WorldWideScience

Sample records for exchange cross sections

  1. Charge exchange cross-sections for multiply charged ions

    International Nuclear Information System (INIS)

    Midha, J.M.; Gupta, S.C.

    1990-01-01

    A new empirical relation for charge exchange cross-section has been proposed for different charge states of C, N and O colliding with neutral hydrogen. Results are compared with the experimental data. (Author)

  2. Cross sections and rate coefficients for charge exchange reactions of protons with hydrocarbon molecules

    International Nuclear Information System (INIS)

    Janev, R.K.; Kato, T.; Wang, J.G.

    2001-05-01

    The available experimental and theoretical cross section data on charge exchange processes in collisions of protons with hydrocarbon molecules have been collected and critically assessed. Using well established scaling relationships for the charge exchange cross sections at low and high collision energies, as well as the known rate coefficients for these reactions in the thermal energy region, a complete cross section database is constructed for proton-C x H y charge exchange reactions from thermal energies up to several hundreds keV for all C x H y molecules with x=1, 2, 3 and 1 ≤ y ≤ 2x + 2. Rate coefficients for these charge exchange reactions have also been calculated in the temperature range from 0.1 eV to 20 keV. (author)

  3. Cross sections and rate coefficients for charge exchange reactions of protons with hydrocarbon molecules

    Energy Technology Data Exchange (ETDEWEB)

    Janev, R.K.; Kato, T. [National Inst. for Fusion Science, Toki, Gifu (Japan); Wang, J.G. [Department of Physics and Astronomy, University of Georgia, Athens (United States)

    2001-05-01

    The available experimental and theoretical cross section data on charge exchange processes in collisions of protons with hydrocarbon molecules have been collected and critically assessed. Using well established scaling relationships for the charge exchange cross sections at low and high collision energies, as well as the known rate coefficients for these reactions in the thermal energy region, a complete cross section database is constructed for proton-C{sub x}H{sub y} charge exchange reactions from thermal energies up to several hundreds keV for all C{sub x}H{sub y} molecules with x=1, 2, 3 and 1 {<=} y {<=} 2x + 2. Rate coefficients for these charge exchange reactions have also been calculated in the temperature range from 0.1 eV to 20 keV. (author)

  4. Molecular (Feshbach) treatment of charge exchange Li3++He collisions. II. Cross sections

    International Nuclear Information System (INIS)

    Errea, L.F.; Martin, F.; Mendez, L.; Riera, A.; Yanez, M.

    1986-01-01

    Using the wave functions calculated in the preceding article, and a common translation factor, the charge exchange cross section for the Li 3+ +He(1s 2 ) reaction is calculated, and the mechanism of the process discussed. We show how small deviations from the Landau--Zener model, which are unrelated to Nikitin's conditions for its validity, lead to a minimum of the cross section at an impact energy Eapprox. =1 keV, and to larger values of sigma at intermediate nuclear velocities

  5. Thermal response test data of five quadratic cross section precast pile heat exchangers.

    Science.gov (United States)

    Alberdi-Pagola, Maria

    2018-06-01

    This data article comprises records from five Thermal Response Tests (TRT) of quadratic cross section pile heat exchangers. Pile heat exchangers, typically referred to as energy piles, consist of traditional foundation piles with embedded heat exchanger pipes. The data presented in this article are related to the research article entitled "Comparing heat flow models for interpretation of precast quadratic pile heat exchanger thermal response tests" (Alberdi-Pagola et al., 2018) [1]. The TRT data consists of measured inlet and outlet temperatures, fluid flow and injected heat rate recorded every 10 min. The field dataset is made available to enable model verification studies.

  6. Thermal response test data of five quadratic cross section precast pile heat exchangers

    Directory of Open Access Journals (Sweden)

    Maria Alberdi-Pagola

    2018-06-01

    Full Text Available This data article comprises records from five Thermal Response Tests (TRT of quadratic cross section pile heat exchangers. Pile heat exchangers, typically referred to as energy piles, consist of traditional foundation piles with embedded heat exchanger pipes. The data presented in this article are related to the research article entitled “Comparing heat flow models for interpretation of precast quadratic pile heat exchanger thermal response tests” (Alberdi-Pagola et al., 2018 [1]. The TRT data consists of measured inlet and outlet temperatures, fluid flow and injected heat rate recorded every 10 min. The field dataset is made available to enable model verification studies.

  7. The effect of meson exchange on the forward cross section for d(γ,p)n

    International Nuclear Information System (INIS)

    Jaus, W.; Woolcock, W.S.

    1981-01-01

    We have investigated the effect of meson exchange on the theoretical calculation of the cross section for the photodisintegration of the deuteron in the forward direction, in the hope of reducing the present large discrepancy between theory and experiment. Two recent papers reporting a significant reduction in the discrepancy were found to have a sign error; when pseudoscalar πNN coupling is used the effect of one-pion exchange is to increase the discrepancy. We have calculated the one-pion and two-pion exchange effects on the E1 transitions using pseudovector πNN coupling and the resulting correction is small and in the right direction. Thus, assuming the reliability of both theory and experiment, our calculation provides a strong argument in favour of using PV rather than PS πNN coupling in calculating meson exchange effects in nuclear processes. We have found that the effect of the exchange of rho- and ω-mesons is very small. Meson exchange effects change the normalization of the deuteron wave function and cause a further small reduction in the calculated cross section. Since the corrections to the M1 transitions are expected to be very small, it seems unlikely that meson exchange effects can account for the discrepancy between theory and experiment. (orig.)

  8. Molecular (Feshbach) treatment of charge exchange Li/sup 3 +/+He collisions. II. Cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Errea, L.F.; Martin, F.; Mendez, L.; Riera, A.; Yanez, M.

    1986-05-15

    Using the wave functions calculated in the preceding article, and a common translation factor, the charge exchange cross section for the Li/sup 3 +/+He(1s/sup 2/) reaction is calculated, and the mechanism of the process discussed. We show how small deviations from the Landau--Zener model, which are unrelated to Nikitin's conditions for its validity, lead to a minimum of the cross section at an impact energy Eapprox. =1 keV, and to larger values of sigma at intermediate nuclear velocities.

  9. Partial cross sections near the higher resonances

    International Nuclear Information System (INIS)

    Falk-Vairant, P.; Valladas, G.

    1961-07-01

    As a continuation of the report given at the 10. Rochester Conference, recent measurements of charge-exchange cross section and π 0 production in π - -p interactions are presented here. Section 1 gives a summary of the known results for the elastic, inelastic, and charge-exchange cross sections. Section 2 presents the behavior of the cross sections in the T=1/2 state, in order to discuss the resonances at 600 and 890 MeV. Section 3 discusses the charge-exchange scattering and the interference term between the T=1/2 and T=3/2 states. Section 4 presents some comments on inelastic processes. This report is reprinted from 'Reviews of Modern Physics', Vol. 33, No. 3, 362-367, July, 1961

  10. Is the quasielastic pion cross section really bigger than the pion-nucleus reaction cross section

    International Nuclear Information System (INIS)

    Silbar, R.R.

    1979-01-01

    It is shown that soft pion charge exchanges may increase the inclusive (π + ,π 0 ') cross section, relative to the total quasielastic (π + ,π + ') cross section, by as much as a factor of two. 4 references

  11. The structure of the forward elastic cross section in (10--14) GeV range. [Differential cross sections, peripheral exchange amplitude

    Energy Technology Data Exchange (ETDEWEB)

    Carnegie, R K; Cashmore, R J; Davier, M; Leith, D W.G.S.; Walden, P; Williams, S H [Stanford Linear Accelerator Center, Calif. (USA)

    1975-11-10

    The logarithmic slope of the differential cross section for K/sup + -/p elastic scattering at 10 and 14 GeV, and for ..pi../sup + -/p and p/sup + -/p at 10 GeV has been measured. Rich structure is observed in the forward slope for all processes, which is well accounted for by the properties of a peripheral exchange amplitude for the nonexotic reactions, and by a peripheral component of the diffractive amplitude as clearly seen in the exotic processes, K/sup +/p and pp.

  12. Exchange corrections to the bulk plasmon cross section of slow electrons in metals

    International Nuclear Information System (INIS)

    Yin, S.; Goodman, B.; Tosatti, E.

    1981-08-01

    We present a calculation of the simplest exchange correction to the low-energy electron cross section for plasmon creation in a free-electron-like metal with the density of Al. The resulting cancellation effect is found to be much too small to account for the anomalous delayed onset of plasmon losses, found in core level photo emission for Al. (author)

  13. Asymptotic form of the charge-exchange cross section in three-body rearrangement collisions

    Science.gov (United States)

    Omidvar, K.

    1975-01-01

    A three-body general-type rearrangement collision is considered in which the initial and final bound states are described by hydrogen-like wave functions. It is shown that the charge-exchange amplitude in the first Born approximation can be expanded at all incident energies in terms of the inverse powers of the principal quantum number (n). By expanding the exchange amplitude in this way, it is demonstrated conclusively that the cross section for capture into the s, p, and d states as well as for the sum over all the angular-momentum states is proportional to 1/n-cubed plus terms proportional to higher inverse odd powers of n. It is found that the low-lying levels cannot be scaled to the 1/n-cubed law irrespective of the value of the incident energy except in the case of capture into the s states in accordance with the Oppenheimer-Brinkman-Kramers approximation. Zeros and minima in the differential cross sections are given in the limit of high principal quantum number for electron capture by protons from atomic hydrogen and for positronium formation by proton-atomic hydrogen collisions.

  14. Line-emission cross sections for the charge-exchange reaction between fully stripped carbon and atomic hydrogen in tokamak plasma

    International Nuclear Information System (INIS)

    Ida, K.; Kato, T.

    1992-01-01

    Line-emission cross sections of the charge-exchange reaction between fully stripped carbon and atomic hydrogen are measured in the energy range of 18 - 38 keV/amu in tokamak plasmas. The energy dependence of the emission cross sections for the transition of Δn = 8 - 7 and Δn = 7 - 6 and their ratios are compared with theoretical calculations. (author)

  15. The role of charge-exchange cross-section for pickup protons and neutrals in the inner heliosheath

    Science.gov (United States)

    Chalov, S. V.

    2018-06-01

    The process of deceleration of the solar wind downstream of the termination shock is studied on the basis of a one-dimensional multi-component model. It is assumed that the solar wind consists of thermal protons, electrons and interstellar pickup protons. The protons interact with interstellar hydrogen atoms by charge-exchange. Two cases are considered. In the first one, the charge-exchange cross-section for thermal protons and hydrogen atoms is the same as for pickup protons and atoms. Under this condition, there is a strong dependence of the solar wind velocity on the downstream temperature of pickup protons. When the proton temperature is close to 10 keV, the change in the velocity with the distance from the termination shock is similar to that measured on the Voyager 1 spacecraft: linear velocity decrease is accompanied by an extended transition region with near-zero velocity. However, with a more careful approach to the choice of the charge-exchange cross-section, the situation changes dramatically. The strong dependence of the solar wind speed on the pickup proton temperature disappears and the transition region in the heliosheath disappears as well, at least at reasonable distances from the TS.

  16. Absolute Charge Exchange Cross Sections for ^3He^2+ Collisions with ^4He and H_2

    Science.gov (United States)

    Mawhorter, R. J.; Greenwood, J.; Smith, S. J.; Chutjian, A.

    2002-05-01

    The JPL charge exchange beam-line(J.B. Greenwood, et al., Phys. Rev A 63), 062707 (2001) was modified to increase the forward acceptance angle and enable the measurement of total charge-exchange cross sections for slow, light, highly-charged ion collisions with neutral targets(R. E. Olson and M. Kimura, J. Phys. B 15), 4231 (1982). Data are presented for single charge exchange cross sections for ^3He^2+ nuclei scattered by ^4He and H2 in the energy range 0.33-4.67 keV/amu. For both targets there is good agreement with Kusakabe, et al.(T. Kusakabe, et al., J. Phys. Soc. Japan 59), 1218 (1990). Angular collection is studied by a comparison with differential measurements(D. Bordenave-Montesquieu and R. Dagnac, J. Phys. B 27), 543 (1994), as well as with earlier JPL results(J.B. Greenwood, et al., Ap. J. 533), L175 (2000), ibid. 529, 605 (2000) using heavier projectiles and targets. This work was carried out at JPL/Caltech, and was supported through contract with NASA. RJM thanks the NRC for a Senior Associateship at JPL.

  17. Parametric investigation of a non-constant cross sectional area air to air heat exchanger

    International Nuclear Information System (INIS)

    Cárdenas, Bruno; Garvey, Seamus; Kantharaj, Bharath; Simpson, Michael

    2017-01-01

    Highlights: • Evaluation of complex geometry aimed at minimizing volume per unit of exergy transfer. • The use of a non-constant cross-section for the heat exchanger is proposed. • The performance gains attainable via modern manufacturing techniques are discussed. • The trade-off between overall exergy efficiency and cost is thoroughly analysed. • A quadratic proportion between volume and characteristic dimension has been found. - Abstract: The present article addresses the design, mathematical modelling and analysis of a novel highly exergy-efficient air to air heat exchanger. An intricate design based on an hexagonal mesh is proposed for the cross-sectional area of the heat exchanger with aims to explore the performance gains that can be obtained by exploiting the capabilities and benefits offered by modern fabrication techniques such as additive manufacturing. Special attention is paid to understanding the relationship or trade-off that exists between the overall exergy efficiency of the heat exchanger and its cost. The iterative algorithm used to find the geometrical parameters that yield the best performance in terms of volume of material required per unit of exergy transfer at a certain level of efficiency, as well as the assumptions and simplifications made, are comprehensively explained. It has been found through the analyses carried out performed, which are thoroughly discussed throughout the paper, that if the characteristic dimension of the heat exchanger is scaled up by a factor of n, the volume of material per kW of exergy transfer at certain exergy efficiency will increase by a factor of n squared. This is a very important observation, possibly applicable to other types of heat exchangers, that indicates that performance improves dramatically at smaller scales. The overall performance of the case study presented is satisfactory, a volume of material as low as 84.8 cm"3 for one kW of exergy transfer can be achieved with a 99% exergy

  18. Characterization of cross-section correction to charge exchange recombination spectroscopy rotation measurements using co- and counter-neutral-beam views.

    Science.gov (United States)

    Solomon, W M; Burrell, K H; Feder, R; Nagy, A; Gohil, P; Groebner, R J

    2008-10-01

    Measurements of rotation using charge exchange recombination spectroscopy can be affected by the energy dependence of the charge exchange cross section. On DIII-D, the associated correction to the rotation can exceed 100 kms at high temperatures. In reactor-relevant low rotation conditions, the correction can be several times larger than the actual plasma rotation and therefore must be carefully validated. New chords have been added to the DIII-D CER diagnostic to view the counter-neutral-beam line. The addition of these views allows determination of the toroidal rotation without depending on detailed atomic physics calculations, while also allowing experimental characterization of the atomic physics. A database of rotation comparisons from the two views shows that the calculated cross-section correction can adequately describe the measurements, although there is a tendency for "overcorrection." In cases where accuracy better than about 15% is desired, relying on calculation of the cross-section correction may be insufficient.

  19. Theoretical charge-exchange total cross sections for B+3 + He and C+4 + He collisions

    International Nuclear Information System (INIS)

    Shipsey, E.J.; Browne, J.C.; Olson, R.E.

    1977-01-01

    Charge-exchange total cross sections for the B +3 + He and C +4 + He systems have been calculated in the velocity range v = (1--10) x 10 7 cm/sec. Ab initio potential-energy curves and coupling-matrix elements were computed and employed in the impact-parameter classical-coupled equations that describe the collision to obtain the cross sections. For the B +3 + He system, our calculations are in excellent agreement with experimental results with the finding that the single-electron-transfer cross section rises rapidly to a maximum of 1.45 x 10 -15 cm 2 at v = 5.5 x 10 7 cm/sec. For the C +4 + He system, however, we find that the double-electron-transfer process is more important than the single-electron-transfer process. For example, at v = 5 x 10 7 cm/sec, the double-electron-transfer cross section is found to be 0.6 x 10 -16 cm 2 vs 5.5 x 10 -17 for the single-electron transfer. This is in disagreement with an experiment of Crandall which gave the single-charge-transfer process as dominant. However, the more recent experiment reported by Crandall, Olson, Browne, and Shipsey verifies the double charge transfer as the dominant process for low energies

  20. Note on some charge exchange cross sections of inelastic pn and pp reactions in terms of the quark interchange concept

    International Nuclear Information System (INIS)

    Bakken, V.; Jacobsen, T.

    The charge exchange cross sections observed for pN interactions at 19 GeV/c in terms of the quark-quark interchange concept are discussed. If one uu-pair and one dd-pair of sea-quarks are assigned to each initial nucleon in pn and pp inelastic reactions, and if these quarks are assumed to participate on equal footing with the valence quarks in a quark-quark interchange mechanism between the two initial nucleons, the ratios between some observed charge exchange cross sections are well reproduced. This indicates that in this model the sea-quarks contribute significantly to the particle production in low p(subT) hadronic processes. (Auth.)

  1. Hidden crossing theory of charge exchange in H+ + He+(1 s) collisions in vicinity of maximum of cross section

    Science.gov (United States)

    Grozdanov, Tasko P.; Solov'ev, Evgeni A.

    2018-04-01

    Within the framework of dynamical adiabatic approach the hidden crossing theory of inelastic transitions is applied to charge exchange in H+ + He+(1 s) collisions in the wide range of center of mass collision energies E cm = (1.6 -70) keV. The good agreement with experiment and molecular close coupling calculations is obtained. At low energies our 4-state results are closest to the experiment and correctly reproduce the shoulder in energy dependence of the cross section around E cm = 6 keV. The 2-state results correctly predict the position of the maximum of the cross section at E cm ≈ 40 keV, whereas 4-state results fail to correctly describe the region around the maximum. The reason for this is the fact that adiabatic approximation for a given two-state hidden crossing is applicable for values of the Schtueckelberg parameter >1. But with increase of principal quantum number N the Schtueckelberg parameter decreases as N -3. That is why the 4-state approach involving higher excited states fails at smaller collision energies E cm ≈ 15 keV, while the 2-state approximation which involves low lying states can be extended to higher collision energies.

  2. Calculation of the cross section of the H2+(D2+)+Li→Li++2H(2D) charge-exchange reaction

    International Nuclear Information System (INIS)

    Voronin, A.I.; Osherov, V.I.; Poluyanov, L.V.; Ushakov, V.G.

    1983-01-01

    The method of classic trajectories with account for non-adiabatic transitions has been used to calculate Li atoms charge-exchange cross sections on H 2 + and D 2 + ions depending on collision energy and oscillatory excitation of molecular ion. Surfaces of potentil energy of nuclei interaction corresponding to essential for the chargeexchange process electron states are plotted by the diatomics-in-molecules (DIM) method. Qualitative characteristics of calculated cross sections (dependence on collision energy, oscillatory number, deuteration effect) coincide well with those obtained during the experiment. However the experimental cross section value approximately two times surpasses the theoretical one. This is connected with insufficient accuracy of the DIM method

  3. Electron capture cross sections by O+ from atomic He

    International Nuclear Information System (INIS)

    Joseph, Dwayne C; Saha, Bidhan C

    2009-01-01

    The adiabatic representation is used in both the quantal and semi classical molecular orbital close coupling methods (MOCC) to evaluate charge exchange cross sections. Our results show good agreement with experimental cross sections

  4. Electron capture cross sections by O+ from atomic He

    Science.gov (United States)

    Joseph, Dwayne C.; Saha, Bidhan C.

    2009-11-01

    The adiabatic representation is used in both the quantal and semi classical molecular orbital close coupling methods (MOCC) to evaluate charge exchange cross sections. Our results show good agreement with experimental cross sections

  5. Numerical investigation on the thermo-mechanical behavior of a quadratic cross section pile heat exchanger

    DEFF Research Database (Denmark)

    Alberdi Pagola, Maria; Madsen, Søren; Lund Jensen, Rasmus

    2017-01-01

    Pile heat exchangers are traditional foundation piles with built in heat exchangers. As such, the footing of the building both serves as a structural component and a heating/cooling supply element. The existing geotechnical design standards do not consider the nature of thermo-active foundations...... and, therefore, there is a need to develop guidelines to design them properly. This paper contributes by studying the thermo-mechanical behavior of the precast piles which are 15-meter long and have a quadratic cross section and a W-shape pipe heat exchanger. This article aims to numerically assess...... the additional changes in the pile load transfer generated by its heating and cooling. In addressing this objective, a preliminary multi-physical finite element analysis is conducted which serves as a tool for exploring: i) the thermally induced mechanical stresses within the concrete and on the pile-soil axial...

  6. High-energy behaviour of e--H scattering cross section

    International Nuclear Information System (INIS)

    Saha, B.C.; Chaudhuri, J.; Ghosh, A.S.

    1976-01-01

    An integral form of the close coupling equation has been employed to investigate the high energy behaviour of the elastic and 2s excitation cross sections of hydrogen atom by electron impact retaining the 1s and 2s states. The results, with and without exchange, for both the total and the differential cross sections are presented. The effects of exchange as well as of couplings to the 1s-2s states on the elastic cross section have been studied. The FBA results for the elastic cross section differ from the present results appreciably in the energy range 100 to 200 eV where FBA is considered to be valid. On the other hand, the present 1s-2s excitation results are very close to the corresponding FBA results in the said energy region. (auth.)

  7. Electron capture cross sections by O{sup +} from atomic He

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Dwayne C; Saha, Bidhan C [Department of Physics, Florida A and M University, Tallahassee, FL-32307 (United States)

    2009-11-01

    The adiabatic representation is used in both the quantal and semi classical molecular orbital close coupling methods (MOCC) to evaluate charge exchange cross sections. Our results show good agreement with experimental cross sections

  8. Prediction of e± elastic scattering cross-section ratio based on phenomenological two-photon exchange corrections

    Science.gov (United States)

    Qattan, I. A.

    2017-06-01

    I present a prediction of the e± elastic scattering cross-section ratio, Re+e-, as determined using a new parametrization of the two-photon exchange (TPE) corrections to electron-proton elastic scattering cross section σR. The extracted ratio is compared to several previous phenomenological extractions, TPE hadronic calculations, and direct measurements from the comparison of electron and positron scattering. The TPE corrections and the ratio Re+e- show a clear change of sign at low Q2, which is necessary to explain the high-Q2 form factors discrepancy while being consistent with the known Q2→0 limit. While my predictions are in generally good agreement with previous extractions, TPE hadronic calculations, and existing world data including the recent two measurements from the CLAS and VEPP-3 Novosibirsk experiments, they are larger than the new OLYMPUS measurements at larger Q2 values.

  9. Measurement and Calculation of Absolute Single- and Multiple-Charge-Exchange Cross Sections for Feq+ Ions Impacting CO and CO2

    Energy Technology Data Exchange (ETDEWEB)

    Simcic, J. [Jet Propulsion Laboratory/Caltech; Schultz, David Robert [ORNL; Mawhorter, R. J. [Pomona College; Cadez, I. [Jozef Stefan Institute, Slovenia; Greenwood, J. B. [Queen' s University, Belfast; Chutjian, A. [Jet Propulsion Laboratory/Caltech; Lisse, Carey M. [Johns Hopkins University; Smith, S. J. [Indiana Wesleyan University, Marion

    2010-01-01

    Absolute cross sections are reported for single, double, and triple charge exchange of Feq+ (q=5- 13) ions with CO and CO2. The highly-charged Fe ions are generated in an electron cyclotron resonance ion source. Absolute data are derived from knowledge of the target gas pressure, target path length, and incident and charge-exchanged ion currents. Experimental results are compared with new calculations of these cross sections in the n-electron classical trajectory Monte-Carlo approximation, in which the ensuing radiative and non-radiative cascades are approximated with scaled hydrogenic transition probabilities and scaled Auger rates. The present data are needed in astrophysical applications of solar- and stellar-wind charge-exchange with comets, planetary atmospheres, and circumstellar clouds.

  10. Charge changing collision cross sections of atomic ions

    International Nuclear Information System (INIS)

    Bliman, S.; Dousson, S.; Geller, R.; Jacquot, B.; Van Houtte, D.

    1980-05-01

    A device has been built to measure charge changing cross sections of atomic ions. It consists of an E.C.R. ion source (Micromafios) that delivers oxygen ions up to charge + 8, argon ions up to charge + 13. The ion source potential may be varied from 1 up to 10 kVolts. A first magnet is used to charge analyze the extracted beam. For a given charge state, the ion beam is passed in a collision cell whose pressure may be varied. The ions undergoing collisions on the target are analyzed by a second magnet and collected. The single collision condition is checked. Different collisions are considered: 1- Charge exchange collisions of argon ions with charge 2<=Z<=12 on argon. Cross sections for capture of 1, 2 and 3 electrons are given. 2- Stripping of argon ions (1<=Z<=4) on argon atoms. 3- Charge exchange of oxygen ions (2<=Z<=8) colliding on deuterium. One and two electron capture cross sections are presented

  11. Collision processes of Li3+ with atomic hydrogen: cross section database

    International Nuclear Information System (INIS)

    Murakami, I.; Janev, R.K.; Kato, T.; Yan, J.; Sato, H.; Kimura, M.

    2004-08-01

    Using the available experimental and theoretical data, as well as established cross section scaling relationships, a cross section database for excitation, ionization and charge exchange in collisions of Li 3+ ion with ground state and excited hydrogen atoms has been generated. The critically assessed cross sections are represented by analytic fit functions that have correct asymptotic behavior both at low and high collision energies. The derived cross sections are also presented in graphical form. (author)

  12. Baryon exchange in 12 GeV/c. pi. /sup -/p interactions. [Differential cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Arenton, M W; Bacino, W J; Hauptman, J M; Rudnick, F D; Shepard, P F; Slater, W E; Stork, D H; Ticho, H K [California Univ., Los Angeles (USA)

    1978-08-14

    Final states produced by charged baryon exchange in ..pi../sup -/p interactions at 12 GeV/c laboratory momentum have been studied. Forward neutrons with momenta determined by a calorimeter to be greater than 8.5 +- 1.4 GeV/c triggered the SLAC 40-inch hydrogen bubble chamber which operated at a 10 Hz expansion rate. Data on the reactions ..pi../sup -/p..-->..n..pi../sup -/..pi../sup +/, ..pi../sup -/p..-->..n..pi../sup -/..pi../sup +/..pi../sup 0/, and ..pi../sup -/p..-->..n..pi../sup -/..pi../sup -/..pi../sup +/..pi../sup +/are reported. In ..pi../sup -/p..-->..n..pi../sup -/..pi../sup +/ production of rho and f mesons is observed. Differential cross sections are derived and compared with data at lower incident momentum and with theoretical models. In ..pi../sup -/p..-->..n..pi../sup -/..pi../sup +/..pi../sup 0/, ..omega.. production is observed with a differential cross section having a deep dip near u' = 0.2 (GeV/c)/sup 2/. In ..pi../sup -/p..-->..n..pi../sup -/..pi../sup -/..pi../sup +/..pi../sup +/, ..delta../sup -/, rho and f production is observed. The observed mass distributions appear to indicate the production of wide resonances decaying into rho..pi pi... Some evidence for rho-..omega.. interference is also observed.

  13. Program ECSX4 (version 78-1): conversion of experimentally measured cross-section data from the four-center-exchange (X-4) format to the Livermore ECSIL format

    International Nuclear Information System (INIS)

    Cullen, D.E.; Perkins, S.T.

    1978-01-01

    A computer code called ECSX4 converts experimentally measured cross-section data from the four-center-exchange (X-4) format to the Livermore Experimental Cross-Section Information Library (ECSIL) format. The major advantage of this program is that it converts the variable format and dimensioned data of the X-4 format to the fixed-field format and consistent set of units of the ECSIL format. This consistency greatly simplifies the subsequent use of the data for cross-section evaluations. 2 figures, 3 tables

  14. 1st IAEA research co-ordination meeting on charge exchange cross section data for fusion plasma studies. Summary report

    International Nuclear Information System (INIS)

    Janev, R.K.

    1999-02-01

    A brief description of the proceedings and the conclusions of the 1st Research Coordination Meeting on 'Charge Exchange Cross Section Data for Fusion Plasma Studies', held on September 24-25, 1999, at the IAEA Headquarters in Vienna, Austria, is provided. The conclusions of the Meeting regarding the data collection, assessment and generation priorities are also included in the report. (author)

  15. Double Regge pole exchange model analysis of a 7 Gev/c. pi. /sup -/p experiment. [Absolute cross sections, one-particle exchange, diffraction scattering

    Energy Technology Data Exchange (ETDEWEB)

    Chao, A C.L.

    1973-01-01

    A double Regge Pole Exchange Model is used to analyze Quasi-Three-Body final states selected from a 7 GeV/c - /sup -/p experiment. Three sets of data are analyzed namely: I ..pi../sup -/p ..-->.. p..pi../sup +/..pi../sup -/..pi../sup -/; II ..pi../sup -/p ..-->.. p..pi../sup +/..pi../sup -/..pi../sup -/..pi../sup 0/; III ..pi../sup -/p ..-->.. ..pi../sup +/..pi../sup +/..pi../sup -/..pi../sup -/n. The final states, selected from data sets I, II and III are (rho/sup 0/..pi../sup -/p, f/sup 0/..pi../sup -/p, ..pi../sup -/..pi../sup -/..delta../sup + +/), (rho/sup 0/..pi../sup -/..delta../sup +/, rho/sup -/..pi..-..delta../sup + +/, ..omega pi../sup -/p) and (rho/sup 0/..pi../sup -/..delta../sup +/), respectively. It is found that these channels after appropriate kinematic cuts can be well described by exchanging two Regge Trajectories. Predictions for the absolute cross-sections were also obtained by taking limits of one particle exchange and a diffraction scattering approximation. (auth)

  16. Measurement of Antiproton-proton Cross-Sections at Low Antiproton Momenta

    CERN Multimedia

    2002-01-01

    The experiment is designed to measure four different cross sections in the momentum range 150~MeV/c to 600~MeV/c: 1)~~~~the differential elastic \\\\ \\\\ 2)~~~~the differential charge exchange\\\\ \\\\ 3)~~~~the annihilation into charged and neutral pions\\\\ \\\\ 4)~~~~and the total cross section via the optical theorem. \\\\ \\\\ The experiment allows one to search once again and with good precision for baryonium. Of special interest is the existence of the S-meson, for which a signal of about 20~MeV-mb was found in a 1981 experiment (performed in the East Hall).\\\\ \\\\ A second point of special interest is the momentum region below 300~MeV/c because the cross sections are basically unknown. We will be able to explore the momentum dependence of this region for the first time.\\\\ \\\\ The elastic cross section is measured by a cylindrical multiwire proportional chamber and a scintillator hodoscope placed around a scattering chamber under vacuum. The charge exchange cross section is measured by a ring of 32~anti-neutron detector...

  17. Negative ion detachment cross sections

    International Nuclear Information System (INIS)

    Champion, R.L.; Doverspike, L.D.

    1992-10-01

    The authors have measured absolute cross sections for electron detachment and charge exchange for collision of O and S with atomic hydrogen, have investigated the sputtering and photodesorption of negative ions from gas covered surfaces, and have begun an investigation of photon-induced field emission of electrons from exotic structures. Brief descriptions of these activities as well as future plans for these projects are given below

  18. Approximate method of calculation of non-equilibrium flow parameters of chemically reacting nitrogen tetroxide in the variable cross-section channels with energy exchange

    International Nuclear Information System (INIS)

    Bazhin, M.A.; Fedosenko, G.Eh.; Shiryaeva, N.M.; Mal'ko, M.V.

    1986-01-01

    It is shown that adiabatic non-equilibrium chemically reacting gas flow with energy exchange in a variable cross-section channel may be subdivided into five possible types: 1) quasi-equilibrium flow; 2) flow in the linear region of deviation from equilibrium state; 3) quasi-frozen flow; 4) flow in the linear region of deviation from frozen state; 5) non-equilibrium flow. Criteria of quasi-equilibrium and quazi-frozen flows, including factors of external action of chemically reacting gas on flow, allow to obtain simple but sufficiently reliable approximate method of calculation of flow parameters. The considered method for solving the problem of chemically reacting nitrogen tetroxide in the variable cross-section channel with energy exchange can be used for evaluation of chemical reaction kinetics on the flow parameter in the stages of axial-flow and radial-flow turbines and in another practical problems

  19. Absolute cross-section measurements of inner-shell ionization

    Science.gov (United States)

    Schneider, Hans; Tobehn, Ingo; Ebel, Frank; Hippler, Rainer

    1994-12-01

    Cross section ratios for K- and L-shell ionization of thin silver and gold targets by positron and electron impact have been determined at projectile energies of 30 70 keV. The experimental results are confirmed by calculations in plane wave Born approximation (PWBA) which include an electron exchange term and account for the deceleration or acceleration of the incident projectile in the nuclear field of the target atom. We report first absolute cross sections for K- and L-shell ionization of silver and gold targets by lepton impact in the threshold region. We have measured the corresponding cross sections for electron (e-) impact with an electron gun and the same experimental set-up.

  20. Elastic neutron-proton differential cross section at 647 MeV

    International Nuclear Information System (INIS)

    Evans, M.L.

    1979-04-01

    The differential cross section for n-p elastic scattering in the angular range 51 0 was measured with high statistical accuracy using the 647 MeV monoenergetic neutron beam of the Los Alamos Meson Physics Facility. A proton recoil magnetic spectrometer was used for momentum analysis of the charge exchange protons from the reaction n+p→p+n. Absolute normalization of the cross section was established to within 7% using existing cross section data for the reaction p+p→π + +d. The results differ significantly from previous Dubna and PPA cross sections but agree well with recent Saclay data except at extreme backward angles. 41 references

  1. Towards extraction of {pi}{sup +}p and {pi}{sup +}{pi}{sup +} cross-sections from charge exchange processes at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Ryutin, R.A.; Petrov, V.A.; Sobol, A.E. [Institute for High Energy Physics, Protvino (Russian Federation)

    2011-05-15

    We study the possibilities to analyse the data on leading neutrons production at first LHC runs. These data could be used to extract from it {pi}{sup +}p and {pi}{sup +}{pi}{sup +} cross-sections. In this note we estimate relative contributions of {pi}, {rho} and a{sub 2} reggeons to charge exchanges and discuss related problems of measurements. (orig.)

  2. Absolute cross sections from the ''boomerang model'' for resonant electron-molecule scattering

    International Nuclear Information System (INIS)

    Dube, L.; Herzenberg, A.

    1979-01-01

    The boomerang model is used to calculate absolute cross sections near the 2 Pi/sub g/ shape resonance in e-N 2 scattering. The calculated cross sections are shown to satisfy detailed balancing. The exchange of electrons is taken into account. A parametrized complex-potential curve for the intermediate N 2 /sup ts-/ ion is determined from a small part of the experimental data, and then used to calculate other properties. The calculations are in good agreement with the absolute cross sections for vibrational excitation from the ground state, the absolute cross section v = 1 → 2, and the absolute total cross section

  3. Electron-impact-excitation cross sections of hydrogenlike ions

    International Nuclear Information System (INIS)

    Fisher, V.I.; Ralchenko, Y.V.; Bernshtam, V.A.; Goldgirsh, A.; Maron, Y.; Vainshtein, L.A.; Bray, I.; Golten, H.

    1997-01-01

    Convergent close-coupling (CCC) and Coulomb-Born with exchange and normalization (CBE) methods are used to study electron-impact excitation of hydrogenlike ions. The nl→n ' l ' cross sections demonstrate (i) good agreement between the CCC and CBE results, (ii) a scaling over ion nuclear charge z, (iii) a domination of the dipole (l ' =l±1) contributions in total n→n ' cross sections, and (iv) significant effect of electron exchange in the energy range x n,n ' ). For ions with z>5 the n→n ' cross sections obtained in the CCC and CBE approximations agree with each other to better than 10% for any x. An accuracy of the cross sections scaling over z 4 depends on z: for z=6 endash 18 the scaling is accurate to better than 10% (quantitative analysis is done for n ' 4 scaling more significantly (at x about unity). The n→n ' cross sections are presented by a formula which fits our CCC and CBE results with an accuracy to better than 10% (for transitions with n ' 5). The new Gaunt factor G(x) suggested for the widely used Van Regemorter formula [Astrophys. J. 136, 906 (1962)] makes this formula accurate to better than 50% in the x>3 range and to better than 20% in the x>100 range. It is shown that the semiempirical formula by Vainshtein, Sobelman, and Yukov provides an accuracy to better than 50% for any incident electron energy. For x<2 this formula is accurate to better than 30%. These accuracy assessments are based on a comparison with our CCC and CBE results. copyright 1997 The American Physical Society

  4. Measurement of the $\\bar{p}p \\rightarrow \\bar{n}n$ Charge-Exchange Differential Cross-Section

    CERN Multimedia

    2002-01-01

    The aim of this proposal is a measurement of the differential cross-section of the $\\bar{p}$p $\\rightarrow$ $\\bar{n}$n charge-exchange reaction with a point-to-point precision of 1\\% in the forward direction, and an absolute normalization error of 3\\%. The high precision of the data should allow, inter alia, a determination of the $\\pi$NN coupling constant to better than 2\\%.\\\\ \\\\ The measurement will be done using the existing neutron and antineutron detectors built for experiment PS199 and liquid hydrogen target. In one week of running time, with a $\\bar{p}$ beam intensity of 3 $ 10 ^{5} $ $\\bar{p}$/sec, the reaction will be measured at a few $\\bar{p}$ momenta, in the range 500 to 900~MeV/c.

  5. single-top quark production cross section using the ATLAS detector

    CERN Document Server

    Feng, Cunfeng; The ATLAS collaboration

    2014-01-01

    Measurements of single top-quark production cross section in proton proton collisions at 7 and 8 TeV are presented. In the leading order process, a W boson is exchanged in the t-channel. For this process, for the first time a fiducial cross section measured within the detector acceptance is presented and the modelling uncertainty when extrapolating to the total inclusive cross section is assessed with a large number of different Monte Carlo generators. The result is in good agreement with the most up-to-date theory predictions. Furthermore, the single top-quark and anti-top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. Differential cross sections are measured as a function of the transverse momentum and the absolute value of the rapidity of top and anti-top quarks. In addition, a measurement of the production cross section of a single top quark in association with a W boson is presented. The s-channel production is explored and l...

  6. The γ* p total cross section at low x

    International Nuclear Information System (INIS)

    Schildknecht, D.

    2001-01-01

    We have shown that the HERA data on DIS in the low-x diffraction region, including Q 2 = 0 photoproduction, find a natural interpretation in the GVD/CDP that rests on the generic structure of two-gluon exchange from QCD. The gluon density that in the appropriate limit corresponds to the color-dipole cross section is consistent with the results from QCD fits. The cross sections for real and virtual photons on protons become identical in the limit of infinite energy

  7. γ*γ* total cross section in the dipole picture of BFKL dynamics

    International Nuclear Information System (INIS)

    Boonekamp, Maarten; De Roeck, Albert; Royon, Christophe; Wallon, Samuel

    1999-01-01

    The total γ * γ * cross section is derived in the leading order QCD dipole picture of BFKL dynamics, and compared with the one from two-gluon exchange. The double leading logarithm approximation of the DGLAP cross section is found to be small in the phase space studied. Cross sections are calculated for realistic data samples at the e + e - collider LEP and a future high energy linear collider. Next to leading order corrections to the BFKL evolution have been determined phenomenologically, and are found to give very large corrections to the BFKL cross section, leading to a reduced sensitivity for observing BFKL effects

  8. γ*γ* total cross-section in the dipole picture of BFKL dynamics

    International Nuclear Information System (INIS)

    Boonekamp, M.; Royon, C.; Wallon, S.; Universite Pierre et Marie Curie, 75 - Paris

    1999-01-01

    The total γ * γ * cross-section is derived in the Leading Order QCD dipole picture of BFKL dynamics, and compared with the one from 2-gluon exchange. The Double Leading Logarithm approximation of the DGLAP cross-section is found to be small in the phase space studied. Cross sections are calculated for realistic data samples at the e + e - collider LEP and a future high energy linear collider. Next to Leading order corrections to the BFKL evolution have been determined phenomenologically, and are found to give very large corrections to the BFKL cross-section, leading to a reduced sensitivity for observing BFKL. (author)

  9. $\\gamma^{*}\\gamma^{*}$ total cross-section in the dipole picture of BFKL dynamics

    CERN Document Server

    Boonekamp, M; Royon, C; Wallon, S

    1999-01-01

    The total $\\gamma^*\\gamma^*$ cross-section is derived in the Leading Order QCD dipole picture of BFKL dynamics, and compared with the one from 2-gluon exchange. The Double Leading Logarithm approximation of the DGLAP cross-section is found to be small in the phase space studied. Cross sections are calculated for realistic data samples at the $e^+e^-$ collider LEP and a future high energy linear collider. Next to Leading order corrections to the BFKL evolution have been determined phenomenologically, and are found to give very large corrections to the BFKL cross-section, leading to a reduced sensitivity for observing BFKL.

  10. Colour intransparency and the cross sections for colour-singlet and colour-octet hadrons in the Low-Nussinov model

    International Nuclear Information System (INIS)

    Dolejsi, J.; Huefner, J.

    1992-01-01

    The dependence of cross sections on the colour state of the colliding hadrons is investigated within the Low-Nussinov model of two-gluon exchange. The total cross sections for colour-octet hadrons are practically constant as functions of the hadronic radii, while they tend to zero when the radii of the colour-singlet hadrons approach zero. The slope parameter of the differential elastic cross sections for small momentum transfers is rather insensitive to the colour structure of the colliding hadrons. The integrated colour exchange cross section is calculated. (orig.)

  11. Total cross sections for pion charge exchange on the proton

    International Nuclear Information System (INIS)

    Breitschopf, J.

    2006-01-01

    This work describes the measurement of total SCX cross sections employing a new 4π scintillation counter to perform transmission measurements in the incident pion energy range from about 38 to 250 MeV. A small 4π detector box consisting of thin plastic scintillators has been constructed. The transmission technique, which was used, relates the number of transmitted charged pions to that of incident beam pions and this way effectively counts events with neutral products. The incoming negative pions were counted by three beam defining counters before they hit a target of very well known size and chemical composition. The target was placed in the box detector which was not sensitive to the neutral particles resulting from the SCX. The total cross section for emerging neutral particles was derived from the comparison of the numbers of the incoming and transmitted charged particles. The total SCX cross section on hydrogen was derived from the transmissions of a CH 2 target, a carbon target and an empty target. For a detailed offline analysis all TDC, QDC and FADC information was recorded in an event by event mode for each triggered beam event. Various corrections had to be applied to the data, such as random correction, the detection of neutrals in the detector, Dalitz decay, pion decay and the radiative pion capture. This measurement covers, as the only experiment, the whole Δ-resonance and the sp-interference region in one single experimental setup and improves the available data base for the SCX reaction. It is shown that the description of the SCX cross sections is improved if the s-wave amplitudes, that have been fixed essentially by elastic pion-nucleon scattering data, is reduced by (4±1.5)%. The exact value depends on the SCX literature data included and on the parameters of the Δ 0 Breit-Wigner resonance describing the p 33 -waves. This shows that p-wave as well as s-wave effects should be considered in studies of isospin symmetry breaking. Interestingly

  12. Total cross sections for pion charge exchange on the proton

    Energy Technology Data Exchange (ETDEWEB)

    Breitschopf, J.

    2006-04-28

    This work describes the measurement of total SCX cross sections employing a new 4{pi} scintillation counter to perform transmission measurements in the incident pion energy range from about 38 to 250 MeV. A small 4{pi} detector box consisting of thin plastic scintillators has been constructed. The transmission technique, which was used, relates the number of transmitted charged pions to that of incident beam pions and this way effectively counts events with neutral products. The incoming negative pions were counted by three beam defining counters before they hit a target of very well known size and chemical composition. The target was placed in the box detector which was not sensitive to the neutral particles resulting from the SCX. The total cross section for emerging neutral particles was derived from the comparison of the numbers of the incoming and transmitted charged particles. The total SCX cross section on hydrogen was derived from the transmissions of a CH{sub 2} target, a carbon target and an empty target. For a detailed offline analysis all TDC, QDC and FADC information was recorded in an event by event mode for each triggered beam event. Various corrections had to be applied to the data, such as random correction, the detection of neutrals in the detector, Dalitz decay, pion decay and the radiative pion capture. This measurement covers, as the only experiment, the whole {delta}-resonance and the sp-interference region in one single experimental setup and improves the available data base for the SCX reaction. It is shown that the description of the SCX cross sections is improved if the s-wave amplitudes, that have been fixed essentially by elastic pion-nucleon scattering data, is reduced by (4{+-}1.5)%. The exact value depends on the SCX literature data included and on the parameters of the {delta}{sup 0} Breit-Wigner resonance describing the p{sub 33}-waves. This shows that p-wave as well as s-wave effects should be considered in studies of isospin

  13. Cross sections of electron excitation out of metastable helium levels with a fast metastable target product produced via charge exchange

    International Nuclear Information System (INIS)

    Lagus, M.E.; Boffard, J.B.; Anderson, L.W.; Lin, C.C.

    1996-01-01

    Absolute direct cross sections for electron excitation out of the 2 3 S level and into the 3 3 D, 4 3 D, and 3 3 S levels of the helium atom from threshold to 500 eV and into the 3 3 P level over a more limited energy range have been measured using a fast metastable atomic beam target. We produce the metastable atoms via near-resonant charge exchange between a 1.6-keV He + ion beam and Cs vapor. Because this reaction is highly nonresonant with the ground state of helium, the charge-transfer process yields a primarily metastable beam. We use a thermal detector which we calibrate with ions to measure absolutely the neutral beam flux. The atomic beam is crossed by an electron beam, and we collect the resulting fluorescence at right angles to both the electron and atomic beams. We obtain the cross sections for excitation out of the 2 3 S level into the various excited levels by monitoring the emission out of the excited level of interest. copyright 1996 The American Physical Society

  14. Differential bremsstrahlung and pair production cross sections at high energies

    International Nuclear Information System (INIS)

    Olsen, Haakon A.

