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Sample records for medium energy spin

  1. Spin effects in medium-energy electron-3He scattering

    International Nuclear Information System (INIS)

    van den Brand, J.F.J.; Alarcon, R.; Bauer, T.

    1998-01-01

    New physics can be accessed by scattering polarized electrons from a polarized 3 He internal gas target. It is discussed how the asymmetries for the reactions 3 vector He(vector e,e'), 3 vector He(vector e,e'p), 3 vector He(vector e,e'n), 3 vector He(vector e,e'd), and 3 vector He(vector e,e'pn) may provide precise information on the S' and the D-wave parts of the 3 He ground-state wave function, the neutron form factors, and the role of spin-dependent reaction mechanism effects. The experiment uses up to 900 MeV (polarized) electrons from the AmPS storage ring in Amsterdam, Netherlands, in combination with large acceptance electron and hadron detectors. (orig.)

  2. Spin transport in intermediate-energy heavy-ion collisions as a probe of in-medium spin–orbit interactions

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Yin [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Xu, Jun, E-mail: xujun@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Li, Bao-An [Department of Physics and Astronomy, Texas A& M University-Commerce, Commerce, TX 75429-3011 (United States); Department of Applied Physics, Xi' an Jiao Tong University, Xi' an 710049 (China); Shen, Wen-Qing [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2016-11-15

    The spin up-down splitting of collective flows in intermediate-energy heavy-ion collisions as a result of the nuclear spin–orbit interaction is investigated within a spin- and isospin-dependent Boltzmann–Uehling–Uhlenbeck transport model SIBUU12. Using a Skyrme-type spin–orbit coupling quadratic in momentum, we found that the spin splittings of the directed flow and elliptic flow are largest in peripheral Au+Au collisions at beam energies of about 100–200 MeV/nucleon, and the effect is considerable even in smaller systems especially for nucleons with high transverse momenta. The collective flows of light clusters of different spin states are also investigated using an improved dynamical coalescence model with spin. Our study can be important in understanding the properties of in-medium nuclear spin–orbit interactions once the spin-dependent observables proposed in this work can be measured.

  3. Medium energy inelastic proton-nucleus scattering with spin dependent NN interaction

    International Nuclear Information System (INIS)

    Ahmad, I.; Auger, J.P.

    1981-12-01

    The previously proposed effective profile expansion method for the Glauber multiple scattering model calculation has been extended to the case of proton-nucleus inelastic scattering with spin dependent NN interaction. Using the method which turns out to be computationally simple and of relatively wider applicability, a study of sensitivity of proton-nucleus inelastic scattering calculation to the sometimes neglected momentum transfer dependence of the NN scattering amplitude has been made. We find that the calculated polarization is particularly sensitive in this respect. (author)

  4. Medium effects on spin observables of proton knockout reactions

    International Nuclear Information System (INIS)

    Krein, G.; Maris, T.A.J.; Rodrigues, B.B.; Veit, E.A.

    1994-07-01

    Medium modifications of the properties of bound nucleons and mesons are investigated by means of medium energy quasi free proton knockout reactions with polarized incident protons. The sensitivity of the spin observables of these reactions to modifications of the nucleon and meson properties is studied using the Bonn one-boson exchange model of the nucleon-nucleon interaction. A method proposed to extract the pp analysing power in medium from the (p, 2 p) asymmetries indicates a reduction of this quantity compared to its free space value. This reduction is linked to modifications of masses and coupling constants of the nucleons and mesons in the nucleus. The implications of these modifications for another spin observable to be measured in the future are discussed. (author). 39 refs, 9 figs

  5. Medium effects on spin observables of proton knockout reactions

    Energy Technology Data Exchange (ETDEWEB)

    Krein, G [Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil); Maris, T A.J.; Rodrigues, B B; Veit, E A [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Fisica

    1994-07-01

    Medium modifications of the properties of bound nucleons and mesons are investigated by means of medium energy quasi free proton knockout reactions with polarized incident protons. The sensitivity of the spin observables of these reactions to modifications of the nucleon and meson properties is studied using the Bonn one-boson exchange model of the nucleon-nucleon interaction. A method proposed to extract the pp analysing power in medium from the (p, 2 p) asymmetries indicates a reduction of this quantity compared to its free space value. This reduction is linked to modifications of masses and coupling constants of the nucleons and mesons in the nucleus. The implications of these modifications for another spin observable to be measured in the future are discussed. (author). 39 refs, 9 figs.

  6. On the polarized beam acceleration in medium energy synchrotrons

    International Nuclear Information System (INIS)

    Lee, S.Y.

    1992-01-01

    This lecture note reviews physics of spin motion in a synchrotron, spin depolarization mechanisms of spin resonances, and methods of overcoming the spin resonances during acceleration. Techniques used in accelerating polarized ions in the low/medium energy synchrotrons, such as the ZGS, the AGS, SATURNE, and the KEK PS and PS Booster are discussed. Problems related to polarized proton acceleration with snakes or partial snake are also examined

  7. On the polarized beam acceleration in medium energy synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.Y.

    1992-12-31

    This lecture note reviews physics of spin motion in a synchrotron, spin depolarization mechanisms of spin resonances, and methods of overcoming the spin resonances during acceleration. Techniques used in accelerating polarized ions in the low/medium energy synchrotrons, such as the ZGS, the AGS, SATURNE, and the KEK PS and PS Booster are discussed. Problems related to polarized proton acceleration with snakes or partial snake are also examined.

  8. IV. Workshop on High Energy Spin Physics

    International Nuclear Information System (INIS)

    Nurushev, S.

    1992-01-01

    In this proceedings the results on high energy spin physics are summarized. The theory of spin phenomenon and the experimental results at intermediate energy and at high energy spin physics and new technical developments in polarization experiments are presented

  9. [Medium energy meson research

    International Nuclear Information System (INIS)

    Crowe, K.M.

    1992-01-01

    The activities of this group are primarily concerned with experiments using the Crystal Barrel Detector. This detector is installed and operating at the Low Energy Antiproton Ring (LEAR) at CERN. QCD, the modem theory of the strong interaction, is reasonably well understood at high energies, but unfortunately, low-energy QCD is still not well understood, and is far from being adequately tested. The Crystal Barrel experiments are designed to provide some of the tests. The basic line of research involves meson spectroscopy, analyses bearing on the quark and/or gluon content of nuclear states, and the exploration of mechanisms and rules which govern p bar p annihilation dynamics. The Crystal Barrel Detector detects and identifies charged and neutral particles with a geometric acceptance close to 100%. The principal component of the detector is an array of 1,380 CsI(TI) crystals. These crystals surround a Jet Drift Chamber (JDC), located in a 1.5 Tesla magnetic field, which measures the momentum and dE/dx of charged particles. One of the very interesting physics goals of the detector is a search for exotic mesonic states -- glueballs and hybrids. Annihilation at rest will be studied with both liquid and gaseous hydrogen targets. The gaseous target offers the possibility of triggering on atomic L-shell X rays so that specific initial angular momentum states can be studied.These topics as well as other related topics are discussed in this report

  10. Optical activity via Kerr nonlinearity in a spinning chiral medium

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Anwar Ali, E-mail: anwarali@uom.edu.pk [Department of Physics, University of Malakand at Chakdara Dir(L) (Pakistan); Bacha, Bakht Amin, E-mail: aminoptics@gmail.com [Department of Physics, University of Malakand at Chakdara Dir(L) (Pakistan); Khan, Rahmat Ali, E-mail: rahmat_alipk@yahoo.com [Department of Mathematics, University of Malakand (Pakistan)

    2016-11-11

    Optical activity is investigated in a chiral medium by employing the four level cascade atomic model, in which the optical responses of the atomic medium are studied with Kerr nonlinearity. Light entering into a chiral medium splits into circular birefringent beams. The angle of divergence between the circular birefringent beams and the polarization states of the two light beams is manipulated with Kerr nonlinearity. In the stationary chiral medium the angle of divergence between the circular birefringent beams is calculated to be 1.3 radian. Furthermore, circular birefringence is optically controlled in a spinning chiral medium, where the maximum rotary photon drag angle for left (right) circularly polarized beam is ±1.1 (±1.5) microradian. The change in the angle of divergence between circular birefringent beams by rotary photon drag is calculated to be 0.4 microradian. The numerical results may help to understand image designing, image coding, discovery of photonic crystals and optical sensing technology. - Highlights: • Coherent control of a circular birefringence in a chiral medium is studied. • Angle of divergence between birefringent beams is modified with Kerr nonlinearity. • Rotary photon drag is controlled for birefringent beams and enhanced with Kerr nonlinearity in a spinning medium. • Rotation of the angle of divergence is observed with mechanical rotation of the medium about an axis and modified with Kerr effect. • A change in the angle of divergence is calculated by about a microradian with rotary photon drag.

  11. Hadron photoproduction at medium energy

    International Nuclear Information System (INIS)

    Dainton, J.B.

    1985-04-01

    Results from measurements of multibody photoproduction at medium incident photon energy (2.8 to 4.8 GeV) are presented and discussed. Particular emphasis is placed on topics which are not well understood and which therefore motivate experiments with the upgraded electron accelerator and storage ring ELSA at the University of Bonn, FR Germany. (author)

  12. Medium energy ion scattering (MEIS)

    International Nuclear Information System (INIS)

    Dittmann, K.; Markwitz, A.

    2009-01-01

    This report gives an overview about the technique and experimental study of medium energy ion scattering (MEIS) as a quantitative technique to determine and analyse the composition and geometrical structure of crystalline surfaces and near surface-layers by measuring the energy and yield of the backscattered ions. The use of a lower energy range of 50 to 500 keV accelerated ions impinging onto the target surface and the application of a high-resolution electrostatic energy analyser (ESA) makes medium energy ion scattering spectroscopy into a high depth resolution and surface-sensitive version of RBS with less resulting damage effects. This report details the first steps of research in that field of measurement technology using medium energetic backscattered ions detected by means of a semiconductor radiation detector instead of an ESA. The study of medium energy ion scattering (MEIS) has been performed using the 40 keV industrial ion implanter established at GNS Sciences remodelled with supplementary high voltage insulation for the ion source in order to apply voltages up to 45 kV, extra apertures installed in the beamline and sample chamber in order to set the beam diameter accurately, and a semiconductor radiation detector. For measurement purposes a beam of positive charged helium ions accelerated to an energy of about 80 keV has been used impinging onto target surfaces of lead implanted into silicon (PbSi), scandium implanted into aluminium (ScAl), aluminium foil (Al) and glassy carbon (C). First results show that it is possible to use the upgraded industrial implanter for medium energy ion scattering. The beam of 4 He 2+ with an energy up to 88 keV has been focussed to 1 mm in diameter. The 5 nA ion beam hit the samples under 2 x 10 -8 mbar. The results using the surface barrier detector show scattering events from the samples. Cooling of the detector to liquid nitrogen temperatures reduced the electronic noise in the backscattering spectrum close to zero. A

  13. Spin effects in intermediate-energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Xu Jun; Li Baoan; Xia Yin; Shen Wenqing

    2014-01-01

    In this paper, we report and extend our recent work where the nucleon spin-orbit interaction and its spin degree of freedom were introduced explicitly for the first time in the isospin-dependent Boltzmann-Uehling-Uhlenbeck transport model for heavy-ion reactions. Despite of the significant cancellation of the time-even and time-odd spin-related mean-field potentials from the spin-orbit interaction,an appreciable local spin polarization is observed in heavy-ion collisions at intermediate energies because of the dominating role of the time-odd terms. It is also found that the spin up-down differential transverse flow in heavy-ion collisions is a useful probe of the strength, density dependence, and isospin dependence of the in-medium spin-orbit interaction, and its magnitude is still considerable even at smaller systems. (authors)

  14. Spin energy levels in axial symmetry: spin 4

    Energy Technology Data Exchange (ETDEWEB)

    de Biasi, R S; Portella, P D [Instituto Militar de Engenharia, Rio de Janeiro (Brazil). Secao de Engenharia e Ciencia dos Materiais

    1979-01-01

    The spin energy levels in axial symmetry are presented, in graphical and tabular form, for a spin 4. The levels are calculated for five different angles between the applied field and the symmetry axis 0/sup 0/, 30/sup 0/, 45/sup 0/, 60 and 90/sup 0/.

  15. Spin energy levels in axial symmetry: spin 3/2

    Energy Technology Data Exchange (ETDEWEB)

    de Biasi, R S; Portella, P D [Instituto Militar de Engenharia, Rio de Janeiro (Brazil). Secao de Engenharia e Ciencia dos Materiais

    1977-01-01

    The spin energy levels in axial symmetry are presented, in graphical and tabular form, for a spin 3/2. The levels are calculated for five different angles between the applied field and the symmetry axis: 0/sup 0/, 30/sup 0/, 45/sup 0/, 60/sup 0/ and 90/sup 0/.

  16. Studies in medium energy physics

    International Nuclear Information System (INIS)

    Green, A.; Hoffmann, G.W.; McDonough, J.; Purcell, M.J.; Ray, R.L.; Read, D.E.; Worn, S.D.

    1991-12-01

    This document constitutes the (1991--1992) technical progress report and continuation proposal for the ongoing medium energy nuclear physics research program supported by the US Department of Energy through special Research Grant DE-FG05-88ER40444. The experiments discussed are conducted at the Los Alamos National Laboratory's (LANL) Clinton P. Anderson Meson Physics Facility (LAMPF) and the Alternating Gradient Synchrotron (AGS) facility of the Brookhaven National Laboratory (BNL). The overall motivation for the work discussed in this document is driven by three main objectives: (1) provide hadron-nucleon and hadron-nucleus scattering data which serve to facilitate the study of effective two-body interactions, test (and possibly determine) nuclear structure, and help study reaction mechanisms and dynamics; (2) provide unique, first-of-a-kind ''exploratory'' hadron-nucleus scattering data in the hope that such data will lead to discovery of new phenomena and new physics; and (3) perform precision tests of fundamental interactions, such as rare decay searches, whose observation would imply fundamental new physics

  17. Medium energy elementary particle physics

    International Nuclear Information System (INIS)

    1991-01-01

    This report discusses the following topics: muon beam development at LAMPF; muon physics; a new precision measurement of the muon g-2 value; measurement of the spin-dependent structure functions of the neutron and proton; and meson factories

  18. High energy spin isospin modes in nuclei

    International Nuclear Information System (INIS)

    Chanfray, G.; Ericson, M.

    1984-01-01

    The high energy response of nuclei to a spin-isospin excitation is investigated. We show the existence of a strong contrast between the spin transverse and spin longitudinal responses. The second one undergoes a shadow effect in the Δ region and displays the occurrence of the pionic branch

  19. Microscopic optical potential at medium energies

    International Nuclear Information System (INIS)

    Malecki, A.

    1979-01-01

    The problems concerning a microscopic optical model for the elastic nuclear collisions at medium energies are discussed. We describe the method for constructing the optical potential which makes use of the particular properties of quantum scattering in the eikonal limit. The resulting potential is expressed in terms of the nuclear wave functions and the nucleon-nucleon scattering amplitudes. This potential has a dynamic character since by including the effects of multiple scattering it allows for the possibility of intermediate excitations of the projectile and target nuclei. The use of the potential in the exact wave equation accounts for the most important mechanisms present in the collisions between composite particles. The microscopic optical model was successfully applied in the analysis of elastic scattering of protons and α-particles on atomic nuclei in the energy range of 300-1000 MeV/nucleon. The dynamic optical potential in this case represents a considerable improvement over the eikonal Glauber model and the static optical potential of Watson. The possibilities to extend the microscopic description of the proton-nucleus interaction by considering the spin dependence of the elementary amplitude and the Majorana exchange effects were investigated. (author)

  20. Use of medium energy particles in radiobiology and radiotherapy

    International Nuclear Information System (INIS)

    Larsson, B.

    1984-01-01

    The radiological properties of ion beams are described and their biomedical use reviewed. The special features and potentialities of secondary radiations obtained with medium-energy accelerators for protons of electrons are mentioned, for comparison. Examples are given from work at heavy accelerators which has contributed to our basic knowledge of radiation effects on cells and tissues, or to recent advances in experimental and clinical radiology. The author tries to identify areas where important spin-off contributions from medium-energy physics to the biomedical sciences could be made, or where such contributions would have significant implications for the society. The conclusion is made that medium energy accelerators have great potential in experimental and preclinical research, particularly in neurophysiology and oncology

  1. FERMILAB: High energy spin effects

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1991-03-15

    While many physicists would agree that it is important to study interactions of different isospin states (for example comparing proton and neutron data), many of them also accept as normal data averaged or integrated over ordinary spin. However an ongoing programme at Brookhaven studying elastic scattering (where the incoming particles 'bounce' off each other) produced marked spin effects which are not well understood. Our understanding of particle interactions should not be influenced by which observables are easy to measure and which aren't, and until a clear understanding of spin effects emerges, it is important to continue and extend these studies.

  2. Heavy quark energy loss in nuclear medium

    International Nuclear Information System (INIS)

    Zhang, Benr-Wei; Wang, Enke; Wang, Xin-Nian

    2003-01-01

    Multiple scattering, modified fragmentation functions and radiative energy loss of a heavy quark propagating in a nuclear medium are investigated in perturbative QCD. Because of the quark mass dependence of the gluon formation time, the medium size dependence of heavy quark energy loss is found to change from a linear to a quadratic form when the initial energy and momentum scale are increased relative to the quark mass. The radiative energy loss is also significantly suppressed relative to a light quark due to the suppression of collinear gluon emission by a heavy quark

  3. Medium energy charged particle spectrometer

    International Nuclear Information System (INIS)

    Keppler, E.; Wilken, B.; Richer, K.; Umlauft, G.; Fischer, K.; Winterhoff, H.P.

    1976-10-01

    The charged particle spectrometer E8 on HELIOS A and B will be described in some detail. It covers proton energies from 80 keV to 6 MeV, electrons from 20 keV to 2 MeV, and positrons from 150 to 550 keV. Its flight performance will be discussed. From examples of measurements the capability of the instrument will be demonstrated. (orig.) [de

  4. Experimental energy-dependent nuclear spin distributions

    International Nuclear Information System (INIS)

    Egidy, T. von; Bucurescu, D.

    2009-01-01

    A new method is proposed to determine the energy-dependent spin distribution in experimental nuclear-level schemes. This method compares various experimental and calculated moments in the energy-spin plane to obtain the spin-cutoff parameter σ as a function of mass A and excitation energy using a total of 7202 levels with spin assignment in 227 nuclei between F and Cf. A simple formula, σ 2 =0.391 A 0.675 (E-0.5Pa ' ) 0.312 , is proposed up to about 10 MeV that is in very good agreement with experimental σ values and is applied to improve the systematics of level-density parameters.

  5. Medium energy nuclear physics research

    International Nuclear Information System (INIS)

    Peterson, G.A.; Dubach, J.F.; Hicks, R.S.; Miskimen, R.A.

    1988-09-01

    The UMass group has concentrated on using electromagnetic probes, particularly the electron in high-energy scattering experiments at the Stanford Liner Accelerator Center (SLAC). Plans are also being made for high energy work at the Continuous Beam Accelerator Facility (CEBAF). The properties of this accelerator should permit a whole new class of coincidence experiments to be carried out. At SLAC UMass has made major contributions toward the plans for a cluster-jet gas target and detector system at the 16 GeV PEP storage ring. For the future CEBAF accelerator, tests were made of the feasibility of operating wire drift chambers in the vicinity of a continuous electron beam at the University Illinois microtron. At the same time a program of studies of the nuclear structure of more complex nuclei has been continued at the MIT-Bates Linear Accelerator Center and in Amsterdam at the NIKHEF-K laboratory. At the MIT-Bates Accelerator, because of an unforeseen change in beam scheduling as a result of problems with the T 20 experiment, the UMass group was able to complete data acquisition on experiments involving 180 degrees elastic magnetic scattering on 117 Sn and 41 Ca. A considerable effort has been given to preparations for a future experiment at Bates involving the high-resolution threshold electrodisintegration of the deuteron. The use of these chambers should permit a high degree of discrimination against background events in the measurement of the almost neutrino-like small cross sections that are expected. In Amsterdam at the NIKHEF-K facility, single arm (e,e') measurements were made in November of 1987 on 10 B in order to better determine the p 3/2 wave function from the transition from the J pi = 3 + ground state to the O + excited state at 1.74 MeV. In 1988, (e,e'p) coincidence measurements on 10 B were completed. The objective was to obtain information on the p 3/2 wave function by another means

  6. Medium energy nuclear physics research

    International Nuclear Information System (INIS)

    Peterson, G.A.; Dubach, J.F.; Hicks, R.S.; Miskimen, R.A.

    1992-06-01

    This paper covers the following topics: Experiment 87-02: Threshold Electrodisintegration of the Deuteron at High Q 2 ; Measurement of the 5th Structure Function in Deuterium and 12 C; Single-Particle Densities of sd-Shell Nuclei; Experiment 84-28: Transverse Form Factors of 117 Sn; Experiment 82-11: Elastic Magnetic Electron Scattering from 13 C; Experiment 89-09: Measurement of the Elastic Magnetic Form Factor of 3 He at High Momentum Transfer; Experiment 89-15: Coincidence Measurement of the D(e,e'p) Cross-Section at Low Excitation Energy and High Momentum Transfer; Experiment 87-09: Measurement of the Quadrupole Contribution to the N → Δ Excitation; Experiment E-140: Measurement of the x-, Q 2 and A-Dependence of R = σ L /σ T ; PEP Beam-Gas Event Analysis: Physics with the SLAC TPC/2γ Detector; Drift Chamber Tests at Brookhaven National Laboratory; Experiment PR-89-031: Multi-nucleon Knockout Using the CLAS Detector; Electronics Design for the CLAS Region 1 Drift Chamber; Color Transparencies in the Electroproduction of Nucleon Resonances; and Experiment PR-89-015: Study of Coincidence Reactions in the Dip and Delta-Resonance Regions

  7. Medium energy nuclear physics research

    International Nuclear Information System (INIS)

    Peterson, G.A.; Dubach, J.F.; Hicks, R.S.; Miskimen, R.A.

    1991-06-01

    This report discusses research conducted on the following topics: transverse from factors of 117 Sn; elastic magnetic electron scattering from 13 C at Q 2 = 1 GeV 2 /c 2 ; a re-analysis of 13 C elastic scattering; deuteron threshold electrodisintegration; measurement of the elastic magnetic form factor of 3 He at high momentum transfer; coincidence measurement of the D(e,e'p) cross-section at low excitation energy and high momentum transfer; measurement of the quadrupole contribution to the N → Δ excitation; measurement of the x-, Q 2 -, and A-dependence of R = σ L /σ T ; the PEGASYS project; PEP beam-gas event analysis; plans for other experiments at SLAC: polarized electron scattering on polarized nuclei; experiment PR-89-015: study of coincidence reactions in the dip and delta-resonance regions; experiment PR-89-031: multi-nulceon knockout using the CLAS detector; drift chamber tests; a memorandum of understanding and test experiments; photoprotons from 10 B; and hadronic electroproduction at LEP

  8. High energy hadron spin-flip amplitude

    International Nuclear Information System (INIS)

    Selyugin, O.V.

    2016-01-01

    The high-energy part of the hadron spin-flip amplitude is examined in the framework of the new high-energy general structure (HEGS) model of the elastic hadron scattering at high energies. The different forms of the hadron spin-flip amplitude are compared in the impact parameter representation. It is shown that the existing experimental data of the proton-proton and proton-antiproton elastic scattering at high energy in the region of the diffraction minimum and at large momentum transfer give support in the presence of the energy-independent part of the hadron spin-flip amplitude with the momentum dependence proposed in the works by Galynskii-Kuraev. [ru

  9. The DHG sum rule measured with medium energy photons

    International Nuclear Information System (INIS)

    Hicks, K.; Ardashev, K.; Babusci, D.

    1997-01-01

    The structure of the nucleon has many important features that are yet to be uncovered. Of current interest is the nucleon spin-structure which can be measured by doing double-polarization experiments with photon beams of medium energies (0.1 to 2 GeV). One such experiment uses dispersion relations, applied to the Compton scattering amplitude, to relate measurement of the total reaction cross section integrated over the incident photon energy to the nucleon anomalous magnetic moment. At present, no single facility spans the entire range of photon energies necessary to test this sum rule. The Laser-Electron Gamma Source (LEGS) facility will measure the double-polarization observables at photon energies between 0.15--0.47 MeV. Either the SPring8 facility, the GRAAL facility (France), or Jefferson Laboratory could make similar measurements at higher photon energies. A high-precision measurement of the spin-polarizability and the Drell-Hearn-Gerasimov sum rule is now possible with the advent of high-polarization solid HD targets at medium energy polarized photon facilities such as LEGS, GRAAL and SPring8. Other facilities with lower polarization in either the photon beam or target (or both) are also pursuing these measurements because of the high priority associated with this physics. The Spin-asymmetry (SASY) detector that will be used at LEGS has been briefly outlined in this paper. The detector efficiencies have been explored with simulations studies using the GEANT software, with the result that both charged and uncharged pions can be detected with a reasonable efficiency (> 30%) over a large solid angle. Tracking with a TPC, which will be built at LEGS over the next few years, will improve the capabilities of these measurements

  10. The inelastic scattering of medium energy α particles

    International Nuclear Information System (INIS)

    Crut, M.

    1960-01-01

    The aim of this work is to find out what are the properties of the so-called 'anomalous states' in medium weight nuclei. These states preferentially excited in the inelastic scattering of medium energy charged particles have an excitation energy at about 4 MeV for nuclei with Z ≤ 29 and in the range 2-3 MeV for high Z nuclei. From a combination of angular distribution data in the elastic and inelastic scattering of 30 MeV α particles, and correlation data between inelastic α particles and deexcitation γ rays, we show that for even-even nuclei, we can attribute spin 3 and parity minus to these 'anomalous states'. This is quite in agreement with the interpretation of these levels suggested by Lane as due to collective octupole oscillations. We give a resume of the theories used in the analysis of the data and a description of the experimental set-up. (author) [fr

  11. Spin physics at intermediate energies

    International Nuclear Information System (INIS)

    Burkert, V.

    1986-01-01

    In this session a total of 25 contributed papers were presented studying a broad range of spin effects in nucleons and nuclei using electromagnetic (electrons and photons) and hadronic (pions and nucleons) probes. The status of the theory was characterized by its almost total absence. Only one theoretical contribution was presented at this session. Those experiments examining electromagnetic-, electroweak- and weak-strong interactions were emphasized

  12. Correlation functions of electronic and nuclear spins in a Heisenberg antiferromagnet semi-infinite medium

    International Nuclear Information System (INIS)

    Sarmento, E.F.

    1981-01-01

    Results are found for the dynamical correlation functions (or its corresponding Green's functions) among any combination including operator pairs of electronic and nuclear spins in an antiferromagnet semi-infinite medium, at low temperatures T [pt

  13. Spin-dependent relativistic effect on heavy quarkonium properties in medium

    International Nuclear Information System (INIS)

    Dong Yubing

    1997-01-01

    Spin-dependent relativistic effect on the binding and dissociation of the heavy quarkonium in a thermal environment is investigated. The result shows that the interactions could influence the heavy quarkonium properties in medium

  14. [Medium energy physics at Syracuse University: Technical progress report

    International Nuclear Information System (INIS)

    Souder, P.A.

    1986-01-01

    The primary focus of research has been an experiment at the MIT-Bates Linear Accelerator Center to measure the spin-dependence of elastic scattering of electrons from carbon. The Syracuse University Medium Energy Physics Group is also part of a collaboration which will measure the tensor polarization of deuterons scattered by electrons. Finally, analysis has been completed for an experiment at LAMPF in which the first observation of the exotic ion μ + e - e - was made. 17 refs., 18 figs., 2 tabs

  15. Spin structure in high energy processes: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    DePorcel, L.; Dunwoodie, C. [eds.

    1994-12-01

    This report contains papers as the following topics: Spin, Mass, and Symmetry; physics with polarized Z{sup 0}s; spin and precision electroweak physics; polarized electron sources; polarization phenomena in quantum chromodynamics; polarized lepton-nucleon scattering; polarized targets in high energy physics; spin dynamics in storage rings and linear accelerators; spin formalism and applications to new physics searches; precision electroweak physics at LEP; recent results on heavy flavor physics from LEP experiments using 1990--1992 data; precise measurement of the left-right cross section asymmetry in Z boson production by electron-positron collisions; preliminary results on heavy flavor physics at SLD; QCD tests with SLD and polarized beams; recent results from TRISTAN at KEK; recent B physics results from CLEO; searching for the H dibaryon at Brookhaven; recent results from the compton observatory; the spin structure of the deuteron; spin structure of the neutron ({sup 3}HE) and the Bjoerken sum rule; a consumer`s guide to lattice QCD results; top ten models constrained by b {yields} sy; a review of the Fermilab fixed target program; results from the D0 experiment; results from CDF at FNAL; quantum-mechanical suppression of bremsstrahlung; report from the ZEUS collaboration at HERA; physics from the first year of H1 at HERA, and hard diffraction. These papers have been cataloged separately elsewhere.

  16. Spin structure in high energy processes: Proceedings

    International Nuclear Information System (INIS)

    DePorcel, L.; Dunwoodie, C.

    1994-12-01

    This report contains papers as the following topics: Spin, Mass, and Symmetry; physics with polarized Z 0 s; spin and precision electroweak physics; polarized electron sources; polarization phenomena in quantum chromodynamics; polarized lepton-nucleon scattering; polarized targets in high energy physics; spin dynamics in storage rings and linear accelerators; spin formalism and applications to new physics searches; precision electroweak physics at LEP; recent results on heavy flavor physics from LEP experiments using 1990--1992 data; precise measurement of the left-right cross section asymmetry in Z boson production by electron-positron collisions; preliminary results on heavy flavor physics at SLD; QCD tests with SLD and polarized beams; recent results from TRISTAN at KEK; recent B physics results from CLEO; searching for the H dibaryon at Brookhaven; recent results from the compton observatory; the spin structure of the deuteron; spin structure of the neutron ( 3 HE) and the Bjoerken sum rule; a consumer's guide to lattice QCD results; top ten models constrained by b → sy; a review of the Fermilab fixed target program; results from the D0 experiment; results from CDF at FNAL; quantum-mechanical suppression of bremsstrahlung; report from the ZEUS collaboration at HERA; physics from the first year of H1 at HERA, and hard diffraction. These papers have been cataloged separately elsewhere

  17. Relativistic energy loss in a dispersive medium

    DEFF Research Database (Denmark)

    Houlrik, Jens Madsen

    2002-01-01

    The electron energy loss in a dispersive medium is obtained using macroscopic electrodynamics taking advantage of a static frame of reference. Relativistic corrections are described in terms of a dispersive Lorentz factor obtained by replacing the vacuum velocity c by the characteristic phase...... velocity c/n, where n is the complex index of refraction. The angle-resolved energy-loss spectrum of a Drude conductor is analyzed in detail and it is shown that the low-energy peak due to Ohmic losses is enhanced compared to the classical approximation....

  18. In-medium scaling law and electron scattering from high-spin states in 208Pb

    International Nuclear Information System (INIS)

    Arias de Saavedra, F.; Lallena, A.M.

    1994-01-01

    The effects of the environment modifications in the structure of the low-lying high-spin states of 208 Pb are studied by analyzing how the in-medium scaling law works on the excitation energies, wave functions, and electron scattering form factors corresponding to these states. It is shown that the consideration of f π * in addition to the effective ρ-meson mass does not affect too much most of the states analyzed. However, some of them appear to be extremely sensitive to its inclusion in the residual nucleon-nucleon interaction. As a result, a value of m ρ * /m ρ ∼f π * /f π ∼0.91 gives a good description of the (e,e') form factors of these particular states without any quenching factor. This value is in agreement with the one found for 48 Ca in a similar analysis performed in a previous work

  19. Innovative spin precessor for intermediate energy protons

    International Nuclear Information System (INIS)

    Hoffman, E.W.

    1979-01-01

    A spin precessor has been designed to provide arbitrary orientation of the polarization in the external proton beam at LAMPF. The device utilizes two superconducting solenoids, three conventional dipoles, and conversion of polarized H - to H + to provide an achromatic, undeflected beam with tunable spin orientation over a range of energies from 400 MeV to 800 MeV. A portion of this device is being installed to provide compatibility between two facilities which simultaneously use two branches of the external proton beam at LAMPF

  20. Medium-energy ion reflection from solids

    CERN Document Server

    Mashkova, ES

    1985-01-01

    ``Medium-Energy Ion Reflection from Solids'' analyses the results of experimental, theoretical and computer investigations on the process of scattering of ions by solid surfaces. Surface scattering is a relatively young and rapidly developing branch of the physics of atomic collisions and the literature on this subject has rapidly grown.As the first monograph devoted specifically to surface scattering of ions, this book is directed at scientists involved in ion-solid interaction studies.

  1. Medium energy probes and nuclear structure

    International Nuclear Information System (INIS)

    Ginocchio, J.N.

    1984-01-01

    In this paper we explore two topics. The first topic is the marriage of medium energy reaction theory with the interacting boson model of nuclei in such a way that the multiple scattering is summed to all orders. The second topic is an exactly solvable potential model which gives realistic shell model eigenfunctions which can be used to calculate static and transition nuclear densities. (orig./HSI)

  2. A medium energy neutron deep penetration experiment

    International Nuclear Information System (INIS)

    Amian, W.; Cloth, P.; Druecke, V.; Filges, D.; Paul, N.; Schaal, H.

    1986-11-01

    A deep penetration experiment conducted at the Los Alamos WNR facility's Spallation Neutron Target is compared with calculations using intra-nuclear-cascade and S N -transport codes installed at KFA-IRE. In the experiment medium energy reactions induced by neutrons between 15 MeV and about 150 MeV inside a quasi infinite slab of iron have been measured using copper foil monitors. Details of the experimental procedure and the theoretical methods are described. A comparison of absolute reaction rates for both experimentally and theoretically derived reactions is given. The present knowledge of the corresponding monitor reaction cross sections is discussed. (orig.)

  3. Medium energy hadron scattering from nuclei

    International Nuclear Information System (INIS)

    Ginocchio, J.N.; Wenes, G.

    1986-01-01

    The Glauber approximation for medium energy scattering of hadronic projectiles from nuclei is combined with the interacting boson model of nuclei to produce a transition matrix for elastic and inelastic scattering in algebraic form which includes coupling to all the intermediate states. We present closed form analytic expresions for the transition matrix elements for the three dynamical symmetries of the interacting boson model; that is for, a spherical quadrupole vibrator, a γ unstable rotor, and both prolate and oblate axially symmetric rotors. We give examples of application of this formalism to proton scattering from 154 Sm and 154 Gd. 27 refs., 5 figs., 1 tab

  4. Probing in-medium spin–orbit interaction with intermediate-energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Xu, Jun; Li, Bao-An

    2013-01-01

    Incorporating for the first time both the spin and isospin degrees of freedom explicitly in transport model simulations of intermediate-energy heavy-ion collisions, we observe that a local spin polarization appears during collision process. Most interestingly, it is found that the nucleon spin up–down differential transverse flow is a sensitive probe of the spin–orbit interaction, providing a novel approach to probe both the density and isospin dependence of the in-medium spin–orbit coupling that is important for understanding the structure of rare isotopes and synthesis of superheavy elements

  5. 16th Workshop on High Energy Spin Physics

    CERN Document Server

    2016-01-01

    The Workshop will cover a wide range of spin phenomena at high and intermediate energies such as: recent experimental data on spin physics the nucleon spin structure and GPD's spin physics and QCD spin physics in the Standard Model and beyond T-odd spin effects polarization and heavy ion physics spin in gravity and astrophysics the future spin physics facilities spin physics at NICA polarimeters for high energy polarized beams acceleration and storage of polarized beams the new polarization technology related subjects The Workshop will be held in the Bogoliubov Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, Russia. The program of the workshop will include plenary and parallel (if necessary) sessions. Plenary sessions will be held in the Conference Hall. Parallel sections will take place in the same building. There will be invited talks (up to 40 min) and original reports (20 min). The invited speakers will present new experimental and theoretical re...

  6. Centrifugal Spinning and Its Energy Storage Applications

    Science.gov (United States)

    Yao, Lu

    -/micro-fiber production method to substitute electrospinning in industrial production. Recently, centrifugal spinning has gained researchers' attention. The centrifugal spinning method avoids the use of high voltage supply and can work with concentrated solutions, and most importantly, it can increase the production rate of nano-/micro-fibers to at least two orders or magnitude higher than that of electrospinning. This novel fiber fabrication approach is mostly used in tissue engineering field, and it can be potentially applied in preparing electrodes for SIBs and EDLCs. In the present work, we firstly study the influence of solution intrinsic properties and operational parameters using polyacrylonitrile as an example, and establish the processing-structure relationships for this spinning technique. We then use this novel spinning method to prepare porous carbon nanofibers (PCNFs), SnO2 microfibers and lithium-substituted sodium layered transition metal oxide fibers and use them as electrodes for EDLCs and SIBs. The as-prepared PCNFs, SnO2 microfibers and lithiumsubstituted sodium layered transition metal oxide fibers exhibit good electrochemical performance. It is therefore demonstrated that centrifugal spinning can be a promising nano- /micro-fiber preparation approach for mass production of electrode materials used in energy storage applications.

  7. [Medium high energy physics at Syracuse University

    International Nuclear Information System (INIS)

    Souder, P.A.

    1991-10-01

    This report discusses: Polarized muonic atoms; spin-dependent structure functions of the neutron; parity violation in the scattering of polarized electrons; tensor polarization in elastic eD scattering; and, hyperfine structure of muonium

  8. Spin effects in high energy quark-quark scattering

    International Nuclear Information System (INIS)

    Goloskokov, S.V.; Selyugin, O.V.

    1993-01-01

    The spin amplitudes in high-energy quark-quark scattering at /t/>1 GeV 2 are analyzed. It is shown that the gluon contributions in the QCDα s 3 order lead to the spin-flip amplitude growing as s. This means the existence of the spin-flip part in pomeron exchange. The resulting T f is about few per cent of the spin-non-flip contribution. The factorization of the large-distance and high-energy effects in the spin-flip amplitude is obtained. 13 refs.; 2 figs.; 1 tab

  9. Low energy spin excitations in chromium metal

    International Nuclear Information System (INIS)

    Pynn, R.; Azuah, R.T.; Stirling, W.G.

    1997-01-01

    Neutron scattering experiments with full polarization analysis have been performed with a single crystal of chromium to study the low-energy spin fluctuations in the transverse spin density wave (TSDW) state. A number of remarkable results have been found. Inelastic scattering observed close to the TSDW satellite positions at (1 ± δ,0,0) does not behave as expected for magnon scattering. In particular, the scattering corresponds to almost equally strong magnetization fluctuations both parallel and perpendicular to the ordered moments of the TSDW phase. As the Neel temperature is approached from below, scattering at the commensurate wavevector (1,0,0) increases in intensity as a result of critical scattering at silent satellites (1,0, ± δ) being included within the spectrometer resolution function. This effect, first observed by Sternlieb et al, does not account for all of the inelastic scattering around the (1,0,0) position, however, Rather, there are further collective excitations, apparently emanating from the TSDW satellites, which correspond to magnetic fluctuations parallel to the ordered TSDW moments. These branches have a group velocity that is close to that of (1,0,0) longitudinal acoustic (LA) phonons, but assigning their origin to magneto-elastic scattering raises other unanswered questions

  10. Signature for g bosons from medium energy proton scattering experiments

    International Nuclear Information System (INIS)

    Kuyucak, S.

    1993-01-01

    We apply the recently developed algebraic (1/N expansion) scattering formalism to medium energy proton scattering from 154 Sm and 176 Yb. The nuclear structure effects in this formalism are described by the interacting boson model generalized to arbitrary interactions and types of bosons i.e. s,d,g, etc. We find that, in the sd boson model, a consistent description of cross sections is possible only for the 0 + and 2 + states. The failure of the model with regard to the 4 + states indicates that the effective hexadecapole operator used in the sd model is inadequate. In contrast, the data for scattering to the 0 + , 2 + and 4 + states could be consistently described in the sdg boson model. The spectroscopic data for the low-lying levels usually can not distinguish between the sd and sdg models due to renormalization of parameters, and one has to look at high spin or energy data for evidence of g bosons. The inelastic proton scattering experiments, on the other hand, directly probe the wave functions, and hence could provide a signature for g bosons even in the ground band states

  11. Development of the Medium Energy Linac Systems

    International Nuclear Information System (INIS)

    Jang, Ji Ho; Kwon, Hyeok Jung; Kim, Dae Il; Kim, Han Sung; Park, Bum Sik; Seol, Kyung Tae; Song, Young Gi; Yun, Sang Pil; Cho, Yong Sub; Hong, In Seok

    2008-05-01

    The main purpose of this project is developing 100-MeV proton linear accelerator (linac) for proton engineering frontier project (PEFP). In the first phase of the PEFP, the development of the 20-MeV linac has successfully finished. Hence the work scope of this project is designing the linac to accelerate proton beams from 20-MeV up to 100-MeV, fabricating the linac up to 45 MeV, fabricating one set of the medium energy beam transport (MEBT) tank, and developing the low level radio frequency (LLRF) system and the control system. The basic role of the new proton accelerator is accelerating 20-mA proton beams from 20 MeV up to 100 MeV. The first step of the design procedure is optimizing and determining the accelerator parameters. The beam loss is also main concern in the design stage. The drift tube (DT) and the quadrupole magnets are designed to be optimized to the new linac design. The other purpose is confirming the new design by fabricating and tuning the drift tube linac (DTL). The 20MeV proton beam divided into two directions. One is supplying the beams to user group by turning on the 45-degree bending magnet. The other is guided into the 100-MeV DTL by tuning off the dipole magnet. That is why the PEFP MEBT located after 20-MeV DTL. The MEBT is realized as two small DTL tanks with three cells and a 45-degree bending magnet. The fabrication of one MEBT tank is another purpose of this project. The other purposes of this project is developing the LLRF system to control the RF signal and control system to monitor and control the vacuum system, magnet power supply, etc

  12. Theoretical studies in medium-energy nuclear and hadronic physics

    International Nuclear Information System (INIS)

    Horowitz, C.J.; Macfarlane, M.H.; Matsui, T.; Serot, B.D.

    1993-01-01

    A proposal for theoretical nuclear physics research is made for the period April 1, 1993 through March 31, 1996. Research is proposed in the following areas: relativistic many-body theory of nuclei and nuclear matter, quasifree electroweak scattering and strange quarks in nuclei, dynamical effects in (e,e'p) scattering at large momentum transfer, investigating the nucleon's parton sea with polarized leptoproduction, physics of ultrarelativistic nucleus endash nucleus collisions, QCD sum rules and hadronic properties, non-relativistic models of nuclear reactions, and spin and color correlations in a quark-exchange model of nuclear matter. Highlights of recent research, vitae of principal investigators, and lists of publications and invited talks are also given. Recent research dealt primarily with medium-energy nuclear physics, relativistic theories of nuclei and the nuclear response, the nuclear equation of state under extreme conditions, the dynamics of the quark endash gluon plasma in relativistic heavy-ion collisions, and theories of the nucleon endash nucleon force

  13. Medium properties and total energy coupling in underground explosions

    International Nuclear Information System (INIS)

    Kurtz, S.R.

    1975-01-01

    A phenomenological model is presented that allows the direct calculation of the effects of variations in medium properties on the total energy coupling between the medium and an underground explosion. The model presented is based upon the assumption that the shock wave generated in the medium can be described as a spherical blast wave at early times. The total energy coupled to the medium is then simply the sum of the kinetic and internal energies of this blast wave. Results obtained by use of this model indicate that the energy coupling is more strongly affected by the medium's porosity than by its water content. These results agree well with those obtained by summing the energy deposited by the blast wave as a function of range

  14. Inelastic proton scattering at medium energy

    International Nuclear Information System (INIS)

    Love, W.G.

    1980-01-01

    Some of the most essential characteristics of the nucleon-nucleon interaction for probing nuclear structure at bombarding energies between 100 and 800 MeV are considered. With a local representation of the on-shell N-N t-matrix, data for a variety of specific transitions at IUCF and LAMPF energies are discussed with an emphasis on the nuclear structure information sampled by proton scattering. The importance of incorporating constraints on nuclear structure imposed by electron scattering is stressed. Some rather unique aspects of the (p,n) reaction at intermediate energies are discussed in terms of its energy dependence and nuclear structure sum rules. 11 figures

  15. Energy efficient hybrid computing systems using spin devices

    Science.gov (United States)

    Sharad, Mrigank

    Emerging spin-devices like magnetic tunnel junctions (MTJ's), spin-valves and domain wall magnets (DWM) have opened new avenues for spin-based logic design. This work explored potential computing applications which can exploit such devices for higher energy-efficiency and performance. The proposed applications involve hybrid design schemes, where charge-based devices supplement the spin-devices, to gain large benefits at the system level. As an example, lateral spin valves (LSV) involve switching of nanomagnets using spin-polarized current injection through a metallic channel such as Cu. Such spin-torque based devices possess several interesting properties that can be exploited for ultra-low power computation. Analog characteristic of spin current facilitate non-Boolean computation like majority evaluation that can be used to model a neuron. The magneto-metallic neurons can operate at ultra-low terminal voltage of ˜20mV, thereby resulting in small computation power. Moreover, since nano-magnets inherently act as memory elements, these devices can facilitate integration of logic and memory in interesting ways. The spin based neurons can be integrated with CMOS and other emerging devices leading to different classes of neuromorphic/non-Von-Neumann architectures. The spin-based designs involve `mixed-mode' processing and hence can provide very compact and ultra-low energy solutions for complex computation blocks, both digital as well as analog. Such low-power, hybrid designs can be suitable for various data processing applications like cognitive computing, associative memory, and currentmode on-chip global interconnects. Simulation results for these applications based on device-circuit co-simulation framework predict more than ˜100x improvement in computation energy as compared to state of the art CMOS design, for optimal spin-device parameters.

  16. Joint energy and spinning reserve dispatching and pricing

    International Nuclear Information System (INIS)

    Rashidinejad, M.; Song, Y.-H.; Javidi Dasht-Bayaz, M.H.

    2000-01-01

    Unpredictable load demand variations, and also sudden generation interruption, may cause imbalance in power systems. To prevent any blackout and to reduce such total power imbalance, spinning reserve can provide electric power system ability to respond. Adequate amount of spinning reserve should be based on economy and risk as an optimal decision making. This paper uses Quadratic Programming (QP) method to solve Joint Energy and Spinning Reserve Dispatch (JESRD) problem and derives the optimal price of spinning reserve. In JESRD, Unserved Energy Cost (UEC) is considered as an Opportunity Cost of Spinning Reserve (OCSR). To distribute the System Reserve Requirements (SRR) among generation units, two different models, Fixed Reserve Percentage (FRP) or fixed allocation model and Non-Fixed Reserve Percentage (NFRP) or flexible allocation model has been investigated. Numerical results on a 5-bus test system and the 30-bus IEEE standard system, considering FRP and NFRP models are included. (author)

  17. Bounds on the maximum attainable equilibrium spin polarization of protons at high energy in HERA

    International Nuclear Information System (INIS)

    Vogt, M.

    2000-12-01

    For some years HERA has been supplying longitudinally spin polarised electron and positron (e ± ) beams to the HERMES experiment and in the future longitudinal polarisation will be supplied to the II1 and ZEUS experiments. As a result there has been a development of interest in complementing the polarised e ± beams with polarised protons. In contrast to the case of e ± where spin flip due to synchrotron radiation in the main bending dipoles leads to self polarisation owing to an up-down asymmetry in the spin flip rates (Sokolov-Ternov effect), there is no convincing self polarisation mechanism for protons at high energy. Therefore protons must be polarised almost at rest in a source and then accelerated to the working energy. At HERA, if no special measures are adopted, this means that the spins must cross several thousand ''spin-orbit resonances''. Resonance crossing can lead to loss of polarisation and at high energy such effects are potentially strong since spin precession is very pronounced in the very large magnetic fields needed to contain the proton beam in HERA-p. Moreover simple models which have been successfully used to describe spin motion at low and medium energies are no longer adequate. Instead, careful numerical spin-orbit tracking simulations are needed and a new, mathematically rigorous look at the theoretical concepts is required. This thesis describes the underlying theoretical concepts, the computational tools (SPRINT) and the results of such a study. In particular strong emphasis is put on the concept of the invariant spin field and its non-perturbative construction. The invariant spin field is then used to define the amplitude dependent spin tune and to obtain numerical non-perturbative estimates of the latter. By means of these two key concepts the nature of higher order resonances in the presence of snakes is clarified and their impact on the beam polarisation is analysed. We then go on to discuss the special aspects of the HERA-p ring

  18. Double photoionization of lithium at medium energies

    International Nuclear Information System (INIS)

    Wehlitz, R.; Bluett, J.B.; Martinez, M.M.; Lukic, D.; Whitfield, S.B.

    2004-01-01

    Full text: The double-to-single photoionization ratio of atomic lithium has been measured for photon energies ranging from 120 eV to 910 eV . Through the extensive use of various filters we were able to significantly extend the previous range of measurements. We d that our data are in agreement with the predicted high-energy limit of 3.4%. By applying simple model curves to our data, we attempt to disentangle the different processes leading to a doubly charged Li ion. Our model corroborates the notion that sequential processes contribute substantially to the double-photoionization cross-section ratio as predicted by theory. This work was supported by NSF under Grant No. PHY-9987638. The SRC is supported by NSF Grant No. DMR-0084402. M.M.M. acknowledges financial support through the NSF REU program

  19. Photoproduction of scalar mesons at medium energies

    Energy Technology Data Exchange (ETDEWEB)

    Da Silva, M. L. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-090, Pelotas, RS (Brazil); Machado, M. V. [High Energy Physics Phenomenology Group, GFPAE IF-UFRGS, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS (Brazil)

    2013-03-25

    In this work we will focus on photoproduction of mesons states a{sub 0}(980), f{sub 0}(1500) and f{sub 0}(1710). The f{sub 0}(1500) and f{sub 0}(1710) mesons will be considered in distinct mixing possibilities and assuming that a{sub 0}(980) is member of the ground-state nonet. The theoretical formalism is the Regge approach with reggeized {rho} and {omega} exchange. The differential and integrated total cross section are computed for the cases of the mesons a{sub 0}(980), f{sub 0}(1500) and f{sub 0}(1710) focusing the GlueX energy regime with photon energy E = 9 GeV.

  20. Experimental study of high spin states in low-medium mass nuclei by use of charge particle induced reactions

    International Nuclear Information System (INIS)

    Alenius, N.G.

    1975-01-01

    For the test of nuclear models the study of the properties of nuclear states of high angular momentum is especially important, because such states can often be given very simple theoretical descriptions. High spin states are easily populated by use of reactions initiated by alpha particles or heavy ions. In this thesis a number of low-medium mass nuclei have been studied, with emphasis on high spin states. (Auth.)

  1. Medium Energy Particle Physics - Muonium/RHIC - SPIN

    International Nuclear Information System (INIS)

    Hughes, V. W.

    2003-01-01

    This grant enabled research from 1991 to 2001 on muonium, the bound state of a positive muon and electron. The effort was led by Vernon Hughes, and involved almost 20 physicists from four U.S. and two international institutions. The experiment E1054 performed under the grant at the Clinton P. Anderson Meson Physics Facility at Los Alamos, was both a continuation and improvement on a series of experiments dating back to the discovery of muonium in 1960. High precision measurements of two Zeeman hyperfine transitions in the ground state of muonium were made, using microwave magnetic resonance spectroscopy and a line-narrowing technique. The experiment yielded the most precise values for the ground state hyperfine interval, Δv, to 12 ppb, and the ratio of muon to proton magnetic moments, μ μ /μ p to 120 ppb, representing a threefold (statistics limited) improvement over previous work. The mass of the muon, m μ , is also determined most precisely from this work. Comparison between theory and experiment for Δv constitutes the most precise test of bound-state QED, and also tests μe universality. Using the theoretical predictions for Δv, a value of the fine structure constant α was derived to 58 ppb. Finally, by searching for sidereal variations in the transition frequencies, limits were placed on the muon parameters of theoretical extensions of the standard model allowing CPT and Lorentz violation

  2. Spin observables in proton-neutron scattering at intermediate energy

    International Nuclear Information System (INIS)

    Spinka, H.

    1986-05-01

    A summary of np elastic scattering spin measurements at intermediate energy is given. Preliminary results from a LAMPF experiment to measure free neutron-proton elastic scattering spin-spin correlation parameters are presented. A longitudinally polarized proton target was used. These measurements are part of a program to determine the neutron-proton amplitudes in a model independent fashion at 500, 650, and 800 MeV. Some new proton-proton total cross sections in pure helicity states (Δσ/sub L/(pp)) near 3 GeV/c are also given. 37 refs., 2 figs

  3. Strong interactions studies with medium energy probes

    International Nuclear Information System (INIS)

    Seth, K.K.

    1993-10-01

    This progress report refers to the period August 1992 to August 1993, which includes the first year of the three-year period December 1, 1992--November 30, 1995 of the existing research contract. As anticipated in the 1992--1995 proposal the major preoccupation during 1992--1993 was with Fermilab experiment E760. This experiment, whose primary objective is to make very high-resolution study of Charmonium Spectroscopy via proton-antiproton annihilations, has turned out to be a veritable gold-mine of exciting hadronic physics in other areas as well. These include the proton from factor in the time-life region, proton-antiproton forward scattering, QCD scaling laws, and light quark spectroscopy. A large fraction of the data from E760 have been analyzed during this year, and several papers have been published. In addition to the E760 experiment at Fermilab continued progress was made earlier nuclear physics-related experiments at LAMPF, MIT, and NIKHEF, and their results for publication. Topics include high- resolution electron scattering, quasi-free electron scattering and low-energy pion double charge exchange

  4. Scattering amplitude and shift in self-energy in medium

    International Nuclear Information System (INIS)

    Mallik, S.

    2002-01-01

    Two simple proofs are presented for the first order virial expansion of the self-energy of a particle moving through a medium, characterised by temperature and/or chemical potential(s). One is based on the virial expansion of the self-energy operator itself, while the other is based on the analysis of its Feynman diagrams in configuration space. (orig.)

  5. Medium Access Control in Energy Harvesting - Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon

    Focusing on Wireless Sensor Networks (WSN) that are powered by energy harvesting, this dissertation focuses on energy-efficient communication links between senders and receivers that are alternating between active and sleeping states of operation. In particular, the focus lies on Medium Access...

  6. Spin asymmetries for elastic scattering in krypton at intermediate energies

    International Nuclear Information System (INIS)

    Went, M R; McEachran, R P; Lohmann, Birgit; MacGillivray, W R

    2002-01-01

    Measurements of the spin asymmetry for elastic scattering of spin-polarized electrons from krypton are presented, for incident energies in the range 20-200 eV. The measured spin asymmetries are generally small, and do not exceed 0.25 in magnitude at any energy or angle. The experimental results are compared with calculated values of the Sherman function, obtained by solution of the Dirac-Fock equations. The calculations have been performed with the inclusion of polarization and dynamic distortion potentials, and with the addition of an absorption potential to model inelastic processes. For incident energies of 50, 60 and 65 eV, the calculated values of the Sherman function are shown to be extremely sensitive to the details of the model, with the addition of the absorption potential producing dramatically different results

  7. Precompound decay models for medium energy nuclear reactions

    International Nuclear Information System (INIS)

    Blann, M.

    1989-11-01

    The formulations used for precompound decay models are presented and explained in terms of the physics of the intranuclear cascade model. Several features of spectra of medium energy (10--1000 MeV) reactions are summarized. Results of precompound plus evaporation calculations from the code ALICE are compared with a wide body of proton, alpha, and heavy ion induced reaction data to illustrate both the power and deficiencies of predicting yield of these reactions in the medium energy regime. 23 refs., 13 figs

  8. Significance of high energy spin effects in constituent pictures

    International Nuclear Information System (INIS)

    Chen, C.K.

    1977-01-01

    The spin information about high energy hadronic reactions is important for further understanding of the nature and the behavior of hadronic constituents. The usefulness of the information is discussed in the cases of dilepton production from hadronic collisions, large P/sub T/ inclusive and elastic scatterings, and small angle elastic scattering and quantum number exchanged reactions

  9. SLAC workshop on high energy electroproduction and spin physics

    International Nuclear Information System (INIS)

    1992-01-01

    These Proceedings contain copies of the transparencies presented at the Workshop on High Energy Electroproduction and Spin Physics held at SLAC on February 5--8, 1992. The purpose of this Workshop was to bring people together to discuss the possibilities for new experiments using the SLAC high intensity electron and photon beams and the facilities of End Station A

  10. El strength function at high spin and excitation energy

    International Nuclear Information System (INIS)

    Barrette, J.

    1983-04-01

    Recently giant dipole resonance-like concentration of the dipole strength function in nuclei was observed at both high excitation energies and high spins. This observation raises the possibility of obtaining new information on the shape of rapidly rotating heated nuclei. Recent experimental results on this subject are reviewed

  11. High energy spin waves in iron measured by neutron scattering

    International Nuclear Information System (INIS)

    Boothroyd, A.T.; Paul, D.M.; Mook, H.A.

    1991-01-01

    We present new results for the spin were dispersion relation measured along the [ζζ0] direction in bcc iron (12% silicon) by time-of-flight, neutron inelastic scattering. The excitations were followed to the zone boundary, where they are spread over a range of energies around 300meV. 6 refs., 2 figs

  12. In-medium effects around the Fermi energy

    Directory of Open Access Journals (Sweden)

    Lopez O.

    2015-01-01

    Full Text Available We study nuclear stopping in central collisions for heavy-ion induced reactions in the Fermi energy domain (15-100 AMeV. Using the large dataset provided by the 4π array INDRA, we determine that stopping can be directly related to the transport properties in the nuclear medium. By looking specifically at protons, we present a comprehensive body of experimental results concerning the mean free path, the nucleon-nucleon cross-section and in-medium effects in nuclear matter.

  13. Quantum mechanical equations of particle and spin motion in polarised medium

    International Nuclear Information System (INIS)

    Silenko, A.Ya.

    2003-01-01

    The quantum mechanical equations for the particles and spin motion in the media with polarized electrons by presence of the external fields are determined. The motion of the electrons and their spin are influenced by the exchange interaction whereas the motion of the positrons is the annihilation one. The second order summands by spin are accounted for the particles with the S≥1 spin. The obtained equations may applied for describing the particles and spin motion both in the magnetic and nonmagnetic media [ru

  14. Medium-energy charged-particle data for evaluation

    International Nuclear Information System (INIS)

    Pearlstein, S.

    1989-01-01

    Medium-energy charged particles incident on targets can cause a variety of nuclear reactions. Charged-particle transport calculations require access to a large body of cross-section data, which results in interest in an evaluated charged-particle data library. Developing an evaluated data library can involve several steps. An index to the literature on measurements and theory is useful to locate information relevant to data evaluation. A computerized compilation of measurements facilitates the intercomparison of different experiments and the determination of how well data are known. Nuclear models, based on theory or phenomenological evidence, are compared with experiment and, where validated, are used to fill in regions where experimental data are not available. Finally, the selected data are placed into computer-readable formats for use in transport calculations. Specialized indexes to bibliography help the scientist to keep up with his field and catch up with new subjects of interest. Several indexes are relevant to medium-energy nuclear data. In addition, these data are covered in several reports not issued on a regular basis. The technical area of medium-energy charged-particle data is maturing. From isolated measurements and theories, a comprehensive approach toward establishing a validated data base extending from low to high energies is emerging

  15. Development of a medium energy polarized neutron facility

    International Nuclear Information System (INIS)

    Burzynski, S.; Gysin, C.; Henneck, R.; Jourdan, J.; Kohler, D.; Pickar, M.A.; Plattner, G.R.; Sick, I.; Berdoz, A.; Foroughi, F.; Nussbaum, Ch.; Stammbach, Th.

    1984-01-01

    By the end of 1983 the major construction work for the new polarized neutron source was completed. The source will provide an essentially monoenergetic beam of both polarized and unpolarized neutrons in the energy range from 20 MeV to 70 MeV. Intensities are expected to be approx. 2 x 10 5 neutrons/s.cm 2 per μA of incident proton beam. The polarization is expected to be approx. 0.2 and can be chosen to be either longitudinal or transverse. Protons from the Philips injector cyclotron are focussed onto a liquid deuterium target and produce neutrons via the 2 H(p,n)2p reaction at 0 0 . This process provides essentially monoenergetic neutrons of almost the same energy as the incoming protons. The zero production angle implies that the neutron polarization comes from the polarization of the proton beam only. This allows an easy and fast change of the neutron spin direction by selecting proton spin states in the polarized ion source (atomic beam type). (Auth.)

  16. Light Spins of Cylindrical Electromagnetic Waves and their Jumps across Material Interfaces in the Presence of Energy Exchange

    Directory of Open Access Journals (Sweden)

    J. Mok

    2016-08-01

    Full Text Available We investigate light spins for cylindrical electromagnetic waves on resonance. To this goal, we consider both a dielectric cylinder of infinite length immersed in vacuum and a cylindrical hole punched through a dense dielectric medium. In order for waves of constant frequencies to be established through lossless media, energy absorption is allowed in the surrounding medium to compensate for radiation loss. The dispersion relation is then numerically solved for an asymmetry parameter implying a balance in energy exchange. Numerical studies are performed by varying parameters of refractive index contrast, azimuthal mode index, and size parameter of a cylindrical object. The resulting data is presented mostly in terms of a specific spin, defined as light spin per energy density. This specific spin is found to be bounded in its magnitude, with its maximum associated with either optical vortices or large rotations. Depending on parametric combinations, the specific spin could not only undergo finite jumps across the material interface but also exhibit limit behaviors.

  17. Relationship between energy landscape and low-temperature dynamics of ±J spin glasses

    International Nuclear Information System (INIS)

    Kobe, S.; Krawczyk, J.

    2004-01-01

    Clusters and valleys in the exact low-energy landscape of finite Edwards-Anderson ±J spin glasses are related to the distribution of spin domains and free spins in the ground states. The time evolution of the spin correlation function reflects a walk through the landscape at a given temperature and shows typical glassy behaviour

  18. Modeling the neutron spin-flip process in a time-of-flight spin-resonance energy filter

    CERN Document Server

    Parizzi, A A; Klose, F

    2002-01-01

    A computer program for modeling the neutron spin-flip process in a novel time-of-flight (TOF) spin-resonance energy filter has been developed. The software allows studying the applicability of the device in various areas of spallation neutron scattering instrumentation, for example as a dynamic TOF monochromator. The program uses a quantum-mechanical approach to calculate the local spin-dependent spectra and is essential for optimizing the magnetic field profiles along the resonator axis. (orig.)

