WorldWideScience

Sample records for monochromatic sr beams

  1. A Monochromatic electron neutrino beam

    CERN Document Server

    Lindroos, Mats; Burguet-Castell, J; Espinoza, C

    In the last few years spectacular results have been achieved with the demonstration of non vanishingneutrino masses and flavour mixing. Here, a novel method to create a monochromaticneutrino beam, an old dream for neutrino physics, is described based on the recent discoveryof nuclei with fast decay through electron-capture to Gamow-Teller resonances in super allowedtransitions.

  2. A monochromatized chopped beam of cold neutrons for low background experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bussiere, A. (Lab. de Physique des Particules, 74 - Annecy le Vieux (France)); Grivot, P. (Inst. des Sciences Nucleaires, 38 - Grenoble (France)); Kossakowski, R. (Lab. de Physique des Particules, 74 - Annecy le Vieux (France)); Liaud, P. (Lab. de Physique des Particules, 74 - Annecy le Vieux (France)); Saintignon, P. de (Inst. des Sciences Nucleaires, 38 - Grenoble (France)); Schreckenbach, K. (Inst. Laue-Langevin, 38 - Grenoble (France))

    1993-07-15

    The design and performance of a monochromatized, chopped beam of cold neutrons are described. The beam is particularly suited for experiments where a low level of gamma ray and diffused neutron background is required. (orig.)

  3. Dispersion-free monochromatization method for selecting a single-order harmonic beam

    CERN Document Server

    Takahashi, Eiji J; Ichimaru, Satoshi; Midorikawa, Katsumi

    2015-01-01

    We propose a method to monochromatize multiple orders of high harmonics by using a proper designed multilayer mirror. Multilayer mirrors designed by our concept realize the perfect extraction of a single-order harmonic from multiple-order harmonic beam, and exhibit broadband tenability and high reflectivity in the soft-x-ray region. Furthermore, the proposed monochromatization method can preserve the femtosecond to attosecond pulse duration for the reflected beam. This device is very useful for ultrafast soft x-ray experiments that require high-order harmonic beams, such as femtosecond/attosecond, time-resolved, pump-probe spectroscopy.

  4. Breast tomosynthesis with monochromatic beams: a feasibility study using Monte Carlo simulations

    Science.gov (United States)

    Malliori, A.; Bliznakova, K.; Sechopoulos, I.; Kamarianakis, Z.; Fei, B.; Pallikarakis, N.

    2014-08-01

    The aim of this study is to investigate the impact on image quality of using monochromatic beams for lower dose breast tomosynthesis (BT). For this purpose, modeling and simulation of BT and mammography imaging processes have been performed using two x-ray beams: one at 28 kVp and a monochromatic one at 19 keV at different entrance surface air kerma ranging between 0.16 and 5.5 mGy. Two 4 cm thick computational breast models, in a compressed state, were used: one simple homogeneous and one heterogeneous based on CT breast images, with compositions of 50% glandular-50% adipose and 40% glandular-60% adipose tissues by weight, respectively. Modeled lesions, representing masses and calcifications, were inserted within these breast phantoms. X-ray transport in the breast models was simulated with previously developed and validated Monte Carlo application. Results showed that, for the same incident photon fluence, the use of the monochromatic beam in BT resulted in higher image quality compared to the one using polychromatic acquisition, especially in terms of contrast. For the homogenous phantom, the improvement ranged between 15% and 22% for calcifications and masses, respectively, while for the heterogeneous one this improvement was in the order of 33% for the masses and 17% for the calcifications. For different exposures, comparable image quality in terms of signal-difference-to-noise ratio and higher contrast for all features was obtained when using a monochromatic 19 keV beam at a lower mean glandular dose, compared to the polychromatic one. Monochromatic images also provide better detail and, in combination with BT, can lead to substantial improvement in visualization of features, and particularly better edge detection of low-contrast masses.

  5. Excitation of monochromatic and stable electron acoustic wave by two counter-propagating laser beams

    Science.gov (United States)

    Xiao, C. Z.; Liu, Z. J.; Zheng, C. Y.; He, X. T.

    2017-07-01

    The undamped electron acoustic wave is a newly-observed nonlinear electrostatic plasma wave and has potential applications in ion acceleration, laser amplification and diagnostics due to its unique frequency range. We propose to make the first attempt to excite a monochromatic and stable electron acoustic wave (EAW) by two counter-propagating laser beams. The matching conditions relevant to laser frequencies, plasma density, and electron thermal velocity are derived and the harmonic effects of the EAW are excluded. Single-beam instabilities, including stimulated Raman scattering and stimulated Brillouin scattering, on the excitation process are quantified by an interaction quantity, η =γ {τ }B, where γ is the growth rate of each instability and {τ }B is the characteristic time of the undamped EAW. The smaller the interaction quantity, the more successfully the monochromatic and stable EAW can be excited. Using one-dimensional Vlasov-Maxwell simulations, we excite EAW wave trains which are amplitude tunable, have a duration of thousands of laser periods, and are monochromatic and stable, by carefully controlling the parameters under the above conditions.

  6. Energy dependence of CP-violation reach for monochromatic neutrino beam

    Energy Technology Data Exchange (ETDEWEB)

    Bernabeu, Jose [IFIC, Universitat de Valencia-CSIC, E-46100, Burjassot, Valencia (Spain); Espinoza, Catalina [IFIC, Universitat de Valencia-CSIC, E-46100, Burjassot, Valencia (Spain)], E-mail: m.catalina.espinoza@uv.es

    2008-06-26

    The ultimate goal of future neutrino facilities is the determination of CP violation in neutrino oscillations. Besides |U(e3)|{ne}0, this will require precision experiments with a very intense neutrino source and energy control. With this objective in mind, the creation of monochromatic neutrino beams from the electron capture decay of boosted ions by the SPS of CERN has been proposed. We discuss the capabilities of such a facility as a function of the energy of the boost and the baseline for the detector. We compare the physics potential for two different configurations: (I) {gamma}=90 and {gamma}=195 (maximum achievable at present SPS) to Frejus; (II) {gamma}=195 and {gamma}=440 (maximum achievable at upgraded SPS) to Canfranc. We conclude that the SPS upgrade to 1000 GeV is important to reach a better sensitivity to CP violation iff it is accompanied by a longer baseline.

  7. Optical theorem for two-dimensional (2D) scalar monochromatic acoustical beams in cylindrical coordinates.

    Science.gov (United States)

    Mitri, F G

    2015-09-01

    The optical theorem for plane waves is recognized as one of the fundamental theorems in optical, acoustical and quantum wave scattering theory as it relates the extinction cross-section to the forward scattering complex amplitude function. Here, the optical theorem is extended and generalized in a cylindrical coordinates system for the case of 2D beams of arbitrary character as opposed to plane waves of infinite extent. The case of scalar monochromatic acoustical wavefronts is considered, and generalized analytical expressions for the extinction, absorption and scattering cross-sections are derived and extended in the framework of the scalar resonance scattering theory. The analysis reveals the presence of an interference scattering cross-section term describing the interaction between the diffracted Franz waves with the resonance elastic waves. The extended optical theorem in cylindrical coordinates is applicable to any object of arbitrary geometry in 2D located arbitrarily in the beam's path. Related investigations in optics, acoustics and quantum mechanics will benefit from this analysis in the context of wave scattering theory and other phenomena closely connected to it, such as the multiple scattering by a cloud of particles, as well as the resulting radiation force and torque.

  8. The capabilities of monochromatic EC neutrino beams with the SPS upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza, C; Bernabeu, J [IFIC, Universidad de Valencia-CSIC, E-46100, Burjassot, Valencia (Spain)], E-mail: m.catalina.espinoza@uv.es, E-mail: jose.bernabeu@uv.es

    2008-05-15

    The goal for future neutrino facilities is the determination of the U(e3) mixing and CP violation in neutrino oscillations. This will require precision experiments with a very intense neutrino source and energy control. With this objective in mind, the creation of monochromatic neutrino beams from the electron capture decay of boosted ions by the SPS of CERN has been proposed. We discuss the capabilities of such a facility as a function of the energy of the boost and the baseline for the detector. We conclude that the SPS upgrade to 1000 GeV is crucial to reach a better sensitivity to CP violation iff it is accompanied by a longer baseline. We compare the physics potential for two different configurations: I) {gamma} = 90 and {gamma} = 195 (maximum achievable at present SPS) to Frejus; II) {gamma} = 195 and {gamma} = 440 (maximum achievable at upgraded SPS) to Canfranc. The main conclusion is that, whereas the gain in the determination of U(e3) is rather modest, setup II provides much better sensitivity to CP violation.

  9. Improvement of Image Quality in Transmission Computed Tomography Using Synchrotron Monochromatic X-Ray Sheet Beam

    Science.gov (United States)

    2001-10-25

    7] T. Takeda, M. Kazama, T. Zeniya, T. Yuasa, M. Akiba, A. Uchida, K. Hyodo, T. Akatsuka, M. Ando, and Y. Itai , “Development of a Mono- chromatic X...Uyama (Springer-Verlag, Tokyo), pp. 103-110 (1998). [8] Y. Itai , T. Takeda, T. Akatsuka, T. Maeda, K. Hyodo, A. Uchida, T. Yuasa, M. Kazama, J. Wu...T. Yuasa, K. Hyodo, M. Ando, T. Akatsuka, and Y. Itai , “Performance Study of Monochromatic Synchro- tron X-ray Computed Tomography using a Linear

  10. An alignment method for the ATLAS end-cap TRT detector using a narrow monochromatic X-ray beam

    CERN Document Server

    Åkesson, T; Dixon, N; Dolgoshein, B A; Eerola, Paule Anna Mari; Farthouat, Philippe; Fedin, O; Froidevaux, Daniel; Gavrilenko, I; Hajduk, Z; Hauviller, Claude; Ivanov, V; Ivochkin, V G; Jelamkov, A; Konovalov, S V; Lichard, P; Lundberg, B; Muraviev, S; Nadtochy, A; Nevski, P; Peshekhonov, V D; Platonov, Yu P; Price, M; Romaniouk, A; Shchegelskii, V; Shmeleva, A; Smirnov, A; Smirnov, S; Sosnovtsev, V V

    2001-01-01

    The end-cap transition radiation tracker (TRT), consisting of 36 modules (wheels), is being constructed as a part of the ATLAS Inner Detector at the CERN LHC. This paper describes a method for determining the wire positions inside the straw proportional tubes (SPT), which are the basic building blocks of the ATLAS TRT, with an accuracy of better than 10 mu m. The procedure involves moving a narrow monochromatic X-ray beam across the straw and measuring the counting rate as a function of the position of the X-ray beam in the straw. To achieve this goal, a beam directing device (BDD), providing the possibility to direct the X-ray beam in a chosen direction within some solid angle and supplying an accurate angular measurement system, has been constructed. The results of the wire position measurements performed using this BDD on a full-scale mechanical prototype end-cap wheel of the TRT are presented in this paper. (11 refs).

  11. Station on the SR beam of the VEPP-3 storage ring for the study of macromolecular crystal structure (abstract)

    Science.gov (United States)

    Popov, A. N.; Antson, A. A.; Bondarenko, K. P.; Belyaev, V. V.; Harutunyan, E. G.; Kheiker, D. M.; Sheromov, M. A.; Mytnytchenko, S. V.

    1989-07-01

    The station designed to speed up the collection of integral intensity data from protein and virus crystals is constructed on the SR beam of the VEPP-3 storage ring. A flat triangular Si crystal cut at 8° relative to the (111) plane is used to monochromatize the radiation. The monochromator is placed on the automatic goniometer which allows us to obtain the necessary energy of radiation, to make the adjusting turns and displacements, and to bend the crystal in order to achieve focusing in the horizontal plane. All the mechanical drive units are supplied with position sensors based on multiturn potentiometers. A conventional Arndt-Wonacott rotation camera is used to collect structure information. The station also includes an optical bench which can turn about the axis coinciding with that of the monochromator, and a set of slits to cut the background and to form the beam. The ionization camera serves to adjust the monochromator and to monitor the beam.

  12. New frontiers in nuclear physics with high-power lasers and brilliant monochromatic gamma beams

    Science.gov (United States)

    Gales, S.; Balabanski, D. L.; Negoita, F.; Tesileanu, O.; Ur, C. A.; Ursescu, D.; Zamfir, N. V.

    2016-09-01

    The development of high power lasers and the combination of such novel devices with accelerator technology has enlarged the science reach of many research fields, in particular particle and nuclear physics, astrophysics as well as societal applications in material science, nuclear energy and applications for medicine. The European Strategic Forum for Research Infrastructures has selected a proposal based on these new premises called the Extreme Light Infrastructure (ELI). The ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for nuclear physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW lasers and a Compton back-scattering high-brilliance and intense low-energy gamma beam, a combination of laser and accelerator technology at the frontier of knowledge. This unique combination of beams that are unique worldwide allows us to develop an experimental program in nuclear physics at the frontiers of present-day knowledge as well as society driven applications. In the present paper, the technical description of the facility as well as the new perspectives in nuclear structure, nuclear reactions and nuclear astrophysics will be presented.

  13. Extended optical theorem for scalar monochromatic acoustical beams of arbitrary wavefront in cylindrical coordinates.

    Science.gov (United States)

    Mitri, F G

    2016-04-01

    One of the fundamental theorems in (optical, acoustical, quantum, gravitational) wave scattering is the optical theorem for plane waves, which relates the extinction cross-section to the forward scattering complex amplitude function. In this analysis, the optical theorem is extended for the case of 3D-beams of arbitrary character in a cylindrical coordinates system for any angle of incidence and any scattering angle. Generalized analytical expressions for the extinction, absorption, scattering cross-sections and efficiency factors are derived in the framework of the scalar resonance scattering theory for an object of arbitrary shape. The analysis reveals the presence of an interference scattering cross-section term, which describes interference between the diffracted or specularly reflected inelastic (Franz) waves with the resonance elastic waves. Moreover, an alternate expression for the extinction cross-section, which relates the resonance cross-section with the scattering cross-section for an impenetrable object, is obtained, suggesting an improved method for particle characterization. Cross-section expressions are also derived for known acoustical wavefronts centered on the object, defined as the on-axis case. The extended optical theorem in cylindrical coordinates can be applied to evaluate the extinction efficiency from any object of arbitrary geometry placed on or off the axis of the incident beam. Applications in acoustics, optics, and quantum mechanics should benefit from this analysis in the context of wave scattering theory and other phenomena closely connected to it, such as the multiple scattering by many particles, as well as the radiation force and torque.

  14. Colliding. gamma. e and. gamma gamma. beams based in single-pass e/sup +/e/sup -/ accelerators. Pt. 2. Polarization effects, monochromatization improvement

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, I.F.; Kotkin, G.L.; Serbo, V.G.; Panfil, S.L.; Telnov, V.I.

    Polarization effects are considered in colliding ..gamma..e and ..gamma gamma.. beams, which are proposed to be obtained on the basis of linear e/sup +/e/sup -/ colliders (by backward Compton scattering of laser light on electron beams). It is shown that using electrons and laser photons with helicities lambda and Psub(c), such that lambdaPsub(c) < 0, essentially improves the monochromatization. The characteristic laser flash energy, A/sub 0/, which is necessary to obtain a conversion coefficient k proportional 1 with a definite degree of monochromatization, is considerably less (somestimes by one order of magnitude) in the case 2 lambdaPsub(c) = -1 in contrast to the case lambdaPsub(c) = 0. Simultaneously the luminosities Lsub(..gamma..e) and Lsub(..gamma gamma..) essentially increase. Formulae are obtained which allow one to extract the polarization information about ..gamma..e -> X and ..gamma gamma.. -> X reactions. Perculiarities connected with the specific scheme of the ..gamma.. beam preparation are discussed. Problems of the calibration of the ..gamma..e and ..gamma gamma.. collisions for the polarized beams are discussed.

  15. Can AERONET data be used to accurately model the monochromatic beam and circumsolar irradiances under cloud-free conditions in desert environment?

    Directory of Open Access Journals (Sweden)

    Y. Eissa

    2015-07-01

    Full Text Available Routine measurements of the beam irradiance at normal incidence (DNI include the irradiance originating from within the extent of the solar disc only (DNIS whose angular extent is 0.266° ± 1.7 %, and that from a larger circumsolar region, called the circumsolar normal irradiance (CSNI. This study investigates if the spectral aerosol optical properties of the AERONET stations are sufficient for an accurate modelling of the monochromatic DNIS and CSNI under cloud-free conditions in a desert environment. The data from an AERONET station in Abu Dhabi, United Arab Emirates, and a collocated Sun and Aureole Measurement (SAM instrument which offers reference measurements of the monochromatic profile of solar radiance, were exploited. Using the AERONET data both the radiative transfer models libRadtran and SMARTS offer an accurate estimate of the monochromatic DNIS, with a relative root mean square error (RMSE of 5 %, a relative bias of +1 % and acoefficient of determination greater than 0.97. After testing two configurations in SMARTS and three in libRadtran for modelling the monochromatic CSNI, libRadtran exhibits the most accurate results when the AERONET aerosol phase function is presented as a Two Term Henyey–Greenstein phase function. In this case libRadtran exhibited a relative RMSE and a bias of respectively 22 and −19 % and a coefficient of determination of 0.89. The results are promising and pave the way towards reporting the contribution of the broadband circumsolar irradiance to standard DNI measurements.

  16. Verification of TG-61 dose for synchrotron-produced monochromatic x-ray beams using fluence-normalized MCNP5 calculations

    CERN Document Server

    Brown, Thomas A D; Alvarez, Diane; Matthews, Kenneth L; Ham, Kyungmin; 10.1118/1.4761870

    2012-01-01

    Ion chamber dosimetry is being used to calibrate dose for cell irradiations designed to investigate photoactivated Auger electron therapy at the Louisiana State University CAMD synchrotron facility. This study performed a dosimetry intercomparison for synchrotron-produced monochromatic x-ray beams at 25 and 35 keV. Ion chamber depth-dose measurements in a PMMA phantom were compared with the product of MCNP5 Monte Carlo calculations of dose per fluence and measured incident fluence. Monochromatic beams of 25 and 35 keV were generated on the tomography beamline at CAMD. A cylindrical, air-equivalent ion chamber was used to measure the ionization created in a 10x10x10-cm3 PMMA phantom for depths from 0.6 to 7.7 cm. The American Association of Physicists in Medicine TG-61 protocol was applied to convert measured ionization into dose. Photon fluence was determined using a NaI detector to make scattering measurements of the beam from a thin polyethylene target at angles 30 degrees to 60 degrees. Differential Compto...

  17. Low-energy Coulomb excitation of Sr,9896 beams

    Science.gov (United States)

    Clément, E.; Zielińska, M.; Péru, S.; Goutte, H.; Hilaire, S.; Görgen, A.; Korten, W.; Doherty, D. T.; Bastin, B.; Bauer, C.; Blazhev, A.; Bree, N.; Bruyneel, B.; Butler, P. A.; Butterworth, J.; Cederkäll, J.; Delahaye, P.; Dijon, A.; Ekström, A.; Fitzpatrick, C.; Fransen, C.; Georgiev, G.; Gernhäuser, R.; Hess, H.; Iwanicki, J.; Jenkins, D. G.; Larsen, A. C.; Ljungvall, J.; Lutter, R.; Marley, P.; Moschner, K.; Napiorkowski, P. J.; Pakarinen, J.; Petts, A.; Reiter, P.; Renstrøm, T.; Seidlitz, M.; Siebeck, B.; Siem, S.; Sotty, C.; Srebrny, J.; Stefanescu, I.; Tveten, G. M.; Van de Walle, J.; Vermeulen, M.; Voulot, D.; Warr, N.; Wenander, F.; Wiens, A.; De Witte, H.; Wrzosek-Lipska, K.

    2016-11-01

    The structure of neutron-rich Sr,9896 nuclei was investigated by low-energy safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility, CERN, with the MINIBALL spectrometer. A rich set of transitional and diagonal E 2 matrix elements, including those for non-yrast structures, has been extracted from the differential Coulomb-excitation cross sections. The results support the scenario of a shape transition at N =60 , giving rise to the coexistence of a highly deformed prolate and a spherical configuration in 98Sr, and are compared to predictions from several theoretical calculations. The experimental data suggest a significant contribution of the triaxal degree of freedom in the ground state of both isotopes. In addition, experimental information on low-lying states in 98Rb has been obtained.

  18. Dose-response curve of EBT, EBT2, and EBT3 radiochromic films to synchrotron-produced monochromatic x-ray beams

    CERN Document Server

    Brown, Thomas A D; Alvarez, Diane; Matthews, Kenneth L; Ham, Kyungmin; Dugas, Joseph P; 10.1118/1.4767770

    2012-01-01

    This work investigates the dose-response curves of GAFCHROMIC EBT, EBT2, and EBT3 radiochromic films using synchrotron-produced monochromatic x-ray beams. EBT2 film is being utilized for dose verification in photoactivated Auger electron therapy at the Louisiana State University CAMD synchrotron facility. Monochromatic beams of 25, 30, and 35 keV were generated on the tomography beamline at CAMD. Ion chamber depth-dose measurements were used to determine the dose delivered to films irradiated at depths from 0.7 to 8.5 cm in a 10x10x10-cm3 PMMA phantom. AAPM TG-61 protocol was applied to convert measured ionization into dose. Films were digitized using an Epson 1680 Professional flatbed scanner and analyzed using the net optical density (NOD) derived from the red channel. A dose-response curve was obtained at 35 keV for EBT film, and at 25, 30, and 35 keV for EBT2 and EBT3 films. Calibrations of films for 4 MV x-rays were obtained for comparison using a radiotherapy accelerator at Mary Bird Perkins Cancer Cent...

  19. Dose-response curve of EBT, EBT2, and EBT3 radiochromic films to synchrotron-produced monochromatic x-ray beams

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Thomas A. D.; Hogstrom, Kenneth R.; Alvarez, Diane; Matthews, Kenneth L. II; Ham, Kyungmin; Dugas, Joseph P. [Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809 and Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States); Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States); Center for Advanced Microstructures and Devices, Louisiana State University and A and M College, 6980 Jefferson Highway, Baton Rouge, Louisiana 70806 (United States); Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809 and Department of Physics and Astronomy, Louisiana State University and A and M College, 202 Nicholson Hall, Baton Rouge, Louisiana 70803 (United States)

    2012-12-15

    Purpose: This work investigates the dose-response curves of GAFCHROMIC{sup Registered-Sign} EBT, EBT2, and EBT3 radiochromic films using synchrotron-produced monochromatic x-ray beams. EBT2 film is being utilized for dose verification in photoactivated Auger electron therapy at the Louisiana State University Center for Advanced Microstructures and Devices (CAMD) synchrotron facility. Methods: Monochromatic beams of 25, 30, and 35 keV were generated on the tomography beamline at CAMD. Ion chamber depth-dose measurements were used to determine the dose delivered to films irradiated at depths from 0.7 to 8.5 cm in a 10 Multiplication-Sign 10 Multiplication-Sign 10-cm{sup 3} polymethylmethacrylate phantom. AAPM TG-61 protocol was applied to convert measured ionization into dose. Films were digitized using an Epson 1680 Professional flatbed scanner and analyzed using the net optical density (NOD) derived from the red channel. A dose-response curve was obtained at 35 keV for EBT film, and at 25, 30, and 35 keV for EBT2 and EBT3 films. Calibrations of films for 4 MV x-rays were obtained for comparison using a radiotherapy accelerator at Mary Bird Perkins Cancer Center. Results: The sensitivity (NOD per unit dose) of EBT film at 35 keV relative to that for 4-MV x-rays was 0.73 and 0.76 for doses 50 and 100 cGy, respectively. The sensitivity of EBT2 film at 25, 30, and 35 keV relative to that for 4-MV x-rays varied from 1.09-1.07, 1.23-1.17, and 1.27-1.19 for doses 50-200 cGy, respectively. For EBT3 film the relative sensitivity was within 3% of unity for all three monochromatic x-ray beams. Conclusions: EBT and EBT2 film sensitivity showed strong energy dependence over an energy range of 25 keV-4 MV, although this dependence becomes weaker for larger doses. EBT3 film shows weak energy dependence, indicating that it would be a better dosimeter for kV x-ray beams where beam hardening effects can result in large changes in the effective energy.

  20. QED-based Optical Bloch Equations without electric dipole approximation: A model for a two-level atom interacting with a monochromatic X-ray laser beam

    CERN Document Server

    Zhang, Wen-Zhuo

    2012-01-01

    We derive a set of optical Bloch equations (OBEs) directly from the minimal-coupling Hamiltonian density of the bound-state quantum electrodynamics (bound-state QED). Such optical Bloch equations are beyond the former widely-used ones due to that there is no electric dipole approximation (EDA) on the minimal-coupling Hamiltonian density of the bound-state QED. Then our optical Bloch equations can describe a two-level atom interacting with a monochromatic light of arbitrary wavelength, which are suitable to study the spectroscopy and the Rabi oscillations of two-level atoms in X-ray laser beams since that the wavelength of X-ray is close to an atom to make the electric dipole approximation (EDA) invalid.

  1. Ordered SrTiO3 Nanoripples Induced by Fo cused Ion Beam

    Institute of Scientific and Technical Information of China (English)

    Jiang Wu; Gang Chen; Zhaoquan Zeng; Shibin Li; Xingliang Xu; Zhiming M Wang; Gregory J Salamo

    2012-01-01

    Ordered nanoripples on the niobium-doped SrTiO3 surfaces were fabricated through focused ion beam bombardment. The surface morphology of the SrTiO3 nanoripples was characterized using in situ focused ion beam/scanning electron microscopy. The well-aligned SrTiO3 nanostructures were obtained under optimized ion irradiation conditions. The characteristic wavelength was measured as about 210 nm for different ion beam currents. The relationship between the ion irradiation time and current and SrTiO3 surface morphology was analyzed. The presented method will be an effective supplement for fabrication of SrTiO3 nanostructures that can be used for ferroelectric and electronic applications.

  2. Reconnection Remnants in the Magnetic Cloud of October 18-19, 1995: A Shock, Monochromatic Wave, Heat Flux Dropout and Energetic Ion Beam

    Science.gov (United States)

    Collier, Michael R.; Szabo, A.; Farrell, W.; Slavin, J. A.; Lepping, R. P.; Fitzenreiter, R.; Thompson, B.; Hamilton, D. C.; Gloeckler, G.; Ho, G. C.

    2000-01-01

    Evidence is presented that the WIND spacecraft observed particle and field signatures on October 18-19, 1995 due to reconnection near the footpoints of a magnetic cloud (i.e., between 1 and 5 solar radii). These signatures include: (1) an internal shock traveling approximately along the axis of the magnetic cloud, (2) a simple compression of the magnetic field consistent with the footpoint magnetic fields being thrust outwards at speeds much greater than the solar wind speed, (3) an electron heat flux dropout occurring within minutes of the shock indicating a topological change resulting from disconnection from the solar surface, (4) a very cold 5 keV proton beam and (5) an associated monochromatic wave. We expect that, given observations of enough magnetic clouds, Wind and other spacecraft will see signatures similar to the ones reported here indicating reconnection. However, these observations require the spacecraft to be fortuitously positioned to observe the passing shock and other signatures and will therefore be associated with only a small fraction of magnetic clouds. Consistent with this, a few magnetic clouds observed by Wind have been found to possess internal shock waves.

  3. Characterization of grown-in dislocations in high-quality glucose isomerase crystals by synchrotron monochromatic-beam X-ray topography

    Science.gov (United States)

    Suzuki, Ryo; Koizumi, Haruhiko; Kojima, Kenichi; Fukuyama, Seijiro; Arai, Yasutomo; Tsukamoto, Katsuo; Suzuki, Yoshihisa; Tachibana, Masaru

    2017-06-01

    High quality glucose isomerase (GI) single crystals are grown by using chemical cross-linked seed crystals. The crystal structure is an orthorhombic system in which the molecular arrangement is close to a body-centered cubic (bcc) one. The crystal defects, especially dislocations, in GI crystals are experimentally characterized by synchrotron monochromatic-beam X-ray topography. Two straight dislocations are clearly observed, which originate from the interface between the cross-linked seed crystal and the grown crystal. From the invisibility criterion of the dislocation images, it is experimentally identified that they are close to be of pure edge character with the Burgers vector of [1 1 bar 1] which is typical one in bcc metal crystals. Moreover, bead-like contrasts along the dislocation images and the equal-thickness fringes, related to Pendellösung fringes, at crystal edges are clearly observed, which have never been observed in other protein crystals so far. These contrasts can attributed to the dynamical diffraction effect which has been often observed in high-quality crystals such as Si. Thus it seems that the perfection of GI crystals shown in this paper is extremely high compared with other protein crystals reported so far.

  4. Growth of SrVO{sub 3} thin films by hybrid molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Eaton, Craig; Brahlek, Matthew; Engel-Herbert, Roman, E-mail: rue2@psu.edu [Department of Material Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Moyer, Jarrett A. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Alipour, Hamideh M.; Grimley, Everett D.; LeBeau, James M. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2015-11-15

    The authors report the growth of stoichiometric SrVO{sub 3} thin films on (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} (001) substrates using hybrid molecular beam epitaxy. This growth approach employs a conventional effusion cell to supply elemental A-site Sr and the metalorganic precursor vanadium oxytriisopropoxide (VTIP) to supply vanadium. Oxygen is supplied in its molecular form through a gas inlet. An optimal VTIP:Sr flux ratio has been identified using reflection high-energy electron-diffraction, x-ray diffraction, atomic force microscopy, and scanning transmission electron microscopy, demonstrating stoichiometric SrVO{sub 3} films with atomically flat surface morphology. Away from the optimal VTIP:Sr flux, characteristic changes in the crystalline structure and surface morphology of the films were found, enabling identification of the type of nonstoichiometry. For optimal VTIP:Sr flux ratios, high quality SrVO{sub 3} thin films were obtained with smallest deviation of the lattice parameter from the ideal value and with atomically smooth surfaces, indicative of the good cation stoichiometry achieved by this growth technique.

  5. Status report on the tunable monochromatic gamma—ray source

    Institute of Scientific and Technical Information of China (English)

    M.Bertschy; W.Mondelaers; 等

    1996-01-01

    The tunable monochromatic gamma-ray source at the Ghent 15MeV linac is described.The characteristics of the monochromatic beam are given,and some applications,as the detection of heavy elements in other materials,are presented.

  6. GaAs Core/SrTiO3 Shell Nanowires Grown by Molecular Beam Epitaxy.

    Science.gov (United States)

    Guan, X; Becdelievre, J; Meunier, B; Benali, A; Saint-Girons, G; Bachelet, R; Regreny, P; Botella, C; Grenet, G; Blanchard, N P; Jaurand, X; Silly, M G; Sirotti, F; Chauvin, N; Gendry, M; Penuelas, J

    2016-04-13

    We have studied the growth of a SrTiO3 shell on self-catalyzed GaAs nanowires grown by vapor-liquid-solid assisted molecular beam epitaxy on Si(111) substrates. To control the growth of the SrTiO3 shell, the GaAs nanowires were protected using an arsenic capping/decapping procedure in order to prevent uncontrolled oxidation and/or contamination of the nanowire facets. Reflection high energy electron diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were performed to determine the structural, chemical, and morphological properties of the heterostructured nanowires. Using adapted oxide growth conditions, it is shown that most of the perovskite structure SrTiO3 shell appears to be oriented with respect to the GaAs lattice. These results are promising for achieving one-dimensional epitaxial semiconductor core/functional oxide shell nanostructures.

  7. Fabrication of atomically smooth SrRuO3 thin films by laser molecular beam epitaxy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    High-quality SrRuO3 (SRO) thin films and SrTiO3/SRO bilayer were grown epitaxially on SrTiO3 (STO)(001) substrates by laser molecular beam epitaxy. The results of in situ observation of reflection high-energy electron diffraction and ex situ X-ray diffraction θ -2θ scan indicate that the SRO thin films have good crystallinity. The measurements of atomic force microscopy and scan tunneling microscopy reveal that the surface of the SRO thin film is atomically smooth. The resistivity of the SRO thin film is 300 μΩ·cm at room temperature. Furthermore, the transmission electron microscopy study shows that the interfaces of STO/SRO and SRO/STO are very clear and no interfacial reaction layer was observed. The experimental results show that the SRO thin film is an excellent electrode material for devices based on perovskite oxide materials.

  8. Deceleration of a supersonic beam of SrF molecules to 120 m/s

    CERN Document Server

    Mathavan, S C; Esajas, Q; Hoekstra, S

    2016-01-01

    We report on the deceleration of a beam of SrF molecules from 290 to 120~m/s. Following supersonic expansion, the molecules in the $X^2\\Sigma$ ($v=0$, $N=1$) low-field seeking states are trapped by the moving potential wells of a traveling-wave Stark decelerator. With a deceleration strength of 9.6 km/s$^2$ we have demonstrated the removal of 85 % of the initial kinetic energy in a 4 meter long modular decelerator. The absolute amount of kinetic energy removed is a factor 1.5 higher compared to previous Stark deceleration experiments. The demonstrated decelerator provides a novel tool for the creation of highly collimated and slow beams of heavy diatomic molecules, which serve as a good starting point for high-precision tests of fundamental physics.

  9. Target and orbit feedback simulations of a muSR beam line at BNL

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pile, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-07-28

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. For a dc beam an ideal µSR flux for surface µ+ should be about 40 kHz/mm2. In this report we show how this flux could be achieved in a beam line using the AGS complex at BNL for a source of protons. We also determined that an orbit feedback system with a pair of thin silicon position monitors and kickers would miss the desired flux by at least an order of magnitude, even with perfect time resolution and no multiple scattering.

  10. Assessing electron beam sensitivity for SrTiO3 and La0.7Sr0.3MnO3 using electron energy loss spectroscopy.

    Science.gov (United States)

    Nord, Magnus; Vullum, Per Erik; Hallsteinsen, Ingrid; Tybell, Thomas; Holmestad, Randi

    2016-10-01

    Thresholds for beam damage have been assessed for La0.7Sr0.3MnO3 and SrTiO3 as a function of electron probe current and exposure time at 80 and 200kV acceleration voltage. The materials were exposed to an intense electron probe by aberration corrected scanning transmission electron microscopy (STEM) with simultaneous acquisition of electron energy loss spectroscopy (EELS) data. Electron beam damage was identified by changes of the core loss fine structure after quantification by a refined and improved model based approach. At 200kV acceleration voltage, damage in SrTiO3 was identified by changes both in the EEL fine structure and by contrast changes in the STEM images. However, the changes in the STEM image contrast as introduced by minor damage can be difficult to detect under several common experimental conditions. No damage was observed in SrTiO3 at 80kV acceleration voltage, independent of probe current and exposure time. In La0.7Sr0.3MnO3, beam damage was observed at both 80 and 200kV acceleration voltages. This damage was observed by large changes in the EEL fine structure, but not by any detectable changes in the STEM images. The typical method to validate if damage has been introduced during acquisitions is to compare STEM images prior to and after spectroscopy. Quantifications in this work show that this method possibly can result in misinterpretation of beam damage as changes of material properties.

  11. Monochromatic X-ray propagation in multi-Z media for imaging and diagnostics including Kα Resonance Fluorescence

    Science.gov (United States)

    Westphal, Maximillian; Lim, Sara; Nahar, Sultana; Pradhan, Anil

    2016-05-01

    Aimed at monochromatic X-ray imaging and therapy, broadband, monochromatic, and quasi-monochromatic X-ray sources and propagation through low and high-Z (HZ) media were studied with numerically and experimentally. Monte Carlo simulations were performed using the software package Geant4, and a new code Photx, to simulate X-ray image contrast, depth of penetration, and total attenuation. The data show that monochromatic and quasi-monochromatic X-rays achieve improved contrast at lower absorbed radiation doses compared to conventional broadband 120 kV or CT scans. Experimental quasi-monochromatic high-intensity laser-produced plasma sources and monochromatic synchrotron beam data are compared. Physical processes responsible for X-ray photoexcitation and absorption are numerically modelled, including a novel mechanism for accelerating Kα resonance fluorescence via twin monochromatic X-ray beam. Potential applications are medical diagnostics and high-Z material detection. Acknowledgement: Ohio Supercomputer Center, Columbus, OH.

  12. Superconducting thin films of BiSrCaCuO made by sequential electron beam evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Steinbeck, J.; Anderson, A.C.; Tsauer, B.Y.; Strauss, A.J.

    1989-03-01

    Superconducting thin films of Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub x/ have been made by sequential electron-beam evaporation of multiple layers of Bi and Cu metals and (Sr,Ca)F/sub 2/ on MgO substrates. The films were annealed at high temperature, first in wet O/sub 2/ and then in dry O/sub 2/, and cooled to room temperature in dry O/sub 2/. The resulting films which are -- 1 ..mu..m thick, have transition temperatures of -- 85 K. X-ray diffraction shows that the films are preferentially oriented with their c-axis perpendicular to the MgO substrate. The authors' best film has a zero-resistance temperature of 90 K and critical current densities of 8 x 10/sup 4/ A/cm/sup 2/ at 77 K and 2.5 x 10/sup 5/ A/cm/sup 2/ at 4.2 K.

  13. Dielectric and Structural Properties of SrTiO_3 Thin Films Grown by Laser Molecular Beam Epitaxy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Dielectric and Structural Properties of SrTiO_3 Thin Films Grown by Laser Molecular Beam Epitaxy[1]Hao J H,Gao J,Wang Z,et al.Interface structure and phase of epitaxial SrTi O3(110)thin fil ms grown directly on silicon[J].Appl Phys Lett,2005,87:131908. [2]Hao J H,Gao J,Wang HK.SrTi O3(110)thin fil ms grown directly on different oriented silicon substrates[J].Appl Phys A,2005,81:1233. [3]Aki mov I A,Sirenko A A,Clark A M,et al.Electric-field-induced soft-mode hardening in SrTi O3fil ms[J].Phys Rev Lett...

  14. Dosimetric comparison of electron beam and 9{sup 0}Sr+{sup 90}Y applicator for keloids treatment

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Talita S.; Tada, Ariane; Antonio, Patricia L.; Yoriyaz, Helio, E-mail: tasallesc@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Fernandes, Marco A.R., E-mail: marco@cetea.com.b [UNESP, Botucatu, SP (Brazil). Faculdade de Medicina. Dept. de Dermatologia e Radioterapia Rubiao Junior

    2009-07-01

    Studies have been shown that among several methods that have been used for the treatment of keloids the surgical excision followed by the adjuvant radiotherapy presents the lowest relapsed rate of the injury. In this work a comparative dosimetric study has been performed using a 4 MeV electron beam from a Varian Clinac 2100C linear accelerator at the radiotherapy service of the Hospital das Clinicas of UNESP-HC, Botucatu-SP and an Amershan {sup 90}Sr+{sup 90}Y brachytherapy applicator with 1491 MBq of activity. Percentage depth dose curves from ionization chamber measurements and through Monte Carlo simulation have been obtained and compared. Dose measurements have been obtained using parallel plates ionization chamber (Esradin A12) and extrapolation mini-chamber developed at IPEN. The dose calculations have been obtained using the well-known Monte Carlo radiation transport code MCNP-4C. Maximum dose differences obtained between measured/calculated values for {sup 90}Sr+{sup 90}Y applicator and for the electron beam were, respectively: 7.8 % and 8.0%. The profiles of the depth and superficial tissue dose distribution produced by the electron beam revealed themselves flatter and more homogeneous than those produced by the {sup 90}Sr+{sup 90}Y applicator, especially to wider fields, which cannot be obtained with beta therapy applicators because of their geometric limitations. In conclusion this present work has shown that {sup 90}Sr+{sup 90}Y applicators could be efficient for small and very superficial lesions but in most cases electron beam sources are more adequate especially for large and deeper lesions. (author)

  15. Influence of electron beam irradiation on the structural, electrical and thermal properties of Gd0.5Sr0.5MnO3 and Dy0.5Sr0.5MnO3 manganites

    Science.gov (United States)

    Nagaraja, B. S.; Rao, Ashok; Babu, P. D.; Sanjeev, Ganesh; Okram, G. S.

    2016-01-01

    We present systematic studies on the effect of electron beam irradiation on structural, electrical and thermal properties of Gd0.5Sr0.5MnO3 and Dy0.5Sr0.5MnO3 manganites. The XRD patterns and Rietveld analysis show that the samples remain single phased even after they undergo electron beam irradiation. Both the series of the samples Gd0.5Sr0.5MnO3 and Dy0.5Sr0.5MnO3 show insulating trends in their temperature dependent electrical resistivity, ρ(T) behavior. The resistivity data for both the series of samples (pristine as well as irradiated) indicate that the small polaron hopping model is valid in high temperature region; on contrary, variable range hopping model governs the low temperature regime. Magnetic studies demonstrate that the Neel temperatures of pristine and irradiated samples of Gd0.5Sr0.5MnO3 and Dy0.5Sr0.5MnO3 do not change appreciably when they are subjected to irradiation. Thermo-electrical power is observed to increase with irradiation in Gd0.5Sr0.5MnO3 samples, whereas for Dy0.5Sr0.5MnO3 samples a decrease in thermo-electric power is seen when the samples are irradiated.

  16. Preparation of superconducting Bi-Sr-Ca-Cu-O thin films by sequential electron beam evaporation and oxygen annealing

    Energy Technology Data Exchange (ETDEWEB)

    Steinbeck, J.; Tsaur, B.; Anderson, A.C.; Strauss, A.J.

    1989-01-30

    Superconducting films with nominal composition Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub x/ have been prepared on <100> MgO substrates by sequential electron beam evaporation of Cu, Bi, and Sr/sub 2/3/ Ca/sub 1/3/ F/sub 2/, followed by annealing in flowing wet, then dry, O/sub 2/. X-ray diffraction data show that the films contain the two Bi-Sr-Ca-Cu-O phases that have been identified in the literature as a superconducting phase with capprox.31 A and a semiconducting phase with capprox.24 A. Both phases are strongly textured with the c axis perpendicular to the substrate. For the best film, which was annealed at 870 /sup 0/C for 30 min, zero resistance was observed at 90 K, and the critical current density increased from 0.8 x 10/sup 5/ A/cm/sup 2/ at 77 K to 2.3 x 10/sup 5/ A/cm/sup 2/ at 4.2 K.

  17. Evolution of beam losses after a power cut of the SR7 AC supply

    CERN Document Server

    GOMEZ ALONSO, A

    2009-01-01

    Magnet failures in the LHC could lead to equipment damage if the energy stored in the accelerator was not discharged properly. The Machine Protection Systems (MPS) ensure this proper discharge and knowledge about the evolution of losses in case of failure is needed to evaluate the adequacy of the protection. A power cut of the AC supply in SR7 would lead to a simultaneous current decay in three normal conducting circuits. The evolution of the losses after such failure is slow, with a loss time constant of more than 100 ms both at 450 GeV and 7 TeV, and in both cases the damage level is not reached before 45 ms. This leaves sufficient time for the MPS to ensure redundant protection. A similar scenario would be expected for a power cut at SR3.

  18. Laser Molecular Beam Epitaxy of Multilayer Heterostructure SrNb0.05 Ti0.95O3/La0.9Sr0.1MnO3 in 10000 Unit-Cell Layers

    Institute of Scientific and Technical Information of China (English)

    HUANG Yan-Hong; HE Meng; TIAN Huan-Fang; ZHAO Kun; L(U) Hui-Bin; JIN Kui-Juan; LI Jian-Qi; YANG Guo-Zhen

    2008-01-01

    Ten thousands of unit-cell multilayer heterosturctures, [SrNb0.05 Ti0.95 O3/La0.9Sr0.1MnO3]3 (SNTO/LSMO),have been epitaxial grown on SrTiO3 (001) substrates by laser molecular beam epitaxy. The monitor of insitu reflection high-energy electron diffraction demonstrates that the heterosturctures are layer-by-layer epitaxial growth. Atomic force microscope observation indicates that the surface of the heterosturcture is atomically smooth. The measurements of cross-sectional low magnification and high-resolution transmission electron microscopy as well as the corresponding selected area electron diffraction reveal that the interfaces are of perfect orientation, and the epitaxial crystalline structure shows the orientation relation of SNTO(001)//LSMO(001),and SNTO[100]//LSMO[100].

  19. Pulsed electron beam excited transient absorption in SrTiO sub 3

    CERN Document Server

    Millers, D; Pankratov, V V; Trepakov, V A; Kapphan, S E

    2002-01-01

    Transient absorption (TA) spectra and optical density relaxation kinetics in SrTiO sub 3 (STO), STO-Nb and STO-V were studied. The electron polaron free or bound at intrinsic defect is suggested to be responsible for the TA band at approx 1.4 eV observed in STO. The band peaking below 0.75 eV in STO-Nb is proposed to be from Nb sup 4 sup +. The electron center V sup 3 sup + or electron polaron bound in the vicinity of V sup 4 sup + is responsible for the absorption band at 1.0 eV in STO-V. The absorption from hole polarons is suggested to be in the range 1.8-2.3 eV. It is shown that TA in pure STO at room temperature decays due to electron-hole polaron recombination.

  20. Monochromatic gamma emitter for low energy quanta

    CERN Document Server

    Tomova, Z R; Mironova, S A

    2004-01-01

    The possibility of creating of a monochromatic gamma emitter of low energy quanta is analyzed. The idea is based on Daning's scheme. Except for purely scientific problems the monochromator is actual for therapy of wide range of diseases.

  1. System of primary collimators of SR beam at the small-angle station for KSRS

    CERN Document Server

    Ariskin, N I; Korneev, V N; Sergienko, P M; Shishkov, V I; Sheromov, M A; Stankevich, V G; Vazina, A A

    2001-01-01

    The wide program of development of methods and experimental techniques for usage at the Kurchatov Synchrotron Radiation Source (KSRS) is implemented by us. The report illustrates a part of this program directed at creating the small-angle station DICSI-6 on the beam line 'Siberia-2'. It is intended for X-ray diffraction research of structures and structural changes of a wide range of objects in various areas of science and technology--molecular and cell biology, organic chemistry, solid-state physics, etc. Some technical information about the elaborated system of devices for station DICSI-6 intended for forming an X-ray synchrotron beam and method for adjustment of the system are considered.

  2. Ion beam codeposition of HTSC films on SrTiO3 and ITO/Si

    Science.gov (United States)

    Pavuna, Davor; Kellett, Bruce J.; Dwir, Benjamin; James, Jonathan H.; Gauzzi, Andrea; Faulkner, James R., Jr.; Affronte, M.; Reinhardt, F. K.

    1990-10-01

    Superconducting YBa2C u 3 0 7 (YBCO) thin films were grown on Si with transparent, conducting Indium Tin Oxide (ITO) buffer layers The onset temperature at 92K and zero resistance at 68K were measured. Both, ITO and YBCO films were deposited by ion beam co-deposition. The YBCO/ITO films exhibit metallic resistivity with positive slopes (r0.055 1K). The YBCO is uniform, textured and polycrystalline. The relevance for hybrid opto-electronic device structures is briefly discussed.

  3. The monochromatic imaging mode of a RITA-type neutron spectrometer

    DEFF Research Database (Denmark)

    Bahl, C.R.H.; Andersen, P.; Klausen, S.N.;

    2004-01-01

    The imaging monochromatic mode of a neutron spectrometer with a multi-bladed RITA analyser system is so far unexplored. We present analytical calculations that define the mode. It is shown that the mode can be realised for PG (002) analyser crystals, from incident energies of about 3.2 meV and up......, allowing the important cases of 3.7, 5.0 and 13.7 meV. Due to beam divergence, the neutron rays from neighbouring analyser blades are found to overlap slightly. Hence, the optimal use of the monochromatic imaging mode would be found by employing an adjustable radial collimator to limit the spread...

  4. Contrast imaging with a monochromatic x-ray scanner

    Science.gov (United States)

    Pole, Donald J.; Popovic, Kosta; Williams, Mark B.

    2008-03-01

    We are currently developing a monochromatic x-ray source for small animal tomographic imaging. This source consists of a conventional cone beam microfocus x-ray tube with a tungsten target coupled to a filter that uses Bragg diffraction to transmit only x-rays within a narrow energy range (~3 keV FWHM). A tissue-equivalent mouse phantom was used to a) evaluate how clearly CT imaging using the quasi-monoenergetic beam is able to differentiate tissue types compared to conventional polyenergetic CT, and b) to test the ability of the source and Bragg filter combination to perform dual energy, iodine contrast enhanced imaging. Single slice CT scans of the phantom were obtained both with polyenergetic (1.8 mm Al filtration) and quasi-monoenergetic beams. Region of interest analysis showed that pixel value variance was signifcantly reduced in the quasi-monochromatic case compared to the polyenergetic case, suggesting a reduction in the variance of the linear attenuation coefficients of the tissue equivalent materials due to the narrower energy spectrum. To test dual energy iodine K-edge imaging, vials containing solutions with a range of iodine contrasts were added to the phantom. Single-slice CT scans were obtained using spectra with maximum values at 30 and 35 keV, respectively. Analysis of the resulting difference images (35 keV image - 30 keV image) shows that the magnitude of the difference signal produced by iodine exceeds that of bone for iodine concentrations above ~20 mg/ml, and that of muscle and fat tissues for iodine concentrations above ~5 mg/ml.

  5. Effect of Electron Beam Irradiation on Structural, Electrical and Thermo-electric Power of La0.8Sr0.2MnO3

    Directory of Open Access Journals (Sweden)

    Ashok Rao

    2015-03-01

    Full Text Available In this communication, we are reporting the effect of electron beam (e-beam irradiation on thermoelectric properties of La0.8Sr0.2MnO3 manganites. The samples were prepared using solid state reaction technique. It is observed that the lattice volume increases with increase in dosage of e-beam. With irradiation an increase in resistivity is observed. For small irradiation dosage, we first observe a decreases in metal-insulator transition temperature TMI; thereafter TMI increases with further increase in dosage of irradiation. Both, the resistivity data and thermo-electric power data demonstrate that small polaron hopping model is valid in high temperature region.

  6. Transmission electron microscopy study of focused ion beam damage in small intrinsic Josephson junctions of single crystalline Bi2Sr2CaCu2O y

    Science.gov (United States)

    Kakizaki, Yoshihiro; Koyama, Junpei; Yamaguchi, Ayami; Umegai, Shunpei; Ayukawa, Shin-ya; Kitano, Haruhisa

    2017-04-01

    We report a transmission electron microscopy (TEM) study on the damage produced by the focused ion beam (FIB) etching for small Bi2Sr2CaCu2O y (Bi2212) intrinsic Josephson junctions (IJJs). The selected area diffraction patterns of TEM images demonstrate that the FIB damage causes the formation of an amorphous layer. The thickness of FIB damage is at least 30 nm for the Ga+ ion beam emitted at 50 pA and 30 kV, independent of the incident direction of the Ga+ ion beam. We also confirmed that the damage or the redeposition due to the FIB etching was effectively removed by the additional irradiation of Ar ions after the FIB etching. This suggests the advantage of the combinatorial method of the FIB and Ar-ion etchings in the successful fabrication of small and high-quality IJJs.

  7. Laser molecular-beam epitaxy and second-order optical nonlinearity of BaTiO3/SrTiO3 superlattices

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A series of c-axis oriented BaTiO3/SrTiO3 superlattices with the atomic-scale precision were epitaxially grown on single-crystal SrTiO3 (100) substrates using laser molecular-beam epitaxy (LMBE). A periodic modulation of the intensity of reflection high-energy electron diffraction (RHEED) in BaTiO3 and SrTiO3 layers was observed and attributed to the lattice-misfit-induced periodic variation of the terrace density in film surface. The relationship between the second-order nonlinear optical susceptibilities and the superlattice structure was systematically studied. The experimental and theoretical fitting results indicate that the second-order nonlinear optical susceptibilities of BaTiO3/SrTiO3 superlattices were greatly enhanced with the maximum value being more than one order of magnitude larger than that of bulk BaTiO3 crystal. The mechanism of the enhancement of the second-order optical nonlinearity was discussed by taking into account the stress-induced lattice distortion and polarization enhancement.

  8. First Sub-arcsecond Collimation of Monochromatic Neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Wagh, Apoorva G; Abbas, Sohrab; Treimer, Wolfgang, E-mail: nintsspd@barc.gov.in

    2010-11-01

    We have achieved the tightest collimation to date of a monochromatic neutron beam by diffracting neutrons from a Bragg prism, viz. a single crystal prism operating in the vicinity of Bragg incidence. An optimised silicon {l_brace}111{r_brace} Bragg prism has collimated 5.26A neutrons down to 0.58 arcsecond. In conjunction with a similarly optimised Bragg prism analyser of opposite asymmetry, this ultra-parallel beam yielded a 0.62 arcsecond wide rocking curve. This beam has produced the first SUSANS spectrum in Q {approx} 10{sup -6} A{sup -1} range with a hydroxyapatite casein protein sample and demonstrated the instrument capability of characterising agglomerates upto 150 {mu}m in size. The super-collimation has also enabled recording of the first neutron diffraction pattern from a macroscopic grating of 200 {mu}m period. An analysis of this pattern yielded the beam transverse coherence length of 175 {mu}m (FWHM), the greatest achieved to date for A wavelength neutrons.

  9. Feasibility of Strong and Quasi-Monochromatic Gamma-Ray Generation by the Laser Compton Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jiyoung; Rehman, Haseeb ur; Kim, Yonghee [KAIST, Daejeon (Korea, Republic of)

    2015-10-15

    This is because LCS γ-rays are energy-tunable, quasi-monochromatic, and beam-like. The photon intensity of the mono-chromatic LCS gamma-ray should be high or strong for efficient and high transmutation rate. It was recently reported that a so-called energy-recovery linac system is able to produce a very high-intensity LCS photons in the order of approximately 1013 photons/s economically. It however did not evaluate quality of the LCS photon beam although a quasi-monoenergetic LCS beam is of huge importance in the photo-nuclear transmutation reactions. It is upon this observation that this paper was prepared. Specifically, this work attempts to quantify intensity of the quasi-monochromatic LCS beam from the said linac system. In addition, this paper aims to discuss general characteristics of the LCS photon, and possible approaches to increase its intensity. This paper presents essential characteristics of the laser Compton scattering (LCS) in terms of its photon energy, cross-section and photon intensity. By using different combinations of electron energy, laser energy and scattering angle, we can effectively generate high-intensity and highly-chromatic LCS gamma-rays. Our preliminary analyses indicate that, in view of Compton cross-section, higher-energy photon can be better generated by increasing the electron energy rather than increasing the laser energy. However, in order to maximize the intensity of monochromatic beam, the laser energy should be maximized for a targeted LCS photon energy.

  10. Electric field-tunable BaxSr1-xTiO3 films with high figures of merit grown by molecular beam epitaxy

    Science.gov (United States)

    Mikheev, Evgeny; Kajdos, Adam P.; Hauser, Adam J.; Stemmer, Susanne

    2012-12-01

    We report on the dielectric properties of BaxSr1-xTiO3 (BST) films grown by molecular beam epitaxy on epitaxial Pt bottom electrodes. Paraelectric films (x ≲ 0.5) exhibit dielectric losses that are similar to those of BST single crystals and ceramics. Films with device quality factors greater than 1000 and electric field tunabilities exceeding 1:5 are demonstrated. The results provide evidence for the importance of stoichiometry control and the use of a non-energetic deposition technique for achieving high figures of merit of tunable devices with BST thin films.

  11. Towards a Monochromatization Scheme for Direct Higgs Production at FCC-ee

    CERN Document Server

    Valdivia Garcia, Marco Alan; Zimmermann, Frank

    2016-01-01

    Direct Higgs production in e+e− collisions at the FCC is of interest if the centre-of-mass energy spread can be reduced by at least an order of magnitude. A monochromatization scheme, to accomplish this, can be realized with horizontal dispersion of opposite sign for the two colliding beams at the interaction point (IP). We recall historical approaches to monochromatization, then derive a set of IP parameters which would provide the required performance in FCC e+e− collisions at 62.5 GeV beam energy, compare these with the baseline optics parameters at neighbouring energies (45.6 and 80 GeV), comment on the effect of beamstrahlung, and indicate the modifications of the FCC-ee final-focus optics needed to obtain the required parameters.

  12. Determining contrast sensitivity functions for monochromatic light emitted by high-brightness LEDs

    Science.gov (United States)

    Ramamurthy, Vasudha; Narendran, Nadarajah; Freyssinier, Jean Paul; Raghavan, Ramesh; Boyce, Peter

    2004-01-01

    Light-emitting diode (LED) technology is becoming the choice for many lighting applications that require monochromatic light. However, one potential problem with LED-based lighting systems is uneven luminance patterns. Having a uniform luminance distribution is more important in some applications. One example where LEDs are becoming a viable alternative and luminance uniformity is an important criterion is backlighted monochromatic signage. The question is how much uniformity is required for these applications. Presently, there is no accepted metric that quantifies luminance uniformity. A recent publication proposed a method based on digital image analysis to quantify beam quality of reflectorized halogen lamps. To be able to employ such a technique to analyze colored beams generated by LED systems, it is necessary to have contrast sensitivity functions (CSFs) for monochromatic light produced by LEDs. Several factors including the luminance, visual field size, and spectral power distribution of the light affect the CSFs. Although CSFs exist for a variety of light sources at visual fields ranging from 2 degrees to 20 degrees, CSFs do not exist for red, green, and blue light produced by high-brightness LEDs at 2-degree and 10-degree visual fields and at luminances typical for backlighted signage. Therefore, the goal of the study was to develop a family of CSFs for 2-degree and 10-degree visual fields illuminated by narrow-band LEDs at typical luminances seen in backlighted signs. The details of the experiment and the results are presented in this manuscript.

  13. Electron-beam induced disorder effects in optimally doped Bi2Sr2CaCu2O8+x single crystal samples

    Science.gov (United States)

    Vobornik, I.; Berger, H.; Pavuna, D.; Margaritondo, G.; Forro, L.; Grioni, M.; Rullier-Albenque, F.; Onellion, M.; EPFL Collaboration; Laboratoire Des Solides Irradiés Collaboration

    2000-03-01

    We report on the effects of electron-beam induced disorder in optimally doped Bi2Sr2CaCu2O8+x single crystal samples, measured with angle-resolved photoemission. In the superconducting state, the disorder fills in the gap, without changing the binding energy or the width of the narrow coherent feature.[1] In the normal state, disorder leads to an anisotropic pseudogap in angle-resolved photoemission, with the largest pseudogap near the (0,p) point and no pseudogap in the direction.[2,3] We discuss implications of these data. 1. I. Vobornik et.al., Phys. Rev. Lett. 82 , 3128 (1999). 2. I. Vobornik, Ph.D. thesis, EPFL, Lausanne, Switzerland, October, 1999. 3. I. Vobornik et.al., unpublished.

  14. Tailoring medium energy proton beam to induce low energy nuclear reactions in ⁸⁶SrCl₂ for production of PET radioisotope ⁸⁶Y.

    Science.gov (United States)

    Medvedev, Dmitri G; Mausner, Leonard F; Pile, Philip

    2015-07-01

    This paper reports results of experiments at Brookhaven Linac Isotope Producer (BLIP) aiming to investigate effective production of positron emitting radioisotope (86)Y by the low energy (86)Sr(p,n) reaction. BLIP is a facility at Brookhaven National Laboratory designed for the proton irradiation of the targets for isotope production at high and intermediate proton energies. The proton beam is delivered by the Linear Accelerator (LINAC) whose incident energy is tunable from 200 to 66 MeV in approximately 21 MeV increments. The array was designed to ensure energy degradation from 66 MeV down to less than 20 MeV. Aluminum slabs were used to degrade the proton energy down to the required range. The production yield of (86)Y (1.2+/-0.1 mCi (44.4+/-3.7) MBq/μAh) and ratio of radioisotopic impurities was determined by assaying an aliquot of the irradiated (86)SrCl2 solution by gamma spectroscopy. The analysis of energy dependence of the (86)Y production yield and the ratios of radioisotopic impurities has been used to adjust degrader thickness. Experimental data showed substantial discrepancies in actual energy propagation compared to energy loss calculations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Monochromatization of femtosecond XUV light pulses with the use of reflection zone plates.

    Science.gov (United States)

    Metje, Jan; Borgwardt, Mario; Moguilevski, Alexandre; Kothe, Alexander; Engel, Nicholas; Wilke, Martin; Al-Obaidi, Ruba; Tolksdorf, Daniel; Firsov, Alexander; Brzhezinskaya, Maria; Erko, Alexei; Kiyan, Igor Yu; Aziz, Emad F

    2014-05-05

    We report on a newly built laser-based tabletop setup which enables generation of femtosecond light pulses in the XUV range employing the process of high-order harmonic generation (HHG) in a gas medium. The spatial, spectral, and temporal characteristics of the XUV beam are presented. Monochromatization of XUV light with minimum temporal pulse distortion is the central issue of this work. Off-center reflection zone plates are shown to be advantageous when selection of a desired harmonic is carried out with the use of a single optical element. A cross correlation technique was applied to characterize the performance of the zone plates in the time domain. By using laser pulses of 25 fs length to pump the HHG process, a pulse duration of 45 fs for monochromatized harmonics was achieved in the present setup.

  16. Influence of electron beam irradiation on electrical, structural, magnetic and thermal properties of Pr0.8Sr0.2MnO3 manganites

    Science.gov (United States)

    Christopher, Benedict; Rao, Ashok; Petwal, Vikash Chandra; Verma, Vijay Pal; Dwivedi, Jishnu; Lin, W. J.; Kuo, Y.-K.

    2016-12-01

    In this communication, the effect of electron beam (EB) irradiation on the structural, electrical transport and thermal properties of Pr0.8Sr0.2MnO3 manganites has been investigated. Rietveld refinement of XRD data reveals that all samples are single phased with orthorhombic distorted structure (Pbnm). It is observed that the orthorhombic deformation increases with EB dosage. The Mn-O-Mn bond angle is found to increase with increase in EB dosage, presumably due to strain induced by these irradiations. Analysis on the measured electrical resistivity data indicates that the small polaron hopping model is operative in the high temperature region for pristine as well as EB irradiated samples. The electrical resistivity in the entire temperature region has been successfully fitted with the phenomenological percolation model which is based on phase segregation of ferromagnetic metallic clusters and paramagnetic insulating regions. The Seebeck coefficient (S) of the pristine as well as the irradiated samples exhibit positive values, indicating that holes is the dominant charge carriers. The analysis of Seebeck coefficient data confirms that the small polaron hopping mechanism governs the thermoelectric transport in the high temperature region. In addition, Seebeck coefficient data also is well fitted with the phenomenological percolation model. The behavior in thermal conductivity at the transition is ascribed to the local anharmonic distortions associated with small polarons. Specific heat measurement indicates that electron beam irradiation enhances the magnetic inhomogeneity of the system.

  17. Production of BiPbSrCaCuO thin films on MgO and Ag/MgO substrates by electron beam deposition techniques

    CERN Document Server

    Varilci, A; Gorur, O; Celebi, S; Karaca, I

    2002-01-01

    Superconducting BiPbSrCaCuO thin films were prepared on MgO(001) and Ag/MgO substrates using an electron beam (e-beam) evaporation technique. The effects of annealing temperature and Ag diffusion on the crystalline structure and some superconducting properties, respectively, were investigated by X-ray diffraction, atomic force microscopy, and by measurements of the critical temperature and the critical current density. It was shown that an annealing of both types of films at 845 or 860 C resulted in the formation of mixed Bi-2223 and Bi-2212 phases with a high degree of preferential orientation with the c-axis perpendicular to the substrates. The slight increase of the critical temperature from 103 K to 105 K, the enhancement of the critical current density from 2 x 10 sup 3 to 6 x 10 sup 4 A/cm sup 2 , and the improved surface smoothness are due to a possible silver doping from the substrate. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  18. Influence of electron beam irradiation on the structural, electrical and thermal properties of Gd{sub 0.5}Sr{sub 0.5}MnO{sub 3} and Dy{sub 0.5}Sr{sub 0.5}MnO{sub 3} manganites

    Energy Technology Data Exchange (ETDEWEB)

    Nagaraja, B.S. [Department of Physics, Manipal Institute of Technology, Manipal University, Manipal 576104 (India); Rao, Ashok, E-mail: ashokanu_rao@rediffmail.com [Department of Physics, Manipal Institute of Technology, Manipal University, Manipal 576104 (India); Babu, P.D. [UGC-DAE Consortium for Scientific Research, Mumbai Centre, BARC, Mumbai 400085 (India); Sanjeev, Ganesh [Microtron Centre, Department of Studies in Physics, Mangalore University, Mangalagangotri 574199, Karnataka (India); Okram, G.S. [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452017 (India)

    2016-01-01

    Highlights: • Pristine and irradiated samples follow small polaron hopping model in high temperature range. • Reduction in volume is seen via electron beam irradiation. • High temperature thermoelectric power data follows small polaron hopping model. • Electron beam irradiation enhances thermoelectric power for Gd{sub 0.5}Sr{sub 0.5}MnO{sub 3} compounds. - Abstract: We present systematic studies on the effect of electron beam irradiation on structural, electrical and thermal properties of Gd{sub 0.5}Sr{sub 0.5}MnO{sub 3} and Dy{sub 0.5}Sr{sub 0.5}MnO{sub 3} manganites. The XRD patterns and Rietveld analysis show that the samples remain single phased even after they undergo electron beam irradiation. Both the series of the samples Gd{sub 0.5}Sr{sub 0.5}MnO{sub 3} and Dy{sub 0.5}Sr{sub 0.5}MnO{sub 3} show insulating trends in their temperature dependent electrical resistivity, ρ(T) behavior. The resistivity data for both the series of samples (pristine as well as irradiated) indicate that the small polaron hopping model is valid in high temperature region; on contrary, variable range hopping model governs the low temperature regime. Magnetic studies demonstrate that the Neel temperatures of pristine and irradiated samples of Gd{sub 0.5}Sr{sub 0.5}MnO{sub 3} and Dy{sub 0.5}Sr{sub 0.5}MnO{sub 3} do not change appreciably when they are subjected to irradiation. Thermo-electrical power is observed to increase with irradiation in Gd{sub 0.5}Sr{sub 0.5}MnO{sub 3} samples, whereas for Dy{sub 0.5}Sr{sub 0.5}MnO{sub 3} samples a decrease in thermo-electric power is seen when the samples are irradiated.

  19. Supersonic Fe beam source for chromatic aberration-free laser focusing of atoms

    CERN Document Server

    Bosch, R C M; Van der Straten, P; Leeuwen, K A H

    2002-01-01

    A monochromatic Fe beam is generated by heated supersonic expansion of argon seeded with Fe vapor. At a nozzle temperature of 1930 K and 800 torr argon inlet pressure the Fe beam has an axial velocity spread of 8% and intensity of 3 x 10 sup 1 sup 5 s sup - sup 1 sr sup - sup 1 , corresponding to a deposition rate of 10 nm/h at 150 mm from the nozzle. The two-chamber alumina crucibles are chemically stable for liquid Fe. With 400 mm sup 3 Fe we have operated for more than 200 hours without reloading. The power consumption at 1930 K is 750 W. Temperature stability at constant power (without feedback) is better than 30 K. The source is intended for deposition of nano-structures by laser focusing of the Fe beam. The small axial velocity spread virtually eliminates the increase in focal spot size due to chromatic aberration. (authors)

  20. Monochromatic computed tomography with a compact laser-driven X-ray source.

    Science.gov (United States)

    Achterhold, K; Bech, M; Schleede, S; Potdevin, G; Ruth, R; Loewen, R; Pfeiffer, F

    2013-01-01

    A laser-driven electron-storage ring can produce nearly monochromatic, tunable X-rays in the keV energy regime by inverse Compton scattering. The small footprint, relative low cost and excellent beam quality provide the prospect for valuable preclinical use in radiography and tomography. The monochromaticity of the beam prevents beam hardening effects that are a serious problem in quantitative determination of absorption coefficients. These values are important e.g. for osteoporosis risk assessment. Here, we report quantitative computed tomography (CT) measurements using a laser-driven compact electron-storage ring X-ray source. The experimental results obtained for quantitative CT measurements on mass absorption coefficients in a phantom sample are compared to results from a rotating anode X-ray tube generator at various peak voltages. The findings confirm that a laser-driven electron-storage ring X-ray source can indeed yield much higher CT image quality, particularly if quantitative aspects of computed tomographic imaging are considered.