    2003-01-01

    Detailed differential cross sections for high energy bremsstrahlung and pair production are derived with specific attention to the differences between the two processes, which are considerable. For the integrated cross sections, which are the only cross sections specifically known until now, the final state integration theorem guarantees that the exact cross section formulas can be exchanged between bremsstrahlung and pair production by the same substitution rules as for the Born-approximation Bethe-Heitler cross sections, for any amount of atomic screening. In fact the theorem states that the Coulomb corrections to the integrated bremsstrahlung and pair production cross sections are identical for any amount of screening. The analysis of the basic differential cross sections leads to fundamental physical differences between bremsstrahlung and pair production. Coulomb corrections occur for pair production in the strong electric field of the atom for 'large' momentum transfer of the order of mc. For bremsstrahlung, on the other hand, the Coulomb corrections take place at a 'large' distance from the atom of the order of ((ℎ/2π)/mc)ε, with a 'small' momentum transfer mc/ε, where ε is the initial electron energy in units of mc 2 . And the Coulomb corrections can be large, of the order of larger than (Z/137) 2 , which is considerably larger than the integrated cross section corrections

  15. Cross sections for multistep direct reactions

    International Nuclear Information System (INIS)

    Demetriou, Paraskevi; Marcinkowski, Andrzej; Marianski, Bohdan

    2002-01-01

    Inelastic scattering and charge-exchange reactions have been analysed at energies ranging from 14 to 27 MeV using the modified multistep direct reaction theory (MSD) of Feshbach, Kerman and Koonin. The modified theory considers the non-DWBA matrix elements in the MSD cross section formulae and includes both incoherent particle-hole excitations and coherent collective excitations in the continuum, according to the prescriptions. The results show important contributions from multistep processes at all energies considered. (author)

  16. 2nd (final) IAEA research co-ordination meeting on 'charge exchange cross section data for fusion plasma studies'. Summary report

    International Nuclear Information System (INIS)

    Clark, R.E.H.

    2001-11-01

    The proceedings and conclusions of the 2nd Research Co-ordination Meeting on 'Charge Exchange Cross Section Data for Fusion Plasma Studies', held on September 25 and 26, 2000 at the IAEA Headquarters in Vienna, are briefly described. This report includes a summary of the presentations made by the meeting participants and a review of the accomplishments of the Co-ordinated Research Project (CRP). In addition, short summaries from the participants are included indicating the specific research completed in support of this CRP. (author)

  17. Single Top quark production cross section using the ATLAS detector at the LHC

    CERN Document Server

    Hirschbuehl, D; The ATLAS collaboration

    2014-01-01

    Measurements of single top-quark production cross section in proton proton collisions at 7 and 8 TeV are presented. In the leading order process, a W boson is exchanged in the t-channel. For this process for the first time a fiducial cross section measured within the detector acceptance is presented and the modelling uncertainty when extrapolating to the total inclusive cross section is assessed with a large number of different Monte Carlo generators. The result is in good agreement with the most up-to-date theory predictions. Furthermore, the single top-quark and anti-top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. Differential cross sections are measured as a function of the transverse momentum and the absolute value of the rapidity of top and anti-top quarks.

  18. Electron impact ionization of B-like ion N2+. Resonance enhancement of the single-channel cross section

    International Nuclear Information System (INIS)

    Li Guohe; Qian Xingzhong; Pan Soufu

    1998-01-01

    The electron impact ionization cross sections of B-like ion N 2+ are calculated in the Coulomb-Born no exchange approximation by using R-matrix method, and the single differential cross section is given. The calculated results exhibit the Rydberg series of resonances. The resonance enhancement of the single-channel cross section is significantly greater than direct ionization cross section. It is agreement with that of Chidichimo

  19. Recent measurements of low energy charge exchange cross sections for collisions of multicharged ions on neutral atoms and molecules

    International Nuclear Information System (INIS)

    Havener, Charles C.

    2001-01-01

    At ORNL Multicharged Ion Research Facility (MIRF), charge exchange (CX) cross sections have been measured for multicharged ions (MCI) on neutral atoms and molecules. The ORNL ion-atom merged-beam apparatus was used to measure single electron capture by MCI from H at eV/amu energies. A gas cell was used to measure single and double electron capture by MCI from a variety of molecular targets at keV collision energies. The merged-beams experiment has been successful in providing benchmark total electron capture measurements for several collision systems with a variety of multicharged ions on H or D

  20. Effectiveness-ntu computation with a mathematical model for cross-flow heat exchangers

    Directory of Open Access Journals (Sweden)

    H. A. Navarro

    2007-12-01

    Full Text Available Due to the wide range of design possibilities, simple manufactured, low maintenance and low cost, cross-flow heat exchangers are extensively used in the petroleum, petrochemical, air conditioning, food storage, and others industries. In this paper a mathematical model for cross-flow heat exchangers with complex flow arrangements for determining epsilon -NTU relations is presented. The model is based on the tube element approach, according to which the heat exchanger outlet temperatures are obtained by discretizing the coil along the tube fluid path. In each cross section of the element, tube-side fluid temperature is assumed to be constant because the heat capacity rate ratio C*=Cmin/Cmax tends toward zero in the element. Thus temperature is controlled by effectiveness of a local element corresponding to an evaporator or a condenser-type element. The model is validated through comparison with theoretical algebraic relations for single-pass cross-flow arrangements with one or more rows. Very small relative errors are obtained showing the accuracy of the present model. epsilon -NTU curves for several complex circuit arrangements are presented. The model developed represents a useful research tool for theoretical and experimental studies on heat exchangers performance.

  1. Status of Charge Exchange Cross Section Measurements for Highly Charged Ions on Atomic Hydrogen

    Science.gov (United States)

    Draganic, I. N.; Havener, C. C.; Schultz, D. R.; Seely, D. G.; Schultz, P. C.

    2011-05-01

    Total cross sections of charge exchange (CX) for C5+, N6+, and O7+ ions on ground state atomic hydrogen are measured in an extended collision energy range of 1 - 20,000 eV/u. Absolute CX measurements are performed using an improved merged-beams technique with intense highly charged ion beams extracted from a 14.5 GHz ECR ion source mounted on a high voltage platform. In order to improve the problematic H+ signal collection for these exoergic CX collisions at low relative energies, a new double focusing electrostatic analyzer was installed. Experimental CX data are in good agreement with all previous H-oven relative measurements at higher collision energies. We compare our results with the most recent molecular orbital close-coupling (MOCC) and atomic orbital close-coupling (AOCC) theoretical calculations. Work supported by the NASA Solar & Heliospheric Physics Program NNH07ZDA001N, the Office of Fusion Energy Sciences and the Division of Chemical Sciences, Geosciences, and Biosciences, and the Office of Basic Energy Sciences of the U.S. DoE.

  2. Photodetachment cross sections for He-(4P0)

    International Nuclear Information System (INIS)

    Compton, R.N.; Alton, G.D.; Pegg, D.J.

    1980-01-01

    The first measurements are reported of photodetachment cross sections for He - (formed through charge exchange of He + with Ca vapor) over the photon energy range from 1.77 to 2.75 eV. The energies of autodetached electrons from the metastable He - beam have also been determined for the first time. The autodetached electron energy agrees within experimental error (+-0.25 eV) with the known 1s2s2p) 4 P 0 He - energy level. This taken with measurements for the lifetime of He - infers that charge exchange of He + with Ca vapor produces 4 P 0 He -

  3. The momentum transfer cross section and transport coefficients for low energy electrons in mercury

    International Nuclear Information System (INIS)

    McEachran, R P; Elford, M T

    2003-01-01

    The momentum transfer cross section for electrons incident on mercury atoms has been determined from the solution of Dirac-Fock scattering equations which included both static and dynamic multipole polarization potentials as well as full anti-symmetrization to incorporate exchange effects. This cross section is in excellent agreement between 0.2 and 3.0 eV with the cross section derived from the most recent experimental measurements. The discrepancy below 0.2 eV has been investigated using two-term transport theory

  4. Cross-sample entropy of foreign exchange time series

    Science.gov (United States)

    Liu, Li-Zhi; Qian, Xi-Yuan; Lu, Heng-Yao

    2010-11-01

    The correlation of foreign exchange rates in currency markets is investigated based on the empirical data of DKK/USD, NOK/USD, CAD/USD, JPY/USD, KRW/USD, SGD/USD, THB/USD and TWD/USD for a period from 1995 to 2002. Cross-SampEn (cross-sample entropy) method is used to compare the returns of every two exchange rate time series to assess their degree of asynchrony. The calculation method of confidence interval of SampEn is extended and applied to cross-SampEn. The cross-SampEn and its confidence interval for every two of the exchange rate time series in periods 1995-1998 (before the Asian currency crisis) and 1999-2002 (after the Asian currency crisis) are calculated. The results show that the cross-SampEn of every two of these exchange rates becomes higher after the Asian currency crisis, indicating a higher asynchrony between the exchange rates. Especially for Singapore, Thailand and Taiwan, the cross-SampEn values after the Asian currency crisis are significantly higher than those before the Asian currency crisis. Comparison with the correlation coefficient shows that cross-SampEn is superior to describe the correlation between time series.

  5. Investigation of magnon dispersion relations and neutron scattering cross sections with special attention to anisotropy effects

    DEFF Research Database (Denmark)

    Lindgård, Per-Anker; Kowalska, A.; Laut, Peter

    1967-01-01

    curves are suggested. The magnon cross section for unpolarized neutrons is calculated and shown to be dependent on the anisotropy in the spin interaction. Thus in principle it allows the detection of anisotropy in the exchange interaction. Some remarks are made concerning antiferromagnetic and plane...... for the exchange interaction seem to be necessary for agreement with experimental dispersion curves be obtained. The effect of the anisotropy in the cross section is estimated and shown to be important for small magnon energies....

  6. Thermal conduction by dark matter with velocity and momentum-dependent cross-sections

    OpenAIRE

    Vincent, Aaron C.; Scott, Pat

    2013-01-01

    We use the formalism of Gould and Raffelt to compute the dimensionless thermal conduction coefficients for scattering of dark matter particles with standard model nucleons via cross-sections that depend on the relative velocity or momentum exchanged between particles. Motivated by models invoked to reconcile various recent results in direct detection, we explicitly compute the conduction coefficients $\\alpha$ and $\\kappa$ for cross-sections that go as $v_{\\rm rel}^2$, $v_{\\rm rel}^4$, $v_{\\rm...

  7. Uncertainties of Electron Capture Cross Sections In Be4+ + H(1s) Collisions

    International Nuclear Information System (INIS)

    Méndez, L.; Illescas, Clara; Jorge, Alba; Errea, L.F.; Rabadán, I.; Suárez, J.

    2014-01-01

    We have considered one-electron systems where the theoretical methods are well established. The use of different computational alternatives enables the accurate evaluation of nl-partial cross sections in a wide range of collision energies. In the presentation we have analyzed the uncertainties of n-partial charge exchange (CX) cross sections in Be 4+ + H(1s) collisions, which are relevant in tokamak plasmas and experimental data are not available.

  8. Neutron-photon multigroup cross sections for neutron energies up to 400 MeV: HILO86R

    International Nuclear Information System (INIS)

    Kotegawa, Hiroshi; Nakane, Yoshihiro; Hasegawa, Akira; Tanaka, Shun-ichi

    1993-02-01

    A macroscopic multigroup cross section library of 66 neutron and 22 photon groups for neutron energies up to 400 MeV: HILO86R is prepared for 10 typical shielding materials; water, concrete, iron, air, graphite, polyethylene, heavy concrete, lead, aluminum and soil. The library is a revision of the DLC-119/HILO86, in which only the cross sections below 19.6 MeV have been exchanged with a group cross section processed from the JENDL-3 microscopic cross section library. In the HILO86R library, self shielding factors are used to produce effective cross sections for neutrons less than 19.6 MeV considering rather coarse energy meshes. Energy spectra and dose attenuation in water, concrete and iron have been compared among the HILO, HILO86 and HILO86R libraries for different energy neutron sources. Significant discrepancy has been observed in the energy spectra less than a couple of MeV energy in iron among the libraries, resulting large difference in the dose attenuation. The difference was attributed to the effect of self-shielding factor, namely to the difference between infinite dilution and effective cross sections. Even for 400 MeV neutron source the influence of the self-shielding factor is significant, nevertheless only the cross sections below 19.6 MeV are exchanged. (author)

  9. Improved adiabatic calculation of muonic-hydrogen-atom cross sections. I. Isotopic exchange and elastic scattering in asymmetric collisions

    International Nuclear Information System (INIS)

    Cohen, J.S.; Struensee, M.C.

    1991-01-01

    The improved adiabatic representation is used in calculations of elastic and isotopic-exchange cross sections for asymmetric collisions of pμ, dμ, and tμ with bare p, d, and t nuclei and with H, D, and T atoms. This formulation dissociates properly, correcting a well-known deficiency of the standard adiabatic method for muonic-atom collisions, and includes some effects at zeroth order that are normally considered nonadiabatic. The electronic screening is calculated directly and precisely within the improved adiabatic description; it is found to be about 30% smaller in magnitude than the previously used value at large internuclear distances and to deviate considerably from the asymptotic form at small distances. The reactance matrices, needed for calculations of molecular-target effects, are given in tables

  10. Theoretical and experimental study on electron interactions with chlorobenzene: Shape resonances and differential cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Alessandra Souza [Departamento de Física, Universidade Federal do Paraná, CP 19044, 81531-990 Curitiba, Paraná (Brazil); Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Varella, Márcio T. do N. [Instituto de Física, Universidade de São Paulo, Rua do Matão 1731, 05508-090 São Paulo, SP (Brazil); Sanchez, Sergio d’A.; Bettega, Márcio H. F., E-mail: bettega@fisica.ufpr.br [Departamento de Física, Universidade Federal do Paraná, CP 19044, 81531-990 Curitiba, Paraná (Brazil); Ameixa, João; Limão-Vieira, Paulo; Ferreira da Silva, Filipe [Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Blanco, Francisco [Departamento de Física Atómica, Molecular y Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain); and others

    2016-08-28

    In this work, we report theoretical and experimental cross sections for elastic scattering of electrons by chlorobenzene (ClB). The theoretical integral and differential cross sections (DCSs) were obtained with the Schwinger multichannel method implemented with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR). The calculations with the SMCPP method were done in the static-exchange (SE) approximation, for energies above 12 eV, and in the static-exchange plus polarization approximation, for energies up to 12 eV. The calculations with the IAM-SCAR method covered energies up to 500 eV. The experimental differential cross sections were obtained in the high resolution electron energy loss spectrometer VG-SEELS 400, in Lisbon, for electron energies from 8.0 eV to 50 eV and angular range from 7{sup ∘} to 110{sup ∘}. From the present theoretical integral cross section (ICS) we discuss the low-energy shape-resonances present in chlorobenzene and compare our computed resonance spectra with available electron transmission spectroscopy data present in the literature. Since there is no other work in the literature reporting differential cross sections for this molecule, we compare our theoretical and experimental DCSs with experimental data available for the parent molecule benzene.

  11. Charge exchange cross sections in slow collisions of Si3+ with Hydrogen atom

    Science.gov (United States)

    Joseph, Dwayne; Quashie, Edwin; Saha, Bidhan

    2011-05-01

    In recent years both the experimental and theoretical studies of electron transfer in ion-atom collisions have progressed considerably. Accurate determination of the cross sections and an understanding of the dynamics of the electron-capture process by multiply charged ions from atomic hydrogen over a wide range of projectile velocities are important in various field ranging from fusion plasma to astrophysics. The soft X-ray emission from comets has been explained by charge transfer of solar wind ions, among them Si3+, with neutrals in the cometary gas vapor. The cross sections are evaluated using the (a) full quantum and (b) semi-classical molecular orbital close coupling (MOCC) methods. Adiabatic potentials and wave functions for relavent singlet and triplet states are generated using the MRDCI structure codes. Details will be presented at the conference. In recent years both the experimental and theoretical studies of electron transfer in ion-atom collisions have progressed considerably. Accurate determination of the cross sections and an understanding of the dynamics of the electron-capture process by multiply charged ions from atomic hydrogen over a wide range of projectile velocities are important in various field ranging from fusion plasma to astrophysics. The soft X-ray emission from comets has been explained by charge transfer of solar wind ions, among them Si3+, with neutrals in the cometary gas vapor. The cross sections are evaluated using the (a) full quantum and (b) semi-classical molecular orbital close coupling (MOCC) methods. Adiabatic potentials and wave functions for relavent singlet and triplet states are generated using the MRDCI structure codes. Details will be presented at the conference. Work supported by NSF CREST project (grant #0630370).

  12. Differential cross sections for the one electron two center symmetric systems

    International Nuclear Information System (INIS)

    Maidagan, J.M.; Piacentini, R.D.; Rivarola, R.D.; Universidad Autonoma de Madrid

    1982-01-01

    We use the two-state atomic expansion with variable nuclear charge to study charge-exchange differential cross sections for symmetrical one-electron systems at intermediate energy. The nonclassical small angle diffraction scattering is discussed. Our results are compared with data for H + -H collisions. (orig.)

  13. Differential cross sections for the one electron two center symmetric systems

    Energy Technology Data Exchange (ETDEWEB)

    Maidagan, J.M.; Piacentini, R.D. (Universidad Nacional de Rosario (Argentina). Dept. de Fisica); Rivarola, R.D. (Bordeaux-1 Univ., 33 - Talence (France). Lab. d' Astrophysique; Universidad Autonoma de Madrid (Spain). Dept. de Quimica Fisica y Quimica Cuantica)

    1982-03-01

    We use the two-state atomic expansion with variable nuclear charge to study charge-exchange differential cross sections for symmetrical one-electron systems at intermediate energy. The nonclassical small angle diffraction scattering is discussed. Our results are compared with data for H/sup +/-H collisions.

  14. X-ray Emission Cross Sections following Charge Exchange by Multiply-Charged Ions of Astrophysical Interest.

    Science.gov (United States)

    Otranto, Sebastian; Olson, Ronald; Beiersdorfer, Peter

    2006-05-01

    State selective nl-electron capture cross sections calculated using the classical trajectory Monte Carlo (CTMC) model are presented for highly charged ions with Z = 6-10 colliding with atoms and molecules. The energy dependence of the l-level populations is investigated. The calculated cross sections are compared with measurements made by Greenwood et al [1], using O^8+ and Ne^10+ on various targets at 3 keV/amu, and with recent x-ray emission cross sections measured with the EBIT machine at LLNL using O^8+ and Ne^9+,10+ on different targets at 10 eV/amu. We use the calculated cross sections to present an ab initio determination of the soft x-ray spectrum of comet C/Linear 1999 S4 that was observed on the Chandra X-ray Observatory [2]. [1] J. B. Greenwood, I. D. Williams, S. J. Smith and A. Chutjian, Phys. Rev. A 63, 062707 (2001). [2] C. M. Lisse, D. J. Christian, K. Dennerl, K. J. Meech, R. Petre, H. A. Weaver and S. J. Wolk, Science 292, 1343 (2001).

  15. Single top quark production cross section using the ATLAS detector at the LHC

    CERN Document Server

    Cioara, Irina Antonela; The ATLAS collaboration

    2017-01-01

    Measurements of single top-quark production in proton-proton collisions are presented based on the 8 TeV and 13 TeV ATLAS datasets. In the leading order process, a W boson is exchanged in the t-channel. The cross-section for the production of single top-quarks and single anti-top-quarks total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. At 8 TeV, differential cross-section measurements of the t-channel process are also reported, these analyses include limits on anomalous contributions to the Wtb vertex and measurement of the top quark polarization. A measurement of the production cross section of a single top quark in association with a W boson, the second largest single-top production mode, is also presented. Finally, evidence for s-channel single-top production in the 8 TeV ATLAS dataset is presented. All measurements are compared to state-of-the-art theoretical calculations.

  16. Charge transfer cross-sections of argon ions colliding on argon atoms

    International Nuclear Information System (INIS)

    Aubert, J.; Bliman, S.; Chan-Tung, N.; Geller, R.; Jacquot, B.; Van Houtte, D.

    1980-04-01

    A device has been built to measure charge changing cross-sections of Argon ions colliding on argon atoms. It consists of an E.C.R. ion source (Micromafios) that delivers argon ions up to charge + 13. The ion source potential may be varied from 1 up to 10 kVolts. A first magnet is used to charge analyze the extracted beam. For a given separated charge state, the ion beam is passed in a collision cell whose pressure may be varied. The ions undergoing collisions on the target are analyzed by a second magnet and collected. The pressure is varied in the collision cell in order to check that the single collision condition is satisfied. It is shown that the ions do two types of collisions: charge exchange and stripping whose cross-sections are measured. Interpretation of charge exchange is proposed along yet classic theoretical approaches. As to stripping no available theory allows interpretation

  17. Single Top quark production cross section using the ATLAS detector at the LHC

    CERN Document Server

    Monini, C; The ATLAS collaboration

    2014-01-01

    Measurements of single top-quark production cross section in proton proton collisions at 7 and 8 TeV are presented. In the leading order process, a W boson is exchanged in the t-channel. The single top-quark and anti-top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. In addition, a measurement of the production cross section of a single top quark in association with a W boson is presented. All measurements are compared to NLO and NLO+NNLO calculations and the CKM matrix element |Vtb| is determined. In addition, the s-channel production is explored and limits on exotic production in single top quark processes are discussed. This includes the search for flavor changing neutral currents and the search for additional W’ bosons in the s-channel.

  18. Status of GRACE system - automatic computation of cross sections

    International Nuclear Information System (INIS)

    Fujimoto, J.; Ishikawa, T.; Kawabata, S.; Kurihara, Y.; Shimizu, Y.; Kato, K.; Nakazawa, N.; Kaneko, T.; Tanaka, H.

    1995-01-01

    Automated system is an essential tool for high-energy physics and GRACE system for tree processes makes it possible to calculate cross sections for complicated processes exactly. To check the output of the automatic system we make comparison between Hooft-t-Feynman gauge and unitary gauge, the exchange of external particles, and we check the independence of UV divergence parameter and that of IR divergence parameter

  19. Standard cross-section data

    International Nuclear Information System (INIS)

    Carlson, A.D.

    1984-01-01

    The accuracy of neutron cross-section measurement is limited by the uncertainty in the standard cross-section and the errors associated with using it. Any improvement in the standard immediately improves all cross-section measurements which have been made relative to that standard. Light element, capture and fission standards are discussed. (U.K.)

  20. Cross-section measurements of neutron-deuteron breakup at 13.0 MeV

    International Nuclear Information System (INIS)

    Setze, H.R.; Howell, C.R.; Tornow, W.; Braun, R.T.; Gonzalez Trotter, D.E.; Hussein, A.H.; Pedroni, R.S.; Roper, C.D.; Salinas, F.; Slaus, I.; Vlahovic, B.; Walter, R.L.; Mertens, G.; Lambert, J.M.; Witala, H.; Gloeckle, W.

    2005-01-01

    Cross-section measurements of seven exit-channel configurations in the neutron-deuteron breakup at 13.0 MeV are reported and compared to rigorous calculations. Our data are consistent with those of previous measurements in four of six configurations. The present data for five configurations are in good agreement with theoretical predictions. The cross-section data for the space-star and another out-of-plane configuration are larger than the theoretical predictions by more than three standard deviations. The previously observed 20% discrepancy between theory and data for the space-star configuration is confirmed in the present work. The inclusion of the Tucson-Melbourne 2π-exchange three-nucleon force changes the predicted cross section by only 2% and in the wrong direction needed to bring theory into agreement with data

  1. Cross-correlations between RMB exchange rate and international commodity markets

    Science.gov (United States)

    Lu, Xinsheng; Li, Jianfeng; Zhou, Ying; Qian, Yubo

    2017-11-01

    This paper employs multifractal detrended analysis (MF-DFA) and multifractal detrended cross-correlation analysis (MF-DCCA) to study cross-correlation behaviors between China's RMB exchange rate market and four international commodity markets, using a comprehensive set of data covering the period from 22 July 2005 to 15 March 2016. Our empirical results from MF-DFA indicate that the RMB exchange rate is the most inefficient among the 4 selected markets. The results from quantitative analysis have testified the existence of cross-correlations and the result from MF-DCCA have further confirmed a strong multifractal behavior between RMB exchange rate and international commodity markets. We also demonstrate that the recent financial crisis has significant impact on the cross-correlated behavior. Through the rolling window analysis, we find that the RMB exchange rates and international commodity prices are anti-persistent cross-correlated. The main sources of multifractality in the cross-correlations are long-range correlations between RMB exchange rate and the aggregate commodity, energy and metals index.

  2. Microscopic calculation of sub-barrier fusion cross section and barrier distribution using M3Y-type forces

    International Nuclear Information System (INIS)

    Ismail, M.; Ramadan, Kh.A.

    2000-01-01

    The heavy-ion (HI) potential between spherical and deformed nuclei is derived using an M3Y-type nucleon-nucleon (NN) interaction. The calculation of the exchange part of the HI potential was improved by using a finite-range NN exchange force instead of the zero-range pseudo-potential which is usually used in deriving the potential between deformed nuclei. We consider an 154 Sm- 16 O nuclear pair as an example to show the effect of finite range on the nucleus-nucleus potential for different deformation parameters and at different orientation angles of the deformed target nucleus. We calculated the fusion cross section and the barrier distribution in the WKB approximation and studied their dependence on the orientation and deformation of the target nucleus. The variations found due to improving the exchange part enhance the fusion cross section below the Coulomb barrier by a factor of about four. It has been found that both the cross section and the barrier distribution are very sensitive to the deformation parameters at energies below the Coulomb barrier. (author)

  3. Microscopic calculation of sub-barrier fusion cross section and barrier distribution using M3Y-type forces

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, M.; Ramadan, Kh.A. [Physics Department, Faculty of Science, Cairo University, Giza (Egypt)

    2000-10-01

    The heavy-ion (HI) potential between spherical and deformed nuclei is derived using an M3Y-type nucleon-nucleon (NN) interaction. The calculation of the exchange part of the HI potential was improved by using a finite-range NN exchange force instead of the zero-range pseudo-potential which is usually used in deriving the potential between deformed nuclei. We consider an {sup 154}Sm-{sup 16}O nuclear pair as an example to show the effect of finite range on the nucleus-nucleus potential for different deformation parameters and at different orientation angles of the deformed target nucleus. We calculated the fusion cross section and the barrier distribution in the WKB approximation and studied their dependence on the orientation and deformation of the target nucleus. The variations found due to improving the exchange part enhance the fusion cross section below the Coulomb barrier by a factor of about four. It has been found that both the cross section and the barrier distribution are very sensitive to the deformation parameters at energies below the Coulomb barrier. (author)

  4. Cross sections for atmospheric corrections

    International Nuclear Information System (INIS)

    Meyer, J.P.; Casse, M.; Westergaard, N.

    1975-01-01

    A set of cross sections for spallation of relativistic nuclei is proposed based on (i) the best available proton cross sections, (ii) an extrapolation to heavier nuclei of the dependence on the number of nucleons lost of the 'target factor' observed for C 12 and O 16 by Lindstrom et al. (1975), in analogy with Rudstam's formalism, and (iii) on a normalization of all cross sections to the total cross sections for production of fragments with Asub(f) >= 6. The obtained cross sections for peripheral interactions are not inconsistent with simple geometrical considerations. (orig.) [de

  5. Single Top quark production cross section using ATLAS detector at the LHC

    CERN Document Server

    Estrada Pastor, Oscar; The ATLAS collaboration

    2018-01-01

    Measurements of single top-quark production in proton-proton collisions are presented based on the 8 TeV and 13 TeV ATLAS datasets. In the leading order process, a W boson is exchanged in the t-channel. The cross-section for the production of single top-quarks and single anti-top-quarks, their ratio, as well as differential cross-section measurements are also reported. These analyses include limits on anomalous contributions to the Wtb vertex and measurement of the top quark polarization. Measurements of the inclusive and differential cross-sections for the production of a single top quark in association with a W boson, the second largest single-top production mode, are also presented. Finally, evidence for s-channel single-top production in the 8 TeV ATLAS dataset is presented. All measurements are compared to state-of-the-art theoretical calculations.

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

    International Nuclear Information System (INIS)

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

    1988-01-01

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

  7. Atlas cross section for scattering of muonic hydrogen atoms on hydrogen isotope molecules

    International Nuclear Information System (INIS)

    Adamczak, A.; Faifman, M.P.; Ponomarev, L.I.

    1996-01-01

    The total cross sections of the elastic, spin-flip, and charge-exchange processes for the scattering of muonic hydrogen isotope atoms (pμ, dμ, tμ) in the ground state on the hydrogen isotope molecules (H 2 , D 2 , T 2 , HD, HT, DT) are calculated. The scattering cross sections of muonic hydrogen isotope atoms on hydrogen isotope nuclei obtained earlier in the multichannel adiabatic approach are used in the calculations. Molecular effects (electron screening, rotational and vibrational excitations of target molecules, etc.) are taken into account. The spin effects of the target molecules and of the incident muonic atoms are included. the cross sections are averaged over the Boltzmann distribution of the molecule rotational states and the Maxwellian distribution of the target molecule kinetic energies for temperatures 30, 100, 300, and 1000 K. The cross sections are given for kinetic energies of the incident muonic atoms ranging from 0.001 to 100 eV in the laboratory frame. 45 refs., 6 tabs

  8. Measurement of Dijet Cross Sections in ep Interactions with a Leading Neutron at HERA

    CERN Document Server

    Aktas, A.; Anthonis, T.; Aplin, S.; Asmone, A.; Babaev, A.; Backovic, S.; Bahr, J.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, Ch.; Berger, N.; Bizot, J.C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Brown, D.P.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Caron, S.; Cassol-Brunner, F.; Cerny, K.; Chekelian, V.; Contreras, J.G.; Coughlan, J.A.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; Delcourt, B.; Demirchyan, R.; De Roeck, A.; Desch, K.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Ellerbrock, M.; Elsen, E.; Erdmann, W.; Essenov, S.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Finke, L.; Fleischer, M.; Fleischmann, P.; Fleming, Y.H.; Flucke, G.; Fomenko, A.; Foresti, I.; Formanek, J.; Franke, G.; Frising, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerhards, R.; Gerlich, C.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Goyon, C.; Grab, C.; Greenshaw, T.; Gregori, M.; Grindhammer, Guenter; Gwilliam, C.; Haidt, D.; Hajduk, L.; Haller, J.; Hansson, M.; Heinzelmann, G.; Henderson, R.C.W.; Henschel, H.; Henshaw, O.; Herrera, G.; Herynek, I.; Heuer, R.-D.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, H.; Kapichine, M.; Karlsson, M.; Katzy, J.; Keller, N.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Koutouev, R.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Kuckens, J.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Laycock, P.; Lebedev, A.; Leiner, B.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; List, B.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Luke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marshall, R.; Martisikova, M.; Martyn, H.-U.; Maxeld, S.J.; Meer, D.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, J.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nikitin, D.; Nowak, G.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Pascaud, C.; Patel, G.D.; Peez, M.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Poschl, R.; Portheault, B.; Povh, B.; Prideaux, P.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauvan, E.; Schatzel, S.; Scheins, J.; Schilling, F.-P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schroder, V.; Schultz-Coulon, H.-C.; Schwanenberger, C.; Sedlak, K.; Sefkow, F.; Sheviakov, I.; Shtarkov, L.N.; Sirois, Y.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Stella, B.; Stiewe, J.; Strauch, I.; Straumann, U.; Tchoulakov, V.; Thompson, Graham; Thompson, P.D.; Tomasz, F.; Traynor, D.; Truoel, Peter; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, Marcel; Usik, A.; Utkin, D.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Van Remortel, N.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vest, A.; Vinokurova, S.; Volchinski, V.; Vujicic, B.; Wacker, K.; Wagner, J.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Werner, N.; Wessels, M.; Wessling, B.; Wigmore, C.; Winter, G.-G.; Wissing, Ch.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zimmermann, J.; Zohrabyan, H.; Zomer, F.

    2005-01-01

    Measurements are reported of the production of dijet events with a leading neutron in ep interactions at HERA. Differential cross sections for photoproduction and deep inelastic scattering are presented as a function of several kinematic variables. Leading order QCD simulation programs are compared with the measurements. Models in which the real or virtual photon interacts with a parton of an exchanged pion are able to describe the data. Next-to-leading order perturbative QCD calculations based on pion exchange are found to be in good agreement with the measured cross sections. The fraction of leading neutron dijet events with respect to all dijet events is also determined. The dijet events with a leading neutron have a lower fraction of resolved photon processes than do the inclusive dijet data.

  9. Multitrajectory eikonal cross sections

    International Nuclear Information System (INIS)

    Turner, R.E.

    1983-01-01

    With the use of reference and distorted transition operators, a time-correlation-function representation of the inelastic differential cross section has recently been used to obtain distorted eikonal cross sections. These cross sections involve straight-line and reference classical translational trajectories that are unaffected by any internal-state changes which have occurred during the collision. This distorted eikonal theory is now extended to include effects of internal-state changes on the translational motion. In particular, a different classical trajectory is associated with each pair of internal states. Expressions for these inelastic cross sections are obtained in terms of time-ordered cosine and sine memory functions using the Zwanzig-Feshbach projection-operator method. Explicit formulas are obtained in the time-disordered perturbation approximation

  10. FEMA DFIRM Cross Sections

    Data.gov (United States)

    Minnesota Department of Natural Resources — FEMA Cross Sections are required for any Digital Flood Insurance Rate Map database where cross sections are shown on the Flood Insurance Rate Map (FIRM). Normally...

  11. Macroscopic cross sections for analyzing the transport of neutral particles in plasmas

    International Nuclear Information System (INIS)

    Suzuki, Tadakazu; Taji, Yuukichi; Nakahara, Yasuaki

    1975-05-01

    Algorithms have been developed for calculating the ionization and charge exchange cross sections required for analyzing the neutral transport in plasmas. In our algorithms, the integration of the expression for reaction rate of neutrals with plasmas is performed by expanding the integrand with the use of polynomials. At present, multi-energy-group sets of the cross sections depending on plasma temperature and energy of neutrals can be prepared by means of Maxwellian averages over energy. Calculational results are printed out in the FIDO format. Some numerical examples are given for several forms of spatial distributions assumed for the plasma ion temperature and source neutral energy. (auth.)

  12. Analysis of Asset Growth Anomaly on Cross-Section Stock Returns: Evidence from Indonesia Stock Exchange

    Directory of Open Access Journals (Sweden)

    Muhammad Iqbal

    2017-06-01

    Full Text Available Assorted types of market anomalies occur when stock prices deviate from the prediction of classical asset pricing theories. This study aims to examine asset growth anomaly where stocks with high asset growth will be followed by low returns in the subsequent periods. This study, using Indonesia Stock Exchanges data, finds that an equally-weighted low-growth portfolio outperforms high-growth portfolio by average 0.75% per month (9% per annum, confirming existence of asset growth anomaly. The analysis is extended at individual stock-level using fixed-effect panel regression in which asset growth effect remains significant even with controlling other variables of stock return determinants. This study also explores further whether asset growth can be included as risk factor. Employing two-stage cross-section regression in Fama and Macbeth (1973, the result aligns with some prior studies that asset growth is not a new risk factor; instead the anomaly is driven by mispricing due to investors’ overreaction and psychological bias. This result imply that asset growth anomaly is general phenomenon that can be found at mostly all stock market but in Indonesia market asset growth anomaly rise from investors’ overreaction, instead of  playing as a factor of risk.

  13. Analysis of Asset Growth Anomaly on Cross-Section Stock Returns: Evidence from Indonesia Stock Exchange

    Directory of Open Access Journals (Sweden)

    Muhammad Iqbal

    2017-03-01

    Full Text Available Assorted types of market anomalies occur when stock prices deviate from the prediction of classical asset pricing theories. This study aims to examine asset growth anomaly where stocks with high asset growth will be followed by low returns in the subsequent periods. This study, using Indonesia Stock Exchanges data, finds that an equally-weighted low-growth portfolio outperforms high-growth portfolio by average 0.75% per month (9% per annum, confirming existence of asset growth anomaly. The analysis is extended at individual stock-level using fixed-effect panel regression in which asset growth effect remains significant even with controlling other variables of stock return determinants. This study also explores further whether asset growth can be included as risk factor. Employing two-stage cross-section regression in Fama and Macbeth (1973, the result aligns with some prior studies that asset growth is not a new risk factor; instead the anomaly is driven by mispricing due to investors’ overreaction and psychological bias. This result imply that asset growth anomaly is general phenomenon that can be found at mostly all stock market but in Indonesia market asset growth anomaly rise from investors’ overreaction, instead of  playing as a factor of risk.

  14. Asymptotic form of the charge exchange cross section in the three body rearrangement collisions

    Science.gov (United States)

    Omidvar, K.

    1975-01-01

    A three body general rearrangement collision is considered where the initial and final bound states are described by the hydrogen-like wave functions. Mathematical models are developed to establish the relationships of quantum number, the reduced mass, and the nuclear charge of the final state. It is shown that for the low lying levels, the reciprocal of n cubed scaling law at all incident energies is only approximately satisfied. The case of the symmetric collisions is considered and it is shown that for high n and high incident energy, E, the cross section behaves as the reciprocal of E cubed. Zeros and minima in the differential cross sections in the limit of high n for protons on atomic hydrogen and positrons on atomic hydrogen are given.

  15. Comparison of integral cross section values of several cross section libraries in the SAND-II format

    International Nuclear Information System (INIS)

    Zijp, W.L.; Nolthenius, H.J.

    1976-09-01

    A comparison of some integral cross-section values for several cross-section libraries in the SAND-II format is presented. The integral cross-section values are calculated with the aid of the spectrum functions for a Watt fission spectrum, a 1/E spectrum and a Maxwellian spectrum. The libraries which are considered here are CCC-112B, ENDF/B-IV, DETAN74, LAPENAS and CESNEF. These 5 cross-section libraries used have all the SAND-II format. Discrepancies between cross-sections in the different libraries are indicated but not discussed

  16. Single top-quark production cross section measurements using the ATLAS detector at the LHC

    CERN Document Server

    Rieck, Patrick; The ATLAS collaboration

    2016-01-01

    Measurements of single top­quark production in proton proton collisions are presented. The measurements include the first such measurements from the 13 TeV ATLAS dataset. In the leading order process, a W boson is exchanged in the t­channel. The single top­quark and anti­top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. At 8 TeV, differential cross­section measurements of the t­channel process are also presented, these measurements include limits on anomalous contributions to the Wtb vertex. A measurement of the production cross section of a single top quark in association with a W boson, the second largest single­top production mode, is also presented. Finally, evidence for single­top production in the 8 TeV ATLAS dataset is presented. All measurements are compared to state­of­ the­art theoretical calculations.

  17. Relativistic photon-Maxwellian electron cross sections

    International Nuclear Information System (INIS)

    Wienke, B.R.; Lathrop, B.L.; Devaney, J.J.

    1986-01-01

    Temperature corrected cross sections, complementing the Klein-Nishina set, are developed for astrophysical, plasma, and transport applications. The set is obtained from a nonlinear least squares fit to the exact photon-Maxwellian electron cross sections, using the static formula as the asymptotic basis. Two parameters are sufficient (two decimal places) to fit the exact cross sections over a range of 0-100 keV in electron temperature, and 0-1 MeV in incident photon energy. The fit is made to the total cross sections, yet the parameters predict both total and differential scattering cross sections well. Corresponding differential energy cross sections are less accurate. An extended fit to (just) the total cross sections, over the temperature and energy range 0-5 MeV, is also described. (author)

  18. Geometry effects on the (e, 2e) cross section on ionic targets

    International Nuclear Information System (INIS)

    Khajuria, Y.

    2005-01-01

    The three body distorted wave Born approximation (DWBA) with spin averaged static exchange potential has been used to calculate the electron impact triple-differential cross section of Li + , Na + and K + ions in different geometries and kinematics. In coplanar geometry at high incident energy (≥ 500 eV) and scattering angle ∼10deg, both recoil and binary peaks in case of p-orbital electrons splits into two. The value of the binary to the recoil peak ratio for the specific value of the momentum transfer has been determined to understand the collision dynamics. In the non-coplanar geometry a strong interference resulting in a dip in triple differential cross section (TDCS) has been noticed. (author)

  19. Thermal performance modeling of cross-flow heat exchangers

    CERN Document Server

    Cabezas-Gómez, Luben; Saíz-Jabardo, José Maria

    2014-01-01

    This monograph introduces a numerical computational methodology for thermal performance modeling of cross-flow heat exchangers, with applications in chemical, refrigeration and automobile industries. This methodology allows obtaining effectiveness-number of transfer units (e-NTU) data and has been used for simulating several standard and complex flow arrangements configurations of cross-flow heat exchangers. Simulated results have been validated through comparisons with results from available exact and approximate analytical solutions. Very accurate results have been obtained over wide ranges

  20. Resonances in photoionization. Cross section for vibrationally excited H2

    International Nuclear Information System (INIS)

    Mezei, J.Zs.; Jungen, Ch.

    2011-01-01

    Complete text of publication follows. Diatomic molecular Hydrogen is the most abundant molecule in interstellar molecular clouds. The modeling of these environments relies on accurate cross sections for the various relevant processes. Among them, the photoionization plays a major role in the kinetics and in the energy exchanges involving H 2 . The recent discovery of vibrationally excited molecular hydrogen in extragalactic environments revealed the need for accurate evaluation of the corresponding photoionization cross sections. In the present work we report theoretical photoionization cross sections for excitation from excited vibrational levels of the ground state, dealing with the Q(N = 1) (ΔN = 0, where N is the total angular momentum of the molecule) transitions which account for roughly one third of the total photoabsorption cross section. We will focus on the v' = 1 excited level of the ground electronic state. Our calculations are based on Multichannel Quantum Defect Theory (MQDT), which allows us to take into account of the full manifold of Rydberg states and their interactions with the electronic continuum. We have carried out two types of MQDT calculations. First, we omitted all open channels and calculated energy levels, wave functions and spontaneous emission Einstein coefficients, making use of the theoretical method presented in [2]. In a second set of calculations we included the open ionization channels in the computations getting the continuum phase shifts, channel mixing coefficients and channel dipole moments and finally the photoabsorption/ photoionization cross section. The cross section is dominated by the presence of resonance structures corresponding to excitation of various vibrational levels of bound electronic states which lie above the ionization threshold. In order to assess the importance of the resonances we have calculated for each vibrational interval (the energy interval between two consecutive ionization thresholds) the

  1. Electron and positron atomic elastic scattering cross sections

    International Nuclear Information System (INIS)

    Stepanek, Jiri

    2003-01-01

    A method was developed to calculate the total and differential elastic-scattering cross sections for incident electrons and positrons in the energy range from 0.01 eV to 1 MeV for atoms of Z=1-100. For electrons, hydrogen, helium, nitrogen, oxygen, krypton, and xenon, and for positrons, helium, neon, and argon atoms were considered for comparison with experimental data. First, the variationally optimized atomic static potentials were calculated for each atom by solving the Dirac equations for bound electron states. Second, the Dirac equations for a free electron or positron are solved for an atom using the previously calculated static potential accomplished (in the case of electrons) by 'adjusted' Hara's exchange potential for a free-state particle. Additional to the exchange effects, the charge cloud polarization effects are considered applying the correlation-polarization potential of O'Connell and Lane (with correction of Padial and Norcross) for incident electrons, and of Jain for incident positrons. The total, cutoff and differential elastic-scattering cross sections are calculated for incident electrons and positrons with the help of the relativistic partial wave analysis. The solid state effects for scattering in solids are described by means of a muffin-tin model, i.e. the potentials of neighboring atoms are superpositioned in such a way that the resulting potential and its derivative are zero in the middle distance between the atoms. The potential of isolated atom is calculated up to the radius at which the long-range polarization potential becomes a value of -10 -8

  2. Integral nucleus-nucleus cross sections

    International Nuclear Information System (INIS)

    Barashenkov, V.S.; Kumawat, H.

    2003-01-01

    Expressions approximating the experimental integral cross sections for elastic and inelastic interactions of light and heavy nuclei at the energies up to several GeV/nucleon are presented. The calculated cross sections are inside the corridor of experimental errors or very close to it. Described in detail FORTRAN code and a numerical example of the cross section approximation are also presented

  3. Photon-splitting cross sections

    International Nuclear Information System (INIS)

    Johannessen, A.M.; Mork, K.J.; Overbo, I.

    1980-01-01

    The differential cross section for photon splitting (scattering of one photon into two photons) in a Coulomb field, obtained earlier by Shima, has been integrated numerically to yield various differential cross sections. Energy spectra differential with respect to the energy of one of the outgoing photons are presented for several values of the primary photon energy. Selected examples of recoil momentum distributions and some interesting doubly or multiply differential cross sections are also given. Values for the total cross section are obtained essentially for all energies. The screening effect caused by atomic electrons is also taken into account, and is found to be important for high energies, as in e + e - pair production. Comparisons with various approximate results obtained by previous authors mostly show fair agreement. We also discuss the possibilities for experimental detection and find the most promising candidate to be a measurement of both photons, and their energies, at a moderately high energy

  4. Comparison of integral cross section values of several cross section libraries in the SAND-II format

    International Nuclear Information System (INIS)

    Zijp, W.L.; Nolthenius, H.J.

    1978-01-01

    A comparison of some integral cross section values for several cross section libraries in the SAND-II format is presented. The integral cross section values are calculated with aid of the spectrum functions for a Watt fission spectrum, a 1/E spectrum and a Maxwellian spectrum. The libraries which are considered here are CCC-112B, ENDF/B-IV, DETAN74, LAPENAS and CESNEF. These 5 cross section libraries used have all the SAND-II format. (author)

  5. Jet inclusive cross sections

    International Nuclear Information System (INIS)

    Del Duca, V.

