken as calibration standard is 125+-9rad/h [fr

  14. Smith-Purcell radiation from a 50 MeV beam

    International Nuclear Information System (INIS)

    Brownell, J.H.; Walsh, J.; Kirk, H.G.; Fernow, R.C.; Robertson, S.H.

    1996-10-01

    A 50 MeV electron beam and a 1 mm period, 5 degree blaze, echelle grating have been used to produce radiation in the mid-infrared spectral region. The emission is highly collimated and forward-directed. The intensity level in the few ps pulse (2 nJ/sr) indicates a degree of coherent enhancement

  15. Positronium formation in helium bubbles in 600 MeV proton-irradiated aluminium

    DEFF Research Database (Denmark)

    Jensen, K. O.; Eldrup, Morten Mostgaard; Singh, Bachu Narain

    1985-01-01

    Aluminium samples containing helium bubbles produced by 600 MeV proton irradiation at 430°C were investigated by positron annihilation; both lifetime and angular correlation measurements were made. The angular correlation curves contain an unusually narrow component. This component is associated...

  16. Evaluated Nuclear Data Library for Transport Calculations at Energies up to 150 MeV

    International Nuclear Information System (INIS)

    Korovin, Yu.A.; Konobeyev, A.Yu.; Pilnov, G.B.; Stankovskiy, A.Yu.

    2005-01-01

    A new evaluated nuclear data library has been created. The library consists of two sub-libraries for neutron and proton incident particles. The first version of neutron sub-library has been completed and described in the present paper. The library contains nuclear data for transport, heating, and shielding applications for 242 nuclides ranging in atomic number from 8 to 82 in the energy region of primary neutrons from 10-5 eV to 150 MeV. Data below 20 MeV are taken mainly from ENDF/B-VI (Revision 8) and for some nuclides, from the JENDL-3.3 and JEFF-3.0 libraries. The evaluation of emitted particle energy and angular distributions at the energies above 20 MeV was performed with the help of the ALICE/ASH code and the analysis of available experimental data. The total cross sections, elastic cross sections, and elastic scattering angular distributions were calculated with the help of the coupled channel model. The results of the calculation were adjusted to the data from ENDF/B-VI, JENDL-3.3m or JEFF-3.0 at the neutron energy equal to 20 MeV. The library is written in ENDF/B-VI format using the MF=3/MT=5 and MF=6/MT=5 representations

  17. Postirradiation tensile properties of Mo and Mo alloys irradiated with 600 MeV protons

    International Nuclear Information System (INIS)

    Mueller, G.V.; Gavillet, D.; Victoria, M.; Martin, J.L.

    1994-01-01

    Tensile specimens of pure Mo and Mo-5 Re, Mo-41 Re and TZM alloys have been irradiated with 600 MeV protons in the PIREX facility at 300 and 660 K to 0.5 dpa. Results of the postirradiation tensile testing show a strong radiation hardening and a severe loss of ductility for all the materials tested at room temperature. ((orig.))

  18. Physics design of a 10 MeV, 6 kW travelling wave electron linac

    Indian Academy of Sciences (India)

    We present the physics design of a 10 MeV, 6 kW S-band (2856 MHz) electron linear accelerator (linac), which has been recently built and successfully operated at Raja Ramanna Centre for Advanced Technology, Indore. The accelerating structure is a 2 π / 3 mode constant impedance travelling wave structure, which ...

  19. Integral cross sections for π+p scattering between 52 and 126 MeV

    International Nuclear Information System (INIS)

    Friedman, E.; Goldring, A.; Wagner, G.J.; Altman, A.; Johnson, R.R.; Meirav, O.; Hanna, M.; Jennings, B.K.

    1989-06-01

    Integral cross-sections for the elastic scattering of π + on p from 20 degrees and 30 degrees to 180 degrees were measured at seven energies between 52 and 126 MeV. These integrals are found to be in good agreement with predictions made with currently accepted phase-shifts. (Author) 15 refs., tab., 2 figs

  20. The development of a spectrometer for 14 MeV neutrons from fusion

    International Nuclear Information System (INIS)

    Aronsson, D.

    1991-01-01

    A spectrometer for 14 MeV neutrons, to be used for fusion plasma diagnostics at JET, was developed. The spectrometer utilizes neutron scattering in a polyethylene foil with the detection of the scattered neutron and its associated recoil proton. For the detection of 12 MeV protons we have tested silicon surface barrier detectors, lithium-drifted silicon detectors and high purity germanium detectors. The lithium-drifted detectors were finally selected for use in the spectrometer. The lithium-drifted silicon diodes have also been used for direct spectrometry, utilizing the neutron induced charged particle reactions in silicon. The methods used for the energy calibration and the timing calibration of the diodes, both during the installation of the spectrometer and during operation, are described. The detection of 2 MeV neutrons is done by fast plastic scintillators. Since the neutron generator which was used to test the detectors supplies 14 MeV or 2.5 MeV neutrons only, a neutron energy converter has to be constructed to study the detectors at other neutron energies. In the actual spectrometer an array of scintillation neutron detectors is used. A method of calibrating such an array of detectors with a gamma source was elaborated and is also described here. The result of the calibration is a set of parameters than can be used to determine the high voltage settings and the discriminator levels that are needed to achieve homogeneous sensitivity for all the detectors of the array. The energy scale itself was then calibrated by using gamma sources of various energies. To test the spectrometer as a whole at a neutron generator, a test bed was constructed. A lithium-drifted silicon diode was used to measure the neutron flux and the neutron energy resolution in the test bed. (au)

  1. Elastic scattering of 16O on 28Si between 45.0 and 73.5 MeV

    International Nuclear Information System (INIS)

    Shkolnik, V.; Dehnhard, D.; Kubono, S.; Franey, M.A.; Tripp, S.; Artz, J.L.; Weber, D.J.

    1977-01-01

    Angular distributions of 16 O elastically scattering by Si isotopes were analyzed by the optical model. Differential cross sections are shown for all isotopes at 60 MeV, and for 28 Si at energies from 45 to 63 MeV. The potentials found are discussed in some detail; the best fits were produced by surface-transparent potentials. 3 figures, 2 tables

  2. The 16 MeV - microtron at the Institute for Physics and Technology of Radiation Devices and its application

    International Nuclear Information System (INIS)

    Catana, D.; Panaitescu, I.; Axinescu, S.; Minea, R.

    1992-01-01

    The 17-orbit microtron at the Institute for Physics and Technology of Radiation Devices, Bucharest is described. The energy of electrons is 11 MeV in the first accelerating mode and 16 MeV in the second accelerating mode with a pulse beam power of about 400 Kw and a duty ratio of 10 -3 . (Author)

  3. Investigation of the reaction 35Cl(τ, α)34Cl at Eτ = 15 MeV

    NARCIS (Netherlands)

    Gasteren, J.J.M. van; Sikora, B.; Steld, A. van der

    1974-01-01

    The 35Cl(τ, α)34C reaction has been used to study the properties of 34Cl levels up to an excitation energy of 5 MeV. Angular distributions of 37 levels were measured with a split-pole magnetic spectrograph, at a bombarding energy of 15 MeV. New levels have been found at 3847, 3964, 4206, 4321 and

  4. Application of multi-step direct reaction theory to 14 MeV neutron reaction, 3 (n,. cap alpha. )

    Energy Technology Data Exchange (ETDEWEB)

    Kumabe, I.; Matoba, M.; Fukuda, K. [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering; Ikegami, H.; Muraoka, M [eds.

    1980-01-01

    Multi-step direct-reaction theory proposed by Tamura et al. has been applied to continuous spectra of the 14 MeV (n, ..cap alpha..) reaction with some modifications. Calculated results reproduce well the experimental energy and angular distributions of the 14 MeV (n, ..cap alpha..) reactions.

  5. Research of Dic process induced by 92 MeV and 77 MeV /sup 14/N and /sup 27/Al

    Energy Technology Data Exchange (ETDEWEB)

    Zhong-yan, Guo; Wen-qing, Shen; Yong-tai, Zhu; Wei-min, Qiao; Shu-zhi, Yin; Wen-long, Zhang; En-jiu, Wu

    1987-07-01

    The projectile-like fragments of /sup 14/N+/sup 27/Al reaction (E/sub Lab/ = 93 and 77 MeV) were measured by using the large area position sensitive ionization chamber. The contour plots of d/sup 3/ sigma/d..cap omega..dEdZ in TKE-theta plane, angle distributions integrating over different TKEL window, the Z-distribution and angle distribution of different fragments from Li to Na were obtained. Variations of sigmaz/sup 2/, tau with TKEL were deduced. A brief discussion of the experimental results was given also.

  6. Comparison of 4.2 MeV Fe+ and 46.5 MeV Ni6+ ion irradiation for the study of void swelling

    International Nuclear Information System (INIS)

    Blamires, N.G.; Worth, J.H.

    1975-11-01

    Void formation in pure nickel and 316 steel containing 10 ppm He has been studied using 4.2 MeV Fe+ ions from the Harwell Van de Graaff accelerator. The dose dependence of swelling in nickel at 525degC and the dose and temperature dependence of swelling in 316 steel is reported. The results are compared with those of other workers, especially those sup(13,14) using 46.5 MeV Ni 6+ ions. In general, there is good agment, except for a marked decrease in swelling of 316 steel at 650degC and 700degC compared with the Ni 6+ bombardment. The reason for this is thought to result from the restricted width of the damaged region in the low energy case which at the high temperatures is comparable with the inter-void spacing. Anomalous void distributions adjacent to grain boundaries are reported and are probably caused by grain boundary movement. Denuded zones at grain boundaries in 316 steel vary in width from approximatly 1300A at 450degC to approximatly 8800A at 700degC. The region adjacent to the surface of the nickel specimens exhibits an abnormally high swelling. Possible explanations are suggested

  7. Simulation study of neutron production in thick beryllium targets by 35 MeV and 50.5 MeV proton beams

    Science.gov (United States)

    Shin, Jae Won; Park, Tae-Sun

    2017-09-01

    A data-driven nuclear model dedicated to an accurate description of neutron productions in beryllium targets bombarded by proton beams is developed as a custom development that can be used as an add-on to GEANT4 code. The developed model, G4Data(Endf7.1), takes as inputs the total and differential cross section data of ENDF/B-VII.1 for not only the charge-exchange 9Be(p,n)9B reaction which produces discrete neutrons but also the nuclear reactions relevant for the production of continuum neutrons such as 9Be(p,pn)8Be and 9Be(p,n α) 5Li . In our benchmarking simulations for two experiments with 35 MeV and 50.5 MeV proton beams impinged on 1.16 and 1.05 cm thick beryllium targets, respectively, we find that the G4Data(Endf7.1) model can reproduce both the total amounts and the spectral shapes of the measured neutron yield data in a satisfactory manner, while all the considered hadronic models of GEANT4 cannot.

  8. (γ,n) reaction in nuclei of the 12<=A<=238 interval in the intermediate energy region (300 MeV-1000MeV)

    International Nuclear Information System (INIS)

    Martins, J.B.

    1974-01-01

    The absolute cross section of the 12 C(γ,n) 11 C, 19 F(γ,n) 18 F, 23 Na(γ,n) 22 Na, 31 P(γ,n) 30 P, 52 Cr(γ,n) 51 Cr, 55 Mn(γ,n) 54 Mn, 59 Co(γ,n) 58 Co, 75 As(γ,n) 74 As, 103 Rh(γn) 102 Rh, 127 I(γ,n) 126 I, 197 Au(γ,n) 196 Au and 238 U(γ,n) 237 U reactions were determined, experimentally, in the energy range from 300 MeV to 1000 MeV, using Bremsstrahlung photons. The measured cross sections were compared with results estimated by Monte Carlo Method applied to intranuclear cascades initiated by phothons. A functional dependence between the average value of (γ,n) absolute cross section and the mass number, were established. The (γ,n) absolute cross sections from simple relations, which transparencies of complexe nuclei for mesons and nucleons photo produced were also determined. (M.C.K.) [pt

  9. Kerma factors for neutrons of 14 MeV to 60 MeV in elemental H, C, N and O

    Energy Technology Data Exchange (ETDEWEB)

    Behrooz, M.A.; Watt, D.E. (Dundee Univ. (UK). Dept. of Medical Biophysics)

    1981-01-01

    Total kerma factors, and partial kerma factors for production of specified charged H and He particles and heavier recoils, have been computed using basic theoretical and experimental nuclear data for neutrons at energies between 14 MeV and 60 MeV in the main tissue elements and in ICRU muscle tissue. All the more recent computations of total kerma factors, along with those determined from direct experimental measurements of partial kerma factors, now form a reasonably consistent set of data enabling average total kerma factors with coefficients of better than 3% for hydrogen, 16% for carbon, 23% for nitrogen and 9% for oxygen to be recommended for application to medical dosimetry and radiation protection. Total kerma factors for ICRU muscle tissue have a precision of better than 2.5% over the neutron energy range considered. Although there is adequate precision for total kerma factors for soft tissue, nevertheless analysis of the partial kerma factors indicates that caution must be exercised in use of the information for quality specification, e.g. in microdose spectra, and that more detailed basic reaction data is required for fast neutrons.

  10. The quasi-monochromatic photon beam used in photoneutron experiments from 20-120 MeV at the 600 MeV Saclay Linac

    International Nuclear Information System (INIS)

    Veyssiere, A.; Beil, H.; Bergere, R.; Carlos, P.; Fagot, J.; Lepretre, A.; Ahrens, J.

    1979-01-01

    A beam of 20-130 MeV positrons, with average intensities between 10 nA and 50 nA, is used at the 600 MeV Saclay Linac to create a quasi-monochromatic photon beam with a continuously variable energy. This beam was used to measure photoneutron cross sections and the corresponding photonuclear facility is first described. The computer-controlled methods, implemented to measure the energy spectrum and the emittance of the positron beam are described. The quasi-monochromatic photon lines are produced by the annihilation in flight of monoenergetic positrons in two annihilation radiators with different Z successively. The photon beam emission angle theta is shown to be the most critical parameter in the search for an optimum overall signal to background ratio for a specific photoneutron experiment. The choice of an angle theta approximately 4 0 is explained for absolute measurements of sigma(γ, xn) cross-sections, for which the used average intensities of monochromatic photons were thus purposely reduced to approximately 5 X 10 3 s -1 , with an energy resolution approximately 12%. (Auth.)

  11. Experimental and calculated effectiveness of a radiochromic dye film to stopping 21 MeV 7Li and 64 MeV 16O ions

    International Nuclear Information System (INIS)

    Olsen, K.J.; Hansen, J.W.

    1984-01-01

    Relative radiation effectiveness, RE, of 21 MeV 7 Li and 64 MeV 16 O ions being completely stopped in a tissue equivalent film dose meter has been measured as a function of penetration depth and energy, and the results have been compared with calculations based on a delta-ray theory for heavy charged particles developed by Katz et al. The experiment was designed to test calculations particularly in the Bragg-peak region of the slowing down particles where significant deviation between theory and experiment was found. Fitting of the characteristic D 37 dose and the size of the radiation sensitive element in the detector, which are important parameters in the theoretical model, does not improve the overall correlation between theory and experiment. It is concluded that disagreement between theoretical and experimental RE-values below 1.5 MeV/amu is partly due to lack of equivalence between the delta-ray spectrum and the slowing down spectrum of electrons from low-LET radiation, and partly from approximations in the calculated distribution of energy deposition of the delta-rays. (orig.)

  12. Spin excitations in 48Ca and 90Zr with 319 MeV protons

    International Nuclear Information System (INIS)

    Nanda, S.K.

    1985-05-01

    Cross sections, analyzing powers, and spin-flip probabilities have been measured in the low momentum transfer region in the 90 Zr(p vector, p' vector) 90 Zr* reaction at 319 MeV. A rich fine structure is observed for the first time in inelastic proton scattering in the previously proposed M1 giant resonance region. Angular distribution of most of these states are consistent with M1 excitation. The excitation energies of the fine structure states are in good agreement with similar structure seen in electron scattering; however, discrepancies in spin assignments remain. The measured cross section for the entire bump is about 37 +- 10% of the Distorted Wave Impulse Approximation (DWIA) prediction for the M1 strength in 90 Zr with simple wave functions. However, an analysis of the fine structure states reveals about 15% of the strength in the M1 region to be due to narrow El states; another 8% is attributed to M2 strength. The spin-flip measurements for 90 Zr reveal a large spin-flip probability value for the M1 region; good agreement is obtained with DWIA calculations. However, a large cross section for spin excitations distributed uniformly over the excitation energy region from about 7 to 25 MeV is observed for the first time. The spin excitation strength in this giant resonance continuum is found to about 0.80 mb/sr/MeV. Angular distributions for the spin-flip cross sections from 7 to 18 MeV in steps of 2 MeV have been analyzed with low multipole spin excitation calculations in the DWIA framework; the observed spin-flip strength in this region is found to be consistent with spin excitation involving angular momentum transfer of up to two. Finally, cross section, analyzing power, and spin-flip probability data have also been obtained for the 10.23 MeV M1 transition in the 48 Ca(p vector, p' vector) 48 Ca* reaction at 319 MeV. The quenching of M1 strength in 48 Ca relative to theoretical predictions is found to be consistent with previous work

  13. Measurement of neutron-induced fission cross-sections of Th232, U238, U233 and Np237 relative to U235 from 1 MeV to 200 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Shcherbakov, O.A.; Laptev, A.B.; Petrov, G.A. [Petersburg Nuclear Physics Inst., Gatchina, Leningrad district (Russian Federation); Fomichev, A.V.; Donets, A.Y.; Osetrov, O.I.