  1. Study on paper moisture measurement method by monochromatic light sources

    Science.gov (United States)

    Mo, Changtao; Du, Xin; He, Ping; Zhang, Lili; Li, Nan; Wang, Ming

    2010-10-01

    We design the emission and detection optical paths of three monochromatic infrared light sources with different wavelength. The three light sources are placed according to the different angles, so that the three kinds of monochromatic lights are converged on the same point of the sample. Using the method, we can detect the same point and improve the measurement accuracy. We choose the standard near-infrared monochromatic light source, so that we can save some equipments, such as tungsten- halogen lamp, filtered wheel, collimation focalizer, electric machine, and so on. In particular, we save the cumbersome cooling system, reduce the volume of the instrument greatly and reduce the cost. The three monochromatic light sources are supplied by the same pulse power source, to ensure their synchronous working.

  2. Relief Restoration of Complicated form Objects by Monochromatic Microwave Radiation

    Directory of Open Access Journals (Sweden)

    Kuzmenko Ivan

    2016-01-01

    Full Text Available Article demonstrates possibility of monochromatic radiation usage for relief restoration. There is a problem with restoration when scanned object is not flat and it is not parallel to the scanning plane. It was discovered that two-dimensional phase distribution could be applied for distance determination. It is reliable way to solve problems listed above. In conclusion offered methods allow monochromatic microwave radiation usage for screening system development.

  3. Dual energy CT: How well can pseudo-monochromatic imaging reduce metal artifacts?

    Energy Technology Data Exchange (ETDEWEB)

    Kuchenbecker, Stefan, E-mail: stefan.kuchenbecker@dkfz.de; Faby, Sebastian; Sawall, Stefan; Kachelrieß, Marc [German Cancer Research Center (DKFZ), Heidelberg 69120 (Germany); Lell, Michael [Friedrich-Alexander-University (FAU), Erlangen 91054 (Germany)

    2015-02-15

    implant. For each case, the contrast-to-noise ratio (CNR) was assessed. Results: In the simulation, the pseudo-monochromatic images yielded acceptable artifact reduction results. However, the CNR in the artifact-reduced images was more than 60% lower than in the original polychromatic images. In contrast, the raw data-based material decomposition did not significantly reduce the CNR in the virtual monochromatic images. Regarding the patient data with beam hardening artifacts and with metal artifacts from small implants the pseudo-monochromatic method was able to reduce the artifacts, again with the downside of a significant CNR reduction. More intense metal artifacts, e.g., as those caused by an artificial hip joint, could not be suppressed. Conclusions: Pseudo-monochromatic imaging is able to reduce beam hardening, scatter, and metal artifacts in some cases but it cannot remove them. In all cases, the CNR is significantly reduced, thereby rendering the method questionable, unless special post processing algorithms are implemented to restore the high CNR from the original images (e.g., by using a frequency split technique). Raw data-based dual energy decomposition methods should be preferred, in particular, because the CNR penalty is almost negligible.

  4. Use of XR-QA2 radiochromic films for quantitative imaging of a synchrotron radiation beam

    Science.gov (United States)

    Di Lillo, F.; Dreossi, D.; Emiro, F.; Fedon, C.; Longo, R.; Mettivier, G.; Rigon, L.; Russo, P.; Tromba, G.

    2015-05-01

    In the framework of an ongoing project, promoted by INFN, at the SYRMEP beamline of the ELETTRA synchrotron radiation facility (Trieste, Italy) for phase-contrast breast X-ray computed tomography, the assessment of the dose to the breast is one of the issues, requiring the determination of the distribution of X-ray incident photon fluence. This work investigates the use of XR-QA2 radiochromic films for quantitative imaging of the synchrotron radiation (SR) beam. XR-QA2 films were irradiated in a plane transverse to the beam axis, with a monochromatic beam of energy of 28, 35, 38 or 40 keV. The response of the radiochromic film was calibrated in terms of average air kerma measured with an ionization chamber. The net reflectance of the exposed film was then converted to photon fluence per unit air kerma (mm-2mGy-1). The SR beam profile was acquired also with a scintillator (GOS) based, fiber optic coupled CCD camera as well as with a scintillator based flat panel detector. Horizontal and vertical line profiles acquired with the radiochromic films show the 2D distribution of the beam intensity, with variations in the order of 15-20% in the horizontal direction. The response of the radiochromic film is comparable to that of the other imaging detectors, within less than 5% variation.

  5. Non-destructive characterization of minerals in ancient Greek ceramics using monochromatic neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Siouris, I M [Department of Production and Management Engineering, Democritus University of Thrace Xanthi, 67100 Xanthis (Greece); Department of Informatics and Communication, Technological and Educational, Institute of Serres, SimLab, 62124 Serres (Greece)], E-mail: jsiou@pme.duth.gr

    2008-03-12

    A collection of ancient Greek ceramic pieces originating from different excavations from Neos Scopos, Serres, in the North East of Greece has been studied at room temperature by means of non-destructive neutron diffraction using a monochromatic beam. Quantitative phase analyses revealed different compositions of the mineral fractions present, but a general similarity of the main materials is still recognizable. It is shown that the observed variations are partly due to the experimental set-up and they can be remedied by taking a sufficient number of measurements for different sample orientations while bathing the entire object in the beam. An additional reason for the observed anomaly in the mineral phase compositions may be the different heat treatments to which the mixtures of clays/pastes was subjected as well as the postproduction environmental conditions for the selected samples. The firing temperatures were estimated to be in the range of 850-1000 deg. C.

  6. SU-E-I-40: Phantom Research On Monochromatic Images Taken by Dual CBCT with Multiple Energy Sets

    Energy Technology Data Exchange (ETDEWEB)

    Gao, R [Duke University, Durham, NC - North Carolina (United States); Shandong University, Jinan, Shandong (China); Wang, H [Shandong University, Jinan, Shandong (China); Zhang, Y [Duke University, Durham, NC - North Carolina (United States); Mao, R [The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan (China); Ren, L; Yin, F [Duke University Medical Center, Durham, NC (United States)

    2015-06-15

    Purpose: To evaluate the quality of monochromatic images at the same virtual monochromatic energy using dual cone-beam computed tomography (CBCT) with either kV/kV or MV/kV or MV/MV energy sets. Methods: CT images of Catphan 504 phantom were acquired using four different KV and MV settings: 80kV, 140kV, 4MV, 6MV. Three sets of monochromatic images were calculated: 80kV-140kV, 140kV-4MV and 4MV-6MV. Each set of CBCT images were reconstructed from the same selected virtual monochromatic energy of 1MeV. Contrast-to-Noise Ratios (CNRs) were calculated and compared between each pair of images with different energy sets. Results: Between kV/MV and MV/MV images, the CNRs are comparable for all inserts. However, differences of CNRs were observed between the kV/kV and kV/MV images. Delrin’s CNR ratio between kV/kV image and kV/MV image is 1.634. LDPE’s (Low-Density Polyethylene) CNR ratio between kV/kV and kV/MV images is 0.509. Polystyrene’s CNR ratio between kV/kV image and kV/MV image is 2.219. Conclusion: Preliminary results indicated that the CNRs calculated from CBCT images reconstructed from either kV/MV projections or MV/MV projections for the same selected virtual monochromatic energy may be comparable.

  7. Broadband, monochromatic and quasi-monochromatic x-ray propagation in multi-Z media for imaging and diagnostics

    Science.gov (United States)

    Westphal, Maximillian S.; Lim, Sara N.; Nahar, Sultana N.; Chowdhury, Enam; Pradhan, Anil K.

    2017-08-01

    With the advent of monochromatic and quasi-monochromatic x-ray sources, we explore their potential with computational and experimental studies on propagation through a combination of low and high-Z (atomic number) media for applications to imaging and detection. The multi-purpose code GEANT4 and a new code PHOTX are employed in numerical simulations, and a variety of x-ray sources are considered: conventional broadband devices with well-known spectra, quasi-monochromatic laser driven sources, and monochromatic synchrotron x-rays. Phantom samples consisting of layers of low-Z and high-Z material are utilized, with atomic-molecular species ranging from H2O to gold. Differential and total attenuation of x-ray fluxes from the different x-ray sources are illustrated through simulated x-ray images. Main conclusions of this study are: I. It is shown that a 65 keV Gaussian quasi-monochromatic source is capable of better contrast with less radiation exposure than a common 120 kV broadband simulator. II. A quantitative measure is defined and computed as a metric to compare the efficacy of any two x-ray sources, as a function of concentration of high-Z moieties in predominantly low-Z environment and depth of penetration. III. Characteristic spectral features of \

  8. Time-reversing a monochromatic subwavelength optical focus by optical phase conjugation of multiply-scattered light

    CERN Document Server

    Park, Jongchan; Lee, KyeoReh; Cho, Yong-Hoon; Park, YongKeun

    2016-01-01

    Due to its time-reversal nature, optical phase conjugation generates a monochromatic light wave which retraces its propagation paths. Here, we demonstrate the regeneration of a subwavelength optical focus by phase conjugation. Monochromatic light from a subwavelength source is scattered by random nanoparticles, and the scattered light is phase conjugated at the far-field region by coupling its wavefront into a single-mode optical reflector using a spatial light modulator. Then the conjugated beam retraces its propagation paths and forms a refocus on the source at the subwavelength scale. This is the first direct experimental realization of subwavelength focusing beyond the diffraction limit with far-field time reversal in the optical domain.

  9. Reconstruction of quasi-monochromatic images from a multiple monochromatic x-ray imaging diagnostic for inertial confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, N; Turner, R; Barbee, T; Koch, J; Welser, L; Mansini, R

    2004-04-15

    We have developed a software package for image reconstruction of a multiple monochromatic x-ray imaging diagnostics (MMI) for diagnostic of inertial conferment fusion capsules. The MMI consists of a pinhole array, a multi-layer Bragg mirror, and a charge injection device image detector (CID). The pinhole array projects {approx}500 sub-images onto the CID after reflection off the multi-layer Bragg mirror. The obtained raw images have continuum spectral dispersion on its vertical axis. For systematic analysis, a computer-aided reconstruction of the quasi-monochromatic image is essential.

  10. Geant4 simulation of the PSI LEM beam line: energy loss and muonium formation in thin foils and the impact of unmoderated muons on the $\\mu$SR spectrometer

    CERN Document Server

    Khaw, Kim Siang; Crivelli, Paolo; Kirch, Klaus; Morenzoni, Elvezio; Salman, Zaher; Suter, Andreas; Prokscha, Thomas

    2015-01-01

    The PSI low-energy $\\mu$SR spectrometer is an instrument dedicated to muon spin rotation and relaxation measurements. Knowledge of the muon beam parameters such as spatial, kinetic energy and arrival-time distributions at the sample position are important ingredients to analyze the $\\mu$SR spectra. We present here the measured energy losses in the thin carbon foil of the muon start detector deduced from time-of-flight measurements. Muonium formation in the thin carbon foil (10 nm thickness) of the muon start detector also affect the measurable decay asymmetry and therefore need to be accounted for. Muonium formation and energy losses in the start detector, whose relevance increase with decreasing muon implantation energy ($<10$ keV), have been implemented in Geant4 Monte Carlo simulation to reproduce the measured time-of-flight spectra. Simulated and measured time-of-flight and beam spot agrees only if a small fraction of so called "unmoderated" muons which contaminate the mono-energetic muon beam of the $...

  11. On monochromatic arm exponents for 2D critical percolation

    CERN Document Server

    Beffara, Vincent

    2009-01-01

    We investigate the so-called monochromatic arm exponents for critical percolation in two dimensions. These exponents, describing the probability of observing j disjoint macroscopic paths, are shown to exist and to form a different family from the (now well-understood) polychromatic exponents.

  12. Kernels by Monochromatic Paths and Color-Perfect Digraphs

    Directory of Open Access Journals (Sweden)

    Galeana-Śanchez Hortensia

    2016-05-01

    Full Text Available For a digraph D, V (D and A(D will denote the sets of vertices and arcs of D respectively. In an arc-colored digraph, a subset K of V(D is said to be kernel by monochromatic paths (mp-kernel if (1 for any two different vertices x, y in N there is no monochromatic directed path between them (N is mp-independent and (2 for each vertex u in V (D \\ N there exists v ∈ N such that there is a monochromatic directed path from u to v in D (N is mp-absorbent. If every arc in D has a different color, then a kernel by monochromatic paths is said to be a kernel. Two associated digraphs to an arc-colored digraph are the closure and the color-class digraph CC(D. In this paper we will approach an mp-kernel via the closure of induced subdigraphs of D which have the property of having few colors in their arcs with respect to D. We will introduce the concept of color-perfect digraph and we are going to prove that if D is an arc-colored digraph such that D is a quasi color-perfect digraph and CC(D is not strong, then D has an mp-kernel. Previous interesting results are generalized, as for example Richardson′s Theorem.

  13. Classical stabilization of the hydrogen atom in a monochromatic field

    Energy Technology Data Exchange (ETDEWEB)

    Benvenuto, F.; Casati, G. (Dipartimento di Fisica dell' Universita, Via Castelnuovo 7, 22100 Como (Italy)); Shepelyansky, D.L. (Laboratoire de Physique Quantique, Universite Paul Sabatier, 31062, Toulouse (France))

    1993-02-01

    We report the results of analytical and numerical investigations on the ionization of a classical atom in a strong, linearly polarized, monochromatic field. We show that the ionization probability decreases with increasing field intensity at field amplitudes much larger than the classical chaos border. This effect should be observable in real laboratory experiments.

  14. Constraining the monochromatic gamma-rays from dark matter annihilation by the LHC

    Science.gov (United States)

    Esmaili, Arman; Khatibi, Sara; Mohammadi Najafabadi, Mojtaba

    2017-07-01

    The installation of forward detectors in CMS and ATLAS turn the LHC into an effective photon-photon collider. The elastic scattering of the beam protons via the emission of photons, which can be identified by tagging the intact protons in the forward detectors, provides a powerful diagnostic of the central production of new particles through photon-photon annihilation. In this paper we study the central production of dark matter particles and the potential of the LHC to constrain the cross section of this process. By virtue of the crossing symmetry, this limit can immediately be used to constrain the production of monochromatic gamma rays in dark matter annihilation, a smoking gun signal under investigation in indirect dark matter searches. We show that with the integrated luminosity L =30 fb-1 in the LHC at center-of-mass energy √{s }=13 TeV , for dark matter masses ˜(50 - 600 ) GeV , a model-independent constraint on the cross section of dark matter annihilation to monochromatic gamma rays at the same order of magnitude as the current Fermi-LAT and the future limits from CTA can be obtained.

  15. Constraining the monochromatic gamma-rays from dark matter annihilation by the LHC

    CERN Document Server

    Esmaili, Arman; Najafabadi, Mojtaba Mohammadi

    2016-01-01

    The installation of forward detectors in CMS and ATLAS turn the LHC to an effective photon-photon collider. The elastic scattering of the beam-protons via the emission of photons, which can be identified by tagging the intact protons in the forward detectors, provides a powerful diagnostic of the central production of new particles through photon-photon annihilation. In this letter we study the central production of dark matter particles and the potential of LHC to constrain the cross section of this process. By virtue of the crossing symmetry, this limit can immediately be used to constrain the production of monochromatic gamma-rays in dark matter annihilation, a smoking gun signal under investigation in indirect dark matter searches. We show that with the integrated luminosity $\\mathcal{L}=30~{\\rm fb}^{-1}$ in LHC at center-of-mass energy $\\sqrt{s}=$ 13 TeV, for dark matter masses $\\sim (50-600)$ GeV, a model-independent constraint on the cross section of dark matter annihilation to monochromatic gamma-rays...

  16. Detection limits for actinides in a monochromatic, wavelength-dispersive x-ray fluorescence instrument

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Michael L [Los Alamos National Laboratory; Havrilla, George J [Los Alamos National Laboratory

    2009-01-01

    Recent developments in x-ray optics have made it possible to examine the L x-rays of actinides using doubly-curved crystals in a bench-top device. A doubly-curved crystal (DCC) acts as a focusing monochromatic filter for polychromatic x-rays. A Monochromatic, Wavelength-Dispersive X-Ray Fluorescence (MWDXRF) instrument that uses DCCs to measure Cm and Pu in reprocessing plant liquors was proposed in 2007 by the authors at Los Alamos National Laboratory. A prototype design of this MWDXRF instrument was developed in collaboration with X-ray Optical Systems Inc. (XOS), of East Greenbush, New York. In the MWDXRF instrument, x-rays from a Rhodium-anode x-ray tube are passed through a primary DCC to produce a monochromatic beam of 20.2-keV photons. This beam is focused on a specimen that may contain actinides. The 20.2-keV interrogating beam is just above the L3 edge of Californium; each actinide (with Z = 90 to 98) present in the specimen emits characteristic L x-rays as the result of L3-shell vacancies. In the LANL-XOS prototype MWDXRf, these x-rays enter a secondary DCC optic that preferentially passes 14.961-keV photons, corresponding to the L-alpha-1 x-ray peak of Curium. In the present stage of experimentation, Curium-bearing specimens have not been analyzed with the prototype MWDXRF instrument. Surrogate materials for Curium include Rubidium, which has a K-beta-l x-ray at 14.961 keV, and Yttrium, which has a K-alpha-1 x-ray at 14.958 keV. In this paper, the lower limit of detection for Curium in the LANL-XOS prototype MWDXRF instrument is estimated. The basis for this estimate is described, including a description of computational models and benchmarking techniques used. Detection limits for other actinides are considered, as well as future safeguards applications for MWDXRF instrumentation.

  17. Statistical analysis of monochromatic whistler waves near the Moon detected by Kaguya

    Directory of Open Access Journals (Sweden)

    Y. Katoh

    2011-05-01

    Full Text Available Observations are presented of monochromatic whistler waves near the Moon detected by the Lunar Magnetometer (LMAG on board Kaguya. The waves were observed as narrowband magnetic fluctuations with frequencies close to 1 Hz, and were mostly left-hand polarized in the spacecraft frame. We performed a statistical analysis of the waves to identify the distributions of their intensity and occurrence. The results indicate that the waves were generated by the solar wind interaction with lunar crustal magnetic anomalies. The conditions for observation of the waves strongly depend on the solar zenith angle (SZA, and a high occurrence rate is recognized in the region of SZA between 40° to 90° with remarkable north-south and dawn-dusk asymmetries. We suggest that ion beams reflected by the lunar magnetic anomalies are a possible source of the waves.

  18. Definition and measurement of the beam propagation factor M2 for chromatic laser beams

    Institute of Scientific and Technical Information of China (English)

    Tao Fang; Xin Ye; Jinfu Niu; Jianqiu Xu

    2006-01-01

    The concept of the beam propagation factor M2 is extended for chromatic laser beams. The definition of the beam propagation factor can be generalized with the weighted effective wavelength. Using the new definition of factor M2, the propagation of chromatic beams can be analyzed by the beam propagation factor M2 as same as that of monochromatic beams. A simple method to measure the chromatic beam factor M2 is demonstrated. The chromatic factor M2 is found invariable while the laser beam propagates through the dispersion-free ABCD system.

  19. The new versatile general purpose surface-muon instrument (GPS) based on silicon photomultipliers for μSR measurements on a continuous-wave beam

    Science.gov (United States)

    Amato, A.; Luetkens, H.; Sedlak, K.; Stoykov, A.; Scheuermann, R.; Elender, M.; Raselli, A.; Graf, D.

    2017-09-01

    We report on the design and commissioning of a new spectrometer for muon-spin relaxation/rotation studies installed at the Swiss Muon Source (SμS) of the Paul Scherrer Institute (PSI, Switzerland). This new instrument is essentially a new design and replaces the old general-purpose surface-muon (GPS) instrument that has been for long the workhorse of the μSR user facility at PSI. By making use of muon and positron detectors made of plastic scintillators read out by silicon photomultipliers, a time resolution of the complete instrument of about 160 ps (standard deviation) could be achieved. In addition, the absence of light guides, which are needed in traditionally built μSR instrument to deliver the scintillation light to photomultiplier tubes located outside magnetic fields applied, allowed us to design a compact instrument with a detector set covering an increased solid angle compared with the old GPS.

  20. Tunable, all-optical quasi-monochromatic Thomson X-ray source

    CERN Document Server

    Khrennikov, K; Buck, A; Xu, J; Heigoldt, M; Veisz, L; Karsch, S

    2014-01-01

    Brilliant X-ray sources are of great interest for many research fields from biology via medicine to material research. The quest for a cost-effective, brilliant source with unprecedented temporal resolution has led to the recent realization of various high-intensity-laser-driven X-ray beam sources. Here we demonstrate the first all-laser-driven, energy-tunable and quasi-monochromatic X-ray source based on Thomson backscattering. This is a decisive step beyond previous results, where the emitted radiation exhibited an uncontrolled broad energy distribution. In the experiment, one part of the laser beam was used to drive a few-fs bunch of quasi-monoenergetic electrons from a Laser-Wakefield Accelerator (LWFA), while the remainder was scattered off the bunch in a near-counter-propagating geometry. When the electron energy was tuned from 10-50 MeV, narrow-bandwidth X-ray spectra peaking at 5-35keV were directly measured, limited in photon energy by the sensitivity curve of our X-ray detector. Due to the ultrashor...

  1. Trace chemical characterization using monochromatic X-ray undulator radiation

    Science.gov (United States)

    Eba; Numako; Iihara; Sakurai

    2000-06-01

    An efficient Johansson-type X-ray fluorescence spectrometer has been developed for advanced X-ray spectroscopic analysis with third-generation synchrotron radiation. Kalpha and Kbeta X-ray fluorescence spectra for trace metals have been collected by a Ge(220) analyzing crystal with a Rowland radius of 150 mm, under monochromatic X-ray excitation at the undulator beamline at the SPring-8. The energy resolution is approximately 10 eV for most of the K lines for 3d transition metals. In light of the greatly improved efficiency, as well as the excellent signal-to-background ratio, the relative and absolute detection limits achieved are 1 ppm and 1.2 ng of copper in a carbon matrix, respectively. The energy resolution of the present spectrometer permits the observation of some chemical effects in Kbeta spectra. It has been demonstrated that the changes in Kbeta5 and Kbeta'' intensity for iron and cobalt compounds can be used for the analysis of chemical states. Resonant X-ray fluorescent spectra are another important application of monochromatic excitation. In view of trace chemical characterization, the present spectrometer can be a good alternative to a conventional Si(Li) detector system when combined with highly brilliant X-rays.

  2. Effect of Electron Beam on the Structure and Crystallization Features of BaO-SrO-TiO2-SiO2 Glass

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Glasses of BaO-SrO-TiO2-SiO2 after electronic radiation treatment of 50-1000 kgy were studied by means of IR spectra, DTA and visible light absorption method.The result shows that the glass structure is changed due to the formation of structure defect from oxygen vacancy and E′ color center,which resultsd in the crystallization process and new precursors,and decreasement of Tg temperature and crystallization peaks by 20-50℃.

  3. Shape coexistence in neutron-rich Sr isotopes : Coulomb excitation of 98Sr

    NARCIS (Netherlands)

    Clément, E; Görgen, A.; Korten, W.; Walle J. van de, [No Value

    2010-01-01

    In this addendum we ask for beam time to perform Coulomb excitation of 98Sr in order to complete our program on the study of shape coexistence and evolution of collectivity in neutron rich strontium isotopes at N=60.

  4. Preliminary experimental study and simulation of an energy-tunable quasi-monochromatic laser-Compton X/γ-ray source

    Institute of Scientific and Technical Information of China (English)

    LUO We; XU Wang; ZHUO Hong-Bin; MA Yan-Yun

    2012-01-01

    We propose a slanting collision scheme for Compton scattering of a laser light against a relativistic electron beam.This scheme is suitable to generate an energy-tunable X/γ-ray source.In this paper,we present theoretical study and simulation of the spectral,spatial and temporal characteristics of such a source.We also describe two terms laser-Compton scattering (LCS) experiments at the 100 MeV Linac of Shanghai Institute of Applied Physics,where quasi-monochromatic LCS X-ray energy spectra with peak energies of ~30 keV are observed successfully.These preliminary investigations are carried out to understand the feasibility of developing an energy-tunable quasi-monochromatic X/γ-ray source,the future Shanghai Laser Electron Gamma Source.

  5. Progress report on neutron beam experiments in Thailand: effects of antimony substitutions on the critical temperature of Bi-Pb-Sr-Ca-Cu-O compounds

    Energy Technology Data Exchange (ETDEWEB)

    Sangariyavanich, A.; Ampornrat, P. [Office of Atomic Energy for Peace, Bangkok (Thailand)

    1998-10-01

    Effects of systematic substitutions of antimony for bismuth in Bi{sub 1.8-x}Pb{sub 0.2}Sb{sub x}Sr{sub 2}Ca{sub 3}Cu{sub 4}O{sub 10} have been investigated. Fabrication of the specimens has been performed by solid state reaction in air. The samples were sintered between 820degC - 843degC for 65 hours and subsequently quenched in liquid nitrogen. The critical temperatures of most specimens as determined by standard four-probe technique was higher than 100 K. Phase identification by X-ray diffraction technique indicated that `2223` and `2234` were the predominant phases in these samples. (author)

  6. Molecular beam epitaxy growth and post-growth annealing of FeSe films on SrTiO3: a scanning tunneling microscopy study.

    Science.gov (United States)

    Li, Zhi; Peng, Jun-Ping; Zhang, Hui-Min; Zhang, Wen-Hao; Ding, Hao; Deng, Peng; Chang, Kai; Song, Can-Li; Ji, Shuai-Hua; Wang, Lili; He, Ke; Chen, Xi; Xue, Qi-Kun; Ma, Xu-Cun

    2014-07-02

    Low temperature scanning tunneling microscopy and spectroscopy are used to investigate the atomic and electronic structure evolution of FeSe films grown on SrTiO3 as a function of post-growth annealing. Single unit cell FeSe films are found to bond strongly with the underlying substrate, and become superconductive with diminishing chemical bond disorders at the interface via post-annealing. For thicker FeSe films, post-annealing removes excess Se in the films and leads to a transition from semiconductor into metallic behaviors. In double and multilayer films, strain-induced complex textures are observed and suggested to be the main cause for the absent superconductivity.

  7. On the detectability of Galactic dark matter annihilation into monochromatic gamma-rays

    Institute of Scientific and Technical Information of China (English)

    唐志成; 袁强; 毕效军; 陈国明

    2011-01-01

    Monochromatic y-rays are thought to be the smoking gun signal for identifying dark matter annihilation. However, the flux of monochromatic y-rays is usually suppressed by virtual quantum effects since dark matter should be neutral and does not couple with

  8. Perspective of monochromatic gamma-ray line detection with the High Energy cosmic-Radiation Detection (HERD) facility onboard China's Space Station

    CERN Document Server

    Huang, Xiaoyuan; Tsai, Yue-Lin Sming; Xu, Ming; Yuan, Qiang; Chang, Jin; Dong, Yong-Wei; Hu, Bing-Liang; Lü, Jun-Guang; Wang, Le; Wu, Bo-Bing; Zhang, Shuang-Nan

    2015-01-01

    HERD is the High Energy cosmic-Radiation Detection instrument proposed to operate onboard China's space station in the 2020s. It is designed to detect energetic cosmic ray nuclei, leptons and photons with a high energy resolution ($\\sim1\\%$ for electrons and photons and $20\\%$ for nuclei) and a large geometry factor ($>3\\, m^2sr$ for electrons and diffuse photons and $>2\\, m^2sr$ for nuclei). In this work we discuss the capability of HERD to detect monochromatic $\\gamma$-ray lines, based on simulations of the detector performance. It is shown that HERD will be one of the most sensitive instruments for monochromatic $\\gamma$-ray searches at energies between $\\sim10$ to a few hundred GeV. Above hundreds of GeV, Cherenkov telescopes will be more sensitive due to their large effective area. As a specific example, we show that a good portion of the parameter space of a supersymmetric dark matter model can be probed with HERD.

  9. Perspective of monochromatic gamma-ray line detection with the High Energy cosmic-Radiation Detection (HERD) facility onboard China's space station

    Science.gov (United States)

    Huang, Xiaoyuan; Lamperstorfer, Anna S.; Tsai, Yue-Lin Sming; Xu, Ming; Yuan, Qiang; Chang, Jin; Dong, Yong-Wei; Hu, Bing-Liang; Lü, Jun-Guang; Wang, Le; Wu, Bo-Bing; Zhang, Shuang-Nan

    2016-05-01

    HERD is the High Energy cosmic-Radiation Detection instrument proposed to operate onboard China's space station in the 2020s. It is designed to detect energetic cosmic ray nuclei, leptons and photons with a high energy resolution (∼1% for electrons and photons and 20% for nuclei) and a large geometry factor (>3 m2 sr for electrons and diffuse photons and > [2]m2 sr for nuclei). In this work we discuss the capability of HERD to detect monochromatic γ-ray lines, based on simulations of the detector performance. It is shown that HERD will be one of the most sensitive instruments for monochromatic γ-ray searches at energies between ∼ 10 to a few hundred GeV. Above hundreds of GeV, Cherenkov telescopes will be more sensitive due to their large effective area. As a specific example, we show that a good portion of the parameter space of a supersymmetric dark matter model can be probed with HERD.

  10. On the detectability of Galactic dark matter annihilation into monochromatic gamma-rays

    Institute of Scientific and Technical Information of China (English)

    TANG Zhi-Cheng; YUAN Qiang; BI Xiao-Jun; CHEN Guo-Ming

    2011-01-01

    Monochromatic γ-rays are thought to be the smoking gun signal for identifying dark matter annihilation. However, the flux of monochromatic γ-rays is usually suppressed by virtual quantum effects since dark matter should be neutral and does not couple with γ-rays directly. In this work, we study the detection strategy of the monochromatic γ-rays in a future space-based detector. The flux of monochromatic γ-rays between 50 GeV and several TeV is calculated by assuming the supersymmetric neutralino as a typical dark matter candidate. The detection both by focusing on the Galactic center and in a scan mode that detects γ-rays from the whole Galactic halo are compared. The detector performance for the purpose of monochromatic γ-ray detection, with different energy and angular resolution, field of view, and background rejection efficiencies, is carefully studied with both analytical and fast Monte-Carlo methods.

  11. On the Detectability of Galactic Dark Matter Annihilation into Monochromatic Gamma-rays

    CERN Document Server

    Tang, Zhi-Cheng; Bi, Xiao-Jun; Chen, Guo-Ming

    2010-01-01

    Monochromatic gamma-rays are thought to be the smoking gun signal for identifying the dark matter annihilation. However, the flux of monochromatic gamma-rays is usually suppressed by the virtual quantum effects since dark matter should be neutral and does not couple with gamma-rays directly. In the work we study the detection strategy of the monochromatic gamma-rays in a future space-based detector. The monochromatic gamma-ray flux is calculated by assuming supersymmetric neutralino as a typical dark matter candidate. We discuss both the detection focusing on the Galactic center and in a scan mode which detects gamma-rays from the whole Galactic halo are compared. The detector performance for the purpose of monochromatic gamma-rays detection, with different energy and angular resolution, field of view, background rejection efficiencies, is carefully studied with both analytical and fast Monte-Carlo method.

  12. Fusion of colour and monochromatic images with edge emphasis

    Directory of Open Access Journals (Sweden)

    Rade M. Pavlović

    2014-02-01

    Full Text Available We propose a novel method to fuse true colour images with monochromatic non-visible range images that seeks to encode important structural information from monochromatic images efficiently but also preserve the natural appearance of the available true chromacity information. We utilise the β colour opponency channel of the lαβ colour as the domain to fuse information from the monochromatic input into the colour input by the way of robust grayscale fusion. This is followed by an effective gradient structure visualisation step that enhances the visibility of monochromatic information in the final colour fused image. Images fused using this method preserve their natural appearance and chromacity better than conventional methods while at the same time clearly encode structural information from the monochormatic input. This is demonstrated on a number of well-known true colour fusion examples and confirmed by the results of subjective trials on the data from several colour fusion scenarios. Introduction The goal of image fusion can be broadly defined as: the representation of visual information contained in a number of input images into a single fused image without distortion or loss of information. In practice, however, a representation of all available information from multiple inputs in a single image is almost impossible and fusion is generally a data reduction task.  One of the sensors usually provides a true colour image that by definition has all of its data dimensions already populated by the spatial and chromatic information. Fusing such images with information from monochromatic inputs in a conventional manner can severely affect natural appearance of the fused image. This is a difficult problem and partly the reason why colour fusion received only a fraction of the attention than better behaved grayscale fusion even long after colour sensors became widespread. Fusion method Humans tend to see colours as contrasts between opponent

  13. Sex and vision II: color appearance of monochromatic lights

    Directory of Open Access Journals (Sweden)

    Abramov Israel

    2012-09-01

    Full Text Available Abstract Background Because cerebral cortex has a very large number of testosterone receptors, we examined the possible sex differences in color appearance of monochromatic lights across the visible spectrum. There is a history of men and women perceiving color differently. However, all of these studies deal with higher cognitive functions which may be culture-biased. We study basic visual functions, such as color appearance, without reference to any objects. We present here a detailed analysis of sex differences in primary chromatic sensations. Methods We tested large groups of young adults with normal vision, including spatial and temporal resolution, and stereopsis. Based on standard color-screening and anomaloscope data, we excluded all color-deficient observers. Stimuli were equi-luminant monochromatic lights across the spectrum. They were foveally-viewed flashes presented against a dark background. The elicited sensations were measured using magnitude estimation of hue and saturation. When the only permitted hue terms are red (R yellow (Y, green (G, blue (B, alone or in combination, such hue descriptions are language-independent and the hue and saturation values can be used to derive a wide range of color-discrimination functions. Results There were relatively small but clear and significant, differences between males and females in the hue sensations elicited by almost the entire spectrum. Generally, males required a slightly longer wavelength to experience the same hue as did females. The spectral loci of the unique hues are not correlated with anomaloscope matches; these matches are directly determined by the spectral sensitivities of L- and M-cones (genes for these cones are on the X-chromosomes. Nor are there correlations between loci of pairs of unique hues (R, Y, G, B. Wavelength-discrimination functions derived from the scaling data show that males have a broader range of poorer discrimination in the middle of the spectrum. The

  14. SR-71 flyover

    Science.gov (United States)

    1990-01-01

    atmospheric particles at altitudes of 80,000 feet and above where future hypersonic aircraft will be operating. The system used six sheets of laser light projected from the bottom of one of the two 'A' models. As microscopic-sized atmospheric particles passed between the two beams, direction and speed were measured and processed into standard speed and attitude references. An earlier laser air-data collection system was successfully tested at Dryden on an F-l04 testbed. The first of a series of flights using the SR-71 as a science camera platform for the NASA Jet Propulsion Laboratory was flown in March 1993. From the nosebay of the aircraft, an upward-looking ultraviolet video camera studied a variety of celestial objects in wavelengths that are blocked to ground-based astronomers. The SR-71 has also been used in a project for researchers at the University of California-Los Angeles (UCLA) who are investigating the use of charged chlorine atoms to protect and rebuild the ozone layer. The SR-71, operating as a testbed, has been used to assist in the development of a commercial satellite-based instant wireless personal communications network, called the IRIDIUM system, under a NASA commercialization assistance program. In addition, the SR-71 has been used in a program to study ways of reducing sonic boom overpressures that are heard on the ground much like sharp thunderclaps when an aircraft exceeds the speed of sound. Data from this study could eventually lead to aircraft designs that would reduce the 'peak' of sonic booms and minimize the startle affect they produce on the ground. Instruments at precise locations on the ground recorded the sonic booms as the aircraft passed overhead at known altitudes and speeds. An F-16XL aircraft was also used in this study. It was flown behind the SR-71 to 'probe' the near-field shockwave while instrumentation recorded the pressures and other atmospheric parameters. The aircraft has also been used most recently to evaluate a new concept

  15. SR-71 flight

    Science.gov (United States)

    1990-01-01

    atmospheric particles at altitudes of 80,000 feet and above where future hypersonic aircraft will be operating. The system used six sheets of laser light projected from the bottom of one of the two 'A' models. As microscopic-sized atmospheric particles passed between the two beams, direction and speed were measured and processed into standard speed and attitude references. An earlier laser air-data collection system was successfully tested at Dryden on an F-l04 testbed. The first of a series of flights using the SR-71 as a science camera platform for the NASA Jet Propulsion Laboratory was flown in March 1993. From the nosebay of the aircraft, an upward-looking ultraviolet video camera studied a variety of celestial objects in wavelengths that are blocked to ground-based astronomers. The SR-71 has also been used in a project for researchers at the University of California-Los Angeles (UCLA) who are investigating the use of charged chlorine atoms to protect and rebuild the ozone layer. The SR-71, operating as a testbed, has been used to assist in the development of a commercial satellite-based instant wireless personal communications network, called the IRIDIUM system, under a NASA commercialization assistance program. In addition, the SR-71 has been used in a program to study ways of reducing sonic boom overpressures that are heard on the ground much like sharp thunderclaps when an aircraft exceeds the speed of sound. Data from this study could eventually lead to aircraft designs that would reduce the 'peak' of sonic booms and minimize the startle affect they produce on the ground. Instruments at precise locations on the ground recorded the sonic booms as the aircraft passed overhead at known altitudes and speeds. An F-16XL aircraft was also used in this study. It was flown behind the SR-71 to 'probe' the near-field shockwave while instrumentation recorded the pressures and other atmospheric parameters. The aircraft has also been used most recently to evaluate a new concept

  16. Coherence matrix of plasmonic beams

    DEFF Research Database (Denmark)

    Novitsky, Andrey; Lavrinenko, Andrei

    2013-01-01

    We consider monochromatic electromagnetic beams of surface plasmon-polaritons created at interfaces between dielectric media and metals. We theoretically study non-coherent superpositions of elementary surface waves and discuss their spectral degree of polarization, Stokes parameters, and the for...... of the spectral coherence matrix. We compare the polarization properties of the surface plasmonspolaritons as three-dimensional and two-dimensional fields concluding that the latter is superior....

  17. The quasi-monochromatic ULF wave foreshock boundary at Venus

    Science.gov (United States)

    Shan, Lican; Mazelle, Christian; Meziane, Karim; Romanelli, Norberto; Ge, Yasong; Du, Aimin; Lu, Quanming; Zhang, Tielong

    2017-04-01

    The location of ULF quasi-monochromatic wave onsets upstream of Venus bow shock is explored using VEX magnetic field data. We report the existence of a spatial foreshock boundary from which ULF waves are present. It is found that the ULF boundary is sensitive to the interplanetary magnetic field (IMF) direction and appears well defined for a cone-angle larger than 30 degrees. In the Venusian foreshock, the slope of the boundary increases with the cone-angle and for a nominal direction of the IMF, it makes an inclination of 70 degrees with the Sun-Venus direction. Moreover, we have found that the velocity of an ion traveling along the ULF boundary presents a qualitative agreement with the hypothesis of a quasi-adiabatic reflection of a portion of the solar wind at the bow shock. For a nominal IMF direction, the ions associated with the boundary have enough momentum to overcome the solar wind convection. These elements strongly suggest that backstreaming ions upstream of Venus bow shock provide the main energy source of the ULF foreshock waves.

  18. The effect of monochromatic infrared energy on diabetic wound healing.

    Science.gov (United States)

    He, Yayi; Yip, Selina Ly; Cheung, Kwok-Kuen; Huang, Lin; Wang, Shijie; Cheing, Gladys Ly

    2013-12-01

    This study examined the effect of monochromatic infrared energy (MIRE) on diabetic wound healing. Fifteen diabetic rats were given MIRE intervention on their skin wounds located on the dorsum and compared with 15 control diabetic rats. Assessments were conducted for each group at weeks 1, 2 and 4 post wounding (five rats at each time point) by calculating the percentage of wound closures (WCs) and performing histological and immunohistochemical staining on sections of wound tissue. Evaluations of WCs and histological examinations of reepithelialisation, cellular content and granulation tissue formation showed no significant difference between the MIRE and the control group at each time point. Through semi-quantitative immunohistochemical staining, the deposition of type I collagen in the MIRE group was found to have improved when compared with the control group at the end of week 2 (P = 0.05). No significant differences in the myofibroblast population were detected between the two groups. In conclusion, MIRE appeared to promote collagen deposition in the early stage of wound healing in diabetic rats, but the overall wound healing in the MIRE group was not significantly different from that of the control group. © 2012 The Authors. International Wound Journal © 2012 John Wiley & Sons Ltd and Medicalhelplines.com Inc.

  19. How accurate are infrared luminosities from monochromatic photometric extrapolation?

    CERN Document Server

    Lin, Zesen; Kong, Xu

    2016-01-01

    Template-based extrapolations from only one photometric band can be a cost-effective method to estimate the total infrared (IR) luminosities ($L_{\\mathrm{IR}}$) of galaxies. By utilizing multi-wavelength data that covers across 0.35--500\\,$\\mathrm{\\mu m}$ in GOODS-North and GOODS-South fields, we investigate the accuracy of this monochromatic extrapolated $L_{\\mathrm{IR}}$ based on three IR spectral energy distribution (SED) templates (\\citealt[CE01]{Chary2001}; \\citealt[DH02]{Dale2002}; \\citealt[W08]{Wuyts2008a}) out to $z\\sim 3.5$. We find that the CE01 template provides the best estimate of $L_{\\mathrm{IR}}$ in {\\it Herschel}/PACS bands, while the DH02 template performs best in {\\it Herschel}/SPIRE bands. To estimate $L_{\\mathrm{IR}}$, we suggest that extrapolations from the available longest wavelength PACS band based on the CE01 template can be a good estimator. Moreover, if PACS measurement is unavailable, extrapolations from SPIRE observations but based on the \\cite{Dale2002} template can also provide ...

  20. Cell response to quasi-monochromatic light with different coherence

    Science.gov (United States)

    Budagovsky, A. V.; Solovykh, N. V.; Budagovskaya, O. N.; Budagovsky, I. A.

    2015-04-01

    The problem of the light coherence effect on the magnitude of the photoinduced cell response is discussed. The origins of ambiguous interpretation of the known experimental results are considered. Using the biological models, essentially differing in anatomy, morphology and biological functions (acrospires of radish, blackberry microsprouts cultivated in vitro, plum pollen), the effect of statistical properties of quasi-monochromatic light (λmax = 633 nm) on the magnitude of the photoinduced cell response is shown. It is found that for relatively low spatial coherence, the cell functional activity changes insignificantly. The maximal enhancement of growing processes (stimulating effect) is observed when the coherence length Lcoh and the correlation radius rcor are greater than the cell size, i.e., the entire cell fits into the field coherence volume. In this case, the representative indicators (germination of seeds and pollen, the spears length) exceeds those of non-irradiated objects by 1.7 - 3.9 times. For more correct assessment of the effect of light statistical properties on photocontrol processes, it is proposed to replace the qualitative description (coherent - incoherent) with the quantitative one, using the determination of spatial and temporal correlation functions and comparing them with the characteristic dimensions of the biological structures, e.g., the cell size.

  1. Coloring random graphs online without creating monochromatic subgraphs

    CERN Document Server

    Mütze, Torsten; Spöhel, Reto

    2011-01-01

    Consider the following random process: The vertices of a binomial random graph $G_{n,p}$ are revealed one by one, and at each step only the edges induced by the already revealed vertices are visible. Our goal is to assign to each vertex one from a fixed number $r$ of available colors immediately and irrevocably without creating a monochromatic copy of some fixed graph $F$ in the process. Our first main result is that for any $F$ and $r$, the threshold function for this problem is given by $p_0(F,r,n)=n^{-1/m_1^*(F,r)}$, where $m_1^*(F,r)$ denotes the so-called \\emph{online vertex-Ramsey density} of $F$ and $r$. This parameter is defined via a purely deterministic two-player game, in which the random process is replaced by an adversary that is subject to certain restrictions inherited from the random setting. Our second main result states that for any $F$ and $r$, the online vertex-Ramsey density $m_1^*(F,r)$ is a computable rational number. Our lower bound proof is algorithmic, i.e., we obtain polynomial-time...

  2. Cell response to quasi-monochromatic light with different coherence

    Energy Technology Data Exchange (ETDEWEB)

    Budagovsky, A V; Solovykh, N V [I.V.Michurin All-Russian Recearch Institute of Fruit Crops Genetics and Breeding (Russian Federation); Budagovskaya, O N [I.V.Michurin All-Russia Research and Development Institute of Gardening, Michurinsk, Tambov region (Russian Federation); Budagovsky, I A [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2015-04-30

    The problem of the light coherence effect on the magnitude of the photoinduced cell response is discussed. The origins of ambiguous interpretation of the known experimental results are considered. Using the biological models, essentially differing in anatomy, morphology and biological functions (acrospires of radish, blackberry microsprouts cultivated in vitro, plum pollen), the effect of statistical properties of quasi-monochromatic light (λ{sub max} = 633 nm) on the magnitude of the photoinduced cell response is shown. It is found that for relatively low spatial coherence, the cell functional activity changes insignificantly. The maximal enhancement of growing processes (stimulating effect) is observed when the coherence length L{sub coh} and the correlation radius r{sub cor} are greater than the cell size, i.e., the entire cell fits into the field coherence volume. In this case, the representative indicators (germination of seeds and pollen, the spears length) exceeds those of non-irradiated objects by 1.7 – 3.9 times. For more correct assessment of the effect of light statistical properties on photocontrol processes, it is proposed to replace the qualitative description (coherent – incoherent) with the quantitative one, using the determination of spatial and temporal correlation functions and comparing them with the characteristic dimensions of the biological structures, e.g., the cell size. (biophotonics)

  3. Relations between integrated and monochromatic luminosities of flat-spectrum radio quasars

    Institute of Scientific and Technical Information of China (English)

    Zhi-Fu Chen; Zhao-Yu Chen; Yi-Ping Qin; Min-Feng Gu; Lian-Zhong Lü; Cheng-Yue Su; You-Bing Li; Ye Chen

    2011-01-01

    We employ a sample of 362 flat-spectrum radio quasars (FSRQs) to calculate their integrated luminosities by integrating the spectral energy distribution (SED) constructed with multi-band (radio, IR, optical, UV and X-ray) data.We compare these luminosities with those estimated from monochromatic luminosities by multiplying them by the conventional bolometric correction factors.Our analysis shows that the integrated luminosities calculated from the SED are much larger than the bolometric luminosities estimated from monochromatic luminosities.Their departing behavior tightly correlates with radio luminosities.The relations between integrated and monochromatic luminosities are explored, which are regarded as empirical relations that might be more suitable to be applied to estimate integrated luminosities of FSRQs from their monochromatic luminosities.

  4. Dual energy computed tomography quantification of carotid plaques calcification: comparison between monochromatic and polychromatic energies with pathology correlation

    Energy Technology Data Exchange (ETDEWEB)

    Mannelli, Lorenzo [University of Washington, Departments of Radiology, Seattle, WA (United States); Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY (United States); MacDonald, Lawrence; Ferguson, Marina; Shuman, William P.; Xu, Dongxiang; Yuan, Chun; Mitsumori, Lee M. [University of Washington, Departments of Radiology, Seattle, WA (United States); Mancini, Marcello; Ragucci, Monica; Monti, Serena [IRCCS Fondazione SDN, Naples (Italy)

    2015-05-01

    We compared carotid plaque calcification detection sensitivity and apparent cross-sectional area on CT as a function of CT beam energy using conventional CT techniques and virtual mono-energetic CT images generated from dual-energy acquisitions. Five ex-vivo carotid endarterectomy (CEA) specimens were imaged with dual-energy computed tomography. Virtual monochromatic spectrum (VMS) CT images were reconstructed at energies between 40-140 keV. The same specimens were imaged using conventional polyenergetic spectrum (PS) CT with peak beam energies 80, 100, 120, and 140 kVp. The histological calcium areas on each corresponding CEA specimen were traced manually on digitized images of Toluidine-Blue/Basic-Fuchsin stained plastic sections. 40 keV VMS CT images provided high detection sensitivity (97 %) similar to conventional PS CT images (∝96 %). The calcification size measured on CT decreased systematically with increasing CT beam energy; the rate of change was larger for the VMS images than for PS images. From a single dual-energy CT, multiple VMS-CT images can be generated, yielding equivalent detection sensitivity and size correlations as conventional PS-CT in CEA calcification imaging. VMS-CT at 80-100 keV provided the most accurate estimates of calcification size, as compared to histology, but detection sensitivity was reduced for smaller calcifications on these images. (orig.)

  5. Emission of monochromatic microwave radiation from a nonequilibrium condensation of excited magnons

    OpenAIRE

    Vannucchi, FS; Vasconcellos, AR; Luzzi,R.

    2013-01-01

    The observation of monochromatic emission of radiation from a nonequilibrium Bose-Einstein-like condensate of magnons suggests the possibility of creating a monochromatic microwave generator pumped by incoherent broadband sources. The device would have a tunable emitted frequency as a function of the applied constant magnetic field. We present an analysis of the mechanisms of interaction between the condensate of magnons and the radiation field producing the super-radiant emission of photons....

  6. SR front ends of VEPP-4M storage ring

    CERN Document Server

    Fedotov, M G; Kuz'minykh, V S; Mironenko, L A; Mishnev, S I; Panchenko, V E; Protopopov, I Ya; Rachkova, V V; Rukhlyada, L P; Selivanov, A N

    2001-01-01

    The VEPP-4M storage ring system of SR front ends is described. SR is released by means of 14 front ends. Eleven of them are intended for beamlines of experimental stations. One front end is technical. For the permanent stabilization of an orbit of a beam with respect to a coordinate and angle in the vertical direction, two monitoring front ends are used. They take out SR from emission regions, which are at a large distance from one another.

  7. Monochromatic 4-term arithmetic progressions in 2-colorings of $\\mathbb Z_n$

    CERN Document Server

    Lu, Linyuan

    2011-01-01

    This paper is motivated by a recent result of Wolf \\cite{wolf} on the minimum number of monochromatic 4-term arithmetic progressions(4-APs, for short) in $\\Z_p$, where $p$ is a prime number. Wolf proved that there is a 2-coloring of $\\Z_p$ with 0.000386% fewer monochromatic 4-APs than random 2-colorings; the proof is probabilistic and non-constructive. In this paper, we present an explicit and simple construction of a 2-coloring with 9.3% fewer monochromatic 4-APs than random 2-colorings. This problem leads us to consider the minimum number of monochromatic 4-APs in $\\Z_n$ for general $n$. We obtain both lower bound and upper bound on the minimum number of monochromatic 4-APs in all 2-colorings of $\\Z_n$. Wolf proved that any 2-coloring of $\\Z_p$ has at least $(1/16+o(1))p^2$ monochromatic 4-APs. We improve this lower bound into $(7/96+o(1))p^2$. Our results on $\\Z_n$ naturally apply to the similar problem on $[n]$ (i.e., $\\{1,2,..., n\\}$). In 2008, Parillo, Robertson, and Saracino \\cite{prs} constructed a 2-...

  8. A multipurpose tunable source of monochromatic X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Chesta, M.A.; Plivelic, T.S.; Mainardi, R.T. E-mail: mainardi@mail.famaf.unc.edu.ar

    2002-02-01

    The emission of characteristic X-rays from any chemical element induced by beta particles of high energy (10{sup 5}-10{sup 6} eV) is much higher than photon excitation, with the possible exception of selective excitation. This work describes the properties of a variable energy X-ray generator that uses {sup 90}Sr as a source of beta particles and a multitarget array in a transparent source geometry. This compact device provides, through suitable selection of the target material, over 30 monoenergetic lines spread uniformly in the energy range of between 6 and 100 keV. The X-ray photon flux thus generated has an intensity of between 10{sup 2}-10{sup 3} s{sup -1} sr{sup -1} per MBq of the beta source activity. With this single beta source, the X-ray yield is higher as compared with generators using {sup 241}Am or other X- or gamma-ray sources with the same activity, and the line's intensity changes by less than a factor of three over the whole energy range.

  9. Characteristics of a multi-keV monochromatic point x-ray source based on vacuum diode with laser-produced plasma as cathode

    Indian Academy of Sciences (India)

    A Moorti; A Raghuramaiah; P A Naik; P D Gupta

    2004-11-01

    Temporal, spatial and spectral characteristics of a multi-keV monochromatic point x-ray source based on vacuum diode with laser-produced plasma as cathode are presented. Electrons from a laser-produced aluminium plasma were accelerated towards a conical point tip titanium anode to generate K-shell x-ray radiation. Approximately 1010 photons/pulse were generated in x-ray pulses of ∼ 18 to ∼ 28 ns duration from a source of ∼ 300 m diameter, at ℎ = 4.51 keV ( emission of titanium), with a brightness of ∼ 1020 photons/cm2 /s/sr. This was sufficient to record single-shot x-ray radiographs of physical objects on a DEF-5 x-ray film kept at a distance of up to ∼ 10 cm.

  10. Fast tomography using quasi-monochromatic undulator radiation.

    Science.gov (United States)

    Uesugi, Kentaro; Sera, Toshihiro; Yagi, Naoto

    2006-09-01

    A beamline with a helical undulator has been used without a monochromator for fast high-resolution tomographic imaging with an X-ray energy of 12.4-16.5 keV and an energy bandwidth of 2-3%. The X-ray beam was expanded with two mirrors to 12 mm x 4 mm. The X-ray field was made uniform by a diffuser. The detector pixel size was 9.9 microm x 9.9 microm. At the highest speed, a 180 degrees scan was completed in 6 s with 454 projections. Beam-hardening effects were not significant. This technique may be useful in studying time-dependent structural changes of soft materials such as polymers and biological samples.

  11. Synthesis, crystal structure, and TEM analysis of Sr19Li44 and Sr3Li2: a reinvestigation of the Sr-Li phase diagram.

    Science.gov (United States)

    Smetana, Volodymyr; Kienle, Lorenz; Duppel, Viola; Simon, Arndt

    2015-02-02

    Two intermetallic phases in the Sr-Li system have been synthesized and structurally characterized. According to single-crystal X-ray diffraction data, Sr(19)Li(44) and Sr(3)Li(2) crystallize with tetragonal unit cells (Sr(19)Li(44), I-42d, a = 15.9122(7) Å, c = 31.831(2) Å, Z = 4, V = 8059(2) Å(3); Sr(3)Li(2), P42/mnm, a = 9.803(1) Å, c = 8.784(2) Å, Z = 4, V = 844.2(2) Å(3)). The first compound is isostructural with the recently discovered Ba(19)Li(44). Sr in Sr(19)Li(44) can be fully replaced by Ba with no changes to the crystal structure, whereas the substitution of Sr by Ca is only possible within a limited concentration range. Sr(3)Li(2) can be assigned to the Al(2)Zr(3) structure type. The crystal structure determination of Sr(19)Li(44) was complicated by multiple twinning. As an experimental highlight, an electron microscopy investigation of the highly moisture- and electron-beam-sensitive crystals was performed, enabling high-resolution imaging of the defect structure.

  12. A mirror for lab-based quasi-monochromatic parallel x-rays.

    Science.gov (United States)

    Nguyen, Thanhhai; Lu, Xun; Lee, Chang Jun; Jung, Jin-Ho; Jin, Gye-Hwan; Kim, Sung Youb; Jeon, Insu

    2014-09-01

    A multilayered parabolic mirror with six W/Al bilayers was designed and fabricated to generate monochromatic parallel x-rays using a lab-based x-ray source. Using this mirror, curved bright bands were obtained in x-ray images as reflected x-rays. The parallelism of the reflected x-rays was investigated using the shape of the bands. The intensity and monochromatic characteristics of the reflected x-rays were evaluated through measurements of the x-ray spectra in the band. High intensity, nearly monochromatic, and parallel x-rays, which can be used for high resolution x-ray microscopes and local radiation therapy systems, were obtained.

  13. A mirror for lab-based quasi-monochromatic parallel x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Thanhhai; Lu, Xun; Lee, Chang Jun; Jeon, Insu, E-mail: i-jeon@chonnam.ac.kr [School of Mechanical Engineering, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju 500-757 (Korea, Republic of); Jung, Jin-Ho [Pro-optics Co., Ltd., 475 Ami-ri, Bubal-eup, Icheon 467-866 (Korea, Republic of); Jin, Gye-Hwan [Department of Radiology, Nambu University, 76 Chumdan Jungang 1-ro, Gwangsan-gu, Gwangju 506-706 (Korea, Republic of); Kim, Sung Youb [School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology, 100 Banyeon-ri, Eonyang-eup, Ulju-gun, Ulsan 689-798 (Korea, Republic of)

    2014-09-15

    A multilayered parabolic mirror with six W/Al bilayers was designed and fabricated to generate monochromatic parallel x-rays using a lab-based x-ray source. Using this mirror, curved bright bands were obtained in x-ray images as reflected x-rays. The parallelism of the reflected x-rays was investigated using the shape of the bands. The intensity and monochromatic characteristics of the reflected x-rays were evaluated through measurements of the x-ray spectra in the band. High intensity, nearly monochromatic, and parallel x-rays, which can be used for high resolution x-ray microscopes and local radiation therapy systems, were obtained.

  14. Cycles and transitivity by monochromatic paths in arc-coloured digraphs

    Directory of Open Access Journals (Sweden)

    Enrique Casas-Bautista

    2015-11-01

    The result by Sands et al. (1982 that asserts: Every 2-coloured digraph has a kernel by monochromatic paths, and the result by Galeana-Sánchez et al. (2011 that asserts: If D is a finite m-coloured digraph that admits a partition {C1,C2} of the set of colours of D such that for each i∈{1,2} every cycle in the subdigraph D[Ci] spanned by the arcs with colours in Ci is monochromatic, C(D does not contain neither rainbow triangles nor rainbow P3⃗ (path of length 3 involving colours of both C1 and C2; then D has a kernel by monochromatic paths.

  15. Optimal Source Tracking and Beaming of LISA

    CERN Document Server

    Pai, A

    2007-01-01

    We revisit the directionally optimal data streams of LISA first introduced in Nayak etal. It was shown that by using appropriate choice of Time delay interferometric (TDI) combinations, a monochromatic fixed source in the barycentric frame can be optimally tracked in the LISA frame. In this work, we study the beaming properties of these optimal streams. We show that all the three streams V+, Vx and Vo with maximum, minimum and zero directional SNR respectively are highly beamed. We study in detail the frequency dependence of the beaming.

  16. Note on 2-edge-colorings of complete graphs with small monochromatic k-connected subgraphs

    Institute of Scientific and Technical Information of China (English)

    JIN Ze-min; WANG Yu-ling; WEN Shi-li

    2014-01-01

    Bollob´as and Gy´arf´as conjectured that for n > 4(k-1) every 2-edge-coloring of Kn contains a monochromatic k-connected subgraph with at least n-2k+2 vertices. Liu, et al. proved that the conjecture holds when n ≥ 13k-15. In this note, we characterize all the 2-edge-colorings of Kn where each monochromatic k-connected subgraph has at most n-2k+2 vertices for n≥13k-15.

  17. Implementation of dual-energy technique for virtual monochromatic and linearly mixed CBCTs

    Energy Technology Data Exchange (ETDEWEB)

    Li Hao; Giles, William; Ren Lei; Bowsher, James; Yin Fangfang [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2012-10-15

    Purpose: To implement dual-energy imaging technique for virtual monochromatic (VM) and linearly mixed (LM) cone beam CTs (CBCTs) and to demonstrate their potential applications in metal artifact reduction and contrast enhancement in image-guided radiation therapy (IGRT). Methods: A bench-top CBCT system was used to acquire 80 kVp and 150 kVp projections, with an additional 0.8 mm tin filtration. To implement the VM technique, these projections were first decomposed into acrylic and aluminum basis material projections to synthesize VM projections, which were then used to reconstruct VM CBCTs. The effect of VM CBCT on the metal artifact reduction was evaluated with an in-house titanium-BB phantom. The optimal VM energy to maximize contrast-to-noise ratio (CNR) for iodine contrast and minimize beam hardening in VM CBCT was determined using a water phantom containing two iodine concentrations. The LM technique was implemented by linearly combining the low-energy (80 kVp) and high-energy (150 kVp) CBCTs. The dose partitioning between low-energy and high-energy CBCTs was varied (20%, 40%, 60%, and 80% for low-energy) while keeping total dose approximately equal to single-energy CBCTs, measured using an ion chamber. Noise levels and CNRs for four tissue types were investigated for dual-energy LM CBCTs in comparison with single-energy CBCTs at 80, 100, 125, and 150 kVp. Results: The VM technique showed substantial reduction of metal artifacts at 100 keV with a 40% reduction in the background standard deviation compared to a 125 kVp single-energy scan of equal dose. The VM energy to maximize CNR for both iodine concentrations and minimize beam hardening in the metal-free object was 50 keV and 60 keV, respectively. The difference of average noise levels measured in the phantom background was 1.2% between dual-energy LM CBCTs and equivalent-dose single-energy CBCTs. CNR values in the LM CBCTs of any dose partitioning are better than those of 150 kVp single-energy CBCTs. The

  18. Preliminary design of the advanced quantum beam source

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Cheol; Lee, Jong Min; Jeong, Young Uk; Cho, Sung Oh; Yoo, Jae Gwon; Park, Seong Hee

    2000-07-01

    The preliminary design of the advanced quantum beam source based on a superconducting electron accelerator is presented. The advanced quantum beams include: high power free electron lasers, monochromatic X-rays and {gamma}-rays, high-power medium-energy electrons, high-flux pulsed neutrons, and high-flux monochromatic slow positron beam. The AQBS system is being re-designed, assuming that the SPS superconducting RF cavities used for LEP at CERN will revived as a main accelerator of the AQBS system at KAERI, after the decommissioning of LEP at the end of 2000. Technical issues of using the SPS superconducting RF cavities for the AQBS project are discussed in this report. The advanced quantum beams will be used for advanced researches in science and industries.

  19. Effect of a combination of green and blue monochromatic light on broiler immune response.

    Science.gov (United States)

    Zhang, Ziqiang; Cao, Jing; Wang, Zixu; Dong, Yulan; Chen, Yaoxing

    2014-09-05

    Our previous study suggested that green light or blue light would enhance the broiler immune response; this study was conducted to evaluate whether a combination of green and blue monochromatic light would result in improved immune response. A total of 192 Arbor Acre male broilers were exposed to white light, red light, green light, and blue light from 0 to 26 days. From 27 to 49 days, half of the broilers in green light and blue light were switched to blue light (G-B) and green light (B-G), respectively. The levels of anti-Newcastle disease virus (NDV) and anti-bovine serum albumin (BSA) IgG in G-B group were elevated by 11.9-40.3% and 17.4-48.7%, respectively, compared to single monochromatic lights (Plight groups. However, the serum TNF-α concentration in the G-B group was reduced by 3.64-40.5% compared to other groups, and no significant difference was found between the G-B and B-G groups in any type of detection index at the end of the experiment. These results suggested that the combination of G-B and B-G monochromatic light could effectively enhance the antibody titer, the proliferation index of lymphocytes and alleviate the stress response in broilers. Therefore, the combination of green and blue monochromatic light can improve the immune function of broilers. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Pustular Palmoplantar Psoriasis Successfully Treated with Nb-UVB Monochromatic Excimer Light: A Case-Report

    Directory of Open Access Journals (Sweden)

    Serena Gianfaldoni

    2017-07-01

    Full Text Available Barber’s palmoplantar pustulosis (PPP is a form of localised pustular psoriasis, affecting the palmar and plantar surfaces. It is a chronic disease, with a deep impact on the patients’ quality of life. The Authors discuss a case of Baber Psoriasis successfully treated with monochromatic excimer light.

  1. Resonant three-photon ionization of hydrogenic atoms by a non-monochromatic laser field

    NARCIS (Netherlands)

    Yakhontov, V.; Santra, R.; Jungmann, K.

    1999-01-01

    We present ionization probability and lineshape calculations for the two-step three- photon ionization process, 1S (2(h)over-bar-omega)under-right-arrow, 2S ((h)over-bar-omega)under-right-arrow epsilon P, of the ground state of hydrogenic atoms in a non-monochromatic laser field with a time-dependen

  2. Resonant three-photon ionization of hydrogenic atoms by a non-monochromatic laser field

    NARCIS (Netherlands)

    Yakhontov, V.; Santra, R.; Jungmann, K.

    1999-01-01

    We present ionization probability and lineshape calculations for a specifed two-step three-photon ionization process of the ground state of hydrogenic atoms in a non-monochromatic laser field with a time-dependent amplitude. Within the framework of a three-level model, the AC Stark shifts and non-ze

  3. Broadband EM radiation amplification by means of a monochromatically driven two-level system

    Science.gov (United States)

    Soldatov, Andrey V.

    2017-02-01

    It is shown that a two-level quantum system possessing dipole moment operator with permanent non-equal diagonal matrix elements and driven by external semiclassical monochromatic high-frequency electromagnetic (EM) (laser) field can amplify EM radiation waves of much lower frequency.

  4. Gamma beam system at ELI-NP

    Energy Technology Data Exchange (ETDEWEB)

    Ur, Calin Alexandru, E-mail: calin.ur@eli-np.ro [Extreme Light Infrastructure, IFIN-HH, Magurele-Bucharest (Romania)

    2015-02-24

    The Gamma Beam System of ELI-NP will produce brilliant, quasi-monochromatic gamma-ray beams via Inverse Compton Scattering of short laser pulses on relativistic electron beam pulses. The scattered radiation is Doppler upshifted by more than 1,000,000 times and is forward focused in a narrow, polarized, tunable, laser-like beam. The gamma-ray beam at ELI-NP will be characterized by large spectral density of about 10{sup 4} photons/s/eV, narrow bandwidth (< 0.5%) and tunable energy from 200 keV up to about 20 MeV. The Gamma Beam System is a state-of-the-art equipment employing techniques and technologies at the limits of the present-day's knowledge.

  5. Analysis and interpretation of the first monochromatic X-ray tomography data collected at the Australian Synchrotron Imaging and Medical beamline.

    Science.gov (United States)

    Stevenson, Andrew W; Hall, Christopher J; Mayo, Sheridan C; Häusermann, Daniel; Maksimenko, Anton; Gureyev, Timur E; Nesterets, Yakov I; Wilkins, Stephen W; Lewis, Robert A

    2012-09-01

    The first monochromatic X-ray tomography experiments conducted at the Imaging and Medical beamline of the Australian Synchrotron are reported. The sample was a phantom comprising nylon line, Al wire and finer Cu wire twisted together. Data sets were collected at four different X-ray energies. In order to quantitatively account for the experimental values obtained for the Hounsfield (or CT) number, it was necessary to consider various issues including the point-spread function for the X-ray imaging system and harmonic contamination of the X-ray beam. The analysis and interpretation of the data includes detailed considerations of the resolution and efficiency of the CCD detector, calculations of the X-ray spectrum prior to monochromatization, allowance for the response of the double-crystal Si monochromator used (via X-ray dynamical theory), as well as a thorough assessment of the role of X-ray phase-contrast effects. Computer simulations relating to the tomography experiments also provide valuable insights into these important issues. It was found that a significant discrepancy between theory and experiment for the Cu wire could be largely resolved in terms of the effect of the point-spread function. The findings of this study are important in respect of any attempts to extract quantitative information from X-ray tomography data, across a wide range of disciplines, including materials and life sciences.

  6. Mapping the Ionization State of Laser-Irradiated Ar Gas Jets With Multi-Wavelength Monochromatic X-Ray Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kugland, N L; Doppner, T; Kemp, A; Schaeffer, D; Glenzer, S H; Niemann, C

    2010-04-08

    Two-dimensional monochromatic images of fast-electron stimulated Ar K{alpha} and He-{alpha} x-ray self-emission have recorded a time-integrated map of the extent of Ar{sup {approx}6+} and Ar{sup 16+} ions, respectively, within a high density (10{sup 20} cm{sup -3} atomic density) Ar plasma. This plasma was produced by irradiating a 2 mm wide clustering Ar gas jet with an ultra-high intensity (10{sup 19} W/cm{sup 2}, 200 fs) Ti:Sapphire laser operating at 800 nm. Spherically bent quartz crystals in the 200 (for K{alpha}) and 201 (for He-{alpha}) planes were used as near-normal incidence reflective x-ray optics. We see that a large (830 {micro}m long) region of plasma emits K{alpha} primarily along the laser axis, while the He-{alpha} emission is confined to smaller hot spot (230 {micro}m long) region that likely corresponds to the focal volume of the f/8 laser beam. X-ray spectra from a Bragg spectrometer operating in the von Hamos geometry, which images in one dimension, indicate that the centroids of the K{alpha} and He-{alpha} emission regions are separated by approximately 330 {micro}m along the laser axis.