    1992-11-01

    Minijet production in jet inclusive cross sections at hadron colliders, with large rapidity intervals between the tagged jets, is evaluated by using the BFKL pomeron. We describe the jet inclusive cross section for an arbitrary number of tagged jets, and show that it behaves like a system of coupled pomerons

  6. Electron collision cross sections of mercury

    International Nuclear Information System (INIS)

    Suzuki, Susumu; Kuzuma, Kiyotaka; Itoh, Haruo

    2006-01-01

    In this paper, we propose a new collision cross section set for mercury which revises the original set summarized by Hayashi in 1989. Hanne reported three excitation collision cross sections (6 3 P 0 , 6 3 P 1 , 6 3 P 2 ) determined from an electron beam experiment in 1988. As a matter for regret, no attentive consideration was given to combining these three excitation cross sections with the cross section set of Hayashi. Therefore we propose a new set where these three excitation cross sections are included. In this study, other two excitation cross sections (6 1 P 1 , 6 3 D 3 ) except for the three excitation collision cross sections (6 3 P 0 , 6 3 P 1 , 6 3 P 2 ) are taken from the original set of Hayashi. The momentum transfer cross section and the ionization collision cross section are also taken from Hayashi. A Monte Carlo Simulation (MCS) technique is applied for evaluating our new cross section set. The present results of the electron drift velocity and the ionization coefficient are compared to experimental values. Agreement is secured in relation to the electron drift velocity for 1.5 Td 2 ) is the reduced electric field, E (V/cm) is the electric field, N (1/cm 3 ) is the number density of mercury atoms at 0degC, 1 Torr, E/N is also equal to 2.828 x 10 -17 E/p 0 from the relation of the ideal gas equation, p 0 (Torr) is gas pressure at 0degC, 1 Torr=1.33322 x 10 -2 N/cm -2 and 10 -17 V/cm 2 is called 1 Td. Thus it is ensured that our new cross section set is reasonable enough to be used up to 100 eV when considering with the electron drift velocity and the ionization coefficient. (author)

  7. Background-cross-section-dependent subgroup parameters

    International Nuclear Information System (INIS)

    Yamamoto, Toshihisa

    2003-01-01

    A new set of subgroup parameters was derived that can reproduce the self-shielded cross section against a wide range of background cross sections. The subgroup parameters are expressed with a rational equation which numerator and denominator are expressed as the expansion series of background cross section, so that the background cross section dependence is exactly taken into account in the parameters. The advantage of the new subgroup parameters is that they can reproduce the self-shielded effect not only by group basis but also by subgroup basis. Then an adaptive method is also proposed which uses fitting procedure to evaluate the background-cross-section-dependence of the parameters. One of the simple fitting formula was able to reproduce the self-shielded subgroup cross section by less than 1% error from the precise evaluation. (author)

  8. Cross-section methodology in SIMMER

    International Nuclear Information System (INIS)

    Soran, P.D.

    1975-11-01

    The cross-section methodology incorporated in the SIMMER code is described. Data base for all cross sections is the ENDF/B system with various progressing computer codes to group collapse and modify the group constants which are used in SIMMER. Either infinitely dilute cross sections or the Bondarenko formalism can be used in SIMMER. Presently only a microscopic treatment is considered, but preliminary macroscopic algorithms have been investigated

  9. Cross-section methodology in SIMMER

    International Nuclear Information System (INIS)

    Soran, P.D.

    1976-05-01

    The cross-section methodology incorporated in the SIMMER code is described. Data base for all cross sections is the ENDF/B system with various progressing computer codes to group collapse and modify the group constants which are used in SIMMER. Either infinitely dilute cross sections or the Bondarenko formalism can be used in SIMMER. Presently only a microscopic treatment is considered, but preliminary macroscopic algorithms have been investigated

  10. Vibrational state-resolved differential cross sections for the D + H2 → DH + H reaction

    International Nuclear Information System (INIS)

    Continetti, R.E.

    1989-11-01

    In this thesis, crossed-molecular-beams studies of the reaction D + H 2 → DH + H at collision energies of 0.53 and 1.01 eV are reported. Chapter 1 provides a survey of important experimental and theoretical studies on the dynamics of the hydrogen exchange reaction. Chapter 2 discusses the development of the excimer-laser photolysis D atom beam source that was used in these studies and preliminary experiments on the D + H 2 reaction. In Chapter 3, the differential cross section measurements are presented and compared to recent theoretical predictions. The measured differential cross sections for rotationally excited DH products showed significant deviations from recent quantum scattering calculations, in the first detailed comparison of experimental and theoretical differential cross sections. These results indicate that further work on the H 3 potential energy surface, particularly the bending potential, is in order

  11. Electron-impact cross sections of Ne

    International Nuclear Information System (INIS)

    Tsurubuchi, S.; Arakawa, K.; Kinokuni, S.; Motohashi, K.

    2000-01-01

    Electron-impact absolute emission cross sections were measured for the 3p→3s transitions of Ne. Excitation functions of the 3s→2p first resonance lines were measured in the energy range from the threshold to 1000 eV by a polarization-free optical method and relative cross sections were normalized to the absolute values, (41.0±5.4)x10 -19 cm 2 for the 73.6 nm line and (7.1±1.0)x10 -19 cm 2 for the 74.4 nm line, which were determined at 500 eV. The integrated level-excitation cross sections of Suzuki et al for the 1s 2 and 1s 4 levels were combined with the corresponding 3p→3s cascade cross sections obtained in this paper to give absolute emission cross sections for the resonance lines. The level-excitation cross sections of the 1s 2 and 1s 4 states in Paschen notation were determined from the threshold to 1000 eV by subtracting 3p→3s cascade cross sections from the corresponding 3s→2p emission cross sections of the resonance lines. A large cascade contribution is found in the emission cross section of the resonance lines. It is 28.5% for the 73.6 nm line and 49.6% for the 74.4 nm line at 40 eV, and 17.0 and 61.8%, respectively, at 300 eV. (author)

  12. Single Top quark production cross-section measurements using the ATLAS detector at the LHC

    CERN Document Server

    Jimenez Pena, Javier; The ATLAS collaboration

    2018-01-01

    Measurements of single top-quark production in proton-proton collisions are presented based on the 13 TeV and 8 TeV ATLAS datasets. In the leading order process, a W-boson is exchanged in the t-channel. The cross-section for the production of single top-quarks and single antitop-quarks, their ratio, as well as differential cross-section measurements are also reported. Measurements of the inclusive and differential cross-sections for the production of a single top quark in association with a W-boson, the second largest single top production mode are also presented. Evidence for the s-channel single top-quark production in the 8 TeV dataset is presented. Finally, the first measurement of the tZq electroweak production is presented. All measurements are compared to state-of-the art theoretical calculations. (On behalf of the ATLAS collaboration)

  13. Neutron cross sections: Book of curves

    International Nuclear Information System (INIS)

    McLane, V.; Dunford, C.L.; Rose, P.F.

    1988-01-01

    Neuton Cross Sections: Book of Curves represents the fourth edition of what was previously known as BNL-325, Neutron Cross Sections, Volume 2, CURVES. Data is presented only for (i.e., intergrated) reaction cross sections (and related fission parameters) as a function of incident-neutron energy for the energy range 0.01 eV to 200 MeV. For the first time, isometric state production cross sections have been included. 11 refs., 4 figs

  14. Evaluated cross section libraries

    International Nuclear Information System (INIS)

    Maqurno, B.A.

    1976-01-01

    The dosimetry tape (ENDF/B-IV tape 412) was issued in a general CSEWG distribution, August 1974. The pointwise cross section data file was tested with specified reference spectra. A group averaged cross section data file (620 groups based on tape 412) was tested with the above spectra and the results are presented in this report

  15. Nuclear Forensics and Radiochemistry: Cross Sections

    Energy Technology Data Exchange (ETDEWEB)

    Rundberg, Robert S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-08

    The neutron activation of components in a nuclear device can provide useful signatures of weapon design or sophistication. This lecture will cover some of the basics of neutron reaction cross sections. Nuclear reactor cross sections will also be presented to illustrate the complexity of convolving neutron energy spectra with nuclear excitation functions to calculate useful effective reactor cross sections. Deficiencies in the nuclear database will be discussed along with tools available at Los Alamos to provide new neutron cross section data.

  16. Differential Top Cross-section Measurements

    CERN Document Server

    Fenton, Michael James; The ATLAS collaboration

    2017-01-01

    The top quark is the heaviest known fundamental particle. The measurement of the differential top-quark pair production cross-section provides a stringent test of advanced perturbative QCD calculations. The ATLAS collaboration has performed detailed measurements of those differential cross sections at a centre-of-mass energy of 13 TeV. This talk focuses on differential cross-section measurements in the lepton+jets final state, including using boosted top quarks to probe our understanding of top quark production in the TeV regime.

  17. Measurement and QCD analysis of the diffractive deep-inelastic scattering cross section at HERA

    International Nuclear Information System (INIS)

    Aktas, A.; Andreev, V.; Anthonis, T.

    2006-05-01

    A detailed analysis is presented of the diffractive deep-inelastic scattering process ep→eXY, where Y is a proton or a low mass proton excitation carrying a fraction 1-x P >0.95 of the incident proton longitudinal momentum and the squared four-momentum transfer at the proton vertex satisfies t 2 . Using data taken by the H1 experiment, the cross section is measured for photon virtualities in the range 3.5 ≤Q 2 ≤1600 GeV 2 , triple differentially in x P , Q 2 and β=x/x P , where x is the Bjorken scaling variable. At low x P , the data are consistent with a factorisable x P dependence, which can be described by the exchange of an effective pomeron trajectory with intercept α P (0)=1.118 ±0.008(exp.) +0.029 -0.010 (model). Diffractive parton distribution functions and their uncertainties are determined from a next-to-leading order DGLAP QCD analysis of the Q 2 and β dependences of the cross section. The resulting gluon distribution carries an integrated fraction of around 70% of the exchanged momentum in the Q 2 range studied. Total and differential cross sections are also measured for the diffractive charged current process e + p → anti ν e XY and are found to be well described by predictions based on the diffractive parton distributions. The ratio of the diffractive to the inclusive neutral current ep cross sections is studied. Over most of the kinematic range, this ratio shows no significant dependence on Q 2 at fixed x P and x or on x at fixed Q 2 and β. (Orig.)

  18. Measurement and QCD analysis of the diffractive deep-inelastic scattering cross section at HERA

    Science.gov (United States)

    Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J. C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Bruncko, D.; Büsser, F. W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J. G.; Coughlan, J. A.; Coppens, Y. R.; Cox, B. E.; Cozzika, G.; Cvach, J.; Dainton, J. B.; Dau, W. D.; Daum, K.; de Boer, Y.; Delcourt, B.; Del Degan, M.; de Roeck, A.; de Wolf, E. A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P. J. W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Flucke, G.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, S.; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B. R.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janssen, X.; Jemanov, V.; Jönsson, L.; Johnson, C. L.; Johnson, D. P.; Jung, A. W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laštovička-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Marage, P.; Marshall, R.; Marti, L.; Martisikova, M.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meier, K.; Meyer, A. B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J. V.; Mozer, M. U.; Müller, K.; Murín, P.; Nankov, K.; Naroska, B.; Naumann, T.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J. E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G. D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Plačakytė, R.; Portheault, B.; Povh, B.; Prideaux, P.; Rahmat, A. J.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schilling, F.-P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R. N.; Sheviakov, I.; Shtarkov, L. N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Stiewe, J.; Stoilov, A.; Straumann, U.; Sunar, D.; Tchoulakov, V.; Thompson, G.; Thompson, P. D.; Toll, T.; Tomasz, F.; Traynor, D.; Trinh, T. N.; Truöl, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Urban, M.; Usik, A.; Utkin, D.; Valkárová, A.; Vallée, C.; van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wessling, B.; Wissing, C.; Wolf, R.; Wünsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Žáček, J.; Zálešák, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y. C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

    2006-12-01

    A detailed analysis is presented of the diffractive deep-inelastic scattering process ep→eXY, where Y is a proton or a low mass proton excitation carrying a fraction 1-xIP>0.95 of the incident proton longitudinal momentum and the squared four-momentum transfer at the proton vertex satisfies |t|<1 GeV2. Using data taken by the H1 experiment, the cross section is measured for photon virtualities in the range 3.5≤Q2≤1600 GeV2, triple differentially in xIP, Q2 and β=x/xIP, where x is the Bjorken scaling variable. At low xIP, the data are consistent with a factorisable xIP dependence, which can be described by the exchange of an effective pomeron trajectory with intercept αIP(0)=1.118±0.008(exp.)+0.029 -0.010(model). Diffractive parton distribution functions and their uncertainties are determined from a next-to-leading order DGLAP QCD analysis of the Q2 and β dependences of the cross section. The resulting gluon distribution carries an integrated fraction of around 70% of the exchanged momentum in the Q2 range studied. Total and differential cross sections are also measured for the diffractive charged current process e+p→ν¯eXY and are found to be well described by predictions based on the diffractive parton distributions. The ratio of the diffractive to the inclusive neutral current ep cross sections is studied. Over most of the kinematic range, this ratio shows no significant dependence on Q2 at fixed xIP and x or on x at fixed Q2 and β.

  19. Activation cross section data file, (1)

    International Nuclear Information System (INIS)

    Yamamuro, Nobuhiro; Iijima, Shungo.

    1989-09-01

    To evaluate the radioisotope productions due to the neutron irradiation in fission of fusion reactors, the data for the activation cross sections ought to be provided. It is planning to file more than 2000 activation cross sections at final. In the current year, the neutron cross sections for 14 elements from Ni to W have been calculated and evaluated in the energy range 10 -5 to 20 MeV. The calculations with a simplified-input nuclear cross section calculation system SINCROS were described, and another method of evaluation which is consistent with the JENDL-3 were also mentioned. The results of cross section calculation are in good agreement with experimental data and they were stored in the file 8, 9 and 10 of ENDF/B format. (author)

  20. A Monte Carlo calculation of the pionium break-up probability with different sets of pionium target cross sections

    International Nuclear Information System (INIS)

    Santamarina, C; Schumann, M; Afanasyev, L G; Heim, T

    2003-01-01

    Chiral perturbation theory predicts the lifetime of pionium, a hydrogen-like π + π - atom, to better than 3% precision. The goal of the DIRAC experiment at CERN is to obtain and check this value experimentally by measuring the break-up probability of pionium in a target. In order to accurately measure the lifetime one needs to know the relationship between the break-up probability and the lifetime to 1% accuracy. We have obtained this dependence by modelling the evolution of pionic atoms in the target using Monte Carlo methods. The model relies on the computation of the pionium-target-atom interaction cross sections. Three different sets of pionium-target cross sections with varying degrees of complexity were used: from the simplest first-order Born approximation involving only the electrostatic interaction to a more advanced approach, taking into account multiphoton exchanges and relativistic effects. We conclude that, in order to obtain the pionium lifetime to 1% accuracy from the break-up probability, the pionium-target cross sections must be known with the same accuracy for the low excited bound states of the pionic atom. This result has been achieved, for low Z targets, with the two most precise cross section sets. For large Z targets only the set accounting for multiphoton exchange satisfies the condition

  1. Utilization of cross-section covariance data in FBR core nuclear design and cross-section adjustment

    International Nuclear Information System (INIS)

    Ishikawa, Makoto

    1994-01-01

    In the core design of large fast breeder reactors (FBRs), it is essentially important to improve the prediction accuracy of nuclear characteristics from the viewpoint of both reducing cost and insuring reliability of the plant. The cross-section errors, that is, covariance data are one of the most dominant sources for the prediction uncertainty of the core parameters, therefore, quantitative evaluation of covariance data is indispensable for FBR core design. The first objective of the present paper is to introduce how the cross-section covariance data are utilized in the FBR core nuclear design works. The second is to delineate the cross-section adjustment study and its application to an FBR design, because this improved design method markedly enhances the needs and importance of the cross-section covariance data. (author)

  2. Numerical investigation of heat transfer and entropy generation of laminar flow in helical tubes with various cross sections

    International Nuclear Information System (INIS)

    Kurnia, Jundika C.; Sasmito, Agus P.; Shamim, Tariq; Mujumdar, Arun S.

    2016-01-01

    Highlights: • Heat transfers of helical coiled tube with several cross section profiles are evaluated. • Helical tubes offer higher heat transfer and lower entropy generation. • Square cross-section generates the highest entropy, followed by ellipse and circular. • Study could serve as a guideline in designing an efficient helical tube heat exchanger. - Abstract: This study evaluates heat transfer performance and entropy generation of laminar flow in coiled tubes with various cross-sections geometries i.e. circular, ellipse and square, relatives to the straight tubes of similar cross-sections. A computational fluid dynamics model is developed and validated against empirical correlations. Good agreement is obtained within range of Reynolds and Dean numbers considered. Effect of geometry, wall temperature, Reynolds number and heating/cooling mode were examined. To evaluate the heat transfer performance of the coiled tube configurations, a parameter referred as Figure of Merit (FoM) is defined as the ratio heat transfer rate to the required pumping power. In addition, exergy analysis is carried out to examine the inefficiency of the coiled tube configurations. The results indicate that coiled tubes provide higher heat transfer rate. In addition, it was found to be more efficient as reflected by lower entropy generation as compared to straight tubes. Among the studied cross-section, square cross-section generates the highest entropy, followed by ellipse and circular counterpart. Entropy production from heat transfer contribution is two order-of-magnitude higher than that of entropy contribution from viscous dissipation. Cooling case produces slightly higher entropy than heating counterpart. Finally, this study can provide practical guideline to design more efficient coiled heat exchanger.

  3. New global fit to the total photon-proton cross-section σL+T and to the structure function F2

    International Nuclear Information System (INIS)

    Gabbert, D.; Nardo, L. de

    2007-08-01

    A fit to world data on the photon-proton cross section σ L+T and the unpolarised structure function F 2 is presented. The 23-parameter ALLM model based on Reggeon and Pomeron exchange is used. Cross section data were reconstructed to avoid inconsistencies with respect to R of the published F 2 data base. Parameter uncertainties and correlations are obtained. (orig.)

  4. Inclusive-jet and dijet cross sections in deep inelastic scattering at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

    2006-08-15

    Inclusive-jet and dijet differential cross sections have been measured in neutral current deep inelastic ep scattering for exchanged boson virtualities Q{sup 2}>125 GeV{sup 2} with the ZEUS detector at HERA using an integrated luminosity of 82 pb{sup -1}. Jets were identified in the Breit frame using the k{sub T} cluster algorithm. Jet cross sections are presented as functions of several kinematic and jet variables. The results are also presented in different regions of Q{sup 2}. Next-to-leading-order QCD calculations describe the measurements well. Regions of phase space where the theoretical uncertainties are small have been identified. Measurements in these regions have the potential to constrain the gluon density in the proton when used as inputs to global fits of the proton parton distribution functions. (orig.)

  5. Inclusive-jet and dijet cross sections in deep inelastic scattering at HERA

    International Nuclear Information System (INIS)

    Chekanov, S.; Derrick, M.; Magill, S.

    2006-08-01

    Inclusive-jet and dijet differential cross sections have been measured in neutral current deep inelastic ep scattering for exchanged boson virtualities Q 2 >125 GeV 2 with the ZEUS detector at HERA using an integrated luminosity of 82 pb -1 . Jets were identified in the Breit frame using the k T cluster algorithm. Jet cross sections are presented as functions of several kinematic and jet variables. The results are also presented in different regions of Q 2 . Next-to-leading-order QCD calculations describe the measurements well. Regions of phase space where the theoretical uncertainties are small have been identified. Measurements in these regions have the potential to constrain the gluon density in the proton when used as inputs to global fits of the proton parton distribution functions. (orig.)

  6. JENDL gas-production cross section file

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo; Narita, Tsutomu

    1992-05-01

    The JENDL gas-production cross section file was compiled by taking cross-section data from JENDL-3 and by using the ENDF-5 format. The data were given to 23 nuclei or elements in light nuclei and structural materials. Graphs of the cross sections and brief description on their evaluation methods are given in this report. (author)

  7. Single Top quark production cross section and properties using the ATLAS detector at the LHC

    CERN Document Server

    Sapp, Kevin; The ATLAS collaboration

    2015-01-01

    Measurements of single top-quark production in proton proton collisions at 7 and 8 TeV are presented. In the leading order process, a W boson is exchanged in the t-channel. The single top-quark and anti-top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. In addition, a measurement of the production cross section of a single top quark in association with a W boson is presented. All measurements are compared to state-of-the-art theoretical calculations and the CKM matrix element |Vtb| is determined. In addition, the s-channel production is explored and limits on exotic production in single top quark processes are discussed. This includes the search for flavor changing neutral currents and the search for additional W’ bosons or a search for monotops.

  8. Doppler broadening of cross sections

    International Nuclear Information System (INIS)

    Buckler, P.A.C.; Pull, I.C.

    1962-12-01

    Expressions for temperature dependent cross-sections in terms of resonance parameters are obtained, involving generalisations of the conventional Doppler functions, ψ and φ. Descriptions of Fortran sub-routines, which calculate broadened cross-sections in accordance with the derived formulae, are included. (author)

  9. Heat exchanger

    International Nuclear Information System (INIS)

    Drury, C.R.

    1988-01-01

    A heat exchanger having primary and secondary conduits in heat-exchanging relationship is described comprising: at least one serpentine tube having parallel sections connected by reverse bends, the serpentine tube constituting one of the conduits; a group of open-ended tubes disposed adjacent to the parallel sections, the open-ended tubes constituting the other of the conduits, and forming a continuous mass of contacting tubes extending between and surrounding the serpentine tube sections; and means securing the mass of tubes together to form a predetermined cross-section of the entirety of the mass of open-ended tubes and tube sections

  10. Free hydrogen atom collision cross sections of interest in controlled thermonuclear research

    Energy Technology Data Exchange (ETDEWEB)

    Fite, W L [John Jay Hopkins Laboratory for Pure and Applied Science, General Atomic Division of General Dynamics Corporation, San Diego, CA (United States)

    1958-07-01

    The present paper summarizes the results of measurements of the cross sections of hydrogen atoms for: (1) ionization, (2) excitation of Lyman alpha radiation on electron impact, and (3) elastic scattering of electrons of energy less than 10 eV; and also describes the approach of measurements now in progress on (4) charge-exchange between deuterons and deuterium atoms and (5) ionization of the hydrogen atom on proton impact.

  11. Cross-sectional anatomy for computed tomography

    International Nuclear Information System (INIS)

    Farkas, M.L.

    1988-01-01

    This self-study guide recognizes that evaluation and interpretation of CT-images demands a firm understanding of both cross-sectional anatomy and the principles of computed tomography. The objectives of this book are: to discuss the basic principles of CT, to stress the importance of cross-sectional anatomy to CT through study of selected cardinal transverse sections of head, neck, and trunk, to explain orientation and interpretation of CT-images with the aid of corresponding cross-sectional preparations

  12. Density-dependent expressions for photoionization cross-sections

    International Nuclear Information System (INIS)

    Sun Weiguo; Ma Xiaoguang; Cheng Yansong

    2004-01-01

    Alternative expressions for photoionization cross-sections and dielectric influence functions are suggested to study the photoionization cross-sections of atoms in solid system. The basic picture is that the photoionization cross-section of atoms in a real system can be described as the coupling between quantum quantity (QQ) and classical quantity (CQ) parts. The QQ part represents the photoionization cross-sections of an isolated particle, while the CQ part may represent most of the important influence of the macroscopic effects (e.g., the interactions of all surrounding polarized particles, and the dielectric property, etc.) on the photoionization cross-sections. The applications to the barium system show that the number-density-dependent new photoionization formula not only obtains the same cross-sections as those from the first order approximation for ideal gas, but also can generate the cross-sections for solid barium by transforming those of ideal gas of the same species using the dielectric influence function

  13. Density-dependent expressions for photoionization cross-sections

    Energy Technology Data Exchange (ETDEWEB)

    Sun Weiguo; Ma Xiaoguang; Cheng Yansong

    2004-06-07

    Alternative expressions for photoionization cross-sections and dielectric influence functions are suggested to study the photoionization cross-sections of atoms in solid system. The basic picture is that the photoionization cross-section of atoms in a real system can be described as the coupling between quantum quantity (QQ) and classical quantity (CQ) parts. The QQ part represents the photoionization cross-sections of an isolated particle, while the CQ part may represent most of the important influence of the macroscopic effects (e.g., the interactions of all surrounding polarized particles, and the dielectric property, etc.) on the photoionization cross-sections. The applications to the barium system show that the number-density-dependent new photoionization formula not only obtains the same cross-sections as those from the first order approximation for ideal gas, but also can generate the cross-sections for solid barium by transforming those of ideal gas of the same species using the dielectric influence function.

  14. Total neutron cross section of lead

    International Nuclear Information System (INIS)

    Kanda, K.; Aizawa, O.

    1976-01-01

    The total thermal-neutron cross section of natural lead under various physical conditions was measured by the transmission method. It became clear that the total cross section at room temperature previously reported is lower than the present data. The total cross section at 400, 500, and 600 0 C, above the melting point of lead, 327 0 C, was also measured, and the changes in the cross section as a function of temperature were examined, especially near and below the melting point. The data obtained for the randomly oriented polycrystalline state at room temperature were in reasonable agreement with the theoretical values calculated by the THRUSH and UNCLE-TOM codes

  15. Vibrational state-resolved differential cross sections for the D + H sub 2 yields DH + H reaction

    Energy Technology Data Exchange (ETDEWEB)

    Continetti, R.E.

    1989-11-01

    In this thesis, crossed-molecular-beams studies of the reaction D + H{sub 2} {yields} DH + H at collision energies of 0.53 and 1.01 eV are reported. Chapter 1 provides a survey of important experimental and theoretical studies on the dynamics of the hydrogen exchange reaction. Chapter 2 discusses the development of the excimer-laser photolysis D atom beam source that was used in these studies and preliminary experiments on the D + H{sub 2} reaction. In Chapter 3, the differential cross section measurements are presented and compared to recent theoretical predictions. The measured differential cross sections for rotationally excited DH products showed significant deviations from recent quantum scattering calculations, in the first detailed comparison of experimental and theoretical differential cross sections. These results indicate that further work on the H{sub 3} potential energy surface, particularly the bending potential, is in order.

  16. Detrended cross-correlation analysis on RMB exchange rate and Hang Seng China Enterprises Index

    Science.gov (United States)

    Ruan, Qingsong; Yang, Bingchan; Ma, Guofeng

    2017-02-01

    In this paper, we investigate the cross-correlations between the Hang Seng China Enterprises Index and RMB exchange markets on the basis of a cross-correlation statistic test and multifractal detrended cross-correlation analysis (MF-DCCA). MF-DCCA has, at best, serious limitations for most of the signals describing complex natural processes and often indicates multifractal cross-correlations when there are none. In order to prevent these false multifractal cross-correlations, we apply MFCCA to verify the cross-correlations. Qualitatively, we find that the return series of the Hang Seng China Enterprises Index and RMB exchange markets were, overall, significantly cross-correlated based on the statistical analysis. Quantitatively, we find that the cross-correlations between the stock index and RMB exchange markets were strongly multifractal, and the multifractal degree of the onshore RMB exchange markets was somewhat larger than the offshore RMB exchange markets. Moreover, we use the absolute return series to investigate and confirm the fact of multifractality. The results from the rolling windows show that the short-term cross-correlations between volatility series remain high.

  17. Temperature-dependent cross sections for meson-meson nonresonant reactions in hadronic matter

    International Nuclear Information System (INIS)

    Zhang Yiping; Xu Xiaoming; Ge Huijun

    2010-01-01

    We present a potential of which the short-distance part is given by one gluon exchange plus perturbative one- and two-loop corrections and of which the large-distance part exhibits a temperature-dependent constant value. The Schroedinger equation with this temperature-dependent potential yields a temperature dependence of the mesonic quark-antiquark relative-motion wave function and of meson masses. The temperature dependence of the potential, the wave function and the meson masses brings about temperature dependence of cross sections for the nonresonant reactions ππ→ρρ for I=2, KK→K*K* for I=1, KK*→K*K* for I=1, πK→ρK* for I=3/2, πK*→ρK* for I=3/2, ρK→ρK* for I=3/2 and πK*→ρK for I=3/2. As the temperature increases, the rise or fall of peak cross sections is determined by the increased radii of initial mesons, the loosened bound states of final mesons, and the total-mass difference of the initial and final mesons. The temperature-dependent cross sections and meson masses are parametrized.

  18. The character of resonant charge exchange involving highly excited atoms

    International Nuclear Information System (INIS)

    Kosarim, A. V.; Smirnov, B. M.; Capitelli, M.; Laricchiuta, A.

    2012-01-01

    We study the process of resonant charge exchange involving excited helium atoms with the principal quantum number n = 5 colliding with the helium ion in the ground state in the collision energy range from thermal up to 10 eV. This information may be important for the analysis of planet atmospheres containing helium, in particular, for Jupiter’s atmosphere, but our basic interest is the transition from the quantum to classical description of this process, where, due to large cross sections, evaluations of the cross sections are possible. For the chosen process, quantum theory allows determining the cross section as a result of a tunnel electron transition, while classical theory accounts for over-barrier electron transitions. The classical theory additionally requires effective transitions between states with close energies. The analysis of these transitions for helium with n = 5 shows that electron momenta and their projections are mixed for a part of the states, while for other states, the mixing is absent. A simple criterion to separate such states is given. In addition, the main contribution to the cross section of resonant charge exchange follows from tunnel electron transitions. As a result, the quantum theory is better for calculating the cross sections of resonant charge exchange than the classical one and also allows finding the partial cross sections of resonant charge exchange, while the classical approach gives the cross section of resonant charge exchange in a simple manner with the accuracy of 20%.

  19. Top quark production cross-section measurements

    CERN Document Server

    Chen, Ye; The ATLAS collaboration

    2017-01-01

    Measurements of the inclusive and differential cross-sections for top-quark pair and single top production cross sections in proton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented at center-of-mass energies of 8 TeV and 13 TeV. The inclusive measurements reach high precision and are compared to the best available theoretical calculations. These measurements, including results using boosted tops, probe our understanding of top-pair production in the TeV regime. The results are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers and NLO QCD calculations. For the t-channel single top measurement, the single top-quark and anti-top-quark total production cross-sections, their ratio, as well as differential cross sections are also presented. A measurement of the production cross-section of a single top quark in association with a W boson, the second largest single-top production mode, is also presented. Finally, measurements of ...

  20. Single Top quark production cross section and properties using the ATLAS detector at the LHC

    CERN Document Server

    ATLAS Collaboration; The ATLAS collaboration

    2015-01-01

    Measurements of single top­quark production in proton proton collisions at 7 and 8 TeV are presented. In the leading order process,​a W boson is exchanged in the t­channel. The single top­ quark and anti­top total production cross sections, their ratio, as well as a measurement of the inclusive production cross section is presented. In addition, a measurement of the production cross section of a single top quark in association with a W boson is presented. All measurements are compared to state­-of­-the­-art theoretical calculations and the CKM matrix element |Vtb| is determined. In addition, the s­-channel production is explored and limits on exotic production in single top quark processes are discussed. This includes the search for flavor changing neutral currents and the search for additional W’ bosons or a search for monotops.

  1. Differences between LASL- and ANL-processed cross sections

    International Nuclear Information System (INIS)

    Kidman, R.B.; MacFarlane, R.E.; Becker, M.

    1978-03-01

    As part of the Los Alamos Scientific Laboratory (LASL) cross-section processing development, LASL cross sections and results from MINX/1DX system are compared to the Argonne National Laboratory cross sections and results from the ETOE-2/MC 2 -2 system for a simple reactor problem. Exact perturbation theory is used to establish the eigenvalue effect of every isotope group cross-section difference. Cross sections, cross-section differences, and their eigenvalue effects are clearly and conveniently displayed and compared on a group-by-group basis

  2. (n,{alpha}) cross section measurement of gaseous sample using gridded ionization chamber. Cross section determination

    Energy Technology Data Exchange (ETDEWEB)

    Sanami, Toshiya; Baba, Mamoru; Saito, Keiichiro; Ibara, Yasutaka; Hirakawa, Naohiro [Tohoku Univ., Sendai (Japan). Faculty of Engineering

    1997-03-01

    We are developing a method of (n,{alpha}) cross section measurement using gaseous samples in a gridded ionization chamber (GIC). This method enables cross section measurements in large solid angle without the distortion by the energy loss in a sample, but requires a method to estimate the detection efficiency. We solve this problem by using GIC signals and a tight neutron collimation. The validity of this method was confirmed through the {sup 12}C(n,{alpha}{sub 0}){sup 9}Be measurement. We applied this method to the {sup 16}O(n,{alpha}){sup 13}C cross section around 14.1 MeV. (author)

  3. Dijet Cross Sections and Parton Densities in Diffractive DIS at HERA

    CERN Document Server

    Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Beckingham, M.; Begzsuren, K.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boenig, M.-O.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Cholewa, A.; Contreras, J.G.; Coughlan, J.A.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Daum, K.; Deak, M.; de Boer, Y.; Delcourt, B.; Del Degan, M.; Delvax, J.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkiewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Gayler, J.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B.R.; Grindhammer, G.; Habib, S.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Helebrant, C.; Henderson, R.C.W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Jacquet, M.; Janssen, M.E.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knutsson, A.; Korbel, V.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Li, G.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, Ll.; Martisikova, M.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G.D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Placakyte, R.; Polifka, R.; Povh, B.; Preda, T.; Prideaux, P.; Radescu, V.; Rahmat, A.J.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smiljanic, Ivan; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Staykova, Z.; Steder, M.; Stella, B.; Stiewe, J.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Tran, T.H.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tseepeldorj, B.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Utkin, D.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wissing, Ch.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

    2007-01-01

    Differential dijet cross sections in diffractive deep-inelastic scattering are measured with the H1 detector at HERA using an integrated luminosity of 51.5 pb-1. The selected events are of the type ep --> eXY, where the system X contains at least two jets and is well separated in rapidity from the low mass proton dissociation system Y. The dijet data are compared with QCD predictions at next-to-leading order based on diffractive parton distribution functions previously extracted from measurements of inclusive diffractive deep-inelastic scattering. The prediction describes the dijet data well at low and intermediate zpom (the fraction of the momentum of the diffractive exchange carried by the parton entering the hard interaction) where the gluon density is well determined from the inclusive diffractive data, supporting QCD factorisation. A new set of diffractive parton distribution functions is obtained through a simultaneous fit to the diffractive inclusive and dijet cross sections. This allows for a precise ...

  4. ZZ ELAST2, Database of Cross Sections for the Elastic Scattering of Electrons and Positrons by Atoms

    International Nuclear Information System (INIS)

    2002-01-01

    1 - Historical background and information: This database is an extension of the earlier database, 'Elastic Scattering of Electrons and Positrons by Atoms: Database ELAST', Report NISTIR 5188, 1993. Cross sections for the elastic scattering of electrons and positrons by atoms were calculated at energies from 1 KeV to 100 MeV. Up to 10 MeV the RELEL code of Riley was used. Above 10 MeV the ELSCAT code was used, which calculated the factored cross sections and evaluates the screening factor Kscr in WKB approximation. 2 - Application of the data: This database was developed to provide input for the transport codes, such as ETRAN, and includes differential cross sections, the total cross section, and the transport cross sections. In addition, a code TRANSX is provided that generates transport cross section of arbitrary order needed as input for the calculation of Goudsmit-Saunderson multiple-scattering angular distribution 3 - Source and scope of data: The database includes cross sections at 61 energies for electrons and 41 energies from positrons, covering the energy region from 1 KeV to 100 MeV. The number of deflection angles included in the database is 314 angles. Total and transport cross sections are also included in this package. The data files have an extension (jjj) that represents the atomic number of the target atom. The database includes auxiliary data files that enable the ELASTIC code to include the following optional modifications: (i) the inclusion of the exchange correction for electrons scattering; (ii) the conversion of the cross sections for scattering by free atoms to cross sections for scattering by atoms in solids; (iii) ti reduction of the cross sections at large angles and at high energies when the nucleus is treated as an extended rather than a point charge

  5. Single top quark production cross-section measurements using the ATLAS and CMS detectors at the LHC

    CERN Document Server

    Finelli, Kevin Daniel; The ATLAS collaboration

    2015-01-01

    Measurements of single top quark production in proton--proton collisions at 7 and 8 TeV using the ATLAS and CMS detectors at the LHC are presented. In the leading order process, a $W$ boson is exchanged in the $t$-channel. The single top quark and anti-top total production cross-sections ratio, as well as a measurement of the inclusive and fiducial production cross-sections are presented. In addition, a measurement of the production cross-section of a single top quark in association with a $W$ boson is presented. All measurements are compared to state-of-the-art theoretical calculations and the CKM matrix element $|V_{tb}|$ is determined. The $s$-channel production is also explored and limits on exotic production in single top quark processes are discussed. This includes the search for additional $W’$ bosons and a search for monotops.

  6. Photoionization cross section of atomic and molecular oxygen

    International Nuclear Information System (INIS)

    Pareek, P.N.

    1983-01-01

    Photoionization cross sections of atomic oxygen and dissociative photoionization cross sections of molecular oxygen were measured from their respective thresholds to 120 angstrom by use of a photoionization mass spectrometer in conjunction with a spark light source. The photoionization cross sections O 2 + parent ion and O + fragment ion from neutral O 2 were obtained by a technique that eliminated the serious problem of identifying the true abundances of O + ions. These ions are generally formed with considerable kinetic energy and, because most mass spectrometers discriminate against energetic ions, true O + abundances are difficult to obtain. In the present work the relative cross sections for producing O + ions are obtained and normalized against the total cross sections in a spectral region where dissociative ionization is not possible. The fragmentation cross sections for O + were then obtained by subtraction of O 2 + cross sections from the known total photoionization cross sections. The results are compared with the previously published measurements. The absolute photoionization cross section of atomic oxygen sigma 8 /sub +/ was measured at 304 A. The actual number density of oxygen atoms within the ionization region was obtained by measuring the fraction of 0 2 molecules dissociated. This sigma/sub +/ at 304 angstrom was used to convert the relative photoinization cross sections, measured as a function of wavelength using a calibrated photodiode, to absolute cross sections. The results are compared with previous measurements and calculated cross sections. angstrom Rydberg series converging to the OII 4 P state was observed

  7. Measurements of neutron capture cross sections

    International Nuclear Information System (INIS)

    Nakajima, Yutaka

    1984-01-01

    A review of measurement techniques for the neutron capture cross sections is presented. Sell transmission method, activation method, and prompt gamma-ray detection method are described using examples of capture cross section measurements. The capture cross section of 238 U measured by three different prompt gamma-ray detection methods (large liquid scintillator, Moxon-Rae detector, and pulse height weighting method) are compared and their discrepancies are resolved. A method how to derive the covariance is described. (author)

  8. XCOM: Photon Cross Sections Database

    Science.gov (United States)

    SRD 8 XCOM: Photon Cross Sections Database (Web, free access)   A web database is provided which can be used to calculate photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, for any element, compound or mixture (Z <= 100) at energies from 1 keV to 100 GeV.

  9. Graphs of the cross sections in the recommended Monte Carlo cross-section library at the Los Alamos Scientific Laboratory

    International Nuclear Information System (INIS)

    Soran, P.D.; Seamon, R.E.

    1980-05-01

    Graphs of all neutron cross sections and photon production cross sections on the Recommended Monte Carlo Cross Section (RMCCS) library have been plotted along with local neutron heating numbers. Values for anti ν, the average number of neutrons per fission, are also given

  10. Scattering cross section for various potential systems

    Directory of Open Access Journals (Sweden)

    Myagmarjav Odsuren

    2017-08-01

    Full Text Available We discuss the problems of scattering in this framework, and show that the applied method is very useful in the investigation of the effect of the resonance in the observed scattering cross sections. In this study, not only the scattering cross sections but also the decomposition of the scattering cross sections was computed for the α–α system. To obtain the decomposition of scattering cross sections into resonance and residual continuum terms, the complex scaled orthogonality condition model and the extended completeness relation are used. Applying the present method to the α–α and α–n systems, we obtained good reproduction of the observed phase shifts and cross sections. The decomposition into resonance and continuum terms makes clear that resonance contributions are dominant but continuum terms and their interference are not negligible. To understand the behavior of observed phase shifts and the shape of the cross sections, both resonance and continuum terms are calculated.

  11. Scattering cross section for various potential systems

    Energy Technology Data Exchange (ETDEWEB)

    Odsuren, Myagmarjav; Khuukhenkhuu, Gonchigdorj; Davaa, Suren [Nuclear Research Center, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar (Mongolia); Kato, Kiyoshi [Nuclear Reaction Data Centre, Faculty of Science, Hokkaido University, Sapporo (Japan)

    2017-08-15

    We discuss the problems of scattering in this framework, and show that the applied method is very useful in the investigation of the effect of the resonance in the observed scattering cross sections. In this study, not only the scattering cross sections but also the decomposition of the scattering cross sections was computed for the α–α system. To obtain the decomposition of scattering cross sections into resonance and residual continuum terms, the complex scaled orthogonality condition model and the extended completeness relation are used. Applying the present method to the α–α and α–n systems, we obtained good reproduction of the observed phase shifts and cross sections. The decomposition into resonance and continuum terms makes clear that resonance contributions are dominant but continuum terms and their interference are not negligible. To understand the behavior of observed phase shifts and the shape of the cross sections, both resonance and continuum terms are calculated.

  12. THEORETICAL AND EXPERIMENTAL ANALYSIS OF A CROSS-FLOW HEAT EXCHANGER

    Directory of Open Access Journals (Sweden)

    R. Tuğrul OĞULATA

    1996-03-01

    Full Text Available In this study, cross-flow plate type heat exchanger has been investigated because of its effective use in waste heat recovery systems. For this purpose, a heat regain system has been investigated and manufactured in laboratory conditions. Manufactured heat exchanger has been tested with an applicable experimental set up and temperatures, velocity of the air and the pressure losses occuring in the system have been measured and the efficiency of the system has been determined. The irreversibility of heat exchanger has been taken into consideration while the design of heat exchanger is being performed. So minimum entropy generation number has been analysied with respect to second law of thermodynamics in cross-flow heat exchanger. The minimum entropy generation number depends on parameters called optimum flow path length, dimensionless mass velocity and dimensionless heat transfer area. Variations of entropy generation number with these parameters have been analysied and introduced their graphics with their comments.

  13. Measurement of neutral current e±p cross sections at high Bjorken x with the ZEUS detector

    International Nuclear Information System (INIS)

    Abramowicz, H.; Abt, I.; Adamczyk, L.

    2013-12-01

    The neutral current e ± p cross section has been measured up to values of Bjorken x≅1 with the ZEUS detector at HERA using an integrated luminosity of 187 pb -1 of e - p and 142 pb -1 of e + p collisions at √(s)=318 GeV. Differential cross sections in x and Q 2 , the exchanged boson virtuality, are presented for Q 2 ≥725 GeV 2 . An improved reconstruction method and greatly increased amount of data allows a finer binning in the high-x region of the neutral current cross section and leads to a measurement with much improved precision compared to a similar earlier analysis. The measurements are compared to Standard Model expectations based on a variety of recent parton distribution functions.

  14. NNLO jet cross sections by subtraction

    International Nuclear Information System (INIS)

    Somogyi, G.; Bolzoni, P.; Trocsanyi, Z.

    2010-06-01

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of an earlier NNLO subtraction scheme over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state. (orig.)

  15. NNLO jet cross sections by subtraction

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, G.; Bolzoni, P. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Trocsanyi, Z. [CERN, Geneva (Switzerland)

    2010-06-15

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of an earlier NNLO subtraction scheme over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state. (orig.)

  16. NNLO jet cross sections by subtraction

    CERN Document Server

    Somogyi, Gabor; Trocsanyi, Zoltan

    2010-01-01

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of the NNLO subtraction scheme of [1-4], over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state.

  17. Differential cross sections and cross-section ratios for the electron-impact excitation of the neon 2p53s configuration

    International Nuclear Information System (INIS)

    Khakoo, M. A.; Wrkich, J.; Larsen, M.; Kleiban, G.; Kanik, I.; Trajmar, S.; Brunger, M.J.; Teubner, P.J.O.; Crowe, A.; Fontes, C.J.; Clark, R.E.H.; Zeman, V.; Bartschat, K.; Madison, D.H.; Srivastava, R.; Stauffer, A.D.

    2002-01-01

    Electron-impact differential cross-section measurements for the excitation of the 2p 5 3s configuration of Ne are reported. The Ne cross sections are obtained using experimental differential cross sections for the electron-impact excitation of the n=2 levels of atomic hydrogen [Khakoo et al., Phys. Rev. A 61, 012701-1 (1999)], and existing experimental helium differential cross-section measurements, as calibration standards. These calibration measurements were made using the method of gas mixtures (Ne and H followed by Ne and He), in which the gas beam profiles of the mixed gases are found to be the same within our experimental errors. We also present results from calculations of these differential cross sections using the R-matrix and unitarized first-order many-body theory, the distorted-wave Born approximation, and relativistic distorted-wave methods. Comparison with available experimental differential cross sections and differential cross-section ratios is also presented

  18. Capture cross sections on unstable nuclei

    Science.gov (United States)

    Tonchev, A. P.; Escher, J. E.; Scielzo, N.; Bedrossian, P.; Ilieva, R. S.; Humby, P.; Cooper, N.; Goddard, P. M.; Werner, V.; Tornow, W.; Rusev, G.; Kelley, J. H.; Pietralla, N.; Scheck, M.; Savran, D.; Löher, B.; Yates, S. W.; Crider, B. P.; Peters, E. E.; Tsoneva, N.; Goriely, S.

    2017-09-01

    Accurate neutron-capture cross sections on unstable nuclei near the line of beta stability are crucial for understanding the s-process nucleosynthesis. However, neutron-capture cross sections for short-lived radionuclides are difficult to measure due to the fact that the measurements require both highly radioactive samples and intense neutron sources. Essential ingredients for describing the γ decays following neutron capture are the γ-ray strength function and level densities. We will compare different indirect approaches for obtaining the most relevant observables that can constrain Hauser-Feshbach statistical-model calculations of capture cross sections. Specifically, we will consider photon scattering using monoenergetic and 100% linearly polarized photon beams. Challenges that exist on the path to obtaining neutron-capture cross sections for reactions on isotopes near and far from stability will be discussed.

  19. Status of neutron dosimetry cross sections

    International Nuclear Information System (INIS)

    Griffin, P.J.; Kelly, J.G.

    1992-01-01

    Several new cross section libraries, such as ENDF/B-VI(release 2), IRDF-90,JEF-2.2, and JENDL-3 Dosimetry, have recently been made available to the dosimetry community. the Sandia National Laboratories (SNL) Radiation Metrology Laboratory (RML) has worked with these libraries since pre-release versions were available. this paper summarizes the results of the intercomparison and testing of dosimetry cross sections. As a result of this analysis, a compendium of the best dosimetry cross sections was assembled from the available libraries for use within the SNL RML. this library, referred to as the SNLRML Library, contains 66 general dosimetry sensors and 3 special dosimeters unique to the RML sensor inventory. The SNLRML cross sections have been put into a format compatible with commonly used spectrum determination codes

  20. Capture cross sections on unstable nuclei

    Directory of Open Access Journals (Sweden)

    Tonchev A.P.