    1998-11-01

    The measurements of neutron-induced cross-section ratios for Th232, U238, U233 and Np237 relative to U235 have been carried out in the energy range from 1 MeV up to 200 MeV using the neutron time-of-flight spectrometer GNEIS based on 1 GeV proton synchrocyclotron. Below 20 MeV, the results of present measurements are roughly in agreement with evaluated data though there are some discrepances to be resolved. (author)

  14. Contrast of dry and water-saturated arabidopsis seeds irradiated by MeV energy ions

    International Nuclear Information System (INIS)

    Mei Tao; Qin Huaili; Xue Jianming; Wang Yugang

    2007-01-01

    The dry and water-saturated seeds of Arabidopsis thaliana were irradiated by H + ions with 6.5 MeV in atmosphere. The ion fluence used in this experiment was in the range of 4 x 10 9 -1 x 10 14 ions/cm 2 . According to the structure of the seed and TRIM simulation, the ions with the energy of 6.5 MeV can penetrate the whole seed. The experiment shows that the fluence-response curves for the dry seeds and water-saturated seeds had distinct shoulders and reduced rapidly. The experimental results show that the water-imbibed seeds were more sensitive than the dry seeds and the reason is from free radicals reaction. A model has been constructed, and primely simulates the experiment data. (authors)

  15. Gamma-ray emission spectra from spheres with 14 MeV neutron source

    International Nuclear Information System (INIS)

    Yamamoto, Junji; Kanaoka, Takeshi; Murata, Isao; Takahashi, Akito; Sumita, Kenji

    1989-01-01

    Energy spectra of neutron-induced gamma-rays emitted from spherical samples were measured using a 14 MeV neutron source. The samples in use were LiF, Teflon:(CF 2 ) n , Si, Cr, Mn, Co, Cu, Nb, Mo, W and Pb. A diameter of the sphere was either 40 or 60 cm. The gamma-ray energy in the emission spectra covered the range from 500 keV to 10 MeV. Measured spectra were compared with transport calculations using the nuclear data files of JENDL-3T and ENDF/B-IV. The agreements between the measurements and the JENDL-3T calculations were good in the emission spectra for the low energy gamma-rays from inelastic scattering. (author)

  16. Evaluation of neutron cross sections to 40 MeV for 5456Fe

    International Nuclear Information System (INIS)

    Arthur, E.D.; Young, P.G.

    1980-01-01

    Cross sections for neutron-induced reactions on 54 56 Fe were calculated by employing several nuclear models: optical, Hauser-Feshbach, preequilibrium and DWBA - in the energy range between 3 and 40 MeV. As a prelude to the calculations, the necessary input parameters were determined or verified through analysis of a large body of experimental data for both neutron- and proton-induced reactions in this mass and energy region. This technique also led to cross sections in which the simultaneous influence of available data types added to their consistency and reliability. Calculated cross sections as well as neutron and gamma-ray emission spectra were incorporated into an ENDF evaluation suitable for use to 40 MeV. 12 figures, 1 table

  17. I=0, C=-1 mesons from 1940 to 2410 MeV

    CERN Document Server

    Anisovich, A.V.; Batty, C.J.; Bugg, D.V.; Montanet, L.; Nikonov, V.A.; Sarantsev, A.V.; Sarantsev, V.V.; Zou, B.S.

    2011-01-01

    New Crystal Barrel data are reported for pbar-p -> omega-eta and pbar-p -> omega-pizero-pizero with omega decaying to piplus-piminus-pizero. The omega-eta data confirm angular distributions obtained earlier from data where omega -> pizero-gamma. The new omega-eta data provide accurate measurements of vector and tensor polarisations of the omega and lead to considerable improvements in masses and widths of s-channel resonances. A new J^PC = 3^+- I = 0 resonance is observed with mass M = 2025+-20 MeV and width Gamma = 145+-30 MeV. Polarisation is close to zero everywhere and tensor polarisations are large, as is the case also for pbar-p -> omega-pizero.

  18. Measurement of the polarization correlation coefficient in elastic pp scattering at 610 MeV

    International Nuclear Information System (INIS)

    Borisov, N.S.; Glonti, L.N.; Kazarinov, M.Yu.

    1977-01-01

    The polarization correlation coefficient Csub(nn) for elastic pp scattering at 610+-10 MeV was measured for four scattering angles: 40, 67, 78 and 90 deg (c.m.s.). A polarized proton beam with a maximum polarization of 0.39+-0.02 and a polarized proton target of the frozen type were used. The maximum polarization of the target was 0.97+-0.04. The experimental procedure is described in detail. The Csub(nn) measured are compared with the results of a phase analysis and the findings at 575 MeV obtained elsewhere. The Csub(nn) coefficients are shown to be valuable to discriminate alternative solutions of the phase analysis. The polarized proton targets of the frozen type, no accounting the complexity of their design, are emphasized to be rather reliable and convenient devices for conducting experiments at accelerators

  19. Scattering of 14.2 MeV polarized neutrons from 12C

    International Nuclear Information System (INIS)

    Casparis, R.; Leemann, B.Th.; Preiswerk, M.; Rudin, H.; Wagner, R.; Zupranski, P.

    1976-01-01

    Polarized 14.2 MeV neutrons with a polarization of approximately 50% were produced in the 3 H(d(pol),n(pol)) 4 He reaction using vector polarized deuterons from an 'atomic beam' source of polarized ions. The angular distributions of the analyzing power in the elastic and inelastic (Q = -4.43 MeV) scattering of neutrons from carbon have been measured at ten angles in the range from 22 0 to 152 0 c.m. A time-of-flight technique was used to separate elastically and inelastically scattered neutrons. The results have been compared with theoretical calculations obtained with the DWBA and the coupled channels method. (Auth.)

  20. Beam dynamics studies of a 30 MeV RF linac for neutron production

    Science.gov (United States)

    Nayak, B.; Krishnagopal, S.; Acharya, S.

    2018-02-01

    Design of a 30 MeV, 10 Amp RF linac as neutron source has been carried out by means of ASTRA simulation code. Here we discuss details of design simulations for three different cases i.e Thermionic , DC and RF photocathode guns and compare them as injectors to a 30 MeV RF linac for n-ToF production. A detailed study on choice of input parameters of the beam from point of view of transmission efficiency and beam quality at the output have been described. We found that thermionic gun isn't suitable for this application. Both DC and RF photocathode gun can be used. RF photocathode gun would be of better performance.

  1. Construction of 100 MeV electron linac in Kyoto University

    International Nuclear Information System (INIS)

    Shirai, Toshiyuki; Sugimura, Takeshi; Kando, Masaki

    1995-01-01

    An electron linear accelerator and a compact storage ring have been constructed at Kyoto University. The beam energy of the storage ring is 300 MeV and will be utilized as a synchrotron radiation source. The output beam energy of the linac is 100 MeV and the designed beam current is 100 mA at the pulse width of 1 μsec. The construction of the linac had been finished and the test is under going. The electron beam of 300 mA is extracted from the electron gun and the peak RF power of 20 MW is successfully fed to the accelerating structures at the pulse width of 2 μsec. (author)

  2. Low-temperature irradiation of niobium with 15-MeV neutrons

    International Nuclear Information System (INIS)

    Kerchner, H.R.; Coltman, R.R. Jr.; Klabunde, C.E.; Sekula, S.T.

    1978-01-01

    Niobium was irradiated at 4.2 K with high energy d-Be neutrons to a fluence of 3.7x10 15 n/cm 2 . The neutrons were generated at the Oak Ridge Isochronous Cyclotron by the breakup reaction of 40-MeV deuterons in a thick Be target. The resulting neutron energy spectrum was broadly peaked near 15 MeV. The 0.012-cm-diameter wire sample (RRR=200) was situated in a uniform transverse magnetic field. The critical current, flux flow resistance, and normal state resistance were measured by using a standard four-terminal technique. The critical current density and the flux flow resistivity were observed to increase with irradiation and to decrease toward the preirradiation values with subsequent isochronal annealing between 4.2 K and 360 K. Using recent theories of flux line lattice deformation, the elementary pinning force is deduced and the result is compared to theoretical calculations. (Auth.)

  3. Accelerator based synthesis of hydroxyapatite by MeV ion implantation

    International Nuclear Information System (INIS)

    Rautray, Tapash R.; Narayanan, R.; Kwon, Tae-Yub; Kim, Kyo-Han

    2010-01-01

    Accelerator based MeV ion implantation of Ca 2+ and P 2+ into the titanium substrate to form hydroxyapatite (HA) has been carried out. Calcium hydroxide was formed after heating the calcium implanted titanium in air at 80 o C for 3 h. Upon subsequent annealing for 5 min at 600 o C HA was formed on the surface. Penetration depth of the HA layer in this method is much higher as compared to keV ion implantation. By elemental analysis, Ca/P ratio of the HA was found to be 1.76 which is higher than the ideal 1.67. This higher Ca/P ratio is attributed to the higher penetration depth of the MeV technique used.

  4. Tooth enamel dosimetric response to 2.8 MeV neutrons

    Science.gov (United States)

    Fattibene, P.; Angelone, M.; Pillon, M.; De Coste, V.

    2003-03-01

    Tooth enamel dosimetry, based on electron paramagnetic resonance (EPR) spectroscopy, is recognized as a powerful method for individual retrospective dose assessment. The method is mainly used for individual dose reconstruction in the epidemiological studies aimed at the radiation risk analysis. The study of the sensitivity of tooth enamel as a function of radiation quality is one of the main goals of the research in this field. In the present work, tooth enamel dose response in a monoenergetic neutron flux of 2.8 MeV, generated by the D-D reaction, was studied for in air and in phantom irradiations of enamel samples and of whole teeth. EPR measurements were complemented by Monte Carlo calculation and by gamma dose discrimination obtained with thermoluminescent and Geiger-Muller tube measurements. The 2.8 MeV neutrons to 60Co relative sensitivity was 0.33±0.08.

  5. Tooth enamel dosimetric response to 2.8 MeV neutrons

    International Nuclear Information System (INIS)

    Fattibene, P.; Angelone, M.; Pillon, M.; De Coste, V.

    2003-01-01

    Tooth enamel dosimetry, based on electron paramagnetic resonance (EPR) spectroscopy, is recognized as a powerful method for individual retrospective dose assessment. The method is mainly used for individual dose reconstruction in the epidemiological studies aimed at the radiation risk analysis. The study of the sensitivity of tooth enamel as a function of radiation quality is one of the main goals of the research in this field. In the present work, tooth enamel dose response in a monoenergetic neutron flux of 2.8 MeV, generated by the D-D reaction, was studied for in air and in phantom irradiations of enamel samples and of whole teeth. EPR measurements were complemented by Monte Carlo calculation and by gamma dose discrimination obtained with thermoluminescent and Geiger-Muller tube measurements. The 2.8 MeV neutrons to 60 Co relative sensitivity was 0.33±0.08

  6. Optimum design for 12 MeV linear induction accelerator diode

    International Nuclear Information System (INIS)

    Yu Haijun; Shi Jinshui; Li Qin; He Guorong; Ma Bing; Wang Jingsheng; Wang Liping

    2001-01-01

    A series of optimization designs of electron diode in 12 Mev linear induction accelerator are studied by using numerical simulation code MAGIC and experiment method in order to improve the electron beam quality. MAGIC code solves the Maxwell equations in the presence of charged particle, electron field distribution on cathode surface which influences electron emission is given, the optimum diode is obtained by comparing the results of experiment in 12 MeV linear induction accelerator. The author also gives SEM analysis and experiment comparison of velvet emission. Finally, emitted current I e = 8.52 kA, beam current I 8 ≥ 3.0 kA, targeted current I 0 ≥ 2.30 kA with optimum diode are obtained

  7. The response of CR-39 nuclear track detector to 1-9 MeV protons

    International Nuclear Information System (INIS)

    Sinenian, N.; Rosenberg, M. J.; Manuel, M.; McDuffee, S. C.; Casey, D. T.; Zylstra, A. B.; Rinderknecht, H. G.; Gatu Johnson, M.; Seguin, F. H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D.

    2011-01-01

    The response of CR-39 nuclear track detector (TasTrak) to protons in the energy range of 0.92-9.28 MeV has been studied. Previous studies of the CR-39 response to protons have been extended by examining the piece-to-piece variability in addition to the effects of etch time and etchant temperature; it is shown that the shape of the CR-39 response curve to protons can vary from piece-to-piece. Effects due to the age of CR-39 have also been studied using 5.5 MeV alpha particles over a 5-year period. Track diameters were found to degrade with the age of the CR-39 itself rather than the age of the tracks, consistent with previous studies utilizing different CR-39 over shorter time periods.

  8. Neutron scattering from 12C between 15.6 and 17.3 MeV

    International Nuclear Information System (INIS)

    Chen, Z.M.; Baird, K.; Howell, C.R.; Roberts, M.L.; Tornow, W.; Walter, R.L.

    1993-01-01

    The differential cross section σ(θ) for neutron elastic scattering from 12 C and for inelastic scattering from the 4.44 MeV state was measured at 15.57, 16.75 and 17.29 MeV. The σ(θ) data, together with published analysing power A y (θ) data, were analysed in the framework of the spherical optical model and in the coupled-channels formalism. It was concluded that the present 12 C(n,n) 12 C data and published data at higher energies appear to be well suited for determining properties of valence single-particle excitations in 11 C via an iterative-moment approach or a dispersive optical-model analysis. (author)

  9. Neutron scattering from [sup 12]C between 15. 6 and 17. 3 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Z.M.; Baird, K.; Howell, C.R.; Roberts, M.L.; Tornow, W.; Walter, R.L. (Duke Univ., Durham, NC (United States). Dept. of Physics Triangle Universities Nuclear Lab., Durham, NC (United States))

    1993-06-01

    The differential cross section [sigma]([theta]) for neutron elastic scattering from [sup 12]C and for inelastic scattering from the 4.44 MeV state was measured at 15.57, 16.75 and 17.29 MeV. The [sigma]([theta]) data, together with published analysing power A[sub y]([theta]) data, were analysed in the framework of the spherical optical model and in the coupled-channels formalism. It was concluded that the present [sup 12]C(n,n)[sup 12]C data and published data at higher energies appear to be well suited for determining properties of valence single-particle excitations in [sup 11]C via an iterative-moment approach or a dispersive optical-model analysis. (author).

  10. Patterned microstructures formed with MeV Au implantation in Si(1 0 0)

    International Nuclear Information System (INIS)

    Rout, Bibhudutta; Greco, Richard R.; Zachry, Daniel P.; Dymnikov, Alexander D.; Glass, Gary A.

    2006-01-01

    Energetic (MeV) Au implantation in Si(1 0 0) (n-type) through masked micropatterns has been used to create layers resistant to KOH wet etching. Microscale patterns were produced in PMMA and SU(8) resist coatings on the silicon substrates using P-beam writing and developed. The silicon substrates were subsequently exposed using 1.5 MeV Au 3+ ions with fluences as high as 1 x 10 16 ions/cm 2 and additional patterns were exposed using copper scanning electron microscope calibration grids as masks on the silicon substrates. When wet etched with KOH microstructures were created in the silicon due to the resistance to KOH etching cause by the Au implantation. The process of combining the fabrication of masked patterns with P-beam writing with broad beam Au implantation through the masks can be a promising, cost-effective process for nanostructure engineering with Si

  11. Photonuclear and Radiation Effects Testing with a Refurbished 20 MeV Medical Electron Linac

    CERN Document Server

    Webb, Timothy; Beezhold, Wendland; De Veaux, Linda C; Harmon, Frank; Petrisko, Jill E; Spaulding, Randy

    2005-01-01

    An S-band 20 MeV electron linear accelerator formerly used for medical applications has been recommissioned to provide a wide range of photonuclear activation studies as well as various radiation effects on biological and microelectronic systems. Four radiation effect applications involving the electron/photon beams are described. Photonuclear activation of a stable isotope of oxygen provides an active means of characterizing polymer degradation. Biological irradiations of microorganisms including bacteria were used to study total dose and dose rate effects on survivability and the adaptation of these organisms to repeated exposures. Microelectronic devices including bipolar junction transistors (BJTs) and diodes were irradiated to study photocurrent from these devices as a function of peak dose rate with comparisons to computer modeling results. In addition, the 20 MeV linac may easily be converted to a medium energy neutron source which has been used to study neutron damage effects on transistors.

  12. n + 2759Co(En≤20 MeV) nuclear data calculation and analysis

    International Nuclear Information System (INIS)

    Wang Shunuan

    2006-01-01

    Whole set of nuclear data calculation in ENDF/B-6 format for n + 27 59 Co (E n ≤20 MeV) has been finished by using spherical optical model, coupled channel optical model, pre-equilibrium exciton model and Hauser-Fashbach equilibrium statistical model. The calculated cross sections, angular distributions, spectrum and double differential cross sections by using codes of APOM, ECIS95 and UNF are compared with all existing experimental data for n + 27 59 Co(E n ≤20 MeV) takefrom EXFOR. The calculated results are analyzed from point of view of theoretical model and model parameters used. The work is for CENDL-3. (authors)

  13. MeV ion beam interaction with polymer films containing cross-linking agents

    International Nuclear Information System (INIS)

    Evelyn, A. L.

    1999-01-01

    Polymer films containing cross linking enhancers were irradiated with MeV alpha particles to determine the effects of MeV ion beam interaction on these materials. The contributed effects from the electronic and nuclear stopping powers were separated by irradiating stacked thin films of polyvinyl chloride (PVC), polystyrene (PS) and polyethersulfone (PES). This layered system allowed most of the effects of the electronic energy deposited to be experienced by the first layers and the last layers to receive most of the effects of the nuclear stopping power. RGA, Raman microprobe analysis, RBS and FTIR measured changes in the chemical structures of the irradiated films. The characterization resolved the effects of the stopping powers on the PVC, PS and PES and the results were compared with those from previously studied polymers that did not contain any cross linking agents

  14. New newtron time-of-flight (NTOF) facilities at the Brookhaven 200-MeV Linac

    International Nuclear Information System (INIS)

    Ward, T.E.; Alessi, J.; Brennan, J.; Grand, P.; Lankshear, R.; Snead, C.L.; Tsoupas, N.; Zucker, M.

    1988-01-01

    The installation of a new beam chopper and radio-frequency quadrupole (RFQ) preinjector (750 keV) at the Brookhaven National Laboratory (BNL) 200-MeV Linac will enable single micropulse selection (pulse width 9 pμ pulse with dc-average beam currents of 50 nA-1 μA routinely available. The NTOF facilities consists of 30-100 meter flight paths at angles of 0, 12, 30, 45, 90, and 135/degree/. Lower energies of 93, 117, 139, 161, and 181 MeV are also available as well as polarized beams at much reduced intensities. The present paper describes the new facilities, and the capabilities of future improvements and upgrades, for use in the BNL intermediate energy (p,n) experimental program. 7 refs., 2 figs., 1 tab

  15. The analysis of air particulate deposits using 2 MeV protons

    International Nuclear Information System (INIS)

    Barfoot, K.M.; Mitchell, I.V.; Eschbach, H.L.; Mason, P.I.; Gilboy, W.B.