  7. On Analytical Solutions to Beam-Hardening

    Science.gov (United States)

    Rigaud, G.

    2017-01-01

    When polychromatic X-rays propagate through a material, for instance in computerized tomography (CT), low energy photons are more attenuated resulting in a "harder" beam. The beam-hardening phenomenon breaks the monochromatic radiation model based on the Radon transform giving rise to artifacts in CT reconstructions to the detriment of visual inspection and automated segmentation algorithms. We propose first a simplified analytic representation for the beam-hardening. Besides providing a general understanding of the phenomenon, this model proposes to invert the beam-hardening effect for homogeneous objects leading to classical monochromatic data. For heterogeneous objects, no analytical reconstruction of the density can be derived without more prior information. However, the beam-hardening is shown to be a smooth operation on the data and thus to preserve the encoding of the singularities of the attenuation map within the data. A microlocal analysis encourages the use of contour extraction methods to solve partially the beam-hardening effect even for heterogeneous objects. The application of both methods, exact analytical solution for homogeneous objects and feature extraction for heterogeneous ones, on real data demonstrates their relevancy and efficiency.

  8. A beam expander facility for studying x-ray optics

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Hornstrup, Allan; Frederiksen, P.

    1992-01-01

    The detailed study of the performance of full scale x-ray optics often requires the illumination of large areas. This paper describes a beam expander facility at the Daresbury Synchrotron Radiation Facility. It combines monochromatization and beam expansion in one dimension. The beam expansion...... is obtained from an extremely asymmetric reflection in a large single crystal of Si. An expansion of a factor of 50 was obtained in one dimension. The expanded beam of ~85 mm is limited only by the crystal size. The facility is installed in a 12-m-long hutch. A specific application, in which a high throughput...

  9. A Laue–Bragg monolithic beam splitter for efficient X-ray 2-beam imaging

    Energy Technology Data Exchange (ETDEWEB)

    Oberta, P., E-mail: peter.oberta@rigaku.com [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i., Na Slovance 2, CZ-18221 Praha 8 (Czech Republic); Mokso, R. [Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen (Switzerland)

    2013-03-01

    Newly emerging techniques for probing matter simultaneously by two spatially and angularly separated X-ray beams require efficient and versatile beam splitting. We present a Laue–Bragg monolithic crystal beam splitter in the form of an L-shaped monolithic Si crystal. By simultaneous Laue and Bragg diffractions the X-ray beam is split into a transmitted polychromatic and a diffracted monochromatic branch with a spatial separation of tens of millimeters. The energy spectrum of the transmitted branch can be tuned via diffraction on a second crystal re-creating a beam intersection on the sample. We propose three multi-modal imaging setups exploiting the large angular separation of the two intersecting beams provided by the proposed optics. Photon efficiency and dual-energy operation are the main assets of our scheme as compared to other existing setups. The theoretical description for an energy range between 10 keV and 30 keV was developed.

  10. Monochromatic imaging instrumentation for applications in aeronomy of the earth and planets

    Science.gov (United States)

    Baumgardner, Jeffrey; Flynn, Brian; Mendillo, Michael

    1992-01-01

    Monochromatic imaging instrumentation has been developed that uses narrow-band (12 A FWHP) interference filters or plane reflection gratings for 2D imaging and imaging spectrograph applications. By changing the optics in front of the filter or grating, the field of view of the instruments can be varied from 180 deg to 6 deg. In the case of the 2D monochromatic imager, the 12 mm-diameter filtered image is formed at about f/1 on the input photocathode of an intensified CCD camera (380 x 488 pixels). The sensitivities of the systems are about 50-100 R s (S/N about 2). Examples of data taken with both of these instruments include detection and mapping of Jupiter's sodium magnetonebula and stable auroral red arcs in the terrestrial ionosphere.

  11. Monochromatic wavelength dispersive x-ray fluorescence providing sensitive and selective detection of uranium

    Energy Technology Data Exchange (ETDEWEB)

    Havrilla, George J [Los Alamos National Laboratory; Collins, Michael L [Los Alamos National Laboratory; Montoya, Velma M [Los Alamos National Laboratory; Chen, Zewu [XOS; Wei, Fuzhong [XOS

    2010-01-01

    Monochromatic wavelength dispersive X-ray fluorescence (MWDXRF) is a sensitive and selective method for elemental compositional analyses. The basis for this instrumental advance is the doubly curved crystal (DCC) optic. Previous work has demonstrated the feasibility of sensitive trace element detection for yttrium as a surrogate for curium in aqueous solutions. Additional measurements have demonstrated similar sensitivity in several different matrix environments which attests to the selectivity of the DCC optic as well as the capabilities of the MWDXRF concept. The objective of this effort is to develop an improved Pu characterization method for nuclear fuel reprocessing plants. The MWDXRF prototype instrument is the second step in a multi-year effort to achieve an improved Pu assay. This work will describe a prototype MWDXRF instrument designed for uranium detection and characterization. The prototype consists of an X-ray tube with a rhodium anode and a DCC excitation optic incorporated into the source. The DCC optic passes the RhK{alpha} line at 20.214 keV for monochromatic excitation of the sample. The source is capable of 50 W power at 50 kV and 1.0 mA operation. The x-ray emission from the sample is collected by a DCC optic set at the UL{alpha} line of 13.613 keV. The collection optic transmits the UL{alpha} x-rays to the silicon drift detector. The x-ray source, sample, collection optic and detector are all mounted on motion controlled stages for the critical alignment of these components. The sensitivity and selectivity of the instrument is obtained through the monochromatic excitation and the monochromatic detection. The prototype instrument performance has a demonstrated for sensitivity for uranium detection of around 2 ppm at the current state of development. Further improvement in sensitivity is expected with more detailed alignment.

  12. In-ovo monochromatic green light photostimulation enhances embryonic somatotropic axis activity.

    Science.gov (United States)

    Dishon, L; Avital-Cohen, N; Malamud, D; Heiblum, R; Druyan, S; Porter, T E; Gumulka, M; Rozenboim, I

    2017-06-01

    Previous studies demonstrated that in ovo photostimulation with monochromatic green light increases body weight and accelerates muscle development in broilers. The mechanism in which in ovo photostimulation accelerates growth and muscle development is not clearly understood. The objective of the current study was to define development of the somatotropic axis in the broiler embryo associated with in ovo green light photostimulation. Two-hundred-forty fertile broiler eggs were divided into 2 groups. The first group was incubated under intermittent monochromatic green light using light-emitting diode (LED) lamps with an intensity of 0.1 W\\m2 at shell level, and the second group was incubated under dark conditions and served as control. In ovo green light photostimulation increased plasma growth hormone (GH) and prolactin (PRL) levels, as well as hypothalamic growth hormone releasing hormone (GHRH), liver growth hormone receptor (GHR), and insulin-like growth factor-1 (IGF-1) mRNA levels. The in ovo photostimulation did not, however, increase embryo's body weight, breast muscle weight, or liver weight. The results of this study suggest that stimulation with monochromatic green light during incubation increases somatotropic axis expression, as well as plasma prolactin levels, during embryonic development. © 2017 Poultry Science Association Inc.

  13. Dichromatic and monochromatic laser radiation effects on survival and morphology of Pantoea agglomerans

    Science.gov (United States)

    Thomé, A. M. C.; Souza, B. P.; Mendes, J. P. M.; Soares, L. C.; Trajano, E. T. L.; Fonseca, A. S.

    2017-05-01

    Despite the beneficial effects of low-level lasers on wound healing, their application for treatment of infected injuries is controversial because low-level lasers could stimulate bacterial growth exacerbating the infectious process. Thus, the aim of this work was to evaluate in vitro effects of low-level lasers on survival, morphology and cell aggregation of Pantoea agglomerans. P. agglomerans samples were isolated from human pressure injuries and cultures were exposed to low-level monochromatic and simultaneous dichromatic laser radiation to study the survival, cell aggregation, filamentation and morphology of bacterial cells in exponential and stationary growth phases. Fluence, wavelength and emission mode were those used in therapeutic protocols for wound healing. Data show no changes in morphology and cell aggregation, but dichromatic laser radiation decreased bacterial survival in exponential growth phase and monochromatic red and infrared lasers increased bacterial survival at the same fluence. Simultaneous dichromatic laser radiation induces biological effects that differ from those induced by monochromatic laser radiation and simultaneous dichromatic laser could be the option for treatment of infected pressure injuries by Pantoea agglomerans.

  14. Melatonin modulates monochromatic light-induced GHRH expression in the hypothalamus and GH secretion in chicks.

    Science.gov (United States)

    Zhang, Liwei; Cao, Jing; Wang, Zixu; Dong, Yulan; Chen, Yaoxing

    2016-04-01

    To study the mechanism by which monochromatic lights affect the growth of broilers, a total of 192 newly hatched broilers, including the intact, sham-operated and pinealectomy groups, were exposed to white light (WL), red light (RL), green light (GL) and blue light (BL) using a light-emitting diode (LED) system for 2 weeks. The results showed that the GHRH-ir neurons were distributed in the infundibular nucleus (IN) of the chick hypothalamus. The mRNA and protein levels of GHRH in the hypothalamus and the plasma GH concentrations in the chicks exposed to GL were increased by 6.83-31.36%, 8.71-34.52% and 6.76-9.19% compared to those in the chicks exposed to WL (P=0.022-0.001), RL (P=0.002-0.000) and BL (P=0.290-0.017) in the intact group, respectively. The plasma melatonin concentrations showed a positive correlation with the expression of GHRH (r=0.960) and the plasma GH concentrations (r=0.993) after the various monochromatic light treatments. After pinealectomy, however, these parameters decreased and there were no significant differences between GL and the other monochromatic light treatments. These findings suggest that melatonin plays a critical role in GL illumination-enhanced GHRH expression in the hypothalamus and plasma GH concentrations in young broilers. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. Dark Matter Decay to a Photon and a Neutrino: the Double Monochromatic Smoking Gun Scenario

    CERN Document Server

    Aisati, Chaïmae El; Hambye, Thomas; Scarna, Tiziana

    2015-01-01

    In the energy range from few TeV to 25 TeV, upper bounds on the dark matter decay rate into high energy monochromatic neutrinos have recently become comparable to those on monochromatic gamma-ray lines. This implies clear possibilities of a future double "smoking-gun" evidence for the dark matter particle, from the observation of both a gamma and a neutrino line at the same energy. In particular, we show that a scenario where both lines are induced from the same dark matter particle decay leads to correlations that can already be tested. We study this "double monochromatic" scenario by considering the complete list of lowest dimensional effective operators that could induce such a decay. Furthermore, we argue that, on top of lines from decays into two-body final states, three-body final states can also be highly relevant. In addition to producing a distinct hard photon spectrum, three-body final states also produce a line-like feature in the neutrino spectrum that can be searched for by neutrino telescopes.

  16. New method of beam bunching in free-ion lasers

    Energy Technology Data Exchange (ETDEWEB)

    Bessonov, E.G. [Lebedev Physics Institute, Moscow (Russian Federation)

    1995-12-31

    An effective ion beam bunching method is suggested. This method is based on a selective interaction of line spectrum laser light (e.g. axial mode structure light) with non-fully stripped ion beam cooled in a storage rings, arranging the ion beam in layers in radial direction of an energy-longitudinal coordinate plane and following rotation of the beam at the right angle after switching on the RF cavity or undulator grouper/buncher. Laser cooling of the ion beam can be used at this position after switching off the resonator to decrease the energy spread caused by accelerating field of the resonator. A relativistic multilayer ion mirror will be produced this way. Both monochromatic laser beams and intermediate monochromaticity and bandwidth light sources of spontaneous incoherent radiation can be used for production of hard and high power electromagnetic radiation by reflection from this mirror. The reflectivity of the mirror is rather high because of the cross-section of the backward Rayleigh scattering of photon light by non-fully stripped relativistic ions ({approximately}{lambda}{sup 2}) is much greater ({approximately} 10{divided_by}15 orders) then Thompson one ({approximately} r{sub e}{sup 2}). This position is valid even in the case of non-monochromatic laser light ({Delta}{omega}/{omega} {approximately} 10{sup -4}). Ion cooling both in longitudinal plane and three-dimensional radiation ion cooling had been proposed based on this observation. The using of these cooling techniques will permit to store high current and low emittance relativistic ion beams in storage rings. The bunched ion beam can be used in ordinary Free-Ion Lasers as well. After bunching the ion beam can be extracted from the storage ring in this case. Storage rings with zero momentum compaction function will permit to keep bunching of the ion beam for a long time.

  17. Crystal growth and electronic structure of low-temperature phase SrMgF{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Atuchin, Victor V. [Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 630090 (Russian Federation); Functional Electronics Laboratory, Tomsk State University, Tomsk 634050 (Russian Federation); Laboratory of Semiconductor and Dielectric Materials, Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Goloshumova, Alina A. [Laboratory of Crystal Growth, Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Isaenko, Ludmila I. [Laboratory of Semiconductor and Dielectric Materials, Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Laboratory of Crystal Growth, Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Jiang, Xingxing [BCCRD, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Lobanov, Sergey I. [Laboratory of Crystal Growth, Institute of Geology and Mineralogy, SB RAS, Novosibirsk 630090 (Russian Federation); Zhang, Zhaoming [Australian Nuclear Science & Technology Organisation, Lucas Heights, NSW 2234 (Australia); Lin, Zheshuai, E-mail: zslin@mail.ipc.ac.cn [BCCRD, Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2016-04-15

    Using the vertical Bridgman method, the single crystal of low temperature phase SrMgF{sub 4} is obtained. The crystal is in a very good optical quality with the size of 10×7×5 mm{sup 3}. Detailed photoemission spectra of the element core levels are determined by a monochromatic AlKa (1486.6 eV) X-ray source. Moreover, the first-principles calculations are performed to investigate the electronic structure of SrMgF{sub 4}. A good agreement between experimental and calculated results is achieved. It is demonstrated that almost all the electronic orbitals are strongly localized and the hybridization with the others is very small, but the Mg–F bonds covalency is relatively stronger than that of Sr–F bonds. - Graphical abstract: Large size of low-temperature phase SrMgF{sub 4} crystal was obtained (right) and its electronic structure was investigated by X-ray photoelectron spectroscopy and first-principles calculation (left). - Highlights: • Large size single crystal of low-temperature phase SrMgF{sub 4} is obtained. • Electronic structure of SrMgF{sub 4} is measured by X-ray photoelectron spectroscopy. • Partial densities of states are determined by first-principles calculation. • Good agreement between experimental and calculated results is achieved. • Strong ionic characteristics of chemical bonds are exhibited in SrMgF{sub 4}.

  18. Bi2Sr2CaCu2O(8+δ)薄膜的分子束外延法制备及结晶性%FABRICATION AND CRYSTALLINITY OF Bi2Sr2CaCu2O(8+δ) THIN FILMS BY MOLECULAR BEAM EPITAXY

    Institute of Scientific and Technical Information of China (English)

    张炳森; 李茂林; 王晶晶; 孙本哲; 祁阳

    2009-01-01

    在BiO-(Sr+Ca)O-CuO相图上的Bi2Sr2CaCu2O8+6(Bi-2212)相附近选择不同成分,用分子束外延法制备成薄膜,利用XRD,EDS,SEM和AFM研究了成分,衬底温度和臭氧分压对Bi-2212相薄膜成相的影响,分析了生长速率和错配度对Bi-2212相薄膜质量的影响.结果表明,Bi-2212相薄膜单相生成的成分范围(原子分数)分别为Bi 26.3%-32.4%,(Sr+Ca) 37.4%-146.5%,Cu 24.8%-32.6%;当衬底温度为720℃且臭氧分压为1.3×10-3 Pa时,在MgO(100)衬底上生长出质量较高的c轴外延Bi-2212相薄膜;通过调整生长速率、更换衬底和插入不同厚度的Bi2Sr2CuO(6+δ)过渡层的方法,可以改善Bi-2212相薄膜的结晶质量.表面形貌和导电特性.

  19. Propagation of Gaussian Beams through Active GRIN Materials

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Varela, A I; Flores-Arias, M T; Bao-Varela, C; Gomez-Reino, C [Grupo de ' Microoptica y Optica GRIN' , Unidad asociada al Instituto de Ciencias de Materiales de Aragon, ICMA/CSIC, Zaragoza, Espana y Escuela de Optica y OptometrIa, Campus Sur s/n, Universidade de Santiago, E15782 Santiago de Compostela (Spain); De la Fuente, X, E-mail: maite.flores@usc.es [Instituto de Ciencia de Materiales de Aragon (Universidad de Zaragoza-CSIC), Maria de Luna 3, E50018 Zaragoza (Spain)

    2011-01-01

    We discussed light propagation through an active GRIN material that exhibits loss or gain. Effects of gain or loss in GRIN materials can be phenomenologically taken into account by using a complex refractive index in the wave equation. This work examines the implication of using a complex refractive index on light propagation in an active GRIN material illuminated by a non-uniform monochromatic wave described by a Gaussian beam. We analyze how a Gaussian beam is propagated through the active material in order to characterize it by the beam parameters and the transverse irradiance distribution.

  20. Low luminance/eyes closed and monochromatic stimulations reduce variability of flash visual evoked potential latency

    Directory of Open Access Journals (Sweden)

    Senthil Kumar Subramanian

    2013-01-01

    Full Text Available Context: Visual evoked potentials are useful in investigating the physiology and pathophysiology of the human visual system. Flash visual evoked potential (FVEP, though technically easier, has less clinical utility because it shows great variations in both latency and amplitude for normal subjects. Aim: To study the effect of eye closure, low luminance, and monochromatic stimulation on the variability of FVEPs. Subjects and Methods: Subjects in self-reported good health in the age group of 18-30 years were divided into three groups. All participants underwent FVEP recording with eyes open and with white light at 0.6 J luminance (standard technique. Next recording was done in group 1 with closed eyes, group 2 with 1.2 and 20 J luminance, and group 3 with red and blue lights, while keeping all the other parameters constant. Two trials were given for each eye, for each technique. The same procedure was repeated at the same clock time on the following day. Statistical Analysis: Variation in FVEP latencies between the individuals (interindividual variability and the variations within the same individual for four trials (intraindividual variability were assessed using coefficient of variance (COV. The technique with lower COV was considered the better method. Results: Recording done with closed eyes, 0.6 J luminance, and monochromatic light (blue > red showed lower interindividual and intraindividual variability in P2 and N2 as compared to standard techniques. Conclusions: Low luminance flash stimulations and monochromatic light will reduce FVEP latency variability and may be clinically useful modifications of FVEP recording technique.

  1. Source mechanics for monochromatic icequakes produced during iceberg calving at Columbia Glacier, AK

    Science.gov (United States)

    O'Neel, Shad; Pfeffer, W.T.

    2007-01-01

    Seismograms recorded during iceberg calving contain information pertaining to source processes during calving events. However, locally variable material properties may cause signal distortions, known as site and path effects, which must be eliminated prior to commenting on source mechanics. We applied the technique of horizontal/vertical spectral ratios to passive seismic data collected at Columbia Glacier, AK, and found no dominant site or path effects. Rather, monochromatic waveforms generated by calving appear to result from source processes. We hypothesize that a fluid-filled crack source model offers a potential mechanism for observed seismograms produced by calving, and fracture-processes preceding calving.

  2. Solar monochromatic images in magneto-sensitive spectral lines and maps of vector magnetic fields

    Science.gov (United States)

    Shihui, Y.; Jiehai, J.; Minhan, J.

    1985-01-01

    A new method which allows by use of the monochromatic images in some magneto-sensitive spectra line to derive both the magnetic field strength as well as the angle between magnetic field lines and line of sight for various places in solar active regions is described. In this way two dimensional maps of vector magnetic fields may be constructed. This method was applied to some observational material and reasonable results were obtained. In addition, a project for constructing the three dimensional maps of vector magnetic fields was worked out.

  3. Directional and monochromatic thermal emitter from epsilon-near-zero conditions in semiconductor hyperbolic metamaterials

    Science.gov (United States)

    Campione, Salvatore; Marquier, Francois; Hugonin, Jean-Paul; Ellis, A. Robert; Klem, John F.; Sinclair, Michael B.; Luk, Ting S.

    2016-01-01

    The development of novel thermal sources that control the emission spectrum and the angular emission pattern is of fundamental importance. In this paper, we investigate the thermal emission properties of semiconductor hyperbolic metamaterials (SHMs). Our structure does not require the use of any periodic corrugation to provide monochromatic and directional emission properties. We show that these properties arise because of epsilon-near-zero conditions in SHMs. The thermal emission is dominated by the epsilon-near-zero effect in the doped quantum wells composing the SHM. Furthermore, different properties are observed for s and p polarizations, following the characteristics of the strong anisotropy of hyperbolic metamaterials.

  4. Enhancing monochromatic multipole emission by a subwavelength enclosure of degenerate Mie resonances

    KAUST Repository

    Zhao, Jiajun

    2017-07-06

    Sound emission is inefficient at low frequencies as limited by source size. This letter presents enhancing emission of monochromatic monopole and multipole sources by enclosing the source with a subwavelength circular enclosure filled of an anisotropic material of a low radial sound speed. The anisotropy is associated with an infinite tangential density along the azimuth. Numerical simulations show that emission gain is produced at frequencies surrounding degenerate Mie resonant frequencies of the enclosure, and meanwhile the radiation directivity pattern is well preserved. The degeneracy is theoretically analyzed. A realization of the material is suggested by using a space-coiling structure.

  5. Response of vegetable organisms to quasi-monochromatic light of different duration, intensity and wavelength

    Energy Technology Data Exchange (ETDEWEB)

    Budagovsky, A V; Solovykh, N V [I.V.Michurin All-Russian Recearch Institute of Fruit Crops Genetics and Breeding (Russian Federation); Budagovskaya, O N [I.V.Michurin All-Russia Research and Development Institute of Gardening, Michurinsk, Tambov region (Russian Federation); Budagovsky, I A [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2015-04-30

    By the example of vegetable organisms differing in structure and functional properties it is shown that their response to the action of quasi-monochromatic light from laser sources does not obey the Bunsen – Roscoe dose law. The dependence of biological effect on the irradiation time has the multimodal (multiextremal) form with alternating maxima and minima of the stimulating effect. Such a property manifests itself in the spectral ranges, corresponding to photoinduced conversion of chromoproteins of photocontrol systems and is probably related to the cyclic variations of metabolic activity in vegetable cells. (biophotonics)

  6. Display of the complex degree of coherence due to quasi-monochromatic spatially incoherent sources.

    Science.gov (United States)

    Michalski, M; Sicre, E E; Rabal, H J

    1985-12-01

    A method for displaying the complex degree of coherence (CDC) of a quasi-monochromatic spatially incoherent source is proposed. The phase of the CDC is encoded in a method similar to that used in interferometric imaging with incoherent light. The method is based on Fourier analysis of the speckle pattern that appears when a diffuser is illuminated with the partially coherent field whose CDC is to be displayed. In addition, an intensity pattern that resembles the spatial distribution of the incoherent source can also be obtained.

  7. A monochromatic x-ray imaging system for characterizing low-density foams

    Energy Technology Data Exchange (ETDEWEB)

    Lanier, Nicholas E. [Los Alamos National Laboratory; Taccetti, Jose M. [Los Alamos National Laboratory; Hamilton, Christopher E. [Los Alamos National Laboratory

    2012-05-04

    In High Energy Density (HED) laser experiments, targets often require small, low-density, foam components. However, their limited size can preclude single component characterization, forcing one to rely solely on less accurate bulk measurements. We have developed a monochromatic imaging a system to characterize both the density and uniformity of single component low-mass foams. This x-ray assembly is capable of determining line-averaged density variations near the 1% level, and provides statistically identical results to those obtained at the Brookhaven's NSLS. This system has the added benefit of providing two-dimensional density data, allowing an assessment of density uniformity.

  8. Directional and monochromatic thermal emitter from epsilon-near-zero conditions in semiconductor hyperbolic metamaterials

    Science.gov (United States)

    Campione, Salvatore; Marquier, Francois; Hugonin, Jean-Paul; Ellis, A. Robert; Klem, John F.; Sinclair, Michael B.; Luk, Ting S.

    2016-10-01

    The development of novel thermal sources that control the emission spectrum and the angular emission pattern is of fundamental importance. In this paper, we investigate the thermal emission properties of semiconductor hyperbolic metamaterials (SHMs). Our structure does not require the use of any periodic corrugation to provide monochromatic and directional emission properties. We show that these properties arise because of epsilon-near-zero conditions in SHMs. The thermal emission is dominated by the epsilon-near-zero effect in the doped quantum wells composing the SHM. Furthermore, different properties are observed for s and p polarizations, following the characteristics of the strong anisotropy of hyperbolic metamaterials.

  9. SR study of scintillators

    CERN Document Server

    Mikhailin, V V

    2000-01-01

    The technique and the models developed recently in Synchrotron Radiation (SR) Laboratory of Moscow University for the investigation of energy transfer processes in insulators can be applied for a detailed study of scintillator's properties. The experiments with SR in VUV and XUV regions allow to separate various processes and stages of energy transfer and help to indicate the dominating process on each stage. Thus, we can find the way to improve the properties, essential for the particular application of the scintillator: conversion efficiency, decay time, afterglow, radiation hardness, etc. The results of such a study can be used for the testing procedures in scintillator production.

  10. Thermal response of photovoltaic cell to laser beam irradiation

    OpenAIRE

    Yuan, Yu-Chen; Wu, Chen-Wu

    2014-01-01

    This paper firstly presents the concept of using dual laser beam to irradiate the photovoltaic cell, so as to investigate the temperature dependency of the efficiency of long distance energy transmission. Next, the model on the multiple reflection and absorption of any monochromatic light in multilayer structure has been established, and the heat generation in photovoltaic cell has been interpreted in this work. Then, the finite element model has been set up to calculate the temperature of ph...

  11. Statistical analysis of ocular monochromatic aberrations in Chinese population for adaptive optics ophthalmoscope design

    Directory of Open Access Journals (Sweden)

    Junlei Zhao

    2017-01-01

    Full Text Available It is necessary to know the distribution of the Chinese eye’s aberrations in clinical environment to guide high-resolution retinal imaging system design for large Chinese population application. We collected the monochromatic wave aberration of 332 healthy eyes and 344 diseased eyes in Chinese population across a 6.0-mm pupil. The aberration statistics of Chinese eyes including healthy eyes and diseased eyes were analyzed, and some differences of aberrations between the Chinese and European race were concluded. On this basis, the requirement for adaptive optics (AO correction of the Chinese eye’s monochromatic aberrations was analyzed. The result showed that a stroke of 20μm and ability to correct aberrations up to the 8th Zernike order were needed for reflective wavefront correctors to achieve near diffraction-limited imaging in both groups for a reference wavelength of 550nm and a pupil diameter of 6.0mm. To verify the analysis mentioned above, an AO flood-illumination system was established, and high-resolution retinal imaging in vivo was achieved for Chinese eye including both healthy and diseased eyes.

  12. Dual-energy tissue cancellation in mammography with quasi-monochromatic x-rays.

    Science.gov (United States)

    Marziani, M; Taibi, A; Tuffanelli, A; Gambaccini, M

    2002-01-21

    Dual-energy radiography has not evolved into a routine clinical examination yet due to intrinsic limitations of both dual-kVp imaging and single-exposure imaging with conventional x-ray sources. The recent introduction of novel quasi-monochromatic x-ray sources and detectors could lead to interesting improvements, especially in mammography where the complex structure of healthy tissues often masks the detectability of lesions. A dual-energy radiography technique based on a tissue cancellation algorithm has been developed for mammography, with the aim of maximizing the low intrinsic contrast of pathologic tissues while being able to minimize or cancel the contrast between glandular and fat tissues. Several images of a plastic test object containing various tissue equivalent inserts were acquired in the energy range 17-36 keV using a quasi-monochromatic x-ray source and a scintillator-coated CCD detector. Images acquired at high and low energies were nonlinearly combined to generate two energy-independent basis images. Suitable linear combinations of these two basis images result in the elimination of the contrast of a given material with respect to another. This makes it possible to selectively cancel certain details in the processed image.

  13. Frequency-locked pulse sequencer for high-frame-rate monochromatic tissue motion imaging.

    Science.gov (United States)

    Azar, Reza Zahiri; Baghani, Ali; Salcudean, Septimiu E; Rohling, Robert

    2011-04-01

    To overcome the inherent low frame rate of conventional ultrasound, we have previously presented a system that can be implemented on conventional ultrasound scanners for high-frame-rate imaging of monochromatic tissue motion. The system employs a sector subdivision technique in the sequencer to increase the acquisition rate. To eliminate the delays introduced during data acquisition, a motion phase correction algorithm has also been introduced to create in-phase displacement images. Previous experimental results from tissue- mimicking phantoms showed that the system can achieve effective frame rates of up to a few kilohertz on conventional ultrasound systems. In this short communication, we present a new pulse sequencing strategy that facilitates high-frame-rate imaging of monochromatic motion such that the acquired echo signals are inherently in-phase. The sequencer uses the knowledge of the excitation frequency to synchronize the acquisition of the entire imaging plane to that of an external exciter. This sequencing approach eliminates any need for synchronization or phase correction and has applications in tissue elastography, which we demonstrate with tissue-mimicking phantoms.

  14. Control of cell interaction using quasi-monochromatic light with varying spatiotemporal coherence

    Science.gov (United States)

    Budagovsky, A. V.; Maslova, M. V.; Budagovskaya, O. N.; Budagovsky, I. A.

    2017-02-01

    By the example of plants, fungi and bacteria, we consider the possibility of controlling the interaction of cells, being in competitive, antagonistic, or parasitic relations. For this aim we used short-time irradiation (a few seconds or minutes) with the red (633 nm) quasi-monochromatic light having different spatiotemporal coherence. It is shown that the functional activity is mostly increased in the cells whose size does not exceed the coherence length and the correlation radius of the light field. Thus, in the case of cells essentially differing in size, it is possible to increase the activity of smaller cells, avoiding the stimulation of larger ones. For example, the radiation having relatively low coherence (Lcoh, rcor plant cells by pathogen fungi, while the exposure to light with less statistical regularity (Lcoh = 4 μm, rcor = 5 μm) inhibits the growth of the Fusarium microcera fungus, infected by the bacterium of the Pseudomonas species. The quasi-monochromatic radiation with sufficiently high spatiotemporal coherence stimulated all interacting species (bacteria, fungi, plants). In the considered biocenosis, the equilibrium was shifted towards the favour of organisms having the highest rate of cell division or the ones better using their adaptation potential.

  15. Rod and Rod-driven Function in Achromatopsia and Blue Cone Monochromatism

    Science.gov (United States)

    Moskowitz, Anne; Hansen, Ronald M.; Akula, James D.; Eklund, Susan E.; Fulton, Anne B.

    2008-01-01

    Purpose To evaluate rod photoreceptor and postreceptor retinal function in pediatric patients with achromatopsia (ACHR) and blue cone monochromatism (BCM) using contemporary electroretinographic (ERG) procedures. Methods Fifteen patients (age 1 to 20 years) with ACHR and six patients (age 4 to 22 years) with BCM were studied. ERG responses to full-field stimuli were obtained in scotopic and photopic conditions. Rod photoreceptor (Srod, Rrod) and rod-driven postreceptor (log σ, Vmax) response parameters were calculated from the a-wave and b-wave. The ERG records were digitally filtered to demonstrate the oscillatory potentials (OPs); a sensitivity parameter, log SOPA1/2, and an amplitude parameter, SOPAmax, were used to characterize the OP response. Response parameters were compared to those of 12 normal control subjects. Results As expected, photopic responses were non-detectable in patients with ACHR and BCM. In addition, mean scotopic photoreceptor (Rrod) and postreceptor (Vmax and SOPAmax) amplitude parameters were significantly reduced compared to those in normal controls. The flash intensity required to evoke a half maximum b-wave amplitude (log σ) was significantly increased. Conclusions The results of this study provide evidence that deficits in rod and rod mediated function occur in the primary cone dysfunction syndromes, achromatopsia and blue cone monochromatism. PMID:18824728

  16. Monochromatic light-emitting diode (LED source in layers hens during the second production cycle

    Directory of Open Access Journals (Sweden)

    Rodrigo Borille

    2015-09-01

    Full Text Available ABSTRACTLight is an important environmental factor for birds, allowing not only their vision, but also influencing their physiological responses, such as behavioral and reproductive activity. The objective of this experiment was to evaluate the impact of different colors of monochromatic light (LED sources in laying hens production during the second laying cycle. The study was conducted in an experimental laying house during 70 days. A total of 300 laying hens Isa Brown® genetic strain, aged 95 weeks, in the second laying cycle were used in the study. The artificial light sources used were blue, yellow, green, red and white. The light regimen was continuous illumination of 17 h per day (12 h natural and 5 h artificial in a daily light regimen of 17L:5D (light: dark. The Latin Square design was adopted with five treatments (five colors divided into five periods, and five boxes, with six replicates of ten birds in each box. The production and egg quality were evaluated. The different colors of light source did not affect production parameters or egg quality (p > 0.05. The monochromatic light source may be considered as an alternative to artificial lighting in laying hens during the second production cycle.

  17. Effects of monochromatic light on quality properties and antioxidation of meat in broilers.

    Science.gov (United States)

    Ke, Y Y; Liu, W J; Wang, Z X; Chen, Y X

    2011-11-01

    Our previous study demonstrated that blue monochromatic light was better to promote the growth and development of broilers than red light. However, consumer research suggests that the eating quality of the meat is more important. The present study was, therefore, designed to further evaluate the effects of various monochromatic lights on the muscle growth and quality properties and antioxidation of meat. A total of 288 newly hatched Arbor Acre male broilers were exposed to blue light (BL), green light (GL), red light (RL), and white light (WL) by a light-emitting diode system for 49 d, respectively. Results showed that the broilers reared under BL significantly increased BW and carcass yield as compared with RL, WL, and GL (P 0.05). Compared with RL, the muscles of breast and thigh in GL and BL had higher pH, water-holding capacity, and protein content, whereas cooking loss, lightness value, shear value, and fat content were lower (P 0.05). These results suggest that BL better improves meat quality of Arbor Acre broilers by elevating antioxidative capacity than does RL.

  18. Effect of Stable Magnetic Field on the Phase Transformation of Sr3 Steel

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-an; LIAO Dai-qiang; WU Zhan-jun

    2004-01-01

    The experimental equipment designed by the author was used to carry out quenching treatments on Sr3 steel,with and without magnet it field in different quenching mediums. The effect of steady magnetic field on the phase transformation of Sr3 steel was studied by metallographic microscope and scanning electron microscope. The result shows: the application of magnetic field can obviously increase the volume fraction of ferrite during the austenite to ferrite transformation of Sr3 steel, promote the ferrite grains refining and homogenization, and get the pearlite beam much homogeneously and much compact, when Sr3 steel is quenched in the water.

  19. Skin Treatment with Pulsed Monochromatic UVA1 355 Device and Computerized Morphometric Analysis of Histochemically Identified Langerhans Cells

    Directory of Open Access Journals (Sweden)

    Nicola Zerbinati

    2016-01-01

    Full Text Available Fluorescent or metal halide lamps are widely used in therapeutic applications in dermatological diseases, with broadband or narrow band emission UVA/UVA1 (320–400 nm obtained with suitable passive filters. Recently, it has been possible for us to use a new machine provided with solid state source emitting pulsed monochromatic UVA1 355 nm. In order to evaluate the effects of this emission on immunocells of the skin, human skin samples were irradiated with monochromatic 355 nm UVA1 with different energetic fluences and after irradiation Langerhans cells were labeled with CD1a antibodies. The immunohistochemical identification of these cells permitted evaluating their modifications in terms of density into the skin. Obtained results are promising for therapeutical applications, also considering that a monochromatic radiation minimizes thermic load and DNA damage in the skin tissues.

  20. Co-doping of Ag into Mn:ZnSe Quantum Dots: Giving Optical Filtering effect with Improved Monochromaticity

    OpenAIRE

    Zhiyang Hu; Shuhong Xu; Xiaojing Xu; Zhaochong Wang; Zhuyuan Wang; Chunlei Wang; Yiping Cui

    2015-01-01

    In optics, when polychromatic light is filtered by an optical filter, the monochromaticity of the light can be improved. In this work, we reported that Ag dopant atoms could be used as an optical filter for nanosized Mn:ZnSe quantum dots (QDs). If no Ag doping, aqueous Mn:ZnSe QDs have low monochromaticity due to coexisting of strong ZnSe band gap emission, ZnSe trap emission, and Mn dopant emission. After doping of Ag into QDs, ZnSe band gap and ZnSe trap emissions can be filtered, leaving o...

  1. Selective growth of epitaxial Sr2IrO4 by controlling plume dimensions in pulsed laser deposition

    Science.gov (United States)

    Seo, S. S. A.; Nichols, J.; Hwang, J.; Terzic, J.; Gruenewald, J. H.; Souri, M.; Thompson, J.; Connell, J. G.; Cao, G.

    2016-11-01

    We report that epitaxial Sr2IrO4 thin-films can be selectively grown using pulsed laser deposition (PLD). Due to the competition between the Ruddlesden-Popper phases of strontium iridates (Srn+1IrnO3n+1), conventional PLD methods often result in mixed phases of Sr2IrO4 (n = 1), Sr3Ir2O7 (n = 2), and SrIrO3 (n = ∞). We have discovered that reduced PLD plume dimensions and slow deposition rates are the key for stabilizing pure Sr2IrO4 phase thin-films, identified by real-time in-situ monitoring of their optical spectra. The slow film deposition results in a thermodynamically stable TiO2SrO IrO2SrO SrO configuration at an interface rather than TiO2SrO SrO IrO2SrO between a TiO2-terminated SrTiO3 substrate and a Sr2IrO4 thin film, which is consistent with other layered oxides grown by molecular beam epitaxy. Our approach provides an effective method for using PLD to achieve pure phase thin-films of layered materials that are susceptible to several energetically competing phases.

  2. Some aspects of SR beamline alignment

    Energy Technology Data Exchange (ETDEWEB)

    Gaponov, Yu.A., E-mail: Yury.Gaponov@maxlab.lu.se [MAX-lab, Lund University, P.O.B. 118, SE-221 00 Lund (Sweden); Cerenius, Y. [MAX-lab, Lund University, P.O.B. 118, SE-221 00 Lund (Sweden); Nygaard, J. [Faculty of Life Sciences, University of Copenhagen, DK-1871 Frederiksberg C (Denmark); Ursby, T.; Larsson, K. [MAX-lab, Lund University, P.O.B. 118, SE-221 00 Lund (Sweden)

    2011-09-01

    Based on the Synchrotron Radiation (SR) beamline optical element-by-element alignment with analysis of the alignment results an optimized beamline alignment algorithm has been designed and developed. The alignment procedures have been designed and developed for the MAX-lab I911-4 fixed energy beamline. It has been shown that the intermediate information received during the monochromator alignment stage can be used for the correction of both monochromator and mirror without the next stages of alignment of mirror, slits, sample holder, etc. Such an optimization of the beamline alignment procedures decreases the time necessary for the alignment and becomes useful and helpful in the case of any instability of the beamline optical elements, storage ring electron orbit or the wiggler insertion device, which could result in the instability of angular and positional parameters of the SR beam. A general purpose software package for manual, semi-automatic and automatic SR beamline alignment has been designed and developed using the developed algorithm. The TANGO control system is used as the middle-ware between the stand-alone beamline control applications BLTools, BPMonitor and the beamline equipment.

  3. TU-EF-204-12: Quantitative Evaluation of Spectral Detector CT Using Virtual Monochromatic Images: Initial Results

    Energy Technology Data Exchange (ETDEWEB)

    Duan, X; Guild, J [UT Southwestern Medical Center, Dallas, TX (United States); Arbique, G; Anderson, J [UT Southwestern Medical Ctr at Dallas, Dallas, TX (United States); Dhanantwari, A [Philips Healthcare, Highland Heights, OH (United States); Yagil, Y [Philips Medical Systems, Haifa (Israel)

    2015-06-15

    Purpose To evaluate the image quality and spectral information of a spectral detector CT (SDCT) scanner using virtual monochromatic (VM) energy images. Methods The SDCT scanner (Philips Healthcare) was equipped with a dual-layer detector and spectral iterative reconstruction (IR), which generates conventional 80–140 kV polychromatic energy (PE) CT images using both detector layers, PE images from the low-energy (upper) and high-energy (lower) detector layers and VM images. A solid water phantom with iodine (2.0–20.0 mg I/ml) and calcium (50.0–600.0 mg Ca/ml) rod inserts was used to evaluate effective energy estimate (EEE) and iodine contrast to noise ratio (CNR). The EEE corresponding to an insert CT number in a PE image was calculated from a CT number fit to the VM image set. Since PE image is prone to beam-hardening artifact EEE may underestimate the actual energy separation from two layers of the detector. A 30-cm-diameter water phantom was used to evaluate noise power spectrum (NPS). The phantoms were scanned at 120 and 140 kV with the same CTDIvol. Results The CT number difference for contrast inserts in VM images (50–150 keV) was 1.3±6% between 120 and 140 kV scans. The difference of EEE calculated from low- and high-energy detector images was 11.5 and 16.7 keV for 120 and 140 kV scans, respectively. The differences calculated from 140 and 100 kV conventional PE images were 12.8, and 20.1 keV from 140 and 80 kV conventional PE images. The iodine CNR increased monotonically with decreased keV. Compared to conventional PE images, the peak of NPS curves from VM images were shifted to lower frequency. Conclusion The EEE results indicates that SDCT at 120 and 140 kV may have energy separation comparable to 100/140 kV and 80/140 kV dual-kV imaging. The effects of IR on CNR and NPS require further investigation for SDCT. Author YY and AD are Philips Healthcare employees.

  4. A trapped atom interferometer with ultracold Sr atoms

    CERN Document Server

    Zhang, Xian; Mazzoni, Tommaso; Poli, Nicola; Tino, Guglielmo M

    2016-01-01

    We report on a trapped atom interferometer based on Bragg diffraction and Bloch oscillations with alkaline-earth-metal atoms. We use a Ramsey-Bord\\'e Bragg interferometer with $^{88}$Sr atoms combined with Bloch oscillations to extend the interferometer time. Thanks to a long coherence time for Bloch oscillations of $^{88}$Sr atoms, we observed interference up to 1 s evolution time in the lattice. A detailed study of decoherence sources during the Bloch phase is also presented. While still limited in sensitivity by lattice lifetime and beam inhomogeneity this result opens the way to high contrast trapped interferometers with extended interrogation time.

  5. Computational study of nonlinear plasma waves: 1: Simulation model and monochromatic wave propagation

    Science.gov (United States)

    Matda, Y.; Crawford, F. W.

    1974-01-01

    An economical low noise plasma simulation model is applied to a series of problems associated with electrostatic wave propagation in a one-dimensional, collisionless, Maxwellian plasma, in the absence of magnetic field. The model is described and tested, first in the absence of an applied signal, and then with a small amplitude perturbation, to establish the low noise features and to verify the theoretical linear dispersion relation at wave energy levels as low as 0.000,001 of the plasma thermal energy. The method is then used to study propagation of an essentially monochromatic plane wave. Results on amplitude oscillation and nonlinear frequency shift are compared with available theories. The additional phenomena of sideband instability and satellite growth, stimulated by large amplitude wave propagation and the resulting particle trapping, are described.

  6. A Photodegradation Study of Three Common Paint and Plaster Biocides under monochromatic UV Light

    DEFF Research Database (Denmark)

    Minelgaite, Greta; Vollertsen, Jes; Nielsen, Asbjørn Haaning

    2014-01-01

    Photodegradation of the three common paint-and-plaster biocides (carbendazim, diuron and terbutryn) was investigated at controlled laboratory conditions. Samples prepared in two types of water (demineralized water and pond water) were subjected to 254 nm monochromatic UV light. Light intensity (W m......-2) in the experimental chamber was measured by a fiber optic spectrometer. The observed decline in biocide concentration was related with the light energy, accumulated during the time of degradation (kJ m-2), and 1st order photodegradation rate constants (m2 kJ-1) were determined. The obtained...... results demonstrated that diuron and terbutryn were readily degradable at the tested conditions, while carbendazim remained stable throughout the 28 – 34 hours of the experiments. Photodegradation rate constants of diuron and terbutryn were found to be slightly higher in demineralized water (0.0183 – 0...

  7. Monochromatic radiography of high energy density physics experiments on the MAGPIE generator.

    Science.gov (United States)

    Hall, G N; Burdiak, G C; Suttle, L; Stuart, N H; Swadling, G F; Lebedev, S V; Smith, R A; Patankar, S; Suzuki-Vidal, F; de Grouchy, P; Harvey-Thompson, A J; Bennett, M; Bland, S N; Pickworth, L; Skidmore, J

    2014-11-01

    A monochromatic X-ray backlighter based on Bragg reflection from a spherically bent quartz crystal has been developed for the MAGPIE pulsed power generator at Imperial College (1.4 MA, 240 ns) [I. H. Mitchell et al., Rev. Sci. Instrum. 67, 1533 (2005)]. This instrument has been used to diagnose high energy density physics experiments with 1.865 keV radiation (Silicon He-α) from a laser plasma source driven by a ∼7 J, 1 ns pulse from the Cerberus laser. The design of the diagnostic, its characterisation and performance, and initial results in which the instrument was used to radiograph a shock physics experiment on MAGPIE are discussed.

  8. X-ray Absorption Imaging of High-Intensity Discharge Lamps Using Monochromatic Synchrotron Radiation

    Science.gov (United States)

    Curry, John J.; Sansonetti, Craig J.; Hechtfischer, Ulrich; Adler, Helmar G.

    2002-10-01

    We will report results from the imaging of Hg vapor in high-intensity discharge lamps using synchrotron radiation and digital detectors. These measurements extend previous work on x-ray absorption imaging in arc lamps using an x-ray tube and a passive phosphor image plate detector^i. The large x-ray flux obtained from the Advanced Photon Source (Argonne National Laboratory) combined with the electronic gating capabilities of an intensified charge-coupled device detector have allowed us to obtain time-resolved Hg distributions with high spatial resolution. Monochromatic synchrotron radiation improves the accuracy over what can be obtained with quasi-continuum radiation from an x-ray tube source. ^iJ. J. Curry, M. Sakai, and J. E. Lawler, Journal of Applied Physics 84, 3066 (1998).

  9. A compact design for monochromatic OSL measurements in the wavelength range 380-1020 nm

    Energy Technology Data Exchange (ETDEWEB)

    Boetter-Jensen, L.; Poolton, N.R.J.; Willumsen, F.; Christiansen, H. [Risoe National Lab., Roskilde (Denmark)

    1994-04-01

    The development and performance of a compact module is described that allows for the monochromatic illumination of samples in the wavelength range 380-1020 nm, enabling the measurement of energy-resolved optically stimulated luminescence. The unit is designed to couple directly to the existing automated Risoe TL/OSL dating apparatus, thus allowing for either routine scanning or more detailed thermo-optical investigations. The high throughput efficiency of the unit means that the existing 75 W tungsten-halogen lamp can be directly used for such measurements on both quartz and feldspar samples. The design allows for rapid spectral scanning with a choice of resolution of anywhere between 10 and 80 nm: stray light levels are less than 0.01%. The unit can equally be used for recording wavelength-resolved emission spectra, whether photo-excited or thermally stimulated; the capabilities of the system are demonstrated in the article. (author).

  10. Monochromatic radiography of high energy density physics experiments on the MAGPIE generator

    Energy Technology Data Exchange (ETDEWEB)

    Hall, G. N., E-mail: gareth.hall@imperial.ac.uk; Burdiak, G. C.; Suttle, L.; Stuart, N. H.; Swadling, G. F.; Lebedev, S. V.; Smith, R. A.; Patankar, S.; Suzuki-Vidal, F.; Grouchy, P. de; Harvey-Thompson, A. J.; Bennett, M.; Bland, S. N.; Pickworth, L.; Skidmore, J. [The Blackett Laboratory, Imperial College, London SW7 2BW (United Kingdom)

    2014-11-15

    A monochromatic X-ray backlighter based on Bragg reflection from a spherically bent quartz crystal has been developed for the MAGPIE pulsed power generator at Imperial College (1.4 MA, 240 ns) [I. H. Mitchell et al., Rev. Sci. Instrum. 67, 1533 (2005)]. This instrument has been used to diagnose high energy density physics experiments with 1.865 keV radiation (Silicon He-α) from a laser plasma source driven by a ∼7 J, 1 ns pulse from the Cerberus laser. The design of the diagnostic, its characterisation and performance, and initial results in which the instrument was used to radiograph a shock physics experiment on MAGPIE are discussed.

  11. Parametric decay of a parallel propagating monochromatic whistler wave: Particle-in-cell simulations

    Science.gov (United States)

    Ke, Yangguang; Gao, Xinliang; Lu, Quanming; Wang, Shui

    2017-01-01

    In this paper, by using one-dimensional (1-D) particle-in-cell simulations, we investigate the parametric decay of a parallel propagating monochromatic whistler wave with various wave frequencies and amplitudes. The pump whistler wave can decay into a backscattered daughter whistler wave and an ion acoustic wave, and the decay instability grows more rapidly with the increase of the frequency or amplitude. When the frequency or amplitude is sufficiently large, a multiple decay process may occur, where the daughter whistler wave undergoes a secondary decay into an ion acoustic wave and a forward propagating whistler wave. We also find that during the parametric decay a considerable part of protons can be accelerated along the background magnetic field by the enhanced ion acoustic wave through the Landau resonance. The implication of the parametric decay to the evolution of whistler waves in Earth's magnetosphere is also discussed in the paper.

  12. JAEA-ASRC μSR project at J-PARC MUSE

    Science.gov (United States)

    Higemoto, W.; Heffner, R. H.; Shimomura, K.; Nishiyama, K.; Miyake, Y.

    2009-02-01

    The Japan Atomic Energy Agency (JAEA)-Advanced Science Research Center (ASRC) is advancing a "μSR project" at the J-PARC MLF muon science facility (MUSE). This project entails extracting part of the muon beam into a muon spectrometer constructed downstream from the Decay/Surface muon beam line. One of the main subjects of study at the ASRC μSR project will be an examination of strongly correlated electron systems, especially f-electron systems. The intense muon beams available at MUSE will yield new insights for f-electron physics.

  13. Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO{sub 3}){sub n} films by means of metalorganic aerosol deposition

    Energy Technology Data Exchange (ETDEWEB)

    Jungbauer, M.; Hühn, S.; Moshnyaga, V. [Erstes Physikalisches Institut, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G. [EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

    2014-12-22

    We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO{sub 3}){sub n} (n = ∞, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO{sub 3}(001) substrates by means of a sequential deposition of Sr-O/Ti-O{sub 2} atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2–4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5–6 repetitions of the SrO(SrTiO{sub 3}){sub 4} block at the level of 2.4%. This identifies the SrTiO{sub 3} substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy.

  14. Intrinsic spontaneous emission-induced fluctuations of the output optical beam power and phase in a diode amplifier

    Science.gov (United States)

    Bogatov, A. P.; Drakin, A. E.; D'yachkov, N. V.; Gushchik, T. I.

    2016-08-01

    Output optical beam intensity and phase fluctuations are analysed in a classical approach to describing the propagation and amplification of spontaneous emission in the active region of a laser diode with a gain saturated by input monochromatic light. We find their spectral densities and dispersion and the correlation coefficient of the two-dimensional probability distribution function of the fluctuations.

  15. 87Sr/86Sr sourcing of ponderosa pine used in Anasazi great house construction at Chaco Canyon, New Mexico

    Science.gov (United States)

    Reynolds, Amanda C.; Betancourt, Julio L.; Quade, Jay; Patchett, P. Jonathan; Dean, Jeffery S.; Stein, John

    2005-01-01

    Previous analysis of 87Sr/86Sr ratios shows that 10th through 12th century Chaco Canyon was provisioned with plant materials that came from more than 75 km away. This includes (1) corn (Zea mays) grown on the eastern flanks of the Chuska Mountains and floodplain of the San Juan River to the west and north, and (2) spruce (Picea sp.) and fir (Abies sp.) beams from the crest of the Chuska and San Mateo Mountains to the west and south. Here, we extend 87Sr/86Sr analysis to ponderosa pine (Pinus ponderosa) prevalent in the architectural timber at three of the Chacoan great houses (Pueblo Bonito, Chetro Ketl, Pueblo del Arroyo). Like the architectural spruce and fir, much of the ponderosa matches the 87Sr/86Sr ratios of living trees in the Chuska Mountains. Many of the architectural ponderosa, however, have similar ratios to living trees in the La Plata and San Juan Mountains to the north and Lobo Mesa/Hosta Butte to the south. There are no systematic patterns in spruce/fir or ponderosa provenance by great house or time, suggesting the use of stockpiles from a few preferred sources. The multiple and distant sources for food and timber, now based on hundreds of isotopic values from modern and archeological samples, confirm conventional wisdom about the geographic scope of the larger Chacoan system. The complexity of this procurement warns against simple generalizations based on just one species, a single class of botanical artifact, or a few isotopic values.

  16. Virtual monochromatic imaging in dual-source and dual-energy CT for visualization of acute ischemic stroke

    CERN Document Server

    Hara, Hidetake; Matsuzawa, Hiroki; Inoue, Toshiyuki; Abe, Shinji; Satoh, Hitoshi; Nakajima, Yasuo

    2015-01-01

    We have recently developed a phantom that simulates acute ischemic stroke. We attempted to visualize acute-stage cerebral infarction by applying virtual monochromatic images to this phantom using dual-energy CT (DECT). Virtual monochromatic images were created using DECT from 40 to 100 keV at every 10 keV and from 60 to 80 keV at every 1 keV, under three energy conditions of tube voltages with thin (Sn) filters. Calculation of the CNR values allowed us to evaluate the visualization of acute-stage cerebral infarction. The CNR value of a virtual monochromatic image was the highest at 68 keV under 80 kV / Sn 140 kV, at 72 keV under 100 kV / Sn 140 kV, and at 67 keV under 140 kV / 80 kV. The CNR values of virtual monochromatic images between 65 and 75 keV were significantly higher than those obtained for all other created energy images. Therefore, optimal conditions for visualizing acute ischemic stroke were achievable.

  17. Electron Spin Resonance of Single Crystals of Cystine Dihydrochloride Irradiated with Monochromatic UV Radiation at Various Wavelenghts

    DEFF Research Database (Denmark)

    Lund-Thomsen, E.; Nielsen, S. O.

    1972-01-01

    Single crystals of cystine dihydrochloride were irradiated at room temperature with monochromatic uv radiation. The optical bandwidth was about 20 Å for each wavelength used. Essentially two ESR centers were observed, the relative yield being approximately 1. One center is identified as the RS...

  18. Virtual monochromatic imaging in dual-source and dual-energy CT for visualization of acute ischemic stroke

    Science.gov (United States)

    Hara, Hidetake; Muraishi, Hiroshi; Matsuzawa, Hiroki; Inoue, Toshiyuki; Nakajima, Yasuo; Satoh, Hitoshi; Abe, Shinji

    2015-07-01

    We have recently developed a phantom that simulates acute ischemic stroke. We attempted to visualize an acute-stage cerebral infarction by using dual-energy Computed tomography (DECT) to obtain virtual monochromatic images of this phantom. Virtual monochromatic images were created by using DECT voltages from 40 to 100 keV in steps of 10 keV and from 60 to 80 keV in steps of 1 keV, under three conditions of the tube voltage with thin (Sn) filters. Calculation of the CNR values allowed us to evaluate the visualization of acute-stage cerebral infarction. The CNR value of a virtual monochromatic image was the highest at 68 keV under 80 kV / Sn 140 kV, at 72 keV under 100 kV / Sn 140 kV, and at 67 keV under 140 kV / 80 kV. The CNR values of virtual monochromatic images at voltages between 65 and 75 keV were significantly higher than those obtained for all other created images. Therefore, the optimal conditions for visualizing acute ischemic stroke were achievable.

  19. Modulation depth of Michelson interferometer with Gaussian beam.

    Science.gov (United States)

    Välikylä, Tuomas; Kauppinen, Jyrki

    2011-12-20

    Mirror misalignment or the tilt angle of the Michelson interferometer can be estimated from the modulation depth measured with collimated monochromatic light. The intensity of the light beam is usually assumed to be uniform, but, for example, with gas lasers it generally has a Gaussian distribution, which makes the modulation depth less sensitive to the tilt angle. With this assumption, the tilt angle may be underestimated by about 50%. We have derived a mathematical model for modulation depth with a circular aperture and Gaussian beam. The model reduces the error of the tilt angle estimate to below 1%. The results of the model have been verified experimentally.

  20. Two-color beam generation based on wakefield excitation

    Science.gov (United States)

    Bettoni, S.; Prat, E.; Reiche, S.

    2016-05-01

    Several beam manipulation methods have been studied and experimentally tested to generate two-color photon beams in free electron laser facilities to accommodate the user requests. We propose to use the interaction of the beam with an oscillating longitudinal wakefield source to obtain a suitable electron beam structure. The bunch generates two subpulses with different energies and delayed in time passing through a magnetic chicane after its longitudinal phase space has been modulated by the wakefield source. According to this approach the power of the emitted radiation is not degraded compared to the monochromatic beam, and the setup in the machine is quite simple because the bunch is manipulated only in the high energy section, where it is more rigid. We present the design applied to SwissFEL. We identified the parameters and the corresponding range of tunability of the time and energy separation among the two subbunches.

  1. Slow electrostatic fluctuations generated by beam-plasma interaction

    CERN Document Server

    Pommois, Karen; Pezzi, Oreste; Veltri, Pierluigi

    2016-01-01

    Eulerian simulations of the Vlasov-Poisson equations have been employed to analyze the excitation of slow electrostatic fluctuations (with phase speed close to the electron thermal speed), due to a beam-plasma interaction, and their propagation in linear and nonlinear regime. In 1968, O'Neil and Malmberg [Phys. Fluids {\\bf 11}, 1754 (1968)] dubbed these waves "beam modes". In the present paper, it is shown that, in the presence of a cold and low density electron beam, these beam modes can become unstable and then survive Landau damping unlike the Langmuir waves. When an electron beam is launched in a plasma of Maxwellian electrons and motionless protons and this initial equilibrium is perturbed by a monochromatic density disturbance, the electric field amplitude grows exponentially in time and then undergoes nonlinear saturation, associated with the kinetic effects of particle trapping and phase space vortex generation. Moreover, if the initial density perturbation is setup in the form of a low amplitude rand...

  2. Spectral responsivity calibration of the reference radiation thermometer at KRISS by using a super-continuum laser-based high-accuracy monochromatic source

    Science.gov (United States)

    Yoo, Yong Shim; Kim, Gun Jung; Park, Seongchong; Lee, Dong-Hoon; Kim, Bong-Hak

    2016-12-01

    We report on the calibration of the relative spectral responsivity of the reference radiation thermometer, model LP4, which is used for the experimental realisation of the international temperature scale of 1990 above 960 °C at the Korea Research Institute of Standards and Science. The relative spectral responsivity of LP4 is measured by using a monochromatic source consisting of a super-continuum laser and a double-grating monochromator. By monitoring the wavelength of the output beam directly with a calibrated wavelength-meter, we achieved a high-accuracy measurement of spectral responsivity with a maximum wavelength error of less than 3 pm, a narrow spectral bandwidth of less than 0.4 nm, and a high dynamic range over 8 decades. We evaluated the contributions of various uncertainty components of the spectral responsivity measurement to the uncertainty of the temperature scale based on a practical estimation approach, which numerically calculates the maximal effects of the variations of each component. As a result, we evaluate the uncertainty contribution from the spectral responsivity measurement to the temperature scale to be less than 64 mK (k  =  1) in a range from 660 °C to 2749 °C for the LP4 with a filter at 650 nm.

  3. Ultrahigh brilliance quasi-monochromatic MeV γ-rays based on self-synchronized all-optical Compton scattering

    Science.gov (United States)

    Yu, Changhai; Qi, Rong; Wang, Wentao; Liu, Jiansheng; Li, Wentao; Wang, Cheng; Zhang, Zhijun; Liu, Jiaqi; Qin, Zhiyong; Fang, Ming; Feng, Ke; Wu, Ying; Tian, Ye; Xu, Yi; Wu, Fenxiang; Leng, Yuxin; Weng, Xiufeng; Wang, Jihu; Wei, Fuli; Yi, Yicheng; Song, Zhaohui; Li, Ruxin; Xu, Zhizhan

    2016-07-01

    Inverse Compton scattering between ultra-relativistic electrons and an intense laser field has been proposed as a major route to generate compact high-brightness and high-energy γ-rays. Attributed to the inherent synchronization mechanism, an all-optical Compton scattering γ-ray source, using one laser to both accelerate electrons and scatter via the reflection of a plasma mirror, has been demonstrated in proof-of-principle experiments to produce a x-ray source near 100 keV. Here, by designing a cascaded laser wakefield accelerator to generate high-quality monoenergetic e-beams, which are bound to head-on collide with the intense driving laser pulse via the reflection of a 20-um-thick Ti foil, we produce tunable quasi-monochromatic MeV γ-rays (33% full-width at half-maximum) with a peak brilliance of ~3 × 1022 photons s-1 mm-2 mrad-2 0.1% BW at 1 MeV. To the best of our knowledge, it is one order of magnitude higher than ever reported value of its kinds in MeV regime. This compact ultrahigh brilliance γ-ray source may provide applications in nuclear resonance fluorescence, x-ray radiology and ultrafast pump-probe nondestructive inspection.

  4. Compton scattering monochromatic X-ray source based on X-band multi-bunch linac at the University of Tokyo

    Science.gov (United States)

    Sakamoto, F.; Uesaka, M.; Taniguchi, Y.; Natsui, T.; Hashimoto, E.; Woo, L. K.; Yamamoto, T.; Urakawa, J.; Yoshida, M.; Higo, T.; Fukuda, S.; Kaneko, N.; Nose, H.; Sakae, H.; Nakamura, N.; Yamamoto, M.

    2009-09-01

    We are currently developing a compact monochromatic X-ray source based on laser-electron Compton scattering for the purpose of medical applications at the University of Tokyo. To realize remarkably compact-, high-intensity- and highly stable system, we adopt an X-band (11.424 GHz) multi-bunch linear accelerator (linac) and reliable Q-switch Nd:YAG laser. The injector of the system consists of a 3.5-cell X-band thermionic cathode RF-gun and an alpha magnet. So far, we have continued high-power experiment and beam generation on X-band thermionic cathode RF-gun. However, breakdown was frequently occurred at coaxial structure around the thermionic cathode. In order to resolve the breakdown, we adopt a choke structure around the thermionic cathode. In this paper, the details of Compton scattering X-ray source the University of Tokyo, the experimental results of the X-ray generation, and upgrade of the X-band thermionic cathode RF-gun will be presented.

  5. Abdominal CT: An intra-individual comparison between virtual monochromatic spectral and polychromatic 120-kVp images obtained during the same examination

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Yoshitake, E-mail: yamada@rad.med.keio.ac.jp [Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Jinzaki, Masahiro, E-mail: jinzaki@rad.med.keio.ac.jp [Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Hosokawa, Takahiro, E-mail: snowglobe@infoseek.jp [Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Tanami, Yutaka, E-mail: tanami@rad.med.keio.ac.jp [Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Abe, Takayuki, E-mail: tabe@z5.keio.jp [Center for Clinical Research, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Kuribayashi, Sachio, E-mail: skuribay@med.keio.ac.jp [Department of Diagnostic Radiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan)

    2014-10-15

    Highlights: • We compared virtual monochromatic spectral (VMS) images with 120-kVp images. • VMS images are generated using accurate two-material beam-hardening correction. • Abdominal 70-keV VMS images provide better image quality than 120-kVp images. • Iterative reconstruction can further improve the image quality of VMS images. - Abstract: Objectives: To compare quantitative and subjective image quality between virtual monochromatic spectral (VMS) and conventional polychromatic 120-kVp imaging performed during the same abdominal computed tomography (CT) examination. Materials and methods: Our institutional review board approved this prospective study; each participant provided written informed consent. 51 patients underwent sequential fast kVp-switching dual-energy (80/140 kVp, volume CT dose index: 12.7 mGy) and single-energy (120-kVp, 12.7 mGy) abdominal enhanced CT over an 8 cm scan length with a random acquisition order and a 4.3-s interval. VMS images with filtered back projection (VMS-FBP) and adaptive statistical iterative reconstruction (so-called hybrid IR) (VMS-ASIR) (at 70 keV), as well as 120-kVp images with FBP (120-kVp-FBP) and ASIR (120-kVp-ASIR), were generated from dual-energy and single-energy CT data, respectively. The objective image noises, signal-to-noise ratios and contrast-to-noise ratios of the liver, kidney, pancreas, spleen, portal vein and aorta, and the lesion-to-liver and lesion-to-kidney contrast-to-noise ratios were measured. Two radiologists independently and blindly assessed the subjective image quality. The results were analyzed using the paired t-test, Wilcoxon signed rank sum test and mixed-effects model with Bonferroni correction. Results: VMS-ASIR images were superior to 120-kVp-FBP, 120-kVp-ASIR and VMS-FBP images for all the quantitative assessments and the subjective overall image quality (all P < 0.001), while VMS-FBP images were superior to 120-kVp-FBP and 120-kVp-ASIR images (all P < 0.004). Conclusions: VMS

  6. Spectral properties of Compton inverse radiation: Application of Compton beams

    CERN Document Server

    Bulyak, Eugene

    2013-01-01

    Compton inverse radiation emitted due to backscattering of laser pulses off the relativistic electrons possesses high spectral density and high energy of photons - in hard x-ray up to gamma-ray energies - because of short wavelength of laser radiation as compared with the classical electromagnetic devices such as undulators. In this report, the possibility of such radiation to monochromatization by means of collimation is studied. Two approaches have been considered for the description of the spectral-angular density of Compton radiation based on the classical field theory and on the quantum electrodynamics. As is shown, both descriptions produce similar total spectra. On the contrary, angular distribution of the radiation is different: the classical approach predicted a more narrow radiation cone. Also proposed and estimated is a method of the `electronic' monochromatization based on the electronic subtraction of the two images produced by the electron beams with slightly different energies. A `proof-of-prin...

  7. Quasiperiodic behavior in beam-driven strong Langmuir turbulence

    Science.gov (United States)

    Robinson, P. A.; Newman, D. L.

    1989-01-01

    The evolution of unmagnetized beam-driven strong Langmuir turbulence is studied in two dimensions by numerically integrating the Zakharov equations for systems pumped by monochromatic and broadband negative-damping drivers with nonzero central wavenumber. Long-time statistically steady states are reached for which the dependence of the evolution on the driver wavenumber, growth rate, and bandwidth is examined in detail. For monochromatic drivers, a quasiperiodic cycle is found to develop if the driver wavenumber is sufficiently large. The characteristic frequency of the quasiperiodic cycle and the average system energy are both approximately proportional to the growth rate. Broadening of the driver in wavenumber tends to degrade the system-wide coherence of the cycle, but its main features appear to survive on the scale of the coherence length of the driver.

  8. Optimization of a constrained linear monochromator design for neutral atom beams.

    Science.gov (United States)

    Kaltenbacher, Thomas

    2016-04-01

    A focused ground state, neutral atom beam, exploiting its de Broglie wavelength by means of atom optics, is used for neutral atom microscopy imaging. Employing Fresnel zone plates as a lens for these beams is a well established microscopy technique. To date, even for favorable beam source conditions a minimal focus spot size of slightly below 1μm was reached. This limitation is essentially given by the intrinsic spectral purity of the beam in combination with the chromatic aberration of the diffraction based zone plate. Therefore, it is important to enhance the monochromaticity of the beam, enabling a higher spatial resolution, preferably below 100nm. We propose to increase the monochromaticity of a neutral atom beam by means of a so-called linear monochromator set-up - a Fresnel zone plate in combination with a pinhole aperture - in order to gain more than one order of magnitude in spatial resolution. This configuration is known in X-ray microscopy and has proven to be useful, but has not been applied to neutral atom beams. The main result of this work is optimal design parameters based on models for this linear monochromator set-up followed by a second zone plate for focusing. The optimization was performed for minimizing the focal spot size and maximizing the centre line intensity at the detector position for an atom beam simultaneously. The results presented in this work are for, but not limited to, a neutral helium atom beam.