    2017-01-01

    Full Text Available Accurate neutron-capture cross sections on unstable nuclei near the line of beta stability are crucial for understanding the s-process nucleosynthesis. However, neutron-capture cross sections for short-lived radionuclides are difficult to measure due to the fact that the measurements require both highly radioactive samples and intense neutron sources. Essential ingredients for describing the γ decays following neutron capture are the γ-ray strength function and level densities. We will compare different indirect approaches for obtaining the most relevant observables that can constrain Hauser-Feshbach statistical-model calculations of capture cross sections. Specifically, we will consider photon scattering using monoenergetic and 100% linearly polarized photon beams. Challenges that exist on the path to obtaining neutron-capture cross sections for reactions on isotopes near and far from stability will be discussed.

  1. Graphs of the cross sections in the Alternate Monte Carlo Cross Section library at the Los Alamos Scientific Laboratory

    International Nuclear Information System (INIS)

    Seamon, R.E.; Soran, P.D.

    1980-06-01

    Graphs of all neutron cross sections and photon production cross sections on the Alternate Monte Carlo Cross Section (AMCCS) library have been plotted along with local neutron heating numbers. The values of ν-bar, the average number of neutrons per fission, are also plotted for appropriate isotopes

  2. Neutron-capture Cross Sections from Indirect Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Escher, J E; Burke, J T; Dietrich, F S; Ressler, J J; Scielzo, N D; Thompson, I J

    2011-10-18

    Cross sections for compound-nuclear reactions play an important role in models of astrophysical environments and simulations of the nuclear fuel cycle. Providing reliable cross section data remains a formidable task, and direct measurements have to be complemented by theoretical predictions and indirect methods. The surrogate nuclear reactions method provides an indirect approach for determining cross sections for reactions on unstable isotopes, which are difficult or impossible to measure otherwise. Current implementations of the method provide useful cross sections for (n,f) reactions, but need to be improved upon for applications to capture reactions.

  3. Atlas of photoneutron cross sections obtained with monoenergetic photons

    International Nuclear Information System (INIS)

    Dietrich, S.S.; Berman, B.L.

    1988-01-01

    Photoneutron cross-section and integrated cross-section data obtained with monoenergetic photons are presented in a uniform format. All of the measured partial photoneutron cross sections, the total photoneutron cross section, and the photoneutron yield cross section are plotted as functions of the incident photon energy, as are the integrated photoneutron cross sections and their first and second moments. The values of the integrated cross sections and the moments of the integrated total cross section up to the highest photon energy for which they were measured are tabulated, as are the parameters of Lorentz curves fitted to the total photoneutron cross-section data for medium and heavy nuclei (A>50). This compilation is current as of June 1987. copyright 1988 Academic Press, Inc

  4. Cross-Sectional Analysis of Longitudinal Mediation Processes.

    Science.gov (United States)

    O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

    2018-01-01

    Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

  5. Measurement of dijet cross sections for events with a leading neutron in photoproduction at HERA

    International Nuclear Information System (INIS)

    Breitweg, J.; Chekanov, S.; Derrick, M.; Krakauer, D.; Magill, S.; Musgrave, B.; Pellegrino, A.; Repond, J.; Stanek, R.; Yoshida, R.; Mattingly, M.C.K.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cara Romeo, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; De Pasquale, S.; Giusti, P.; Iacobucci, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Palmonari, F.; Pesci, A.; Sartorelli, G.; Zichichi, A.; Amelung, C.; Bornheim, A.; Brock, I.; Coboeken, K.; Crittenden, J.; Deffner, R.; Hartmann, H.; Heinloth, K.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Kappes, A.; Katz, U.F.; Kerger, R.; Paul, E.; Rautenberg, J.; Schnurbusch, H.; Stifutkin, A.; Tandler, J.; Voss, K.C.; Weber, A.; Wieber, H.; Bailey, D.S.; Barret, O.; Brook, N.H.; Foster, B.; Heath, G.P.; Heath, H.F.; Rodrigues, E.; Scott, J.; Tapper, R.J.; Capua, M.; Schioppa, M.; Susinno, G.; Jeoung, H.Y.; Kim, J.Y.; Lee, J.H.; Lim, I.T.; Ma, K.J.; Pac, M.Y.; Caldwell, A.; Liu, W.; Liu, X.; Mellado, B.; Paganis, S.; Sampson, S.; Schmidke, W.B.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Klimek, K.; Olkiewicz, K.; Piotrzkowski, K.; Przybycien, M.B.; Stopa, P.; Zawiejski, L.; Bednarek, B.; Jelen, K.; Kisielewska, D.; Kowal, A.M.; Kowalski, T.; Przybycien, M.; Rulikowska-Zarebska, E.; Suszycki, L.; Szuba, D.; Kotanski, A.; Bauerdick, L.A.T.; Behrens, U.; Bienlein, J.K.; Borras, K.; Chiochia, V.; Dannheim, D.; Desler, K.; Drews, G.; Fox-Murphy, A.; Fricke, U.; Goebel, F.; Goers, S.; Goettlicher, P.; Graciani, R.; Haas, T.; Hain, W.; Hartner, G.F.; Hebbel, K.; Hillert, S.; Koch, W.; Koetz, U.; Kowalski, H.; Labes, H.; Loehr, B.; Mankel, R.; Martens, J.; Martinez, M.; Milite, M.; Moritz, M.; Notz, D.; Petrucci, M.C.; Polini, A.; Rohde, M.; Savin, A.A.; Schneekloth, U.; Selonke, F.; Sievers, M.; Stonjek, S.; Wolf, G.; Wollmer, U.; Youngman, C.; Zeuner, W.; Coldewey, C.; Lopez-Duran Viani, A.; Meyer, A.; Schlenstedt, S.; Straub, P.B.; Barbagli, G.; Gallo, E.; Parenti, A.; Pelfer, P.G.; Bamberger, A.; Benen, A.; Coppola, N.; Eisenhardt, S.; Markun, P.; Raach, H.; Woelfle, S.; Bussey, P.J.; Bell, M.; Doyle, A.T.; Glasman, C.; Lee, S.W.; Lupi, A.; Macdonald, N.; McCance, G.J.; Saxon, D.H.; Sinclair, L.E.; Skillicorn, I.O.; Waugh, R.; Bohnet, I.; Gendner, N.; Holm, U.; Meyer-Larsen, A.; Salehi, H.; Wick, K.; Carli, T.; Garfagnini, A.; Gialas, I.; Gladilin, L.K.; Kcira, D.; Klanner, R.; Lohrmann, E.; Goncalo, R.; Long, K.R.; Miller, D.B.; Tapper, A.D.; Walker, R.; Cloth, P.; Filges, D.; Ishii, T.; Kuze, M.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Ahn, S.H.; Lee, S.B.; Park, S.K.; Lim, H.; Son, D.; Barreiro, F.; Garcia, G.; Gonzalez, O.; Labarga, L.; del Peso, J.; Redondo, I.; Terron, J.; Vazquez, M.; Barbi, M.; Corriveau, F.; Hanna, D.S.; Ochs, A.; Padhi, S.; Stairs, D.G.; Wing, M.; Tsurugai, T.; Antonov, A.; Bashkirov, V.; Danilov, M.; Dolgoshein, B.A.; Gladkov, D.; Sosnovtsev, V.; Suchkov, S.; Dementiev, R.K.; Ermolov, P.F.; Golubkov, Yu.A.; Katkov, I.I.; Khein, L.A.; Korotkova, N.A.; Korzhavina, I.A.; Kuzmin, V.A.; Lukina, O.Yu.; Proskuryakov, A.S.; Shcheglova, L.M.; Solomin, A.N.; Vlasov, N.N.; Zotkin, S.A.; Bokel, C.; Botje, M.; Bruemmer, N.; Engelen, J.; Grijpink, S.; Koffeman, E.; Kooijman, P.; Schagen, S.; van Sighem, A.; Tassi, E.; Tiecke, H.; Tuning, N.; Velthuis, J.J.; Vossebeld, J.; Wiggers, L.; de Wolf, E.; Bylsma, B.; Durkin, L.S.; Gilmore, J.; Ginsburg, C.M.; Kim, C.L.; Ling, T.Y.; Boogert, S.; Cooper-Sarkar, A.M.; Devenish, R.C.E.; Grosse-Knetter, J.; Matsushita, T.; Ruske, O.; Sutton, M.R.; Walczak, R.; Bertolin, A.; Brugnera, R.; Carlin, R.; Dal Corso, F.; Dusini, S.; Limentani, S.; Longhin, A.; Posocco, M.; Stanco, L.; Turcato, M.; Adamczyk, L.; Iannotti, L.; Oh, B.Y.; Okrasinski, J.R.; Saull, P.R.B.; Toothacker, W.S.; Whitmore, J.J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cormack, C.; Hart, J.C.; McCubbin, N.A.; Shah, T.P.; Epperson, D.; Heusch, C.; Sadrozinski, H.F.-W.; Seiden, A.; Wichmann, R.; Williams, D.C.; Park, I.H.; Pavel, N.; Abramowicz , H.; Dagan, S.; Kananov, S.; Kreisel, A.; Levy, A.; Abe, T.; Fusayasu, T.; Kohno, T.; Umemori, K.; Yamashita, T.; Hamatsu, R.; Hirose, T.; Inuzuka, M.; Kitamura, S.; Matsuzawa, K.; Nishimura, T.; Arneodo, M.; Cartiglia, N.; Cirio, R.; Costa, M.; Ferrero, M.I.; Maselli, S.; Monaco, V.; Peroni, C.; Ruspa, M.; Sacchi, R.; Solano, A.; Staiano, A.; Bailey, D.C.; Fagerstroem, C.-P.; Galea, R.; Koop, T.; Levman, G.M.; Martin, J.F.; Mirea, A.; Sabetfakhri, A.; Butterworth, J.M.; Hayes, M.E.; Heaphy, E.A.; Jones, T.W.; Lane, J.B.; West, B.J.; Ciborowski, J.; Ciesielski, R.; Grzelak, G.; Nowak, R.J.; Pawlak, J.M.; Pawlak, R.; Smalska, B.; Tymieniecka, T.; Wroblewski, A.K.; Zakrzewski, J.A.; Zarnecki, A.F.; Adamus, M.; Gadaj, T.; Deppe, O.; Eisenberg, Y.; Hochman, D.; Karshon, U.; Badgett, W.F.; Chapin, D.; Cross, R.; Foudas, C.; Mattingly, S.; Reeder, D.D.; Smith, W.H.; Vaiciulis, A.; Wildschek, T.; Wodarczyk, M.; Deshpande, A.; Dhawan, S.; Hughes, V.W.; Bhadra, S.; Catterall, C.; Cole, J.E.; Frisken, W.R.; Hall-Wilton, R.; Khakzad, M.; Menary, S.

    2001-01-01

    Differential cross sections for dijet photoproduction in association with a leading neutron using the reaction e + +p→e + +n+jet+jet+X r have been measured with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb -1 . The fraction of dijet events with a leading neutron in the final state was studied as a function of the jet kinematic variables. The cross sections were measured for jet transverse energies E T jet >6 GeV, neutron energy E n >400 GeV, and neutron production angle θ n <0.8 mrad. The data are broadly consistent with factorization of the lepton and hadron vertices and with a simple one-pion-exchange model

  6. Measurement of {sup 238}Np fission cross-section by neutrons near thermal point (preliminary results)

    Energy Technology Data Exchange (ETDEWEB)

    Abramo; vich, S.N.; Andreev, M.F.; Bol`shakov, Y.M. [Institute of Experimental Physics, Arzamas (Russian Federation)] [and others

    1995-10-01

    Measurements have been carried out of {sup 238}Np fission cross-section by thermal neutrons. The isotope {sup 238}Np was built up through the reaction {sup 238}U(p,n) on an electrostatic accelerator. Extraction and cleaning of the sample were done by ion-exchange chromatography. Fast neutrons were generated on the electrostatic accelerator through the reaction {sup 9}Be(d,n); a polyethylene block was used to slow down neutrons. Registration of fission fragments was performed with dielectric track detectors. Suggesting that the behavior of {sup 238}Np and {sup 238}U. Westscott`s factors are indentical the fission cross-section of {sup 238}Np was obtained: {sigma}{sub fo}=2110 {plus_minus} 75 barn.

  7. Parametric equations for calculation of macroscopic cross sections

    International Nuclear Information System (INIS)

    Botelho, Mario Hugo; Carvalho, Fernando

    2015-01-01

    Neutronic calculations of the core of a nuclear reactor is one thing necessary and important for the design and management of a nuclear reactor in order to prevent accidents and control the reactor efficiently as possible. To perform these calculations a library of nuclear data, including cross sections is required. Currently, to obtain a cross section computer codes are used, which require a large amount of processing time and computer memory. This paper proposes the calculation of macroscopic cross section through the development of parametric equations. The paper illustrates the proposal for the case of macroscopic cross sections of absorption (Σa), which was chosen due to its greater complexity among other cross sections. Parametric equations created enable, quick and dynamic way, the determination of absorption cross sections, enabling the use of them in calculations of reactors. The results show efficient when compared with the absorption cross sections obtained by the ALPHA 8.8.1 code. The differences between the cross sections are less than 2% for group 2 and less than 0.60% for group 1. (author)

  8. Cross-correlations between crude oil and exchange markets for selected oil rich economies

    Science.gov (United States)

    Li, Jianfeng; Lu, Xinsheng; Zhou, Ying

    2016-07-01

    Using multifractal detrended cross-correlation analysis (MF-DCCA), this paper studies the cross-correlation behavior between crude oil market and five selected exchange rate markets. The dataset covers the period of January 1,1996-December 31,2014, and contains 4,633 observations for each of the series, including daily closing prices of crude oil, Australian Dollars, Canadian Dollars, Mexican Pesos, Russian Rubles, and South African Rand. Our empirical results obtained from cross-correlation statistic and cross-correlation coefficient have confirmed the existence of cross-correlations, and the MF-DCCA results have demonstrated a strong multifractality between cross-correlated crude oil market and exchange rate markets in both short term and long term. Using rolling window analysis, we have also found the persistent cross-correlations between the exchange rates and crude oil returns, and the cross-correlation scaling exponents exhibit volatility during some time periods due to its sensitivity to sudden events.

  9. A cross-country Exchange Market Pressure (EMP dataset

    Directory of Open Access Journals (Sweden)

    Mohit Desai

    2017-06-01

    Full Text Available The data presented in this article are related to the research article titled - “An exchange market pressure measure for cross country analysis” (Patnaik et al. [1]. In this article, we present the dataset for Exchange Market Pressure values (EMP for 139 countries along with their conversion factors, ρ (rho. Exchange Market Pressure, expressed in percentage change in exchange rate, measures the change in exchange rate that would have taken place had the central bank not intervened. The conversion factor ρ can interpreted as the change in exchange rate associated with $1 billion of intervention. Estimates of conversion factor ρ allow us to calculate a monthly time series of EMP for 139 countries. Additionally, the dataset contains the 68% confidence interval (high and low values for the point estimates of ρ’s. Using the standard errors of estimates of ρ’s, we obtain one sigma intervals around mean estimates of EMP values. These values are also reported in the dataset.

  10. A cross-country Exchange Market Pressure (EMP) dataset.

    Science.gov (United States)

    Desai, Mohit; Patnaik, Ila; Felman, Joshua; Shah, Ajay

    2017-06-01

    The data presented in this article are related to the research article titled - "An exchange market pressure measure for cross country analysis" (Patnaik et al. [1]). In this article, we present the dataset for Exchange Market Pressure values (EMP) for 139 countries along with their conversion factors, ρ (rho). Exchange Market Pressure, expressed in percentage change in exchange rate, measures the change in exchange rate that would have taken place had the central bank not intervened. The conversion factor ρ can interpreted as the change in exchange rate associated with $1 billion of intervention. Estimates of conversion factor ρ allow us to calculate a monthly time series of EMP for 139 countries. Additionally, the dataset contains the 68% confidence interval (high and low values) for the point estimates of ρ 's. Using the standard errors of estimates of ρ 's, we obtain one sigma intervals around mean estimates of EMP values. These values are also reported in the dataset.

  11. Low Energy Neutrino Cross Sections

    International Nuclear Information System (INIS)

    Zeller, G.P.

    2004-01-01

    Present atmospheric and accelerator based neutrino oscillation experiments operate at low neutrino energies (Ev ∼ 1 GeV) to access the relevant regions of oscillation parameter space. As such, they require precise knowledge of the cross sections for neutrino-nucleon interactions in the sub-to-few GeV range. At these energies, neutrinos predominantly interact via quasi-elastic (QE) or single pion production processes, which historically have not been as well studied as the deep inelastic scattering reactions that dominate at higher energies.Data on low energy neutrino cross sections come mainly from bubble chamber, spark chamber, and emulsion experiments that collected their data decades ago. Despite relatively poor statistics and large neutrino flux uncertainties, these measurements provide an important and necessary constraint on Monte Carlo models in present use. The following sections discuss the current status of QE, resonant single pion, coherent pion, and single kaon production cross section measurements at low energy

  12. Comparison of the 12C(e,e'p) cross section at low momentum transfer with a relativistic calculation

    International Nuclear Information System (INIS)

    Tamae, T.; Sato, Y.; Yokokawa, T.; Asano, Y.; Kawabata, M.; Konno, O.; Nakagawa, I.; Nishikawa, I.; Hirota, K.; Yamazaki, H.; Kimura, R.; Miyase, H.; Tsubota, H.; Giusti, C.; Meucci, A.

    2009-01-01

    The (e,e ' p 0 ) cross section of 12 C has been measured at an energy transfer of 60 MeV and a momentum transfer of 104.4 MeV/c using a 197.5 MeV continuous electron beam. The cross section at missing momenta between 181.5 and 304.8 MeV/c obtained from the experiment is compared with theoretical calculations based on the relativistic distorted-wave impulse approximation with and without meson-exchange currents (MEC). The contribution of MEC due to the seagull current is large in the high-missing-momentum region, in particular for the longitudinal component. The cross sections calculated using three different current-conserving operators (cc1, cc2, and cc3) are similar, in contrast to the (γ,p) reaction, where the operators give very different results. The shape of the measured cross section is well described by the calculations, whereas its magnitude is slightly smaller than that described by the calculations.

  13. Status report on cross-sections of monitor reactions for radioisotope production

    International Nuclear Information System (INIS)

    Schwerer, O.; Okamoto, K.

    1989-12-01

    The status of data on cross-sections of 19 monitor reactions, especially for cyclotron operation, is summarized. Most of the information was extracted from the data compiled in EXFOR (EXchange FORmat) which is a common format used by the co-operating nuclear data centres in the world. The EXFOR data were supplemented by a number of additional data sets found in the literature. For each reaction a brief status summary, graphical plots of the available experimental and evaluated data, and a table of all experimental data sorted by incident particle energy, are given

  14. Group cross-section processing method and common nuclear group cross-section library based on JENDL-3 nuclear data file

    International Nuclear Information System (INIS)

    Hasegawa, Akira

    1991-01-01

    A common group cross-section library has been developed in JAERI. This system is called 'JSSTDL-295n-104γ (neutron:295 gamma:104) group constants library system', which is composed of a common 295n-104γ group cross-section library based on JENDL-3 nuclear data file and its utility codes. This system is applicable to fast and fusion reactors. In this paper, firstly outline of group cross-section processing adopted in Prof. GROUCH-G/B system is described in detail which is a common step for all group cross-section library generation. Next available group cross-section libraries developed in Japan based on JENDL-3 are briefly reviewed. Lastly newly developed JSSTDL library system is presented with some special attention to the JENDL-3 data. (author)

  15. Neutron-capture cross sections from indirect measurements

    Directory of Open Access Journals (Sweden)

    Scielzo N.D.

    2012-02-01

    Full Text Available Cross sections for compound-nuclear reactions reactions play an important role in models of astrophysical environments and simulations of the nuclear fuel cycle. Providing reliable cross section data remains a formidable task, and direct measurements have to be complemented by theoretical predictions and indirect methods. The surrogate nuclear reactions method provides an indirect approach for determining cross sections for reactions on unstable isotopes, which are difficult or impossible to measure otherwise. Current implementations of the method provide useful cross sections for (n,f reactions, but need to be improved upon for applications to capture reactions.

  16. Curves and tables of neutron cross sections

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo; Asami, Tetsuo; Yoshida, Tadashi

    1990-07-01

    Neutron cross-section curves from the Japanese Evaluated Nuclear Data Library version 3, JENDL-3, are presented in both graphical and tabular form for users in a wide range of application areas in the nuclear energy field. The contents cover cross sections for all the main reactions induced by neutrons with an energy below 20 MeV including; total, elastic scattering, capture, and fission, (n,n'), (n,2n), (n,3n), (n,α), (n,p) reactions. The 2200 m/s cross-section values, resonance integrals, and Maxwellian- and fission-spectrum averaged cross sections are also tabulated. (author)

  17. Universal law for the increase of hadronic cross sections at high energies

    International Nuclear Information System (INIS)

    Barut, A.O.; Boukraa, S.

    1987-01-01

    We show that all known total cross sections can be well described by a simple universal formula σ/sub tot/ = σ 0 +A/s/sup 1/2/+0.388 ln 2 (s/44.44) mb (s in GeV 2 ). The constant σ 0 is the same for the reactions ab and a-barb. A number of further predictions are given, and a dynamical model for the high-energy logarithmic increase is suggested. The second term is due to exchange processes

  18. Neutron Cross Sections for Aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Forsberg, Leif

    1963-08-15

    Total, elastic, inelastic, (n, 2n), (n, {alpha}), (n, p), and (n, {gamma}) cross sections for aluminium have been compiled from thermal to 100 MeV based upon literature search and theoretical interpolations and estimates. Differential elastic cross sections in the centre of mass system are represented by the Legendre coefficients. This method was chosen in order to obtain the best description of the energy dependence of the anisotropy.

  19. High ET jet cross sections at CDF

    International Nuclear Information System (INIS)

    Flaugher, B.

    1996-08-01

    The inclusive jet cross section for p anti p collisions at √s = 1.8 TeV as measured by the CDF collaboration will be presented. Preliminary CDF measurements of the Σ E T cross section at √s = 1.8 TeV and the central inclusive jet cross section at √s = 0.630 TeV will also be shown

  20. Measurement of neutral current e{sup {+-}}p cross sections at high Bjorken x with the ZEUS detector

    Energy Technology Data Exchange (ETDEWEB)

    Abramowicz, H. [Tel Aviv Univ. (Israel). School of Physics; Max-Planck-Institute for Physics, Munich (Germany); Abt, I. [Max-Planck-Institute for Physics, Munich (Germany); Adamczyk, L. [AGH-Univ. of Science and Technology, Krakow (Poland). Faculty of Physics and Applied Computer Science; Collaboration: ZEUS Collaboration; and others

    2013-12-15

    The neutral current e{sup {+-}}p cross section has been measured up to values of Bjorken x{approx_equal}1 with the ZEUS detector at HERA using an integrated luminosity of 187 pb{sup -1} of e{sup -}p and 142 pb{sup -1} of e{sup +}p collisions at {radical}(s)=318 GeV. Differential cross sections in x and Q{sup 2}, the exchanged boson virtuality, are presented for Q{sup 2}{>=}725 GeV{sup 2}. An improved reconstruction method and greatly increased amount of data allows a finer binning in the high-x region of the neutral current cross section and leads to a measurement with much improved precision compared to a similar earlier analysis. The measurements are compared to Standard Model expectations based on a variety of recent parton distribution functions.

  1. Recommended evaluation procedure for photonuclear cross section

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young-Ouk; Chang, Jonghwa; Fukahori, Tokio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    In order to generate photonuclear cross section library for the necessary applications, data evaluation is combined with theoretical evaluation, since photonuclear cross sections measured cannot provide all necessary data. This report recommends a procedure consisting of four steps: (1) analysis of experimental data, (2) data evaluation, (3) theoretical evaluation and, if necessary, (4) modification of results. In the stage of analysis, data obtained by different measurements are reprocessed through the analysis of their discrepancies to a representative data set. In the data evaluation, photonuclear absorption cross sections are evaluated via giant dipole resonance and quasi-deutron mechanism. With photoabsorption cross sections from the data evaluation, theoretical evaluation is applied to determine various decay channel cross sections and emission spectra using equilibrium and preequilibrium mechanism. After this, the calculated results are compared with measured data, and in some cases the results are modified to better describe measurements. (author)

  2. Recommended activation detector cross sections (RNDL-82)

    International Nuclear Information System (INIS)

    Bondars, Kh.Ya.; Lapenas, A.A.

    1984-01-01

    The results of the comparison between measured and calculated average cross sections in 5 benchmark experiments are presented. Calculations have been based on the data from 10 libraries of evaluated cross sections. The recommended library (RNDL-82) of the activation detector cross sections has been created on the basis of the comparison. RNDL-82, including 26 reactions, and the basic characteristics of the detectors are presented. (author)

  3. Activation cross section and isomeric cross section ratios for the (n ,2 n ) reaction on 153Eu

    Science.gov (United States)

    Luo, Junhua; Jiang, Li; Li, Suyuan

    2017-10-01

    The 153Eu(n ,2 n ) m1,m2,g152Eu cross section was measured by means of the activation technique at three neutron energies in the range 13-15 MeV. The quasimonoenergetic neutron beam was formed via the 3H(d ,n ) 4He reaction, in the Pd-300 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). The activities induced in the reaction products were measured using high-resolution γ-ray spectroscopy. The cross section of the population of the second high-spin (8-) isomeric state was measured along with the reaction cross section populating both the ground (3-) and the first isomeric state (0-). Cross sections were also evaluated theoretically using the numerical code TALYS-1.8, with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

  4. Solid oxide fuel cell power plant having a fixed contact oxidation catalyzed section of a multi-section cathode air heat exchanger

    Science.gov (United States)

    Saito, Kazuo; Lin, Yao

    2015-02-17

    The multi-section cathode air heat exchanger (102) includes at least a first heat exchanger section (104), and a fixed contact oxidation catalyzed section (126) secured adjacent each other in a stack association. Cool cathode inlet air flows through cool air channels (110) of the at least first (104) and oxidation catalyzed sections (126). Hot anode exhaust flows through hot air channels (124) of the oxidation catalyzed section (126) and is combusted therein. The combusted anode exhaust then flows through hot air channels (112) of the first section (104) of the cathode air heat exchanger (102). The cool and hot air channels (110, 112) are secured in direct heat exchange relationship with each other so that temperatures of the heat exchanger (102) do not exceed 800.degree. C. to minimize requirements for using expensive, high-temperature alloys.

  5. Activation cross section and isomeric cross-section ratio for the (n,2n) reaction on {sup 132,134}Ba

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Junhua [Hexi Univ., Zhangye (China). School of Physics and Electromechanical Engineering; Hexi Univ., Zhangye (China). Inst. of New Energy; Wu, Chunlei; Jiang, Li [Chinese Academy of Engineering Physics, Mianyang (China). Inst. of Nuclear Physics and Chemistry; Li, Suyuan [Hexi Univ., Zhangye (China). Inst. of New Energy

    2017-07-01

    Cross sections of the {sup 132}Ba(n,2n){sup 131m,g}Ba and {sup 134}Ba(n,2n){sup 133m,g}Ba reactions and their isomeric cross section ratios σ{sub m}/σ{sub g} have been measured by means of the activation technique at three neutron energies in the range 13-15 MeV. BaCO{sub 3} samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The quasimonoenergetic neutrons beam were produced via the {sup 3}H(d,n){sup 4}He reaction at the Pd-300 Neutron Generator of the Chinese Academy of Engineering Physics (CAEP). The activities induced in the reaction products were measured using high-resolution γ ray spectroscopy. The pure cross section of the ground-state was derived from the absolute cross section of the metastable state and the residual nuclear decay analysis. Cross sections were also evaluated theoretically using the numerical nuclear model code, TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

  6. Dielectronic recombination cross sections for H-like ions

    International Nuclear Information System (INIS)

    Pindzola, M.S.; Badnell, N.R.; Griffin, D.C.

    1990-01-01

    Dielectronic recombination cross sections for several H-like atomic ions are calculated in an isolated-resonance, distorted-wave approximation. Fine-structure and configuration-interaction effects are examined in detail for the O 7+ cross section. Hartree-Fock, intermediate-coupled, multiconfiguration dielectronic recombination cross sections for O 7+ are then compared with the recent experimental measurements obtained with the Test Storage Ring in Heidelberg. The cross-section spectra line up well in energy and the shape of the main resonance structures are comparable. The experimental integrated cross sections differ by up to 20% from theory, but this may be due in part to uncertainties in the electron distribution function

  7. Comparative analysis among several cross section sets

    International Nuclear Information System (INIS)

    Caldeira, A.D.

    1983-01-01

    Critical parameters were calculated using the one dimensional multigroup transport theory for several cross section sets. Calculations have been performed for water mixtures of uranium metal, plutonium metal and uranium-thorium oxide, and for metallics systems, to determine the critical dimensions of geometries (sphere and cylinder). For this aim, the following cross section sets were employed: 1) multigroup cross section sets obtained from the GAMTEC-II code; 2) the HANSEN-ROACH cross section sets; 3) cross section sets from the ENDF/B-IV, processed by the NJOY code. Finally, we have also calculated the corresponding critical radius using the one dimensional multigroup transport DTF-IV code. The numerical results agree within a few percent with the critical values obtained in the literature (where the greatest discrepancy occured in the critical dimensions of water mixtures calculated with the values generated by the NJOY code), a very good results in comparison with similar works. (Author) [pt

  8. Measurement of the cross section for diffractive deep-inelastic scattering with a leading proton at HERA

    International Nuclear Information System (INIS)

    Aaron, F.D.; Alexa, C.; Rotaru, M.; Stoicea, G.; Andreev, V.; Belousov, A.; Eliseev, A.; Fomenko, A.; Gogitidze, N.; Lebedev, A.; Loktionova, N.; Malinovski, E.; Rusakov, S.; Shtarkov, L.N.; Soloviev, Y.; Vazdik, Y.; Backovic, S.; Dubak, A.; Lastovicka-Medin, G.; Picuric, I.; Raicevic, N.; Baghdasaryan, A.; Zohrabyan, H.; Barrelet, E.; Bartel, W.; Brandt, G.; Brinkmann, M.; Britzger, D.; Campbell, A.J.; Cholewa, A.; Deak, M.; Eckerlin, G.; Elsen, E.; Felst, R.; Fischer, D.J.; Fleischer, M.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Gouzevitch, M.; Grebenyuk, A.; Grell, B.R.; Habib, S.; Haidt, D.; Helebrant, C.; Katzy, J.; Kleinwort, C.; Knutsson, A.; Kraemer, M.; Kutak, K.; Levonian, S.; Lipka, K.; List, J.; Meyer, A.B.; Meyer, J.; Niebuhr, C.; Nikiforov, A.; Nowak, K.; Olsson, J.E.; Pahl, P.; Panagoulias, I.; Papadopoulou, T.; Petrukhin, A.; Piec, S.; Pitzl, D.; Placakyte, R.; Schmitt, S.; Sefkow, F.; Staykova, Z.; Steder, M.; Toll, T.; Vargas Trevino, A.; Driesch, M. von den; Wuensch, E.; Begzsuren, K.; Ravdandorj, T.; Tseepeldorj, B.; Bizot, J.C.; Brisson, V.; Delcourt, B.; Jacquet, M.; Pascaud, C.; Tran, T.H.; Zhang, Z.; Zomer, F.; Boudry, V.; Moreau, F.; Specka, A.; Bozovic-Jelisavcic, I.; Mudrinic, M.; Pandurovic, M.; Smiljanic, I.; Bracinik, J.; Kenyon, I.R.; Newman, P.R.; Thompson, P.D.; Bruncko, D.; Cerny, V.; Ferencei, J.; Bunyatyan, A.; Buschhorn, G.; Chekelian, V.; Dossanov, A.; Grindhammer, G.; Kiesling, C.; Kogler, R.; Shushkevich, S.; Bystritskaya, L.; Efremenko, V.; Fedotov, A.; Kropivnitskaya, A.; Lubimov, V.; Ozerov, D.; Rostovtsev, A.; Zhokin, A.; Cantun Avila, K.B.; Contreras, J.G.; Ruiz Tabasco, J.E.; Ceccopieri, F.; Delvax, J.; Wolf, E.A. de; Favart, L.; Hreus, T.; Janssen, X.; Marage, P.; Mozer, M.U.; Roosen, R.; Sunar, D.; Sykora, T.; Mechelen, P. van; Cerny, K.; Pokorny, B.; Polifka, R.; Salek, D.; Valkarova, A.; Zacek, J.; Coughlan, J.A.; Morris, J.V.; Sankey, D.P.C.; Cvach, J.; Reimer, P.; Zalesak, J.; Dainton, J.B.; Gabathuler, E.; Greenshaw, T.; Klein, M.; Kluge, T.; Kretzschmar, J.; Laycock, P.; Maxfield, S.J.; Mehta, A.; Patel, G.D.; Daum, K.; Meyer, H.; Diaconu, C.; Hoffmann, D.; Sauvan, E.; Vallee, C.; Dobre, M.; List, B.; Dodonov, V.; Povh, B.; Egli, S.; Hildebrandt, M.; Horisberger, R.; Feltesse, J.; Perez, E.; Schoeffel, L.; Goerlich, L.; Mikocki, S.; Milcewicz-Mika, I.; Nowak, G.; Sopicki, P.; Turnau, J.; Grab, C.; Henderson, R.C.W.; Sloan, T.; Hennekemper, E.; Herbst, M.; Jung, A.W.; Krueger, K.; Lendermann, V.; Schultz-Coulon, H.C.; Urban, K.; Henschel, H.; Hiller, K.H.; Kostka, P.; Lange, W.; Naumann, T.; Herrera, G.; Lopez-Fernandez, R.; Huber, F.; Pirumov, H.; Radescu, V.; Sauter, M.; Schoening, A.; Joensson, L.; Osman, S.; Jung, H.; Kapichine, M.; Makankine, A.; Morozov, A.; Nikitin, D.; Palichik, V.; Spaskov, V.; Landon, M.P.J.; Rizvi, E.; Thompson, G.; Traynor, D.; Martyn, H.U.; Mueller, K.; Robmann, P.; Straumann, U.; Truoel, P.; South, D.; Wegener, D.; Stella, B.; Tsakov, I.

    2011-01-01

    The cross section for the diffractive deep-inelastic scattering process ep→eXp is measured, with the leading final state proton detected in the H1 Forward Proton Spectrometer. The data sample covers the range x P 2 in squared four-momentum transfer at the proton vertex and 4 2 2 in photon virtuality. The cross section is measured four-fold differentially in t,x P ,Q 2 and β=x/x P , where x is the Bjorken scaling variable. The t and x P dependences are interpreted in terms of an effective pomeron trajectory and a sub-leading exchange. The data are compared with perturbative QCD predictions at next-to-leading order based on diffractive parton distribution functions previously extracted from complementary measurements of inclusive diffractive deep-inelastic scattering. The ratio of the diffractive to the inclusive ep cross section is studied as a function of Q 2 ,β and x P . (orig.)

  9. Measurement of dijet cross sections for events with a leading neutron in photoproduction at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Breitweg, J.; Chekanov, S.; Derrick, M.; Krakauer, D.; Magill, S.; Musgrave, B.; Pellegrino, A.; Repond, J.; Stanek, R.; Yoshida, R.; Mattingly, M.C.K.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cara Romeo, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; De Pasquale, S.; Giusti, P.; Iacobucci, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Palmonari, F.; Pesci, A.; Sartorelli, G.; Zichichi, A.; Amelung, C.; Bornheim, A.; Brock, I.; Coboeken, K.; Crittenden, J.; Deffner, R.; Hartmann, H.; Heinloth, K.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Kappes, A.; Katz, U.F.; Kerger, R.; Paul, E.; Rautenberg, J.; Schnurbusch, H.; Stifutkin, A.; Tandler, J.; Voss, K.C.; Weber, A.; Wieber, H.; Bailey, D.S.; Barret, O.; Brook, N.H.; Foster, B. E-mail: b.foster@bristol.ac.uk; Heath, G.P.; Heath, H.F.; Rodrigues, E.; Scott, J.; Tapper, R.J.; Capua, M.; Schioppa, M.; Susinno, G.; Jeoung, H.Y.; Kim, J.Y.; Lee, J.H.; Lim, I.T.; Ma, K.J.; Pac, M.Y.; Caldwell, A.; Liu, W.; Liu, X.; Mellado, B.; Paganis, S.; Sampson, S.; Schmidke, W.B.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Klimek, K.; Olkiewicz, K.; Piotrzkowski, K.; Przybycien, M.B.; Stopa, P.; Zawiejski, L.; Bednarek, B.; Jelen, K.; Kisielewska, D.; Kowal, A.M.; Kowalski, T.; Przybycien, M.; Rulikowska-Zarebska, E.; Suszycki, L.; Szuba, D.; Kotanski, A.; Bauerdick, L.A.T.; Behrens, U.; Bienlein, J.K.; Borras, K.; Chiochia, V.; Dannheim, D.; Desler, K.; Drews, G.; Fox-Murphy, A.; Fricke, U.; Goebel, F.; Goers, S.; Goettlicher, P.; Graciani, R.; Haas, T.; Hain, W.; Hartner, G.F.; Hebbel, K.; Hillert, S.; Koch, W.; Koetz, U.; Kowalski, H.; Labes, H.; Loehr, B.; Mankel, R.; Martens, J.; Martinez, M.; Milite, M.; Moritz, M.; Notz, D.; Petrucci, M.C.; Polini, A.; Rohde, M.; Savin, A.A.; Schneekloth, U.; Selonke, F.; Sievers, M.; Stonjek, S.; Wolf, G.; Wollmer, U.; Youngman, C.; Zeuner, W.; Coldewey, C.; Lopez-Duran Viani, A.; Meyer, A.; Schlenstedt, S.[and others

    2001-02-26

    Differential cross sections for dijet photoproduction in association with a leading neutron using the reaction e{sup +}+p{yields}e{sup +}+n+jet+jet+X{sub r} have been measured with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb{sup -1}. The fraction of dijet events with a leading neutron in the final state was studied as a function of the jet kinematic variables. The cross sections were measured for jet transverse energies E{sub T}{sup jet}>6 GeV, neutron energy E{sub n}>400 GeV, and neutron production angle {theta}{sub n}<0.8 mrad. The data are broadly consistent with factorization of the lepton and hadron vertices and with a simple one-pion-exchange model.

  10. Single-Top quark production cross section and properties using the ATLAS detector at the LHC

    CERN Document Server

    Stamm, Soren; The ATLAS collaboration

    2016-01-01

    Measurements of single top-quark production in proton proton collisions at 8 TeV and 13 TeV are presented. In the leading order process, a W boson is exchanged in the t-channel. The single top-quark and anti-top total production cross sections is presented. In addition, a measurement of the production cross section of a single top quark in association with a W boson is discussed. All measurements are compared to state-of-the-art theoretical calculations and the CKM matrix element |Vtb| is determined. Finally, the first evidence for s-channel production at LHC is presented. In this analysis the signal is extracted using a maximum-likelihood fit of a discriminant which is based on the matrix element method.

  11. Fission cross section measurements at intermediate energies

    International Nuclear Information System (INIS)

    Laptev, Alexander

    2005-01-01

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

  12. Cross-modal project prioritization : a TPCB peer exchange.

    Science.gov (United States)

    2015-05-01

    This report highlights key recommendations and best practices identified at the peer exchange on Cross-Modal Project Prioritization, held on December 16 and 17, 2014, in Raleigh, North Carolina. This event was sponsored by the Transportation Planning...

  13. Systematic effects in the determination of the π N N coupling from p-barp → n-barn differential cross section

    International Nuclear Information System (INIS)

    Ericson, T.; Loiseau, B.

    1996-10-01

    It is shown that the πNN coupling constant extracted model-independently from p-barp charge exchange is subject to a systematic correction, and, more important, that the strong absorption in the critical region prevents a determination of the coupling constant to high precision using this process. This attenuates the possible conflict with the value determined from the np charge exchange cross sections. (author)

  14. Classical scattering cross section in sputtering transport theory

    International Nuclear Information System (INIS)

    Zhang Zhulin

    2002-01-01

    For Lindhard scaling interaction potential scattering commonly used in sputtering theory, the authors analyzed the great difference between Sigmund's single power and the double power cross sections calculated. The double power cross sections can give a much better approximation to the Born-Mayer scattering in the low energy region (m∼0.1). In particular, to solve the transport equations by K r -C potential interaction given by Urbassek few years ago, only the double power cross sections (m∼0.1) can yield better approximate results for the number of recoils. Therefore, the Sigmund's single power cross section might be replaced by the double power cross sections in low energy collision cascade theory

  15. Neutron scattering cross sections for 232Th and 238U inferred from proton scattering and charge exchange measurements

    International Nuclear Information System (INIS)

    Hansen, L.F.; Grimes, S.M.; Pohl, B.A.; Poppe, C.H.; Wong, C.

    1980-01-01

    Differential cross sections for the (p,n) reactions to the isobaric analog states (IAS) of 232 Th and 238 U targets were measured at 26 and 27 MeV. The analysis of the data was done in conjunction with the proton elastic and inelastic (2 + , 4 + , 6 + ) differential cross sections measured at 26 MeV. Because collective effects are important in this mass region, deformed coupled-channels calculations were carried out for the simultaneous analysis of the proton and neutron outgoing channels. The sensitivity of the calculations was studied with respect to the optical model parameters used in the calculations, the shape of the nuclear charge distribution, the type of coupling scheme assumed among the levels, the magnitude of the deformation parameters, and the magnitude of the isovector potentials, V 1 and W 1 . A Lane model-consistent analysis of the data was used to infer optical potential parameters for 6- to 7-MeV neutrons. The neutron elastic differential cross sections obtained from these calculations are compared with measurements available in the literature, and with results obtained using neutron parameters from global sets reported at these energies. 7 figures, 3 tables

  16. Cross-Market Linkages of Taiwan Index Futures Contracts Listed on the Taiwan Futures Exchange and the Singapore Exchange

    OpenAIRE

    Hung-Gay Fung; Qingfeng "Wilson" Liu; Gyoungsin "Daniel" Park

    2007-01-01

    Cointegration tests and ex ante trading rules are applied to study cross-market linkages between the Taiwan Index futures contracts listed on the Singapore Exchange and the Taiwan Stock Exchange Capitalization-weighted Stock Index futures contracts listed on the Taiwan Futures Exchange. The exchange rate-adjusted returns of the two futures series do not differ significantly in mean but in variances, and show significant mean-reverting tendencies between them. Our trading strategies are able t...

  17. Cross section data for ionization of important cyanides

    International Nuclear Information System (INIS)

    Kaur, Jaspreet; Antony, Bobby

    2015-01-01

    Highlights: • Multi centre spherical complex optical potential formalism used to find the CS. • Effective method (CSP-ic) to derive ionization contribution from inelastic CS. • Result shows excellent accord with previous results and consistent behaviour. • Maiden attempt to find CS for many cyanide molecules. • Strong correlation observed between peak of ionization with target properties. - Abstract: This article presents cross section calculations for interactions of important cyanides with electrons possessing energies beginning from ionization threshold of the target molecule to 5 keV. These data are pursued to meet the ever increasing demand for cross sections by the relevant atomic and molecular community for modelling astrophysical, atmospheric and technological domains. The calculations have been executed using an amalgam of multi centre spherical complex optical potential (MSCOP) formalism and complex scattering potential-ionization contribution (CSP-ic) method. Cross sections are compared with experimental and theoretical data wherever available. Strong correlations are observed for the cross sections which affirms consistent and reliable cross sections. Isomeric effect has been interpreted using variation of cross section with structure and target properties. Our cross sections will be tabulated in atomic collision database for use in modelling various statistical and dynamical quantities.

  18. Cross section data for ionization of important cyanides

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Jaspreet; Antony, Bobby, E-mail: bka.ism@gmail.com

    2015-11-15

    Highlights: • Multi centre spherical complex optical potential formalism used to find the CS. • Effective method (CSP-ic) to derive ionization contribution from inelastic CS. • Result shows excellent accord with previous results and consistent behaviour. • Maiden attempt to find CS for many cyanide molecules. • Strong correlation observed between peak of ionization with target properties. - Abstract: This article presents cross section calculations for interactions of important cyanides with electrons possessing energies beginning from ionization threshold of the target molecule to 5 keV. These data are pursued to meet the ever increasing demand for cross sections by the relevant atomic and molecular community for modelling astrophysical, atmospheric and technological domains. The calculations have been executed using an amalgam of multi centre spherical complex optical potential (MSCOP) formalism and complex scattering potential-ionization contribution (CSP-ic) method. Cross sections are compared with experimental and theoretical data wherever available. Strong correlations are observed for the cross sections which affirms consistent and reliable cross sections. Isomeric effect has been interpreted using variation of cross section with structure and target properties. Our cross sections will be tabulated in atomic collision database for use in modelling various statistical and dynamical quantities.

  19. Accurate Cross Sections for Microanalysis

    OpenAIRE

    Rez, Peter

    2002-01-01

    To calculate the intensity of x-ray emission in electron beam microanalysis requires a knowledge of the energy distribution of the electrons in the solid, the energy variation of the ionization cross section of the relevant subshell, the fraction of ionizations events producing x rays of interest and the absorption coefficient of the x rays on the path to the detector. The theoretical predictions and experimental data available for ionization cross sections are limited mainly to K shells of a...

  20. Comparison of local exchange potentials for electron--N2 scattering

    International Nuclear Information System (INIS)

    Rumble, J.R. Jr.; Truhlar, D.G.

    1980-01-01

    We consider vibrationally and electronically elastic electron scattering by N 2 at 2--30 eV impact energy. We consider static, static-exchange, and static--exchange-plus-polarization potentials, Cade--Sales--Wahl and INDO/1s wave functions, and semiclassical exchange and Hara free-electron--gas exchange potentials. We show that the semiclassical exchange approximation is too attractive at low energy for N 2 . We show quantitatively by consideration of partial and total integral cross sections how the effects of approximations to exchange become smaller as the incident energy is increased until these differences are about 8% for the total integral cross section at 30 eV

  1. Criticality benchmark comparisons leading to cross-section upgrades

    International Nuclear Information System (INIS)

    Alesso, H.P.; Annese, C.E.; Heinrichs, D.P.; Lloyd, W.R.; Lent, E.M.