  19. Free neutron-proton analyzing power at medium energies

    International Nuclear Information System (INIS)

    Newsom, C.R.

    1980-01-01

    In recent years, increasing efforts have been made to measure the nucleon-nucleon polarization parameters. To date, no free neutron-proton spin correlated parameters have been published in the energy range 500 to 800 MeV. Existing analyzing power data is of low precision and in most cases was obtained by quasi-free proton scattering. As a first step in determining the neutron-proton scattering matrix, the free neutron-proton analyzing power has been measured at the Los Alamos Physics Facility as a function of energy and angle. The experiment was performed by scattering a neutron beam from a polarized proton target. The neutron beam was generated by scattering 800 MeV protons from a Beryllium target and using the neutrons produced at 0 degrees. The incident energy ranged from 300 MeV to 800 MeV. The energy spread of the neutron beam made it possible to measure the analyzing power at different energies simultaneously. Angular distributions were taken from 60 to 170 degrees in the center of mass system (c.m.)

  20. Thermodynamical inequivalence of quantum stress-energy and spin tensors

    International Nuclear Information System (INIS)

    Becattini, F.; Tinti, L.

    2011-01-01

    It is shown that different couples of stress-energy and spin tensors of quantum-relativistic fields, which would be otherwise equivalent, are in fact inequivalent if the second law of thermodynamics is taken into account. The proof of the inequivalence is based on the analysis of a macroscopic system at full thermodynamical equilibrium with a macroscopic total angular momentum and a specific instance is given for the free Dirac field, for which we show that the canonical and Belinfante stress-energy tensors are not equivalent. For this particular case, we show that the difference between the predicted angular momentum densities for a rotating system at full thermodynamical equilibrium is a quantum effect, persisting in the nonrelativistic limit, corresponding to a polarization of particles of the order of (ℎ/2π)ω/KT (ω being the angular velocity) and could in principle be measured experimentally. This result implies that specific stress-energy and spin tensors are physically meaningful even in the absence of gravitational coupling and raises the issue of finding the thermodynamically right (or the right class of) tensors. We argue that the maximization of the thermodynamic potential theoretically allows us to discriminate between two different couples, yet for the present we are unable to provide a theoretical method to single out the best couple of tensors in a given quantum field theory. The existence of a nonvanishing spin tensor would have major consequences in hydrodynamics, gravity and cosmology.

  1. The inelastic scattering of medium energy {alpha} particles; Sur la diffusion inelastique des particules {alpha} a moyenne energie

    Energy Technology Data Exchange (ETDEWEB)

    Crut, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1960-07-01

    The aim of this work is to find out what are the properties of the so-called 'anomalous states' in medium weight nuclei. These states preferentially excited in the inelastic scattering of medium energy charged particles have an excitation energy at about 4 MeV for nuclei with Z {<=} 29 and in the range 2-3 MeV for high Z nuclei. From a combination of angular distribution data in the elastic and inelastic scattering of 30 MeV {alpha} particles, and correlation data between inelastic {alpha} particles and deexcitation {gamma} rays, we show that for even-even nuclei, we can attribute spin 3 and parity minus to these 'anomalous states'. This is quite in agreement with the interpretation of these levels suggested by Lane as due to collective octupole oscillations. We give a resume of the theories used in the analysis of the data and a description of the experimental set-up. (author) [French] Le but de cette etude est de determiner les proprietes des niveaux dits 'anormalement excites' lors de la diffusion inelastique des particules chargees de moyenne energie sur des noyaux de masse moyenne et lourde. L'energie de ces niveaux est de l'ordre de 4 MeV pour les noyaux avec Z {<=} 29 et de 2 a 3 MeV pour les noyaux de Z plus eleve. De l'examen des courbes de distribution angulaire des particules {alpha} de 30 MeV diffusees elastiquement et inelastiquement, et de la correlation angulaire entre {alpha} excitant ces niveaux 'anormaux' et {gamma} de desexcitation, on deduit que, dans le cas des pair-pair, on peut attribuer a ces niveaux spin 3 et parite moins. Ceci renforce l'hypothese emise par Lane qui attribue ces niveaux a des oscillations octupolaires de la surface du noyau. On donne un apercu des theories utilisees dans l'analyse des resultats et une description des dispositifs experimentaux. (auteur)

  2. Medium-Energy Nuclear Data Library (MENDLIB): Phase 1

    International Nuclear Information System (INIS)

    Siciliano, E.R.; Arthur, E.D.

    1987-10-01

    This document describes an initial step towards the formation of a computerized on-line data library, which would contain published medium-energy experimental data, and which would serve the basic and applied needs of the medium-energy nuclear physics community. The data emphasized in this project will be from measured charged-particle and meson induced nuclear scattering and reactions; an area for which no such data base presently exists. Access to the data will be through a menu-driven program in a user-friendly environment. The project is divided into three phases: Phase 1 involves compilation of Clinton P. Anderson Meson Physics Facility (LAMPF) data from nucleon and pion induced reactions, Phase 2 includes nucleon and pion data from other medium-energy facilities, and Phase 3 includes electron, light-ion, and possibly kaon and anti-nucleon data. The initial goals, the manner in which they would be pursued, and the resources needed to implement Phase 1 (the pilot phase) are discussed in detail. Possible expansion of Phase 1 to attain the envisioned goals of Phase 2 and 3 are briefly outlined. During all stages of the project, input from the community will be sought via the various facility user groups and the American Physical Society Division of Nuclear Physics. It is proposed that the Applied Nuclear Science Group (T-2) of the Los Alamos National Laboratory oversees the development and implementation of this project, and the LAMPF VAX computers be used as the host computers for on-line access

  3. Microscopic energy flows in disordered Ising spin systems

    International Nuclear Information System (INIS)

    Agliari, E; Casartelli, M; Vezzani, A

    2010-01-01

    An efficient microcanonical dynamics has been recently introduced for Ising spin models embedded in a generic connected graph even in the presence of disorder, i.e. with the spin couplings chosen from a random distribution. Such a dynamics allows a coherent definition of local temperatures also when open boundaries are coupled to thermostats, imposing an energy flow. Within this framework, here we introduce a consistent definition for local energy currents and we study their dependence on the disorder. In the linear response regime, when the global gradient between thermostats is small, we also define local conductivities following a Fourier discretized picture. Then, we work out a linearized 'mean-field approximation', where local conductivities are supposed to depend on local couplings and temperatures only. We compare the approximated currents with the exact results of the nonlinear system, showing the reliability range of the mean-field approach, which proves very good at high temperatures and not so efficient in the critical region. In the numerical studies we focus on the disordered cylinder but our results could be extended to an arbitrary, disordered spin model on generic discrete structures

  4. Theoretical interpretation of medium energy nucleon nucleus inelastic scattering

    International Nuclear Information System (INIS)

    Lagrange, Christian

    1970-06-01

    A theoretical study is made of the medium energy nucleon-nucleus inelastic scattering (direct interaction), by applying the distorted wave Born approximation such as can be deduced from the paired equation method. It is applied to the interpretation of the inelastic scattering of 12 MeV protons by 63 Cu; this leads us to make use of different sets of wave functions to describe the various states of the target nucleus. We analyze the nature of these states and the shape of the nucleon-nucleus interaction potential, and we compare the results with those obtained from other theoretical and experimental work. (author) [fr

  5. The nuclear spin response to intermediate energy protons and deuterons at low momentum transfer

    International Nuclear Information System (INIS)

    Baker, F.T.; Djalali, C.; Glashausser, C.; Lenske, H.; Love, W.G.; Tomasi-Gustafsson, E.; Wambach, J.

    1997-01-01

    Measurements of polarization transfer in the inelastic scattering of intermediate energy protons and deuterons have yielded a wealth of data on the spin response of nuclei. This work complements the well-known studies of Gamow-Teller strength in charge-exchange reactions. The emphasis here is on a consistent determination of the S=1, T=0 response, practical only with deuterons, and on the proper separation of S=0 and S=1 strength in proton spectra for appropriate comparison with sum rules. We concentrate on two nuclei, 40 Ca and 12 C, at momentum transfers below about 1 fm -1 and on excitations up to about 50 MeV. The continuum second random phase approximation provides the primary theoretical tool for calculating and interpreting the response in terms of properties of the nucleon-nucleon force inside the nuclear medium. The reaction mechanism is described by the DWIA, applied here to continuum proton scattering almost as rigorously as it is usually applied to low energy excitations. A new DWIA formalism for the description of spin observables in deuteron scattering is used. Comparison of the proton and deuteron data with each other and with RPA/DWIA calculations yields interesting insights into the current state of understanding of collectivity and the nuclear spin response. (orig.)

  6. Quantum dot as spin current generator and energy harvester

    Science.gov (United States)

    Szukiewicz, Barbara; Wysokiński, Karol I.

    2015-05-01

    The thermoelectric transport in the device composed of a central nanoscopic system in contact with two electrodes and subject to the external magnetic field of Zeeman type has been studied. The device can support pure spin current in the electrodes and may serve as a source of the temperature induced spin currents with possible applications in spintronics. The system may also be used as an energy harvester. We calculate its thermodynamic efficiency η and the power output P. The maximal efficiency of the device reaches the Carnot value when the device works reversibly but with the vanishing power. The interactions between carriers diminish the maximal efficiency of the device, which under the constant load drops well below the Carnot limit but may exceed the Curzon-Ahlborn limit. While the effect of intradot Coulomb repulsion on η depends on the parameters, the interdot/interlevel interaction strongly diminishes the device efficiency.

  7. Positronium-alkali atom scattering at medium energies

    International Nuclear Information System (INIS)

    Chakraborty, Ajoy; Basu, Arindam; Sarkar, Nirmal K; Sinha, Prabal K

    2004-01-01

    We investigate the scattering of orthopositronium (o-Ps) atom off different atomic alkali targets (Na to Cs) at low and medium energies (up to 120 eV). Projectile-elastic and target-elastic close-coupling models have been employed to investigate the systems in addition to the static-exchange model. Elastic, excitation and total cross sections have been reported for all four systems. The magnitude of the alkali excitation cross section increases with increasing atomic number of the target atom while the position of the peak value shifts towards lower incident energies. The magnitudes of the Ps excitation and ionization cross sections increase steadily with atomic number with no change in the peak position. The reported results show regular behaviour with increasing atomic number of the target atom. Scattering parameters for the Ps-Rb and Ps-Cs systems are being reported for the first time

  8. Injection system of teh SSC Medium Energy Booster

    International Nuclear Information System (INIS)

    Mao, N.; Gerig, R.; McGill, J.; Brown, K.

    1994-04-01

    The Medium Energy Booster (MEB) is the third of the SSCL accelerators and the largest of the resistive magnet synchrotrons. It accelerates protons from an injection momentum of 12 GeV/c to a top momentum of 200 GeV/c. A beam injection system has been designed to inject the beam transferred from the Low Energy Booster onto the MEB closed orbit in the MEB injection insertion region. The beam is injected via a vertical bending Lambertson septum magnet and a horizontal kicker with appropriate matching and very little beam loss and emittance dilution. The beam optics of the injection system is described in this paper. The required parameters of the Lambertson septum magnet and the injection kicker are given

  9. Medium energy measurements of N-N parameters. Progress in research, January 1, 1983-December 31, 1983

    International Nuclear Information System (INIS)

    1983-12-01

    The aim of the experimental program is the determination of the nucleon-nucleon amplitudes at medium energy. Experiments described include D/sub SS/, D/sub LS/, D/sub SL/, D/sub LL/, and P for p-p elastic scattering, the measurement of polarization observables in ppvector → pvector π + nu and ppvector → ppvector π, and measurements of the spin rotation parameters for pvector d → pvector d elastic scattering at 496, 647, and 800 MeV. Also, progress on an energy dependent proton-carbon analyzing power fit is reported. Current approved LAMPF proposals are described and 1983 publications are listed

  10. Electron spin polarization in high-energy storage rings

    International Nuclear Information System (INIS)

    Mane, S.R.

    1987-01-01

    In a high energy storage ring, a single photon emission has relatively little effect on the orbital motion, but it can produce a relatively large change in the electron spin state. Hence the unperturbed orbital motion can be satisfactorily described using classical mechanics, but the spin must be treated quantum mechanically. The electron motion is therefore treated semi-classically in this thesis. It is explained how to diagonalize the unperturbed Hamiltonian to the leading order in Planck's constant. The effects of perturbations are then included, and the relevant time-scales and ensemble averages are elucidated. The Derbenev-Kondratenko formula for the equilibrium degree of polarization is rederived. Mathematical details of the rederivation are given. Since the original authors used a different formalism, a proof is offered of the equivalence between their method and the one used in this thesis. An algorithm is also presented to evaluate the equilibrium polarization. It has a number of new features, which enable the polarization to be calculated to a higher degree of approximation than has hitherto been possible. This facilitates the calculation of so-called spin resonances, which are points at which the polarization almost vanishes. A computer program has been written to implement the above algorithm, in the approximation of linear orbital dynamics, and sample results are presented

  11. Summary of the 9th international symposium on high energy spin-physics

    International Nuclear Information System (INIS)

    Prescott, C.Y.

    1990-11-01

    Summarizing an international conference in high energy spin physics is never an easy task, because of the wide-ranging subjects in physics and technology that are involved. I have chosen to organize the topics of this conference into three broad categories relating to spin; intrinsic spin; composite spin; and spin, the experimental tool. In the first category, I will briefly revisit some historical and recent developments to set a background. In the second category, composite spin, I will discuss the status and developments in several areas, including magnetic moments of baryons, hyperon polarization in high energy high p perpendicular production, transverse polarization and asymmetries from transversely polarized targets in high p perpendicular scattering, spin structure of the proton, and the Bjorken sum rule. In the third category, I will discuss the steady, and at times rapid, progress in spin technology. In this part I include recent progress in high energy facilities, and comment on the highlights of the Workshops

  12. Muonium spin exchange in spin-polarized media: Spin-flip and -nonflip collisions

    International Nuclear Information System (INIS)

    Senba, M.

    1994-01-01

    The transverse relaxation of the muon spin in muonium due to electron spin exchange with a polarized spin-1/2 medium is investigated. Stochastic calculations, which assume that spin exchange is a Poisson process, are carried out for the case where the electron spin polarization of the medium is on the same axis as the applied field. Two precession signals of muonium observed in intermediate fields (B>30 G) are shown to have different relaxation rates which depend on the polarization of the medium. Furthermore, the precession frequencies are shifted by an amount which depends on the spin-nonflip rate. From the two relaxation rates and the frequency shift in intermediate fields, one can determine (i) the encounter rate of muonium and the paramagnetic species, (ii) the polarization of the medium, and most importantly (iii) the quantum-mechanical phase shift (and its sign) associated with the potential energy difference between electron singlet and triplet encounters. Effects of spin-nonflip collisions on spin dynamics are discussed for non-Poisson as well as Poisson processes. In unpolarized media, the time evolution of the muon spin in muonium is not influenced by spin-nonflip collisions, if the collision process is Poissonian. This seemingly obvious statement is not true anymore in non-Poissonian processes, i.e., it is necessary to specify both spin-flip and spin-nonflip rates to fully characterize spin dynamics

  13. A program in medium-energy nuclear physics

    International Nuclear Information System (INIS)

    Berman, B.L.; Dhuga, K.S.

    1992-01-01

    This report reviews progress on our nuclear-physics program for the last year, and includes as well copies of our publications and other reports for that time period. The structure of this report follows that of our 1991 Renewal Proposal and Progress Report: Sec. II outlines our research activities aimed at future experiments at CEBAF, NIKHEF, and Bates; Sec. III gives results of our recent research activities at NIKHEF, LAMPF, and elsewhere; Sec. IV provides an update of our laboratory activities at GWU, including the acquisition of our new Nuclear Detector Laboratory at our new Virginia Campus; and Sec. V is a list of our publications, proposals, and other reports. copies of those on medium-energy nuclear physics are reproduced in the Appendix

  14. Multiple scattering in the nuclear rearrangement reactions at medium energy

    International Nuclear Information System (INIS)

    Tekou, A.

    1980-09-01

    It is shown that the multiple scattering mechanism is very important in the transfer of the large momenta involved in the nuclear rearrangement reactions at medium energy. In contrast to the usual belief, the reaction cross-section is not very sensitive to the high momenta components of the nuclear wave function. The multiple scattering mechanism is especially important in 4 He(p,d) 3 He reaction around 800 MeV. Here the collisions involving two nucleons of the target nucleus are dominant. The triple collisions contribution is also important. The four collision contribution is negligible in the forward direction and sizeable at large angles. Thus, using the K.M.T. approach in DWBA calculations, the second order term of the optical potential must be included. So, is it not well established that the second term of the K.M.T. optical potential is important for the proton elastic scattering on light nuclei. (author)

  15. An intercomparison of medium energy cross-section codes

    International Nuclear Information System (INIS)

    Pearlstein, S.

    1988-05-01

    Five medium energy proton reaction cases are selected for benchmarking nuclear model codes. The quantities calculated are isotopic activation yields for 180 MeV protons on Al and 40-200 MeV protons on Co, and double differential neutron emission spectra from Al, Zr-90 and Pb-208 for 35, 80, 160, 318, and 800 presented consist of three types: a closed form preequilibrium plus evaporation model, an intranuclear-cascade and evaporation model, and a model relying on nuclear systematics. The characteristics of each code are described. There are orders of magnitude differences in the time for each type of code to calculate neutron emission spectra, with codes using systematics, preequilibrium and intranuclear-cascade models requiring seconds, minutes and hours, respectively. Calculations are not compared with experiment in this initial study. For double differential neutron emission spectra, there is good overall agreement in magnitude among the different types of codes at forward angles. Differences where they occur at forward angles are greatest for the mid-energy neutrons emitted. At back angles the incident energy at which the best overall agreement is obtained is 160 MeV and the material for which the best overall agreement is obtained is Al. 4 refs., 7 tabs

  16. Central Arkansas Energy Project. Coal to medium-Btu gas

    Science.gov (United States)

    1982-05-01

    The Central Arkansas Energy Project has as its objective the conversion of coal in a central location to a more readily usable energy source, medium Btu gas (MBG), for use at dispersed locations as fuel for power production and steam generation, or as a feedstock for chemical processing. The project elements consist of a gasification facility to produce MBG from coal, a pipeline to supply the MBG to the dispersed sites. The end of line users investigated were the repowering or refueling of an existing Arkansas Power and Light Co. Generating station, an ammonia plant, and a combined cycle cogeneration facility for the production of steam and electricity. Preliminary design of the gasification plant including process engineering design bases, process flow diagrams, utility requirements, system description, project engineering design, equipment specifications, plot plan and section plot plans, preliminary piping and instrument diagrams, and facilities requirements. Financial analyses and sensitivities are determined. Design and construction schedules and manpower loadings are developed. It is concluded that the project is technically feasible, but the financial soundness is difficult to project due to uncertainty in energy markets of competing fuels.

  17. Medium-spin levels and the character of the 20.4 ns 13/2+ isomer in 145Gd

    International Nuclear Information System (INIS)

    Pakkanen, A.; Muhonen, J.; Piiparinen, M.

    1981-06-01

    Levels of the N = 81 nucleus 145 Gd have been investigated by in-beam γ-ray and conversion electron spectroscopy with the 144 Sm( 3 He,2n) reaction. Fourteen new low- and medium-spin states between 1.0 and 2.4 MeV excitation, the known yrast levels up to spin (21/2) + , five other high-spin non-yrast states and a new 20.4 ns (13/2) + isomer at 2200.2 keV in 145 Gd have been observed. The isomer decays via a fast 927.3 keV E3 transition with B(E3) = 48 +- 7 W.u. Another weaker decay branch is a mixed, strongly hindered E1+M2+E3 transition to the νhsub(11/2)sup(-1) state. We propose an octupole νfsub(7/2)jsub(0)sup(-2)x3 - main configuration for the isomer, analogous to the 997 keV (13/2) + isomer in 147 Gd. The levels of 145 Gd are discussed on the basis of the spherical shell model. (author)

  18. Medium-Energy Particle experiments (MEPs) for the Exploration of energization and Radiation in Geospace (ERG) mission

    Science.gov (United States)

    Kasahara, S.; Yokota, S.; Mitani, T.; Asamura, K.; Hirahara, M.; Shibano, Y.; Yamamoto, K.; Takashima, T.

    2017-12-01

    ERG (Exploration of energization and Radiation in Geospace) is the geospace exploration spacecraft, which was launched on 20 December 2016. The mission goal is to unveil the physics behind the drastic radiation belt variability during space storms. One of key observations is the measurement of ions and electrons in the medium-energy range (10-200 keV), since these particles excite EMIC, magnetosonic, and whistler waves, which are theoretically suggested to play significant roles in the relativistic electron acceleration and loss. Medium-Energy Particle experiments - electron analyser (MEP-e) measures the energy and the direction of each incoming electron in the range of 7 to 87 keV. The sensor covers 2π radian disk-like field-of-view with 16 detectors, and the solid angle coverage is achieved by using spacecraft spin motion. The electron energy is independently measured by an electrostatic analyser and avalanche photodiodes, enabling the significant background reduction. Medium-Energy Particle experiments - ion mass analyzer (MEP-i) measures the energy, mass, and charge state of the direction of each incoming ion in the medium-energy range (180 keV/q). MEP-i thus provides the velocity distribution functions of medium-energy ions (e.g., protons and oxygens), from which we can obtain significant information on local ion energization and pitch angle scattering in the inner magnetosphere. Heavy ion measurements can also play an important role to restrict global mass transport including the ionosphere and the plasmasheet. Here we show the technical approaches, data output, and highlights of initial observations.

  19. Medium-spin states in the N=80 nuclei 139Pr and 141Pm

    International Nuclear Information System (INIS)

    Piiparinen, M.; Kortelahti, M.; Pakkanen, A.; Komppa, T.; Komu, R.

    1979-10-01

    The level structures of 139 Pr and 141 Pm have been investigated using (p,2n), ( 3 He,3n) and (α,4n) reactions and methods of in-beam γ-ray and electron spectroscopy. Fourteen new levels with spins up to (23 + /2) were observed in 139 Pr and seventeen new levels with spins up to 19 - /2 in 141 Pm. The level structures in both nuclei can be described by coupling the odd-proton intrinsic states to the excitations of the doubly even core. The ordering of the levels in the πhsub(11/2)x2 + multiplet is discussed on the basis of the triaxial rotor-plus-particle model calculations. The calculations suggest that a transition from a basically prolate to an oblate triaxial shape takes place between the neutron numbers N = 78 and N = 80. A γ deformation of 34 was deduced for both 139 Pr and 141 Pm. (author)

  20. Nuclear structure and reaction studies at medium energies

    International Nuclear Information System (INIS)

    Hoffmann, G.W.; Ray, R.L.

    1990-10-01

    This document constitutes the (1988--1991) technical progress report for the ongoing medium energy physics research program supported by the US Department of Energy through special Research Grant FG05-88ER40444. The experiments discussed are conducted at the Los Alamos National Laboratory's (LANL) Clinton P. Anderson Meson Physics Facility (LAMPF), the Alternating Gradient Synchrotron (AGS) facility of the Brookhaven National Laboratory (BNL), and at the Fermi National Accelerator Laboratory (FNAL). The overall motivation for the work discussed in this document is driven by three main objectives: (1) provide hadron-nucleon and hadron-nucleus scattering data which serve to facilitate the study of effective two-body interactions, test (and possibly determine) nuclear structure, and help study reaction mechanisms and dynamics;(2) provide unique, first-of-a-kind ''exploratory'' hadron-nucleus scattering data in the hope that such data will lead to discovery of new phenomena and new physics; and (3) perform precision tests of fundamental interactions, such as rare decay searches, whose observation would imply fundamental new physics

  1. Validity of medium-energy collimator for sentinel lymphoscintigraphy imaging

    International Nuclear Information System (INIS)

    Tsushima, Hiroyuki; Yamanaga, Takashi; Shimonishi, Yoshihiro; Kosakai, Kazuhisa; Takayama, Teruhiko; Kizu, Hiroto; Noguchi, Atsushi; Onoguchi, Masahisa

    2007-01-01

    For lymphoscintigraphy to detect sentinel lymph node (SLN) in the breast cancer, the lead shielding of the injection site is often used to avoid artifacts, but the method tends to cover the neighborhood SLN. To exclude this defect, authors developed ME (medium-energy) method where ME collimator and energy setting shifted to its higher region were employed. This paper described the development and validity evaluation of the ME method. Performed were examinations with 3 acrylic phantoms of the injection site (IS), LN and combination of IS+LN (CB): IS was a cylinder, containing 40 MBq of 99m Tc-pertechnetate and LN, a plate with 30 sealed holes having 0.78-400 kBq. CB phantom consisted from LN-simulating holes (each, 40 kBq) placed linearly around the center of IS in H and S directions. Imaging was conducted with 2 kinds of 2-detector gamma camera, FORTE (ADAGA) and DSX rectangular (Sopha Medical Corp.). CB phantom was found optimally visualized by ME collimator at 146, rather than 141, keV. In clinic, 99m Tc-Sn-colloid 40 MBq was given near the tumor of a patient and imaging was done with or without the lead shield with FORTE equipped with low energy high-resolution or ME collimator for their comparison. The present ME method described above set at 146 keV was found to give the image with excellent contrast and without false positive when compared with the lead shield method hitherto. (R.T.)

  2. Inelastic collisions of medium energy atomic elements. Qualitative model of energy losses during collisions

    International Nuclear Information System (INIS)

    Pustovit, A.N.

    2006-01-01

    A new approach to the theoretical description of energy losses of atomic particle of medium energy during their interaction with the substance is proposed. The corner-stone of this approach is the supposition that all of the collision processes have inelastic nature during particle movement through the substance, while the calculation of the atomic particles braking is based on the law of their dispersion and the laws of energy and momentum conservation at the inelastic collisions. It is shown that inelastic atomic collision there are three dispersion zones for the only potential interaction with different laws, which characterize energy losses. The application conditions of this approach are determined [ru

  3. Efficiency of free-energy calculations of spin lattices by spectral quantum algorithms

    International Nuclear Information System (INIS)

    Master, Cyrus P.; Yamaguchi, Fumiko; Yamamoto, Yoshihisa

    2003-01-01

    Ensemble quantum algorithms are well suited to calculate estimates of the energy spectra for spin-lattice systems. Based on the phase estimation algorithm, these algorithms efficiently estimate discrete Fourier coefficients of the density of states. Their efficiency in calculating the free energy per spin of general spin lattices to bounded error is examined. We find that the number of Fourier components required to bound the error in the free energy due to the broadening of the density of states scales polynomially with the number of spins in the lattice. However, the precision with which the Fourier components must be calculated is found to be an exponential function of the system size

  4. Zero-Magnetic-Field Spin Splitting of Polaron's Ground State Energy Induced by Rashba Spin-Orbit Interaction

    International Nuclear Information System (INIS)

    Liu Jia; Xiao Jingling

    2006-01-01

    We study theoretically the ground state energy of a polaron near the interface of a polar-polar semiconductor by considering the Rashba spin-orbit (SO) coupling with the Lee-Low-Pines intermediate coupling method. Our numerical results show that the Rashba SO interaction originating from the inversion asymmetry in the heterostructure splits the ground state energy of the polaron. The electron areal density and vector dependence of the ratio of the SO interaction to the total ground state energy or other energy composition are obvious. One can see that even without any external magnetic field, the ground state energy can be split by the Rashba SO interaction, and this split is not a single but a complex one. Since the presents of the phonons, whose energy gives negative contribution to the polaron's, the spin-splitting states of the polaron are more stable than electron's.

  5. Development of global medium-energy nucleon-nucleus optical model potentials

    International Nuclear Information System (INIS)

    Madland, D.G.; Sierk, A.J.

    1997-01-01

    The authors report on the development of new global optical model potentials for nucleon-nucleus scattering at medium energies. Using both Schroedinger and Dirac scattering formalisms, the goal is to construct a physically realistic optical potential describing nucleon-nucleus elastic scattering observables for a projectile energy range of (perhaps) 20 meV to (perhaps) 2 GeV and a target mass range of 16 to 209, excluding regions of strong nuclear deformation. They use a phenomenological approach guided by conclusions from recent microscopic studies. The experimental database consists largely of proton-nucleus elastic differential cross sections, analyzing powers, spin-rotation functions, and total reaction cross sections, and neutron-nucleus total cross sections. They will use this database in a nonlinear least-squares adjustment of optical model parameters in both relativistic equivalent Schroedinger (including relativistic kinematics) and Dirac (second-order reduction) formalisms. Isospin will be introduced through the standard Lane model and a relativistic generalization of that model

  6. Medium Energy measurements on N-N parameters

    International Nuclear Information System (INIS)

    Ambrose, D.; Bachman, M.; Coffey, P.; Glass, G.; Jobst, B.; McNaughton, K.H.; Nguyen, C.; Riley, P.J.

    1992-12-01

    Research is reported on the following topics: Spin transfer measurements in np elastic scattering; pp elastic differential cross section measurements; single pion production in np scattering; and a new search for rare kaon decays (K L →μμ and K L →ee). 68 refs., 33 figs, 3 tabs

  7. Medium energy measurements of N-N parameters

    International Nuclear Information System (INIS)

    Riley, P.J.

    1990-01-01

    This paper discusses the following topics: pp elastic absolute cross section measurement; spin transfer measurements in np elastic scattering; single pion production in np scattering; photoproduction of high P t jets in the wide band beam of the tevatron; and search for K L 0 → μe, K L 0 → ee

  8. Rashba-Zeeman-effect-induced spin filtering energy windows in a quantum wire

    International Nuclear Information System (INIS)

    Xiao, Xianbo; Nie, Wenjie; Chen, Zhaoxia; Zhou, Guanghui; Li, Fei

    2014-01-01

    We perform a numerical study on the spin-resolved transport in a quantum wire (QW) under the modulation of both Rashba spin-orbit coupling (SOC) and a perpendicular magnetic field by using the developed Usuki transfer-matrix method in combination with the Landauer-Büttiker formalism. Wide spin filtering energy windows can be achieved in this system for unpolarized spin injection. In addition, both the width of energy window and the magnitude of spin conductance within these energy windows can be tuned by varying Rashba SOC strength, which can be apprehended by analyzing the energy dispersions and spin-polarized density distributions inside the QW, respectively. Further study also demonstrates that these Rashba-SOC-controlled spin filtering energy windows show a strong robustness against disorders. These findings may not only benefit to further understand the spin-dependent transport properties of a QW in the presence of external fields but also provide a theoretical instruction to design a spin filter device.

  9. Rashba-Zeeman-effect-induced spin filtering energy windows in a quantum wire

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xianbo, E-mail: xxb-11@hotmail.com; Nie, Wenjie [School of Computer, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004 (China); Chen, Zhaoxia [School of Mechatronics Engineering, East China Jiaotong University, Nanchang 330013 (China); Zhou, Guanghui [Department of Physics and Key Laboratory for Low-Dimensional Quantum Structures and Manipulation (Ministry of Education), Hunan Normal University, Changsha 410081 (China); Li, Fei, E-mail: wltlifei@sina.com [Office of Scientific Research, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004 (China)

    2014-06-14

    We perform a numerical study on the spin-resolved transport in a quantum wire (QW) under the modulation of both Rashba spin-orbit coupling (SOC) and a perpendicular magnetic field by using the developed Usuki transfer-matrix method in combination with the Landauer-Büttiker formalism. Wide spin filtering energy windows can be achieved in this system for unpolarized spin injection. In addition, both the width of energy window and the magnitude of spin conductance within these energy windows can be tuned by varying Rashba SOC strength, which can be apprehended by analyzing the energy dispersions and spin-polarized density distributions inside the QW, respectively. Further study also demonstrates that these Rashba-SOC-controlled spin filtering energy windows show a strong robustness against disorders. These findings may not only benefit to further understand the spin-dependent transport properties of a QW in the presence of external fields but also provide a theoretical instruction to design a spin filter device.

  10. Low-energy-state dynamics of entanglement for spin systems

    International Nuclear Information System (INIS)

    Jafari, R.

    2010-01-01

    We develop the ideas of the quantum renormalization group and quantum information by exploring the low-energy-state dynamics of entanglement resources of a system close to its quantum critical point. We demonstrate that low-energy-state dynamical quantities of one-dimensional magnetic systems can show a quantum phase transition point and show scaling behavior in the vicinity of the transition point. To present our idea, we study the evolution of two spin entanglements in the one-dimensional Ising model in the transverse field. The system is initialized as the so-called thermal ground state of the pure Ising model. We investigate the evolution of the generation of entanglement with increasing magnetic field. We obtain that the derivative of the time at which the entanglement reaches its maximum with respect to the transverse field diverges at the critical point and its scaling behaviors versus the size of the system are the same as the static ground-state entanglement of the system.

  11. Low energy properties of the SU(m|n) supersymmetric Haldane-Shastry spin chain

    International Nuclear Information System (INIS)

    Basu-Mallick, B.; Bondyopadhaya, Nilanjan; Sen, Diptiman

    2008-01-01

    The ground state and low energy excitations of the SU(m|n) supersymmetric Haldane-Shastry spin chain are analyzed. In the thermodynamic limit, it is found that the ground state degeneracy is finite only for the SU(m|0) and SU(m|1) spin chains, while the dispersion relation for the low energy and low momentum excitations is linear for all values of m and n. We show that the low energy excitations of the SU(m|1) spin chain are described by a conformal field theory of m non-interacting Dirac fermions which have only positive energies; the central charge of this theory is m/2. Finally, for n≥1, the partition functions of the SU(m|n) Haldane-Shastry spin chain and the SU(m|n) Polychronakos spin chain are shown to be related in a simple way in the thermodynamic limit at low temperatures

  12. Excitation of M1 resonances by medium energy protons

    International Nuclear Information System (INIS)

    Crawley, G.M.; Djalali, C.; Marty, N.

    1983-01-01

    The results of 201 MeV (p,p') studies of ΔL=0 spin-flip transitions at very forward angles are discussed. The reasons for making comparisons between (p,p'), (p,n) and electromagnetic measurements of M1 transitions are outlined. After presenting some of the experimental and theoretical uncertainties, a summary of the results on the Zr isotopes plus other nuclei to mass 140 is given. Results from 48 Ca, the N=28 nuclei 50 Ti, 51 V, 52 Cr and 54 Fe are discussed and compared with (p,n) and electromagnetic measurements. In the Ni isotopes, the T 0 and T 0 +1 components of the 1 + spin-flips transition were observed both in (p,p') and in (p,n) reactions

  13. Medium energy measurements of N-N parameters

    International Nuclear Information System (INIS)

    Ambrose, D.; Bachman, M.; Coffey, P.; Glass, G.; Jobst, B.; McNaughton, Kok Heong; Nguyen, Chau; Riley, P.J.

    1993-01-01

    Most of the effort was devoted to the study of nucleon-nucleon interactions, specifically, spin transfer measurements in np elastic scattering at LAMPF, pp elastic differential cross section measurements at LAMPF, and single-pion production in np scattering. Differential cross sections and analyzing powers are shown for np→ppπ - interactions. A new search for rare K L 0 decays to μe, μμ, and ee is being undertaken. Collaborative work has been begun on a very large, complex collider detector STAR (Solenoidal Tracker At RHIC). STAR is envisioned as a combination of a silicon vertex tracker, a time projection chamber, a set of trigger scintillators, and time-of-flight counters. It would allow measurements of spin dependence at p T above 10 GeV/c

  14. New isomers and medium-spin structure of the 95Y nucleus

    International Nuclear Information System (INIS)

    Urban, W.; Sieja, K.; Simpson, G. S.; Faust, H.; Rzaca-Urban, T.; Zlomaniec, A.; Lukasiewicz, M.; Smith, A. G.; Durell, J. L.; Smith, J. F.; Varley, B. J.; Nowacki, F.; Ahmad, I.

    2009-01-01

    Excited states in 95 Y, populated following the spontaneous fission of 248 Cm and 252 Cf and following fission of 235 U induced by thermal neutrons, were studied by means of γ spectroscopy using the EUROGAM2 and GAMMASPHERE multidetector Ge arrays and the LOHENGRIN fission-fragment separator, respectively. We have found a new (17/2 - ) isomer in 95 Y at 3142.2 keV with a half-life of T 1/2 =14.9(5) ns. Another isomer was identified in 95 Y at 5022.1 keV and it was assigned a spin-parity (27/2 - ). For this isomer a half-life of T 1/2 =65(4) ns was determined and four decay branches were found, including an E3 decay. A new E3 decay branch was also found for the known, 1087.5-keV isomer in 95 Y, for which we measured a half-life of 51.2(9) μs. The B(E3) and B(E1) transition rates, of 2.0 and 3.8x10 -7 W.u., respectively, observed in 95 Y are significantly lower than in the neighboring 96 Zr core, suggesting that octupole correlations in this region are mainly due to the coupling of proton Δj=3 orbitals. Shell-model calculations indicate that the (27/2 - ) isomer in 95 Y corresponds to the πg 9/2 ν(g 7/2 h 11/2 ) maximally aligned configuration and that all three isomers in 95 Y decay, primarily, by M2 transitions between proton g 9/2 and f 5/2 orbitals.

  15. Spin-flip inelastic scattering in electron energy loss spectroscopy of a ferromagnetic metal

    International Nuclear Information System (INIS)

    Yin, S.; Tosatti, E.

    1981-08-01

    We calculate the spin polarization occuring during electron inelastic scattering from electron-hole pairs in a model ferromagnetic metal. The polarization is found to have contributions from unequal spin flip as well as non-flip energy loss rates. Our results indicate an asymmetry of the order of a few percent with parameters roughly modeling Fsub(e). The possibilities of comparison with experiments in the presence of simultaneous spin-polarizing elastic scattering are discussed. (author)

  16. Frequency and wavenumber selective excitation of spin waves through coherent energy transfer from elastic waves

    OpenAIRE

    Hashimoto, Yusuke; Bossini, Davide; Johansen, Tom H.; Saitoh, Eiji; Kirilyuk, Andrei; Rasing, Theo

    2017-01-01

    Using spin-wave tomography (SWaT), we have investigated the excitation and the propagation dynamics of optically-excited magnetoelastic waves, i.e. hybridized modes of spin waves and elastic waves, in a garnet film. By using time-resolved SWaT, we reveal the excitation dynamics of magnetoelastic waves through coherent-energy transfer between optically-excited pure-elastic waves and spin waves via magnetoelastic coupling. This process realizes frequency and wavenumber selective excitation of s...

  17. Technology spin-offs from the magnetic fusion energy program

    International Nuclear Information System (INIS)

    1982-05-01

    A description is given of 138 possible spin-offs from the magnetic fusion program. The spin-offs cover the following areas: (1) superconducting magnets, (2) materials technology, (3) vacuum systems, (4) high frequency and high power rf, (5) electronics, (6) plasma diagnostics, (7) computers, and (8) particle beams

  18. Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jlab

    Energy Technology Data Exchange (ETDEWEB)

    Abeyratne, S; Ahmed, S; Barber, D; Bisognano, J; Bogacz, A; Castilla, A; Chevtsov, P; Corneliussen, S; Deconinck, W; Degtiarenko, P; Delayen, J; Derbenev, Ya; DeSilva, S; Douglas, D; Dudnikov, V; Ent, R; Erdelyi, B; Evtushenko, P; Fujii, Yu; Filatov, Yury; Gaskell, D; Geng, R; Guzey, V; Horn, T; Hutton, A; Hyde, C; Johnson, R; Kim, Y; Klein, F; Kondratenko, A; Kondratenko, M; Krafft, G; Li, R; Lin, F; Manikonda, S; Marhauser, F; McKeown, R; Morozov, V; Dadel-Turonski, P; Nissen, E; Ostroumov, P; Pivi, M; Pilat, F; Poelker, M; Prokudin, A; Rimmer, R; Satogata, T; Sayed, H; Spata, M; Sullivan, M; Tennant, C; Terzic, B; Tiefenback, M; Wang, M; Wang, S; Weiss, C; Yunn, B

    2012-08-01

    Researchers have envisioned an electron-ion collider with ion species up to heavy ions, high polarization of electrons and light ions, and a well-matched center-of-mass energy range as an ideal gluon microscope to explore new frontiers of nuclear science. In its most recent Long Range Plan, the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and the National Science Foundation endorsed such a collider in the form of a 'half-recommendation.' As a response to this science need, Jefferson Lab and its user community have been engaged in feasibility studies of a medium energy polarized electron-ion collider (MEIC), cost-effectively utilizing Jefferson Lab's already existing Continuous Electron Beam Accelerator Facility (CEBAF). In close collaboration, this community of nuclear physicists and accelerator scientists has rigorously explored the science case and design concept for this envisioned grand instrument of science. An electron-ion collider embodies the vision of reaching the next frontier in Quantum Chromodynamics - understanding the behavior of hadrons as complex bound states of quarks and gluons. Whereas the 12 GeV Upgrade of CEBAF will map the valence-quark components of the nucleon and nuclear wave functions in detail, an electron-ion collider will determine the largely unknown role sea quarks play and for the first time study the glue that binds all atomic nuclei. The MEIC will allow nuclear scientists to map the spin and spatial structure of quarks and gluons in nucleons, to discover the collective effects of gluons in nuclei, and to understand the emergence of hadrons from quarks and gluons. The proposed electron-ion collider at Jefferson Lab will collide a highly polarized electron beam originating from the CEBAF recirculating superconducting radiofrequency (SRF) linear accelerator (linac) with highly polarized light-ion beams or unpolarized light- to heavy-ion beams from a new ion accelerator and storage complex. Since the very

  19. Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jlab

    International Nuclear Information System (INIS)

    Abeyratne, S.; Accardi, A.; Ahmed, S.; Barber, D.; Bisognano, J.; Bogacz, A.; Castilla, A.; Chevtsov, P.; Corneliussen, S.; Deconinck, W.; Degtiarenko, P.; Delayen, J.; Derbenev, Ya.; DeSilva, S.; Douglas, D.; Dudnikov, V.; Ent, R.; Erdelyi, B.; Evtushenko, P.; Fujii, Yu; Filatov, Yury; Gaskell, D.; Geng, R.; Guzey, V.; Horn, T.; Hutton, A.; Hyde, C.; Johnson, R.; Kim, Y.; Klein, F.; Kondratenko, A.; Kondratenko, M.; Krafft, G.; Li, R.; Lin, F.; Manikonda, S.; Marhauser, F.; McKeown, R.; Morozov, V.; Dadel-Turonski, P.; Nissen, E.; Ostroumov, P.; Pivi, M.; Pilat, F.; Poelker, M.; Prokudin, A.; Rimmer, R.; Satogata, T.; Sayed, H.; Spata, M.; Sullivan, M.; Tennant, C.; Terzic, B.; Tiefenback, M.; Wang, H.; Wang, S.; Weiss, C.; Yunn, B.; Zhang, Y.

    2012-01-01

    Researchers have envisioned an electron-ion collider with ion species up to heavy ions, high polarization of electrons and light ions, and a well-matched center-of-mass energy range as an ideal gluon microscope to explore new frontiers of nuclear science. In its most recent Long Range Plan, the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and the National Science Foundation endorsed such a collider in the form of a 'half-recommendation.' As a response to this science need, Jefferson Lab and its user community have been engaged in feasibility studies of a medium energy polarized electron-ion collider (MEIC), cost-effectively utilizing Jefferson Lab's already existing Continuous Electron Beam Accelerator Facility (CEBAF). In close collaboration, this community of nuclear physicists and accelerator scientists has rigorously explored the science case and design concept for this envisioned grand instrument of science. An electron-ion collider embodies the vision of reaching the next frontier in Quantum Chromodynamics - understanding the behavior of hadrons as complex bound states of quarks and gluons. Whereas the 12 GeV Upgrade of CEBAF will map the valence-quark components of the nucleon and nuclear wave functions in detail, an electron-ion collider will determine the largely unknown role sea quarks play and for the first time study the glue that binds all atomic nuclei. The MEIC will allow nuclear scientists to map the spin and spatial structure of quarks and gluons in nucleons, to discover the collective effects of gluons in nuclei, and to understand the emergence of hadrons from quarks and gluons. The proposed electron-ion collider at Jefferson Lab will collide a highly polarized electron beam originating from the CEBAF recirculating superconducting radiofrequency (SRF) linear accelerator (linac) with highly polarized light-ion beams or unpolarized light- to heavy-ion beams from a new ion accelerator and storage complex. Since the very

  20. Nuclear reactions of high energy deuterons with medium mass targets

    International Nuclear Information System (INIS)

    Numajiri, Masaharu; Miura, Taichi; Oki, Yuichi

    1994-01-01

    Formation cross sections of product nuclides in the nuclear reactions of medium mass targets by 10 GeV deuterons were measured with a gamma-ray spectroscopy. The measured data were compared with the cross sections of 12 GeV protons. (author)

  1. Home energy monitors : Impact over the medium-term

    NARCIS (Netherlands)

    Van Dam, S.S.; Bakker, C.A.; Van Hal, J.D.M.

    2010-01-01

    Home Energy Management Systems (HEMS), e.g. energy monitors, are intermediary products that can visualize, manage, and/or monitor the energy use of other products or whole households. HEMS increasingly receive attention for their role in energy conservation in households. A literature review and a

  2. A protocol describing the use of a recombinant protein-based, animal product-free medium (APEL) for human embryonic stem cell differentiation as spin embryoid bodies.

    Science.gov (United States)

    Ng, Elizabeth S; Davis, Richard; Stanley, Edouard G; Elefanty, Andrew G

    2008-01-01

    In order to promote the uniform and reproducible differentiation of human embryonic stem cells (HESCs) in response to exogenously added growth factors, we have developed a method (spin embryoid bodies (EBs)) that uses a recombinant protein-based, animal product-free medium in which HESCs are aggregated by centrifugation to form EBs. In this protocol we describe the formulation of this medium, denoted APEL (Albumin Polyvinylalcohol Essential Lipids), and its use in spin EB differentiation of HESCs. We also describe a more economical variant, BPEL (Bovine Serum Albumin (BSA) Polyvinylalchohol Essential Lipids), in which BSA replaces the recombinant human albumin. The integration of a medium that includes only defined and recombinant components with a defined number of cells to initiate EB formation results in a generally applicable, robust platform for growth factor-directed HESC differentiation.

  3. Spin-flip processes in low-energy Fe17+ + He collisions

    International Nuclear Information System (INIS)

    Bruch, R.; Altick, P.L.; Rauscher, E.; Wang, H.; Schneider, D.

    1993-01-01

    Spin-nonconserving electron transfer processes violating the ''Wigner rule'' have been studied for slow multiply charged ion-atom collisions. Experimentally a strong population of highly metastable sodium-like quartet states in low energy Fe 17+ + He single collision events has been observed. The possibility of double-electron capture plus spin-flip mechanisms has been discussed experimentally and theoretically, Our theoretical model using time dependent perturbation theory predicts that spin-flip processes are as likely as no spin flip under the conditions of our experiment

  4. Design and performance of a spin-polarized electron energy loss spectrometer with high momentum resolution

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyev, D.; Kirschner, J. [Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany)

    2016-08-15

    We describe a new “complete” spin-polarized electron energy loss spectrometer comprising a spin-polarized primary electron source, an imaging electron analyzer, and a spin analyzer of the “spin-polarizing mirror” type. Unlike previous instruments, we have a high momentum resolution of less than 0.04 Å{sup −1}, at an energy resolution of 90-130 meV. Unlike all previous studies which reported rather broad featureless data in both energy and angle dependence, we find richly structured spectra depending sensitively on small changes of the primary energy, the kinetic energy after scattering, and of the angle of incidence. The key factor is the momentum resolution.

  5. LOS ALAMOS: the future of medium energy physics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    A 'Workshop on Program Options in Intermediate Energy Physics' was recently held at LAMPF and the topics discussed there are summarized. The purpose of the meeting was to establish priorities for experimental research at intermediate energies. (W.D.L.).

  6. Analysis of possibilities for a spin flip in high energy electron ring HERA

    International Nuclear Information System (INIS)

    Stres, S.; Pestotnik, R.

    2007-01-01

    In a high energy electron ring the spins of electrons become spontaneously polarized via the emission of spin-flip synchrotron radiation. By employing a radio frequency (RF) radial dipole field kicker, particle spin directions can be rotated slowly over many turns. A model which couples three dimensional spin motion and longitudinal particle motion was constructed to describe non-equilibrium spin dynamics in high energy electron storage rings. The effects of a stochastic synchrotron radiation on the orbital motion in the accelerator synchrotron plane and its influence on the spin motion are studied. The main contributions to the spin motion, the synchrotron oscillations and the stochastic synchrotron radiation, have different influence on the spin polarization reversal in different regions of the parameter space. The results indicate that polarization reversal might be obtained in high energy electron storage rings with a significant noise even with relatively small strengths of a perturbing magnetic field. The only experimental datum avaliable agrees with the model prediction, however further experimental data would be necessary to validate the model

  7. Technical Support Document: 50% Energy Savings Design Technology Packages for Medium Office Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, Brian A.; Wang, Weimin; Lane, Michael D.; Rosenberg, Michael I.; Liu, Bing

    2009-09-01

    This Technical Support Document (TSD) describes the process and methodology for development of the Advanced Energy Design Guide for Medium Offices (AEDG-MO or the Guide), a design guidance document which intends to provide recommendations for achieving 50% energy savings in medium office buildings that just meet the requirements of ANSI/ASHRAE/IESNA Standard 90.1-2004, Energy Standard for Buildings Except Low-Rise Residential Buildings.

  8. The Energy Savings and Environmental Benefits for Small and Medium Enterprises by Cloud Energy Management System

    Directory of Open Access Journals (Sweden)

    Yen-Chieh Tseng

    2016-06-01

    Full Text Available Small and medium enterprises (SMES play an important role in Taiwan’s economy. The reduction of energy costs and carbon dioxide (CO2 emissions are critical to preserving the environment. This paper uses the experimental results from 65 sites, gathered over two years since 2012, to determine how the integration of Internet communication, cloud computing technologies and a cloud energy management service (cloud EMS can reduce energy consumption by cost-effective means. The EMS has three levels: infrastructure as a service (IaaS, platform as a service (PaaS and software as a service (SaaS. Working jointly with ChungHwa Telecom, Taiwan’s leading telecom service provider, data from detection devices, control devices, air-conditioning and lighting systems are all uploaded to a cloud EMS platform, to give a so called intelligent energy management network application service platform (IEN-ASP. Various energy saving management functions are developed using this platform: (1 air conditioning optimization; (2 lighting system optimization; (3 scheduling control; (4 power billing control and (5 occupancy detection and timing control. Using the international performance measurement and verification protocol (IPMVP, the energy used at the test sites, before and after the use of the IEN-ASP, are compared to calculate the energy saved. The experimental results show that there is an average energy saving of 5724 kWh per year, which represents a saving ratio of 5.84%. This translates to a total reduction in CO2 emissions of 9,926,829 kg per year. Using the data collected, a regression model is used to demonstrate the correlation between the power that is consumed, the energy that is saved and the area of the sites. Another interesting result is that, if the experimental sites are maintained by experienced electricians or other personnel and EMS protocols are followed, the energy saving can be as great as 6.59%.

  9. Energy technologies for post Kyoto targets in the medium term

    International Nuclear Information System (INIS)

    Soenderberg Petersen, L.; Larsen, H.

    2003-09-01

    The Risoe International Energy Conference took place 19 - 21 May 2003 and the aim was to present and discuss new developments and trends in energy technologies which may become main contributors to the energy scene in 15 to 20 years. The conference addressed R and D related to the individual technologies as well as system integration. The proceedings are prepared from papers presented at the conference and received with corrections, if any, until the final deadline on 25 June 2003. (au)

  10. Energy technologies for post Kyoto targets in the medium term

    Energy Technology Data Exchange (ETDEWEB)

    Soenderberg Petersen, L; Larsen, H [eds.

    2003-09-01

    The Risoe International Energy Conference took place 19 - 21 May 2003 and the aim was to present and discuss new developments and trends in energy technologies which may become main contributors to the energy scene in 15 to 20 years. The conference addressed R&D related to the individual technologies as well as system integration. The proceedings are prepared from papers presented at the conference and received with corrections, if any, until the final deadline on 25 June 2003. (au)

  11. On the TAP Free Energy in the Mixed p-Spin Models

    Science.gov (United States)

    Chen, Wei-Kuo; Panchenko, Dmitry

    2018-05-01

    Thouless et al. (Phys Mag 35(3):593-601, 1977), derived a representation for the free energy of the Sherrington-Kirkpatrick model, called the TAP free energy, written as the difference of the energy and entropy on the extended configuration space of local magnetizations with an Onsager correction term. In the setting of mixed p-spin models with Ising spins, we prove that the free energy can indeed be written as the supremum of the TAP free energy over the space of local magnetizations whose Edwards-Anderson order parameter (self-overlap) is to the right of the support of the Parisi measure. Furthermore, for generic mixed p-spin models, we prove that the free energy is equal to the TAP free energy evaluated on the local magnetization of any pure state.

  12. Violation of a Bell-like inequality for spin-energy entanglement in neutron polarimetry

    International Nuclear Information System (INIS)

    Sponar, S.; Klepp, J.; Zeiner, C.; Badurek, G.; Hasegawa, Y.

    2010-01-01

    Violation of a Bell-like inequality for a spin-energy entangled neutron state has been demonstrated in a polarimetric experiment. The proposed inequality, in Clauser-Horne-Shimony-Holt (CHSH) formalism, relies on correlations between the spin and energy degree of freedom in a single-neutron system. The correlation function S CHSH is determined to be 2.333±0.002≤/2, which violates the Bell-like CHSH inequality by more than 166 standard deviations.

  13. Optically tunable spin-exchange energy at donor:acceptor interfaces in organic solar cells

    International Nuclear Information System (INIS)

    Li, Mingxing; Wang, Hongfeng; He, Lei; Zang, Huidong; Xu, Hengxing; Hu, Bin

    2014-01-01

    Spin-exchange energy is a critical parameter in controlling spin-dependent optic, electronic, and magnetic properties in organic materials. This article reports optically tunable spin-exchange energy by studying the line-shape characteristics in magnetic field effect of photocurrent developed from intermolecular charge-transfer states based on donor:acceptor (P3HT:PCBM) system. Specifically, we divide magnetic field effect of photocurrent into hyperfine (at low field   10 mT) regimes. We observe that increasing photoexcitation intensity can lead to a significant line-shape narrowing in magnetic field effect of photocurrent occurring at the spin-exchange regime. We analyze that the line-shape characteristics is essentially determined by the changing rate of magnetic field-dependent singlet/triplet ratio when a magnetic field perturbs the singlet-triplet transition through spin mixing. Based on our analysis, the line-shape narrowing results indicate that the spin-exchange energy at D:A interfaces can be optically changed by changing photoexcitation intensity through the interactions between intermolecular charge-transfer states. Therefore, our experimental results demonstrate an optical approach to change the spin-exchange energy through the interactions between intermolecular charge-transfer states at donor:acceptor interface in organic materials.

  14. The origin of nuclear spin and its effect durning intermediate energy heavy ion collisions

    International Nuclear Information System (INIS)

    Zhang Guoqiang; Cao Xiguang; Fu Yao; Ma Yugang; Cai Xiangzhou; Wang Hongwei; Fang Deqing; Tian Wendong; Chen Jingen; Guo Wei; Liu Guihua

    2010-01-01

    We use the heavy-ion phase-space exploration (HIPSE) model to discuss the origin of the nuclear spin and its effect in Intermediate energy nuclear reaction. It is found that the spin of projectile depends on the impact parameter of the reaction system heavily, while on the violence lightly by contrast. Some interesting multifragmentation phenomena related to the spin are shown, especially those of phase transition. At the same time, the role of excited energy for multifragmentation is also invested. We find the later plays a more robust role durning the nuclear disintegration. (authors)

  15. Origin of the finite nuclear spin and its effect in intermediate energy heavy ion collisions

    International Nuclear Information System (INIS)

    Zhang Guoqiang; Cao Xiguang; Fu Yao

    2012-01-01

    The heavy-ion phase-space exploration (HIPSE) model is used to discuss the origin of the nuclear spin in intermediate energy heavy-ion collision (HIC). The spin of maximal projectile-like fragment is found to depend strongly on impact parameter of a reaction system,while it relates weakly to the collision violence. Some interesting multi-fragmentation phenomena related to the spin are shown. We also found that the excitation energy in the de-excitation stage plays a robust role at the de-excitation stage in HIC. (authors)

  16. Photodisintegration of the deuteron at medium and high energies

    International Nuclear Information System (INIS)

    Lee, T.S.H.

    1991-01-01

    We report the results from a unitary πNN calculation of γd →np reaction up to the Δ-excitation energy region, and the preliminary results from a light-front calculation at high energies. 7 refs., 3 figs

  17. Coordination of bidding strategies in day-ahead energy and spinning reserve markets

    International Nuclear Information System (INIS)

    Fushuan Wen; David, A.K.

    2002-01-01

    In this paper, the problem of building optimally coordinated bidding strategies for competitive suppliers in day-ahead energy and spinning reserve markets is addressed. It is assumed that each supplier bids 24 linear energy supply functions and 24 linear spinning reserve supply functions, one for each hour, into the energy and spinning reserve markets, respectively, and each market is cleared separately and simultaneously for all the 24 delivery hours. Each supplier makes decisions on unit commitment and chooses the coefficients in the linear energy and spinning reserve supply functions to maximise total benefits, subject to expectations about how rival suppliers will bid in both markets. Two different bidding schemes have been suggested for each hour, and based on them an overall coordinated bidding strategy in the day-ahead energy and spinning reserve market is then developed. Stochastic optimisation models are first developed to describe these two different bidding schemes and a genetic algorithm (GA) is then used to build the optimally coordinated bidding strategies for each scheme and to develop an overall bidding strategy for the day-ahead energy and spinning reserve markets. A numerical example is utilised to illustrate the essential features of the method. (Author)

  18. Project appraisal for small and medium size wind energy installation: The Italian wind energy policy effects

    International Nuclear Information System (INIS)

    Fera, M.; Iannone, R.; Macchiaroli, R.; Miranda, S.; Schiraldi, M.M.

    2014-01-01

    In the last few years, the distributed energy production from small wind turbines (i.e.<200 kWp) has developed into a relevant business opportunity for different investors in Italy. The market, especially in Italy, has rapidly grown, achieving 9 MWp only in 2011, with an increase from 1.5 MW in 2009 to 13.3 MW at the end of 2011. This paper reports the results of a case study on the installation of several small wind turbines. It aims to provide an analysis of the conditions in Italy that make it possible to install these machines and offer a reliable reference for designing, planning, and controlling small wind turbine projects while focusing on the strategic variables of time, cost, and quality used by typical enterprises in the investment projects. The results are relevant to investors as well as engineering, procurement, and construction companies involved in this new sector, which must understand Italy’s renewable energy policy and its effects in practice. Moreover, certain national energy policy conclusions are reported and discussed in this paper. To properly study the sector, the data on time, cost and quality are analysed using typical project management tools. - Highlights: • Focus on the Italian wind energy sector. • Analysis of Italian policy effects. • Focus on small/medium size wind energy machines

  19. Statistical error of spin transfer to hyperon at RHIC energy

    International Nuclear Information System (INIS)

    Han Ran; Mao Yajun

    2009-01-01

    From the RHIC/PHENIX experiment data, it is found that the statistical error of spin transfer is few times larger than the statistical error of the single spin asymmetry. In order to verify the difference between σDLL and σAL, the linear least squares method was used to check it first, and then a simple Monte-Carlo simulation to test this factor again. The simulation is consistent with the calculation result which indicates that the few times difference is reasonable. (authors)

  20. Partial cross sections of helium satellites at medium photon energies

    Energy Technology Data Exchange (ETDEWEB)

    Wehlitz, R.; Sellin, I.A. [Univ. of Tennessee, Knoxville, TN (United States); Hemmers, O. [Univ. of Nevada, Las Vegas, NV (United States)] [and others

    1997-04-01

    Still of current interest is the important role of single ionization with excitation compared to single ionization alone. The coupling between the electrons and the incoming photon is a single-particle operator. Thus, an excitation in addition to an ionization, leading to a so-called satellite line in a photoelectron spectrum, is entirely due to electron-electron interaction and probes the electron correlation in the ground and final state. Therefore the authors have undertaken the study of the intensity of helium satellites He{sup +}nl (n = 2 - 6) relative to the main photoline (n = 1) as a function of photon energy at photon energies well above threshold up to 900 eV. From these results they could calculate the partial cross-sections of the helium satellites. In order to test the consistency of their satellite-to-1s ratios with published double-to-single photoionization ratios, the authors calculated the double-to-single photoionization ratio from their measured ratios using the theoretical energy-distribution curves of Chang and Poe and Le Rouzo and Dal Cappello which proved to be valid for photon energies below 120 eV. These calculated double-to-single ionization ratios agree fairly well with recent ion measurements. In the lower photon energy range the authors ratios agree better with the ratios of Doerner et al. while for higher photon energies the agreement is better with the values of Levin et al.

  1. Partial cross sections of helium satellites at medium photon energies

    International Nuclear Information System (INIS)

    Wehlitz, R.; Sellin, I.A.; Hemmers, O.

    1997-01-01

    Still of current interest is the important role of single ionization with excitation compared to single ionization alone. The coupling between the electrons and the incoming photon is a single-particle operator. Thus, an excitation in addition to an ionization, leading to a so-called satellite line in a photoelectron spectrum, is entirely due to electron-electron interaction and probes the electron correlation in the ground and final state. Therefore the authors have undertaken the study of the intensity of helium satellites He + nl (n = 2 - 6) relative to the main photoline (n = 1) as a function of photon energy at photon energies well above threshold up to 900 eV. From these results they could calculate the partial cross-sections of the helium satellites. In order to test the consistency of their satellite-to-1s ratios with published double-to-single photoionization ratios, the authors calculated the double-to-single photoionization ratio from their measured ratios using the theoretical energy-distribution curves of Chang and Poe and Le Rouzo and Dal Cappello which proved to be valid for photon energies below 120 eV. These calculated double-to-single ionization ratios agree fairly well with recent ion measurements. In the lower photon energy range the authors ratios agree better with the ratios of Doerner et al. while for higher photon energies the agreement is better with the values of Levin et al

  2. Gamma-ray astronomy in the medium energy (10-50 MeV) range

    International Nuclear Information System (INIS)

    Kniffen, D.A.; Bertsch, D.L.; Palmeira, R.A.R.; Rao, K.R.