  9. Effects of monochromatic light on mucosal mechanical and immunological barriers in the small intestine of broilers.

    Science.gov (United States)

    Xie, D; Li, J; Wang, Z X; Cao, J; Li, T T; Chen, J L; Chen, Y X

    2011-12-01

    Our previous studies demonstrated that green and blue monochromatic lights were effective to stimulate immune response of the spleen in broilers. This study was designed to investigate the effects of monochromatic light on both gut mucosal mechanical and immunological barriers. A total of 120 Arbor Acre male broilers on post-hatching day (P) 0 were exposed to red light, green light (GL), blue light (BL), and white light (WL) for 49 d, respectively. As compared with broilers exposed to WL, the broilers exposed to GL showed that the villus height of small intestine was increased by 19.5% (P = 0.0205) and 38.8% (P = 0.0149), the crypt depth of small intestine was decreased by 15.1% (P = 0.0049) and 10.1% (P = 0.0005), and the ratios of villus height to crypt depth were increased by 39.3% (P < 0.0001) and 52.5% (P < 0.0001) at P7 and P21, respectively. Until P49, an increased villus height (33.6%, P = 0.0076), a decreased crypt depth (15.4%, P = 0.0201), and an increased villus height-to-crypt depth ratio (58.5%, P < 0.0001) were observed in the BL group as compared with the WL group. On the other hand, the numbers of intestinal intraepithelial lymphocytes (27.9%, P < 0.0001 and 37.0%, P < 0.0001), goblet cells (GC, 22.1%, P < 0.0001 and 18.1%, P < 0.0001), and IgA(+) cells (14.8%, P = 0.0543 and 47.9%, P = 0.0377) in the small intestine were significantly increased in the GL group as compared with the WL group at P7 and P21, respectively. The numbers of intestinal intraepithelial lymphocytes (36.2%, P < 0.0001), GC (26.5%, P < 0.0001), and IgA(+) cells (68.0%, P = 0.0177) in the BL group were also higher than those in the WL group at P49. These results suggest that both mucosal mechanical and immunological barriers of the small intestine may be improved by rearing broilers under GL at an early age and under BL at an older age.

  10. Photofission of {sup NAT} Pt by monochromatic and polarized photons in the quasi-deuteron region; Fotofissao da {sup NAT} Pt por fotons monocromaticos e polarizados na regiao do quase-deuteron

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Eduardo de

    1992-01-01

    The measurement of the Nat Pt photofission yield at 69 MeV of effective average energy of the incident photon is made using a polarized and monochromatic photon beam from the LADON system of the National Laboratory of Frascati, Italy, produced by inverse Compton scattering of laser light by high energy electrons of the ADONE Accelerator and using as fission track solid detector the Makrofol, being the developing made by usual procedure. The experimental value of the nuclear fissionability is compared to a theoretical value obtained following a model at two stages: in the first, the photon energy is absorbed by a neutron-proton pair inducing to the nucleus excitation, and in the second the nucleus de-excites due to the competition between nucleon evaporation and fission. The effect of fast nucleon emission during the first stage and the successive evaporation of neutrons in the second stage are considered. 40 refs, 12 figs, 9 tabs.

  11. 对数螺旋型劳厄弯晶的X射线单色成像应用%Logarithmic Spiral Bent Laue Crystals for X-Ray Monochromatic Imaging Applications

    Institute of Scientific and Technical Information of China (English)

    毋玉芬; 肖沙里; 鲁建; 钱家渝; 刘利锋; 黄显宾

    2013-01-01

    Taking advantages of the monochromatic X-ray diffraction property of Laue crystals,an innovative use of logarithmic spiral bent Laue crystals for X-ray monochromatic imaging is investigated.According to the ray tracing method and the surface equation of the logarithmic spiral,the imaging principles and characteristics of the logarithmic spiral bent Laue crystals are studied,including the condition that the diffracted beam can be separated from the transmitted beam,the magnifications and the field of view (FOV).A logarithmic spiral bent quartz (1010) Laue crystal analyzer is developed.With the proposed crystal analyzer,the monochromatic backlight imaging experiment for the mesh grid with a diameter of 50 μm is carried out by taking an X-ray source of Cu target as the backlighter.The experimental results show that the spatial resolution of the analyzer is approximately 11.9 μm under a source diameter of 110 μm.Furthermore,the FOVs of the crystal analyzer are 22.3557 mm and 8.2602 mm in horizontal and vertical directions,respectively.%利用劳厄晶体研究了X射线的单色衍射性质,研究了对数螺旋型劳厄弯晶在等离子体X射线单色成像中的应用.根据光线追迹原理及对数螺旋线的表面方程,研究了对数螺旋型劳厄弯晶的单色成像原理,分析了单色衍射像不受透射白光X射线影响的准则,以及子午、弧矢放大倍数和单色成像视场等性能参数.研制了石英晶体(1010)对数螺旋劳厄弯晶分析器,以铜靶X射线源作为背光源,对网丝直径为50 μm的金属网格进行了单色背光成像实验.实验结果表明,当背光源尺寸为110 μm时,对数螺旋型劳厄弯晶的空间分辨力约为11.9μm,分析器在子午和弧矢方向的视场分别达到22.3557 mm和8.2602 mm.

  12. Modulatory Effect of Monochromatic Blue Light on Heat Stress Response in Commercial Broilers

    Science.gov (United States)

    Abdo, Safaa E.; Mahmoud, Shawky

    2017-01-01

    In a novel approach, monochromatic blue light was used to investigate its modulatory effect on heat stress biomarkers in two commercial broiler strains (Ross 308 and Cobb 500). At 21 days old, birds were divided into four groups including one group housed in white light, a second group exposed to blue light, a 3rd group exposed to white light + heat stress, and a 4th group exposed to blue light + heat stress. Heat treatment at 33°C lasted for five h for four successive days. Exposure to blue light during heat stress reduced MDA concentration and enhanced SOD and CAT enzyme activities as well as modulated their gene expression. Blue light also reduced the degenerative changes that occurred in the liver tissue as a result of heat stress. It regulated, though variably, liver HSP70, HSP90, HSF1, and HSF3 gene expression among Ross and Cobb chickens. Moreover, the Cobb strain showed better performance than Ross manifested by a significant reduction of rectal temperature in the case of H + B. Furthermore, a significant linear relationship was found between the lowered rectal temperature and the expression of all HSP genes. Generally, the performance of both strains by most assessed parameters under heat stress is improved when using blue light. PMID:28698764

  13. Experimental and Numerical Studies on Wave Breaking Characteristics over a Fringing Reef under Monochromatic Wave Conditions

    Directory of Open Access Journals (Sweden)

    Jong-In Lee

    2014-01-01

    Full Text Available Fringing reefs play an important role in protecting the coastal area by inducing wave breaking and wave energy dissipation. However, modeling of wave transformation and energy dissipation on this topography is still difficult due to the unique structure. In the present study, two-dimensional laboratory experiments were conducted to investigate the cross-shore variations of wave transformation, setup, and breaking phenomena over an idealized fringing reef with the 1/40 reef slope and to verify the Boussinesq model under monochromatic wave conditions. One-layer and two-layer model configurations of the Boussinesq model were used to figure out the model capability. Both models predicted well (r2>0.8 the cross-shore variation of the wave heights, crests, troughs, and setups when the nonlinearity is not too high (A0/h0<0.07 in this study. However, as the wave nonlinearity and steepness increase, the one-layer model showed problems in prediction and stability due to the error on the vertical profile of fluid velocity. The results in this study revealed that one-layer model is not suitable in the highly nonlinear wave condition over a fringing reef bathymetry. This data set can contribute to the numerical model verification.

  14. Micro-strip metal detector for the beam profile monitoring

    Science.gov (United States)

    Pugatch, V.; Borysova, M.; Mykhailenko, A.; Fedorovitch, O.; Pylypchenko, Y.; Perevertaylo, V.; Franz, H.; Wittenburg, K.; Schmelling, M.; Bauer, C.

    2007-10-01

    The Micro-strip Metal Detector (MMD) design and production technology, readout electronics as well as areas of applications are described. The MMD was designed for beam profile monitoring of charged particle and synchrotron radiation beams. Using photolithography and plasma-chemistry etching technologies we succeeded in creating detectors with a metal strip's thickness of less than 2 μm and without any other materials in the working area. The principle of operation is based on the Secondary Electron Emission (SEE). The results obtained with the MMD at the monochromatic synchrotron radiation beam at HASYLAB (DESY) are also presented. The current version of the MMD allows measuring a beam profile and position with an accuracy of 20 μm.

  15. Micro-strip metal detector for the beam profile monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Pugatch, V.; Borysova, M. [Kyiv Institute for Nuclear Research, Kyiv (Ukraine); Mykhailenko, A. [Kyiv Institute for Nuclear Research, Kyiv (Ukraine)], E-mail: mykhailenko@kinr.kiev.ua; Fedorovitch, O.; Pylypchenko, Y. [Kyiv Institute for Nuclear Research, Kyiv (Ukraine); Perevertaylo, V. [Institute of Micro Devices, Kyiv (Ukraine); Franz, H.; Wittenburg, K. [Deutsches Elektronen-Synchrotron, Hamburg (Germany); Schmelling, M.; Bauer, C. [Max-Planck-Institute for Nuclear Physics, Heidelberg (Germany)

    2007-10-21

    The Micro-strip Metal Detector (MMD) design and production technology, readout electronics as well as areas of applications are described. The MMD was designed for beam profile monitoring of charged particle and synchrotron radiation beams. Using photolithography and plasma-chemistry etching technologies we succeeded in creating detectors with a metal strip's thickness of less than 2{mu}m and without any other materials in the working area. The principle of operation is based on the Secondary Electron Emission (SEE). The results obtained with the MMD at the monochromatic synchrotron radiation beam at HASYLAB (DESY) are also presented. The current version of the MMD allows measuring a beam profile and position with an accuracy of 20{mu}m.

  16. Thermoluminescence dependence on the wavelength of monochromatic UV-radiation in Cu-doped KCl and KBr at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Perez R, A.; Piters, T.; Aceves, R.; Rodriguez M, R.; Perez S, R., E-mail: rperez@cifus.uson.mx [Universidad de Sonora, Departamento de Investigaciones en Fisica, Apdo. Postal 5-088, 83190 Hermosillo, Sonora (Mexico)

    2014-08-15

    Thermoluminescence (Tl) dependence on the UV irradiation wavelengths from 200 to 500 nm in Cu-doped KCl and KBr crystals with different thermal treatment has been analyzed. Spectrum of the Tl intensity of each material show lower intensity at wavelengths longer than 420 nm. The Tl intensity depends on the irradiation wavelength. Structure of the Tl intensity spectrum of each sample is very similar to the structure of its optical absorption spectrum, indicating that at each wavelength, monochromatic radiation is absorbed to produce electronic transitions and electron hole pairs. Thermoluminescence of materials with thermal treatment at high temperature shows electron-hole trapping with less efficiency. The results show that Cu-doped alkali-halide materials are good detectors of a wide range of UV monochromatic radiations and could be used to measure UV radiation doses. (Author)

  17. A phase-space beam position monitor for synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Samadi, Nazanin, E-mail: nazanin.samadi@usask.ca [University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK (Canada); Bassey, Bassey; Martinson, Mercedes [University of Saskatchewan, 116 Science Place, Saskatoon, SK (Canada); Belev, George; Dallin, Les; Jong, Mark de [Canadian Light Source, 44 Innovation Boulevard, Saskatoon, SK (Canada); Chapman, Dean [University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK (Canada)

    2015-06-25

    A system has been developed to measure the vertical position and angle of the electron beam at a single location from a synchrotron source. The system uses a monochromator tuned to the absorption edge of a contrast material and has a sensitivity comparable with other beam position monitors. The stability of the photon beam position on synchrotron beamlines is critical for most if not all synchrotron radiation experiments. The position of the beam at the experiment or optical element location is set by the position and angle of the electron beam source as it traverses the magnetic field of the bend-magnet or insertion device. Thus an ideal photon beam monitor would be able to simultaneously measure the photon beam’s position and angle, and thus infer the electron beam’s position in phase space. X-ray diffraction is commonly used to prepare monochromatic beams on X-ray beamlines usually in the form of a double-crystal monochromator. Diffraction couples the photon wavelength or energy to the incident angle on the lattice planes within the crystal. The beam from such a monochromator will contain a spread of energies due to the vertical divergence of the photon beam from the source. This range of energies can easily cover the absorption edge of a filter element such as iodine at 33.17 keV. A vertical profile measurement of the photon beam footprint with and without the filter can be used to determine the vertical centroid position and angle of the photon beam. In the measurements described here an imaging detector is used to measure these vertical profiles with an iodine filter that horizontally covers part of the monochromatic beam. The goal was to investigate the use of a combined monochromator, filter and detector as a phase-space beam position monitor. The system was tested for sensitivity to position and angle under a number of synchrotron operating conditions, such as normal operations and special operating modes where the photon beam is intentionally altered

  18. Metal artifacts reduction using monochromatic images from spectral CT: Evaluation of pedicle screws in patients with scoliosis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yang, E-mail: wangzhang227@163.com [Department of Radiology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008 (China); Qian, Bangping, E-mail: qianbangping@163.com [Spine Service, Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008 (China); Li, Baoxin, E-mail: wangzhi68@163.com [Department of Radiology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008 (China); Qin, Guochu, E-mail: qgc7605@yahoo.com.cn [Department of Radiology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008 (China); Zhou, Zhengyang, E-mail: zyzhou@nju.edu.cn [Department of Radiology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008 (China); Qiu, Yong, E-mail: scoliosis2002@sina.com [Spine Service, Drum Tower Hospital, Nanjing University Medical School, Nanjing 210008 (China); Sun, Xizhao, E-mail: sunxizhaonj@163.com [Department of Radiology and Urology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, No. 321 Zhongshan Road, Nanjing 210008 (China); Zhu, Bin, E-mail: gobin10266@163.com [Department of Radiology, The Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008 (China)

    2013-08-15

    Purpose: To evaluate the effectiveness of spectral CT in reducing metal artifacts caused by pedicle screws in patients with scoliosis. Materials and methods: Institutional review committee approval and written informed consents from patients were obtained. 18 scoliotic patients with a total of 228 pedicle screws who underwent spectral CT imaging were included in this study. Monochromatic image sets with and without the additional metal artifacts reduction software (MARS) correction were generated with photon energy at 65 keV and from 70 to 140 keV with 10 keV interval using the 80 kVp and 140 kVp projection sets. Polychromatic images corresponded to the conventional 140 kVp imaging were also generated from the same scan data as a control group. Both objective evaluation (screw width and quantitative artifacts index measurements) and subjective evaluation (depiction of pedicle screws, surrounding structures and their relationship) were performed. Results: Image quality of monochromatic images in the range from 110 to 140 keV (0.97 ± 0.28) was rated superior to the conventional polychromatic images (2.53 ± 0.54) and also better than monochromatic images with lower energy. Images of energy above 100 keV also give accurate measurement of the width of screws and relatively low artifacts index. The form of screws was slightly distorted in MARS reconstruction. Conclusions: Compared to conventional polychromatic images, monochromatic images acquired from dual-energy CT provided superior image quality with much reduced metal artifacts of pedicle screws in patients with scoliosis. Optimal energy range was found between 110 and 140 keV.

  19. Co-doping of Ag into Mn:ZnSe Quantum Dots: Giving Optical Filtering effect with Improved Monochromaticity.

    Science.gov (United States)

    Hu, Zhiyang; Xu, Shuhong; Xu, Xiaojing; Wang, Zhaochong; Wang, Zhuyuan; Wang, Chunlei; Cui, Yiping

    2015-10-08

    In optics, when polychromatic light is filtered by an optical filter, the monochromaticity of the light can be improved. In this work, we reported that Ag dopant atoms could be used as an optical filter for nanosized Mn:ZnSe quantum dots (QDs). If no Ag doping, aqueous Mn:ZnSe QDs have low monochromaticity due to coexisting of strong ZnSe band gap emission, ZnSe trap emission, and Mn dopant emission. After doping of Ag into QDs, ZnSe band gap and ZnSe trap emissions can be filtered, leaving only Mn dopant emission with improved monochromaticity. The mechanism for the optical filtering effect of Ag was investigated. The results indicate that the doping of Ag will introduce a new faster deactivation process from ZnSe conduction band to Ag energy level, leading to less electrons deactived via ZnSe band gap emission and ZnSe trap emission. As a result, only Mn dopant emission is left.

  20. Development and Optimisation of the SPS and LHC beam diagnostics based on Synchrotron Radiation monitors

    CERN Document Server

    AUTHOR|(CDS)2081364; Roncarolo, Federico

    Measuring the beam transverse emittance is fundamental in every accelerator, in particular for colliders, where its precise determination is essential to maximize the luminosity and thus the performance of the colliding beams.
 Synchrotron Radiation (SR) is a versatile tool for non-destructive beam diagnostics, since its characteristics are closely related to those of the source beam. At CERN, being the only available diagnostics at high beam intensity and energy, SR monitors are exploited as the proton beam size monitor of the two higher energy machines, the Super Proton Synchrotron (SPS) and the Large Hadron Collider (LHC). The thesis work documented in this report focused on the design, development, characterization and optimization of these beam size monitors. Such studies were based on a comprehensive set of theoretical calculations, numerical simulations and experiments. A powerful simulation tool has been developed combining conventional softwares for SR simulation and optics design, thus allowing t...

  1. SU-D-BRA-06: Dual-Energy Chest CT: The Effects of Virtual Monochromatic Reconstructions On Texture Analysis Features

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, J; Duran, C; Stingo, F; Wei, W; Rao, A; Zhang, L; Court, L; Erasmus, J; Godoy, M [UT MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: To characterize the effect of virtual monochromatic reconstructions on several commonly used texture analysis features in DECT of the chest. Further, to assess the effect of monochromatic energy levels on the ability of these textural features to identify tissue types. Methods: 20 consecutive patients underwent chest CTs for evaluation of lung nodules using Siemens Somatom Definition Flash DECT. Virtual monochromatic images were constructed at 10keV intervals from 40–190keV. For each patient, an ROI delineated the lesion under investigation, and cylindrical ROI’s were placed within 5 different healthy tissues (blood, fat, muscle, lung, and liver). Several histogram- and Grey Level Cooccurrence Matrix (GLCM)-based texture features were then evaluated in each ROI at each energy level. As a means of validation, these feature values were then used in a random forest classifier to attempt to identify the tissue types present within each ROI. Their predictive accuracy at each energy level was recorded. Results: All textural features changed considerably with virtual monochromatic energy, particularly below 70keV. Most features exhibited a global minimum or maximum around 80keV, and while feature values changed with energy above this, patient ranking was generally unaffected. As expected, blood demonstrated the lowest inter-patient variability, for all features, while lung lesions (encompassing many different pathologies) exhibited the highest. The accuracy of these features in identifying tissues (76% accuracy) was highest at 80keV, but no clear relationship between energy and classification accuracy was found. Two common misclassifications (blood vs liver and muscle vs fat) accounted for the majority (24 of the 28) errors observed. Conclusion: All textural features were highly dependent on virtual monochromatic energy level, especially below 80keV, and were more stable above this energy. However, in a random forest model, these commonly used features were

  2. Does pupil constriction under blue and green monochromatic light exposure change with age?

    Science.gov (United States)

    Daneault, Véronique; Vandewalle, Gilles; Hébert, Marc; Teikari, Petteri; Mure, Ludovic S; Doyon, Julien; Gronfier, Claude; Cooper, Howard M; Dumont, Marie; Carrier, Julie

    2012-06-01

    Many nonvisual functions are regulated by light through a photoreceptive system involving melanopsin-expressing retinal ganglion cells that are maximally sensitive to blue light. Several studies have suggested that the ability of light to modulate circadian entrainment and to induce acute effects on melatonin secretion, subjective alertness, and gene expression decreases during aging, particularly for blue light. This could contribute to the documented changes in sleep and circadian regulatory processes with aging. However, age-related modification in the impact of light on steady-state pupil constriction, which regulates the amount of light reaching the retina, is not demonstrated. We measured pupil size in 16 young (22.8±4 years) and 14 older (61±4.4 years) healthy subjects during 45-second exposures to blue (480 nm) and green (550 nm) monochromatic lights at low (7×10(12) photons/cm2/s), medium (3×10(13) photons/cm2/s), and high (10(14) photons/cm2/s) irradiance levels. Results showed that young subjects had consistently larger pupils than older subjects for dark adaptation and during all light exposures. Steady-state pupil constriction was greater under blue than green light exposure in both age groups and increased with increasing irradiance. Surprisingly, when expressed in relation to baseline pupil size, no significant age-related differences were observed in pupil constriction. The observed reduction in pupil size in older individuals, both in darkness and during light exposure, may reduce retinal illumination and consequently affect nonvisual responses to light. The absence of a significant difference between age groups for relative steady-state pupil constriction suggests that other factors such as tonic, sympathetic control of pupil dilation, rather than light sensitivity per se, account for the observed age difference in pupil size regulation. Compared to other nonvisual functions, the light sensitivity of steady-state pupil constriction appears to

  3. Human wavelength discrimination of monochromatic light explained by optimal wavelength decoding of light of unknown intensity.

    Directory of Open Access Journals (Sweden)

    Li Zhaoping

    Full Text Available We show that human ability to discriminate the wavelength of monochromatic light can be understood as maximum likelihood decoding of the cone absorptions, with a signal processing efficiency that is independent of the wavelength. This work is built on the framework of ideal observer analysis of visual discrimination used in many previous works. A distinctive aspect of our work is that we highlight a perceptual confound that observers should confuse a change in input light wavelength with a change in input intensity. Hence a simple ideal observer model which assumes that an observer has a full knowledge of input intensity should over-estimate human ability in discriminating wavelengths of two inputs of unequal intensity. This confound also makes it difficult to consistently measure human ability in wavelength discrimination by asking observers to distinguish two input colors while matching their brightness. We argue that the best experimental method for reliable measurement of discrimination thresholds is the one of Pokorny and Smith, in which observers only need to distinguish two inputs, regardless of whether they differ in hue or brightness. We mathematically formulate wavelength discrimination under this wavelength-intensity confound and show a good agreement between our theoretical prediction and the behavioral data. Our analysis explains why the discrimination threshold varies with the input wavelength, and shows how sensitively the threshold depends on the relative densities of the three types of cones in the retina (and in particular predict discriminations in dichromats. Our mathematical formulation and solution can be applied to general problems of sensory discrimination when there is a perceptual confound from other sensory feature dimensions.

  4. Does pupil constriction under blue and green monochromatic light exposure change with age?

    Science.gov (United States)

    Daneault, Véronique; Vandewalle, Gilles; Hébert, Marc; Teikari, Petteri; Mure, Ludovic S.; Doyon, Julien; Gronfier, Claude; Cooper, Howard M.; Dumont, Marie; Carrier, Julie

    2017-01-01

    Many non-visual functions are regulated by light through a photoreceptive system involving melanopsin-expressing retinal ganglion cells that are maximally sensitive to blue light. Several studies have suggested that the ability of light to modulate circadian entrainment and to induce acute effects on melatonin secretion, subjective alertness and gene expression, decreases during aging, particularly for blue light. This could contribute to the documented changes in sleep and circadian regulatory processes with aging. However, age-related modification in the impact of light on steady-state pupil constriction, which regulates the amount of light reaching the retina, is not demonstrated. We measured pupil size in 16 young (22.8±4y) and 14 older (61±4.4y) healthy subjects during 45s exposures to blue (480nm) and green (550nm) monochromatic lights at low (7×1012 photons/cm2/s), medium (3×1013 photons/cm2/s), and high (1014 photons/cm2/s) irradiance levels. Results showed that young subjects had consistently larger pupils than older subjects, for dark adaptation and during all light exposures. Steady-state pupil constriction was greater under blue than green light exposure in both age groups and increased with increasing irradiance. Surprisingly, when expressed in relation to baseline pupil size, no significant age-related differences were observed in pupil constriction. The observed reduction in pupil size in older individuals, both in darkness and during light exposure, may reduce retinal illumination and consequently affect non-visual responses to light. The absence of a significant difference between age groups for relative steady-state pupil constriction suggests that other factors such as tonic, sympathetic control of pupil dilation, rather than light sensitivity per se, account for the observed age difference in pupil size regulation. Compared to other nonvisual functions, the light sensitivity of steady-state pupil constriction appears to remain relatively

  5. High resistance modulation by the electric field based on La0.9Sr0.1MnO3/SrTiO3/Si structure

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A field-effect configuration based on La0.9Sr0.1MnO3/SrTiO3/Si structure is fabricated on Si substrate by laser molecular-beam epitaxy. The resistance modulation by electric field of the La0.9Sr0.1MnO3/SrTiO3/Si structure is investigated in detail. An evident resistance modulation effect is observed at 80 K. The channel resistance modulation by field effect reaches 1.4×107% and 2.6×106% when VDS are -2 and -6.5 V, respectively. The ON/OFF ratio of approximately 4000 is obtained. The present results are worthy of further investigations for potential applications of resistance modulation by electrostatic field in the heterostructures consisting of perovskite oxides and Si.

  6. Beam characterization of a monolithic ΔE/E silicon device

    Energy Technology Data Exchange (ETDEWEB)

    Agosteo, S. [INFN, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Politecnico di Milano, Dipartimento di Energia, Sezione di Ingegneria Nucleare - CeSNEF, via Ponzio 34/3, 20133 Milano (Italy); Barcellan, L. [INFN, Sezione di Padova, via Marzolo 8, 35131 Padova (Italy); Borsato, E. [INFN, Sezione di Padova, via Marzolo 8, 35131 Padova (Italy); Università di Padova, Dipartimento di Fisica e Astronomia, via Marzolo 8, 35131 Padova (Italy); D' Angelo, G. [INFN, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Politecnico di Milano, Dipartimento di Energia, Sezione di Ingegneria Nucleare - CeSNEF, via Ponzio 34/3, 20133 Milano (Italy); Dal Corso, F. [INFN, Sezione di Padova, via Marzolo 8, 35131 Padova (Italy); Fazzi, A. [INFN, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Politecnico di Milano, Dipartimento di Energia, Sezione di Ingegneria Nucleare - CeSNEF, via Ponzio 34/3, 20133 Milano (Italy); Gonella, F. [INFN, Sezione di Padova, via Marzolo 8, 35131 Padova (Italy); Introini, M.V. [INFN, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Politecnico di Milano, Dipartimento di Energia, Sezione di Ingegneria Nucleare - CeSNEF, via Ponzio 34/3, 20133 Milano (Italy); Lippi, I. [INFN, Sezione di Padova, via Marzolo 8, 35131 Padova (Italy); Lorenzoli, M. [INFN, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Politecnico di Milano, Dipartimento di Energia, Sezione di Ingegneria Nucleare - CeSNEF, via Ponzio 34/3, 20133 Milano (Italy); Pegoraro, M. [INFN, Sezione di Padova, via Marzolo 8, 35131 Padova (Italy); Pola, A.; Varoli, V. [INFN, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Politecnico di Milano, Dipartimento di Energia, Sezione di Ingegneria Nucleare - CeSNEF, via Ponzio 34/3, 20133 Milano (Italy); and others

    2015-04-11

    A full characterization of a ΔE/E monolithic silicon detector especially developed for microdosimetry was performed using monochromatic beams of α-particles and protons at the Italian National Laboratories of Legnaro at the CN van de Graaff accelerator. The investigation was performed in order to evaluate the limitations and the systematic effects affecting its use as a microdosimeter. The results can be extended to the standard use of these kind of devices as particle identifiers.

  7. Measurements of effective total macroscopic cross sections and effective energy of continuum beam

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Hisao [Rikkyo Univ., Yokosuka, Kanagawa (Japan). Inst. for Atomic Energy

    1998-03-01

    Two practically useful quantities are introduced in this study to characterize a continuum neutron beam and to describe transmission phenomena of the beam in field of quantitative neutron radiography: an effective energy instead of a peak energy or a mean energy of the spectrum and an effective total macroscopic (ETM) cross section instead of a total macroscopic (TM) cross section defined at the monochromatic energy. The effective energy was evaluated by means of energy dependence of ETM cross section. To realize the method a beam quality indicator (BQI) has been proposed recently. Several effective energies were measured for non-filtered, filtered neutron beams, and outputs of neutron guide tubes in world by the BQI. A thermal neutron beam and three beams modulated by Pb filters with different thicknesses are studied to measure ETM cross sections for various materials and summarized in a table. Validity of the effective energy determined by the BQI is discussed relating with ETM cross sections of materials. (author)

  8. High-Spin States in ~(86)Sr

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The previous works for high spins states of 86Sr were very scarce. In the past, the spin of highest level of 86Sr was 13 found by the reaction 84Kr(α, 2nγ)86Sr in 28 MeV. The current work updates the level scheme of 86Sr to get more information about high spin states in 86Sr.

  9. Coral Sr-U Thermometry

    Science.gov (United States)

    DeCarlo, T. M.; Gaetani, G. A.; Cohen, A. L.; Foster, G. L.; Alpert, A.; Stewart, J.

    2016-12-01

    Coral skeletons archive the past two millennia of climate variability in the oceans with unrivaled temporal resolution. However, extracting accurate temperature information from coral skeletons is confounded by "vital effects", which often override the temperature dependence of geochemical proxies. Here, we present a new approach to coral paleothermometry based on results of abiogenic precipitation experiments interpreted within a framework provided by a quantitative model of the coral biomineralization process. We conducted laboratory experiments to test the temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater, and we modeled the sensitivity of skeletal composition to processes occurring at the site of calcification. The model predicts that temperature can be accurately reconstructed from coral skeleton by combining Sr/Ca and U/Ca ratios into a new proxy, Sr-U. We tested the model predictions with measured Sr/Ca and U/Ca ratios of fourteen Porites sp. corals collected from the tropical Pacific Ocean and the Red Sea, with a subset also analyzed using the boron isotope (δ11B) pH proxy. Observed relationships among Sr/Ca, U/Ca, and δ11B agree with model predictions, indicating that the model accounts for the key features of the coral biomineralization process. We calibrated Sr-U to instrumental temperature records and found that it captures 93% of mean annual variability (26-30 °C) and predicts temperature within 0.5 °C (1 σ). Conversely, Sr/Ca alone has an error of prediction of 1 °C and often diverges from observed temperature by 3 °C or more. Many of the problems afflicting Sr/Ca - including offsets among neighboring corals and decouplings from temperature during coral stress events - are reconciled by Sr-U. By accounting for the influence of the coral biomineralization process, the Sr-U thermometer may offer significantly improved reliability for reconstructing ocean temperatures from coral

  10. Wave-flume experiments of soft-rock cliff erosion under monochromatic waves

    Science.gov (United States)

    Regard, Vincent; Astruc, Dominique; Caplain, Bastien

    2017-04-01

    We investigate how cliffs erode under wave attack. Rocky coast erosion works through cycles, each one corresponding to three successive phases: (i) notch creation at cliff toe by mechanical action of waves, (ii) cliff fracturation leading to collapse, and (iii) evacuation of scree aprons by waves and currents. We performed experiments in a 5m x 14cm x 25cm wave flume (15 cm water depth) to investigate how waves are eroding a rocky coast. The cliff is made of wet sand and models a relatively soft rock. We used 3 different grain size (D50 = 0.28-0.41-0.48 mm), changing the cliff rheology. Waves are monochromatic; their height and period differ for the various experiments. Actual wave parameters are estimated by capacitive probes located offshore. The experiments are monitored by two video cameras both on the side and above the flume. Pictures are taken at a rate of 1Hz during the first 4h and then the rate is decreased to 0.1Hz till the end of experiment (about 1 day). The monitoring ensure a confident characterization of experiments in terms of waves (surf similarity parameter ξ and the incident wave energy flux F) and in terms of sediment (Dean number Ω and Shields number θb at breakers). Experiments begin by an initial phase of quick cliff retreat. Then the system evolves with slower cliff retreat. We focus on bottom morphology which we characterize in function of wave forcing (ξ, F). We show that the bottom morphology mainly depends on ξ. For our reference sediment (Dm = 0.41 mm), we observed: (i) surging breakers on a steep terrace (type T1) for ξ > 0.65; (ii)collapsing breakers on a bared profile attached to the inner platform (type T2) for 0.55< ξ <0.6; (iii) spilling breakers on gentle terrace (type T3) for F < 1.3 W/m and 0.55< ξ <0.6. Another bottom morphology, type T4, displays two sub-systems, an outer system with a double-bar profile where breaking waves are plunging, and an inner system with a T1, T2 or T3 profile. Some of these bottom

  11. Hard X-ray emission spectroscopy with pink beam

    Energy Technology Data Exchange (ETDEWEB)

    Kvashnina, Kristina O.; Rossberg, Andre; Exner, Joerg; Scheinost, Andreas C. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Molecular Structures

    2017-06-01

    Valence-band X-ray emission spectroscopy (XES) with a ''pink beam'', i.e. a beam with large energy bandwidth produced by a double-multilayer monochromator, is introduced here to overcome the weak count rate of monochromatic beams produced by conventional double-crystal monochromators. Our results demonstrate that - in spite of the large bandwidth in the order of 100 eV - the high spectral resolution of the Johann-type spectrometer is maintained, while the two orders of magnitude higher flux greatly reduces the required counting time. The short working distance Johann-type X-ray emission spectrometer and multilayer monochromator is available at ROBL.

  12. Gamma-beam propagation in the anisotropic medium

    CERN Document Server

    Maisheev, V A

    2000-01-01

    Propagation of gamma-beam in the anisotropic medium is considered. The simpliest example of such a medium of the general type is a combination of the two linearly polarized monochromatic laser waves with different frequencies (dichromatic wave). The optical properties of this combination are described with the use of the permittivity tensor. The refractive indices and polarization characteristics of normal electromagnetic waves propagating in the anisotropic medium are found. The relations, describing variations of gamma-beam intensity and Stokes parameters as functions of propagation length are obtained. The influence of laser wave intensity on the propagation process are calculated. The gamma-beam intensity losses in the dichromatic wave depend on the initial circular polarization of gamma-quanta. This effect is also applied to the single crystals, which are oriented in some regions of coherent pair production. In principle, the single crystal sensitivity to a circular polarization can be used for determina...

  13. Radiation Pressure Force from Optical Cycling on a Polyatomic Molecule SrOH

    Science.gov (United States)

    Kozyryev, Ivan; Baum, Louis; Matsuda, Kyle; Sedlack, Alex; Hemmerling, Boerge; Doyle, John

    2016-05-01

    Polyatomic molecules hold promise for many applications in physics and chemistry due to their rotational and vibrational degrees of freedom. The starting point for our approach to the production of ultracold strontium monohydroxide (SrOH) is buffer-gas cooling followed by laser manipulation. Linear geometry, diagonal Franck-Condon factors, short radiative lifetimes and unresolved hyperfine splittings make SrOH a particularly attractive candidate for direct laser cooling. We report deflection of the SrOH beam through radiative force from optical cycling on the X~2Σ+ Ã2Π1 / 2 transition. We observe × 12 fluorescence enhancement with closed spin-rotation splitting and demonstrate cycling between different vibrational levels with the Sr O mode repumping laser. Observed deflection and detection signals correspond to the scattering of ~ 100 photons. Additional repumping laser for the bending mode would lead to scattering of ~ 1 , 000 photons allowing for transverse laser cooling of the SrOH beam. We will also describe our experimental efforts towards laser slowing and trapping of SrOH.

  14. Effect of monochromatic and combined light colour on performance, blood parameters, ovarian morphology and reproductive hormones in laying hens

    Directory of Open Access Journals (Sweden)

    Md. Rakibul Hassan

    2013-07-01

    Full Text Available We evaluated the effect of monochromatic and combined light emitting diode (LED light colour on performance, ovarian morphology, and reproductive hormone and biochemical blood parameters in laying hens. A total of 600 Hy-line Brown pullets, 12 weeks of age, were divided (25×4×6 = birds × replications × treatments as follows: red (R, green (G, blue (B, and combinations of R→G and R→G→B treatments. Fluorescent white light (W was the control. The results showed that higher egg production was found under the monochromatic R and combination R→G treatments, and that heavier eggs were laid by the B and G treatments (P<0.05. Consequently, better feed conversion ratio was attained in the R→G treatment. Serum follicle stimulating hormone and 17β-estradiol levels were significantly higher in the R and R→G treatments. B treated birds came into production 15 days later than those treated with R light. Organ weight (ovary and stroma and ovarian follicle numbers (1-3 and 4-6 mm were significantly higher in R treated birds, as well as serum glucose and triglyceride contents. Serum IgG concentrations and the heterophil to lymphocyte ratio were not influenced by light colour. In these laying hens, 14 h R with 2 h G light in the later part of the day increased reproductive hormone levels, ovarian weight, and follicle number and hence increased egg production. Thus, these results suggest that a combination of R→G light may be comparable with monochromatic R light to enhance egg production in laying hens.

  15. Steady state of a low-density ensemble of atoms in a monochromatic field taking into account recoil effects

    Science.gov (United States)

    Prudnikov, O. N.; Il'enkov, R. Ya.; Taichenachev, A. V.; Tumaikin, A. M.; Yudin, V. I.

    2011-06-01

    A method has been developed for obtaining the steady-state solution of a quantum kinetic equation for the atomic density matrix in an arbitrarily polarized monochromatic field with the complete inclusion of recoil effects and degeneracy of atomic levels in the projection of the angular momentum. This method makes it possible to obtain the most general solution beyond the previously accepted approximations (semiclassical approximation, secular approximation, etc.). In particular, it has been shown that the laser cooling temperature is a function of not only the depth of the optical potential (as was previously thought), but also the mass of an atom.

  16. Amplified spontaneous emission spectrum at the output of a diode amplifier saturated by an input monochromatic wave

    Science.gov (United States)

    Bogatov, A. P.; Drakin, A. E.; D'yachkov, N. V.; Gushchik, T. I.

    2016-08-01

    Expressions for the amplitudes of amplified spontaneous emission waves in a diode amplifier near the frequency ω0 of a 'strong' input monochromatic wave have been derived in terms of a random function of a stationary Gaussian process. We have found expressions for the spectral density of the amplitudes and shown that, on the red side of the spectrum with respect to frequency ω0, spontaneous emission waves obtain additional nonlinear gain, induced by the strong wave, whereas on the blue side of the spectrum an additional loss is induced. Such behaviour of the amplitudes of amplified waves agrees with previous results.

  17. Beam loading

    CERN Document Server

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  18. Characteristic, parametric, and diffracted transition X-ray radiation for observation of accelerated particle beam profile

    Science.gov (United States)

    Chaikovska, I.; Chehab, R.; Artru, X.; Shchagin, A. V.

    2017-07-01

    The applicability of X-ray radiation for the observation of accelerated particle beam profiles is studied. Three types of quasi-monochromatic X-ray radiation excited by the particles in crystals are considered: characteristic X-ray radiation, parametric X-ray radiation, diffracted transition X-ray radiation. Radiation is collected at the right angle to the particle beam direction. It is show that the most intensive differential yield of X-ray radiation from Si crystal can be provided by characteristic radiation at incident electron energies up to tens MeV, by parametric radiation at incident electron energies from tens to hundreds MeV, by diffracted transition X-ray radiation at GeV and multi-GeV electron energies. Therefore these kinds of radiation are proposed for application to beam profile observation in the corresponding energy ranges of incident electrons. Some elements of X-ray optics for observation of the beam profile are discussed. The application of the DTR as a source of powerful tunable monochromatic linearly polarized X-ray beam excited by a multi-GeV electron beam on the crystal surface is proposed.

  19. Depth of interaction and bias voltage depenence of the spectral response in a pixellated CdTe detector operating in time-over-threshold mode subjected to monochromatic X-rays

    Science.gov (United States)

    Fröjdh, E.; Fröjdh, C.; Gimenez, E. N.; Maneuski, D.; Marchal, J.; Norlin, B.; O'Shea, V.; Stewart, G.; Wilhelm, H.; Modh Zain, R.; Thungström, G.

    2012-03-01

    High stopping power is one of the most important figures of merit for X-ray detectors. CdTe is a promising material but suffers from: material defects, non-ideal charge transport and long range X-ray fluorescence. Those factors reduce the image quality and deteriorate spectral information. In this project we used a monochromatic pencil beam collimated through a 20μm pinhole to measure the detector spectral response in dependance on the depth of interaction. The sensor was a 1mm thick CdTe detector with a pixel pitch of 110μm, bump bonded to a Timepix readout chip operating in Time-Over-Threshold mode. The measurements were carried out at the Extreme Conditions beamline I15 of the Diamond Light Source. The beam was entering the sensor at an angle of \\texttildelow20 degrees to the surface and then passed through \\texttildelow25 pixels before leaving through the bottom of the sensor. The photon energy was tuned to 77keV giving a variation in the beam intensity of about three orders of magnitude along the beam path. Spectra in Time-over-Threshold (ToT) mode were recorded showing each individual interaction. The bias voltage was varied between -30V and -300V to investigate how the electric field affected the spectral information. For this setup it is worth noticing the large impact of fluorescence. At -300V the photo peak and escape peak are of similar height. For high bias voltages the spectra remains clear throughout the whole depth but for lower voltages as -50V, only the bottom part of the sensor carries spectral information. This is an effect of the low hole mobility and the longer range the electrons have to travel in a low field.

  20. High-quality ion beams from a nanometric double-layer target and their application to hadron-therapy

    CERN Document Server

    Grech, M; Nuter, R; Grémillet, L; Lefebvre, E

    2010-01-01

    The production of ion beams from the interaction of a circularly polarized laser pulse with a nanometric double-layer target is discussed in the regime where all electrons are expelled from the target by the laser radiation pressure. Quasi-monochromatic, well-collimated ion beams are observed in two-dimensional particle-in-cell simulations. The ion beam properties are derived from a simple analytical model, and the possibility to control those properties by using a laser-pulse with sharp-rising edge is discussed. Application to hadron-therapy is finally considered.

  1. Transmission Electron Study of Heteroepitaxial Growth in the BiSrCaCuO System

    OpenAIRE

    Chaiken, A.; Wall, M. A.; Howell, R. H.; Bozovic, I.; Eckstein, J.N.; Virshup, G. F.

    1996-01-01

    Films of Bi$\\rm _2$Sr$\\rm _2$CaCu$\\rm _2$O$\\rm _8$ and Bi$\\rm _2$Sr$\\rm _2$CuO$\\rm _6$ have been grown using Atomic-Layer-by-Layer Molecular Beam Epitaxy (ALL-MBE) on lattice-matched substrates. These materials have been combined with layers of closely-related metastable compounds like Bi$\\rm _2$Sr$\\rm _2$Ca$\\rm _7$Cu$\\rm _8$O$\\rm _{20}$ (2278) and rare-earth-doped compounds like Bi$\\rm _2$Sr$\\rm _2$Dy$\\rm _x$Ca$\\rm _{1-x}$Cu$\\rm _2$O$\\rm _8$ (Dy:2212) to form heterostructures with unique sup...

  2. Tuning thermal conductivity in homoepitaxial SrTiO{sub 3} films via defects

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Charles M. [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853-1501 (United States); Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Wilson, Richard B.; Cahill, David G. [Department of Materials Science and Engineering and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States); Schäfer, Anna; Schubert, Jürgen [Peter Grünberg Institute (PGI9-IT), JARA-Fundamentals of Future Information Technology, Research Centre Jülich, D-52425 Jülich (Germany); Mundy, Julia A.; Holtz, Megan E. [School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States); Muller, David A. [School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853 (United States); Schlom, Darrell G. [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853-1501 (United States); Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853 (United States)

    2015-08-03

    We demonstrate the ability to tune the thermal conductivity of homoepitaxial SrTiO{sub 3} films deposited by reactive molecular-beam epitaxy by varying growth temperature, oxidation environment, and cation stoichiometry. Both point defects and planar defects decrease the longitudinal thermal conductivity (k{sub 33}), with the greatest decrease in films of the same composition observed for films containing planar defects oriented perpendicular to the direction of heat flow. The longitudinal thermal conductivity can be modified by as much as 80%—from 11.5 W m{sup −1}K{sup −1} for stoichiometric homoepitaxial SrTiO{sub 3} to 2 W m{sup −1}K{sup −1} for strontium-rich homoepitaxial Sr{sub 1+δ}TiO{sub x} films—by incorporating (SrO){sub 2} Ruddlesden-Popper planar defects.

  3. Transport in ferromagnetic GdTiO3/SrTiO3 heterostructures

    Science.gov (United States)

    Moetakef, Pouya; Zhang, Jack Y.; Kozhanov, Alexander; Jalan, Bharat; Seshadri, Ram; Allen, S. James; Stemmer, Susanne

    2011-03-01

    Epitaxial GdTiO3/SrTiO3 structures with different SrTiO3 layer thicknesses are grown on (001) (LaAlO3)0.3(Sr2AlTaO6)0.7 substrate surfaces by hybrid molecular beam epitaxy. It is shown that the formation of the pyrochlore (Gd2Ti2O7) phase can be avoided if GdTiO3 is grown by shuttered growth, supplying alternating monolayer doses of Gd and of the metalorganic precursor that supplies both Ti and O. Phase-pure GdTiO3 films grown by this approach exhibit magnetic ordering with a Curie temperature of 30 K. The electrical transport characteristics can be understood as being dominated by a conductive interface layer within the SrTiO3.

  4. Epitaxial SrO interfacial layers for HfO2-Si gate stack scaling

    Science.gov (United States)

    Marchiori, C.; Frank, M. M.; Bruley, J.; Narayanan, V.; Fompeyrine, J.

    2011-01-01

    We discuss the structural and electrical properties of scaled 2 nm HfO2/SrO gate stacks. Thin SrO layers are deposited by molecular beam epitaxy onto (001) p-Si substrates as alternative passivating interfacial layers (ILs) to SiO2. X-ray photoelectron spectroscopy and transmission electron microscopy show that, despite some HfO2-SrO intermixing, the SrO IL acts as a barrier against HfxSiy and SiO2 formation during high-κ deposition. Electrical measurements on metal-oxide-semiconductor capacitors with TiN metal gates integrated in a low-temperature process flow reveal an equivalent oxide thickness of 5 Å with competitive leakage current and hysteresis and a negative flat band voltage shift, suitable for n-channel transistors.

  5. Action of low-energy monochromatic coherent light on the stability of retinal lysosomes

    Science.gov (United States)

    Metelitsina, Irina P.; Leus, N. F.

    1995-05-01

    The data had been obtained during the experiment in vitro by irradiation of solubilized lysosomal enzymes, retinal homogenates and native lysosomes enabled us to conclude that the laser beam ((lambda) equals 632.8 nm, power density from 0.1 to 15.0 mWt/cm2) acts on the level of membranous structures of lysosomes. During irradiation of rabbits eyes in vitro with an unfocused laser beam (power density on the cornea aur face from 0.01 to 15.0 mWt/cm2 was shown, that low-energy, ranged from 0.01 to 1.0 mWt/cm2 promotes stabilization of lysosomal membranes. Irradiation with laser beam of 8.0 mWt/cm2 and more power induces destabilization of lysosomal membranes. We have also shown that vitamins A and E effecting membranotropic on lysosomes may be corrected by low-energy radiation of helium-neon laser. It is substantiated experimentally that the stabilizing effect of vitamin E may be intensified in case of the combined action of laser radiation on lysosomes. The labilizing effect of vitamin A on membranes of organelles, as was studied, may be weakened by application of laser radiation of low intensities.

  6. The effect of pupil size on stimulation of the melanopsin containing retinal ganglion cells, as evaluated by monochromatic pupillometry

    DEFF Research Database (Denmark)

    Nissen, Claus Jeppe; Sander, Birgit; Lund-Andersen, Henrik

    2012-01-01

    Purpose: To evaluate the influence of the size of the light exposed pupil in one eye on the pupillary light reflex of the other eye. Method: Using a monochromatic pupillometer, the left eye in each of 10 healthy subjects was exposed to 20¿s of monochromatic light of luminance 300¿cd/m(2), first red...... (660¿nm) and in a following session, blue (470¿nm) light. The consensual pupillary diameter in the right eye was continuously measured before, during, and after light exposure. Subsequently, Tropicamide 1% or Pilocarpine 2% was instilled into the left eye and when the pupil was either maximally dilated...... or contracted, the entire sequence of red and blue light exposure repeated. After at least 3¿days, when the effect of the eye drop had subsided, the entire experiment was repeated, this time employing the other substance. Results: Prior dilatation of the left pupil augmented the post light contraction to blue...

  7. Analysis of gas exchange, stomatal behaviour and micronutrients uncovers dynamic response and adaptation of tomato plants to monochromatic light treatments.

    Science.gov (United States)

    O'Carrigan, Andrew; Babla, Mohammad; Wang, Feifei; Liu, Xiaohui; Mak, Michelle; Thomas, Richard; Bellotti, Bill; Chen, Zhong-Hua

    2014-09-01

    Light spectrum affects the yield and quality of greenhouse tomato, especially over a prolonged period of monochromatic light treatments. Physiological and chemical analysis was employed to investigate the influence of light spectral (blue, green and red) changes on growth, photosynthesis, stomatal behaviour, leaf pigment, and micronutrient levels. We found that plants are less affected under blue light treatment, which was evident by the maintenance of higher A, gs, Tr, and stomatal parameters and significantly lower VPD and Tleaf as compared to those plants grown in green and red light treatments. Green and red light treatments led to significantly larger increase in the accumulation of Fe, B, Zn, and Cu than blue light. Moreover, guard cell length, width, and volume all showed highly significant positive correlations to gs, Tr and negative links to VPD. There was negative impact of monochromatic lights-induced accumulation of Mn, Cu, and Zn on photosynthesis, leaf pigments and plant growth. Furthermore, most of the light-induced significant changes of the physiological traits were partially recovered at the end of experiment. A high degree of morphological and physiological plasticity to blue, green and red light treatments suggested that tomato plants may have developed mechanisms to adapt to the light treatments. Thus, understanding the optimization of light spectrum for photosynthesis and growth is one of the key components for greenhouse tomato production.

  8. Measurement of Monochromatic Emissivity of Cement Clinker with Various Fe2O3 Content at High Temperature

    Institute of Scientific and Technical Information of China (English)

    Z.J.Ye; C.F.Ma; 等

    1996-01-01

    An applicatiopn of the optical pyrometer is studied for measuring monochromatic emissivities of cement clinker with various Fe2O3 contnet.The idsa of using “brightness temperature” is introduced into the eimssivity measurement.In this method,there is no need for measuring an actual temperature of sample surfaces,only with determining both brightness temperatures of a sample and a blackbody can the required emissivity be evaluated according to Wien's radiation law.In practice,the cement clinker is regarded as a greybody,the monochromatic emissivity is approximately equal to the total emissivity,so a single-colour optical pyrometer is applied for this purpose,Test measurements are carried out on 10 kinds of cement clinkers,Experimental data are treated by the least square method.As a result ,the emissivity variation with temperature at a certain Fe2O3 content is quite well represented by εn=a+bT.Furthermore,this work first reported that the eimissivities of cement clinker change consierably with Fe2O3 contents.In multiple cement production this conclusion is very important.

  9. 6D phase space electron beam analysis and machine sensitivity studies for ELI-NP GBS

    Science.gov (United States)

    Giribono, A.; Bacci, A.; Curatolo, C.; Drebot, I.; Palumbo, L.; Petrillo, V.; Rossi, A. R.; Serafini, L.; Vaccarezza, C.; Vannozzi, A.; Variola, A.

    2016-09-01

    The ELI-NP Gamma Beam Source (GBS) is now under construction in Magurele-Bucharest (RO). Here an advanced source of gamma photons with unprecedented specifications of brilliance (>1021), monochromaticity (0.5%) and energy tunability (0.2-19.5 MeV) is being built, based on Inverse Compton Scattering in the head-on configuration between an electron beam of maximum energy 750 MeV and a high quality high power ps laser beam. These requirements make the ELI-NP GBS an advanced and challenging gamma ray source. The electron beam dynamics analysis and control regarding the machine sensitivity to the possible jitter and misalignments are presented. The effects on the beam quality are illustrated providing the basis for the alignment procedure and jitter tolerances.

  10. Nuclear physics with advanced brilliant gamma beams at ELI-NP

    Science.gov (United States)

    Ur, Călin A.; Filipescu, Dan; Gheorghe, Ioana; Iancu, Violeta; Suliman, Gabriel; Teşileanu, Ovidiu

    2016-01-01

    The Extreme Light Infrastructure - Nuclear Physics facility is dedicated to nuclear physics studies with the use of extreme electromagnetic radiation. One of the main research system to be installed and operated in the facility is an outstanding high brilliance gamma beam system. The Gamma Beam System of ELI-NP will produce intense, quasi-monochromatic gamma beams via inverse Compton scattering of short laser pulses on relativistic electron beam pulses. The gamma beams available at ELI-NP will allow for the performance of photo-nuclear reactions aiming to reveal the intimate structure of the atomic nucleus. Nuclear Resonance Fluorescence, photo-fission, photo-disintegration reactions above the particle threshold will be used to study the dipole response of nuclei, the structure of the Pygmy resonances, nuclear processes relevant for astrophysics, production and study of exotic neutron-rich nuclei.

  11. Nuclear physics with advanced brilliant gamma beams at ELI–NP

    Directory of Open Access Journals (Sweden)

    Ur Călin A.

    2016-01-01

    Full Text Available The Extreme Light Infrastructure - Nuclear Physics facility is dedicated to nuclear physics studies with the use of extreme electromagnetic radiation. One of the main research system to be installed and operated in the facility is an outstanding high brilliance gamma beam system. The Gamma Beam System of ELI–NP will produce intense, quasi–monochromatic gamma beams via inverse Compton scattering of short laser pulses on relativistic electron beam pulses. The gamma beams available at ELI–NP will allow for the performance of photo-nuclear reactions aiming to reveal the intimate structure of the atomic nucleus. Nuclear Resonance Fluorescence, photo-fission, photo-disintegration reactions above the particle threshold will be used to study the dipole response of nuclei, the structure of the Pygmy resonances, nuclear processes relevant for astrophysics, production and study of exotic neutron–rich nuclei.

  12. Fabrication and convergent X-ray nanobeam diffraction characterization of submicron-thickness SrTiO3 crystalline sheets

    Directory of Open Access Journals (Sweden)

    J. A. Tilka

    2016-12-01

    Full Text Available The creation of thin SrTiO3 crystals from (001-oriented SrTiO3 bulk single crystals using focused ion beam milling techniques yields sheets with submicron thickness and arbitrary orientation within the (001 plane. Synchrotron x-ray nanodiffraction rocking curve widths of these SrTiO3 sheets are less than 0.02°, less than a factor of two larger than bulk SrTiO3, making these crystals suitable substrates for epitaxial thin film growth. The change in the rocking curve width is sufficiently small that we deduce that dislocations are not introduced into the SrTiO3 sheets. Observed lattice distortions are consistent with a low concentration of point defects.

  13. Fabrication and convergent X-ray nanobeam diffraction characterization of submicron-thickness SrTiO3 crystalline sheets

    Science.gov (United States)

    Tilka, J. A.; Park, J.; Sampson, K. C.; Cai, Z.; Evans, P. G.

    2016-12-01

    The creation of thin SrTiO3 crystals from (001)-oriented SrTiO3 bulk single crystals using focused ion beam milling techniques yields sheets with submicron thickness and arbitrary orientation within the (001) plane. Synchrotron x-ray nanodiffraction rocking curve widths of these SrTiO3 sheets are less than 0.02°, less than a factor of two larger than bulk SrTiO3, making these crystals suitable substrates for epitaxial thin film growth. The change in the rocking curve width is sufficiently small that we deduce that dislocations are not introduced into the SrTiO3 sheets. Observed lattice distortions are consistent with a low concentration of point defects.

  14. Growth and characterization of charge carrier spatially confined SrMnO3/La0.7Sr0.3MnO3/SrMnO3 trilayers

    Science.gov (United States)

    Galdi, A.; Sacco, C.; Orgiani, P.; Romeo, F.; Maritato, L.

    2017-02-01

    (SrMnO3)x/(La0.7Sr0.3MnO3)y/(SrMnO3)z (x,y,z=number of unit cells) trilayers have been grown using a Reflection High Energy Electron Diffraction calibrated layer-by-layer molecular beam epitaxy technique. X-Ray Reflectivity and X-Ray Diffraction measurements confirm the structural quality and the abruptness of the interfaces. Electrical transport property analysis as a function of temperature show effects related to the spatial confinement of the charge carriers induced by the layering. These results are important in view of future developments of oxide based heterostructures for innovative quantum devices.

  15. Genesis of Sr Isotopes in Groundwater of Hebei Plain

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To analyze the genesis of Sr isotopes in groundwater of Hebei plain, time-accumulative effect of 87Sr/86Sr ratio was studied. It is shown that 87Sr/86Sr ratio increases with the increasing age and depth of groundwater and has a positive correlation to 4Heexc and a negative correlation to δ18O and δD.The groundwater is divided into three groups to discuss the relation between 87Sr/86Sr ratio and Sr2+ content: ① moderate Sr2+ content and higher 87Sr/86Sr ratio (water Ⅰ); ② lower Sr2+ content and higher 87Sr/86Sr ratio (water Ⅱ); and ③ higher Sr2+ content and lower 87Sr/86Sr ratio (water Ⅲ), that is hot water. On the basis of integrated analysis, it was considered that ① the radiogenic Sr in the Quaternary groundwater (Q4-Q1) originates from weathering of silicate rich in Na and Rb, mainly from plagioclase; ② the radiogenic Sr of hot water in Huanghua port is attributed to carbonate dissolution, with lower 87Sr/86Sr ratio and higher Sr/Na ratio; ③ the recharge area is laterally recharged by the groundwater flowing through igneous and metamorphic rocks, with moderate 87Sr/86Sr ratio. However, the formation mechanism of Sr isotopes in Tertiary groundwater needs further studies.

  16. Bunch Length Measurements With Laser/SR Cross-Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Timothy; /Stanford U., Phys. Dept.; Daranciang, Dan; /Stanford U., Phys. Dept.; Lindenberg, Aaron; /Stanford U., Phys. Dept.; Corbett, Jeff; /SLAC; Fisher, Alan; /SLAC; Goodfellow, John; /SLAC; Huang, Xiaobiao; /SLAC; Mok, Walter; /SLAC; Safranek, James; /SLAC; Wen, Haidan; /SLAC

    2012-07-06

    By operating SPEAR3 in low-{alpha} mode the storage ring can generate synchrotron radiation pulses of order 1ps. Applications include pump-probe x-ray science and the production of THz radiation in the CSR regime. Measurements of the bunch length are difficult, however, because the light intensity is low and streak cameras typically provide resolution of only a few ps. Tests are now underway to resolve the short bunch length using cross-correlation between a 60-fs Ti:Sapphire laser and the visible SR beam in a BBO crystal. In this paper we report on the experimental setup, preliminary measurements and prospects for further improvement.

  17. Bunch Length Measurements With Laser/SR Cross-Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Timothy; /Stanford U., Phys. Dept.; Daranciang, Dan; /Stanford U., Phys. Dept.; Lindenberg, Aaron; /Stanford U., Phys. Dept.; Corbett, Jeff; /SLAC; Fisher, Alan; /SLAC; Goodfellow, John; /SLAC; Huang, Xiaobiao; /SLAC; Mok, Walter; /SLAC; Safranek, James; /SLAC; Wen, Haidan; /SLAC

    2012-07-06

    By operating SPEAR3 in low-{alpha} mode the storage ring can generate synchrotron radiation pulses of order 1ps. Applications include pump-probe x-ray science and the production of THz radiation in the CSR regime. Measurements of the bunch length are difficult, however, because the light intensity is low and streak cameras typically provide resolution of only a few ps. Tests are now underway to resolve the short bunch length using cross-correlation between a 60-fs Ti:Sapphire laser and the visible SR beam in a BBO crystal. In this paper we report on the experimental setup, preliminary measurements and prospects for further improvement.

  18. Cenozoic seawater Sr/Ca evolution

    Science.gov (United States)

    Sosdian, Sindia M.; Lear, Caroline H.; Tao, Kai; Grossman, Ethan L.; O'Dea, Aaron; Rosenthal, Yair

    2012-10-01

    Records of seawater chemistry help constrain temporal variations in geochemical processes that impact the global carbon cycle and climate through Earth's history. Here we reconstruct Cenozoic seawater Sr/Ca (Sr/Casw) using fossil Conus and turritellid gastropod Sr/Ca. Combined with an oxygen isotope paleotemperature record from the same samples, the gastropod record suggests that Sr/Caswwas slightly higher in the Eocene (˜11.4 ± 3 mmol/mol) than today (˜8.54 mmol/mol) and remained relatively stable from the mid- to late Cenozoic. We compare our gastropod Cenozoic Sr/Casw record with a published turritellid gastropod Sr/Casw record and other published biogenic (benthic foraminifera, fossil fish teeth) and inorganic precipitate (calcite veins) Sr/Caswrecords. Once the uncertainties with our gastropod-derived Sr/Casw are taken into account the Sr/Casw record agrees reasonably well with biogenic Sr/Caswrecords. Assuming a seawater [Ca] history derived from marine evaporite inclusions, all biogenic-based Sr/Casw reconstructions imply decreasing seawater [Sr] through the Cenozoic, whereas the calcite vein Sr/Casw reconstruction implies increasing [Sr] through the Cenozoic. We apply a simple geochemical model to examine the implications of divergence among these seawater [Sr] reconstructions and suggest that the interpretation and uncertainties associated with the gastropod and calcite vein proxies need to be revisited. Used in conjunction with records of carbonate depositional fluxes, our favored seawater Sr/Ca scenarios point to a significant increase in the proportion of aragonite versus calcite deposition in shelf sediments from the Middle Miocene, coincident with the proliferation of coral reefs. We propose that this occurred at least 10 million years after the seawater Mg/Ca threshold was passed, and was instead aided by declining levels of atmospheric carbon dioxide.

  19. 88Sr/86Sr fractionation in inorganic aragonite and in corals

    Science.gov (United States)

    Fruchter, Noa; Eisenhauer, Anton; Dietzel, Martin; Fietzke, Jan; Böhm, Florian; Montagna, Paolo; Stein, Moti; Lazar, Boaz; Rodolfo-Metalpa, Riccardo; Erez, Jonathan

    2016-04-01

    Conflicting results have been reported for the stable Sr isotope fractionation, specifically with respect to the influence of temperature. In an experimental study we have investigated the stable Sr isotope systematics for inorganically precipitated and biogenic (coral) aragonite (natural and laboratory-cultured). Inorganic aragonite precipitation experiments were performed from natural seawater using the CO2 diffusion technique. The experiments were performed at different temperatures and different carbonate ion concentrations. 88Sr/86Sr of the inorganic aragonite precipitated in the experiments are 0.2‰ lighter than seawater, but showed no correlation to the water temperature or to CO32- concentration. Similar observations are made in different coral species (Cladocora caespitosa, Porites sp. and Acropora sp.), with identical fractionation from the bulk solution and no correlation to temperature or CO32- concentration. The lack of 88Sr/86Sr variability in corals at different environmental parameters and the similarity to the 88Sr/86Sr fractionation in inorganic aragonite may indicate a similar Sr incorporation mechanism in corals skeleton and inorganic aragonite, and therefore the previously proposed Rayleigh-based multi element model (Gaetani et al., 2011) cannot explain the process of Sr incorporation in the coral skeletal material. It is proposed that the relatively constant 88Sr/86Sr fractionation in aragonite can be used for paleo reconstruction of seawater 88Sr/86Sr composition. The seawater 88Sr/86Sr ratio reconstruction can be further used in calcite samples to reconstruct paleo precipitation rates.

  20. Possible insect vectors of phytoplasmas affiliated with subgroups 16SrI-B, 16SrI-C, 16SrIII-B and 16SrIII-P in Lithuania

    Science.gov (United States)

    Phytoplasma strains affiliated with groups 16SrI, 16SrIII, 16SrV, and 16SrXII have been found in Lithuania, but still little is known about insects that could transmit them. In this study, four phytoplasma strains belonging to phytoplasma subgroups 16SrI-B, 16SrI-C, 16SrIII-B and 16SrIII-P were id...

  1. Sr partitioning in the benthic foraminifera

    NARCIS (Netherlands)

    Langer, G.; Sadekov, A.; Thoms, S.; Keul, N.; Nehrke, G.; Mewes, A.; Greaves, M.; Misra, S.; Reichart, G.-J.; de Nooijer, L.J.; Bijma, J.; Elderfield, H.

    2016-01-01

    The shallow water benthic foraminifera Ammonia aomoriensis and Amphistegina lessonii were grown at differentseawater Sr/Ca and the test Sr/Ca ratio was determined by Laser Ablation - Inductively Coupled Plasma - MassSpectrometry. A. aomoriensis test Sr/Ca is positively correlated with seawater

  2. Beam collimator

    CERN Multimedia

    1977-01-01

    A four-block collimator installed on a control table for positioning the alignment reference marks. Designed for use with SPS secondary beams, the collimator operates under vacuum conditions. See Annual Report 1976 p. 121 and photo 7701014.

  3. Effect of Monochromatic Light on Expression of Estrogen Receptor (ER) and Progesterone Receptor (PR) in Ovarian Follicles of Chicken.

    Science.gov (United States)

    Liu, Lingbin; Li, Diyan; Gilbert, Elizabeth R; Xiao, Qihai; Zhao, Xiaoling; Wang, Yan; Yin, Huadong; Zhu, Qing

    2015-01-01

    Artificial illumination is widely used in modern poultry houses and different wavelengths of light affect poultry production and behaviour. In this study, we measure mRNA and protein abundance of estrogen receptors (ERs) and progesterone receptors (PRs) in order to investigate the effect of monochromatic light on egg production traits and gonadal hormone function in chicken ovarian follicles. Five hundred and fifty-two 19-wk-old laying hens were exposed to three monochromatic lights: red (RL; 660 nm), green (GL; 560 nm), blue (BL; 480 nm) and control cool white (400-760 nm) light with an LED (light-emitting diode). There were 4 identical light-controlled rooms (n = 138) each containing 3 replicate pens (46 birds per pen). Water was supplied ad libitum and daily rations were determined according to the nutrient suggestions for poultry. Results showed that under BL conditions there was an increase in the total number of eggs at 300 days of age and egg-laying rate during the peak laying period. The BL and GL extended the duration of the peak laying period. Plasma melatonin was lowest in birds reared under BL. Plasma estradiol was elevated in the GL-exposed laying hens, and GL and BL increased progesterone at 28 wk of age. In the granulosa layers of the fifth largest preovulatory follicle (F5), the third largest preovulatory follicle (F3) and the largest preovulatory follicle (F1), ERα mRNA was increased by BL and GL. Treatment with BL increased ERβ mRNA in granulosa layers of F5, F3 and F1, while GL increased ERβ mRNA in F5 and F3. There was a corresponding increase in abundance of the proteins in the granulosa layers of F5, with an increase in PR-B, generated via an alternative splice site, relative to PR-A. Treatment with BL also increased expression of PR mRNA in all of the granulosa layers of follicles, while treatment with GL increased expression of PR mRNA in granulosa layers of SYF(small yellow follicle), F5 and F1. These results indicate that blue and green

  4. Effect of Monochromatic Light on Expression of Estrogen Receptor (ER and Progesterone Receptor (PR in Ovarian Follicles of Chicken.