    1993-01-01

    For several years criticality benchmark calculations with COG. COG is a point-wise Monte Carlo code developed at Lawrence Livermore National Laboratory (LLNL). It solves the Boltzmann equation for the transport of neutrons and photons. The principle consideration in developing COG was that the resulting calculation would be as accurate as the point-wise cross-sectional data, since no physics computational approximations were used. The objective of this paper is to report on COG results for criticality benchmark experiments in concert with MCNP comparisons which are resulting in corrections an upgrades to the point-wise ENDL cross-section data libraries. Benchmarking discrepancies reported here indicated difficulties in the Evaluated Nuclear Data Livermore (ENDL) cross-sections for U-238 at thermal neutron energy levels. This led to a re-evaluation and selection of the appropriate cross-section values from several cross-section sets available (ENDL, ENDF/B-V). Further cross-section upgrades anticipated

  2. Cross section homogenization analysis for a simplified Candu reactor

    International Nuclear Information System (INIS)

    Pounders, Justin; Rahnema, Farzad; Mosher, Scott; Serghiuta, Dumitru; Turinsky, Paul; Sarsour, Hisham

    2008-01-01

    The effect of using zero current (infinite medium) boundary conditions to generate bundle homogenized cross sections for a stylized half-core Candu reactor problem is examined. Homogenized cross section from infinite medium lattice calculations are compared with cross sections homogenized using the exact flux from the reference core environment. The impact of these cross section differences is quantified by generating nodal diffusion theory solutions with both sets of cross sections. It is shown that the infinite medium spatial approximation is not negligible, and that ignoring the impact of the heterogeneous core environment on cross section homogenization leads to increased errors, particularly near control elements and the core periphery. (authors)

  3. Collision cross sections and equilibrium fractions of ions and atoms in metal vapor targets. Project progress report, June 1, 1979-May 31, 1980

    International Nuclear Information System (INIS)

    Morgan, T.J.

    1980-01-01

    The objective of this program is to measure atomic collision cross sections and equilibrium fractions of ions and atoms in metal vapor targets. The goal is to obtain experimental information on atomic collision processes relevant to the Magnetic Fusion Energy Program. In particular, in connection with the development of double charge exchange D - ion sources, we are measuring D - formation cross sections in alkaline-earth metal vapor targets. During the period covered in this report we have measured electron transfer cross sections for 3-40 keV D + ions and D 0 atoms in collision with calcium vapor

  4. Fission cross section measurements of actinides at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Tovesson, Fredrik [Los Alamos National Laboratory; Laptev, Alexander B [Los Alamos National Laboratory; Hill, Tony S [INL

    2010-01-01

    Fission cross sections of a range of actinides have been measured at the Los Alamos Neutron Science Center (LANSCE) in support of nuclear energy applications. By combining measurement at two LANSCE facilities, Lujan Center and the Weapons Neutron Research center (WNR), differential cross sections can be measured from sub-thermal energies up to 200 MeV. Incident neutron energies are determined using the time-of-flight method, and parallel-plate ionization chambers are used to measure fission cross sections relative to the {sup 235}U standard. Recent measurements include the {sup 233,238}U, {sup 239,242}Pu and {sup 243}Am neutron-induced fission cross sections. In this paper preliminary results for cross section data of {sup 243}Am and {sup 233}U will be presented.

  5. Methodology series module 3: Cross-sectional studies

    Directory of Open Access Journals (Sweden)

    Maninder Singh Setia

    2016-01-01

    Full Text Available Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case–control studies (participants selected based on the outcome status or cohort studies (participants selected based on the exposure status, the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design.

  6. Methodology Series Module 3: Cross-sectional Studies.

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case-control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design.

  7. Compilation of cross-sections. Pt. 1

    International Nuclear Information System (INIS)

    Flaminio, V.; Moorhead, W.G.; Morrison, D.R.O.; Rivoire, N.

    1983-01-01

    A compilation of integral cross-sections for hadronic reactions is presented. This is an updated version of CERN/HERA 79-1, 79-2, 79-3. It contains all data published up to the beginning of 1982, but some more recent data have also been included. Plots of the cross-sections versus incident laboratory momentum are also given. (orig.)

  8. Compilation of cross-sections. Pt. 4

    International Nuclear Information System (INIS)

    Alekhin, S.I.; Ezhela, V.V.; Lugovsky, S.B.; Tolstenkov, A.N.; Yushchenko, O.P.; Baldini, A.; Cobal, M.; Flaminio, V.; Capiluppi, P.; Giacomelli, G.; Mandrioli, G.; Rossi, A.M.; Serra, P.; Moorhead, W.G.; Morrison, D.R.O.; Rivoire, N.

    1987-01-01

    This is the fourth volume in our series of data compilations on integrated cross-sections for weak, electromagnetic, and strong interaction processes. This volume covers data on reactions induced by photons, neutrinos, hyperons, and K L 0 . It contains all data published up to June 1986. Plots of the cross-sections versus incident laboratory momentum are also given. (orig.)

  9. Phenomenological extraction of two-photon exchange amplitudes from elastic electron-proton scattering cross section data

    Science.gov (United States)

    Qattan, I. A.

    2017-05-01

    Background: The inconsistency in the results obtained from the Rosenbluth separation method and the high-Q2 recoil polarization results on the ratio μpGEp/GMp implies a systematic difference between the two techniques. Several studies suggest that missing higher-order radiative corrections to elastic electron-proton scattering cross section σR(ɛ ,Q2) and in particular hard two-photon-exchange (TPE) contributions could account for the discrepancy. Purpose: In this work, I improve on and extend to low and high Q2 values the extractions of the ɛ dependence of the real parts of the TPE amplitudes relative to the magnetic form factor, as well as the ratio Pl/PlBorn(ɛ ,Q2) by using world data on σR(ɛ ,Q2) with an emphasis on precise new data covering the low-momentum region which is sensitive to the large-scale structure of the nucleon. Method: I combine cross section and polarization measurements of elastic electron-proton scattering to extract the TPE amplitudes. Because the recoil polarization data were confirmed "experimentally" to be essentially independent of ɛ , I constrain the ratio Pt/Pl(ɛ ,Q2) to its ɛ -independent term (Born value) by setting the TPE contributions to zero. This allows for the amplitude YM(ɛ ,Q2) and σR(ɛ ,Q2) to be expressed in terms of the remaining two amplitudes YE(ɛ ,Q2) and Y3(ɛ ,Q2) which in turn are parametrized as second-order polynomials in ɛ and Q2 to reserve as possible the linearity of σR(ɛ ,Q2) as well as to account for possible nonlinearities in the TPE amplitudes. Furthermore, I impose the Regge limit which ensures the vanishing of the TPE contributions to σR(ɛ ,Q2) and the TPE amplitudes in the limit ɛ →1 . Results: I provide simple parametrizations of the TPE amplitudes, along with an estimate of the fit uncertainties. The extracted TPE amplitudes are compared with previous phenomenological extractions and TPE calculations. The Pl/PlBorn ratio is extracted by using the new parametrizations of the TPE

  10. Evaluation of fusion-evaporation cross-section calculations

    Science.gov (United States)

    Blank, B.; Canchel, G.; Seis, F.; Delahaye, P.

    2018-02-01

    Calculated fusion-evaporation cross sections from five different codes are compared to experimental data. The present comparison extents over a large range of nuclei and isotopic chains to investigate the evolution of experimental and calculated cross sections. All models more or less overestimate the experimental cross sections. We found reasonable agreement by using the geometrical average of the five model calculations and dividing the average by a factor of 11.2. More refined analyses are made for example for the 100Sn region.

  11. NDS multigroup cross section libraries

    International Nuclear Information System (INIS)

    DayDay, N.

    1981-12-01

    A summary description and documentation of the multigroup cross section libraries which exist at the IAEA Nuclear Data Section are given in this report. The libraries listed are available either on tape or in printed form. (author)

  12. Gluon exchange in elastic hadron scattering

    International Nuclear Information System (INIS)

    Jenkovszky, L.L.; Paccanoni, F.; Chikovani, Z.E.

    1991-01-01

    It is generally accepted that the Pomeron, which determines the long-range component of the strong interaction, corresponds to exchange of gluons with the corresponding quantum numbers (the minimum number of such gluons is two). The C-odd partner of the Pomeron, the odderon, corresponds to exchange of an odd number of gluons (three or more). By means of a model of the nonperturbative gluon propagator, restrictions are obtained on the parameters of two-gluon (Pomeron) and three-gluon (odderon) exchange in hadron scattering. In the framework of this model an interpretation is proposed for the various asymptotic regimes in the behavior of the total cross section and of the differential cross section of elastic scattering at high energies

  13. Neutron-induced fission cross sections

    International Nuclear Information System (INIS)

    Weigmann, H.

    1991-01-01

    In the history of fission research, neutron-induced fission has always played the most important role. The practical importance of neutron-induced fission rests upon the fact that additional neutrons are produced in the fission process, and thus a chain reaction becomes possible. The practical applications of neutron-induced fission will not be discussed in this chapter, but only the physical properties of one of its characteristics, namely (n,f) cross sections. The most important early summaries on the subject are the monograph edited by Michaudon which also deals with the practical applications, the earlier review article on fission by Michaudon, and the review by Bjornholm and Lynn, in which neutron-induced fission receives major attention. This chapter will attempt to go an intermediate way between the very detailed theoretical treatment in the latter review and the cited monograph which emphasizes the applied aspects and the techniques of fission cross-section measurements. The more recent investigations in the field will be included. Section II will survey the properties of cross sections for neutron-induced fission and also address some special aspects of the experimental methods applied in their measurement. Section Ill will deal with the formal theory of neutron-induced nuclear reactions for the resolved resonance region and the region of statistical nuclear reactions. In Section IV, the fission width, or fission transmission coefficient, will be discussed in detail. Section V will deal with the broader structures due to incompletely damped vibrational resonances, and in particular will address the special case of thorium and neighboring isotopes. Finally, Section VI will briefly discuss parity violation effects in neutron-induced fission. 74 refs., 14 figs., 3 tabs

  14. ENDF/B-5 fission product cross section evaluations

    International Nuclear Information System (INIS)

    Schenter, R.E.; England, T.R.

    1979-12-01

    Cross section evaluations were made for the 196 fission product nuclides on the ENDF/B-5 data files. Most of the evaluations involve updating the capture cross sections of the important absorbers for fast and thermal reactor systems. This included updating thermal values, resonance integrals, resonance parameter sets, and fast capture cross sections. For the fast capture results generalized least-squares calculations were made with the computer code FERRET. Input for these cross section adjustments included nuclear models calculations and both integral and differential experimental data results. The differential cross sections and their uncertainties were obtained from the CSIRS library. Integral measurement results came from CFRMF and STEK Assemblies 500, 1000, 2000, 3000, 4000. Comparisons of these evaluations with recent capture measurements are shown. 15 figures, 10 tables

  15. Nuclear fission and neutron-induced fission cross-sections

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-01-01

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

  16. Model cross section calculations using LAHET

    International Nuclear Information System (INIS)

    Prael, R.E.

    1992-01-01

    The current status of LAHET is discussed. The effect of a multistage preequilibrium exciton model following the INC is examined for neutron emission benchmark calculations, as is the use of a Fermi breakup model for light nuclei rather than an evaporation model. Comparisons are made also for recent fission cross section experiments, and a discussion of helium production cross sections is presented

  17. Interference analysis of fission cross section

    International Nuclear Information System (INIS)

    Toshkov, S.A.; Yaneva, N.B.

    1976-01-01

    The formula for the reaction cross-section based on the R-matrix formalism considering the interference between the two neighbouring resonances, referred to the same value of total momentum was used for the analysis of the cross-section of resonance neutron induced fission of 230Pu. The experimental resolution and thermal motion of the target nuclei were accounted for numerical integration

  18. Total cross sections for electron scattering by He

    International Nuclear Information System (INIS)

    De Heer, F.J.; Jansen, R.H.J.

    1977-01-01

    A set of total cross sections for scattering of electrons by He has been evaluated over the energy range of zero to 3000 eV by means of the analysis of experiments and theories on total cross sections for elastic scattering, ionisation and excitation, and on differential cross sections for elastic and inelastic scattering. Between 0 and 19.8 eV, where no inelastic processes occur, the total cross sections for scattering are equal to those for elastic scattering. Above 19.8 eV total cross sections for scattering of electrons have been evaluated by adding those for ionisation, excitation and elastic scattering. The total cross sections thus obtained are probably accurate to about 5% over a large part of the energy range. They appear to be in very good agreement with the recent experimental results of Blaauw et al. (J. Phys. B.; 10:L299 (1977)). The present results have already proved useful for application in the dispersion relation for forward scattering in electron-helium collisions. (author)

  19. Cross Sections for Inner-Shell Ionization by Electron Impact

    Energy Technology Data Exchange (ETDEWEB)

    Llovet, Xavier, E-mail: xavier@ccit.ub.edu [Centres Científics i Tecnològics, Universitat de Barcelona, Lluís Solé i Sabarís 1-3, 08028 Barcelona (Spain); Powell, Cedric J. [Materials Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8370 (United States); Salvat, Francesc [Facultat de Física (ECM and ICC), Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain); Jablonski, Aleksander [Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw (Poland)

    2014-03-15

    An analysis is presented of measured and calculated cross sections for inner-shell ionization by electron impact. We describe the essentials of classical and semiclassical models and of quantum approximations for computing ionization cross sections. The emphasis is on the recent formulation of the distorted-wave Born approximation by Bote and Salvat [Phys. Rev. A 77, 042701 (2008)] that has been used to generate an extensive database of cross sections for the ionization of the K shell and the L and M subshells of all elements from hydrogen to einsteinium (Z = 1 to Z = 99) by electrons and positrons with kinetic energies up to 1 GeV. We describe a systematic method for evaluating cross sections for emission of x rays and Auger electrons based on atomic transition probabilities from the Evaluated Atomic Data Library of Perkins et al. [Lawrence Livermore National Laboratory, UCRL-ID-50400, 1991]. We made an extensive comparison of measured K-shell, L-subshell, and M-subshell ionization cross sections and of Lα x-ray production cross sections with the corresponding calculated cross sections. We identified elements for which there were at least three (for K shells) or two (for L and M subshells) mutually consistent sets of cross-section measurements and for which the cross sections varied with energy as expected by theory. The overall average root-mean-square deviation between the measured and calculated cross sections was 10.9% and the overall average deviation was −2.5%. This degree of agreement between measured and calculated ionization and x-ray production cross sections was considered to be very satisfactory given the difficulties of these measurements.

  20. Floodplain Cross Section Lines

    Data.gov (United States)

    Department of Homeland Security — This table is required for any Digital Flood Insurance Rate Map database where cross sections are shown on the Flood Insurance Rate Map (FIRM). Normally any FIRM...

  1. A Pebble Bed Reactor cross section methodology

    International Nuclear Information System (INIS)

    Hudson, Nathanael H.; Ougouag, Abderrafi M.; Rahnema, Farzad; Gougar, Hans

    2009-01-01

    A method is presented for the evaluation of microscopic cross sections for the Pebble Bed Reactor (PBR) neutron diffusion computational models during convergence to an equilibrium (asymptotic) fuel cycle. This method considers the isotopics within a core spectral zone and the leakages from such a zone as they arise during reactor operation. The randomness of the spatial distribution of fuel grains within the fuel pebbles and that of the fuel and moderator pebbles within the core, the double heterogeneity of the fuel, and the indeterminate burnup of the spectral zones all pose a unique challenge for the computation of the local microscopic cross sections. As prior knowledge of the equilibrium composition and leakage is not available, it is necessary to repeatedly re-compute the group constants with updated zone information. A method is presented to account for local spectral zone composition and leakage effects without resorting to frequent spectrum code calls. Fine group data are pre-computed for a range of isotopic states. Microscopic cross sections and zone nuclide number densities are used to construct fine group macroscopic cross sections, which, together with fission spectra, flux modulation factors, and zone buckling, are used in the solution of the slowing down balance to generate a new or updated spectrum. The microscopic cross-sections are then re-collapsed with the new spectrum for the local spectral zone. This technique is named the Spectral History Correction (SHC) method. It is found that this method accurately recalculates local broad group microscopic cross sections. Significant improvement in the core eigenvalue, flux, and power peaking factor is observed when the local cross sections are corrected for the effects of the spectral zone composition and leakage in two-dimensional PBR test problems.

  2. Transport cross section for small-angle scattering

    International Nuclear Information System (INIS)

    D'yakonov, M.I.; Khaetskii, A.V.

    1991-01-01

    Classical mechanics is valid for describing potential scattering under the conditions (1) λ much-lt α and (2) U much-gt ℎυ/α, where λ is the de Broglie wavelength, α is the characteristic size of the scatterer, U is the characteristic value of the potential energy, and υ is the velocity of the scattered particle. The second of these conditions means that the typical value of the classical scattering angle is far larger than the diffraction angle λ/α. In this paper the authors show that this second condition need not hold in a derivation of the transport cross section. In other words, provided that the condition λ much-lt α holds, it is always possible to calculate the transport cross section from the expressions of classical mechanics, even in the region U approx-lt ℎυ/α, where the scattering is diffractive,and the differential cross section is greatly different from the classical cross section. The transport cross section is found from the classical expression even in the anticlassical case U much-lt ℎυ/α, where the Born approximation can be used

  3. Total scattering cross sections and interatomic potentials for neutral hydrogen and helium on some noble gases

    International Nuclear Information System (INIS)

    Ruzic, D.N.; Cohen, S.A.

    1985-04-01

    Measurements of energy-dependent scattering cross sections for 30 to 1800 eV D incident on He, Ne, Ar, and Kr, and for 40 to 850 eV He incident on He, Ar, and Kr are presented. They are determined by using the charge-exchange efflux from the Princeton Large Torus tokamak as a source of D or He. These neutrals are passed through a gas-filled scattering cell and detected by a time-of-flight spectrometer. The cross section for scattering greater than the effective angle of the apparatus (approx. =20 mrad) is found by measuring the energy-dependent attenuation of D or He as a function of pressure in the scattering cell. The interatomic potential is extracted from the data

  4. Nonelastic-scattering cross sections of elemental nickel

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.; Whalen, J.F.

    1980-06-01

    Neutron total cross sections of elemental nickel were measured from 1.3 to 4.5 MeV, at intervals of approx. 50 keV, with resolutions of 30 to 50 keV and to accuracies of 1 to 2.5%. Neutron differential-elastic-scattering cross sections were measured from 1.45 to 3.8 MeV, at intervals and with resolutions comparable to those of the total cross sections, and to accuracies of 3 to 5%. The nonelastic-scattering cross section is derived from the measured values to accuracies of greater than or equal to 6%. The experimental results are compared with previously reported values as represented by ENDF/B-V, and areas of consistency and discrepancy, noted. The measured results are shown to be in good agreement with the predictions of a model previously reported by the authors. 4 figures, 1 table

  5. Fragmentation cross sections outside the limiting-fragmentation regime

    CERN Document Server

    Sümmerer, K

    2003-01-01

    The empirical parametrization of fragmentation cross sections, EPAX, has been successfully applied to estimate fragment production cross sections in reactions of heavy ions at high incident energies. It is checked whether a similar parametrization can be found for proton-induced spallation around 1 GeV, the range of interest for ISOL-type RIB facilities. The validity of EPAX for medium-energy heavy-ion induced reactions is also checked. Only a few datasets are available, but in general EPAX predicts the cross sections rather well, except for fragments close to the projectile, where the experimental cross sections are found to be larger.

  6. Measurements of fission cross-sections. Chapter 4

    International Nuclear Information System (INIS)

    James, G.D.

    1981-01-01

    The steps involved in the measurement of fission cross sections are summarized and the range of techniques available are considered. Methods of fission detection are described with particular emphasis on the neutron energy dependent properties of the fission process and the details of fragment energy loss which can lead to energy-dependent changes in detector efficiency. Selected examples of fission cross-section measurements are presented and methods of data reduction, storage, analysis and evaluation, are examined. Finally requested accuracies for fission cross section data are compared to estimated available accuracies. (U.K.)

  7. Vibrational enhancement of total breakup cross sections

    International Nuclear Information System (INIS)

    Haftel, M.I.; Lim, T.K.

    1984-01-01

    This paper considers the role of multi-two-body bound states, namely vibrational excitations, on total three-body breakup cross-sections. Total cross-sections are usually easy to measure, and they play a fundamental role in chemical kinetics. (orig.)

  8. Target dependence of K+-nucleus total cross sections

    International Nuclear Information System (INIS)

    Jiang, M.F.; Ernst, D.J.; Chen, C.M.

    1995-01-01

    We investigate the total cross section and its target dependence for K + -nucleus scattering using a relativistic momentum-space optical potential model which incorporates relativistically normalized wave functions, invariant two-body amplitudes, covariant kinematics, and an exact full-Fermi averaging integral. The definition of the total cross section in the presence of a Coulomb interaction is reviewed and the total cross section is calculated in a way that is consistent with what is extracted from experiment. In addition, the total cross sections for a nucleus and for the deuteron are calculated utilizing the same theory. This minimizes the dependence of the ratio of these cross sections on the details of the theory. The model dependence of the first-order optical potential calculations is investigated. The theoretical results are found to be systematically below all existing data

  9. Tables of RCN-2 fission-product cross section evaluation

    International Nuclear Information System (INIS)

    Gruppelaar, H.

    1979-05-01

    This report (continuation of ECN-13 and ECN-33) describes the third part of the RCN-2 evaluation of neutron cross sections for fission product nuclides in KEDAK format. It contains evaluated data for nine nuclides, i.e. 142 Nd, 143 Nd, 144 Nd, 145 Nd, 146 Nd, 147 Nd, 148 Nd, 150 Nd and 147 Pm. Most emphasis has been given to the evaluation of the radiative capture cross section, in order to provide a data base for adjustment calculations using results of integral measurements. Short evaluation reports are given for this cross section. The evaluated capture cross sections are compared with recent experimental differential and integral data. Graphs are given of the capture cross sections at neutron energies above 1 keV, in which also adjusted point cross sections, based upon integral STEK and CFRMF data have been plotted. Moreover, the results are compared with those of the well-known ENDF/B-IV evaluation for fission product nucleides. Finally, evaluation summaries are given, which include tables of other important neutron cross sections, such as the total, elastic scattering and inelastic scattering cross sections

  10. Microscopic cross sections: An utopia?

    Energy Technology Data Exchange (ETDEWEB)

    Hilaire, S. [CEA Bruyeres-le-Chatel, DIF 91 (France); Koning, A.J. [Nuclear Research and Consultancy Group, PO Box 25, 1755 ZG Petten (Netherlands); Goriely, S. [Institut d' Astronomie et d' Astrophysique, Universite Libre de Bruxelles, Campus de la Plaine, CP 226, 1050 Brussels (Belgium)

    2010-07-01

    The increasing need for cross sections far from the valley of stability poses a challenge for nuclear reaction models. So far, predictions of cross sections have relied on more or less phenomenological approaches, depending on parameters adjusted to available experimental data or deduced from systematical relations. While such predictions are expected to be reliable for nuclei not too far from the experimentally known regions, it is clearly preferable to use more fundamental approaches, based on sound physical bases, when dealing with very exotic nuclei. Thanks to the high computer power available today, all major ingredients required to model a nuclear reaction can now be (and have been) microscopically (or semi-microscopically) determined starting from the information provided by a nucleon-nucleon effective interaction. We have implemented all these microscopic ingredients in the TALYS nuclear reaction code, and we are now almost able to perform fully microscopic cross section calculations. The quality of these ingredients and the impact of using them instead of the usually adopted phenomenological parameters will be discussed. (authors)

  11. Microscopic cross sections: An utopia?

    International Nuclear Information System (INIS)

    Hilaire, S.; Koning, A.J.; Goriely, S.

    2010-01-01

    The increasing need for cross sections far from the valley of stability poses a challenge for nuclear reaction models. So far, predictions of cross sections have relied on more or less phenomenological approaches, depending on parameters adjusted to available experimental data or deduced from systematical relations.While such predictions are expected to be reliable for nuclei not too far from the experimentally known regions, it is clearly preferable to use more fundamental approaches, based on sound physical bases, when dealing with very exotic nuclei. Thanks to the high computer power available today, all major ingredients required to model a nuclear reaction can now be (and have been) microscopically (or semi-microscopically) determined starting from the information provided by a nucleon-nucleon effective interaction. We have implemented all these microscopic ingredients in the TALYS nuclear reaction code, and we are now almost able to perform fully microscopic cross section calculations. The quality of these ingredients and the impact of using them instead of the usually adopted phenomenological parameters will be discussed. (authors)

  12. Multilevel parametrization of fissile nuclei resonance cross sections

    International Nuclear Information System (INIS)

    Lukyanov, A.A.; Kolesov, V.V.; Janeva, N.

    1987-01-01

    Because the resonance interference has an important influence on the resonance structure of neutron cross sections energy dependence at lowest energies, multilevel scheme of the cross section parametrization which take into account the resonance interference is used for the description with the same provisions in the regions of the interferential maximum and minimum of the resonance cross sections of the fissile nuclei

  13. Total and ionization cross sections of electron scattering by fluorocarbons

    International Nuclear Information System (INIS)

    Antony, B K; Joshipura, K N; Mason, N J

    2005-01-01

    Electron impact total cross sections (50-2000 eV) and total ionization cross sections (threshold to 2000 eV) are calculated for typical plasma etching molecules CF 4 , C 2 F 4 , C 2 F 6 , C 3 F 8 and CF 3 I and the CF x (x 1-3) radicals. The total elastic and inelastic cross sections are determined in the spherical complex potential formalism. The sum of the two gives the total cross section and the total inelastic cross section is used to calculate the total ionization cross sections. The present total and ionization cross sections are found to be consistent with other theories and experimental measurements, where they exist. Our total cross section results for CF x (x = 1-3) radicals presented here are first estimates on these species

  14. Calculation of atom displacement cross section for structure material

    International Nuclear Information System (INIS)

    Liu Ping; Xu Yiping

    2015-01-01

    The neutron radiation damage in material is an important consideration of the reactor design. The radiation damage of materials mainly comes from atom displacements of crystal structure materials. The reaction cross sections of charged particles, cross sections of displacements per atom (DPA) and KERMA are the basis of radiation damage calculation. In order to study the differences of DPA cross sections with different codes and different evaluated nuclear data libraries, the DPA cross sections for structure materials were calculated with UNF and NJOY codes, and the comparisons of results were given. The DPA cross sections from different evaluated nuclear data libraries were compared. And the comparison of DPA cross sections between NJOY and Monte Carlo codes was also done. The results show that the differences among these evaluated nuclear data libraries exist. (authors)

  15. Preparation of next generation set of group cross sections. 3

    International Nuclear Information System (INIS)

    Kaneko, Kunio

    2002-03-01

    This fiscal year, based on the examination result about the evaluation energy range of heavy element unresolved resonance cross sections, the upper energy limit of the energy range, where ultra-fine group cross sections are produced, was raised to 50 keV, and an improvement of the group cross section processing system was promoted. At the same time, reflecting the result of studies carried out till now, a function producing delayed neutron data was added to the general-purpose group cross section processing system , thus the preparation of general purpose group cross section processing system has been completed. On the other hand, the energy structure, data constitution and data contents of next generation group cross section set were determined, and the specification of a 151 groups next generation group cross section set was defined. Based on the above specification, a concrete library format of the next generation cross section set has been determined. After having carried out the above-described work, using the general-purpose group cross section processing system , which was complete in this study, with use of the JENDL-3. 2 evaluated nuclear data, the 151 groups next generation group cross section of 92 nuclides and the ultra fine group resonance cross section library for 29 nuclides have been prepared. Utilizing the 151 groups next generation group cross section set and the ultra-fine group resonance cross-section library, a bench mark test calculation of fast reactors has been performed by using an advanced lattice calculation code. It was confirmed, by comparing the calculation result with a calculation result of continuous energy Monte Carlo code, that the 151 groups next generation cross section set has sufficient accuracy. (author)

  16. Positive Scattering Cross Sections using Constrained Least Squares

    International Nuclear Information System (INIS)

    Dahl, J.A.; Ganapol, B.D.; Morel, J.E.

    1999-01-01

    A method which creates a positive Legendre expansion from truncated Legendre cross section libraries is presented. The cross section moments of order two and greater are modified by a constrained least squares algorithm, subject to the constraints that the zeroth and first moments remain constant, and that the standard discrete ordinate scattering matrix is positive. A method using the maximum entropy representation of the cross section which reduces the error of these modified moments is also presented. These methods are implemented in PARTISN, and numerical results from a transport calculation using highly anisotropic scattering cross sections with the exponential discontinuous spatial scheme is presented

  17. Heisenberg rise of total cross sections

    International Nuclear Information System (INIS)

    Ezhela, V.V.; Yushchenko, O.P.

    1988-01-01

    It is shown that on the basis of the original idea of Heisenberg on the quasiclassical picture of extended particle interactions one can construct a satisfactory description of the total cross sections, elastic cross sections, elastic diffractive slopes and mean charged multiplicities in the cm energy range from 5 to 900 GeV, and produce reasonable extrapolations up to several tens of TeV. 14 refs.; 7 figs.; 2 tabs

  18. FENDL/E-2.0. Evaluated nuclear data library of neutron-nucleus interaction cross sections and photon production cross sections and photon-atom interaction cross sections for fusion applications. Version 1, March 1997. Summary documentation

    International Nuclear Information System (INIS)

    Pashchenko, A.B.; Wienke, H.

    1998-01-01

    This document presents the description of a physical tape containing the basic evaluated nuclear data library of neutron-nucleus interaction cross sections, photon production cross sections and photon-atom interaction cross sections for fusion applications. It is part of the evaluated nuclear data library for fusion applications FENDL-2. The data are available cost-free from the Nuclear Data Section upon request. The data can also be retrieved by the user via online access through international computer networks. (author)

  19. Measurement of the diffractive deep-inelastic scattering cross section with a leading proton at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Aaron, F.D. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Bucharest Univ. (Romania). Faculty of Physics; Alexa, C. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Andreev, V. [Lebedev Physical Institute, Moscow (RU)] (and others)

    2010-06-15

    The cross section for the diffractive deep-inelastic scattering process ep{yields}eXp is measured, with the leading final state proton detected in the H1 Forward Proton Spectrometer. The data sample covers the range x{sub P} < 0.1 in fractional proton longitudinal momentum loss, 0.1< vertical stroke t vertical stroke <0.7 GeV{sup 2} in squared four-momentum transfer at the proton vertex and 4cross section is measured four-fold differentially in t, x{sub P},Q{sup 2} and {beta}=x/x{sub P}, where x is the Bjorken scaling variable. The t and x{sub P} dependences are interpreted in terms of an effective pomeron trajectory and a sub-leading exchange. The data are compared to perturbative QCD predictions at next-to-leading order based on diffractive parton distribution functions previously extracted from complementary measurements of inclusive diffractive deep-inelastic scattering. The ratio of the diffractive to the inclusive ep cross section is studied as a function of Q{sup 2}, {beta} and x{sub P}. (orig.)

  20. Covalently cross-linked polyetheretherketone proton exchange membrane for DMFC

    CSIR Research Space (South Africa)

    Luo, H

    2009-05-01

    Full Text Available -7 cm2/s) and good electrochemical stability. The results suggested that cross-linked polyetheretherketone membrane is particularly promising to be used as proton exchange membrane for the direct methanol fuel cell application....

  1. Quantitative analysis of the fusion cross sections using different microscopic nucleus-nucleus interactions

    Energy Technology Data Exchange (ETDEWEB)

    Adel, A. [Cairo University, Physics Department, Faculty of Science, Giza (Egypt); Majmaah University, Physics Department, College of Science, Al-Zulfi (Saudi Arabia); Alharbi, T. [Majmaah University, Physics Department, College of Science, Al-Zulfi (Saudi Arabia)

    2017-01-15

    The fusion cross sections for reactions involving medium and heavy nucleus-nucleus systems are investigated near and above the Coulomb barrier using the one-dimensional barrier penetration model. The microscopic nuclear interaction potential is computed by four methods, namely: the double-folding model based on a realistic density-dependent M3Y NN interaction with a finite-range exchange part, the Skyrme energy density functional in the semiclassical extended Thomas-Fermi approximation, the generalized Proximity potential, and the Akyuez-Winther interaction. The comparison between the calculated and the measured values of the fusion excitation functions indicates that the calculations of the DFM give quite satisfactory agreement with the experimental data, being much better than the other methods. New parameterized forms for the fusion barrier heights and positions are presented. Furthermore, the effects of deformation and orientation degrees of freedom on the distribution of the Coulomb barrier characteristics as well as the fusion cross sections are studied for the reactions {sup 16}O + {sup 70}Ge and {sup 28}Si + {sup 100}Mo. The calculated values of the total fusion cross sections are compared with coupled channel calculations using the code CCFULL and compared with the experimental data. Our results reveal that the inclusion of deformations and orientation degrees of freedom improves the comparison with the experimental data. (orig.)

  2. Modelisation of the fission cross section

    International Nuclear Information System (INIS)

    Morariu, Claudia

    2013-03-01

    The neutron cross sections of four nuclear systems (n+ 235 U, n+ 233 U, n+ 241 Am and n+ 237 Np) are studied in the present document. The target nuclei of the first case, like 235 U and 239 Pu, have a large fission cross section after the absorption of thermal neutrons. These nuclei are called 'fissile' nuclei. The other type of nuclei, like 237 Np and 241 Am, fission mostly with fast neutrons, which exceed the fission threshold energy. These types of nuclei are called 'fertile'. The compound nuclei of the fertile nuclei have a binding energy higher than the fission barrier, while for the fissile nuclei the binding energy is lower than the fission barrier. In this work, the neutron induced cross sections for both types of nuclei are evaluated in the fast energy range. The total, reaction and shape-elastic cross sections are calculated by the coupled channel method of the optical model code ECIS, while the compound nucleus mechanism are treated by the statistical models implemented in the codes STATIS, GNASH and TALYS. The STATIS code includes a refined model of the fission process. Results from the theoretical calculations are compared with data retrieved from the experimental data base EXFOR. (author) [fr

  3. Cross sections for hadron and lepton production processes

    International Nuclear Information System (INIS)

    Bhattacharya, R.

    1976-01-01

    Charged heavy lepton production in proton-proton collisions is studied. Motivated by recent experimental results from the Stanford Linear Accelerator Center a parton model analysis is given of the reaction p + p → L + + L - + x → μ +- + e/ -+ / + neutrinos + x. Results are presented for the total cross section and the differential cross sections with respect to the invariant mass squared of the final charged leptons and the transverse momenta of each one of them. The two-photon mechanism for pair production in colliding beam exeriments is considered. Through the use of mapped invariant integration variables, a reliable exact numerical calculation of the cross section for the production of muon and pion pairs by the two-photon mechanism is provided. Results are given for the exact total cross sections and also the differential cross sections with respect to the invariant mass squared of the pair. These are compared to the results obtained from the equivalent photon approximation method

  4. Total reaction cross sections and neutron-removal cross sections of neutron-rich light nuclei measured by the COMBAS fragment-separator

    Science.gov (United States)

    Hue, B. M.; Isataev, T.; Erdemchimeg, B.; Artukh, A. G.; Aznabaev, D.; Davaa, S.; Klygin, S. A.; Kononenko, G. A.; Khuukhenkhuu, G.; Kuterbekov, K.; Lukyanov, S. M.; Mikhailova, T. I.; Maslov, V. A.; Mendibaev, K.; Sereda, Yu M.; Penionzhkevich, Yu E.; Vorontsov, A. N.

    2017-12-01

    Preliminary results of measurements of the total reaction cross sections σR and neutron removal cross section σ-xn for weakly bound 6He, 8Li, 9Be and 10Be nuclei at energy range (20-35) A MeV with 28Si target is presented. The secondary beams of light nuclei were produced by bombardment of the 22Ne (35 A MeV) primary beam on Be target and separated by COMBAS fragment-separator. In dispersive focal plane a horizontal slit defined the momentum acceptance as 1% and a wedge degrader of 200 μm Al was installed. The Bρ of the second section of the fragment-separator was adjusted for measurements in energy range (20-35) A MeV. Two-neutron removal cross sections for 6He and 10Be and one -neutron removal cross sections 8Li and 9Be were measured.

  5. Microscopic cross-section measurements by thermal neutron activation

    International Nuclear Information System (INIS)

    Avila L, J.

    1987-08-01

    Microscopic cross sections measured by thermal neutron activation using RP-0 reactor at the Peruvian Nuclear Energy Institute. The method consists in measuring microscopic cross section ratios through activated samples, requiring being corrected in thermal and epithermal energetic range by Westcott formalism. Furthermore, the comptage ratios measured for each photopeak to its decay fraction should be normalized from interrelation between both processes above, activation microscopic cross sections are obtained

  6. Distorted eikonal cross sections: A time-dependent view

    International Nuclear Information System (INIS)

    Turner, R.E.

    1982-01-01

    For Hamiltonians with two potentials, differential cross sections are written as time-correlation functions of reference and distorted transition operators. Distorted eikonal differential cross sections are defined in terms of straight-line and reference classical trajectories. Both elastic and inelastic results are obtained. Expressions for the inelastic cross sections are presented in terms of time-ordered cosine and sine memory functions through the use of the Zwanzig-Feshbach projection-operator method

  7. Discussion of electron cross sections for transport calculations

    International Nuclear Information System (INIS)

    Berger, M.J.

    1983-01-01

    This paper deals with selected aspects of the cross sections needed as input for transport calculations and for the modeling of radiation effects in biological materials. Attention is centered mainly on the cross sections for inelastic interactions between electrons and water molecules and the use of these cross sections for the calculation of energy degradation spectra and of ionization and excitation yields. 40 references, 3 figures, 1 table

  8. Tachyonic ionization cross sections of hydrogenic systems

    Energy Technology Data Exchange (ETDEWEB)

    Tomaschitz, Roman [Department of Physics, Hiroshima University, 1-3-1 Kagami-yama, Higashi-Hiroshima 739-8526 (Japan)

    2005-03-11

    Transition rates for induced and spontaneous tachyon radiation in hydrogenic systems as well as the transversal and longitudinal ionization cross sections are derived. We investigate the interaction of the superluminal radiation field with matter in atomic bound-bound and bound-free transitions. Estimates are given for Ly-{alpha} transitions effected by superluminal quanta in hydrogen-like ions. The tachyonic photoelectric effect is scrutinized, in the Born approximation and at the ionization threshold. The angular maxima occur at different scattering angles in the transversal and longitudinal cross sections, which can be used to sift out longitudinal tachyonic quanta in a photon flux. We calculate the tachyonic ionization and recombination cross sections for Rydberg states and study their asymptotic scaling with respect to the principal quantum number. At the ionization threshold of highly excited states of order n {approx} 10{sup 4}, the longitudinal cross section starts to compete with photoionization, in recombination even at lower levels.

  9. Symmetric charge transfer cross section of uranium

    International Nuclear Information System (INIS)

    Shibata, Takemasa; Ogura, Koichi

    1995-03-01

    Symmetric charge transfer cross section of uranium was calculated under consideration of reaction paths. In the charge transfer reaction a d 3/2 electron in the U atom transfers into the d-electron site of U + ( 4 I 9/2 ) ion. The J value of the U atom produced after the reaction is 6, 5, 4 or 3, at impact energy below several tens eV, only resonant charge transfer in which the product atom is ground state (J=6) takes place. Therefore, the cross section is very small (4-5 x 10 -15 cm 2 ) compared with that considered so far. In the energy range of 100-1000eV the cross section increases with the impact energy because near resonant charge transfer in which an s-electron in the U atom transfers into the d-electron site of U + ion. Charge transfer cross section between U + in the first excited state (289 cm -1 ) and U in the ground state was also obtained. (author)

  10. NNLO jet cross sections by subtraction

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, G.; Bolzoni, P. [DESY, Platanenallee 6, D-15738 Zeuthen (Germany); Trocsanyi, Z. [CERN PH-TH, on leave from University of Debrecen and Institute of Nuclear Research of HAS, H-4001 P.O.Box 51 (Hungary)

    2010-08-15

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of the NNLO subtraction scheme of Refs. [G. Somogyi, Z. Trocsanyi, and V. Del Duca, JHEP 06, 024 (2005), (arXiv:hep-ph/0502226); G. Somogyi and Z. Trocsanyi, (2006), (arXiv:hep-ph/0609041); G. Somogyi, Z. Trocsanyi, and V. Del Duca, JHEP 01, 070 (2007), (arXiv:hep-ph/0609042); G. Somogyi and Z. Trocsanyi, JHEP 01, 052 (2007), (arXiv:hep-ph/0609043)] over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state.

  11. NNLO jet cross sections by subtraction

    International Nuclear Information System (INIS)

    Somogyi, G.; Bolzoni, P.; Trocsanyi, Z.

    2010-01-01

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of the NNLO subtraction scheme of Refs. [G. Somogyi, Z. Trocsanyi, and V. Del Duca, JHEP 06, 024 (2005), (arXiv:hep-ph/0502226); G. Somogyi and Z. Trocsanyi, (2006), (arXiv:hep-ph/0609041); G. Somogyi, Z. Trocsanyi, and V. Del Duca, JHEP 01, 070 (2007), (arXiv:hep-ph/0609042); G. Somogyi and Z. Trocsanyi, JHEP 01, 052 (2007), (arXiv:hep-ph/0609043)] over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state.

  12. FENDL/E. Evaluated nuclear data library of neutron nuclear interaction cross-sections and photon production cross-sections and photon-atom interaction cross sections for fusion applications. Version 1.1 of November 1994

    International Nuclear Information System (INIS)

    Pashchenko, A.B.; Wienke, H.; Ganesan, S.; McLaughlin, P.K.

    1996-01-01

    This document presents the description of a physical tape containing the basic evaluated nuclear data library of neutron nuclear interaction cross-sections and photon production cross-sections and photon-atom interaction cross-sections for fusion applications. It is part of FENDL, the evaluated nuclear data library for fusion applications. The nuclear data are available cost-free for distribution to interested scientists upon request. The data can also be retrieved by the user via online access through international computer networks. (author). 11 refs, 1 tab

  13. Average cross sections for the 252Cf neutron spectrum

    International Nuclear Information System (INIS)

    Dezso, Z.; Csikai, J.

    1977-01-01

    A number of average cross sections have been measured for 252 Cf neutrons in (n, γ), (n,p), (n,2n), (n,α) reactions by the activation method and for fission by fission chamber. Cross sections have been determined for 19 elements and 45 reactions. The (n,γ) cross section values lie in the interval from 0.3 to 200 mb. The data as a function of target neutron number increases up to about N=60 with minimum near to dosed shells. The values lie between 0.3 mb and 113 mb. These cross sections decrease significantly with increasing the threshold energy. The values are below 20 mb. The data do not exceed 10 mb. Average (n,p) cross sections as a function of the threshold energy and average fission cross sections as a function of Zsup(4/3)/A are shown. The results obtained are summarized in tables

  14. Dynamics of the cross flow heat exchanger for heating purposes

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, K [Karlsruhe Univ. (TH) (Germany, F.R.). Inst. fuer Mess- und Regelungstechnik mit Maschinenlaboratorium

    1980-09-01

    A series of publications is available on the dynamic behaviour of heat exchangers (or heat transmitters, respectively), the subject of which is to deal with direct methods or with refined starting models for this general theme. The bridging between both these manners of advance remained as a problem. The author tried in his own investigation to solve the problem, and indeed by the selection of the correct starting model. He succeeded in this way, in that he removed conceptually a finned pipe from an arbitrary place of a heat exchanger and, furthermore, cut out from this particular pipe an arbitrary section. This section now does not stand alone for itself because the processes, which occur upstream of this section at the air-side and the water-side, are the input quantities of the section, which changes them due to its static and dynamic behaviour and emits them again as output quantities. The author, therefore, treats at first the dynamic behaviour of the section, which is represented in a signal flow diagram and which is used to derive approximate solutions from it. Furthermore, the author discusses the evident derivation of the total behaviour of heat exchangers.

  15. Cross section library DOSCROS77 (in the SAND-II format)

    International Nuclear Information System (INIS)

    Zijp, W.L.; Nolthenius, H.J.; Borg, N.J.C.M. van der.

    1977-08-01

    The dosimetry cross section library DOSCROS77 is documented with tables, plots and cross section values averaged over a few reference spectra. This library is based on the ENDF/B-IV dosimetry file, supplemented with some other evaluations. The total number of reaction cross section sets incorporated in this library is 49 (+3 cover cross sections sets). The cross section data are available in a format which is suitable for the program SAND-II

  16. Heat transfer enhancement in cross-flow heat exchanger using vortex generator

    International Nuclear Information System (INIS)

    Yoo, S. Y.; Kwon, H. K.; Kim, B. C.; Park, D. S.; Lee, S. S.

    2003-01-01

    Fouling is very serious problem in heat exchanger because it rapidly deteriorates the performance of heat exchanger. Cross-flow heat exchanger with vortex generators is developed, which enhance heat transfer and reduce fouling. In the present heat exchanger, shell and baffle are removed from the conventional shell-and-tube heat exchanger. The naphthalene sublimation technique is employed to measure the local heat transfer coefficients. The experiments are performed for single circular tube, staggered array tube bank and in-line array tube bank with and without vortex generators. Local and average Nusselt numbers of single tube and tube bank with vortex generator are investigated and compared to those of without vortex generator

  17. First measurement of the Rayleigh cross section

    NARCIS (Netherlands)

    Naus, H.; Ubachs, W.

    2000-01-01

    Rayleigh cross section for N2, Ar and SF6 was performed using the technique of cavity ring-down spectroscopy (CRDS). The experiment was based on the assumption that scattering cross section is equal to the extinction in the absence of absorption. The theory explains the molecular origin of

  18. JSD1000: multi-group cross section sets for shielding materials

    International Nuclear Information System (INIS)

    Yamano, Naoki

    1984-03-01

    A multi-group cross section library for shielding safety analysis has been produced by using ENDF/B-IV. The library consists of ultra-fine group cross sections, fine-group cross sections, secondary gamma-ray production cross sections and effective macroscopic cross sections for typical shielding materials. Temperature dependent data at 300, 560 and 900 K have been also provided. Angular distributions of the group to group transfer cross section are defined by a new method of ''Direct Angular Representation'' (DAR) instead of the method of finite Legendre expansion. The library designated JSD1000 are stored in a direct access data base named DATA-POOL and data manipulations are available by using the DATA-POOL access package. The 3824 neutron group data of the ultra-fine group cross sections and the 100 neutron, 20 photon group cross sections are applicable to shielding safety analyses of nuclear facilities. This report provides detailed specifications and the access method for the JSD1000 library. (author)

  19. Parameterized representation of macroscopic cross section for PWR reactor

    International Nuclear Information System (INIS)

    Fiel, João Cláudio Batista; Carvalho da Silva, Fernando; Senra Martinez, Aquilino; Leal, Luiz C.