    1977-01-01

    Gamma-ray astronomy in the medium energy (10-50 MeV) range can provide unique information with which to study many astrophysical problems. Observations in the 10-50 MeV range provide the cleanest window with which to view the isotropic diffuse component of the radiation and to study the possible cosmological implications of the spectrum. For the study of compact sources, this is the important region between the X-ray sky and the vastly different γ-ray sky seen by SAS-2 and COS-B. To understand the implications of medium energy γ-ray astronomy to the study of the galactic diffuse γ-radiation, the model developed to explain the high energy γ-ray observations of SAS-2 is extended to the medium energy range. This work illustrates the importance of medium energy γ-ray astronomy for studying the electromagnetic component of the galactic cosmic rays. To observe the medium energy component of the intense galactic center γ-ray emission, two balloon flights of a medium energy γ-ray spark chamber telescope were flown in Brazil in 1975. These results indicate the emission is higher than previously thought and above the predictions of the theoretical model

  3. A Program in Medium-Energy Nuclear Physics

    International Nuclear Information System (INIS)

    Feldman, Gerald

    2015-01-01

    We report here on the final stages of the Berman grant. The study of the spectrum and properties of the excited states of the nucleon (the N* states) is one of the highest-priority goals of nuclear physics and one of the major programs of Jefferson Lab, especially in Hall B. We have most recently focused our attention on exclusive studies (in both spin and strangeness) of the neutron in the deuteron. Our g13 experiment, @@@Production of Kaons from the Deuteron with Polarized Photons@@@ [Nadel-Turonski (2006)], was carried out between October 2006 and June 2007. This experiment was done using both linearly and circularly polarized photons, mainly to try to unscramble the multitude of wide and overlapping N* states and to measure their properties by studying in fine detail their decays into strange-particle reaction channels. To this end, one of our students, Edwin Munevar, has analyzed the @@n@@@K + @@ - reaction channel for his Ph.D. topic. The strangeness-production channels constitute the subject of the original GW group@@@s g13 proposal. But the g13 data set, by virtue of its statistics, polarization, and kinematic coverage, is ideally suited for many other reaction channels as well. Among these is the azimuthal angular asymmetry for deuteron photodisintegration, which was analyzed by another of our students, Nicholas Zachariou, for his Ph.D. topic, with help from Nickolay Ivanov (from the Yerevan Physics Institute in Armenia). This study required a deuterium target and a linearly polarized photon beam.

  4. A Program in Medium-Energy Nuclear Physics

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, Gerald [George Washington Univ., Washington, DC (United States)

    2015-03-23

    We report here on the final stages of the Berman grant. The study of the spectrum and properties of the excited states of the nucleon (the N* states) is one of the highest-priority goals of nuclear physics and one of the major programs of Jefferson Lab, especially in Hall B. We have most recently focused our attention on exclusive studies (in both spin and strangeness) of the neutron in the deuteron. Our g13 experiment, “Production of Kaons from the Deuteron with Polarized Photons” [Nadel-Turonski (2006)], was carried out between October 2006 and June 2007. This experiment was done using both linearly and circularly polarized photons, mainly to try to unscramble the multitude of wide and overlapping N* states and to measure their properties by studying in fine detail their decays into strange-particle reaction channels. To this end, one of our students, Edwin Munevar, has analyzed the γn→K+Σ- reaction channel for his Ph.D. topic. The strangeness-production channels constitute the subject of the original GW group’s g13 proposal. But the g13 data set, by virtue of its statistics, polarization, and kinematic coverage, is ideally suited for many other reaction channels as well. Among these is the azimuthal angular asymmetry for deuteron photodisintegration, which was analyzed by another of our students, Nicholas Zachariou, for his Ph.D. topic, with help from Nickolay Ivanov (from the Yerevan Physics Institute in Armenia). This study required a deuterium target and a linearly polarized photon beam.

  5. Refinement of the AdEPT Medium-Energy Gamma-Ray Science

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to explore the theoretical framework for the relatively unexplored field of medium energy (5--200 MeV) gamma-ray astronomy for a mission concept...

  6. Workshop on Hydrogen Storage and Generation for Medium-Power and -Energy Applications

    National Research Council Canada - National Science Library

    Matthews, Michael

    1998-01-01

    This report summarizes the Workshop on Hydrogen Storage and Generation Technologies for Medium-Power and -Energy Applications which was held on April 8-10, 1997 at the Radisson Hotel Orlando Airport in Orlando, Florida...

  7. Medium energy measurements of n-n parameters. Progress report, January 1-December 31, 1985

    International Nuclear Information System (INIS)

    1986-01-01

    This document constitutes a progress report (1985-86) for the ongoing medium energy nuclear physics research program. A major part of the work has been and will continue to be associated with research done at the Nucleon Physics Laboratory (NPL) at the Los Alamos Meson Physics Facility (LAMPF). The aim of the experimental program is the determination of the nucleon-nucleon amplitudes at medium energy. The required data include both elastic and inelastic experiments, and in addition the measurement of polarization and polarization transfer parameters. We have been emphasizing single pion production measurements using polarized proton beams, and expect that our present data base will provide stringent tests of theoretical models. With the development of the LAMPF high intensity polarized proton source, we expect that a reasonably intense beam of medium energy polarized neutrons will become available, and are planning a series of experiments utilizing polarized neutrons to determine the importance of the I = 0 reaction amplitudes at medium energies

  8. Spin- and energy-dependent tunneling through a single molecule with intramolecular spatial resolution.

    Science.gov (United States)

    Brede, Jens; Atodiresei, Nicolae; Kuck, Stefan; Lazić, Predrag; Caciuc, Vasile; Morikawa, Yoshitada; Hoffmann, Germar; Blügel, Stefan; Wiesendanger, Roland

    2010-07-23

    We investigate the spin- and energy-dependent tunneling through a single organic molecule (CoPc) adsorbed on a ferromagnetic Fe thin film, spatially resolved by low-temperature spin-polarized scanning tunneling microscopy. Interestingly, the metal ion as well as the organic ligand show a significant spin dependence of tunneling current flow. State-of-the-art ab initio calculations including also van der Waals interactions reveal a strong hybridization of molecular orbitals and substrate 3d states. The molecule is anionic due to a transfer of one electron, resulting in a nonmagnetic (S=0) state. Nevertheless, tunneling through the molecule exhibits a pronounced spin dependence due to spin-split molecule-surface hybrid states.

  9. Experimental medium energy physics. Annual progress report, June 1985-May 1986

    International Nuclear Information System (INIS)

    1986-01-01

    During the past year the CMU Medium Energy Physics Group has been involved in the running of three experiments. In addition, software and hardware for two new experiments scheduled to take place over the next few months have been developed. A new proposal, ''Search for a Strangeness -2 Dibaryon Using a 3 He Target,'' was submitted to the Brookhaven Program Advisory Committee and recently approved. In the spring of this year, studies of hypernuclear decay shifted to few body systems. Data on the decay of 5 /sub Λ/He was taken along with preliminary data on 4 /sub Λ/He. This was followed a month later by a run at LEAR to study anti ΛΛ production. The high statistics runs should allow extraction of the spin correlation coefficients not previously obtainable and also includes a detailed study at threshold. In December, a second run at LEAR began the start of anti ΛΣ production studies and tested the ability to measure K/sub s/K/sub s/ production; this channel will be used to search for the ξ(2230) in the summer of 1986. In preparation for the ξ(2230) search, extensive Monte Carlo simulations have been performed at CMU to aid in the design of the detector system. Data analysis routines from hyperon production studies were modified and the first K/sub s/K/sub s/ event was extracted from existing data. The CMU group has had extensive involvement in an experiment to search for strangeness production relativistic heavy ion collisions. Hardware to provide the online analysis and data storage facilities for the experiment has been purchased and developed. CMU personnel has also worked on the development of software with the flexibility required to monitor this complex experiment. 37 refs., 53 figs., 8 tabs

  10. Electrically and magnetically controlled optical spanner based on the transfer of spin angular momentum of light in an optically active medium

    International Nuclear Information System (INIS)

    Chen Lixiang; Zheng Guoliang; She Weilong

    2007-01-01

    An optical spanner is a light beam that can exert a torque on an object. It is demonstrated in this Rapid Communication that, with the aid of applied electric and magnetic fields, a light beam with initially linear polarization and initially zero total spin angular momentum can interact with an optically active medium, resulting in a change of the ratio of left-handed circularly polarized photons to right-handed ones. Thus the total spin angular momentum of the light is changed, which leads to a torque, creating an electrically and magnetically controlled optical spanner on the medium. For a linearly polarized 632.8 nm laser beam incident on a 100-μm-long Ce:Bi 12 TiO 20 whisker crystal with 5 μm radius, if the magnetic field is fixed at -1.8 T, both the left- (right-)handed circularly polarized photon number and the total spin angular momentum vary with the applied electric field in a sinusoidal way, which means the torque exerted by the optical spanner on the crystal also varies sinusoidally with the electric field. It is found that at 50 (or-50) kV/cm, 56% right- (left-)handed circularly polarized photons are translated into left- (right-)handed ones, which corresponds to a transfer of 0.56(ℎ/2π) spin angular momentum contributed by each photon

  11. Universality, maximum radiation, and absorption in high-energy collisions of black holes with spin.

    Science.gov (United States)

    Sperhake, Ulrich; Berti, Emanuele; Cardoso, Vitor; Pretorius, Frans

    2013-07-26

    We explore the impact of black hole spins on the dynamics of high-energy black hole collisions. We report results from numerical simulations with γ factors up to 2.49 and dimensionless spin parameter χ=+0.85, +0.6, 0, -0.6, -0.85. We find that the scattering threshold becomes independent of spin at large center-of-mass energies, confirming previous conjectures that structure does not matter in ultrarelativistic collisions. It has further been argued that in this limit all of the kinetic energy of the system may be radiated by fine tuning the impact parameter to threshold. On the contrary, we find that only about 60% of the kinetic energy is radiated for γ=2.49. By monitoring apparent horizons before and after scattering events we show that the "missing energy" is absorbed by the individual black holes in the encounter, and moreover the individual black-hole spins change significantly. We support this conclusion with perturbative calculations. An extrapolation of our results to the limit γ→∞ suggests that about half of the center-of-mass energy of the system can be emitted in gravitational radiation, while the rest must be converted into rest-mass and spin energy.

  12. Energy-efficient TDMA medium access control protocol scheduling

    NARCIS (Netherlands)

    Havinga, Paul J.M.; Smit, Gerard J.M.

    2000-01-01

    In this paper we study the energy efficiency and channel efficiency of TDMA MAC protocol scheduling mechanisms. Most MAC protocols are based on phase grouping that basically has three phases in a frame: uplink, downlink and reservation. We propose a new mechanism in which we have multiple uplink and

  13. Energy dependent response of plastic scintillation detectors to photon radiation of low to medium energy.

    Science.gov (United States)

    Ebenau, Melanie; Radeck, Désirée; Bambynek, Markus; Sommer, Holger; Flühs, Dirk; Spaan, Bernhard; Eichmann, Marion

    2016-08-01

    Plastic scintillation detectors are promising candidates for the dosimetry of low- to medium-energy photons but quantitative knowledge of their energy response is a prerequisite for their correct use. The purpose of this study was to characterize the energy dependent response of small scintillation detectors (active volume <1 mm(3)) made from the commonly used plastic scintillator BC400. Different detectors made from BC400 were calibrated at a number of radiation qualities ranging from 10 to 280 kV and at a (60)Co beam. All calibrations were performed at the Physikalisch-Technische Bundesanstalt, the National Metrology Institute of Germany. The energy response in terms of air kerma, dose to water, and dose to the scintillator was determined. Conversion factors from air kerma to dose to water and to dose to the scintillator were derived from Monte Carlo simulations. In order to quantitatively describe the energy dependence, a semiempirical model known as unimolecular quenching or Birks' formula was fitted to the data and from this the response to secondary electrons generated within the scintillator material BC400 was derived. The detector energy response in terms of air kerma differs for different scintillator sizes and different detector casings. It is therefore necessary to take attenuation within the scintillator and in the casing into account when deriving the response in terms of dose to water from a calibration in terms of air kerma. The measured energy response in terms of dose to water for BC400 cannot be reproduced by the ratio of mean mass energy-absorption coefficients for polyvinyl toluene to water but shows evidence of quenching. The quenching parameter kB in Birks' formula was determined to be kB = (12.3 ± 0.9) mg MeV(-1) cm(-2). The energy response was quantified relative to the response to (60)Co which is the common radiation quality for the calibration of therapy dosemeters. The observed energy dependence could be well explained with the

  14. Energy dependent response of plastic scintillation detectors to photon radiation of low to medium energy

    Energy Technology Data Exchange (ETDEWEB)

    Ebenau, Melanie, E-mail: melanie.ebenau@tu-dortmunde.de; Sommer, Holger; Spaan, Bernhard; Eichmann, Marion [Fakultät Physik, Technische Universität Dortmund, Otto-Hahn Str. 4a, 44221 Dortmund (Germany); Radeck, Désirée; Bambynek, Markus [Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (Germany); Flühs, Dirk [Universitätsklinikum Essen, Hufelandstr. 55, 45147 Essen (Germany)

    2016-08-15

    Purpose: Plastic scintillation detectors are promising candidates for the dosimetry of low- to medium-energy photons but quantitative knowledge of their energy response is a prerequisite for their correct use. The purpose of this study was to characterize the energy dependent response of small scintillation detectors (active volume <1 mm{sup 3}) made from the commonly used plastic scintillator BC400. Methods: Different detectors made from BC400 were calibrated at a number of radiation qualities ranging from 10 to 280 kV and at a {sup 60}Co beam. All calibrations were performed at the Physikalisch-Technische Bundesanstalt, the National Metrology Institute of Germany. The energy response in terms of air kerma, dose to water, and dose to the scintillator was determined. Conversion factors from air kerma to dose to water and to dose to the scintillator were derived from Monte Carlo simulations. In order to quantitatively describe the energy dependence, a semiempirical model known as unimolecular quenching or Birks’ formula was fitted to the data and from this the response to secondary electrons generated within the scintillator material BC400 was derived. Results: The detector energy response in terms of air kerma differs for different scintillator sizes and different detector casings. It is therefore necessary to take attenuation within the scintillator and in the casing into account when deriving the response in terms of dose to water from a calibration in terms of air kerma. The measured energy response in terms of dose to water for BC400 cannot be reproduced by the ratio of mean mass energy-absorption coefficients for polyvinyl toluene to water but shows evidence of quenching. The quenching parameter kB in Birks’ formula was determined to be kB = (12.3 ± 0.9) mg MeV{sup −1} cm{sup −2}. Conclusions: The energy response was quantified relative to the response to {sup 60}Co which is the common radiation quality for the calibration of therapy dosemeters. The

  15. Spin-neurons: A possible path to energy-efficient neuromorphic computers

    Energy Technology Data Exchange (ETDEWEB)

    Sharad, Mrigank; Fan, Deliang; Roy, Kaushik [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

    2013-12-21

    Recent years have witnessed growing interest in the field of brain-inspired computing based on neural-network architectures. In order to translate the related algorithmic models into powerful, yet energy-efficient cognitive-computing hardware, computing-devices beyond CMOS may need to be explored. The suitability of such devices to this field of computing would strongly depend upon how closely their physical characteristics match with the essential computing primitives employed in such models. In this work, we discuss the rationale of applying emerging spin-torque devices for bio-inspired computing. Recent spin-torque experiments have shown the path to low-current, low-voltage, and high-speed magnetization switching in nano-scale magnetic devices. Such magneto-metallic, current-mode spin-torque switches can mimic the analog summing and “thresholding” operation of an artificial neuron with high energy-efficiency. Comparison with CMOS-based analog circuit-model of a neuron shows that “spin-neurons” (spin based circuit model of neurons) can achieve more than two orders of magnitude lower energy and beyond three orders of magnitude reduction in energy-delay product. The application of spin-neurons can therefore be an attractive option for neuromorphic computers of future.

  16. High-order moments of spin-orbit energy in a multielectron configuration

    Science.gov (United States)

    Na, Xieyu; Poirier, M.

    2016-07-01

    In order to analyze the energy-level distribution in complex ions such as those found in warm dense plasmas, this paper provides values for high-order moments of the spin-orbit energy in a multielectron configuration. Using second-quantization results and standard angular algebra or fully analytical expressions, explicit values are given for moments up to 10th order for the spin-orbit energy. Two analytical methods are proposed, using the uncoupled or coupled orbital and spin angular momenta. The case of multiple open subshells is considered with the help of cumulants. The proposed expressions for spin-orbit energy moments are compared to numerical computations from Cowan's code and agree with them. The convergence of the Gram-Charlier expansion involving these spin-orbit moments is analyzed. While a spectrum with infinitely thin components cannot be adequately represented by such an expansion, a suitable convolution procedure ensures the convergence of the Gram-Charlier series provided high-order terms are accounted for. A corrected analytical formula for the third-order moment involving both spin-orbit and electron-electron interactions turns out to be in fair agreement with Cowan's numerical computations.

  17. Radiation protection and dosimetry problems around medium energy accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovic, R; Pavlovic, S; Markovic, S [Inst. of Nuclear Sciences Vinca, Belgrade (Yugoslavia); Boreli, F [Fac. of Electrical Engineering, Belgrade (Yugoslavia)

    1996-12-31

    In the Institute of Nuclear Sciences `VINCA`, the Accelerator Installation `TESLA`, which is an ion accelerator facility consisting of an isochronous cyclotron `VINCY`, a heavy ion source, a D{sup -} / H{sup -} ion source, three low energy and five high energy experimental channels is now under construction. The Tesla Accelerator Installation should by the principal facility for basic and applied research in physics, chemistry, biology, and material science, as well as for production of radioisotopes, medical diagnostics and therapy with radioisotopes and accelerated particle beams. Some problems in defining radiation protection and safety programme, particularly problems in construction appropriate shielding barriers at the Accelerator Installation `TESLA` are discussed in this paper. (author) 1 fig., 9 refs.

  18. Bibliographic survey of medium energy inclusive reaction data

    International Nuclear Information System (INIS)

    Arthur, E.D.; Madland, D.G.; McClellan, D.M.

    1986-04-01

    A bibliographic survey of inclusive reaction data (experimental and theoretical) for several projectile types having energies between 50 and 1000 MeV has been completed. Approximately one thousand references selected from this survey describe the current state of knowledge for particle-induced inclusive reaction data. The search covered data for the following projectiles: p, d, t, 3 He, 4 He, and lithium ions

  19. Spin and energy effects in heavy quarkonium spectroscopy

    International Nuclear Information System (INIS)

    Gupta, Pramila; Mehrotra, I.

    2016-01-01

    In the present work mc =1.5GeV and mb=5.0 GeV are taken. Once the parameters of the potential are fixed it is solved numerically with reduced radial Schrodinger equation in MATHEMATICA 8.0 by software program obtained by LUCHA et al for each quantum state separately. Spin dependent mass spectra have been computed by adding Breit-Fenni correction term to the interaction (H BF )

  20. Spin flip inelastic scattering in electron energy loss spectroscopy of a ferromagnetic metal

    International Nuclear Information System (INIS)

    Bocchetta, C.J.; Tosatti, E.; Yin, S.

    1986-11-01

    A model ferromagnetic metal is used to calculate the spin-polarization which occurs during inelastic electron-metal scattering with the production of an electron-hole pair. The polarization is found to have contributions from unequal spin-flip as well as non-flip energy loss rates. Our results indicate an asymmetry of the order of a few percent with parameters roughly modelling iron. (author)

  1. Neck instabilities in deep inelastic collisions at medium energies

    International Nuclear Information System (INIS)

    Colonna, M.; Guarnera, A.; Istituto Nazionale di Fisica Nucleare, Catania; Catania Univ.; Di Toro, M.; Latora, V.; Smerzi, A.; Catania Univ.; Jiquan, Z.; Catania Univ.; Lanzhou Univ., GS

    1994-01-01

    A novel reaction mechanism for semi-peripheral heavy ion collisions is discussed due to new features of the nuclear dynamics in the overlapping region. In a very selected beam energy range, between 40 and 70 Me/u, we see the onset of new neck instabilities coupled to an increasing amount of dynamical fluctuations. Expected consequences are a possibility of intermediate mass fragment emission form the neck region and large variances in the projectile-like and target-like observables. (authors). 11 refs., 3 figs

  2. Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Seletskiy, Sergei M. [Univ. of Rochester, NY (United States)

    2005-01-01

    Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the ¯rst cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cool- ing. The Recycler Electron Cooler (REC) is the key component of the Teva- tron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV car- rying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 ¹rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible.

  3. Spin observables at intermediate energies: a tool in viewing the nucleus

    International Nuclear Information System (INIS)

    McClelland, J.B.

    1986-01-01

    This paper attempts to summarize some of the advances made in intermediate nuclear physics through measurements of spin observables, notably in the range of bombarding energies from 100 to 1000 MeV. Relative to measurements of cross section, spin observables offer a highly selective filter in viewing the nucleus. Their general utility is found in their sensitivity to particular nuclear transitions and is further augmented by their simple connections to the NN force. The advantage of higher energies is apparent from the dominance of single-step mechanisms even at large energy losses where general nuclear spin responses may be made. Experimentally, this is an energy range where efficient, high-analyzing-power polarimeters can be coupled with high resolution detection techniques. 29 refs., 5 figs

  4. Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

    International Nuclear Information System (INIS)

    Seletskiy, Sergey M.; Rochester U.

    2005-01-01

    Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the first cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cooling. The Recycler Electron Cooler (REC) is the key component of the Tevatron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV carrying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 (micro)rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible. Chapter 1 is an introduction where I describe briefly the theory and the history of electron cooling, and derive the requirements to the quality of electron beam and requirements to the basic parameters of the Recycler Electron Cooler. Chapter 2 is devoted to the theoretical consideration of the motion of electrons in the cooling section, description of the cooling section and of the measurement of the magnetic fields. In Chapter 3 I consider different factors that increase the effective electron angle in the cooling section and suggest certain algorithms for the suppression of parasitic angles. Chapter 4 is devoted to the measurements of the energy of the electron beam. In the concluding Chapter 5 I review

  5. Tunnel spin polarization versus energy for clean and doped Al2O3 barriers

    NARCIS (Netherlands)

    Park, B.G.; Banerjee, T.; Lodder, J.C.; Jansen, R.

    2007-01-01

    The variation of the tunnel spin-polarization (TSP) with energy is determined using a magnetic tunnel transistor, allowing quantification of the energy dependent TSP separately for both ferromagnet/insulator interfaces and direct correlation with the tunnel magnetoresistance (TMR) measured in the

  6. Tunnel Spin Polarization Versus Energy for Clean and Doped Al2O3 Barriers

    NARCIS (Netherlands)

    Park, B.G.; Banerjee, T.; Lodder, J.C.; Jansen, R.

    2007-01-01

    The variation of the tunnel spin-polarization (TSP) with energy is determined using a magnetic tunnel transistor, allowing quantification of the energy dependent TSP separately for both ferromagnet/insulator interfaces and direct correlation with the tunnel magnetoresistance (TMR) measured in the

  7. Feasibility of a medium-size central cogenerated energy facility, energy management memorandum

    Science.gov (United States)

    Porter, R. W.

    1982-09-01

    The thermal-economic feasibility was studied of a medium-size central cogenerated energy facility designed to serve five varied industries. Generation options included one dual-fuel diesel and one gas turbine, both with waste heat boilers, and five fired boilers. Fuels included natural gas, and for the fired-boiler cases, also low-sulphur coal and municipal refuse. The fired-boiler cogeneration systems employed back-pressure steam turbines. For coal and refuse, the option of steam only without cogeneration was also assessed. The refuse-fired cases utilized modular incinerators. The options provided for a wide range of steam and electrical capacities. Deficient steam was assumed generated independently in existing equipment. Excess electrical power over that which could be displaced was assumed sold to Commonwealth Edison Company under PURPA (Public Utility Regulator Policies Act). The facility was assumed operated by a mutually owned corporation formed by the cogenerated power users. The economic analysis was predicted on currently applicable energy-investment tax credits and accelerated depreciation for a January 1985 startup date. Based on 100% equity financing, the results indicated that the best alternative was the modular-incinerator cogeneration system.

  8. Consequences of wave function orthogonality for medium energy nuclear reactions

    International Nuclear Information System (INIS)

    Noble, J.V.

    1978-01-01

    In the usual models of high-energy bound-state to continuum transitions no account is taken of the orthogonality of the bound and continuum wave functions. This orthogonality induces considerable cancellations in the overlap integrals expressing the transition amplitudes for reactions such as (e,e'p), (γ,p), and (π,N), which are simply not included in the distorted-wave Born-approximation calculations which to date remain the only computationally feasible heirarchy of approximations. The object of this paper is to present a new formulation of the bound-state to continuum transition problem, based upon flux conservation, in which the orthogonality of wave functions is taken into account ab initio. The new formulation, while exact if exact wave functions are used, offers the possibility of using approximate wave functions for the continuum states without doing violence to the cancellations induced by orthogonality. The method is applied to single-particle states obeying the Schroedinger and Dirac equations, as well as to a coupled-channel model in which absorptive processes can be described in a fully consistent manner. Several types of absorption vertex are considered, and in the (π,N) case the equivalence of pseudoscalar and pseudovector πNN coupling is seen to follow directly from wave function orthogonality

  9. Evaluation at the medium energy region for Pb-208 and Bi-209

    International Nuclear Information System (INIS)

    Fukahori, Tokio; Pearlstein, S.

    1991-01-01

    Medium energy nuclear data in the 1--1000 MeV range is necessary to accelerator applications which include spallation neutron sources for radioactive waste treatment and accelerator shielding design, medical applications which include isotopes production and radiation therapy, and space applications. For the design of fission and fusion reactors, the nuclear data file for neutrons below 20 MeV is available and well evaluated. Evaluated nuclear data for protons and data in the medium energy region, however, have not been prepared completely. Evaluation in the medium energy region was performed using the theoretical calculation code ALICE-P or experimental data. In this paper, the evaluation of neutron and proton induced nuclear data for Pb-208 and Bi-209 has been performed using ALICE-P, empirical calculations and new systematics for the fission cross section. The evaluated data are compiled for possible inclusion in the ENDF/B-VI High Energy File. 204 refs., 51 figs., 9 tabs

  10. Description of inelastic nucleus-nucleus interactions at medium energy using dual parton model

    International Nuclear Information System (INIS)

    Polanski, A.; Shmakov, S.Yu.; Uzhinskij, V.V.

    1989-01-01

    It is shown that the dual parton model taking into account the processes of diffraction dissociation to the low mass states and finite energy corrections to the asymptotic Abramovski-Gribov-Kancheli cutting rules allows satisfactory description of existing experimental data on hadron-nucleus and nucleus-nucleus interactions at medium energy. (orig.)

  11. Innovation capabilities and challenges for energy smartdevelopment in medium sized European cities

    NARCIS (Netherlands)

    Lindhult, Erik; Campillo, J.; Dahlquist, E.; Read, S.A.

    2016-01-01

    Transition towards becoming Energy smart city integrating different areas of energy production, distribution and use in a community requires a spectrum of capabilities. The paper reports on findings from the EU planning project PLEEC, involving six medium sized European cities. The purpose of the

  12. Time-domain electromagnetic energy in a frequency-dispersive left-handed medium

    International Nuclear Information System (INIS)

    Cui Tiejun; Kong Jinau

    2004-01-01

    From Maxwell's equations and the Poynting theorem, the time-domain electric and magnetic energy densities are generally defined in the frequency-dispersive media based on the conservation of energy. As a consequence, a general definition of electric and magnetic energy is proposed. Comparing with existing formulations of electric and magnetic energy in frequency-dispersive media, the new definition is more reasonable and is valid in any case. Using the new definition and staring from the equation of motion, we have shown rigorously that the total energy density and the individual electric and magnetic energy densities are always positive in a realistic artificial left-handed medium (LHM) [R. A. Shelby, D. R. Smith, and S. Schultz, Science 292, 77 (2001)], which obeys actually the Lorentz medium model, although such a LHM has negative permittivity and negative permeability simultaneously in a certain frequency range. We have also shown that the conservation of energy is not violated in LHM. The earlier conclusions can be easily extended to the Drude medium model and the cold plasma medium model. Through an exact analysis of a one-dimensional transient current source radiating in LHM, numerical results are given to demonstrate that the work done by source, the power flowing outwards a surface, and the electric and magnetic energy stored in a volume are all positive in the time domain

  13. Multichannel spin polarimeter for energy- and angle-dispersive photoemission measurements; Vielkanal-Spinpolarimeter fuer energie- und winkeldispersive Photoemissionsmessungen

    Energy Technology Data Exchange (ETDEWEB)

    Kolbe, Michaela

    2011-09-09

    Spin polarization measurements of free electrons remain challenging since their first realization by Mott. The relevant quantity of a spin polarimeter is its figure of merit, FoM=S{sup 2}I/I{sub 0}, with the asymmetry function S and the ratio between scattered and primary intensity I/I{sub 0}. State-of-the-art devices are based on single-channel scattering (spin-orbit or exchange interaction) which is characterized by FoM {approx_equal}10{sup -4}. On the other hand, modern hemispherical analyzers feature an efficient multichannel detection of spin-integral intensity with more than 10{sup 4} data points simultaneously. In comparison between spin-resolved and spin-integral electron spectroscopy we are thus faced with a difference in counting efficiency by 8 orders of magnitude. The present work concentrates on the development and investigation of a novel technique for increasing the efficiency in spin-resolved electron spectroscopy by multichannel detection. The spin detector was integrated in a {mu}-metal shielded UHV-chamber and mounted behind a conventional hemispherical analyzer. The electrostatic lens system's geometry was determined by electron-optical simulations. The basic concept is the k {sub parallel} -conserving elastic scattering of the (0,0)-beam on a W(100) scattering crystal under 45 impact angle. It could be demonstrated that app. 960 data points (15 energy and 64 angular points) could be displayed simultaneously on a delayline detector in an energy interval of {approx_equal}3 eV. This leads to a two-dimensional figure of merit of FoM{sub 2D}=1.7. Compared to conventional spin detectors, the new type is thus characterized by a gain in efficiency of 4 orders of magnitude. The operational reliability of the new spin polarimeter could be proven by measurements with a Fe/MgO(100) and O p(1 x 1)/Fe(100)-sample, where results from the literature were reproduced with strongly decreased measuring time. Due to the high intensity it becomes possible, to

  14. Multichannel spin polarimeter for energy- and angle-dispersive photoemission measurements

    International Nuclear Information System (INIS)

    Kolbe, Michaela

    2011-01-01

    Spin polarization measurements of free electrons remain challenging since their first realization by Mott. The relevant quantity of a spin polarimeter is its figure of merit, FoM=S 2 I/I 0 , with the asymmetry function S and the ratio between scattered and primary intensity I/I 0 . State-of-the-art devices are based on single-channel scattering (spin-orbit or exchange interaction) which is characterized by FoM ≅10 -4 . On the other hand, modern hemispherical analyzers feature an efficient multichannel detection of spin-integral intensity with more than 10 4 data points simultaneously. In comparison between spin-resolved and spin-integral electron spectroscopy we are thus faced with a difference in counting efficiency by 8 orders of magnitude. The present work concentrates on the development and investigation of a novel technique for increasing the efficiency in spin-resolved electron spectroscopy by multichannel detection. The spin detector was integrated in a μ-metal shielded UHV-chamber and mounted behind a conventional hemispherical analyzer. The electrostatic lens system's geometry was determined by electron-optical simulations. The basic concept is the k parallel -conserving elastic scattering of the (0,0)-beam on a W(100) scattering crystal under 45 impact angle. It could be demonstrated that app. 960 data points (15 energy and 64 angular points) could be displayed simultaneously on a delayline detector in an energy interval of ≅3 eV. This leads to a two-dimensional figure of merit of FoM 2D =1.7. Compared to conventional spin detectors, the new type is thus characterized by a gain in efficiency of 4 orders of magnitude. The operational reliability of the new spin polarimeter could be proven by measurements with a Fe/MgO(100) and O p(1 x 1)/Fe(100)-sample, where results from the literature were reproduced with strongly decreased measuring time. Due to the high intensity it becomes possible, to investigate strongly reactive samples in a short time. This

  15. Medium energy measurements of N-N parameters

    International Nuclear Information System (INIS)

    Ambrose, D.; Bachman, M.; Coffey, P.; Glass, G.; Jobst, B.; McNaughton, K.H.; Nguyen, C.; Riley, P.J.

    1993-01-01

    The authors report here progress made during the three year period January 1, 1990, to December 31, 1993, for the Department of Energy Three-Year Grant No. DE-FG05-88ER40446, third year. A major part of the work has been associated with nucleon-nucleon (N-N) research carried out at the Nucleon Physics Laboratory (NPL) at the Los Alamos Meson Physics Facility (LAMPF). During this period they also completed data acquisition and analyses of a TRIUMF experiment, but they have no further plans for experimental work at TRIUMF. Other research has been and will be continued to be carried out at BNL, and involves two rare kaon decay experiments, BNL E791, now completed, and a second generation rare kaon decay experiment, E871, which has just this summer completed an engineering test run. The authors are now also members of a proposed experiment, STAR, (Solenoidal Tracker at RHIC) to be carried out at the Relativistic Heavy Ion Collider facility, RHIC, at BNL. The past three years have been a time of rapid change in the focus of the experimental program. A LAMPF experiment, E1097, in which they spent a large amount of effort during the past three years, was terminated due to funding shortages after they had fabricated the detector, but before data acquisition, and consequently they increased their participation in the rare kaon experiment at BNL, E871. It now appears that there will be no LAMPF N-N program after 1993, so that the research efforts will concentrate on the BNL rare kaon decay measurement, E871, and on STAR. The authors expect that STAR, which requires the fabrication of a large colliding beam detector facility, will use an increasing amount of their research efforts during the next few years. In what follows they describe recent progress on the LAMPF and TRIUMF N-N measurements, on the BNL rare kaon decay work, and on the initial work with the STAR group

  16. Detailed EXOSAT and optical observations of the intermediate polar 3A0729+103: discovery of two medium energy X-ray emission regions

    International Nuclear Information System (INIS)

    McHardy, I.M.; Pye, J.P.; Fairall, A.P.; Menzies, J.W.

    1987-01-01

    EXOSAT observations of the intermediate polar cataclysmic variable 3A0729+103 reveal a strong orbital modulation, with the 2-4KeV X-rays being significantly more modulated than the 4-6keV X-rays, indicative of photoelectric absorption. The 913 second modulation which is very prominent in the optical light curve, is weakly detected in the medium-energy X-ray light curve, confirming that it represents the white dwarf spin period. These observations are well explained by a combination of two sources of medium-energy X-ray emission. The presence of two emission regions is also clearly seen in the optical spectroscopy, particularly in the intensity of the He II4686 line which has two peaks during the orbit. The authors identify the two optical emission regions with the two X-ray emission regions. (author)

  17. Transport calculation of medium-energy protons and neutrons by Monte Carlo method

    International Nuclear Information System (INIS)

    Ban, Syuuichi; Hirayama, Hideo; Katoh, Kazuaki.

    1978-09-01

    A Monte Carlo transport code, ARIES, has been developed for protons and neutrons at medium energy (25 -- 500 MeV). Nuclear data provided by R.G. Alsmiller, Jr. were used for the calculation. To simulate the cascade development in the medium, each generation was represented by a single weighted particle and an average number of emitted particles was used as the weight. Neutron fluxes were stored by the collisions density method. The cutoff energy was set to 25 MeV. Neutrons below the cutoff were stored to be used as the source for the low energy neutron transport calculation upon the discrete ordinates method. Then transport calculations were performed for both low energy neutrons (thermal -- 25 MeV) and secondary gamma-rays. Energy spectra of emitted neutrons were calculated and compared with those of published experimental and calculated results. The agreement was good for the incident particles of energy between 100 and 500 MeV. (author)

  18. Energy-imbalance mechanism of domain wall motion induced by propagation spin waves in finite magnetic nanostripe

    International Nuclear Information System (INIS)

    Zhu, Jinrong; Han, Zhaoyan; Su, Yuanchang; Hu, Jingguo

    2014-01-01

    The mechanism of the domain wall (DW) motions induced by spin wave in finite magnetic nanostripe is studied by micromagnetic simulations. We find that the spin-wave induced DM motions are always accompanied by an energy imbalance between two sides of the DW. The DW motion can be attributed to the expansion of the low-energy-density area and the contraction of the high-energy-density area. The energy imbalance strongly depends on whether the spin wave passes through the DW or is reflected by the DW. In the area of the spin wave propagation, the energy density increases with the time. However, in the superposition area of the incident spin wave and the reflected spin wave, the energy density decreases with the increasing of the time. It shows that this energy imbalance can be controlled by tuning the frequency of the spin wave. Finally, the effect of the damping parameter value is discussed. - Highlights: • The mechanism of the spin-wave induced DW motions is studied. • The spin-wave induced DW motions and the energy imbalance mechanism are given. • The DW motion with the same direction to that of SW is explained. • The DW motion with the opposite direction to that of SW is explained

  19. High-spin research with HERA [High Energy-Resolution Array

    International Nuclear Information System (INIS)

    Diamond, R.M.

    1987-06-01

    The topic of this report is high spin research with the High Energy Resolution Array (HERA) at Lawrence Berkeley Laboratory. This is a 21 Ge detector system, the first with bismuth germanate (BGO) Compton suppression. The array is described briefly and some of the results obtained during the past year using this detector facility are discussed. Two types of studies are described: observation of superdeformation in the light Nd isotopes, and rotational damping at high spin and excitation energy in the continuum gamma ray spectrum

  20. Medium-term energy hub management subject to electricity price and wind uncertainty

    International Nuclear Information System (INIS)

    Najafi, Arsalan; Falaghi, Hamid; Contreras, Javier; Ramezani, Maryam

    2016-01-01

    Highlights: • A new model for medium-term energy hub management is proposed. • Risk aversion is considered in medium-term energy hub management. • Stochastic programing is used to solve the medium-term energy hub management problem. • Electricity price and wind uncertainty are considered. - Abstract: Energy hubs play an important role in implementing multi-carrier energy systems. More studies are required in both their modeling and operating aspects. In this regard, this paper attempts to develop medium-term management of an energy hub in restructured power systems. A model is presented to manage an energy hub which has electrical energy and natural gas as inputs and electrical and heat energy as outputs. Electricity is procured in various ways, either purchasing it from a pool-based market and bilateral contracts, or producing it from a Combined Heat and Power (CHP) unit, a diesel generator unit and Wind Turbine Generators (WTGs). Pool prices and wind turbine production are subject to uncertainty, which makes energy management a complex puzzle. Heat demand is also procured by a furnace and a CHP unit. Energy hub managers should make decisions whether to purchase electricity from the electricity market and gas from the gas network or to produce electricity using a set of generators to meet the electrical and heat demands in the presence of uncertainties. The energy management objective is to minimize the total cost subject to several technical constraints using stochastic programming. Conditional Value at Risk (CVaR), a well-known risk measure, is used to reduce the unfavorable risk of costs. In doing so, the proposed model is illustrated using a sample test case with actual prices, load and wind speed data. The results show that the minimum cost is obtained by the best decisions involving the electricity market and purchasing natural gas for gas facilities. Considering risk also increases the total expected cost and decreases the CVaR.

  1. Maximal Rashba-like spin splitting via kinetic-energy-coupled inversion-symmetry breaking

    Science.gov (United States)

    Sunko, Veronika; Rosner, H.; Kushwaha, P.; Khim, S.; Mazzola, F.; Bawden, L.; Clark, O. J.; Riley, J. M.; Kasinathan, D.; Haverkort, M. W.; Kim, T. K.; Hoesch, M.; Fujii, J.; Vobornik, I.; MacKenzie, A. P.; King, P. D. C.

    2017-09-01

    Engineering and enhancing the breaking of inversion symmetry in solids—that is, allowing electrons to differentiate between ‘up’ and ‘down’—is a key goal in condensed-matter physics and materials science because it can be used to stabilize states that are of fundamental interest and also have potential practical applications. Examples include improved ferroelectrics for memory devices and materials that host Majorana zero modes for quantum computing. Although inversion symmetry is naturally broken in several crystalline environments, such as at surfaces and interfaces, maximizing the influence of this effect on the electronic states of interest remains a challenge. Here we present a mechanism for realizing a much larger coupling of inversion-symmetry breaking to itinerant surface electrons than is typically achieved. The key element is a pronounced asymmetry of surface hopping energies—that is, a kinetic-energy-coupled inversion-symmetry breaking, the energy scale of which is a substantial fraction of the bandwidth. Using spin- and angle-resolved photoemission spectroscopy, we demonstrate that such a strong inversion-symmetry breaking, when combined with spin-orbit interactions, can mediate Rashba-like spin splittings that are much larger than would typically be expected. The energy scale of the inversion-symmetry breaking that we achieve is so large that the spin splitting in the CoO2- and RhO2-derived surface states of delafossite oxides becomes controlled by the full atomic spin-orbit coupling of the 3d and 4d transition metals, resulting in some of the largest known Rashba-like spin splittings. The core structural building blocks that facilitate the bandwidth-scaled inversion-symmetry breaking are common to numerous materials. Our findings therefore provide opportunities for creating spin-textured states and suggest routes to interfacial control of inversion-symmetry breaking in designer heterostructures of oxides and other material classes.

  2. Micromagnetism in (001) magnetite by spin-polarized low-energy electron microscopy

    International Nuclear Information System (INIS)

    Figuera, Juan de la; Vergara, Lucía; N'Diaye, Alpha T.; Quesada, Adrian; Schmid, Andreas K.

    2013-01-01

    Spin-polarized low-energy electron microscopy was used to image a magnetite crystal with (001) surface orientation. Sets of spin-dependent images of magnetic domain patterns observed in this surface were used to map the direction of the magnetization vector with high spatial and angular resolution. We find that domains are magnetized along the surface directions, and domain wall structures include 90° and 180° walls. A type of unusually curved domain walls are interpreted as Néel-capped surface terminations of 180° Bloch walls. - Highlights: ► The (001) surface of magnetite is imaged by spin-polarized low-energy electron microscopy. ► The magnetic domain microstructure is resolved. ► Magnetic easy axes in this surface are found to be along directions. ► Magnetic domain wall structures include wide Néel-caps

  3. Micromagnetism in (001) magnetite by spin-polarized low-energy electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Figuera, Juan de la, E-mail: juan.delafiguera@iqfr.csic.es [Instituto de Química-Física “Rocasolano”, CSIC, Madrid 28006 (Spain); Vergara, Lucía [Instituto de Química-Física “Rocasolano”, CSIC, Madrid 28006 (Spain); N' Diaye, Alpha T. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Quesada, Adrian [Instituto de Cerámica y Vidrio, CSIC, Calle Kelsen 5, 28049, Madrid (Spain); Schmid, Andreas K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2013-07-15

    Spin-polarized low-energy electron microscopy was used to image a magnetite crystal with (001) surface orientation. Sets of spin-dependent images of magnetic domain patterns observed in this surface were used to map the direction of the magnetization vector with high spatial and angular resolution. We find that domains are magnetized along the surface <110> directions, and domain wall structures include 90° and 180° walls. A type of unusually curved domain walls are interpreted as Néel-capped surface terminations of 180° Bloch walls. - Highlights: ► The (001) surface of magnetite is imaged by spin-polarized low-energy electron microscopy. ► The magnetic domain microstructure is resolved. ► Magnetic easy axes in this surface are found to be along <110> directions. ► Magnetic domain wall structures include wide Néel-caps.

  4. Fingerprints of single nuclear spin energy levels using STM - ENDOR.

    Science.gov (United States)

    Manassen, Yishay; Averbukh, Michael; Jbara, Moamen; Siebenhofer, Bernhard; Shnirman, Alexander; Horovitz, Baruch

    2018-04-01

    We performed STM-ENDOR experiments where the intensity of one of the hyperfine components detected in ESR-STM is recorded while an rf power is irradiated into the tunneling junction and its frequency is swept. When the latter frequency is near a nuclear transition a dip in ESR-STM signal is observed. This experiment was performed in three different systems: near surface SiC vacancies where the electron spin is coupled to a next nearest neighbor 29 Si nucleus; Cu deposited on Si(111)7x7 surface, where the unpaired electron of the Cu atom is coupled to the Cu nucleus ( 63 Cu, 65 Cu) and on Tempo molecules adsorbed on Au(111), where the unpaired electron is coupled to a Nitrogen nucleus ( 14 N). While some of the hyperfine values are unresolved in the ESR-STM data due to linewidth we find that they are accurately determined in the STM-ENDOR data including those from remote nuclei, which are not detected in the ESR-STM spectrum. Furthermore, STM-ENDOR can measure single nuclear Zeeman frequencies, distinguish between isotopes through their different nuclear magnetic moments and detect quadrupole spectra. We also develop and solve a Bloch type equation for the coupled electron-nuclear system that facilitates interpretation of the data. The improved spectral resolution of STM - ENDOR opens many possibilities for nanometric scale chemical analysis. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. High spin exotic states and new method for pairing energy

    International Nuclear Information System (INIS)

    Molique, H.

    1996-01-01

    We present a new method called 'PSY-MB', initially developed in the framework of abstract group theory for the solution of the problem of strongly interacting multi-fermionic systems with particular to systems in an external rotating field. The validity of the new method (PSY-MB) is tested on model Hamiltonians. A detailed comparison between the obtained solutions and the exact ones is performed. The new method is used in the study of realistic nuclear Hamiltonians based on the Woods-Saxon potential within the cranking approximation to study the influence of residual monopole pairing interactions in the rare-earth mass region. In parallel with this new technique we present original results obtained with the Woods-Saxon mean-field and the self-consistent Hartree-Fock approximation in order to investigate such exotic effects as octupole deformations and hexadecapole C 4 -polarizing deformations in the framework of high-spin physics. By developing these three approaches in one single work we prepare the ground for the nuclear structure calculations of the new generation - where the residual two-body interactions are taken into account also in the weak pairing limit. (author)

  6. EFFECTS OF SPIN ON HIGH-ENERGY RADIATION FROM ACCRETING BLACK HOLES

    Energy Technology Data Exchange (ETDEWEB)

    O’ Riordan, Michael; Pe’er, Asaf [Physics Department, University College Cork, Cork (Ireland); McKinney, Jonathan C., E-mail: michael_oriordan@umail.ucc.ie [Department of Physics and Joint Space-Science Institute, University of Maryland, College Park, MD 20742 (United States)

    2016-11-01

    Observations of jets in X-ray binaries show a correlation between radio power and black hole spin. This correlation, if confirmed, points toward the idea that relativistic jets may be powered by the rotational energy of black holes. In order to examine this further, we perform general relativistic radiative transport calculations on magnetically arrested accretion flows, which are known to produce powerful jets via the Blandford–Znajek (BZ) mechanism. We find that the X-ray and γ -ray emission strongly depend on spin and inclination angle. Surprisingly, the high-energy power does not show the same dependence on spin as the BZ jet power, but instead can be understood as a redshift effect. In particular, photons observed perpendicular to the spin axis suffer little net redshift until originating from close to the horizon. Such observers see deeper into the hot, dense, highly magnetized inner disk region. This effect is largest for rapidly rotating black holes due to a combination of frame dragging and decreasing horizon radius. While the X-ray emission is dominated by the near horizon region, the near-infrared (NIR) radiation originates at larger radii. Therefore, the ratio of X-ray to NIR power is an observational signature of black hole spin.

  7. Spin observables in inelastic proton-nucleus scattering at intermediate energy

    International Nuclear Information System (INIS)

    Smith, R.D.

    1984-01-01

    This dissertation is a study of spin observables in inelastic proton-nucleus reactions for incident proton energies near 1 GeV. At this energy, the dominant reaction mechanisms are (1) quasi-free knockout of one or more nucleons, and (2) pion production through the Δ resonance. The cross section due to quasi-free knockout can be reasonably well understood theoretically in a multiple scattering picture, which uses measured NN amplitudes as input. Calculations of this sort were carried out in reference [10] using scalar NN amplitudes parameterized as Gaussians. The author has extended this picture to include spin dependent NN amplitudes. This allows calculation of all the spin observables, Ay, DLL, DSS, DNN, DLS, and DSL, as well as the cross section dsigma/dOmegadp due to quasi-free knockout of one or more particles. The cross section and polarization Ay have been measured at the LAMPF High Resolution Spectrometer at T/sub L/ = 800 MeV on 12 C. The theoretical results agree well with the data in the quasi-free region. The results for the remaining spin observables provide predictions for experiments which can be performed at LAMPF. By comparing the calculations with the data, it may be possible to separate the contribution due to a quasi-free knockout, and see a signature of quasi-free Δ production in the spin observables

  8. Spin wave energy dispersion in KCuF/sub 3/: a nearly one-dimensional spin-1/2 antiferromagnet. [4. 7/sup 0/K

    Energy Technology Data Exchange (ETDEWEB)

    Hutchings, M T; Ikeda, H; Milne, J M

    1979-09-28

    Using inelastic neutron scattering techniques, the spin wave energy dispersion in the (010) plane of the distorted perovskite KCuF/sub 3/, which exhibits many magnetic properties of the spin-1/2 one-dimensional antiferromagnet, has been investigated at 4.7 K (T/sub N/ = 39 K). The measurements confirm the very strong exchange interaction between the spins in the (001) direction, and show that in this direction the expression for the excitation energies of the spin-1/2 antiferromagnetic chain given by J des Cloizeaux and J J Pearson is obeyed. The exchange interaction between these chains is found to be only 1.6% of that within the chains.

  9. Analysis of low and medium energy physics records in databases. Science and technology indicators in low and medium energy physics. With particular emphasis on nuclear data

    International Nuclear Information System (INIS)

    Hillebrand, C.D.

    1998-12-01

    An analysis of the literature on low and medium energy physics, with particular emphasis on nuclear data, was performed on the basis of the contents of the bibliographic database INIS (International Nuclear Information System). Quantitative data were obtained on various characteristics of relevant INIS records such as subject categories, language and country of publication, publication types, etc. Rather surprisingly, it was found that the number of records in nuclear physics has remained nearly constant over the last decade. The analysis opens up the possibility of further studies, e.g. on international research co-operation and on publication patterns. (author)

  10. Space-time picture of relativistic propagation of medium energy hadrons through nuclei

    International Nuclear Information System (INIS)

    Bleszynski, M.; Jaroszewicz, T.

    1985-01-01

    Relativistic virtual pair creation effects in hadron-nucleus scattering at medium energies are discussed. A close analogy is found between these effects (particle propagation backwards in time) and some of noneikonal correlations to the Glauber theory, arising from particle propagation backwards in space. In multiple scattering both effects appear only for configurations involving overlapping scatterers and lead to the non-additivity of phase shifts. The proper-time path-integral formalism is found to provide an intuitive geometrical picture of these phenomena. The relativistic corrections are estimated to be of the order k/(aE/sup 2/), k being the particle momentum, E its energy, and a the target size. At medium energies they are comparable to noneikonal corrections, of order 1/(ak). Both effects vanish at high energy, when particle propagation in space-time can be described by means of geometrical optics

  11. Energy dissipation during an explosion in a porous elasto-plastic medium

    Energy Technology Data Exchange (ETDEWEB)

    Lovetskii, E.E.; Maslennikov, A.M.; Fetisov, V.S.

    1979-01-01

    A study is made of the redistribution of energy from camouflage blasting in a saturated porous medium. The study is undertaken with the aid of a numerical solution to a system of hydrodynamic equations, that account for shear strength of the substance under investigation. A study is made of the energy characteristics of explosion, their dynamic development, the influence of strength parameters of the medium, and porosity on these characteristics. A mechanism that is associated with the impact compression of matter is identified as the basic mechanism of energy dissipation for dry porous media. Water saturation of pores brings the energy characteristics of the explosion close to the explosion in a monolith. 12 references, 5 figures, 1 table.

  12. Medium Btu gas from coal: a possible solution to the U. S. energy crisis

    Energy Technology Data Exchange (ETDEWEB)

    Taffe, P

    1978-03-03

    The future of coal gasification in the US, and in particular the potential of the Winkler process, are discussed. The economics and the efficiency of the Winkler process are considered. It is believed that medium Btu gas from coal is a better solution to the US energy crisis than is SNG made from coal.

  13. Medium-energy physics program. Progress report, February 1--April 1, 1976

    International Nuclear Information System (INIS)

    Dunn, E.

    1976-09-01

    A quarterly report on the medium-energy physics program at LAMPF is given. Topics covered include: (1) engineering support; (2) accelerator support; (3) accelerator systems development; (4) injector systems; (5) electronic instrumentation and computer systems; (6) accelerator operations; (7) experimental areas; (8) beam line development; (9) large-spectrometer systems; (10) research; (11) nuclear chemistry; (12) practical applications of LAMPF; and (13) management

  14. Medium-energy physics program. Progress report, August 1--October 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    van Dyck, O.B.; Dunn, E.D. (comps.)

    1978-05-01

    A report is given of the medium-energy physics program at the LAMPF linac for the period from August 1 through October 31, 1977. Topics discussed include: (1) accelerator facilities and development; (2) the main beam lines; (3) experimental areas; (4) research; (5) nuclear chemistry; (6) practical applications; (7) linac technology; and (8) management. (PMA)

  15. Medium-energy physics program. Progress report, August 1--October 31, 1977

    International Nuclear Information System (INIS)

    van Dyck, O.B.; Dunn, E.D.

    1978-05-01

    A report is given of the medium-energy physics program at the LAMPF linac for the period from August 1 through October 31, 1977. Topics discussed include: (1) accelerator facilities and development; (2) the main beam lines; (3) experimental areas; (4) research; (5) nuclear chemistry; (6) practical applications; (7) linac technology; and (8) management

  16. Performance of a Polarized Deuterium Internal Target in a Medium-Energy Electron Storage Ring.

    NARCIS (Netherlands)

    Zhou, Z.L.; Ferro Luzzi, M.M.E.; van den Brand, J.F.J.; Bulten, H.J.; Alarcon, R.; van Bommel, R.; Botto, T.; Bouwhuis, M.; Buchholz, M.; Choi, S.; Comfort, J.; Doets, M.; Dolfini, S.; Ent, R.; Gaulard, C.; de Jager, C.W.; Lang, J.; de Lange, D.J.; Miller, M.A.; Passchier, E.; Passchier, I.; Poolman, H.R.; Six, E.; Steijger, J.J.M.; Unal, O.; de Vries, H.

    1996-01-01

    A polarized deuterium target internal to a medium-energy electron storage ring is described in the context of spindependent (e, e′d) and (e ,e′p) experiments. Tensor polarized deuterium was produced in an atomic beam source and injected into a storage cell target. A Breit-Rabi polarimeter was used

  17. Experimental medium energy physics: Annual progress report June 1987--May 1988

    International Nuclear Information System (INIS)

    1988-01-01

    This report discusses progress in experimental medium energy physics at Carnegie Mellon University. Some of the topics covered are: search for the ξ(2230); hyperon-antihyperon production studies; relativistic proton-nucleus and heavy ion-nucleus collisions; H dibaryon physics; hypernuclear physics research; pion physics; H particle experiment design and development; and electron scattering

  18. Energy losses (gains) of massive coloured particles in stochastic colour medium

    International Nuclear Information System (INIS)

    Leonidov, A.; Rossijskaya Akademiya Nauk, Moscow

    1995-01-01

    The propagation of massive coloured particles in stochastic background chromoelectric field is studied using the semiclassical equations of motion. Depending on the nature of the stochastic background we obtain the formulae for the energy losses of heavy coloured projectile in nonperturbative hadronic medium and for the energy gains in the stochastic field present, e.g., in the turbulent plasma. The result appears to be significantly dependent on the form of the correlation function of stochastic external field. (orig.)

  19. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP CIRCUM-PAN-PACIFIC RIKEN SYMPOSIUM ON HIGH ENERGY SPIN PHYSICS, VOLUME 25

    Energy Technology Data Exchange (ETDEWEB)

    KUMANO,S.; SHIBATA,T.A.; YAZAKI,K.

    2000-06-28

    The Circum-Pan-Pacific Riken Symposium on High Energy Spin Physics was held at Oukouchi Memorial Hall in Riken from November 3 through 6, 1999. It was held as a joint meeting of the 2nd Circum-Pan-Pacific Symposium on High Energy Spin Physics and the 3rd of the series of Riken Symposia related to the RHIC-SPIN. The 1st Circum-Pan-Pacific Symposium on High Energy Spin Physics was held at Kobe in 1996 and the RHIC-SPIN Riken Symposia had been held every two years since 1995. As Prof. Ozaki mentioned in his talk at the beginning of this meeting, the RHIC was ready for the first beam, physics experiments scheduled in 2000, and the RHIC-SPIN would start in 2001. It was therefore considered to be very timely for the researchers in the field of high energy spin physics to get together, clarifying the present status of the field and discussing interesting and important topics as well as experimental subjects to be pursued. It is especially important for the success of the RHIC-SPIN project that the researchers in the neighboring countries surrounding the Pacific are actively involved in it. This is why the above two series were joined in this. symposium. The subjects discussed in the symposium include: Hard processes probing spin-structure functions, polarization mechanisms in high energy reactions, lattice studies of polarized structure functions, theoretical models for the nucleon and its spin structure, RHIC and RHIC-SPIN projects, results and future projects of existing experimental facilities. Totally 73 scientists participated in the symposium, 27 from abroad and 46 from Japan. it consisted of 13 main sessions, with 33 invited and contributed talks, and 4 discussion sessions covering recent experimental and theoretical developments and important topics in high energy spin physics and closely related fields.

  20. Energies and damping rates of elementary excitations in spin-1 Bose-Einstein-condensed gases

    International Nuclear Information System (INIS)

    Szirmai, Gergely; Szepfalusy, Peter; Kis-Szabo, Krisztian

    2003-01-01

    The finite temperature Green's function technique is used to calculate the energies and damping rates of the elementary excitations of homogeneous, dilute, spin-1 Bose gases below the Bose-Einstein condensation temperature in both the density and spin channels. For this purpose a self-consistent dynamical Hartree-Fock model is formulated, which takes into account the direct and exchange processes on equal footing by summing up certain classes of Feynman diagrams. The model is shown to satisfy the Goldstone theorem and to exhibit the hybridization of one-particle and collective excitations correctly. The results are applied to gases of 23 Na and 87 Rb atoms

  1. Unpolarised and spin-change collisions between He/sup +/ and H at low energies

    Energy Technology Data Exchange (ETDEWEB)

    Falcon, C; Opradolce, L [Instituto de Astronomia y Fisica del Espacio, Buenos Aires (Argentina); Piacentini, R D

    1978-09-14

    He/sup +/-H collisions are studied for energies lower than the electron excitation threshold. Unpolarised cross sections having resonances and values greater than 4000 a/sup 2//sub 0/ and spin-change cross sections showing high structures are obtained. Comparisons with the corresponding H-H collision cross sections are displayed. The sensitivity of the cross sections to the potential energy curves is discussed.

  2. Influence of primary fragment excitation energy and spin distributions on fission observables

    Science.gov (United States)

    Litaize, Olivier; Thulliez, Loïc; Serot, Olivier; Chebboubi, Abdelaziz; Tamagno, Pierre

    2018-03-01

    Fission observables in the case of 252Cf(sf) are investigated by exploring several models involved in the excitation energy sharing and spin-parity assignment between primary fission fragments. In a first step the parameters used in the FIFRELIN Monte Carlo code "reference route" are presented: two parameters for the mass dependent temperature ratio law and two constant spin cut-off parameters for light and heavy fragment groups respectively. These parameters determine the initial fragment entry zone in excitation energy and spin-parity (E*, Jπ). They are chosen to reproduce the light and heavy average prompt neutron multiplicities. When these target observables are achieved all other fission observables can be predicted. We show here the influence of input parameters on the saw-tooth curve and we discuss the influence of a mass and energy-dependent spin cut-off model on gamma-rays related fission observables. The part of the model involving level densities, neutron transmission coefficients or photon strength functions remains unchanged.

  3. Summary of the 8th international symposium on high energy spin physics

    International Nuclear Information System (INIS)

    Bunce, G.

    1988-01-01

    The series of conferences on high energy spin physics dates back to Argonne, 1974, and the first use of the polarized proton beam at the ZGS. This conference is unique in that it is concerned both with the technology of spin and with particle physics: particle physicists need to know what experiments might be possible and target/beam/source physicists want to know what their work will lead to, and get new ideas. In many cases, and I believe that this is central to the success of spin physics and of this conference series, these are the same people. This summary will have three basic parts: where we are now relative to Argonne in 1974; a discussion of new experiments and theory---there were many new and intriguing results presented here; and new ideas for polarized sources, beams, and targets which point toward an exciting future program of particle physics. 13 refs., 2 figs., 4 tabs

  4. Towards the improvement of spin-isospin properties in nuclear energy density functionals

    International Nuclear Information System (INIS)

    Roca-Maza, X.; Colò, G.; Liang, H. Z.; Sagawa, H.; Meng, J.; Ring, P.; Zhao, P. W.

    2016-01-01

    We address the problem of improving existing nuclear Energy Density Functionals (EDFs) in the spin-isospin channel. For that, we propose two different ways. The first one is to carefully take into account in the fitting protocol some of the key ground state properties for an accurate description of the most studied spin-isospin resonances: the Gamow-Teller Resonance (GTR) [1]. The second consists in providing a strategy to build local covariant EDF keeping the main features from their non-local counterparts [2]. The RHF model based on a Lagrangian where heavy mesons carry the nuclear effective interaction have been shown to be successful in the description of spin-isospin resonances [3]. (paper)

  5. Energy Efficiency Market Report 2013: Market Trends and Medium-Term Prospects

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    Energy efficiency has been referred to as a ''hidden fuel'', one that extends energy supplies, increases energy security, lowers carbon emissions and generally supports sustainable economic growth. Yet it is hiding in plain sight: in 2011, investments in the energy efficiency market globally were at a similar scale to those in renewable energy or fossil-fuel power generation. The Energy Efficiency Market Report provides a practical basis for understanding energy efficiency market activities, a review of the methodological and practical challenges associated with measuring the market and its components, and statistical analysis of energy efficiency and its impact on energy demand. It also highlights a specific technology sector in which there is significant energy efficiency market activity, in this instance appliances and ICT. The report presents a selection of country case studies that illustrate current energy efficiency markets in specific sectors, and how they may evolve in the medium term. The energy efficiency market is diffuse, varied and involves all energy-consuming sectors of the economy. A comprehensive overview of market activity is complicated by the challenges associated with quantifying the components of the market and the paucity of comparable reported data. This report underscores how vital high-quality and timely energy efficiency data is to understanding this market.