    1979-01-01

    Particle-induced X-ray emission (PIXE) analysis of the lighter elements in time-resolved air particulate deposits has been carried out. Minimum detection limits have been determined for 1.0, 2.0 and 3.5 MeV protons. Quantitative PIXE analysis results, obtained with 2 MeV protons, are given for temporal variations in the elemental concentrations of Na, Al, Si, S, Cl, K, Ca and Fe. Rutherford backscattering (RBS) spectra were taken simultaneously with the PIXE spectra to provide information on lead concentrations and deposit thicknesses. The experimental problems associated with the quantitative analysis of light elements on cellulose acetate filters are described. The relationship between these results and meteorological data is discussed. (author)

  16. Sputtering of vanadium and niobium under 14.1 MeV neutron impact

    International Nuclear Information System (INIS)

    Kaminsky, M.; Das, S.K.

    1976-01-01

    The recent studies of particle emission from cold-rolled and annealed niobium under 14.1-MeV neutron impact were extended to a heavily etched, polycrystalline niobium surface and to cold worked vanadium surfaces with different degrees of microstructure. The type and amount of material released and deposited on collector surfaces facing the irradiated targets were determined by three analytical techniques. Two types of deposits were found for certain types of surfaces--one in the form of chunks; the other as a fractional atom layer covering the surface. The chunks vary significantly in size. The small number of chunks observed suggests that the ejection of chunks is a relatively rare event in comparison to the total number of primary knock-on events produced by 14-MeV neutrons in near surface regions. Estimates of the total sputtering yield based on the chunk deposits and on the fractional atom layer deposit will be given

  17. Measurement of the 0.511 MeV #betta# ray line from the galactic center

    International Nuclear Information System (INIS)

    Jardim, J.O.D.; Benson, J.L.; Jardim, M.V.A.; Martin, I.M.

    1981-02-01

    The detection of the 0.511 MeV electron-positron annihilation line coming from the Galactic Center can provide the means to estimate the rate of positron production and to test some theoretical sources of positrons. The result of the measurements of the 0.511 MeV line flux made in a gamma-ray experiment on board a stratospheric balloon is presented. Thedetector field of view looked at the galactic longitude range-31 0 0 . The observed flux is (6.70 + - 0.85)x10 - 3 photons cm - 2 s - 1 , which is in good agreement with the expected flux when assuming that the Galactic Center is a line source emitting uniformly. (Author) [pt

  18. Amorphization and recrystallization in MeV ion implanted InP crystals

    International Nuclear Information System (INIS)

    Xiong, F.; Nieh, C.W.; Jamieson, D.N.; Vreeland, T. Jr.; Tombrello, T.A.

    1988-01-01

    A comprehensive study of MeV- 15 N-ion-implanted InP by a variety of analytical techniques has revealed the physical processes involved in MeV ion implantation into III-V compound semiconductors as well as the influence of post-implantation annealing. It provides a coherent picture of implant distribution, structural transition, crystalline damage, and lattice strain in InP crystals induced by ion implantation and thermal annealing. The experimental results from the different measurements are summarized in this report. Mechanisms of amorphization by implantation and recrystallization through annealing in MeV-ion-implanted InP are proposed and discussed in light of the results obtained

  19. Energy loss and straggling of MeV ions through biological samples

    International Nuclear Information System (INIS)

    Ma Lei; Wang Yugang; Xue Jianming; Chen Qizhong; Zhang Weiming; Zhang Yanwen

    2007-01-01

    Energy loss and energy straggling of energetic ions through natural dehydrated biological samples were investigated using transmission technique. Biological samples (onion membrane, egg coat, and tomato coat) with different mass thickness were studied, together with Mylar for comparison. The energy loss and energy straggling of MeV H and He ions after penetrating the biological and Mylar samples were measured. The experimental results show that the average energy losses of MeV ions through the biological samples are consistent with SRIM predictions; however, large deviation in energy straggling is observed between the measured results and the SRIM predictions. Taking into account inhomogeneity in mass density and structure of the biological sample, an energy straggling formula is suggested, and the experimental energy straggling values are well predicted by the proposed formula

  20. Cluster decay channel in 238U + 40Ar (243 MeV)

    International Nuclear Information System (INIS)

    Pyatkov, Yu.V.; Penionzhkevich, Yu.Eh.; Osetrov, O.I.

    1999-01-01

    The reaction 238 U + 40 Ar (E lab = 243 MeV) was studied. For the first time a pronounced fine structure (FS) in the form of distinct peaks has been observed in the mass yields of the fragments of the 278 110 nuclear system decay at the initial excitation of about 60 MeV. The FS peaks are located in the vicinity of the mass numbers A ∼ 70, 100, 130, which are specific for magic nuclei (clusters) of Ni, Ge, Zr, Sn, Sr. The FS peaks contain only low-energy events linked with the very elongated prescission configurations of the system. Some events are observed which can be treated as an indication of ternary fission via such configurations with the appearance of two equal clusters. Hence presumably the collinear cluster tripartition channel is realized observed earlier in the spontaneous fission of 248 Cm and 252 Cf nuclei

  1. Ion beam induced luminescence from diamond using an MeV ion microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, A A; Jamieson, D N; Prawer, S; Allen, M G [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1994-12-31

    Analysis of the luminescence induced by a MeV ion beam offers the potential to provide useful information about the chemical properties of atoms in crystals to complement the information provided by more traditional Ion Beam Analysis (IBA) such as Rutherford Backscattering Spectrometry (RBS), ion channeling and Particle Induced X-ray Emission (PIXE). Furthermore, the large penetration depth of the MeV ion beam offers several advantages over the relatively shallow penetration of keV electrons typically employed in cathodoluminescence. An Ion Beam Induced Luminescence (IBIL) detection system was developed for the Melbourne microprobe that allows the spatial mapping of the luminescence signal along with the signals from RBS and PIXE. Homoepitaxial diamond growth has been studied and remarkable shifts in the characteristic blue luminescence of diamond towards the green were observed in the overgrowth. This has been tentatively identified as being due to transition metal inclusions in the epitaxial layers. 8 refs., 2 refs.

  2. Production of iodine-123 radiobiological specimen on 25 MeV electron beam

    International Nuclear Information System (INIS)

    Oganesyan, Yu.Ts.; Starodub, G.Ya.; Buklanov, G.V.; Korotkin, Yu.S.; Belov, A.G.

    1988-01-01

    The technique is described and experimental results are presented for production of radioactive specimen-iodine-123 for medical biological investigations. It is shown that in ten hour irradiation of 124 Xe enriched target of 10 g weight by the 25 MeV electron beam at MT-25 microtron short lived 123 I with activity of about 200 mCl can be accumulated. The procedure was developed for extraction of radioactive atoms and preparing the solution that permits to obtain during 1-1.5 h after the end of irradiation the specimen which satisfies all pharmacopeia requirements. It follows from the results that using small-size electron accelerators with the beam energy up to 25 MeV permits to organize economical and large-scale production of high quality radioactive specimen of 123 I for servicing a large region of this country. 14 refs.; 4 figs.; 1 tab

  3. Effect of substrate temperature on the radiation damage from MeV Si implantation in Si

    International Nuclear Information System (INIS)

    Yu, X.K.; Shao Lin; Rusakova, Irene; Wang, X.M.; Ma, K.B.; Chen, H.; Liu, Jiarui; Chu, W.-K.

    2006-01-01

    We have investigated the radiation damage by MeV implantation of Si in Si and its evolution under thermal annealing. Si wafers were implanted with MeV Si at various substrate temperatures. Damages were characterized by Rutherford-backscattering (RBS) channeling and by transmission electron microscopy (TEM). Defect formation after post-implantation annealing is very sensitive to the substrate temperatures during implantation. When the substrate temperature was decreased to 200 K, TEM revealed two distinct bands of damage after annealing: one around the mean projected ion range and another at half the projected range. Our study indicates that the formation of defects at half range results from the solid phase epitaxy growth of initial buried amorphous layers

  4. Calibration Of A 14 MeV Neutron Generator With Reference To NBS-1

    International Nuclear Information System (INIS)

    Heimbach, Craig R.

    2011-01-01

    NBS-1 is the US national neutron reference source. It has a neutron emission rate (June 1961) of 1.257x10 6 n/s 1,2,3 with an uncertainty of 0.85%(k = 1). Neutron emission-rate calibrations performed at the National Institute of Standards and Technology (NIST) are made in comparison to this source, either directly or indirectly. To calibrate a commercial 14 MeV neutron generator, NIST performed a set of comparison measurements to evaluate the neutron output relative to NBS-1. The neutron output of the generator was determined with an uncertainty of about 7%(k = 1). The 15-hour half-life of one of the reactions used also makes possible off-site measurements. Consideration is given to similar calibrations for a 2.5 MeV neutron generator.

  5. SIMULATED 8 MeV NEUTRON RESPONSE FUNCTIONS OF A THIN SILICON NEUTRON SENSOR.

    Science.gov (United States)

    Takada, Masashi; Matsumoto, Tetsuro; Masuda, Akihiko; Nunomiya, Tomoya; Aoyama, Kei; Nakamura, Takashi

    2017-12-22

    Neutron response functions of a thin silicon neutron sensor are simulated using PHITS2 and MCNP6 codes for an 8 MeV neutron beam at angles of incidence of 0°, 30° and 60°. The contributions of alpha particles created from the 28Si(n,α)25Mg reaction and the silicon nuclei scattered elastically by neutrons in the silicon sensor have not been well reproduced using the MCNP6 code. The 8 MeV neutron response functions simulated using the PHITS2 code with an accurate event generator mode are in good agreement with experimental results and include the contributions of the alpha particles and silicon nuclei. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Physical design of 9 MeV travelling wave electron linac accelerating tube

    International Nuclear Information System (INIS)

    Chen Huaibi; Ding Xiaodong; Lin Yuzheng

    2000-01-01

    An accelerating tube is described. It is a part of an accelerator used for inspection of vehicle cargoes in rail cars, trucks, shipping containers, or airplanes in customs. A klystron with power of 4 MW and frequency of 2856 MHz will be applied to supply microwave power. The electrons can be accelerated by a travelling wave in the accelerating tube about 220 cm long, with a buncher whose capture efficiency is more than 80%. Energy of electrons after travelling through the tube can reach 9 MeV (pulse current intensity 170 mA) or 6 MeV (pulse current intensity 300 mA). Physical design of the accelerating tube, including the calculations of longitudinal particle dynamics, structure parameter and working character is carried out

  7. Plasma production for the 50 MeV plasma lens experiment at LBL

    International Nuclear Information System (INIS)

    Leemans, W.; van der Geer, B.; de Loos, M.; Conde, M.; Govil, R.; Chattopadhyay, S.

    1994-06-01

    The Center for Beam Physics at LBL has constructed a Beam Test Facility (BTF) housing a 50 MeV electron beam transport line, which uses the linac injector from the Advanced Light Source, and a terawatt Ti:Al 2 O 3 laser system. The linac operates at 50 MeV and generates 15 ps long electron bunches containing a charge of up to 2 nC. The measured unnormalized beam emittance is 0.33 mm-mrad. These parameters allow for a comprehensive study of focusing of relativistic electron beams with plasma columns, in both the overdense and underdense regime (adiabatic and tapered lenses). A study of adiabatic and/or tapered lenses requires careful control of plasma density and scale lengths of the plasma. We present experimental results on the production of plasmas through resonant two-photon ionization, with parameters relevant to an upcoming plasma lens experiment

  8. Cross sections from 800 MeV proton irradiation of terbium

    Energy Technology Data Exchange (ETDEWEB)

    Engle, J.W., E-mail: jwengle@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Mashnik, S.G.; Bach, H.; Couture, A.; Jackman, K.; Gritzo, R.; Ballard, B.D.; Fassbender, M.; Smith, D.M.; Bitteker, L.J.; Ullmann, J.L.; Gulley, M.S.; Pillai, C.; John, K.D.; Birnbaum, E.R. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Nortier, F.M., E-mail: meiring@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2012-11-02

    Terbium foils were irradiated with 800 MeV protons to ascertain the potential for production of lanthanide isotopes of interest in medical, astrophysical, and basic science research and to contribute to nuclear data repositories. Isotopes produced in the foil were quantified by gamma spectroscopy. Cross sections for 35 isotopes produced in the irradiation are reported and compared with predictions by the MCNP6 transport code using the CEM03.03, Bertini and INCL + ABLA event generators. Our results indicate the need to accurately consider fission and fragmentation of relatively light target nuclei like terbium in the modeling of nuclear reactions at 800 MeV. The predictive power of the code was found to be different for each event generator tested but was satisfactory for most of the product yields in the mass region where spallation reactions dominate. However, none of the event generators' results are in complete agreement with measured data.

  9. Ion beam induced luminescence from diamond using an MeV ion microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, A.A.; Jamieson, D. N.; Prawer, S.; Allen, M.G. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1993-12-31

    Analysis of the luminescence induced by a MeV ion beam offers the potential to provide useful information about the chemical properties of atoms in crystals to complement the information provided by more traditional Ion Beam Analysis (IBA) such as Rutherford Backscattering Spectrometry (RBS), ion channeling and Particle Induced X-ray Emission (PIXE). Furthermore, the large penetration depth of the MeV ion beam offers several advantages over the relatively shallow penetration of keV electrons typically employed in cathodoluminescence. An Ion Beam Induced Luminescence (IBIL) detection system was developed for the Melbourne microprobe that allows the spatial mapping of the luminescence signal along with the signals from RBS and PIXE. Homoepitaxial diamond growth has been studied and remarkable shifts in the characteristic blue luminescence of diamond towards the green were observed in the overgrowth. This has been tentatively identified as being due to transition metal inclusions in the epitaxial layers. 8 refs., 2 refs.

  10. Simulation code for the interaction of 14 MeV neutrons on cells

    Energy Technology Data Exchange (ETDEWEB)

    Nenot, M.L.; Alard, J.P.; Dionet, C.; Arnold, J.; Tchirkov, A.; Meunier, H.; Bodez, V.; Rapp, M.; Verrelle, P

    2002-07-01

    The structure of the survival curve of melanoma cells irradiated by 14 MeV neutrons displays unusual features at very low dose rate where a marked increase in cell killings at 0.05 Gy is followed by a plateau for survival from 0.1 to 0.32 Gy. In parallel a simulation code was constructed for the interaction of 14 MeV neutrons with cellular cultures. The code describes the interaction of the neutrons with the atomic nuclei of the cellular medium and of the external medium (flask culture and culture medium), and is used to compute the deposited energy into the cell volume. It was found that the large energy transfer events associated with heavy charged recoil can occur and that a large part of the energy deposition events are due to recoil protons emitted from the external medium. It is suggested that such events could partially explain the experimental results. (author)

  11. Finite-density transition line for QCD with 695 MeV dynamical fermions

    Science.gov (United States)

    Greensite, Jeff; Höllwieser, Roman

    2018-06-01

    We apply the relative weights method to SU(3) gauge theory with staggered fermions of mass 695 MeV at a set of temperatures in the range 151 ≤T ≤267 MeV , to obtain an effective Polyakov line action at each temperature. We then apply a mean field method to search for phase transitions in the effective theory at finite densities. The result is a transition line in the plane of temperature and chemical potential, with an end point at high temperature, as expected, but also a second end point at a lower temperature. We cannot rule out the possibilities that a transition line reappears at temperatures lower than the range investigated, or that the second end point is absent for light quarks.

  12. Transmission test of the polyethylene shield against 40 and 65 MeV quasi monochrome neutron

    International Nuclear Information System (INIS)

    Nakao, Makoto; Nakamura, Takashi; Sakuya, Yoshimasa; Nauchi, Yasushi; Nakao, Noriaki; Tanaka, Susumu; Sakamoto, Yukio; Nakajima, Hiroshi; Nakane, Yoshihiro.

    1996-01-01

    Using 40 and 65 MeV quasi monochrome neutron of the AVF cyclotron installed at Takasaki Laboratory, Japan Atomic Energy Research Institute, the neutron energy spectra were measured after transmitting the polyethylene shield. Results of the shielding experiments using concrete and iron recognized as main shielding material were proposed previously. As data obtained in the experiments were useful for a bench-mark experiment to investigate for shielding calculation and sectional data set, a shielding calculation simulated with new experiment to compare with and investigate for the previous experimental data. As a result, it was found that calculation result of neutron flux transmitting through the polyethylene shield showed difference with increase of the shield thickness. And, reducing distance of the peak neutron was also found to be over-estimated in its calculation value, such as three and five times on 43 MeV at 120 and 180 cm thick, respectively. (G.K.)

  13. A neutron survey meter with sensitivity extended up to 400 MeV

    International Nuclear Information System (INIS)

    Birattari, C.; Silari, M.

    1992-01-01

    The well-known Andersson-Braun rem counter is widely employed for radiation protection purposes, but its efficiency shows a marked decrease for neutron energies above about 10 MeV. Since the availability of a survey meter with a good sensitivity to higher energies can be very useful, for instance, at many particle accelerator facilities, a neutron monitor with a response function extended up to 400 MeV has been achieved by modifying the structure of the moderator-attenuator of a commercial instrument. The first experimental tests carried out to verify the response of the new monitor both to low and high energy neutrons are reported. A comparison with the response function of three conventional commercial rem counters is presented. (author)

  14. Measurements of 14 MeV neutron multiplication in spherical beryllium shells

    International Nuclear Information System (INIS)

    Moellendorff, U. von; Alevra, A.V.; Giese, H.; Kappler, F.; Klein, H.; Klein, H.; Tayama, R.

    1995-01-01

    New results of spherical-shell transmission measurements with 14MeV neutrons on pure beryllium shells up to 17cm thick are reported. The total leakage neutron multiplications were measured using a Bonner sphere system. Independently, the leakage neutron spectra were measured over the entire energy range, 15MeV to thermal energies, by proton-recoil and time-of-flight methods. The total leakage multiplications are in excellent agreement with three-dimensional Monte Carlo calculations using beryllium nuclear data based on the Young and Stewart evaluation. The leakage in the evaporation energy window confirms the Be(n,2n) cross-section of the Young and Stewart evaluation rather than that used in the ENDF/B-VI library. At energies below 1keV, a surplus of leakage neutrons over the calculation is found for smaller beryllium thicknesses. (orig.)