    2015-01-01

    Highlights: • This work describes a parameterized representation of the homogenized macroscopic cross section for PWR reactor. • Parameterization enables a quick determination of problem-dependent cross-sections to be used in few group calculations. • This work allows generating group cross-section data to perform PWR core calculations without computer code calculations. - Abstract: The purpose of this work is to describe, by means of Chebyshev polynomials, a parameterized representation of the homogenized macroscopic cross section for PWR fuel element as a function of soluble boron concentration, moderator temperature, fuel temperature, moderator density and 235 92 U enrichment. The cross-section data analyzed are fission, scattering, total, transport, absorption and capture. The parameterization enables a quick and easy determination of problem-dependent cross-sections to be used in few group calculations. The methodology presented in this paper will allow generation of group cross-section data from stored polynomials to perform PWR core calculations without the need to generate them based on computer code calculations using standard steps. The results obtained by the proposed methodology when compared with results from the SCALE code calculations show very good agreement

  20. The total collision cross section in the glory region

    International Nuclear Information System (INIS)

    Biesen, J.J.H. van den.

    1982-01-01

    Chapter 1 presents a calculation of approximate total cross sections in the glory region from noble gas potentials. The relations between the main features of the total cross section and the properties of the potential to which these are sensitive are extensively investigated in chapter II. A beam apparatus has been developed, which allows for accurate measurements on the total cross section. All effects due to the finite angular and velocity resolution of the apparatus can be eliminated from the data to yield actual total cross sections as a function of the relative velocity. This facilitates a comparison to total cross sections predicted by potentials available in the literature. A brief description of the apparatus and of the data reduction is given in chapter III. The total cross section data obtained for various noble gas combinations are presented and analysed in chapter IV, where also a large number of potentials proposed in the literature is tested. In chapter V the quenching of the glories in the case of a non-spherical interaction is analysed. Subsequently, total cross section data for some atom-molecule systems are discussed. (Auth.)

  1. Hardon cross sections at ultra high energies

    International Nuclear Information System (INIS)

    Yodh, G.B.

    1987-01-01

    A review of results on total hadronic cross sections at ultra high energies obtained from a study of longitudinal development of cosmic ray air showers is given. The experimental observations show that proton-air inelastic cross section increases from 275 mb to over 500 mb as the collision energy in the center of mass increases from 20 GeV to 20 TeV. The proton-air inelastic cross section, obtained from cosmic ray data at √s = 30 TeV, is compared with calculations using various different models for the energy variation of the parameters of the elementary proton-proton interaction. Three conclusions are derived

  2. Total cross section results for deuterium electrodisintegration

    International Nuclear Information System (INIS)

    Skopik, D.M.; Murphy, J.J. II; Shin, Y.M.

    1976-01-01

    Theoretical total cross sections for deuterium electrodisintegration are presented as a function of incident electron energy. The cross section has been calculated using virtual photon theory with Partovi's photodisintegration calculation for E/subx/ > 10 MeV and effective range theory for E/subx/ 2 H(e, n) reaction in Tokamak reactors

  3. Measurements of the charge exchange and dissociation cross-sections of the H{sub 2}+ ion in a wide energy range; Mesures des sections efficaces d'echange de charge et de dissociation des ions H{sub 2}{sup +} dans une large gamme d'energie (25 - 250 keV)

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    The dissociation, ionisation, and charge exchange cross-sections of molecular hydrogen ions H{sub 2}{sup +} passing through various gases, have been measured as a function of the energy of the ions. The energy range studied was from 25 to 250 keV. The reaction products, analysed by a magnetic field according to their e/m ratio, are collected on scintillation detectors. Two methods have made it possible to separate the various reactions leading to the formation of particles having the same e/m ratio. The first separates the particles according to their energy, the other selects those arriving simultaneously on two different detectors. The results show a large variation in the charge exchange cross-section with the energy of the H{sub 2}{sup +} ions. The variations in the dissociation and ionisation cross-sections are less pronounced. For a given energy, the values of the cross-sections increase with the atomic weight of the target particles. These measurements have been extended to the case of H{sub 2}{sup +} ions passing through a target of charged particles. Preliminary results show an increase in the cross-sections as compared to the preceding case. Finally the scattering of the reaction products has been studied; this scattering is due to the fact that the molecules formed during a reaction are in an unstable state and the nuclei or atoms diverge from each other. (author) [French] Les sections efficaces de dissociation, d'ionisation et d'echange de charge d'ions hydrogene moleculaires H{sub 2}{sup +} traversant differents gaz, ont ete mesurees en fonction de l'energie des ions. La gamme d'energie exploree est comprise entre 25 et 250 keV. Les produits de reactions, analyses suivant leur rapport e/m par un champ magnetique, sont recus sur des detecteurs a scintillations. Deux methodes ont permis de separer les diverses reactions conduisant a la formation de particules ayant meme rapport e/m. L'une classe les particules secondaires en energie, l'autre selectionne

  4. Electron-impact ionization cross section of rubidium

    International Nuclear Information System (INIS)

    Kim, Y.; Migdalek, J.; Siegel, W.; Bieron, J.

    1998-01-01

    A theoretical model for electron-impact ionization cross section has been applied to Rb and the theoretical cross section (from the threshold to 1 keV in incident energy) is in good agreement with the recent experimental data obtained using Rb atoms trapped in a magneto-optical trap. The theoretical model, called the binary-encounter endash dipole (BED) model, combines a modified Mott cross section with the high-energy behavior of Born cross sections. To obtain the continuum dipole oscillator strength df/dE of the 5s electron required in the BED model, we used Dirac-Fock continuum wave functions with a core polarization potential that reproduced the known position of the Cooper minimum in the photoionization cross section. For inner-shell ionization, we used a simpler version of df/dE, which retained the hydrogenic shape. The contributions of the 4p→4d, 5s, and 5p autoionizing excitations were estimated using the plane-wave Born approximation. As a by-product, we also present the dipole oscillator strengths for the 5s→np 1/2 and 5s→np 3/2 transitions for high principal quantum numbers n near the ionization threshold obtained from the Dirac-Fock wave functions with the same core polarization potential as that used for the continuum wave functions. copyright 1998 The American Physical Society

  5. Measurements of L-shell x-ray production cross-sections of Au and Ag by low energy electron impact

    International Nuclear Information System (INIS)

    Wu, Y; An, Z; Liu, M T; Duan, Y M; Tang, C H; Luo, Z M

    2004-01-01

    Au L α and L β and Ag L-shell x-ray production cross-sections by electron impact have been measured in the incident energy region from near threshold to about 25 keV. Thin films with thick aluminium substrates were used as targets in the experiments. The effect of directional and energy spreading of the electron beam within the active films and x-ray enhancement due to backscattering electrons and bremsstrahlung photons from the substrates are corrected by means of Monte Carlo simulations. The corrected experimental data provided by this method are compared with calculated cross-sections from a PWBA theory with Coulomb, relativistic and exchange corrections and with other experimental data available in the literature

  6. Measurement cross sections for radioisotopes production

    International Nuclear Information System (INIS)

    Garrido, E.

    2011-01-01

    New radioactive isotopes for nuclear medicine can be produced using particle accelerators. This is one goal of Arronax, a high energy - 70 MeV - high intensity - 2*350 μA - cyclotron set up in Nantes. A priority list was established containing β - - 47 Sc, 67 Cu - β + - 44 Sc, 64 Cu, 82 Sr/ 82 Rb, 68 Ge/ 68 Ga - and α emitters - 211 At. Among these radioisotopes, the Scandium 47 and the Copper 67 have a strong interest in targeted therapy. The optimization of their productions required a good knowledge of their cross-sections but also of all the contaminants created during irradiation. We launched on Arronax a program to measure these production cross-sections using the Stacked-Foils' technique. It consists in irradiating several groups of foils - target, monitor and degrader foils - and in measuring the produced isotopes by γ-spectrometry. The monitor - nat Cu or nat Ni - is used to correct beam loss whereas degrader foils are used to lower beam energy. We chose to study the nat Ti(p,X) 47 Sc and 68 Zn(p,2p) 67 Cu reactions. Targets are respectively natural Titanium foil - bought from Goodfellow - and enriched Zinc 68 deposited on Silver. In the latter case, Zn targets were prepared in-house - electroplating of 68 Zn - and a chemical separation between Copper and Gallium isotopes has to be made before γ counting. Cross-section values for more than 40 different reactions cross-sections have been obtained from 18 MeV to 68 MeV. A comparison with the Talys code is systematically done. Several parameters of theoretical models have been studied and we found that is not possible to reproduce faithfully all the cross-sections with a given set of parameters. (author)

  7. Neutron cross section libraries for analysis of fusion neutronics experiments

    International Nuclear Information System (INIS)

    Kosako, Kazuaki; Oyama, Yukio; Maekawa, Hiroshi; Nakamura, Tomoo

    1988-03-01

    We have prepared two computer code systems producing neutron cross section libraries to analyse fusion neutronics experiments. First system produces the neutron cross section library in ANISN format, i.e., the multi-group constants in group independent format. This library can be obtained by using the multi-group constant processing code system MACS-N and the ANISN format cross section compiling code CROKAS. Second system is for the continuous energy cross section library for the MCNP code. This library can be obtained by the nuclear data processing system NJOY which generates pointwise energy cross sections and the cross section compiling code MACROS for the MCNP library. In this report, we describe the production procedures for both types of the cross section libraries, and show six libraries with different conditions in ANISN format and a library for the MCNP code. (author)

  8. Temperature-dependent absorption cross sections for hydrogen peroxide vapor

    Science.gov (United States)

    Nicovich, J. M.; Wine, P. H.

    1988-01-01

    Relative absorption cross sections for hydrogen peroxide vapor were measured over the temperature ranges 285-381 K for lambda = 230 nm-295 nm and 300-381 K for lambda = 193 nm-350 nm. The well established 298 K cross sections at 202.6 and 228.8 nm were used as an absolute calibration. A significant temperature dependence was observed at the important tropospheric photolysis wavelengths lambda over 300 nm. Measured cross sections were extrapolated to lower temperatures, using a simple model which attributes the observed temperature dependence to enhanced absorption by molecules possessing one quantum of O-O stretch vibrational excitation. Upper tropospheric photodissociation rates calculated using the extrapolated cross sections are about 25 percent lower than those calculated using currently recommended 298 K cross sections.

  9. Calculation of the intermediate energy activation cross section

    Energy Technology Data Exchange (ETDEWEB)

    Furihata, Shiori; Yoshizawa, Nobuaki [Mitsubishi Research Inst., Inc., Tokyo (Japan)

    1997-03-01

    We discussed the activation cross section in order to predict accurately the activation of soil around an accelerator with high energy and strong intensity beam. For the assessment of the accuracy of activation cross sections estimated by a numerical model, we compared the calculated cross section with various experimental data, for Si(p,x){sup 22}Na, Al(p,x){sup 22}Na, Fe(p,x){sup 22}Na, Si(p,x){sup 7}Be, O(p,x){sup 3}H, Al(p,x){sup 3}H and Si(p,x){sup 3}H reactions. We used three computational codes, i.e., quantum molecular dynamics (QMD) plus statistical decay model (SDM), HETC-3STEP and the semiempirical method developed by Silberberg et.al. It is observed that the codes are accurate above 1GeV, except for {sup 7}Be production. We also discussed the difference between the activation cross sections of proton- and neutron-induced reaction. For the incident energy at 40MeV, it is found that {sup 3}H production cross sections of neutron-induced reaction are ten times as large as those of proton-induced reaction. It is also observed that the choice of the activation cross sections seriously affects to the estimate of saturated radioactivity, if the maximum energy of neutron flux is below 100MeV. (author)

  10. Validation of evaluated neutron standard cross sections

    International Nuclear Information System (INIS)

    Badikov, S.; Golashvili, T.

    2008-01-01

    Some steps of the validation and verification of the new version of the evaluated neutron standard cross sections were carried out. In particular: -) the evaluated covariance data was checked for physical consistency, -) energy-dependent evaluated cross-sections were tested in most important neutron benchmark field - 252 Cf spontaneous fission neutron field, -) a procedure of folding differential standard neutron data in group representation for preparation of specialized libraries of the neutron standards was verified. The results of the validation and verification of the neutron standards can be summarized as follows: a) the covariance data of the evaluated neutron standards is physically consistent since all the covariance matrices of the evaluated cross sections are positive definite, b) the 252 Cf spectrum averaged standard cross-sections are in agreement with the evaluated integral data (except for 197 Au(n,γ) reaction), c) a procedure of folding differential standard neutron data in group representation was tested, as a result a specialized library of neutron standards in the ABBN 28-group structure was prepared for use in reactor applications. (authors)

  11. View-CXS neutron and photon cross-sections viewer

    International Nuclear Information System (INIS)

    Subbaiah, K.V.; Sunil Sunny, C.

    2004-01-01

    A graphical user-friendly interface is developed in Visual Basic (VB)-6 to view the variation of neutron and photon interaction cross-sections of different isotopes as a function of energy. VB subroutines developed read the binary data files of cross-sections created in MCNP-ACE (Briesmeister, J.F., 1993. MCNP - a general purpose Monte Carlo N-Particle Transport code. Version 4A. LANL, USA), ANISN-DLC (Engle W.W. Jr., 1967, A User's Manual for ANISN, K-1693; ORNL, 1974. 100 group neutron cross section data based on ENDF/B-III. Oak Ridge National Laboratory, USA) and KENO-AMPX (Petrie, L.M., Landers, N.F., 1984 KENO-Va- An Improved Monte Carlo Criticality Program with Super Grouping. RSICC-CCC-548, USA) formats using LAHEY-77 Fortran Compiler. The information on isotopes present in each library will be displayed with the help of database files prepared using Micro-Soft ACESS. The cross-section data can be viewed in different presentation styles namely, line graphs, bar graphs, histograms etc., with different color and symbol options. The cross-section plots generated can be saved as Bit-Map file to embed in any other text files. This software enables inter comparison of cross-sections from different type of libraries for isotopes as well as mixtures. Provision is made to view the cross-sections for nuclear reactions such as (n,γ), (n,f), (n,α), etc. The software can be obtained from Radiation Safety Information and Computational Centre (RSICC), ORNL, USA with the code package identification number PSR-514. The software package needs a hard disk space of about 80 MB when installed and works in WINDOWS-95/98/2000 operating systems

  12. Optical Model and Cross Section Uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Herman,M.W.; Pigni, M.T.; Dietrich, F.S.; Oblozinsky, P.

    2009-10-05

    Distinct minima and maxima in the neutron total cross section uncertainties were observed in model calculations using spherical optical potential. We found this oscillating structure to be a general feature of quantum mechanical wave scattering. Specifically, we analyzed neutron interaction with 56Fe from 1 keV up to 65 MeV, and investigated physical origin of the minima.We discuss their potential importance for practical applications as well as the implications for the uncertainties in total and absorption cross sections.

  13. Pion-nucleus cross sections

    International Nuclear Information System (INIS)

    Barashenkov, V.S.

    1990-01-01

    The tables of inelastic and total cross sections of π ± mesons interactions with nuclei 4 He- 238 U are presented. The tables are obtained by theoretical analysis of known experimental data for energies higher some tens of MeV. 1 ref.; 1 tab

  14. Proton-air and proton-proton cross sections

    Directory of Open Access Journals (Sweden)

    Ulrich Ralf

    2013-06-01

    Full Text Available Different attempts to measure hadronic cross sections with cosmic ray data are reviewed. The major results are compared to each other and the differences in the corresponding analyses are discussed. Besides some important differences, it is crucial to see that all analyses are based on the same fundamental relation of longitudinal air shower development to the observed fluctuation of experimental observables. Furthermore, the relation of the measured proton-air to the more fundamental proton-proton cross section is discussed. The current global picture combines hadronic proton-proton cross section data from accelerator and cosmic ray measurements and indicates a good consistency with predictions of models up to the highest energies.

  15. Fission-neutron displacement cross sections in metals

    International Nuclear Information System (INIS)

    Takamura, Saburo; Aruga, Takeo; Nakata, Kiyotomo

    1985-01-01

    The sensitivity damage rates for 22 metals were measured after fission-spectrum neutron irradiation at low temperature and the experimental damage rates were compared with the theoretical calculation. The relation between the theoretical displacement cross section and the atomic weight of metals can be written by two curves; one is for fcc and hcp metals, and another is for bcc metals. On the other hand, the experimental displacement cross section versus atomic weight is shown approximately by a curve for both fcc and bcc metals, and the cross section for hcp metals deviates from the curve. The defect production efficiency is 0.3-0.4 for fcc metals and 0.6-0.8 for bcc metals. (orig.)

  16. Compact fitting formulas for electron-impact cross sections

    International Nuclear Information System (INIS)

    Kim, Y.K.

    1992-01-01

    Compact fitting formulas, which contain four fitting constants, are presented for electron-impact excitation and ionization cross sections of atoms and ions. These formulas can fit experimental and theoretical cross sections remarkably well, when resonant structures are smoothed out, from threshold to high incident electron energies (<10 keV), beyond which relativistic formulas are more appropriate. Examples of fitted cross sections for some atoms and ions are presented. The basic form of the formula is valid for both atoms and molecules

  17. Single-level resonance parameters fit nuclear cross-sections

    Science.gov (United States)

    Drawbaugh, D. W.; Gibson, G.; Miller, M.; Page, S. L.

    1970-01-01

    Least squares analyses of experimental differential cross-section data for the U-235 nucleus have yielded single level Breit-Wigner resonance parameters that fit, simultaneously, three nuclear cross sections of capture, fission, and total.

  18. Approximate N3LO Higgs-boson production cross section using physical-kernel constraints

    International Nuclear Information System (INIS)

    Florian, D. de; Moch, S.; Hamburg Univ.; Vogt, A.

    2014-08-01

    The single-logarithmic enhancement of the physical kernel for Higgs production by gluon-gluon fusion in the heavy top-quark limit is employed to derive the leading so far unknown contributions, ln 5,4,3 (1-z), to the N 3 LO coefficient function in the threshold expansion. Also using knowledge from Higgs-exchange DIS to estimate the remaining terms not vanishing for z=m 2 H /s→1, these results are combined with the recently completed soft+virtual contributions to provide an uncertainty band for the complete N 3 LO correction. For the 2008 MSTW parton distributions these N 3 LO contributions increase the cross section at 14 TeV by (10±2)% and (3±2.5)% for the standard choices μ R =m H and μ R =m H /2 of the renormalization scale. The remaining uncertainty arising from the hard-scattering cross sections can be quantified as no more than 5%, which is smaller than that due to the strong coupling and the parton distributions.

  19. Data Leakage Prevention for Secure Cross-Domain Information Exchange

    OpenAIRE

    Nordbotten, Nils Agne; Engelstad, Paal E.; Kongsgård, Kyrre Wahl; Haakseth, Raymond; Mancini, Federico

    2017-01-01

    Cross-domain information exchange is an increasingly important capability for conducting efficient and secure operations, both within coalitions and within single nations. A data guard is a common cross-domain sharing solution that inspects the security labels of exported data objects and validates that they are such that they can be released according to policy. While we see that guard solutions can be implemented with high assurance, we find that obtaining an equivalent level of assurance i...

  20. Total cross section of highly excited strings

    International Nuclear Information System (INIS)

    Lizzi, F.; Senda, I.

    1990-01-01

    The unpolarized total cross section for the joining of two highly excited strings is calculated. The calculation is performed by taking the average overall states in the given excitation levels of the initial strings. We find that the total cross section grows with the energy and momentum of the initial states. (author). 8 refs, 1 fig

  1. MXS cross-section preprocessor user's manual

    International Nuclear Information System (INIS)

    Parker, F.; Ishikawa, M.; Luck, L.

    1987-03-01

    The MXS preprocessor has been designed to reduce the execution time of programs using isotopic cross-section data and to both reduce the execution time and improve the accuracy of shielding-factor interpolation in the SIMMER-II accident analysis program. MXS is a dual-purpose preprocessing code to: (1) mix isotopes into materials and (2) fit analytic functions to the shelf-shielding data. The program uses the isotope microscopic neutron cross-section data from the CCCC standard interface file ISOTXS and the isotope Bondarenko self-shielding data from the CCCC standard interface file BRKOXS to generate cross-section and self-shielding data for materials. The materials may be a mixture of several isotopes. The self-shielding data for the materials may be the actual shielding factors or a set of coefficients for functions representing the background dependence of the shielding factors. A set of additional data is given to describe the functions necessary to interpolate the shielding factors over temperature

  2. Neutron capture cross sections of Kr

    Directory of Open Access Journals (Sweden)

    Fiebiger Stefan

    2017-01-01

    Full Text Available Neutron capture and β− -decay are competing branches of the s-process nucleosynthesis path at 85Kr [1], which makes it an important branching point. The knowledge of its neutron capture cross section is therefore essential to constrain stellar models of nucleosynthesis. Despite its importance for different fields, no direct measurement of the cross section of 85Kr in the keV-regime has been performed. The currently reported uncertainties are still in the order of 50% [2, 3]. Neutron capture cross section measurements on a 4% enriched 85Kr gas enclosed in a stainless steel cylinder were performed at Los Alamos National Laboratory (LANL using the Detector for Advanced Neutron Capture Experiments (DANCE. 85Kr is radioactive isotope with a half life of 10.8 years. As this was a low-enrichment sample, the main contaminants, the stable krypton isotopes 83Kr and 86Kr, were also investigated. The material was highly enriched and contained in pressurized stainless steel spheres.

  3. NNLO jet cross sections by subtraction

    Science.gov (United States)

    Somogyi, G.; Bolzoni, P.; Trócsányi, Z.

    2010-08-01

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of the NNLO subtraction scheme of Refs. [G. Somogyi, Z. Trócsányi, and V. Del Duca, JHEP 06, 024 (2005), arXiv:hep-ph/0502226; G. Somogyi and Z. Trócsányi, (2006), arXiv:hep-ph/0609041; G. Somogyi, Z. Trócsányi, and V. Del Duca, JHEP 01, 070 (2007), arXiv:hep-ph/0609042; G. Somogyi and Z. Trócsányi, JHEP 01, 052 (2007), arXiv:hep-ph/0609043] over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state.

  4. Two models for the dynamics of a cross flow heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Hopkinson, A [Control and Instrumentation Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1962-12-15

    Two models of a cross flow heat exchanger, a concentric tube counter flow model and a cross flow model, are studied theoretically. Differential equations describing the behaviour of the models are derived and from them equations for the steady state temperatures and the temperature transfer functions are obtained. (author)

  5. Measurement of the cross section for diffractive deep-inelastic scattering with a leading proton at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Aaron, F.D.; Alexa, C.; Rotaru, M.; Stoicea, G. [National Inst. for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Andreev, V.; Belousov, A.; Eliseev, A.; Fomenko, A.; Gogitidze, N.; Lebedev, A.; Loktionova, N.; Malinovski, E.; Rusakov, S.; Shtarkov, L.N.; Soloviev, Y.; Vazdik, Y. [Lebedev Physical Inst., Moscow (Russian Federation); Backovic, S.; Dubak, A.; Lastovicka-Medin, G.; Picuric, I.; Raicevic, N. [Univ. of Montenegro, Faculty of Science, Podgorica (ME); Baghdasaryan, A.; Zohrabyan, H. [Yerevan Physics Inst., Yerevan (Armenia); Barrelet, E. [Univ. Pierre et Marie Curie Paris 6, Univ. Denis Diderot Paris 7, CNRS/IN2P3, LPNHE, Paris (France); Bartel, W.; Brandt, G.; Brinkmann, M.; Britzger, D.; Campbell, A.J.; Cholewa, A.; Deak, M.; Eckerlin, G.; Elsen, E.; Felst, R.; Fischer, D.J.; Fleischer, M.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Gouzevitch, M.; Grebenyuk, A.; Grell, B.R.; Habib, S.; Haidt, D.; Helebrant, C.; Katzy, J.; Kleinwort, C.; Knutsson, A.; Kraemer, M.; Kutak, K.; Levonian, S.; Lipka, K.; List, J.; Meyer, A.B.; Meyer, J.; Niebuhr, C.; Nikiforov, A.; Nowak, K.; Olsson, J.E.; Pahl, P.; Panagoulias, I.; Papadopoulou, T.; Petrukhin, A.; Piec, S.; Pitzl, D.; Placakyte, R.; Schmitt, S.; Sefkow, F.; Staykova, Z.; Steder, M.; Toll, T.; Vargas Trevino, A.; Driesch, M. von den; Wuensch, E. [DESY, Hamburg (Germany); Begzsuren, K.; Ravdandorj, T.; Tseepeldorj, B. [Inst. of Physics and Technology of the Mongolian Academy of Sciences, Ulaanbaatar (Mongolia); Bizot, J.C.; Brisson, V.; Delcourt, B.; Jacquet, M.; Pascaud, C.; Tran, T.H.; Zhang, Z.; Zomer, F. [Universite Paris-Sud, CNRS/IN2P3, LAL, Orsay (France); Boudry, V.; Moreau, F.; Specka, A. [Ecole Polytechnique, CNRS/IN2P3, LLR, Palaiseau (France); Bozovic-Jelisavcic, I.; Mudrinic, M.; Pandurovic, M.; Smiljanic, I. [Vinca Inst. of Nuclear Sciences, Belgrade (RS); Bracinik, J.; Kenyon, I.R.; Newman, P.R.; Thompson, P.D. [Univ. of Birmingham, Birmingham (United Kingdom)

    2011-03-15

    The cross section for the diffractive deep-inelastic scattering process ep{yields}eXp is measured, with the leading final state proton detected in the H1 Forward Proton Spectrometer. The data sample covers the range x{sub P}<0.1 in fractional proton longitudinal momentum loss, 0.1< vertical stroke t vertical stroke <0.7 GeV{sup 2} in squared four-momentum transfer at the proton vertex and 4cross section is measured four-fold differentially in t,x{sub P},Q {sup 2} and {beta}=x/x{sub P}, where x is the Bjorken scaling variable. The t and x{sub P} dependences are interpreted in terms of an effective pomeron trajectory and a sub-leading exchange. The data are compared with perturbative QCD predictions at next-to-leading order based on diffractive parton distribution functions previously extracted from complementary measurements of inclusive diffractive deep-inelastic scattering. The ratio of the diffractive to the inclusive ep cross section is studied as a function of Q{sup 2},{beta} and x{sub P}. (orig.)

  6. Mid-IR Absorption Cross-Section Measurements of Hydrocarbons

    KAUST Repository

    Alrefae, Majed Abdullah

    2013-01-01

    -known at combustion-relevant conditions. Absorption cross-section is an important spectroscopic quantity and has direct relation to the species concentration. In this work, the absorption cross-sections of basic hydrocarbons are measured using Fourier Transform

  7. LHCb cross-section measurements with heavy flavour jets

    CERN Multimedia

    Michielin, Emanuele

    2017-01-01

    Cross-section measurements of jets originating from the hadronization of beauty ($b$) and charm ($c$) quarks at LHCb give the unique opportunity to probe Parton Distribution Functions (PDFs) at low and large momentum fraction and to test the Standard Model in the forward region. In this poster the production of $t\\bar{t}$ pairs in the forward region, the measurement of the $W+b\\bar{b}$ and $W+c\\bar{c}$ cross-section and the measurement of the $Z\\rightarrow b\\bar{b}$ cross-section are presented.

  8. Gain measurements of the Ca-Xe charge exchange system. [for UV lasers

    Science.gov (United States)

    Michels, C. J.; Chubb, D. L.

    1978-01-01

    Charge-exchange-pumped Ca(+) was studied for possible positive laser gain at 370.6 and 315.9 nm using an Xe MPD arc as the Xe(+) source. The present paper describes the MPD arc, the calcium injection system, the diagnostics for gain, and spontaneous emission measurements and results. No positive gain measurements were observed. A small Xe-Ca charge exchange cross section compared to He-metal laser systems charge exchange cross sections is the most probable reason why the result was negative.

  9. Neutron cross section measurements for the Fast Breeder Program

    International Nuclear Information System (INIS)

    Block, R.C.

    1979-06-01

    This research was concerned with the measurement of neutron cross sections of importance to the Fast Breeder Reactor. The capture and total cross sections of fission products ( 101 102 104 Ru, 143 145 Nd, 149 Sm, 95 97 Mo, Cs, Pr, Pd, 107 Pd, 99 Tc) and tag gases (Kr, 78 80 Kr) were measured up to 100 keV. Filtered neutron beams were used to measure the capture cross section of 238 U (with an Fe filter) and the total cross section of Na (with a Na filter). A radioactive neutron capture detector was developed. A list of publications is included

  10. Developing Scientific Reasoning Through Drawing Cross-Sections

    Science.gov (United States)

    Hannula, K. A.

    2012-12-01

    Cross-sections and 3D models of subsurface geology are typically based on incomplete information (whether surface geologic mapping, well logs, or geophysical data). Creating and evaluating those models requires spatial and quantitative thinking skills (including penetrative thinking, understanding of horizontality, mental rotation and animation, and scaling). However, evaluating the reasonableness of a cross-section or 3D structural model also requires consideration of multiple possible geometries and geologic histories. Teaching students to create good models requires application of the scientific methods of the geosciences (such as evaluation of multiple hypotheses and combining evidence from multiple techniques). Teaching these critical thinking skills, especially combined with teaching spatial thinking skills, is challenging. My Structural Geology and Advanced Structural Geology courses have taken two different approaches to developing both the abilities to visualize and to test multiple models. In the final project in Structural Geology (a 3rd year course with a pre-requisite sophomore mapping course), students create a viable cross-section across part of the Wyoming thrust belt by hand, based on a published 1:62,500 geologic map. The cross-section must meet a number of geometric criteria (such as the template constraint), but is not required to balance. Each student tries many potential geometries while trying to find a viable solution. In most cases, the students don't visualize the implications of the geometries that they try, but have to draw them and then erase their work if it does not meet the criteria for validity. The Advanced Structural Geology course used Midland Valley's Move suite to test the cross-sections that they made in Structural Geology, mostly using the flexural slip unfolding algorithm and testing whether the resulting line lengths balanced. In both exercises, students seemed more confident in the quality of their cross-sections when the

  11. The measurement of antiproton-proton total cross sections and small-angle elastic scattering at low momentum

    International Nuclear Information System (INIS)

    Linssen, L.H.A.J.

    1986-01-01

    In this thesis two low-momentum antiproton-proton (anti pp) experiments are described. The first one is a set of 24 high statistics anti pp total cross section measurements as a function of the incoming antiproton momentum between p=388 MeV/c and p=599 MeV/c. These measurements simultaneously yield the charge exchange cross section (anti pp → anti nn). The second one comprises two high statistics anti pp small-angle elastic scattering measurements at p=233 MeV/c and p=272 MeV/c. The measurements were carried out using the high quality antiproton beam extracted from the Low Energy Antiproton Ring (LEAR) at CERN. The physics motivation for these experiments is a search for anti pp resonances or bound states on one hand, and a detailed study of the anti pp interaction on the other hand. (orig.)

  12. Applications of the BEam Cross section Analysis Software (BECAS)

    DEFF Research Database (Denmark)

    Blasques, José Pedro Albergaria Amaral; Bitsche, Robert; Fedorov, Vladimir

    2013-01-01

    A newly developed framework is presented for structural design and analysis of long slender beam-like structures, e.g., wind turbine blades. The framework is based on the BEam Cross section Analysis Software – BECAS – a finite element based cross section analysis tool. BECAS is used for the gener......A newly developed framework is presented for structural design and analysis of long slender beam-like structures, e.g., wind turbine blades. The framework is based on the BEam Cross section Analysis Software – BECAS – a finite element based cross section analysis tool. BECAS is used...... for the generation of beam finite element models which correctly account for effects stemming from material anisotropy and inhomogeneity in cross sections of arbitrary geometry. These type of modelling approach allows for an accurate yet computationally inexpensive representation of a general class of three...

  13. Absolute photoionization cross-section of the methyl radical.

    Science.gov (United States)

    Taatjes, Craig A; Osborn, David L; Selby, Talitha M; Meloni, Giovanni; Fan, Haiyan; Pratt, Stephen T

    2008-10-02

    The absolute photoionization cross-section of the methyl radical has been measured using two completely independent methods. The CH3 photoionization cross-section was determined relative to that of acetone and methyl vinyl ketone at photon energies of 10.2 and 11.0 eV by using a pulsed laser-photolysis/time-resolved synchrotron photoionization mass spectrometry method. The time-resolved depletion of the acetone or methyl vinyl ketone precursor and the production of methyl radicals following 193 nm photolysis are monitored simultaneously by using time-resolved synchrotron photoionization mass spectrometry. Comparison of the initial methyl signal with the decrease in precursor signal, in combination with previously measured absolute photoionization cross-sections of the precursors, yields the absolute photoionization cross-section of the methyl radical; sigma(CH3)(10.2 eV) = (5.7 +/- 0.9) x 10(-18) cm(2) and sigma(CH3)(11.0 eV) = (6.0 +/- 2.0) x 10(-18) cm(2). The photoionization cross-section for vinyl radical determined by photolysis of methyl vinyl ketone is in good agreement with previous measurements. The methyl radical photoionization cross-section was also independently measured relative to that of the iodine atom by comparison of ionization signals from CH3 and I fragments following 266 nm photolysis of methyl iodide in a molecular-beam ion-imaging apparatus. These measurements gave a cross-section of (5.4 +/- 2.0) x 10(-18) cm(2) at 10.460 eV, (5.5 +/- 2.0) x 10(-18) cm(2) at 10.466 eV, and (4.9 +/- 2.0) x 10(-18) cm(2) at 10.471 eV. The measurements allow relative photoionization efficiency spectra of methyl radical to be placed on an absolute scale and will facilitate quantitative measurements of methyl concentrations by photoionization mass spectrometry.

  14. Cross-section crushing behaviour of hat-sections (Part II: Analytical modelling)

    NARCIS (Netherlands)

    Hofmeyer, H.

    2005-01-01

    Hat-sections are often used to experimentally investigate building sheeting subject to a concentrated load and bending. In car doors, hat-sections are used for side-impact protection. Their crushing behaviour can partly be explained by only observing their cross-sectional behaviour [1]. This

  15. Asymptotic behaviour of pion-pion total cross-sections

    Energy Technology Data Exchange (ETDEWEB)

    Greynat, David [Dipartimento di Scienze Fisiche, Universita di Napoli “Federico II”,Via Cintia, 80126 Napoli (Italy); Rafael, Eduardo de [Aix-Marseille Université, CNRS,CPT, UMR 7332, 13288 Marseille (France); Université de Toulon, CNRS,CPT, UMR 7332, 83957 La Garde (France); Vulvert, Grégory [Departament de Física Teórica, IFIC,CSIC - Universitat de València, Apt. Correus 22085, E-46071 València (Spain)

    2014-03-24

    We derive a sum rule which shows that the Froissart-Martin bound for the asymptotic behaviour of the ππ total cross sections at high energies, if modulated by the Lukaszuk-Martin coefficient of the leading log{sup 2} s behaviour, cannot be an optimal bound in QCD. We next compute the total cross sections for π{sup +}π{sup −}, π{sup ±}π{sup 0} and π{sup 0}π{sup 0} scattering within the framework of the constituent chiral quark model (CχQM) in the limit of a large number of colours N{sub c} and discuss their asymptotic behaviours. The same ππ cross sections are also discussed within the general framework of Large-N{sub c} QCD and we show that it is possible to make an Ansatz for the isospin I=1 and I=0 spectrum which satisfy the Froissart-Martin bound with coefficients which, contrary to the Lukaszuk-Martin coefficient, are not singular in the chiral limit and have the correct Large-N{sub c} counting. We finally propose a simple phenomenological model which matches the low energy behaviours of the σ{sub π{sup ±}π{sup 0total}}(s) cross section predicted by the CχQM with the high energy behaviour predicted by the Large-N{sub c} Ansatz. The magnitude of these cross sections at very high energies is of the order of those observed for the pp and pp-bar scattering total cross sections.

  16. Asymptotic behaviour of pion-pion total cross-sections

    International Nuclear Information System (INIS)

    Greynat, David; Rafael, Eduardo de; Vulvert, Grégory

    2014-01-01

    We derive a sum rule which shows that the Froissart-Martin bound for the asymptotic behaviour of the ππ total cross sections at high energies, if modulated by the Lukaszuk-Martin coefficient of the leading log 2  s behaviour, cannot be an optimal bound in QCD. We next compute the total cross sections for π + π − , π ± π 0 and π 0 π 0 scattering within the framework of the constituent chiral quark model (CχQM) in the limit of a large number of colours N c and discuss their asymptotic behaviours. The same ππ cross sections are also discussed within the general framework of Large-N c QCD and we show that it is possible to make an Ansatz for the isospin I=1 and I=0 spectrum which satisfy the Froissart-Martin bound with coefficients which, contrary to the Lukaszuk-Martin coefficient, are not singular in the chiral limit and have the correct Large-N c counting. We finally propose a simple phenomenological model which matches the low energy behaviours of the σ π ± π 0 total (s) cross section predicted by the CχQM with the high energy behaviour predicted by the Large-N c Ansatz. The magnitude of these cross sections at very high energies is of the order of those observed for the pp and pp-bar scattering total cross sections

  17. Improved extraction of two-photon exchange amplitudes from elastic electron-proton scattering cross section data up to Q2=5.20 (GeV/c ) 2

    Science.gov (United States)

    Qattan, I. A.; Homouz, D.; Riahi, M. K.

    2018-04-01

    In this work, we improve on and extend to low- and high-Q2 values the extractions of the two-photon-exchange (TPE) amplitudes and the ratio Pl/PlBorn(ɛ ,Q2) using world data on electron-proton elastic scattering cross section σR(ɛ ,Q2) with an emphasis on data covering the high-momentum region, up to Q2=5.20 (GeV/c ) 2 , to better constrain the TPE amplitudes in this region. We provide a new parametrization of the TPE amplitudes, along with an estimate of the fit uncertainties. We compare the results to several previous phenomenological extractions and hadronic TPE predictions. We use the new parametrization of the TPE amplitudes to extract the ratio Pl/PlBorn(ɛ ,Q2) , and then compare the results to previous extractions, several theoretical calculations, and direct measurements at Q2=2.50 (GeV/c ) 2 .

  18. Collision cross sections of N2 by H+ impact at keV energies within time-dependent density-functional theory

    Science.gov (United States)

    Yu, W.; Gao, C.-Z.; Zhang, Y.; Zhang, F. S.; Hutton, R.; Zou, Y.; Wei, B.

    2018-03-01

    We calculate electron capture and ionization cross sections of N2 impacted by the H+ projectile at keV energies. To this end, we employ the time-dependent density-functional theory coupled nonadiabatically to molecular dynamics. To avoid the explicit treatment of the complex density matrix in the calculation of cross sections, we propose an approximate method based on the assumption of constant ionization rate over the period of the projectile passing the absorbing boundary. Our results agree reasonably well with experimental data and semi-empirical results within the measurement uncertainties in the considered energy range. The discrepancies are mainly attributed to the inadequate description of exchange-correlation functional and the crude approximation for constant ionization rate. Although the present approach does not predict the experiments quantitatively for collision energies below 10 keV, it is still helpful to calculate total cross sections of ion-molecule collisions within a certain energy range.

  19. Stopping cross section of vanadium for H+ and He+ ions in a large energy interval deduced from backscattering spectra

    Science.gov (United States)

    Moro, M. V.; Bruckner, B.; Grande, P. L.; Tabacniks, M. H.; Bauer, P.; Primetzhofer, D.

    2018-06-01

    We have experimentally determined electronic stopping cross sections of vanadium for 50-2750 keV protons and for 250-6000 keV He ions by relative measurements in backscattering geometry. To check the consistency of the employed procedure we investigate how to define adequate reference stopping cross section data and chose different reference materials. To proof consistency of different reference data sets, an intercomparison is performed to test the reliability of the evaluation procedure for a wide range of energies. This process yielded consistent results. The resulting stopping cross section data for V are compared to values from the IAEA database, to the most commonly employed semi-empirical program SRIM, and to calculations according to CasP. For helium, our results show a significant deviation of up to 10% with respect to literature and to SRIM, but are in very good agreement with the CasP predictions, in particular when charge-exchange processes are included in the model.

  20. Neutron total scattering cross sections of elemental antimony

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.B.; Guenther, P.T.; Whalen, J.F.

    1982-11-01

    Neutron total cross sections are measured from 0.8 to 4.5 MeV with broad resolutions. Differential-neutron-elastic-scattering cross sections are measured from 1.5 to 4.0 MeV at intervals of 50 to 200 keV and at scattering angles distributed between 20 and 160 degrees. Lumped-level neutron-inelastic-scattering cross sections are measured over the same angular and energy range. The exPerimental results are discussed in terms of an optical-statistical model and are compared with respective values given in ENDF/B-V.

  1. Neutron total scattering cross sections of elemental antimony

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.; Whalen, J.F.

    1982-11-01

    Neutron total cross sections are measured from 0.8 to 4.5 MeV with broad resolutions. Differential-neutron-elastic-scattering cross sections are measured from 1.5 to 4.0 MeV at intervals of 50 to 200 keV and at scattering angles distributed between 20 and 160 degrees. Lumped-level neutron-inelastic-scattering cross sections are measured over the same angular and energy range. The exPerimental results are discussed in terms of an optical-statistical model and are compared with respective values given in ENDF/B-V

  2. Total cross sections for heavy flavour production at HERA

    CERN Document Server

    Frixione, Stefano; Nason, P; Ridolfi, G; Frixione, S; Mangano, M L; Nason, P; Ridolfi, G

    1995-01-01

    We compute total cross sections for charm and bottom photoproduction at HERA energies, and discuss the relevant theoretical uncertainties. In particular we discuss the problems arising from the small-x region, the uncertainties in the gluon parton density, and the uncertainties in the hadronic component of the cross section. Total electroproduction cross sections, calculated in the Weizs\\"acker-Williams approximation, are also given.

  3. Heavy flavour hadro-production cross-sections

    CERN Document Server

    Wöhri, H K

    2003-01-01

    Hadro-production data on charm and beauty absolute cross-sections, collected by experiments at CERN, DESY and Fermilab, are reviewed. The measurements, corrected for the 'time evolution' of the branching ratios, are compared to calculations done with Pythia, as a function of the collision energy, using the latest parametrizations of the parton densities. We then estimate some charm and beauty production cross-sections relevant for future measurements, including nuclear effectes in the PDFs. We finish by briefly addressing the relevance, in heavy-ion collisions, of beauty production as feed-down for J/psi production.

  4. Evaluated activation cross-sections and intercomparison of the ...

    Indian Academy of Sciences (India)

    mental data cross-section with the theoretical codes, to study the quality of the theoretical ... the cross-section, angular distribution, double differential data, gamma ..... TALYS. TENDL. Figure 6. Excitation function of the 87Sr(p, 2n)86Y reaction.

  5. Observational constraints on dark matter-dark energy scattering cross section

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Suresh [BITS Pilani, Department of Mathematics, Rajasthan (India); Nunes, Rafael C. [Universidade Federal de Juiz de Fora, Departamento de Fisica, Juiz de Fora, MG (Brazil)

    2017-11-15

    In this letter, we report precise and robust observational constraints on the dark matter-dark energy scattering cross section, using the latest data from cosmic microwave background (CMB) Planck temperature and polarization, baryon acoustic oscillations (BAO) measurements and weak gravitational lensing data from Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). The scattering scenario consists of a pure momentum exchange between the dark components, and we find σ{sub d} < 10{sup -29} cm{sup 2} (m{sub dm}c{sup 2}/GeV) at 95% CL from the joint analysis (CMB + BAO + CFHTLenS), where m{sub dm} is a typical dark matter particle mass. We notice that the scattering among the dark components may influence the growth of large scale structure in the Universe, leaving the background cosmology unaltered. (orig.)

  6. Implementation of nonseparable exact exchange effects in the first-order nondegenerate adiabatic theory

    International Nuclear Information System (INIS)

    Abdolsalami, M.; Abdolsalami, F.; Gonzalez, H.R.

    1994-01-01

    We have implemented nonlocal exchange effects rigorously in the first-order nondegenerate adiabatic (FONDA) theory. This implementation requires solving integrodifferential equations that involve double integrals. Separable and model exchange approximations that simplify the inclusion of exchange in the scattering calculations have been previously implemented in the FONDA theory. The discrepancy between the exact exchange FONDA cross sections and the separable and model exchange results suggests that one needs to include exchange rigorously to obtain accurate results over a wide range of energies. Specifically, a difference of up to 30% is observed between the exact and separable exchange FONDA cross sections at near-threshold energies. At higher energies the FONDA results from the rigorous and model exchange implementations disagree by as much as 10%

  7. Positron induced scattering cross sections for hydrocarbons relevant to plasma

    Science.gov (United States)

    Singh, Suvam; Antony, Bobby

    2018-05-01

    This article explores positron scattering cross sections by simple hydrocarbons such as ethane, ethene, ethyne, propane, and propyne. Chemical erosion processes occurring on the surface due to plasma-wall interactions are an abundant source of hydrocarbon molecules which contaminate the hydrogenic plasma. These hydrocarbons play an important role in the edge plasma region of Tokamak and ITER. In addition to this, they are also one of the major components in the planetary atmospheres and astrophysical mediums. The present work focuses on calculation of different positron impact interactions with simple hydrocarbons in terms of the total cross section (Qtot), elastic cross section (Qel), direct ionization cross section (Qion), positronium formation cross section (Qps), and total ionization cross section (Qtion). Knowing that the positron-plasma study is one of the trending fields, the calculated data have diverse plasma and astrophysical modeling applications. A comprehensive study of Qtot has been provided where the inelastic cross sections have been reported for the first time. Comparisons are made with those available from the literature, and a good agreement is obtained with the measurements.

  8. Neutron standard cross sections in reactor physics - Need and status

    International Nuclear Information System (INIS)

    Carlson, A.D.