  6. MEGA - A next generation mission in Medium Energy Gamma-Ray Astronomy

    International Nuclear Information System (INIS)

    Kanbach, Gottfried

    2001-01-01

    A Medium Energy Gamma-Ray Astronomy (MEGA) detector is being developed and proposed for a small satellite mission. MEGA intends to improve the sensitivity at medium γ-ray energies (0.4-50 MeV) by at least an order of magnitude with respect to past instruments. Its large field of view will be especially important for the discovery of transient sources and for conducting all-sky surveys. Key science objectives for MEGA are the investigation of cosmic high-energy accelerators and of nucleosynthesis sites with γ-ray lines. The large-scale structure of the galactic and cosmic diffuse background is another important goal for this mission. MEGA records and images γ-ray events by completely tracking Compton and pair creation interactions in a stack of double sided Si-strip track detectors and 3-D resolving CsI calorimeters

  7. Angular distribution of scattered electron and medium energy electron spectroscopy for metals

    International Nuclear Information System (INIS)

    Oguri, Takeo; Ishioka, Hisamichi; Fukuda, Hisashi; Irako, Mitsuhiro

    1986-01-01

    The angular distribution (AD) of scattered electrons produced by medium energy incident electrons (E P = 50 ∼ 300 eV) from polycrystalline Ti, Fe, Ni, Cu and Au were obtained by the angle-resolved medium energy electron spectrometer. The AD of the energy loss peaks are similar figures to AD of the elastically reflected electron peaks. Therefore, the exchanged electrons produced by the knock-on collision between the incident electrons and those of metals without momentum transfer are observed as the energy loss spectra (ELS). This interpretation differs from the inconsequent interpretation by the dielectric theory or the interband transition. The information depth and penetration length are obtained from AD of the Auger electron peaks. The contribution of the surface to spectra is 3 % at the maximum for E P = 50 eV. The true secondary peaks representing the secondary electron emission spectroscopy (SES) are caused by the emissions of the energetic electrons (kT e ≥ 4 eV), and SES is the inversion of ELS. The established fundamental view is that the medium energy electron spectra represent the total bulk density of states. (author)

  8. Low energy recycling of ionic liquids via freeze crystallization during cellulose spinning

    DEFF Research Database (Denmark)

    Liu, Yanrong; Meyer, Anne S.; Nie, Yi

    2018-01-01

    recycling method. EmimAc + 12.5 wt% H2O and EmimDep + 4 wt% H2O were selected for a quantitative mass and energy analysis of the cellulose spinning and IL recycling process (the maximal initial H2O levels in the ILs + H2O mixtures for cellulose dissolution were determined experimentally). The energy......Dep recycling. We also show that compared to a classical Lyocell fiber production method using N-methylmorpholine-N-oxide (NMMO) as solvent, use of ILs is energy saving in itself. Hence, significantly less H2O is required in the cellulose spinning process with ILs than with NMMO, and in turn less H2O has...

  9. Experimental parameters for quantitative surface analysis by medium energy ion scattering, ch. 1

    International Nuclear Information System (INIS)

    Turkenburg, W.C.; Kersten, H.H.; Colenbrander, B.G.; Jongh, A.P. de; Saris, F.W.

    1976-01-01

    A new UHV chamber for surface and surface layer analysis by collision spectroscopy of backscattered ions at medium energies is described. Experimental parameters like energy, angular and depth resolution, crystal alignment and background pressure are discussed. Formulae based on the use of an electrostatic energy analyser show that the analysis can be quantitative. Effects of beam induced build-up of a hydro-carbon layer, sputter cleaning and creation of radiation damage have been investigated for Cu (110) and Ni (110). Detection sensitivity for Carbon, Oxygen and Sulfur on Cu and Ni has been found to be 0.2, 0.1 and 0.03 of a monolayer respectively

  10. BSRF-3B3 Medium Energy X-ray Beamline and Its Application for XAFS Research

    International Nuclear Information System (INIS)

    Ma Chenyan; Cui Mingqi; Zhou Kejin; Zhao Yidong; Tian Yulian; Wu Ziyu; Zheng Lei; Zhu Jie; Zhao Jia; Chen Kai; Sun Lijuan

    2007-01-01

    A new medium X-ray beamline 3B3 covering energy from 1.2 keV up to 6.0 keV was built at Beijing Synchrotron Radiation Facility (BSRF) in 2005. With perfect capability of high monochromaticity, good focus and low harmonics, it could be applied to study metrology, optic component characteristics and medium X-ray absorption spectroscopy (XAS). A simple XAFS apparatus has been set up and some measurements such as S, P, Cl, Ca, Al, Mg K-edge X-ray absorption fine structure (XAFS) in their compounds have also been carried out. The results show that it is feasible to do XAFS research at 3B3 beamline under present condition. The fabrication of a more delicate medium XAFS spectrometer is underway including transmission, fluorescence and electronic yield modes

  11. Spinning fluids in general relativity

    Science.gov (United States)

    Ray, J. R.; Smalley, L. L.

    1982-01-01

    General relativity field equations are employed to examine a continuous medium with internal spin. A variational principle formerly applied in the special relativity case is extended to the general relativity case, using a tetrad to express the spin density and the four-velocity of the fluid. An energy-momentum tensor is subsequently defined for a spinning fluid. The equations of motion of the fluid are suggested to be useful in analytical studies of galaxies, for anisotropic Bianchi universes, and for turbulent eddies.

  12. Dual Energy CT Angiography of Peripheral Arterial Disease: Feasibility of Using Lower Contrast Medium Volume.

    Directory of Open Access Journals (Sweden)

    Abdulrahman Almutairi

    Full Text Available One of the main drawbacks associated with Dual Energy Computed Tomography Angiography (DECTA is the risk of developing contrast medium-induced nephropathy (CIN. The aim of the present study was firstly, to design an optimal CT imaging protocol by determining the feasibility of using a reduced contrast medium volume in peripheral arterial DECTA, and secondly, to compare the results with those obtained from using routine contrast medium volume.Thirty four patients underwent DECTA for the diagnosis of peripheral arterial disease. They were randomly divided into two groups: Group 1 (routine contrast volume group with n = 17, injection rate 4-5 ml/s, and 1.5 ml/kg of contrast medium, and Group 2 ((low contrast volume group, with n = 17, injection rate 4-5ml/s, and contrast medium volume 0.75 ml/kg. A fast kilovoltage-switching 64-slice CT scanner in the dual-energy mode was employed for the study. A total of 6 datasets of monochromatic images at 50, 55, 60, 65, 70 and 75 keV levels were reconstructed with adaptive statistical iterative reconstruction (ASIR at 50%. A 4-point scale was the tool for qualitative analysis of results. The two groups were compared and assessed quantitatively for image quality on the basis of signal-to-noise ratio (SNR and contrast-to-noise-ratio (CNR. Radiation and contrast medium doses were also compared.The overall mean CT attenuation and mean noise for all lower extremity body parts was significantly lower for the low volume contrast group (p<0.001, and varied significantly between groups (p = 0.001, body parts (p<0.001 and keVs (p<0.001. The interaction between group body parts was significant with CT attenuation and CNR (p = 0.002 and 0.003 respectively, and marginally significant with SNR (p = 0.047, with minimal changes noticed between the two groups. Group 2 (low contrast volume group displayed the lowest image noise between 65 and 70 keV, recorded the highest SNR and CNR at 65 keV, and produced significantly lower

  13. Direct observation and theory of trajectory-dependent electronic energy losses in medium-energy ion scattering.

    Science.gov (United States)

    Hentz, A; Parkinson, G S; Quinn, P D; Muñoz-Márquez, M A; Woodruff, D P; Grande, P L; Schiwietz, G; Bailey, P; Noakes, T C Q

    2009-03-06

    The energy spectrum associated with scattering of 100 keV H+ ions from the outermost few atomic layers of Cu(111) in different scattering geometries provides direct evidence of trajectory-dependent electronic energy loss. Theoretical simulations, combining standard Monte Carlo calculations of the elastic scattering trajectories with coupled-channel calculations to describe inner-shell ionization and excitation as a function of impact parameter, reproduce the effects well and provide a means for far more complete analysis of medium-energy ion scattering data.

  14. Technical Support Document: Development of the Advanced Energy Design Guide for Medium to Big Box Retail Buildings - 50% Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Bonnema, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Leach, Matt [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pless, Shanti [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-06-05

    This Technical Support Document describes the process and methodology for the development of the Advanced Energy Design Guide for Medium to Big Box Retail Buildings: Achieving 50% Energy Savings Toward a Net Zero Energy Building (AEDG-MBBR) ASHRAE et al. (2011b). The AEDG-MBBR is intended to provide recommendations for achieving 50% whole-building energy savings in retail stores over levels achieved by following ANSI/ASHRAE/IESNA Standard 90.1-2004, Energy Standard for Buildings Except Low-Rise Residential Buildings (Standard 90.1-2004) (ASHRAE 2004b). The AEDG-MBBR was developed in collaboration with the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), the American Institute of Architects (AIA), the Illuminating Engineering Society of North America (IES), the U.S. Green Building Council (USGBC), and the U.S. Department of Energy.

  15. Technical Support Document: Development of the Advanced Energy Design Guide for Medium to Big Box Retail Buildings - 50% Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Bonnema, E.; Leach, M.; Pless, S.

    2013-06-01

    This Technical Support Document describes the process and methodology for the development of the Advanced Energy Design Guide for Medium to Big Box Retail Buildings: Achieving 50% Energy Savings Toward a Net Zero Energy Building (AEDG-MBBR) ASHRAE et al. (2011b). The AEDG-MBBR is intended to provide recommendations for achieving 50% whole-building energy savings in retail stores over levels achieved by following ANSI/ASHRAE/IESNA Standard 90.1-2004, Energy Standard for Buildings Except Low-Rise Residential Buildings (Standard 90.1-2004) (ASHRAE 2004b). The AEDG-MBBR was developed in collaboration with the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), the American Institute of Architects (AIA), the Illuminating Engineering Society of North America (IES), the U.S. Green Building Council (USGBC), and the U.S. Department of Energy.

  16. Theoretical studies in medium-energy nuclear and hadronic physics. [Indiana Univ. Nuclear Theory Center and Department of Physics

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, C J; Macfarlane, M H; Matsui, T; Serot, B D

    1993-01-01

    A proposal for theoretical nuclear physics research is made for the period April 1, 1993 through March 31, 1996. Research is proposed in the following areas: relativistic many-body theory of nuclei and nuclear matter, quasifree electroweak scattering and strange quarks in nuclei, dynamical effects in (e,e[prime]p) scattering at large momentum transfer, investigating the nucleon's parton sea with polarized leptoproduction, physics of ultrarelativistic nucleus[endash]nucleus collisions, QCD sum rules and hadronic properties, non-relativistic models of nuclear reactions, and spin and color correlations in a quark-exchange model of nuclear matter. Highlights of recent research, vitae of principal investigators, and lists of publications and invited talks are also given. Recent research dealt primarily with medium-energy nuclear physics, relativistic theories of nuclei and the nuclear response, the nuclear equation of state under extreme conditions, the dynamics of the quark[endash]gluon plasma in relativistic heavy-ion collisions, and theories of the nucleon[endash]nucleon force.

  17. Some topics concerning N--N and N--D experiments at medium energy

    International Nuclear Information System (INIS)

    Simmons, J.E.

    1975-01-01

    The status of recent proton-proton phase shift analyses is reviewed at medium energy with mention of the state of the n-p I = 0 analyses. Some conclusions are reached, including a recommendation for renewed theoretical effort to calculate absorption parameters for N--N scattering above 300 MeV in higher partial waves (l greater than or equal to 3). Recent experimental data are examined for p-p small angle scattering at 630 MeV and also near 500 MeV. Further small angle experiments on p-p and p-d scattering are deemed desirable. A brief discussion of recent n-p charge exchange experiments is given. Finally, the status of medium to high energy (100 to 2000 MeV) p-d elastic scattering is reviewed with emphasis on back angle scattering and the usefulness of p-d polarization measurements. (1 table, 12 figures, 94 references) (U.S.)

  18. Spin and energy evolution equations for a wide class of extended bodies

    International Nuclear Information System (INIS)

    Racine, Etienne

    2006-01-01

    We give a surface integral derivation of the leading-order evolution equations for the spin and energy of a relativistic body interacting with other bodies in the post-Newtonian expansion scheme. The bodies can be arbitrarily shaped and can be strongly self-gravitating. The effects of all mass and current multipoles are taken into account. As part of the computation one of the 2PN potentials parametrizing the metric is obtained. The formulae obtained here for spin and energy evolution coincide with those obtained by Damour, Soffel and Xu for the case of weakly self-gravitating bodies. By combining an Einstein-Infeld-Hoffman-type surface integral approach with multipolar expansions we extend the domain of validity of these evolution equations to a wide class of strongly self-gravitating bodies. This paper completes in a self-contained way a previous work by Racine and Flanagan on translational equations of motion for compact objects

  19. Medium energy hadron-nucleus scattering in the 1/N expansion formalism

    International Nuclear Information System (INIS)

    Kuyucak, S.; Morrison, I.

    1992-01-01

    The algebraic-eikonal approach to the medium energy hadron-nucleus scattering is generalized to arbitrary interactions and boson types using the 1/N expansion technique for the interacting boson model. The results are used in a comparative study of proton scattering from deformed nuclei in the sd and sdg boson models. The two models give almost identical results for a pure quadrupole interaction but widely differ when a hexadecapole interaction is included. 25 refs., 3 tabs., 7 figs

  20. Medium-energy physics program. Progress report, February 1--April 1, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, E. (comp.)

    1976-09-01

    A quarterly report on the medium-energy physics program at LAMPF is given. Topics covered include: (1) engineering support; (2) accelerator support; (3) accelerator systems development; (4) injector systems; (5) electronic instrumentation and computer systems; (6) accelerator operations; (7) experimental areas; (8) beam line development; (9) large-spectrometer systems; (10) research; (11) nuclear chemistry; (12) practical applications of LAMPF; and (13) management. (PMA)

  1. Absorbed dose determination in water in medium energy x-ray beam

    International Nuclear Information System (INIS)

    Nisevic, G.; Spasic-Jokic, V.

    1998-01-01

    Absorbed dose determination in water phantom in medium energy X-ray beam, according to IAEA recommendations is given. This method is applied on Radiotherapy department of Military Academy Hospital in Belgrade. Reference points of measurements are on depth of 5 cm and 2 cm as it recommended in ref. Experimental results are shown in aim to introduce new dosimetric concept based on air kerma calibration factor recommended for application in our radiotherapy centers (author)

  2. Free-energy analysis of spin models on hyperbolic lattice geometries.

    Science.gov (United States)

    Serina, Marcel; Genzor, Jozef; Lee, Yoju; Gendiar, Andrej

    2016-04-01

    We investigate relations between spatial properties of the free energy and the radius of Gaussian curvature of the underlying curved lattice geometries. For this purpose we derive recurrence relations for the analysis of the free energy normalized per lattice site of various multistate spin models in the thermal equilibrium on distinct non-Euclidean surface lattices of the infinite sizes. Whereas the free energy is calculated numerically by means of the corner transfer matrix renormalization group algorithm, the radius of curvature has an analytic expression. Two tasks are considered in this work. First, we search for such a lattice geometry, which minimizes the free energy per site. We conjecture that the only Euclidean flat geometry results in the minimal free energy per site regardless of the spin model. Second, the relations among the free energy, the radius of curvature, and the phase transition temperatures are analyzed. We found out that both the free energy and the phase transition temperature inherit the structure of the lattice geometry and asymptotically approach the profile of the Gaussian radius of curvature. This achievement opens new perspectives in the AdS-CFT correspondence theories.

  3. Study of transitional Erbium nuclei (N=86) at very high spin. Highlight of dipolar transitions and medium livetimes in the continuum

    International Nuclear Information System (INIS)

    Bogaert, G.

    1984-01-01

    Average lifetimes and multipolarities of unresolved transitions deexciting very high spin states of the light Rare Earth nuclei (N approximately 86) have been determined by a measure of Doppler shift attenuation and their anisotropy. The spin selection is provided by the total energy spectrometer technique; great care was taken of the existence of many long lived isomeric states in the studied nuclei. The N approximately 86 nuclei have been formed in the 84 Kr(340 MeV) + 74 Ge → 158 Er* reactions using the 84 Kr beam of the Orsay ALICE facilities and targets of 74 Ge built at the PARIS Isotope separator of the CSNSM. NaI γ spectra have been thoroughly cleared of the discrete lines contribution through a carefull subtraction procedure synthetising NaI spectra from the Ge ones. At very high spin the continuum γ rays feed two well separated bumps with Esub(γ) approximately .65 MeV and Esub(γ) approximately 1.3 MeV. The 1.3 MeV transitions appear at I > 30 h and their energy does not vary with the increasing spin like expected in the rotational case of the well deformed nuclei; they are strongly collectively enhanced with B(E2) > 130 W.u. Below 1 MeV the anisotropy of transitions is R approximately 0.7, indicating their stretched dipole nature. Recent calculations of nuclear shape deformation (following Strutinsky shell correction method) reproduce the two bumps shape of the experimental spectra and the origin of the excitation is explained in terms of nuclear vibration (γ-vibration, wobbling motion) [fr

  4. The primary exposure standard of ENEA for medium energy X-ray: characteristics and measurements procedures

    International Nuclear Information System (INIS)

    Laitano, R.F.; Toni, M.P.

    1983-01-01

    A description is given of a medium energy X-ray free-air chamber used, as primary exposure standard, at the Laboratorio di Metrologia delle Radiazioni Ionizzanti of the Enea in Italy. The main features of an X-ray facility for the production of radiation between 40 KeV and 400 KeV are also described. The measurements procedures are then analyzed with respect to the realization of the exposure unit in the relevant energy range. Finally the results of some international comparisons are reported

  5. Anomalous resonance-radiation energy-transfer rate in a scattering dispersive medium

    International Nuclear Information System (INIS)

    Shekhtman, V.L.

    1992-01-01

    This paper describes a generalization of the concept of group velocity as an energy-transfer rate in a dispersive medium with complex refractive index when the polaritons, which are energy carriers, undergo scattering, in contrast to the classical concept of the group velocity of free polaritons (i.e., without scattering in the medium). The concept of delay time from quantum multichannel-scattering, theory is used as the fundamental concept. Based on Maxwell's equations and the new mathematical Φ-function method, a consistent conceptual definition of group velocity in terms of the ratio of the coherent-energy flux density to the coherent-energy density is obtained for the first time, and a critical analysis of the earlier (Brillouin) understanding of energy-transfer rate is given in the light of radiation-trapping theory and the quantum theory of resonance scattering. The role of generalized group velocity is examined for the interpretation of the phenomenon of multiple resonance scattering, or radiation diffusion. The question of causality for the given problem is touched upon; a new relationship is obtained, called the microcausality condition, which limits the anomalous values of group velocity by way of the indeterminacy principle and the relativistic causality principle for macroscopic time intervals directly measurable in experiment, whereby attention is focused on the connection of the given microcausality condition and the well-known Wigner inequality for the time delay of spherical waves. 22 refs

  6. Energy levels and electron g-factor of spherical quantum dots with Rashba spin-orbit interaction

    International Nuclear Information System (INIS)

    Vaseghi, B.; Rezaei, G.; Malian, M.

    2011-01-01

    We have studied simultaneous effects of Rashba spin-orbit interaction and external electric and magnetic fields on the subbands energy levels and electron g-factor of spherical quantum dots. It is shown that energy eigenvalues strongly depend on the combined effects of external electric and magnetic fields and spin-orbit interaction strength. The more the spin-orbit interaction strength increase, the more the energy eigenvalues increase. Also, we found that the electron g-factor sensitively differers from the bulk value due to the confinement effects. Furthermore, external fields and spin-orbit interaction have a great influence on this important quantity. -- Highlights: → Energy of spherical quantum dots depends on the spin-orbit interaction strength in external electric and magnetic fields. → Spin-orbit interaction shifts the energy levels. → Electron g-factor differs from the bulk value in spherical quantum dots due to the confinement effects. → Electron g-factor strongly depends on the spin-orbit interaction strength in external electric and magnetic fields.

  7. Examples from P2 and energy assessments at small to medium size manufacturers

    International Nuclear Information System (INIS)

    Fleischman, M.; Watters, J.C.; Cobourn, W.G.; Collins, D.J.

    1996-01-01

    Using engineering student-faculty teams, the U.S. Department of energy sponsored industrial assessment center (IAC) at the university of louisville does free pollution prevention and energy assessments at small to medium size manufacturers (SIC 20-39) in kentucky and indiana. Each client plant must meet three of the following four criteria: Annual energy bills less than $1, 750, 000 and more than $50, 00. Gross annual sales of less than $75 million. Less than 500 employees. Lack a dedicated energy/waste engineer. Lack of in-house staff to perform these analyses. The program criteria and assessment procedures are briefly described and summaries of assessment at a sheet fed offset (lithographic) printing plant and 2 denim jeans pre washing plants are presented. 4 figs., 8 tabs

  8. Development of a Telescope for Medium-Energy Gamma-ray Astronomy

    Science.gov (United States)

    Sunter, Stan

    2012-01-01

    Since the launch of AGILE and FERMI, the scientific progress in high-energy (Eg greater than approximately 200 MeV) gamma-ray science has been, and will continue to be dramatic. Both of these telescopes cover a broad energy range from approximately 20 MeV to greater than 10 GeV. However, neither instrument is optimized for observations below approximately 200 MeV where many astrophysical objects exhibit unique, transitory behavior, such as spectral breaks, bursts, and flares. Hence, while significant progress from current observations is expected, there will nonetheless remain a significant sensitivity gap in the medium-energy (approximately 0.1-200 MeV) regime; the lower end of this range remains largely unexplored whereas the upper end will allow comparison with FERMI data. Tapping into this unexplored regime requires significant improvements in sensitivity. A major emphasis of modern detector development, with the goal of providing significant improvements in sensitivity in the medium-energy regime, focuses on high-resolution electron tracking. The Three-Dimensional Track Imager (3-DTI) technology being developed at GSFC provides high resolution tracking of the electron-positron pair from gamma-ray interactions from 5 to 200 MeV. The 3-DTI consists of a time projection chamber (TPC) and 2-D cross-strip microwell detector (MWD). The low-density and homogeneous design of the 3-DTI, offers unprecedented sensitivity by providing angular resolution near the kinematic limit. Electron tracking also enables measurement of gamma-ray polarization, a new tool to study astrophysical phenomenon. We describe the design, fabrication, and performance of a 30x30x30 cm3 3-DTI detector prototype of a medium-energy gamma-ray telescope.

  9. High-energy hadron spin-flip amplitude at small momentum transfer and new AN data from RHIC

    International Nuclear Information System (INIS)

    Cudell, J.-R.; Selyugin, O.V.; Predazzi, E.

    2004-01-01

    In the case of elastic high-energy hadron-hadron scattering, the impact of the large-distance contributions on the behaviour of the slopes of the spin-non-flip and of the spin-flip amplitudes is analysed. It is shown that the long tail of the hadronic potential in impact parameter space leads to a value of the slope of the reduced spin-flip amplitude larger than that of the spin-non-flip amplitude. This effect is taken into account in the calculation of the analysing power in proton-nucleus reactions at high energies. It is shown that the preliminary measurement of A N for p 12 C obtained by the E950 Collaboration indeed favours a spin-flip amplitude with a large slope. Predictions for A N at p L =250/ GeV/c are given. (orig.)

  10. Overview of spin physics

    International Nuclear Information System (INIS)

    Yokosawa, A.

    1992-01-01

    Spin physics activities at medium and high energies became significantly active when polarized targets and polarized beams became accessible for hadron-hadron scattering experiments. My overview of spin physics will be inclined to the study of strong interaction using facilities at Argonne ZGS, Brookhaven AGS (including RHIC), CERN, Fermilab, LAMPF, an SATURNE. In 1960 accelerator physicists had already been convinced that the ZGS could be unique in accelerating a polarized beam; polarized beams were being accelerated through linear accelerators elsewhere at that time. However, there was much concern about going ahead with the construction of a polarized beam because (i) the source intensity was not high enough to accelerate in the accelerator, (ii) the use of the accelerator would be limited to only polarized-beam physics, that is, proton-proton interaction, and (iii) p-p elastic scattering was not the most popular topic in high-energy physics. In fact, within spin physics, π-nucleon physics looked attractive, since the determination of spin and parity of possible πp resonances attracted much attention. To proceed we needed more data beside total cross sections and elastic differential cross sections; measurements of polarization and other parameters were urgently needed. Polarization measurements had traditionally been performed by analyzing the spin of recoil protons. The drawbacks of this technique are: (i) it involves double scattering, resulting in poor accuracy of the data, and (ii) a carbon analyzer can only be used for a limited region of energy

  11. Green marketing - How to put an environmental spin on your energy product, service, program or project

    International Nuclear Information System (INIS)

    Flynn, J.

    1992-01-01

    This paper examines how some smart marketers have quickly picked up on the new consumer interest in protecting the environment, turned it into increased sales and profits and at the same time effectively increased energy conservation. They asked their product developers to improve the environmental benefits of their existing products and to design some new ones. Then they asked their advertising writers to put an environmental spin on their product advertising. Next they made frequent visits to the bank with the increased sales revenues from an expanding market share and at the same time are doing something worthwhile in energy and environmental conservation

  12. Intercomparison of medium-energy neutron attenuation in iron and concrete

    International Nuclear Information System (INIS)

    Hirayama, H.

    1999-01-01

    Neutron attenuation of medium energy below 1 GeV has not been well understood until now. It is desired to obtain common agreements concerning the behaviours of neutrons inside various materials. This is necessary in order to agree on definitions of the attenuation length, which is very important for shielding calculations involving high energy accelerators. As one attempt, it was proposed by Japanese attendants of SATIF-2 to compare the attenuation of medium-energy neutrons inside iron and concrete shields between various computer codes and data, and was cited as a suitable action for SATIF. The first results from three groups were presented at SATIF-3. It has become clear that neutrons above 20 MeV are important for understanding the attenuation inside materials and that the geometry, planar or spherical, does not affect the results very much. Considering the CPU times required for Monte Carlo calculations and this result, revised problems to be calculated were prepared by the Japanese Working Group and sent to the participants of this action. The geometry is only plane, and calculations are required only for neutrons above 20 MeV. The secondary neutrons from high energy protons, which were calculated by H. Nakashima, are also included in the problem. The results from four groups were sent to the organizer at the end of August. This paper presents a comparison between groups concerning the attenuation length together with the neutron spectrum and the future themes which come from this intercomparison. (author)

  13. Statistical calculation of complete events in medium-energy nuclear collisions

    International Nuclear Information System (INIS)

    Randrup, J.

    1984-01-01

    Several heavy-ion accelerators throughout the world are presently able to deliver beams of heavy nuclei with kinetic energies in the range from tens to hundreds of MeV per nucleon, the so-called medium or intermediate energy range. At such energies a large number of final channels are open, each consisting of many nuclear fragments. The disassembly of the collision system is expected to be a very complicated process and a detailed dynamical description is beyond their present capability. However, by virtue of the complexity of the process, statistical considerations may be useful. A statistical description of the disassembly yields the least biased expectations about the outcome of a collision process and provides a meaningful reference against which more specific dynamical models, as well as the data, can be discussed. This lecture presents the essential tools for formulating a statistical model for the nuclear disassembly process. The authors consider the quick disassembly (explosion) of a hot nuclear system, a so-called source, into multifragment final states, which complete according to their statistical weight. First some useful notation is introduced. Then the expressions for exclusive and inclusive distributions are given and the factorization of an exclusive distribution into inclusive ones is carried out. In turn, the grand canonical approximation for one-fragment inclusive distributions is introduced. Finally, it is outlined how to generate a statistical sample of complete final states. On this basis, a model for statistical simulation of complete events in medium-energy nuclear collisions has been developed

  14. Probing medium-induced jet splitting and energy loss in heavy-ion collisions

    Science.gov (United States)

    Chang, Ning-Bo; Cao, Shanshan; Qin, Guang-You

    2018-06-01

    The nuclear modification of jet splitting in relativistic heavy-ion collisions at RHIC and the LHC energies is studied based on the higher twist formalism. Assuming coherent energy loss for the two splitted subjets, a non-monotonic jet energy dependence is found for the nuclear modification of jet splitting function: strongest modification at intermediate jet energies whereas weaker modification for larger or smaller jet energies. Combined with the smaller size and lower density of the QGP medium at RHIC than at the LHC, this helps to understand the groomed jet measurements from CMS and STAR Collaborations: strong modification of the momentum sharing zg distribution at the LHC and no obvious modification of zg distribution at RHIC. In addition, the observed nuclear modification pattern of the groomed jet zg distribution cannot be explained solely by independent energy loss of the two subjets. Our result may be tested in future measurements of groomed jets with lower jet energies at the LHC and larger jet energies at RHIC, for different angular separations between the two subjets.

  15. A stochastic security approach to energy and spinning reserve scheduling considering demand response program

    International Nuclear Information System (INIS)

    Partovi, Farzad; Nikzad, Mehdi; Mozafari, Babak; Ranjbar, Ali Mohamad

    2011-01-01

    In this paper a new algorithm for allocating energy and determining the optimum amount of network active power reserve capacity and the share of generating units and demand side contribution in providing reserve capacity requirements for day-ahead market is presented. In the proposed method, the optimum amount of reserve requirement is determined based on network security set by operator. In this regard, Expected Load Not Supplied (ELNS) is used to evaluate system security in each hour. The proposed method has been implemented over the IEEE 24-bus test system and the results are compared with a deterministic security approach, which considers certain and fixed amount of reserve capacity in each hour. This comparison is done from economic and technical points of view. The promising results show the effectiveness of the proposed model which is formulated as mixed integer linear programming (MILP) and solved by GAMS software. -- Highlights: → Determination of optimal spinning reserve capacity requirement in order to satisfy desired security level set by system operator based on stochastic approach. → Scheduling energy and spinning reserve markets simultaneously. → Comparing the stochastic approach with deterministic approach to determine the advantages and disadvantages of each. → Examine the effect of demand response participation in reserve market to provide spinning reserve.

  16. Orbital rotation without orbital angular momentum: mechanical action of the spin part of the internal energy flow in light beams

    DEFF Research Database (Denmark)

    Angelsky, O. V.; Bekshaev, A. Ya; Maksimyak, P. P.

    2012-01-01

    flow upon tight focusing of the beam, usually applied for energy flow detection by means of the mechanical action upon probe particles. We propose a two-beam interference technique that results in an appreciable level of spin flow in moderately focused beams and detection of the orbital motion of probe...... particles within a field where the transverse energy circulation is associated exclusively with the spin flow. This result can be treated as the first demonstration of mechanical action of the spin flow of a light field....

  17. Förster resonance energy transfer between acridinediones and selected fluorophores—Medium dependence

    Energy Technology Data Exchange (ETDEWEB)

    Krishnaveni, R. [National Centre for Ultrafast Processes, University of Madras, Taramani Campus, Chennai-600113 (India); Ramamurthy, P., E-mail: prm60@hotmail.com [National Centre for Ultrafast Processes, University of Madras, Taramani Campus, Chennai-600113 (India)

    2013-06-15

    We report highly efficient Förster resonance energy transfer process between acridinedione dyes and basic fluorophores. FRET between free and β-cyclodextrin modified acridinediones as donors and fluorophoric dyes like safranine as acceptor were investigated in an alcoholic medium, polymer solution and a polymeric film. Efficiency of the processes were experimentally found by steady-state and time-resolved experiments for different donor and acceptor combinations. The associated spectral parameters viz., R{sup 0}, J(λ) were calculated, the Stern–Volmer relations based on fluorescence intensity and lifetime were constructed and the rates of energy transfer were calculated. The results indicated that the dominant mechanism responsible for the excitation energy transfer is that of resonance transfer due to long range dipole–dipole interaction and the process was found to be highly efficient when the medium was a constrained one as in the case of a polymeric film. A multifold enhancement in efficiency of energy transfer was also observed when the donor was a modified acridinedione when compared to a free acridinedione. The reason is attributed to the effective binding of the acceptor into the cavity of β-cyclodextrin. Highlights: ► FRET between acridinediones and fluorophoric acceptors were investigated. ► FRET analysis was carried out in methanol, a 5% PVA solution and in PVA matrix. ► FRET efficiency was maximum when the medium was PVA matrix. ► FRET efficiency was also more when β-CD modified ADR is used as the donor. ► Efficiency enhancement is due to the inclusion of acceptor into the cavity of β-CD.

  18. Energy levels of a spin-orbit-coupled Bose-Einstein condensate in a double-well potential

    Science.gov (United States)

    Wang, Wen-Yuan; Cao, Hui; Zhu, Shi-Liang; Liu, Jie; Fu, Li-Bin

    2015-02-01

    We investigate the energy levels of a spin-orbit-coupled Bose-Einstein condensate in a double-well potential under the mean-field approximation. We find that the energy levels of the system can be significantly influenced by the atomic interactions. Without atomic interaction, four energy levels change linearly with the tunneling amplitude, the Raman coupling, and the spin-orbit coupling. However, whenever atomic interaction is considered, three more energy levels will appear, which have a nonlinear dependence on those parameters above. These three energy levels are multi-degenerate and related to the macro-symmetry of the system.

  19. Renormalized Stress-Energy Tensor of an Evaporating Spinning Black Hole.

    Science.gov (United States)

    Levi, Adam; Eilon, Ehud; Ori, Amos; van de Meent, Maarten

    2017-04-07

    We provide the first calculation of the renormalized stress-energy tensor (RSET) of a quantum field in Kerr spacetime (describing a stationary spinning black hole). More specifically, we employ a recently developed mode-sum regularization method to compute the RSET of a minimally coupled massless scalar field in the Unruh vacuum state, the quantum state corresponding to an evaporating black hole. The computation is done here for the case a=0.7M, using two different variants of the method: t splitting and φ splitting, yielding good agreement between the two (in the domain where both are applicable). We briefly discuss possible implications of the results for computing semiclassical corrections to certain quantities, and also for simulating dynamical evaporation of a spinning black hole.

  20. Spin assignments of nuclear levels above the neutron binding energy in $^{88}$Sr

    CERN Multimedia

    Neutron resonances reveal nuclear levels in the highly excited region of the nucleus around the neutron binding energy. Nuclear level density models are therefore usually calibrated to the number of observed levels in neutron-induced reactions. The gamma-ray cascade from the decay of the highly excited compound nucleus state to the ground state show dierences dependent on the initial spin. This results in a dierence in the multiplicity distribution which can be exploited. We propose to use the 4${\\pi}$ total absorption calorimeter (TAC) at the n TOF facility to determine the spins of resonances formed by neutrons incident on a metallic $^{87}$Sr sample by measuring the gamma multiplicity distributions for the resolved resonances. In addition we would like to use the available enriched $^{87}$Sr target for cross section measurements with the C$\\scriptscriptstyle{6}$D$\\scriptscriptstyle{6}$ detector setup.

  1. Spin and energy transfer between magnetic ions and free carriers in diluted-magnetic semiconductor heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Yakovlev, D.R. [Experimental Physics 2, University of Dortmund, 44227 Dortmund (Germany); Ioffe Physico-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation); Kneip, M.; Bayer, M. [Experimental Physics 2, University of Dortmund, 44227 Dortmund (Germany); Maksimov, A.A.; Tartakovskii, I.I. [Institute of Solid State Physics, Russian Academy of Sciences, 142432 Chernogolovka (Russian Federation); Keller, D.; Ossau, W.; Molenkamp, L.W. [Physikalisches Institut der Universitaet Wuerzburg, 97074 Wuerzburg (Germany); Scherbakov, A.V.; Akimov, A.V. [Ioffe Physico-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation); Waag, A. [Abteilung Halbleiterphysik, Universitaet Ulm, 89081 Ulm (Germany)

    2004-03-01

    In this paper we give a brief overview of our studies on dynamical processes in diluted-magnetic-semiconductor heterostructures based on (Zn,Mn)Se and (Cd,Mn)Te. Presence of free carriers is an important factor which determines the energy- and spin transfer in a coupled systems of magnetic ions, lattice (the phonon system) and carriers. We report also new data on dynamical response of magnetic ions interacting with photogenerated electron-hole plasma. (Zn,Mn)Se/(Zn,Be)Se structures with relatively high Mn content of 11% provide spin-lattice relaxation time of about 20 ns, which is considerably shorter then the characteristic times of nonequilibrium phonons ranging to 1 {mu}s. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Effect of gas filling pressure and operation energy on ion and neutron emission in a medium energy plasma focus device

    Science.gov (United States)

    Niranjan, Ram; Rout, R. K.; Srivastava, Rohit; Kaushik, T. C.

    2018-03-01

    The effects of gas filling pressure and operation energy on deuterium ions and neutrons have been studied in a medium energy plasma focus device, MEPF-12. The deuterium gas filling pressure was varied from 1 to 10 mbar at an operation energy of 9.7 kJ. Also, the operation energy was varied from 3.9 to 9.7 kJ at a deuterium gas filling pressure of 4 mbar. Time resolved emission of deuterium ions was measured using a Faraday cup. Simultaneously, time integrated and time resolved emissions of neutrons were measured using a silver activation detector and plastic scintillator detector, respectively. Various characteristics (fluence, peak density, and most probable energy) of deuterium ions were estimated using the Faraday cup signal. The fluence was found to be nearly independent of the gas filling pressure and operation energy, but the peak density and most probable energy of deuterium ions were found to be varying. The neutron yield was observed to be varying with the gas filling pressure and operation energy. The effect of ions on neutrons emission was observed at each operation condition.

  3. Proceedings of the meeting on few-body problems in high and medium energy physics

    International Nuclear Information System (INIS)

    Yukawa, T.

    1985-12-01

    The study meeting on few-body problems in high and medium energy physics was held from October 3 to 5, 1985, at National Laboratory for High Energy Physics. Two meetings were held already concerning few body physics, but most of the participants were theorists. In this meeting, high priority was put on the attendance of experimental physicists. As a bridge between particle and nuclear physics, the few body physics in an intermediate energy region has become important recently. The topics in this meeting were meson spectroscopy, baryonium, kaon physics, muonic fusion, dibaryon, φNN system, quarks and skyrmions, NN correlation, and symmetry test in few-body system. The gists of the papers presented are collected in this book. (Kako, I.)

  4. Analysis of Humid Air Turbine Cycle with Low- or Medium-Temperature Solar Energy

    International Nuclear Information System (INIS)

    Hongbin Zhao, H.; Yue, P.; Cao, L.

    2009-01-01

    A new humid air turbine cycle that uses low- or medium-temperature solar energy as assistant heat source was proposed for increasing the mass flow rate of humid air. Based on the combination of the first and second laws of thermodynamics, this paper described and compared the performances of the conventional and the solar HAT cycles. The effects of some parameters such as pressure ratio, turbine inlet temperature (TIT), and solar collector efficiency on humidity, specific work, cycle's exergy efficiency, and solar energy to electricity efficiency were discussed in detail. Compared with the conventional HAT cycle, because of the increased humid air mass flow rate in the new system, the humidity and the specific work of the new system were increased. Meanwhile, the solar energy to electricity efficiency was greatly improved. Additionally, the exergy losses of components in the system under the given conditions were also studied and analyzed.

  5. Progress in the development of global medium-energy nucleon-nucleus optical model potentials

    International Nuclear Information System (INIS)

    Madland, D.G.

    1997-01-01

    Two existing global medium-energy nucleon-nucleus phenomenological optical model potentials are described and compared with experiment and with each other. The first of these employs a Dirac approach (second-order reduction) that is global in projectile energy and projectile isospin and applies to the target nucleus 208 Pb. The second of these employs a relativistic equivalent to the Schroedinger equation (including relativistic kinematics) that is global in projectile energy, projectile isospin, and target (Z,A). Finally, current work is described and the influence of the nuclear bound state problem (treated in relativistic mean field theory) on the Dirac scattering problem is mentioned. Spherical target nuclei are treated in the present work and strongly-collective target nuclei (rotational and vibrational) requiring coupled-channels approaches will be treated in a future paper. (author)

  6. Cosmic ray acceleration by shock waves in a diffusion medium. Research of high energies

    International Nuclear Information System (INIS)

    Lagage, P.O.

    1982-06-01

    The problem of galactic cosmic-ray acceleration is presented with the study of a new acceleration mechanism by supernova shock waves in a diffusive medium. The question is: do supernova shocks have enough time to accelerate cosmic rays beyond 10 4 -10 5 GeV. A firm upper limit to the energy that can be acquired by particles is established and it is considered that the mean free path of the particle has its lowest possible value and the most favorable model of supernova evolution. The diffusion coefficients which are relevant for the determination of the high energy cut off are investigated. The effect of the spatial dependence of the diffusion coefficient on the rate of acceleration of particles is examined. A more realistic cut off energy is calculated. We find E max = 2 10 4 GeV [fr

  7. Analysis of Humid Air Turbine Cycle with Low- or Medium-Temperature Solar Energy

    Directory of Open Access Journals (Sweden)

    Hongbin Zhao

    2009-01-01

    Full Text Available A new humid air turbine cycle that uses low- or medium-temperature solar energy as assistant heat source was proposed for increasing the mass flow rate of humid air. Based on the combination of the first and second laws of thermodynamics, this paper described and compared the performances of the conventional and the solar HAT cycles. The effects of some parameters such as pressure ratio, turbine inlet temperature (TIT, and sollar collector efficiency on humidity, specific work, cycle's exergy efficiency, and solar energy to electricity efficiency were discussed in detail. Compared with the conventional HAT cycle, because of the increased humid air mass flow rate in the new system, the humidity and the specific work of the new system were increased. Meanwhile, the solar energy to electricity efficiency was greatly improved. Additionally, the exergy losses of components in the system under the given conditions were also studied and analyzed.

  8. MCNP6 Simulation of Light and Medium Nuclei Fragmentation at Intermediate Energies

    Energy Technology Data Exchange (ETDEWEB)

    Mashnik, Stepan Georgievich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kerby, Leslie Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of Idaho, Moscow, ID (United States)

    2015-08-24

    Fragmentation reactions induced on light and medium nuclei by protons and light nuclei of energies around 1 GeV/nucleon and below are studied with the Los Alamos transport code MCNP6 and with its CEM03.03 and LAQGSM03.03 event generators. CEM and LAQGSM assume that intermediate-energy fragmentation reactions on light nuclei occur generally in two stages. The first stage is the intranuclear cascade (INC), followed by the second, Fermi breakup disintegration of light excited residual nuclei produced after the INC. CEM and LAQGSM account also for coalescence of light fragments (complex particles) up to sup>4He from energetic nucleons emitted during INC. We investigate the validity and performance of MCNP6, CEM, and LAQGSM in simulating fragmentation reactions at intermediate energies and discuss possible ways of further improving these codes.

  9. Barriers to energy efficiency improvement. Empirical evidence from small-and-medium-sized enterprises in China

    Energy Technology Data Exchange (ETDEWEB)

    Kostka, Genia; Moslener, Ulf; Andreas, Jan G.

    2012-07-01

    This paper analyzes barriers for energy efficiency investments for small-and medium-sized enterprises (SMEs) in China. Based on a survey of 480 SMEs in Zhejiang Province, this study assesses financial, informational, and organizational barriers for energy efficiency investments in the SME sector. The conventional view has been that the lack of appropriate financing mechanisms particularly hinders SMEs to adopt cost-effective energy efficiency measures. As such, closing the financing gap for SMEs is seen as a prerequisite in order to promote energy efficiency in the sector. The econometric estimates of this study, however, suggest that access to information is an important determinant of investment outcomes, while this is less clear with respect to financial and organizational factors. More than 40 percent of enterprises in the sample declared that that they are not aware of energy saving equipments or practices in their respective business area, indicating that there are high transaction costs for SMEs to gather, assess, and apply information about energy saving potentials and relevant technologies. One implication is that the Chinese government may assume an active role in fostering the dissemination of energy-efficiency related information in the SME sector. (orig.)

  10. Energy spectrum, the spin polarization, and the optical selection rules of the Kronig-Penney superlattice model with spin-orbit coupling

    Science.gov (United States)

    Li, Rui

    2018-02-01

    The Kronig-Penney model, an exactly solvable one-dimensional model of crystal in solid physics, shows how the allowed and forbidden bands are formed in solids. In this paper, we study this model in the presence of both strong spin-orbit coupling and the Zeeman field. We analytically obtain four transcendental equations that represent an implicit relation between the energy and the Bloch wave vector. Solving these four transcendental equations, we obtain the spin-orbital bands exactly. In addition to the usual band gap opened at the boundary of the Brillouin zone, a much larger spin-orbital band gap is also opened at some special sites inside the Brillouin zone. The x component of the spin-polarization vector is an even function of the Bloch wave vector, while the z component of the spin-polarization vector is an odd function of the Bloch wave vector. At the band edges, the optical transition rates between adjacent bands are nonzero.

  11. The angular dependence of spin-state energy splittings in the ? core

    Science.gov (United States)

    Groß, Lynn; Steenbock, Torben; Herrmann, Carmen

    2013-07-01

    Spin-state energy splittings are highly relevant for catalysis, molecular magnetism, and materials science, yet continue to pose a challenge for electronic structure methods. For a Fe2O2+ 2 core, we evaluate the bridging angle dependence of energy splittings between ferromagnetically and antiferromagnetically coupled states for different exchange-correlation functionals, and compare with complete active space self-consistent field (CASSCF) values, also including second-order perturbative corrections (CASPT2). CASSCF and CASPT2 yield strong antiferromagnetic coupling, with the smallest coupling at 100°, and a smooth dependence on the angle for Fe-O-Fe angles of 70° to 120°. Interestingly, this is qualitatively the same behaviour as often found for stable dinuclear transition metal complexes. While all functionals show the same angular dependence as CASPT2, they favour the antiferromagnetic state less strongly. Pure functionals such as BP86, BLYP, SSB-D, and TPSS come closer to the CASPT2 results (with energy splittings by about 60 kJ/mol smaller than the CASPT2 ones) than hybrid functionals. The hybrid functionals B3LYP, B3LYP⋆, and PBE0 favour the antiferromagnetic state even less strongly, resulting in ferromagnetic coupling for angles around 100°. The good qualitative agreement between CASPT2 and CASSCF on the one hand and CASPT2 and density functional theory on the other hand for angles between 70° and 110° suggests that the chosen active space of 18 electrons in 14 orbitals may be adequate for spin-state energy splitting of Fe2O2+ 2 in that region (possibly due to error cancellation), while angles of 60° or 120° may require larger active spaces. This study is complemented by an analysis of local spins, local charges, and CASSCF natural orbitals.

  12. Computer simulation program for medium-energy ion scattering and Rutherford backscattering spectrometry

    Science.gov (United States)

    Nishimura, Tomoaki

    2016-03-01

    A computer simulation program for ion scattering and its graphical user interface (MEISwin) has been developed. Using this program, researchers have analyzed medium-energy ion scattering and Rutherford backscattering spectrometry at Ritsumeikan University since 1998, and at Rutgers University since 2007. The main features of the program are as follows: (1) stopping power can be chosen from five datasets spanning several decades (from 1977 to 2011), (2) straggling can be chosen from two datasets, (3) spectral shape can be selected as Gaussian or exponentially modified Gaussian, (4) scattering cross sections can be selected as Coulomb or screened, (5) simulations adopt the resonant elastic scattering cross section of 16O(4He, 4He)16O, (6) pileup simulation for RBS spectra is supported, (7) natural and specific isotope abundances are supported, and (8) the charge fraction can be chosen from three patterns (fixed, energy-dependent, and ion fraction with charge-exchange parameters for medium-energy ion scattering). This study demonstrates and discusses the simulations and their results.

  13. Computer simulation program for medium-energy ion scattering and Rutherford backscattering spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tomoaki, E-mail: t-nishi@hosei.ac.jp

    2016-03-15

    A computer simulation program for ion scattering and its graphical user interface (MEISwin) has been developed. Using this program, researchers have analyzed medium-energy ion scattering and Rutherford backscattering spectrometry at Ritsumeikan University since 1998, and at Rutgers University since 2007. The main features of the program are as follows: (1) stopping power can be chosen from five datasets spanning several decades (from 1977 to 2011), (2) straggling can be chosen from two datasets, (3) spectral shape can be selected as Gaussian or exponentially modified Gaussian, (4) scattering cross sections can be selected as Coulomb or screened, (5) simulations adopt the resonant elastic scattering cross section of {sup 16}O({sup 4}He, {sup 4}He){sup 16}O, (6) pileup simulation for RBS spectra is supported, (7) natural and specific isotope abundances are supported, and (8) the charge fraction can be chosen from three patterns (fixed, energy-dependent, and ion fraction with charge-exchange parameters for medium-energy ion scattering). This study demonstrates and discusses the simulations and their results.

  14. Positronium spin conversion during collisions with Xe and its application for measuring the kinetic energy

    International Nuclear Information System (INIS)

    Shibuya, Kengo; Kawamura, Yoshihiro; Saito, Haruo

    2015-01-01

    Positronium(Ps) can undergo ortho-para spin conversion reaction during Ps-Xecollisions due to spin-orbit interaction. We have investigated energy dependence of this reaction rate and found it is nearly proportional to T 2.1 , where T is the temperature (300-623 K), while the pick-off annihilation rate is proportional to T. The strong temperature dependence of the former annihilation rate is attributed to a nature of p-wave scattering because this reaction is forbidden in s-wave scattering. In addition, a new method for measuring Ps kinetic energy has been developed with a high resolution and a high sensitivity by utilizing the strong temperature dependence as a 'thermometer.' Analyzingthe obtained time evolution of Ps kinetic energy, we have determined the momentum transfer cross section during Ps-Xecollisions at a very low energy (40-60 meV) to be 12(2)×10 −16 cm 2 . (paper)

  15. Development strategy of green energy industry for Taipei—A modern medium-sized city

    International Nuclear Information System (INIS)

    Lu, Shyi-Min; Huang, May-Yao; Su, Pu-Ti; Tseng, Kuo-Tung; Chen, Falin

    2013-01-01

    Taipei, a subtropical modern medium city, is essentially featured with high population density, scarce land, and large traffic flow. Moreover, there are abundant green energy resources reserved in Taipei. If they were fully developed, there would be 13,040 GWh electricity generated per year, resulting in a total of 9.37 million tons of carbon dioxide emissions abatement. The development of the green energy industry in this city not only can bring significant energy-saving and carbon-reducing benefits, but also may create huge derivative business opportunities. For example, the total output values of the solar PV and electric vehicles industries would be as high as 700 billion yuan. In this study, through Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis, we concluded that the top priorities for Taipei for the development of green energy industries are building energy conservation and electrified transportation, specifically, the following four items: electric vehicles, Light-Emitting Diode (LED) lighting, inverter air conditioning, and Energy Service Company (ESCO). Meanwhile, Taipei is a domestic and international key of politics, transportation, technology, commerce, and finance. Taipei is very likely to become an internationalized green energy industrial hub, achieving the “3E” goals of economic prosperousness, environmental protection, and energy security. -- Highlights: •Building energy conservation and electrified transportation are top priorities. •SWOT analysis applied to systematically conclude four green energy industrial items for Taipei. •Specifically, electric vehicles, LED lighting, inverter air conditioning, and ESCO. •13,040 GWh electricity would be generated per year from Taipei's rich renewables. •The derivative business opportunities would exceed 700 billion yuan

  16. Structural characterization of CdSe/ZnS quantum dots using medium energy ion scattering

    Science.gov (United States)

    Sortica, M. A.; Grande, P. L.; Radtke, C.; Almeida, L. G.; Debastiani, R.; Dias, J. F.; Hentz, A.

    2012-07-01

    In the present work, we have analyzed CdSe/ZnS core-shell quantum dots by medium energy ion scattering (MEIS), which is a powerful technique to explore the synthesis, formation, stability, and elemental distribution of such core-shell structures, along with other auxiliary analytical techniques. By comparing different quantum-dot structural models spectra with the experimental MEIS data, we were able to obtain some sample structural information. We found that, despite the well known non stoichiometric Cd:Se ratio, the core is stoichiometric, and there is an excess of cadmium distributed in the shell.

  17. Unique electron polarimeter analyzing power comparison and precision spin-based energy measurement

    International Nuclear Information System (INIS)

    Joseph Grames; Charles Sinclair; Joseph Mitchell; Eugene Chudakov; Howard Fenker; Arne Freyberger; Douglas Higinbotham; Poelker, B.; Michael Steigerwald; Michael Tiefenback; Christian Cavata; Stephanie Escoffier; Frederic Marie; Thierry Pussieux; Pascal Vernin; Samuel Danagoulian; Kahanawita Dharmawardane; Renee Fatemi; Kyungseon Joo; Markus Zeier; Viktor Gorbenko; Rakhsha Nasseripour; Brian Raue; Riad Suleiman; Benedikt Zihlmann

    2004-01-01

    Precision measurements of the relative analyzing powers of five electron beam polarimeters, based on Compton, Moller, and Mott scattering, have been performed using the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). A Wien filter in the 100 keV beamline of the injector was used to vary the electron spin orientation exiting the injector. High statistical precision measurements of the scattering asymmetry as a function of the spin orientation were made with each polarimeter. Since each polarimeter receives beam with the same magnitude of polarization, these asymmetry measurements permit a high statistical precision comparison of the relative analyzing powers of the five polarimeters. This is the first time a precise comparison of the analyzing powers of Compton, Moller, and Mott scattering polarimeters has been made. Statistically significant disagreements among the values of the beam polarization calculated from the asymmetry measurements made with each polarimeter reveal either errors in the values of the analyzing power, or failure to correctly include all systematic effects. The measurements reported here represent a first step toward understanding the systematic effects of these electron polarimeters. Such studies are necessary to realize high absolute accuracy (ca. 1%) electron polarization measurements, as required for some parity violation measurements planned at Jefferson Laboratory. Finally, a comparison of the value of the spin orientation exiting the injector that provides maximum longitudinal polarization in each experimental hall leads to an independent and very precise (better than 10-4) absolute measurement of the final electron beam energy

  18. Low Energy Spectrum of Proximate Kitaev Spin Liquid α -RuCl3 by Terahertz Spectroscopy

    Science.gov (United States)

    Little, Arielle; Wu, Liang; Kelley, Paige; Banerjee, Arnab; Bridges, Craig; Yan, Jiaqiang; Nagler, Stephen; Mandrus, David; Orenstein, Joseph

    A Quantum Spin Liquid (QSL) is an ultra-quantum state of matter with no ordered ground state. Recently, a route to a QSL identified by Kitaev has received a great deal of attention. The compound α -RuCl3, in which Ru atoms form a honeycomb lattice, has been shown to possess Kitaev exchange interactions, although a smaller Heisenberg interaction exists and leads to a zig-zag antiferromagnetic state below 7 K. Because of proximity to the exactly-solvable Kitaev spin-liquid model, this material is considered a potential host for Majorana-like modes. In this work, we use time-domain terahertz (THz) Spectroscopy to probe the low-energy excitations of α -RuCl3. We observe the emergence of a sharp magnetic spin-wave absorption peak below the AFM ordering temperature at 7 K on top of a broad continuum that persists up to room temperature. Additionally we report the polarization dependence of the THz absorption, which reveals optical birefringence, indicating the presence of large monoclinic domains.

  19. Spin-isospin excitations induced by heavy ions at Saturne energies

    International Nuclear Information System (INIS)

    Hennino, T.

    1989-01-01

    Our program on the Spin-Isospin excitations started with the ( 3 He, 3 H) and ( 2 H, 2 He) reactions was extended with the heavy ion beams available at Saturne ( 12 C, 16 0, 20 Ne and 40 Ar) to study systematically the Δ excitation energy region. Projectile-ejectile dependences were measured. The Δ peak shift appears as a common feature in all charge exchange reactions. The first cross section calculations for the ( 12 C, 12 N) reaction are in good quantitative agreement with the data [fr

  20. Interplay between bulk medium evolution and (D)GLV energy loss

    International Nuclear Information System (INIS)

    Molnar, Denes; Sun, Deke

    2014-01-01

    We study the consistency between high-p T nuclear suppression (R AA ) and elliptic flow (v 2 ) using Gyulassy–Levai–Vitev (GLV) energy loss or a simpler power-law dE/dL formula, for a variety of bulk evolution models. The results generally confirm our earlier work [1] that found suppressed elliptic flow for transversely expanding media. One exception is the set of hydrodynamic solutions used recently [2] by Betz and Gyulassy, which give significantly higher v 2 but unfortunately assume unrealistic bag-model equation of state. On the other hand, we show that covariant treatment of energy loss introduces an interplay between jet direction and hydrodynamic flow of the medium, which largely counteracts elliptic flow suppression caused by transverse expansion

  1. Ion-induced particle desorption in time-of-flight medium energy ion scattering

    Science.gov (United States)

    Lohmann, S.; Primetzhofer, D.

    2018-05-01

    Secondary ions emitted from solids upon ion impact are studied in a time-of-flight medium energy ion scattering (ToF-MEIS) set-up. In order to investigate characteristics of the emission processes and to evaluate the potential for surface and thin film analysis, experiments employing TiN and Al samples were conducted. The ejected ions exhibit a low initial kinetic energy of a few eV, thus, requiring a sufficiently high acceleration voltage for detection. Molecular and atomic ions of different charge states originating both from surface contaminations and the sample material are found, and relative yields of several species were determined. Experimental evidence that points towards a predominantly electronic sputtering process is presented. For emitted Ti target atoms an additional nuclear sputtering component is suggested.

  2. Very High Specific Energy, Medium Power Li/CFx Primary Battery for Launchers and Space Probes

    Science.gov (United States)

    Brochard, Paul; Godillot, Gerome; Peres, Jean Paul; Corbin, Julien; Espinosa, Amaya

    2014-08-01

    Benchmark with existing technologies shows the advantages of the lithium-fluorinated carbon (Li/CFx) technology for use aboard future launchers in terms of a low Total Cost of Ownership (TCO), especially for high energy demanding missions such as re-ignitable upper stages for long GTO+ missions and probes for deep space exploration.This paper presents the new results obtained on this chemistry in terms of electrical and climatic performances, abuse tests and life tests. Studies - co-financed between CNES and Saft - looked at a pure CFx version with a specific energy up to 500 Wh/kg along with a medium power of 80 to 100 W/kg.

  3. CsI electromagnetic calorimeter development for a low or medium energy e+e- collider

    International Nuclear Information System (INIS)

    King, M.E.

    1993-10-01

    Design considerations for an electromagnetic Csl calorimeter suitable for use at low and medium energy, high-luminosity e + e - storage rings are presented, together with results of a test of an array of Csl(Tl) crystals in an e - /π - beam (120 to 400 MeV) at TRIUMF. The crystal array used in the test was designed to explore longitudinal and transverse crystal segmentation, and a redundant wavelength-shifter and photodiode readout system. Energy resolution of (1.69 ± 0.08)%/√E and (1.83 ± 0.05)%/√E was obtained for two different crystal tower configurations. Position resolution of 6.5 (9.0) mm was obtained at 300 (120)MeV for four 4x4 cm 2 , 4 rl. Csl crystals

  4. Charge-equilibrium and radiation of low-energy cosmic rays passing through interstellar medium

    Science.gov (United States)

    Rule, D. W.; Omidvar, K.

    1977-01-01

    The charge equilibrium and radiation of an oxygen and an iron beam in the MeV per nucleon energy range, representing a typical beam of low-energy cosmic rays passing through the interstellar medium, is considered. Electron loss of the beam has been taken into account by means of the First Born approximation allowing for the target atom to remain unexcited, or to be excited to all possible states. Electron capture cross sections have been calculated by means of the scaled Oppenheimer-Brinkman-Kramers approximation, taking into account all atomic shells of the target atoms. Radiation of the beam due to electron capture into the excited states of the ion, collisional excitation and collisional inner-shell ionization of the ions has been considered. Effective X-ray production cross sections and multiplicities for the most energetic X-ray lines emitted by the Fe and O beams have been calculated.

  5. Prototyping of beam position monitor for medium energy beam transport section of RAON heavy ion accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hyojae, E-mail: lkcom@ibs.re.kr; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)

    2016-02-15

    A heavy ion accelerator, RAON is going to be built by Rare Isotope Science Project in Korea. Its target is to accelerate various stable ions such as uranium, proton, and xenon from electron cyclotron resonance ion source and some rare isotopes from isotope separation on-line. The beam shaping, charge selection, and modulation should be applied to the ions from these ion sources because RAON adopts a superconducting linear accelerator structure for beam acceleration. For such treatment, low energy beam transport, radio frequency quadrupole, and medium energy beam transport (MEBT) will be installed in injector part of RAON accelerator. Recently, development of a prototype of stripline beam position monitor (BPM) to measure the position of ion beams in MEBT section is under way. In this presentation, design of stripline, electromagnetic (EM) simulation results, and RF measurement test results obtained from the prototyped BPM will be described.

  6. Probes for the development of medium deep geothermal energy; Sonden zur Erschliessung der mitteltiefen Geothermie

    Energy Technology Data Exchange (ETDEWEB)

    Stuckmann, Uwe; Gottschalk, Daniel [REHAU AG und Co., Rehau (Germany)

    2011-10-24

    Compared to the near-surface geothermal energy, higher temperatures can be developed in the medium-depth geothermal energy (400 to 1,000 meters). Thus, the efficiency of geothermal power plants can be increased. The significantly higher yield performance and extraction performance are opposite to the higher costs of installation. At high thermal gradients of the surface one may completely dispense with the heat pump and directly heat. Geothermal probes at the current state of the art are reaching the limits of its applicability. Only newly developed geothermal probes offer a pressure resistance and temperature resistance in order to exploit these deeper regions. Such projects will be accompanied by the mining authority according to the power of approval. Extensive financial supports are available with the market incentive program of the Federal Government. Thus, the use of geothermal probes is possible in deeper regions. The feasibility and cost of future projects will be affected positively.

  7. ρ-meson self-energy and dielectron emissivity in an isospin-asymmetric pion medium

    International Nuclear Information System (INIS)

    Titov, A.I.; Gulamov, T.I.; Kaempfer, B.