    Directory of Open Access Journals (Sweden)

    Lingbin Liu

    Full Text Available Artificial illumination is widely used in modern poultry houses and different wavelengths of light affect poultry production and behaviour. In this study, we measure mRNA and protein abundance of estrogen receptors (ERs and progesterone receptors (PRs in order to investigate the effect of monochromatic light on egg production traits and gonadal hormone function in chicken ovarian follicles. Five hundred and fifty-two 19-wk-old laying hens were exposed to three monochromatic lights: red (RL; 660 nm, green (GL; 560 nm, blue (BL; 480 nm and control cool white (400-760 nm light with an LED (light-emitting diode. There were 4 identical light-controlled rooms (n = 138 each containing 3 replicate pens (46 birds per pen. Water was supplied ad libitum and daily rations were determined according to the nutrient suggestions for poultry. Results showed that under BL conditions there was an increase in the total number of eggs at 300 days of age and egg-laying rate during the peak laying period. The BL and GL extended the duration of the peak laying period. Plasma melatonin was lowest in birds reared under BL. Plasma estradiol was elevated in the GL-exposed laying hens, and GL and BL increased progesterone at 28 wk of age. In the granulosa layers of the fifth largest preovulatory follicle (F5, the third largest preovulatory follicle (F3 and the largest preovulatory follicle (F1, ERα mRNA was increased by BL and GL. Treatment with BL increased ERβ mRNA in granulosa layers of F5, F3 and F1, while GL increased ERβ mRNA in F5 and F3. There was a corresponding increase in abundance of the proteins in the granulosa layers of F5, with an increase in PR-B, generated via an alternative splice site, relative to PR-A. Treatment with BL also increased expression of PR mRNA in all of the granulosa layers of follicles, while treatment with GL increased expression of PR mRNA in granulosa layers of SYF(small yellow follicle, F5 and F1. These results indicate that blue

  5. Resonant antineutrino induced electron capture with low energy bound-beta beams

    CERN Document Server

    Oldeman, R G C; Saitta, B

    2009-01-01

    Antineutrino induced electron capture is a resonant process that can have a larg e cross-section for beams of monochromatic antineutrinos. We calculate the cross-section of this process and investigate an experimental setup where monochromatic antineutrinos are produced from the bound-beta decay of fully ionized radioactive atoms in a storage ring. If the energy between the source and the target is well matched, the cross-sections can be significantly larger than the cross-sections of commonly used non-resonant processes. The rate that can be achieved at a small distance between the source and two targets of $10^3$ kg is up to one interaction per $8 .3\\cdot10^{18}$ decaying atoms. For a source-target distance corresponding to the first atmospheric neutrino osc illation maximum, the largest rate is one interaction per $3.2\\cdot10^{21}$ decaying atoms.

  6. Experimental intra-arterial administration of SR-2508 in the rabbit V2 carcinoma model

    Energy Technology Data Exchange (ETDEWEB)

    Coldwell, D.M.; Huff, J.; Marcellus, H.; Coldwell, S.G.

    1989-03-01

    The use of the nitroimidazole radiation sensitizers, misonidazole and SR-2508, has been limited by a variety of side-effects, principally peripheral neuropathies. To increase the effectiveness of radiosensitization and reduce the administered dose of the sensitizers, intra-arterial delivery of SR-2508 was performed and followed with 10Gy of 4 MeV photon beam radiotherapy in the rabbit V2 carcinoma tumour model. Comparison was made with rabbits treated with an identical dose of SR-2508 given intravenously prior to photon beam radiotherapy. Control animals were treated with radiation therapy only, intra-arterial SR-2508 only, or had no treatment. Neither radiation therapy alone nor SR-2508 alone had any effect on tumour growth. In the intra-arterial group, tumour growth was slower and size was significantly smaller than all other groups. Results suggest that the intra-arterial infusion of radiation sensitizer produces greater tumour response than intravenous infusion when each is combined with radiation therapy.

  7. Rapid method for determining Sr-89 and Sr-90 using Cherenkov and proportional counting; Schnellmethode zur Bestimmung von SR-89 und SR-90 durch Cerenkov- und Proportionalzaehlermessungen

    Energy Technology Data Exchange (ETDEWEB)

    Lange, S.; Wende, C.; Schwokowski, R.; Alisch-Mark, M.; Abraham, A.; Heinrich, T. [Staatliche Betriebsgesellschaft fuer Umwelt und Landwirtschaft, Radebeul (Germany)

    2016-07-01

    A rapid method for determining Sr-89 and Sr-90 in water, milk and biological samples has been developed and tested. After sample preparation strontium is separated by extraction chromatography using Sr resin. Eluate is divided and transfered to LSC vial and filter paper by SrCO{sub 3} precipitation. A Hidex 300 SL TDCR liquid scintillation counter and Thermo Fisher low level proportional counter have been used. Chemical yield of Sr-85 tracer is determined by Gamma spectroscopy. Uncertainty budget, decision threshold and detection limit are calculated in accordance with GUM and ISO 11929.

  8. Threshold collision-induced dissociation of Sr(2+)(H(2)O)(x) complexes (x=1-6): An experimental and theoretical investigation of the complete inner shell hydration energies of Sr(2+).

    Science.gov (United States)

    Carl, D R; Chatterjee, B K; Armentrout, P B

    2010-01-28

    The sequential bond energies of Sr(2+)(H(2)O)(x) complexes, where x=1-6, are determined by threshold collision-induced dissociation using a guided ion beam tandem mass spectrometer equipped with an electrospray ionization source. The electrospray source produces an initial distribution of Sr(2+)(H(2)O)(x) complexes, where x=6-9. Smaller Sr(2+)(H(2)O)(x) complexes, where x=1-5, are accessed using a recently developed in-source fragmentation technique that takes place in the high pressure region of a rf-only hexapole ion guide. This work constitutes the first experimental study for the complete inner shell of any multiply charged ion. The kinetic energy dependent cross sections are determined over a wide energy range to monitor all possible dissociation products and are modeled to obtain 0 and 298 K binding energies for loss of a single water molecule. These binding energies decrease monotonically for the Sr(2+)(H(2)O) complex to Sr(2+)(H(2)O)(6). Our experimental results agree well with previous literature results obtained by equilibrium and kinetic studies for x=5 and 6. Because there has been limited theory for the hydration of Sr(2+), we also present an in-depth theoretical study on the energetics of the Sr(2+)(H(2)O)(x) systems by employing several levels of theory with multiple effective core potentials for Sr and different basis sets for the water molecules.

  9. Atomic Resolution Imaging at an Ultralow Accelerating Voltage by a Monochromatic Transmission Electron Microscope

    Science.gov (United States)

    Morishita, Shigeyuki; Mukai, Masaki; Suenaga, Kazu; Sawada, Hidetaka

    2016-10-01

    Transmission electron microscopy using low-energy electrons would be very useful for atomic resolution imaging of specimens that would be damaged at higher energies. However, the resolution at low voltages is degraded because of geometrical and chromatic aberrations. In the present study, we diminish the effect of these aberrations by using a delta-type corrector and a monochromator. The dominant residual aberration in a delta-type corrector, which is the sixth-order three-lobe aberration, is counterbalanced by other threefold aberrations. Defocus spread caused by chromatic aberration is reduced by using a monochromated beam with an energy spread of 0.05 eV. We obtain images of graphene and demonstrate atomic resolution at an ultralow accelerating voltage of 15 kV.

  10. High Temperature μSR Experiments for Accelerator Developments

    Science.gov (United States)

    Ohmori, Chihiro; Koda, Akihiro; Miyake, Yasuhiro; Nishiyama, Kusuo; Shimomura, Koichiro; Schnase, Alexander; Ezura, Eiji; Hara, Keigo; Hasegawa, Katsushi; Nomura, Masahiro; Shimada, Taihei; Takata, Koji; Tamura, Fumihiko; Toda, Makoto; Yamamoto, Masanobu; Yoshii, Masahito

    High temperature μSR is a powerful technique to study magnetic materials. In J-PARC accelerator synchrotrons, the Rapid Cycling Synchrotron (RCS) and Main Ring (MR), a unique magnetic alloy-loaded cavity is used for the beam acceleration and much higher field gradient has been achieved. Such high field gradient cavities made a compact RCS possible by reducing the length for beam acceleration. Now, further upgrades of the J-PARC, RF cavities with higher RF voltage and less power loss in the magnetic core are needed for the MR. For the improvements of the magnetic property of magnetic alloy core, the high temperature μSR (muon Spin Rotation/Relaxation) was used to investigate the crystallization process of the material. Based on the measurement results, the test production of the large ring cores of a magnetic alloy, FT3L, was tried. The FT3L is the magnetic alloy which has two times better performance than the present one, FT3M. For the FT3L production, the magnetic annealing is needed to control the easy-magnetized axis of the crystalline. After the success of the test production, a mass production was started in the industry to replace all existing cavities in the MR. The first 5-cell FT3L cavity is assembled for the bench test before the installation in the accelerator tunnel. By the new cavities, the total RF voltage of J-PARC MR will be doubled to increase the beam power for neutrino experiment. In future, the cavities will be also used for the RCS to increase the beam power beyond 1 MW.

  11. Cylindrical shock waves in rotational axisymmetric non-ideal dusty gas with increasing energy under the action of monochromatic radiation

    Science.gov (United States)

    Sahu, P. K.

    2017-08-01

    The propagation of a cylindrical shock wave in a rotational axisymmetric non-ideal dusty gas under the action of monochromatic radiation with increasing energy, which has variable azimuthal and axial components of fluid velocity, is investigated. The dusty gas is assumed to be a mixture of non-ideal (or perfect) gas and small solid particles, in which solid particles are continuously distributed. Similarity solutions are obtained as well as the effects of the variation of the radiation parameters, the parameter of non-idealness of the gas, the mass concentration of solid particles in the mixture, the ratio of the density of solid particles to the initial density of the gas, and the piston velocity index are worked out in detail. The total energy of the shock wave is varying and increases with time. It is observed that the radiation parameter and the piston velocity index have opposite behaviour on the flow variables as well as the shock strength.

  12. Influence of monochromatic light on quality traits, nutritional, fatty acid, and amino acid profiles of broiler chicken meat.

    Science.gov (United States)

    Kim, M J; Parvin, R; Mushtaq, M M H; Hwangbo, J; Kim, J H; Na, J C; Kim, D W; Kang, H K; Kim, C D; Cho, K O; Yang, C B; Choi, H C

    2013-11-01

    The role of monochromatic lights was investigated on meat quality in 1-d-old straight-run broiler chicks (n = 360), divided into 6 light sources with 6 replicates having 10 chicks in each replicate. Six light sources were described as incandescent bulbs (IBL, as a control) and light-emitting diode (LED) light colors as white light (WL), blue light, red light (RL), green light, and yellow light. Among LED groups, the RL increased the concentration of monounsaturated fatty acids (P light produced by LED responded similar to the IBL light in influencing nutrient contents of meat. Moreover, LED is not decisive in improving fatty acid composition of meat. However, the role of IBL in reducing n-6:n-3 ratio and enhancing n-3 cannot be neglected. Among LED, WL is helpful in improving essential and nonessential amino acid contents of broiler meat.

  13. High spin states in stable nucleus 84Sr

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    High spin states of 84Sr were populated through the reaction 70Zn(18O,4n)84Sr at 75 MeV beam energy.Measurement of excitation function,γ-γ coincidences,directional correlation from oriented state (DCO) ratios and γ-transition intensities were performed using eight anticompton HPGe detectors and one planar HPGe detector.Based on the measured results,a new level scheme of 84Sr was established in which 12 new states and nearly 30 new γ-transitions were identified in the present work.The positive-parity states of the new level scheme were compared with the results from calculations in the framework of the projected shell model (PSM).One negative-parity band was extended to spin Iπ=19-and it can be found that in the high spin states,the γ-transition energies show the nature of signature staggering.The negative-parity band levels are in good agreement with deformed configuration-mixing shell model (DCM) calculations.

  14. Gamma beam industrial applications at ELI-NP

    Science.gov (United States)

    Suliman, Gabriel; Iancu, Violeta; Ur, Calin A.; Iovea, Mihai; Daito, Izuru; Ohgaki, Hideaki

    2016-09-01

    The Nuclear Physics oriented pillar of the pan-European Extreme Light Infrastructure (ELI-NP) will host an ultra-bright, energy tunable, and quasi-monochromatic gamma-ray beam system in the range of 0.2-19.5 MeV produced by laser Compton backscattering. This gamma beam satisfies the criteria for large-size product investigations with added capabilities like isotope detection through the use of nuclear resonance fluorescence (NRF) and is ideal for non-destructive testing applications. Two major applications of gamma beams are being envisaged at ELI-NP: industrial applications based on NRF and industrial radiography and tomography. Both applications exploit the unique characteristics of the gamma beam to deliver new opportunities for the industry. Here, we present the experimental setups proposed at ELI-NP and discuss their performance based on analytical calculations and GEANT4 numerical simulations. One of the main advantages of using the gamma beam at ELI-NP for applications based on NRF is the availability of an advanced detector array, which can enhance the advantages already provided by the high quality of the gamma beam.

  15. Role of monochromatic light on daily variation of clock gene expression in the pineal gland of chick.

    Science.gov (United States)

    Jiang, Nan; Wang, Zixu; Cao, Jing; Dong, Yulan; Chen, Yaoxing

    2016-11-01

    The avian pineal gland is a master clock that can receive external photic cues and translate them into output rhythms. To clarify whether a shift in light wavelength can influence the circadian expression in chick pineal gland, a total of 240 Arbor Acre male broilers were exposed to white light (WL), red light (RL), green light (GL) or blue light (BL). After 2weeks light illumination, circadian expressions of seven core clock genes in pineal gland and the level of melatonin in plasma were examined. The results showed after illumination with monochromatic light, 24h profiles of all clock gene mRNAs retained circadian oscillation, except that RL tended to disrupt the rhythm of cCry2. Compared to WL, BL advanced the acrophases of the negative elements (cCry1, cCry2, cPer2 and cPer3) by 0.1-1.5h and delayed those of positive elements (cClock, cBmal1 and cBmal2) by 0.2-0.8h. And, RL advanced all clock genes except cClock and cPer2 by 0.3-2.1h, while GL delayed all clock genes by 0.5-1.5h except cBmal2. Meanwhile, GL increased the amplitude and mesor of positive and reduced both parameters of negative clock genes, but RL showed the opposite pattern. Although the acrophase of plasma melatonin was advanced by both GL and RL, the melatonin level was significantly increased in GL and decreased in RL. This tendency was consistent with the variations in the positive clock gene mRNA levels under monochromatic light and contrasted with those of negative clock genes. Therefore, we speculate that GL may enhance positive clock genes expression, leading to melatonin synthesis, whereas RL may enhance negative genes expression, suppressing melatonin synthesis. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Effects of monochromatic light sources on sex hormone levels in serum and on semen quality of ganders.

    Science.gov (United States)

    Chang, Shen-Chang; Zhuang, Zi-Xuan; Lin, Min-Jung; Cheng, Chuen-Yu; Lin, Tsung-Yi; Jea, Yu-Shine; Huang, San-Yuan

    2016-04-01

    Light is an essential external factor influencing various physiological processes, including reproductive performance, in birds. Although several attempts have been made to understand the effect of light on poultry production, the effect of light of a particular wavelength (color) on the reproductive function in geese remains unclear. This study evaluated the effect of various monochromatic light sources on the levels of sex hormone and on semen quality of ganders. Of 30 male White Roman geese in their third reproductive season (average age=3 years), 27 were divided into three groups receiving monochromatic white or red or blue lights. The birds were kept in an environmentally controlled house with a lighting photoperiod of 7L:17D for six weeks as the adaptation period. The photoperiod was subsequently changed to 9L:15D and maintained for 24 weeks. Three ganders at the beginning of the study and three from each group at the end of the adjusting period and the 20th and 30th week of the study period were sacrificed, and their testes and blood samples were collected for determining the sex hormone levels. Semen samples were collected for determining semen quality parameters, including the semen collection index, sperm concentration, semen volume, sperm motility, sperm viability, sperm morphology, and semen quality factor. The results showed that the testosterone and estradiol levels remained unchanged in all three groups at all time points. The ratio of testosterone to estradiol of ganders exposed to white light was significantly higher than that of ganders exposed to red light at the 30th week (Plight were significantly the lowest (Plight were the highest (Plight may maintain a better semen quality than that with red or blue lights in ganders.

  17. Dual Energy CT (DECT Monochromatic Imaging: Added Value of Adaptive Statistical Iterative Reconstructions (ASIR in Portal Venography.

    Directory of Open Access Journals (Sweden)

    Liqin Zhao

    Full Text Available To investigate the effect of the adaptive statistical iterative reconstructions (ASIR on image quality in portal venography by dual energy CT (DECT imaging.DECT scans of 45 cirrhotic patients obtained in the portal venous phase were analyzed. Monochromatic images at 70keV were reconstructed with the following 4 ASIR percentages: 0%, 30%, 50%, and 70%. The image noise (IN (standard deviation, SD of portal vein (PV, the contrast-to-noise-ratio (CNR, and the subjective score for the sharpness of PV boundaries, and the diagnostic acceptability (DA were obtained. The IN, CNR, and the subjective scores were compared among the four ASIR groups.The IN (in HU of PV (10.05±3.14, 9.23±3.05, 8.44±2.95 and 7.83±2.90 decreased and CNR values of PV (8.04±3.32, 8.95±3.63, 9.80±4.12 and 10.74±4.73 increased with the increase in ASIR percentage (0%, 30%, 50%, and 70%, respectively, and were statistically different for the 4 ASIR groups (p<0.05. The subjective scores showed that the sharpness of portal vein boundaries (3.13±0.59, 2.82±0.44, 2.73±0.54 and 2.07±0.54 decreased with higher ASIR percentages (p<0.05. The subjective diagnostic acceptability was highest at 30% ASIR (p<0.05.30% ASIR addition in DECT portal venography could improve the 70 keV monochromatic image quality.

  18. Nonlinear images of scatterers in chirped pulsed laser beams

    Institute of Scientific and Technical Information of China (English)

    Hu Yong-Hua; Wang You-Wen; Wen Shuang-Chun; Fan Dian-Yuan

    2010-01-01

    The bandwidth and the duration of incident pulsed beam are proved to play important roles in modifying the nonlinear image of amplitude-type scatterer.It is found that the initially positive chirp-type bandwidth can suppress the nonlinear image,while the negative one can enhance it,and that both effects are inversely proportional to the incident pulse duration.Numerical simulations further demonstrate that the location of nonlinear image is at the conjugate plane of the scatterer and that,for negatively pre-chirped pulsed beam,the nonlinear image peak intensity can be higher than that in the corresponding monochromatic case under certain conditions.Moreover the effect of group velocity dispersion on nonlinear image is found to be similar to that of chirp-type bandwidth.

  19. Very small beam-size measurement by a reflective synchrotron radiation interferometer

    Directory of Open Access Journals (Sweden)

    T. Naito

    2006-12-01

    Full Text Available A synchrotron radiation (SR interferometer with Herschelian reflective optics has been developed for the measurement of beams of several μm in size. In a conventional refractive SR interferometer, the dispersion effect of the objective lens limits the instrument to a smaller range of beam-size measurements. To avoid this problem, we designed a Herschelian arrangement of reflective optics for the interferometer. The effectiveness of the reflective SR interferometer was confirmed at the KEK Accelerator Test Facility (ATF damping ring. The measured vertical beam size obtained using the reflective SR interferometer was 4.7   μm and the estimated vertical emittance was 0.97×10^{-11}   m.

  20. Improvement of the tuneable monochromatic gamma-ray source at the 15 MeV linac of the University of Gent

    Science.gov (United States)

    Masschaele, B.; Jolie, J.; Mondelaers, W.; Materna, T.; Cauwels, P.; Dierick, M.

    2001-07-01

    It is shown how the tuneable gamma-ray source based on a bremsstrahlung source and a crystal, diffracting in Cauchois geometry, can be made intense and monochromatic using an asymmetrically cut Si crystal. The results and implications are here presented.

  1. Effect of monochromatic light stimuli during embryogenesis on muscular growth, chemical composition, and meat quality of breast muscle in male broilers.

    Science.gov (United States)

    Zhang, L; Zhang, H J; Qiao, X; Yue, H Y; Wu, S G; Yao, J H; Qi, G H

    2012-04-01

    This study was conducted to evaluate the effect of monochromatic light stimuli during embryogenesis on breast muscle growth, chemical composition, and meat quality of male broilers. Fertile broiler eggs (Arbor Acres; n = 1,320) were preweighed and randomly assigned to 1 of 3 treatment groups in 3 modified incubators: 1) control group (in dark condition), 2) monochromatic green light group (560 nm), and 3) monochromatic blue light group (480 nm). The monochromatic lighting systems sourced from light-emitting diode lamps and were equalized at the intensity of 15 lx at eggshell level. After hatch, 120 male chicks from each group were placed in 6 replicates with 20 birds each. All of the birds were housed under white light (30 lx at bird-head level) with a light schedule of 23L:1D. At 21, 35, and 42 d of age, BW and breast muscle weight in the green light group were significantly increased compared with birds in the blue or dark groups (P dark condition or blue group at 42 d of market age (P dark condition (P 0.05). Green light stimuli tended to increase cooking loss (P = 0.08) and L* value of 24-h meat color (P = 0.09). These results suggest that green light stimuli during embryogenesis enhanced the posthatch BW of male broilers, increased breast muscle growth, and improved the feed conversion ratio, but it did not cause any noticeable changes in breast chemical composition or overall meat quality characteristics.

  2. Sensitivity and specificity of monochromatic photography of the ocular fundus in differentiating optic nerve head drusen and optic disc oedema: optic disc drusen and oedema.

    Science.gov (United States)

    Gili, Pablo; Flores-Rodríguez, Patricia; Yangüela, Julio; Orduña-Azcona, Javier; Martín-Ríos, María Dolores

    2013-03-01

    Evaluation of the efficacy of monochromatic photography of the ocular fundus in differentiating optic nerve head drusen (ONHD) and optic disc oedema (ODE). Sixty-six patients with ONHD, 31 patients with ODE and 70 healthy subjects were studied. Colour and monochromatic fundus photography with different filters (green, red and autofluorescence) were performed. The results were analysed blindly by two observers. The sensitivity, specificity and interobserver agreement (k) of each test were assessed. Colour photography offers 65.5 % sensitivity and 100 % specificity for the diagnosis of ONHD. Monochromatic photography improves sensitivity and specificity and provides similar results: green filter (71.20 % sensitivity, 96.70 % specificity), red filter (80.30 % sensitivity, 96.80 % specificity), and autofluorescence technique (87.8 % sensitivity, 100 % specificity). The interobserver agreement was good with all techniques used: autofluorescence (k = 0.957), green filter (k = 0.897), red filter (k = 0.818) and colour (k = 0.809). Monochromatic fundus photography permits ONHD and ODE to be differentiated, with good sensitivity and very high specificity. The best results were obtained with autofluorescence and red filter study.

  3. The X-Ray Beam Imager for Transversal Profiling of Low-Emittance Electron Beam at the SPring-8

    CERN Document Server

    Takano, S; Ohkuma, H

    2005-01-01

    We have developed the X-ray beam imager (XBI) at the accelerator diagnostics beamline I of the SPring-8 to observe transverse profiles of small electron beam of a low-emittance synchrotron light source. The XBI is based on a single Fresnel zone plate (FZP) and an X-ray zooming tube (XZT). The electron beam moving in a bending magnet is imaged by the FZP. Monochromatic X-ray is selected by a double crystal monochromator to avoid the effect of chromatic aberration of the FZP. The X-ray images of the electron beam obtained are converted by the XZT to enlarged images in visible light. The XBI has achieved a superior 1 σ spatial resolution in the micron range, and a fast time resolution of 1 ms. It has also realized a vignetting-free field of view larger than 1.5 mm in diameter on the coordinates of the electron beam, which is not easily obtained by imaging optics using two FZPs. With the XBI, we have successfully measured the profiles of the small electron beam having low vertical emittance in the pm ra...

  4. Dividing a light beam into two beams of orthogonal polarizations by reflection and refraction at a dielectric surface.

    Science.gov (United States)

    Azzam, R M A

    2006-05-15

    Reflection and refraction of monochromatic light by an air-dielectric interface at an incidence angle below the Brewster angle can generate split beams of equal power and orthogonal polarizations under certain achievable conditions. Generation of photon streams of orthogonal polarizations, previously thought to be possible mainly by double refraction in anisotropic crystals, is achieved for an infinite set of input states that leads to a correspondingly infinite set of pairs of orthogonal output states. A bare substrate of PbTe is particularly suitable for this beam splitting function in the IR. However, use of a high-refractive-index quarter-wave layer on a low-refractive-index substrate extends the operating range of this interesting device to a much wider spectral range including the visible.

  5. /sup 87/Sr//sup 86/Sr ratios for basalt from Loihi Seamount, Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    Lanphere, M. (Geological Survey, Menlo Park, CA (USA))

    1983-12-01

    /sup 87/Sr//sup 86/Sr ratios of 15 samples of basalt dredged from Loihi Seamount range from 0.70334 to 0.70368. The basalt types range from tholeiite to basanite in composition and can be divided into six groups on the basis of abundances of K/sub 2/O, Na/sub 2/O, Rb and Sr and /sup 87/Sr//sup 86/Sr ratio. The isotopic data require that the various basalt types be derived from source regions differing in Sr isotopic composition. The Loihi basalts may be produced by mixing of isotopically distinct sources, but the tholeiites and alkalic basalts from Loihi do not show a well-developed inverse trend between Rb/Sr and /sup 87/Sr//sup 86/Sr that is characteristic of the later stages of Hawaiian volcanoes such as Haleakala and Koolau.

  6. Origins of invasive piscivores determined from the strontium isotope ratio (87Sr/86Sr) of otoliths

    Science.gov (United States)

    Wolff, Brian A.; Johnson, Brett M.; Breton, Andre R.; Martinez, Patrick J.; Winkelman, Dana L.; Gillanders, Bronwyn

    2012-01-01

    We examined strontium isotope ratios (87Sr/86Sr) in fish otoliths to determine the origins of invasive piscivores in the Upper Colorado River Basin (UCRB, western USA). We examined 87Sr/86Sr from fishes in different reservoirs, as well as the temporal stability and interspecies variability of 87Sr/86Sr of fishes within reservoirs, determined if 87Sr/86Sr would be useful for "fingerprinting" reservoirs where invasive piscivores may have been escaping into riverine habitat of endangered fishes in the UCRB, and looked for evidence that such movement was occurring. Our results showed that in most cases 87Sr/86Sr was unique among reservoirs, overlapped among species in a given reservoir, and was temporally stable across years. We identified the likely reservoir of origin of river-caught fish in some cases, and we were also able to determine the year of possible escapement. The approach allowed us to precisely describe the 87Sr/86Sr fingerprint of reservoir fishes, trace likely origins of immigrant river fish, and exclude potential sources, enabling managers to focus control efforts more efficiently. Our results demonstrate the potential utility of 87Sr/86Sr as a site-specific and temporally stable marker for reservoir fish and its promise for tracking fish movements of invasive fishes in river-reservoir systems.

  7. Experimental study of ultrasonic beam sectors for energy conversion into Lamb waves and Rayleigh waves.

    Science.gov (United States)

    Declercq, Nico Felicien

    2014-02-01

    When a bounded beam is incident on an immersed plate Lamb waves or Rayleigh waves can be generated. Because the amplitude of a bounded beam is not constant along its wave front, a specific beam profile is formed that influences the local efficiency of energy conversion of incident sound into Lamb waves or Rayleigh waves. Understanding this phenomenon is important for ultrasonic immersion experiments of objects because the quality of such experiments highly depends on the amount of energy transmitted into the object. This paper shows by means of experiments based on monochromatic Schlieren photography that the area within the bounded beam responsible for Lamb wave generation differs from that responsible for Rayleigh wave generation. Furthermore it provides experimental verification of an earlier numerical study concerning Rayleigh wave generation.

  8. Investigation of fingerprints for small polar molecules by using a tunable monochromatic THz source

    Science.gov (United States)

    Sun, Hongqian

    Over the past 20 years, considerable efforts have been dedicated to the generation and the application of electromagnetic waves in the Terahertz (THz) regime. Among all of the proposed applications, the THz spectroscopy is probably the most mature and promising one. According to the previous reports, the THz spectroscopy has been extensively applied into many analysis fields, including the investigation of vibrational modes for the crystalline solids, the characterization of electron transport in the condense matters and the identification of explosive materials at a standoff distance. More interestingly, since most gas phase chemicals exhibit unique transition peaks in the THz spectra, one could in principle achieve highly accurate molecular fingerprinting and chemical sensing as well. However, all of the practical THz spectroscopy applications were still greatly hampered by the lack of suitable sources and detectors. In this thesis, a unique approach to measure the THz spectrum is developed based on a novel tunable narrowband source. Unlike the previous THz systems, high power THz pulses were generated by the difference frequency generation processes between two collinearly propagated near infrared laser beams. To tune the output THz signal frequency, one can simply adjust one of the incident beam frequencies. Therefore, based on a convenient wavelength tuning scheme, the transmission spectra can be measured for a series of polar gases with either similar or distinct molecular structures. According to the measured spectra, it is found that the obtained transition frequencies, absorption intensities and molecular constants are all in good agreement with the theoretical results tabulated in the molecular spectroscopic databases, such as the HITRAN database. By further analyzing the transition frequencies, it is also discovered that one can confidently identify each polar molecule and differentiate between various isotopic variants based on their characteristic

  9. Experimental test of a newly developed single-moderator, multi-detector, directional neutron spectrometer in reference monochromatic fields from 144 keV to 16.5 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Bedogni, R., E-mail: roberto.bedogni@lnf.infn.it [INFN – LNF, via E. Fermi n. 40, 00044 Frascati (Roma) (Italy); Gómez-Ros, J.M. [INFN – LNF, via E. Fermi n. 40, 00044 Frascati (Roma) (Italy); CIEMAT, Av. Complutense 40, 28040 Madrid (Spain); Pola, A.; Bortot, D. [Politecnico di Milano, Dipartimento di Energia, via La Masa 34, 20156 Milano (Italy); INFN – Milano, Via Celoria 16, 20133 Milano (Italy); Gentile, A. [INFN – LNF, via E. Fermi n. 40, 00044 Frascati (Roma) (Italy); Introini, M.V. [Politecnico di Milano, Dipartimento di Energia, via La Masa 34, 20156 Milano (Italy); INFN – Milano, Via Celoria 16, 20133 Milano (Italy); Buonomo, B. [INFN – LNF, via E. Fermi n. 40, 00044 Frascati (Roma) (Italy); Lorenzoli, M. [Politecnico di Milano, Dipartimento di Energia, via La Masa 34, 20156 Milano (Italy); INFN – Milano, Via Celoria 16, 20133 Milano (Italy); Mazzitelli, M. [INFN – LNF, via E. Fermi n. 40, 00044 Frascati (Roma) (Italy); Sacco, D. [INFN – LNF, via E. Fermi n. 40, 00044 Frascati (Roma) (Italy); INAIL – DPIA, Via di Fontana Candida n.1, 00040 Monteporzio Catone (Italy)

    2015-05-11

    A new directional neutron spectrometer called CYSP (CYlindrical SPectrometer) was developed within the NESCOFI@BTF (2011–2013) collaboration. The device, composed by seven active thermal neutron detectors located along the axis of a cylindrical moderator, was designed to simultaneously respond from the thermal domain up to hundreds of MeV neutrons. The new spectrometer condenses the performance of the Bonner Sphere Spectrometer in a single moderator; thus requiring only one exposure to determine the whole spectrum. The CYSP response matrix, determined with MCNP, has been experimentally evaluated with monochromatic reference neutron fields from 144 keV to 16.5 MeV, plus a {sup 252}Cf source, available at NPL (Teddington, UK). The results of the experiment confirmed the correctness of the response matrix within an overall uncertainty of ±2.5%. The new active spectrometer CYSP offers an innovative option for real-time monitoring of directional neutron fields as those produced in neutron beam-lines.

  10. Scheme for generation of highly monochromatic X-rays from a baseline XFEL undulator

    CERN Document Server

    Geloni, Gianluca; Saldin, Evgeni

    2010-01-01

    One goal of XFEL facilities is the production of narrow bandwidth X-ray radiation. The self-seeding scheme was proposed to obtain a bandwidth narrower than that achievable with conventional X-ray SASE FELs. A self-seeded FEL is composed of two undulators separated by a monochromator and an electron beam bypass that must compensate for the path delay of X-rays in the monochromator. This leads to a long bypass, with a length in the order of 40-60 m, which requires modifications of the baseline undulator configuration. As an attempt to get around this obstacle, together with a study of the self-seeding scheme for the European XFEL, here we propose a novel technique based on a pulse doubler concept. Using a crystal monochromator installed within a short magnetic chicane in the baseline undulator, it is possible to decrease the bandwidth of the radiation well beyond the XFEL design down to 10^(-5). The magnetic chicane can be installed without any perturbation of the XFEL focusing structure, and does not interfere...

  11. Milli-electronvolt monochromatization of hard X-rays with a sapphire backscattering monochromator

    Science.gov (United States)

    Sergueev, I.; Wille, H.-C.; Hermann, R. P.; Bessas, D.; Shvyd’ko, Yu. V.; Zając, M.; Rüffer, R.

    2011-01-01

    A sapphire backscattering monochromator with 1.1 (1) meV bandwidth for hard X-rays (20–40 keV) is reported. The optical quality of several sapphire crystals has been studied and the best crystal was chosen to work as the monochromator. The small energy bandwidth has been obtained by decreasing the crystal volume impinged upon by the beam and by choosing the crystal part with the best quality. The monochromator was tested at the energies of the nuclear resonances of 121Sb at 37.13 keV, 125Te at 35.49 keV, 119Sn at 23.88 keV, 149Sm at 22.50 keV and 151Eu at 21.54 keV. For each energy, specific reflections with sapphire temperatures in the 150–300 K region were chosen. Applications to nuclear inelastic scattering with these isotopes are demonstrated. PMID:21862862

  12. Creating Ruddlesden-Popper phases by hybrid molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Haislmaier, Ryan C.; Stone, Greg; Alem, Nasim; Engel-Herbert, Roman, E-mail: rue2@psu.edu [Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2016-07-25

    The synthesis of a 50 unit cell thick n = 4 Sr{sub n+1}Ti{sub n}O{sub 3n+1} (Sr{sub 5}Ti{sub 4}O{sub 13}) Ruddlesden-Popper (RP) phase film is demonstrated by sequentially depositing SrO and TiO{sub 2} layers in an alternating fashion using hybrid molecular beam epitaxy (MBE), where Ti was supplied using titanium tetraisopropoxide (TTIP). A detailed calibration procedure is outlined for determining the shuttering times to deposit SrO and TiO{sub 2} layers with precise monolayer doses using in-situ reflection high energy electron diffraction (RHEED) as feedback. Using optimized Sr and TTIP shuttering times, a fully automated growth of the n = 4 RP phase was carried out over a period of >4.5 h. Very stable RHEED intensity oscillations were observed over the entire growth period. The structural characterization by X-ray diffraction and high resolution transmission electron microscopy revealed that a constant periodicity of four SrTiO{sub 3} perovskite unit cell blocks separating the double SrO rocksalt layer was maintained throughout the entire film thickness with a very little amount of planar faults oriented perpendicular to the growth front direction. These results illustrate that hybrid MBE is capable of layer-by-layer growth with atomic level precision and excellent flux stability.

  13. Visible-light beam size monitors using synchrotron radiation at CESR

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.T., E-mail: sw565@cornell.edu [Cornell Laboratory for Accelerator-Based Science and Education, Cornell University, Ithaca, NY 14853 (United States); Rubin, D.L.; Conway, J.; Palmer, M.; Hartill, D. [Cornell Laboratory for Accelerator-Based Science and Education, Cornell University, Ithaca, NY 14853 (United States); Campbell, R.; Holtzapple, R. [Physics Department, California Polytechnic State University, San Luis Obispo, CA 93407 (United States)

    2013-03-01

    A beam profile monitor utilizing visible synchrotron radiation (SR) from a bending magnet has been designed and installed in Cornell Electron-Positron Storage Ring (CESR). The monitor employs a double-slit interferometer to measure both the horizontal and vertical beam sizes over a wide range of beam currents. By varying the separation of the slits, beam sizes ranging from 50 to 500 μm can be measured with a resolution of approximately 5 μm. To measure larger beam size (>500 μm), direct imaging can be employed by rotating the double slits away from SR beam path. By imaging the π-polarized component of SR, a small vertical beam size (∼70 μm) was measured during an undulator test run in CESR, which was consistent with the interferometer measurement. To measure the bunch length, a beam splitter is inserted to direct a fraction of light into a streak camera setup. This beam size monitor measures the transverse and longitudinal beam sizes simultaneously, which is successfully used for intrabeam scattering studies. Detailed error analysis is discussed.

  14. Shielding calculation for the thickness of the SR facility safety shutter

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The safety shutter of the SR (synchrotron radiation) facility located at the front end of the facility is an indispensable component for radiation protection. Its thickness is decided by the gas bremsstrahlung produced in the SR facility storage ring by the interaction of electrons with the residual gas molecules in the vacuum chamber of the storage ring. In the calculation, the 3.5 GeV, 300mA electron beam and a 15 m long insertion-device straight section (0.133 μPa) were taken into account, and the safety shutter was assumed to be located 12 m away from the end of the straight section. The EGSnrc code based on the Monte-Carlo method and empirical formulas were used, respectively, to calculate the thickness to satisfy the shielding requirement of the safety shutter at the front end of the SR facility, and the results were compared and the availability of EGSnrc was proved.

  15. Room-temperature ferroelectricity of SrTiO{sub 3} films modulated by cation concentration

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Fang; Zhang, Qinghua; Yang, Zhenzhong; Gu, Junxing; Liang, Yan; Li, Wentao; Wang, Weihua [Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Jin, Kuijuan; Gu, Lin; Guo, Jiandong, E-mail: jdguo@iphy.ac.cn [Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China)

    2015-08-24

    The room-temperature ferroelectricity of SrTiO{sub 3} is promising for oxide electronic devices controlled by multiple fields. An effective way to control the ferroelectricity is highly demanded. Here, we show that the off-centered antisite-like defects in SrTiO{sub 3} films epitaxially grown on Si (001) play the determinative role in the emergence of room-temperature ferroelectricity. The density of these defects changes with the film cation concentration sensitively, resulting in a varied coercive field of the ferroelectric behavior. Consequently, the room-temperature ferroelectricity of SrTiO{sub 3} films can be effectively modulated by tuning the temperature of metal sources during the molecular beam epitaxy growth. Such an easy and reliable modulation of the ferroelectricity enables the flexible engineering of multifunctional oxide electronic devices.

  16. Experiences with the determination of Sr-89 and Sr-90 using fast methods; Erfahrungen bei der Bestimmung von {sup 89}Sr und {sup 90}Sr mittels Schnellmethoden

    Energy Technology Data Exchange (ETDEWEB)

    Kowalik, C.; Fueger, J. [Thueringer Landesanstalt fuer Umwelt und Geologie, Jena (Germany). Landesmessstelle fuer Umweltradioaktivaet

    2014-01-20

    Quick methods of the measurement of {sup 89}Sr and {sup 90}Sr have a great importance in the supervision of the environmental radioactivity. It is necessary to receive in short time dependable analytical data to be able to carry out suitable assessments or to give recommendations. The aim of the investigations was to be guaranteed the demands for these methods (test preparation, measurement and evaluation). The use of the solid phase extraction by means of commercial Sr Resin trademark columns (4.4' (5')-Di-tert-butylcyclohexanol-18-kronen-6-aether) (Triskem) to the radiochemical separation of the Sr isotopes was suitable. The measurements occurred to the FHT 770 T12 - Multi Low Level Alpha/Beta Sample Counter (Thermo Scientific). The results contain the summary activities of all available Sr isotopes, as for example {sup 89}Sr and {sup 90}Sr. The calculations of the single activities occur about the mathematical algorithm of the linear development on the basis of the works of G. Kanisch. The first results show, this method is suitable for the analysis of {sup 89}Sr and {sup 90}Sr and is used therefore in future in Thuringia.

  17. Laser synchrotron radiation and beam cooling

    Energy Technology Data Exchange (ETDEWEB)

    Esarey, E.; Sprangle, P.; Ting, A. [Naval Research Lab., Washington, DC (United States)] [and others

    1995-12-31

    The interaction of intense {approx_gt} 10{sup 18} W/cm{sup 2}, short pulse ({approx_lt} 1 ps) lasers with electron beams and plasmas can lead to the generation of harmonic radiation by several mechanisms. Laser synchrotron radiation may provide a practical method for generating tunable, near monochromatic, well collimated, short pulse x-rays in compact, relatively inexpensive source. The mechanism for the generation of laser synchrotron radiation is nonlinear Thomson scattering. Short wavelengths can be generated via Thomson scattering by two methods, (i) backscattering from relativistic electron beams, in which the radiation frequency is upshifted by the relativistic factor 4{gamma}{sup 2}, and (ii) harmonic scattering, in which a multitude of harmonics are generated with harmonic numbers extending out to the critical harmonic number nc{approx_equal}a{sub 0}{sup 3} {much_gt} 1, where a{sub 0} {approx_equal}10{sup -9}{lambda}I{sup 1/2}, {lambda} is the laser wavelength in {mu}m and I is the laser intensity in W/cm{sup 2}. Laser synchrotron sources are capable of generating short ({approx_lt} ps) x-ray pulses with high peak flux ({approx_gt} 10{sup 21} photons/s) and brightness ({approx_gt}{sup 19} photons/s-mm{sup 2}-mrad{sup 2} 0.1%BW. As the electron beam radiates via Thomson scattering, it can subsequently be cooled, i.e., the beam emittance and energy spread can be reduced. This cooling can occur on rapid ({approximately} ps) time scales. In addition, electron distributions with sufficiently small axial energy spreads can be used to generate coherent XUV radiation via a laser-pumped FEL mechanism.

  18. Light-dependent magnetoreception in birds: increasing intensity of monochromatic light changes the nature of the response

    Directory of Open Access Journals (Sweden)

    Bischof Hans-Joachim

    2007-02-01

    Full Text Available Abstract Background The Radical Pair model proposes that magnetoreception is a light-dependent process. Under low monochromatic light from the short-wavelength part of the visual spectrum, migratory birds show orientation in their migratory direction. Under monochromatic light of higher intensity, however, they showed unusual preferences for other directions or axial preferences. To determine whether or not these responses are still controlled by the respective light regimes, European robins, Erithacus rubecula, were tested under UV, Blue, Turquoise and Green light at increasing intensities, with orientation in migratory direction serving as a criterion whether or not magnetoreception works in the normal way. Results The birds were well oriented in their seasonally appropriate migratory direction under 424 nm Blue, 502 nm Turquoise and 565 nm Green light of low intensity with a quantal flux of 8·1015 quanta s-1 m-2, indicating unimpaired magnetoreception. Under 373 nm UV of the same quantal flux, they were not oriented in migratory direction, showing a preference for the east-west axis instead, but they were well oriented in migratory direction under UV of lower intensity. Intensities of above 36·1015 quanta s-1 m-2 of Blue, Turquoise and Green light elicited a variety of responses: disorientation, headings along the east-west axis, headings along the north-south axis or 'fixed' direction tendencies. These responses changed as the intensity was increased from 36·1015 quanta s-1 m-2 to 54 and 72·1015 quanta s-1 m-2. Conclusion The specific manifestation of responses in directions other than the migratory direction clearly depends on the ambient light regime. This implies that even when the mechanisms normally providing magnetic compass information seem disrupted, processes that are activated by light still control the behavior. It suggests complex interactions between different types of receptors, magnetic and visual. The nature of the

  19. Colliding. gamma. e- and. gamma gamma. -beams on the basis of electron-positron linear colliders

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, I.F.; Kotkin, G.L.; Serbo, V.G.; Tel' nov, V.I.

    1983-08-01

    Main properties of the ..gamma..e and ..gamma gamma.. collisions are discussed in some detail with application to the generation of colliding ..gamma..e and ..gamma gamma.. beams basing on the designed linear accelerators with colliding e/sup +/e/sup -/ beams, VLEEP and SLC, as it was proposed in a previous work. Intensive ..gamma.. beams with the energy 50 GeV would be produced from scattering of the laser light focused to the electron beams of the accelerators. Laser radiation is focused to the electron beam in the conversion region at a distance of about 10 cm from the place of collision. After scattering on electrons high-energy photons move practically along the electron primary trajectories and are focused in the collision region. The electrons are deflected from the collision region by means of approximately 1 T magnetic field. Then the produced ..gamma..-beam collides with an electron beam or a similar ..gamma..-beam. In the case when the maximum luminosity (L) is attained, the luminosity distribution in the invariant mass of the ..gamma..e or ..gamma gamma.. systems is wide. A monochromatization of the collisions up to the level of 5-10% is possible. That will entail a decrease in the luminosity, the procedure is most effective if one uses the electrons and the laser photons with opposite helicities. Examples of physically interesting problems to be investigated with the proposed ..gamma..e and ..gamma gamma.. beams are suggested.

  20. X-ray beam monitor made by thin-film CVD single-crystal diamond.

    Science.gov (United States)

    Marinelli, Marco; Milani, E; Prestopino, G; Verona, C; Verona-Rinati, G; Angelone, M; Pillon, M; Kachkanov, V; Tartoni, N; Benetti, M; Cannatà, D; Di Pietrantonio, F

    2012-11-01

    A novel beam position monitor, operated at zero bias voltage, based on high-quality chemical-vapor-deposition single-crystal Schottky diamond for use under intense synchrotron X-ray beams was fabricated and tested. The total thickness of the diamond thin-film beam monitor is about 60 µm. The diamond beam monitor was inserted in the B16 beamline of the Diamond Light Source synchrotron in Harwell (UK). The device was characterized under monochromatic high-flux X-ray beams from 6 to 20 keV and a micro-focused 10 keV beam with a spot size of approximately 2 µm × 3 µm square. Time response, linearity and position sensitivity were investigated. Device response uniformity was measured by a raster scan of the diamond surface with the micro-focused beam. Transmissivity and spectral responsivity versus beam energy were also measured, showing excellent performance of the new thin-film single-crystal diamond beam monitor.

  1. Effect of Wood Aging on Wine Mineral Composition and (87)Sr/(86)Sr Isotopic Ratio.

    Science.gov (United States)

    Kaya, Ayse D; Bruno de Sousa, Raúl; Curvelo-Garcia, António S; Ricardo-da-Silva, Jorge M; Catarino, Sofia

    2017-06-14

    The evolution of mineral composition and wine strontium isotopic ratio (87)Sr/(86)Sr (Sr IR) during wood aging were investigated. A red wine was aged in stainless steel tanks with French oak staves (Quercus sessiliflora Salisb.), with three industrial scale replicates. Sampling was carried out after 30, 60, and 90 days of aging, and the wines were evaluated in terms of general analysis, phenolic composition, total polysaccharides, multielement composition, and Sr IR. Li, Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, and Pb elements and (87)Sr/(86)Sr were determined by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and Na, K, Ca, and Fe by flame atomic absorption spectrometry (FAAS). Two-way ANOVA was applied to assess wood aging and time effect on Sr IR and mineral composition. Wood aging resulted in significantly higher concentrations of Mg, V, Co, Ni, and Sr. At the end of the aging period, wine exhibited statistically identical Sr IR compared to control. Study suggests that wood aging does not affect (87)Sr/(86)Sr, not precluding the use of this parameter for wine traceability purposes.

  2. Brain responses to violet, blue, and green monochromatic light exposures in humans: prominent role of blue light and the brainstem.

    Directory of Open Access Journals (Sweden)

    Gilles Vandewalle

    Full Text Available BACKGROUND: Relatively long duration retinal light exposure elicits nonvisual responses in humans, including modulation of alertness and cognition. These responses are thought to be mediated in part by melanopsin-expressing retinal ganglion cells which are more sensitive to blue light than violet or green light. The contribution of the melanopsin system and the brain mechanisms involved in the establishment of such responses to light remain to be established. METHODOLOGY/PRINCIPAL FINDINGS: We exposed 15 participants to short duration (50 s monochromatic violet (430 nm, blue (473 nm, and green (527 nm light exposures of equal photon flux (10(13ph/cm(2/s while they were performing a working memory task in fMRI. At light onset, blue light, as compared to green light, increased activity in the left hippocampus, left thalamus, and right amygdala. During the task, blue light, as compared to violet light, increased activity in the left middle frontal gyrus, left thalamus and a bilateral area of the brainstem consistent with activation of the locus coeruleus. CONCLUSION/SIGNIFICANCE: These results support a prominent contribution of melanopsin-expressing retinal ganglion cells to brain responses to light within the very first seconds of an exposure. The results also demonstrate the implication of the brainstem in mediating these responses in humans and speak for a broad involvement of light in the regulation of brain function.

  3. Computer simulations on resonant fluorescence spectra in atomic gases in two monochromatic laser fields of arbitrary intensity and magnetic field

    Science.gov (United States)

    Karagodova, Tamara Y.

    1996-03-01

    In the intense radiation fields with power density from 104W/cm2 to 109W/cm2 the essential modification of electronic states of atoms occurs displaying, in particular, in modifications of resonant fluorescence (rf) spectra. We use 'Fermi golden rule' for calculations of relative intensities and frequencies for rf multiplet for real multilevel initially unexcited atoms in two monochromatic laser fields of arbitrary intensity resonant to adjacent transitions of (Xi) or (Lambda) types and magnetic field, giving the level splittings of different values from Zeeman to Paschen-Back effect. The dependence of quasienergies on parameters obtained with the help of a sorting program permits us to define the values of parameters for which the states of the system are mixed and so to receive the correct probability amplitudes for instantaneous or adiabatic regimes of switching the perturbation. The analysis of the quasienergies and form of rf spectra permits us to get relations between the form of the spectra and modifications of electronic structure of the atom due to radiation fields and external magnetic field.

  4. Spitzer Analysis of HII Region Complexes in the Magellanic Clouds: Determining a Suitable Monochromatic Obscured Star Formation Indicator

    CERN Document Server

    Lawton, Brandon; Babler, Brian; Block, Miwa; Bolatto, Alberto D; Bracker, Steve; Carlson, Lynn R; Engelbracht, Charles W; Hora, Joseph L; Indebetouw, Remy; Madden, Suzanne C; Meade, Marilyn; Meixner, Margaret; Misselt, Karl; Oey, M S; Oliveira, Joana M; Robitaille, Thomas; Sewilo, Marta; Shiao, Bernie; Vijh, Uma P; Whitney, Barbara

    2010-01-01

    HII regions are the birth places of stars, and as such they provide the best measure of current star formation rates (SFRs) in galaxies. The close proximity of the Magellanic Clouds allows us to probe the nature of these star forming regions at small spatial scales. We aim to determine the monochromatic IR band that most accurately traces the bolometric IR flux (TIR), which can then be used to estimate an obscured SFR. We present the spatial analysis, via aperture/annulus photometry, of 16 LMC and 16 SMC HII region complexes using the Spitzer IRAC and MIPS bands. UV rocket data and SHASSA H-alpha data are also included. We find that nearly all of the LMC and SMC HII region SEDs peak around 70um, from ~10 to ~400 pc from the central sources. As a result, the sizes of HII regions as probed by 70um is approximately equal to the sizes as probed by TIR (about 70 pc in radius); the radial profile of the 70um flux, normalized by TIR, is constant at all radii (70um ~ 0.45 TIR); the 1-sigma standard deviation of the 7...

  5. Successful treatment with 308-nm monochromatic excimer light and subsequent tacrolimus 0.03% ointment in refractory plasma cell cheilitis.

    Science.gov (United States)

    Yoshimura, Kazuhiro; Nakano, Shunji; Tsuruta, Daisuke; Ohata, Chika; Hashimoto, Takashi

    2013-06-01

    Plasma cell cheilitis is a chronic inflammatory disease that presents with erythema, erosions, ulcers and occasional nodules within the mucosa, including the lips. It is histopathologically characterized by dense plasma cell infiltration in the lamina propria of the mucous membranes. Several treatments for plasma cell cheilitis have been reported, including topical steroids, topical antibiotics or topical tacrolimus. However, 308-nm monochromatic excimer light (MEL) has never been reported as a treatment option, while it was reported to be very effective in treating erosive oral lichen planus. We report a 62-year-old man who had chronic plasma cell cheilitis on the lower lip, which was refractory to topical and systemic corticosteroid. The lesion and severe pain were significantly improved by the treatment with nine sessions of 308-nm MEL twice per week with a total dose of 1120 mJ/cm(2). However, the lesion gradually worsened after treatment frequency was reduced to once per month. Subsequent tacrolimus 0.03% ointment cleared the lesion completely in a month and no recurrence was observed a year later. Refractory plasma cell cheilitis and concomitant severe pain quickly responded to 308-nm MEL when administrated twice per week. Because the long interval between each MEL treatment seemed ineffective to improve the lesion, appropriate frequency and adequate total dose of MEL treatment may be necessary for a successful treatment.

  6. The Effect of Monochromatic Infrared Photo Energy on the Irritability of Myofascial Trigger Spot of Rabbit Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Ta-Shen Kuan

    2015-01-01

    Full Text Available Objective. To determine whether the vasodilatation effect of monochromatic infrared photo energy (MIRE had the potential for the treatment of myofascial trigger spot (MTrS in rabbits. Design. A randomized-controlled animal study. Subjects. Twelve adult New Zealand rabbits. Methods. For each rabbit, a MTrS (equivalent to a myofascial trigger point in humans in one side of the biceps femoris muscle was randomly selected for MIRE treatment (experimental side, while another MTrS in the other side (control side received a sham treatment. The intervention consisted of a daily 40 minutes treatment, three times per week for 2 weeks. The prevalence of endplate noise (EPN loci in the MTrS was assessed before, immediately after, and one week after the completion of the 2-week treatment. Results. MIRE could suppress the prevalence of EPN in the MTrS. The degree of reduction in EPN prevalence in the MTrS between the experimental side and the control side was significantly different immediately after MIRE treatment, but not significantly different one week after MIRE treatment. Conclusion. Our study suggests that MIRE may be a useful therapeutic option for the management of the myofascial trigger point in humans.

  7. Application of FEL technique for constructing high-intensity, monochromatic, polarized gamma-sources at storage rings

    Energy Technology Data Exchange (ETDEWEB)

    Saldin, E.L.; Schneidmiller, E.A.; Ulyanov, Yu.N. [Automatic Systems Corporation, Samara (Russian Federation)] [and others

    1995-12-31

    A possibility to construct high-intensity tunable monochromatic{gamma}-source at high energy storage rings is discussed. It is proposed to produce {gamma}-quanta by means of Compton backscattering of laser photons on electrons circulating in the storage. The laser light wavelength is chosen in such a way that after the scattering, the electron does not leave the separatrix. So as the probability of the scattering is rather small, energy oscillations are damped prior the next scattering. As a result, the proposed source can operate in {open_quotes}parasitic{close_quote} mode not interfering with the main mode of the storage ring operation. Analysis of parameters of existent storage rings (PETRA, ESRF, Spring-8, etc) shows that the laser light wavelength should be in infrared, {lambda}{approximately} 10 - 400 {mu}m, wavelength band. Installation at storage rings of tunable free-electron lasers with the peak and average output power {approximately} 10 MW and {approximately} 1 kW, respectively, will result in the intensity of the {gamma}-source up to {approximately} 10{sup 14}s{sup -1} with tunable {gamma}-quanta energy from several MeV up to several hundreds MeV. Such a {gamma}-source will reveal unique possibilities for precision investigations in nuclear physics.

  8. Optimization of Kicker Pulse Bump by Using a SR Monitor at the Photon Factory

    CERN Document Server

    Mitsuhashi, Toshiyuki

    2005-01-01

    We plan to operate the Photon Factory storage ring by top-up injection mode from 2006. To realize this operation mode, remaining coherent oscillation of the stored beam due to error in the injection pulse bump is one of most serious problem. To reducing the error in the injection pulse bump, we calibrated kicking angles of the injection kicker magnets by means of the term by term instantaneous observation of beam profile. We have a SR monitor inside of injection pulse bump. By measureing the tern by tern beam position after the excitation of kicker magnet, we can calibrate the kick angle of the kicker magnet. By using this calibration, we optimized injection pulse bump. As a result, we reduced amplitude of remaining coherent oscillation less than 1/4 of the 1??of the beam size.

  9. Visualization and on line monitoring of geometric parameters of beams at KSRS

    CERN Document Server

    Ioudin, L; Potlovsky, K; Rezvov, V

    2001-01-01

    On the basis of developed hardware and software we investigate the opportunity of on line registration of geometric parameters of low intensity SR beam and electron beams in single shot mode. Ionization and luminescence detectors form real optic image of a beam cross section. The image is registered by a TV camera, digitized and processed by a computer. Gray scale image and profiles of a beam are represented. Accumulation and statistic processing of the data give the possibility to increase the sensitivity of the hardware and to calculate the average position of the beam gravity center, dispersion and statistic uncertainty.

  10. Stimulation with monochromatic green light during incubation alters satellite cell mitotic activity and gene expression in relation to embryonic and posthatch muscle growth of broiler chickens.

    Science.gov (United States)

    Zhang, L; Zhang, H J; Wang, J; Wu, S G; Qiao, X; Yue, H Y; Yao, J H; Qi, G H

    2014-01-01

    Previous studies showed that monochromatic green light stimuli during embryogenesis accelerated posthatch body weight (BW) and pectoral muscle growth of broilers. In this experiment, we further investigated the morphological and molecular basis of this phenomenon. Fertile broiler eggs (Arbor Acres, n=880) were pre-weighed and randomly assigned to 1 of the 2 incubation treatment groups: (1) dark condition (control group), and (2) monochromatic green light group (560 nm). The monochromatic lighting systems sourced from light-emitting diode lamps and were equalized at the intensity of 15 lx at eggshell level. The dark condition was set as a commercial control from day 1 until hatching. After hatch, 120 male 1-day-old chicks from each group were housed under incandescent white light with an intensity of 30 lx at bird-head level. No effects of light stimuli during embryogenesis on hatching time, hatchability, hatching weight and bird mortality during the feeding trial period were observed in the present study. Compared with the dark condition, the BW, pectoral muscle weight and myofiber cross-sectional areas were significantly greater on 7-day-old chicks incubated under green light. Green light also increased the satellite cell mitotic activity of pectoral muscle on 1- and 3-day-old birds. In addition, green light upregulated MyoD, myogenin and myostatin mRNA expression in late embryos and/ or newly hatched chicks. These data suggest that stimulation with monochromatic green light during incubation promote muscle growth by enhancing proliferation and differentiation of satellite cells in late embryonic and newly hatched stages. Higher expression of myostatin may ultimately help prevent excessive proliferation and differentiation of satellite cells in birds incubated under green light.

  11. Analysis of monochromatic signals by using data from the detector of Allegro gravitational waves; Analise de sinais monocromaticos utilizando dados do detector de ondas gravitacionais Allegro

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Fernanda Gomes de

    2010-07-01

    The present work is developed in the searching for monochromatic gravitational waves signals in ALLEGRO's data. We have two procedures for data analysis based on the periodogram of Welch, which a method for the detection of monochromatic signals in the middle of noise which basically makes power spectrum estimates using averaged modified periodograms. By using this method it was possible to obtain a power spectrum for the data which reinforce peaks due to monochromatic signals. The two procedures of analysis for the years 1997 and 1999, were focused on monitoring a peak that appears in the spectral density of ALLEGRO's detector, so called 'mystery mode' (near 887 Hz). We look for variations in the frequency of the mystery mode that agree with the variation of the Doppler effect. In the rst analysis we have used by the variation of daily and annual Doppler shift. For the second one, we have only searched annual Doppler shift. We have applied the periodogram of Welch in both tests in the raw data of the detector in the search for a real signal and we found some peaks that can be candidates of gravitational radiation only the second analysis. In order to test the method we used in both analysis a simulated gravitational wave signal modulated by the Doppler effect injected in the data. We detected in both methods the artificial signal of GW simulated. Therefore we have reason to conclude that both methods are efficient in the search for monochromatic signals. (author)

  12. 1D Modeling of a Bifacial Silicon Solar Cell under Frequency Modulation Monochromatic Illumination: Determination of the Equivalent Electrical Circuit Related to the Surface Recombination Velocity

    Directory of Open Access Journals (Sweden)

    H. Ly Diallo

    2012-06-01

    Full Text Available We present in this study the determination of the equivalent electrical circuits associated to the recombination velocities for a bifacial silicon solar cell under frequency modulation and monochromatic illumination. This determination is based on Bode and Nyquist diagrams that is the variations of the phase and the module of the back surface and intrinsic junction recombination velocities. Their dependence on illumination wavelength is also shown.

  13. Local and Systemic Cardiovascular Effects from Monochromatic Infrared Therapy in Patients with Knee Osteoarthritis: A Double-Blind, Randomized, Placebo-Controlled Study

    Directory of Open Access Journals (Sweden)

    Ru-Lan Hsieh

    2012-01-01

    Full Text Available Infrared (IR therapy is used for pain relief in patients with knee osteoarthritis (OA. However, IR’s effects on the cardiovascular system remain uncertain. Therefore, we investigated the local and systemic cardiovascular effects of monochromatic IR therapy on patients with knee OA in a double-blind, randomized, placebo-controlled study. Seventy-one subjects with knee OA received one session of 40 min of active or placebo monochromatic IR treatment (with power output of 6.24 W, wavelength of 890 nm, power density of 34.7 mW/cm2 for 40 min, total energy of 41.6 J/cm2 per knee per session over the knee joints. Heart rate, blood pressure, and knee arterial blood flow velocity were periodically assessed at the baseline, during, and after treatment. Data were analyzed by repeated-measure analysis of covariance. Compared to baseline, there were no statistically significant group x time interaction effects between the 2 groups for heart rate (P=0.160, blood pressure (systolic blood pressure: P=0.861; diastolic blood pressure: P=0.757, or mean arterial blood flow velocity (P=0.769 in follow-up assessments. The present study revealed that although there was no increase of knee arterial blood flow velocity, monochromatic IR therapy produced no detrimental systemic cardiovascular effects.

  14. LIGHT PRESSURE: Theoretical study of the light pressure force acting on a spherical dielectric particle of an arbitrary size in the interference field of two plane monochromatic electromagnetic waves

    Science.gov (United States)

    Guzatov, D. V.; Gaida, L. S.; Afanas'ev, Anatolii A.

    2008-12-01

    The light pressure force acting on a spherical dielectric particle in the interference field of two plane monochromatic electromagnetic waves is studied in detail for different particle radii and angles of incidence of waves.

  15. In the wonderland of ultra-parallel neutron beams

    Indian Academy of Sciences (India)

    Appoorva G Wagh

    2008-10-01

    Bragg reflections from single crystals yield angular widths of a few arcsec for thermal neutron beams. The Bonse-Hart proposal to attain a sharp, nearly rectangular profile by Bragg reflecting neutrons multiply from a channel-cut single crystal, was realized in its totality three and a half decades later by achieving the corresponding Darwin reflection curves for 5.23 Å neutrons. This facilitated SUSANS (Super USANS) measurements in the ∼ 10-5 Å-1 range. The polarized neutron option was introduced into the SUSANS set-up by separating the up- and down-spin neutron beams by ∼ 10 arcsec with a magnetic (air) prism. The neutron angular width has recently been reduced further by an order of magnitude to ∼ 0.6 arcsec by diffracting 5.3 Å neutrons from a judiciously optimized Bragg prism. This constitutes the most parallel monochromatic neutron beam produced to date. I present the first SUSANS spectra probing the ∼ 10-6 Å-1 domain, recorded with this beam.

  16. New accelerators for femtosecond beam pump-and-probe analysis

    Energy Technology Data Exchange (ETDEWEB)

    Uesaka, Mitsuru [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan)]. E-mail: uesaka@utnl.jp; Sakumi, Akira [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Hosokai, Tomonao [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Kinoshita, Kenichi [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Yamaoka, Nobuaki [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Zhidkov, Alexei [National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Ohkubo, Takeru [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Ueda, Toru [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Muroya, Yusa [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Katsumura, Yosuke [Nuclear Engineering Research Laboratory, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Iijima, Hokuto [Japan Atomic Energy Research Institute, 2-4 Shirane, Tokai, Naka, Ibaraki 319-1195 (Japan); Tomizawa, Hiromitsu [Japan Synchrotron Radiation Research InstituteI, 1-1-1 Kouto, Mikazuki-cho, Sayo-gun, Hyogo 679-5198 (Japan); Kumagai, Noritaka [Japan Synchrotron Radiation Research InstituteI, 1-1-1 Kouto, Mikazuki-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2005-12-15

    Femtosecond electron beams are novel tool for pump-probe analysis of condensed matter. Progress in developing femtosecond electron beams with the use of both conventional accelerators and laser-plasma accelerators is discussed. In conventional accelerators, the critical issue is timing jitter and drift of the linac-laser synchronization system. Sophisticated electronic devices are developed to reduce the jitter to 330 fs (rms); the precise control of temperature at several parts of the accelerator lessens the drift to 1 ps (rms). We also report on a full-optical X-ray and e-beam system based on the laser-plasma cathode by using a 12 TW 50 fs laser, which enables 40 MeV (at maximum), 40 fs (cal.), 100 pC and quasi-monochromatic single electron bunches. Since the synchronization is done by a passive optical beam-splitter, this system intrinsically has no jitter and drift. It could achieve tens of femtoseconds time-resolved analysis in the near future.

  17. Coherence vortices of partially coherent beams in the far field

    Institute of Scientific and Technical Information of China (English)

    Liu Pu-Sheng; Lü Bai-da

    2007-01-01

    Based on the propagation law of cross-spectral density function, studied in this paper are the coherence vortices of partially coherent, quasi-monochromatic singular beams with Gaussian envelope and Schell-model correlator in the far field, where our main attention is paid to the evolution of far-field coherence vortices into intensity vortices of fully coherent beams. The results show that, although there are usually no zeros of intensity in partially coherent beams with Gaussian envelope and Schell-model correlator, zeros of spectral degree of coherence exist. The coherence vortices of spectral degree of coherence depend on the relative coherence length, mode index and positions of pairs of points.If a point and mode index are kept fixed, the position of coherence vortices changes with the increase of the relative coherence length. For the low coherent case there is a circular phase dislocation. In the coherent limit coherence vortices become intensity vortices of fully coherent Laguerre-Gaussian beams.

  18. Brilliant gamma beams for industrial applications: new opportunities, new challenges

    Science.gov (United States)

    Iancu, V.; Suliman, G.; Turturica, G. V.; Iovea, M.; Daito, I.; Ohgaki, H.; Matei, C.; Ur, C. A.; Balabanski, D. L.

    2016-10-01

    The Nuclear Physics oriented pillar of the pan-European Extreme Light Infrastructure (ELI-NP) will host an ultra-bright, energy tunable, and quasi-monochromatic gamma-ray beam system in the range of 0.2-19.5 MeV produced by laser-Compton backscattering technique. The applied research program envisioned at ELI-NP targets to use nuclear resonance fluorescence (NRF) and computed tomography to provide new opportunities for industry and society. High sensitivity NRF-based investigations can be successfully applied to safeguard applications and management of radioactive wastes as well as to uncharted fields like cultural heritage and medical imaging. Gamma-ray radioscopy and computed tomography performed at ELI-NP has the potential to achieve high resolution in industrial-sized objects provided the detection challenges introduced by the unique characteristics of the gamma beam are overcome. Here we discuss the foreseen industrial applications that will benefit from the high quality and unique characteristics of ELI-NP gamma beam and the challenges they present. We present the experimental setups proposed to be implemented for this goal, discuss their performance based on analytical calculations and numerical Monte-Carlo simulations, and comment about constrains imposed by the limitation of current scintillator detectors. Several gamma-beam monitoring devices based on scintillator detectors will also be discussed.