  15. Development of an MeV ion beam lithography system in Jyvaeskylae

    Energy Technology Data Exchange (ETDEWEB)

    Gorelick, Sergey [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FIN-40014 (Finland)]. E-mail: Sergey.Gorelick@phys.jyu.fi; Ylimaeki, Tommi [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FIN-40014 (Finland); Sajavaara, Timo [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FIN-40014 (Finland); Laitinen, Mikko [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FIN-40014 (Finland); Sagari, A.R.A. [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FIN-40014 (Finland); Whitlow, Harry J. [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FIN-40014 (Finland)

    2007-07-15

    A lithographic facility for writing patterns with ion beams from cyclotron beams is under development for the Jyvaeskylae cyclotron. Instead of focusing and deflecting the beam with electrostatic and magnetic fields a different approach is used. Here a small rectangular beam spot is defined by the shadow of a computer-controlled variable aperture in close proximity to the sample. This allows parallel exposure of rectangular pattern elements of 5-500 {mu}m side with protons up to 6 MeV and heavy ions ({sup 20}Ne, {sup 85}Kr) up to few 100 MeV. Here we present a short overview of the system under construction and development of the aperture design, which is a critical aspect for all ion beam lithography systems.

  16. Microscopic analysis of proton elastic scattering in the range 80-200 MeV

    International Nuclear Information System (INIS)

    Dietrich, F.S.; Petrovich, F.

    1983-01-01

    A systematic comparison is made of differential cross-section and analyzing-power data on 12 C, 28 Si, 40 Ca, 90 Zr, and 208 Pb at 80-200 MeV with calculations based on the single-step folding-model approach to the optical potential. In these calculations, proton densities have been inferred from electron scattering results, with neutron densities either the same as for protons ( 12 C, 28 Si, 40 Ca) or with a small neutron skin consistent with 800-MeV proton scattering results ( 80 Zr, 208 Pb). The effective two-body interactions that have been used are the Love-Franey t-matrix, a density-dependent interaction based on the Paris potential (calculated by von Geramb), and finally the Brieva-Rook density-dependent central interaction used with the spin-orbit part of the Love-Franey interaction

  17. The design of a proton recoil telescope for 14 MeV neutron spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hawkes, N.P.; Bond, D.S.; Croft, S.; Jarvis, O.N. E-mail: onj@jet.uk; Sherwood, A.C

    2002-01-01

    As part of the design effort for a 14 MeV neutron spectrometer for the Joint European Torus (JET), computer codes were developed to calculate the response of a proton recoil telescope comprising a proton radiator film mounted in front of a proton detector. The codes were used to optimise the geometrical configuration in terms of efficiency and resolution, bearing in mind the constraints imposed by the proposed application as a JET neutron diagnostic for the Deuterium-Tritium phase. A prototype instrument was built according to the optimised design, and tested with monoenergetic 14 MeV neutrons from the Harwell 500 keV Van de Graaff accelerator. The measured energy resolution and absolute efficiency were found to be in acceptable agreement with the calculations. Based on this work, a multi-radiator production version of the spectrometer has now been constructed and successfully deployed at JET.

  18. The design of a proton recoil telescope for 14 MeV neutron spectrometry

    International Nuclear Information System (INIS)

    Hawkes, N.P.; Bond, D.S.; Croft, S.; Jarvis, O.N.; Sherwood, A.C.

    2002-01-01

    As part of the design effort for a 14 MeV neutron spectrometer for the Joint European Torus (JET), computer codes were developed to calculate the response of a proton recoil telescope comprising a proton radiator film mounted in front of a proton detector. The codes were used to optimise the geometrical configuration in terms of efficiency and resolution, bearing in mind the constraints imposed by the proposed application as a JET neutron diagnostic for the Deuterium-Tritium phase. A prototype instrument was built according to the optimised design, and tested with monoenergetic 14 MeV neutrons from the Harwell 500 keV Van de Graaff accelerator. The measured energy resolution and absolute efficiency were found to be in acceptable agreement with the calculations. Based on this work, a multi-radiator production version of the spectrometer has now been constructed and successfully deployed at JET

  19. Neutron induced alpha production from carbon between 18 and 22 MeV

    International Nuclear Information System (INIS)

    Stevens, A.P.

    1976-10-01

    Cross sections for neutron induced alpha production in carbon were measured at seventeen energies between 18 and 22 MeV, using a deuterated anthracene crystal as both target and detector. Pulse shape discrimination was employed to separate the alphas and elastically scattered deuterons from the other reaction products. Published (n,d) elastic scattering data were used as a standard to obtain the alpha production cross sections. Comparison with available measurements shows good agreement

  20. Measurement of the analysing power of elastic proton-proton scattering at 582 MeV

    International Nuclear Information System (INIS)

    Berdoz, A.; Favier, B.; Foroughi, F.; Weddigen, C.

    1984-01-01

    The authors have measured the analysing power of elastic proton-proton scattering at 582 MeV for 14 angles from 20 to 80 0 CM. The angular range was limited to >20 0 by the energy loss of the recoil protons. The experiment was performed at the PM1 beam line at SIN. A beam intensity of about 10 8 particles s -1 was used. (Auth.)

  1. Elastic and inelastic scattering of 180 MeV π+- on 24Mg

    International Nuclear Information System (INIS)

    Gmitro, M.; Kvasil, J.; Mach, R.

    1982-01-01

    Equations of the coupled channel method written in the momentum space are solved for the scattering of 180 MeV pions on 24 Mg. The elastic and inelastic differential cross sections are calculated by using the nuclear ground-state- and transition-densities, which describe correctly the (e, e') data for the same nuclear states. The results agree well with the recent (π, π') data [ru

  2. Nuclear multifragmentation by 700–1500 MeV photons: New data of GRAAL experiment

    Energy Technology Data Exchange (ETDEWEB)

    Nedorezov, V. G., E-mail: vladimir@cpc.inr.ac.ru; Lapik, A. M. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation); Collaboration: GRAAL Collaboration

    2015-12-15

    The cross sections of carbon nucleus photodisintegration into protons and neutrons with high multiplicity for photon energies from 700 to 1500 MeV were measured. The experiment was performed at the tagged photon beam of the GRAAL setup using the wide-aperture detector LAGRANγE. It was shown that multifragmentation up to complete disintegration into separate nucleons is initiated by elementary reactions of meson photoproduction with a subsequent intranuclear cascade.

  3. Use of 13.5-MeV neutrons for protein determination in grain crops

    International Nuclear Information System (INIS)

    Barit, I.A.; Kuz'min, L.E.; Makarov, S.A.; Vozhzhov, V.F.; Pronman, I.M.

    1989-01-01

    One of the main objectives of the Food Supply Program, i.e., that of improving the quality of crop production, is bound up intimately with the intensification of work on the selection and genetics of high-protein grain and legume crops. High-protein stains cannot be isolated without the proper analytical service for mass testing of the nitrogen content in the grain, which is one of the main elements of protein. The neutron-activation method of nitrogen determination is based on the use of the 14 N(n, 2n) 13 N nuclear reaction (E th = 11.3 MeV) with an average neutron energy of ∼14.5 MeV. In this work the authors consider a new variant of the neutron-activation method of determining nitrogen in grain and legume crops. The method is based on the use of monoenergetic neutrons with an energy of ∼13.5 MeV, generated in relatively thin titanium-tritium targets by a mass-separated deuteron beam from neutron generators operating at 150-300 kV, in order to eliminate the interference of the reaction 39 K(n, 2n) 38 K (E thr = 13.4 MeV). The present method has been used to determine the protein content (mass %) in different grains and legumes at the All-Union Selection-Genetic Institute of the Lenin Academy of Agricultural Sciences. The correctness of the analysis was checked by comparison with the data of chemical analysis. The discrepancy between the results of the two methods does not exceed 3%, which is within the limits of the error of measurement of Δ and K s.r

  4. Survival of parenchymal hepatocytes exposed to 14.3-MeV neutrons

    International Nuclear Information System (INIS)

    Jirtle, R.L.; Gould, M.N.; DeLuca, P.M. Jr.; Pearson, D.W.

    1982-01-01

    This report presents the results of the measurement of a dose survival curve and RBE values for rat hepatic cells irradiated in vivo with 14.3 MeV neutrons. The purpose was to determine the RBE for neutrons as a function of dose, and whether hepatocytes exposed to neutrons are as efficient at repairing potentially lethal damage as they are after exposure to low LET radiation

  5. Evaluation of BPW-34 photodiode answer for 10 MeV electron dosimetry

    International Nuclear Information System (INIS)

    Khoury, H.J.; Melo, F.A.; Hazin, C.A.

    1992-01-01

    The viability of commercial photodiodes used for dosimetry of high energy electron beams was studied. The measures were made in a linear accelerators of 10 MeV, using the BPW-34 photodiode. The average energy of electrons on phantom surface and their average range were determined with the photodiode, and the results were compared with the obtained with a ionization chamber of parallel plate. (C.G.C.)

  6. Target asymmetry measurement of deuteron photodisintegration at a photon energy of 550 MeV

    International Nuclear Information System (INIS)

    Althoff, K.H.; Anton, G.; Bock, B.; Bour, D.; Erbs, P.; Ferber, W.; Gelhausen, H.; Haertel, U.; Havenith, W.; Jahnen, T.; Kaufmann, H.P.; Kaul, O.; Luecking, B.; Menze, D.; Meyer, W.; Miczaika, T.; Rennings, K.; Riechert, H.; Roderburg, E.; Ruhm, W.; Schenuit, E.; Schilling, E.; Schwille, W.; Sternal, G.; Sundermann, D.; Thiel, W.; Thiesmeyer, D.; Wagener, K.

    1984-01-01

    The target asymmetry of the deuteron photodisintegration was measured at a photon energy of 550+-50 MeV and at proton center-off-mass angles between 25 and 155 degrees. D-butanol and ND 3 were used as target material yielding a maximum deuteron polarization of 41%. Proton and neutron were detected in coincidence. The data show a structure which cannot be described by the existing analyses. (orig.)

  7. Design of the proposed 250 MeV superconducting cyclotron magnet for proton therapy

    International Nuclear Information System (INIS)

    Dey, M.K.; Ahmed, M.; Murali, S.; Duttagupta, A.; Chaudhuri, J.; Mallik, C.; Bhandari, R.K.

    2006-01-01

    Here we describe the design calculations for the superconducting magnet of a 250 MeV proton cyclotron to be used for therapeutic purpose. Hard-edge approximation method has been adopted for finding the poletip geometry to meet the basic focusing requirements of the beam. Then the uniform-magnetization method has been applied to calculate the 3D magnetic field distribution due to saturated iron poletips, to verify the beam dynamical issues. (author)

  8. Theoretical detection limit of PIXE analysis using 20 MeV proton beams

    Science.gov (United States)

    Ishii, Keizo; Hitomi, Keitaro

    2018-02-01

    Particle-induced X-ray emission (PIXE) analysis is usually performed using proton beams with energies in the range 2∼3 MeV because at these energies, the detection limit is low. The detection limit of PIXE analysis depends on the X-ray production cross-section, the continuous background of the PIXE spectrum and the experimental parameters such as the beam currents and the solid angle and detector efficiency of X-ray detector. Though the continuous background increases as the projectile energy increases, the cross-section of the X-ray increases as well. Therefore, the detection limit of high energy proton PIXE is not expected to increase significantly. We calculated the cross sections of continuous X-rays produced in several bremsstrahlung processes and estimated the detection limit of a 20 MeV proton PIXE analysis by modelling the Compton tail of the γ-rays produced in the nuclear reactions, and the escape effect on the secondary electron bremsstrahlung. We found that the Compton tail does not affect the detection limit when a thin X-ray detector is used, but the secondary electron bremsstrahlung escape effect does have an impact. We also confirmed that the detection limit of the PIXE analysis, when used with 4 μm polyethylene backing film and an integrated beam current of 1 μC, is 0.4∼2.0 ppm for proton energies in the range 10∼30 MeV and elements with Z = 16-90. This result demonstrates the usefulness of several 10 MeV cyclotrons for performing PIXE analysis. Cyclotrons with these properties are currently installed in positron emission tomography (PET) centers.

  9. ANL stochastic-cooling experiments using the FNAL 200-MeV cooling ring

    International Nuclear Information System (INIS)

    Hogrefe, R.L.; Kellogg, K.D.; Konecny, R.S.; Kramer, S.L.; Simpson, J.D.; Suddeth, D.E.; Hardek, T.W.

    1981-01-01

    Studies of stochastic momentum cooling are being conducted on the FNAL 200-MeV Storage Ring. The specific goal of the activity is to establish confidence in the theory and simulation methods used to describe the cooling process, and to develop techniques and devices suitable for use in the antiproton-accumulation scheme now planned for construction at FNAL. A summary of the activity, including hardware design, results of experiments, comparison with theory, and implications for the antiproton accumulator are presented

  10. 238U photonuclear studies with 5-10 MeV photons

    International Nuclear Information System (INIS)

    Hawkes, N.P.

    1986-02-01

    The 238 U photofission and photoneutron cross sections, and the mean number -ν of prompt neutrons per fission, have been measured between 5 and 10 MeV. The experiment was carried out using bremsstrahlung from the electron linear accelerator HELIOS at Harwell. Neutrons from (γ,f) and (γ,n) reactions on 238 U were detected, and neutron multiplicity distributions recorded. Photoneutron events were separated from photofission events by means of their different multiplicities. (author)

  11. The 665 KeV preinjector for the Nimrod 70 MeV injector

    International Nuclear Information System (INIS)

    Fowler, R.G.; Sidlow, R.; West, N.D.

    1976-09-01

    The preinjector for the new 70 MeV injector is described. A small duoplasmatron ion source supplies protons to the medium gradient accelerating column which is inside a glass fibre outer tube. The interspace between the column and outer tube contains sulphur hexafluoride gas as insulant. An HT platform, located close to the ion source end of the preinjector, contains the electronic power supplies necessary for the source. (author)

  12. Simultaneous determination of nitrogen and phosphorus in cereals using 14 MeV Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Bejarano, R.

    1992-01-01

    A method using 14 MeV neutron activation analysis was developed form non-destructive simultaneous determination of N and P in cereals. The samples were irradiated 5 min. after 0,5 min. decay time. The induced activities were measured using gamma spectrometry with Nal(Tl) well type detector. The accuracy, precision and detection limits obtained are discussed as well as the analytical results for different types of cereals. (Author) 10 refs., 8 tab., 1 fig

  13. Ring magnet power supply for a 500 MeV synchrotron

    International Nuclear Information System (INIS)

    Praeg, W.F.; McGhee, D.

    1978-01-01

    The ring magnets of a 500 MeV synchrotron at Argonne National Laboratory (ANL) are excited with a dc bias of 2300 A modulated by a 30 Hz sinewave current of 1300 A peak. To do this economically two commercial 500-kW 12-phase dc power supplies were modified to perform like a 1 MVA power amplifier with a frequency response from dc to approximately 60 Hz. This paper describes the design of the ring magnet power supply

  14. Calculated neutron spectrum from 800-MeV protons incident on a copper beam stop

    International Nuclear Information System (INIS)

    Perry, D.G.

    1975-10-01

    A Monte Carlo calculation was performed to obtain the neutron spectrum generated by 800-MeV protons incident on the LAMPF main copper beam stop. The total flux is calculated to be of the order of 10 13 n/cm 2 -sec-mA at full-beam intensity of 1 mA, with flux spectra calculated for angles of 20 0 , 30 0 , 60 0 , 90 0 , 120 0 , and 150 0 . (auth)

  15. THE ORIGIN OF THE COSMIC GAMMA-RAY BACKGROUND IN THE MeV RANGE

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Lapuente, Pilar [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, c/. Serrano 121, E-28006, Madrid (Spain); The, Lih-Sin; Hartmann, Dieter H.; Ajello, Marco [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634 (United States); Canal, Ramon [Institut de Ciències del Cosmos (UB-IEEC), c/. Martí i Franqués 1, E-08028, Barcelona (Spain); Röpke, Friedrich K.; Ohlmann, Sebastian T. [Institute of Theoretical Physics and Astrophysics, University of Würzburg, D-97074, Würzburg (Germany); Hillebrandt, Wolfgang [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching bei München (Germany)

    2016-04-01

    There has been much debate about the origin of the diffuse γ-ray background in the MeV range. At lower energies, AGNs and Seyfert galaxies can explain the background, but not above ≃0.3 MeV. Beyond ∼10 MeV blazars appear to account for the flux observed. That leaves an unexplained gap for which different candidates have been proposed, including annihilations of WIMPS. One candidate is Type Ia supernovae (SNe Ia). Early studies concluded that they were able to account for the γ-ray background in the gap, while later work attributed a significantly lower contribution to them. All those estimates were based on SN Ia explosion models that did not reflect the full 3D hydrodynamics of SN Ia explosions. In addition, new measurements obtained since 2010 have provided new, direct estimates of high-z SN Ia rates beyond z ∼ 2. We take into account these new advances to see the predicted contribution to the gamma-ray background. We use here a wide variety of explosion models and a plethora of new measurements of SN Ia rates. SNe Ia still fall short of the observed background. Only for a fit, which would imply ∼150% systematic error in detecting SN Ia events, do the theoretical predictions approach the observed fluxes. This fit is, however, at odds at the highest redshifts with recent SN Ia rate estimates. Other astrophysical sources such as flat-spectrum radio quasars do match the observed flux levels in the MeV regime, while SNe Ia make up to 30%–50% of the observed flux.

  16. Calculating Rayleigh scattering amplitudes from 100 eV to 10 MeV

    International Nuclear Information System (INIS)

    Parker, J.C.; Reynaud, G.W.; Botto, D.J.; Pratt, R.H.