    1996-01-01

    The ρ-meson self-energy in an isospin-asymmetric pion gas at finite temperature and charged-pion chemical potential is evaluated. We utilize a conventional effective π-ρ Lagrangian and the functional integral representation of the partition function in the second order in the ρππ coupling constant. We analyze the ρ-meson polarization operator and its dependence on the invariant mass M and spatial momentum parallel p parallel of the ρ meson. The pole positions and the values of the imaginary parts of the self-energy for different polarization states have different functional dependences on M and parallel p parallel. The corresponding dielectron rate (calculated from the imaginary part of the in-medium ρ-meson propagator) shows a distinctive asymmetry when the momentum t=p + -p - is perpendicular or parallel to p, where p ± are the e ± momenta of the electron pair. copyright 1996 The American Physical Society

  8. Final Report: Medium Energy Measurements of N-N Parameters, April 1, 1994 - September 30, 1996

    International Nuclear Information System (INIS)

    Ambrose, David; Betts, Wayne; Coffey, Patrick; Glass, George; McDonough, James; Riley, Peter; Tang, Jaw-Luen

    1998-01-01

    Our research program had four main thrusts, only one of which can be considered as measurements of N-N parameters: (1) Finishing the data analyses associated with recent LAMPF and TRIUMPF N-N experiments, whose overall purpose has been the determination of the nucleon-nucleon amplitudes, both for isospin 0 and 1 at medium energies; (2) continuing work on BNL E871, a search for rare decay modes of the KL; (3) work on the RHIC-STAR project, an experiment to create and study a quark gluon plasma and nuclear matter at high energy density; (4) beginning a new AGS experiment (E896) which will search for the lowest mass state of the predicted strange di-baryons, the Ho, and other exotic states of nuclear matter through nucleus-nucleus collisions

  9. Near-field thermal upconversion and energy transfer through a Kerr medium.

    Science.gov (United States)

    Khandekar, Chinmay; Rodriguez, Alejandro W

    2017-09-18

    We present an approach for achieving large Kerr χ (3) -mediated thermal energy transfer at the nanoscale that exploits a general coupled-mode description of triply resonant, four-wave mixing processes. We analyze the efficiency of thermal upconversion and energy transfer from mid- to near-infrared wavelengths in planar geometries involving two slabs supporting far-apart surface plasmon polaritons and separated by a nonlinear χ (3) medium that is irradiated by externally incident light. We study multiple geometric and material configurations and different classes of intervening mediums-either bulk or nanostructured lattices of nanoparticles embedded in nonlinear materials-designed to resonantly enhance the interaction of the incident light with thermal slab resonances. We find that even when the entire system is in thermodynamic equilibrium (at room temperature) and under typical drive intensities ~ W/μm 2 , the resulting upconversion rates can approach and even exceed thermal flux rates achieved in typical symmetric and non-equilibrium configurations of vacuum-separated slabs. The proposed nonlinear scheme could potentially be exploited to achieve thermal cooling and refrigeration at the nanoscale, and to actively control heat transfer between materials with dramatically different resonant responses.

  10. Experimental investigation of a novel indirect solar dryer implementing PCM as energy storage medium

    Energy Technology Data Exchange (ETDEWEB)

    Shalaby, S.M., E-mail: saleh_shalaby@yahoo.com; Bek, M. A.

    2014-07-01

    Highlights: • The performance of a novel indirect solar dryer is investigated experimentally. • PCM, paraffin wax, is used as energy storage medium. • The novel ISD is suitable for drying medical plants. • Ocimum and Thevetia are dried at their prescribed drying temperatures. • The novel design maintains the desired temperature for 7 consecutive h/day. - Abstract: A novel indirect solar dryer (ISD) design using phase change material (PCM) as energy storage medium was experimentally investigated. The system consists of two identical solar air heaters, drying compartment, PCM storage units and a blower. The ISD was tested under no load with and without PCM at a wide range of mass flow rates (0.0664–0.2182 kg/s). It is found that after using the PCM, the temperature of the drying air is higher than ambient temperature by 2.5–7.5 °C after sunset for five hours at least. In addition, the mass flow rates of 0.1204 and 0.0894 kg/s give the peak values of the drying temperature when the ISD is operated with and without PCM, respectively. The novel design successfully maintains the desired temperature for seven consecutive hours every day. This helps reaching the final moisture content of Ocimum Basilicum and Thevetia Neriifolia after 12 and 18 h, respectively.

  11. A program in medium-energy nuclear physics. Progress report, January 1, 1992--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Berman, B.L.; Dhuga, K.S.

    1994-08-01

    This renewal proposal requests continued funding for our program in experimental medium-energy nuclear physics. The focus of our program remains the understanding of the short-range part of the strong interaction in the nuclear medium. In the past three years we have focused our attention ever more sharply on experiments with real tagged photons at CEBAF. We are part of the Hall-B Collaboration at CEBAF. We are co-spokespersons on two approved CEBAF experiments, Photoreactions on {sup 3}He and Photoabsorption and Photofission of Nuclei, and we are preparing another, Nondiffractive Photoproduction of the {rho} Meson with Linearly Polarized Photons, for presentation to the next CEBAF PAC. We are part of the team that is instrumenting the Photon Tagger and a high-energy tagged polarized-photon beam for Hall B; some of the instrumentation for these projects is being built at our Nuclear Detector Laboratory, under the auspices of The George Washington University Center for Nuclear Studies. Our recent measurements of pion scattering from {sup 3}H and {sup 3}He at LAMPF and of cluster knockout from few-body nuclei at NIKHEF have yielded very provocative results, showing the importance of the very light nuclei as a laboratory for quantifying important aspects of the nuclear many-body force. We look forward to expanding our studies of short-range forces in nuclei, particularly the very fight nuclei using electromagnetic probes and employing the extraordinary power of CEBAF and the CLAS.

  12. A program in medium-energy nuclear physics. Renewal proposal and progress report August 1, 1994

    International Nuclear Information System (INIS)

    Berman, B.L.; Dhuga, K.S.

    1994-01-01

    This renewal proposal requests continued funding for our program in experimental medium-energy nuclear physics. The focus of our program remains the understanding of the short-range part of the strong interaction in the nuclear medium. In the past three years we have focused our attention ever more sharply on experiments with real tagged photons at CEBAF. We are part of the Hall-B Collaboration at CEBAF. We are co-spokespersons on two approved CEBAF experiments, Photoreactions on 3 He and Photoabsorption and Photofission of Nuclei, and we are preparing another, Nondiffractive Photoproduction of the ρ Meson with Linearly Polarized Photons, for presentation to the next CEBAF PAC. We are part of the team that is instrumenting the Photon Tagger and a high-energy tagged polarized-photon beam for Hall B; some of the instrumentation for these projects is being built at our Nuclear Detector Laboratory, under the auspices of The George Washington University Center for Nuclear Studies. Our recent measurements of pion scattering from 3 H and 3 He at LAMPF and of cluster knockout from few-body nuclei at NIKHEF have yielded very provocative results, showing the importance of the very light nuclei as a laboratory for quantifying important aspects of the nuclear many-body force. We look forward to expanding our studies of short-range forces in nuclei, particularly the very fight nuclei using electromagnetic probes and employing the extraordinary power of CEBAF and the CLAS

  13. Energy and exergy analyses of medium temperature latent heat thermal storage with high porosity metal matrix

    International Nuclear Information System (INIS)

    Kumar, Ashish; Saha, Sandip K.

    2016-01-01

    Graphical abstract: I. Metal matrix is used as the thermal conductivity enhancers (TCE) in PCM-based TES. II. Time evolution second law analysis is evaluated for different porosities and pore diameters. III. Reduction in fluctuation in HTF temperature is significantly affected by the change in porosity (ε) shown in figure. IV. Maximum energy and exergy efficiencies are obtained for porosity of 0.85. V. Effect of pore diameter on first law and second law efficiencies is found to be marginal. - Abstract: Thermal energy storage system in a concentrating solar plant (CSP) reduces the gap between energy demand and supply caused by the intermittent behaviour of solar radiation. In this paper, detailed exergy and energy analyses of shell and tube type latent heat thermal storage system (LHTES) for medium temperature solar thermal power plant (∼200 °C) are performed to estimate the net useful energy during the charging and discharging period in a cycle. A commercial-grade organic phase change material (PCM) is stored inside the annular space of the shell and the heat transfer fluid (HTF) flows through the tubes. Thermal conductivity enhancer (TCE) in the form of metal matrix is embedded in PCM to augment heat transfer. A numerical model is developed to investigate the fluid flow and heat transfer characteristics using the momentum equation and the two-temperature non-equilibrium energy equation coupled with the enthalpy method to account for phase change in PCM. The effects of storage material, porosity and pore-diameter on the net useful energy that can be stored and released during a cycle, are studied. It is found that the first law efficiency of sensible heat storage system is less compared to LHTES. With the decrease in porosity, the first law and second law efficiencies of LHTES increase for both the charging and discharging period. There is no significant variation in energy and exergy efficiencies with the change in pore-diameter of the metal matrix.

  14. Nuclear energy in medium and long term energy generation of Turkey

    International Nuclear Information System (INIS)

    Sarici, L. E.; Yilmaz, S.; Guray, B. S.

    2001-01-01

    In this study; objectives and activities of Nuclear Power Plants Department and Turkish Electricity Generation and Transmission Corporation is briefly mentioned. A brief history of electricity generation, development of Turkish electrical energy sector and development of the installed capacity of country is presented. The history and future perspectives of AKZuyu Nuclear Power Plant Project is sharply outlined. In the light of the current situation in electricity generation and demand projections, importance of nuclear power among the other future electricity generation alternatives of Turkey is underlined

  15. Energy efficiency model for small/medium geothermal heat pump systems

    Directory of Open Access Journals (Sweden)

    Staiger Robert

    2015-06-01

    Full Text Available Heating application efficiency is a crucial point for saving energy and reducing greenhouse gas emissions. Today, EU legal framework conditions clearly define how heating systems should perform, how buildings should be designed in an energy efficient manner and how renewable energy sources should be used. Using heat pumps (HP as an alternative “Renewable Energy System” could be one solution for increasing efficiency, using less energy, reducing the energy dependency and reducing greenhouse gas emissions. This scientific article will take a closer look at the different efficiency dependencies of such geothermal HP (GHP systems for domestic buildings (small/medium HP. Manufacturers of HP appliances must document the efficiency, so called COP (Coefficient of Performance in the EU under certain standards. In technical datasheets of HP appliances, these COP parameters give a clear indication of the performance quality of a HP device. HP efficiency (COP and the efficiency of a working HP system can vary significantly. For this reason, an annual efficiency statistic named “Seasonal Performance Factor” (SPF has been defined to get an overall efficiency for comparing HP Systems. With this indicator, conclusions can be made from an installation, economy, environmental, performance and a risk point of view. A technical and economic HP model shows the dependence of energy efficiency problems in HP systems. To reduce the complexity of the HP model, only the important factors for efficiency dependencies are used. Dynamic and static situations with HP´s and their efficiency are considered. With the latest data from field tests of HP Systems and the practical experience over the last 10 years, this information will be compared with one of the latest simulation programs with the help of two practical geothermal HP system calculations. With the result of the gathered empirical data, it allows for a better estimate of the HP system efficiency, their

  16. Angle and frequency dependence of self-energy from spin fluctuation mediated d-wave pairing for high temperature superconductors.

    Science.gov (United States)

    Hong, Seung Hwan; Choi, Han-Yong

    2013-09-11

    We investigated the characteristics of spin fluctuation mediated superconductivity employing the Eliashberg formalism. The effective interaction between electrons was modeled in terms of the spin susceptibility measured by inelastic neutron scattering experiments on single crystal La(2-x)Sr(x)CuO4 superconductors. The diagonal self-energy and off-diagonal self-energy were calculated by solving the coupled Eliashberg equation self-consistently for the chosen spin susceptibility and tight-binding dispersion of electrons. The full momentum and frequency dependence of the self-energy is presented for optimally doped, overdoped, and underdoped LSCO cuprates in a superconductive state. These results may be compared with the experimentally deduced self-energy from ARPES experiments.

  17. Dose distribution considerations of medium energy electron beams at extended source-to-surface distance

    International Nuclear Information System (INIS)

    Saw, Cheng B.; Ayyangar, Komanduri M.; Pawlicki, Todd; Korb, Leroy J.

    1995-01-01

    Purpose: To determine the effects of extended source-to-surface distance (SSD) on dose distributions for a range of medium energy electron beams and cone sizes. Methods and Materials: The depth-dose curves and isodose distributions of 6 MeV, 10 MeV, and 14 MeV electron beams from a dual photon and multielectron energies linear accelerator were studied. To examine the influence of cone size, the smallest and the largest cone sizes available were used. Measurements were carried out in a water phantom with the water surface set at three different SSDs from 101 to 116 cm. Results: In the region between the phantom surface and the depth of maximum dose, the depth-dose decreases as the SSD increases for all electron beam energies. The effects of extended SSD in the region beyond the depth of maximum dose are unobservable and, hence, considered minimal. Extended SSD effects are apparent for higher electron beam energy with small cone size causing the depth of maximum dose and the rapid dose fall-off region to shift deeper into the phantom. However, the change in the depth-dose curve is small. On the other hand, the rapid dose fall-off region is essentially unaltered when the large cone is used. The penumbra enlarges and electron beam flatness deteriorates with increasing SSD

  18. Progress on the design of the polarized Medium-energy Electron Ion Collider at JLAB

    Energy Technology Data Exchange (ETDEWEB)

    Lin, F.; Bogacz, A.; Brindza, P.; Camsonne, A.; Daly, E.; Derbenev, Ya. S.; Douglas, D.; Ent, R.; Gaskell, D.; Geng, R.; Grames, J.; Guo, J.; Harwood, L.; Hutton, A.; Jordan, K.; Kimber, A.; Krafft, G.; Li, R.; Michalski, T.; Morozov, V. S.; Nadel-Turonski, P.; /Jefferson Lab /Argonne /DESY /Moscow , Inst. Phys. Tech., Dolgoprydny /Dubna, JINR /Northern Illinois U. /Old Doominion U. /Novosibirsk, GOO Zaryad /SLAC /Texas A-M

    2015-07-14

    The Medium-energy Electron Ion Collider (MEIC) at JLab is designed to provide high luminosity and high polarization needed to reach new frontiers in the exploration of nuclear structure. The luminosity, exceeding 1033 cm-2s-1 in a broad range of the center-of-mass (CM) energy and maximum luminosity above 1034 cm-2s-1, is achieved by high-rate collisions of short small-emittance low-charge bunches made possible by high-energy electron cooling of the ion beam and synchrotron radiation damping of the electron beam. The polarization of light ion species (p, d, 3He) can be easily preserved and manipulated due to the unique figure-8 shape of the collider rings. A fully consistent set of parameters have been developed considering the balance of machine performance, required technical development and cost. This paper reports recent progress on the MEIC accelerator design including electron and ion complexes, integrated interaction region design, figure-8-ring-based electron and ion polarization schemes, RF/SRF systems and ERL-based high-energy electron cooling. Luminosity performance is also presented for the MEIC baseline design.

  19. Spin 1990

    International Nuclear Information System (INIS)

    Anton, Gisela

    1990-01-01

    The idea of the intrinsic angular momentum, or 'spin', of a particle has played an essential part in fundamental physics for more than 60 years, and its continuing importance was underlined at the 9th International Symposium on High Energy Spin Physics, held in September in Bonn.

  20. Spin 1990

    Energy Technology Data Exchange (ETDEWEB)

    Anton, Gisela

    1990-12-15

    The idea of the intrinsic angular momentum, or 'spin', of a particle has played an essential part in fundamental physics for more than 60 years, and its continuing importance was underlined at the 9th International Symposium on High Energy Spin Physics, held in September in Bonn.

  1. Low energy collisions of spin-polarized metastable argon atoms with ground state argon atoms

    Science.gov (United States)

    Taillandier-Loize, T.; Perales, F.; Baudon, J.; Hamamda, M.; Bocvarski, V.; Ducloy, M.; Correia, F.; Fabre, N.; Dutier, G.

    2018-04-01

    The collision between a spin-polarized metastable argon atom in Ar* (3p54s, 3P2, M = +2) state slightly decelerated by the Zeeman slower-laser technique and a co-propagating thermal ground state argon atom Ar (3p6, 1S0), both merged from the same supersonic beam, but coming through adjacent slots of a rotating disk, is investigated at the center of mass energies ranging from 1 to 10 meV. The duration of the laser pulse synchronised with the disk allows the tuning of the relative velocity and thus the collision energy. At these sub-thermal energies, the ‘resonant metastability transfer’ signal is too small to be evidenced. The explored energy range requires using indiscernibility amplitudes for identical isotopes to have a correct interpretation of the experimental results. Nevertheless, excitation transfers are expected to increase significantly at much lower energies as suggested by previous theoretical predictions of potentials 2g(3P2) and 2u(3P2). Limits at ultra-low collisional energies of the order of 1 mK (0.086 μeV) or less, where gigantic elastic cross sections are expected, will also be discussed. The experimental method is versatile and could be applied using different isotopes of Argon like 36Ar combined with 40Ar, as well as other rare gases among which Krypton should be of great interest thanks to the available numerous isotopes present in a natural gas mixture.

  2. Technical and economic analysis of integrating low-medium temperature solar energy into power plant

    International Nuclear Information System (INIS)

    Wang, Fu; Li, Hailong; Zhao, Jun; Deng, Shuai; Yan, Jinyue

    2016-01-01

    Highlights: • Seven configurations were studied regarding the integration of solar thermal energy. • Economic analysis was conducted on new built plants and retrofitted power plants. • Using solar thermal energy to preheat high pressure feedwater shows the best performance. - Abstract: In order to mitigate CO_2 emission and improve the efficiency of the utilization of solar thermal energy (STE), solar thermal energy is proposed to be integrated into a power plant. In this paper, seven configurations were studied regarding the integration of STE. A 300 MWe subcritical coal-fired plant was selected as the reference, chemical absorption using monoethanolamine solvent was employed for CO_2 ​capture, and parabolic trough collectors and evacuated tube collectors were used for STE collection. Both technical analysis and economic evaluation were conducted. Results show that integrating solar energy with post-combustion CO_2​ capture can effectively increase power generation and reduce the electrical efficiency penalty caused by CO_2 capture. Among the different configurations, Config-2 and Config-6, which use medium temperature STE to replace high pressure feedwater without and with CO_2 capture, show the highest net incremental solar efficiency. When building new plants, integrating solar energy can effectively reduce the levelized cost of electricity (LCOE). The lowest LCOE, 99.28 USD/MWh, results from Config-6, with a parabolic trough collector price of 185 USD/m"2. When retrofitting existing power plants, Config-6 also shows the highest net present value (NPV), while Config-2 has the shortest payback time at a carbon tax of 50 USD/ton CO_2. In addition, both LCOE and NPV/payback time are clearly affected by the relative solar load fraction, the price of solar thermal collectors and the carbon tax. Comparatively, the carbon tax can affect the configurations with CO_2 capture more clearly than those without CO_2 capture.

  3. The spin correlation parameter and analyzing power in n-p elastic scattering at intermediate energies

    International Nuclear Information System (INIS)

    Abegg, R.; Davis, C.A.; Delheij, P.P.J.; Greeniaus, L.G.; Healey, D.C.; Miller, C.A.; Wait, G.D.; Ahmad, M.; Green, P.W.; Lapointe, C.; McDonald, W.J.; Moss, G.A.; Rodning, N.L.; Roy, G.; Ye, Y.

    1989-06-01

    In order to improve existing I=0 phase shift solutions, the spin correlation parameter, A NN , and the analyzing powers, A 0N and A N0 , have been measured in n-p elastic scattering over an angular range of 50 degrees -150 degrees (c.m.) at three neutron energies, 220, 325 and 425 MeV to an absolute accuracy of ±0.03. The data have a profound effect on various phase parameters, particularly the 1 P 1 , 3 D 2 and ε 1 phase parameters which in some cases change by almost a degree. With exception of the highest energy, the data support the predictions of the latest version of the Bonn potential. Also the analyzing power data (A 0N and A N0 ) measured at 477 MeV in a different experiment over a limited angular range (60 degrees - 80 degrees (c.m.)) are reported here. (Author) 30 refs., 10 figs., 5 tabs

  4. Realization of Rectangular Artificial Spin Ice and Direct Observation of High Energy Topology.

    Science.gov (United States)

    Ribeiro, I R B; Nascimento, F S; Ferreira, S O; Moura-Melo, W A; Costa, C A R; Borme, J; Freitas, P P; Wysin, G M; de Araujo, C I L; Pereira, A R

    2017-10-25

    In this work, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different lattice parameters (rectangular arrays with horizontal and vertical lattice spacings denoted by a and b respectively). Arrays with three different aspect ratios γ = a/b = [Formula: see text], [Formula: see text] and [Formula: see text] are studied. Theoretical calculations of low-energy demagnetized configurations for these same parameters are also presented. Experimental data for demagnetized samples confirm most of the theoretical results. However, the highest energy topology (doubly-charged monopoles) does not emerge in our theoretical model, while they are seen in experiments for large enough γ. Our results also insinuate that the string tension connecting two magnetic monopoles in a pair vanishes in rectangular lattices with a critical ratio γ = γ c  = [Formula: see text], supporting previous theoretical predictions.

  5. Re-energizing energy supply: Electrolytically-produced hydrogen as a flexible energy storage medium and fuel for road transport

    Science.gov (United States)

    Emonts, Bernd; Schiebahn, Sebastian; Görner, Klaus; Lindenberger, Dietmar; Markewitz, Peter; Merten, Frank; Stolten, Detlef

    2017-02-01

    "Energiewende", which roughly translates as the transformation of the German energy sector in accordance with the imperatives of climate change, may soon become a byword for the corresponding processes most other developed countries are at various stages of undergoing. Germany's notable progress in this area offers valuable insights that other states can draw on in implementing their own transitions. The German state of North Rhine-Westphalia (NRW) is making its own contribution to achieving the Energiewende's ambitious objectives: in addition to funding an array of 'clean and green' projects, the Virtual Institute Power to Gas and Heat was established as a consortium of seven scientific and technical organizations whose aim is to inscribe a future, renewable-based German energy system with adequate flexibility. Thus, it is tasked with conceiving of and evaluating suitable energy path options. This paper outlines one of the most promising of these pathways, which is predicated on the use of electrolytically-produced hydrogen as an energy storage medium, as well as the replacement of hydrocarbon-based fuel for most road vehicles. We describe and evaluate this path and place it in a systemic context, outlining a case study from which other countries and federated jurisdictions therein may draw inspiration.

  6. Calculation of the binding energy per nucleon and the quasi-particle interation in nuclear matter under consideration of relativistic medium effects

    International Nuclear Information System (INIS)

    Hippchen, T.

    1985-12-01

    In a first part, nuclear matter calculations have been performed in the Dirac-Brueckner approach using a) a nucleon-nucleon potential of one-boson-exchange (OBE) type and b) a more realistic interaction in which the fictitious σ-exchange of the OBE-model is replaced by explicit 2π- and πρ-exchange diagrams. Both potential models yield the correct empirical binding energy and saturation density. It turns out that the total sum of relativistic effects caused by the emplicit 2 π- and πρ-exchanges is comparable to those due to σ-exchange. In a second part, the nuclear quasiparticle interaction, i.e. the Landau parameters, have been calculated in the central (F), isospin (F'), spin (G) and spin-isospin (G') channel, in an analogous way. Compared to nonrelativistic calculations (including conventional medium corrections like Pauli and dispersion effects), a strong improvement has been found, especially in the F- and G-channel. Finally, the influence of A 1 -exchange is studied, in NN scattering and in nuclear matter. It turns out that, after a suitable and necessary readjustment of some meson parameters, its role is negligibly small. (orig.)

  7. Energetic Communities: Planning support for sustainable energy transition in small- and medium-sized communities

    Directory of Open Access Journals (Sweden)

    Christina Valeska Sager-Klauss

    2016-04-01

    Full Text Available The necessity for transition in the energy sector is beyond dispute and high on the political agendas. Climate change, the depletion of fossil fuels and the vulnerability of economies to resource speculation and unreliable political systems in the producing countries lay path for a broad implementation of smart alternative solutions. This means the integration of more sustainable renewable energy sources in the existing supply structures or the displacement of existing systems by new ones. Cities and communities are central players in the energy transition process. Energy demand is determined by the built environment. Renewable energy production needs space. The conflicts between different interest groups often break out in the context of local implementation measures that affect urban planning and the appearance of landscapes. Small- and medium-sized communities might prove to be game-changers in the overall energy transition because many problems have to be solved within their ambit. Urban planning is dealing with the numerous processes of urban change. Energy is a fairly new task to be addressed and many stakeholders lack experience and criteria for strategic decision making. After a period of fierce determination to turn the wheel against climate change, it seems that there is a growing resignation among politicians, planners and the public because some things have not turned out the way we’d expected and the hope for quick solutions fades. Rebound-effects seem to eat up the savings to a good extent, and alternative ideas of how sustainable energy systems may be put into place have not yet been persuasive in many cases. Energy systems have proved to be complex. They are still perceived to be important but in practice there is a growing uneasiness about the right steps to take. The overarching research question of this thesis is: What do decision makers in smalland medium-sized communities need to become more successful in implementing

  8. A Pair Production Telescope for Medium-Energy Gamma-Ray Polarimetry

    Science.gov (United States)

    Hunter, Stanley D.; Bloser, Peter F.; Depaola, Gerardo; Dion, Michael P.; DeNolfo, Georgia A.; Hanu, Andrei; Iparraguirre, Marcos; Legere, Jason; Longo, Francesco; McConnell, Mark L.; hide

    2014-01-01

    We describe the science motivation and development of a pair production telescope for medium-energy (approximately 5-200 Mega electron Volts) gamma-ray polarimetry. Our instrument concept, the Advanced Energetic Pair Telescope (AdEPT), takes advantage of the Three-Dimensional Track Imager, a low-density gaseous time projection chamber, to achieve angular resolution within a factor of two of the pair production kinematics limit (approximately 0.6 deg at 70 Mega electron Volts), continuum sensitivity comparable with the Fermi-LAT front detector (is less than 3 x 10(exp -6) Mega electron Volts per square centimeter per second at 70 Mega electron Volts), and minimum detectable polarization less than 10% for a 10 milliCrab source in 10(exp 6) s.

  9. Software-Defined Solutions for Managing Energy Use in Small to Medium Sized Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Peffer, Therese [Univ. of California, Berkeley, CA (United States); Council on International Education Exchange (CIEE), Portland, ME (United States); Blumstein, Carl [Council on International Education Exchange (CIEE), Portland, ME (United States); Culler, David [Univ. of California, Berkeley, CA (United States). Electrical Engineering and Computer Sciences (EECS); Modera, Mark [Univ. of California, Davis, CA (United States). Western Cooling Efficiency Center (WCEC); Meier, Alan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-09-10

    The Project uses state-of-the-art computer science to extend the benefits of Building Automation Systems (BAS) typically found in large buildings (>100,000 square foot) to medium-sized commercial buildings (<50,000 sq ft). The BAS developed in this project, termed OpenBAS, uses an open-source and open software architecture platform, user interface, and plug-and-play control devices to facilitate adoption of energy efficiency strategies in the commercial building sector throughout the United States. At the heart of this “turn key” BAS is the platform with three types of controllers—thermostat, lighting controller, and general controller—that are easily “discovered” by the platform in a plug-and-play fashion. The user interface showcases the platform and provides the control system set-up, system status display and means of automatically mapping the control points in the system.

  10. Beam dynamics and commissioning of low and medium energy H- beam at Linac4

    CERN Document Server

    Satri, Masoomeh Yarmohammadi; Lombardi, Alessandra; Lamehi-Rachti , Mohammad

    The First step of the CERN Large Hadron Collider injectors upgrade (LIU) project is Linac4. It accelerates H- ions to 160 MeV in an 80 m long accelerator housed in a tunnel 12 m underground, presently under construction. It will replace the present 50 MeV proton Linac2 as injector of the proton accelerator complex to increase the LHC luminosity. It consists of a 45 keV RF volume source, a twosolenoid Low Energy Beam Transport (LEBT), a 352.2 MHz Radio Frequency Quadrupole (RFQ) accelerating the beam to 3 MeV, a Medium Energy Beam Transport (MEBT) line. The MEBT houses a fast chopper to selectively remove unwanted micro-bunches in the 352 MHz sequence and avoid losses at capture in the CERN PSB (1 MHz). After chopping, the beam acceleration continues by a 50 MeV Drift Tube Linac (DTL), a 100 MeV Cell-Coupled Drift Tube Linac and a Pi-Mode Structure bringing the beam to the final energy of 160 MeV. Linac4 has been commissioned with a temporary source up to 12 MeV. The beam commissioning stages of Linac4 in LEBT...

  11. Towards smart energy systems: application of kernel machine regression for medium term electricity load forecasting.

    Science.gov (United States)

    Alamaniotis, Miltiadis; Bargiotas, Dimitrios; Tsoukalas, Lefteri H

    2016-01-01

    Integration of energy systems with information technologies has facilitated the realization of smart energy systems that utilize information to optimize system operation. To that end, crucial in optimizing energy system operation is the accurate, ahead-of-time forecasting of load demand. In particular, load forecasting allows planning of system expansion, and decision making for enhancing system safety and reliability. In this paper, the application of two types of kernel machines for medium term load forecasting (MTLF) is presented and their performance is recorded based on a set of historical electricity load demand data. The two kernel machine models and more specifically Gaussian process regression (GPR) and relevance vector regression (RVR) are utilized for making predictions over future load demand. Both models, i.e., GPR and RVR, are equipped with a Gaussian kernel and are tested on daily predictions for a 30-day-ahead horizon taken from the New England Area. Furthermore, their performance is compared to the ARMA(2,2) model with respect to mean average percentage error and squared correlation coefficient. Results demonstrate the superiority of RVR over the other forecasting models in performing MTLF.

  12. Medium energy nucleon-nucleus scattering theory by semi-classical distorted wave approximation

    Energy Technology Data Exchange (ETDEWEB)

    Ogata, Kazuyuki [Kyushu Univ., Fukuoka (Japan)

    1998-07-01

    The semiclassical distorted wave model (SCDW) is one of the quantum mechanical models for nucleon inelastic and charge exchange scattering at intermediate energies. SCDW can reproduce the double differential inclusive cross sections for multi-step direct processes quite well in the angular and outgoing energy regions where the model is expected to work. But the model hitherto assumed on-the-energy-shell (on-shell) nucleon-nucleon scattering in the nucleus, neglecting the difference in the distorting potentials for the incoming and the outgoing particles and also the Q-value in the case of (p,n) reactions. There had also been a problem in the treatment of the exchange of colliding nucleons. Now we modify the model to overcome those problems and put SCDW on sounder theoretical foundations. The modification results in slight reduction (increase) of double differential cross sections at forward (backward) angles. We also examine the effect of the in-medium modification of N-N cross sections in SCDW and find it small. A remedy of the disagreement at very small and large angles in terms of the Wigner transform of the single particle density matrix is also discussed. This improvement gives very promising results. (author)

  13. Single reference Coupled Cluster treatment of nearly degenerate problems: Cohesive energy of antiferromagnetic lattices of spin 1 centers

    International Nuclear Information System (INIS)

    Malrieu, Jean-Paul

    2012-01-01

    Lattices of antiferromagnetically coupled spins, ruled by Heisenberg Hamiltonians, are intrinsically highly degenerate systems. The present work tries to estimate the ground state energy of regular bipartite spin lattices of S = 1 sites from a single reference Coupled Cluster expansion starting from a Néel function, taken as reference. The simultaneous changes of spin momentum on adjacent sites play the role of the double excitations in molecular electronic problems. Propagation of the spin changes plays the same role as the triple excitations. The treatment takes care of the deviation of multiple excitation energies from additivity. Specific difficulties appear for 1D chains, which are not due to a near degeneracy between the reference and the vectors which directly interact with it but to the complexity of the processes which lead to the low energy configurations where a consistent reversed-Néel domain is created inside the Néel starting spin wave. Despite these difficulties a reasonable value of the cohesive energy is obtained.

  14. Single reference Coupled Cluster treatment of nearly degenerate problems: Cohesive energy of antiferromagnetic lattices of spin 1 centers

    Science.gov (United States)

    Malrieu, Jean-Paul

    2012-06-01

    Lattices of antiferromagnetically coupled spins, ruled by Heisenberg Hamiltonians, are intrinsically highly degenerate systems. The present work tries to estimate the ground state energy of regular bipartite spin lattices of S = 1 sites from a single reference Coupled Cluster expansion starting from a Néel function, taken as reference. The simultaneous changes of spin momentum on adjacent sites play the role of the double excitations in molecular electronic problems. Propagation of the spin changes plays the same role as the triple excitations. The treatment takes care of the deviation of multiple excitation energies from additivity. Specific difficulties appear for 1D chains, which are not due to a near degeneracy between the reference and the vectors which directly interact with it but to the complexity of the processes which lead to the low energy configurations where a consistent reversed-Néel domain is created inside the Néel starting spin wave. Despite these difficulties a reasonable value of the cohesive energy is obtained.

  15. Subthreshold pion production study with heavy ions at low and medium energy

    International Nuclear Information System (INIS)

    Rebreyend, D.

    1988-02-01

    In the domain of subthreshold pion production with heavy ions at low and medium energy (40-100 MeV/u), only Π 0 have been up to now, extensively studied. The incompleteness of the charged pion data and especially the lack of results for pions of energy less than 30 MeV have led to conceive the magnetic spectrometer SPIC. In the present work, we demonstrate that this spectrometer is particularly well suited for the detection of low energy charged pions (Inferior threshold of detection: T Π = 7 MeV), emitted around 0 0 in heavy ion collisions. Principle and performances, successfully tested at 38 and 93 MeV/u, are described in detail. The main characteristics of a Π 0 spectrometer, that was used to realize a comparative experiment of Π 0 production, are then given. The last chapter is devoted to experimental results. First, we present the results obtained with the 16 0 beam of 38 MeV/u of the SARA accelerator, in charged pions (Al and Ni targets) and in Π 0 (Al and Au targets). A comparison of the data Π - /Π 0 seems to indicate that coulomb effects are surprisingly small. Finally, we report the data obtained with the 16 0 beam of 93 MeV/u of GANIL. In contrast with low energy data, coulomb effects are very strong (ratio Π - /Π + = 100 for pions of low energy with heavy targets) and allowed us to extract informations on the geometry of the collision [fr

  16. Medium-Term Renewable Energy Market Report 2013: Market trends and projections to 2018

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    Renewable electricity generation increased strongly worldwide in 2012, and deployment is occurring in a greater number of markets. However, the story of renewable energy development is becoming more complex. Short-term indicators in some regions of the globe have pointed to increased challenges. Despite remaining high, global new investment in renewable energy fell in 2012. Policy uncertainties, economic challenges, incentive reductions and competition from other energy sources clouded the investment outlook for some markets. Some countries and regions have faced difficulties in integrating variable renewables in their power grids. The renewable manufacturing industry, particularly solar and wind, entered a deeper period of restructuring and consolidation. Nevertheless, despite economic, policy and industry turbulence, the underlying fundamentals for renewable deployment remain robust. Even with challenges in some countries, more positive developments elsewhere continue to drive global growth. Competitive opportunities for renewables are emerging across traditional and new markets. While OECD countries remain a driver of renewable power development, non-OECD countries are increasingly accounting for overall growth. The roles of biofuels for transport and renewable heat are also increasing, though at somewhat slower rates than renewable electricity. The Medium-Term Renewable Energy Market Report 2013 assesses market trends for the renewable electricity, biofuels for transport and renewable heat sectors, identifying drivers and challenges to deployment, and making projections through 2018. The analysis features in-depth renewable electricity market analysis and forecasts for a slate of countries in the OECD and non-OECD. The report also presents an outlook for renewable electricity technologies, global biofuels supply, final energy use of renewables for heat and prospects for renewable investment.

  17. Technical Support Document: Development of the Advanced Energy Design Guide for Medium Box Retail -- 50% Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Hale, E. T.; Macumber, D. L.; Long, N. L.; Griffith, B. T.; Benne, K. S.; Pless, S. D.; Torcellini, P. A.

    2008-09-01

    This report provides recommendations that architects, designers, contractors, developers, owners, and lessees of medium box retail buildings can use to achieve whole-building energy savings of at least 50% over ASHRAE Standard 90.1-2004. The recommendations are given by climate zone and address building envelope, fenestration, lighting systems, HVAC systems, building automation and controls, outside air treatment, service water heating, plug loads, and photovoltaic systems. The report presents several paths to 50% savings, which correspond to different levels of integrated design. These are recommendations only, and are not part of a code or standard. The recommendations are not exhaustive, but we do try to emphasize the benefits of integrated building design, that is, a design approach that analyzes a building as a whole system, rather than as a disconnected collection of individually engineered subsystems.

  18. Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

    Science.gov (United States)

    Razaque, Abdul; Elleithy, Khaled M.

    2014-01-01

    This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN), which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS), which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM) model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS), which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

  19. Energy-efficient boarder node medium access control protocol for wireless sensor networks.

    Science.gov (United States)

    Razaque, Abdul; Elleithy, Khaled M

    2014-03-12

    This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN), which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS), which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM) model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS), which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

  20. Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Abdul Razaque

    2014-03-01

    Full Text Available This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC for wireless sensor networks (WSNs, which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN, which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS, which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS, which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

  1. Inelastic neutron scattering in the spin wave energy gap of the polydomain γ-Mn(12%Ge) alloy

    International Nuclear Information System (INIS)

    Jankowska-Kisielinska, J.; Mikke, K.

    1999-01-01

    The subject of the present experiment was the investigation of the inelastic neutron scattering (INS) for energy transfers lower than and close to the energy gap of the spin wave spectrum for long wavelengths. The aim was a search for the excitations at the magnetic Brillouin zone (MBZ) boundary in polydomain Mn(12%Ge) alloy. The present measurements were performed by a 3-axis spectrometer at Maria Reactor at IEA in Swierk. We observed the INS in the polydomain Mn(12%Ge) alloy for energies smaller than and close to the energy gap value of the spin wave spectrum at room temperature. The observed intensity can be treated as a sum of intensity of neutrons scattered on spin waves around magnetic Brillouin zone centre and that of neutrons scattered on fluctuations at the zone boundary. The intensity of both components for energies 2-6 MeV was found to be of the same order. For higher energies spin waves around magnetic zone centre dominate. (author)

  2. Medium energy high intensity proton accelerator (MEHIPA): Reference Design Report (RDR) Ver. 1.0

    International Nuclear Information System (INIS)

    2016-11-01

    Recent progress in accelerator technology has made it possible to use a proton accelerator to produce nuclear energy. In an accelerator-driven system (ADS), a high-intensity proton accelerator is used to produce protons of around 1 GeV energy, which strike a target such as lead or tungsten to produce spallation neutrons. ADS can be used to produce power, incinerate minor actinides and long-lived fission products, and for the utilization of thorium as an alternative nuclear fuel. The accelerator for ADS has to produce high energy (1 GeV) protons, and deliver tens of milli amperes of beam current with minimum (< 1 nA/m) beam loss for hands-on maintenance of the accelerator. This makes the development of accelerators for ADS very challenging. In India, it is planned to take a staged approach towards development of the requisite accelerator technology, and it is planned to develop the accelerator in three phases: 20 MeV, 200 MeV and 1 GeV. This report presents a reference design report for the Medium Energy High Intensity Proton Accelerator (MEHIPA) which will accelerate the beam to 200 MeV. The linac consists of a 3 MeV normal conducting RFQ followed by three families of superconducting Single Spoke Resonators (SSR) to accelerate the beam to 200 MeV. The major elements of the physics design of MEHIPA, as well as layouts and specifications of the major accelerator sub-systems are presented in this report. (author)

  3. EFFECT OF LOW ENERGY VERSUS MEDIUM ENERGY RADIAL SHOCK WAVE THERAPY IN THE TREATMENT OF CHRONIC PLANTER FASCIITIS

    Directory of Open Access Journals (Sweden)

    Khaled Z. Fouda

    2016-02-01

    Full Text Available Background: Plantar fasciitis (PF is the most common cause of heel pain and it can often be a challenge for clinicians to treat successfully. Radial shock wave therapy (RSWT has been introduced recently for treatment of musculoskeletal disorders. Different energy levels of shock wave therapy have been used in the literatures for treatment of PF with no clear settled parameters. Therefore, the purpose of this study was intended to investigate and compare the efficacy of two different energy levels of RSWT on PF patients. Methods: Forty patients having unilateral chronic PF were recruited for the study from orthopedic outpatient clinics of Cairo University hospitals and National Institute of Neuromotor System Cairo Egypt, with a mean age of (47.15±4.57 years. Patients were randomly assigned into two equal groups. Group (A treated with low intensity level of 1.6 bars (0.16 mJ/mm2 RSWT and group (B treated with medium intensity level of 4 bars (0.38 mJ/mm2 RSWT. Functional assessment of the foot based on Foot Function Index (FFI and Present pain intensity was measured during rest by Visual Analogue Scale (VAS. Results: There was as significant decreased in the total FFI scores from (118.42 ±6.51 to (81.37 ±3.46 for group (A and from (118.93 ±6.85 to (58.50 ±3.22 for group (B. Also regarding VAS Scores there was as significant decreased in the pain intensity from (5.11 ±0.41 to (2.85 ±0.31 for group (A and from (4.95 ±0.39 to (2.05 ±0.22 for group (B. Conclusion: Radial shock wave therapy is an effective modality that should be considered in the treatment of chronic PF, while the medium energy level RSWT is better than the low energy level RSWT in regarding to the measured treatment outcomes.

  4. High-spin states in 66Zn

    International Nuclear Information System (INIS)

    Bruandet, J.F.; Agard, M.; Giorni, A.; Longequeue, J.P.; Morand, C.; Tsan Ung Chan.

    1975-01-01

    The structure of 66 Zn has been investigated by studying the yield functions, angular distributions and coincidence relationships of the γ-rays emitted during bombardment of an enriched 64 Ni foil by α particles of medium energy 27MeV. Spins up to 10 h were assigned to observed states [fr

  5. IceCube constraints on fast-spinning pulsars as high-energy neutrino sources

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Ke [Department of Astronomy, University of Maryland, College Park, MD, 20742 (United States); Kotera, Kumiko [Institut d' Astrophysique de Paris, UMR 7095 – CNRS, Université Pierre $ and $ Marie Curie, 98 bis boulevard Arago, 75014, Paris (France); Murase, Kohta [Department of Physics, Department of Astronomy and Astrophysics, Center for Particle and Gravitational Astrophysics, The Pennsylvania State University, PA 16802 (United States); Olinto, Angela V., E-mail: kefang@umd.edu, E-mail: kotera@iap.fr, E-mail: murase@psu.edu, E-mail: olinto@kicp.uchicago.edu [Department of Astronomy and Astrophysics, Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States)

    2016-04-01

    Relativistic winds of fast-spinning pulsars have been proposed as a potential site for cosmic-ray acceleration from very high energies (VHE) to ultrahigh energies (UHE). We re-examine conditions for high-energy neutrino production, considering the interaction of accelerated particles with baryons of the expanding supernova ejecta and the radiation fields in the wind nebula. We make use of the current IceCube sensitivity in diffusive high-energy neutrino background, in order to constrain the parameter space of the most extreme neutron stars as sources of VHE and UHE cosmic rays. We demonstrate that the current non-observation of 10{sup 18} eV neutrinos put stringent constraints on the pulsar scenario. For a given model, birthrates, ejecta mass and acceleration efficiency of the magnetar sources can be constrained. When we assume a proton cosmic ray composition and spherical supernovae ejecta, we find that the IceCube limits almost exclude their significant contribution to the observed UHE cosmic-ray flux. Furthermore, we consider scenarios where a fraction of cosmic rays can escape from jet-like structures piercing the ejecta, without significant interactions. Such scenarios would enable the production of UHE cosmic rays and help remove the tension between their EeV neutrino production and the observational data.

  6. A medium-chain fatty acid as an alternative energy source in mouse preimplantation development.

    Science.gov (United States)

    Yamada, Mitsutoshi; Takanashi, Kazumi; Hamatani, Toshio; Hirayama, Akiyoshi; Akutsu, Hidenori; Fukunaga, Tomoko; Ogawa, Seiji; Sugawara, Kana; Shinoda, Kosaku; Soga, Tomoyoshi; Umezawa, Akihiro; Kuji, Naoaki; Yoshimura, Yasunori; Tomita, Masaru

    2012-01-01

    To further optimize the culturing of preimplantation embryos, we undertook metabolomic analysis of relevant culture media using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). We detected 28 metabolites: 23 embryo-excreted metabolites including 16 amino acids and 5 media-derived metabolites (e.g., octanoate, a medium-chain fatty acid (MCFA)). Due to the lack of information on MCFAs in mammalian preimplantation development, this study examined octanoate as a potential alternative energy source for preimplantation embryo cultures. No embryos survived in culture media lacking FAs, pyruvate, and glucose, but supplementation of octanoate rescued the embryonic development. Immunoblotting showed significant expression of acyl-CoA dehydrogenase and hydroxyacyl-CoA dehydrogenase, important enzymes for ß-oxidation of MCFAs, in preimplantation embryo. Furthermore, CE-TOFMS traced [1-(13)C(8)] octanoate added to the culture media into intermediate metabolites of the TCA cycle via ß-oxidation in mitochondria. These results are the first demonstration that octanoate could provide an efficient alternative energy source throughout preimplantation development.

  7. Microscopic study of elastic and inelastic ALPHA-nucleus scattering at medium energies

    International Nuclear Information System (INIS)

    Dao Tien Khoa; Hoang Si Than; Do Cong Cuong; Ngo Van Luyen; Nguyen Ngoc Quynh; Nguyen Tuan Anh

    2007-01-01

    Analyses of the inelastic α + 12 C scattering at medium energies have indicated that the strength of the Hoyle state (the isoscalar O 2 + excitation at 7.65 MeV in 12 C) seems to exhaust only 7 to 9% of the monopole energy weighted sum rule (EWSR), compared to about 15% of the EWSR extracted from inelastic electron scattering data. The full monopole transition strength predicted by realistic microscopic α-cluster models of the Hoyle state can be shown to exhaust up to 22% of the EWSR. To explore the missing monopole strength in the inelastic α + 12 C scattering, we have performed a fully microscopic folding model analysis of the inelastic α + 12 C scattering at E lab =104 to 240 MeV using the 3-α resonating group wave function of the Hoyle state obtained by Kamimura, and a complex density-dependent M3Y interaction newly parametrized based on the Brueckner Hartree Fock results for nuclear matter. Our folding model analysis has shown consistently that the missing monopole strength of the Hoyle state is not associated with the uncertainties in the analysis of the α + 12 C scattering, but is most likely due to the short lifetime and weakly bound structure of this state which significantly enhances absorption in the exit α + 12 C * (O 2 + ) channel. (author)

  8. Charge equilibrium and radiation of low-energy cosmic rays passing through interstellar medium

    International Nuclear Information System (INIS)

    Rule, D.W.; Omidvar, K.

    1979-01-01

    The charge equilibrium and radiation an oxygen and an iron beam in the MeV per nucleon energy range, representing a typical beam of low-energy cosmic rays passing through the interstellar medium, are considered. Electron loss of the beam has been taken into account by means of the first Born approximation allowing for the target atom to remain unexcited, or to be excited to all possible states. Electron-capture cross sections have been calculated by means of the scaled Oppenheimer-Brinkman-Kramers approximation, taking into account of atomic shells of the target atoms and capture into all excited states of the projectile. The capture and loss cross sections are found to be within 20%--30% of the existing experimental values for most of the cases considered. Radiation of the beam due to electron capture into the excited states of the ion, collisional excitation, and collisional inner-shell ionization, taking into account the fluorescence yield of the ions has been considered. Effective X-ray production cross sections and mutliplicities for the most energetic X-ray lines emitted by the Fe and O beams have been calculated, and error estimates made for the results

  9. Charge equilibrium and radiation of low-energy cosmic rays passing through interstellar medium

    Science.gov (United States)

    Rule, D. W.; Omidvar, K.

    1979-01-01

    The charge equilibrium and radiation of an oxygen and an iron beam in the MeV per nucleon energy range, representing a typical beam of low-energy cosmic rays passing through the interstellar medium, are considered. Electron loss of the beam has been taken into account by means of the first Born approximation, allowing for the target atom to remain unexcited or to be excited to all possible states. Electron-capture cross sections have been calculated by means of the scaled Oppenheimer-Brinkman-Kramers approximation, taking into account all atomic shells of the target atoms and capture into all excited states of the projectile. The capture and loss cross sections are found to be within 20%-30% of the existing experimental values for most of the cases considered. Radiation of the beam due to electron capture into the excited states of the ion, collisional excitation, and collisional inner-shell ionization, taking into account the fluorescence yield of the ions, has been considered. Effective X-ray production cross sections and multiplicities for the most energetic X-ray lines emitted by the Fe and O beams have been calculated, and error estimates made for the results.

  10. MCNP6 Simulation of Light and Medium Nuclei Fragmentation at Intermediate Energies

    Energy Technology Data Exchange (ETDEWEB)

    Mashnik, Stepan Georgievich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kerby, Leslie Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-22

    MCNP6, the latest and most advanced LANL Monte Carlo transport code, representing a merger of MCNP5 and MCNPX, is actually much more than the sum of those two computer codes; MCNP6 is available to the public via RSICC at Oak Ridge, TN, USA. In the present work, MCNP6 was validated and verified (V&V) against different experimental data on intermediate-energy fragmentation reactions, and results by several other codes, using mainly the latest modifications of the Cascade-Exciton Model (CEM) and of the Los Alamos version of the Quark-Gluon String Model (LAQGSM) event generators CEM03.03 and LAQGSM03.03. It was found that MCNP6 using CEM03.03 and LAQGSM03.03 describes well fragmentation reactions induced on light and medium target nuclei by protons and light nuclei of energies around 1 GeV/nucleon and below, and can serve as a reliable simulation tool for different applications, like cosmic-ray-induced single event upsets (SEU’s), radiation protection, and cancer therapy with proton and ion beams, to name just a few. Future improvements of the predicting capabilities of MCNP6 for such reactions are possible, and are discussed in this work.

  11. Cross correlation analysis of medium energy gamma rays for the northern hemisphere

    International Nuclear Information System (INIS)

    Long, J.; Zanrosso, E.; Zych, A.D.; White, R.S.

    1982-01-01

    Data obtained with the UCR gamma telescope have been analyzed using the cross-correlation method. The observations extended over 37.5 hr from 0930 UT, 30 Sept. to 2300 UT, 1 oct. 1978 at 32deg N. Lat. (Palestine, Texas). The Crab Nebula- Anticenter region was observed on consecutive days. The telescope's wide field-of-view permitted the search for a number of other medium energy (1-30 MeV) source candidates. As the telescope swept the sky, the count rates for fixed celestial directions were correlated with the expected response as a function of time and telescope geometry. Similar correlations were carried out for sources measured in the laboratory and computer-simulated sources. In the correlation method the time independence and azimuthal symmetry of the atmospheric and cosmic diffuse backgrounds provide zero correlation. In contrast, a celestial source produces an asymmetric response with respect to the azimuthal direction which varies predictably in time to give a positive correlation. Preliminary correlation skymaps of the Anticenter region are presented and their statistical significance discussed. An energy spectrum obtained from the ''correlated counts'' is compared with measurements by other methods

  12. Medium access control and hardware prototype designs for low-energy wireless sensor networks

    Energy Technology Data Exchange (ETDEWEB)

    Kohvakka, M.

    2009-07-01

    A Wireless Sensor Network (WSN) is an emerging technology consisting of small, cheap, and ultra-low energy sensor nodes, which cooperatively monitor physical quantities, actuate, and perform data processing tasks. A deployment may comprise thousands of randomly distributed autonomous nodes, which must self-configure and create a multi-hop network topology.This thesis focuses on low-energy WSNs targeting to long network lifetime. The main research problem is the combination of adaptive and scalable multi-hop networking with constrained energy budget, processing power, and communication bandwidth. The research problem is approached by energy-efficient protocols and low-power sensor node platforms. The main contribution of this thesis is an energy-efficient Medium Access Control (MAC) design for TUTWSN (Tampere University of Technology Wireless Sensor Network). The design comprises channel access and networking mechanisms, which specify data exchange, link synchronization, network self-configuration, and neighbor discovery operations. The second outcome are several low-power sensor node platforms, which have been designed and implemented to evaluate the performance of the MAC design and hardware components in real deployments. The third outcome are the performance models and analysis of several MAC designs including TUTWSN, IEEE 802.15.4, and the most essential research proposals.The results and conclusion of this Thesis indicate that it is possible to implement multi-hop WSNs in harsh and dynamic operation conditions with years of lifetime using current low-cost components and batteries. Energy analysis results indicate that the lowest energy consumption is achieved by using simple and high data-rate transceivers. It is also critical to minimize sleep mode power consumption of all components and to use accurate wake-up timers. However, the selection of components constitutes only a minor part of the solution, and an energy-efficient MAC layer design being able to

  13. A program in medium energy nuclear physics. Progress report and continuation proposal October 1, 1995

    International Nuclear Information System (INIS)

    Berman, B.L.; Dhuga, K.S.

    1995-01-01

    This progress report and continuation proposal summarizes our achievements for the period from July 1, 1994 to September 30, 1995 and requests continued funding for our program in experimental medium-energy nuclear physics. The focus of our program remains the understanding of the short-range part of the strong interaction in the nuclear medium. In the past year we have focused our attention ever more sharply on experiments with real tagged photons, and we have successfully defended two new experimental proposals: Photofission of Actinide and Preactinide Nuclei at SAL and Photoproduction of the ρ Meson from the Proton with Linearly Polarized Photons at CEBAF. (We are co-spokespersons on two previously approved Hall-B experiments at CEBAF, Photoreactions on 3 He and Photoabsorption and Photofission of Nuclei.) As part of the team that is instrumenting the Photon Tagger for Hall B; we report excellent progress on the focal-plane detector array that is being built at our Nuclear Detector Laboratory, as well as progress on our plans for instrumentation of a tagged polarized-photon beam using coherent bremsstrahlung. Also, we shall soon receive a large computer system (from the SSC) which will form the basis for our new Data Analysis Center, which, like the Nuclear Detector Laboratory, will be operated under the auspices of The George Washington University Center for Nuclear Studies. Finally, during the past year we have published six more papers on the results of our measurements of pion scattering at LAMPF and of electron scattering at NIKHEF and Bates, and we can report that nearly all of the remaining papers documenting this long series of measurements are in the pipeline

  14. Medium energy measurements of n-n parameters: Progress in research, January 1, 1986-December 31, 1986

    International Nuclear Information System (INIS)

    Riley, P.J.

    1987-01-01

    A major part of the work has been and will continue to be associated with research done at the Nucleon Physics Laboratory (NPL) at the Los Alamos Meson Physics Facility (LAMPF). The aim of the experimental program is the determination of the nucleon-nucleon amplitudes at medium energy. The required data include both elastic and inelastic experiments, and in addition the measurement of polarization and polarization transfer parameters. We have been emphasizing single pion production measurements using polarized proton beams, and expect that our present data base will provide stringent tests of theoretical models. With the development of the LAMPF high intensity polarized proton source, we expect that a reasonably intense beam of medium energy polarized neutrons will become available, and are planning a series of experiments utilizing polarized neutrons to determine the importance of the I = 0 reaction amplitudes at medium energies

  15. Bridging the energy gap through small and medium sized nuclear reactors in India

    International Nuclear Information System (INIS)

    Srivastava, R.

    1987-01-01

    India is the only country in the world which is employing small sized nuclear reactors for its nuclear power programme. It has now embarked on a programme of augmenting the contribution of the nuclear power by way of employing both medium and small sized nuclear reactors in the next 15 years. This paper discusses the Indian experience and its efforts for industrial mobilisation for rapidly constructing 235/500 MWe nuclear reactor units in a period of about 8 to 9 years. The current energy situation in India and this context the near term role of nuclear power for supplementing the existing sources of commercial energy have been evaluated. Nuclear power has reached such a stage of maturity whereby it has now become a commercially viable source of electricity and it could be utilised on large scale to bridge the energy gap. At present six reactor units of 210/235 MWe capacity are in operation and eight more are in different stages of construction. While we are continuing with the construction of 235 MWe units, a programme of being pursued to construct 550 MWe capacity reactor units from midnineties onwards. This has become possible with the strengthening of regional electricity grids and simultaneous efforts undertaken for augmentation of fuel supply, heavy water production and industrial infrastructure. For a developing country like India, implementation of a sizable nuclear power programme has posed certain special challenges as major inputs are required to be made available with indigeneous efforts. This paper discusses such challenges and presents the ways and means adopted to surmount them. Other developing countries with conditions comparable to those in India could benefit from Indian experience in this regard. This paper also proposes India's willingness to cooperate with other countries for exchange of information and assistance in terms of technical knowhow. (author)

  16. Medium energy measurements of N-N parameters: Progress report, January 1, 1988--December 31, 1988

    International Nuclear Information System (INIS)

    Riley, P.J.

    1988-01-01

    We report here progress made for the period January 1, 1988, to December 31, 1988, for the Department of Energy Three-year Grant No. DE-FG05-88ER40446, first year. A major part of the work has been and will continue to be associated with research done at the Nucleon Physics Laboratory (NPL) at the Los Alamos Meson Physics Facility (LAMPF). The aim of the experimental program is the determination of the nucleon-nucleon amplitudes at medium energies. The required data include both elastic and inelastic experiments, and in addition the measurement of polarization and polarization transfer parameters. The measurements can be broadly categorized into those of proton-proton elastic scattering, which probe the isospin-1 elastic channel, neutron-proton elastic scattering, which allow measurements of isospin-0 amplitudes, proton-proton inelastic scattering, and neutron-proton inelastic scattering. We are nearing completion of a long-range series of p-p elastic scattering measurements, and believe that the required goals have been achieved. During the past few years we have emphasized proton-proton inelastic scattering measurements, and believe that the determination of the I = 1 inelastic phase shifts is progressing well. The I = 0 amplitudes, both elastic, and inelastic, are still poorly determined, at best. These measurements require a much more intense polarized neutron beam than is yet available, and therefore have needed the high-intensity optically pumped polarized ion source, due to come on-line during late 1989. During the past year our work emphasized p-p elastic differential scattering cross-section measurements in the energy range 500--800 MeV at LAMPF. The measurements aimed for an absolute accuracy of 1%, and we believe that this was achieved. We also have been involved in what we believe is the first partial wave analysis of pp → npπ + data

  17. Co-generation and innovative heat storage systems in small-medium CSP plants for distributed energy production

    Science.gov (United States)

    Giaconia, Alberto; Montagnino, Fabio; Paredes, Filippo; Donato, Filippo; Caputo, Giampaolo; Mazzei, Domenico

    2017-06-01

    CSP technologies can be applied for distributed energy production, on small-medium plants (on the 1 MW scale), to satisfy the needs of local communities, buildings and districts. In this perspective, reliable, low-cost, and flexible small/medium multi-generative CSP plants should be developed. Four pilot plants have been built in four Mediterranean countries (Cyprus, Egypt, Jordan, and Italy) to demonstrate the approach. In this paper, the plant built in Italy is presented, with specific innovations applied in the linear Fresnel collector design and the Thermal Energy Storage (TES) system, based on a single the use of molten salts but specifically tailored for small scale plants.

  18. Chiral magnetic currents with QGP medium response in heavy-ion collisions at RHIC and LHC energies

    Science.gov (United States)

    She, Duan; Feng, Sheng-Qin; Zhong, Yang; Yin, Zhong-Bao

    2018-03-01

    We calculate the electromagnetic current with a more realistic approach in the RHIC and LHC energy regions in the article. We take the partons formation time as the initial time of the magnetic field response of QGP medium. The maximum electromagnetic current and the time-integrated current are two important characteristics of the chiral magnetic effect (CME), which can characterize the intensity and duration of fluctuations of CME. We consider the finite frequency response of CME to a time-varying magnetic field, find a significant impact from QGP medium feedback, and estimate the generated electromagnetic current as a function of time, beam energy and impact parameter.

  19. Alternating magnetic field energy absorption in the dispersion of iron oxide nanoparticles in a viscous medium

    Energy Technology Data Exchange (ETDEWEB)

    Smolkova, Ilona S. [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, T.G. Masaryk Sq. 275, 762 72 Zlin (Czech Republic); Kazantseva, Natalia E., E-mail: nekazan@yahoo.com [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Babayan, Vladimir; Smolka, Petr; Parmar, Harshida; Vilcakova, Jarmila [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Schneeweiss, Oldrich; Pizurova, Nadezda [Institute of Physics of Materials, Academy of Sciences of the Czech Republic, Zizkova 22, 616 62 Brno (Czech Republic)

    2015-01-15

    Magnetic iron oxide nanoparticles were obtained by a coprecipitation method in a controlled growth process leading to the formation of uniform highly crystalline nanoparticles with average size of 13 nm, which corresponds to the superparamagnetic state. Nanoparticles obtained are a mixture of single-phase nanoparticles of magnetite and maghemite as well as nanoparticles of non-stoichiometric magnetite. The subsequent annealing of nanoparticles at 300 °C in air during 6 h leads to the full transformation to maghemite. It results in reduced value of the saturation magnetization (from 56 emu g{sup −1} to 48 emu g{sup −1}) but does not affect the heating ability of nanoparticles. A 2–7 wt% dispersion of as-prepared and annealed nanoparticles in glycerol provides high heating rate in alternating magnetic fields allowed for application in magnetic hyperthermia; however the value of specific loss power does not exceed 30 W g{sup −1}. This feature of heat output is explained by the combined effect of magnetic interparticle interactions and the properties of the carrier medium. Nanoparticles coalesce during the synthesis and form aggregates showing ferromagnetic-like behavior with magnetization hysteresis, distinct sextets on Mössbauer spectrum, blocking temperature well about room temperature, which accounts for the higher energy barrier for magnetization reversal. At the same time, low specific heat capacity of glycerol intensifies heat transfer in the magnetic dispersion. However, high viscosity of glycerol limits the specific loss power value, since predominantly the Neel relaxation accounts for the absorption of AC magnetic field energy. - Highlights: • Mixed phase iron oxide magnetic nanoparticles were obtained by coprecipitation. • A part of nanoparticles was annealed at 300 °C to achieve the single-phase γ-Fe{sub 2}O{sub 3}. • Nanoparticles revealed ferromagnetic-like behavior due to interparticle interactions. • Nanoparticles glycerol

  20. Global potential energy surface of ground state singlet spin O4

    Science.gov (United States)

    Mankodi, Tapan K.; Bhandarkar, Upendra V.; Puranik, Bhalchandra P.

    2018-02-01

    A new global potential energy for the singlet spin state O4 system is reported using CASPT2/aug-cc-pVTZ ab initio calculations. The geometries for the six-dimensional surface are constructed using a novel point generation scheme that employs randomly generated configurations based on the beta distribution. The advantage of this scheme is apparent in the reduction of the number of required geometries for a reasonably accurate potential energy surface (PES) and the consequent decrease in the overall computational effort. The reported surface matches well with the recently published singlet surface by Paukku et al. [J. Chem. Phys. 147, 034301 (2017)]. In addition to the O4 PES, the ground state N4 PES is also constructed using the point generation scheme and compared with the existing PES [Y. Paukku et al., J. Chem. Phys. 139, 044309 (2013)]. The singlet surface is constructed with the aim of studying high energy O2-O2 collisions and predicting collision induced dissociation cross section to be used in simulating non-equilibrium aerothermodynamic flows.

  1. New approach for strategic bidding of Gencos in energy and spinning reserve markets

    International Nuclear Information System (INIS)

    Soleymani, S.; Ranjbar, A.M.; Shirani, A.R.