  19. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  20. Heavy metal analysis in groundwater samples by SR-TXRF

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana; Ficaris, Maria [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo. Dept. de Recursos Hidricos]. E-mail: silvana@fec.unicamp.br; Vives, Ana Elisa S. de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Zucchi, Orgheda L.A.D. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Nascimento Filho, Virgilio Franco do [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. Instrumentacao Nuclear]. E-mail: virgilio@cena.usp.br

    2005-07-01

    In order to obtain information about levels of heavy metals in groundwater, analysis were carried out on samples from monitoring and supplying wells located in Campinas, Sao Paulo State, Southeastern Brazil. The analytical technique used was Synchrotron Radiation Total Reflection X-Ray Fluorescence (SR-TXRF) and all the measurements were performed at Synchrotron Light Source Laboratory, using a white beam and a Si(Li) detector in total reflection condition. The determined elements were Al, Cr, Mn, Fe, Ni, Cu, Zn, Ba and Pb. The results were compared with the maximum allowed values (MPV) established by the Brazilian Health Department. The detection limits obtained varying from 0.10 up to 8 {mu}g.L{sup -1} were in agreement with the values presented by others analytical techniques. (author)

  1. Structure of normally deformed states in {sup 80}Sr

    Energy Technology Data Exchange (ETDEWEB)

    Winchell, D. F. [University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Wood, V. Q. [University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Saladin, J. X. [University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Birriel, I. [University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Baktash, C. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Brinkman, M. J. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Jin, H.-Q. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Rudolph, D. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Yu, C.-H. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Devlin, M. [Washington University, St. Louis, Missouri 63130 (United States)] (and others)

    2000-04-01

    High-spin states were populated in {sup 80}Sr with the reaction {sup 58}Ni({sup 28}Si,{alpha}2p), using a 130 MeV {sup 28}Si beam from the 88-Inch Cyclotron at LBNL. Gamma rays were detected with Gammasphere, and evaporated alphas and protons were detected with the Microball. The level scheme has been extended, and angular distributions of many of the transitions have been measured. A portion of the data was taken using a backed target, allowing lifetime measurements. No evidence for band termination was found in the spin range studied, but a cranking model analysis indicates possible shape evolution at higher spin. (c) 2000 The American Physical Society.

  2. Pixel Detector Trial Assembly Test in the SR1 building

    CERN Document Server

    D. Giugni

    2004-01-01

    During the last two months the Pixel group [LBL, Milan and Wuppertal] made a successful integration test on the mechanics of the barrel. The scope of the test was to qualify the integration procedures and the various assembling tools. The test took place in the clean room of the SR1 building at CERN, where the detector has been assembled around a dummy beam pipe made of Stainless Steel. The process is rather complex: the shells come in two parts and they have to be clamped together to get the full shell. This operation is carried out by a dedicated tool which is shown to the right in the picture below. The layer 1 shell is clamped around a "service" pipe that will be used for moving the full layer to the integration tool [ITT] which is visible on the left. View of the tools devoted to the Pixel barrel integration in the SR1 building Also visible in the picture is the global frame that is actually held by the tool. It will engage the layers sliding onto the rails. The first two layers are sequentially...

  3. A correlated study between effective total macroscopic cross sections and effective energies for neutron beams with continuous spectra

    CERN Document Server

    Kobayashi, H

    1999-01-01

    Two practically useful quantities have been introduced to characterize a continuous-energy-spectrum neutron beam and to describe transmission phenomena of the beam in the field of quantitative neutron radiography. These quantities are the effective energy instead of a peak energy or a mean energy of the spectrum and an effective total macroscopic (ETM) cross section instead of a total macroscopic (TM) cross section as defined for a monochromatic energy. Four neutron beams have been used to measure ETM cross sections at effective energies of 29.8, 17.2, 9.8 meV, and at the In resonance energy of 1.46 eV. Results are studied as a function of estimated effective energy, where the effective energy was estimated by a beam quality indicator (BQI) which has been proposed recently. Validity of ETM cross sections as a function of the effective energy is discussed and correlated with recent nuclear data.

  4. Creating Ruddlesden-Popper phases by hybrid molecular beam epitaxy

    Science.gov (United States)

    Haislmaier, Ryan C.; Stone, Greg; Alem, Nasim; Engel-Herbert, Roman

    2016-07-01

    The synthesis of a 50 unit cell thick n = 4 Srn+1TinO3n+1 (Sr5Ti4O13) Ruddlesden-Popper (RP) phase film is demonstrated by sequentially depositing SrO and TiO2 layers in an alternating fashion using hybrid molecular beam epitaxy (MBE), where Ti was supplied using titanium tetraisopropoxide (TTIP). A detailed calibration procedure is outlined for determining the shuttering times to deposit SrO and TiO2 layers with precise monolayer doses using in-situ reflection high energy electron diffraction (RHEED) as feedback. Using optimized Sr and TTIP shuttering times, a fully automated growth of the n = 4 RP phase was carried out over a period of >4.5 h. Very stable RHEED intensity oscillations were observed over the entire growth period. The structural characterization by X-ray diffraction and high resolution transmission electron microscopy revealed that a constant periodicity of four SrTiO3 perovskite unit cell blocks separating the double SrO rocksalt layer was maintained throughout the entire film thickness with a very little amount of planar faults oriented perpendicular to the growth front direction. These results illustrate that hybrid MBE is capable of layer-by-layer growth with atomic level precision and excellent flux stability.

  5. Acceleration of relativistic electrons due to resonant interaction with oblique monochromatic whistler-mode waves generated in the ionosphere.

    Science.gov (United States)

    Kuzichev, Ilya; Shklyar, David

    2016-04-01

    One of the most challenging problems of the radiation belt studies is the problem of particles energization. Being related to the process of particle precipitation and posing a threat to scientific instruments on satellites, the problem of highly energetic particles in the radiation belts turns out to be very important. A lot of progress has been made in this field, but still some aspects of the energization process remain open. The main mechanism of particle energization in the radiation belts is the resonant interaction with different waves, mainly, in whistler frequency range. The problem of special interest is the resonant wave-particle interaction of the electrons of relativistic energies. Relativistic resonance condition provides some important features such as the so-called relativistic turning acceleration discovered by Omura et al. [1, 2]. This process appears to be a very efficient mechanism of acceleration in the case of interaction with the whistler-mode waves propagating along geomagnetic field lines. But some whistler-mode waves propagate obliquely to the magnetic field lines, and the efficiency of relativistic turning acceleration in this case is to be studied. In this report, we present the Hamiltonian theory of the resonant interaction of relativistic electrons with oblique monochromatic whistler-mode waves. We have shown that the presence of turning point requires a special treatment when one aims to derive the resonant Hamiltonian, and we have obtained two different resonant Hamiltonians: one to be applied far enough from the turning point, while another is valid in the vicinity of the turning point. We have performed numerical simulation of relativistic electron interaction with whistler-mode waves generated in the ionosphere by a monochromatic source. It could be, for example, a low-frequency transmitter. The wave-field distribution along unperturbed particle trajectory is calculated by means of geometrical optics. We show that the obliquity of

  6. Precision measurement of transverse velocity distribution of a strontium atomic beam

    OpenAIRE

    Gao, F.; H. Liu; Xu, P.; X. Tian; Y. Wang; Ren, J; Haibin Wu; Hong Chang

    2014-01-01

    We measure the transverse velocity distribution in a thermal Sr atomic beam precisely by velocity-selective saturated fluorescence spectroscopy. The use of an ultrastable laser system and the narrow intercombination transition line of Sr atoms mean that the resolution of the measured velocity can reach 0.13 m/s, corresponding to 90$\\mu K$ in energy units. The experimental results are in very good agreement with the results of theoretical calculations. Based on the spectroscopic techniques use...

  7. Effect of new and conventional technological processes on the terroir marker 87Sr/86Sr

    Directory of Open Access Journals (Sweden)

    Catarino Sofia

    2016-01-01

    Full Text Available Aiming to use the strontium isotopic ratio 87Sr/86Sr for traceability and authentication of wine, it is crucial to understand the impacts of anthropogenic factor and technological processes on this parameter. In this study the effect of two technologies: nanofiltration (NF, applied for wine dealcoholisation (1, and ageing with oak wood staves (2, on 87Sr/86Sr ratio of wines from Portuguese Designations of Origin (DO, was assessed. Control wines, NF processed wines and wooden aged wines were evaluated for chemical composition, multi-elemental composition and 87Sr/86Sr ratio by Q-ICP-MS. Regarding NF experiments, high rejections to mineral elements, including heavy metals, were observed. Bearing in mind the several roles played by these elements in wine, this knowledge is of strategic importance in order to guarantee that NF process does not adversely affect product quality. Concerning wood ageing experiment, results indicate the influence of this technological process on metal physical-chemical stability. In the experimental conditions of this study, no significant effect of NF process and wood ageing on 87Sr/86Sr ratio was observed, suggesting that the application of these technologies in wine production is not a limitative factor for the use of 87Sr/86Sr ratio as a geographical origin marker.

  8. Maxdose-SR and popdose-SR routine release atmospheric dose models used at SRS

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, G. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Trimor, P. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-28

    MAXDOSE-SR and POPDOSE-SR are used to calculate dose to the offsite Reference Person and to the surrounding Savannah River Site (SRS) population respectively following routine releases of atmospheric radioactivity. These models are currently accessed through the Dose Model Version 2014 graphical user interface (GUI). MAXDOSE-SR and POPDOSE-SR are personal computer (PC) versions of MAXIGASP and POPGASP, which both resided on the SRS IBM Mainframe. These two codes follow U.S. Nuclear Regulatory Commission (USNRC) Regulatory Guides 1.109 and 1.111 (1977a, 1977b). The basis for MAXDOSE-SR and POPDOSE-SR are USNRC developed codes XOQDOQ (Sagendorf et. al 1982) and GASPAR (Eckerman et. al 1980). Both of these codes have previously been verified for use at SRS (Simpkins 1999 and 2000). The revisions incorporated into MAXDOSE-SR and POPDOSE-SR Version 2014 (hereafter referred to as MAXDOSE-SR and POPDOSE-SR unless otherwise noted) were made per Computer Program Modification Tracker (CPMT) number Q-CMT-A-00016 (Appendix D). Version 2014 was verified for use at SRS in Dixon (2014).

  9. Comprehensive Analysis of Photosynthetic Characteristics and Quality Improvement of Purple Cabbage under Different Combinations of Monochromatic Light

    Science.gov (United States)

    Yang, Biyun; Zhou, Xiangzhu; Xu, Ru; Wang, Jin; Lin, Yizhang; Pang, Jie; Wu, Shuang; Zhong, Fenglin

    2016-01-01

    Light is essential for plant growth. Light intensity, photoperiod, and light quality all affect plant morphology and physiology. Compared to light intensity, photoperiod, little is known about the effects of different monochromatic lights on crop species. To investigate how different lighting conditions influence crops with heterogeneous colors in leaves, we examined photosynthetic characteristics and quality (regarding edibility and nutrition) of purple cabbage under different combinations of lights. Eight different treatments were applied including monochromic red (R), monochromic blue (B), monochromic yellow (Y), monochromic green (G), and the combination of red and blue (3/1, RB), red/blue/yellow (3/1/1, RBY), red/blue/green (3/1/1,RBG), and white light as the control. Our results indicate that RBY (3/1/1) treatment promotes the PSII activity of purple cabbage, resulting in improved light energy utilization. By contrast, both G and Y lights alone have inhibitory effect on the PSII activity of purple cabbage. In addition, RBY (3/1/1) significantly boosts the anthocyanin and flavonoids content compared with other treatments. Although we detected highest soluble protein and vitamin C content under B treatment (increased by 30.0 and 14.3% compared with the control, respectively), RBY (3/1/1) appeared to be the second-best lighting condition (with soluble protein and vitamin C content increased by 8.6 and 4.1%, respectively compared with the control). Thus we prove that the addition of yellow light to the traditional combination of red/blue lighting conditions is beneficial to synthesizing photosynthetic pigments and enables superior outcome of purple cabbage growth. Our results indicate that the growth and nutritional quality of purple cabbage are greatly enhanced under RBY (3/1/1) light, and suggest that strategical management of lighting conditions holds promise in maximizing the economic efficiency of plant production and food quality of vegetables grown in

  10. Effect of melatonin on monochromatic light-induced T-lymphocyte proliferation in the thymus of chickens.

    Science.gov (United States)

    Chen, Fuju; Reheman, Aikebaier; Cao, Jing; Wang, Zixu; Dong, Yulan; Zhang, Yuxian; Chen, Yaoxing

    2016-08-01

    A total of 360 post-hatching day 0 (P0) Arbor Acre male broilers, including intact, sham operation and pinealectomy groups, were exposed to white light (WL), red light (RL), green light (GL) and blue light (BL) from a light-emitting diode (LED) system until for P14. We studied the effects of melatonin and its receptors on monochromatic light-induced T-lymphocyte proliferation in the thymus of broilers. The density of proliferating cell nuclear antigen (PCNA) cells and the proliferation of T-lymphocytes in response to Concanavalin A (ConA) in GL significantly increased both in vivo and in vitro (from 9.57% to 32.03% and from 34.30% to 50.53%, respectively) compared with other lights (plights (p<0.005). However, exogenous melatonin (10(-9)M) significantly increased the proliferative activity of T-lymphocyte by 9.64% (p=0.002). In addition, GL significantly increased mRNA expression levels of Mel1a, Mel1b and Mel1c receptors from 21.09% to 32.57%, and protein expression levels from 24.43% to 42.92% compared with RL (p<0.05). However, these effects were blocked after pinealectomy. Furthermore, 4P-PDOT (a selective Mel1b antagonist) and prazosin (a selective Mel1c antagonist) attenuated GL-induced T-lymphocyte proliferation in response to ConA (p=0.000). Luzindole (a nonselective Mel1a/Mel1b antagonist), however, did not induce these effects (p=0.334). These results suggest that melatonin may mediate GL-induced T-lymphocyte proliferation via the Mel1b and Mel1c receptors but not via the Mel1a receptor.

  11. Monochromatic Minibeams Radiotherapy: From Healthy Tissue-Sparing Effect Studies Toward First Experimental Glioma Bearing Rats Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Deman, Pierre [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); European Synchrotron Radiation Facility, Grenoble (France); Vautrin, Mathias [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); European Synchrotron Radiation Facility, Grenoble (France); DOSIsoft, Cachan (France); Edouard, Magali [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); European Synchrotron Radiation Facility, Grenoble (France); Stupar, Vasile [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); Bobyk, Laure; Farion, Regine [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); European Synchrotron Radiation Facility, Grenoble (France); Elleaume, Helene [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); European Synchrotron Radiation Facility, Grenoble (France); Grenoble University Hospital, Grenoble (France); Remy, Chantal; Barbier, Emmanuel L. [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); Esteve, Francois [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); European Synchrotron Radiation Facility, Grenoble (France); Grenoble University Hospital, Grenoble (France); Adam, Jean-Francois, E-mail: adam@esrf.fr [INSERM, Grenoble (France); Universite Joseph Fourier, Institut des Neurosciences, Grenoble (France); European Synchrotron Radiation Facility, Grenoble (France); Grenoble University Hospital, Grenoble (France)

    2012-03-15

    Purpose: The purpose of this study was to evaluate high-dose single fraction delivered with monochromatic X-rays minibeams for the radiotherapy of primary brain tumors in rats. Methods and Materials: Two groups of healthy rats were irradiated with one anteroposterior minibeam incidence (four minibeams, 123 Gy prescribed dose at 1 cm depth in the brain) or two interleaved incidences (54 Gy prescribed dose in a 5 Multiplication-Sign 5 Multiplication-Sign 4.8 mm{sup 3} volume centered in the right hemisphere), respectively. Magnetic resonance imaging (MRI) follow-up was performed over 1 year. T2-weighted (T2w) images, apparent diffusion coefficient (ADC), and blood vessel permeability maps were acquired. F98 tumor bearing rats were also irradiated with interleaved minibeams to achieve a homogeneous dose of 54 Gy delivered to an 8 Multiplication-Sign 8 Multiplication-Sign 7.8 mm{sup 3} volume centered on the tumor. Anatomic and functional MRI follow-up was performed every 10 days after irradiation. T2w images, ADC, and perfusion maps were acquired. Results: All healthy rats were euthanized 1 year after irradiation without any clinical alteration visible by simple examination. T2w and ADC measurements remain stable for the single incidence irradiation group. Localized Gd-DOTA permeability, however, was observed 9 months after irradiation for the interleaved incidences group. The survival time of irradiated glioma bearing rats was significantly longer than that of untreated animals (49 {+-} 12.5 days versus 23.3 {+-} 2 days, p < 0.001). The tumoral cerebral blood flow and blood volume tend to decrease after irradiation. Conclusions: This study demonstrates the sparing effect of minibeams on healthy tissue. The increased life span achieved for irradiated glioma bearing rats was similar to the one obtained with other radiotherapy techniques. This experimental tumor therapy study shows the feasibility of using X-ray minibeams with high doses in brain tumor radiotherapy.

  12. Impact of different monochromatic LED light colours and bird age on the behavioural output and fear response in ducks

    Directory of Open Access Journals (Sweden)

    Shabiha Sultana

    2013-12-01

    Full Text Available This study was performed to observe the effect of monochromatic light emitting diode (LED light colour and bird age on the behaviour and fear response of ducks. A total of 200 1-day-old ducklings were used in the experiment (two replications, 25 ducklings/pen, and lighting was set up as follows: white (W, control, 400-770 nm, yellow (Y, 600 nm, green (G, 520 nm and blue (B, 460 nm LED lights. Ducks were subjected to 23L: 1D h lighting with 0.1 Watt/m2 light intensity. Video was recorded twice per day (2 h in the morning and 2 h in the afternoon and observed five consecutive days per week. Duration of feeding, drinking, sitting, walking, standing, preening, wing flapping, wing stretching, tail wagging, head shaking, body shaking, ground pecking, peck object, and social interaction behaviour were recorded. At 3 and 6 weeks of age, 10 birds per treatment were subjected to the tonic immobility (TI test (three times/duck. Ducks reared in Y and W light were more active, as expressed by more walking, ground pecking, drinking and social interaction activities than those of ducks under the B light treatment (P<0.05. Ducks showed more time sitting, standing, and preening under B light (P<0.05. Feeding, sitting, standing and drinking behaviours increased, and walking and social interaction behaviours decreased with age of the ducks (P<0.05. Differences in behaviours among different light colours were observed. In addition, the TI test results indicated that B and G light reduced the fear response of the ducks.

  13. Examination of SR101 shipping packages

    Energy Technology Data Exchange (ETDEWEB)

    Daugherty, W. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-03-01

    Four SR101 shipping packages were removed from service and provided for disassembly and examination of the internal fiberboard assemblies. These packages were 20 years old, and had experienced varying levels of degradation. Two of the packages were successfully disassembled and fiberboard samples were removed from these packages and tested. Mechanical and thermal property values are generally comparable to or higher than baseline values measured on fiberboard from 9975 packages, which differs primarily in the specified density range. While baseline data for the SR101 material is not available, this comparison with 9975 material suggests that the material properties of the SR101 fiberboard have not significantly degraded.

  14. Beam-beam effects in the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V.; Alexahin, Y.; Lebedev, V.; Lebrun, P.; Moore, R.S.; Sen, T.; Tollestrup, A.; Valishev, A.; Zhang, X.L.; /Fermilab

    2005-01-01

    The Tevatron in Collider Run II (2001-present) is operating with 6 times more bunches, many times higher beam intensities and luminosities than in Run I (1992-1995). Electromagnetic long-range and head-on interactions of high intensity proton and antiproton beams have been significant sources of beam loss and lifetime limitations. We present observations of the beam-beam phenomena in the Tevatron and results of relevant beam studies. We analyze the data and various methods employed in operations, predict the performance for planned luminosity upgrades, and discuss ways to improve it.

  15. Precision measurement of transverse velocity distribution of a Strontium atomic beam

    CERN Document Server

    Gao, F; Xu, P; Tian, X; Wang, Y; Ren, J; Wu, Haibin; Chang, Hong

    2013-01-01

    We measure precisely the transverse velocity distribution in a thermal Sr atomic beam with a velocity selective saturated fluorescence spectroscopy. By using the ultrastable laser system and narrow intercombination transition line of Sr atoms, the resolution of the velocity measured can be reached 0.13m/s, corresponding to 90$\\mu K$ in energy unit. The experimental results are agreement very well with a theoretical calculation. With the spectroscopic techniques, the absolute frequency of the intercombination transition of $^{88}$Sr is measured by an optical-frequency comb generator referenced to the SI second through an H maser, which is given by 434 829 121 318(10)kHz.

  16. Sr fluxes and isotopic compositions of the eleven rivers originating from the Qinghai-Tibet Plateau and their contributions to 87Sr/86Sr evolution of seawater

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To evaluate influence of chemical weathering of the Qinghai-Tibet Plateau (QTP) on seawater 87Sr/86Sr variation, river water and sediment samples were collected, and their Sr concentrations and isotopic compositions analyzed, from the seven large rivers that originated from the QTP. By combining these with the data of the Ganges, Brahmaputra, Indus and Irrawaddy originated in the southern QTP, the total Sr flux of the eleven rivers reaches 3.47×109 mol·a-1, which accounts for 10.2% of the total Sr flux transported by the global rivers. The weighted mean 87Sr/86Sr is 0.71694, higher than the average value of the global rivers. The 87Srex (87Sr flux in excess of the seawater 87Sr/86Sr ratio) of the Chinese seven rivers is 1.55×106 mol·a-1, only accounting for about 6% of the value of the eleven rivers originated from QTP, and the Ganges-Brahmaputra system accounts for 86%. We assume that the QTP rivers have no strontium contributions to the oceans before ~40 Ma and the Sr fluxes of the global rivers, except the QTP eleven rivers, are constant, then a maximum linear increase in Sr fluxes of the QTP rivers from zero to the modern value in response to tectonic uplift can explain ~69% increase of seawater 87Sr/86Sr over the past ~40 Ma and the remainder of 31% is perhaps provided from other factors.

  17. Band gap tuning of epitaxial SrTiO{sub 3-δ}/Si(001) thin films through strain engineering

    Energy Technology Data Exchange (ETDEWEB)

    Cottier, Ryan J.; Steinle, Nathan A.; Currie, Daniel A.; Theodoropoulou, Nikoleta, E-mail: ntheo@txstate.edu [Physics Department, Texas State University, San Marcos, Texas 78666 (United States)

    2015-11-30

    We investigate the effect of strain and oxygen vacancies (V{sub O}) on the crystal and optical properties of oxygen deficient, ultra-thin (4–30 nm) films of SrTiO{sub 3-δ} (STO) grown heteroepitaxially on p-Si(001) substrates by molecular beam epitaxy. We demonstrate that STO band gap tuning can be achieved through strain engineering and show that the energy shift of the direct energy gap transition of SrTiO{sub 3-δ}/Si films has a quantifiable dimensional and doping dependence that correlates well with the changes in crystal structure.

  18. Disturbed Sr and Nd Isotope Systematics in Zircons With Concordant SHRIMP U-Pb Ages

    Science.gov (United States)

    Weaver, K. L.; Bennett, V. C.; Depaolo, D. J.; Mundil, R.

    2004-12-01

    Little is known about the Sr- and Nd-isotopic systematics of zircon. With slow diffusion rates and a high resistance to weathering, zircon should preserve accurate age information and initial Sr and Nd isotopic ratios. As a common accessory mineral, it could provide petrogenetic information for rocks that have been altered, weathered, or metamorphosed. We have investigated the Sm-Nd and Rb-Sr systematics of zircons from unmetamorphosed granitic rocks that have yielded concordant U-Pb SHRIMP (Sensitive High Resolution Ion Microprobe) ages and have depleted mantle signatures for Nd and Sr isotopes. Zircon populations from mantle-derived igneous rocks with ages of 0.1, 1.7, and 3.8 Ga were chosen for Sr and Nd isotopic analysis. Low concentrations (Sr, 4 to 8 ppm and Nd, 6 to 12 ppm) and small grain size necessitate the use of multigrain aliquots. Meaningful results can be obtained only if all of the zircons in the rock are a coherent population with homogeneous ages throughout and among grains. Zircon U-Pb ages were characterized using the SHRIMP RG, and trace element concentrations were measured by LA-ICPMS. The populations are homogeneous and the material ablated by the ion beam ( ˜~20 μ m spot size) shows little evidence of lead loss. Results on zircons of 100 Ma and 1700 Ma indicate that both the Rb-Sr and Sm-Nd systems have been severely disturbed. For the 1700 Ma granitic rocks from the Yavapai sequence of Arizona, zircon Sm-Nd apparent ages are ca. 1000 Ma! Leaching was used to remove contributions from adhering or included minerals, but leached residues that presumably most closely approximate the composition of the pure zircon (e.g. have high Sm/Nd) are no less disturbed than unleached samples. Despite the U-Pb SHRIMP ages indicating a closed system, the zircons have failed to preserve a reasonable age or initial isotopic composition for Sr and Nd, indicating that parts of the crystal might be severely affected by radiation damage resulting in disturbed

  19. Separation Sr and Ba From Fission Products Using Sr-spec Resin Column

    Institute of Scientific and Technical Information of China (English)

    WANG; Xiu-feng

    2013-01-01

    Sr and Ba are the IIA group elements,with the same outer electronic structure,and the very similar properties,so separation of the two elements becomes very difficult.The traditional separation method of Sr and Ba in fission products is repeated precipitation of BaCl2·H2O in hydrochloric acid-ether medium.Four times repeated precipitation steps are needed to ensure the decontamination factor of Sr to be better

  20. Joseph C. Risser Sr., 1892–1982

    OpenAIRE

    Manring, M. M.; Calhoun, Jason

    2009-01-01

    This biographical sketch of Joseph C. Risser Sr. corresponds to the historic text, The Classic: The Iliac Apophysis: An Invaluable Sign in the Management of Scoliosis, available at DOI 10.1007/s11999-009-1096-z.

  1. Beam imaging sensor

    Energy Technology Data Exchange (ETDEWEB)

    McAninch, Michael D.; Root, Jeffrey J.

    2016-07-05

    The present invention relates generally to the field of sensors for beam imaging and, in particular, to a new and useful beam imaging sensor for use in determining, for example, the power density distribution of a beam including, but not limited to, an electron beam or an ion beam. In one embodiment, the beam imaging sensor of the present invention comprises, among other items, a circumferential slit that is either circular, elliptical or polygonal in nature.

  2. Radiogenic and stable Sr isotope ratios (87Sr/86Sr, δ88/86Sr) as tracers of riverine cation sources and biogeochemical cycling in the Milford Sound region of Fiordland, New Zealand

    Science.gov (United States)

    Andrews, M. Grace; Jacobson, Andrew D.; Lehn, Gregory O.; Horton, Travis W.; Craw, Dave

    2016-01-01

    This study reports radiogenic Sr isotope ratios (87Sr/86Sr), stable Sr isotope ratios (δ88/86Sr), and major ion concentrations for river, rock, sediment, soil, and plant samples collected from the Cleddau and Hollyford catchments in the Milford Sound region of Fiordland, New Zealand. The catchments primarily drain gabbro, but some tributaries access limestone and volcanogenic sediments. The goal of the study was to understand controls on riverine δ88/86Sr values in a landscape with multiple factors that may influence chemical weathering, including dense vegetation, high rainfall, and abundant, freshly-eroded Holocene fluvio-glacial and landslide debris. Rivers draining gabbro have higher δ88/86Sr values than bedrock, by as much as ∼0.14‰, and the δ88/86Sr values strongly correlate with molar Ca/Sr ratios (R2 = 0.69). Leaching of rocks and sediment reveals no evidence for the preferential dissolution of minerals having high δ88/86Sr values and Ca/Sr ratios. In-stream Sr isotope fractionation seems unlikely because comparison against 87Sr/86Sr and Ca/Sr ratios demonstrates that riverine δ88/86Sr values conservatively trace water-mass mixing. The riverine data are best explained by the input of soil water, which is distinct from potential bedrock end-members (i.e., silicates and carbonates) based on δ88/86Sr but indistinguishable in terms of Ca/Sr and 87Sr/86Sr. While strontium isotope fractionation during secondary mineral formation and pedogenesis is possible, clay mineral formation is minor and most soils are poorly developed. Instead, soil water δ88/86Sr values more likely reflect plant uptake. Plant samples yielded a wide range of δ88/86Sr values, but on average, they are lower than those for bedrock, consistent with the expectation that plants preferentially incorporate lighter Sr isotopes. Mass-balance constraints, together with 87Sr/86Sr ratios, indicate that soil water δ88/86Sr values are ∼0.30‰ higher than bedrock δ88/86Sr values, and

  3. Ultracold ordered electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Habs, D.; Kramp, J.; Krause, P.; Matl, K.; Neumann, R.; Schwalm, D.

    1988-01-01

    We have started an experimental program to develop an ultracold electron beam, which can be used together with a standard electron cooling device in the Heidelberg Test Storage Ring TSR. In contrast to the standard-type design using electron beam extraction beam extraction from a heated cathode, the ultracold beam is produced by photoemission of electrons from a cooled semiconductor crystal irradiated with an intense near-infrared laser light beam. Adiabatic acceleration is expected to provide ordering of the electron beam itself. Besides the cooling of ion beams to extremely low temperatures, with the aim of obtaining crystallization, the ultracold beam will constitute an excellent target for atomic physics experiments.

  4. On the way to high dynamic range beam profile measurements

    Energy Technology Data Exchange (ETDEWEB)

    Egberts, Jan; Artikova, Sayyora [Max-Planck-Institut fuer Kernphysik (Germany); Welsch, Carsten [University of Liverpool (United Kingdom); Cockcroft Institute of Accelerator Science and Technology (United Kingdom)

    2009-07-01

    A thorough understanding of halo formation and its possible control is highly desirable for essentially all particle accelerators. Particles outside the beam core are not only lost for further experiments, they are also likely to hit the drift chamber and thereby activate the beam pipe, which makes work on the accelerator costly and time consuming. A well-established technique for transverse beam profile measurements is synchrotron radiation (SR) for high energy and high luminosity accelerators like the LHC or CTF3. At much lower beam energies, an alternative for transverse beam profile measurements based on the direct measurement of light is optical transition radiation (OTR) or the insertion of a luminescent screen. What applies for essentially all these light generation processes, is that the light intensity is over a wide range proportional to the particle density, which makes the optical analysis of such light an ideal tool for beam profile measurements. A particular challenge, however, is to distinguish the particles in the tail regions of the beam distribution from the much more intense beam core. In this contribution, we present results from laboratory measurements on two different devices that might form the technical base of a future beam halo monitor: the novel SpectraCam XDR camera system and a flexible masking technique based on a DMD micro mirror array.

  5. Empirical beam hardening correction (EBHC) for CT

    Energy Technology Data Exchange (ETDEWEB)

    Kyriakou, Yiannis; Meyer, Esther; Prell, Daniel; Kachelriess, Marc [Institute of Medical Physics, University of Erlangen-Nuernberg, 91052 Erlangen (Germany)

    2010-10-15

    Purpose: Due to x-ray beam polychromaticity and scattered radiation, attenuation measurements tend to be underestimated. Cupping and beam hardening artifacts become apparent in the reconstructed CT images. If only one material such as water, for example, is present, these artifacts can be reduced by precorrecting the rawdata. Higher order beam hardening artifacts, as they result when a mixture of materials such as water and bone, or water and bone and iodine is present, require an iterative beam hardening correction where the image is segmented into different materials and those are forward projected to obtain new rawdata. Typically, the forward projection must correctly model the beam polychromaticity and account for all physical effects, including the energy dependence of the assumed materials in the patient, the detector response, and others. We propose a new algorithm that does not require any knowledge about spectra or attenuation coefficients and that does not need to be calibrated. The proposed method corrects beam hardening in single energy CT data. Methods: The only a priori knowledge entering EBHC is the segmentation of the object into different materials. Materials other than water are segmented from the original image, e.g., by using simple thresholding. Then, a (monochromatic) forward projection of these other materials is performed. The measured rawdata and the forward projected material-specific rawdata are monomially combined (e.g., multiplied or squared) and reconstructed to yield a set of correction volumes. These are then linearly combined and added to the original volume. The combination weights are determined to maximize the flatness of the new and corrected volume. EBHC is evaluated using data acquired with a modern cone-beam dual-source spiral CT scanner (Somatom Definition Flash, Siemens Healthcare, Forchheim, Germany), with a modern dual-source micro-CT scanner (TomoScope Synergy Twin, CT Imaging GmbH, Erlangen, Germany), and with a modern

  6. Photon-exposure-dependent photon-stimulated desorption for obtaining photolysis cross section of molecules adsorbed on surface by monochromatic soft x-ray photons.

    Science.gov (United States)

    Chou, L-C; Jang, C-Y; Wu, Y-H; Tsai, W-C; Wang, S-K; Chen, J; Chang, S-C; Liu, C-C; Shai, Y; Wen, C-R

    2008-12-07

    Photon-exposure-dependent positive- and negative-ion photon-stimulated desorption (PSD) was proposed to study the photoreactions and obtain the photolysis cross sections of molecules adsorbed on a single-crystal surface by monochromatic soft x-ray photons with energy near the core level of adsorbate. The changes in the F(+) and F(-) PSD ion yields were measured from CF(3)Cl molecules adsorbed on Si(111)-7x7 at 30 K (CF(3)Cl dose=0.3x10(15) molecules/cm(2), approximately 0.75 monolayer) during irradiation of monochromatic soft x-ray photons near the F(1s) edge. The PSD ion yield data show the following characteristics: (a) The dissociation of adsorbed CF(3)Cl molecules is due to a combination of direct photodissociation via excitation of F(1s) core level and substrate-mediated dissociation [dissociative attachment and dipolar dissociation induced by the photoelectrons emitting from the silicon substrate]. (b) the F(+) ion desorption is associated with the bond breaking of the surface CF(3)Cl, CF(2)Cl, CFCl, and SiF species. (c) the F(-) yield is mainly due to DA and DD of the adsorbed CF(3)Cl molecules. (d) The surface SiF is formed by reaction of the surface Si atom with the neutral fluorine atom, F(+), or F(-) ion produced by scission of C-F bond of CF(3)Cl, CF(2)Cl, or CFCl species. A kinetic model was proposed for the explanation of the photolysis of this submonolayer CF(3)Cl-covered surface. Based on this model and the variation rates of the F(+)F(-) signals during fixed-energy monochromatic photon bombardment at 690.2 and 692.6 eV [near the F(1s) edge], the photolysis cross section was deduced as a function of energy.

  7. Effects of monochromatic light stimuli on the development and Muc2 expression of goblet cells in broiler small intestines during embryogenesis.

    Science.gov (United States)

    Yu, Y; Wang, Z; Cao, J; Dong, Y; Wang, T; Chen, Y

    2014-07-01

    The effects of monochromatic light on the ontogeny, differentiation, and Muc2 expression level in goblet cells were studied in the small intestines of late-stage broiler embryos. The embryos were exposed to blue light (B group), green light (G group), red light (R group), or darkness (D group) throughout the incubation period. On d 15 of incubation (E15), a few acidic goblet cells (only the sulfated subtype) were observed, and Muc2 mRNA expression was detected. On E18, however, neutral, acidic, and intermediate types, as well as the sulfated subtype, were observed in the small intestine, and a decreasing gradient of goblet cell density was found along the duodenum to ileum axis. Up to E21, 3 types of goblet cells and 3 acidic cell subtypes were found in all the small intestines. The goblet cell density increased along the duodenum to ileum axis. Monochromatic light stimulation resulted in no significant differences in the density and types of goblet cells between the different treatment groups on E15 and E18, but an increased Muc2 mRNA expression level was detected on E18 in the G group compared with the other treatment groups. On E21, the goblet cell density, proportion of acidic goblet cells, and Muc2 mRNA expression level increased in the G group compared with other treatment groups. These results suggest that the ontogeny and differentiation of goblet cells in broiler embryos display temporal and spatial differences. Green monochromatic light may have the potential to promote the proliferation and maturation of as well as the expression of Muc2 mRNA in goblet cells of broiler embryos.

  8. Changes of plasma growth hormone, insulin-like growth factors-I, thyroid hormones, and testosterone concentrations in embryos and broiler chickens incubated under monochromatic green light

    Directory of Open Access Journals (Sweden)

    Lin Zhang

    2014-07-01

    Full Text Available Previous studies showed that monochromatic green light stimuli during embryogenesis accelerated posthatch body weight and pectoral muscle growth of broilers. In this experiment, we further investigated whether the regulation of broiler embryonic or posthatch growth by green light stimulus during incubation is associated with the changes of some important hormones at different ages of embryos and broiler chickens. Fertile broiler eggs (Arbor Acres, n=880 were pre-weighed and randomly assigned 1 of 2 incubation treatment groups: i dark condition (control group, and ii monochromatic green light group (560 nm. The monochromatic lighting systems sourced from light-emitting diode lamps were equalised at the intensity of 15 lux (lx at eggshell level. The dark condition was set as a commercial control from day one until hatching. After hatch, 120 day-old male chicks from each group were housed under white light with an intensity of 30 lx at bird-head level. Compared with the dark condition, chicks incubated under the green light showed significantly higher growth hormone (GH levels from 19 d of embryogenesis (E19 to 5 d of posthatch (H5, and higher plasma insulinlike growth factor (IGF-I levels from both E17 to E19 and H3 to H35. No significant differences were found in plasma thyroxine, triiodothyronine, and testosterone in embryos or hatched birds between the 2 groups. These results indicate that somatotropic axis hormones (GH and IGF-I may be the most important contributor to chicken growth promoted by green light stimuli during embryogenesis.

  9. Resonance effects of transition radiation emitted from thin foil stacks using electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Awata, Takaaki; Yajima, Kazuaki; Tanaka, Takashi [Kyoto Univ. (Japan). Faculty of Engineering] [and others

    1997-03-01

    Transition Radiation(TR) X rays are expected to be a high brilliant X-ray source because the interference among TR X rays emitted from many thin foils placed periodically in vacuum can increase their intensity and make them quasi-monochromatic. In order to study the interference (resonance) effects of TR, we measured the energy spectra of TR for several sets of thin-foil stacks at various emission angles. It was found that the resonance effects of TR are classified into intrafoil and interfoil resonances and the intensity of TR X rays increases nonlinearly with increasing foil number, attributing to the interfoil resonance. It became evident that the brilliance of TR is as high as that of SR. (author)

  10. Precision frequency measurement of 1S0-3P1 intercombination lines of Sr isotopes

    Science.gov (United States)

    Liu, Hui; Gao, Feng; Ye-Bing, Wang; Xiao, Tian; Jie, Ren; Ben-Quan, Lu; Qin-Fang, Xu; Yu-Lin, Xie; Hong, Chang

    2015-01-01

    We report on frequency measurement of the intercombination (5s2)1S0-(5s5p)3P1 transition of the four natural isotopes of strontium, including 88Sr (82.58%), 87Sr (7.0%), 86Sr (9.86%), and 84Sr (0.56%). A narrow-linewidth laser that is locked to an ultra-low expansion (ULE) optical cavity with a finesse of 12000 is evaluated at a linewidth of 200 Hz with a fractional frequency drift of 2.8×10-13 at an integration time of 1 s. The fluorescence collector and detector are specially designed, based on a thermal atomic beam. Using a double-pass acousto-optic modulator (AOM) combined with a fiber and laser power stabilization configuration to detune the laser frequency enables high signal-to-noise ratios and precision saturated spectra to be obtained for the six transition lines, which allows us to determine the transition frequency precisely. The optical frequency is measured using an optical frequency synthesizer referenced to an H maser. Both the statistical values and the final values, including the corrections and uncertainties, are derived for a comparison with the values given in other works. Project supported by the National Natural Science Foundation of China (Grant No. 61127901) and the Key Project of the Chinese Academy of Sciences (Grant No. KJZD-EW-W02).

  11. Measurements of Sr/Ca in bones to evaluate differences in temperature

    Energy Technology Data Exchange (ETDEWEB)

    Santos, P.R. [IFUSP, Travessa R da rua do Matao 187, Cidade Universitaria, CEP 05508-970, Sao Paulo, SP (Brazil); Added, N. [IFUSP, Travessa R da rua do Matao 187, Cidade Universitaria, CEP 05508-970, Sao Paulo, SP (Brazil)], E-mail: nemitala@dfn.if.usp.br; Aburaya, J.H.; Rizzutto, M.A. [IFUSP, Travessa R da rua do Matao 187, Cidade Universitaria, CEP 05508-970, Sao Paulo, SP (Brazil)

    2008-04-15

    Analysis of aragonite from sea shells and coral skeletons showed a clear correlation between the strontium and calcium concentrations for these crystals (Sr/Ca ratio) and seawater temperature obtained by satellites and ship readings. In this work we present the results of a study that correlates Sr/Ca ratio with formation temperature of another calcium crystal, the hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}), main mineral compound of teeth and bones from vertebrates. These animals, independent of its thermoregulation pattern (endothermic or ectothermic) have variations of internal temperature along the body. One interesting application of this work is to differentiate warm-blooded animals from cold-blooded ones just by measuring Sr/Ca ratio in their bones. Bones from a crocodile from Caiman yacare species and two dogs, a poodle and a non defined race, were analyzed using PIXE technique and thick target correction. A 1.78 (18) MeV external proton beam was used in LAMFI-USP with an accumulated charge of about 10 {mu}C for probing the samples. Emitted X-rays were collected using Si-PIN detectors (140 keV for Fe). As in coral skeletons, the Sr/Ca ratio of animals is lower in the body's warmer parts and higher in colder parts.

  12. Beam Stop for Electron Accelerator Beam Characterisation

    Science.gov (United States)

    Roach, Greg; Sharp, Vic; Tickner, James; Uher, Josef

    2009-08-01

    Electron linear accelerator applications involving the generation of hard X-rays frequently require accurate knowledge of the electron beam parameters. We developed a beam stop device which houses a tungsten Bremsstrahlung target and enables the electron beam current, energy and position to be monitored. The beam stop consisted of four plates. The first was a removable aluminium (Al) transmission plate. Then followed the tungsten target. Behind the target there were four Al quadrant plates for beam position measurement. The last plate was a thick Al back-stop block. Currents from the four quadrants and the back-stop were measured and the beam lateral position, energy and current were calculated. The beam stop device was optimised using Monte-Carlo simulation, manufactured (including custom-made electronics and software) in our laboratory and tested at the ARPANSA (Australian Radiation Protection and Nuclear Safety Agency) linear accelerator in Melbourne. The electron beam energy was determined with a precision of 60 keV at beam energies between 11 and 21 MeV and the lateral beam position was controlled with a precision of 200 mum. The relative changes of the beam current were monitored as well.

  13. Initial application of dual energy CT in enterography: monochromatic images of normal intestinal wall%正常回肠壁双能CT成像

    Institute of Scientific and Technical Information of China (English)

    容蓉; 邱建星; 王霄英; 孙晓伟; 蒋学祥

    2012-01-01

    Objective:To evaluate the image quality of CT enterography (CTE) with monochromatic images of dual energy CT. Methods:Eighteen patients underwent CT enterography with dual energy CT (Gemstone spectral imaging,GSI) examinations. The spectrum analysis was used to select the monochromatic images for obtaining the best contrast-to-noise ratio (CNR) for ileum wall. The CNR and image noise of ileum wall at the selected monochromatic level and the conventional polychromatic images were measured. Two readers assessed the image quality, noise and sharpness of both optimal CNR monochromatic level and the conventional polychromatic images. Results: At the selected monochromatic level,the image noise of monochromatic images was higher than that of polychromatic images (fat: 16. 87±2. 73 vs 14. 58±2. 26,t= 3. 85,P<0. 01;fluid: 16. 08±4. 17 vs 13. 51 ±2. 85,t= 4. 96,P<0. 01). The CNR of ileum wall in monochromatic images was also higher than that of polychromatic images (4. 36±0. 71 vs 3. 34±0. 78,t=4. 702,P<0. 01). The intraclass correlation coefficient values among readers for optimal CNR monochromatic images quality was 1. 00. Conclusion: Monochromatic images at optimal CNR keV for CTE can improve CNR for normal ileum wall and improve the overall image quality of CTE.%目的:探讨双能CT小肠成像单能量图像显示正常回肠壁的成像质量及其与混合能量图像在小肠CT成像中的差异.方法:对18例拟诊为炎症性肠病患者行小肠CT成像(CTE),采用双能CT宝石能谱成像技术行CT平扫及双期增强扫描(实质期和延迟期),将实质期图像数据分别进行混合能量和GSI单能量重建,应用能谱分析软件,获得正常回肠壁最佳对比噪声比(CNR)单能图像的KeY值.计算混合能量和单能图像上正常回肠壁的对比噪声比,测量两种图像的噪声并进行配对t检验;由两位医师对两种图像上主动脉锐利度、噪声和图像质量进行主观评分并进行配对t检验,计算组

  14. Monochromatic photography of the Cygnus Loop supernova remnant. Plotting of isophotes of partial nebula radiation in the (OIII) and (NII)+H. cap alpha. lines

    Energy Technology Data Exchange (ETDEWEB)

    Sitnik, T.G.; Toropova, M.S. (Moskovskij Gosudarstvennyj Univ. (USSR). Gosudarstvennyj Astronomicheskij Inst. ' ' GAISh' ' )

    1982-11-01

    System of the isophotes of the 9' size in the west part of the Cyg Loop supernova remnant using monochromatic photographs in the (O3) and (N2)+Hsub(..cap alpha..) lines is obtained. A relative displacement of the regions of emission in these lines is discovered and explained by temperature reduction due to radiative losses behind the shock wave of the supernova explosion. The morphology difference between the (O3) and (N2)+Hsub(..cap alpha..) lines is explained. Anomalously large intensity ratios Isub((O3))/Isub(Hsub(..beta..)) are supposed to be due to spatial separation of the corresponding emission regions.

  15. Photoelectric Characteristic of La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 p-n Heterojunctions

    Institute of Scientific and Technical Information of China (English)

    HUANG Yan-Hong; JIN Kui-Juan; ZHAO Kun; L(U) Hui-Bin; HE Meng; CHEN Zheng-Hao; ZHOU Yue-Liang; YANG Guo-Zhen; MA Xiu-Liang

    2006-01-01

    @@ Good rectifying current-voltage characteristics and nanosecond photoelectric effects are observed in the p-n heterojunctions of La0.gSr0.1MnO3/SrNb0.01 Ti0.99O3 fabricated by laser molecular beam epitaxy. The rise time is about 26ns and the full width at half maximum is about 125ns for the open-circuit photovoltaic pulses when the La0.gSr0.1MnOs film in the heterojunction is irradiated by a laser operated at wavelength 308nm with pulse duration of about 25 ns. A qualitative explanation is presented, based on an analysis of the photoelectric effect of p-n hetero junction.

  16. Electron beam control for barely separated beams

    Science.gov (United States)

    Douglas, David R.; Ament, Lucas J. P.

    2017-04-18

    A method for achieving independent control of multiple beams in close proximity to one another, such as in a multi-pass accelerator where coaxial beams are at different energies, but moving on a common axis, and need to be split into spatially separated beams for efficient recirculation transport. The method for independent control includes placing a magnet arrangement in the path of the barely separated beams with the magnet arrangement including at least two multipole magnets spaced closely together and having a multipole distribution including at least one odd multipole and one even multipole. The magnetic fields are then tuned to cancel out for a first of the barely separated beams to allow independent control of the second beam with common magnets. The magnetic fields may be tuned to cancel out either the dipole component or tuned to cancel out the quadrupole component in order to independently control the separate beams.

  17. Beam Techniques - Beam Control and Manipulation

    Energy Technology Data Exchange (ETDEWEB)

    Minty, Michiko G

    2003-04-24

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization.

  18. Literature in Focus Beta Beams: Neutrino Beams

    CERN Multimedia

    2009-01-01

    By Mats Lindroos (CERN) and Mauro Mezzetto (INFN Padova, Italy) Imperial Press, 2009 The beta-beam concept for the generation of electron neutrino beams was first proposed by Piero Zucchelli in 2002. The idea created quite a stir, challenging the idea that intense neutrino beams only could be produced from the decay of pions or muons in classical neutrino beams facilities or in future neutrino factories. The concept initially struggled to make an impact but the hard work by many machine physicists, phenomenologists and theoreticians over the last five years has won the beta-beam a well-earned position as one of the frontrunners for a possible future world laboratory for high intensity neutrino oscillation physics. This is the first complete monograph on the beta-beam concept. The book describes both technical aspects and experimental aspects of the beta-beam, providing students and scientists with an insight into the possibilities o...

  19. Estimating the distribution of strontium isotope ratios (87Sr/86Sr in the Precambrian of Finland

    Directory of Open Access Journals (Sweden)

    Lars Kaislaniemi

    2011-12-01

    Full Text Available A method to estimate the 87Sr/86Sr ratio of a rock based on its age and Rb/Sr ratio is presented. This method, together with data from the Rock Geochemical Database of Finland (n=6544 is used to estimate the 87Sr/86Sr ratios in the Precambrian of Finland and in its different major units. A generalization to cover the whole area of Finland is achieved by smoothing of estimation points. The estimation method is evaluated by comparing its results to published Rb-Sr isotope analyses (n=138 obtained on the Finnish Precambrian. The results show correspondence to different geological units of Finland,but no systematic difference between Archaean and younger areas is evident. Evaluation of the method shows that most of the estimates are reliable and accurate to be used as background material for provenance studies in archaeology, paleontology and sedimentology. However, some granitic rocks may have large (>1.0 % relative errors.Strontium concentration weighted average of the estimates differs only by 0.001 from the average 87Sr/86Sr ratio (0.730 of the rivers on the Fennoscandian shield.

  20. Maskless, resistless ion beam lithography

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Qing [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithography is the only one that can provide both maskless and resistless patterning. As such, it can potentially make nano-fabrication much simpler. This thesis investigates a focused ion beam system for maskless, resistless patterning that can be made practical for high-volume production. In order to achieve maskless, resistless patterning, the ion source must be able to produce a variety of ion species. The compact FIB system being developed uses a multicusp plasma ion source, which can generate ion beams of various elements, such as O2+, BF2+, P+ etc., for surface modification and doping applications. With optimized source condition, around 85% of BF2+, over 90% of O2+ and P+ have been achieved. The brightness of the multicusp-plasma ion source is a key issue for its application to maskless ion beam lithography. It can be substantially improved by optimizing the source configuration and extractor geometry. Measured brightness of 2 keV He+ beam is as high as 440 A/cm2Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O2+ ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O2+ ions with the dose of 1015 cm-2. The oxide can then serve as a hard mask for patterning of the Si film. The

  1. Maskless, resistless ion beam lithography

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Qing

    2003-03-10

    As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithography is the only one that can provide both maskless and resistless patterning. As such, it can potentially make nano-fabrication much simpler. This thesis investigates a focused ion beam system for maskless, resistless patterning that can be made practical for high-volume production. In order to achieve maskless, resistless patterning, the ion source must be able to produce a variety of ion species. The compact FIB system being developed uses a multicusp plasma ion source, which can generate ion beams of various elements, such as O{sub 2}{sup +}, BF{sub 2}{sup +}, P{sup +} etc., for surface modification and doping applications. With optimized source condition, around 85% of BF{sub 2}{sup +}, over 90% of O{sub 2}{sup +} and P{sup +} have been achieved. The brightness of the multicusp-plasma ion source is a key issue for its application to maskless ion beam lithography. It can be substantially improved by optimizing the source configuration and extractor geometry. Measured brightness of 2 keV He{sup +} beam is as high as 440 A/cm{sup 2} {center_dot} Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O{sub 2}{sup +} ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O{sub 2}{sup +} ions with the dose of 10{sup 15} cm{sup -2}. The oxide can then serve as a hard mask for patterning of the Si film. The process flow and the experimental results for directly patterned poly-Si features

  2. Telecommunication using muon beams

    Science.gov (United States)

    Arnold, Richard C.

    1976-01-01

    Telecommunication is effected by generating a beam of mu mesons or muons, varying a property of the beam at a modulating rate to generate a modulated beam of muons, and detecting the information in the modulated beam at a remote location.

  3. ISR beam scrapers

    CERN Multimedia

    1972-01-01

    Beam scrapers seen in the direction of the beam. The two horizontal scraper foils are near the centre of the beam pipe andthe two scrapers for protection of the vacuum chamber are further outside. In the lower part of the beam pipe is the vertical halo scraping blade.

  4. Ultracold Ordered Electron Beam

    Science.gov (United States)

    Habs, D.; Kramp, J.; Krause, P.; Matl, K.; Neumann, R.; Schwalm, D.

    1988-01-01

    We have started an experimental program to develop an ultracold electron beam, which can be used together with a standard electron cooling device in the Heidelberg Test Storage Ring TSR. In contrast to the standard-type design using electron beam extraction from a heated cathode, the ultracold beam is produced by photoemission of electrons from a cooled semiconductor crystal irradiated with an intense near-infrared laser light beam. Adiabatic acceleration is expected to provide ordering of the electron beam itself. Besides the cooling of ion beams to extremely low temperatures, with the aim of obtaining crystallization, the ultracold beam will constitute an excellent target for atomic physics experiments.

  5. Photosynthetic biomineralization of radioactive Sr via microalgal CO2 absorption.

    Science.gov (United States)

    Lee, Seung Yeop; Jung, Kwang-Hwan; Lee, Ju Eun; Lee, Keon Ah; Lee, Sang-Hyo; Lee, Ji Young; Lee, Jae Kwang; Jeong, Jong Tae; Lee, Seung-Yop

    2014-11-01

    Water-soluble radiostrontium ((90)Sr) was efficiently removed as a carbonate form through microalgal photosynthetic process. The immobilization of soluble (90)Sr radionuclide and production of highly-precipitable radio-strontianite ((90)SrCO3) biomineral are achieved by using Chlorella vulgaris, and the biologically induced mineralization drastically decreased the (90)Sr radioactivity in water to make the highest (90)Sr removal ever reported. The high-resolution microscopy revealed that the short-term removal of soluble (90)Sr by C. vulgaris was attributable to the rapid and selective carbonation of (90)Sr together with the consumption of dissolved CO2 during photosynthesis. A small amount of carbonate in water could act as Sr(2+) sinks through the particular ability of the microalga to make the carbonate mineral of Sr stabilized firmly at the surface site.

  6. A compact micro-beam system using a tapered glass capillary for proton-induced X-ray radiography

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Jun [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)], E-mail: jhasegaw@nr.titech.ac.jp; Shiba, Shigeki; Fukuda, Hitoshi; Oguri, Yoshiyuki [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

    2008-05-15

    A compact micro-beam system, containing a tapered glass capillary tube with a tip diameter on the order of 10 {mu}m, was constructed to examine the applicability of capillary-generated micro-beams to high-contrast radiography based on proton-induced quasi-monochromatic X-rays. The transport efficiency of swift protons (2-3 MeV) through the capillary was examined as a function of the capillary tilt angle and the capillary tip diameter. We obtained transport efficiencies of approximately three times larger than would be expected from the geometrical shape of the capillary. This enhancement indicates that a focusing effect occurred in the capillary. A metallic thin foil was irradiated with the micro-beam and quasi-monochromatic X-rays were produced. By calculating the X-ray yields induced by proton bombardment in the foil and comparing them with the X-ray counts observed at the detector, the throughput efficiency of the X-ray imaging system was evaluated. We demonstrated magnification radiography of a small object to show that a spatial resolution on the order of 10 {mu}m was achievable in our system.

  7. Electronic and Magnetic Properties of Epitaxial Perovskite SrCrO3(001)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, K. H. L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Univ. of Cambridge (United Kingdom); Du, Y. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sushko, P. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bowden, M. E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shutthanandan, V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qiao, L. [Univ. of Manchester (United Kingdom); Cao, G. X. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gai, Z. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sallis, S. [Binghamton Univ., NY (United States); Piper, L. F. J. [Binghamton Univ., NY (United States); Chambers, S. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-06-03

    We investigated the intrinsic properties of SrCrO3 epitaxial thin films synthesized by molecular beam epitaxy. We found compelling evidence that SrCrO3 is a correlated metal. X-ray photoemission valence band and O K-edge x-ray absorption spectra indicate a strongly hybridized Cr3d–O2p state crossing the Fermi level, leading to metallic behavior. Furthermore, a comparison between valence band spectra near the Fermi level and the densities of states calculated using density functional theory (DFT) suggests the presence of coherent and incoherent states and points to strong electron correlation effects. The magnetic susceptibility can be described by Pauli paramagnetism at temperatures above 100 K, but reveals antiferromagnetic behavior at lower temperatures, possibly resulting from orbital ordering.

  8. Electronic and magnetic properties of epitaxial perovskite SrCrO3(001)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongliang; Du, Yingge; Sushko, Petr; Bowden, Mark E.; Shutthanandan, V.; Qiao, Liang; Cao, Guixin; Gai, Zheng; Sallis, Shawn; Piper, L.F.J.; Chambers, Scott A.

    2015-06-24

    We have investigated the intrinsic properties of SrCrO3 epitaxial thin films synthesized by molecular beam epitaxy. We find compelling evidence that SrCrO3 is a correlated metal. X-ray photoemission valence band and O K-edge x-ray absorption spectra indicate a strongly hybridized Cr3d-O2p state crossing the Fermi level, leading to metallic behavior. Comparison between valence band spectra near the Fermi level and the densities of states calculated using density functional theory (DFT) also suggests the presence of coherent and incoherent states and points to a strong electron-electron correlation effects. The magnetic susceptibility can be described by Pauli paramagnetism at temperatures above 100 K, but reveals antiferromagnetic behavior at lower temperatures resulting from orbital ordering as suggested by Ortega-San-Martin et al. [Phys. Rev. Lett. 99, 255701 (2007)].

  9. Species arboreal as a bioindicator of the environmental pollution: Analysis by SR-TXRF

    Energy Technology Data Exchange (ETDEWEB)

    Sirito de Vives, Ana Elisa [Methodist University of Piracicaba, Rodovia Iracemapolis/Santa Barbara, km 01, Santa Barbara D' Oeste 13450-000, SP (Brazil)], E-mail: aesvives@unimep.br; Moreira, Silvana [State University of Campinas, Cidade Universitaria ' Zeferino Vaz' , Campinas 13083-970, SP (Brazil); Boscolo Brienza, Sandra Maria [Methodist University of Piracicaba, Rodovia do Acucar, Km 156, Piracicaba 13400-911, SP (Brazil); Medeiros, Jean Gabriel S.; Filho, Mario Tomazello [University of Sao Paulo, Av. Padua Dias, 11 Piracicaba 13418-900, SP (Brazil); Araujo Domingues Zucchi, Orgheda Luiza [University of Sao Paulo, Av. dos Bandeirantes, 390 Ribeirao Preto 14040-901, SP (Brazil); Nascimento Filho, Virgilio Franco do [University of Sao Paulo, Av. Centenario, 303 Piracicaba 13400-970, SP (Brazil); Barroso, Regina Cely [State University of Rio de Janeiro, Rua Sao Francisco Xavier, 524 Rio de Janeiro 20550-900, RJ (Brazil)

    2007-08-21

    This paper aims to study the environmental pollution in the tree development, in order to evaluate its use as bioindicator in urban and countrysides. The sample collection was carried out in Piracicaba city, Sao Paulo State, that presents high level of environmental contamination in water, soil and air, due to industrial activities, vehicle combustion, sugar-cane leaves burning in the harvesting, etc. The species Caesalpinia peltophoroides ('Sibipiruna') was selected because it is often used in urban arborization. Synchrotron radiation X-ray fluorescence technique (SR-TXRF) was employed to identify and quantify the elements and metals of nutritional and toxicological importance in the wood samples. The analysis was performed in the Brazilian Synchrotron Light Source Laboratory, using a white beam for excitation and an Si(Li) detector for X-ray detection. In several samples were quantified P, K, Ca, Ti, Fe, Sr, Ba and Pb elements.

  10. Onset of collectivity in $^{96,98}$Sr studied via Coulomb excitation

    CERN Document Server

    Clement, E; Dijon, A; de France, G; Bastin, B; Blazhev, A; Bree, N; Butler, P; Delahaye, P; Ekstrom, A; Georgiev, G; Hasan, N; Iwanicki, J; Jenkins, D; Korten, W; Larsen, A C; Ljungvall, J; Moschner, K; Napiorkowski, P; Pakarinen, J; Petts, A; Renstrom, T; Seidlitz, M; Siem, S; Sotty, C; Srebrny, J; Stefanescu, I; Tveten, G M; Van de Walle, J; Warr, N; Wrzosek-Lipska, K; Zielinska, M; Bauer, C; Bruyneel, B; Butterworth, J; Fitzpatrick, C; Fransen, C; GernhäUser, R; Hess, H; Lutter, R; Marley, P; Reiter, P; Siebeck, B; Vermeulen, M; Wiens, A; De Witte, H

    2014-01-01

    A rapid onset of quadrupole deformation is known to occur around the neutron number 60 in the neutron-rich Zr and Sr isotopes. This shape change has made the neutron-rich A = 100 region an active area of experimental and theoretical studies for many decades now. We report in this contribution new experimental results in the neutron rich 96,98Sr investigated by safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility, CERN. Reduced transition probabilities and spectroscopic quadrupole moments have been extracted from the differential Coulomb excitation cross section supporting the scenario of shape coexistence/change at N=60. Future perspectives are presented including the recent experimental campaign performed at ILL-Grenoble.

  11. Angular momentum flux of nonparaxial acoustic vortex beams and torques on axisymmetric objects.

    Science.gov (United States)

    Zhang, Likun; Marston, Philip L

    2011-12-01

    An acoustic vortex in an inviscid fluid and its radiation torque on an axisymmetric absorbing object are analyzed beyond the paraxial approximation to clarify an analogy with an optical vortex. The angular momentum flux density tensor from the conservation of angular momentum is used as an efficient description of the transport of angular momentum. Analysis of a monochromatic nonparaxial acoustic vortex beam indicates that the local ratio of the axial (or radial) flux density of axial angular momentum to the axial (or radial) flux density of energy is exactly equal to the ratio of the beam's topological charge l to the acoustic frequency ω. The axial radiation torque exerted by the beam on an axisymmetric object centered on the beam's axis due to the transfer of angular momentum is proportional to the power absorbed by the object with a factor l/ω, which can be understood as a result of phonon absorption from the beam. Depending on the vortex's helicity, the torque is parallel or antiparallel to the beam's axis.

  12. The beam dump tunnels

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    In these images workers are digging the tunnels that will be used to dump the counter-circulating beams. Travelling just a fraction under the speed of light, the beams at the LHC will each carry the energy of an aircraft carrier travelling at 12 knots. In order to dispose of these beams safely, a beam dump is used to extract the beam and diffuse it before it collides with a radiation shielded graphite target.

  13. Parabolic scaling beams.

    Science.gov (United States)

    Gao, Nan; Xie, Changqing

    2014-06-15

    We generalize the concept of diffraction free beams to parabolic scaling beams (PSBs), whose normalized intensity scales parabolically during propagation. These beams are nondiffracting in the circular parabolic coordinate systems, and all the diffraction free beams of Durnin's type have counterparts as PSBs. Parabolic scaling Bessel beams with Gaussian apodization are investigated in detail, their nonparaxial extrapolations are derived, and experimental results agree well with theoretical predictions.

  14. Demonstration experiment of a laser synchrotron source for tunable, monochromatic x-rays at 500 eV

    Energy Technology Data Exchange (ETDEWEB)

    Ting, A.; Fischer, R.; Fisher, A. [Naval Research Lab., Washington, DC (United States)] [and others

    1995-12-31

    A Laser Synchrotron Source (LSS) was proposed to generate short-pulsed, tunable x-rays by Thomson scattering of laser photons from a relativistic electron beam. A proof-of-principle experiment was performed to generate x-ray photons of 20 eV. A demonstration experiment is being planned and constructed to generate x-ray photons in the range of {approximately}500 eV. Laser photons of {lambda}=1.06 {mu}m are Thomson backscattered by a 4.5 MeV electron beam which is produced by an S-band RF electron gun. The laser photons are derived from either (i) a 15 Joules, 3 nsec Nd:glass laser, (ii) the uncompressed nsec: pulse of the NRL table-top terawatt (T{sup 3}) laser, or (iii) the compressed sub-picosec pulse of the T{sup 3} laser. The RF electron gun is being constructed with initial operation using a thermionic cathode. It will be upgraded to a photocathode to produce high quality electron beams with high current and low emittance. The x-ray pulse structure consists of {approximately}10 psec within an envelope of a macropulse whose length depends on the laser used. The estimated x-ray photon flux is {approximately}10{sup 18} photons/sec, and the number of photons per macropulse is {approximately}10{sup 8}. Design parameters and progress of the experiment will be presented.

  15. Performance predictions for a laser intensified thermal beam for use in high resolution Focused Ion Beam instruments

    CERN Document Server

    Wouters, S H W; Notermans, R P M J W; Debernardi, N; Mutsaers, P H A; Luiten, O J; Vredenbregt, E J D

    2014-01-01

    Photo-ionization of a laser-cooled and compressed atomic beam from a high-flux thermal source can be used to create a high-brightness ion beam for use in Focus Ion Beam (FIB) instruments. Here we show using calculations and Doppler cooling simulations that an atomic rubidium beam with a brightness of $2.1 \\times 10^7 A/(m^2\\,sr\\,eV)$ at a current of 1 nA can be created using a compact 5 cm long 2D magneto-optical compressor which is more than an order of magnitude better than the current state of the art Liquid Metal Ion Source.

  16. A modified time-of-flight method for precise determination of high speed ratios in molecular beams

    Energy Technology Data Exchange (ETDEWEB)

    Salvador Palau, A.; Eder, S. D., E-mail: sabrina.eder@uib.no; Kaltenbacher, T.; Samelin, B.; Holst, B. [Department of Physics and Technology, University of Bergen, Allégaten 55, 5007 Bergen (Norway); Bracco, G. [Department of Physics and Technology, University of Bergen, Allégaten 55, 5007 Bergen (Norway); CNR-IMEM, Department of Physics, University of Genova, V. Dodecaneso 33, 16146 Genova (Italy)

    2016-02-15

    Time-of-flight (TOF) is a standard experimental technique for determining, among others, the speed ratio S (velocity spread) of a molecular beam. The speed ratio is a measure for the monochromaticity of the beam and an accurate determination of S is crucial for various applications, for example, for characterising chromatic aberrations in focussing experiments related to helium microscopy or for precise measurements of surface phonons and surface structures in molecular beam scattering experiments. For both of these applications, it is desirable to have as high a speed ratio as possible. Molecular beam TOF measurements are typically performed by chopping the beam using a rotating chopper with one or more slit openings. The TOF spectra are evaluated using a standard deconvolution method. However, for higher speed ratios, this method is very sensitive to errors related to the determination of the slit width and the beam diameter. The exact sensitivity depends on the beam diameter, the number of slits, the chopper radius, and the chopper rotation frequency. We present a modified method suitable for the evaluation of TOF measurements of high speed ratio beams. The modified method is based on a systematic variation of the chopper convolution parameters so that a set of independent measurements that can be fitted with an appropriate function are obtained. We show that with this modified method, it is possible to reduce the error by typically one order of magnitude compared to the standard method.

  17. Characterization of four-color multi-package white light-emitting diodes combined with various green monochromatic phosphor-converted light-emitting diodes

    Science.gov (United States)

    Oh, Ji Hye; Lee, Keyong Nam; Do, Young Rag

    2012-03-01

    In this study, several combinations of multi-package white light-emitting diodes (LEDs), which combine an InGaN blue LED with green, amber, and red phosphor-converted LEDs (pc-LEDs), were characterized by changing the peak wavelength of green pc-LEDs between 515nm and 560nm (515, 521, 530, 540, 550, 560nm) in color temperature of 6,500K and 3,500K. Various green monochromatic pc-LEDs were fabricated by capping a long-wave pass-filter (LWPF) on top of pc-LEDs to improve luminous efficacy and color purity. LWPF-capped green monochromatic pc-LED can address the drawback of green semiconductor-type III-V LED, such as low luminous efficacy in the region of green gap wavelength. Luminous efficacy and color rendering index (CRI) of multi-package white LEDs are compared with changing the driving current of individual LED in various multi-package white LEDs. This study provides a best combination of four-color multi-package white LEDs which has high luminous efficacy and good CRI.

  18. Facile Synthesis of SrCO3-Sr(OH2/PPy Nanocomposite with Enhanced Photocatalytic Activity under Visible Light

    Directory of Open Access Journals (Sweden)

    Alfredo Márquez-Herrera

    2016-01-01

    Full Text Available Pyrrole monomer was chemically polymerized onto SrCO3-Sr(OH2 powders to obtain SrCO3-Sr(OH2/polypyrrole nanocomposite to be used as a candidate for photocatalytic degradation of methylene blue dye (MB. The material was characterized by Fourier transform infrared (FTIR spectroscopy, UV/Vis spectroscopy, and X-ray diffraction (XRD. It was observed from transmission electronic microscopy (TEM analysis that the reported synthesis route allows the production of SrCO3-Sr(OH2 nanoparticles with particle size below 100 nm which were embedded within a semiconducting polypyrrole matrix (PPy. The SrCO3-Sr(OH2 and SrCO3-Sr(OH2/PPy nanocomposites were tested in the photodegradation of MB dye under visible light irradiation. Also, the effects of MB dye initial concentration and the catalyst load on photodegradation efficiency were studied and discussed. Under the same conditions, the efficiency of photodegradation of MB employing the SrCO3-Sr(OH2/PPy nanocomposite increases as compared with that obtained employing the SrCO3-Sr(OH2 nanocomposite.