    1979-01-01

    An attempt is made to explain how to calculate the contribution to elastic photon-atom scattering due to Rayleigh scattering (the scattering off bound electrons) in the photon energy range 100 eV less than or equal to W less than or equal to 10 MeV. All intermediate calculations are described, including the calculation of the potential, bound state wave functions, matrix elements, and final cross sections. 12 references

  17. THE ORIGIN OF THE COSMIC GAMMA-RAY BACKGROUND IN THE MeV RANGE

    International Nuclear Information System (INIS)

    Ruiz-Lapuente, Pilar; The, Lih-Sin; Hartmann, Dieter H.; Ajello, Marco; Canal, Ramon; Röpke, Friedrich K.; Ohlmann, Sebastian T.; Hillebrandt, Wolfgang

    2016-01-01

    There has been much debate about the origin of the diffuse γ-ray background in the MeV range. At lower energies, AGNs and Seyfert galaxies can explain the background, but not above ≃0.3 MeV. Beyond ∼10 MeV blazars appear to account for the flux observed. That leaves an unexplained gap for which different candidates have been proposed, including annihilations of WIMPS. One candidate is Type Ia supernovae (SNe Ia). Early studies concluded that they were able to account for the γ-ray background in the gap, while later work attributed a significantly lower contribution to them. All those estimates were based on SN Ia explosion models that did not reflect the full 3D hydrodynamics of SN Ia explosions. In addition, new measurements obtained since 2010 have provided new, direct estimates of high-z SN Ia rates beyond z ∼ 2. We take into account these new advances to see the predicted contribution to the gamma-ray background. We use here a wide variety of explosion models and a plethora of new measurements of SN Ia rates. SNe Ia still fall short of the observed background. Only for a fit, which would imply ∼150% systematic error in detecting SN Ia events, do the theoretical predictions approach the observed fluxes. This fit is, however, at odds at the highest redshifts with recent SN Ia rate estimates. Other astrophysical sources such as flat-spectrum radio quasars do match the observed flux levels in the MeV regime, while SNe Ia make up to 30%–50% of the observed flux

  18. Determination of phosphorus and potassium in sugar cane leaves by 14 MeV neutrons

    International Nuclear Information System (INIS)

    Diaz, R.A.; Nagy, A.Z.; Bakos, L.; Soria, J.C.

    1979-04-01

    The possibilities of N, P, K evaluation in samples of sugar cane leaves were discussed. A method for determining P and K content in this samples by 14 MeV neutron activation analysis is described. Corrections for K and Si were taken into account. The limit of detection for P was 0.1 mg and for K it was 4 mg. The precision for P and K was 10% in agreement with the values given by other authors. (author)

  19. The πNN coupling from high precision np charge exchange at 162 MeV

    International Nuclear Information System (INIS)

    Nilsson, J.; Blomgren, J.; Conde, H.; Elmgren, K.; Olsson, N.; Ericson, T.E.O.; Uppsala Univ.; Jonsson, O.; Nilsson, L.; Loiseau, B.; Ringbom, A.

    1995-02-01

    Differential cross sections for unpolarized neutrons of 162 MeV have been measured to high precision with particular attention to the absolute normalisation. These data can be extrapolated precisely and model-independently to the pion pole and give a πNN coupling constant g 2 =14.6±0.3 or f 2 =0.0808±0.0017. This is higher than recently suggested values. (author) 24 refs.; 3 figs.; 1 tab

  20. Fission cross section of 235U from 1 to 6 MeV

    International Nuclear Information System (INIS)

    Barton, D.M.; Diven, B.C.; Hansen, G.E.; Jarvis, G.A.; Koontz, P.G.; Smith, R.K.

    1976-01-01

    The ratio of the neutron-induced fission cross section of 235 U to the neutron-proton scattering cross section was measured in the neutron energy region from 1 to 6 MeV. The neutron source was the T(p,n) reaction produced by a pulsed Van de Graaff proton beam on a thin tritium gas target. The use of monoenergetic neutrons allowed time-of-flight methods to be used to study carefully backgrounds and source characteristics

  1. Fluorescence lifetime studies of MeV erbium implanted silica glass

    International Nuclear Information System (INIS)

    Lidgard, A.; Polman, A.; Jacobsen, D.C.; Blonder, G.E.; Kistler, R.; Poate, J.M.; Becker, P.C.

    1991-01-01

    MeV erbium ion implantation into various SiO 2 glasses has been studied with the aim of incorporating the rare-earth dopant as an optically active ion in the silica network. The lifetime of the excited state ranges from 1.6 to 12.8 ms, depending on base material and implantation fluence. These results have positive implications for silica-based integrated optical technology. (Author)

  2. Fluorescence lifetime studies of MeV erbium implanted silica glass

    Energy Technology Data Exchange (ETDEWEB)

    Lidgard, A.; Polman, A.; Jacobsen, D.C.; Blonder, G.E.; Kistler, R.; Poate, J.M.; Becker, P.C. (AT and T Bell Labs., Murray Hill, NJ (USA))

    1991-05-23

    MeV erbium ion implantation into various SiO{sub 2} glasses has been studied with the aim of incorporating the rare-earth dopant as an optically active ion in the silica network. The lifetime of the excited state ranges from 1.6 to 12.8 ms, depending on base material and implantation fluence. These results have positive implications for silica-based integrated optical technology. (Author).

  3. 12C(3He,3He n)11C cross section at 910 MeV

    International Nuclear Information System (INIS)

    Aslanides, E.; Fassnacht, P.; Dellacasa, G.; Gallio, M.; Tuyn, J.W.N.

    1981-01-01

    The 12 C( 3 He, 3 He n) 11 C cross section at 910 MeV was measured by using a Ge(Li) gamma spectrometer to determine the disintegration rate and measuring the incident flux by means of a scintillator telescope. Cross sections for the production of 7 Be in C and Al and for the production of 24 Na in Al are then determined using the measured cross section as a monitor

  4. Pion production in 3He-nucleus interactions at 910 MeV

    International Nuclear Information System (INIS)

    Aslanides, E.; Baumann, P.; Bergdolt, G.; Engelstein, P.; Fassnacht, P.; Hibou, F.; Bressani, T.; Puddu, G.A.

    1983-01-01

    The ( 3 He, πsup(+-)X) reaction has been studied at 910 MeV using the 3 He ++ beam of the CERN SC, Complete π - spectra on CH 2 , CD 2 , 9 Be, 12 C, 27 Al, Cd and Pb, and π + spectra on CH 2 , CD 2 and 12 C targets have been measured at 0 0 , up or close to the kinematic limit xsub(F)=1. The results are compared to various theoretical calculations. (orig.)

  5. Secondary electron emission from 0.5--2.5-MeV protons and deuterons

    International Nuclear Information System (INIS)

    Thornton, T.A.; Anno, J.N.

    1977-01-01

    Measurement of the secondary electron currents leaving Al, V, Fe, 316 stainless steel, Nb, and Mo foils undergoing 0.5--2.5-MeV proton and deuteron bombardment were made to determine the secondary electron emission ratios for these ions. The measured secondary electron yields were of the order of 1.0, with the deuterons producing generally higher yields than the protons

  6. Radiography studies with gamma rays produced by 14-MeV fusion neutrons

    International Nuclear Information System (INIS)

    Smith, D.L.; Ikeda, Yujiro; Uno, Yoshitomo

    1996-01-01

    Oxygen contained in pure water has been activated via the 16 O(n, p) 16 N reaction using 14-MeV neutrons produced at a neutron generator with the 3 H(d,n) 4 He source. Photons of 6.129 and 7.115 MeV, generated by the decay of 7.13-second 16 N, were then used to demonstrate the feasibility of employing highly penetrating, nearly monoenergetic gamma rays for radiography studies of thick, dense objects composed of elements with medium to relatively high atomic numbers. A simple radiography apparatus was constructed by circulating water continuously between a position near the target of the neutron generator and a remote location where photon transmission measurements were conducted. A sodium iodide scintillator was employed to detect the photons. Pulses equivalent to photon energies smaller than 2.506 MeV (corresponding to the cascade sum of 1.333- and 1.173-MeV gamma rays from the decay of 5.271-year 60 Co) were rejected by the electronics settings in order to reduce background and improve the signal-to-noise (S/N) ratio. Respectable S/N ratios on the order of 20-to-1 were achieved with this setup. Most of the background (N) could be attributed to ambient environmental radiation and cosmic-ray interactions with the lead shielding and detector. Four representative objects were examined by photon radiography in this study. This demonstrated how such - interesting features as hidden holes and discontinuities in atomic number could be easily identified from observed variations in the intensity of transmitted photons. Some advantages of this technique are described, and potential applications are suggested for a future scenario where fusion reactors are used to generate electric power and very intense sources of high-energy photons from 16 N decay are continuously available as a byproduct of the reactor cooling process

  7. Interactions of 29 MeV. He3 particles with light nuclei

    International Nuclear Information System (INIS)

    de la Rubia Pacheco, J.

    1964-01-01

    The interactions of 29 MeV He 3 particles with 32 S , 19 F and 12 C , irradiated in the Nuffield cyclotron (Birmingham University) have been studied using the nuclear emulsion technique. The first excitation levels of 12 C and 32 S have been obtained and the pick-up reaction 12 C (3 H e, 4 H e) 11 C has been studied and used to calculate its Q-values and the first levels of 1 C . (Author) 24 refs

  8. Determination of oxygen content in steel using activation analysis with 14 MeV neutron

    International Nuclear Information System (INIS)

    Calado, C.E.

    1978-01-01

    In the quantitative analysis of oxygen in steel by fast neutron activation analysis the oxygen content is evaluated from the measured activity of 16 N produced. Steel s mples are irradiated in 14 MeV neutron flux. After irradiation the samples are pneumatically transfered to the counting terminal where activity is measured. Oxygen concentrations, are obtained by comparison with standards of specified oxygen content [pt

  9. Operational characteristics of a 100-mA, 2-MeV radio-frequency quadrupole

    International Nuclear Information System (INIS)

    Johnson, K.F.; Cottingame, W.B.; Bolme, G.O.; Fortgang, C.M.; Ingalls, W.B.; Marquardt, J.; Rusthoi, D.P.; Sander, O.R.; Smith, M.; Worth, G.T.

    1993-01-01

    A 100-mA, 2.07-MeV Radio-Frequency Quadrupole (RFQ III) has been commissioned and operated routinely on the Accelerator Test Stand (ATS) [1] at Los Alamos National Laboratory. To characterize the RFQ output beam dynamics, measurements were made of the beam transmission and of the transverse and longitudinal phase-space distributions. Data were taken for different RFQ III operating conditions and compared to simulations

  10. Transmission property and its applications of MeV ion beams with various capillaries

    International Nuclear Information System (INIS)

    Fujita, N; Ishii, K; Ogawa, H

    2012-01-01

    In order to clarify transmission properties of an ion beam extracted with various capillaries into the air, we have measured intensity distributions for the core and the halo components of MeV ion beams using various capillaries. In addition, we have performed in-air-RBS and in-air-PIXE from the point of the application. At the conference, progress report of transmission properties of ion beams with various capillaries and its applications will be presented.

  11. Photoreactivity in Saccharomyces cerevisiae cells after irradiation with 25 MeV electrons

    International Nuclear Information System (INIS)

    Tsyb, T.S.; Seleva, N.G.; Myasnik, M.N.; Kabakova, N.M.

    1986-01-01

    Significant photoreactivation was noted in radio- and UV-sensitive rad-mutants of Saccharomyces cerevisiae cells exposed to 25 MeV electrons. In order to make the photoreactivable damage be manifest anoxic conditions of irradiation should be chosen as optimal ones. It was shown that the low oxygen effect was partially associated with the photoreactivable damage involved in the lethal effect of ionizing radiation

  12. Accelerating structure of the CERN new 50 MeV linac

    International Nuclear Information System (INIS)

    Warner, D.J.

    1976-01-01

    The design of the post-coupled Alvarez structure is presented with emphasis on features which are novel and critical especially as regards acceleration of high currents (150 mA) to 50 MeV. Among topics treated are the sequence of computational techniques leading from unit cell (e.m. field) calculations to dynamics of the complete linac, and model measurements which justify the drift-tube girder support approach and our particular post-coupler arrangement. (author)

  13. The tagged photon beam facility at the Bonn 500 MeV synchrotron

    International Nuclear Information System (INIS)

    Arends, J.; Eyink, J.; Hartmann, H.; Hegerath, A.; Mecking, B.; Ros, H.

    1982-01-01

    A facility for the investigation of medium energy photonuclear reactions is described. A bremsstrahlung tagging system produces a precisely known flux of monochromatic photons in the energy range between 100 and 450 MeV. Resolution and intensity of the system are given. Photoemitted particles can be detected in various large solid angle detectors. The performance of the facility and future developments are discussed. (orig.)

  14. Electroexcitation of 15N levels from 9.7 to 14.7 MeV

    International Nuclear Information System (INIS)

    Ansaldo, E.J.; Bergstrom, J.C.; Caplan, H.S.; Yen, R.

    1977-01-01

    The electromagnetic form factors of five transitions in 15 N have been measured for momentum transfers between 0.48 and 1.27 fm -1 . The transitions observed were identified with levels at 9.76, 10.80, 11.88, 12.50, and 14.7 MeV excitation energy. Ground state radiative widths have been extracted by a Helm model analysis. (author)

  15. Subnanosecond pulsing of an 1 MeV ELIT electron accelerator by beam deflection

    International Nuclear Information System (INIS)

    Vasserman, S.B.; Kuzenko, V.; Mehnert, R.; Hermann, R.

    1984-01-01

    Operation principle and performance of a beam deflection system developed for subnanosecond pulsing of an 1 MeV ELIT resonance transformer accelerator are described. Using this system a minimum pulse duration of 0.5 ns (FWHM) and a dose per pulse of about 20 Gy were obtained. As an example the fluorescence of cyclohexane excited by the subnanosecond electron pulse was measured. (author)

  16. Characterization of 10 MeV electron linac for radiation processing

    International Nuclear Information System (INIS)

    Petwal, V.C.; Rao, J.N.; Kaul, A.; Bapna, S.C.; Mulchandani, J.K.; Wanmode, Y.; Pandiyar, M.; Srivastava, P.; Jain, Akhilesh; Hanurkar, P.R.

    2006-01-01

    A radiation processing facility based on a 10 MeV LINAC is being set-up at RRCAT. In the course of commissioning various experiments have been carried-out to characterize the radiation field generated by the accelerator and subsequently to derive the operating parameters of the facility for radiation processing of various items. Results of the experiments are presented in the paper. (author)

  17. Measurement of neutron captured cross-sections in 1-2 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gi Dong; Kim, Young Sek; Kim, Jun Kon; Yang, Tae Keun [Korea Institutes of Geoscience and Mineral Resources, Taejeon (Korea)

    2001-04-01

    The measurement of neutron captured reaction cross sections was performed to build the infra system for the production of nuclear data. MeV neutrons were produced with TiT target and {sup 3}T(p,n){sup 3}He reaction. The characteristics of TiT thin film was analyzed with ERD-TOF and RBS. The results was published at Journal of the Korea Physical Society (SCI registration). The energy, the energy spread and the flux of the produced neutron were measured. The neutron excitation functions of {sup 12}C and {sup 16}O were obtained to confirm the neutron energy and neutron energy spread. The neutron energy spread found to be 1.3 % at the neutron energy of 2.077 MeV. The {sup 197}Au(n,{gamma}) reaction was performed to obtain the nerutron flux. The maximum neutron flux found to be 1 x 10{sup 8} neutrons/sec at the neutron energy of 2 MeV. The absolute efficiency of liquid scintillation detector was obtained in the neutron energy of 1 - 2 MeV. The fast neutron total reaction cross sections of Cu, Fe, and Au were measured with sample in-out method. Also the neutron captured reaction cross sections of {sup 63}Cu were measured with fast neutron activation method. The measurement of neutron total reaction cross sections and the neutron captured reaction cross sections with fast neutrons were first tried in Korea. The beam pulsing system was investigated and the code of calculating the deposition spectrums for primary gamma rays was made to have little errors at nuclear data. 25 refs., 28 figs., 14 tabs. (Author)

  18. Biomedical user facility at the 400-MeV Linac at Fermilab

    International Nuclear Information System (INIS)

    Chu, W.T.

    1993-12-01

    In this paper, general requirements are discussed on a biomedical user facility at the Fermilab's 400-MeV Linac, which meets the needs of biology and biophysics experiments, and a conceptual design and typical operations requirements of the facility is presented. It is assumed that no human patient treatment will take place in this facility. If human patients were treated, much greater attention would have to be paid to safeguarding the patients

  19. The 208Pb(7Li,6He)209Bi reaction at 52 MeV

    International Nuclear Information System (INIS)

    Zeller, A.F.; Weisser, D.C.; Ophel, T.R.; Hebbard, D.F.

    1979-11-01

    Single proton transfers to low lying levels in 209 Bi from the 208 Pb(7Li, 6 He) reaction at 52 MeV have been measured and spectroscopic factors derived from an EFR-DWBA analysis. Relative spectroscopic factors are in good agreement with light ion results and previous heavy ion work. Absolute spectroscopic factors were generally too large and the peaks of the angular distributions were out of phase with the DWBA calculations by 1 0 - 4 0

  20. (p,3He) reactions on 1p shell nuclei at 41 and 45 MeV

    International Nuclear Information System (INIS)

    Rapp, V.

    1982-01-01

    In the present thesis the (p, 3 He) reactions on target nuclei of the 1p shell were studied. The measurements were performed at the isochronous cyclotron of the KFA Juelich. Angular distribution at 41 and 45 MeV to residual nuclear states in 7 Li, 8 Be, 9 Be, 10 B, 11 B, 12 C, 13 C, and 14 N. were evaluated. (orig.) [de

  1. Stripping Foil Issues for H- Injection into the CERN PSB at 160 MeV

    CERN Document Server

    Goddard, B; Bracco, C; Carli, C; Meddahi, M; Weterings, W J M

    2010-01-01

    Beam physics considerations for the stripping foil of the 160 MeV PSB H- injection systems are described, including the arguments for the foil type, thickness, geometry and positioning. The foil performance considerations are described, including expected stripping efficiency, emittance growth, energy straggling, temperature and lifetime. The different beam loss mechanisms are quantified in the context of the aperture limits, operational considerations and collimation requirements.

  2. Transport calculations for a 14.8 MeV neutron beam in a water phantom

    International Nuclear Information System (INIS)

    Goetsch, S.J.

    1981-01-01

    A coupled neutron/photon Monte Carlo radiation transport code (MORSE-CG) has been used to calculate neutron and photon doses in a water phantom irradiated by 14.8 MeV neutrons from the Gas Target Neutron Source. The source-collimator-phantom geometry was carefully simulated. Results of calculations utilizing two different statistical estimators (next-collision and track-length) are presented

  3. Interaction of 80 MeV PI+ with different targets: Track detector studies

    Energy Technology Data Exchange (ETDEWEB)

    Tabassum, L; Chohan, A S [Government Coll., Lahore. (Pakistan) Deptt. of Physics Khan, H.A. (Pakistan Inst. of Nuclear Science and Technology, Islamabad (Pakistan). Nuclear Engineering Div.)