    2007-01-01

    In restructured and de-regulated power systems, generating companies (Gencos) are responsible for supplying electricity for both energy and reserve markets, which usually operate simultaneously. In this condition, the question is how much and for what price must each Genco generate for each market to maximize its profit, so this paper intends to answer to this question. In this paper, first, the combined energy and reserve markets are considered, and the Nash equilibrium points are determined. Then, the bidding strategies for each Genco at these points will be presented. The bids for the energy and 10 min spinning reserve (TMSR) markets are separated in the second stage, and again, the bidding strategies for each Genco for the two separated markets will be demonstrated. Comparison of the results shows that the separated bidding strategies, while being simplified with the algebraic optimization model and reducing the time consumed, give the same results as the combined ones. The Western System Coordinating Council (WSCC) nine bus test system is employed to illustrate and verify the results of the proposed method

  2. Spin symposium

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1989-01-15

    The recent 8th International Symposium on High Energy Spin Physics at the University of Minnesota in Minneapolis, Minnesota, opened with a bang when L. Pondrom (Wisconsin), donning a hard hat borrowed from construction workers, ventured that 'spin, the notorious inessential complication of hadronic physics, is finally telling us what real QCD (quantum chromodynamics, the field theory of quarks and gluons) looks like.' He was referring to an animated discussion on the meaning of the recent spin oriented (polarized) scattering results from the European Muon Collaboration (EMC) at CERN and reported at the Symposium by R. Garnet (Liverpool) and P. Schuler (Yale) which show that the proton spin is not simply a reflection of the spins of its constituent quarks.

  3. Evaluation of excitation energy and spin in fission fragments using the statistical model, and the FIPPS project

    International Nuclear Information System (INIS)

    Faust, H.; Koester, U.; Kessedjian, G.; Sage, C.; Chebboubi, A.

    2013-01-01

    We review the statistical model and its application for the process of nuclear fission. The expressions for excitation energy and spin distributions for the individual fission fragments are given. We will finally emphasize the importance of measuring prompt gamma decay to further test the statistical model in nuclear fission with the FIPPS project. (authors)

  4. COSY Juelich - a cooler synchrotron for unpolarized and polarized medium-energy studies

    International Nuclear Information System (INIS)

    Seyfarth, H.

    2001-01-01

    Full text: The Forschungszentrum Juelich (Research Center Juelich) is one of the sixteen national research institutions in the 'Hermann von Helmholtz Association of German Research Centers'. It is dedicated to fundamental and applied research and development which can be summarized under five priorities: (i) structure of matter and materials research, (ii) information technology, (iii) life sciences, (iv) environment precaution research, and (v) energy technology. As one of the institutes within (i). the Institut fur Kernphysik (Institute for Nuclear Research) operates the COSY cooler synchrotron which allows to accelerate unpolarized and polarized protons and deuterons to the maximum momentum of 3450 MeV/c (2640 MeV and 2050 MeV kinetic energy for protons and deuterons, respectively). At low energy electron cooling can be used for beam preparation, whereas stochastic cooling can be applied to the accelerated beam. In the first years of operation since 1993 the experiments have been performed with the unpolarized proton beam. Since 1997 the polarized proton beam is available with increasing intensity and a typical degree of polarization of about 75 % up to the maximum beam energy. In 2000 the first unpolarized deuteron beam could be accelerated and stored at the maximum energy. Four target places exist for the internal experiments PISA. EDDA, COSY-II, and ANKE which use the circulating beam with thin solid strip or fiber targets and gas targets. The four experiments TOF, MOMO, GEM, NESSI, and JESSICA are using external beams. The programs of the experiments JESSICA (Juelich Experimental Spallation Setup in the COSY Area), NESSI (Neutron Scintillator and Silicon), and PISA (Proton Induced Spallation) aim at the measurement of data needed or the design of the target station of the planned European Spallation neutron Source (ESS). The set-up of PISA is replacing the earlier experiment COSY-13 which successfully completed its investigations on the production of

  5. Strain relaxation of CdTe on Ge studied by medium energy ion scattering

    Energy Technology Data Exchange (ETDEWEB)

    Pillet, J.C., E-mail: jean-christophe.pillet@cea.fr [Univ. Grenoble Alpes, CEA, LETI, MINATEC campus, F38000 Grenoble (France); CEA, LETI, Département Optique et Photonique, F38054 Grenoble (France); Pierre, F. [Univ. Grenoble Alpes, CEA, LETI, MINATEC campus, F38000 Grenoble (France); CEA, LETI, Service de Caractérisation des Matériaux et Composants, F38054 Grenoble (France); Jalabert, D. [Univ. Grenoble Alpes, CEA, LETI, MINATEC campus, F38000 Grenoble (France); CEA-INAC/UJF-Grenoble 1 UMR-E, SP2M, LEMMA, Minatec Grenoble F-38054 (France)

    2016-10-01

    We have used the medium energy ion scattering (MEIS) technique to assess the strain relaxation in molecular-beam epitaxial (MBE) grown CdTe (2 1 1)/Ge (2 1 1) system. A previous X-ray diffraction study, on 10 samples of the same heterostructure having thicknesses ranging from 25 nm to 10 μm has allowed the measurement of the strain relaxation on a large scale. However, the X-ray diffraction measurements cannot achieve a stress measurement in close proximity to the CdTe/Ge interface at the nanometer scale. Due to the huge lattice misfit between the CdTe and Ge, a high degree of disorder is expected at the interface. The MEIS in channeling mode is a good alternative in order to profile defects with a high depth resolution. For a 21 nm thick CdTe layer, we observed, at the interface, a high density of Cd and/or Te atoms moved from their expected crystallographic positions followed by a rapid recombination of defects. Strain relaxation mechanisms in the vicinity of the interface are discussed.

  6. Experimental Medium Energy Physics annual progress report, June 1984-May 1985

    International Nuclear Information System (INIS)

    1985-01-01

    During the past year the principal activities of the CMU Medium Energy Physics Group have included the running of three previously approved experiments, the development of hardware and software for these experiments, and final analysis of previously accumulated data. In a two week run at LEAR at the beginning of this year 100 data tapes were collected on experiment PS-185. This spring sigma hyperon production in Lithium was studied in a run on AGS experiment E-774. We are currently setting up AGS experiment E-788 in an investigation of Lambda weak decay in Helium hypernuclei. In addition a new experiment to search for strangeness S = -2 dibaryon production was presented and approved by the AGS program advisory committee for 1000 h (E-813). For these experiments extensive hardware and software development has taken place, requiring much of the group's effort. Analysis of LEAR experiment PS-185 is in full progress at CMU. Both the weak decay studies of 12 C (AGS E-759) and the pion annihilation studies in Lithium and Oxygen have now been fully analyzed with the results submitted for publication in several papers. All of these activities are described. Specific hardware and software projects are discussed

  7. Nuclear calculation for employing medium enrichment in reactors of Japan Atomic Energy Research Institute

    International Nuclear Information System (INIS)

    Miyasaka, Yasuhiko

    1979-01-01

    The fuel used for the research reactors of Japan Atomic Energy Research Institute (JAERI) is presently highly enriched uranium of 93%. However, the U.S. government (the supplier of fuel) is claiming to utilize low or medium enriched uranium from the viewpoint of resistivity to nuclear proliferation, and the availability of highly enriched uranium is becoming hard owing to the required procedure. This report is described on the results of nuclear calculation which is the basis of fuel design in the countermeasures to the reduction of enrichment. The basic conception in the reduction of enrichment is three-fold: to lower the latent potential of nuclear proliferation as far as possible, to hold the present reactor performance as far as possible, and to limit the reduction in the range which is not accompanied by the modification of reactor core construction and cooling system. This time, the increase of the density and thickness of fuel plates and the effect of enrichment change to 45% on reactivity and neutron flux were investigated. The fuel of UAl sub(x) - Al system was assumed, which was produced by powder metallurgical method. The results of investigations on JRR-2 and JMTR reactors revealed that 45% enriched fuel does not affect the performances much. However, deterioration of the performances is not neglegible if further reduction is needed. In future, the influence of the burn-up effect of fuel on the life of reactor cores must be investigated. (Wakatsuki, Y.)

  8. Energy metabolism of medium-chain triglycerides versus carbohydrates during exercise.

    Science.gov (United States)

    Décombaz, J; Arnaud, M J; Milon, H; Moesch, H; Philippossian, G; Thélin, A L; Howald, H

    1983-01-01

    Medium-chain triglycerides (MCT) are known to be rapidly digested and oxidized. Their potential value as a source of dietary energy during exercise was compared with that of maltodextrins (MD). Twelve subjects exercised for 1 h on a bicycle ergometer (60% VO2 max), 1 h after the test meal (1MJ). The metabolism of MCT was followed using 1-13C-octanoate (Oc) as tracer and U-13C-glucose (G) was added to the 13C-naturally enriched MD. After MCT ingestion no insulin peak was observed with some accumulation of ketone bodies (KB), blood levels not exceeding 1 mM. Total losses of KB during exercise in urine, sweat and as breath acetone were small (less than 0.2 mmol X h-1). Hence, the influence of KB loss and storage on gas exchange data was negligible. The partition of fat and carbohydrate utilization during exercise as obtained by indirect calorimetry was practically the same after the MCT and the CHO meals. Oxidation over the 2-h period was 30% of dose for Oc and 45% for G. Glycogen decrements in the Vastus lateralis muscle were equal. It appears that with normal carbohydrate stores, a single meal of MCT or CHO did not alter the contribution of carbohydrates during 1 h of high submaximal exercise. The moderate ketonemia after MCT, despite substantial oxidation of this fat, led to no difference in muscle glycogen sparing between the diets.

  9. Lattice design of medium energy beam transport line for n spallation neutron source

    International Nuclear Information System (INIS)

    Dhingra, Rinky; Kulkarni, Nita S.; Kumar, Vinit

    2015-01-01

    A 1 GeV H - injector linac is being designed at RRCAT for the proposed Indian Spallation Neutron Source (ISNS). The front-end of the injector linac will consist of Radiofrequency Quadrupole (RFQ) linac, which will accelerate the H - beam from 50 keV to 3 MeV. The beam will be further accelerated in superconducting Single Spoke Resonators (SSRs). A Medium Energy Beam Transport (MEBT) line will be used to transport the beam from the exit of RFQ to the input of SSR. The main purpose of MEBT is to carry out beam matching from RFQ to SSR, and beam chopping. In this paper, we describe the optimization criteria for the lattice design of MEBT. The optimized lattice element parameters are presented for zero and full (15 mA) current case. Beam dynamics studies have been carried out using an envelope tracing code Trace-3D. Required beam deflection angle due to the chopper housed inside the MEBT for beam chopping has also been estimated. (author)

  10. Experimental medium-energy physics. Annual progress report, June 1982-May 1983

    International Nuclear Information System (INIS)

    1983-01-01

    During the past year the principal activities of the C-MU Medium Energy Physics Group have included running of previously approved experiments, the development of hardware and software for new experiments, continued analysis of previously accumulated data, and the development of model calculations to be compared with these data. Major data runs have taken place on two hypernuclear experiments (AGS 759 and 760) at the AGS, and testing and running will soon begin at CERN/LEAR for our antiproton work (LEAR PS-185). For these experiments extensive hardware and software development has taken place, requiring much of the group's effort. This activity is described in detail. In our ongoing studies of the pion annihilation mechanism, the emphasis has shifted from two-body processes to those involving three-body final states. A large effort is being devoted to the analysis of our (π,pp), (π,pd) and pionic fission data accumulated at LAMPF on targets of 6 7 Li, 14 N, 16 O and CD 2 . During the past year we have also completed analysis of 800 MeV/c π scattering data from C and Ca nuclei, an experiment done simultaneously with our earlier kaon scattering measurement. In addition, considerable effort has been devoted to development of model calculations for the (π,2p) and anti pp → anti #betta# #betta# reactions; these are described

  11. Experimental medium energy physics. Annual progress report, June 1983-May 1984

    International Nuclear Information System (INIS)

    1984-01-01

    During the past year the principal activities of the C-MU Medium Energy Physics Group have included running of previously approved experiments, the development of hardware and software for new experiments, continued analysis of previously accumulated data, and the development of model calculations to be compared with these data. Major data runs have taken place on a hypernuclear experiment (AGS 781) at the AGS, and on an antiproton run at CERN/LEAR (PS-185). In addition, planning is continuing for further hypernuclear lifetime measurements in 4 5 He, and for a possible search for the H-particle. For these experiments extensive hardware and software development has taken place, requiring much of the group's effort. In our ongoing studies of the pion annihilation mechanism, the emphasis has shifted from two-body processes to those involving three-body final states. A large effort is being devoted to the analysis of our (π,xy) data accumulated at LAMPF on targets of 6 7 Li, 14 N, 16 O and CD 2 . During the year considerable effort was devoted to Monte Carlo simulations of the rare weak decay K + → π + nu anti nu; this experiment has been approved as AGS 787. In addition, work has continued on the development of model calculations of the (π,pp) and anti pp → anti ΛΛ reactions

  12. Quantitative considerations in medium energy ion scattering depth profiling analysis of nanolayers

    Energy Technology Data Exchange (ETDEWEB)

    Zalm, P.C.; Bailey, P. [International Institute for Accelerator Applications, University of Huddersfield, Queensgate, Huddersfield HD1 3DH (United Kingdom); Reading, M.A. [Physics and Materials Research Centre, University of Salford, Salford M5 4WT (United Kingdom); Rossall, A.K. [International Institute for Accelerator Applications, University of Huddersfield, Queensgate, Huddersfield HD1 3DH (United Kingdom); Berg, J.A. van den, E-mail: j.vandenberg@hud.ac.uk [International Institute for Accelerator Applications, University of Huddersfield, Queensgate, Huddersfield HD1 3DH (United Kingdom)

    2016-11-15

    The high depth resolution capability of medium energy ion scattering (MEIS) is becoming increasingly relevant to the characterisation of nanolayers in e.g. microelectronics. In this paper we examine the attainable quantitative accuracy of MEIS depth profiling. Transparent but reliable analytical calculations are used to illustrate what can ultimately be achieved for dilute impurities in a silicon matrix and the significant element-dependence of the depth scale, for instance, is illustrated this way. Furthermore, the signal intensity-to-concentration conversion and its dependence on the depth of scattering is addressed. Notably, deviations from the Rutherford scattering cross section due to screening effects resulting in a non-coulombic interaction potential and the reduction of the yield owing to neutralization of the exiting, backscattered H{sup +} and He{sup +} projectiles are evaluated. The former mainly affects the scattering off heavy target atoms while the latter is most severe for scattering off light target atoms and can be less accurately predicted. However, a pragmatic approach employing an extensive data set of measured ion fractions for both H{sup +} and He{sup +} ions scattered off a range of surfaces, allows its parameterization. This has enabled the combination of both effects, which provides essential information regarding the yield dependence both on the projectile energy and the mass of the scattering atom. Although, absolute quantification, especially when using He{sup +}, may not always be achievable, relative quantification in which the sum of all species in a layer adds up to 100%, is generally possible. This conclusion is supported by the provision of some examples of MEIS derived depth profiles of nanolayers. Finally, the relative benefits of either using H{sup +} or He{sup +} ions are briefly considered.

  13. High resolution medium energy ion scattering study of silicon oxidation and oxy nitridation

    International Nuclear Information System (INIS)

    Gusev, E.P.; Lu, H.C.; Garfunkel, E.; Gustafsson, T.

    1998-01-01

    Full text: Silicon oxide is likely to remain the material of choice for gate oxides in microelectronics for the foreseeable future. As device become ever smaller and faster, the thickness of these layers in commercial products is predicted to be less than 50 Angstroms in just a few years. An understanding of such devices will therefore likely to be based on microscopic concepts and should now be investigated by atomistic techniques. With medium energy ion scattering (MEIS) using an electrostatic energy analyzer, depth profiling of thin (<60 Angstroms) silicon oxide films on Si(100) with 3 - 5 Angstroms depth resolution in the near region has been done. The growth mechanism of thin oxide films on Si(100) has been studied, using sequential oxygen isotope exposures. It is found that the oxide films are stoichiometric to within approx. 10 Angstroms of the interface. It is also found that the oxidation reactions occur at the surface, in the transition region and at interface, with only the third region being included in the conventional (Deal-Grove) model for oxide formation. Nitrogen is sometimes added to gate oxides, as it has been found empirically that his improves some of the electrical properties. The role, location and even the amount of nitrogen that exists in such films are poorly understood, and represent interesting analytical challenges. MEIS data will be presented that address these questions, measured for a number of different processing conditions. We have recently demonstrated how to perform nitrogen nano-engineering in such ultrathin gate dielectrics, and these results will also be discussed

  14. Experimental medium energy physics: Annual progress report, June 1986-May 1987

    International Nuclear Information System (INIS)

    1987-01-01

    During the past year the Carnegie Mellon University (CMU) Medium Energy Physics Group activities included five experimental programs, each at different stages of development. The analyses of data from two previous experiments were completed over the last year; a recent doctoral thesis represents a milestone in our study of the weak decays of hypernuclei. Software and hardware support was continued and data analysis initiated for the two experiments which received running time during this period. The status of the H dibaryon search proposals changed from conditional approval to full approval when funds were allocated for the new kaon beam line required for the experiments. The measurements of anti ΛΛ production at LEAR (PS-185) have been completed. A study of the polarization and angular distributions near threshold have been submitted for publication and an analysis of a CP test of the decay asymmetry parameters is complete. Results of data taken last year are being finalized. The analysis of data on the decay of 5 /sub Λ/He (AGS E-788) taken at BNL has also been completed in the past year and a publication is in preparation. Last summer the focus of the PS185 collaboration shifted from anti ΛΛ to a search for evidence of the ξ(2230) using the anti pp → K/sub s/K/sub s/ channel. Modifications designed to increase the acceptance of the LEAR anti ΛΛ experimental apparatus for this reaction were completed and a scan of the energy region near 2230 MeV took place in August. The data from this experiment are being analyzed at CMU. The CMU group has had extensive involvement in an experiment to search for strangeness production relativistic heavy ion collisions (CERN NA36). CMU personnel have installed computer hardware and worked on the development of new software designed for the on-line monitoring. The work was completed in time for the first running of the experiment in November of 1986

  15. Design and Simulation of a Spin Rotator for Longitudinal Field Measurements in the Low Energy Muons Spectrometer

    Science.gov (United States)

    Salman, Z.; Prokscha, T.; Keller, P.; Morenzoni, E.; Saadaoui, H.; Sedlak, K.; Shiroka, T.; Sidorov, S.; Suter, A.; Vrankovic, V.; Weber, H.-P.

    We usedGeant4 to accurately model the low energy muons (LEM) beam line, including scattering due to the 10-nm thin carbon foil in the trigger detector. Simulations of the beam line transmission give excellent agreement with experimental results for beam energies higher than ∼ 12keV.We use these simulations to design and model the operation of a spin rotator for the LEM spectrometer, which will enable longitudinal field measurements in the near future.

  16. Stable, metastable and unstable solutions of a spin-1 Ising system based on the free energy surfaces

    Science.gov (United States)

    Keskİin, Mustafa; Özgan, Şükrü

    1990-04-01

    Stable, metastable and unstable solutions of a spin-1 Ising model with bilinear and biquadratic interactions are found by using the free energy surfaces. The free energy expression is obtained in the lowest approximation of the cluster variation method. All these solutions are shown in the two-dimensional phase space, especially the unstable solutions which in some cases are difficult to illustrate in the two-dimensional phase space, found by Keskin et al. recently.

  17. Advertisement-Based Energy Efficient Medium Access Protocols for Wireless Sensor Networks

    Science.gov (United States)

    Ray, Surjya Sarathi

    One of the main challenges that prevents the large-scale deployment of Wireless Sensor Networks (WSNs) is providing the applications with the required quality of service (QoS) given the sensor nodes' limited energy supplies. WSNs are an important tool in supporting applications ranging from environmental and industrial monitoring, to battlefield surveillance and traffic control, among others. Most of these applications require sensors to function for long periods of time without human intervention and without battery replacement. Therefore, energy conservation is one of the main goals for protocols for WSNs. Energy conservation can be performed in different layers of the protocol stack. In particular, as the medium access control (MAC) layer can access and control the radio directly, large energy savings is possible through intelligent MAC protocol design. To maximize the network lifetime, MAC protocols for WSNs aim to minimize idle listening of the sensor nodes, packet collisions, and overhearing. Several approaches such as duty cycling and low power listening have been proposed at the MAC layer to achieve energy efficiency. In this thesis, I explore the possibility of further energy savings through the advertisement of data packets in the MAC layer. In the first part of my research, I propose Advertisement-MAC or ADV-MAC, a new MAC protocol for WSNs that utilizes the concept of advertising for data contention. This technique lets nodes listen dynamically to any desired transmission and sleep during transmissions not of interest. This minimizes the energy lost in idle listening and overhearing while maintaining an adaptive duty cycle to handle variable loads. Additionally, ADV-MAC enables energy efficient MAC-level multicasting. An analytical model for the packet delivery ratio and the energy consumption of the protocol is also proposed. The analytical model is verified with simulations and is used to choose an optimal value of the advertisement period

  18. Photon energy dependence of photo-induced inverse spin-Hall effect in Pt/GaAs and Pt/Ge

    Energy Technology Data Exchange (ETDEWEB)

    Isella, Giovanni, E-mail: giovanni.isella@polimi.it; Bottegoni, Federico; Ferrari, Alberto; Finazzi, Marco; Ciccacci, Franco [LNESS-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)

    2015-06-08

    We report the photon energy dependence of photo-induced inverse spin Hall effect (ISHE) in Pt/GaAs and Pt/Ge Schottky junctions. The experimental results are compared with a spin drift-diffusion model, which highlights the role played by the different spin lifetime in the two semiconductors, in determining the energy dependence of the ISHE signal detected in the Pt layer. The good qualitative agreement between experiments and modelling indicates that photo-induced ISHE can be used as a tool to characterize spin lifetime in semiconductors.

  19. Feasibility study analysis for multi-function dual energy oven (case study: tapioca crackers small medium enterprise)

    Science.gov (United States)

    Soraya, N. W.; El Hadi, R. M.; Chumaidiyah, E.; Tripiawan, W.

    2017-12-01

    Conventional drying process is constrained by weather (cloudy / rainy), and requires wide drying area, and provides low-quality product. Multi-function dual energy oven is the appropriate technology to solve these problems. The oven uses solar thermal or gas heat for drying various type of products, including tapioca crackers. Investment analysis in technical, operational, and financial aspects show that the multi-function dual energy oven is feasible to be implemented for small medium enterprise (SME) processing tapioca crackers.

  20. Emission of medium-heavy fragments in asymetric heavy ion collisions at intermediate and relativistic incident energies

    International Nuclear Information System (INIS)

    Milkau, T.U.E.

    1991-11-01

    For the study of the emission of medium-heavy fragments in asymmetric heavy ion collisions a series of experiments was performed and thereby following systems at intermediate and relativistic incident energies studied: 84 Kr+ 197 Au at E/A=35 MeV, 40 Ar+ 197 Au at E/A=30 MeV, respectively 220 MeV, and 12 C+ 197 Au at E/A=99 MeV, 301 MeV, 601 MeV, respectively 1105 MeV. In the experiments highly resolving detector telescopes with low thresholds were applied to the measurement of the energy and angular distributions of the medium-heavy fragments. The spectra were analyzed in the picture of longitudinally moving sources. Thereby beyond the production cross sections the angular distributions, the decreasement parameters in the high-energetic region of the energy spectra, and the position of the maxima were determined as characteristic parameters. The following picture resulted: The production cross sections for medium-heavy fragments showed a steep increasement and then a saturation, but with a strong projectile dependence. The charge distributions could be described by a power law, the parameter of which showed a universal dependence on the total incident energy. In the angular distributions the transition from an anisotropic emission at low energies to an isotropic emission from a nearly resting source at relativistic energies was distinctly to be recognized. The decreasement parameters of the energy distribution increased - for different projectiles differently strongly - logarithmically with growing incident energy. And the maxima of the energy distribution travelled with growing incident energy to smaller and smaller fragment energies. From this systematics a schematic model of the fragmentation can be obtained. (orig./HSI) [de

  1. Spin Conference

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The 5th International Symposium on High Energy Spin Physics met in September at Brookhaven. The symposium has evolved to include a number of diverse specialities: theory, including parity violations and proposed quantum chromodynamics (QCD) tests with polarized beams; experiment, including the large spin effects discovered in high transverse momentum elastic scattering and hyperon production, dibaryons, and magnetic moments; acceleration and storage of polarized protons and electrons; and development of polarized sources and targets

  2. Achieving 99.9% proton spin-flip efficiency at higher energy with a small rf dipole

    CERN Document Server

    Leonova, M A; Gebel, R; Hinterberger, F; Krisch, A D; Lehrach, A; Lorentz, B; Maier, R; Morozov, V S; Prasuhn, D; Raymond, R S; Schnase, A; Stockhorst, H; Ulbrich, K; Wong, V K; 10.1103/PhysRevLett.93.224801

    2004-01-01

    We recently used a new ferrite rf dipole to study spin flipping of a 2.1 GeV/c vertically polarized proton beam stored in the COSY Cooler Synchrotron in Julich, Germany. We swept the rf dipole's frequency through an rf-induced spin resonance to flip the beam's polarization direction. After determining the resonance's frequency, we varied the frequency range, frequency ramp time, and number of flips. At the rf dipole's maximum strength and optimum frequency range and ramp time, we measured a spin-flip efficiency of 99.92+or-0.04%. This result, along with a similar 0.49 GeV/c IUCF result, indicates that, due to the Lorentz invariance of an rf dipole's transverse integral Bdl and the weak energy dependence of its spin-resonance strength, an only 35% stronger rf dipole should allow efficient spin flipping in the 100 GeV BNL RHIC Collider or even the 7 TeV CERN Large Hadron Collider.

  3. Large spin limit of AdS5xS5 string theory and low energy expansion of ferromagnetic spin chains

    International Nuclear Information System (INIS)

    Kruczenski, M.; Ryzhov, A.V.; Tseytlin, A.A.

    2004-01-01

    By considering AdS 5 xS 5 string states with large S 5 angular momenta one can provide non-trivial quantitative checks of the AdS/CFT duality. A string rotating in S 5 with two angular momenta J 1 , J 2 is dual to an operator in N=4 SYM theory whose conformal dimension can be computed by diagonalizing a (generalization of) spin 1/2 Heisenberg chain Hamiltonian. It was recently argued and verified to lowest order in a large J=J 1 +J 2 expansion, that the Heisenberg chain can be described using a non-relativistic low energy effective 2d action for a unit vector field n i which exactly matches the corresponding large J limit of the classical AdS 5 xS 5 string action. In this paper we show that this agreement extends to the next order and develop a systematic procedure for computing higher orders in such large angular momentum expansion. This involves several non-trivial steps. On the string side, we need to choose a special gauge with a non-diagonal world-sheet metric which insures that the angular momentum is uniformly distributed along the string, as indeed is the case on the spin chain side. We need also to implement an order by order redefinition of the field n i to get an action linear in the time derivative. On the spin chain side, it turns out to be crucial to include the effects of integrating out short wave-length modes. In this way we gain a better understanding of how (a subsector of) the string sigma model emerges from the dual gauge theory, allowing us to demonstrate the duality beyond comparing particular examples of states with large J

  4. Electron--noble-gas spin-flip scattering at low energy

    International Nuclear Information System (INIS)

    Walker, T.G.; Bonin, K.; Happer, W.

    1987-01-01

    The spin-exchange rates and spin-relaxation rates for thermal electrons colliding with noble-gas atoms are calculated using the orthogonalized-plane-wave approximation and via partial-wave analysis. The two techniques give similar results and are in order-of-magnitude agreement with the experimental rate in Ar

  5. Beam and spin dynamics of hadron beams in intermediate-energy ring accelerators

    International Nuclear Information System (INIS)

    Lehrach, Andreas

    2008-01-01

    In this thesis beam and spin dynamics of ring accelerators are described. After a general theoretical treatment methods for the beam optimization and polarization conservation are discussed. Then experiments on spin manipulation at the COSY facility are considered. Finally the beam simulation and accelerator lay-out for the HESR with regards to the FAIR experiment are described. (HSI)

  6. Spin-polarized high-energy scattering of charged leptons on nucleons

    Energy Technology Data Exchange (ETDEWEB)

    Burkardt, Matthias; Nowak, Wolf-Dieter; MILLER, A.

    2009-01-01

    The proton is a composite object with spin one-half, understood to contain highly relativistic spin one-half quarks exchanging spin-one gluons, each possibly with significant orbital angular momenta. While their fundamental interactions are well described by Quantum ChromoDynamics (QCD), our standard theory of the strong interaction, nonperturbative calculations of the internal structure of the proton based directly on QCD are beginning to provide reliable results. Most of our present knowledge of the structure of the proton is based on experimental measurements interpreted within the rich framework of QCD. An area presently attracting intense interest, both experimental and theoretical, is the relationship between the spin of the proton and the spins and orbital angular momenta of its constituents. While remarkable progress has been made, especially in the last decade, the discovery and investigation of new concepts have revealed that much more remains to be learned. This progress i

  7. Local governments and climate change: sustainable energy planning and implementation in small and medium sized communities

    National Research Council Canada - National Science Library

    Van Staden, Maryke; Musco, Francesco

    2010-01-01

    The focus of 'Local governments and climate change' is on how small and medium-sized communities in Europe are effectively responding to climate change, with a particular focus on different approaches...

  8. Spinning Eggs and Ballerinas

    Science.gov (United States)

    Cross, Rod

    2013-01-01

    Measurements are presented on the rise of a spinning egg. It was found that the spin, the angular momentum and the kinetic energy all decrease as the egg rises, unlike the case of a ballerina who can increase her spin and kinetic energy by reducing her moment of inertia. The observed effects can be explained, in part, in terms of rolling friction…

  9. Measurements of the spin rotation parameter R in high energy elastic scattering and helicity amplitudes at Serpukhov energies

    International Nuclear Information System (INIS)

    Pierrard, J.; Bruneton, C.; Bystricky, J.; Cozzika, G.; Deregel, J.; Ducros, Y.; Gaidot, A.; Khantine-Langlois, F.; Lehar, F.; Lesquen, A. de; Merlo, J.P.; Miyashita, S.; Movchet, J.; Raoul, J.C.; Van Rossum, L.; Kanavets, V.P.

    1975-01-01

    The spin rotation parameter R in pp and π + p elastic scattering at 45GeV/c has been measured at the Serpukhov accelerator, for /t/ ranging from 0.2 to 0.5(GeV/c) 2 . The results are presented, together with previous R measurements at 3.8, 6, 16 and 40GeV/c, and are compared with the predictions of Regge pole models. The equality of the values for R in proton-proton and pion-proton scattering, within the experimental errors, is a test of factorization of the residues. An s-channel helicity amplitude analysis for pion-nucleon scattering at 40GeV/c is made using all available data. Significant results are obtained for the non flip amplitude in isoscalar exchange and for flip amplitudes on both isovector and isoscalar exchanges. The helicity flip in isoscalar exchange is non negligible. The energy dependence of this amplitude, at 6, 16 and 40GeV/c, is compared with predictions of Regge pole models [fr

  10. Self-spinning nanoparticle laden microdroplets for sensing and energy harvesting.

    Science.gov (United States)

    Bhattacharjee, Mitradip; Pasumarthi, Viswanath; Chaudhuri, Joydip; Singh, Amit Kumar; Nemade, Harshal; Bandyopadhyay, Dipankar

    2016-03-21

    Exposure of a volatile organic vapour could set in powerful rotational motion a microdroplet composed of an aqueous salt solution loaded with metal nanoparticles. The solutal Marangoni motion on the surface originating from the sharp difference in the surface tension of water and organic vapour stimulated the strong vortices inside the droplet. The vapour sources of methanol, ethanol, diethyl ether, toluene, and chloroform stimulated motions of different magnitudes could easily be correlated to the surface tension gradient on the drop surface. Interestingly, when the nanoparticle laden droplet of aqueous salt solution was connected to an external electric circuit through a pair of electrodes, an ∼85-95% reduction in the electrical resistance was observed across the spinning droplet. The extent of reduction in the resistance was found to have a correlation with the difference in the surface tension of the vapour source and the water droplet, which could be employed to distinguish the vapour sources. Remarkably, the power density of the same prototype was estimated to be around 7 μW cm(-2), which indicated the potential of the phenomenon in converting surface energy into electrical in a non-destructive manner and under ambient conditions. Theoretical analysis uncovered that the difference in the ζ-potential near the electrodes was the major reason for the voltage generation. The prototype could also detect the repeated exposure and withdrawal of vapour sources, which helped in the development of a proof-of-concept detector to sense alcohol issuing out of the human breathing system.

  11. Investigation of the energy-averaged double transition density of isoscalar monopole excitations in medium-heavy mass spherical nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Gorelik, M.L.; Shlomo, S. [National Research Nuclear University “MEPhI”, Moscow 115409 (Russian Federation); Cyclotron Institute, Texas A& M University, College Station, TX 77843 (United States); Tulupov, B.A. [National Research Nuclear University “MEPhI”, Moscow 115409 (Russian Federation); Institute for Nuclear Research, RAS, Moscow 117312 (Russian Federation); Urin, M.H., E-mail: urin@theor.mephi.ru [National Research Nuclear University “MEPhI”, Moscow 115409 (Russian Federation)

    2016-11-15

    The particle–hole dispersive optical model, developed recently, is applied to study properties of high-energy isoscalar monopole excitations in medium-heavy mass spherical nuclei. The energy-averaged strength functions of the isoscalar giant monopole resonance and its overtone in {sup 208}Pb are analyzed. In particular, we analyze the energy-averaged isoscalar monopole double transition density, the key quantity in the description of the hadron–nucleus inelastic scattering, and studied the validity of the factorization approximation using semi classical and microscopic one body transition densities, respectively, in calculating the cross sections for the excitation of isoscalar giant resonances by inelastic alpha scattering.

  12. Development of the Advanced Energetic Pair Telescope (AdEPT) for Medium-Energy Gamma-Ray Astronomy

    Science.gov (United States)

    Hunter, Stanley D.; Bloser, Peter F.; Dion, Michael P.; McConnell, Mark L.; deNolfo, Georgia A.; Son, Seunghee; Ryan, James M.; Stecker, Floyd W.

    2011-01-01

    Progress in high-energy gamma-ray science has been dramatic since the launch of INTEGRAL, AGILE and FERMI. These instruments, however, are not optimized for observations in the medium-energy (approx.0.3< E(sub gamma)< approx.200 MeV) regime where many astrophysical objects exhibit unique, transitory behavior, such as spectral breaks, bursts, and flares. We outline some of the major science goals of a medium-energy mission. These science goals are best achieved with a combination of two telescopes, a Compton telescope and a pair telescope, optimized to provide significant improvements in angular resolution and sensitivity. In this paper we describe the design of the Advanced Energetic Pair Telescope (AdEPT) based on the Three-Dimensional Track Imager (3-DTI) detector. This technology achieves excellent, medium-energy sensitivity, angular resolution near the kinematic limit, and gamma-ray polarization sensitivity, by high resolution 3-D electron tracking. We describe the performance of a 30x30x30 cm3 prototype of the AdEPT instrument.

  13. Nuclear spin and isospin excitations

    International Nuclear Information System (INIS)

    Osterfeld, F.

    1992-01-01

    A review is given of our present knowledge of collective spin-isospin excitations in nuclei. Most of this knowledge comes from intermediate-energy charge-exchange reactions and from inelastic electron- and proton-scattering experiments. The nuclear-spin dynamics is governed by the spin-isospin-dependent two-nucleon interaction in the medium. This interaction gives rise to collective spin modes such as the giant Gamow-Teller resonances. An interesting phenomenon is that the measured total Gamow-Teller transition strength in the resonance region is much less than a model-independent sum rule predicts. Two physically different mechanisms have been discussed to explain this so-called quenching of the total Gamow-Teller strength: coupling to subnuclear degrees of freedom in the form of Δ-isobar excitation and ordinary nuclear configuration mixing. Both detailed nuclear structure calculations and extensive analyses of the scattering data suggest that the nuclear configuration mixing effect is the more important quenching mechanism, although subnuclear degrees of freedom cannot be ruled out. The quenching phenomenon occurs for nuclear-spin excitations at low excitation energies (ω∼10--20 MeV) and small-momentum transfers (q≤0.5 fm -1 ). A completely opposite effect is anticipated in the high (ω,q)-transfer region (0≤ω≤500 MeV, 0.5≤q≤3 fm -1 ). The nuclear spin-isospin response might be enhanced due to the attractive pion field inside the nucleus. Charge-exchange reactions at GeV incident energies have been used to study the quasifree peak region and the Δ-resonance region. An interesting result of these experiments is that the Δ excitation in the nucleus is shifted downwards in energy relative to the Δ excitation of the free proton

  14. New Topological Configurations in the Continuous Heisenberg Spin Chain: Lower Bound for the Energy

    Directory of Open Access Journals (Sweden)

    Rossen Dandoloff

    2015-01-01

    Full Text Available In order to study the spin configurations of the classical one-dimensional Heisenberg model, we map the normalized unit vector, representing the spin, on a space curve. We show that the total chirality of the configuration is a conserved quantity. If, for example, one end of the space curve is rotated by an angle of 2π relative to the other, the Frenet frame traces out a noncontractible loop in SO(3 and this defines a new class of topological spin configurations for the Heisenberg model.

  15. The dosimetric standards for low and medium energy X-rays; Les references dosimetriques pour les rayons X de basses et moyennes energies

    Energy Technology Data Exchange (ETDEWEB)

    Ksouri, W.; Denoziere, M.; Lecerf, N.; Leroy, E.

    2009-07-01

    The Laboratoire national Henri Becquerel (LNE-LNHB) has developed national dosimetric standards for x-rays of low and medium energies. This article describes these standards which are aimed at applications of radiation protection of workers and patients in the fields of medical diagnosis and industrial x-ray radiation. Developments for contact radiotherapy are also discussed. (author)

  16. Spin-1/2 particles in non-inertial reference frames. Low- and high-energy approximations

    International Nuclear Information System (INIS)

    Singh, D.; Papini, G.

    2000-01-01

    Spin-1/2 particles can be used to study inertial and gravitational effects by means of interferometers, particle accelerators, and ultimately quantum systems. These studies require, in general, knowledge of the Hamiltonian and of the inertial and gravitational quantum phases. The procedure followed gives both in the low- and high-energy approximations. The latter affords a more consistent treatment of mass at high energies. The procedure is based on general relativity and on a solution of the Dirac equation that is exact to first-order in the metric deviation. Several previously known acceleration- and rotation-induced effects are rederived in a comprehensive, unified way. Several new effects involve spin, electromagnetic and inertial/gravitational fields in different combinations

  17. Low energy spin dynamics of rare-earth orthoferrites YFeO3 and LaFeO3

    Science.gov (United States)

    Park, Kisoo; Sim, Hasung; Leiner, Jonathan; Yoshida, Yoshiyuki; Eisaki, Hiroshi; Yano, Shinichiro; Gardner, Jason; Park, Je-Geun

    YFeO3 and LaFeO3\\ are members of the rare-earth orthoferrites (RFeO3) family with Pbnm space group. With the strong superexchange interaction between Fe3 + ions, both compounds exhibit the room temperature antiferromagnetic order (TN >600 K) with a slight spin canting. Here we report low-energy magnetic excitation of YFeO3 and LaFeO3 using inelastic neutron scattering measurements, showing evidence of magnon mode splitting and a spin anisotropy gap at the zone center. Spin wave calculations with the spin Hamiltonian including both Dzyaloshinsky-Moriya interaction and single-ion anisotropy accounts for the observed features well. Our results offer insight into the underlying physics of other RFeO3\\ with magnetic rare-earth ions or related Fe3+-based multiferroic perovskites such as BiFeO3. The work at the IBS CCES (South Korea) was supported by the research program of the Institute for Basic Science (IBS-R009-G1).

  18. Design and commissioning of an aberration-corrected ultrafast spin-polarized low energy electron microscope with multiple electron sources.

    Science.gov (United States)

    Wan, Weishi; Yu, Lei; Zhu, Lin; Yang, Xiaodong; Wei, Zheng; Liu, Jefferson Zhe; Feng, Jun; Kunze, Kai; Schaff, Oliver; Tromp, Ruud; Tang, Wen-Xin

    2017-03-01

    We describe the design and commissioning of a novel aberration-corrected low energy electron microscope (AC-LEEM). A third magnetic prism array (MPA) is added to the standard AC-LEEM with two prism arrays, allowing the incorporation of an ultrafast spin-polarized electron source alongside the standard cold field emission electron source, without degrading spatial resolution. The high degree of symmetries of the AC-LEEM are utilized while we design the electron optics of the ultrafast spin-polarized electron source, so as to minimize the deleterious effect of time broadening, while maintaining full control of electron spin. A spatial resolution of 2nm and temporal resolution of 10ps (ps) are expected in the future time resolved aberration-corrected spin-polarized LEEM (TR-AC-SPLEEM). The commissioning of the three-prism AC-LEEM has been successfully finished with the cold field emission source, with a spatial resolution below 2nm. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Self-spinning nanoparticle laden microdroplets for sensing and energy harvesting

    Science.gov (United States)

    Bhattacharjee, Mitradip; Pasumarthi, Viswanath; Chaudhuri, Joydip; Singh, Amit Kumar; Nemade, Harshal; Bandyopadhyay, Dipankar

    2016-03-01

    Exposure of a volatile organic vapour could set in powerful rotational motion a microdroplet composed of an aqueous salt solution loaded with metal nanoparticles. The solutal Marangoni motion on the surface originating from the sharp difference in the surface tension of water and organic vapour stimulated the strong vortices inside the droplet. The vapour sources of methanol, ethanol, diethyl ether, toluene, and chloroform stimulated motions of different magnitudes could easily be correlated to the surface tension gradient on the drop surface. Interestingly, when the nanoparticle laden droplet of aqueous salt solution was connected to an external electric circuit through a pair of electrodes, an ~85-95% reduction in the electrical resistance was observed across the spinning droplet. The extent of reduction in the resistance was found to have a correlation with the difference in the surface tension of the vapour source and the water droplet, which could be employed to distinguish the vapour sources. Remarkably, the power density of the same prototype was estimated to be around 7 μW cm-2, which indicated the potential of the phenomenon in converting surface energy into electrical in a non-destructive manner and under ambient conditions. Theoretical analysis uncovered that the difference in the ζ-potential near the electrodes was the major reason for the voltage generation. The prototype could also detect the repeated exposure and withdrawal of vapour sources, which helped in the development of a proof-of-concept detector to sense alcohol issuing out of the human breathing system.Exposure of a volatile organic vapour could set in powerful rotational motion a microdroplet composed of an aqueous salt solution loaded with metal nanoparticles. The solutal Marangoni motion on the surface originating from the sharp difference in the surface tension of water and organic vapour stimulated the strong vortices inside the droplet. The vapour sources of methanol, ethanol

  20. Design Aspects of An Energy-Efficient, Lightweight Medium Access Control Protocol for Wireless Sensor Networks

    NARCIS (Netherlands)

    van Hoesel, L.F.W.; Havinga, Paul J.M.

    2006-01-01

    This document gives an overview of the most relevant design aspects of the lightweight medium access control (LMAC) protocol [16] for wireless sensor networks (WSNs). These aspects include selfconfiguring and localized operation of the protocol, time synchronization in multi-hop networks, network

  1. The role of small and medium reactors in the energy security of a country, IRIS example

    International Nuclear Information System (INIS)

    Cavlina, N.

    2010-01-01

    Nuclear options for electricity generations are assessed in this paper. Probabilistic (stochastic) method is used for economic comparison of nuclear power plants, wind plants and natural gas fired plants. Optimal nuclear power plant size is also discussed. IRIS is presented as a representative of small and medium reactors

  2. Forster resonance energy transfer rate in any dielectric nanophotonic medium with weak dispersion

    DEFF Research Database (Denmark)

    Wubs, Martijn; Vos, Willem L.

    2016-01-01

    frequency dependent in nanophotonic media. Therefore, the position-dependent FRET rate and the LDOS at the donor transition frequency are completely uncorrelated for any nondispersive medium. Secondly, we derive an exact expression for the FRET rate as a frequency integral of the imaginary part of the Green...

  3. Lowest-energy cage structures of medium-sized (ZnO){sub n} clusters with n = 15 − 24

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lingli; Sai, Linwei [School of Mathematical Sciences, Dalian University of Technology, Dalian 116024, China and College of Advanced Science and Technology, Dalian University of Technology, Dalian 116024 (China); Zhao, Jijun, E-mail: zhaojj@dlut.edu.cn [College of Advanced Science and Technology, Dalian University of Technology, Dalian 116024, China and Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024 (China); Qiu, Ruifeng [School of Mathematical Sciences, Dalian University of Technology, Dalian 116024 (China)

    2015-01-22

    Fullerene-like cage structures of medium-sized (ZnO){sub n} clusters with n = 15 − 24 were generated by spiral algorithm and optimized using density functional theory calculations. Most of these lowest-energy cage structures contain only four-membered and six-membered rings, whereas eight-membered rings were found in the lowest-energy cages of (ZnO){sub n} (n = 19, 20, 23, 24). Our best cage configurations either reproduce or prevail the previously reported ones. The size-dependent electronic properties were also discussed.

  4. The energy-level crossing behavior and quantum Fisher information in a quantum well with spin-orbit coupling

    Science.gov (United States)

    Wang, Z. H.; Zheng, Q.; Wang, Xiaoguang; Li, Yong

    2016-03-01

    We study the energy-level crossing behavior in a two-dimensional quantum well with the Rashba and Dresselhaus spin-orbit couplings (SOCs). By mapping the SOC Hamiltonian onto an anisotropic Rabi model, we obtain the approximate ground state and its quantum Fisher information (QFI) via performing a unitary transformation. We find that the energy-level crossing can occur in the quantum well system within the available parameters rather than in cavity and circuit quantum eletrodynamics systems. Furthermore, the influence of two kinds of SOCs on the QFI is investigated and an intuitive explanation from the viewpoint of the stationary perturbation theory is given.

  5. Low-energy spin fluctuations in the non-Fermi-liquid compound YbRh2Si2

    Directory of Open Access Journals (Sweden)

    O. Stockert et al

    2007-01-01

    Full Text Available We report on inelastic neutron scattering experiments on YbRh2Si2 powder to study the low-energy spin dynamics at temperatures between T=0.8 and 22 K. The low-energy magnetic response is quasielastic. However, it exhibits an unusual form not modelled by a simple relaxation rate yielding a Lorentzian lineshape, but can satisfactorily be described by a phenomenological model involving a distribution of relaxation rates. The lower bound of the relaxation rates varies roughly linear with temperature indicating a pronounced slowing down of the critical modes above the antiferromagnetic ordering temperature TNapprox70 mK.

  6. In-medium and isospin effects on eta production in heavy-ion collisions near threshold energies

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jie; Chen, Peng-Hui [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); University of Chinese Academy of Sciences, Beijing (China); Feng, Zhao-Qing; Wang, Jian-Song [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Niu, Fei [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Henan Normal University, Institute of Particle and Nuclear Physics, Xinxiang (China); Guo, Ya-Fei [Chinese Academy of Sciences, Institute of Modern Physics, Lanzhou (China); Lanzhou University, School of Nuclear Science and Technology, Lanzhou (China)

    2017-06-15

    The dynamics of η meson produced in heavy-ion collisions has been investigated within the Lanzhou quantum molecular dynamics model (LQMD). The in-medium corrections have been considered in the model, in which an attractive η-nucleon potential is implemented. The impacts of the η optical potential and the nuclear symmetry energy on the η dynamics are investigated. It is found that the total yields are slightly influenced by the potential and weakly depend on the symmetry energy. However, the structure of the kinetic spectra is related to the optical potential and the stiffness of symmetry energy. The attractive potential leads to the reduction of high-momentum (kinetic energy) η production, i.e., the spectra of momentum and transverse mass distributions, increasing the reabsorption process by surrounding nucleons, and favoring the in-plane eta emissions. The reabsorption process in η-nucleon collisions plays a significant role on the η dynamics. (orig.)

  7. Carbon footprint analysis as a tool for energy and environmental management in small and medium-sized enterprises

    Science.gov (United States)

    Giama, E.; Papadopoulos, A. M.

    2018-01-01

    The reduction of carbon emissions has become a top priority in the decision-making process for governments and companies, the strict European legislation framework being a major driving force behind this effort. On the other hand, many companies face difficulties in estimating their footprint and in linking the results derived from environmental evaluation processes with an integrated energy management strategy, which will eventually lead to energy-efficient and cost-effective solutions. The paper highlights the need of companies to establish integrated environmental management practices, with tools such as carbon footprint analysis to monitor the energy performance of production processes. Concepts and methods are analysed, and selected indicators are presented by means of benchmarking, monitoring and reporting the results in order to be used effectively from the companies. The study is based on data from more than 90 Greek small and medium enterprises, followed by a comprehensive discussion of cost-effective and realistic energy-saving measures.

  8. Phenomenological model for particle production from the collisions of nucleons and pions with fissile elements at medium energies

    International Nuclear Information System (INIS)

    Alsmiller, F.S.; Alsmiller, R.G. Jr.; Gabriel, T.A.; Lillie, R.A.; Barish, J.

    1981-03-01

    A fission channel has been added to the intranuclear-cascade-evaporation model of nuclear reactions so that this model may be used to obtain the differential particle production data that are needed to study the transport of medium-energy nucleons and pions through fissionable material. The earlier work of Hahn and Bertini on the incorporation of fission-evaporation competition into the intranuclear-cascade-evaporation model has been retained, and the statistical model of fission has been utilized to predict particle production from the fission process. Approximate empirically derived kinetic energies and deformation energies are used in the statistical model. The calculated number of emitted neutrons and residual nuclei distributions are in reasonable agreement with experimental data, but the number of emitted neutrons at the higher incident nucleon energies (approx. > 500 MeV) are sensitive to the level density parameter used. 9 figures, 2 tables

  9. The effect of output-input isolation on the scaling and energy consumption of all-spin logic devices

    International Nuclear Information System (INIS)

    Hu, Jiaxi; Haratipour, Nazila; Koester, Steven J.

    2015-01-01

    All-spin logic (ASL) is a novel approach for digital logic applications wherein spin is used as the state variable instead of charge. One of the challenges in realizing a practical ASL system is the need to ensure non-reciprocity, meaning the information flows from input to output, not vice versa. One approach described previously, is to introduce an asymmetric ground contact, and while this approach was shown to be effective, it remains unclear as to the optimal approach for achieving non-reciprocity in ASL. In this study, we quantitatively analyze techniques to achieve non-reciprocity in ASL devices, and we specifically compare the effect of using asymmetric ground position and dipole-coupled output/input isolation. For this analysis, we simulate the switching dynamics of multiple-stage logic devices with FePt and FePd perpendicular magnetic anisotropy materials using a combination of a matrix-based spin circuit model coupled to the Landau–Lifshitz–Gilbert equation. The dipole field is included in this model and can act as both a desirable means of coupling magnets and a source of noise. The dynamic energy consumption has been calculated for these schemes, as a function of input/output magnet separation, and the results show that using a scheme that electrically isolates logic stages produces superior non-reciprocity, thus allowing both improved scaling and reduced energy consumption

  10. The effect of output-input isolation on the scaling and energy consumption of all-spin logic devices

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jiaxi; Haratipour, Nazila; Koester, Steven J., E-mail: skoester@umn.edu [Department of Electrical and Computer Engineering, University of Minnesota-Twin Cities, 200 Union St. SE, Minneapolis, Minnesota 55455 (United States)

    2015-05-07

    All-spin logic (ASL) is a novel approach for digital logic applications wherein spin is used as the state variable instead of charge. One of the challenges in realizing a practical ASL system is the need to ensure non-reciprocity, meaning the information flows from input to output, not vice versa. One approach described previously, is to introduce an asymmetric ground contact, and while this approach was shown to be effective, it remains unclear as to the optimal approach for achieving non-reciprocity in ASL. In this study, we quantitatively analyze techniques to achieve non-reciprocity in ASL devices, and we specifically compare the effect of using asymmetric ground position and dipole-coupled output/input isolation. For this analysis, we simulate the switching dynamics of multiple-stage logic devices with FePt and FePd perpendicular magnetic anisotropy materials using a combination of a matrix-based spin circuit model coupled to the Landau–Lifshitz–Gilbert equation. The dipole field is included in this model and can act as both a desirable means of coupling magnets and a source of noise. The dynamic energy consumption has been calculated for these schemes, as a function of input/output magnet separation, and the results show that using a scheme that electrically isolates logic stages produces superior non-reciprocity, thus allowing both improved scaling and reduced energy consumption.

  11. Spin-polarized high-energy scattering of charged leptons on nucleons

    Energy Technology Data Exchange (ETDEWEB)

    Burkardt, M. [New Mexico State Univ., Las Cruces, NM (United States). Dept. of Physics; Miller, C.A. [TRIUMF, Vancouver, BC (Canada); Nowak, W.D. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2009-08-15

    The proton is a composite object with spin one-half, understood to contain highly relativistic spin one-half quarks exchanging spin-one gluons, each possibly with significant orbital angular momenta. While their fundamental interactions are well described by Quantum ChromoDynamics (QCD), our standard theory of the strong interaction, nonperturbative calculations of the internal structure of the proton based directly on QCD are beginning to provide reliable results. Most of our present knowledge of the structure of the proton is based on experimental measurements interpreted within the rich framework of QCD. An area presently attracting intense interest, both experimental and theoretical, is the relationship between the spin of the proton and the spins and orbital angular momenta of its constituents. While remarkable progress has been made, especially in the last decade, the discovery and investigation of new concepts have revealed that much more remains to be learned. This progress is reviewed and an outlook for the future is offered. (orig.)

  12. Spin-polarized high-energy scattering of charged leptons on nucleons

    International Nuclear Information System (INIS)

    Burkardt, M.; Nowak, W.D.

    2009-08-01

    The proton is a composite object with spin one-half, understood to contain highly relativistic spin one-half quarks exchanging spin-one gluons, each possibly with significant orbital angular momenta. While their fundamental interactions are well described by Quantum ChromoDynamics (QCD), our standard theory of the strong interaction, nonperturbative calculations of the internal structure of the proton based directly on QCD are beginning to provide reliable results. Most of our present knowledge of the structure of the proton is based on experimental measurements interpreted within the rich framework of QCD. An area presently attracting intense interest, both experimental and theoretical, is the relationship between the spin of the proton and the spins and orbital angular momenta of its constituents. While remarkable progress has been made, especially in the last decade, the discovery and investigation of new concepts have revealed that much more remains to be learned. This progress is reviewed and an outlook for the future is offered. (orig.)

  13. Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

    OpenAIRE

    Razaque, Abdul; Elleithy, Khaled M.

    2014-01-01

    This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols,...

  14. Pion production - a probe for coherence in medium energy heavy ion collisions

    International Nuclear Information System (INIS)

    Stachel, J.

    1985-01-01

    Neutral pion production is observed in heavy ion collisions at beam energies as low as 25 MeV/u, where this process is consumming the major portion of the total center of mass energy available. At these low beam energies single nucleon nucleon collision models and also models that incorporate the cooperative sharing of the beam energy of several nucleons do not reproduce the data. Rather, the data presented here call for a fully coherent production mechanism. (orig.)

  15. High and medium high energy lines in France. The SATURNE case

    International Nuclear Information System (INIS)

    Milleret, G.

    1994-01-01

    Located in the Paris area, the SATURNE accelerator produces high energy charged particles: protons, deuterons, helium 3, helium 4, neutrons. The beams, with very flexible characteristics (linear energy transfer, flexible environment, dimension and intensity) for simulation of cosmic particles or high energy accelerator environments, allow for testing various individual or complete components. The various commercial offers and prices are presented. 5 fig., 2 ref

  16. Spin and chirality effects in antler-topology processes at high energy e{sup +}e{sup -} colliders

    Energy Technology Data Exchange (ETDEWEB)

    Choi, S. Y. [Department of Physics, Chonbuk National University, 561-756, Jeonbuk (Korea, Republic of); Department of Physics and Astronomy, Pittsburgh Particle physics, Astrophysics, and Cosmology Center, University of Pittsburgh, 15260, Pittsburgh, PA (United States); Christensen, N. D. [Department of Physics, Illinois State University, 61790, Normal, IL (United States); Salmon, D.; Wang, X., E-mail: xiw77@pitt.edu [Department of Physics and Astronomy, Pittsburgh Particle physics, Astrophysics, and Cosmology Center, University of Pittsburgh, 15260, Pittsburgh, PA (United States)

    2015-10-06

    We perform a model-independent investigation of spin and chirality correlation effects in the antler-topology processes e{sup +}e{sup -}→P{sup +}P{sup -}→(ℓ{sup +}D{sup 0})(ℓ{sup -}D{sup -bar0}) at high-energy e{sup +}e{sup -} colliders with polarized beams. Generally the production process e{sup +}e{sup -}→P{sup +}P{sup -} can occur not only through the s-channel exchange of vector bosons, V{sup 0}, including the neutral Standard Model (SM) gauge bosons, γ and Z, but also through the s- and t-channel exchanges of new neutral states, S{sup 0} and T{sup 0}, and the u-channel exchange of new doubly charged states, U{sup --}. The general set of (non-chiral) three-point couplings of the new particles and leptons allowed in a renormalizable quantum field theory is considered. The general spin and chirality analysis is based on the threshold behavior of the excitation curves for P{sup +}P{sup -} pair production in e{sup +}e{sup -} collisions with longitudinal- and transverse-polarized beams, the angular distributions in the production process and also the production-decay angular correlations. In the first step, we present the observables in the helicity formalism. Subsequently, we show how a set of observables can be designed for determining the spins and chiral structures of the new particles without any model assumptions. Finally, taking into account a typical set of approximately chiral invariant scenarios, we demonstrate how the spin and chirality effects can be probed experimentally at a high-energy e{sup +}e{sup -} collider.

  17. Spin physics in the high energy hadron productions. A systematic study of the spin asymmetries induced by pp, γp, ep and νp collisions

    International Nuclear Information System (INIS)

    Kubo, K.-I.; Suzuki, K.; Nakajima, N.

    2002-01-01

    The spin polarizations of hadrons inclusively produced by pp, γp and νp collisions are studied by the quark rearrangement model. The present model is a phenomenological one based on the relativistic spin equations of motion and using the quark distribution functions in hadrons and photon. A general success of the model is demonstrated. We find usefulness of the present formulation for studying the dynamics producing spin asymmetry distributions and the statics determining signs and magnitudes of the spin polarization by reflecting the characteristic quark structure in hadrons. (author)

  18. Spin at Lausanne

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    From 25 September to 1 October, some 150 spin enthusiasts gathered in Lausanne for the 1980 International Symposium on High Energy Physics with Polarized Beams and Polarized Targets. The programme was densely packed, covering physics interests with spin as well as the accelerator and target techniques which make spin physics possible

  19. Spin-Caloritronic Batteries

    DEFF Research Database (Denmark)

    Yu, Xiao-Qin; Zhu, Zhen-Gang; Su, Gang

    2017-01-01

    The thermoelectric performance of a topological energy converter is analyzed. The H-shaped device is based on a combination of transverse topological effects involving the spin: the inverse spin Hall effect and the spin Nernst effect. The device can convert a temperature drop in one arm into an e...

  20. Recent results in the development of a global medium-energy nucleon-nucleus optical-model potential

    International Nuclear Information System (INIS)

    Madland, D.G.

    1988-02-01

    Initial results are presented for the determination of a global medium-energy nucleon-nucleus phenomenological optical-model potential using a relativistic Schroedinger representation. The starting point for this work is the global phenomenological optical-model potential of Schwandt /ital et al./, which is based on measured elastic scattering cross sections and analyzing power for polarized protons ranging from 80 to 180 MeV. This potential is optimally modified to reproduce experimental proton reaction cross sections as a function of energy, while allowing only minimal deterioration in the fits to the elastic cross sections and analyzing powers. Further modifications in the absorptive potential were found necessary to extrapolate the modified potential to higher energies. The final potential is converted to a neutron-nucleus potential by use of standard Lane model assumptions and by accounting approximately for the Coulomb correction. Comparisons of measured and calculated proton reaction and neutron total cross sections are presented for 27 Al, 56 Fe, and 208 Pb. Medium-energy optical-model potentials for complex projectiles are briefly discussed in an appendix. 7 refs., 20 figs

  1. Medium-energy electrons and heavy ions in Jupiter's magnetosphere - Effects of lower hybrid wave-particle interactions

    Science.gov (United States)

    Barbosa, D. D.

    1986-01-01

    A theory of medium-energy (about keV) electrons and heavy ions in Jupiter's magnetosphere is presented. Lower hybrid waves are generated by the combined effects of a ring instability of neutral wind pickup ions and the modified two-stream instability associated with transport of cool Iogenic plasma. The quasi-linear energy diffusion coefficient for lower hybrid wave-particle interactions is evaluated, and several solutions to the diffusion equation are given. Calculations based on measured wave properties show that the noise substantially modifies the particle distribution functions. The effects are to accelerate superthermal ions and electrons to keV energies and to thermalize the pickup ions on time scales comparable to the particle residence time. The S(2+)/S(+) ratio at medium energies is a measure of the relative contribution from Iogenic thermal plasma and neutral wind ions, and this important quantity should be determined from future measurements. The theory also predicts a preferential acceleration of heavy ions with an accleration time that scales inversely with the root of the ion mass. Electrons accelerated by the process contribute to further reionization of the neutral wind by electron impact, thus providing a possible confirmation of Alfven's critical velocity effect in the Jovian magnetosphere.

  2. 10 CFR Appendix W to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Medium Base Compact Fluorescent Lamps

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Uniform Test Method for Measuring the Energy Consumption of Medium Base Compact Fluorescent Lamps W Appendix W to Subpart B of Part 430 Energy DEPARTMENT OF... the previous step. Round the final energy consumption value, as applicable, to the nearest decimal...

  3. Beacon-S TM: Non-uniform attenuation correction for SPECT imaging. The new medium-energy transmission device for AXIS and IRIX

    International Nuclear Information System (INIS)

    Daniel Gagnon, D.

    1999-01-01

    The paper presents new medium-energy transmission device for SPECT imaging. Beacon-S includes a 356-keV medium energy 133 Ba source with a 10.54-year half-life. Beacon-S provide high-resolution and high-contrast transmission scans. The higher energy of the gamma substantially improves the transmission contrast for larger patients by virtue of better penetration through the body

  4. Medium energy heavy ion accelerator 14 UD Pelletron- a BARC-TIFR facility: a 5 year progress report 1989-1994

    International Nuclear Information System (INIS)

    Chatterjee, A.; Tandon, P.N.