    1990-01-01

    The design and improvement of nuclear reactors require detailed neutronics calculations. These calculations depend on comprehensive libraries of evaluated nuclear cross sections. Most of the cross sections that form the data base for these evaluations have been measured relative to neutron cross-section standards. The use of these standards can often simplify the measurement process by eliminating the need for a direct measurement of the neutron fluence. The standards are not known perfectly, however; thus the accuracy of a cross-section measurement is limited by the uncertainty in the standard cross section relative to which it is measured. Improvements in a standard cause all cross sections measured relative to that standard to be improved. This is the reason for the emphasis on improving the neutron cross-section standards. The continual process of measurement and evaluation has led to improvements in the accuracy and range of applicability of the standards. Though these improvements have been substantial, this process must continue in order to obtain the high-quality standards needed by the user community

  9. Evaluation of kerma in carbon and the carbon cross sections

    International Nuclear Information System (INIS)

    Axton, E.J.

    1992-02-01

    A preliminary simultaneous least squares fit to measurements of kerma in carbon, and carbon cross sections taken from the ENDF/B-V file was carried out. In the calculation the shapes of the total cross section and the various partial cross sections were rigid but their absolute values were allowed to float in the fit within the constraints of the ENDF/B-V uncertainties. The construction of the ENDF/B-V file imposed improbable shapes, particularly in the case of the (12)C(n,n'3(alpha)) reaction, which were incompatible with direct measurements of kerma and of the reaction cross sections. Consequently a new evaluation of the cross section data became necessary. Since the available time was limited the new evaluation concentrated particularly on those aspects of the ENDF/B-V carbon file which would have most impact on kerma calculations. Following the new evaluation of cross sections new tables of kerma factors were produced. Finally, the simultaneous least squares fit to measurements of kerma and the new cross section file was repeated

  10. Pion double charge exchange on 16O at Tπ=300--500 MeV

    International Nuclear Information System (INIS)

    Beatty, D.P.; Burleson, G.R.; Rawool-Sullivan, M.; El-Ghossain, M.; Fortune, H.T.; Williams, A.L.; Smith, D.A.; Morris, C.L.; Garnett, R.; Watson, D.L.; Johnson, J.; Ward, H.; Whitley, C.; Matthews, S.K.; Palarczyk, M.; Edwards, C.; Espy, M.; Hashimoto, O.; Tomoyuki, H.

    1993-01-01

    Measurements of small-angle cross sections for the pion double-charge-exchange (DCX) reaction 16 O(π + ,π - ) 16 Ne (g.s.) at incident energies of 300--500 MeV are reported. These are the first measurements of DCX cross sections on a T=0 nucleus in this energy region. The behavior of the cross sections is similar to that of analog transitions, but they are smaller by more than an order of magnitude. This suggests sequential charge-exchange scattering as the dominant process, but suppressed by a mechanism not yet identified

  11. Effects of cross-section on mechanical properties of Au nanowire

    Energy Technology Data Exchange (ETDEWEB)

    Vazinishayan, Ali; Yang, Shuming, E-mail: shuming.yang@mail.xjtu.edu.cn; Duongthipthewa, Anchalee; Wang, Yiming [State Key Laboratory for manufacturing system engineering, Xi’an Jiaotong University, Xi’an, 710049 (China)

    2016-02-15

    The aim of this paper is study of the effects of multiple cross-section of Au nanowire on mechanical properties. Different cross-section models of Au nanowires including circular, hexagonal, pentagonal and rectangular were simulated by finite element modeling using ABAQUS. In this study, the bending technique was applied so that both ends of the model were clamped with mid-span under loading condition. The cross-sections had the length of 400 nm and the diameter of 40 nm, except the circular cross-section while the rest of the cross-sections had an equivalent diameter. Von Misses stresses distribution were used to define the stress distribution in the cross-section under loading condition, and elastic deformation was analyzed by the beam theory. The results disclosed that the circular and the rectangular models had highest and lowest strengths against plastic deformation, respectively.

  12. Invisible anti-cloak with elliptic cross section using phase complement

    International Nuclear Information System (INIS)

    Yang Yu-Qi; Zhang Min; Yue Jian-Xiang

    2011-01-01

    Based on the theory of phase complement, an anti-cloak with circular cross section can be made invisible to an object outside its domain. As the cloak with elliptic cross section is more effective to make objects invisible than that with circular cross section, a scaled coordinate system is proposed to design equivalent materials of invisible anti-cloak with elliptic cross section using phase complement. The cloaks with conventional dielectric and double negative parameters are both simulated with the geometrical transformations. The results show that the cloak with elliptic cross section through phase complement can effectively hide the outside objects. (classical areas of phenomenology)

  13. Methods for calculating anisotropic transfer cross sections

    International Nuclear Information System (INIS)

    Cai, Shaohui; Zhang, Yixin.

    1985-01-01

    The Legendre moments of the group transfer cross section, which are widely used in the numerical solution of the transport calculation can be efficiently and accurately constructed from low-order (K = 1--2) successive partial range moments. This is convenient for the generation of group constants. In addition, a technique to obtain group-angle correlation transfer cross section without Legendre expansion is presented. (author)

  14. Photoionization cross sections: present status and future needs

    International Nuclear Information System (INIS)

    Manson, S.T.

    1988-01-01

    The existing experimental data situation for photoionization cross section of ground-state atoms, excited states and positive ions is reviewed. The ability of theory to predict these cross sections is also discussed. The likely progress for the near future is presented [pt

  15. Neutrino-nucleus cross sections for oscillation experiments

    Science.gov (United States)

    Katori, Teppei; Martini, Marco

    2018-01-01

    Neutrino oscillations physics is entering an era of high precision. In this context, accelerator-based neutrino experiments need a reduction in systematic errors to the level of a few percent. Today, one of the most important sources of systematic errors are neutrino-nucleus cross sections which, in the energy region of hundreds of MeV to a few GeV, are known to a precision not exceeding 20%. In this article we review the present experimental and theoretical knowledge of neutrino-nucleus interaction physics. After introducing neutrino-oscillation physics and accelerator-based neutrino experiments, we give an overview of general aspects of neutrino-nucleus cross sections, from both the theoretical and experimental point of view. Then, we focus on these cross sections in different reaction channels. We start with the quasi-elastic and quasi-elastic-like cross section, placing a special emphasis on the multinucleon emission channel, which has attracted a lot of attention in the last few years. We review the main aspects of the different microscopic models for this channel by discussing analogies and the differences among them. The discussion is always driven by a comparison with the experimental data. We then consider the one-pion production channel where agreement between data and theory remains highly unsatisfactory. We describe how to interpret pion data, and then analyze, in particular, the puzzle related to the difficulty of theoretical models and Monte Carlo to simultaneously describe MiniBooNE and MINERvA experimental results. Inclusive cross sections are also discussed, as well as the comparison between the {ν }μ and {ν }e cross sections, relevant for the charge-conjugation-parity violation experiments. The impact of nuclear effects on the reconstruction of neutrino energy and on the determination of the neutrino-oscillation parameters is also reviewed. Finally, we look to the future by discussing projects and efforts in relation to future detectors, beams

  16. Inclined Bodies of Various Cross Sections at Supersonic Speeds

    Science.gov (United States)

    Jorgensen, Leland H.

    1958-01-01

    To aid in assessing effects of cross-sectional shape on body aerodynamics, the forces and moments have been measured for bodies with circular, elliptic, square, and triangular cross sections at Mach numbers 1.98 and 3.88. Results for bodies with noncircular cross sections have been compared with results for bodies of revolution having the same axial distribution of cross-sectional area (and, thus, the same equivalent fineness ratio). Comparisons have been made for bodies of fineness ratios 6 and 10 at angles of attack from 0 deg to about 20 deg and for Reynolds numbers, based on body length, of 4.0 x 10(exp 6) and 6.7 x 10(exp 6). The results of this investigation show that distinct aerodynamic advantages can be obtained by using bodies with noncircular cross sections. At certain angles of bank, bodies with elliptic, square, and triangular cross sections develop considerably greater lift and lift-drag ratios than equivalent bodies of revolution. For bodies with elliptic cross sections, lift and pitching-moment coefficients can be correlated with corresponding coefficients for equivalent circular bodies. It has been found that the ratios of lift and pitching-moment coefficients for an elliptic body to those for an equivalent circular body are practically constant with change in both angle of attack and Mach number. These lift and moment ratios are given very accurately by slender-body theory. As a result of this agreement, the method of NACA Rep. 1048 for computing forces and moments for bodies of revolution has been simply extended to bodies with elliptic cross sections. For the cases considered (elliptic bodies of fineness ratios 6 and 10 having cross-sectional axis ratios of 1.5 and 2), agreement of theory with experiment is very good. As a supplement to the force and moment results, visual studies of the flow over bodies have been made by use of the vapor-screen, sublimation, and white-lead techniques. Photographs from these studies are included in the report.

  17. Priority cross-sections. Joint Nordic analyses of important cross-sections in the Nordel system. Main report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-06-01

    The Nordic Grid Master Plan 2002 shed light on the energy and power balance for the Nordel area but with special focus on 2005. There was a lot to suggest that the tradi-tional transport patterns with frequent southbound transports would change and be more frequently replaced by northbound transports. Against this background, a number of cross-sections were identified within the Nordel area where expansion is expected to have considerable significance for the Nordic elec-tricity market. The present report 'Priority Cross-sections' concludes the work which was started with the grid master plan. The priority cross-sections are subjected to a technical and socio-economic analysis. The analysis aims to understand the transports in the Nordel system and to support Nor-del when prioritizing forthcoming initiatives. The market price is the driving force for the initiatives which will be carried out on the supply and demand side. The commissioning and decommissioning of commercial pro-duction capacity is determined by the market players, and the task of the transmission system operators (TSOs) is to ensure a robust infrastructure for the smooth operation of the electricity market. (au)

  18. Measurement of actinide neutron cross sections

    International Nuclear Information System (INIS)

    Firestone, Richard B.; Nitsche, Heino; Leung, Ka-Ngo; Perry, DaleL.; English, Gerald

    2003-01-01

    The maintenance of strong scientific expertise is critical to the U.S. nuclear attribution community. It is particularly important to train students in actinide chemistry and physics. Neutron cross-section data are vital components to strategies for detecting explosives and fissile materials, and these measurements require expertise in chemical separations, actinide target preparation, nuclear spectroscopy, and analytical chemistry. At the University of California, Berkeley and the Lawrence Berkeley National Laboratory we have trained students in actinide chemistry for many years. LBNL is a leader in nuclear data and has published the Table of Isotopes for over 60 years. Recently, LBNL led an international collaboration to measure thermal neutron capture radiative cross sections and prepared the Evaluated Gamma-ray Activation File (EGAF) in collaboration with the IAEA. This file of 35, 000 prompt and delayed gamma ray cross-sections for all elements from Z=1-92 is essential for the neutron interrogation of nuclear materials. LBNL has also developed new, high flux neutron generators and recently opened a 1010 n/s D+D neutron generator experimental facility

  19. 238U subthreshold neutron induced fission cross section

    International Nuclear Information System (INIS)

    Difilippo, F.C.; Perez, R.B.; De Saussure, G.; Olsen, D.K.; Ingle, R.W.

    1976-01-01

    High resolution measurements of the 238 U neutron induced fission cross section are reported for neutron energies between 600 eV and 2 MeV. The average subthreshold fission cross section between 10 and 100 keV was found to be 44 +- 6 μb

  20. Fission cross sections in the intermediate energy region

    International Nuclear Information System (INIS)

    Lisowski, P.W.; Gavron, A.; Parker, W.E.; Ullmann, J.L.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

    1991-01-01

    Until recently there has been very little cross section data for neutron-induced fission in the intermediate energy region, primarily because no suitable neutron source has existed. At Los Alamos, the WNR target-4 facility provides a high-intensity source of neutrons nearly ideal for fission measurements extending from a fraction of a MeV to several hundred MeV. This paper summarizes the status of fission cross section data in the intermediate energy range (En > 30 MeV) and presents our fission cross section data for 235 U and 238 U compared to intranuclear cascade and statistical model predictions

  1. Fission cross sections in the intermediate energy region

    Energy Technology Data Exchange (ETDEWEB)

    Lisowski, P.W.; Gavron, A.; Parker, W.E.; Ullmann, J.L.; Balestrini, S.J. (Los Alamos National Lab., NM (USA)); Carlson, A.D.; Wasson, O.A. (National Inst. of Standards and Technology, Gaithersburg, MD (USA)); Hill, N.W. (Oak Ridge National Lab., TN (USA))

    1991-01-01

    Until recently there has been very little cross section data for neutron-induced fission in the intermediate energy region, primarily because no suitable neutron source has existed. At Los Alamos, the WNR target-4 facility provides a high-intensity source of neutrons nearly ideal for fission measurements extending from a fraction of a MeV to several hundred MeV. This paper summarizes the status of fission cross section data in the intermediate energy range (En > 30 MeV) and presents our fission cross section data for {sup 235}U and {sup 238}U compared to intranuclear cascade and statistical model predictions.

  2. Polynomial parameterized representation of macroscopic cross section for PWR reactor

    International Nuclear Information System (INIS)

    Fiel, Joao Claudio B.

    2015-01-01

    The purpose of this work is to describe, by means of Tchebychev polynomial, a parameterized representation of the homogenized macroscopic cross section for PWR fuel element as a function of soluble boron concentration, moderator temperature, fuel temperature, moderator density and 235 U 92 enrichment. Analyzed cross sections are: fission, scattering, total, transport, absorption and capture. This parameterization enables a quick and easy determination of the problem-dependent cross-sections to be used in few groups calculations. The methodology presented here will enable to provide cross-sections values to perform PWR core calculations without the need to generate them based on computer code calculations using standard steps. The results obtained by parameterized cross-sections functions, when compared with the cross-section generated by SCALE code calculations, or when compared with K inf , generated by MCNPX code calculations, show a difference of less than 0.7 percent. (author)

  3. Damage energy and displacement cross sections: survey and sensitivity

    International Nuclear Information System (INIS)

    Doran, D.G.; Parkin, D.M.; Robinson, M.T.

    1976-10-01

    Calculations of damage energy and displacement cross sections using the recommendations of a 1972 IAEA Specialists' Meeting are reviewed. The sensitivity of the results to assumptions about electronic energy losses in cascade development and to different choices respecting the nuclear cross sections is indicated. For many metals, relative uncertainties and sensitivities in these areas are sufficiently small that adoption of standard displacement cross sections for neutron irradiations can be recommended

  4. Cross section recondensation method via generalized energy condensation theory

    International Nuclear Information System (INIS)

    Douglass, Steven; Rahnema, Farzad

    2011-01-01

    Highlights: → A new method is presented which corrects for core environment error from specular boundaries at the lattice cell level. → Solution obtained with generalized energy condensation provides improved approximation to the core level fine-group flux. → Iterative recondensation of the cross sections and unfolding of the flux provides on-the-fly updating of the core cross sections. → Precomputation of energy integrals and fine-group cross sections allows for easy implementation and efficient solution. → Method has been implemented in 1D and shown to correct the environment error, particularly in strongly heterogeneous cores. - Abstract: The standard multigroup method used in whole-core reactor analysis relies on energy condensed (coarse-group) cross sections generated from single lattice cell calculations, typically with specular reflective boundary conditions. Because these boundary conditions are an approximation and not representative of the core environment for that lattice, an error is introduced in the core solution (both eigenvalue and flux). As current and next generation reactors trend toward increasing assembly and core heterogeneity, this error becomes more significant. The method presented here corrects for this error by generating updated coarse-group cross sections on-the-fly within whole-core reactor calculations without resorting to additional cell calculations. In this paper, the fine-group core flux is unfolded by making use of the recently published Generalized Condensation Theory and the cross sections are recondensed at the whole-core level. By iteratively performing this recondensation, an improved core solution is found in which the core-environment has been fully taken into account. This recondensation method is both easy to implement and computationally very efficient because it requires precomputation and storage of only the energy integrals and fine-group cross sections. In this work, the theoretical basis and development

  5. Poster - 18: New features in EGSnrc for photon cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Elsayed; Mainegra-Hing, Ernesto; Rogers, David W.O. [The Ottawa Hospital Cancer Centre, National Research Council Canada, Carleton University (Canada)

    2016-08-15

    Purpose: To implement two new features in the EGSnrc Monte Carlo system. The first is an option to account for photonuclear attenuation, which can contribute a few percent to the total cross section at the higher end of the energy range of interest to medical physics. The second is an option to use exact NIST XCOM photon cross sections. Methods: For the first feature, the photonuclear total cross sections are generated from the IAEA evaluated data. In the current, first-order implementation, after a photonuclear event, there is no energy deposition or secondary particle generation. The implementation is validated against deterministic calculations and experimental measurements of transmission signals. For the second feature, before this work, if the user explicitly requested XCOM photon cross sections, EGSnrc still used its own internal incoherent scattering cross sections. These differ by up to 2% from XCOM data between 30 keV and 40 MeV. After this work, exact XCOM incoherent scattering cross sections are an available option. Minor interpolation artifacts in pair and triplet XCOM cross sections are also addressed. The default for photon cross section in EGSnrc is XCOM except for the new incoherent scattering cross sections, which have to be explicitly requested. The photonuclear, incoherent, pair and triplet data from this work are available for elements and compounds for photon energies from 1 keV to 100 GeV. Results: Both features are implemented and validated in EGSnrc.Conclusions: The two features are part of the standard EGSnrc distribution as of version 4.2.3.2.

  6. MINERvA - neutrino nucleus cross section experiment

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    Recent results from MINERvA, a neutrino cross section experiment at Fermilab, are presented. MINERVA has the goal of providing precision results which will have important impact on oscillation experiments.  Initial data runs for muon neutrino and antineutrino beams of ~3.5 GeV have produced a large number of new results. This seminar will introduce the experiment and describe results for quasielastic, pion production, and inclusive cross sections.

  7. Evaluation methods for neutron cross section standards

    International Nuclear Information System (INIS)

    Bhat, M.R.

    1980-01-01

    Methods used to evaluate the neutron cross section standards are reviewed and their relative merits, assessed. These include phase-shift analysis, R-matrix fit, and a number of other methods by Poenitz, Bhat, Kon'shin and the Bayesian or generalized least-squares procedures. The problems involved in adopting these methods for future cross section standards evaluations are considered, and the prospects for their use, discussed. 115 references, 5 figures, 3 tables

  8. Evaluation of cross sections for neutron-induced reactions in sodium

    International Nuclear Information System (INIS)

    Larson, D.C.

    1980-09-01

    An evaluation of the neutron-induced cross sections of 23 Na has been done for the energy range from 10 -5 eV to 20 MeV. All significant cross sections are given, including differential cross sections for production of gamma rays. The recommended values are based on experimental data where available, and use results of a consistent model code analysis of available data to predict cross sections where there are no experimental data. This report describes the evaluation that was submitted to the Cross Section Evaluation Working Group (CSEWG) for consideration as a part of the Evaluated Nuclear Data File, Version V, and subsequently issued as MAT 1311. 126 references, 130 figures, 14 tables

  9. Bent solenoids for spectrometers and emittance exchange sections

    International Nuclear Information System (INIS)

    Norem, J.

    1999-01-01

    Bent solenoids can be used to transport low energy beams as they provide both confinement and dispersion of particle orbits. Solenoids are being considered both as emittance exchange sections and spectrometers in the muon cooling system as part of the study of the muon collider. They present the results of a study of bent solenoids which considers the design of coupling sections between bent solenoids to straight solenoids, drift compensation fields, aberrations, and factors relating to the construction, such as field ripple, stored energy, coil forces and field errors

  10. Positron total scattering cross-sections for alkali atoms

    Science.gov (United States)

    Sinha, Nidhi; Singh, Suvam; Antony, Bobby

    2018-01-01

    Positron-impact total scattering cross-sections for Li, Na, K, Rb, Cs and Fr atoms are calculated in the energy range from 5-5000 eV employing modified spherical complex optical potential formalism. The main aim of this work is to apply this formalism to the less studied positron-target collision systems. The results are compared with previous theoretical and experimental data, wherever available. In general, the present data show overall agreement and consistency with other results. Furthermore, we have done a comparative study of the results to investigate the effect of atomic size on the cross-sections as we descend through the group in the periodic table. We have also plotted a correlation graph of the present total cross-sections with polarizability and number of target electrons. The two correlation plots confirm the credibility and consistency of the present results. Besides, this is the first theoretical attempt to report positron-impact total cross-sections of alkali atoms over such a wide energy range.

  11. Rapidity gap cross sections measured with the ATLAS detector in pp collisions at sqrt{s} = 7 TeV

    Czech Academy of Sciences Publication Activity Database

    Aad, G.; Abbott, B.; Abdallah, J.; Chudoba, Jiří; Gallus, Petr; Gunther, Jaroslav; Hruška, I.; Juránek, Vojtěch; Kepka, Oldřich; Kupčo, Alexander; Kůs, Vlastimil; Lipinský, L.; Lokajíček, Miloš; Marčišovský, Michal; Mikeštíková, Marcela; Myška, Miroslav; Němeček, Stanislav; Panušková, M.; Růžička, Pavel; Schovancová, Jaroslava; Šícho, Petr; Staroba, Pavel; Svatoš, Michal; Taševský, Marek; Tic, Tomáš; Valenta, J.; Vrba, Václav; Zeman, Martin

    2012-01-01

    Roč. 72, č. 3 (2012), s. 1-20 ISSN 1434-6044 R&D Projects: GA MŠk LA08032 Institutional research plan: CEZ:AV0Z10100502 Keywords : ATLAS * LHC * rapidity gap * differential cross section * pomeron exchange * hadronproduction * triple-Regge limit * diffraction Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 5.247, year: 2012 http://arxiv.org/abs/arXiv:1201.2808

  12. pp production cross sections and the constraint method

    International Nuclear Information System (INIS)

    Anjos, J.C.; Santoro, A.F.S.; Souza, M.H.G.

    1983-01-01

    A method of constructing production cross sections that satisfy the constraints represented by the first few moments is shown to give an excellent account of the data when applied to the high energy pp production cross section ν sub(n) (s) plotted as functions of n. (Author) [pt

  13. Total Cross Sections at High Energies An update

    CERN Document Server

    Fazal-e-Aleem, M; Alam, Saeed; Qadee-Afzal, M

    2002-01-01

    Current and Future measurements for the total cross sections at E-811, PP2PP, CSM, FELIX and TOTEM have been analyzed using various models. In the light of this study an attempt has been made to focus on the behavior of total cross section at very high energies.

  14. Measurement and QCD Analysis of the Diffractive Deep-Inelastic Scattering Cross Section at HERA

    CERN Document Server

    Aktas, A.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boenig, M.O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J.G.; Coughlan, J.A.; Coppens, Y.R.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; de Boer, Y.; Delcourt, B.; Del Degan, M.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Flucke, G.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, S.; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B.R.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Henderson, R.C.W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, C.L.; Johnson, D.P.; Jung, A.W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.I.; Lueders, H.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Marage, P.; Marshall, R.; Marti, L.; Martisikova, M.; Martyn, H.U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, M.U.; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, T.; Newman, P.R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G.D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Portheault, B.; Povh, B.; Prideaux, P.; Rahmat, A.J.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schilling, F.P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Stiewe, J.; Stoilov, A.; Straumann, U.; Sunar, D.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Urban, M.; Usik, A.; Utkin, D.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wessling, B.; Wissing, C.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

    2006-01-01

    A detailed analysis is presented of the diffractive deep-inelastic scattering process $ep\\to eXY$, where $Y$ is a proton or a low mass proton excitation carrying a fraction $1 - \\xpom > 0.95$ of the incident proton longitudinal momentum and the squared four-momentum transfer at the proton vertex satisfies $|t|<1 {\\rm GeV^2}$. Using data taken by the H1 experiment, the cross section is measured for photon virtualities in the range $3.5 \\leq Q^2 \\leq 1600 \\rm GeV^2$, triple differentially in $\\xpom$, $Q^2$ and $\\beta = x / \\xpom$, where $x$ is the Bjorken scaling variable. At low $\\xpom$, the data are consistent with a factorisable $\\xpom$ dependence, which can be described by the exchange of an effective pomeron trajectory with intercept $\\alphapom(0)= 1.118 \\pm 0.008 {\\rm (exp.)} ^{+0.029}_{-0.010} {\\rm (model)}$. Diffractive parton distribution functions and their uncertainties are determined from a next-to-leading order DGLAP QCD analysis of the $Q^2$ and $\\beta$ dependences of the cross section. The res...

  15. Pion-nucleus cross sections approximation

    International Nuclear Information System (INIS)

    Barashenkov, V.S.; Polanski, A.; Sosnin, A.N.

    1990-01-01

    Analytical approximation of pion-nucleus elastic and inelastic interaction cross-section is suggested, with could be applied in the energy range exceeding several dozens of MeV for nuclei heavier than beryllium. 3 refs.; 4 tabs

  16. Electron collision cross section sets of TMS and TEOS vapours

    Science.gov (United States)

    Kawaguchi, S.; Takahashi, K.; Satoh, K.; Itoh, H.

    2017-05-01

    Reliable and detailed sets of electron collision cross sections for tetramethylsilane [TMS, Si(CH3)4] and tetraethoxysilane [TEOS, Si(OC2H5)4] vapours are proposed. The cross section sets of TMS and TEOS vapours include 16 and 20 kinds of partial ionization cross sections, respectively. Electron transport coefficients, such as electron drift velocity, ionization coefficient, and longitudinal diffusion coefficient, in those vapours are calculated by Monte Carlo simulations using the proposed cross section sets, and the validity of the sets is confirmed by comparing the calculated values of those transport coefficients with measured data. Furthermore, the calculated values of the ionization coefficient in TEOS/O2 mixtures are compared with measured data to confirm the validity of the proposed cross section set.

  17. 26 CFR 1.356-4 - Exchanges for section 306 stock.

    Science.gov (United States)

    2010-04-01

    ... exchange for section 306 stock, an amount equal to the fair market value of the property plus the money, if... of common stock having a fair market value of $80 and one $100 bond having a fair market value of... a distribution to which section 301 is applicable to the extent of its entire fair market value...

  18. Production cross sections and momentum distributions of the projectile fragments of a 500 MeV/u 86Kr beam

    International Nuclear Information System (INIS)

    Weber, M.

    1993-07-01

    The projectile fragmentation of a 500 MeV/u 86 Kr beam in a beryllium, copper, respectively tantalum target was studied at the projectile-fragment separator of the GSI. The new neutron-rich isotopes 58 Ti, 61 V, 63 Cr, 66 Mn, 69 Fe, and 71 Co could be uniquely identified, furthermore a hint on the existence of 64 Cr, 72 Co, and 75 Ni resulted. The experimental production cross sections, which were determined for a large A and Z range, were compared with the predictions of three different models. The studies presented in the present thesis allow an extrapolation of the production cross section for the double-magic nucleus 78 Ni of only 0.6 pb. With increasing nuclear-charge number of the target material a larger production cross section for light fragments was observed. From these data it can be concluded that projectile-like fragments arise in peripheral and light fragments in central reactions. Furthermore production cross sections and parallel momentum distributions of the rubidium isotopes and the 86 Br were measured. To the experimentally observed charge-exchange products two possible processes can be assigned, namely the quasi-free nucleon-nucleon collision respectively the excitation of a Δresonance. (HSI)

  19. Hydrogen/deuterium exchange of cross-linkable alpha-amino acid derivatives in deuterated triflic acid

    OpenAIRE

    Wang, Lei; Murai, Yuta; Yoshida, Takuma; Okamoto, Masashi; Masuda, Katsuyoshi; Sakihama, Yasuko; Hashidoko, Yasuyuki; Hatanaka, Yasumaru; Hashimoto, Makoto

    2014-01-01

    In this paper we report here a hydrogen/deuterium exchange (H/D exchange) of cross-linkable alpha-amino acid derivatives with deuterated trifluoromethanesulfonic acid (TfOD). H/D exchange with TfOD was easily applied to o-catechol containing phenylalanine (DOPA) within an hour. A partial H/D exchange was observed for trifluoromethyldiazirinyl (TFMD) phenylalanine derivatives. N-Acetyl-protected natural aromatic alpha-amino acids (Tyr and Trp) were more effective in H/D exchange than unprotect...

  20. LINEAR2007, Linear-Linear Interpolation of ENDF Format Cross-Sections

    International Nuclear Information System (INIS)

    2007-01-01

    1 - Description of program or function: LINEAR converts evaluated cross sections in the ENDF/B format into a tabular form that is subject to linear-linear interpolation in energy and cross section. The code also thins tables of cross sections already in that form. Codes used subsequently need thus to consider only linear-linear data. IAEA1311/15: This version include the updates up to January 30, 2007. Changes in ENDF/B-VII Format and procedures, as well as the evaluations themselves, make it impossible for versions of the ENDF/B pre-processing codes earlier than PREPRO 2007 (2007 Version) to accurately process current ENDF/B-VII evaluations. The present code can handle all existing ENDF/B-VI evaluations through release 8, which will be the last release of ENDF/B-VI. Modifications from previous versions: - Linear VERS. 2007-1 (JAN. 2007): checked against all ENDF/B-VII; increased page size from 60,000 to 600,000 points 2 - Method of solution: Each section of data is considered separately. Each section of File 3, 23, and 27 data consists of a table of cross section versus energy with any of five interpolation laws. LINEAR will replace each section with a new table of energy versus cross section data in which the interpolation law is always linear in energy and cross section. The histogram (constant cross section between two energies) interpolation law is converted to linear-linear by substituting two points for each initial point. The linear-linear is not altered. For the log-linear, linear-log and log- log laws, the cross section data are converted to linear by an interval halving algorithm. Each interval is divided in half until the value at the middle of the interval can be approximated by linear-linear interpolation to within a given accuracy. The LINEAR program uses a multipoint fractional error thinning algorithm to minimize the size of each cross section table

  1. Measurement of the differential and total cross sections of the γ d →K0Λ (p ) reaction within the resonance region

    Science.gov (United States)

    Compton, N.; Taylor, C. E.; Hicks, K.; Cole, P.; Zachariou, N.; Ilieva, Y.; Nadel-Turonski, P.; Klempt, E.; Nikonov, V. A.; Sarantsev, A. V.; Adhikari, K. P.; Adhikari, S.; Akbar, Z.; Anefalos Pereira, S.; Avakian, H.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Camp, M.; Cao, Frank Thanh; Cao, T.; Carman, D. S.; Celentano, A.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Fradi, A.; Gavalian, G.; Ghandilyan, Y.; Giovanetti, K. L.; Girod, F. X.; Glazier, D. I.; Gleason, C.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Heddle, D.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khachatryan, G.; Khachatryan, M.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; McKinnon, B.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Murdoch, G.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Raue, B. A.; Ripani, M.; Ritchie, B. G.; Rizzo, A.; Rosner, G.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stankovic, I.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Torayev, B.; Trivedi, A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Wood, M. H.; Zachariou, N.; Zhang, J.; CLAS Collaboration

    2017-12-01

    We report the first measurement of differential and total cross sections for the γ d →K0Λ (p ) reaction, using data from the CLAS detector at the Thomas Jefferson National Accelerator Facility. Data collected during two separate experimental runs were studied with photon-energy coverage 0.8-3.6 GeV and 0.5- 2.6 GeV, respectively. The two measurements are consistent giving confidence in the method and determination of systematic uncertainties. The cross sections are compared with predictions from the KAON-MAID theoretical model (without kaon exchange), which deviate from the data at higher W and at forward kaon angles. These data, along with previously published cross sections for K+Λ photoproduction, provide essential constraints on the nucleon resonance spectrum. A first partial wave analysis was performed that describes the data without the introduction of new resonances.

  2. A method for measuring light ion reaction cross-sections

    International Nuclear Information System (INIS)

    Carlson, R.F.; Ingemarsson, A.; Lantz, M.; Arendse, G.J.; Auce, A.; Cox, A.J.; Foertsch, S.V.; Jacobs, N.M.; Johansson, R.; Nyberg, J.; Peavy, J.; Renberg, P.-U.; Sundberg, O.; Stander, J.A.; Steyn, G.F.; Tibell, G.; Zorro, R.

    2005-01-01

    An experimental procedure for measuring reaction cross-sections of light ions in the energy range 20-50 MeV/nucleon, using a modified attenuation technique, is described. The detection method incorporates a forward detector that simultaneously measures the reaction cross-sections for five different sizes of the solid angle in steps from 99.1% to 99.8% of the total solid angle. The final reaction cross-section values are obtained by extrapolation to the full solid angle

  3. A method for measuring light ion reaction cross sections

    International Nuclear Information System (INIS)

    Carlson, R.F.; Ingemarsson, A.; Lantz, M.

    2005-03-01

    An experimental procedure for measuring reaction cross sections of light ions in the energy range 20-50 MeV/nucleon, using a modified attenuation technique, is described. The detection method incorporates a forward detector that simultaneously measures the reaction cross sections for five different sizes of the solid angles in steps from 99.1 to 99.8% of the total solid angle. The final reaction cross section values are obtained by extrapolation to the full solid angle

  4. Calculated Cross Sections for the Electron Impact Ionization of Molecular Ions

    Science.gov (United States)

    Deutsch, H.; Becker, K.; Defrance, P.; Onthong, U.; Parajuli, R.; Probst, M.; Matt-Leubner, S.; Maerk, T.

    2002-10-01

    We report the results of the application of the semi- classical Deutsch-Märk (DM) formalism to the calculation of the absolute electron-impact ionization cross section of the molecular ions H2+, N2+, O2+, CD+, CO+, CO2+, H3O+, and CH4+ for which experimental data have been reported . Where available, we also compare our calculated cross sections with calculated cross sections using the BEB method of Kim and co-workers. The level of agreement between the experimentally determined and calculated cross section is satisfactory in some cases. In all cases, the calculated cross sections exceed the measured cross sections which is not surprising in view of the experimental complications in measuring ionization cross sections of molecular ions due to the presence of competing channels such as ionization dissociative ionization, and dissociative excitation. Work supported in part by FWF, OEAW, and NASA.

  5. Meeting cross-section requirements for nuclear-energy design

    Energy Technology Data Exchange (ETDEWEB)

    Weisbin, C.R.; de Saussure, G.; Santoro, R.T. (Oak Ridge National Lab., TN (USA)); Gilai, T. (Ben-Gurion Univ. of the Negev, Beersheba (Israel))

    1982-01-01

    Current requirements in cross-section data that are essential to nuclear-energy programmes are summarized and explained and some insight into how these data might be obtained is provided. The six sections of the paper describe: design parameters and target accuracies; data collection, evaluation and analysis; determination of high-accuracy differential nuclear data for technological applications; status of selected evaluated nuclear data; analysis of benchmark testing; identification of important cross sections and inferred needs.

  6. Neutron Elastic Scattering Cross Sections Experimental Data and Optical Model Cross Section Calculations. A Compilation of Neutron Data from the Studsvik Neutron Physics Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Holmqvist, B; Wiedling, T

    1969-06-15

    Neutron elastic scattering cross section measurements have been going on for a long period at the Studsvik Van de Graaff laboratory. The cross sections of a range of elements have been investigated in the energy interval 1.5 to 8 MeV. The experimental data have been compared with cross sections calculated with the optical model when using a local nuclear potential.

  7. Systematics of fission cross sections at the intermediate energy region

    Energy Technology Data Exchange (ETDEWEB)

    Fukahori, Tokio; Chiba, Satoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    The systematics was obtained with fitting experimental data for proton induced fission cross sections of Ag, {sup 181}Ta, {sup 197}Au, {sup 206,207,208}Pb, {sup 209}Bi, {sup 232}Th, {sup 233,235,238}U, {sup 237}Np and {sup 239}Pu above 20 MeV. The low energy cross section of actinoid nuclei is omitted from systematics study, since the cross section has a complicated shape and strongly depends on characteristic of nucleus. The fission cross sections calculated by the systematics are in good agreement with experimental data. (author)

  8. Total cross-section measurements progress in nuclear physics

    CERN Document Server

    Giacomelli, G; Mulvey, J H

    2013-01-01

    Total Cross-Section Measurements discusses the cross-sectional dimensions of elementary hadron collisions. The main coverage of the book is the resonance and high energy area of the given collision. A section of the book explains in detail the characteristic of a resonance region. Another section is focused on the location of the high energy region of collision. Parts of the book define the meaning of resonance in nuclear physics. Also explained are the measurement of resonance and the identification of the area where the resonance originates. Different experimental methods to measure the tota

  9. Learning of Cross-Sectional Anatomy Using Clay Models

    Science.gov (United States)

    Oh, Chang-Seok; Kim, Ji-Young; Choe, Yeon Hyeon

    2009-01-01

    We incorporated clay modeling into gross anatomy and neuro-anatomy courses to help students understand cross-sectional anatomy. By making clay models, cutting them and comparing cut surfaces to CT and MR images, students learned how cross-sectional two-dimensional images were created from three-dimensional structure of human organs. Most students…

  10. Q.C.D. estimates of hadronic cross sections

    International Nuclear Information System (INIS)

    Navelet, H.; Peschanski, R.

    1983-03-01

    Estimates for hadron-hadron cross-sections are made using the leading log approximation of Q.C.D. The rise of the total inelastic pp cross-sections at high energy is reproduced, thanks to the competition between the small parton-parton interaction and the large multiplicity of gluons predicted by Q.C.D

  11. Measurements of Electron Proton Elastic Cross Sections for 0.4

    International Nuclear Information System (INIS)

    Christy, M.E.; Abdellah Ahmidouch; Christopher Armstrong; John Arrington; Arshak Asaturyan; Steven Avery; Baker, O.; Douglas Beck; Henk Blok; Bochna, C.W.; Werner Boeglin; Peter Bosted; Maurice Bouwhuis; Herbert Breuer; Brown, D.S.; Antje Bruell; Roger Carlini; Nicholas Chant; Anthony Cochran; Leon Cole; Samuel Danagoulian; Donal Day; James Dunne; Dipangkar Dutta; Rolf Ent; Howard Fenker; Fox, B.; Liping Gan; Haiyan Gao; Kenneth Garrow; David Gaskell; Ashot Gasparian; Don Geesaman; Paul Gueye; Mark Harvey; Roy Holt; Xiaodong Jiang; Cynthia Keppel; Edward Kinney; Yongguang Liang; Wolfgang Lorenzon; Allison Lung; Pete Markowitz; Martin, J.W.; Kevin Mcilhany; David Mckee; David Meekins; Miller, M.A.; Richard Milner; Joseph Mitchell; Hamlet Mkrtchyan; Robert Mueller; Alan Nathan; Gabriel Niculescu; Maria-ioana Niculescu; Thomas O'neill; Vassilios Papavassiliou; Stephen Pate; Rodney Piercey; David Potterveld; Ronald Ransome; Joerg Reinhold; Rollinde, E.; Philip Roos; Adam Sarty; Reyad Sawafta; Elaine Schulte; Edwin Segbefia; Smith, C.; Samuel Stepanyan; Steffen Strauch; Vardan Tadevosyan; Liguang Tang; Raphael Tieulent; Alicia Uzzle; William Vulcan; Stephen Wood; Feng Xiong; Lulin Yuan; Markus Zeier; Benedikt Zihlmann; Vitaliy Ziskin

    2004-01-01

    We report on precision measurements of the elastic cross section for electron-proton scattering performed in Hall C at Jefferson Lab. The measurements were made at 28 distinct kinematic settings covering a range in momentum transfer of 0.4 < Q2 < 5.5 (GeV/c)2. These measurements represent a significant contribution to the world's cross section data set in the Q2 range, where a large discrepancy currently exists between the ratio of electric to magnetic proton form factors extracted from previous cross section measurements and that recently measured via polarization transfer in Hall A at Jefferson Lab. This data set shows good agreement with previous cross section measurements, indicating that if a heretofore unknown systematic error does exist in the cross section measurements, then it is intrinsic to all such measurements

  12. Photoproton cross section for /sup 19/F

    Energy Technology Data Exchange (ETDEWEB)

    Tsubota, H [Tohoku Univ., Sendai (Japan). Coll. of General Education; Kawamura, N; Oikawa, S; Uegaki, J I

    1975-02-01

    Proton energy spectra have been measured at 90/sup 0/ for the /sup 19/F(e,e'p)/sup 18/O reaction in the giant resonance region. The (..gamma..,p/sub 0/) and (..gamma..,p/sub 1/) differential cross sections are extracted from the proton energy spectra by using virtual-photon spectra. The integrated differential cross section of the (..gamma..,p/sub 0/) and (..gamma..,p/sub 1/) reactions are 1.80+-0.27 and 0.50+-0.45 MeV-mb/sr, respectively. The results are discussed with the shell model theory by comparing with the (..gamma..,p/sub 0/) cross section of the neighboring 4n-nucleus /sup 20/Ne. A significant increase of the proton yield leaving the non-ground states is found at 25 MeV of the incident electron energy. This is discussed in terms of the core excitation effect.

  13. Electron-collision cross sections for iodine

    International Nuclear Information System (INIS)

    Zatsarinny, O.; Bartschat, K.; Garcia, G.; Blanco, F.; Hargreaves, L.R.; Jones, D.B.; Murrie, R.; Brunton, J.R.; Brunger, M.J.; Hoshino, M.; Buckman, S.J.

    2011-01-01

    We present results from a joint experimental and theoretical study of elastic electron scattering from atomic iodine. The experimental results were obtained by subtracting known cross sections from the measured data obtained with a pyrolyzed mixed beam containing a variety of atomic and molecular species. The calculations were performed using both a fully relativistic Dirac B-spline R-matrix (close-coupling) method and an optical model potential approach. Given the difficulty of the problem, the agreement between the two sets of theoretical predictions and the experimental data for the angle-differential and the angle-integrated elastic cross sections at 40 eV and 50 eV is satisfactory.

  14. Fission neutron spectrum averaged cross sections for threshold reactions on arsenic

    International Nuclear Information System (INIS)

    Dorval, E.L.; Arribere, M.A.; Kestelman, A.J.; Comision Nacional de Energia Atomica, Cuyo Nacional Univ., Bariloche; Ribeiro Guevara, S.; Cohen, I.M.; Ohaco, R.A.; Segovia, M.S.; Yunes, A.N.; Arrondo, M.; Comision Nacional de Energia Atomica, Buenos Aires

    2006-01-01

    We have measured the cross sections, averaged over a 235 U fission neutron spectrum, for the two high threshold reactions: 75 As(n,p) 75 mGe and 75 As(n,2n) 74 As. The measured averaged cross sections are 0.292±0.022 mb, referred to the 3.95±0.20 mb standard for the 27 Al(n,p) 27 Mg averaged cross section, and 0.371±0.032 mb referred to the 111±3 mb standard for the 58 Ni(n,p) 58m+g Co averaged cross section, respectively. The measured averaged cross sections were also evaluated semi-empirically by numerically integrating experimental differential cross section data extracted for both reactions from the current literature. The calculations were performed for four different representations of the thermal-neutron-induced 235 U fission neutron spectrum. The calculated cross sections, though depending on analytical representation of the flux, agree with the measured values within the estimated uncertainties. (author)

  15. Precise measurements of neutron capture cross sections for FP

    International Nuclear Information System (INIS)

    Nakamura, Shoji; Harada, Hideo; Katoh, Toshio

    2000-01-01

    The thermal neutron capture cross sections (σ 0 ) and the resonance integrals (I 0 ) of some fission products (FP), such as 137 Cs, 90 Sr, 99 Tc, 129 I and 135 Cs, were measured by the activation and γ-ray spectroscopic methods. Moreover, the cross section measurements were done for other FP elements, such as 127 I, 133 Cs and 134 Cs. This paper provides the summary of the FP cross section measurements, which have been performed by authors. (author)

  16. Habit, Production, and the Cross-Section of Stock Returns

    OpenAIRE

    Chen, Andrew Y.

    2014-01-01

    Solutions to the equity premium puzzle should inform us about the cross-section of stock returns. An external habit model with heterogeneous firms reproduces numerous stylized facts about both the equity premium and the value premium. The equity premium is large, time-varying, and linked with consumption volatility. The cross-section of expected returns is log-linear in B/M, and the slope matches the data. The explanation for the value premium lies in the interaction between the cross-section...

  17. Drell-Yan cross section in the jet calculus scheme

    International Nuclear Information System (INIS)

    Tanaka, Hidekazu; Kobayashi, Hirokazu

    2009-01-01

    We calculate factorized cross sections for lepton pair production mediated by a virtual photon in hadron-hadron collisions using the jet calculus scheme, in which a kinematical constraint due to parton radiation is taken into account. This method guarantees a proper phase space boundary for subtraction terms. Some properties of the calculated cross sections are examined. We also discuss matching between the hard scattering cross sections and parton showers at the next-to-leading logarithmic (NLL) order of quantum chromodynamics (QCD). (author)

  18. Testing of cross section libraries for TRIGA criticality benchmark

    International Nuclear Information System (INIS)

    Snoj, L.; Trkov, A.; Ravnik, M.

    2007-01-01

    Influence of various up-to-date cross section libraries on the multiplication factor of TRIGA benchmark as well as the influence of fuel composition on the multiplication factor of the system composed of various types of TRIGA fuel elements was investigated. It was observed that keff calculated by using the ENDF/B VII cross section library is systematically higher than using the ENDF/B-VI cross section library. The main contributions (∼ 2 20 pcm) are from 235 U and Zr. (author)

  19. Cross-section sensitivity analyses for a Tokamak Experimental Power Reactor

    International Nuclear Information System (INIS)

    Simmons, E.L.; Gerstl, S.A.W.; Dudziak, D.J.

    1977-09-01

    The objectives of this report were (1) to determine the sensitivity of neutronic responses in the preliminary design of the Tokamak Experimental Power Reactor by Argonne National Laboratory, and (2) to develop the use of a neutron-gamma coupled cross-section set in the calculation of cross-section sensitivity analysis. Response functions such as neutron plus gamma kerma, Mylar dose, copper transmutation, copper dpa, and activation of the toroidal field coil dewar were investigated. Calculations revealed that the responses were most sensitive to the high-energy group cross sections of iron in the innermost regions containing stainless steel. For example, both the neutron heating of the toroidal field coil and the activation of the toroidal field coil dewar show an integral sensitivity of about -5 with respect to the iron total cross sections. Major contributors are the scattering cross sections of iron, with -2.7 and -4.4 for neutron heating and activation, respectively. The effects of changes in gamma cross sections were generally an order of 10 lower

  20. Evaluation of covariance for 238U cross sections

    International Nuclear Information System (INIS)

    Kawano, Toshihiko; Nakamura, Masahiro; Matsuda, Nobuyuki; Kanda, Yukinori

    1995-01-01

    Covariances of 238 U are generated using analytic functions for representation of the cross sections. The covariances of the (n,2n) and (n,3n) reactions are derived with a spline function, while the covariances of the total and the inelastic scattering cross section are estimated with a linearized nuclear model calculation. (author)

  1. Implementation of the rapid cross section adjustment approach at General Electric

    International Nuclear Information System (INIS)

    Cowan, C.L.; Kujawski, E.; Protsik, R.