    1990-04-01

    CR-39 and mica track detectors have been used in the study of the interactions of 80 MeV PI+ with thin targets of Bi, Pb, Ho, Sb. The binary fission cross sections, the length and angular distributions of etched tracks have been obtained. The cross-section values obtained by using CR-39 are higher as compared to those obtained with mica. (author).

  4. Interaction of 80 MeV PI+ with different targets: Track detector studies

    International Nuclear Information System (INIS)

    Tabassum, L.; Chohan, A.S.

    1990-01-01

    CR-39 and mica track detectors have been used in the study of the interactions of 80 MeV PI+ with thin targets of Bi, Pb, Ho, Sb. The binary fission cross sections, the length and angular distributions of etched tracks have been obtained. The cross-section values obtained by using CR-39 are higher as compared to those obtained with mica. (author)

  5. Reaction mechanisms in 12C(γ,pp) near 200 MeV

    Science.gov (United States)

    Hackett, E. D.; McDonald, W. J.; Opper, A. K.; Quraan, M. A.; Rodning, N. L.; Rozon, F. M.; Feldman, G.; Kolb, N. R.; Pywell, R. E.; Skopik, D. M.; Tiller, D. E.; Vogt, J. M.; Korkmaz, E.; O'rielly, G. V.

    1996-03-01

    Inclusive 12C(γ,pp) cross sections have been measured with tagged photons in the range Eγ=187-227 MeV using the Saskatchewan-Alberta Large Acceptance Detector (SALAD). The large angular acceptance allowed the measurement of noncoplanar pp emission. The cross sections were compared to a Monte Carlo intranuclear cascade calculation. Agreement was reasonable for the shapes of the cross sections but the calculated total cross section was 3.9 times larger than the data.

  6. Instrumentation and control system for PLS-IM-T 60 MeV LINAC

    International Nuclear Information System (INIS)

    Liu, D.K.; Yei, K.R.; Cheng, H.J.

    1992-01-01

    The PLSIMT is a 60 MeV LINAC as a preinjector for 2 GeV LINAC of PLS project. The instrumentation and control system have been designed under the institutional collaboration between the IHEP (Beijing, China) and POSTECH (Pohang, Korea). So far, the I and C system are being set up nowadays at the POSTECH of Pohang. This paper describes its major characteristics and present status. (author)

  7. Systematics in total (n,2n) cross sections at 14 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Garg, K C; Khurana, C S [Punjabi Univ., Patiala (India). Nuclear Science Labs.

    1976-11-20

    The 14-15 MeV (n,2n) cross sections are found to depend mainly on the asymmetry parameter and the Q-value. No shell effects are found to exist in these cross sections. The total (n,2n) cross sections are found to be well predicted by an empirical relation which takes into account the Q-value and the asymmetry parameter in addition to the geometrical cross section.

  8. Use of the SPIRAL 2 facility for material irradiations with 14 MeV energy neutrons

    International Nuclear Information System (INIS)

    Mosnier, A.; Ridikas, D.; Ledoux, X.; Pellemoine, F.; Anne, R.; Huguet, Y.; Lipa, M.; Magaud, P.; Marbach, G.; Saint-Laurent, M.G.; Villari, A.C.C.

    2005-01-01

    The primary goal of an irradiation facility for fusion applications will be to generate a material irradiation database for the design, construction, licensing and safe operation of a fusion demonstration power station (e.g., DEMO). This will be achieved through testing and qualifying material performance under neutron irradiation that simulates service up to the full lifetime anticipated in the power plant. Preliminary investigations of 14 MeV neutron effects on different kinds of fusion material could be assessed by the SPIRAL 2 Project at GANIL (Caen, France), aiming at rare isotope beams production for nuclear physics research with first beams expected by 2009. In SPIRAL 2, a deuteron beam of 5 mA and 40 MeV interacts with a rotating carbon disk producing high-energy neutrons (in the range between 1 and 40 MeV) via C (d, xn) reactions. Then, the facility could be used for 3-4 months y -1 for material irradiation purposes. This would correspond to damage rates in the order of 1-2 dpa y -1 (in Fe) in a volume of ∼10 cm 3 . Therefore, the use of miniaturized specimens will be essential in order to effectively utilize the available irradiation volume in SPIRAL 2. Sample package irradiation temperature would be in the range of 250-1000 deg. C. The irradiation level of 1-2 dpa y -1 with 14 MeV neutrons (average energy) may be interesting for micro-structural and metallurgical investigations (e.g., mini-traction, small punch tests, etc.) and possibly for the understanding of specimen size/geometric effects of critical material properties. Due to the small test cell volume, sample in situ experiments are not foreseen. However, sample packages would be, if required, available each month after transfer in a special hot cell on-site

  9. Activation analysis course experiments with a 14-MeV neutron generator

    International Nuclear Information System (INIS)

    Miller, D.A.; Miller, G.E.

    1976-01-01

    The use of a 14 MeV neutron generator system in the radiochemistry teaching program of the Chemistry Department of the University of California at Irvine is described. Several different types of experiment are outlined to indicate the broad applicability of such a system to an instructional program in Chemistry. The program has encompassed instruction of undergraduates, graduate students and a Summer Institute Workshop for College Professors

  10. Polarization measurements in p-p elastic scattering between 398 and 572 MeV

    International Nuclear Information System (INIS)

    Aebischer, D.; Favier, B.; Greeniaus, L.G.; Hess, R.; Junod, A.; Lechanoine, C.; Nikles, J.C.; Rapin, D.; Werren, D.W.

    1977-01-01

    Measurements of the analyzing power for p-p elastic scattering at 398, 455, 497, 530, and 572 MeV are reported. A system of multiwire proportional chambers placed directly in a polarized beam was used to observe the angular region 1.5 0 0 . An increase in P(theta) is observed as a function of both scattering angle and incident kinetic energy. Electromagnetic-nuclear interference is used to obtain direct information in the nuclear interaction. (Auth.)

  11. Study of the reaction pp → π+d at 576 MeV

    International Nuclear Information System (INIS)

    Aebischer, D.; Favier, B.; Greeniaus, G.; Hess, R.; Junod, A.; Lechanoine, C.; Nikles, J.C.; Rapin, D.; Werren, D.W.

    1975-01-01

    A 576 MeV polarized proton beam has been used to study the pp → π + d reaction for small centre of mass π-production angles. The final state π and d were observed using a system of multiwire proportional chambers. The presence of a term in cos 4 thetasub(cm) for the differential cross-section has been tested. The left-right π production asymmetry for a transversely polarized beam has also been measured. (Auth.)

  12. Hot composite systems with a > 200 and T > 6 MeV

    International Nuclear Information System (INIS)

    Crema, E.; Bresson, S.; Doubre, H.; Galin, J.; Guerreau, D.; Morjean, M.; Piasecki, E.; Pouthas, J.; Saint-Laurent, F.; Sokolov, A.; Wang, X.M.; Gatty, B.; Jacquet, D.; Piasecki, E.; Crema, E.; Wang, X.M.

    1990-01-01

    Neutron multiplicities have been measured in coincidence with the light charged particles evaporated in the backward direction for the reaction 84 Kr+ 197 Au at 32 MeV/u. A method is presented which makes possible an evaluation of the recoil velocity, excitation energy and temperature of hot and thermalized heavy composite systems formed for different impact parameters. Temperatures larger than 6 MeV are found for the most dissipative collisions

  13. rvec p + 13 rvec C elastic scattering at 500 MeV

    International Nuclear Information System (INIS)

    Tanaka, N.

    1990-01-01

    For the first time, an elastic scattering experiment was performed at LAMPF using polarized protons and a polarized target nucleus (rvec p + 13 rvec C). The analyzing powers [A ooon (Θ)] and [A oonn (Θ)] were measured using an incident beam energy of 500 MeV over the laboratory angular range of 10 degree--30 degree. Motivation for the experiment and some preliminary results and conclusions are presented. 12 refs., 7 figs

  14. Identification of a pseudoscalar state at 1440 MeV in J/psi radiative decays

    International Nuclear Information System (INIS)

    Edwards, C.; Partridge, R.; Peck, C.; Porter, F.C.; Antreasyan, D.; Gu, Y.F.; Irion, J.; Kollmann, W.; Richardson, M.; Strauch, K.; Wacker, K.; Weinstein, A.; Aschman, D.; Burnett, T.; Cavalli-Sforza, M.; Coyne, D.; Newman, C.; Sadrozinski, H.F.W.; Gelphman, D.; Hofstadter, R.; Horisberger, R.; Kirkbride, I.; Kolanoski, H.; Koenigsmann, K.; Lee, R.; Liberman, A.; O'Reilly, J.; Osterheld, A.; Pollock, B.; Tompkins, J.; Bloom, E.D.; Bulos, F.; Chestnut, R.; Gaiser, J.; Godfrey, G.; Kiesling, C.; Lockman, W.; Oreglia, M.; Scharre, D.L.

    1982-01-01

    From a partial-wave analysis of the KK-barπ system in the decay J/psi→γK + K - π 0 , it is determined that the quantum numbers of the KK-barπ resonance at 1440 MeV, previously identified as the E(1420), are J/sup P/C = 0 -+ . This new particle has been named the iota

  15. Optical model studies of 6Li elastic scattering at 156 MeV

    International Nuclear Information System (INIS)

    Cook, J.; Gils, H.J.; Rebel, H.; Klewe-Nebenius, H.

    1981-11-01

    Differential cross sections for 6 Li elastic scattering at 156 MeV from 12 C, 40 Ca 90 Zr and 208 Pb are presented. The sensitivity to various potential forms is established by using Saxon Woods, Saxon-Woods-squred, density independent and density dependent folded potentials. The extent to which the experimental data determine the potentials and related quantities is discussed. (orig.) [de

  16. 238U and 237Np nuclear fission by 90-270 MeV electrons

    International Nuclear Information System (INIS)

    Kuznetsov, V.L.; Nedorezov, V.G.; Nikitina, N.V.; Noga, V.I.; Ranyuk, Yu.N.; Telegin, Yu.N.; Smirnov, A.N.; Ehjsmont, V.P.

    1981-01-01

    A technique for measuring cross sections of 238 U and 237 Np nuclei fission caused by 90-270 MeV electrons is described. Measurement results are given. The results obtained are discussed on the basis of the virtual photon method. It is shown that the difference in cross sections of 238 U and 237 Np electrofission is due to the different contribution of the giant resonance [ru

  17. Detection of electrons in the 10 MeV range by plastic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Beaudoin, G; Champagne, A; Jeremie, H; Lessard, L

    1986-09-10

    Response functions for electrons from 1 to 12 MeV have been measured with a plastic scintillator telescope. A parametrization model for these response functions has been found to give good results at all energies. Furthermore it was established that the type of reflector used for the scintillator has a considerable influence on the response functions. A mechanism for this influence has been proposed and tested by Monte Carlo calculations.

  18. Comments on (n, charged particle) reactions at E/sub n/ = 14 MeV

    International Nuclear Information System (INIS)

    Haight, R.C.

    1984-01-01

    The study of charged particles produced by bombarding materials with 14 MeV neutrons is important for the development of fusion reactors and for biomedical applications as well as for the basic understanding of nuclear reactions. Several experimental techniques for investigating these reactions are discussed here. The interpretation of the data requires the consideration of several possible reaction mechanisms including equilibrium and preequilibrium particle emission and, for light nuclei, sequential particle emission, final state interactions, and the effect of resonances. 17 references

  19. Pt.2. Charge and mass analysis at 217MeV bombarding energy

    International Nuclear Information System (INIS)

    Galin, J.; Gatty, B.; Guerreau, D.; Lefort, M.; Tarrago, X.; Agarwal, S.; Babinet, R.; Cauvin, B.; Girard, J.; Nifenecker, H.

    1977-01-01

    Atomic numbers and masses have been identified for the fragments (12 40 Ar (217MeV) + 197 Au. Even for such a large mass asymmetry in the entrance channel it is shown how difficult it is, for some part of the cross section, to distinguish between a classical deep inelastic phenomenon and the formation of a true compound nucleus followed by symmetric fission. The two reaction mechanisms are then studied separately in a critical way comparing with existing models

  20. High-dose MeV electron irradiation of Si-SiO2 structures implanted with high doses Si+

    Science.gov (United States)

    Kaschieva, S.; Angelov, Ch; Dmitriev, S. N.

    2018-03-01

    The influence was studied of 22-MeV electron irradiation on Si-SiO2 structures implanted with high-fluence Si+ ions. Our earlier works demonstrated that Si redistribution is observed in Si+-ion-implanted Si-SiO2 structures (after MeV electron irradiation) only in the case when ion implantation is carried out with a higher fluence (1016 cm-2). We focused our attention on the interaction of high-dose MeV electron irradiation (6.0×1016 cm-2) with n-Si-SiO2 structures implanted with Si+ ions (fluence 5.4×1016 cm-2 of the same order magnitude). The redistribution of both oxygen and silicon atoms in the implanted Si-SiO2 samples after MeV electron irradiation was studied by Rutherford back-scattering (RBS) spectroscopy in combination with a channeling technique (RBS/C). Our results demonstrated that the redistribution of oxygen and silicon atoms in the implanted samples reaches saturation after these high doses of MeV electron irradiation. The transformation of amorphous SiO2 surface into crystalline Si nanostructures (after MeV electron irradiation) was evidenced by atomic force microscopy (AFM). Silicon nanocrystals are formed on the SiO2 surface after MeV electron irradiation. The shape and number of the Si nanocrystals on the SiO2 surface depend on the MeV electron irradiation, while their size increases with the dose. The mean Si nanocrystals height is 16-20 nm after irradiation with MeV electrons at the dose of 6.0×1016 cm-2.

  1. Forecasting E > 50-MeV Proton Events with the Proton Prediction System (PPS)

    Science.gov (United States)

    Kahler, S. W.; White, S. M.; Ling, A. G.

    2017-12-01

    Forecasting solar energetic (E > 10 MeV) particle (SEP) events is an important element of space weather. While several models have been developed for use in forecasting such events, satellite operations are particularly vulnerable to higher-energy (> 50 MeV) SEP events. Here we validate one model, the proton prediction system (PPS), which extends to that energy range. We first develop a data base of E > 50-MeV proton events > 1.0 proton flux units (pfu) events observed on the GOES satellite over the period 1986 to 2016. We modify the PPS to forecast proton events at the reduced level of 1 pfu and run PPS for four different solar input parameters: (1) all > M5 solar X-ray flares; (2) all > 200 sfu 8800-MHz bursts with associated > M5 flares; (3) all > 500 sfu 8800-MHz bursts; and (4) all > 5000 sfu 8800-MHz bursts. For X-ray flare inputs the forecasted event peak intensities and fluences are compared with observed values. The validation contingency tables and skill scores are calculated for all groups and used as a guide to use of the PPS. We plot the false alarms and missed events as functions of solar source longitude.

  2. A novel source of MeV positron bunches driven by energetic protons for PAS application

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Zongquan, E-mail: tqq1123@mail.ustc.edu.cn [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Xu, Wenzhen; Liu, Yanfen; Xiao, Ran; Kong, Wei [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ye, Bangjiao, E-mail: bjye@ustc.edu.cn [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-11-01

    This paper proposes a novel methodology of MeV positrons generation for PAS application. Feasibility of this proposal analyzed by G4Beamline and Transport have shown reasonable success. Using 2 Hz, 1.6 GeV, 100 ns and 1.5 μC/bunch proton bunches for bombarding a graphite target, about 100 ns e{sup +} bunches are generated. Quasi-monochromatic positrons in the range of 1–10 MeV included in these bunches have a flux of >10{sup 7}/s, peak brightness of 10{sup 14}/s. A magnetic-confinement beamline is utilized to transport the positrons and a “Fast Beam Chopper” is unprecedentedly extended to chop those relativistic bunches. The positron beam can be finally characterized by the energy range of 1–10 MeV and bunch width from one hundred ps up to 1 ns. Such ultrashort bunches can be useful in tomography-type positron annihilation spectroscopy (PAS) as well as other applications.

  3. A novel source of MeV positron bunches driven by energetic protons for PAS application

    Science.gov (United States)

    Tan, Zongquan; Xu, Wenzhen; Liu, Yanfen; Xiao, Ran; Kong, Wei; Ye, Bangjiao

    2014-11-01

    This paper proposes a novel methodology of MeV positrons generation for PAS application. Feasibility of this proposal analyzed by G4Beamline and Transport have shown reasonable success. Using 2 Hz, 1.6 GeV, 100 ns and 1.5 μC/bunch proton bunches for bombarding a graphite target, about 100 ns e+ bunches are generated. Quasi-monochromatic positrons in the range of 1-10 MeV included in these bunches have a flux of >107/s, peak brightness of 1014/s. A magnetic-confinement beamline is utilized to transport the positrons and a "Fast Beam Chopper" is unprecedentedly extended to chop those relativistic bunches. The positron beam can be finally characterized by the energy range of 1-10 MeV and bunch width from one hundred ps up to 1 ns. Such ultrashort bunches can be useful in tomography-type positron annihilation spectroscopy (PAS) as well as other applications.

  4. Observations on late effects in mice exposed to 400 MeV neutrons

    CERN Document Server

    Covelli, V; Bassani, B; Baarli, Johan; Bianchi, M; Metalli, P; Covelli, V; Di Paola, M; Bassani, B; Baarli, J no 2; Bianchi, M no 2; Metalli, P

    1976-01-01

    Life-long observations on mortality and pathology at death were carried out on groups of mice irradiated with 250 kV X-rays or exposed to a 400 MeV neutron beam, both directly and after attenuation corresponding to the maximum dose build-up region, at comparable dose-rates. Doses up to 84 rad of 400 MeV neutrons and up to 200 rad of X-rays showed no effect on the longevity of the animals, which suggests an upper limit to the r.b.e. for life-shortening of approximately 2·5. Similar conclusions were drawn from the data on all types of leukemias. For all other neoplasms, the age-specific death-rate showed a similar shortening of the latency times for groups of mice irradiated with 0–84 rad of 400 MeV direct neutrons and 0–400 rad of X-rays, also suggesting an upper limit to the r.b.e. slightly higher than that previously indicated for life-shortening. No definite effect was observed after exposure to the attenuated neutron beam at the doses used in these experiments.