    1995-01-01

    The medium energy heavy ion accelerator (MEHIA) facility based on 14 UD Pelletron set up under the collaborative project of Bhabha Atomic Research Centre (BARC) and Tata Institute of Fundamental Research (TIFR) at the TIFR campus at Bombay has been serving as a joint BARC-TIFR facility for heavy-ion accelerator based research. As this accelerator has just completed five years of its successful operations, it has been thought to be an appropriate time to bring out a report of the research work carried out with the accelerator facility over these last five years. To put the research work in proper perspective, the present report is formatted to provide a short write-up highlighting the work carried out in each area of activity along with a list of the publications which have resulted from these investigations. Some theoretical work related to the experimental activities with the pelletron accelerator has also been included in the list of publications. The research work in the area of nuclear physics, which forms the main thrust of the research activities with the accelerator, covers areas of high spin states, high energy photons, resonances in heavy ion reactions, heavy ion elastic and transfer reactions, heavy ion fusion-fission reactions and radiochemical studies in heavy ion reactions. The interdisciplinary areas of research include condensed matter physics and accelerator based atomic physics. In addition to the above topics the present report also describes the work related to the pelletron accelerator and associated experimental facilities, gas detector development work, data acquisition systems and spectrometer for heavy recoil ions under development. The present status of the superconducting Linac booster project is also briefly described. (author). refs., tabs

  5. Energy-level repulsion by spin-orbit coupling in two-dimensional Rydberg excitons

    Science.gov (United States)

    Stephanovich, V. A.; Sherman, E. Ya.; Zinner, N. T.; Marchukov, O. V.

    2018-05-01

    We study the effects of Rashba spin-orbit coupling on two-dimensional Rydberg exciton systems. Using analytical and numerical arguments we demonstrate that this coupling considerably modifies the wave functions and leads to a level repulsion that results in a deviation from the Poissonian statistics of the adjacent level distance distribution. This signifies the crossover to nonintegrability of the system and hints at the possibility of quantum chaos emerging. Such behavior strongly differs from the classical realization, where spin-orbit coupling produces highly entangled, chaotic electron trajectories in an exciton. We also calculate the oscillator strengths and show that randomization appears in the transitions between states with different total momenta.

  6. Low energy excitations in fermionic spin glasses: A quantum-dynamical image of Parisi symmetry breaking

    International Nuclear Information System (INIS)

    Oppermann, R.; Rosenow, B.

    1997-10-01

    We report large effects of Parisi replica permutation symmetry breaking (RPSB) on elementary excitations of fermionic systems with frustrated magnetic interactions. The electronic density of states is obtained exactly in the zero temperature limit for (K = 1)- step RPSB together with relations for arbitrary breaking K, which lead to a new fermionic and dynamical Parisi solution at K = ∞. The Ward identity for charge conservation indicates RPSB-effects on the conductivity in metallic quantum spin glasses. This implies that RPSB is essential for any fermionic system showing spin glass sections within its phase diagram. An astonishing similarity with a neural network problem is also observed. (author)

  7. Spin-orbit excitation energies, anisotropic exchange, and magnetic phases of honeycomb RuCl3

    OpenAIRE

    Yadav, Ravi; Bogdanov, Nikolay A.; Katukuri, Vamshi M.; Nishimoto, Satoshi; Brink, Jeroen van den; Hozoi, Liviu

    2016-01-01

    Large anisotropic exchange in 5d and 4d oxides and halides open the door to new types of magnetic ground states and excitations, inconceivable a decade ago. A prominent case is the Kitaev spin liquid, host of remarkable properties such as protection of quantum information and the emergence of Majorana fermions. Here we discuss the promise for spin-liquid behavior in the 4d 5 honeycomb halide ?-RuCl3. From advanced electronic-structure calculations, we find that the Kitaev interaction is ferro...

  8. High spin exotic states and new method for pairing energy; Etats exotiques a hauts spins et nouvelle methode pour l`energie d`appariement nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Molique, H.

    1996-01-19

    We present a new method called `PSY-MB`, initially developed in the framework of abstract group theory for the solution of the problem of strongly interacting multi-fermionic systems with particular to systems in an external rotating field. The validity of the new method (PSY-MB) is tested on model Hamiltonians. A detailed comparison between the obtained solutions and the exact ones is performed. The new method is used in the study of realistic nuclear Hamiltonians based on the Woods-Saxon potential within the cranking approximation to study the influence of residual monopole pairing interactions in the rare-earth mass region. In parallel with this new technique we present original results obtained with the Woods-Saxon mean-field and the self-consistent Hartree-Fock approximation in order to investigate such exotic effects as octupole deformations and hexadecapole C{sub 4}-polarizing deformations in the framework of high-spin physics. By developing these three approaches in one single work we prepare the ground for the nuclear structure calculations of the new generation - where the residual two-body interactions are taken into account also in the weak pairing limit. (author). 2370refs.

  9. Electric and magnetic field modulated energy dispersion, conductivity and optical response in double quantum wire with spin-orbit interactions

    Science.gov (United States)

    Karaaslan, Y.; Gisi, B.; Sakiroglu, S.; Kasapoglu, E.; Sari, H.; Sokmen, I.

    2018-02-01

    We study the influence of electric field on the electronic energy band structure, zero-temperature ballistic conductivity and optical properties of double quantum wire. System described by double-well anharmonic confinement potential is exposed to a perpendicular magnetic field and Rashba and Dresselhaus spin-orbit interactions. Numerical results show up that the combined effects of internal and external agents cause the formation of crossing, anticrossing, camel-back/anomaly structures and the lateral, downward/upward shifts in the energy dispersion. The anomalies in the energy subbands give rise to the oscillation patterns in the ballistic conductance, and the energy shifts bring about the shift in the peak positions of optical absorption coefficients and refractive index changes.

  10. Spin modes

    International Nuclear Information System (INIS)

    Gaarde, C.

    1985-01-01

    An analysis of spectra of (p,n) reactions showed that they were very selective in exciting spin modes. Charge exchange reactions at intermediate energies give important new understanding of the M1-type of excitations and of the spin structure of continuum p spectra in general. In this paper, the author discusses three charge exchange reactions: (p,n); ( 3 H,t); and (d,2p) at several targets. Low-lying states and the Δ region are discussed separately. Finally, the charge exchange reaction with heavy ion beams is briefly discussed. (G.J.P./Auth.)

  11. ANKE, a new facility for medium energy hadron physics at COSY-Juelich

    International Nuclear Information System (INIS)

    Barsov, S.; Bechstedt, U.; Bothe, W.; Bongers, N.; Borchert, G.; Borgs, W.; Braeutigam, W.; Buescher, M.; Cassing, W.; Chernyshev, V.; Chiladze, B.; Dietrich, J.; Drochner, M.; Dymov, S.; Erven, W.; Esser, R.; Franzen, A.; Golubeva, Ye.; Gotta, D.; Grande, T.; Grzonka, D.; Hardt, A.; Hartmann, M.; Hejny, V.; Horn, L. van; Jarczyk, L.; Junghans, H.; Kacharava, A.; Kamys, B.; Khoukaz, A.; Kirchner, T.; Klehr, F.; Klein, W.; Koch, H.R.; Komarov, V.I.; Kondratyuk, L.; Koptev, V.; Kopyto, S.; Krause, R.; Kravtsov, P.; Kruglov, V.; Kulessa, P.; Kulikov, A.; Lang, N.; Langenhagen, N.; Lepges, A.; Ley, J.; Maier, R.; Martin, S.; Macharashvili, G.; Merzliakov, S.; Meyer, K.; Mikirtychiants, S.; Mueller, H.; Munhofen, P.; Mussgiller, A.; Nekipelov, M.; Nelyubin, V.; Nioradze, M.; Ohm, H.; Petrus, A.; Prasuhn, D.; Prietzschk, B.; Probst, H.J.; Pysz, K.; Rathmann, F.; Rimarzig, B.; Rudy, Z.; Santo, R.; Paetz Schieck, H.; Schleichert, R.; Schneider, A.; Schneider, Chr.; Schneider, H.; Schwarz, U.; Seyfarth, H.; Sibirtsev, A.; Sieling, U.; Sistemich, K.; Selikov, A.; Stechemesser, H.; Stein, H.J.; Strzalkowski, A.; Watzlawik, K.-H.; Wuestner, P.; Yashenko, S.; Zalikhanov, B.; Zhuravlev, N.; Zwoll, K.; Zychor, I.; Schult, O.W.B.; Stroeher, H.

    2001-01-01

    ANKE is a new experimental facility for the spectroscopy of products from proton-induced reactions on internal targets. It has recently been implemented in the accelerator ring of the cooler synchrotron COSY of the Forschungszentrum Juelich (FZ-Juelich), Germany. The device consists of three dipole magnets, various target installations and dedicated detection systems. It will enable a variety of hadron-physics experiments like meson production in elementary proton-nucleon processes and studies of medium modifications in proton-nucleus interactions

  12. Thermal mass impact on energy performance of a low, medium and heavy mass building in Belgrade

    Directory of Open Access Journals (Sweden)

    Anđelković Bojan V.

    2012-01-01

    Full Text Available Heavy mass materials used in building structures and architecture can significantly affect building energy performance and occupant comfort. The purpose of this study was to investigate if thermal mass can improve the internal environment of a building, resulting in lower energy requirements from the mechanical systems. The study was focused on passive building energy performance and compared annual space heating and cooling energy requirements for an office building in Belgrade with several different applications of thermal mass. A three-dimensional building model was generated to represent a typical office building. Building shape, orientation, glazing to wall ratio, envelope insulation thickness, and indoor design conditions were held constant while location and thickness of building mass (concrete was varied between cases in a series of energy simulations. The results were compared and discussed in terms of the building space heating and cooling energy and demand affected by thermal mass. The simulation results indicated that with addition of thermal mass to the building envelope and structure: 100% of all simulated cases experienced reduced annual space heating energy requirements, 67% of all simulated cases experienced reduced annual space cooling energy requirements, 83% of all simulated cases experienced reduced peak space heating demand and 50% of all simulated cases experienced reduced peak space cooling demand. The study demonstrated that there exists a potential for reducing space heating and cooling energy requirements with heavy mass construction in the analyzed climate region (Belgrade, Serbia.

  13. Energy Storage Characteristic Analysis of Voltage Sags Compensation for UPQC Based on MMC for Medium Voltage Distribution System

    Directory of Open Access Journals (Sweden)

    Yongchun Yang

    2018-04-01

    Full Text Available The modular multilevel converter (MMC, as a new type of voltage source converter, is increasingly used because it is a distributed storage system. There are many advantages of using the topological structure of the MMC on a unified power quality controller (UPQC, and voltage sag mitigation is an important use of the MMC energy storage system for the power quality compensation process. In this paper, based on the analysis of the topology of the MMC, the essence of energy conversion in a UPQC of voltage sag compensation is analyzed; then, the energy storage characteristics are calculated and analyzed to determine the performance index of voltage sag compensation; in addition, the simulation method is used to verify the voltage sag compensation characteristics of the UPQC; finally, an industrial prototype of the UPQC based on an MMC for 10 kV of medium voltage distribution network has been developed, and the basic functions of UPQC have been tested.

  14. Exploring drivers for energy efficiency within small- and medium-sized enterprises: First evidences from Italian manufacturing enterprises

    International Nuclear Information System (INIS)

    Cagno, Enrico; Trianni, Andrea

    2013-01-01

    Highlights: ► Allowances, public financing and external pressures as major external drivers. ► Ambitious decision-makers with great entrepreneurial mind as major internal drivers. ► Effect of firm’s size (even within SMEs) on drivers to industrial energy efficiency. ► Preliminary evidences of the effect of firm’s internal and external complexity. ► Preliminary evidences of the effect of firm’s innovation characteristics. - Abstract: Several studies have investigated the barriers to industrial energy efficiency, but few have focused on the most effective means (drivers) to promote the adoption of energy-efficient technologies and practices. In this respect, Small and Medium-sized Enterprises (SMEs) have been completely overlooked despite interesting consequences for their overall energy consumption and their concurrent low levels of adoption of energy-efficiency measures. Starting from insights garnered from the extant literature on the drivers of industrial energy efficiency, this paper presents an empirical investigation of 71 Italian manufacturing SMEs through a multiple case-study approach. The research highlights the importance of allowances or public financing for energy efficiency interventions, as well as the importance of external pressures such as increases in energy prices and the introduction or increasing of fees on both resources consumed and on emissions of pollutants. Moreover, enterprises look favourably upon energy-efficient technologies which are able to provide long-term benefits, evidence of their willingness to adopt seemingly radical solutions when these are able to improve their long-term competitiveness. Other drivers considered as strategic for increasing energy efficiency are the presence within the company of people with great ambition and entrepreneurial mind and the management sensitivity to the issue. This paper also provides a preliminary analysis of how factors such as firm size, sector, supply chain complexity, and

  15. Optimization as investment decision support in a Swedish medium-sized iron foundry - A move beyond traditional energy auditing

    International Nuclear Information System (INIS)

    Thollander, Patrik; Mardan, Nawzad; Karlsson, Magnus

    2009-01-01

    Due to increased globalisation, industries are facing greater competition that is pressing companies into decreasing their expenses in order to increase their profits. As regards Swedish industry, it has been faced with substantial increases in energy prices in recent years. Barriers to energy efficiency such as imperfect information inhibit investments in energy efficiency measures, energy audits being one means of reducing barriers and overcoming imperfect information. However, an evaluation of such energy audits in Sweden reveals that it is chiefly low-cost measures that are undertaken as a result of an audit. Moreover, these audits often tend to focus on support processes such as ventilation, lighting, air compressors etc., while measures impacting production processes are often not as extensively covered, which underlines the need for further support in addition to energy audits. Decision support is practised in a variety of different disciplines such as optimization and simulation and the aim of this paper is to explore whether investment decision support practices may be used successfully towards small and medium-sized manufacturers in Sweden when complex production-related investment decisions are taken. The optimization results from the different cases, involving a foundry's investment in a new melting unit, indicate that with no electricity price fluctuations over the day, the investment seems sound as it lowers the overall energy costs. However, with fluctuating electricity prices, there are no large differences in energy costs between the option of retaining the existing five melting furnaces at the foundry and investing in a twin furnace and removing the holding furnaces - which was the initial investment plan for the foundry in the study. It would not have been possible to achieve this outcome without the use of investment decision support such as MIND. One of the main conclusions in this paper is that investment decision support, when strategic

  16. Energy efficiency and sustainability assessment of about 500 small and medium-sized enterprises in Central Europe region

    International Nuclear Information System (INIS)

    Viesi, Diego; Pozzar, Francesca; Federici, Alessandro; Crema, Luigi; Mahbub, Md Shahriar

    2017-01-01

    Nowadays more than 20 million small and medium-sized enterprises (SMEs) are located in the European Union (EU): they are a key driver for economic growth, innovation, employment and social integration. The first step towards better industrial energy and environmental performance is the acknowledgement of the savings potential that can be realized by the company ownership and management board. Following this goal, the CEEM (Central Environmental and Energy Management) project provided to about 500 Central Europe SMEs of 5 countries (Austria, the Czech Republic, Hungary, Italy and Slovenia) a user friendly and free of charge web tool called 3EMT (Eco Energy Efficiency Management Tool). Through a questionnaire the 3EMT analyzes and sums up eco-energy patterns, helps to self-assess the company environmental performance, benchmarks a company with other Central Europe’s enterprises, delivers a customized Assessment Report, suggests further services and facilities. In this paper, the large 3EMT database is analyzed, and statistics focused on SMEs eco-energy performance and future & innovation perspectives are presented and discussed. Furthermore, key challenges and key intervention points were defined by local stakeholders (policy makers, Energy Service Companies, SMEs representatives, researchers), this paper summarizes the main policy outcomes. - Highlights: • Evaluation of Central Europe SME performance in energy efficiency and sustainability. • Extension of SME statistics at European and national level. • Identification of key challenges and key interventions for new industrial policies.

  17. Statistics of energy levels and zero temperature dynamics for deterministic spin models with glassy behaviour

    NARCIS (Netherlands)

    Degli Esposti, M.; Giardinà, C.; Graffi, S.; Isola, S.

    2001-01-01

    We consider the zero-temperature dynamics for the infinite-range, non translation invariant one-dimensional spin model introduced by Marinari, Parisi and Ritort to generate glassy behaviour out of a deterministic interaction. It is argued that there can be a large number of metastable (i.e.,

  18. A test of Wigner's spin-isospin symmetry from double binding energy differences

    International Nuclear Information System (INIS)

    Van Isacker, P.; Warner, D.D.; Brenner, D.S.

    1996-01-01

    The spin-isospin or SU(4) symmetry is investigated. It is shown that the N = Z enhancements of |δV np | are an unavoidable consequence of Wigner's SU(4) symmetry and that the degree of the enhancement provides a sensitive test of the quality of the symmetry itself. (K.A.)

  19. Measurements of energy behaviour of spin-dependent np—observables over 1.2-3.7 GeV energy region Dubna ``Delta-Sigma'' Experiment

    Science.gov (United States)

    Sharov, V. I.; Anischenko, N. G.; Antonenko, V. G.; Averichev, S. A.; Azhgirey, L. S.; Bartenev, V. D.; Bazhanov, N. A.; Belyaev, A. A.; Blinov, N. A.; Borisov, N. S.; Borzakov, S. B.; Borzunov, Yu. T.; Bushuev, Yu. P.; Chernenko, L. P.; Chernykh, E. V.; Chumakov, V. F.; Dolgh, S. A.; Fedorov, A. N.; Fimushkin, V. V.; Finger, M.; Finger, M.; Golovanov, L. B.; Gurevich, G. M.; Guriev, D. K.; Janata, A.; Kirillov, A. D.; Kolomiets, V. G.; Komogorov, E. V.; Kovalenko, A. D.; Kovalev, A. I.; Krasnov, V. A.; Krstonoshich, P.; Kuzmin, E. S.; Kuzmin, N. A.; Ladygin, V. P.; Lazarev, A. B.; Lehar, F.; de Lesquen, A.; Liburg, M. Yu.; Livanov, A. N.; Lukhanin, A. A.; Maniakov, P. K.; Matafonov, V. N.; Matyushevsky, E. A.; Moroz, V. D.; Morozov, A. A.; Neganov, A. B.; Nikolaevsky, G. P.; Nomofilov, A. A.; Panteleev, Tz.; Pillpenko, Yu. K.; Pisarev, I. L.; Plis, Yu. A.; Polunin, Yu. P.; Prokofiev, A. N.; Prytkov, V. Yu.; Rukoyatkin, P. A.; Schedrov, V. A.; Schevelev, O. N.; Shilov, S. N.; Shindin, R. A.; Slunecka, M.; Slunečková, V.; Starikov, A. Yu.; Stoletov, G. D.; Strunov, L. N.; Svetov, A. L.; Usov, Yu. A.; Vasiliev, T.; Volkov, V. I.; Vorobiev, E. I.; Yudin, I. P.; Zaitsev, I. V.; Zhdanov, A. A.; Zhmyrov, V. N.

    2005-01-01

    New accurate data on the neutron-proton spin-dependent total cross section difference Δ σ L( np) at the neutron beam kinetic energies 1.4, 1.7, 1.9 and 2.0 GeV are presented. A number of physical and methodical results on investigation of an elastic np→pn charge exchange process over a few GeV region are also presented. Measurements were carried out at the Synchrophasotron and Nuclotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research.

  20. Decentralized energy management strategy based on predictive controllers for a medium voltage direct current photovoltaic electric vehicle charging station

    International Nuclear Information System (INIS)

    Torreglosa, Juan P.; García-Triviño, Pablo; Fernández-Ramirez, Luis M.; Jurado, Francisco

    2016-01-01

    Highlights: • Electric vehicle charging station supplied by photovoltaic, batteries and grid connection is analyzed. • The bus voltage is the key parameter for controlling the system by decentralized approach. • Decentralized control approach facilities the enlargement of the system. • Photovoltaic and battery systems are controlled by model predictive controllers. • Response by model predictive controllers improves that by PI controllers. - Abstract: The use of distributed charging stations based on renewable energy sources for electric vehicles has increased in recent years. Combining photovoltaic solar energy and batteries as energy storage system, directly tied into a medium voltage direct current bus, and with the grid support, results to be an interesting option for improving the operation and efficiency of electric vehicle charging stations. In this paper, an electric vehicle charging station supplied by photovoltaic solar panels, batteries and with grid connection is analysed and evaluated. A decentralized energy management system is developed for regulating the energy flow among the photovoltaic system, the battery and the grid in order to achieve the efficient charging of electric vehicles. The medium voltage direct current bus voltage is the key parameter for controlling the system. The battery is controlled by a model predictive controller in order to keep the bus voltage at its reference value. Depending on the state-of-charge of the battery and the bus voltage, the photovoltaic system can work at maximum power point tracking mode or at bus voltage sustaining mode, or even the grid support can be needed. The results demonstrate the proper operation and energy management of the electric vehicle charging station under study.

  1. Public acceptance of fusion energy and scientific feasibility of a fusion reactor. Spin-off effects of fusion research and development

    International Nuclear Information System (INIS)

    Morino, Nobuyuki; Ogawa, Yuichi

    1998-01-01

    It is observed that new and sophisticated technologies developed through research and development in relation to magnetic confinement fusion have been transferred to other industrial and scientific fields with remarkable spin-off effects. Approximately 10 years ago, the Japan Atomic Industrial Forum (JAIF) has investigated technical transfer and spin-off effects of fusion technologies developed in Japan. The essence of the results of this investigation as well as high technologies developed in the last decade, some of which are in the early stage of technical spin-off, are described. It is additionally explained that independent technical development conducted by our country as well as by engineers themselves is important in achieving effective spin-off. An outline of scientific spin-off effects is also described, including utilization technologies of fusion reactions besides those for energy production purposes, the progress of scientific understanding in the course of fusion research, and scientific information transfer and communication with other fields. (author)

  2. Medium Access Control for Thermal Energy Harvesting in Advanced Metering Infrastructures

    DEFF Research Database (Denmark)

    Vithanage, Madava D.; Fafoutis, Xenofon; Andersen, Claus Bo

    2013-01-01

    In this paper we investigate the feasibility of powering wireless metering devices, namely heat cost allocators, by thermal energy harvested from radiators. The goal is to take a first step toward the realization of Energy-Harvesting Advanced Metering Infrastructures (EH-AMIs). While traditional...

  3. Hot nuclei and search for multifragmentation in medium-energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Doubre, H.

    1988-01-01

    Some recent determinations of the excitation energies and temperatures of composite systems formed in intermediate-energy heavy-ion collisions are described and the issue of a limiting temperature is discussed. Several examples of experimental investigations of an eventual occurrence of a multifragmentation process are also described

  4. Inter-satellite calibration of FengYun 3 medium energy electron fluxes with POES electron measurements

    Science.gov (United States)

    Zhang, Yang; Ni, Binbin; Xiang, Zheng; Zhang, Xianguo; Zhang, Xiaoxin; Gu, Xudong; Fu, Song; Cao, Xing; Zou, Zhengyang

    2018-05-01

    We perform an L-shell dependent inter-satellite calibration of FengYun 3 medium energy electron measurements with POES measurements based on rough orbital conjunctions within 5 min × 0.1 L × 0.5 MLT. By comparing electron flux data between the U.S. Polar Orbiting Environmental Satellites (POES) and Chinese sun-synchronous satellites including FY-3B and FY-3C for a whole year of 2014, we attempt to remove less reliable data and evaluate systematic uncertainties associated with the FY-3B and FY-3C datasets, expecting to quantify the inter-satellite calibration factors for the 150-350 keV energy channel at L = 2-7. Compared to the POES data, the FY-3B and FY-3C data generally exhibit a similar trend of electron flux variations but more or less underestimate them within a factor of 5 for the medium electron energy 150-350 keV channel. Good consistency in the flux conjunctions after the inter-calibration procedures gives us certain confidence to generalize our method to calibrate electron flux measurements from various satellite instruments.

  5. Medium energy measurements of N-N parameters. Final technical report, April 1, 1994--September 30, 1996

    International Nuclear Information System (INIS)

    Ambrose, D.; Betts, W.; Coffey, P.; Glass, G.; McDonough, J.; Riley, P.; Tang, J.L.

    1998-08-01

    This document is a final technical report describing the accomplishments of the medium/high energy nuclear physics research program at the University of Texas at Austin. The research program had four main thrusts, only one of which can be considered as measurements of N-N parameters: (1) finishing the data analyses associated with recent LAMPF and TRIUMPF N-N experiments, whose overall purpose has been the determination of the nucleon-nucleon amplitudes, both for isospin 0 and 1 at medium energies; (2) continuing work on BNL E871, a search for rare decay modes of the K L ; (3) work on the RHIC-STAR project, an experiment to create and study a quark gluon plasma and nuclear matter at high energy density; (4) beginning a new AGS experiment (E896) which will search for the lowest mass state of the predicted strange di-baryons, the Ho, and other exotic states of nuclear matter through nucleus-nucleus collisions

  6. Low-energy spin dynamics of orthoferrites AFeO3 (A  =  Y, La, Bi)

    Science.gov (United States)

    Park, Kisoo; Sim, Hasung; Leiner, Jonathan C.; Yoshida, Yoshiyuki; Jeong, Jaehong; Yano, Shin-ichiro; Gardner, Jason; Bourges, Philippe; Klicpera, Milan; Sechovský, Vladimír; Boehm, Martin; Park, Je-Geun

    2018-06-01

    YFeO3 and LaFeO3 are members of the rare-earth orthoferrites family with Pbnm space group. Using inelastic neutron scattering, the low-energy spin excitations have been measured around the magnetic Brillouin zone center. Splitting of magnon branches and finite magnon gaps (∼2 meV) are observed for both compounds, where the Dzyaloshinsky–Moriya interactions account for most of this gap with some additional contribution from single-ion anisotropy. We also make comparisons with multiferroic BiFeO3 (R3c space group), in which similar behavior was observed. By taking into account all relevant local Dzyaloshinsky–Moriya interactions, our analysis allows for the precise determination of all experimentally observed parameters in the spin-Hamiltonian. We find that different properties of the Pbnm and R3c space group lead to the stabilization of a spin cycloid structure in the latter case but not in the former, which explains the difference in the levels of complexity of magnon band structures for the respective compounds.

  7. Nuclear structure studies by the scattering of medium-energy electrons. Progress report, September 1, 1984-August 31, 1985

    International Nuclear Information System (INIS)

    Peterson, G.A.; Hicks, R.S.

    1985-09-01

    The University of Massachusetts Medium Energy Nuclear Physics Group reports the status of its experimental and theoretical programs. An overview of projects in elastic and quasi-elastic electron scattering which have been completed in the past year is given. Projects which have been designed and which will soon be started are described as well. Descriptions of the theoretical models for nucleon-nucleon interactions, nuclear structure, electromagnetic interactions, and weak interactions are given as well. Listings of the literature of the group are given

  8. Spin and chirality effects in antler-topology processes at high energy e{sup +}e{sup -} colliders

    Energy Technology Data Exchange (ETDEWEB)

    Choi, S.Y. [Chonbuk National University, Department of Physics, Jeonbuk (Korea, Republic of); University of Pittsburgh, Department of Physics and Astronomy, Pittsburgh Particle physics, Astrophysics, and Cosmology Center, Pittsburgh, PA (United States); Christensen, N.D. [Illinois State University, Department of Physics, Normal, IL (United States); Salmon, D.; Wang, X. [University of Pittsburgh, Department of Physics and Astronomy, Pittsburgh Particle physics, Astrophysics, and Cosmology Center, Pittsburgh, PA (United States)

    2015-10-15

    We perform a model-independent investigation of spin and chirality correlation effects in the antler-topology processes e{sup +}e{sup -} → P{sup +}P{sup -} → (l{sup +}D{sup 0})(l{sup +} anti D{sup 0}) at highenergy e{sup +}e{sup -} colliders with polarized beams. Generally the production process e{sup +}e{sup -} → P{sup +}P{sup -} can occur not only through the s-channel exchange of vector bosons, V{sup 0}, including the neutral Standard Model (SM) gauge bosons, γ and Z, but also through the s- and t-channel exchanges of new neutral states, S{sup 0} and T{sup 0}, and the u-channel exchange of new doubly charged states, U{sup --}. The general set of (nonchiral) three-point couplings of the new particles and leptons allowed in a renormalizable quantum field theory is considered. The general spin and chirality analysis is based on the threshold behavior of the excitation curves for P{sup +}P{sup -} pair production in e{sup +}e{sup -} collisions with longitudinal- and transverse-polarized beams, the angular distributions in the production process and also the production-decay angular correlations. In the first step, we present the observables in the helicity formalism. Subsequently, we show how a set of observables can be designed for determining the spins and chiral structures of the new particles without any model assumptions. Finally, taking into account a typical set of approximately chiral invariant scenarios, we demonstrate how the spin and chirality effects can be probed experimentally at a high-energy e{sup +}e{sup -} collider. (orig.)

  9. Modulational instability and nano-scale energy localization in ferromagnetic spin chain with higher order dispersive interactions

    International Nuclear Information System (INIS)

    Kavitha, L.; Mohamadou, A.; Parasuraman, E.; Gopi, D.; Akila, N.; Prabhu, A.

    2016-01-01

    The nonlinear localization phenomena in ferromagnetic spin lattices have attracted a steadily growing interest and their existence has been predicted in a wide range of physical settings. We investigate the onset of modulational instability of a plane wave in a discrete ferromagnetic spin chain with physically significant higher order dispersive octupole–dipole and dipole–dipole interactions. We derive the discrete nonlinear equation of motion with the aid of Holstein–Primakoff (H–P) transformation combined with Glauber's coherent state representation. We show that the discrete ferromagnetic spin dynamics is governed by an entirely new discrete NLS model with complex coefficients not reported so far. We report the study of modulational instability (MI) of the ferromagnetic chain with long range dispersive interactions both analytically in the frame work of linear stability analysis and numerically by means of molecular dynamics (MD) simulations. Our numerical simulations explore that the analytical predictions correctly describe the onset of instability. It is found that the presence of the various exchange and dispersive higher order interactions systematically favors the local gathering of excitations and thus supports the growth of high amplitude, long-lived discrete breather (DB) excitations. We analytically compute the strongly localized odd and even modes. Further, we employ the Jacobi elliptic function method to solve the nonlinear evolution equation and an exact propagating bubble-soliton solution is explored. - Highlights: • Higher order dispersive interactions plays significant role in ferromagnetic spin chain. • The energy localization is studied both analytically and numerically. • The existence of DBs are studied under the effect of higher order dispersive interaction.

  10. Excess energy and decoherence factor of a qubit coupled to a one-dimensional periodically driven spin chain

    Science.gov (United States)

    Nag, Tanay

    2016-06-01

    We take a central spin model (CSM), consisting of a one-dimensional environmental Ising spin chain and a single qubit connected globally to all the spins of the environment, to study the excess energy (EE) of the environment and the logarithm of decoherence factor namely, generalized fidelity susceptibility per site (GFSS), associated with the qubit under a periodic driving of the transverse field term of environment across its critical point using the Floquet theory. The coupling to the qubit, prepared in a pure state, with the transverse field of the spin chain yields two sets of EE corresponding to the two species of Floquet operators. In the limit of weak coupling, we derive an approximated expression of GFSS after an infinite number of driving period which can successfully estimate the low- and intermediate-frequency behavior of GFSS obtained numerically with a large number of time periods. Our main focus is to analytically investigate the effect of system-environment coupling strength on the EEs and GFSS and relate the behavior of GFSS to EEs as a function of frequency by plausible analytical arguments. We explicitly show that the low-frequency beatinglike pattern of GFSS is an outcome of two frequencies, causing the oscillations in the two branches of EEs, that are dependent on the coupling strength. In the intermediate frequency regime, dip structure observed in GFSS can be justified by the resonance peaks of EEs at those coupling parameter-dependent frequencies; high-frequency saturation behavior of EEs and GFSS are controlled by the same static Hamiltonian and the associated saturation values are related to the coupling strength.

  11. Study of nuclear isovector spin responses from polarization transfer in (p,n) reactions at intermediate energies

    International Nuclear Information System (INIS)

    Wakasa, Tomotsugu

    1997-01-01

    We have measured a complete set of polarization transfer observables has been measured for quasi-free (p vector, n vector) reactions on 2 H, 6 Li, 12 C, 40 Ca, and 208 Pb at a bombarding energy of 346MeV and a laboratory scattering angle of 22deg (q=1.7 fm -1 ). The polarization transfer observables for all five targets are remarkably similar. These polarization observables yield separated spin-longitudinal (σ·q) and spin-transverse (σxq) nuclear responses. These results are compared to the spin-transverse responses measured in deep-inelastic electron scattering as well as to nuclear responses based on the random phase approximation. Such a comparison reveals an enhancement in the (p vector, n vector) spin-transverse channel, which masks the effect of pionic correlations in the response ratio. Second, the double differential cross sections at θ lab between 0deg and 12.3deg and the polarization transfer D NN at 0deg for the 90 Zr(p,n) reaction are measured at a bombarding energy of 295MeV. The Gamow-Teller(GT) strength B(GT) in the continuum deduced from the L=0 cross section is compared both with the perturbative calculation by Bertsch and Hamamoto and with the second-order random phase approximation calculation by Drozdz et al. The sum of B(GT) values up to 50MeV excitation becomes S β- =28.0±1.6 after subtracting the contribution of the isovector spin-monopole strength. This S β- value of 28.0±1.6 corresponds to about (93±5)% of the minimum value of the sum-rule 3(N-Z)=30. Last, first measurements of D NN (0deg) for (p vector, n vector) reactions at 295MeV yield large negative values up to 50MeV excitation for the 6 Li, 11 B, 12 C, 13 C(p vector, n vector) reactions. DWIA calculations using the Franey and Love (FL) 270MeV interaction reproduce differential cross sections and D NN (0deg) values, while the FL 325MeV interaction yield D NN (0deg) values less negative than the experimental values. (J.P.N.)

  12. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

    Science.gov (United States)

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-09-18

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

  13. Low-energy modes and medium-range correlated motions in Pd79Ge21 alloy glass

    International Nuclear Information System (INIS)

    Shibata, Kaoru; Mizuseki, Hiroshi; Suzuki, Kenji

    1993-01-01

    It is well known that there are excess modes over the sound wave in low energy region below about 10 meV in glass materials, which do not exist in corresponding crystalline materials. We examined the low energy modes in a Pd 79 Ge 21 alloys glass by means of inelastic neutron scattering. Measurements were performed on the crystal analyzer type time-of-flight spectrometer LAM-40 with PG(002) and Ge(311) analyzer mirror, which is installed at KENS. The dynamic structure factor S(Q,ω) was obtained over the wide momentum range from 0.5 to 5.2A -1 . The measured S(Q,ω)'s have almost same momentum (Q) dependence at each energy (ℎω) in the energy range from 2.0 to 8.0 meV. In the energy region below 3 meV, we found a small shoulder peak at Q = 1.7A -1 in the momentum dependence of S(Q,ω). It corresponds to a prepeak in S(Q). Therefore it is concluded that the low energy modes in Pd 79 Ge 21 alloy glass is mainly contributed from medium-range correlated motions in the cluster consisting of a few chemical short-range structure units of Pd 6 Ge trigonal prism. (author)

  14. Spin-dependent energy distribution of B-hadrons from polarized top decays considering the azimuthal correlation rate

    Directory of Open Access Journals (Sweden)

    S.M. Moosavi Nejad

    2016-04-01

    Full Text Available Basically, the energy distribution of bottom-flavored hadrons produced through polarized top quark decays t(↑→W++b(→Xb, is governed by the unpolarized rate and the polar and the azimuthal correlation functions which are related to the density matrix elements of the decay t(↑→bW+. Here we present, for the first time, the analytical expressions for the O(αs radiative corrections to the differential azimuthal decay rates of the partonic process t(↑→b+W+ in two helicity systems, which are needed to study the azimuthal distribution of the energy spectrum of the hadrons produced in polarized top decays. These spin-momentum correlations between the top quark spin and its decay product momenta will allow the detailed studies of the top decay mechanism. Our predictions of the hadron energy distributions also enable us to deepen our knowledge of the hadronization process and to test the universality and scaling violations of the bottom-flavored meson fragmentation functions.

  15. The study of quasi-projectiles produced in Ni+Ni and Ni+Au collisions: excitation energy and spin

    International Nuclear Information System (INIS)

    Buta, A.

    2003-02-01

    During the collision between the projectile and the target nuclei in the intermediate energy regime (E < 100 MeV/nucleon) two excited nuclei are mainly observed in the exit channel, the quasi projectile (QP) and the quasi target. They disintegrate by particle emission. However, this binary picture is perturbed by the emission of particles and light fragments with velocities intermediate between the projectile velocity and the target one, all along the interaction (midrapidity component). This work aim to determine the excitation energy and the intrinsic angular momentum (or spin) of quasi-projectiles produced in the Ni+Ni and Ni+Au collisions at 52 and 90 MeV/nucleon. The excitation energy is deduced from the kinematical characteristics of particles emitted by the quasi-projectile. They have to be separated from midrapidity particles. Three different scenarios have been used for this purpose. The spin of the quasi-projectile has been extracted from the experimental data by mean of proton and alpha particles multiplicities emitted by the QP in the Ni+Au at 52 MeV/nucleon reaction. The results have been compared to the predictions of a theoretical model based on nucleon transfers. Their evolution is qualitatively reproduced as a function of the violence of the collision. (author)

  16. Energy relaxation between low lying tunnel split spin-states of the single molecule magnet Ni4

    Science.gov (United States)

    de Loubens, G.; Chaves-O'Flynn, G. D.; Kent, A. D.; Ramsey, C.; Del Barco, E.; Beedle, C.; Hendrickson, D. N.

    2007-03-01

    We have developed integrated magnetic sensors to study quantum tunneling of magnetization (QTM) in single molecule magnet (SMMs) single crystals. These sensors incorporate a microstrip resonator (30 GHz) and a micro-Hall effect magnetometer. They have been used to investigate the relaxation rates between the 2 lowest lying tunnel split spin-states of the SMM Ni4 (S=4). EPR spectroscopy at 30 GHz and 0.4 K and concurrent magnetization measurements of several Ni4 single crystals are presented. EPR enables measurement of the energy splitting between the 2 lowest lying superposition states as a function of the longitudinal and transverse fields. The energy relaxation rate is determined in two ways. First, in cw microwave experiments the change in spin-population together with the microwave absorption directly gives the relaxation time from energy conservation in steady-state. Second, direct time-resolved measurements of the magnetization with pulsed microwave radiation have been performed. The relaxation time is found to vary by several orders of magnitude in different crystals, from a few seconds down to smaller than 100 μs. We discuss this and the form of the relaxation found for different crystals and pulse conditions.

  17. Medium Duty ARRA Data Reporting and Analysis; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Kenneth; Duran, Adam; Ragatz, Adam; Prohaska, Robert; Walkowicz, Kevin

    2015-06-11

    Medium-duty (MD) electric vehicle (EV) data collection and analysis will help drive design, purchase, and research investments. Over 4 million miles and 160,000 driving days of EV driving data were collected under this project. Publicly available data help drive technology research, development, and deployment. Feeding the vocational database for future analysis will lead to a better understanding of usage and will result in better design optimization and technology implementation. The performance of a vehicle varies with drive cycle and cargo load - MD vehicles are 'multi-functional.' Environment and accessory loads affect vehicle range and in turn add cost by adding battery capacity. MD EV vehicles can function in vocations traditionally serviced by gasoline or diesel vehicles. Facility implications (i.e., demand charges) need to be understood as part of site-based analysis for EV implementation.

  18. A low energy muon spin rotation and point contact tunneling study of niobium films prepared for superconducting cavities

    Science.gov (United States)

    Junginger, Tobias; Calatroni, S.; Sublet, A.; Terenziani, G.; Prokscha, T.; Salman, Z.; Suter, A.; Proslier, T.; Zasadzinski, J.

    2017-12-01

    Point contact tunneling and low energy muon spin rotation are used to probe, on the same samples, the surface superconducting properties of micrometer thick niobium films deposited onto copper substrates using different sputtering techniques: diode, dc magnetron and HIPIMS. The combined results are compared to radio-frequency tests performances of RF cavities made with the same processes. Degraded surface superconducting properties are found to correlate to lower quality factors and stronger Q-slope. In addition, both techniques find evidence for surface paramagnetism on all samples and particularly on Nb films prepared by HIPIMS.

  19. Singularity-free electrodynamics for point charges and dipoles: a classical model for electron self-energy and spin

    International Nuclear Information System (INIS)

    Blinder, S M

    2003-01-01

    It is shown how point charges and point dipoles with finite self-energies can be accommodated in classical electrodynamics. The key idea is the introduction of constitutive relations for the electromagnetic vacuum, which actually mirrors the physical reality of vacuum polarization. Our results reduce to conventional electrodynamics for scales large compared to the classical electron radius r 0 ∼ 2.8 x 10 -15 m. A classical simulation for a structureless electron is proposed, with the appropriate values of mass, spin and magnetic moment

  20. Direct acceleration of ions to low and medium energies by a crossed-laser-beam configuration

    Directory of Open Access Journals (Sweden)

    Yousef I. Salamin

    2011-07-01

    Full Text Available Calculations show that 10 keV helium and carbon ions, injected midway between two identical 1 TW-power crossed laser beams of radial polarization, can be accelerated in vacuum to energies of utility in ion lithography. As examples, identical laser beams, crossed at 10° and focused to waist radii of 7.42  μm, accelerate He^{2+} and C^{6+} ions to average kinetic energies near 75 and 165 keV over distances averaging less than 7 and 6 mm, respectively. The spread in kinetic energy in both cases is less than 1% and the particle average angular deflection is less than 7 mrad. More energy-demanding industrial applications require higher-power laser beams for their direct ion laser acceleration.

  1. Compound nucleus effects in spin-spin cross sections

    International Nuclear Information System (INIS)

    Thompson, W.J.

    1976-01-01

    By comparison with recent data, it is shown that spin-spin cross sections for low-energy neutrons may be dominated by a simple compound-elastic level-density effect, independent of spin-spin terms in the nucleon-nucleus optical-model potential. (Auth.)

  2. The many facets of QCD at low and medium energies: the role of the nucleus

    International Nuclear Information System (INIS)

    Mathiot, J.F.

    1991-01-01

    In the perspective of a European collaboration for a continuous wave electron accelerator in the 15-30 GeV energy range, the first ideas and numerical simulations are presented on the most important and original aspects of this project. The role that the nucleus can play in unravelling the quark dynamics at low and intermediate energies is emphasized. (author) 11 refs., 5 figs

  3. Spin-polarized spin excitation spectroscopy

    International Nuclear Information System (INIS)

    Loth, Sebastian; Lutz, Christopher P; Heinrich, Andreas J

    2010-01-01

    We report on the spin dependence of elastic and inelastic electron tunneling through transition metal atoms. Mn, Fe and Cu atoms were deposited onto a monolayer of Cu 2 N on Cu(100) and individually addressed with the probe tip of a scanning tunneling microscope. Electrons tunneling between the tip and the substrate exchange energy and spin angular momentum with the surface-bound magnetic atoms. The conservation of energy during the tunneling process results in a distinct onset threshold voltage above which the tunneling electrons create spin excitations in the Mn and Fe atoms. Here we show that the additional conservation of spin angular momentum leads to different cross-sections for spin excitations depending on the relative alignment of the surface spin and the spin of the tunneling electron. For this purpose, we developed a technique for measuring the same local spin with a spin-polarized and a non-spin-polarized tip by exchanging the last apex atom of the probe tip between different transition metal atoms. We derive a quantitative model describing the observed excitation cross-sections on the basis of an exchange scattering process.

  4. Energy dispersion of the electrosubbands in parabolic confining quantum wires: interplay of Rashba, Dresselhaus, lateral spin-orbit interaction and the Zeeman effect

    International Nuclear Information System (INIS)

    Zhang Tongyi; Zhao Wei; Liu Xueming

    2009-01-01

    We have made a thorough theoretical investigation of the interplay of spin-orbit interactions (SOIs) resulting from Rashba, Dresselhaus and the lateral parabolic confining potential on the energy dispersion relation of the spin subbands in a parabolic quantum wire. The influence of an applied external magnetic field is also discussed. We show the interplay of different types of SOI, as well as the Zeeman effect, leads to rather complex and intriguing electrosubbands for different spin branches. The effect of different coupling strengths and different magnetic field strengths is also investigated.

  5. Spin polarization of 34Al fragments produced by nucleon pickup at intermediate energies

    International Nuclear Information System (INIS)

    Turzo, K.; Himpe, P.; Borremans, D.; Mallion, S.; Neyens, G.; Vermeulen, N.; Yordanov, D.; Balabanski, D.L.; Belier, G.; Daugas, J.M.; Georgiev, G.; Oliveira de Santos, F.; Matea, I.; Stodel, Ch.; Penionzhkevich, Yu. E.

    2006-01-01

    The polarization of 34 Al fragments, produced by single neutron pickup from a 9 Be target by a 36 S projectile at 77.5 MeV/nucleon, have been observed at GANIL via the detection of resonantly destroyed β-asymmetry. The reaction-induced polarization is deduced using a tentative spin/parity assignment for the 34 Al ground state. A positive polarization was measured near the peak of the 34 Al yield curve. A kinematical model based on the spectator-participant model for projectile fragmentation reactions has been extended in order to take into account the features of pickup reactions, i.e., the picked-up nucleon having an average momentum equal to the Fermi momentum and aligned along the incident beam direction. The trend-line in the observed spin-orientation is very well reproduced by this model

  6. An overview of spin physics

    International Nuclear Information System (INIS)

    Prescott, C.Y.

    1991-07-01

    Spin physics is playing an increasingly important role in high energy experiments and theory. This review looks at selected topics in high energy spin physics that were discussed at the 9th International Symposium on High Energy Spin Physics at Bonn in September 1990

  7. Exploiting the Medium Term Biomass Energy Potentials in Austria. A Comparison of Costs and Macroeconomic Impact

    International Nuclear Information System (INIS)

    Steininger, K.W.; Voraberger, H.

    2003-01-01

    The transition to an implicitly solar-based energy system can make use of various specific biomass energy systems. This paper provides economic and environmental indicators for evaluating alternative options. The paper proceeds in three empirical steps. First, an expert survey supplies the primary biomass potentials available for non-food use in Austria and their respective costs. Second, an inquiry into investment, operating and financing costs of 30 different biomass energy use systems allows a standardized comparison among them and their relationship to fossil reference technologies. Third, a computable general equilibrium model of the Austrian economy is employed to quantify the impacts of fostering the use of distinct biomass energy technologies. The results allow us to distinguish between those technologies that tend to lead to an increase in both GDP and employment (e.g., combined heat and power production from sewage sludge biogas), to an increase only in employment, while GDP tends to diminish (e.g., district heating based on agricultural pellets) or to a decline in both (e.g., co-firing based on wood-chips, bark or industrial pellets). Individual technologies could account for up to one third of Austria's Kyoto obligation, while combinations of technologies, triggered by a combined CO2 tax and biomass energy subsidy for example, could almost fully lead to Austrian Kyoto-compliance

  8. Focusing of light energy inside a scattering medium by controlling the time-gated multiple light scattering

    Science.gov (United States)

    Jeong, Seungwon; Lee, Ye-Ryoung; Choi, Wonjun; Kang, Sungsam; Hong, Jin Hee; Park, Jin-Sung; Lim, Yong-Sik; Park, Hong-Gyu; Choi, Wonshik

    2018-05-01

    The efficient delivery of light energy is a prerequisite for the non-invasive imaging and stimulating of target objects embedded deep within a scattering medium. However, the injected waves experience random diffusion by multiple light scattering, and only a small fraction reaches the target object. Here, we present a method to counteract wave diffusion and to focus multiple-scattered waves at the deeply embedded target. To realize this, we experimentally inject light into the reflection eigenchannels of a specific flight time to preferably enhance the intensity of those multiple-scattered waves that have interacted with the target object. For targets that are too deep to be visible by optical imaging, we demonstrate a more than tenfold enhancement in light energy delivery in comparison with ordinary wave diffusion cases. This work will lay a foundation to enhance the working depth of imaging, sensing and light stimulation.

  9. Free-air ionization chamber, FAC-IR-300, designed for medium energy X-ray dosimetry

    International Nuclear Information System (INIS)

    Mohammadi, S.M.; Tavakoli-Anbaran, H.; Zeinali, H.Z.

    2017-01-01

    The primary standard for X-ray photons is based on parallel-plate free-air ionization chamber (FAC). Therefore, the Atomic Energy Organization of Iran (AEOI) is tried to design and build the free-air ionization chamber, FAC-IR-300, for low and medium energy X-ray dosimetry. The main aim of the present work is to investigate specification of the FAC-IR-300 ionization chamber and design it. FAC-IR-300 dosimeter is composed of two parallel plates, a high voltage (HV) plate and a collector plate, along with a guard electrode that surrounds the collector plate. The guard plate and the collector were separated by an air gap. For obtaining uniformity in the electric field distribution, a group of guard strips was used around the ionization chamber. These characterizations involve determining the exact dimensions of the ionization chamber by using Monte Carlo simulation and introducing correction factors.

  10. The strategies of European energy operators. Which strategic and capitalistic evolutions for the sector on a medium term?

    International Nuclear Information System (INIS)

    2012-11-01

    This article presents the content of a market study which aimed at describing the current regulatory context of energy markets in Europe and the degree of openness to competition, at analysing all figures concerning electricity and natural gas in different countries (production, consumption, balance of trade), at analysing development strategies of electricity providers and gas operators and at assessing their strengths and weaknesses, at comparing financial performance of leader groups and at assessing their financial flexibility, and at anticipating the reconfiguration of the sector on a medium term. Fifteen energy companies or operators have been analysed: Centrica, CEZ, E.ON, EDF, EDP, Enel, ENI, Fortum, Gas Natural, GDF Suez, Iberdrola, RWE, SSE, Vattenfall, Verbund

  11. Exploring QCD dynamics in medium energy γA semiexclusive collisions

    Directory of Open Access Journals (Sweden)

    A.B. Larionov

    2016-09-01

    Full Text Available We demonstrate that studies of the semiexclusive large angle photon–nucleus reactions: γ+A→h1+h2+(A−1⁎ with tagged photon beams of energies 6÷10 GeV which can be performed in Hall D at Thomas Jefferson National Acceleration Facility (TJNAF would allow to probe several aspects of the QCD dynamics: establish the t-range in which transition from soft to hard dynamics occurs, compare the strength of the interaction of various mesons and baryons with nucleons at the energies of few GeV, as well as look for the color transparency effects.

  12. Low energy consumption method for separating gaseous mixtures and in particular for medium purity oxygen production

    Science.gov (United States)

    Jujasz, Albert J.; Burkhart, James A.; Greenberg, Ralph

    1988-01-01

    A method for the separation of gaseous mixtures such as air and for producing medium purity oxygen, comprising compressing the gaseous mixture in a first compressor to about 3.9-4.1 atmospheres pressure, passing said compressed gaseous mixture in heat exchange relationship with sub-ambient temperature gaseous nitrogen, dividing the cooled, pressurized gaseous mixture into first and second streams, introducing the first stream into the high pressure chamber of a double rectification column, separating the gaseous mixture in the rectification column into a liquid oxygen-enriched stream and a gaseous nitrogen stream and supplying the gaseous nitrogen stream for cooling the compressed gaseous mixture, removing the liquid oxygen-enriched stream from the low pressure chamber of the rectification column and pumping the liquid, oxygen-enriched steam to a predetermined pressure, cooling the second stream, condensing the cooled second stream and evaporating the oxygen-enriched stream in an evaporator-condenser, delivering the condensed second stream to the high pressure chamber of the rectification column, and heating the oxygen-enriched stream and blending the oxygen-enriched stream with a compressed blend-air stream to the desired oxygen concentration.

  13. A non-linear steady state characteristic performance curve for medium temperature solar energy collectors

    Science.gov (United States)

    Eames, P. C.; Norton, B.

    A numerical simulation model was employed to investigate the effects of ambient temperature and insolation on the efficiency of compound parabolic concentrating solar energy collectors. The limitations of presently-used collector performance characterization curves were investigated and a new approach proposed.

  14. Final states in electroproduction and photoproduction at low and medium energies

    International Nuclear Information System (INIS)

    Marshall, R.

    1977-01-01

    A review is given of electroproduction and photoproduction at photon energies extending from the resonance region up to about 10 GeV. Comparisons are made between the various experiments and the appropriate theories in an attempt to understand more about the different production mechanisms - s channel resonances, t and u channel exchanges and quark-parton effects. (orig.) [de

  15. Code package for calculation of damage effects of medium-energy protons in metal targets

    International Nuclear Information System (INIS)

    Coulter, C.A.

    1976-12-01

    A program package was developed to calculate radiation damage effects produced in a metal target by protons in the 100-MeV to 3.5-GeV energy range. A detailed description is given of the control cards and data cards required to use the code package

  16. Heavy-flavor production and medium properties in high-energy nuclear collisions --What next?

    NARCIS (Netherlands)

    Aarts, G.; Aichelin, J.; Allton, C.; Arnaldi, R.; Bass, S. A.; Bedda, C.; Brambilla, N.; Bratkovskaya, E.; Braun-Munzinger, P.; Bruno, G. E.; Dahms, T.; Das, S. K.; Dembinski, H.; Djordjevic, M.; Ferreiro, E. G.; Frawley, A.; Gossiaux, P. B.; Granier de Cassagnac, R.; Grelli, A.; He, Ming; Horowitz, W. A.; Innocenti, G. M.; Jo, M.; Kaczmarek, O.; Kuijer, P; Laine, M.; Lombardo, M. P.; Mischke, A.; Munhoz, M. G.; Nahrgang, M.; Nguyen, Mai; Oliveira da Silva, A. C.; Petreczky, P.; Rothkopf, A.; Schmelling, M.; Scomparin, E.; Song, Ting; Stachel, J.; Suaide, A. A P; Tolos, L.; Trzeciak, B.; Uras, A.; van Doremalen, L.; Vermunt, L.; Vigolo, S.; Xu, N.; Ye, Z.; Zanoli, H.J.C.; Zhuang, P.

    2017-01-01

    Open and hidden heavy-flavor physics in high-energy nuclear collisions are entering a new and exciting stage towards reaching a clearer understanding of the new experimental results with the possibility to link them directly to the advancement in lattice Quantum Chromo-Dynamics (QCD). Recent results

  17. Probability of spin flipping of proton with energy 6.9 MeV at inelastic scattering with sup(54,56)Fe nuclei

    International Nuclear Information System (INIS)

    Prokopenko, V.S.; Sklyarenko, V.; Chernievskij, V.K.; Shustov, A.V.

    1980-01-01

    Spin-orbital effects of inelastic scattering of protons by nuclei with mean atomic weight are investigated along with the mechanisms of the reaction course by measuring proton spin flip. The experiment consists in measuring proton-gamma coincidences in mutually perpendicular planes by the technique of quick-slow coincidences. The excitation function of the 56 Fe(P,P 1 ) reaction is measured in the 3.5-6.2 MeV energy range. Angular dependences of probability of proton spin flip (a level of 2 + , 0.847 MeV) are measured at energies of incident protons of 4.96; 5.58 and 5.88 MeV. Measurements of probabilities of proton spin flipping at inelastic scattering by sup(54,56)Fe nuclei are performed in the process of studying spin-orbital effects and mechanisms of the reaction course. A conclusion is made that the inelastic scattering process in the energy range under investigation is mainly realized by two equivalent mechanisms: direct interaction and formation of a compound nucleus. Angular dependences for 54 Fe and 56 Fe noticeably differ in the values of probability of spin flip in the angular range of 50-150 deg

  18. Nuclear de-excitation processes following medium energy heavy ion collisions

    International Nuclear Information System (INIS)

    Blann, M.

    1986-09-01

    As heavy ion reaction studies have progressed from beam energies below 10 MeV/nucleon to higher energies, many non-equilibrium reaction phenomena have been observed. Among these are nucleon emission with velocities in excess of the beam velocity, incomplete momentum transfer to evaporation residue and fission-like fragments, γ-rays with energies in excess of 100 MeV, and π 0 production when beam energies are below the threshold for production by the nucleon-nucleon collision mechanism. Additionally, prefission neutrons have been observed in excess of numbers expected from equilibrium models. A few of the approaches which have been applied to these phenomena are as follows: Intranuclear cascade: two body collisions are assumed to mediate the equilibration. The geometry and momentum space is followed semiclassically. The approach has many successes though it may suffer in a few applications is not following holes; TDHF considers one body processes only; in the energy regime of interest, two body processes are important so that this may not be a viable approach; Boltzmann-Uehling-Uhlenbeck or Vlasov-Uehling-Uhlenbeck (BUU/VUU) equations combine both one body and two body dynamics. The spatial and momentum evolution of the reactions are followed in a mean field. These should be the Cadillacs of the models. They are computationally tedious, and sometimes significant approximations are made in order to achieve computational tract ability; models of collective deceleration. A very simple model approach is discussed to interpret these phenomena, the Boltzmann master equation (BME). The hybrid model was the first to be applied to the question of heavy ion precompound decay, and the BME second. 26 refs., 5 figs., 2 tabs

  19. The Nuclear Spin Nanomagnet

    OpenAIRE

    Korenev, V. L.

    2007-01-01

    Linearly polarized light tuned slightly below the optical transition of the negatively charged exciton (trion) in a single quantum dot causes the spontaneous nuclear spin polarization (self-polarization) at a level close to 100%. The effective magnetic field of spin-polarized nuclei brings the optical transition energy into resonance with photon energy. The resonantly enhanced Overhauser effect sustains the stability of the nuclear self-polarization even in the absence of spin polarization of...

  20. Quasiparticle band gap of organic-inorganic hybrid perovskites: Crystal structure, spin-orbit coupling, and self-energy effects

    Science.gov (United States)

    Gao, Weiwei; Gao, Xiang; Abtew, Tesfaye A.; Sun, Yi-Yang; Zhang, Shengbai; Zhang, Peihong

    2016-02-01

    The quasiparticle band gap is one of the most important materials properties for photovoltaic applications. Often the band gap of a photovoltaic material is determined (and can be controlled) by various factors, complicating predictive materials optimization. An in-depth understanding of how these factors affect the size of the gap will provide valuable guidance for new materials discovery. Here we report a comprehensive investigation on the band gap formation mechanism in organic-inorganic hybrid perovskites by decoupling various contributing factors which ultimately determine their electronic structure and quasiparticle band gap. Major factors, namely, quasiparticle self-energy, spin-orbit coupling, and structural distortions due to the presence of organic molecules, and their influences on the quasiparticle band structure of organic-inorganic hybrid perovskites are illustrated. We find that although methylammonium cations do not contribute directly to the electronic states near band edges, they play an important role in defining the band gap by introducing structural distortions and controlling the overall lattice constants. The spin-orbit coupling effects drastically reduce the electron and hole effective masses in these systems, which is beneficial for high carrier mobilities and small exciton binding energies.

  1. Medium-spin levels and a 360 ns Isup(π)=19-/2 isomer in the N=80 nucleus 137La

    International Nuclear Information System (INIS)

    Kortelahti, M.; Pakkanen, A.; Piiparinen, M.; Komppa, T.; Komu, R.

    1981-03-01

    The level structure of 137 La has been studied using the 138 Ba(p,2n) reaction and methods of in-beam γ-ray and conversion-electron spectroscopy. The 137 La level scheme has been established with 21 new levels with spins up to (19/2) - . A 360 ns (19/2) - isomer at 1870 keV has been identified and a (πgsub(7/2)(νhsub(11/2)sup(-1)dsub(3/2)sup(-1)sub(7 - ))sub(19/2) - configuration is suggested for it. The level ordering of the πhsub(11/2)x2 + multiplet has been discussed on the basis of the triaxial rotor-plus-particle model which suggests a slightly oblate triaxial shape to the 137 La nucleus. (author)

  2. Preparation of the FXG gel dosemeter and studying its response for low and medium energy X-rays

    International Nuclear Information System (INIS)

    Bero, M.; Kharita, M. H.

    2008-02-01

    Gel dosimetry method was found to be capable of addressing complicated issues related to dose measurements particularly in modern sophisticated radiotherapy applications. Ferrous-sulphate Xylenol-orange and Gelatin (FXG) radiochromic gel dosemeter is one of the systems used for such applications. Some chemical dosemeters show different response for low and medium energies X-rays in comparison with high energy-photons. The energy and dose rate dependence of the FXG dose response was examined. In addition to the detector response other important dosimetric properties of the system were investigated for different X-ray beam qualities with tube voltages in the range 100 - 300 kv. An orthovoltage X-ray therapy unit was used to irradiate standard sized samples of FXG from different batches for radiation doses in the range 0 - 8 Gy. This work includes in the first stage the preparation of the radiochromic gel dosemeter (FXG) as well as its calibration in gamma radiation field. Furthermore, the stability and reproducibility of measurements were tested. The obtained results were found to be suitable as a basis to carry on the next stage of this study. The second phase was centred about the delivery of radiation doses from X-ray source that has increasing energy and evaluating the gel material properties as a dosemeter in this case, with concentration on finding the changes of the gel material response with the changes in the applied X-ray energy. Therefore establishing the response radiation energy dependence and comparing the measurement results with other results taken from other known dosimetry system such as ion chambers. Experiments shows that the FXG gel detector has a dynamic rage suitable for the dose delivered in radiotherapy treatment; its response as a function of the dose rate is also stable in the range of radiation energies applied.(Author)

  3. Feasibility of satisfying electrical energy needs with hybrid systems for a medium-size hotel on Kish Island, Iran

    International Nuclear Information System (INIS)

    Fazelpour, Farivar; Soltani, Nima; Rosen, Marc A.

    2014-01-01

    The utilization of renewable resources is growing, in part due to the environmental impacts caused by fossil fuels. The largest sources of renewable energy are wind and solar and many predict that these energy sources will be increasingly used for distributed generation. In this paper, the feasibility is examined of a grid-independent system applied for a medium-size hotel in Kish Island, Iran. Furthermore, economic optimization is included in the assessment by using the Homer software as the optimization tool. Renewable and non-renewable energy sources (fossil fuels) are considered, and the final adoption of both cases is primarily based on their associated cost and efficiency. Sensitivity analyses are performed to determine the impact on performance of several key parameters: wind speed, solar radiation and fuel costs. The target location in this study is a hotel that has 125 rooms with the total annual electrical energy consumption of 2,628,000 kWh, and a peak demand of about 620 kW. The results of a comprehensive feasibility data analysis along with its economic evaluation indicate that the wind-diesel hybrid system with battery storage is most efficient energy system for supplying the hotel's electrical energy demands. - Highlights: • The required energy for a hotel in Kish Island, Iran is determined. • HOMER software is used in the analyses for both technical and economic criteria. • Four feasible systems are classified and the most economic system is identified. • Annual greenhouse gas emissions are considered for all systems

  4. Secondary electron emission from Au by medium energy atomic and molecular ions

    CERN Document Server

    Itoh, A; Obata, F; Hamamoto, Y; Yogo, A

    2002-01-01

    Number distributions of secondary electrons emitted from a Au metal surface have been measured for atomic and molecular ions of H sup + , He sup + , C sup + , N sup + , O sup + , H sup + sub 2 , H sup + sub 3 , HeH sup + , CO sup + and O sup + sub 2 in the energy range 0.3-2.0 MeV. The emission statistics obtained are described fairly well by a Polya function. The Polya parameter b, determining the distribution shape, is found to decrease monotonously with increasing emission yield gamma, revealing a surprising relationship of b gamma approx 1 over the different projectile species and impact energies. This finding supports certainly the electron cascading model. Also we find a strong negative molecular effect for heavier molecular ions, showing a significant reduction of gamma compared to the estimated values using constituent atomic projectile data.