  19. SR-71 Pilot Rogers E. Smith

    Science.gov (United States)

    1992-01-01

    Research pilot Rogers E. Smith is shown here in front of the SR-71 Blackbird he flew for NASA. Rogers was one of the two original NASA research pilots assigned to the SR-71 high speed research program at NASA's Ames-Dryden Flight Research Facility (later, Dryden Flight Research Center, Edwards, California. Smith has been a NASA research pilot at Dryden since 1982. Data from the SR-71 program will be used to aid designers of future supersonic aircraft and propulsion systems. The SR-71 is capable of flying more than 2200 mph (Mach 3+) and at altitudes of over 80,000 feet. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data

  20. Lattice design and beam dynamics studies of the high energy beam transport line in the RAON heavy ion accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyunchang, E-mail: hcjin@ibs.re.kr; Jang, Ji-Ho; Jang, Hyojae; Jeon, Dong-O

    2015-12-01

    In RAON heavy ion accelerator, beams generated by superconducting electron cyclotron resonance ion source (ECR-IS) or Isotope Separation On-Line (ISOL) system are accelerated by lower energy superconducting linac and high energy superconducting linac. The accelerated beams are used in the high energy experimental hall which includes bio-medical and muon-SR facilities, after passing through the high energy beam transport lines. At the targets of those two facilities, the stable and small beams meeting the requirements rigorously are required in the transverse plane. Therefore the beams must be safely sent to the targets and simultaneously satisfy the two requirements, the achromatic condition and the mid-plane symmetric condition, of the targets. For this reason, the lattice design of the high energy beam transport lines in which the long deflecting sections are included is considered as a significant issue in the RAON accelerator. In this paper, we will describe the calculated beam optics satisfying the conditions and present the result of particle tracking simulations with the designed lattice of the high energy beam transport lines in the RAON accelerator. Also, the orbit distortion caused by the machine imperfections and the orbit correction with correctors will be discussed.

  1. Beam diagnostics for low energy beams

    Directory of Open Access Journals (Sweden)

    J. Harasimowicz

    2012-12-01

    Full Text Available Low-energetic ion and antimatter beams are very attractive for a number of fundamental studies. The diagnostics of such beams, however, is a challenge due to low currents down to only a few thousands of particles per second and significant fraction of energy loss in matter at keV beam energies. A modular set of particle detectors has been developed to suit the particular beam diagnostic needs of the ultralow-energy storage ring (USR at the future facility for low-energy antiproton and ion research, accommodating very low beam intensities at energies down to 20 keV. The detectors include beam-profile monitors based on scintillating screens and secondary electron emission, sensitive Faraday cups for absolute intensity measurements, and capacitive pickups for beam position monitoring. In this paper, the design of all detectors is presented in detail and results from beam measurements are shown. The resolution limits of all detectors are described and options for further improvement summarized. Whilst initially developed for the USR, the instrumentation described in this paper is also well suited for use in other low-intensity, low-energy accelerators, storage rings, and beam lines.

  2. Memory resistive switching in CeO2-based film microstructures patterned by a focused ion beam

    DEFF Research Database (Denmark)

    Velichko, A.; Boriskov, P.; Grishin, A.

    2014-01-01

    Heteroepitaxial CeO2 (80 nm)/La0.5Sr0.5CoO3 (500 nm) film structure has been pulsed laser deposited on a sapphire substrate. The Ag/CeO2 microjunctions patterned by a focused ion beam on a La0.5Sr0.5CoO3 film exhibit reproducible reversible switching between a high resistance state (OFF...

  3. Sr fluxes and isotopic compositions of the eleven rivers originating from the Qinghai-Tibet Plateau and their contributions to 87Sr/86Sr evolution of seawater

    Institute of Scientific and Technical Information of China (English)

    WU WeiHua; YANG JieDong; XU ShiJin; LI GaoJun; YIN HongWei; TAO XianCong

    2009-01-01

    To evaluate influence of chemical weathering of the Qinghai-Tibet Plateau (QTP) on seawater 87Sr/66Srvariation, river water and sediment samples were collected, and their Sr concentrations and isotopic compositions analyzed, from the seven large rivers that originated from the QTP. By combining these with the data of the Ganges, Brahmaputra, Indus and Irrawaddy originated in the southern QTP, the total transported by the global rivers. The weighted mean 87Sr/86Sr is 0.71694, higher than the average value of the global rivers. The 87Srex (87Sr flux in excess of the seawater 87Sr/66Sr ratio) of the Chinese seven QTP, and the Ganges-Brahmaputra system accounts for 86%. We assume that the QTP rivers have no strontium contributions to the oceans before -40 Ma and the Sr fluxes of the global rivers, except the QTP eleven rivers, are constant, then a maximum linear increase in Sr fluxes of the QTP rivers from zero to the modern value in response to tectonic uplift can explain -69% increase of seawater 87Sr/86Sr over the past -40 Ma and the remainder of 31% is perhaps provided from other factors.

  4. SR 97 - Identification and structuring of process

    Energy Technology Data Exchange (ETDEWEB)

    Pers, K.; Skagius, K.; Soedergren, S.; Wiborgh, M. [Kemakta Konsult AB, Stockholm (Sweden); Hedin, A.; Moren, L.; Sellin, P.; Stroem, A. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Pusch, R. [Geodevelopment AB, Lund (Sweden); Bruno, J. [QuantiSci SL, Barcelona (Spain)

    1999-12-01

    This report documents work conducted in recent years to identify processes and interactions of importance to the evaluation of long-term safety of a KBS 3 type deep repository for spent nuclear fuel. Previous, partly undocumented work regarding interaction matrices is described as well as the THMC diagrams that have been used in the safety assessment SR 97. The coupling between the two sources of information is documented in a database. In the same database, the interaction matrices are briefly documented, while the processes in the THMC diagrams are more thoroughly documented in a special so called Process Report, which forms an important supporting document for SR 97.

  5. 87Sr/ 86Sr, 143Nd/ 144Nd and REEs in Silurian phosphatic fossils

    Science.gov (United States)

    Bertram, C. J.; Elderfield, H.; Aldridge, R. J.; Conway Morris, S.

    1992-09-01

    The feasibility of using the chemistry of phosphatic fossil material to trace palaeo-seawater composition for the Silurian has been evaluated. Contrary to Recent material, fossil fish are shown to be unreliable for Sr isotope stratigraphy. Conodonts, however, may be used by employing 0.2M HNO 3 dissolution, except for samples showing degrees of thermal maturation greater than colour alteration index (CAI) values of 2.5. Samples from the same stratigraphic levels from the U.K., Czechoslovakia, Gotland and the U.S.A. gave similar 87Sr/ 86Sr ratios, suggesting that they have recorded the original seawater value. Significant inter-specific differences occur in REE concentrations and Nd isotopic compositions of conodont elements, and Ce and Eu anomalies vary with REE content. This suggests that artefacts are introduced at the same time that large amounts of REEs are incorporated into the apatite. Preliminary results for the Sr isotopic composition of Silurian seawater are presented. Values are generally lower than previously suggested, showing an increase in 87Sr/ 86Sr from ˜ 0.70825 at 435 Ma rising to ˜ 0.70875 at 418 Ma and levelling off in the Late Silurian. The overall rate of increase in seawater ratio is about2-3 × 10 -5 Ma -1 and can be accounted for by the widespread decrease in volcanism compared with the Ordovician; a proportionally greater flux of Sr to the oceans from continental erosion of only ˜ 10% would account for the long-term increase in seawater 87Sr/ 86Sr ratio throughout the Silurian.

  6. FEP report for the safety assessment SR-Site

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

  7. Analysis of coupled Sr/Ca and 87Sr/ 86Sr variations in enamel using laser-ablation tandem quadrupole-multicollector ICPMS

    Science.gov (United States)

    Balter, Vincent; Telouk, Philippe; Reynard, Bruno; Braga, José; Thackeray, Francis; Albarède, Francis

    2008-08-01

    We present in this study results obtained with a laser-ablation coupled with both a quadrupole and a multi-collector ICPMS. The simultaneous in situ Sr/Ca and 87Sr/ 86Sr measurements along growth profiles in enamel allows the concomitant diet and migration patterns in mammals to be reconstructed. Aliquots of the powdered international standard NIST "SRM1400 Bone Ash" with certified Sr and Ca contents, was sintered at high pressure and temperature and was adopted as the reference material for external reproducibility and calibration of the results. A total of 145 coupled elemental and isotopic measurements of herbivores enamel from the Kruger National Park, South Africa, gives intra-tooth Sr/Ca and 87Sr/ 86Sr variations that are well larger than external reproducibility. Sr/Ca profiles systematically decrease from the dentine-enamel junction to the outer enamel whereas 87Sr/ 86Sr profiles exhibit variable patterns. Using a simple geometric model of hypsodont teeth growth, we demonstrate that a continuous recording of the 87Sr/ 86Sr variations can be reconstructed in the tooth length axis. This suggests that the mobility of a mammal can be reconstructed over a period of more than a year with a resolution of a ten of days, by sampling enamel along growth profiles. Our geometric model of hypsodont teeth growth predicts that an optimal distance between two successive profiles is equal to the enamel thickness. However, this model does not apply to the Sr/Ca signal which is likely to be altered during the enamel maturation stage due to differential maturation processes along enamel thickness. Here, the observed constant decreases of the Sr/Ca ratios in the ungulates of Kruger National Park suggests that they did not changed of diet, while some of them were migrating.

  8. A New High-intensity, Low-momentum Muon Beam for the Generation of Low-energy Muons at PSI

    Energy Technology Data Exchange (ETDEWEB)

    Prokscha, T., E-mail: thomas.prokscha@psi.ch; Morenzoni, E.; Deiters, K.; Foroughi, F.; George, D.; Kobler, R.; Vrankovic, V. [Paul Scherrer Institute, PSI (Switzerland)

    2004-12-15

    At the Paul Scherrer Institute (PSI, Villigen, Switzerland) a new high-intensity muon beam line with momentum p < 40 MeV/c is currently being commissioned. The beam line is especially designed to serve the needs of the low-energy, polarized positive muon source (LE-{mu}{sup +}) and LE-{mu} SR spectrometer at PSI. The beam line replaces the existing {mu} E4 muon decay channel. A large acceptance is accomplished by installing two solenoidal magnetic lenses close to the muon production target E that is hit by the 590-MeV PSI proton beam. The muons are then transported by standard large aperture quadrupoles and bending magnets to the experiment. Several slit systems and an electrostatic separator allow the control of beam shape, momentum spread, and to reduce the background due to beam positrons or electrons. Particle intensities of up to 3.5 x 10{sup 8} {mu}{sup +}/s and 10{sup 7} {mu}{sup -}/s are expected at 28 MeV/c beam momentum and 1.8 mA proton beam current. This will translate into a LE-{mu}{sup +} rate of 7,000/s being available at the LE-{mu} SR spectrometer, thus achieving {mu}{sup +} fluxes, that are comparable to standard {mu} SR facilities.

  9. Pyramid beam splitter

    Science.gov (United States)

    McKeown, Mark H.; Beason, Steven C.; Fairer, George

    1992-01-01

    The apparatus of the present invention provides means for obtaining accurate, dependable, measurement of bearings and directions for geologic mapping in subterranean shafts, such as, for example, nuclear waste storage investigations. In operation, a laser beam is projected along a reference bearing. A pyramid is mounted such that the laser beam is parallel to the pyramid axis and can impinge on the apex of the pyramid thus splitting the beam several ways into several beams at right angles to each other and at right angles to the reference beam. The pyramid is also translatable and rotatable in a plane perpendicular to the reference beam.

  10. Low current beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saint, A.; Laird, J.S.; Bardos, R.A.; Legge, G.J.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Nishijima, T.; Sekiguchi, H. [Electrotechnical Laboratory, Tsukuba (Japan).

    1993-12-31

    Since the development of Scanning Transmission Microscopy (STIM) imaging in 1983 many low current beam techniques have been developed for the scanning (ion) microprobe. These include STIM tomography, Ion Beam Induced Current, Ion Beam Micromachining and Microlithography and Ionoluminense. Most of these techniques utilise beam currents of 10{sup -15} A down to single ions controlled by beam switching techniques This paper will discuss some of the low beam current techniques mentioned above, and indicate, some of their recent applications at MARC. A new STIM technique will be introduced that can be used to obtain Z-contrast with STIM resolution. 4 refs., 3 figs.

  11. REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.

    Energy Technology Data Exchange (ETDEWEB)

    FOERSTER,C.

    1999-05-01

    Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam line locations so that the monochromator, mirror box or sample chamber may be used in a helium atmosphere or rough vacuum. The window separates ring vacuum from the environment of the downstream beam line components. The stored beam lifetime in the storage rings and the maintenance of desirable reflection properties of optical surfaces depend upon hydrocarbon-free, ultra-high vacuum systems. Storage ring vacuum systems will operate at pressures of {approximately} 1 x 10{sup {minus}10} Torr without beam and {approximately} 1 x 10{sup {minus}9} Torr with beam. Systems are free of hydrocarbons in the sense that no pumps, valves, etc. containing organics are used. Components are all-metal, chemically cleaned and bakeable. To the extent that beam lines share a common vacuum with the storage ring, the same criteria will hold for beam line components. The design philosophy for NSLS beam lines is to use all-metal, hydrocarbon-free front end components and recommend that experimenters use this approach for common vacuum hardware

  12. Radionuclide transport report for the safety assessment SR-Site

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    This document compiles radionuclide transport calculations of a KBS-3 repository for the safety assessment SR-Site. The SR-Site assessment supports the licence application for a final repository at Forsmark, Sweden

  13. Target and orbit feedback simulations of a muSR beamline at BNL

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W. W. [Residence, 25 Rhododendron Circle, Asheville, NC (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pile, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. The use of the AGS complex at BNL has been explored for a muSR facility previously. Here we report simulations of a beamline with a target inside a solenoidal field, and of an orbit feed-back system with single muon beam positioning monitors based on technology available today

  14. Target and orbit feedback simulations of a muSR beamline at BNL

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W. W. [Residence, 25 Rhododendron Circle, Asheville, NC (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pile, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. The use of the AGS complex at BNL has been explored for a muSR facility previously. Here we report simulations of a beamline with a target inside a solenoidal field, and of an orbit feed-back system with single muon beam positioning monitors based on technology available today

  15. Beam-Beam Experience at KEKB

    Energy Technology Data Exchange (ETDEWEB)

    Bane, Karl LF

    2002-11-11

    KEKB has achieved the peak luminosity of 4.1 x 10{sup 33} cm{sup -2} sec{sup -1} and the present capability for delivering integrated luminosity is 224 pb{sup -1}/day. This paper describes (1) the recent performance and the problems of KEKB and (2) the comparison of beam-beam simulations with experiments at KEKB.

  16. T10 Beam Studies & Beam Simulation

    CERN Document Server

    Bergmann, Michael Georges; Van Dijk, Maarten; CERN. Geneva. EN Department

    2017-01-01

    In order to test detector components before their installation in actual experiments, one uses test beams in which one can control particle typ, momentum and size to high degree. For this project the focus of a secondary beam at T10 in the East Area at CERN was analysed using an AZALEA telescope from DESY.

  17. Beam-beam issues in asymmetric colliders

    Energy Technology Data Exchange (ETDEWEB)

    Furman, M.A.

    1992-07-01

    We discuss generic beam-beam issues for proposed asymmetric e{sup +}- e{sup -} colliders. We illustrate the issues by choosing, as examples, the proposals by Cornell University (CESR-B), KEK, and SLAC/LBL/LLNL (PEP-II).

  18. Beam Dynamics and Beam Losses - Circular Machines

    CERN Document Server

    Kain, V

    2016-01-01

    A basic introduction to transverse and longitudinal beam dynamics as well as the most relevant beam loss mechanisms in circular machines will be presented in this lecture. This lecture is intended for physicists and engineers with little or no knowledge of this subject.

  19. A change of Sr cycle in the Ediacaran Ocean: Evidence from radiogenic and stable isotope ratios of Sr, in Three Gorges, South China.

    Science.gov (United States)

    Sawaki, Y.; Tahata, M.; Komiya, T.; Maruyama, S.

    2008-12-01

    Objective. To decode surface environmental changes and patterns of biological evolution during the Ediacaran Methods employed. We undertook deep drilling in Three Gorges area in South China to obtain continuous and fresh samples without surface alteration and oxidation. 87Sr/86Sr and 88Sr/86Sr ratios of the fresh carbonate rocks were measured with multiple collector-inductively coupled plasma-mass spectrometric techniques. We discuss the surface environmental change in the Ediacaran by comparing the Sr isotope ratios with 13C/12C and 18O/16O. Result. The chemostratigraphy of 87Sr/86Sr ratios of the drilled samples displays a smooth curve and two large positive shifts in the Ediacaran. The combination of the detailed chemostratigraphies of 13C/12C, 18O/16O, and 87Sr/86Sr enable us to find connections among them and indicates that the first large positive shift of 87Sr/86Sr is slightly preceded by negative 13C/12C and positive 18O/16O excursions. The second large positive shift of 87Sr/86Sr is simultaneous with positive 13C/12C shift and clearly precedes next negative 13C/12C excursion. Considering Mn content and Fe content of carbonate rocks, which respond to redox in the ocean, the first positive shift can be explained by Gaskiers glaciation. Exposed surface of continental crust were increased by regression accompanied by Gaskiers glaciation and enhanced weathering rate by rivers increased seawater 87Sr/86Sr. The second positive shift of 87Sr/86Sr is a long-term fluctuation. We speculate enhanced weathering rate, resulting from convergence of Gondwana supercontinent, as a cause of the second positive shift of 87Sr/86Sr. Chemostratigraphy of 88Sr/86Sr also displays a smooth curve. Before Gaskiers glaciation, 88Sr/86Sr curve have a negative correlation with 87Sr/86Sr fluctuation. We interpret that this negative correlation is explained by mass-dependent fractionation. When Sr are increased in ocean (high 87Sr/86Sr), 86Sr are selectively taken in carbonate (low 88Sr

  20. 习水地区不同类型水主要离子及Sr2+、ρ(Sr)/ρ(Ca)、ρ(Sr)/ρ(Mg)组成特征%Composition Characteristics of Major Ions and ρ (Sr2 +) ,ρ (Sr)/ρ (Ca),ρ (Sr)/ρ (Mg) Value in Different Types of Water in Xishui

    Institute of Scientific and Technical Information of China (English)

    黄奇波; 覃小群; 唐建生; 苏春田

    2012-01-01

    After sampling and analyzing major ions concentration and ρ(Sr2 + ) ,ρ(Sr)/ρ(Ca) ,ρ(Sr)/ρ(Mg) value in different types of water from Xishui basin, low major ions concentration is found in bedrock fracture water. But TDS content and pH value are higher than in the karst water. The concentration of Ca2 +, HCO3-, TDS and the value of ρ( Sr)/ρ( Ca) and ρ( Sr)/ρ( Mg) in outlet water of under ground river are as the value in limestone water ture dolomite water, bedrock fracture water, and rainwater, reflecting that the underground river water is the mixtave of these four types of water. The underground water flowing over different rock formation has different value of ρ(Sr2 + ) , ρ(Sr)/ρ(Ca) , ρ( Sr)/ρ( Mg). Generally speaking, the bedrock fracture water flowing over sandstone formation contains low ρ( Sr2 + ) but high ρ( Sr ) /ρ(Ca ) ,ρ( Sr) /ρ( Mg ). Recharged by the water from limestone or coal measure formation, the fracture water of sandstone has high ρ(Sr2+ ) ,ρ(Sr)/ ρ(Ca) and ρ(Sr)/ρ(Mg). The value of ρ(Sr)/ρ(Ca) ,ρ(Sr)/ρ(Mg) is low in recharge area of karst water, but high in runoff and discharge area, yet highest in slow runoff area, not affected by environmental pollution, ref-leciting the formation environment of karst water.%通过对习水地区不同类型水的主要阴阳离子及Sr2+、ρ(Sr)/ρ(Ca)、ρ(Sr)/ρ(Mg)组成分析,发现水中各种主要离子及TDS含量基岩裂隙水小于岩溶水,ρH则相反.地下河出口水的Ca2+、HCO3-、TDS浓度及ρ(Sr)/ρ (Ca)、ρ(Sr)/ρ (Mg)值均位于灰岩水、白云岩水、基岩裂隙水、雨水之间,反映出地下河水是由这4种水混合而成.流经不同岩层的地下水具有不同的Sr2+、ρ(Sr)/ρ (Ca)、ρ(Sr)/ρ(Mg)值.一般来说,流经砂岩层的基岩裂隙水Sr2+含量低,而ρ(Sr)/ρ (Ca)、ρ(Sr)/ρ (Mg)值较高,当砂岩中的基岩裂隙水受到灰岩水或煤系地层水补给时,其Sr2+、ρ(sr)/ρ (Ca)、ρ(Sr)/ρ(Mg)值均较高;岩溶

  1. Successful Beam-Beam Tuneshift Compensation

    Energy Technology Data Exchange (ETDEWEB)

    Bishofberger, Kip Aaron [Univ. of California, Los Angeles, CA (United States)

    2005-01-01

    The performance of synchrotron colliders has been limited by the beam-beam limit, a maximum tuneshift that colliding bunches could sustain. Due to bunch-to-bunch tune variation and intra-bunch tune spread, larger tuneshifts produce severe emittance growth. Breaking through this constraint has been viewed as impossible for several decades. This dissertation introduces the physics of ultra-relativistic synchrotrons and low-energy electron beams, with emphasis placed on the limits of the Tevatron and the needs of a tuneshift-compensation device. A detailed analysis of the Tevatron Electron Lens (TEL) is given, comparing theoretical models to experimental data whenever possible. Finally, results of Tevatron operations with inclusion of the TEL are presented and analyzed. It is shown that the TEL provides a way to shatter the previously inescapable beam-beam limit.

  2. Investidura como Doctor Sr. D. Luigi Ferrajoli

    OpenAIRE

    Ferrajoli, Luigi

    2009-01-01

    ÍNDICE: Laudatio Prof. Dr. D. Luis Prieto Sanchís Lección Magistral: La democracia política y su crisis actual Prof. Dr. D. Luigi Ferrajoli Salutación Excmo. Sr. Rector Magnífico, D. Ernesto Martínez Ataz Galeria fotográfica

  3. X-ray instrumentation for SR beamlines

    CERN Document Server

    Kovalchuk, M V; Zheludeva, S I; Aleshko-Ozhevsky, O P; Arutynyan, E H; Kheiker, D M; Kreines, A Y; Lider, V V; Pashaev, E M; Shilina, N Y; Shishkov, V A

    2000-01-01

    The main possibilities and parameters of experimental X-ray stations are presented: 'Protein crystallography', 'X-ray structure analysis', 'High-precision X-ray optics', 'X-ray crystallography and material science', 'X-ray topography', 'Photoelectron X-ray standing wave' that are being installed at Kurchatov SR source by A.V. Shubnikov Institute of Crystallography.

  4. BEAM PIPE IS INSTALLED

    CERN Multimedia

    The installation of the central section of the beam pipe into the heart of the  CMS was completed by 23 April. All the beam pipe elements have been successfully vacuum-tested and the bakeout started.  

  5. Beam Loss in Linacs

    CERN Document Server

    Plum, M A

    2016-01-01

    Beam loss is a critical issue in high-intensity accelerators, and much effort is expended during both the design and operation phases to minimize the loss and to keep it to manageable levels. As new accelerators become ever more powerful, beam loss becomes even more critical. Linacs for H- ion beams, such as the one at the Oak Ridge Spallation Neutron Source, have many more loss mechanisms compared to H+ (proton) linacs, such as the one being designed for the European Spallation Neutron Source. Interesting H- beam loss mechanisms include residual gas stripping, H+ capture and acceleration, field stripping, black-body radiation and the recently discovered intra-beam stripping mechanism. Beam halo formation, and ion source or RF turn on/off transients, are examples of beam loss mechanisms that are common for both H+ and H- accelerators. Machine protection systems play an important role in limiting the beam loss.

  6. High energy beam lines

    Science.gov (United States)

    Marchetto, M.; Laxdal, R. E.

    2014-01-01

    The ISAC post accelerator comprises an RFQ, DTL and SC-linac. The high energy beam lines connect the linear accelerators as well as deliver the accelerated beams to two different experimental areas. The medium energy beam transport (MEBT) line connects the RFQ to the DTL. The high energy beam transport (HEBT) line connects the DTL to the ISAC-I experimental stations (DRAGON, TUDA-I, GPS). The DTL to superconducting beam (DSB) transport line connects the ISAC-I and ISAC-II linacs. The superconducting energy beam transport (SEBT) line connects the SC linac to the ISAC-II experimental station (TUDA-II, HERACLES, TIGRESS, EMMA and GPS). All these lines have the function of transporting and matching the beams to the downstream sections by manipulating the transverse and longitudinal phase space. They also contain diagnostic devices to measure the beam properties.

  7. Vortices in Gaussian beams

    CSIR Research Space (South Africa)

    Roux, FS

    2009-01-01

    Full Text Available . Gaussian beams with vortex dipoles CSIR National Laser Centre – p.2/30 Gaussian beam notation Gaussian beam in normalised coordinates: g(u, v, t) = exp ( −u 2 + v2 1− it ) u = xω0 v = yω0 t = zρ ρ = piω20 λ ω0 — 1/e2 beam waist radius; ρ— Rayleigh range ω ω...(z) 0 x z Rayleigh range Beam waist ρ ρ Rayleigh range CSIR National Laser Centre – p.3/30 Gaussian beam Gaussian beam in terms of amplitude and phase g(u, v, t) = exp ( −u 2 + v2 1 + t2 ) exp ( − it(u 2 + v2) 1 + t2 ) Normalised beam radius: √ 1 + t2...

  8. Strontium adsorption and penetration in kaolinite at low Sr

    NARCIS (Netherlands)

    Ning, Zigong; Ishiguro, Munehide; Koopal, Luuk K.; Sato, Tsutomu; Kashiwagi, Junichi

    2017-01-01

    Behavior of radioactive strontium (Sr2+) in contaminated soils is an important issue in relation to nuclear power plant accidents. The Sr2+ adsorption on kaolinite and its migration in a kaolinite soil were investigated because toxic effects of radioactive Sr2+ have been found to be very severe for

  9. Empirical model for controlling beam-beam effects in ISABELLE

    Energy Technology Data Exchange (ETDEWEB)

    Parzen, G

    1980-01-01

    The beam-beam interaction may limit the beam intensity in ISABELLE. Although considerable progress has been made in understanding the beam-beam interaction, there appears to be no reliable method at present for computing the effects of the beam-beam interaction. The steps taken at ISABELLE to limit beam-beam effects are based largely on the experience accumulated at the ISR. At the ISR, the beam-beam effects do not appear to be large, and the beam intensity at the ISR does not appear to be limited by beam-beam effects. The beam-beam effects may be much stronger in ISABELLE because of factors like higher intensity and stronger non-linearities.

  10. Electron Beam Ion Sources

    OpenAIRE

    Zschornacka, G.; Schmidt, M.; Thorn, A.

    2014-01-01

    Electron beam ion sources (EBISs) are ion sources that work based on the principle of electron impact ionization, allowing the production of very highly charged ions. The ions produced can be extracted as a DC ion beam as well as ion pulses of different time structures. In comparison to most of the other known ion sources, EBISs feature ion beams with very good beam emittances and a low energy spread. Furthermore, EBISs are excellent sources of photons (X-rays, ultraviolet, extreme ultraviole...

  11. Electron beam focusing system

    Energy Technology Data Exchange (ETDEWEB)

    Dikansky, N.; Nagaitsev, S.; Parkhomchuk, V.

    1997-09-01

    The high energy electron cooling requires a very cold electron beam. Thus, the electron beam focusing system is very important for the performance of electron cooling. A system with and without longitudinal magnetic field is presented for discussion. Interaction of electron beam with the vacuum chamber as well as with the background ions and stored antiprotons can cause the coherent electron beam instabilities. Focusing system requirements needed to suppress these instabilities are presented.

  12. Beam Dynamics for ARIA

    CERN Document Server

    Ekdahl, Carl

    2015-01-01

    Beam dynamics issues are assessed for a new linear induction electron accelerator being designed for flash radiography of large explosively driven hydrodynamic experiments. Special attention is paid to equilibrium beam transport, possible emittance growth, and beam stability. It is concluded that a radiographic quality beam will be produced possible if engineering standards and construction details are equivalent to those on the present radiography accelerators at Los Alamos.

  13. Beam Dynamics for ARIA

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Carl August Jr. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-14

    Beam dynamics issues are assessed for a new linear induction electron accelerator being designed for flash radiography of large explosively driven hydrodynamic experiments. Special attention is paid to equilibrium beam transport, possible emittance growth, and beam stability. It is concluded that a radiographic quality beam will be produced possible if engineering standards and construction details are equivalent to those on the present radiography accelerators at Los Alamos.

  14. Interferometric measurement of the beam size in the compact storage ring

    CERN Document Server

    Yamamoto, Y; Mitsuhashi, T; Amano, D; Iwasaki, H

    2001-01-01

    The beam size in the compact superconducting storage ring AURORA at Ritsumeikan University was measured using the SR-interferometer. The radiation beam from the bending magnet was passed through the double-slit and an interferogram formed in the visible spectral region was recorded using a CCD camera. The spatial coherence of the beam was derived from the analysis of the intensity profile and its dependence on the spatial frequency has yielded the beam size of 10.5 mu m in the vertical direction. It is unexpectedly small, indicating a high accuracy in the design of magnetic field in the magnet. The beam size could be varied by applying an rf kick electric field and the dependence of the beam lifetime on the size has shown that it is primarily governed by the Tauschek effect.

  15. Coherent convergent-beam time-resolved X-ray diffraction

    Science.gov (United States)

    Spence, John C. H.; Zatsepin, Nadia A.; Li, Chufeng

    2014-01-01

    The use of coherent X-ray lasers for structural biology allows the use of nanometre diameter X-ray beams with large beam divergence. Their application to the structure analysis of protein nanocrystals and single particles raises new challenges and opportunities. We discuss the form of these coherent convergent-beam (CCB) hard X-ray diffraction patterns and their potential use for time-resolved crystallography, normally achieved by Laue (polychromatic) diffraction, for which the monochromatic laser radiation of a free-electron X-ray laser is unsuitable. We discuss the possibility of obtaining single-shot, angle-integrated rocking curves from CCB patterns, and the dependence of the resulting patterns on the focused beam coordinate when the beam diameter is larger or smaller than a nanocrystal, or smaller than one unit cell. We show how structure factor phase information is provided at overlapping interfering orders and how a common phase origin between different shots may be obtained. Their use in refinement of the phase-sensitive intensity between overlapping orders is suggested. PMID:24914153

  16. Coherent convergent-beam time-resolved X-ray diffraction.

    Science.gov (United States)

    Spence, John C H; Zatsepin, Nadia A; Li, Chufeng

    2014-07-17

    The use of coherent X-ray lasers for structural biology allows the use of nanometre diameter X-ray beams with large beam divergence. Their application to the structure analysis of protein nanocrystals and single particles raises new challenges and opportunities. We discuss the form of these coherent convergent-beam (CCB) hard X-ray diffraction patterns and their potential use for time-resolved crystallography, normally achieved by Laue (polychromatic) diffraction, for which the monochromatic laser radiation of a free-electron X-ray laser is unsuitable. We discuss the possibility of obtaining single-shot, angle-integrated rocking curves from CCB patterns, and the dependence of the resulting patterns on the focused beam coordinate when the beam diameter is larger or smaller than a nanocrystal, or smaller than one unit cell. We show how structure factor phase information is provided at overlapping interfering orders and how a common phase origin between different shots may be obtained. Their use in refinement of the phase-sensitive intensity between overlapping orders is suggested. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. A Quantum Gas Jet for Non-Invasive Beam Profile Measurement

    CERN Document Server

    Holzer, EB; Lefevre, T; Tzoganis, V; Welsch, C; Zhang, H

    2014-01-01

    A novel instrument for accelerator beam diagnostics is being developed by using De Broglie-wave focusing to create an ultra-thin neutral gas jet. Scanning the gas jet across a particle beam while measuring the interaction products, the beam profile can be measured. Such a jet scanner will provide an invaluable diagnostic tool in beams which are too intense for the use of wire scanners, such as the proposed CLIC Drive Beam. In order to create a sufficiently thin jet, a focusing element working on the de Broglie wavelength of the Helium atom has been designed. Following the principles of the Photon Sieve, we have constructed an Atomic Sieve consisting of 5230 nano-holes etched into a thin film of silicon nitride. When a quasi-monochromatic Helium jet is incident on the sieve, an interference pattern with a single central maximum is created. The stream of Helium atoms passing through this central maximum is much narrower than a conventional gas jet. The first experiences with this device are presented here, alon...

  18. Nuclear structure investigations of 84Sr and 86Sr using γ-ray spectroscopic methods

    Science.gov (United States)

    Duckwitz, H.; Petkov, P.; Thomas, T.; Ahn, T.; Blazhev, A.; Cooper, N.; Fransen, C.; Hinton, M.; Ilie, G.; Jolie, J.; Werner, V.

    2017-09-01

    To investigate the low-spin structure of 84Sr and 86Sr, two fusion-evaporation experiments using the (p,2n) reaction have been performed. The data have been evaluated in terms of γ-ray spectroscopy, i.e. the level scheme was built up, branching intensities were determined, nuclear state spin and parity assignments were made after γγ angular correlation analyses. The previously known level scheme information was extended. In addition, lifetimes were determined by means of the Doppler Shift Attenuation Method (DSAM). In 86Sr, a new method for lifetime determinations, the Spectral Difference Method (SDM), was applied for the first time. In cases where all necessary input variables were known, reduced transition strengths were calculated with Monte Carlo simulated probability density functions. It is stressed that linear error propagation for the calculated errors of reduced transition strengths is not universally applicable. As both nuclei lie in the vicinity of the N=50 neutron shell closure and on a possible proton subshell closure of the 2p3/2 orbital at Z=38, Nuclear Shell Model calculations for 84Sr, 86Sr, and 88Sr have been performed in the truncated (2p3/2, 1f5/2, 2p1/2, 1g9/2) model space for protons and neutrons with the empirical JUN45 residual interaction. The comparison between experimental results and theoretical predictions show a large degree of consistency.

  19. Beam injection into RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W.; Hahn, H.; MacKay, W.W.; Satogata, T.; Tsoupas, N.; Zhang, W.

    1997-07-01

    During the RHIC sextant test in January 1997 beam was injected into a sixth of one of the rings for the first time. The authors describe the injection zone and its bottlenecks. They report on the commissioning of the injection system, on beam based measurements of the kickers and the application program to steer the beam.

  20. An Electromagnetic Beam Converter

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to an electromagnetic beam converter and a method for conversion of an input beam of electromagnetic radiation having a bell shaped intensity profile a(x,y) into an output beam having a prescribed target intensity profile l(x',y') based on a further development...

  1. Beam Optics for FCC-ee Collider Ring

    CERN Document Server

    Oide, Katsunobu; Aumon, S; Benedikt, M; Blondel, A; Bogomyagkov, A V; Boscolo, M; Burkhardt, H; Cai, Y; Doblhammer, A; Haerer, B; Holzer, B; Koop, I; Koratzinos, M; Jowett, John M; Levichev, E B; Medina, L; Ohmi, K; Papaphilippou, Y; Piminov, P A; Shatilov, D N; Sinyatkin, S V; Sullivan, M; Wenninger, J; Wienands, U; Zhou, D; Zimmermann, F

    2017-01-01

    A beam optics scheme has been designed [ 1 ] for the Future Circular Collider- e + e − (FCC-ee). The main characteristics of the design are: beam energy 45 to 175 GeV, 100 km circumference with two interaction points (IPs) per ring, horizontal crossing angle of 30 mrad at the IP and the crab-waist scheme [ 2 ] with local chromaticity correction. The crab-waist scheme is implemented within the local chromaticity correction system without additional sextupoles, by reducing the strength of one of the two sextupoles for vertical chromatic correction at each side of the IP. So- called “tapering" of the magnets is applied, which scales all fields of the magnets according to the local beam energy to compensate for the effect of synchrotron radiation (SR) loss along the ring. An asymmetric layout near the interaction region reduces the critical energy of SR photons on the incoming side of the IP to values below 100 keV, while matching the geometry to the beam line of the FCC proton collider (FCC-hh) [ 3 ] as clos...

  2. Halo formation from mismatched beam-beam interactions

    Energy Technology Data Exchange (ETDEWEB)

    Qiang, Ji

    2003-05-23

    In this paper, we report on the halo formation and emittance growth driven by a parametric resonance during mismatched beam-beam collisions. In the regime of the weak-strong beam-beam interaction, if two beams have the same machine tunes, on-axis head-on collisions between a mismatched strong beam and a weak beam will not cause the formation of halo. However, if the two beams collide with an initial offset, the beam-beam force from the mismatched strong beam can cause halo formation and emittance growth in the weak beam. Meanwhile, if two beams have different machine tunes, for opposite charged colliding beams, when the machine tune of the weak beam is smaller than that of strong beam, there is emittance growth in the weak beam. When the machine tune of the weak beam is larger than that of the strong beam, there is little emittance growth. In the regime of strong-strong beam-beam interaction, halo is formed in both beams even when the two beams collide head-on on the axis with equal machine tunes. This puts a strong requirement for a good beam match during the injection to colliders in order to avoid the emittance growth.

  3. Monochromatic excimer light versus combination of topical steroid with vitamin D3 analogue in the treatment of nonsegmental vitiligo: a randomized blinded comparative study.

    Science.gov (United States)

    Abdel Latif, Azmy Ahmed; Ibrahim, Shady Mahmoud Attia

    2015-01-01

    Vitiligo is a difficult disease to treat, socially stigmatizing its patients. Monochromatic excimer light (MEL) was developed for use in dermatology and adapted for the treatment of vitiligo. Comparing the efficacy of MEL versus topical combination therapy of vitamin D3 analogue and steroid in the treatment of nonsegmental vitiligo. Forty-four patients with localized and stable nonsegmental vitiligo participated in the present study. In each patient, two lesions were selected and divided randomly into two groups, group A was treated with daily topical combination of calcipotriol and betamethasone and group B was treated with biweekly sessions of MEL for 3 months. Efficacy based on repigmentation percentages were blindly evaluated by two independent physicians and patient's satisfaction. There was significant improvement in both treatment modalities at the end of the study, but without significant differences in both groups. There was a significant difference between both groups regarding the onset of repigmentation (p-value vitiligo.

  4. A possibility of parallel and anti-parallel diffraction measurements on neutron diffractometer employing bent perfect crystal monochromator at the monochromatic focusing condition

    Indian Academy of Sciences (India)

    Yong Nam Choi; Shin Ae Kim; Sung Kyu Kim; Sung Baek Kim; Chang-Hee Lee; Pivel Mikula

    2004-07-01

    In a conventional diffractometer having single monochromator, only one position, parallel position, is used for the diffraction experiment (i.e. detection) because the resolution property of the other one, anti-parallel position, is very poor. However, a bent perfect crystal (BPC) monochromator at monochromatic focusing condition can provide a quite flat and equal resolution property at both parallel and anti-parallel positions and thus one can have a chance to use both sides for the diffraction experiment. From the data of the FWHM and the / measured on three diffraction geometries (symmetric, asymmetric compression and asymmetric expansion), we can conclude that the simultaneous diffraction measurement in both parallel and anti-parallel positions can be achieved.

  5. Aspects of the SrO-CuO-TiO2 Ternary System Related to the Deposition of SrTiO3 and Copper-Doped SrTiO3 Thin-Film Buffer Layers

    Energy Technology Data Exchange (ETDEWEB)

    A. Ayala

    2004-12-20

    YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) coated conductors are promising materials for large-scale superconductivity applications. One version of a YBCO coated conductor is based on ion beam assisted deposition (IBAD) of magnesium oxide (MgO) onto polycrystalline metal substrates. SrTiO{sub 3} (STO) is often deposited by physical vapor deposition (PVD) methods as a buffer layer between the YBCO and IBAD MgO due to its chemical stability and lattice mismatch of only {approx}1.5% with YBCO. In this work, some aspects of the stability of STO with respect to copper (Cu) and chemical solution deposition of STO on IBAD MgO templates were examined. Solubility limits of Cu in STO were established by processing Cu-doped STO powders by conventional bulk preparation techniques. The maximum solubility of Cu in STO was {approx}1% as determined by transmission electron microscopy (TEM) and Rietveld refinements of x-ray diffraction (XRD) data. XRD analysis, performed in collaboration with NIST, on powder compositions on the STO/SrCuO{sub 2} tie line did not identify any ternary phases. SrCu{sub 0.10}Ti{sub 0.90}O{sub y} buffer layers were prepared by pulsed laser deposition (PLD) and CSD on IBAD MgO flexible metallic textured tapes. TEM analysis of a {approx}100 nm thick SrCu{sub 0.10}Ti{sub 0.90}O{sub y} buffer layer deposited by PLD showed a smooth Cu-doped STO/MgO interface. A {approx}600 nm thick YBCO film, deposited onto the SrCu{sub 0.10}Ti{sub 0.90}O{sub y} buffer by PLD, exhibited a T{sub c} of 87 K and critical current density (J{sub c}) of {approx}1 MA/cm{sup 2}. STO and Cu-doped STO thin films by CSD were {approx}30 nm thick. The in plane alignment (FWHM) after deposition of the STO improved by {approx}1{sup o} while it degraded by {approx}2{sup o} with the SrCu{sub 0.05}TiO{sub y} buffer. YBCO was deposited by PLD on the STO and SrCu{sub 0.05}TiO{sub y} buffers. The in plane alignment (FWHM) of the YBCO with the STO buffer layer slightly improved while that of the

  6. Inactivation and potential reactivation of pathogenic Escherichia coli O157:H7 in apple juice following ultraviolet light exposure at three monochromatic wavelengths.

    Science.gov (United States)

    Yin, Fugui; Zhu, Yan; Koutchma, Tatiana; Gong, Joshua

    2015-04-01

    Ultraviolet (UV) light irradiation at 254 nm is considered as a novel non-thermal method for decontamination of foodborne pathogenic bacteria. However, lower penetration depth of UV light at 254 nm in apple juice resulted in higher UV dose consumption during apple juice decontamination. In addition, no studies are available on the reactivation of pathogens following exposure to UV light in drinks and beverages. Two novel monochromatic UV light sources (λ = 222 and 282 nm) have been developed for bacterial disinfection. However, the inactivation of pathogenic Escherichia coli O157:H7 following exposure to these UV wavelengths is still unclear. Therefore, the present study was conducted to determine the inactivation and reactivation potential of pathogenic E. coli O157:H7 in apple juice following exposure to UV light at three monochromatic wavelengths: Far UV (λ = 222 nm), Far UV+ (λ = 282 nm) and UVC light (λ = 254 nm). The results showed that E. coli O157:H7 is acid-resistant, and up to 99.50% of cells survived in apple juice when incubated at 20 °C for 24 h. Inactivation of E. coli O157:H7 following exposure to Far UV light (2.81 Log reduction) was higher (P exposure to UV light as determined by the regular plating method. In addition, the exposure to Far UV light at 222 nm followed by incubating at 37 °C significantly decreased (P < 0.05) the survival of E. coli O157:H7 during dark incubation phase compared to that of UVC and Far UV+ light.

  7. A method for determination of {sup 90}Sr in vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Nygren, U

    1998-12-01

    This report describes a method for determination of {sup 90}Sr in vegetation. The method consists of wet-ashing the samples and separating Sr from the sample matrix by oxalate precipitation and extraction chromatography. {sup 90}Y ingrowth is awaited after which Y is separated from Sr and {sup 90}Y measured in a proportional counter. The method has been applied on two reference materials and the {sup 90}Sr results agree well with the recommended values. The method has also been used on 20 samples of blueberry twigs and the mean recovery of Sr was 74%

  8. ALICE Injected Beam Accidents

    CERN Document Server

    Appleby, R B

    2009-01-01

    The ALICE (point 2) interaction region is sensitive to beam orbit errors arising from magnet setting errors on injection. In this report, beam accident scenarios under injection for ALICE are described, focusing on ultra- fast error injection scenarios for the interaction straight correctors and dipoles. Beam 1 and beam 2 accident scenarios are considered, where the errors can lead to beam orbits striking the ALICE vacuum chamber or elements of the machine. The required thresholds for magnet current interlocks are calculated to avoid machine and detector risk.

  9. LHCb Injected Beam Accidents

    CERN Document Server

    Appleby, R B

    2009-01-01

    The LHCb (point 8) interaction region is sensitive to beam orbit errors arising from magnet setting errors on injection. In this report, beam accident scenarios under injection for LHCb are described, focusing on ultra- fast error injection scenarios for the interaction straight correctors and dipoles. Beam 1 and beam 2 accident scenarios are considered, where the errors can lead to beam orbits striking the LHCb vacuum chamber or elements of the machine. The required thresholds for magnet current interlocks are calculated to avoid machine and detector risk.

  10. Clathrate formation in the systems Sr-Cu-Ge and {Ba,Sr}-Cu-Ge

    Science.gov (United States)

    Zeiringer, I.; Moser, R.; Kneidinger, F.; Podloucky, R.; Royanian, E.; Grytsiv, A.; Bauer, E.; Giester, G.; Falmbigl, M.; Rogl, P.

    2014-09-01

    In the ternary system Sr-Cu-Ge, a novel clathrate type-I phase was detected, Sr8CuxGe46-x (5.2≤xtemperature interval. Sr8Cu5.3Ge40.7 decomposes eutectoidally on cooling at 730±3 °C into (Ge), SrGe2 and τ1-SrCu2-xGe2+x. Phase equilibria at 700 °C have been established for the Ge rich part and are characterized by the appearance of only one ternary compound, τ1-SrCu2-xGe2+x, which crystallizes with the ThCr2Si2 structure type and forms a homogeneity range up to x=0.4 (a=0.42850(4), c=1.0370(1) nm). Additionally, the extent of the clathrate type-I solid solution Ba8-ySryCuxGe46-x (0≤y≤~5.6; 5.2≤x≤5.4, from as cast alloys) has been studied at various temperatures. The clathrate type-I crystal structure (space group Pm3barn) has been proven by X-ray single crystal diffraction on two single crystals with the composition (from refinement): Sr8Cu5.36Ge40.64 (a=1.06368(2) nm at 300 K) and Ba4.86Sr3.14Cu5.36Ge40.64 (a=1.06748(2) nm at 300 K) measured at 300, 200 and 100 K. From the temperature dependence of the lattice parameters and the atomic displacement parameters, thermal expansion coefficients, Debye- and Einstein-temperatures and the speed of sound have been determined. From heat capacity measurements of Sr8Cu5.3Ge40.7 at low temperatures the Sommerfeld coefficient (γ=24 mJ/mol K2) and the Debye temperature (ΘDLT=273 K) have been extracted. From a detailed analysis of these data at higher temperatures, Einstein branches of the phonon dispersion relation have been derived and compared to those obtained from the atomic displacement parameters. Electrical resistivity measurements of Sr8Cu5.3Ge40.7 reveal a rather metallic behavior in the low temperature range (<300 K). Density function theory calculations provide densities of states, electronic resistivity and Seebeck coefficient as well as the vibrational spectrum and specific heat.

  11. Design considerations for a compact proton beam writing system aiming for fast sub-10 nm direct write lithography

    Science.gov (United States)

    Xu, Xinxin; Liu, Nannan; Raman, P. Santhana; Qureshi, Sarfraz; Pang, Rudy; Khursheed, Anjam; van Kan, Jeroen A.

    2017-08-01

    In order to realize sub-10 nm feature size by proton beam writing (PBW) with writing speed comparable to electron beam lithography (EBL), a 200 kV compact PBW system is proposed here. In this system, a new nano-aperture electron impact ion source with a potential reduced brightness of 106 A/(m2 srV) will be employed. To achieve sub-10 nm spot sizes with pA beam current, two different focusing lens configurations were evaluated. Both of these configurations were found to be theoretically capable of achieving sub-10 nm beam spot size.

  12. High-Spin States and Level Structure in Stable Nucleus 84Sr

    CERN Document Server

    Shen, Shuifa; Han, Guangbing; Wen, Shuxian; Yan, Yupeng; Yan, Shiwei; Wu, Xiaoguang; Zhu, Lihua; Li, Guangsheng; He, Chuangye

    2011-01-01

    High-spin states of 84Sr were populated through the reaction 70Zn(18O, 4n)84Sr at 75 MeV beam energy. Measurement of excitation function, gamma-gamma coincidences, directional correlation of oriented states (DCO) ratios and gamma-transition intensities were performed using eight anticompton HPGe detectors and one planar HPGe detector. Based on the measured results, a new level scheme of 84Sr was established in which 12 new states and nearly 30 new gamma-transitions were identified in the present work. The positive-parity states of the new level scheme were compared with results from calculations in the framework of the projected shell model (PSM). One negative-parity band was extended to spin I=19 and it can be found that in the high-spin states the gamma-transition energies show the nature of signature staggering. The negative-parity band levels are in good agreement with the deformed configuration-mixing shell model (DCM) calculations.

  13. The influence of Sr content in calcium phosphate coatings

    Energy Technology Data Exchange (ETDEWEB)

    Lindahl, Carl [Department of Biomaterials, Institute for Clinical Sciences, Sahlgrenska Academy at the University of Gothenburg, Gothenburg (Sweden); BIOMATCELL, VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg (Sweden); Pujari-Palmer, Shiuli; Hoess, Andreas; Ott, Marjam [Applied Materials Science, Department of Engineering Sciences, Uppsala University, Uppsala (Sweden); Engqvist, Håkan [BIOMATCELL, VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg (Sweden); Applied Materials Science, Department of Engineering Sciences, Uppsala University, Uppsala (Sweden); Xia, Wei, E-mail: wei.xia@angstrom.uu.se [BIOMATCELL, VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg (Sweden); Applied Materials Science, Department of Engineering Sciences, Uppsala University, Uppsala (Sweden)

    2015-08-01

    In this study calcium phosphate coatings with different amounts of strontium (Sr) were prepared using a biomineralization method. The incorporation of Sr changed the composition and morphology of coatings from plate-like to sphere-like morphology. Dissolution testing indicated that the solubility of the coatings increased with increased Sr concentration. Evaluation of extracts (with Sr concentrations ranging from 0 to 2.37 μg/mL) from the HA, 0.06Sr, 0.6Sr, and 1.2Sr coatings during in vitro cell cultures showed that Sr incorporation into coatings significantly enhanced the ALP activity in comparison to cells treated with control and HA eluted media. These findings show that calcium phosphate coatings could promote osteogenic differentiation even in a low amount of strontium. - Highlights: • Calcium phosphate coating doping with low Sr contents was prepared via a biomineralization process. • The solubility of the coatings increased with increased Sr concentration. • Present findings show the potential that Sr has on promoting osteogenic differentiation even in a low amount.

  14. Sr - an element shows the way - Applications of Sr isotopes for provenance, tracing and migration (Invited)

    Science.gov (United States)

    Prohaska, T.; Irrgeher, J.; Zitek, A.; Teschler Nicola, M.

    2010-12-01

    Strontium - named after the small Scottish town Strontian - as such is an element with little popularity. Firstly described by Martin Heinrich Klaproth in 1798, the metal is used in metallurgy to some extent whereas its compounds are interesting in glass industries, electronics and pyrotechnics. The element has chemical similarity to Ca and makes up 1/60 of the earth’s amount of the latter. Nonetheless, it is its isotopic composition which makes Sr so interesting for a large number of scientists. The natural composition of the four naturally occurring isotopes (84Sr, 86Sr 87Sr and 88Sr) varies in nature due to the radioactive decay of 87Rb to 87Sr. Thus, it was early recognized as geochronometer especially in Ca rich matrices. With increasing precision of applied methodology, the natural variation of the 87Sr/86Sr isotope ratio (analyzed at first mainly by thermal ionization mass spectrometry (TIMS)) became more and more popular in provenance studies. The natural variation of the ratio is mainly determined by the geological age and the original composition of the rock and can be used therefore as fingerprint of the local geology. The ratio is transferred with no significant fractionation via the water into plants and finally via the food chain into animal and human tissues (especially bones and teeth). As the element is chemically similar to Ca, it appears in most matrices. The use for provenance studies is supported by the fact that the long half life (4.8 x 1010 years) does not lead to an alteration during the time scales which are investigated (from recent samples to human or animal skeletal remains which date back up to 30.000 BC). The uniqueness of the system besides the natural variation is defined by the ubiquity in nature and the relatively high (and thus measurable) elemental concentration in most tissues. It was finally the advent of multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) which augmented the number of applications

  15. Refractive beam shapers for focused laser beams

    Science.gov (United States)

    Laskin, Alexander; Laskin, Vadim; Ostrun, Aleksei

    2016-09-01

    Focusing of laser radiation is most often used approach in various industrial micromachining applications like scribing, PCB drilling, and is important in scientific researches like laser heating in geophysics experiments with diamond anvil cells (DAC). Control of intensity distribution in focal spot is important task since optimum intensity profiles are rather flat-top, doughnut or "inverse-Gauss" than typical for lasers Gaussian profile. Because of high intensity of modern CW and pulsed lasers it is advisable to use refractive beam shaping optics with smooth optical surfaces providing high radiation resistance. Workable optical solutions can be built on the base of diffraction theory conclusion that flat-top intensity profile in focal plane of a lens is created when input beam has Airy-disk intensity distribution. It is suggested to apply refractive beam shapers converting, with minimum wavefront deformation, Gaussian profile of TEM00 beam to a beam with Airy disk intensity distribution, thereby optimizing conditions of interference near the focal plane of a lens after the beam shaper and providing flat-top, doughnut, "inverse-Gauss" profiles. This approach allows operation with CW and ultra-short pulse lasers, using F-theta lenses and objectives, mirror scanners, provides extended depth of field similar to Rayleigh length of comparable TEM00 beam, easy integration in industrial equipment, simple adjustment procedure and switching between profiles, telescope and collimator implementations. There will be considered design basics of beam shapers, analysis of profile behaviour near focal plane, examples of implementations in micromachining systems and experimental DAC setups, results of profile measurements and material processing.

  16. Free enthalpy landscape of SrO.

    Science.gov (United States)

    Schön, J C; Cancarević, Z P; Hannemann, A; Jansen, M

    2008-05-21

    Trying to predict thermodynamically stable and metastable solid compounds as function of pressure and temperature requires the global exploration of the enthalpy landscapes of chemical systems and the subsequent construction of their free enthalpy landscapes. In this work, we present a general approach to the determination of a free energy landscape. As an example, we construct the free enthalpy landscape of SrO for two different pressures on the empirical potential level and also compute various thermodynamic and elastic properties of SrO in the NaCl-, CsCl-, NiAs-, NbS-, TiP-, beta-BeO, sphalerite-, and wurtzite-structure type on an ab initio level. We employ density functional theory within the hybrid B3LYP approximation. The results show good agreement with experimental and theoretical data.

  17. Defects, stoichiometry, and electronic transport in SrTiO3-δ epilayers: A high pressure oxygen sputter deposition study

    Science.gov (United States)

    Ambwani, P.; Xu, P.; Haugstad, G.; Jeong, J. S.; Deng, R.; Mkhoyan, K. A.; Jalan, B.; Leighton, C.

    2016-08-01

    SrTiO3 is not only of enduring interest due to its unique dielectric, structural, and lattice dynamical properties, but is also the archetypal perovskite oxide semiconductor and a foundational material in oxide heterostructures and electronics. This has naturally focused attention on growth, stoichiometry, and defects in SrTiO3, one exciting recent development being such precisely stoichiometric defect-managed thin films that electron mobilities have finally exceeded bulk crystals. This has been achieved only by molecular beam epitaxy, however (and to a somewhat lesser extent pulsed laser deposition (PLD)), and numerous open questions remain. Here, we present a study of the stoichiometry, defects, and structure in SrTiO3 synthesized by a different method, high pressure oxygen sputtering, relating the results to electronic transport. We find that this form of sputter deposition is also capable of homoepitaxy of precisely stoichiometric SrTiO3, but only provided that substrate and target preparation, temperature, pressure, and deposition rate are carefully controlled. Even under these conditions, oxygen-vacancy-doped heteroepitaxial SrTiO3 films are found to have carrier density, mobility, and conductivity significantly lower than bulk. While surface depletion plays a role, it is argued from particle-induced X-ray emission (PIXE) measurements of trace impurities in commercial sputtering targets that this is also due to deep acceptors such as Fe at 100's of parts-per-million levels. Comparisons of PIXE from SrTiO3 crystals and polycrystalline targets are shown to be of general interest, with clear implications for sputter and PLD deposition of this important material.

  18. In situ Sr/Sr investigation of igneous apatites and carbonates using laser-ablation MC-ICP-MS

    DEFF Research Database (Denmark)

    Bizzarro, Martin; Simonetti, A.; Stevenson, R.K.;

    2003-01-01

    In situ Sr isotopic compositions of coexisting apatite and carbonate for carbonatites from the Sarfartoq alkaline complex, Greenland, have been determined by laser-ablation multicollector inductively coupled plasma mass spectrometry. This study is the first to examine the extent of Sr isotopic...... spectrometry but in a much shorter interval of time (100 s vs.>1 h, respectively). The combined total analyses (n = 107) of apatite and carbonate yield Sr/Sr compositions ranging from ~ 0.7025 to ~ 0.7031. This relatively large variation in Sr isotopic compositions (~ 0.0006) is ~ 1 order of magnitude larger...... than the estimated external reproducibility (~ 0.00005,2s) of the method. The large range in Sr/Sr values suggests that apatite and carbonate precipitated predominantly under nonequilibrium conditions. The isotopic variations observed within individual hand specimens may therefore reflect larger...

  19. Implicazioni cliniche ed economiche di tramadolo SR

    Directory of Open Access Journals (Sweden)

    Lorenzo Pradelli

    2004-12-01

    Full Text Available Tramadol is one of the preferred weak opioid agonists in the management of chronic pain, due to a good efficacy and safety profile, to a particularly low interference with cardiovascular and respiratory functions and a low dependence and abuse potential. The successful use of tramadol, nevertheless, is often limited by low patient compliance, a consequence of gastrointestinal side effects (mainly nausea and vomiting and frequent dosing regimens, among other reasons. In this paper, clinical studies conducted on slow-release formulations of tramadol and other strategies for compliance improvement in various pain conditions are reviewed. From the examined literature, it appears that the strategy with the best compliance is the use of slow release (SR formulations, which simplify dosing regimens and tend to have a somewhat better tolerability, and a slow dose escalation, which improves tolerability. The advantages of SR formulations have to be weighed against the superior acquisition cost and the slower onset of analgesia. A frame for the evaluation of the clinical and economical advantages and disadvantages of SR versus immediate release formulations of tramadol is also proposed.

  20. Induction of CaSR expression circumvents the molecular features of malignant CaSR null colon cancer cells.

    Science.gov (United States)

    Singh, Navneet; Chakrabarty, Subhas

    2013-11-15

    We recently reported on the isolation and characterization of calcium sensing receptor (CaSR) null human colon cancer cells (Singh et al., Int J Cancer 2013; 132: 1996-2005). CaSR null cells possess a myriad of molecular features that are linked to a highly malignant and drug resistant phenotype of colon cancer. The CaSR null phenotype can be maintained in defined human embryonic stem cell culture medium. We now show that the CaSR null cells can be induced to differentiate in conventional culture medium, regained the expression of CaSR with a concurrent reversal of the cellular and molecular features associated with the null phenotype. These features include cellular morphology, expression of colon cancer stem cell markers, expression of survivin and thymidylate synthase and sensitivity to fluorouracil. Other features include the expression of epithelial mesenchymal transition linked molecules and transcription factors, oncogenic miRNAs and tumor suppressive molecule and miRNA. With the exception of cancer stem cell markers, the reversal of molecular features, upon the induction of CaSR expression, is directly linked to the expression and function of CaSR because blocking CaSR induction by shRNA circumvented such reversal. We further report that methylation and demethylation of the CaSR gene promoter underlie CaSR expression. Due to the malignant nature of the CaSR null cells, inclusion of the CaSR null phenotype in disease management may improve on the mortality of this disease. Because CaSR is a robust promoter of differentiation and mediates its action through diverse mechanisms and pathways, inactivation of CaSR may serve as a new paradigm in colon carcinogenesis.

  1. Stoichiometry as key to ferroelectricity in compressively strained SrTiO{sub 3} films

    Energy Technology Data Exchange (ETDEWEB)

    Haislmaier, R. C.; Engel-Herbert, R.; Gopalan, V. [Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2016-07-18

    While strain is a powerful tuning parameter for inducing ferroelectricity in thin film oxides, the role of stoichiometry control is critical, but far less explored. A series of compressively strained SrTiO{sub 3} films on (001) (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.35} substrates were grown by hybrid molecular beam epitaxy where the Ti cation was supplied using a metal-organic titanium tetraisopropoxide molecule that helps systematically and precisely control Sr:Ti stoichiometry in the resulting films. A stoichiometric growth window is located through X-ray diffraction and in-situ reflection high-energy electron diffraction measurements, which show a minimum out-of-plane lattice parameter as well as constant growth rate within the stoichiometric growth window range. Using temperature dependent optical second harmonic generation (SHG) characterization, a ferroelectric-to-paraelectric transition at T ∼ 180 K is observed for a stoichiometric SrTiO{sub 3} film, as well as a higher temperature structural transition at T ∼ 385 K. Using SHG polarimetry modeling, the polar point group symmetry is determined to be tetragonal 4mm with the polarization pointing out-of-plane of the film. The SHG coefficients, d{sub 31}/d{sub 15}=3 and d{sub 33}/d{sub 15}=21, were determined at 298 K. The ferroelectric transition disappears in films grown outside the growth window, thus proving the critical role of stoichiometry control in realizing strain-induced ferroelectricity.

  2. Improving the quality of proton beams via double targets driven by an intense circularly polarized laser pulse

    Directory of Open Access Journals (Sweden)

    Yanxia Xu

    2016-10-01

    Full Text Available A new scheme is proposed to improve the quality of proton beams via ultra-intense laser pulse interacting with double plasma targets, which consist of a pre-target with relatively low density and a main target with high density. Both one- and two-dimensional Particle-in-Cell simulations show that, the using of an appropriate pre-target can help to obtain a much stronger longitudinal charge separation field in contrast to using only the main target. And proton beam with lower momentum divergence, better monochromaticity and collimation, as well as higher current density is generated. Moreover, due to the strengthened coupling between the laser pulse and targets, the energy conversion from laser pulse to protons is also increased.

  3. Electronic parameters of Sr2M2O7 (M = V, Nb, Ta) and Sr-O chemical bonding

    DEFF Research Database (Denmark)

    Atuchin, Victor V.; Grivel, Jean-Claude; Zhang, Zhaoming

    2010-01-01

    on the formation of the Sr-O bonds. The chemical bonding effects were considered on the basis of our XPS results for Sr2Nb2O7 and Sr2Ta2O7 and the previously published structural and XPS data for other Sr-oxide compounds. A new empirical relationship between Δ(O-Sr) and L(Sr-O) was obtained. Possible applications...

  4. Laser Beam Focus Analyser

    DEFF Research Database (Denmark)

    Nielsen, Peter Carøe; Hansen, Hans Nørgaard; Olsen, Flemming Ove

    2007-01-01

    The quantitative and qualitative description of laser beam characteristics is important for process implementation and optimisation. In particular, a need for quantitative characterisation of beam diameter was identified when using fibre lasers for micro manufacturing. Here the beam diameter limits...... the obtainable features in direct laser machining as well as heat affected zones in welding processes. This paper describes the development of a measuring unit capable of analysing beam shape and diameter of lasers to be used in manufacturing processes. The analyser is based on the principle of a rotating...... mechanical wire being swept through the laser beam at varying Z-heights. The reflected signal is analysed and the resulting beam profile determined. The development comprised the design of a flexible fixture capable of providing both rotation and Z-axis movement, control software including data capture...

  5. KEKB beam instrumentation systems

    Science.gov (United States)

    Arinaga, M.; Flanagan, J.; Hiramatsu, S.; Ieiri, T.; Ikeda, H.; Ishii, H.; Kikutani, E.; Mimashi, T.; Mitsuhashi, T.; Mizuno, H.; Mori, K.; Tejima, M.; Tobiyama, M.

    2003-02-01

    For the stable high-luminosity operation and luminosity increase, the electron and positron storage rings of the KEK B-Factory (KEKB) is equipped with various beam instrumentations, which have been working well since the start of the commissioning in December, 1998. Details and performance of the beam-position monitor system based on the spectrum analysis using DSPs, the turn-by-turn BPM with four-dimensional function available for measurements of the individual bunch position, phase and intensity, the parametric beam-DCCTs designed so as to avoid the magnetic-core-selection problems for the parametric flux modulation, the bunch-by-bunch feedback system indispensable to suppress the strong multibunch instabilities in KEKB, the various optical beam diagnostic systems, such as synchrotron radiation interferometers for precise beam-size measurement, the tune meters, the bunch length monitors and the beam-loss monitors are described. Delicate machine tuning of KEKB is strongly supported by these instrumentations.

  6. The evolution of oceanic 87Sr/86Sr does not rule out early continental growth

    Science.gov (United States)

    Flament, N.; Coltice, N.; Rey, P. F.

    2010-12-01

    Many contrasted continental growth models have been proposed to date, in which the amount of continental material extracted from the mantle at 3.8 Ga ranges between 0% (e.g. Taylor and McLennan, 1985) and 100% (e.g. Armstrong, 1981). One of the arguments in favor of delayed continental growth models is the shift in the 87Sr/86Sr of marine carbonates from mantle composition at ~ 2.8 Ga (Shields and Veizer, 2002). When using oceanic 87Sr/86Sr as a proxy of continental growth, the flux of strontium from the continents to the oceans is assumed to depend only on continental area and both continental hypsometry and continental freeboard are assumed to be constant through time. However, Rey and Coltice (2008) suggested that Archean reliefs were lower than present-day ones and Flament et al. (2008) suggested that the emerged land area is not proportional to continental growth. Therefore, the suitability of 87Sr/86Sr as a proxy of continental growth must be re-assessed. In this contribution, we develop an integrated model, from the mantle to the surface, to investigate the effect of contrasted continental growth models on the evolution of sea level, of the area of emerged land, and of oceanic 87Sr/86Sr. We estimate the evolution of mantle temperature using the model of Labrosse and Jaupart (2007) that takes the effect of continental growth into account. The maximum continental elevation is calculated using the results of Rey and Coltice (2008), sea level and the area of emerged land are calculated as in Flament et al. (2008), and the oceanic 87Sr/86Sr is calculated in a geochemical box model. We calculate Archean sea levels ~ 800 m higher than present for delayed continental growth and ~ 1500 m higher for early continental growth. In contrast, we calculate similar Archean areas of emerged land, of less than 5% of the Earth’s surface, for both early and delayed continental growth models. Because the area of emerged land does not depend on continental growth models, the

  7. Characterization of domain structure in one-dimensional SrRuO{sub 3} nanostructure using synchrotron x-ray microdiffraction

    Energy Technology Data Exchange (ETDEWEB)

    Imai, Yasuhiko, E-mail: imai@spring8.or.jp [Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), Sayo, Hyogo 679-5198 Japan (Japan); Kimura, Shigeru [Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), Sayo, Hyogo 679-5198 Japan (Japan); Japan Science and Technology Agency, CREST, Uji, Kyoto 611-0011 (Japan); Kan, Daisuke; Shimakawa, Yuichi [Japan Science and Technology Agency, CREST, Uji, Kyoto 611-0011 (Japan); Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2016-07-27

    SrRuO{sub 3} (SRO) thin films with a geometric shape of one-dimensional stripes can be epitaxially grown on a SrTiO{sub 3} (STO) substrate. Conventional X-ray reciprocal space map (RSM) measurements revealed that the stripes consist of multiple crystallographic domains. We performed synchrotron X-ray microdiffraction measurements to determine whether the single stripe of the SRO has a single crystallographic domain or not. Spacing between stripes is ~200 nm that is comparable to a beam size available for the microdiffraction. The synchrotron X-ray microdiffraction experiment was performed at BL13XU, SPring-8. RSMs of asymmetric diffractions around STO 204 reflection were measured by a broad-beam (200 × 200 µm{sup 2}) and the sub-micro-beam (250(h) × 190(v) nm{sup 2}). Both SRO 260 and 620 are seen in the RSM measured by the broad-beam due to the crystallographic twinning. On the other hand, only SRO 620 is observed in the RSM measured by the sub-micro-beam. The result shows the domain length of the single stripe SRO thin film is longer than the vertical beam size of 190 nm.