  5. Generation and application of 15 to 30 MeV parametric X-ray by linac

    CERN Document Server

    Akimoto, T

    2002-01-01

    15 to 30 MeV parametric X-ray (PXR) was generated using Si single crystal by 45 MeV electron LINAC. To obtain good monochromatic hard X-ray field, the appropriate conditions were determined by theoretical analysis and experiments. The intensity of PXR was increased with increasing electron energy and crystal rotation angle. However, PXR energy is independent of electron energy. By increasing measurement angle, energy of PXR decreased, but its intensity increased. 15 to 30 keV PXR energy and about 10 sup - sup 5 to 10 sup - sup 6 photon/electron of intensity were observed at 15 to 22 deg detection angle under the operation conditions of 45 MeV electron energy and 4 to 8 nA of beam current. The mass attenuation coefficient of photon of Zr, Nb and Mo, in K absorption edge was measured. Application to determine lattice distortion of target sample and off-angle of crystal was investigated. Generation and detection of PXR, measurement of characteristic properties: crystal rotation angle, detection angle, electron e...

  6. Simulations of Beam Quality in a 13 MeV PET Cyclotron

    Directory of Open Access Journals (Sweden)

    A. Pramudita

    2015-12-01

    Full Text Available Simulation of the trajectories of negative hydrogen ion (H− beam in a 13 MeV PET cyclotron (DECY-13 were carried out by using the Runge-Kutta (RK4 approximation method and Scilab 5.4.1. The magnetic and electric fields were calculated using Opera-3d/TOSCA softwares at 1 mm resolution. The cyclotron is of a fourth-harmonics type, meaning that the acceleration occurs four times per cycle, with a radiofrequency (RF field of 77.66 MHz frequency and 40 kV amplitude. The calculations and simulations show that the maximum distance between the ion source and the puller is about 6 mm, while the maximum width of the beam at 13 MeV is about 10 mm, and the initial phase between the RF field and the beam ranges from -10° to 10°, with a yield of about 10% of the beam from the ion source getting accelerated to 13 MeV.

  7. Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Katayama, Tadashi; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1993-10-01

    In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (J.P.N.).

  8. Diffusion of alpha-like MeV ions in TFTR

    International Nuclear Information System (INIS)

    Boivin, R.L.; Zweben, S.J.; Chang, C.S.; Hammett, G.; Mynick, H.E.; White, R.B.

    1991-01-01

    Single particle confinement of alpha particles is of crucial importance in reactor-grade tokamaks like BPX and ITER. Besides the well-known process of first-orbit losses, mechanisms that could lead to significant loss of alpha particles are turbulence-induced diffusion and toroidal field ripple stochastic diffusion. These two mechanisms have been separately studied in TFTR using two different detectors (one at the bottom of the machine and the other near the outer midplane) which can detect escaping charged fusion products, namely the 1 MeV triton and the 3 MeV proton in D-D plasmas (and also the 3.5 MeV alpha in D-T). The main difficulty in this type of experiment lies in the necessity of distinguishing the diffusion process from the always-present first-orbit loss-process. In this paper, we show how these two processes can be distinguished using the pitch-angle discrimination of the detectors. The pitch-angle is defined here as the angle of the particle trajectory with respect to the toroidal direction and so is a measure of the ion magnetic moment, μ. Results obtained at the midplane would be the first reported evidence of TF ripple diffusion in a tokamak. (author) 3 refs., 2 figs

  9. Release the beams! - Linac4 ready to hit the 50 MeV mark

    CERN Multimedia

    Katarina Anthony

    2015-01-01

    The Linac4 accelerator is now prepared to reach 50 MeV. This milestone energy - expected in the coming weeks - will allow the machine to act as a replacement for the ageing Linac2, four years before it takes over at the head of the accelerator chain in 2020.    Inside the Linac4 tunnel, the final DTL cavities will guide beams to 50 MeV.  (Image: Stephan Russenschuck.) The Linac4 accelerator will bring H- ion beams (hydrogen atoms with an extra electron) up to 160 MeV for injection into the PS Booster. As a key part of the LHC injector upgrade programme, Linac4 will allow the PS Booster to double its beam brightness, which will contribute to increasing the LHC’s luminosity. Linac4 will soon bring beams up to 50 MeV - the current energy delivered by the Linac2 accelerator. This milestone follows on from another recent accomplishment: the installation and commissioning of the final Drift Tube Linac (DTL) tank. Using an innovati...

  10. Identification and imaging of modern paints using Secondary Ion Mass Spectrometry with MeV ions

    DEFF Research Database (Denmark)

    Bogdanović Radović, Iva; Siketić, Zdravko; Jembrih-Simbürger, Dubravka

    2017-01-01

    Secondary Ion Mass Spectrometry using MeV ion excitation was applied to analyse modern paint materials containing synthetic organic pigments and binders. It was demonstrated that synthetic organic pigments and binder components with molecular masses in the m/z range from 1 to 1200 could be identi......Secondary Ion Mass Spectrometry using MeV ion excitation was applied to analyse modern paint materials containing synthetic organic pigments and binders. It was demonstrated that synthetic organic pigments and binder components with molecular masses in the m/z range from 1 to 1200 could...... be identified in different paint samples with a high efficiency and in a single measurement. Different ways of mounting of mostly insulating paint samples were tested prior to the analysis in order to achieve the highest possible yield of pigment main molecular ions. As Time-of-Flight mass spectrometer for Me......V Secondary Ion Mass Spectrometry is attached to the heavy ion microprobe, molecular imaging on cross-sections of small paint fragments was performed using focused ions. Due to the fact that molecules are extracted from the uppermost layer of the sample and to avoid surface contamination, the paint samples...

  11. Effects produced in GaAs by MeV ion bombardment

    International Nuclear Information System (INIS)

    Wie, C.R.

    1985-01-01

    The first part of this thesis presents work performed on the ionizing energy beam induced adhesion enhancement of thin (approx.500 A) Au films on GaAs substrates. The ionizing beam, employed in the present thesis, is the MeV ions (i.e., 16 O, 19 F, and 35 Cl), with energies between 1 and 20 MeV. Using the Scratch test for adhesion measurement, and ESCA for chemical analysis of the film substrate interface, the native oxide layer at the interface is shown to play an important role in the adhesion enhancement by the ionizing radiation. A model is discussed that explains the experimental data on the dependence of adhesion enhancement on the energy which was deposited into electronic processes at the interface. The second part of the thesis presents research results on the radiation damage in GaAs crystals produced by MeV ions. Lattice parameter dilatation in the surface layers of the GaAs crystals becomes saturated after a high dose bombardment at room temperature. The strain produced by nuclear collisions is shown to relax partially due to electronic excitation (with a functional dependence on the nuclear and electronic stopping power of bombarding ions. Data on the GaAs and GaP crystals suggest that low temperature recovery stage defects produce major crystal distortion

  12. YAP(Ce) crystal characterization with proton beam up to 60 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Randazzo, N. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy)], E-mail: nunzio.randazzo@ct.infn.it; Sipala, V.; Aiello, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy); Lo Presti, D. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); Cirrone, G.A.P.; Cuttone, G.; Di Rosa, F. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud (Italy)

    2008-02-21

    A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ (http://www.lns.infn.it/CATANA/CATANA)] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application.

  13. YAP(Ce) crystal characterization with proton beam up to 60 MeV

    International Nuclear Information System (INIS)

    Randazzo, N.; Sipala, V.; Aiello, S.; Lo Presti, D.; Cirrone, G.A.P.; Cuttone, G.; Di Rosa, F.

    2008-01-01

    A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ (http://www.lns.infn.it/CATANA/CATANA)] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application

  14. YAP(Ce) crystal characterization with proton beam up to 60 MeV

    Science.gov (United States)

    Randazzo, N.; Sipala, V.; Aiello, S.; Lo Presti, D.; Cirrone, G. A. P.; Cuttone, G.; Di Rosa, F.

    2008-02-01

    A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ http://www.lns.infn.it/CATANA/CATANA] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application.

  15. EXPERIMENTAL ANALYSES OF SPALLATION NEUTRONS GENERATED BY 100 MEV PROTONS AT THE KYOTO UNIVERSITY CRITICAL ASSEMBLY

    Directory of Open Access Journals (Sweden)

    CHEOL HO PYEON

    2013-02-01

    Full Text Available Neutron spectrum analyses of spallation neutrons are conducted in the accelerator-driven system (ADS facility at the Kyoto University Critical Assembly (KUCA. High-energy protons (100 MeV obtained from the fixed field alternating gradient accelerator are injected onto a tungsten target, whereby the spallation neutrons are generated. For neutronic characteristics of spallation neutrons, the reaction rates and the continuous energy distribution of spallation neutrons are measured by the foil activation method and by an organic liquid scintillator, respectively. Numerical calculations are executed by MCNPX with JENDL/HE-2007 and ENDF/B-VI libraries to evaluate the reaction rates of activation foils (bismuth and indium set at the target and the continuous energy distribution of spallation neutrons set in front of the target. For the reaction rates by the foil activation method, the C/E values between the experiments and the calculations are found around a relative difference of 10%, except for some reactions. For continuous energy distribution by the organic liquid scintillator, the spallation neutrons are observed up to 45 MeV. From these results, the neutron spectrum information on the spallation neutrons generated at the target are attained successfully in injecting 100 MeV protons onto the tungsten target.

  16. Bias dependent charge trapping in MOSFETs during 1 and 6 MeV electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, N.S. [Department of Chemical Engineering, Mie University, 5148507 (Japan); Kulkarni, V.R.; Mathakari, N.L.; Bhoraskar, V.N. [Department of Physics, Univeristy of Pune, Pune 411007 (India); Dhole, S.D. [Department of Physics, Univeristy of Pune, Pune 411007 (India)], E-mail: sanjay@physics.unipune.ernet.in

    2008-06-15

    To study irradiation-induced charge trapping in SiO{sub 2} and around the SiO{sub 2}-Si interface, depletion n-MOSFETs (metal-oxide-semiconductor field effect transistor) were used. The devices were gate biased during 1 and 6 MeV pulsed electron irradiation. The I{sub D}-V{sub DS} (drain current versus drain voltage) and I{sub D}-V{sub GS} (drain current versus gate voltage) characteristics were measured before and after irradiation. The shift in threshold voltage {delta}V{sub T} (difference in threshold voltage V{sub T} before and after irradiation) exhibited trends depending on the applied gate bias during 1 MeV electron irradiation. This behavior can be associated to the contribution of irradiation-induced negative charge {delta}N{sub IT} buildup around the SiO{sub 2}-Si interface to {delta}V{sub T}, which is sensitive to the electron tunneling from the substrates. However, only weak gate bias dependence was observed in 6 MeV electron irradiated devices. Independent of the energy loss and applied bias, the positive oxide trapped charge {delta}N{sub OT} is marginal and can be associated to thin and good quality of SiO{sub 2}. These results are explained using screening of free and acceptor states by the applied bias during irradiation, thereby reducing the total irradiation-induced charges.

  17. High-quality beam generation using an RF gun and a 150 MeV microtron

    Science.gov (United States)

    Kuroda, R.; Washio, M.; Kashiwagi, S.; Kobuki, T.; Ben-Zvi, I.; Wang, X. J.; Hori, T.; Sakai, F.; Tsunemi, A.; Urakawa, J.; Hirose, T.

    2000-11-01

    Low-emittance sub-picosecond electron pulses are expected to be used in a wide field, such as free electron laser, laser acceleration, femtosecond X-ray generation by Inverse Compton scattering, pulse radiolysis, etc. In order to produce the low-emittance sub-picosecond electron pulse, we are developing a compact Racetrack Microtron (RTM) with a new 5 MeV injection system adopting a laser photo cathode RF gun (Washio et al., Seventh China-Japan Bilateral Symposium on Radiation Chemistry, October 28, Cengdu, China, 1996). The operation of RTM has been kept under a steady state of beam loading for long pulse mode so far (Washio et al., J. Surf. Sci. Soc. Jpn. 19 (2) (1998) 23). In earlier work (Washio et al., PAC99, March 31, New York, USA, 1999), we have succeeded in the numerical simulation for the case of single short pulse acceleration. Finally, the modified RTM was demonstrated as a useful accelerator for a picosecond electron pulse generation under a transient state of beam loading. In the simulation, a picosecond electron pulse was accelerated to 149.6 MeV in RTM for the injection of 5 MeV electron bunch with a pulse length of 10 ps (FWHM), a charge of 1 nC per pulse, and an emittance of 3 πmm mrad.

  18. Equilibration in the reaction of 175 and 252 MeV 20Ne with 197Au

    International Nuclear Information System (INIS)

    Moulton, J.B.

    1978-06-01

    The highly inelastic nuclear reaction of 197 Au with 20 Ne at 175 and 252 MeV laboratory energies is studied. Energy-, elemental-, and angular- distributions for atomic numbers 5 to 30 (175 MeV) or 34 (252 MeV) are presented. The means and widths of the kinetic energy spectra for detected elements are compared with a theoretical calculation. The calculation postulates thermalization of the incident projectile kinetic energy, and includes one sha(e-vibrational degree of freedom and rigid rotation of the reaction complex. The effect of particle evaporation is considered. Good agreement of the expurimental mean energies with the theory is obtained. Poorer agreement of the kinetic energy widths with the theory may be due to a low-temperature quantal effect. The relative elemental yields are analyzed for their degree of equilibration, based on a model of diffusive nucleon exchange as described by the master equation. A similar degree of equilibration is observed for both reaction energies. The absolute elemental yields are reproduced qualitatively by employing an advanced diffusion code, coupled with calculation of the subsequent fission of heavy reaction products, including the compound nucleus. The angular distributions are analyzed with a simple model, to estimate the reaction lifetime of selected elements

  19. Total cross section of 242Pu between 0.7 and 170 MeV

    International Nuclear Information System (INIS)

    Moore, M.S.; Lisowski, P.W.; Morgan, G.L.; Auchampaugh, G.F.

    1979-01-01

    Various evaluations of the neutron cross sections of 242 Pu lead to widely different predictions of bulk neutronics properties such as critical mass. These evaluations also show rather different behavior of the energy dependence of the total cross section. The total cross section of 242 Pu from 0.7 to 170 MeV was measured to a statistical accuracy of = 0.5% below 6 MeV, using 8 g of high purity material and the WNR pulsed neutron facility. Recent evaluations by Madland and Young and by Lagrange and Jary are found to be reasonably consistent with the data obtained. Best agreement, however, is found by using a relationship between the total cross sections for 238 U, 239 Pu, and 235 U. The remarkable accuracy of this description for 242 Pu suggests that it could be extended to other deformed actinides for which inadequate amounts of material exist for direct measurements of sigma/sub T/ in the MeV region, as an evaluation constraint

  20. In vitro activation of bone with 14 MeV neutrons

    International Nuclear Information System (INIS)

    Holmberg, P.; Hyvoenen, M.; Tarvainen, M.

    1978-01-01

    Samples of compact bone, bone marrow and spongiosa of cow femur have been irradiated in vitro with 14 MeV neutrons. The Ca/P ratio for compact bone was found to be 2.16+-0.24. The suitability of using 14 MeV neutrons and the 31 P(n, α) 28 Al reaction for studying the bone mineral composition in vitro is discussed. It was demonstrated that 14 MeV neutrons can be used for the determination of calcium and phosphorus in bone with the aid of the 44 Ca(n, p) 44 K and 31 P(n, α) 28 Al reactions, respectively. As the Ca/P ratio for compact bone is known, the calcium content can be deduced indirectly from a determination of the phosphorus. This method has the advantage of not requiring moderator materials, as in the case when the 48 Ca(n, γ) 49 Ca reaction is employed. The half-life of the 28 Al activity is short (T=2.243 m) so that only short irradiation times are necessary. (T.G.)

  1. Exclusive data-based modeling of neutron-nuclear reactions below 20 MeV

    Science.gov (United States)

    Savin, Dmitry; Kosov, Mikhail

    2017-09-01

    We are developing CHIPS-TPT physics library for exclusive simulation of neutron-nuclear reactions below 20 MeV. Exclusive modeling reproduces each separate scattering and thus requires conservation of energy, momentum and quantum numbers in each reaction. Inclusive modeling reproduces only selected values while averaging over the others and imposes no such constraints. Therefore the exclusive modeling allows to simulate additional quantities like secondary particle correlations and gamma-lines broadening and avoid artificial fluctuations. CHIPS-TPT is based on the formerly included in Geant4 CHIPS library, which follows the exclusive approach, and extends it to incident neutrons with the energy below 20 MeV. The NeutronHP model for neutrons below 20 MeV included in Geant4 follows the inclusive approach like the well known MCNP code. Unfortunately, the available data in this energy region is mostly presented in ENDF-6 format and semi-inclusive. Imposing additional constraints on secondary particles complicates modeling but also allows to detect inconsistencies in the input data and to avoid errors that may remain unnoticed in inclusive modeling.

  2. Study of tapered glass capillary focusing MeV ion beam

    International Nuclear Information System (INIS)

    Gong Zhiyu; Yan Sha; Ma Hongji; Nie Rui; Xue Jianming; Wang Yugang

    2012-01-01

    In recent years, tapered glass capillary ion beam focusing is developing rapidly. It is attractive for simple, compact, low cost and easy use. However, the focusing mechanism for MeV ion beams is still indistinct. We present several experimental results of focusing 2 MeV He + beam. Ion beams were focused by tapered glass capillaries with various outlet inner diameters from several micron to hundred micron. The current densities, angle divergences and energy spectra of the transmitted ion beams are measured. The results proved that 2 MeV He + ions can focused and guided by our capillaries. The energy spectra show that a great part of transmitted ions experienced obvious energy loss, which is different from results of others research groups. We discussed the reason and charged it to the larger incident angle. Considered the incident ions with larger incident angle, the charge will distribute in a layer of micro meter depth in the capillary’s inner wall, but not the surface. The energy loss and many other spectra characters can be explained in this way.