  5. Determination of Proper Peaking Time for Ultra Lege detector at Medium Energies

    International Nuclear Information System (INIS)

    Karabidak, S. M.

    2008-01-01

    Reducing count losses and pile-up pulse effects in quantitative and qualitative analysis is necessary for accuracy of analysis. Therefore, the optimum peaking time for particular detector systems is important. For this purpose, pure Se and Zn elements were excited by 59.5 keV γ-rays from a 50 mCi 241 A m annular radioactive source in this study. The characteristic x-rays emitted from pure Se and Zn elements were detected by using an ultra low energy Ge (Ultra-LEGe) detector connecting Tennelec TC 244 spectroscopy amplifier at different peaking time modes. Overall pulse widths were determined by HM 203-7 oscilloscope connecting amplifier. The proper peaking time for ultra low energy germanium detector (Ultra-LEGe) is determined about 4 μs

  6. Hydraulic and marine energies. Market evolution and perspectives on the medium term for the sector actors

    International Nuclear Information System (INIS)

    2015-01-01

    In its first part, this report proposes an analysis of the hydraulic and marine energy sector and of its perspectives through the identification of its main activity determining factors, a presentation of the activity evolution until 2015, and a discussion of the process of concession renewal, and of the development of small hydroelectric projects. The second part presents and comments the financial performance of enterprises belonging to the sector, and the third part an overview of highlights and of development focuses of operators (increase of production capacities, concession renewals, international development, and diversification in other renewable energies). The third part reports an analysis of the sector context: structural brakes and drivers, hydraulic world market, hydraulic French market. The three last parts propose an analysis of the sector economic structure and of actors, data sheet for operators, equipment manufacturers and engineering companies, and economic and financial indicators for 192 operators which allow a comparative overview of these actors

  7. Rho meson self-energy and dielectron emissivity in an isospin-asymmetric pion medium

    International Nuclear Information System (INIS)

    Gulamov, T.I.; Titov, A.I.; Forschungszentrum Rossendorf e.V.; Kaempfer, B.; Technische Univ., Dresden

    1995-06-01

    The ρ meson self-energy in an isospin asymmetric pion gas at finite temperature and charged-pion chemical potential is evaluated. We utilize a conventional effective π-ρ Lagrangian and the functional integral representation of the partition function in the second order in the ρππ coupling constant. We analyze the gauge invariant rho meson polarization operator and its dependence on the invariant mass M and spatial momentum vertical stroke pvertical stroke of the ρ meson. The pole positions and the values of the imaginary parts of the self-energy for different polarization states have different functional dependences on M and vertical stroke pvertical stroke . The corresponding dielectron rate (calculated from the imaginary part of the polarization operators) shows a distinctive asymmetry when the momentum t=p + -p - is perpendicular or parallel to p, where p ± are the momenta of the electron pair. (orig.)

  8. Pre-equilibrium emission of nucleons from reactions induced by medium-energy heavy ions

    International Nuclear Information System (INIS)

    Korolija, M.; Holuh, E.; Cindro, N.; Hilscher, D.

    1984-01-01

    Recent data on fast-nucleon emission in heavy-ion-induced reactions are analysed successfully in terms of pre-equilibrium models; it is shown that the relevant parameters of those models preserve the physical meaning they have in light-ion-induced reactions. The initial exciton number obtained from a Griffin-plot analysis and the initial number of degrees of freedom, which is the relevant parameter of the modified HMB model, appear to be approximately equal for a given reaction at a given energy. It is inferred that, for heavy-ion reactions, the determination of such a parameter is substantially dominated by the centre-of-mass energy per nucleon above the Coulomb barrier, in contrast with the results of nucleon-induced reactions

  9. Improved Reaction and Activation Energies of [4+2] Cycloadditions, [3+3] Sigmatropic Rearrangements and Electrocyclizations with the Spin-Component-Scaled MP2 Method

    NARCIS (Netherlands)

    Goumans, T.P.M.; Ehlers, A.W.; Lammertsma, K.; Wuerthwein, E.-U.; Grimme, S.

    2004-01-01

    A new quantum mechanical scheme to calculate electronic correlation energies, spin-component-scaled MP2, was tested as a tool to predict reaction energies and barriers in computational organic chemistry. Three common pericyclic reactions with known unsatisfactory MP2 descriptions were reinvestigated

  10. Power Output Stability Research for Harvesting Automobile Exhaust Energy with Heat Capacity Material as Intermediate Medium

    Science.gov (United States)

    Xiao, Longjie; He, Tianming; Mei, Binyu; Wang, Yiping; Wang, Zongsong; Tan, Gangfeng

    2018-06-01

    Automobile exhaust energy thermoelectric utilization can promote energy-saving and emission-reduction. Unexpected urban traffic conditions lead to the hot-end temperature instability of the exhaust pipe-mounted thermoelectric generator (TEG), and influence the TEG power generation efficiency. The heat conduction oil circulation located at the hot-end could smooth the temperature fluctuation, at the expense of larger system size and additional energy supply. This research improves the TEG hot-end temperature stability by installing solid heat capacity material (SHCM) to the area between the outer wall of the exhaust pipe and the TEG, which has the merits of simple structure, light weight and no additional energy consumption. The exhaust temperature and flow rate characteristics with various driving conditions are firstly studied for the target engine. Then the convective heat transfer models of SHCM's hot-end and thermoelectric material's cold-end are established. Meanwhile, SHCM thermal properties' effects on the amplitude and response speed of the TEG hot-end temperature are studied. The candidate SHCM with the characteristics of low thermal resistance and high heat capacity is determined. And the heat transfer model going through from TEG's hot-end to the cold-end is established. The results show that the SHCM significantly improves the TEG hot-end temperature stability but slightly reduces the average power output. When the engine working conditions change a lot, the SHCM's improvement on the TEG hot-end temperature stability is more significant, but the reduction of the average power output becomes more remarkable.

  11. Energy from Biomass: technology assessment of small-medium scale biomass conversion systems

    OpenAIRE

    Cutz Ijchajchal, Luis Leonardo

    2016-01-01

    Mención Internacional en el título de doctor Bioenergy is a key resource to addressing challenges such as climate change (anthropogenic CO₂ emissions), pollution (suspended particles), energy security and human well-being. Currently, most of the biomass produced worldwide is consumed for cooking and space heating which has raised concerns among governments and policy-makers, especially due to threats to human health. The present thesis focuses on studying the technical and economic feasibi...

  12. Medium and Short Wave RF Energy Harvester for Powering Wireless Sensor Networks.

    Science.gov (United States)

    Leon-Gil, Jesus A; Cortes-Loredo, Agustin; Fabian-Mijangos, Angel; Martinez-Flores, Javier J; Tovar-Padilla, Marco; Cardona-Castro, M Antonia; Morales-Sánchez, Alfredo; Alvarez-Quintana, Jaime

    2018-03-03

    Internet of Things (IoT) is an emerging platform in which every day physical objects provided with unique identifiers are connected to the Internet without requiring human interaction. The possibilities of such a connected world enables new forms of automation to make our lives easier and safer. Evidently, in order to keep billions of these communicating devices powered long-term, a self-sustainable operation is a key point for realization of such a complex network. In this sense, energy-harvesting technologies combined with low power consumption ICs eliminate the need for batteries, removing an obstacle to the success of the IoT. In this work, a Radio Frequency (RF) energy harvester tuned at AM broadcast has been developed for low consumption power devices. The AM signals from ambient are detected via a high-performance antenna-free LC circuit with an efficiency of 3.2%. To maximize energy scavenging, the RF-DC conversion stage is based on a full-wave Cockcroft-Walton voltage multiplier (CWVM) with efficiency up to 90%. System performance is evaluated by rating the maximum power delivered into the load via its output impedance, which is around 62 μW, although power level seems to be low, it is able to power up low consumption devices such as Leds, portable calculators and weather monitoring stations.

  13. Soft mode and energy gap in spin wave spectrum for a second order orientation phase transition. AFMR in YFe3

    International Nuclear Information System (INIS)

    Balbashov, A.M.; Berezin, A.G.; Gufan, Yu.M.; Kolyadko, G.S.; Marchukov, P.Yu.; Rudashevskij, E.G.

    1987-01-01

    A pronounced energy gap of a nonmagnetoelastic origin is observed experimentally in the spectrum of the low-frequency (quasiferromagnetic) antiferromagnetic resonance branch during a second order spin-flip phase transition in an external magnetic field directed along the a axis of the rhombic weak ferromagnetic YFeO 3 . From the theory developed which takes into account the susceptibility along the antiferromagnetism axis and dissipation processes, it follows that beside the usual AFMR oscillatory branches there should also be a relaxation mode which is ''soft'' fo the given transition. The magnitude of the energy gaps, the values of the kinetic coefficients, Dzyaloshinsky field strengths and ratio of the longitudinal susceptibility to the transverse susceptibility are determined by analyzing the experimental data obtained in fields up to 130 kOe in the frequency range from 60 to 400 GHz at room temperature

  14. A signature for isoscalar-spin transitions in (d vector, d' vector) scattering at intermediate energy

    International Nuclear Information System (INIS)

    Morlet, M.; Bimbot, L.; Guillot, J.; Johnson, B.N.; Jourdan, F.; Langevin-Joliot, H.; Marty, N.; Rosier, L.; Wiele, J. van de; Willis, A.; Beatty, D.; Edwards, G.; Fergerson, R.W.; Glashausser, C.; Green, A.; Djalali, C.; Johnson, B.N.; Tomasi-Gustafsson, E.; Youn, M.Y.

    1991-05-01

    Three different signatures for isoscalar spin transitions in nuclei have been tested in the 12 C(d,d') 12 C reaction at 400 MeV. These signatures have values close to zero for the natural parity states, and range from 0.22 to 0.50 for the ΔS=1 ΔT=0, 12.7 MeV state. Preliminary results on 40 Ca(d,d') at 400 MeV are also presented. (author) 26 refs., 4 figs., 1 tab

  15. A high-spin isomer at high excitation energy in the neutron deficient nucleus $^{152}$Dy

    CERN Document Server

    Jansen, J F W; Chmielewska, D; De Meijer, R J

    1976-01-01

    A T/sub 1/2/=60+or-5 ns isomer at E/sub x/ approximately=5 MeV is found in the /sup 154/Gd( alpha ,6n)/sup 152/Dy reaction. The possible spin values are 15

  16. Analysis of hybrid waste-to-energy for medium-sized cities

    International Nuclear Information System (INIS)

    Balcazar, Juan Galvarino Cerda; Dias, Rubens Alves; Balestieri, José Antonio Perrella

    2013-01-01

    Urban centers have a huge demand for electricity and the growing problem of the solid waste management generated by their population, a relevant social and administrative problem. The correct disposal of the municipal solid waste (MSW) generated in cities is one of the most complex engineering problems that involves logistics, safety, environmental and energetic aspects for its adequate management. Due to a national policy of solid wastes recently promulgated, Brazilian cities are evaluating the technical and economic feasibility of incinerating the non-recyclable waste. São José dos Campos, a São Paulo State industrialized city, is considering the composting of organic waste for biogas production and mass incineration of non-recyclable waste. This paper presents a waste-to-energy system based on the integration of gas turbines to a MSW incinerator for producing thermal and electric energy as an alternative solution for the solid waste disposal in São José dos Campos, SP. A technical and economic feasibility study for the hybrid combined cycle plant is presented and revealed to be attractive when carbon credit and waste tax are included in the project income. - Highlights: ► We model a hybrid waste-to-energy cogeneration system for the disposal of MSW. ► Reference model for MSW treatment consists of biogas burning and composting. ► Hybrid cogeneration solution is superior to the biogas burning reference model. ► Carbon credit and waste tax increase the attractiveness of the proposed solution

  17. Energy efficient medium access protocol for wireless medical body area sensor networks.

    Science.gov (United States)

    Omeni, O; Wong, A; Burdett, A J; Toumazou, C

    2008-12-01

    This paper presents a novel energy-efficient MAC Protocol designed specifically for wireless body area sensor networks (WBASN) focused towards pervasive healthcare applications. Wireless body area networks consist of wireless sensor nodes attached to the human body to monitor vital signs such as body temperature, activity or heart-rate. The network adopts a master-slave architecture, where the body-worn slave node periodically sends sensor readings to a central master node. Unlike traditional peer-to-peer wireless sensor networks, the nodes in this biomedical WBASN are not deployed in an ad hoc fashion. Joining a network is centrally managed and all communications are single-hop. To reduce energy consumption, all the sensor nodes are in standby or sleep mode until the centrally assigned time slot. Once a node has joined a network, there is no possibility of collision within a cluster as all communication is initiated by the central node and is addressed uniquely to a slave node. To avoid collisions with nearby transmitters, a clear channel assessment algorithm based on standard listen-before-transmit (LBT) is used. To handle time slot overlaps, the novel concept of a wakeup fallback time is introduced. Using single-hop communication and centrally controlled sleep/wakeup times leads to significant energy reductions for this application compared to more ldquoflexiblerdquo network MAC protocols such as 802.11 or Zigbee. As duty cycle is reduced, the overall power consumption approaches the standby power. The protocol is implemented in hardware as part of the Sensiumtrade system-on-chip WBASN ASIC, in a 0.13- mum CMOS process.

  18. Theoretical study on pp → pnπ+ reaction at medium energies

    International Nuclear Information System (INIS)

    Ouyang, Zhen; Xie, Jujun; Zou, Bingsong; Xu, Hushan

    2009-01-01

    The pp → pnπ + reaction is a channel with the largest total cross section for pp collision in COSY/CSR energy region. In this work, we investigate individual contributions from various N* and Δ* resonances with mass up to about 2 GeV for the pp → pnπ + reaction. We extend a resonance model, which can reproduce the observed total cross section quite well, to give theoretical predictions of various differential cross sections for the present reaction at T p = 2.88 GeV. It could serve as a reference for identifying new physics in the future experiments at HIRFL-CSR. (author)

  19. Composition of medium energy cosmic rays from silicon to nickel measured with nuclear emulsion

    International Nuclear Information System (INIS)

    Behrnetz, S.; Kristiansson, K.; Lindstam, S.; Soederstroem, K.

    1975-12-01

    The cosmic ray charge spectrum has been studied in three nuclear emulsion stacks exposed in balloon flights from Fort Churchill, Canada, in 1967 and 1970. The charge region is 14 <= Z < E 28 and the energy interval is about 400-800 MeV/Nucleon. The particles are identified by measurements with a nuclear track photometer which is described in some detail. The charge spectrum is extrapolated to the top of the atmosphere and comparisons with other measurements are made. Special emphasis is put on the abundance ratios (Sc-Mn)/Fe, (Sc+Ti)/(V+Cr) and Ni/Fe. (Auth.)

  20. Feasibility study and energy efficiency estimation of geothermal power station based on medium enthalpy water

    Directory of Open Access Journals (Sweden)

    Borsukiewicz-Gozdur Aleksandra

    2007-01-01

    Full Text Available In the work presented are the results of investigations regarding the effectiveness of operation of power plant fed by geothermal water with the flow rate of 100, 150, and 200 m3/h and temperatures of 70, 80, and 90 °C, i. e. geothermal water with the parameters available in some towns of West Pomeranian region as well as in Stargard Szczecinski (86.4 °C, Poland. The results of calculations regard the system of geothermal power plant with possibility of utilization of heat for technological purposes. Analyzed are possibilities of application of different working fluids with respect to the most efficient utilization of geothermal energy. .

  1. Simulating the formation and evolution of galaxies: multi-phase description of the interstellar medium, star formation, and energy feedback

    Science.gov (United States)

    Merlin, E.; Chiosi, C.

    2007-10-01

    Context: Modelling the gaseous component of the interstellar medium (ISM) by Smoothed Particles Hydrodynamics in N-Body simulations (NB-TSPH) is still very crude when compared to the complex real situation. In the real ISM, many different and almost physically decoupled components (phases) coexist for long periods of time, and since they spread over wide ranges of density and temperature, they cannot be correctly represented by a unique continuous fluid. This would influence star formation which is thought to take place in clumps of cold, dense, molecular clouds, embedded in a warmer, neutral medium, that are almost freely moving throughout the tenuous hot ISM. Therefore, assuming that star formation is simply related to the gas content without specifying the component in which this is both observed and expected to occur may not be physically sound. Aims: We consider a multi-phase representation of the ISM in NB-TSPH simulations of galaxy formation and evolution with particular attention to the case of early-type galaxies. Methods: Cold gas clouds are described by the so-called sticky particles algorithm. They can freely move throughout the hot ISM medium; stars form within these clouds and the mass exchange among the three baryonic phases (hot gas, cold clouds, stars) is governed by radiative and Compton cooling and energy feedback by supernova (SN) explosions, stellar winds, and UV radiation. We also consider thermal conduction, cloud-cloud collisions, and chemical enrichment. Results: Our model agrees with and improves upon previous studies on the same subject. The results for the star formation rate agree with recent observational data on early-type galaxies. Conclusions: These models lend further support to the revised monolithic scheme of galaxy formation, which has recently been strengthened by high redshift data leading to the so-called downsizing and top-down scenarios.

  2. Peculiarities of light ion-nucleus scattering in medium-energy region

    International Nuclear Information System (INIS)

    Berezhnoj, Yu.A.; Pilipenko, V.V.

    1982-01-01

    Differential cross-sections of 3 He and 4 He nuclei elastic scattering at E > or approximately 10 MeV/nucleon are analyzed in the quasi-classical approximation. At energies E > or approximately 25 MeV/nucleon in differential cross sections of 3 He and 4 He nuclei elastic scattering by atomic nuclei in the field of scattering angles THETA > or approximately 35 deg diffraction minima start to appear. ScuiSuch effect of Fraunhofer cross section oscillations is eluciiated on the basis of diffraction theory by means of modelfree determination of nuclear scattering phase and quantum deviation function. It is shown that the elastic scattering cross section in the field of energies under consideration represents a typical quasiclassical picture of ''iridescent'' scattering at strong absorption. The theoretical analysis performed permits to correctly describe the experimentally measured differential cross sections of 3 He nuclei elastic scattering at 109.2 MeV by 40 Ca, 58 Ni nuclei and at 118.5 NeV by 58 Ni nuclei as well as 4 He at 166 MeV by 24 Mg, 32 S and at 141.7 MeV by 40 Ca nuclei

  3. Electrification pathways for Kenya-linking spatial electrification analysis and medium to long term energy planning

    Science.gov (United States)

    Moksnes, Nandi; Korkovelos, Alexandros; Mentis, Dimitrios; Howells, Mark

    2017-09-01

    In September 2015 UN announced 17 Sustainable Development goals (SDG) from which goal number 7 envisions universal access to modern energy services for all by 2030. In Kenya only about 46% of the population currently has access to electricity. This paper analyses hypothetical scenarios, and selected implications, investigating pathways that would allow the country to reach its electrification targets by 2030. Two modelling tools were used for the purposes of this study, namely OnSSET and OSeMOSYS. The tools were soft-linked in order to capture both the spatial and temporal dynamics of their nature. Two electricity demand scenarios were developed representing low and high end user consumption goals respectively. Indicatively, results show that geothermal, coal, hydro and natural gas would consist the optimal energy mix for the centralized national grid. However, in the case of the low demand scenario a high penetration of stand-alone systems is evident in the country, reaching out to approximately 47% of the electrified population. Increasing end user consumption leads to a shift in the optimal technology mix, with higher penetration of mini-grid technologies and grid extension.

  4. Techno-economic analysis of an autonomous power system integrating hydrogen technology as energy storage medium

    Energy Technology Data Exchange (ETDEWEB)

    Tzamalis, G. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece); Zoulias, E.I.; Stamatakis, E.; Varkaraki, E. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Lois, E.; Zannikos, F. [Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece)

    2011-01-15

    Two different options for the autonomous power supply of rural or/and remote buildings are examined in this study. The first one involves a PV - diesel based power system, while the second one integrates RES and hydrogen technologies for the development of a self - sustained power system. The main objective is the replacement of the diesel generator and a comparison between these two options for autonomous power supply. Model simulations of the two power systems before and after the replacement, an optimization of the component sizes and a techno - economic analysis have been performed for the purpose of this study. A sensitivity analysis taking into account future cost scenarios for hydrogen technologies is also presented. The results clearly show that the Cost of Energy Produced (COE) from the PV - hydrogen technologies power system is extremely higher than the PV - diesel power system. However, the adopted PV - hydrogen technologies power system reduces to zero the Green - House Gas (GHG) emissions. Moreover, the sensitivity analysis indicates that COE for the latter system can be further reduced by approximately 50% compared to its initial value. This could be achieved by reducing critical COE's parameters, such as PEM electrolyser and fuel cell capital costs. Hence, a possible reduction on the capital costs of hydrogen energy equipment in combination with emissions reduction mentioned above could make hydrogen - based power systems more competitive. (author)

  5. Characterisation of urinary stones in the presence of iodinated contrast medium using dual-energy CT: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jia; Qu, Mingliang; Duan, Xinhui; Takahashi, Naoki; Kawashima, Akira; Leng, Shuai; McCollough, Cynthia H. [Mayo Clinic, Department of Radiology, Rochester, MN (United States)

    2012-12-15

    To develop a dual-energy CT (DECT) method for differentiating uric acid (UA) from non-UA stones in the presence of iodinated contrast medium. Thirty UA and 45 non-UA stones were selected after infra-red spectroscopic analysis and independently placed in a 1.5-ml vial, which was filled first with saline and then with increasing concentrations of iodine. For each condition, tubes were put in a 35-cm water phantom and examined using a dual-source CT system at 100 and 140 kV. Virtual unenhanced images created from CT data sets of the stones in iodine-containing solutions provided position and volume information. This map was used to calculate a CT number ratio to differentiate stone type. A region-growing method was developed to improve the ability to differentiate between UA and non-UA stones with iodinated contrast medium. The sensitivity for detecting UA stones was 100 % for unenhanced images but fell to 18 % with 20 mgI/ml iodine solution and 0 % for higher concentrations. With region growing, the sensitivity for detecting UA stones was increased to 100 %, 82 %, 57 %, 50 % and 21 % for iodine solutions of 20, 40, 60, 80 and 100 mgI/ml. The region-growing method improves differentiation of UA from non-UA stones on contrast-enhanced DECT urograms. (orig.)

  6. G-parity violation of weak nucleon current and in-medium mass renormalization of nucleons detected through the beta decays of spin aligned sup 1 sup 2 B and sup 1 sup 2 N

    CERN Document Server

    Minamisono, K; Sumikama, T; Nagatomo, T; Matsuta, K; Minamisono, T; Fukuda, M; Koshigiri, K; Morita, M

    2000-01-01

    The beta-ray angular distributions from purely spin aligned sup 1 sup 2 B and sup 1 sup 2 N were precisely measured to determine a new limit of the G-parity irregular induced tensor form factor in weak nucleon axial vector currents and to study the in-medium mass renormalization of nucleons through the axial charge. Since the major systematic error in the previous result which originated from the intensity fluctuation of the incident beam used for the production of the nuclei was removed in the present measurement, the more reliable result was obtained: 0.01 <= 2M f sub T /f sub A <= 0.34 (90 % CL). The result is consistent with the theoretical prediction in the framework of which induced tensor form factor is proportional to the mass difference between the up and down quarks. We also determined the axial charge of the weak nucleon current to be y = 4.66 +- 0.12, which may disclose an in-medium mass reduction of the decaying nucleon of 11 +- 4 %.

  7. Heavy-flavor production and medium properties in high-energy nuclear collisions. What next?

    Energy Technology Data Exchange (ETDEWEB)

    Aarts, G.; Allton, C. [Swansea University, Swansea (United Kingdom); Aichelin, J.; Gossiaux, P.B.; Nahrgang, M. [Universite de Nantes, SUBATECH, Ecole des Mines de Nantes, Nantes (France); Arnaldi, R.; Scomparin, E. [INFN, Sezione di Torino, Torino (Italy); Bass, S.A. [Duke University, Durham, NC (United States); Bedda, C.; Grelli, A.; Trzeciak, B.; Doremalen, L. van; Vermunt, L.; Vigolo, S. [Utrecht University, Institute for Subatomic Physics, Utrecht (Netherlands); Brambilla, N. [Technische Universitaet Muenchen, Physik-Department and Excellence Cluster Universe, Garching (Germany); Technische Universitaet Muenchen, Institute for Advanced Study, Munich (Germany); Bratkovskaya, E. [GSI Helmholtzzentrum fuer Schwerionenforschung, Research Division and ExtreMe Matter Institute EMMI, Darmstadt (Germany); Frankfurt University, Institute for Theoretical Physics, Frankfurt am Main (Germany); Braun-Munzinger, P. [GSI Helmholtzzentrum fuer Schwerionenforschung, Research Division and ExtreMe Matter Institute EMMI, Darmstadt (Germany); Ruprecht-Karls-Universitaet Heidelberg, Physikalisches Institut, Heidelberg (Germany); Bruno, G.E. [Dipartimento di Fisica and INFN, Bari (Italy); European Organization for Nuclear Research, Geneva (Switzerland); Dahms, T. [Technische Universitaet Muenchen, Physik-Department and Excellence Cluster Universe, Garching (Germany); Das, S.K. [University of Catania, Catania (Italy); Dembinski, H.; Schmelling, M. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Djordjevic, M. [University of Belgrade, Institute of Physics, Belgrade (Serbia); Ferreiro, E. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Frawley, A. [Florida State University, Tallahassee, FL (United States); Granier de Cassagnac, R.; Jo, M.; Nguyen, M. [Ecole Polytechnique, Laboratoire Leprince-Ringuet, Palaiseau (France); He, M. [Nanjing University of Science and Technology, Department of Applied Physics, Nanjing (China); Horowitz, W.A. [University of Cape Town, Department of Physics, Rondebosch (South Africa); Innocenti, G.M. [Massachusetts Institute of Technology, Cambridge, MA (United States); Kaczmarek, O. [Key Laboratory of Quark and Lepton Physics (MOE) and Institute of Particle Physics, Central China Normal University, Wuhan (China); University of Bielefeld, Bielefeld (Germany); Kuijer, P.G. [National Institute for Subatomic Physics, Amsterdam (Netherlands); Laine, M. [University of Bern, AEC, Institute for Theoretical Physics, Bern (Switzerland); Lombardo, M.P. [INFN - Laboratori Nazionali di Frascati, Frascati (Italy); Mischke, A. [Utrecht University, Institute for Subatomic Physics, Utrecht (Netherlands); National Institute for Subatomic Physics, Amsterdam (Netherlands); Munhoz, M.G.; Suaide, A.A.P. [Universidade de Sao Paulo (USP), Sao Paulo (Brazil); Oliveira da Silva, A.C.; Zanoli, H.J.C. [Utrecht University, Institute for Subatomic Physics, Utrecht (Netherlands); Universidade de Sao Paulo (USP), Sao Paulo (Brazil); Petreczky, P. [Brookhaven National Laboratory, Upton, NY (United States); Rothkopf, A. [Ruprecht-Karls-Universitaet Heidelberg, Institute for Theoretical Physics, Heidelberg (Germany); Song, T. [Frankfurt University, Institute for Theoretical Physics, Frankfurt am Main (Germany); Stachel, J. [Ruprecht-Karls-Universitaet Heidelberg, Physikalisches Institut, Heidelberg (Germany); Tolos, L. [Frankfurt Institute for Advanced Studies (FIAS), Frankfurt (Germany); Institut de Ciencies de l' Espai (IEEC-CSIC), Bellaterra (Spain); Uras, A. [Domaine Scientifique de la Doua, Institute of Nuclear Physics, Villeurbanne Cedex (France); Xu, N. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Ye, Z. [University of Illinois, Chicago, IL (United States); Zhuang, P. [Tsinghua University, Beijng Shi (China)

    2017-05-15

    Open and hidden heavy-flavor physics in high-energy nuclear collisions are entering a new and exciting stage towards reaching a clearer understanding of the new experimental results with the possibility to link them directly to the advancement in lattice Quantum Chromo-Dynamics (QCD). Recent results from experiments and theoretical developments regarding open and hidden heavy-flavor dynamics have been debated at the Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, which was held in October 2016 in Leiden, The Netherlands. In this contribution, we summarize identified common understandings and developed strategies for the upcoming five years, which aim at achieving a profound knowledge of the dynamical properties of the quark-gluon plasma. (orig.)

  8. Contributions to the second workshop on medium energy electron cooling -MEEC96

    International Nuclear Information System (INIS)

    MacLachlan, J.

    1997-09-01

    MEEC96 was a workshop devoted primarily to discussion within four working groups, not a mini-conference of prepared reports. Therefore, although there are contributions bearing the name of a single author, much of what was learned came in extemporaneous discussion of the issues posed to the participants. The original plan to produce formal proceedings has been dropped because of the limited number of participants willing to write up their own contributions and because of the difficulty of converting free-wheeling discussion to the written word. The premsise for the 1996 gathering was to set a critique of Fermilab''s R ampersand D effort at cooling a ring of 8 GeV bar p''s. Separate abstracts have been submitted to the energy database for contributions to this workshop

  9. Magnesium fluoride as energy storage medium for spacecraft solar thermal power systems

    Science.gov (United States)

    Lurio, Charles A.

    1992-01-01

    MgF2 was investigated as a phase-change energy-storage material for LEO power systems using solar heat to run thermal cycles. It provides a high heat of fusion per unit mass at a high melting point (1536 K). Theoretical evaluation showed the basic chemical compatibility of liquid MgF2 with refractory metals at 1600 K, though transient high pressures of H2 can occur in a closed container due to reaction with residual moisture. The compatibility was tested in two refractory metal containers for over 2000 h. Some showed no deterioration, while there was evidence that the fluoride reacted with hafnium in others. Corollary tests showed that the MgF2 supercooled by 10-30 K and 50-90 K.

  10. Astrophysical interpretation of the medium scale clustering in the ultrahigh energy sky

    Energy Technology Data Exchange (ETDEWEB)

    Cuoco, A. [Institut for Fysik og Astronomi, Aarhus Universitet Ny Munkegade, Bygn. 1520 8000 Aarhus (Denmark)], E-mail: cuoco@phys.au.dk; Miele, G. [Universita ' Federico II' , Dipartimento di Scienze Fisiche, Napoli (Italy) and INFN Sezione di Napoli (Italy); Instituto de Fisica Corpuscular (CSIC-Universitat de Valencia), Ed. Institutos de Investigacion, Apdo. 22085, E-46071 Valencia (Spain); Serpico, P.D. [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 (United States)

    2008-02-28

    We compare the clustering properties of the combined dataset of ultra-high energy cosmic rays events, reported by the AGASA, HiRes, Yakutsk and SUGAR Collaborations, with a catalogue of galaxies of the local universe (redshift z{<=}0.06). We find that the data reproduce particularly well the clustering properties of the nearby universe within z{<=}0.02. There is no statistically significant cross-correlation between data and structures, although intriguingly the nominal cross-correlation chance probability drops from O(50%) to O(10%) using the catalogue with a smaller horizon. Also, we discuss the impact on the robustness of the results of deflections in some galactic magnetic field models used in the literature. These results suggest a relevant role of magnetic fields (possibly extragalactic ones, too) and/or possibly some heavy nuclei fraction in the UHECRs. The importance of a confirmation of these hints (and of some of their implications) by Auger data is emphasized.

  11. Theoretical aspects of electroweak and other interactions in medium energy physics

    International Nuclear Information System (INIS)

    Mukhopadhyay, N.C.

    1990-01-01

    The project, supported by the Department of Energy grant, deals with the theory of electroweak and other interactions of nucleons and nuclei, with emphasis on the electromagnetic production of mesons, and the theory of hadron structure inspired by quantum chromodynamics. On these topics, twenty-seven papers and other scientific communications have been completed during the current project period, April 1988 to present, including a number of invited papers presented at international meetings and workshops. One student has got his Ph.D. degree, and two working toward it; the latter have been rewarded by the organizers of the PANIC-XII Conference at MIT (June 1990) with financial support to present their papers A DEC-3100 workstation has been installed for the dedicated use of this project, and it has been upgraded with additional funding from Rensselaer and Digital Equipment Corporation. A new research collaboration with Professor F. Iachello, a theorist from Yale University has been started

  12. Spin-off wind energy. A study on the economic, sustainability and regional effects of wind energy

    International Nuclear Information System (INIS)

    Terbijhe, A.; Oltmer, K.; Van der Voort, M.

    2009-09-01

    This study focuses on collecting and organizing information. This information can be used as the basis for a policy line by the Dutch Ministry of Agriculture, Nature and Food Quality (LNV) for wind energy in agricultural companies. The aim of the project is to gain insight in: (1) the possible role of agricultural wind energy in the national energy supply; (2) the current and future business economic effects of wind energy on the agricultural farm; and (3) the current and future effect of wind energy on the local rural economy in general and specifically the economic meaning of wind energy for the regional economy in the region of Flevoland. [nl

  13. Production of complex particles in low energy spallation and in fragmentation reactions by in-medium random clusterization

    International Nuclear Information System (INIS)

    Lacroix, D.; Durand, D.

    2005-09-01

    Rules for in-medium complex particle production in nuclear reactions are proposed. These rules have been implemented in two models to simulate nucleon-nucleus and nucleus-nucleus reactions around the Fermi energy. Our work emphasizes the effect of randomness in cluster formation, the importance of the nucleonic Fermi motion as well as the role of conservation laws. The concepts of total available phase-space and explored phase-space under constraint imposed by the reaction are clarified. The compatibility of experimental observations with a random clusterization is illustrated in a schematic scenario of a proton-nucleus collision. The role of randomness under constraint is also illustrated in the nucleus-nucleus case. (authors)

  14. Intercomparison of the medium energy primary standards for X-ray exposure of NPL and ENEA, Italy

    International Nuclear Information System (INIS)

    Moretti, C.J.; Heaton, J.A.; Laitano, R.F.; Toni, M.P.

    1991-04-01

    An intercomparison between the primary standards of exposure for medium energy X-rays held by the National Physical Laboratory (NPL) and ENEA in Italy is described. The intercomparison, using four different transfer chambers, took place at NPL in December 1989 and at ENEA during March 1990. Measurements were made at four therapy-level qualities, with half value layers of 0.15, 0.5, 1.0 and 2.5 mm Cu (nominal generating voltages of 100, 135, 180 and 250 kV respectively). At the 2.5 mm Cu HVL quality the primary standards were found to agree to within about 0.8%; for the other three qualities the chambers differed by no more than 0.3%. (author)

  15. MuSAE: A European Project for the Diffusion of Energy and Environmental Planning in Small-Medium Sized Municipalities

    Directory of Open Access Journals (Sweden)

    Giorgio Baldinelli

    2015-12-01

    Full Text Available The basic idea of the EU LIFE+ 2011 project MuSAE (“Municipalities Subsidiarity for Actions on Energy”, code LIFE11 ENV/IT/000016 consists of transferring the skills and experience related to energy planning, acquired by the leading beneficiary, the Municipality of Perugia, to three small- or medium-sized Umbrian Municipalities (Marsciano, Umbertide and Lisciano Niccone. This transfer is aimed, among other objectives, at the drafting of the Municipal Energy and Environmental Plan (MEEP and the opening of an energy information office in each partner Municipality, in cooperation with CIRIAF and Umbria Region. The present paper provides a summary of MuSAE activities, analyzing the procedures and modalities of implementation of the various phases of the MEEPs, on the basis of the experience gained over the years through the collaboration with the Municipality of Perugia and adapted to smaller territories such as those represented by the other partner Municipalities. A summary of the dissemination activities and pilot projects is also presented, testifying the first concrete results of the planning activity developed by each administration within the project.

  16. Use of nuclear photoemulsions for low energy deuteron detection in vacuum and helium medium in case of time exposure

    International Nuclear Information System (INIS)

    Barit, I.Ya.; Balashko, Yu.G.; Dul'kova, L.S.; Zavarzina, V.P.; Romanova, T.A.

    1975-01-01

    An investigation is described of a possibility of recording 700 to 950 keV deuterons with fine-grain type T-3 and P-9 photoemulsion in vacuum and in a helium atmosphere, allowance being made for a possible variation in photolayer parameters during long exposures of an 10 to 14 days. To eliminate the exfoliation of emulsions from the glass as a result of staying for long in vacuum, they have been first kept in an spirit-glycerine mixture and then dried in a special drier at room temperature. Such pretreatment may result in changes in photoemulsion moderating capability as well as in the shrinkage coefficient. Therefore the moderating capability and the shrinkage coefficients of the photoemulsions treated by the method described above have been estimated. The obtained results show that the treatment with spirit-glycerine mixture may cause an increse in track length not more than by 1.5 to 3%, if at all, this value being within the accuracy limits of track measurements. The shrinkage coefficient for plates soaked with spirit-glycerine mixture turns out to be equal to that of untreated ones. Investigation of a possible change in emulsion layer thickness during long exposure in helium atmosphere (240 hours) and in vacuum (approximately 100 hours) show a 15% decrease in the shrinkage coefficient. Investigation of the effect of long staying of plates in vacuum and dry helium atmosphere indicates the decrease in track length due to pumping various additives the emulsions contain. The investigation carried out proves the possibility of using types T-3 and P-9 nuclear emulsions for recording low-energy charged particles at long exposures in vacuum (approximately 0.01 torr) and a dry neutral gas medium accounting for possible changes in the photolayer nuclear emulsions for recording low-energy charged particles at long exposures in vacuum (approximately 0.01 torr) and a dry neutral gas medium accounting for possible changes in the photolayer [ru

  17. Modeling of GE Appliances: Cost Benefit Study of Smart Appliances in Wholesale Energy, Frequency Regulation, and Spinning Reserve Markets

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Jason C.; Parker, Graham B.

    2012-12-31

    This report is the second in a series of three reports describing the potential of GE’s DR-enabled appliances to provide benefits to the utility grid. The first report described the modeling methodology used to represent the GE appliances in the GridLAB-D simulation environment and the estimated potential for peak demand reduction at various deployment levels. The third report will explore the technical capability of aggregated group actions to positively impact grid stability, including frequency and voltage regulation and spinning reserves, and the impacts on distribution feeder voltage regulation, including mitigation of fluctuations caused by high penetration of photovoltaic distributed generation. In this report, a series of analytical methods were presented to estimate the potential cost benefit of smart appliances while utilizing demand response. Previous work estimated the potential technical benefit (i.e., peak reduction) of smart appliances, while this report focuses on the monetary value of that participation. The effects on wholesale energy cost and possible additional revenue available by participating in frequency regulation and spinning reserve markets were explored.

  18. Energy spectra in $p$-shell $\\Lambda$ hypernuclei and $^{19}_{\\Lambda}\\textrm{F}$ and spin-dependent $\\Lambda N$ interactions

    OpenAIRE

    Kanada-En'yo, Yoshiko; Isaka, Masahiro; Motoba, Toshio

    2018-01-01

    Energy spectra of $0s$-orbit $\\Lambda$ states in $p$-shell $\\Lambda$ hypernuclei ($^{A}_\\Lambda Z$) and those in $^{19}_{\\Lambda}\\textrm{F}$ are studied with the microscopic cluster model and antisymmetrized molecular dynamics using the $G$-matrix effective $\\Lambda N$ ($\\Lambda NG$) interactions. Spin-dependent terms of the ESC08a version of the $\\Lambda NG$ interactions are tested and phenomenologically tuned to reproduce observed energy spectra in $p$-shell $^{A}_\\Lambda Z$. Spin-dependent...

  19. Medium energy electron cooling R and D at Fermilab -- Context and status

    International Nuclear Information System (INIS)

    MacLachlan, J.A.

    1996-05-01

    Electron cooling at the proposed Recycler 8 GeV storage ring has been identified as a key element in exploiting the capacity of the Fermilab Main Injector for an additional factor of ten in Tevatron luminosity above the goal for the next collider run, ultimately to > 10 33 cm -2 s -1 . The most basic requirement for increased luminosity is a large stack of antiprotons cooled to emittance comparable to that of the proton beam. Although electron cooling is inferior to the stochastic technique for cooling large emittance beams, its rate is practically independent of the antiproton intensity. For cooling intense beams of low or moderate emittance, electron cooling excels. The realization of electron cooling for 8 GeV antiprotons requires major extension of existing practice in electron energy and length of the cooling interaction region. It will require 4.3 MeV dc electron beam maintaining high quality and precise collinearity with the antiprotons over a 66 m straight section. The initial goal of the R and D project is 200 mA electron current in about three years; the plan is to reach 2 A over the following three years

  20. Medium-energy theory group. Progress report, July 1, 1976--June 30, 1977

    International Nuclear Information System (INIS)

    Bryan, R.A.

    1977-05-01

    Research carried out during the contract period by R. A. Bryan, principal investigator, and associates R. B. Clark and B. J. VerWest is reported. Most of the work has centered on the nucleon-nucleon interaction at low to intermediate energies and has ranged from purely theoretical studies, such as the behavior of two-pion-exchange Feynman amplitudes at far off-shell initial and final nucleon momenta, to the more practical work of phase-shift analyzing nucleon-nucleon data. One has also investigated the possibility that the NN interaction is not invariant under time-reversal and have provided predictions for some relevant experimental observables for the case where such time-irreversibility is due to short-range processes. Finally, research on topics which fall in the domain of elementary-particle physics but which are felt can lend guidance in trying to determine the NN force at very short distances is completed; this is the current frontier in nucleon-nucleon research. A list of publications is included

  1. Investigations of Few-Nucleon System Dynamics in Medium Energy Domain

    Science.gov (United States)

    Ciepał, I.; Kłos, B.; Kistryn, St.; Stephan, E.; Biegun, A.; Bodek, K.; Deltuva, A.; Epelbaum, E.; Eslami-Kalantari, M.; Fonseca, A. C.; Golak, J.; Jha, V.; Kalantar-Nayestanaki, N.; Kamada, H.; Khatri, G.; Kirillov, Da.; Kirillov, Di.; Kliczewski, St.; Kozela, A.; Kravcikova, M.; Machner, H.; Magiera, A.; Martinska, G.; Messchendorp, J.; Nogga, A.; Parol, W.; Ramazani-Moghaddam-Arani, A.; Roy, B. J.; Sakai, H.; Sekiguchi, K.; Sitnik, I.; Siudak, R.; Skibiński, R.; Sworst, R.; Urban, J.; Witała, H.; Wrońska, A.; Zejma, J.

    2013-08-01

    Precise and large set of cross sections, vector A x , A y and tensor A xx , A xy , A yy analyzing powers for the 1 H( d, pp) n breakup reactions were measured at 100 and 130 MeV deuteron beam energies with the use of the SALAD and BINA detectors at KVI and Germanium Wall setup at FZ-Jülich. Results are compared with various theoretical approaches which model the three-nucleon (3N) system dynamics. The calculations are based on different two-nucleon (2N) potentials which can be combined with models of the three-nucleon force (3NF) and other pieces of the dynamics can also be included like the Coulomb interaction and relativistic effects. The cross sections data reveal seizable 3NF and Coulomb force influence. In case of analyzing powers very low sensitivity to the effects was found and the data are well describe by 2N models only. At 130 MeV for A xy serious disagreements appear when 3NF models are included into calculations.

  2. Investigations of Few-Nucleon System Dynamics in Medium Energy Domain

    International Nuclear Information System (INIS)

    Ciepał, I.; Kistryn, St.; Biegun, A.; Bodek, K.; Golak, J.; Khatri, G.; Magiera, A.; Parol, W.; Skibiński, R.; Sworst, R.; Witała, H.; Wrońska, A.; Zejma, J.; Kłos, B.; Stephan, E.; Kozela, A.; Kliczewski, St.; Siudak, R.; Eslami-Kalantari, M.; Ramazani-Moghaddam-Arani, A.; Kalantar-Nayestanaki, N.; Messchendorp, J.; Machner, H.; Nogga, A.; Epelbaum, E.; Deltuva, A.; Fonseca, A. C.; Kamada, H.; Jha, V.; Kirillov, Da.; Kirillov, Di.; Sitnik, I.; Kravcikova, M.; Martinska, G.; Urban, J.; Roy, B.J.; Sakai, H.; Sekiguchi, K.

    2013-01-01

    Precise and large set of cross sections, vector A x , A y and tensor A xx , A xy , A yy analyzing powers for the 1 H(d, pp)n breakup reactions were measured at 100 and 130 MeV deuteron beam energies with the use of the SALAD and BINA detectors at KVI and Germanium Wall setup at FZ-Jülich. Results are compared with various theoretical approaches which model the three-nucleon (3N) system dynamics. The calculations are based on different two-nucleon (2N) potentials which can be combined with models of the three-nucleon force (3NF) and other pieces of the dynamics can also be included like the Coulomb interaction and relativistic effects. The cross sections data reveal seizable 3NF and Coulomb force influence. In case of analyzing powers very low sensitivity to the effects was found and the data are well describe by 2N models only. At 130 MeV for A xy serious disagreements appear when 3NF models are included into calculations. (author)

  3. A spin-filter polarimeter for low energy hydrogen and deuterium ion beams

    International Nuclear Information System (INIS)

    Lemieux, S.K.; Clegg, T.B.; Karwowski, H.J.; Thompson, W.J.; Crosson, E.R.

    1993-01-01

    An efficient polarimeter which reveals populations of individual hyperfine states of nuclear-spin-polarized H ± (or D ± ) ion beams has been tested. This device is based on unique properties of a three-level interaction in the 2S 1/2 and 2P 1/2 states of hydrogen (or deuterium) atoms, created when the incident, polarized ion beams undergo electron pickup in cesium vapour. Used on a polarized ion source, its efficiency faciy facilitates both rapid optimization and continual monitoring of parameters that affect the beam polarization. With such sources, and perhaps in applications with polarized gas jet targets, the device has potential for an absolute accuracy of better than 2%. (orig.)

  4. Relative response of the alanine dosimeter to medium energy x-rays.

    Science.gov (United States)

    Anton, M; Büermann, L

    2015-08-07

    The response of the alanine dosimeter to kilovoltage x-rays with respect to the dose to water was measured, relative to the response to Co-60 radiation.Two series of x-ray qualities were investigated, one ranging from 30 kV to 100 kV tube voltage (TW series), the other one ranging from 70 kV to 280 kV (TH series). Due to the use of the water calorimeter as a primary standard, the uncertainty of the delivered dose is significantly lower than for other published data. The alanine response was measured as described in a previous publication (Anton et al 2013 Phys. Med. Biol. 58 3259-82). The uncertainty component due to the alanine measurement and analysis is ⩽0.4%, the major part of the combined uncertainty of the relative response originates from the uncertainty of the delivered dose. The relative uncertainties of the relative response vary from ⩽2% for the TW series to ⩽1.1% for the TH series.Different from the behaviour of the alanine dosimeter for megavoltage x-rays or electrons, the relative response drops significantly from unity for Co-60 radiation to less than 64% for the TW quality with a tube voltage of 30 kV. In order to reproduce this behaviour through Monte Carlo simulations, not only the ratio of the absorbed dose to alanine to the absorbed dose to water has to be known, but also the intrinsic efficiency, i.e. the dependence of the number of free radicals generated per unit of absorbed dose on the photon energy. This quantity is not yet accessible for the TW series.For a possible use of the alanine dosimeter for kilovoltage x-rays, for example in electronic brachytherapy, users should rely on the measured data for the relative response which have become available with this publication.

  5. Low energy nuclear spin excitations in Ho metal investigated by high resolution neutron spectroscopy.

    Science.gov (United States)

    Chatterji, Tapan; Jalarvo, Niina

    2013-04-17

    We have investigated the low energy excitations in metallic Ho by high resolution neutron spectroscopy. We found at T = 3 K clear inelastic peaks in the energy loss and energy gain sides, along with the central elastic peak. The energy of this low energy excitation, which is 26.59 ± 0.02 μeV at T = 3 K, decreased continuously and became zero at TN ≈ 130 K. By fitting the data in the temperature range 100-127.5 K with a power law we obtained the power-law exponent β = 0.37 ± 0.02, which agrees with the expected value β = 0.367 for a three-dimensional Heisenberg model. Thus the energy of the low energy excitations can be associated with the order parameter.

  6. Direct observation of low energy nuclear spin excitations in HoCrO3 by high resolution neutron spectroscopy.

    Science.gov (United States)

    Chatterji, T; Jalarvo, N; Kumar, C M N; Xiao, Y; Brückel, Th

    2013-07-17

    We have investigated low energy nuclear spin excitations in the strongly correlated electron compound HoCrO3. We observe clear inelastic peaks at E = 22.18 ± 0.04 μeV in both energy loss and gain sides. The energy of the inelastic peaks remains constant in the temperature range 1.5-40 K at which they are observed. The intensity of the inelastic peak increases at first with increasing temperature and then decreases at higher temperatures. The temperature dependence of the energy and intensity of the inelastic peaks is very unusual compared to that observed in other Nd, Co, V and also simple Ho compounds. Huge quasielastic scattering appears at higher temperatures presumably due to the fluctuating electronic moments of the Ho ions that get increasingly disordered at higher temperatures. The strong quasielastic scattering may also originate in the first Ho crystal-field excitations at about 1.5 meV.

  7. Contribution to the determination of the double angular and energy differential neutron albedo. Application to the propagation in lacunar medium

    International Nuclear Information System (INIS)

    Litaize, O.

    2000-01-01

    The goal of this thesis is to study the neutron propagation by reflection from lacunar medium interfaces. The most efficient method to calculate this type of propagation is to use the concept of albedo. Actual version of NARCISSE code uses a simple formulation of angular differential albedos and so, can only treat single reflections. Multiple reflections treatment needs the knowledge of neutron spectrum after reflection. This energetic information is contained in double angular and energy differential albedos. The first step of this study consists to generate these albedos for various materials. Several methods have been tested and the Monte Carlo method was retained. A new estimator has been developed and validated in the Mote Carlo transport code TRIPOLI-4. It computes, during the simulation of the neutron history, the angular and energy reflection probability at each collision site. The second step consists to generate an interpolation scheme and albedo libraries for various materials. A new version of NARCISSE was developed to use these libraries and the interpolation module. Spectrum and dose rates comparisons were made between codes to validate these albedos. The neutron propagation by multiple reflections can be studied now, by using this new version of Narcisse. (author)

  8. Electromagnetic design and development of a combined function horizontal and vertical dipole steerer magnet for medium energy beam transport line

    International Nuclear Information System (INIS)

    Singh, Kumud; Itteera, Janvin; Ukarde, Priti; Teotia, Vikas; Kumar, Prashant; Malhotra, Sanjay; Taly, Y.K.

    2013-01-01

    Medium Energy Beam Transport (MEBT) line is required to match the optical functions between the RFQ and SRF cavities/DTL cavities.The primary function of the MEBT lines is to keep the emittance growth of the output beam as low as possible in a highly space charge environment at low energies. The transverse focusing of the beam is achieved by strong focusing quadrupoles and the longitudinal dynamics is achieved by the buncher cavities. The Dipole Steerers serve the function of a control element to achieve the desired transverse beam position. To minimize the emittance growth high magnetic field rigidity is required in a highly constrained longitudinal space for these corrector magnets. The design and development of an air-cooled dipole steerer magnet has been done for an integral dipole field of 2.1mT-m in a Good Field Region (GFR) of 23 mm diameter with Integral Field homogeneity better than 0.5%. Electromagnetic field simulations were done using 3D-FEM simulation software OPERA. Error sensitivity studies have been carried out to specify the manufacturing tolerances to estimate and minimize the beam transmission loss due to likely misalignments and rotation of the magnet. A combined function dipole corrector magnet has been designed and fabricated at the Control Instrumentation Division, BARC. This paper discusses measurement results of a combined function dipole steerer for MEBT line for Proton (H + ) beam at 2.5 MeV. (author)

  9. Radiosensitivity of chlorella after medium energy accelerated electron irradiation; Radiosensibilite des chlorelles aux electrons acceleres de moyenne energie

    Energy Technology Data Exchange (ETDEWEB)

    Roux, J C [commissariat a L' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1966-06-01

    The survival curves (capability of multiplication) of chlorella pyrenoidosa after irradiations can be used for soft electrons (0.65 and 1 MeV), hence penetrating into only 2 to 4 millimeters of water: the algae are laying on porous membranes and the doses are calculated from the power of the electron beam measured by the electric current on a metallic target or by Fricke's dosimetry. With these techniques, it is showed and discussed the part of anoxia in the radioprotection (magnitude or reduction of the dose calculated from the slope of survival curves: 2.5 ) that is more important than the restoration studied by the fractionation of the dose. The 0.65 and 1 MeV electrons have a biologic effect lesser than 180 keV X-rays (RBE - relative biological efficiency - calculated on the slope of survival curves is 0.92 in aerated irradiation, 0.56 in the deoxygenated irradiation). (author) [French] Les courbes de survie clonale (capacite de multiplication) de chlorella pyrenoidosa apres irradiation sont realisables meme avec des electrons peu energetiques (0.65 et 1 MeV), donc peu penetrants, par l'irradiation d'algues deposees sur membrane filtrante et grace au calcul de la dose a partir de l'energie du faisceau mesure par le courant que celui-ci cree dans une cible metallique ou par dosimetrie de Fricke. Par ces techniques, on a montre et discute le role de l'anoxie dans la radioprotection des chlorelles (facteur de reduction de la dose calcule sur la pente des courbes de survie de 2.5) qui est plus important que le pouvoir de restauration etudie par le fractionnement de la dose. Les electrons utilises ont un effet biologique moins grand que les rayons X de 180 keV (l'efficacite biologique relative - EBR - calculee sur la pente des courbes de survie est de 0.9 en presence d'air, 0.6 en presence d'azote)

  10. High spin spectroscopy near the N=Z line: Channel selection and excitation energy systematics

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, C.E.; Cameron, J.A.; Flibotte, S. [McMaster Univ., Ontario (Canada)] [and others

    1996-12-31

    The total {gamma}-ray and charged-particle energies emitted in fusion-evaporation reactions leading to N=Z compound systems in the A = 50-70 mass region have been measured with the 8{pi} {gamma}-ray spectrometer and the miniball charged-particle detector array. A new method of channel selection has been developed which combines particle identification with these total energy measurements and greatly improves upon the selectivity possible with particle detection alone. In addition, the event by event measurement of total {gamma}-ray energies using the BGO ball of the 8{pi} spectrometer has allowed a determination of excitation energies following particle evaporation for a large number of channels in several different reactions. The new channel selection procedure and excitation energy systematics are illustrated with data from the reaction of {sup 24}Mg on {sup 40}Ca at E{sub lab} = 80MeV.

  11. X-ray diffraction study of stress relaxation in cubic boron nitride films grown with simultaneous medium-energy ion bombardment

    International Nuclear Information System (INIS)

    Abendroth, B.; Gago, R.; Eichhorn, F.; Moeller, W.

    2004-01-01

    Relaxation of the intrinsic stress of cubic boron nitride (cBN) thin films has been studied by x-ray diffraction (XRD) using synchrotron light. The stress relaxation has been attained by simultaneous medium-energy ion bombardment (2-10 keV) during magnetron sputter deposition, and was confirmed macroscopically by substrate curvature measurements. In order to investigate the stress-release mechanisms, XRD measurements were performed in in-plane and out-of-plane geometry. The analysis shows a pronounced biaxial state of compressive stress in the cBN films grown without medium-energy ion bombardment. This stress is partially released during the medium-energy ion bombardment. It is suggested that the main path for stress relaxation is the elimination of strain within the cBN grains due to annealing of interstitials

  12. Elasto-dynamic analysis of spinning nanodisks via a surface energy-based model

    Science.gov (United States)

    Kiani, Keivan

    2016-07-01

    Using the surface elasticity theory of Gurtin and Murdoch, in-plane vibrations of annular nanodisks due to their rotary motion are explored. By the imposition of non-classical boundary conditions on the innermost and outermost surfaces and employing Hamilton’s principle, the unknown elasto-dynamic fields of the bulk zone are determined via the finite element method. The roles of both nanodisk geometry and surface effect on the natural frequencies are addressed. Subsequently, forced vibrations of spinning nanodisks with fixed-free and free-free boundary conditions are comprehensively examined. The obtained results show that the maximum dynamic elastic fields grow in a parabolic manner as the steady angular velocity increases. By increasing the outermost radius, the maximum dynamic elastic field is magnified and the influence of the surface effect on the results reduced. This work can be considered as a pivotal step towards optimal design and dynamic analysis of nanorotors with disk-like parts, which are one of the basic building blocks of the upcoming advanced nanotechnologies.

  13. Projection of primary energy in electricity generation with evaluation of demand and supply of energy in the medium-term horizon (2020), long-term (2035) and very long term (2060)

    International Nuclear Information System (INIS)

    Mafra, Olga Y.; Alvim, Carlos Feu; Eidelman, Frida; Guimaraes, Leonam dos Santos

    2013-01-01

    The Global Energy demand and the participation of electricity in scenarios of medium (2020), long (2035) and very long (2060) terms are estimated. It is also evaluated the share of different primary energies in electricity generation and their availability in the country. Three economic scenarios were considered and different hypothesis regarding the participation of nuclear energy were analyzed. (author)

  14. Energy-Efficiency Analysis of a Distributed Queuing Medium Access Control Protocol for Biomedical Wireless Sensor Networks in Saturation Conditions

    Directory of Open Access Journals (Sweden)

    Christos Verikoukis

    2011-01-01

    Full Text Available The aging population and the high quality of life expectations in our society lead to the need of more efficient and affordable healthcare solutions. For this reason, this paper aims for the optimization of Medium Access Control (MAC protocols for biomedical wireless sensor networks or wireless Body Sensor Networks (BSNs. The hereby presented schemes always have in mind the efficient management of channel resources and the overall minimization of sensors’ energy consumption in order to prolong sensors’ battery life. The fact that the IEEE 802.15.4 MAC does not fully satisfy BSN requirements highlights the need for the design of new scalable MAC solutions, which guarantee low-power consumption to the maximum number of body sensors in high density areas (i.e., in saturation conditions. In order to emphasize IEEE 802.15.4 MAC limitations, this article presents a detailed overview of this de facto standard for Wireless Sensor Networks (WSNs, which serves as a link for the introduction and initial description of our here proposed Distributed Queuing (DQ MAC protocol for BSN scenarios. Within this framework, an extensive DQ MAC energy-consumption analysis in saturation conditions is presented to be able to evaluate its performance in relation to IEEE 802.5.4 MAC in highly dense BSNs. The obtained results show that the proposed scheme outperforms IEEE 802.15.4 MAC in average energy consumption per information bit, thus providing a better overall performance that scales appropriately to BSNs under high traffic conditions. These benefits are obtained by eliminating back-off periods and collisions in data packet transmissions, while minimizing the control overhead.

  15. CERN: LEP delivers; Looking deeper at spin; Handling low energy antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1990-03-15

    One year ago, with the world catalogue of Z particles - the electrically neutral carrier of the weak nuclear force - containing a few hundred examples, it sounded extravagant when proponents of CERN's new LEP electron-positron collider promised a hundred thousand Zs by Christmas 1989. The first round of experiments in the North Area of CERN's SPS proton synchrotron included a considerable investment in studies using high energy muon beams. This paid off with important contribuions to physics, particularly in the measurement of the quark/gluon content (structure functions) of nucleons. ; The LEAR low energy antiproton ring at CERN takes its antimatter beams down to very low kinetic energies - less than 10 MeV - for a unique range of physics studies. However even these modest energies are too high for a series of experiments aiming to explore the effects of gravity on antimatter.

  16. CERN: LEP delivers; Looking deeper at spin; Handling low energy antiprotons

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    One year ago, with the world catalogue of Z particles - the electrically neutral carrier of the weak nuclear force - containing a few hundred examples, it sounded extravagant when proponents of CERN's new LEP electron-positron collider promised a hundred thousand Zs by Christmas 1989. The first round of experiments in the North Area of CERN's SPS proton synchrotron included a considerable investment in studies using high energy muon beams. This paid off with important contribuions to physics, particularly in the measurement of the quark/gluon content (structure functions) of nucleons. ; The LEAR low energy antiproton ring at CERN takes its antimatter beams down to very low kinetic energies - less than 10 MeV - for a unique range of physics studies. However even these modest energies are too high for a series of experiments aiming to explore the effects of gravity on antimatter

  17. Experimental Medium Energy Physics

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses the following topics: Search for the H Dibaryon at the AGS; hypernuclear weak decay studies at the LAGS; search for strangelets using the 2 GeV/c beam line; experiment to detect double lambda hypernuclei; hyperon photoproduction at CEBAF; the region 1 drift chambers for the CLAS spectrometer; parity violating electron scattering from the proton: the G 0 experiment at CEBAF; and relativistic heavy ion - nucleus collisions at the SPS

  18. [Medium energy particle physics

    International Nuclear Information System (INIS)

    Nefkens, B.M.K.

    1985-10-01

    Investigations currently carried out by the UCLA Particle Physics Research Group can be arranged into four programs: Pion-Nucleon Scattering; Tests of Charge Symmetry and Isospin Invariance; Light Nuclei (Strong Form Factors of 3 H, 3 He, 4 He; Detailed Balance in pd right reversible γ 3 H; Interaction Dynamics); and Search for the Rare Decay Μ + → e + + γ (MEGA). The general considerations which led to the choice of physics problems investigated by our group are given in the next section. We also outline the scope of the research being done which includes over a dozen experiments. The main body of this report details the research carried out in the past year, the status of various experiments, and new projects

  19. Experimental medium energy physics

    International Nuclear Information System (INIS)

    1989-01-01

    This report discusses the following topics: search for the ξ(2230) at LEAR; hyperon-antihyperon production studies at LEAR; relativistic proton-nucleus and heavy ion-nucleus collisions at the SPS; search for the H dibaryon at the AGS; hypernuclear physics research; CEBAF activities; pion physics at PSI; and H particle experiment design and development

  20. Experimental medium energy physics

    International Nuclear Information System (INIS)

    Barnes, P.D.

    1990-01-01

    This report discusses the following topics: search for the H-dibaryon at the AGS; weak interaction studies with hypernuclear decays at the AGS; search for the ξ(2230) at LEAR; relativistic proton-nucleus and heavy ion-nucleus collisions at the SPS; hyperon-antihyperon production studies at LEAR; photoproduction of strange CEBAF; and experiment design development