  8. The Physics and Applications of High Brightness Electron Beams

    Science.gov (United States)

    Palumbo, Luigi; Rosenzweig, J.; Serafini, Luca

    2007-09-01

    Plenary sessions. RF deflector based sub-Ps beam diagnostics: application to FEL and advanced accelerators / D. Alesini. Production of fermtosecond pulses and micron beam spots for high brightness electron beam applications / S.G. Anderson ... [et al.]. Wakefields of sub-picosecond electron bunches / K.L.F. Bane. Diamond secondary emitter / I. Ben-Zvi ... [et al.]. Parametric optimization for an X-ray free electron laser with a laser wiggler / R. Bonifacio, N. Piovella and M.M. Cola. Needle cathodes for high-brightness beams / C.H. Boulware ... [et al.]. Non linear evolution of short pulses in FEL cascaded undulators and the FEL harmonic cascade / L. Giannessi and P. Musumeci. High brightness laser induced multi-meV electron/proton sources / D. Giulietti ... [et al.]. Emittance limitation of a conditioned beam in a strong focusing FEL undulator / Z. Huang, G. Stupakov and S. Reiche. Scaled models: space-charge dominated electron storage rings / R.A. Kishek ... [et al.]. High brightness beam applications: energy recovered linacs / G.A. Krafft. Maximizing brightness in photoinjectors / C. Limborg-Deprey and H. Tomizawa. Ultracold electron sources / O.J. Luiten ... [et al.]. Scaling laws of structure-based optical accelerators / A. Mizrahi, V. Karagodsky and L. Schächter. High brightness beams-applications to free-electron lasers / S. Reiche. Conception of photo-injectors for the CTF3 experiment / R. Roux. Superconducting RF photoinjectors: an overview / J. Sekutowicz. Status and perspectives of photo injector developments for high brightness beams / F. Stephan. Results from the UCLA/FNLP underdense plasma lens experiment / M.C. Thompson ... [et al.]. Medical application of multi-beam compton scattering monochromatic tunable hard X-ray source / M. Uesaka ... [et al.]. Design of a 2 kA, 30 fs RF-photoinjector for waterbag compression / S.B. Van Der Geer, O.J. Luiten and M.J. De Loos. Proposal for a high-brightness pulsed electron source / M. Zolotorev ... [et al

  9. Thin Film, Near-Surface and Multi-Layer Investigations by Low-Energy {mu}{sup +}SR

    Energy Technology Data Exchange (ETDEWEB)

    Prokscha, T., E-mail: thomas.prokscha@psi.ch; Morenzoni, E.; Suter, A.; Khasanov, R.; Luetkens, H.; Eshchenko, D.; Garifianov, N. [Paul Scherrer Institute, PSI (Switzerland); Forgan, E. M. [University of Birmingham (United Kingdom); Keller, H. [Universitaet Zuerich (Switzerland); Litterst, J. [Technische Universitaet Braunschweig (Germany); Niedermayer, C. [Paul Scherrer Institute, PSI (Switzerland); Nieuwenhuys, G. [Leiden University (Netherlands)

    2004-12-15

    At the Paul Scherrer Institute (PSI, Villigen, Switzerland) the beam of low-energy positive polarised muons (LE-{mu}{sup +}) with tunable energy between 0.5 and 30 keV allows the extension of the muon-spin-rotation technique ({mu}SR) to studies on thin films and multi-layers (LE-{mu}{sup +}SR). The range of these muons in solids covers the near-surface region up to implantation depths of about 300 nm. As a sensitive local magnetic probe with a complementary observational time window to other techniques LE-{mu}{sup +}SR offers the unique possibility to gain new insights in these nano-scale objects. After outlining the current status of the LE-{mu}{sup +} beam line we demonstrate the potential of this new technique by presenting the results of recent experiments: i) the direct observation of non-local effects in a superconducting Pb film, ii) the oxygen isotope effect on the in-plane penetration depth in optimally doped YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}, and iii) the first observation of the conduction electron spin polarisation in the Ag spacer of a Fe/Ag/Fe tri-layer.

  10. Resolving Two Beams in Beam Splitters with a Beam Position Monitor

    Science.gov (United States)

    Kurennoy, Sergey

    2002-04-01

    The beam transport system for the Advanced Hydrotest Facility (AHF) anticipates multiple beam splitters. Monitoring two transversely separated beams in a common beam pipe in the splitter sections imposes certain requirements on beam diagnostics for these sections. We explore a two-beam system in a generic beam monitor and study the feasibility of resolving the transverse positions of the two beams with one diagnostics device. Effects of unequal beam currents and of finite transverse sizes of the beams are explored analytically for both the ultra relativistic case and the long-wavelength limit.

  11. Chilled beam application guidebook

    CERN Document Server

    Butler, David; Gräslund, Jonas; Hogeling, Jaap; Lund Kristiansen, Erik; Reinikanen, Mika; Svensson, Gunnar

    2007-01-01

    Chilled beam systems are primarily used for cooling and ventilation in spaces, which appreciate good indoor environmental quality and individual space control. Active chilled beams are connected to the ventilation ductwork, high temperature cold water, and when desired, low temperature hot water system. Primary air supply induces room air to be recirculated through the heat exchanger of the chilled beam. In order to cool or heat the room either cold or warm water is cycled through the heat exchanger.

  12. Hyperon beam physics

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, P.S.

    1996-03-01

    This report reviews the present status and recent results in hyperon physics concentrating on results from high energy hyperon beam experiments performed at Fermilab over the past several years. The report focuses on hyperon production polarization, precision hyperon magnetic moment measurements and radiative decay studies. Modern charged hyperon beam experiments are characterized by {approx}100m long apparatus and hyperon beams with {gamma}{sub Y}{approx}100 and hyperon fluxes in the 1-100 kHz range.

  13. The MECO muon beam

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, M. [Department of Physics and Astronomy, University of California at Irvine, Irvine, California 92697--4575 (United States)

    1998-08-01

    The muon beam required by MECO, a muon conversion experiment, has been studied and simulated using GEANT3. The beam selects low energy, negative muons sufficient to perform a measurement of muon conversion to a level of 10{sup {minus}16} by relying on a graded magnetic solenoidal field and a curved transport solenoid equipped with collimators. Some details of the beam and simulation are discussed. {copyright} {ital 1998 American Institute of Physics.}

  14. Mechanically reinforced glass beams

    DEFF Research Database (Denmark)

    Nielsen, Jens Henrik; Olesen, John Forbes

    2007-01-01

    to breakage without any warning or ductility, which can be catastrophic if no precautions are taken. One aspect of this issue is treated here by looking at the possibility of mechanically reinforcing glass beams in order to obtain ductile failure for such a structural component. A mechanically reinforced...... the mechanical behavior of the beam is explained. Finally, some design criterions for reinforced glass beams are discussed....

  15. High-speed tomography using pink beam at GeoSoilEnviroCARS

    Science.gov (United States)

    Rivers, Mark L.

    2016-10-01

    Synchrotron microtomography typically uses monochromatic beams, because these avoid beam-hardening artifacts and allow imaging above and below the absorption edges of specific elements. However, the monochromator greatly reduces the flux on the sample, and thus increases the data collection time. An alternative is to eliminate the monochromator, instead using absorbers to remove low-energy x-rays and reflection from a mirror to remove high-energy x-rays. This produces a pink beam with a large energy bandwidth and more than 1000 times greater flux. This is useful for dynamic studies, where an entire 3-D dataset can be collected in just a few seconds. We have implemented pink beam tomography at the 13-BM-D beamline at the GeoSoilEnviroCARS sector 13 at the Advanced Photon Source. A key component of such a system is a high-speed detector that can collect over 100 frames/s with excellent signal/noise. We are using a new generation of inexpensive CMOS detectors with very low read noise, large full-well capacity, and high speed. The system performs well, and first experiments in studying fluid imbibition and drainage are presented.

  16. Gate voltage control of the AlO x /SrTiO3 interface electrical properties

    Science.gov (United States)

    Delahaye, J.; Grenet, T.

    2016-10-01

    Electron-beam deposition of an insulating granular aluminium or off-stoichiometric amorphous alumina layer on a SrTiO3 surface is a simple way to get a metallic interface from insulating materials. No heating nor specific preparation of the SrTiO3 surface is needed. In this paper, we investigate how the electrical properties of this interface can be tuned by the use of a back gate voltage (electrical field through the SrTiO3 substrate). We demonstrate that the slow field-effect observed at room temperature can be used to tune in a controlled, reversible way the low temperature electrical properties of the interface. In particular, important parameters of a transistor such as the amplitude of the resistance response to gate voltage changes or the existence of an ‘on’ or an ‘off’ state at zero gate voltage and at low temperature can be adjusted in a single sample. This method should be applicable to any SrTiO3-based interface in which oxygen vacancies are involved and might provide a powerful way to study the metal or superconductor insulator transition observed in such systems.

  17. Search for half-flux-quantum Little-Parks oscillations in mesoscopic rings of Sr2RuO4

    Science.gov (United States)

    Cai, Xinxin; Zakrzewski, Brian; Ying, Yiqun; Fobes, David; Liu, Tijiang; Mao, Zhiqiang; Liu, Ying

    2015-03-01

    Recent cantilever magnetometry measurements on micron-sized, doubly-connected crystals of Sr2RuO4 have indicated that a half-flux-quantum state may be present in this material. To provide independent evidence for the presence of this new topological object by electrical transport measurements and examine its stability, we carried out Little-Parks (L-P) oscillation measurements, which trace out the phase boundary of a system, on mesoscopic rings of Sr2RuO4. Sr2RuO4 rings were fabricated using a combination of mechanical exfoliation of Sr2RuO4 single crystals, photolithography, and focused ion beam techniques. Without an in-plane magnetic field, large-amplitude resistance oscillations of a full-flux quantum were found as ramping the out-of-plane field. When the in-plane field and the measurement current were sufficiently large, a pronounced second set of resistance peaks was observed in one sample, supporting the existence of half-flux-quantum states. Preparation and measurements on more samples have been carried out and the most recent measurements suggest that the half-flux-quantum states, if indeed present, are likely to be metastable. This work is supported by DOE under Grant DE-FG02-04ER46159.

  18. Study of [beta][sup +] and electron capture decay of [sup 76]Sr in [gamma]-[gamma] coincidence measurements

    Energy Technology Data Exchange (ETDEWEB)

    Adzic, P.R.; Zupancic, M.T.; Vukanovic, R.B.; Anicin, I.V.; Skoro, G.P.; Kukoc, A.H. (Institute of Nuclear Sciences Vinca' ' , POB 522, 11001 Belgrade (Yugoslavia)); Lindroos, M.; Tengblad, O.; Veskovic, M.; ISOLDE Collaboration (CERN, PPE Division, CH-1211 Geneva 23 (Switzerland))

    1993-12-01

    The main goal of this work is to establish the nuclear decay scheme of [sup 76]Sr and energy levels of its doubly odd daughter nucleus [sup 76]Rb. The extremely neutron deficient nucleus [sup 76]Sr lying at the [ital N]=[ital Z] (=38) line with half-life of 8.9 s was produced in spallation reactions of 600 MeV protons from the CERN Synchrocyclotron (SC) with a Nb multifoil target in conjunction with a W surface ionization source at the ISOLDE facility. The [gamma]-spectroscopy measurements have been performed with two Ge detectors which were positioned at about [plus minus]30[degree] respectively downstream to the [sup 76]Sr beam. The obtained singles and coincidence [gamma] spectra were used to determine energies and intensities of [gamma] lines assigned to the decay of [sup 76]Sr and to establish some details of the nuclear level configuration of its daughter nucleus [sup 76]Rb up to 1000 keV.

  19. Beam Instrumentation and Diagnostics

    CERN Document Server

    Strehl, Peter

    2006-01-01

    This treatise covers all aspects of the design and the daily operations of a beam diagnostic system for a large particle accelerator. A very interdisciplinary field, it involves contributions from physicists, electrical and mechanical engineers and computer experts alike so as to satisfy the ever-increasing demands for beam parameter variability for a vast range of operation modi and particles. The author draws upon 40 years of research and work, most of them spent as the head of the beam diagnostics group at GSI. He has illustrated the more theoretical aspects with many real-life examples that will provide beam instrumentation designers with ideas and tools for their work.

  20. Beam cavity interaction

    CERN Document Server

    Gamp, A

    2011-01-01

    We begin by giving a description of the rf generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, rf feedback, and feed-forward are described. Examples of digital rf phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  1. Plasma Beam Measurements

    Science.gov (United States)

    1991-08-01

    GUN PLASMA BEAM / ,I 21 cm diameter = 0 GLASS DRIFT TUBE 50 cm diameter MCP CAMERA CLASS CROSSES (a) Gun muzzle /"- PLASA BEAM / TAROT z = 10 m MCP...discusses some of the hydrodynamic issues related to the calcula- tions. The reader may well wonder why hydrodynamics should be an issue in a 116 WL-TR-90...answer is yes for the slow beam cases and no for the fast beam cases. This is explained further. 118 WL-TR-90-83 The reader will recall the

  2. ALFA beam halo

    CERN Document Server

    Komarek, Tomas

    2014-01-01

    This note serves as a final report about CERN Summer Student Programme 2014 project. The beam halo is an undesired phenomenon for physics analyses on particle accelerators. It surrounds the beam core and constitutes an important part of background for signal measurements on some detectors, eg. in the forward region. In this study, the data from the ALFA detector were used, specifically from the run 191373 ($\\beta^*=90\\unit{m}$) and the run 213268 ($\\beta^*=1\\unit{km}$). Using the ROOT framework, a software for beam halo events selection was created and beam halo properties were examined. In the run 213268, excessive beam halo is suspected to be the reason for multiple beam scrapings that occurred. A kinematic reconstruction of beam halo particles is attempted in order to understand beam halo properties in the interaction point. Some further simulations are employed to find constraints for beam halo particles in order to survive in the accelerator for a longer time/many revolutions. This work represents a st...

  3. (Pulsed electron beam precharger)

    Energy Technology Data Exchange (ETDEWEB)

    Finney, W.C. (ed.); Shelton, W.N.

    1990-01-01

    This report discusses the following topics on electron beam guns: Precharger Modification; Installation of Charge vs. Radius Apparatus; High Concentration Aerosol Generation; and Data Acquisition and Analysis System.

  4. Simulation of Beam-Beam Background at CLIC

    CERN Document Server

    Sailer, A

    2010-01-01

    The dense beams used at CLIC to achieve a high luminosity will cause a large amount of background particles through beam-beam interactions. Generator level studies with GUINEAPIG and full detector simulation studies with an ILD based CLIC detector have been performed to evaluate the amount of beam-beam back- ground hitting the vertex detector.

  5. Theoretical modeling and experimental observations of the atomic layer deposition of SrO using a cyclopentadienyl Sr precursor

    Science.gov (United States)

    Fredrickson, Kurt D.; McDaniel, Martin D.; Slepko, Alex; Ekerdt, John G.; Demkov, Alexander A.

    2016-08-01

    First-principle calculations are used to model the adsorption and hydration of strontium bis(cyclopentadienyl) [Sr(Cp)2] on TiO2-terminated strontium titanate, SrTiO3 (STO), for the deposition of strontium oxide, SrO, by atomic layer deposition (ALD). The Sr(Cp)2 precursor is shown to adsorb on the TiO2-terminated surface, with the Sr atom assuming essentially the bulk position in STO. The C-Sr bonds are weaker than in the free molecule, with a Ti atom at the surface bonding to one of the C atoms in the cyclopentadienyl rings. The surface does not need to be hydrogenated for precursor adsorption. The calculations are compared with experimental observations for a related Sr cyclopentadienyl precursor, strontium bis(triisopropylcyclopentadienyl) [Sr(iPr3Cp)2], adsorbed on TiO2-terminated STO. High-resolution x-ray photoelectron spectroscopy and low-energy ion scattering spectroscopy show adsorption of the Sr precursor on the TiO2-terminated STO after a single precursor dose. This study suggests that ALD growth from the strontium precursors featuring cyclopentadienyl ligands, such as Sr(Cp)2, may initiate film growth on non-hydroxylated surfaces.

  6. Luminescent studies of impurity doped SrS phosphors

    Indian Academy of Sciences (India)

    Vijay Singh; Manoj Tiwari; T K Gundu Rao; S J Dhoble

    2005-02-01

    SrS phosphors activated with Ce and Dy ions were prepared by solid-state diffusion method. Photoluminescent study was carried out on SrS : Ce, SrS : Dy and SrS : Dy, Ce. Thermoluminescence and electron spin resonance studies were also carried out on SrS : Dy phosphor. The thermoluminescence glow curve shows a peak at around 142°C. Irradiated SrS : Dy exhibits an ESR line due to a defect centre. Thermal annealing behaviour indicates that this centre correlates with the TL peak at 142°C. The centre is characterized by an isotropic g-value of 2.0039 and is assigned to a + centre.

  7. Advances in the Study of SR Protein Family

    Institute of Scientific and Technical Information of China (English)

    XiaoyunMa; FuchuHe

    2003-01-01

    The name of SR proteins is derived from their typical RS domain that is rich in serine(Ser,S)and arginine(Arg,R).They are conserved in evolution.Up to now,10 members of the SR protein family have been identified in humans.SR proteins contain one or two RNA binding motifs aside from the RS domain,and also possess special biochemical and immunological features.As to the functions of SR proteins,they facilitate the recruitment of the components of splicesome via protein-protein interaction to prompt the assembly ofearly aplicesome;while in alternative splicing,tissue-specifically expressed SR protein along with the relative ratio of SR protein and heterogeneous nuclear ribonucleoprotein(hnRNP)is composed of two main regulative mechanisms for alternative splicing.Almost all of the biochemical functions are regulated by reversible phosphorylation.

  8. Advances in the Study of SR Protein Family

    Institute of Scientific and Technical Information of China (English)

    Xiaoyun Ma; Fuchu He

    2003-01-01

    The name of SR proteins is derived from their typical RS domain that is rich in serine (Ser, S) and arginine (Arg, R). They are conserved in evolution. Up to now, 10 members of the SR protein family have been identified in humans. SR proteins contain one or two RNA binding motifs aside from the RS domain, and also possess special biochemical and immunological features. As to the functions of SR proteins, they facilitate the recruitment of the components of splicesome via protein-protein interaction to prompt the assembly of early splicesome; while in alternative splicing, tissue-specifically expressed SR protein along with the relative ratio of SR protein and heterogeneous nuclear ribonucleoprotein (hnRNP) is composed of two main regulative mechanisms for alternative splicing. Almost all of the biochemical functions are regulated by reversible phosphorylation.

  9. Resolving Two Beams in Beam Splitters with a Beam Position Monitor

    CERN Document Server

    Kurennoy, S S

    2002-01-01

    The beam transport system for the Advanced Hydrotest Facility (AHF) anticipates multiple beam splitters [1]. Monitoring two separated beams in a common beam pipe in the splitter sections imposes certain requirements on diagnostics for these sections. In this note we explore a two-beam system in a generic beam monitor and study the feasibility of resolving the positions of the two beams with a single diagnostic device.

  10. Monochromatic excimer light (308 nm) for the treatment of skin diseases%308 nm准分子光治疗皮肤病进展

    Institute of Scientific and Technical Information of China (English)

    丛林; 杨蓉娅

    2015-01-01

    308 nm准分子光是一种单频中波紫外光,为治疗白癜风的首选疗法之一.308 nm准分子光和308 nm准分子激光治疗白癜风的疗效无明显差异.研究表明,308 nm准分子光还可作为银屑病、掌跖脓疱病、斑秃等慢性皮肤病新的治疗选择.目前已有308 nm准分子光治疗无色素痣、蕈样肉芽肿、CD30+淋巴瘤样丘疹病、硬化性苔癣、结节性痒疹、局限性硬皮病、环状肉芽肿及浆细胞唇炎的个案报道,与传统光疗相比,308 nm准分子光累积照射剂量少,发生皮肤癌的风险极低,其不良反应主要为暂时性红斑.308 nm准分子光的治疗机制尚不明确.%As a kind of monochromatic ultraviolet B,308-nm monochromatic excimer light (MEL) is one of the first choice treatments for vitiligo.There is no significant difference in the therapeutic effect on vitiligo between 308-nm MEL and 308-nm excimer laser.Recent studies have shown that 308-nm MEL can also serve as the treatment of choice for some other chronic skin diseases,such as psoriasis,palmoplantaris pustulosis and alopecia areata.Furthermore,there have been case reports on the use of 308-nm MEL for the treatment of achromic naevus,mycosis fungoides,CD30+ lymphomatoid papulosis,lichen sclerosus,prurigo nodularis,localized scleroderma,granuloma annulare and plasma cell cheilitis.Compared with conventional phototherapy,308-nm MEL has the advantages of less cumulative radiation dose and lower risks of skin cancers.The main adverse reaction to 308-nm MEL is transient erythema.The therapeutic mechanism of 308-nm MEL is still unclear.

  11. Incorporation of La in epitaxial SrTiO3 thin films grown by atomic layer deposition on SrTiO3-buffered Si (001) substrates

    Science.gov (United States)

    McDaniel, Martin D.; Posadas, Agham; Ngo, Thong Q.; Karako, Christine M.; Bruley, John; Frank, Martin M.; Narayanan, Vijay; Demkov, Alexander A.; Ekerdt, John G.

    2014-06-01

    Strontium titanate, SrTiO3 (STO), thin films incorporated with lanthanum are grown on Si (001) substrates at a thickness range of 5-25 nm. Atomic layer deposition (ALD) is used to grow the LaxSr1-xTiO3 (La:STO) films after buffering the Si (001) substrate with four-unit-cells of STO deposited by molecular beam epitaxy. The crystalline structure and orientation of the La:STO films are confirmed via reflection high-energy electron diffraction, X-ray diffraction, and cross-sectional transmission electron microscopy. The low temperature ALD growth (˜225 °C) and post-deposition annealing at 550 °C for 5 min maintains an abrupt interface between Si (001) and the crystalline oxide. Higher annealing temperatures (650 °C) show more complete La activation with film resistivities of ˜2.0 × 10-2 Ω cm for 20-nm-thick La:STO (x ˜ 0.15); however, the STO-Si interface is slightly degraded due to the increased annealing temperature. To demonstrate the selective incorporation of lanthanum by ALD, a layered heterostructure is grown with an undoped STO layer sandwiched between two conductive La:STO layers. Based on this work, an epitaxial oxide stack centered on La:STO and BaTiO3 integrated with Si is envisioned as a material candidate for a ferroelectric field-effect transistor.

  12. Structural characterization of niobium oxide thin films grown on SrTiO3 (111) and (La,Sr)(Al,Ta)O3 (111) substrates

    Science.gov (United States)

    Dhamdhere, Ajit R.; Hadamek, Tobias; Posadas, Agham B.; Demkov, Alexander A.; Smith, David J.

    2016-12-01

    Niobium oxide thin films have been grown by molecular beam epitaxy on SrTiO3 (STO) (111) and (La0.18Sr0.82)(Al0.59Ta0.41)O3 (LSAT) (111) substrates. Transmission electron microscopy (TEM) confirmed the formation of high quality films with coherent interfaces. Films grown with higher oxygen pressure on STO (111) resulted in a (110)-oriented NbO2 phase with a distorted rutile structure, which can be described as body-centered tetragonal. The a lattice parameter of NbO2 was determined to be ˜13.8 Å in good agreement with neutron diffraction results published in the literature. Films grown on LSAT (111) at lower oxygen pressure produced the NbO phase with a defective rock salt cubic structure. The NbO lattice parameter was determined to be a ≈ 4.26 Å. The film phase/structure identification from TEM was in good agreement with in situ x-ray photoelectron spectroscopy measurements that confirmed the dioxide and monoxide phases, respectively. The atomic structure of the NbO2/STO and NbO/LSAT interfaces was determined based on comparisons between high-resolution electron micrographs and image simulations.

  13. Role of film stoichiometry and interface quality in the performance of (Ba,Sr)TiO3 tunable capacitors with high figures of merit

    Science.gov (United States)

    Freeze, Christopher R.; Stemmer, Susanne

    2016-11-01

    Parallel plate capacitors with quality factors exceeding 1000 were fabricated using Ba0.3Sr0.7TiO3 (BST) thin films grown by hybrid molecular beam epitaxy on epitaxial Pt bottom electrodes. The influence of film stoichiometry was investigated by varying the (Ba + Sr)/Ti ratio around the stoichiometric composition. The quality factor is highest for stoichiometric films, but (Ba + Sr)-rich films can be biased to higher fields. Furthermore, two different processes were used to deposit the top electrodes of the parallel plate capacitors. While the quality of the top contact/BST interface did not strongly affect the device quality factor, an enhancement in the dielectric tunability was seen for capacitors with top electrodes deposited at high temperatures, which effectively removes interfacial contamination layers.

  14. X-ray crystal truncation rod scattering from MBE grown (CaF 2-SrF 2)/Si(111) superlattices

    Science.gov (United States)

    Harada, J.; Itoh, Y.; Shimura, T.; Takahashi, I.; Alvarez, J. C.; Sokolov, N. S.

    1994-01-01

    Flouride CaF 2-SrF 2 superlattices (SLs) grown by molecular beam epitaxy have been studied by means of X-ray diffractometry for the first time. The diffraction patterns showed reasonably good crystalline quality of the SLs and a type-B epitaxial relation to the Si(111) substrate. From the analysis of the crystal truncation rod (CTR) profiles, based on the pseudomorphic model, it was obtained that despite the same high temperature (770°C) of formation of the CaF 2/Si(111) interface its structure depended on the growth temperature of the SLs. The shape of the CTR profiles confirmed the existence of the superlattice which consists of one or two monolayer thick SrF 2 layers. Some CaF 2/SrF 2-interface roughness was noticeable.

  15. Nature and Significance of the High-Sr Aleutian Lavas

    Science.gov (United States)

    Yogodzinski, G. M.; Arndt, S.; Turka, J. R.; Kelemen, P. B.; Vervoort, J. D.; Portnyagin, M.; Hoernle, K.

    2011-12-01

    Results of the Western Aleutian Volcano Expedition and German-Russian KALMAR cruises include the discovery of seafloor volcanism at the Ingenstrem Depression and at unnamed seamounts 300 km west of Buldir, the westernmost emergent volcano in the Aleutian arc. These discoveries indicate that the surface expression of active Aleutian volcanism goes below sea level just west of Buldir, but is otherwise continuous along the full length of the arc. Many lavas dredged from western Aleutian seamounts are basalts, geochemically similar to basalts from elsewhere in Aleutians and other arcs (La/Yb 4-8, Sr/Y700 ppm Sr), which are mostly plagioclase-hornblende andesites and dacites with low Y and middle-heavy rare-earth elements, fractionated trace element patterns (Sr/Y=50-200, La/Yb=9-25) and MORB-like isotopes (87Sr/86Sr 0.65) with 1250-1700 ppm Sr, 4-7 ppm Y, low abundances of all rare-earth elements (Laandesites from some emergent volcanoes in the western Aleutians, and mixing arrays indicate that it may be present in all Aleutian lavas (e.g., 87Sr/86Sr vs. La/Yb or Sr/Y); however, radiogenic Pb and Sr from subducted sediment renders the high-Sr endmember isotopically invisible in most central and eastern Aleutian lavas. The geochemistry of small monogenetic sea-floor volcanoes--especially those in the back-arc--may be the best opportunity to identify the high-Sr endmember in central and eastern Aleutian locations. The existence of primitive, high-silica lavas in the western Aleutians, where the subducting plate is probably unusually hot, may also provide key observations toward an improved understanding of high-Mg# andesites and dacites from other hot-slab locations, especially in the Cascades and Central Mexico. [1] Zimmer et al., 2010, J. Petrology, v. 51, p. 2411

  16. Implementation of depolarization due to beam-beam effects in the beam-beam interaction simulation tool GUINEA-PIG++

    Science.gov (United States)

    Rimbault, C.; Le Meur, G.; Blampuy, F.; Bambade, P.; Schulte, D.

    2009-12-01

    Depolarization is a new feature in the beam-beam simulation tool GUINEA-PIG++ (GP++). The results of this simulation are studied and compared with another beam-beam simulation tool, CAIN, considering different beam parameters for the International Linear Collider (ILC) with a centre-of-mass energy of 500 GeV.

  17. X-ray micro-beam characterization of a small pixel spectroscopic CdTe detector

    Science.gov (United States)

    Veale, M. C.; Bell, S. J.; Seller, P.; Wilson, M. D.; Kachkanov, V.

    2012-07-01

    A small pixel, spectroscopic, CdTe detector has been developed at the Rutherford Appleton Laboratory (RAL) for X-ray imaging applications. The detector consists of 80 × 80 pixels on a 250 μm pitch with 50 μm inter-pixel spacing. Measurements with an 241Am γ-source demonstrated that 96% of all pixels have a FWHM of better than 1 keV while the majority of the remaining pixels have FWHM of less than 4 keV. Using the Diamond Light Source synchrotron, a 10 μm collimated beam of monochromatic 20 keV X-rays has been used to map the spatial variation in the detector response and the effects of charge sharing corrections on detector efficiency and resolution. The mapping measurements revealed the presence of inclusions in the detector and quantified their effect on the spectroscopic resolution of pixels.

  18. Quasi-monoenergetic positron beam generation from ultra-intense laser-matter interactions

    Science.gov (United States)

    Nakamura, Tatsufumi; Hayakawa, Takehito

    2016-10-01

    In ultra-intense laser-matter interactions in which the radiation reaction effect plays an important role, γ-rays are effectively generated that are intense, collimated, and of short duration. These γ-rays propagate through the target, which results in the electron-positron pair creation caused by the interaction of the γ-rays with the nuclear electric fields. The positron beam thus generated has several unique features; it is quasi-monoenergetic in nature with a peak energy of hundreds of MeV, well collimated, and of ultra-short duration. Based on the numerical simulations, the dependences of the number and monochromaticity of the positrons on the laser and target parameters are explored, which leads to the proposal of a new type of the laser-driven positron source.

  19. Beam distribution reconstruction simulation for electron beam probe

    CERN Document Server

    Feng, Yongchun; Li, Peng; Kang, Xincai; Yin, Yan; Liu, Tong; You, Yaoyao; Chen, Yucong; Zhao, Tiecheng; Xu, Zhiguo; Wang, Yanyu; Yuan, Youjin

    2016-01-01

    Electron beam probe (EBP) is a new principle detector, which makes use of a low-intensity and low-energy electron beam to measure the transverse profile, bunch shape, beam neutralization and beam wake field of an intense beam with small dimensions. While can be applied to many aspects, we limit our analysis to beam distribution reconstruction. This kind of detector is almost non-interceptive for all of the beam and does not disturb the machine environment. In this paper, we present the theoretical aspects behind this technique for beam distribution measurement and some simulation results of the detector involved. First, a method to obtain parallel electron beam is introduced and a simulation code is developed. And then, EBP as a profile monitor for dense beam is simulated using fast scan method under various target beam profile, such as KV distribution, waterbag distribution, parabolic distribution, Gaussian distribution and halo distribution. Profile reconstruction from the deflected electron beam trajectory...

  20. Linearizing Intra-Train Beam-Beam Deflection Feedback

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.R.; /SLAC

    2006-02-22

    Beam-beam deflection feedback acting within the crossing time of a single bunch train may be needed to keep linear collider beams colliding at high luminosity. In a short-pulse machine such as the Next Linear Collider (NLC) this feedback must converge quickly to be useful. The non-linear nature of beam-beam deflection vs. beam-beam offset in these machines precludes obtaining both rapid convergence and a stable steady-state lock to beam offsets with a linear feedback algorithm. We show that a simply realizable programmable non-linear amplifier in the feedback loop can linearize the feedback loop, approximately compensating the beam-beam deflection non-linearity. Performance of a prototype non-linear amplifier is shown. Improvement of convergence and stability of the beam-beam feedback loop is simulated.

  1. Beaming teaching application

    DEFF Research Database (Denmark)

    Markovic, Milos; Madsen, Esben; Olesen, Søren Krarup;

    2012-01-01

    BEAMING is a telepresence research project aiming at providing a multimodal interaction between two or more participants located at distant locations. One of the BEAMING applications allows a distant teacher to give a xylophone playing lecture to the students. Therefore, rendering of the xylophon...

  2. Ionization beam scanner

    CERN Multimedia

    CERN PhotoLab

    1973-01-01

    Inner structure of an ionization beam scanner, a rather intricate piece of apparatus which permits one to measure the density distribution of the proton beam passing through it. On the outside of the tank wall there is the coil for the longitudinal magnetic field, on the inside, one can see the arrangement of electrodes creating a highly homogeneous transverse electric field.

  3. Microstructural investigation of Sr-modified Al-15 wt%Si alloys in the range from micrometer to atomic scale.

    Science.gov (United States)

    Timpel, M; Wanderka, N; Vinod Kumar, G S; Banhart, J

    2011-05-01

    Strontium-modified Al-15 wt%Si casting alloys were investigated after 5 and 60 min of melt holding. The eutectic microstructures were studied using complementary methods at different length scales: focused ion beam-energy selective backscattered tomography, transmission electron microscopy and 3D atom probe. Whereas the samples after 5 min of melt holding show that the structure of eutectic Si changes into a fine fibrous morphology, the increase of prolonged melt holding (60 min) leads to the loss of Sr within the alloy with an evolution of an unmodified eutectic microstructure displaying coarse interconnected Si plates. Strontium was found at the Al/Si eutectic interfaces on the side of the eutectic Al region, measured by 3D atom probe. The new results obtained using 3D atom probe shed light on the location of Sr within the Al-Si eutectic microstructure.

  4. Ferromagnetic erbium studied by {mu}SR

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, O. [Uppsala Univ. (Sweden). Dept. of Theoretical Physics; Lidstroem, E. [Uppsala Univ. (Sweden). Dept. of Theoretical Physics; Ekstroem, M. [Uppsala Univ. (Sweden). Dept. of Theoretical Physics; Waeppling, R. [Uppsala Univ. (Sweden). Dept. of Theoretical Physics; Asch, L. [Technische Univ. Muenchen, Garching (Germany). Physik-Department; Kalvius, G.M. [Technische Univ. Muenchen, Garching (Germany). Physik-Department

    1997-04-01

    The ferromagnetic cone phase of erbium has been studied with {mu}SR. Two processing muon signals were observed with nearly equal intensities at T {approx} 15 K. At lower temperatures, one of the signals is gradually reduced and disappeared below 5 K. The two observed muon frequencies and their depolarisation behaviour show that the magnetic structure deduced from neutron and X-ray scattering must be modified and that a ``squaring up`` of the structure is likely to occur as the temperature is lowered. (orig.).

  5. Ferromagnetic erbium studied by {mu}SR

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Ola; Lidstroem, Erik; Ekstroem, Mikael; Waeppling, Roger [Uppsala University, Department of Physics (Sweden); Asch, L.; Kalvius, G.M. [TU Muenich, Physics Department (Germany)

    1997-04-15

    The ferromagnetic cone phase of erbium has been studied with {mu}SR. Two precessing muon signals were observed with nearly equal intensities at T {approx} 15 K. At lower temperatures, one of the signals is gradually reduced and disappeared below 5 K. The two observed muon frequencies and their depolarisation behaviour show that the magnetic structure deduced from neutron and X-ray scattering must be modified and that a 'squaring up' of the structure is likely to occur as the temperature is lowered.

  6. mu. /sup +/SR in imperfect solids

    Energy Technology Data Exchange (ETDEWEB)

    Huang, C.Y.; Huber, D.L.

    1978-01-01

    The use of ..mu../sup +/SR as a probe of point defects in metals is discussed. The importance of separating the effects due to the presence of the muon from those intrinsic to the defect-host system is stressed. It is suggested that studies of magnetic impurities in nonmagnetic hosts may yield data which are relatively probe-independent. A theoretical analysis of the depolarization of muons coupled to magnetic impurities is outlined. It is pointed out that measurements of the magnetic field dependence of the depolarization rate can give information about impurity spin correlation time.

  7. Muon Beam at the Fermilab Test Beam Area

    CERN Document Server

    Denisov, Dmitri; Lukić, Strahinja; Ujić, Predrag

    2016-01-01

    The intensities and profiles of the muon beam behind the beam dump of the Fermilab test beam area when the facility is running in the "pion" beam mode are measured and summarized in this note. This muon beam with momenta in the range 10 - 50 GeV/c provides an opportunity to perform various measurements in parallel with other users of the test beam area.

  8. Mechanically reinforced glass beams

    DEFF Research Database (Denmark)

    Nielsen, Jens Henrik; Olesen, John Forbes

    2007-01-01

    The use of glass as a load carrying material in structural elements is rarely seen even though glass is a popular material for many architects. This is owed to the unreliable and low tensile strength, which is due to surface flaws and high brittleness of the material. These properties lead...... to breakage without any warning or ductility, which can be catastrophic if no precautions are taken. One aspect of this issue is treated here by looking at the possibility of mechanically reinforcing glass beams in order to obtain ductile failure for such a structural component. A mechanically reinforced...... laminated float glass beam is constructed and tested in four-point bending. The beam consist of 4 layers of glass laminated together with a slack steel band glued onto the bottom face of the beam. The glass parts of the tested beams are \\SI{1700}{mm} long and \\SI{100}{mm} high, and the total width of one...

  9. Beam director design report

    Energy Technology Data Exchange (ETDEWEB)

    Younger, F.C.

    1986-08-01

    A design and fabrication effort for a beam director is documented. The conceptual design provides for the beam to pass first through a bending and focusing system (or ''achromat''), through a second achromat, through an air-to-vacuum interface (the ''beam window''), and finally through the vernier steering system. Following an initial concept study for a beam director, a prototype permanent magnet 30/sup 0/ beam-bending achromat and prototype vernier steering magnet were designed and built. In volume II, copies are included of the funding instruments, requests for quotations, purchase orders, a complete set of as-built drawings, magnetic measurement reports, the concept design report, and the final report on the design and fabrication project. (LEW)

  10. Entangled vector vortex beams

    Science.gov (United States)

    D'Ambrosio, Vincenzo; Carvacho, Gonzalo; Graffitti, Francesco; Vitelli, Chiara; Piccirillo, Bruno; Marrucci, Lorenzo; Sciarrino, Fabio

    2016-09-01

    Light beams having a vectorial field structure, or polarization, that varies over the transverse profile and a central optical singularity are called vector vortex (VV) beams and may exhibit specific properties such as focusing into "light needles" or rotation invariance. VV beams have already found applications in areas ranging from microscopy to metrology, optical trapping, nano-optics, and quantum communication. Individual photons in such beams exhibit a form of single-particle quantum entanglement between different degrees of freedom. On the other hand, the quantum states of two photons can be also entangled with each other. Here, we combine these two concepts and demonstrate the generation of quantum entanglement between two photons that are both in VV states: a form of entanglement between two complex vectorial fields. This result may lead to quantum-enhanced applications of VV beams as well as to quantum information protocols fully exploiting the vectorial features of light.

  11. BEAMS3D Neutral Beam Injection Model

    Science.gov (United States)

    McMillan, Matthew; Lazerson, Samuel A.

    2014-09-01

    With the advent of applied 3D fields in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous slowing down, and pitch angle scattering are modeled with the ADAS atomic physics database. Elementary benchmark calculations are presented to verify the collisionless particle orbits, NBI model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields. Notice: this manuscript has been authored by Princeton University under Contract Number DE-AC02-09CH11466 with the US Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes.

  12. Magnetism without magnetic ions in non-magnetic perovskites SrTiO 3, SrZrO 3 and SrSnO 3

    Science.gov (United States)

    Bannikov, V. V.; Shein, I. R.; Kozhevnikov, V. L.; Ivanovskii, A. L.

    Using the full-potential linearized augmented plane-wave (FP-LAPW) method with the generalized gradient approximation (GGA) for the exchange-correlation potential, we studied spin polarization induced by replacement of oxygen atoms by non-magnetic 2p impurities (B, C and N) in non-magnetic cubic SrMO 3 perovskites, where M=Ti, Zr and Sn. The results show that the magnetization may appear because of the spin-split impurity bands inside the energy gap of the insulating SrMO 3 matrix. Large magnetic moments are found for the impurity centers. Smaller magnetic moments are induced on the oxygen atoms around impurities. It is shown that SrTiO 3:C and SrSnO 3:C should be magnetic semiconductors while other compounds in this series (SrTiO 3:B, SrTiO 3:N and SrZrO 3:C) are expected to exhibit magnetic half-metallic or pseudo-half-metallic properties.

  13. Magnetism without magnetic ions in non-magnetic perovskites SrTiO{sub 3}, SrZrO{sub 3} and SrSnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Bannikov, V.V.; Shein, I.R.; Kozhevnikov, V.L. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620041 Ekaterinburg (Russian Federation); Ivanovskii, A.L. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620041 Ekaterinburg (Russian Federation)], E-mail: ivanovskii@ihim.uran.ru

    2008-03-15

    Using the full-potential linearized augmented plane-wave (FP-LAPW) method with the generalized gradient approximation (GGA) for the exchange-correlation potential, we studied spin polarization induced by replacement of oxygen atoms by non-magnetic 2p impurities (B, C and N) in non-magnetic cubic SrMO{sub 3} perovskites, where M=Ti, Zr and Sn. The results show that the magnetization may appear because of the spin-split impurity bands inside the energy gap of the insulating SrMO{sub 3} matrix. Large magnetic moments are found for the impurity centers. Smaller magnetic moments are induced on the oxygen atoms around impurities. It is shown that SrTiO{sub 3}:C and SrSnO{sub 3}:C should be magnetic semiconductors while other compounds in this series (SrTiO{sub 3}:B, SrTiO{sub 3}:N and SrZrO{sub 3}:C) are expected to exhibit magnetic half-metallic or pseudo-half-metallic properties.

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

    Directory of Open Access Journals (Sweden)

    H. Wang

    2016-03-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-03-10

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

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

    Science.gov (United States)

    Wang, H.; Otsu, H.; Sakurai, H.; Ahn, D. S.; Aikawa, M.; Doornenbal, P.; Fukuda, N.; Isobe, T.; Kawakami, S.; Koyama, S.; Kubo, T.; Kubono, S.; Lorusso, G.; Maeda, Y.; Makinaga, A.; Momiyama, S.; Nakano, K.; Niikura, M.; Shiga, Y.; Söderström, P.-A.; Suzuki, H.; Takeda, H.; Takeuchi, S.; Taniuchi, R.; Watanabe, Ya.; Watanabe, Yu.; Yamasaki, H.; Yoshida, K.

    2016-03-01

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

  17. Photosynthesis-dependent and -independent responses of stomata to blue, red and green monochromatic light: differences between the normally oriented and inverted leaves of sunflower.

    Science.gov (United States)

    Wang, Yin; Noguchi, Ko; Terashima, Ichiro

    2011-03-01

    The effects of growth light environment on stomatal light responses were analyzed. We inverted leaves of sunflower (Helianthus annuus) for 2 weeks until their full expansion, and measured gas exchange properties of the adaxial and abaxial sides separately. The sensitivity to light assessed as the increase in stomatal conductance was generally higher in the abaxial stomata than in the adaxial stomata, and these differences could not be completely changed by the inversion treatment. We also treated the leaves with DCMU to inhibit photosynthesis and evaluated the photosynthesis-dependent and -independent components of stomatal light responses. The red light response of stomata in both normally oriented and inverted leaves relied only on the photosynthesis-dependent component. The blue light response involved both the photosynthesis-dependent and photosynthesis-independent components, and the relative contributions of the two components differed between the normally oriented and inverted leaves. A green light response was observed only in the abaxial stomata, which also involved the photosynthesis-dependent and photosynthesis-independent components, strongly suggesting the existence of a green light receptor in sunflower leaves. Moreover, acclimation of the abaxial stomata to strong direct light eliminated the photosynthesis-independent component in the green light response. The results showed that stomatal responses to monochromatic light change considerably in response to growth light environment, although some of these responses appear to be determined inherently. © The Author 2011. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

  18. Compact High-Repetition-Rate Monochromatic Terahertz Source Based on Difference Frequency Generation from a Dual-Wavelength Nd:YAG Laser and DAST Crystal

    Science.gov (United States)

    Zhong, Kai; Mei, Jialin; Wang, Maorong; Liu, Pengxiang; Xu, Degang; Wang, Yuye; Shi, Wei; Yao, Jianquan; Teng, Bing; Xiao, Yong

    2017-01-01

    Although high-repetition-rate dual-wavelength Nd:YAG lasers at 1319 and 1338 nm have been realized for quite a long time, we have employed it in generating monochromatic terahertz (THz) wave in this paper for the first time. The dual-wavelength laser was LD-end-pumped and acousto-optically (AO) Q-switched with the output power of watt level operating at different repetition rates from 5.5 to 30 kHz. Using a 0.6-mm-thick organic nonlinear crystal DAST for difference frequency generation (DFG), a compact terahertz source was achieved at 3.28 THz. The maximum average output power was about 0.58 μW obtained at a repetition rate of 5.5 kHz, corresponding to the conversion efficiency of about 6.4 × 10-7. The output power scaling is still feasible with higher pump power and a longer nonlinear DFG crystal. Owing to the compactness of the dual-wavelength laser and the nonlinear crystal, a palm-top terahertz source is expected for portable applications such as imaging and so on.

  19. Absorption of monochromatic and narrow band radiation in the visible and near IR by both mitochondrial and non-mitochondrial photoacceptors results in photobiomodulation.

    Science.gov (United States)

    Passarella, Salvatore; Karu, Tiina

    2014-11-01

    In addition to the major functions performed by in the cell, mitochondria play a major role in cell-light interaction. Accordingly it is generally accepted that mitochondria are crucial in cell photobiomodulation; however a variety of biomolecules themselves proved to be targets of light irradiation. We describe whether and how mitochondria can interact with monochromatic and narrow band radiation in the red and near IR optical regions with dissection of both structural and functional effects likely leading to photobiostimulation. Moreover we also report that a variety of biomolecules localized in mitochondria and/or in other cell compartments including cytochrome c oxidase, some proteins, nucleic acids and adenine nucleotides are light sensitive with major modifications in their biochemistry. All together the reported investigations show that the elucidation of the mechanism of the light interaction with biological targets still remains to be completed, this needing further research, however the light sensitivity of a variety of molecules strongly suggests that photobiomodulation could be used in both in photomedicine and in biotechnology.

  20. A new technique to study transient conductivity under pulsed monochromatic light in Cr-doped GaAs using acoustoelectric voltage measurement

    Science.gov (United States)

    Tabib-Azar, Massood

    1991-01-01

    The transient conductivity of high-resistivity Bridgman-grown Cr-doped GaAs under pulsed monochromatic light is monitored using transverse acoustoelectric voltage (TAV) at 83 K. Keeping the photon flux constant, the height and transient time constant at the TAV are used to calculate the energy dependence of the trap density and its cross section, respectively. Two prominent trap profiles with peak trap densities of approximately 10 to the 17th/cu cm eV near the valence and the conduction bands are detected. These traps have very small capture cross sections in the range of 10 to the -23 to 10 to the -21st cm sq. A phenomenon similar to the persistent photoconductivity with transient time constants in excess of a few seconds in high-resistivity GaAs at T = 83 K is also detected using this technique. These long relaxation times are readily explained by the spatial separation of the photo-excited electron-hole pairs and the small capture cross section and large density of trap distribution near the conduction band.

  1. Rb-Sr and Sm-Nd Ages of Zagami DML and SR Isotopic Heterogeneity in Zagami

    Science.gov (United States)

    Nyquist, L.aurenceE.; Shih, C.-Y.; Reese, Y. D.

    2010-01-01

    Zagami contains lithologic heterogeneity suggesting that it did not form in a homogeneous, thick lava flow [1]. We have previously investigated the Sr and Nd isotopic systematics of Coarse-Grained (CG) and Fine-Grained (FG) lithologies described by [2]. Both appear to belong to Normal Zagami (NZ) [1,3], but their initial Sr-isotopic compositions differ [4,5]. Here we report new analyses of the Dark Mottled Lithology (DML, [3]) that show its age and initial Sr and Nd isotopic compositions to be identical within error limits with those of CG, but Sr initial isotopic compositions differ from those of FG.

  2. Colliding. gamma. e and. gamma gamma. beams from single-pass e/sup +/e/sup -/ accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, I.F.; Kotkin, G.L.; Serbo, V.G.; Tel' nov, V.I.

    1983-08-01

    A detailed discussion is given of the main characteristics of ..gamma..e and ..gamma gamma.. collisions in the scheme previously proposed by the authors for obtaining colliding ..gamma..e and ..gamma gamma.. beams on the basis of the planned linear accelerators with e/sup +/e/sup -/ colliding beams VLEPP and SLC. It is proposed to obtain intense ..gamma.. beams with energy ..omega..approx.E/sub e/> or =50 GeV by scattering of laser light focused onto the electron beams of these accelerators. In the case when the maximum luminosity is achieved, L/sub gammae/approx.L/sub e/e or L/sub gammagamma/approx.L/sub e/e, the distribution of the luminosity in the invariant mass of the ..gamma..e or ..gamma gamma.. system is broad. Monochromatization of the collisions to a level 5--10% is possible. It involves a decrease of luminosity and is most efficient for use of electrons and laser photons with helicities of opposite sign. Examples of interesting physics problems for the proposed ..gamma..e and ..gamma gamma.. beams are given.

  3. New x-ray parallel beam facility XPBF 2.0 for the characterization of silicon pore optics

    Science.gov (United States)

    Krumrey, Michael; Müller, Peter; Cibik, Levent; Collon, Max; Barrière, Nicolas; Vacanti, Giuseppe; Bavdaz, Marcos; Wille, Eric

    2016-07-01

    A new X-ray parallel beam facility (XPBF 2.0) has been installed in the laboratory of the Physikalisch-Technische Bundesanstalt at the synchrotron radiation facility BESSY II in Berlin to characterize silicon pore optics (SPOs) for the future X-ray observatory ATHENA. As the existing XPBF which is operated since 2005, the new beamline provides a pencil beam of very low divergence, a vacuum chamber with a hexapod system for accurate positioning of the SPO to be investigated, and a vertically movable CCD-based camera system to register the direct and the reflected beam. In contrast to the existing beamline, a multilayer-coated toroidal mirror is used for beam monochromatization at 1.6 keV and collimation, enabling the use of beam sizes between about 100 μm and at least 5 mm. Thus the quality of individual pores as well as the focusing properties of large groups of pores can be investigated. The new beamline also features increased travel ranges for the hexapod to cope with larger SPOs and a sample to detector distance of 12 m corresponding to the envisaged focal length of ATHENA.

  4. Multi-Beam Optical Tweezers

    OpenAIRE

    Glückstad, Jesper; Eriksen, Rene Lynge; Hanson, Steen Grüner

    2003-01-01

    A set of multi-beam electromagnetic tweezers is provided comprising a multi-beam generator for emission of a plurality of electromagnetic beams, at least some of the electromagnetic beams intersecting each other, or, having an individually controlled polarization whereby the position and/or angular orientation of a plurality of micro-objects may be individually controlled.A set of multi-beam electromagnetic tweezers is provided comprising a multi-beam generator for emission of a plurality of ...

  5. Beam Imaging and Luminosity Calibration

    CERN Document Server

    Klute, Markus; Salfeld-Nebgen, Jakob

    2016-01-01

    We discuss a method to reconstruct two-dimensional proton bunch densities using vertex distributions accumulated during LHC beam-beam scans. The $x$-$y$ correlations in the beam shapes are studied and an alternative luminosity calibration technique is introduced. We demonstrate the method on simulated beam-beam scans and estimate the uncertainty on the luminosity calibration associated to the beam-shape reconstruction to be below 1\\%.

  6. Dielectric relaxation in Sr modified PST ceramics

    Science.gov (United States)

    Sen, S.; Choudhary, R. N. P.

    2007-06-01

    Nanocrystalline powders of strontium modified PbSn0.15Ti0.85O3 (PST) having the formula Pb0.94Sr0.06Sn0.15 have been synthesized by a precursor solution method. The electrical behavior of Pb0.94Sr0.06Sn0.15Ti0.85O3 sintered pellets has been studied by complex impedance spectroscopy analysis. The plot of the real and imaginary parts of the impedance shows that the semicircle exhibits a depression degree with a distribution of relaxation time. The modulus curve indicates the possibility of non-exponential type conductivity. The values of the activation energy calculated from both plots of Z” and M”, are 1.06 and 1.09 eV, which reveals that the species responsible for conduction are same. It also confirms that oxygen vacancies play an important role in conduction. The non-overlapping of the peaks in the plot of M”/M”max and Z”/Z”max as a function of logarithmic frequency measured at 350 °C indicates short-range conduction. The compounds exhibit a negative temperature coefficient of resistance with an α value of -5×10-2 °C at 375 °C. The frequency (ω) dependence of conductivity satisfies the ωn power law. The variation of n with temperature suggests that ac conduction is due to small polaron tunneling.

  7. Idraparinux sodium: SANORG 34006, SR 34006.

    Science.gov (United States)

    2004-01-01

    Idraparinux sodium [SANORG 34006, SR 34006], a synthetic, anti Xa pentasaccharide and analogue of SR 32701 and fondaparinux sodium, was in development with Sanofi (now Sanofi-Synthélabo) and Organon (Akzo Nobel) in Europe and the USA (now Sanofi-Synthélabo alone). It may have potential in the treatment and secondary prevention of thrombosis, especially deep-vein thrombosis (DVT). Because of the long duration of action of idraparinux sodium, it may be suitable for once-weekly administration. In January 2004, Sanofi-Synthélabo announced it was to acquire, before the end of the first quarter 2004, all the rights of Organon relating to idraparinux sodium, subject to approval of the regulatory authorities. Sanofi-Synthélabo is to make payments to Organon based on future sales. Idraparinux sodium has completed phase IIb development with the PERSIST study and it is in phase III clinical trials. In June 2003, Organon announced the initiation of pivotal phase III studies as a once-weekly treatment of DVT and pulmonary embolism (PE), and for the prevention of stroke in patients with atrial fibrillation. The AMADEUS study will focus on patients with atrial fibrillation while the Van Gogh PE, Van Gogh DVT and the Van Gogh extension (EXT) will focus on patients with DVT or PE.

  8. Temperature-Dependent Structure of Epitaxial (Ba,Sr)TiO3 Films Grown on SrRuO3-Covered SrTiO3 Substrates

    Institute of Scientific and Technical Information of China (English)

    HE Jia-Qing; E. VASCO; R. DITTMANN; WANG Ren-Hui

    2006-01-01

    @@ Growth dynamics of epitaxial (Ba, Sr)TiO3 thin films deposited at different temperatures on SrRuOa/SrTiO3substrates by pulsed laser deposition is investigated by transmission electron microscopy. The films exhibit a layered structure comprising sublayers with distinctive features in regard to the remaining strain, density of misfit dislocations and/or lattice defects, and growth habit. We correlate these temperature-dependent features with the predominant misfit-strain relaxation mechanisms for each one of the detected growth regimes. The thickness dependence of the film structure is discussed within the framework of the predictions for a kinetically modified Stranski-Krastanov growth mode.

  9. Multi-Beam Optical Tweezers

    DEFF Research Database (Denmark)

    2003-01-01

    A set of multi-beam electromagnetic tweezers is provided comprising a multi-beam generator for emission of a plurality of electromagnetic beams, at least some of the electromagnetic beams intersecting each other, or, having an individually controlled polarization whereby the position and/or angular...... orientation of a plurality of micro-objects may be individually controlled.A set of multi-beam electromagnetic tweezers is provided comprising a multi-beam generator for emission of a plurality of electromagnetic beams, at least some of the electromagnetic beams intersecting each other, or, having...

  10. The third-order optical nonlinearity of the stainless steel doped SrTiO3 thin film grown by L-MBE

    Institute of Scientific and Technical Information of China (English)

    Lifeng Liu(刘丽峰); Yiyan Fei(费义艳); Haizhong Guo(郭海中); Wenfeng Xiang(相文峰); Huibin Lü(吕惠宾); Zhenghao Chen(陈正豪)

    2003-01-01

    Stainless steel-doped SrTiO3 thin films were fabricated by laser molecular beam epitaxy (L-MBE).Nonlinear optical property of the thin film was measured by the single beam Z-scan technique at thewavelength of 532 nm. Two two-phonon absorption coefficient and nonlinear refractive index weredetermined to be 9.37 × 10-7 m/W and 1.55 × 10-6 esu, respectively. The merit figure T was calculatedto be 1.8, satisfying condition T < 2 for an optical switch. The thin film has a very promising prospectfor the applications in optical device.

  11. Simulations of beam-beam and beam-wire interactions in RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung J.; Sen, Tanaji; /Fermilab; Abreu, Natalia P.; Fischer, Wolfram; /Brookhaven

    2009-02-01

    The beam-beam interaction is one of the dominant sources of emittance growth and luminosity lifetime deterioration. A current carrying wire has been proposed to compensate long-range beam-beam effects in the LHC and strong localized long-range beam-beam effects are experimentally investigated in the RHIC collider. Tune shift, beam transfer function, and beam loss rate are measured in dedicated experiments. In this paper, they report on simulations to study the effect of beam-wire interactions based on diffusive apertures, beam loss rates, and beam transfer function using a parallelized weak-strong beam simulation code (BBSIMC). The simulation results are compared with measurements performed in RHIC during 2007 and 2008.

  12. Precision measurement of transverse velocity distribution of a strontium atomic beam

    Science.gov (United States)

    Gao, F.; Liu, H.; Xu, P.; Tian, X.; Wang, Y.; Ren, J.; Wu, Haibin; Chang, Hong

    2014-02-01

    We measure the transverse velocity distribution in a thermal Sr atomic beam precisely by velocity-selective saturated fluorescence spectroscopy. The use of an ultrastable laser system and the narrow intercombination transition line of Sr atoms mean that the resolution of the measured velocity can reach 0.13 m/s, corresponding to 90 μK in energy units. The experimental results are in very good agreement with the results of theoretical calculations. Based on the spectroscopic techniques used here, the absolute frequency of the intercombination transition of 88Sr is measured using an optical-frequency comb generator referenced to the SI second through an H maser, and is given as 434 829 121 318(10) kHz.

  13. Precision measurement of transverse velocity distribution of a strontium atomic beam

    Directory of Open Access Journals (Sweden)

    F. Gao

    2014-02-01

    Full Text Available We measure the transverse velocity distribution in a thermal Sr atomic beam precisely by velocity-selective saturated fluorescence spectroscopy. The use of an ultrastable laser system and the narrow intercombination transition line of Sr atoms mean that the resolution of the measured velocity can reach 0.13 m/s, corresponding to 90 μK in energy units. The experimental results are in very good agreement with the results of theoretical calculations. Based on the spectroscopic techniques used here, the absolute frequency of the intercombination transition of 88Sr is measured using an optical-frequency comb generator referenced to the SI second through an H maser, and is given as 434 829 121 318(10 kHz.

  14. Tagged fast neutron beams En > 6 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Favela, F.; Huerta, A.; Santa Rita, P.; Ramos, A. T.; Lucio, O. de; Andrade, E.; Ortiz, M. E.; Araujo, V.; Chávez, E., E-mail: chavez@fisica.unam.mx [Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, México D. F. 01000 México (Mexico); Acosta, L. [Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, México D. F. 01000 México (Mexico); INFN-Sezione di Catania, Via Santa Sofia 64 I-95123, Catania (Italy); Murillo, G.; Policroniades, R. [Departamento de Aceleradores, Instituto Nacional de Investigaciones Nucleares, Carr. México-Toluca S/N, Ocoyoacac, Edo. Méx., 52750 (Mexico); Varela, A. [Instituto de Ciencias de la Atmósfera, UNAM (Mexico)

    2015-07-23

    Controlled flux of neutrons are produced through the {sup 14}N(d,n){sup 15}O nuclear reaction. Deuteron beams (2-4 MeV) are delivered by the CN-Van de Graaff accelerator and directed with full intensity to our Nitrogen target at SUGAR (SUpersonic GAs jet taRget). Each neutron is electronically tagged by the detection of the associated{sup 15}O. Its energy and direction are known and “beams” of fast monochromatic tagged neutrons (E{sub n}> 6 MeV) are available for basic research and applied work. MONDE is a large area (158 × 63 cm{sup 2}) plastic scintillating slab (5 cm thick), viewed by 16 PMTs from the sides. Fast neutrons (MeV) entering the detector will produce a recoiling proton that induces a light spark at the spot. Signals from the 16 detectors are processed to deduce the position of the spark. Time logic signals from both the {sup 15}O detector and MONDE are combined to deduce a time of flight (TOF) signal. Finally, the position information together with the TOF yields the full momentum vector of each detected neutron.

  15. Variations in seawater Sr/Ca recorded in deep-sea bamboo corals

    Science.gov (United States)

    Hill, T. M.; Lavigne, M.; Spero, H. J.; Guilderson, T.; Gaylord, B.; Clague, D.

    2012-09-01

    A depth transect of deep-sea bamboo corals along the California margin provides evidence that coral strontium to calcium ratios (Sr/Cacoral) record seawater Sr/Ca ratios (Sr/Casw). A calibration was constructed utilizing Sr/Cacoral ratios and previously published Pacific Sr/Casw data (R2 = 0.53, n = 12, p < 0.01): Sr/Cacoral (mmol/mol) = 4.62*Sr/Casw (mmol/mol) - 36.64. Sr/Casw is ultimately governed by the remineralization of Sr-containing shells of surface water-derived marine organisms (e.g., Acantharia) at intermediate water depths. California margin Sr/Cacoral records from 792 and 1295 m document fluctuations in Sr/Casw that appear decadal-scale. These results suggest that Sr/Casw may not be as stable as previously assumed and may be influenced by surface productivity on short timescales.

  16. Beam Purification by Photodetachment

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yuan [ORNL; Beene, James R [ORNL; Havener, Charles C [ORNL; Galindo-Uribarri, Alfredo {nmn} [ORNL; Andersson, P. [University of Gothenburg, Sweden; Lindahl, A. O. [University of Gothenburg, Sweden; Hanstorp, D. [University of Gothenburg, Sweden; Forstner, Dr. Oliver [University of Vienna, Austria; Gottwald, T. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Wendt, K. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany

    2012-01-01

    Ion beam purity is of crucial importance to many basic and applied studies. Selective photodetachment has been proposed to suppress unwanted species in negative ion beams while preserving the intensity of the species of interest. A highly efficient technique based on photodetachment in a gas-filled radio frequency quadrupole ion cooler has been demonstrated. In off-line experiments with stable ions, up to 104 times suppression of the isobar contaminants in a number of interesting radioactive negative ion beams has been demonstrated. For selected species, this technique promises experimental possibilities in studies on exotic nuclei, accelerator mass spectrometry, and fundamental properties of negative atomic and molecular ions.

  17. Beam instrumentation performance overview

    CERN Document Server

    Sapinski, M

    2012-01-01

    The 2011 run has proven that LHC can operate safely and stably with higher bunch intensity and smaller transverse emittance than foreseen in the Technical Design Report. In this presentation the performance of the Beam Position Monitoring (BPM) system is discussed. The improvements to the system, those made during the last year and those expected to be done for 2012 run are presented. The status of the three types of devices measuring the transverse beam emittance, wire scanners (BWS), synchrotron radiation monitors (BSRT) and beam gas ionization monitors (BGI), are shown. The control room applications are reviewed and a set of improvements proposed by the operation team is presented.

  18. Chemistry, growth kinetics, and epitaxial stabilization of Sn2+ in Sn-doped SrTiO3 using (CH36Sn2 tin precursor

    Directory of Open Access Journals (Sweden)

    Tianqi Wang

    2016-12-01

    Full Text Available PbTiO3-based ferroelectrics have impressive electroactive properties, originating from the Pb2+ 6s2 electron lone-pair, which cause large elastic distortion and electric polarization due to cooperative pseudo Jahn-Teller effect. Recently, tin-based perovskite oxide (SnTiO3 containing Sn2+ and a chemistry similar to that of the 6s2 lone-pair has been identified as a thermally stable, environmentally friendly substitute for PbTiO3-based ferroelectrics. However experimental attempts to stabilize Sn2+ on the A-site of perovskite ATiO3 have so far failed. In this work, we report on the growth of atomically smooth, epitaxial, and coherent Sn-alloyed SrTiO3 films on SrTiO3 (001 substrates using a hybrid molecular beam epitaxy approach. With increasing Sn concentration, the out-of-plane lattice parameter first increases in accordance with the Vegard’s law and then decreases for Sn(Sr+Ti+Sn at. % ratio > 0.1 due to the incorporation of Sn2+ at the A-site. Using a combination of high-resolution X-ray photoelectron spectroscopy and density functional calculations, we show that while majority of Sn is on the B-site, there is a quantitatively unknown fraction of Sn being consistent with the A-site occupancy making SrTiO3 polar. A relaxor-like ferroelectric local distortion with monoclinic symmetry, induced by A-site Sn2+, was observed in Sn-doped SrTiO3 with Sn(Sr+Ti+Sn at. % ratio = 0.1 using optical second harmonic generation measurements. The role of growth kinetics on the stability of Sn2+ in SrTiO3 is discussed.

  19. Chemistry, growth kinetics, and epitaxial stabilization of Sn2+ in Sn-doped SrTiO3 using (CH3)6Sn2 tin precursor

    Science.gov (United States)

    Wang, Tianqi; Pitike, Krishna Chaitanya; Yuan, Yakun; Nakhmanson, Serge M.; Gopalan, Venkatraman; Jalan, Bharat

    2016-12-01

    PbTiO3-based ferroelectrics have impressive electroactive properties, originating from the Pb2+ 6s2 electron lone-pair, which cause large elastic distortion and electric polarization due to cooperative pseudo Jahn-Teller effect. Recently, tin-based perovskite oxide (SnTiO3) containing Sn2+ and a chemistry similar to that of the 6s2 lone-pair has been identified as a thermally stable, environmentally friendly substitute for PbTiO3-based ferroelectrics. However experimental attempts to stabilize Sn2+ on the A-site of perovskite ATiO3 have so far failed. In this work, we report on the growth of atomically smooth, epitaxial, and coherent Sn-alloyed SrTiO3 films on SrTiO3 (001) substrates using a hybrid molecular beam epitaxy approach. With increasing Sn concentration, the out-of-plane lattice parameter first increases in accordance with the Vegard's law and then decreases for Sn(Sr+Ti+Sn/) at. % ratio > 0.1 due to the incorporation of Sn2+ at the A-site. Using a combination of high-resolution X-ray photoelectron spectroscopy and density functional calculations, we show that while majority of Sn is on the B-site, there is a quantitatively unknown fraction of Sn being consistent with the A-site occupancy making SrTiO3 polar. A relaxor-like ferroelectric local distortion with monoclinic symmetry, induced by A-site Sn2+, was observed in Sn-doped SrTiO3 with Sn(Sr+Ti+Sn/) at. % ratio = 0.1 using optical second harmonic generation measurements. The role of growth kinetics on the stability of Sn2+ in SrTiO3 is discussed.

  20. Geosphere process report for the safety assessment SR-Site

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, Kristina (ed.) (Kemakta Konsult AB, Stockholm (Sweden))

    2010-11-15

    This report documents geosphere processes identified as relevant to the long-term safety of a KBS-3 repository, and forms an important part of the reporting of the safety assessment SR-Site. The detailed assessment methodology, including the role of the process reports in the assessment, is described in the SR-Site Main report /SKB 2011/