  3. Large scale silver nanowires network fabricated by MeV hydrogen (H+) ion beam irradiation

    International Nuclear Information System (INIS)

    S, Honey; S, Naseem; A, Ishaq; M, Maaza; M T, Bhatti; D, Wan

    2016-01-01

    A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H + ) ion beam irradiation. Ag-NWs are irradiated under H +  ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H + ion beam-induced welding of Ag-NWs at intersecting positions. H +  ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H +  ion beam, and networks are optically transparent. Morphology also remains stable under H +  ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H +  ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices. (paper)

  4. Comprehensive Measurement of Neutron Yield Produced by 62 MeV Protons on Beryllium Target

    International Nuclear Information System (INIS)

    Osipenko, M.; Ripani, M.; Ricco, G.; Alba, R.; Schillaci, M.; Cosentino, L.; Del Zoppo, A.; Di Pietro, A.; Figuera, P.; Finocchiaro, P.; Maiolino, C.; Santonocito, D.; Scuderi, V.; Barbagallo, M.; Colonna, N.; Boccaccio, P.; Esposito, J.; Celentano, A.; Viberti, C.M.; Kostyukov, A.

    2013-06-01

    A low-power prototype of neutron amplifier, based on a 70 MeV, high current proton cyclotron being installed at LNL for the SPES RIB facility, was recently proposed within INFN-E project. This prototype uses a thick Beryllium converter to produce a fast neutron spectrum feeding a sub-critical reactor core. To complete the design of such facility the new measurement of neutron yield from a thick Beryllium target was performed at LNS. This measurement used liquid scintillator detectors to identify produced neutrons by Pulse Shape Discrimination and Time of Flight technique to measure neutron energy in the range 0.5-62 MeV. To extend the covered neutron energy range 3 He detector was used to measure neutrons below 0.5 MeV. The obtained yields were normalized to the charge deposited by the proton beam on the metallic Beryllium target. These techniques allowed to achieve a wide angular coverage from 0 to 150 degrees and to explore almost complete neutron energy interval. (authors)

  5. Measurement of 15 MeV gamma-rays with the Ge cluster detectors of EUROBALL

    CERN Document Server

    Million, B; Camera, F; Brambilla, S; Gadea, A; Giugni, D; Herskind, B; Kmiecik, M; Isocrate, R; Leoni, S; Maj, A; Prelz, F; Wieland, O

    2000-01-01

    A measurement of the response to 15.1 MeV gamma-rays has been made for the Ge cluster detectors in the EUROBALL array. Each cluster detector consists of seven germanium capsules surrounded by a single anticompton shield of BGO. The reaction D( sup 1 sup 1 B,gamma) sup 1 sup 2 C+n at E sub b sub e sub a sub m =19.1 MeV has been employed. The 'adding-back' of signals simultaneously present in the capsules composing each cluster detector has been made on an event by event basis. The intensity in full-energy peak increases by a factor of three as compared to that of the spectrum obtained by summing the individual spectra of the 7 capsules. The pulse height to energy conversion is found to be very linear from few hundreds keV to 15 MeV. The efficiency is discussed relative to that of large volume BaF sub 2 scintillators.

  6. Cross-section calculations for neutron-induced reactions up to 50 MeV

    International Nuclear Information System (INIS)

    Yamamuro, Nobuhiro.

    1996-01-01

    In the field of accelerator development, medium-energy reaction cross-section data for structural materials of accelerator and shielding components are required, especially for radiation protection purposes. For a d + Li stripping reaction neutron source used in materials research, neutron reaction cross sections up to 50 MeV are necessary for the design study of neutron irradiation facilities. The current version of SINCROS-II is able to calculate neutron and proton-induced reaction cross sections up to ∼ 50 MeV with some modifications and extensions of the cross-section calculation code. The production of isotopes when structural materials and other materials are bombarded with neutrons or protons is calculated using a revised code in the SINCROS-II system. The parameters used in the cross-section calculations are mainly examined with proton-induced reactions because the experimental data for neutrons above 20 MeV are rare. The status of medium mass nuclide evaluations for aluminum, silicon, chromium, manganese, and copper is presented. These data are useful to estimate the radiation and transmutation of nuclei in the materials

  7. Linac-beam characterizations at 600 MeV using optical transition radiation diagnostics.

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A. H.

    1998-05-27

    Selected optical diagnostics stations were upgraded in anticipation of low-emittance, bright electron beams from a thermionic rf gun or a photoelectric rf gun on the Advanced Photon Source (APS) injector linac. These upgrades include installation of optical transition radiation (OTR) screens, transport lines, and cameras for use in transverse beam size measurements and longitudinal profile measurements. Using beam from the standard thermionic gun, tests were done at 50 MeV and 400 to 650 MeV. Data were obtained on the limiting spatial ({sigma} {approximately} 200 {micro}m) and temporal resolution (300 ms) of the Chromox (Al{sub 2}O{sub 3} : Cr) screen (250-{micro}n thick) in comparison to the OTR screens. Both charge-coupled device (CCD) and charge-injection device (CID) video cameras were used as well as the Hamamatsu C5680 synchroscan streak camera operating at a vertical deflection rate of 119.0 MHz (the 24th subharmonic of the S-band 2856-MHz frequency). Beam transverse sizes as small as {sigma}{sub x} = 60 {micro}m for a 600-MeV beam and micropulse bunch lengths of {sigma}{sub {tau}}<3 ps have been recorded for macropulse-averaged behavior with charges of about 2 to 3 nC per macropulse. These techniques are applicable to linac-driven, fourth-generation light source R and D experiments including the APS's SASE FEL experiment.

  8. Forecasting E > 50-MeV proton events with the proton prediction system (PPS)

    Science.gov (United States)

    Kahler, Stephen W.; White, Stephen M.; Ling, Alan G.

    2017-11-01

    Forecasting solar energetic (E > 10-MeV) particle (SEP) events is an important element of space weather. While several models have been developed for use in forecasting such events, satellite operations are particularly vulnerable to higher-energy (≥50-MeV) SEP events. Here we validate one model, the proton prediction system (PPS), which extends to that energy range. We first develop a data base of E ≥ 50-MeV proton events >1.0 proton flux units (pfu) events observed on the GOES satellite over the period 1986-2016. We modify the PPS to forecast proton events at the reduced level of 1 pfu and run PPS for four different solar input parameters: (1) all ≥M5 solar X-ray flares; (2) all ≥200 sfu 8800-MHz bursts with associated ≥M5 flares; (3) all ≥500 sfu 8800-MHz bursts; and (4) all ≥5000 sfu 8800-MHz bursts. The validation contingency tables and skill scores are calculated for all groups and used as a guide to use of the PPS. We plot the false alarms and missed events as functions of solar source longitude, and argue that the longitude-dependence employed by PPS does not match modern observations. Use of the radio fluxes as the PPS driver tends to result in too many false alarms at the 500 sfu threshold, and misses more events than the soft X-ray predictor at the 5000 sfu threshold.

  9. Measurement of photon showers in lead produced by electrons of 150 MeV

    International Nuclear Information System (INIS)

    Goeringer, H.; Eyss, H.J. von; Schoch, B.

    1976-01-01

    The photon energy spectra induced by 150 MeV electrons in lead were measured in the energy range from 40 MeV up to the primary electron energy. The target thickness was varied between 0.1 and 2.5 radiation lengths X 0 . The photons were analyzed by use of a technique based on deuteron photodisintegration. Differential and integral shower spectra are presented and compared with Monte Carlo calculations of Nagel and Messel et al., both interpolated to our primary energy of 150 MeV. The measured spectra show good agreement with these Monte Carlo calculations for the thickest target of 2.5X 0 and with calculated bremsstrahlung spectra for the thinnest target of 0.1X 0 . Considerable discrepancies, however, are found for medium target thicknesses in the range 0 . Around the shower maxima, the shower spectra are narrower and the maxima are shifted about 0.3-0.4X 0 to lower target thicknesses, furthermore the number of photons at the shower maxima are up to 50% higher than calculated. (Auth.)

  10. A 14-MeV beam-plasma neutron source for materials testing

    International Nuclear Information System (INIS)

    Futch, A.H.; Coensgen, F.H.; Damm, C.C.; Molvik, A.W.

    1989-01-01

    The design and performance of 14-MeV beam-plasma neutron sources for accelerated testing of fusion reactor materials are described. Continuous production of 14-MeV neutron fluxes in the range of 5 to 10 MW/m 2 at the plasma surface are produced by D-T reactions in a two-component plasma. In the present designs, 14-MeV neutrons result from collisions of energetic deuterium ions created by transverse injection of 150-keV deuterium atoms on a fully ionized tritium target plasma. The beam energy, which deposited at the center of the tritium column, is transferred to the warm plasma by electron drag, which flows axially to the end regions. Neutral gas at high pressure absorbs the energy in the tritium plasma and transfers the heat to the walls of the vacuum vessel. The plasma parameters of the neutron source, in dimensionless units, have been achieved in the 2XIIB high-β plasma. The larger magnetic field of the present design permits scaling to the higher energy and density of the neutron source design. In the extrapolation, care has been taken to preserve the scaling and plasma attributes that contributed to equilibrium, magnetohydrodynamic (MHD) stability, and microstability in 2XIIB. The performance and scaling characteristics are described for several designs chosen to enhance the thermal isolation of the two-component plasmas. 11 refs., 3 figs., 3 tabs

  11. The 2-MEV model: Constancy of adolescent environmental values within an 8-year time frame

    Science.gov (United States)

    Bogner, F. X.; Johnson, B.; Buxner, S.; Felix, L.

    2015-08-01

    The 2-MEV model is a widely used tool to monitor children's environmental perception by scoring individual values. Although the scale's validity has been confirmed repeatedly and independently as well as the scale is in usage within more than two dozen language units all over the world, longitudinal properties still need clarification. The purpose of the present study therefore was to validate the 2-MEV scale based on a large data basis of 10,676 children collected over an eight-year period. Cohorts of three different US states contributed to the sample by responding to a paper-and-pencil questionnaire within their pre-test initiatives in the context of field center programs. Since we used only the pre-program 2-MEV scale results (which is before participation in education programs), the data were clearly unspoiled by any follow-up interventions. The purpose of analysis was fourfold: First, to test and confirm the hypothesized factorized structure for the large data set and for the subsample of each of the three states. Second, to analyze the scoring pattern across the eight years' time range for both preservation and utilitarian preferences. Third, to investigate any age effects in the extracted factors. Finally, to extract suitable recommendations for educational implementation efforts.

  12. Integral activation experiment of fusion reactor materials with d-Li neutrons up to 55 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Maekawa, Fujio; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Moellendorff, Ulrich von [Forschungszentrum Karlsruhe, Karlsruhe (Germany); Wada, Masayuki [Business Automation Co., Ltd., Tokyo (Japan)

    2000-03-01

    An integral activation experiment of fusion reactor materials with a deuteron-lithium neutron source was performed. Since the maximum energy of neutrons produced was 55 MeV, the experiment with associated analysis was one of the first attempts for extending the energy range beyond 20 MeV. The following keywords represent the present study: d-Li neutrons, 55 MeV, dosimetry, SAND-II, spectrum adjustment, LA-150, MCNP, McDeLi, IFMIF, fusion reactor materials, integral activation experiment, low-activation, F82H, vanadium-alloy, IEAF, ALARA, and sequential charged particle reaction. (author)

  13. Measurement of the 19F(n,2n)18F cross section from 18 to 27 MeV

    International Nuclear Information System (INIS)

    Hartmann, C.L.; DeLuca, P.M. Jr.

    1990-01-01

    the 19 F(n,2n) 18 F cross section was measured at neutron energies of 18, 21, 23, and 27 MeV. Nearly monoenergetic neutrons bombarded teflon (CF 2 ), Zr, and Au samples. 19 F(n,2n) 18 F cross section values were determined relative to nat Zr(n,xn) 89 Zr and 197 Au(n,2n) 196 Au from measurements of the 18 F, 89 Zr, and 196 Au activities. Our results are in agreement with previous measurements below 20 MeV and extend the usefulness of this reaction to 27 MeV. 22 refs., 1 fig., 2 tabs

  14. Electromagnetic form factors for the 14.39 and 17.50 MeV levels of 9Be

    International Nuclear Information System (INIS)

    Nascimento, I.C.; Wong, C.F.; Caplan, H.S.

    1974-01-01

    The form factors for the 14.39 and 17.50 MeV levels of 9 Be have been measured for momentum transfer in the range between 0.47 and 1.08 fm -1 . Radiative widths for the transitions and the transition radii were also obtained. The results are consistent with the attribution of an M1 transition to the 14.39 MeV level and an M2 to the 17.50 MeV level [pt

  15. Theoretical calculation of n + {sup 59}Co reaction in energy region up to 100 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Qingbiao, Shen; Baosheng, Yu; Dunjiu, Cai [Chinese Nuclear Data Center, Beijing, BJ (China)

    1996-06-01

    A set of neutron optical potential parameters for {sup 59}Co in energy region of 2{approx}100 MeV was obtained based on concerned experimental data. Various cross sections of n + {sup 59}Co reactions were calculated and predicted. The calculated results show that the activation products {sup 58,57}Co, {sup 59}Fe and {sup 56}Mn are main neutron monitor reaction products for n + {sup 59}Co reaction in energy range up to 100 MeV. {sup 54}Mn production reaction can be a promising neutron monitor reaction in the energy region from 30 to 100 MeV. (6 figs.).

  16. Calibration of a dePangher long counter from 2 keV to 19 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Slaughter, D R; Rueppel, D W [California Univ., Livermore (USA). Lawrence Livermore Lab.

    1977-09-01

    The authors have measured the sensitivity of a dePangher precision long counter (PLC) relative to /sup 7/Li(p,n), T(p,n), and T(d,n) differential cross sections over the neutron energy range 10 keV-19 MeV. Absolute sensitivity at 2 keV is also measured, using a scandium filtered beam at a reactor. Results obtained with errors in the range 5-30% are consistent with the assumption of a nearly constant sensitivity over the range 2 keV-6 MeV, but exhibit a reduction above 12 MeV.

  17. Invariant-mass distributions for the pp{yields}pp{eta} reaction at Q=10 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Moskal, P.; Czerwinski, E.; Klaja, J.; Klaja, P.; Krzemien, W. [Jagellonian University, Institute of Physics, Cracow (Poland); Research Center Juelich, Nuclear Physics Institute, Juelich (Germany); Czyzykiewicz, R. [Jagellonian University, Institute of Physics, Cracow (Poland); University of Silesia, Institute of Physics, Katowice (Poland); Gil, D.; Jarczyk, L.; Kamys, B.; Silarski, M.; Smyrski, J.; Zdebik, J.; Zielinski, M.J. [Jagellonian University, Institute of Physics, Cracow (Poland); Grzonka, D.; Oelert, W.; Ritman, J.; Sefzick, T.; Wuestner, P. [Research Center Juelich, Nuclear Physics Institute, Juelich (Germany); Khoukaz, A.; Taeschner, A.; Zipper, W. [Westfaelische Wilhelms-Universitaet, IKP, Muenster (Germany); Siemaszko, M. [University of Silesia, Institute of Physics, Katowice (Poland); Wolke, M. [SE-751 05 Uppsala University, Department of Physics and Astronomy, Uppsala (Sweden)

    2010-02-15

    Proton-proton and proton-{eta} invariant-mass distributions and the total cross-section for the pp{yields}pp{eta} reaction have been determined near the threshold at an excess energy of Q=10 MeV. The experiment has been conducted using the COSY-11 detector setup and the cooler synchrotron COSY. The determined invariant-mass spectra reveal significant enhancements in the region of low proton-proton relative momenta, similarly as observed previously at higher excess energies of Q=15.5 MeV and Q=40 MeV. (orig.)

  18. Ion tail formation and its effect on 14-MeV neutron generation in D-3He plasmas

    International Nuclear Information System (INIS)

    Matsuura, H.; Nakao, Y.; Kudo, K.

    1992-01-01

    This paper reports on the triton distribution function in D- 3 He plasmas which is distorted from a Maxwellian owing to the presence of a 1.01-MeV birth component. The deuteron-triton reaction rate (i.e., 14-MeV neutron generation rate) in the plasma should be smaller than the values evaluated by assuming a Maxwellian triton distribution. A local Fokker-Planck calculation shows that although the degree of the decrease in 14-MeV neutron generation strongly depends on the plasma conditions and also on the energy loss mechanism, it becomes appreciable in actual burning plasmas

  19. Differential production cross sections for charged particles produced by 590 MeV proton bombardment of thin metal targets

    International Nuclear Information System (INIS)

    Howe, S.D.; Cierjacks, S.; Hino, Y.; Raupp, F.; Rainbow, M.T.; Swinhoe, M.T.; Buth, L.

    1981-01-01

    Differential production cross sections have been measured for the reactions (p,p), (p,d), (p,t) and (p,π+-) using the 590 MeV proton beam at SIN. Here we report measurements made on thin targets of aluminium, niobium, lead, and uranium at laboratory angles of 90 0 and 157 0 . The data were taken over a proton energy range of about 50 MeV to 590 MeV. Differential cross sections are reported along with predictions by the intranuclear-cascade/evaporation model as computed by HETC. (orig.)

  20. Differential cross sections of the pp -> pp pi sup 0 reaction from 310 to 425 MeV

    CERN Document Server

    Zlomanczuk, Yu; Brodowski, W; Calén, H; Clement, H; Dyring, J; Ekström, C; Fäldt, G; Fransson, K; Gustafsson, L; Häggström, S; Hoeistad, B; Johanson, J; Johansson, A; Johansson, T; Kilian, K; Kullander, Sven; Kupsc, A; Marciniewski, P; Morosov, B; Moertsell, A; Oelert, W; Ruber, Roger J M Y; Schuberth, U; Sundberg, P; Shwartz, B A; Stepaniak, J; Sukhanov, A; Turowiecki, A; Wagner, G J; Wilhelmi, Z; Wilkin, C; Zabierowski, J; Zernov, A

    2000-01-01

    Measurements of the differential cross sections of the pp -> pp pi sup 0 reaction at 310, 320, 340, 360, 400 and 425 MeV have been carried out at the CELSIUS storage ring in Uppsala. An attempt has been made to describe the distributions obtained in terms of the five partial waves Ss, Ps, Pp, Sd and Ds. The relative contributions from the different states depend significantly upon the energy. For instance, that of the Ss state drops from about 80% at 310 MeV to around 10% at 425 MeV.