    1978-01-01

    The General Electric rapid cross section adjustment approach was developed to use the shielding factor method for formulating multigroup cross sections. In this approach, space- and composition-dependent cross sections for a particular reactor or shield design are prepared from a generalized cross section library by the use of resonance self-shielding factors, and by the adjustment of elastic scattering cross sections for the local neutron flux spectra. The principal tool in the cross section adjustment package is the data processing code TDOWN. This code was specified to give the user a high degree of flexibility in the analysis of advanced reactor designs. Of particular interest in the analysis of critical experiments is the ability to carry out cell heterogeneity self-shielding calculations using a multiregion equivalence relationship, and the homogenization of the cross sections over the specified cell with the flux weighting obtained from transport theory calculations. Extensive testing of the rapid cross section adjustment approach, including comparisons with Monte Carlo methods, indicated that this approach can be utilized with a high degree of confidence in the design analysis of complex fast reactor systems. 2 figures, 1 table

  2. Reference Cross Sections for Charged-particle Monitor Reactions

    Science.gov (United States)

    Hermanne, A.; Ignatyuk, A. V.; Capote, R.; Carlson, B. V.; Engle, J. W.; Kellett, M. A.; Kibédi, T.; Kim, G.; Kondev, F. G.; Hussain, M.; Lebeda, O.; Luca, A.; Nagai, Y.; Naik, H.; Nichols, A. L.; Nortier, F. M.; Suryanarayana, S. V.; Takács, S.; Tárkányi, F. T.; Verpelli, M.

    2018-02-01

    Evaluated cross sections of beam-monitor reactions are expected to become the de-facto standard for cross-section measurements that are performed over a very broad energy range in accelerators in order to produce particular radionuclides for industrial and medical applications. The requirements for such data need to be addressed in a timely manner, and therefore an IAEA coordinated research project was launched in December 2012 to establish or improve the nuclear data required to characterise charged-particle monitor reactions. An international team was assembled to recommend more accurate cross-section data over a wide range of targets and projectiles, undertaken in conjunction with a limited number of measurements and more extensive evaluations of the decay data of specific radionuclides. Least-square evaluations of monitor-reaction cross sections including uncertainty quantification have been undertaken for charged-particle beams of protons, deuterons, 3He- and 4He-particles. Recommended beam monitor reaction data with their uncertainties are available at the IAEA-NDS medical portal http://www-nds.iaea.org/medical/monitor_reactions.html.

  3. Total and partial recombination cross sections for F6+

    International Nuclear Information System (INIS)

    Mitnik, D.M.; Pindzola, M.S.; Badnell, N.R.

    1999-01-01

    Total and partial recombination cross sections for F 6+ are calculated using close-coupling and distorted-wave theory. For total cross sections, close-coupling and distorted-wave results, which include interference between the radiative and dielectronic pathways, are found to be in good agreement with distorted-wave results based on a sum of independent processes. Total cross sections near zero energy are dominated by contributions from low-energy dielectronic recombination resonances. For partial cross sections, the close-coupling and distorted-wave theories predict strong interference for recombination into the final recombined ground state 1s 2 2s 21 S 0 of F 5+ , but only weak interference for recombination into the levels of the 1s 2 2s2p configuration. copyright 1999 The American Physical Society

  4. Automated Cross-Sectional Measurement Method of Intracranial Dural Venous Sinuses.

    Science.gov (United States)

    Lublinsky, S; Friedman, A; Kesler, A; Zur, D; Anconina, R; Shelef, I

    2016-03-01

    MRV is an important blood vessel imaging and diagnostic tool for the evaluation of stenosis, occlusions, or aneurysms. However, an accurate image-processing tool for vessel comparison is unavailable. The purpose of this study was to develop and test an automated technique for vessel cross-sectional analysis. An algorithm for vessel cross-sectional analysis was developed that included 7 main steps: 1) image registration, 2) masking, 3) segmentation, 4) skeletonization, 5) cross-sectional planes, 6) clustering, and 7) cross-sectional analysis. Phantom models were used to validate the technique. The method was also tested on a control subject and a patient with idiopathic intracranial hypertension (4 large sinuses tested: right and left transverse sinuses, superior sagittal sinus, and straight sinus). The cross-sectional area and shape measurements were evaluated before and after lumbar puncture in patients with idiopathic intracranial hypertension. The vessel-analysis algorithm had a high degree of stability with <3% of cross-sections manually corrected. All investigated principal cranial blood sinuses had a significant cross-sectional area increase after lumbar puncture (P ≤ .05). The average triangularity of the transverse sinuses was increased, and the mean circularity of the sinuses was decreased by 6% ± 12% after lumbar puncture. Comparison of phantom and real data showed that all computed errors were <1 voxel unit, which confirmed that the method provided a very accurate solution. In this article, we present a novel automated imaging method for cross-sectional vessels analysis. The method can provide an efficient quantitative detection of abnormalities in the dural sinuses. © 2016 by American Journal of Neuroradiology.

  5. From ZZ to ZH: How Low Can These Cross Sections Go or Everybody, Let's Cross Section Limbo

    International Nuclear Information System (INIS)

    Strauss, Emanuel Alexandre

    2009-01-01

    We report on two searches performed at the D0 detector at the Fermi National Laboratory. The first is a search for Z di-boson production with a theoretical cross section of 1.4 pb. The search was performed on 2.6 fb -1 of data and contributed to the first observation of ZZ production at a hadron collider. The second is a search for a low mass Standard Model Higgs in 4.2 fb -1 of data. The Higgs boson is produced in association with a Z boson where the Higgs decays hadronically and the Z decays to two leptons. The ZZ search was performed in both the di-electron and di-muon channels. For the ZH search, we will focus on the muonic decays where we expanded the traditional coverage by considering events in which one of the two muons fails the selection requirement, and is instead reconstructed as an isolated track. We consider Higgs masses between 100 and 150 GeV, with theoretical cross sections ranging from 0.17 to 0.042 pb, and set upper limits on the ZH production cross-section at 95% confidence level

  6. Quasiclassical trajectory study of the molecular beam kinetics of the deuterium atom--hydrogen halide exchange reactions

    International Nuclear Information System (INIS)

    Raff, L.M.; Suzukawa, H.H. Jr.; Thompson, D.L.

    1975-01-01

    Unadjusted quasiclassical trajectory computations have been carried out to simulate the molecular beam scattering of thermal D atom beams at 2800 degreeK crossed with beams of HCl and HI at 250 degreeK. Total reaction cross sections, energy partitioning distributions, and differential scattering cross sections have been computed for the exchange reactions D+HCl → DCl+H and D+HI → DI+H while total reaction cross sections are reported for the corresponding abstractions, i.e., D+HCl → HD+Cl and D+HI → HD+I. For the exchange reactions, the computed reaction cross sections are within the range estimated from the crossed beam experiments. The calculated average energy partitioned into relative translational motion of products is in near quantitative agreement with the beam results, and the predicted differential scattering cross sections appear to be in qualitative accord with the beam experiments. The over-all agreement between theory and experiment indicates that previously computed values for the thermal rate coefficients for the exchange reactions are of the right order and that a systematic error exists in the interpretation of photolysis data in the hydrogen--hydrogen halide systems

  7. Resonance parameters for measured keV neutron capture cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Musgrove, A.R. de L

    1969-05-01

    All available neutron capture cross sections in the keV region ({approx} to 100 keV) have been fitted with resonance parameters. Capture cross sections for nuclides with reasonably well known average s-wave parameters, but no measured cross section, have been calculated and tabulated using p-and d- wave strength functions interpolated between fitted values. Several of these nuclides are of interest in the theory of slow nucleosynthesis of heavy elements in stars, and the product of cosmic abundance (due to the s-process) and capture cross section at 30 keV has been plotted versus mass number. (author)

  8. Measurement of 76Se and 78Se (γ, n) cross sections

    International Nuclear Information System (INIS)

    Kitatani, Fumito; Harada, Hideo; Goko, Shinji; Utsunomiya, Hiroaki; Akimune, Hidetoshi; Toyokawa, Hiroyuki; Yamada, Kawakatsu

    2011-01-01

    The (γ, n) cross sections of Se isotopes ( 76 Se, 78 Se) were measured to supply fundamental data for estimating the inverse reaction cross section, i.e., the 79 Se(n, γ) 80 Se cross section. The enriched samples and a reference 197 Au sample were irradiated with laser-Compton scattering (LCS) γ-rays. The excitation function of each (γ, n) cross section was determined for the energy range from each near neutron separation energy to the threshold energy of (γ, 2n) reaction. The energy point corresponding to each cross section was deduced using the accurately determined energy distribution of LCS γ-rays. Systematic (γ, n) cross sections for Se isotopes including 80 Se were compared with those calculated by using a statistical model calculation code TALYS. (author)

  9. Probing two-photon exchange with OLYMPUS

    International Nuclear Information System (INIS)

    Kohl, M.

    2014-01-01

    Two-photon exchange is believed to be responsible for the discrepancies in the proton electric to magnetic form factor ratio found with the Rosenbluth and polarization transfer methods. If this explanation is correct, one expects significant differences in the lepton-proton cross sections between positrons and electrons. The OLYMPUS experiment at DESY in Hamburg, Germany was designed to measure the ratio of unpolarized positron-proton and electron-proton elastic scattering cross sections over a wide kinematic range with high precision, in order to quantify the effect of two-photon exchange. The experiment used intense beams of electrons and positrons stored in the DORIS ring at 2.0 GeV interacting with an internal windowless hydrogen gas target. The current status of OLYMPUS will be discussed. (authors)

  10. CrossRef Large numbers of cold positronium atoms created in laser-selected Rydberg states using resonant charge exchange

    CERN Document Server

    McConnell, R; Kolthammer, WS; Richerme, P; Müllers, A; Walz, J; Grzonka, D; Zielinski, M; Fitzakerley, D; George, MC; Hessels, EA; Storry, CH; Weel, M

    2016-01-01

    Lasers are used to control the production of highly excited positronium atoms (Ps*). The laser light excites Cs atoms to Rydberg states that have a large cross section for resonant charge-exchange collisions with cold trapped positrons. For each trial with 30 million trapped positrons, more than 700 000 of the created Ps* have trajectories near the axis of the apparatus, and are detected using Stark ionization. This number of Ps* is 500 times higher than realized in an earlier proof-of-principle demonstration (2004 Phys. Lett. B 597 257). A second charge exchange of these near-axis Ps* with trapped antiprotons could be used to produce cold antihydrogen, and this antihydrogen production is expected to be increased by a similar factor.

  11. Odderon and photon exchange in electroproduction of pseudoscalar mesons

    CERN Document Server

    Berger, Edgar R.; Dosch, Hans Gunter; Kilian, W.; Nachtmann, O.; Rueter, M.

    1999-01-01

    We investigate the reaction $e p \\to e PS X$ where PS denotes a pseudoscalar meson $\\pi^0, \\eta, \\eta'$, or $\\eta_c$ and X either a proton or resonance or continuum states into which the proton can go by diffractive excitation. At high energies photon and odderon exchange contribute to the reaction. The photon exchange contribution is evaluated exactly using data for the total virtual photon-proton absorption cross section. The odderon exchange contribution is calculated in nonperturbative QCD, using functional integral techniques and the model of the stochastic vacuum. For the proton we assume a quark-diquark structure as suggested by the small odderon amplitude in $pp$ and $p \\bar{p}$ forward scattering. We show that odderon exchange leads to a much larger inelastic than elastic PS production cross section. Observation of our reaction at HERA would establish the soft odderon as an exchange object on an equal footing with the soft pomeron and would give us valuable insight into both the nucleon structure and...

  12. Can cross sections be accurately known for priori?

    International Nuclear Information System (INIS)

    Pigni, M.T.; Dietrich, F.S.; Herman, M.; Oblozinsky, P.

    2008-01-01

    Distinct maxima and minima in the neutron total cross section uncertainties were observed in our large scale covariance calculations using a spherical optical potential. In this contribution we investigate the physical origin of this oscillating structure. Specifically, we analyze the case of neutron reactions on 56 Fe, for which total cross section uncertainties are characterized by the presence of five distinct minima at 0.1, 1.1, 5, 25, and 70 MeV. To investigate their origin, we calculated total cross sections by perturbing the real volume depth V v by its expected uncertainty ±ΔV v . Inspecting the effect of this perturbation on the partial wave cross sections we found that the first minimum (at 0.1 MeV) is exclusively due to the contribution of the s-wave. On the other hand, the same analysis at 1.1 MeV showed that the minimum is the result of the interplay between s-, p-, and d-waves; namely the change in the s-wave happens to be counterbalanced by changes in the p- and d-waves. Similar considerations can be extended for the third minimum, although it can be also explained in terms of the Ramsauer effect as well as the other ones (at 25 and 70 MeV). We discuss the potential importance of these minima for practical applications as well as the implications of this work for the uncertainties in total and absorption cross sections

  13. Models for Pooled Time-Series Cross-Section Data

    Directory of Open Access Journals (Sweden)

    Lawrence E Raffalovich

    2015-07-01

    Full Text Available Several models are available for the analysis of pooled time-series cross-section (TSCS data, defined as “repeated observations on fixed units” (Beck and Katz 1995. In this paper, we run the following models: (1 a completely pooled model, (2 fixed effects models, and (3 multi-level/hierarchical linear models. To illustrate these models, we use a Generalized Least Squares (GLS estimator with cross-section weights and panel-corrected standard errors (with EViews 8 on the cross-national homicide trends data of forty countries from 1950 to 2005, which we source from published research (Messner et al. 2011. We describe and discuss the similarities and differences between the models, and what information each can contribute to help answer substantive research questions. We conclude with a discussion of how the models we present may help to mitigate validity threats inherent in pooled time-series cross-section data analysis.

  14. Homogenized group cross sections by Monte Carlo

    International Nuclear Information System (INIS)

    Van Der Marck, S. C.; Kuijper, J. C.; Oppe, J.

    2006-01-01

    Homogenized group cross sections play a large role in making reactor calculations efficient. Because of this significance, many codes exist that can calculate these cross sections based on certain assumptions. However, the application to the High Flux Reactor (HFR) in Petten, the Netherlands, the limitations of such codes imply that the core calculations would become less accurate when using homogenized group cross sections (HGCS). Therefore we developed a method to calculate HGCS based on a Monte Carlo program, for which we chose MCNP. The implementation involves an addition to MCNP, and a set of small executables to perform suitable averaging after the MCNP run(s) have completed. Here we briefly describe the details of the method, and we report on two tests we performed to show the accuracy of the method and its implementation. By now, this method is routinely used in preparation of the cycle to cycle core calculations for HFR. (authors)

  15. Double-differential heavy-ion production cross sections

    International Nuclear Information System (INIS)

    Miller, T. M.; Townsend, L. W.

    2004-01-01

    Current computational tools used for space or accelerator shielding studies transport energetic heavy ions either using a one-dimensional straight-ahead approximation or by dissociating the nuclei into protons and neutrons and then performing neutron and proton transport using Monte Carlo techniques. Although the heavy secondary particles generally travel close to the beam direction, a proper treatment of the light ions produced in these reactions requires that double-differential cross sections should be utilised. Unfortunately, no fundamental nuclear model capable of serving as an event generator to provide these cross sections for all ions and energies of interest exists currently. Herein, we present a model for producing double-differential heavy-ion production cross sections that uses heavy-ion fragmentation yields produced by the NUCFRG2 fragmentation code coupled with a model of energy degradation in nucleus-nucleus collisions and systematics of momentum distributions to provide energy and angular dependences of the heavy-ion production. (authors)

  16. Prospects for Precision Neutrino Cross Section Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Deborah A. [Fermilab

    2016-01-28

    The need for precision cross section measurements is more urgent now than ever before, given the central role neutrino oscillation measurements play in the field of particle physics. The definition of precision is something worth considering, however. In order to build the best model for an oscillation experiment, cross section measurements should span a broad range of energies, neutrino interaction channels, and target nuclei. Precision might better be defined not in the final uncertainty associated with any one measurement but rather with the breadth of measurements that are available to constrain models. Current experience shows that models are better constrained by 10 measurements across different processes and energies with 10% uncertainties than by one measurement of one process on one nucleus with a 1% uncertainty. This article describes the current status of and future prospects for the field of precision cross section measurements considering the metric of how many processes, energies, and nuclei have been studied.

  17. Measurements of neutron cross sections of radioactive waste nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Katoh, Toshio [Gifu College of Medical Technology, Seki, Gifu (Japan); Harada, Hideo; Nakamura, Shoji; Tanase, Masakazu; Hatsukawa, Yuichi

    1998-01-01

    Accurate nuclear reaction cross sections of radioactive fission products and transuranic elements are required for research on nuclear transmutation methods in nuclear waste management. Important fission products in the nuclear waste management are {sup 137}Cs, {sup 135}Cs, {sup 90}Sr, {sup 99}Tc and {sup 129}I because of their large fission yields and long half-lives. The present authors have measured the neutron capture cross sections and resonance integrals of {sup 137}Cs, {sup 90}Sr and {sup 99}Tc. The purpose of this study is to measure the neutron capture cross sections and resonance integrals of nuclides, {sup 129}I and {sup 135}Cs accurately. Preliminary experiments were performed by using Rikkyo University Reactor and JRR-3 reactor at Japan Atomic Energy Research Institute (JAERI). Then, it was decided to measure the cross section and resonance integral of {sup 135}Cs by using the JRR-3 Reactor because this measurement required a high flux reactor. On the other hand, those of {sup 129}I were measured at the Rikkyo Reactor because the product nuclides, {sup 130}I and {sup 130m}I, have short half-lives and this reactor is suitable for the study of short lived nuclide. In this report, the measurements of the cross section and resonance integral of {sup 135}Cs are described. To obtain reliable values of the cross section and resonance integral of {sup 135}Cs(n, {gamma}){sup 136}Cs reaction, a quadrupole mass spectrometer was used for the mass analysis of nuclide in the sample. A progress report on the cross section of {sup 134}Cs, a neighbour of {sup 135}Cs, is included in this report. A report on {sup 129}I will be presented in the Report on the Joint-Use of Rikkyo University Reactor. (author)

  18. Neutron cross sections for fusion

    International Nuclear Information System (INIS)

    Haight, R.C.

    1979-10-01

    First generation fusion reactors will most likely be based on the 3 H(d,n) 4 He reaction, which produces 14-MeV neutrons. In these reactors, both the number of neutrons and the average neutron energy will be significantly higher than for fission reactors of the same power. Accurate neutron cross section data are therefore of great importance. They are needed in present conceptual designs to calculate neutron transport, energy deposition, nuclear transmutation including tritium breeding and activation, and radiation damage. They are also needed for the interpretation of radiation damage experiments, some of which use neutrons up to 40 MeV. In addition, certain diagnostic measurements of plasma experiments require nuclear cross sections. The quality of currently available data for these applications will be reviewed and current experimental programs will be outlined. The utility of nuclear models to provide these data also will be discussed. 65 references

  19. Development of automatic cross section compilation system for MCNP

    International Nuclear Information System (INIS)

    Maekawa, Fujio; Sakurai, Kiyoshi

    1999-01-01

    A development of a code system to automatically convert cross-sections for MCNP is in progress. The NJOY code is, in general, used to convert the data compiled in the ENDF format (Evaluated Nuclear Data Files by BNL) into the cross-section libraries required by various reactor physics codes. While the cross-section library: FSXLIB-J3R2 was already converted from the JENDL-3.2 version of Japanese Evaluated Nuclear Data Library for a continuous energy Monte Carlo code MCNP, the library keeps only the cross-sections at room temperature (300 K). According to the users requirements which want to have cross-sections at higher temperature, say 600 K or 900 K, a code system named 'autonj' is under development to provide a set of cross-section library of arbitrary temperature for the MCNP code. This system can accept any of data formats adopted JENDL that may not be treated by NJOY code. The input preparation that is repeatedly required at every nuclide on NJOY execution is greatly reduced by permitting the conversion process of as many nuclides as the user wants in one execution. A few MCNP runs were achieved for verification purpose by using two libraries FSXLIB-J3R2 and the output of autonj'. The almost identical MCNP results within the statistical errors show the 'autonj' output library is correct. In FY 1998, the system will be completed, and in FY 1999, the user's manual will be published. (K. Tsuchihashi)

  20. EDDIX--a database of ionisation double differential cross sections.

    Science.gov (United States)

    MacGibbon, J H; Emerson, S; Liamsuwan, T; Nikjoo, H

    2011-02-01

    The use of Monte Carlo track structure is a choice method in biophysical modelling and calculations. To precisely model 3D and 4D tracks, the cross section for the ionisation by an incoming ion, double differential in the outgoing electron energy and angle, is required. However, the double differential cross section cannot be theoretically modelled over the full range of parameters. To address this issue, a database of all available experimental data has been constructed. Currently, the database of Experimental Double Differential Ionisation Cross sections (EDDIX) contains over 1200 digitalised experimentally measured datasets from the 1960s to present date, covering all available ion species (hydrogen to uranium) and all available target species. Double differential cross sections are also presented with the aid of an eight parameter functions fitted to the cross sections. The parameters include projectile species and charge, target nuclear charge and atomic mass, projectile atomic mass and energy, electron energy and deflection angle. It is planned to freely distribute EDDIX and make it available to the radiation research community for use in the analytical and numerical modelling of track structure.

  1. Handbook of LHC Higgs Cross Sections: 3. Higgs Properties Report of the LHC Higgs Cross Section Working Group

    CERN Document Server

    Heinemeyer, S; Passarino, G; Tanaka, R; Andersen, J R; Artoisenet, P; Bagnaschi, E A; Banfi, A; Becher, T; Bernlochner, F U; Bolognesi, S; Bolzoni, P; Boughezal, R; Buarque, D; Campbell, J; Caola, F; Carena, M; Cascioli, F; Chanon, N; Cheng, T; Choi, S Y; David, A; de Aquino, P; Degrassi, G; Del Re, D; Denner, A; van Deurzen, H; Diglio, S; Di Micco, B; Di Nardo, R; Dittmaier, S; Dührssen, M; Ellis, R K; Ferrera, G; Fidanza, N; Flechl, M; de Florian, D; Forte, S; Frederix, R; Frixione, S; Gangal, S; Gao, Y; Garzelli, M V; Gillberg, D; Govoni, P; Grazzini, M; Greiner, N; Griffiths, J; Gritsan, A V; Grojean, C; Hall, D C; Hays, C; Harlander, R; Hernandez-Pinto, R; Höche, S; Huston, J; Jubb, T; Kadastik, M; Kallweit, S; Kardos, A; Kashif, L; Kauer, N; Kim, H; Klees, R; Krämer, M; Krauss, F; Laureys, A; Laurila, S; Lehti, S; Li, Q; Liebler, S; Liu, X; Logan, E; Luisoni, G; Malberti, M; Maltoni, F; Mawatari, K; Maierhoefer, F; Mantler, H; Martin, S; Mastrolia, P; Mattelaer, O; Mazzitelli, J; Mellado, B; Melnikov, K; Meridiani, P; Miller, D J; Mirabella, E; Moch, S O; Monni, P; Moretti, N; Mück, A; Mühlleitner, M; Musella, P; Nason, P; Neu, C; Neubert, M; Oleari, C; Olsen, J; Ossola, G; Peraro, T; Peters, K; Petriello, F; Piacquadio, G; Potter, C T; Pozzorini, S; Prokofiev, K; Puljak, I; Rauch, M; Rebuzzi, D; Reina, L; Rietkerk, R; Rizzi, A; Rotstein-Habarnau, Y; Salam, G P; Sborlini, G; Schissler, F; Schönherr, M; Schulze, M; Schumacher, M; Siegert, F; Slavich, P; Smillie, J M; Stål, O; von Soden-Fraunhofen, J F; Spira, M; Stewart, I W; Tackmann, F J; Taylor, P T E; Tommasini, D; Thompson, J; Thorne, R S; Torrielli, P; Tramontano, F; Tran, N V; Trócsányi, Z; Ubiali, M; Vazquez Acosta, M; Vickey, T; Vicini, A; Waalewijn, W J; Wackeroth, D; Wagner, C; Walsh, J R; Wang, J; Weiglein, G; Whitbeck, A; Williams, C; Yu, J; Zanderighi, G; Zanetti, M; Zaro, M; Zerwas, P M; Zhang, C; Zirke, T J E; Zuberi, S

    2013-01-01

    This Report summarizes the results of the activities in 2012 and the first half of 2013 of the LHC Higgs Cross Section Working Group. The main goal of the working group was to present the state of the art of Higgs Physics at the LHC, integrating all new results that have appeared in the last few years. This report follows the first working group report Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables (CERN-2011-002) and the second working group report Handbook of LHC Higgs Cross Sections: 2. Differential Distributions (CERN-2012-002). After the discovery of a Higgs boson at the LHC in mid-2012 this report focuses on refined prediction of Standard Model (SM) Higgs phenomenology around the experimentally observed value of 125-126 GeV, refined predictions for heavy SM-like Higgs bosons as well as predictions in the Minimal Supersymmetric Standard Model and first steps to go beyond these models. The other main focus is on the extraction of the characteristics and properties of the newly discovered p...

  2. Highlights of top quark cross-section measurements at ATLAS

    Directory of Open Access Journals (Sweden)

    Berta Peter

    2017-01-01

    Full Text Available The highlights of the measurements of top quark production in proton-proton collisions at the Large Hadron Collider with the ATLAS detector are presented. The inclusive measurements of the top-pair production cross section have reached high precision and are compared to the best available theoretical calculations. The differential cross section measurements, including results using boosted top quarks, probe our understanding of top-pair production in the TeV regime. The results are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers. Measurements of the single top quark production cross section are presented in the t-channel and s-channel, and with associated production with a W boson. For the t-channel production, results on the ratio between top quark and antitop quark production cross sections and differential measurements are also included.

  3. Handbook of LHC Higgs Cross Sections: 2. Differential Distributions

    CERN Document Server

    Dittmaier, S; Passarino, G; Tanaka, R; Alekhin, S; Alwall, J; Bagnaschi, E A; Banfi, A; Blumlein, J; Bolognesi, S; Chanon, N; Cheng, T; Cieri, L; Cooper-Sarkar, A M; Cutajar, M; Dawson, S; Davies, G; De Filippis, N; Degrassi, G; Denner, A; D'Enterria, D; Diglio, S; Di Micco, B; Di Nardo, R; Ellis, R K; Farilla, A; Farrington, S; Felcini, M; Ferrera, G; Flechl, M; de Florian, D; Forte, S; Ganjour, S; Garzelli, M V; Gascon-Shotkin, S; Glazov, S; Goria, S; Grazzini, M; Guillet, J -Ph; Hackstein, C; Hamilton, K; Harlander, R; Hauru, M; Heinemeyer, S; Hoche, S; Huston, J; Jackson, C; Jimenez-Delgado, P; Jorgensen, M D; Kado, M; Kallweit, S; Kardos, A; Kauer, N; Kim, H; Kovac, M; Kramer, M; Krauss, F; Kuo, C -M; Lehti, S; Li, Q; Lorenzo, N; Maltoni, F; Mellado, B; Moch, S O; Muck, A; Muhlleitner, M; Nadolsky, P; Nason, P; Neu, C; Nikitenko, A; Oleari, C; Olsen, J; Palmer, S; Paganis, S; Papadopoulos, C G; Petersen, T C; Petriello, F; Petrucci, F; Piacquadio, G; Pilon, E; Potter, C T; Price, J; Puljak, I; Quayle, W; Radescu, V; Rebuzzi, D; Reina, L; Rojo, J; Rosco, D; Salam, G P; Sapronov, A; Schaarschmidt, J; Schonherr, M; Schumacher, M; Siegert, F; Slavich, P; Spira, M; Stewart, I W; Stirling, W J; Stockli, F; Sturm, C; Tackmann, F J; Thorne, R S; Tommasini, D; Torrielli, P; Tramontano, F; Trocsanyi, Z; Ubiali, M; Uccirati, S; Acosta, M Vazquez; Vickey, T; Vicini, A; Waalewijn, W J; Wackeroth, D; Warsinsky, M; Weber, M; Wiesemann, M; Weiglein, G; Yu, J; Zanderighi, G

    2012-01-01

    This Report summarises the results of the second year's activities of the LHC Higgs Cross Section Working Group. The main goal of the working group was to present the state of the art of Higgs Physics at the LHC, integrating all new results that have appeared in the last few years. The first working group report Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables (CERN-2011-002) focuses on predictions (central values and errors) for total Higgs production cross sections and Higgs branching ratios in the Standard Model and its minimal supersymmetric extension, covering also related issues such as Monte Carlo generators, parton distribution functions, and pseudo-observables. This second Report represents the next natural step towards realistic predictions upon providing results on cross sections with benchmark cuts, differential distributions, details of specific decay channels, and further recent developments.

  4. Cross-lined PEEK proton exchange membranes for fuel cell - Conference Poster

    CSIR Research Space (South Africa)

    Luo, H

    2009-07-01

    Full Text Available The low-cost cross-linked Polyetheretherketone (PEEK) proton exchange membranes were prepared via the simple route. The membranes exhibited similar electrochemical properties as compared with commercial Nafion. The membranes were highly proton...

  5. Plutonium-239 fission cross-section between 1 and 100 keV - International Evaluation Co-operation Volume 5

    International Nuclear Information System (INIS)

    Fort, E.; Salvatores, M.; Derrien, H.; Lagrange, Ch.; Kawai, M.; Nakajima, J.; Takano, H.; Weston, L.W.; Young, P.G.; Wagemans, C.

    1994-01-01

    A Working Party on International Evaluation Co-operation was established under the sponsorship of the OECD/NEA Nuclear Science Committee (NSC) to promote the exchange of information on nuclear data evaluations, validation, and related topics. Its aim is also to provide a framework for co-operative activities between members of the major nuclear data evaluation projects. This includes the possible exchange of scientists in order to encourage co-operation. Requirements for experimental data resulting from this activity are compiled. The Working Party determines common criteria for evaluated nuclear data files with a view to assessing and improving the quality and completeness of evaluated data. The Parties to the project are: ENDF (United States), JEFF/EFF (NEA Data Bank Member countries), and JENDL (Japan). Co-operation with evaluation projects of non-OECD countries are organised through the Nuclear Data Section of the International Atomic Energy Agency (IAEA). The following report was issued by a Subgroup investigating the fission cross-section of Plutonium-239 in the energy range 1 to 100 keV. This cross section is of particular importance for fast reactor applications, such as k eff , sodium void reactivity coefficient and control rod worth. An analysis of recent experimental data by L. Weston et al. give significantly lower cross-section values that the simultaneous evaluation performed by W. Poenitz for the ENDF/B-VI library. The objective of the subgroup was to resolve this discrepancy. One experimental program and one evaluation one have been agreed upon: The experimental program which essentially aims at normalisation checking has been performed in Geel and Oak Ridge. It supports an upward re-normalisation by ∼3.1%. The evaluation program has not been completed and even, as a consequence of the experimental results, loses a part of its justification. But some acquired results are important and can be used for future 239 Pu evaluations. The JEFF-2

  6. Fe L-shell Excitation Cross Section Measurements on EBIT-I

    Science.gov (United States)

    Chen, Hui; Beiersdorfer, P.; Brown, G.; Boyce, K.; Kelley, R.; Kilbourne, C.; Porter, F.; Gu, M. F.; Kahn, S.

    2006-09-01

    We report the measurement of electron impact excitation cross sections for the strong iron L-shell 3-2 lines of Fe XVII to Fe XXIV at the LLNL EBIT-I electron beam ion trap using a crystal spectrometer and NASA-Goddard Space Flight Center's 6x6 pixel array microcalorimeter. The cross sections were determined by direct normalization to the well-established cross sections for radiative electron capture. Our results include the excitation cross section for over 50 lines at multiple electron energies. Although we have found that for 3C line in Fe XVII the measured cross sections differ significantly from theory, in most cases the measurements and theory agree within 20%. This work was performed under the auspices of the U.S. DOE by LLNL under contract No. W-7405-Eng-48 and supported by NASA APRA grants to LLNL, GSFC, and Stanford University.

  7. Neutron-induced capture cross sections via the surrogate reaction method

    International Nuclear Information System (INIS)

    Boutoux, G.; Jurado, B.; Aiche, M.; Barreau, G.; Capellan, N.; Companis, I.; Czajkowski, S.; Dassie, D.; Haas, B.; Mathieu, L.; Meot, V.; Bail, A.; Bauge, E.; Daugas, J. M.; Faul, T.; Gaudefroy, L.; Morel, P.; Pillet, N.; Roig, O.; Romain, P.; Taieb, J.; Theroine, C.; Burke, J.T.; Companis, I.; Derkx, X.; Gunsing, F.; Matea, I.; Tassan-Got, L.; Porquet, M.G.; Serot, O.

    2011-01-01

    The surrogate reaction method is an indirect way of determining cross sections for nuclear reactions that proceed through a compound nucleus. This technique enables neutron-induced cross sections to be extracted for nuclear reactions on short-lived unstable nuclei that otherwise can not be measured. This technique has been successfully applied to determine the neutron-induced fission cross sections of several short-lived nuclei. In this work, we investigate whether this powerful technique can also be used to determine of neutron-induced capture cross sections. For this purpose we use the surrogate reaction 174 Yb( 3 He, pγ) 176 Lu to infer the well known 175 Lu(n, γ) cross section and compare the results with the directly measured neutron-induced data. This surrogate experiment has been performed in March 2010. The experimental technique used and the first preliminary results will be presented. (authors)

  8. Terahertz radar cross section measurements

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-01-01

    We perform angle- and frequency-resolved radar cross section (RCS) measurements on objects at terahertz frequencies. Our RCS measurements are performed on a scale model aircraft of size 5-10 cm in polar and azimuthal configurations, and correspond closely to RCS measurements with conventional radar...

  9. Second order effects in adjustment processes of cross sections

    International Nuclear Information System (INIS)

    Silva, F.C. da; D'Angelo, A.; Gandini, A.; Rado, V.

    1982-01-01

    An iterative processe, that take in account the non linear effects of some integral quantities in relation to cross sections, is used to execute an adjustment of cross sections of some elements that constitute the fast reactors shielding. (E.G.) [pt

  10. Adjustement of multigroup cross sections using fast reactor integral data

    International Nuclear Information System (INIS)

    Renke, C.A.C.

    1982-01-01

    A methodology for the adjustment of multigroup cross section is presented, structured with aiming to compatibility the limitated number of measured values of integral parameters known and disponible, and the great number of cross sections to be adjusted the group of cross section used is that obtained from the Carnaval II calculation system, understanding as formular the sets of calculation methods and data bases. The adjustment is realized, using the INCOAJ computer code, developed in function of one statistical formulation, structural from the bayer considerations, taking in account the measurement processes of cross section and integral parameters defined on statistical bases. (E.G.) [pt

  11. Defining SNAP by cross-sectional and longitudinal definitions of neurodegeneration

    OpenAIRE

    Wisse, L.E.M.; Das, S.R.; Davatzikos, C.; Dickerson, B.C.; Xie, S.X.; Yushkevich, P.A.; Wolk, D.A.

    2018-01-01

    Introduction: Suspected non-Alzheimer's pathophysiology (SNAP) is a biomarker driven designation that represents a heterogeneous group in terms of etiology and prognosis. SNAP has only been identified by cross-sectional neurodegeneration measures, whereas longitudinal measures might better reflect “active” neurodegeneration and might be more tightly linked to prognosis. We compare neurodegeneration defined by cross-sectional ‘hippocampal volume’ only (SNAP/L−) versus both cross-sectional and ...

  12. Charge exchange in collisions of beryllium with its ion.

    Science.gov (United States)

    Zhang, Peng; Dalgarno, Alexander; Côté, Robin; Bodo, Enrico

    2011-11-14

    Close-coupling calculations of the resonance and near resonance charge exchange in ion-atom collisions of Be at low and intermediate energies are presented. Accurate ab initio calculations are carried out of the Born-Oppenheimer potentials and the non-adiabatic couplings that are due to the finite nuclear masses and drive the near resonance charge exchange. We show that the near resonance charge exchange cross section follows Wigner's threshold law of inelastic processes for energies below 10(-8) eV and that the zero temperature rate constant for it is 4.5 × 10(-10) cm(3) s(-1). At collision energies much larger than the isotope shift of the ionization potentials of the atoms, we show that the near resonance charge exchange process is equivalent to the resonance charge exchange with cross sections having a logarithmic dependence. We also investigate the perturbation to the charge exchange process due to the non-adiabatic interaction to an electronic excited state. We show that the influence is negligible at low temperatures and still small at intermediate energies despite the presence of resonances.

  13. Cross sections and equilibrium fractions of deuterium ions and atoms in metal vapors. Progress report, June 1, 1978-May 31, 1979

    International Nuclear Information System (INIS)

    Morgan, T.J.

    1979-01-01

    The purpose of this program is to measure cross sections and equilibrium fractions of deuterium ions and atoms in metal vapors. In particular, in connection with double charge exchange D - ion sources, there is concern with D - formation in alkaline-earth vapor targets. Also, in connection with possible metal vapor contamination in the system, there is concern with cross sections for high energy D + , D 0 and D - collisions with these metal vapors. Results from this research will fill in a gap in knowledge of single and double charge transfer and multiple collision processes in alkaline-earth targets and provide a better understanding of D - formation mechanisms. A list of publications is included. 6 references

  14. Neutrino-carbon cross section in QRPA models

    International Nuclear Information System (INIS)

    Samana, Arturo R.; Krmpotic, Francisco; Bertulani, Carlos A.; Paar, Nils

    2009-01-01

    Full text follows. The ν/ν-bar - 12 C cross sections are calculated in the projected quasiparticle random phase approximation (PQRPA) [1,2] and the relativistic quasiparticle random phase approximation (RQRPA) [3,4]. We compare these cross section as a function of the incident neutrino energy and the number of shells used in the nuclear structure calculation. Additional comparison with other RPA models are performed. A guide to find an upper limit of the incident neutrino energy as a function of the number of shell is implemented. Important consequences on the extrapolation of the cross section to higher neutrino energies is discussed. The formalism obtained in Ref. [1] for the neutrino interaction is extended for antineutrino scattering. This formalism includes the effect of the violation of the Conserved Vector Current by the Coulomb field. It is furthermore simplified by classifying the nuclear matrix elements in natural and unnatural parities. The distribution of cross sections averaged with the Michel spectrum as well as with other estimated fluxes for future experiments are compared for ν e and ν-bar e . Some astrophysical implications are addressed. References [1] F. Krmpotic, A. Mariano and A. Samana, Phys.Lett. B541, 298 (2002). [2] F. Krmpotic, A. Mariano and A. Samana, Phys. Rev. C 71, 044319 (2005). [3] N. Paar, T. Niksic, D. Vretenar, and P. Ring, Phys. Rev. C 69, 054303 (2004). [4] N. Paar, D. Vretenar, T. Marketin and P. Ring, Phys. Rev. C 77, 024608 (2008)

  15. Update to the R33 cross section file format

    International Nuclear Information System (INIS)

    Vickridge, I.C.

    2003-01-01

    In September 1991, in response to the workshop on cross sections for Ion Beam Analysis (IBA) held in Namur (July 1991, Nuclear Instruments and Methods B66(1992)), a simple ascii format was proposed to facilitate transfer and collation of nuclear reaction cross section data for Ion Beam Analysis (IBA) and especially for Nuclear Reaction Analysis (NRA). Although intended only as a discussion document, the ascii format - referred to as the R33 (Report 33) format - has become a de facto standard. In the decade since this first proposal there have been spectacular advances in computing power and in software usability, however the cross-platform compatibility of the ascii character set has ensured that the need for an ascii format remains. Nuclear reaction cross section data for Nuclear Reaction analysis has been collected and archived on internet web sites over the last decade. This data has largely been entered in the R33 format, although there is a series of elastic cross sections that are expressed as the ratio to the corresponding Rutherford cross sections that have been entered in a format referred to as RTR (ratio to Rutherford). During this time the R33 format has been modified and added to - firstly to take into account angular distributions, which were not catered for in the first proposal, and more recently to cater for elastic cross sections expressed as the ratio-to- Rutherford, which it is useful to have for some elastic scattering programs. It is thus timely to formally update the R33 format. There also exists the large nuclear cross section data collections of the Nuclear Data Network - of which the core centres are the OECD NEA Nuclear Data Bank, the IAEA Nuclear Data Section, the Brookhaven National Laboratory National Nuclear Data Centre and CJD IPPE Obninsk, Russia. The R33 format is now proposed to become a legal computational format for the NDN. It is thus also necessary to provide an updated formal definition of the R33 format in order to provide

  16. Radar cross sections for mesospheric echoes at Jicamarca

    Directory of Open Access Journals (Sweden)

    G. A. Lehmacher

    2009-07-01

    Full Text Available Radar cross sections (RCS of mesospheric layers at 50 MHz observed at Jicamarca, Peru, range from 10−18 to 10−16 m−1, three orders of magnitudes smaller than cross sections reported for polar mesospheric winter echoes during solar proton events and six orders of magnitude smaller than polar mesospheric summer echoes. Large RCS are found in thick layers around 70 km that also show wide radar spectra, which is interpreted as turbulent broadening. For typical atmospheric and ionospheric conditions, volume scattering RCS for stationary, homogeneous, isotropic turbulence at 3 m are also in the range 10−18 to 10−16 m−1, in reasonable agreement with measurements. Moreover, theory predicts maximum cross sections around 70 km, also in agreement with observations. Theoretical values are still a matter of order-of-magnitude estimation, since the Bragg scale of 3 m is near or inside the viscous subrange, where the form of the turbulence spectrum is not well known. In addition, steep electron density gradients can increase cross-sections significantly. For thin layers with large RCS and narrow spectra, isotropic turbulence theory fails and scattering or reflection from anisotropic irregularities may gain relevance.

  17. Partial wave analysis for folded differential cross sections

    Science.gov (United States)

    Machacek, J. R.; McEachran, R. P.

    2018-03-01

    The value of modified effective range theory (MERT) and the connection between differential cross sections and phase shifts in low-energy electron scattering has long been recognized. Recent experimental techniques involving magnetically confined beams have introduced the concept of folded differential cross sections (FDCS) where the forward (θ ≤ π/2) and backward scattered (θ ≥ π/2) projectiles are unresolved, that is the value measured at the angle θ is the sum of the signal for particles scattered into the angles θ and π - θ. We have developed an alternative approach to MERT in order to analyse low-energy folded differential cross sections for positrons and electrons. This results in a simplified expression for the FDCS when it is expressed in terms of partial waves and thereby enables one to extract the first few phase shifts from a fit to an experimental FDCS at low energies. Thus, this method predicts forward and backward angle scattering (0 to π) using only experimental FDCS data and can be used to determine the total elastic cross section solely from experimental results at low-energy, which are limited in angular range.

  18. Nuclear Data Processing for Generation of Stainless Steel Cross-Sections Data

    International Nuclear Information System (INIS)

    Suwoto; Zuhair

    2007-01-01

    Stainless steel has been used as important material in nuclear reactor and also in non nuclear industries. Nuclear data processing for generation of composite mixture cross-sections from several nuclides have been made. Provided evaluated nuclear data file (ENDF) such as ENDF/B- VI.8, JEFF-3.1 and JENDL-3.3 files were employed. Raw nuclear data cross-sections on file ENDF should be prepared and processed before it used in calculation. Sequence of nuclear data processing for generation of mixture cross-sections data from several nuclides is started from LINEAR, RECENT, SIGMA1 and MIXER codes taken from PREPR02000 utility code. Nuclear data processing is started from linearization of nuclear cross-sections data by using LINEAR code and counting background contribution of resonance parameter (MF2) with RECENT code (0 K) at energy ranges from 10 -5 to 10 7 eV. Afterward, the neutron cross-sections data should be processed and broadened to desire temperature (300 K) by using SIGMA1 code. Consistency of each cross-sections which used in nuclear data processing is checked and verified using FIXUP code. The next step is to define the composite mixture density (gr/cm 3 ) of stainless steel SUS-310 and weight fraction of each nuclide composition prior used it in MIXER code. All of the stainless steel SUS-310 cross sections are condensed to 650 energy groups structure (TART-energy structure) by using GROUPIE code to evaluate, analysis and review it more easily. The total, elastic scattering, non-elastic scattering and capture cross- sections of stainless steel SUS-310 have been made of ENDF/B-VI.8, JEFF-3.1 and JENDL-3.3 files. The stainless steel cross-sections made of ENDF/B- VI.8 file was taken as reference during validation process. The validation result of total cross-sections for stainless steel SUS-310 is clearly observed that the differences of total cross-sections error in nuclear data processing is relatively low than 0.01%. (author)

  19. Study of K/sup -/p. -->. anti K*(890)n at 13GeV. [Differential cross sections, density matrix elements

    Energy Technology Data Exchange (ETDEWEB)

    Brandenburg, G W; Dunwoodie, W M; Lasinski, T A; Leith, D W.G.S.; Williams, S H [Stanford Linear Accelerator Center, Calif. (USA); Carnegie, R K [Carleton Univ., Ottawa, Ontario (Canada). Dept. of Physics; Cashmore, R J [Oxford Univ. (UK). Dept. of Physics; Davier, M [Lab. de l' Accelerateur Lineaire, Orsay, France; Matthews, J A.J. [Michigan State Univ., East Lansing (USA). Dept. of Physics; Walden, P [British Columbia Univ., Vancouver (Canada). TRIUMF Facility

    1975-11-24

    The results of a wire chamber spectrometer experiment studying anti K*(890) production in the reaction K/sup -/p..-->..K/sup -/..pi../sup +/n at 13 GeV are presented. Strong forward structure is observed for mod(t)cross section. These features are similar to those observed in ..pi../sup -/p..-->..rho/sup 0/n data and are characteristic of ..pi.. exchange. In contrast in the intermediate, mod(t)approximately 0.2 GeV/sup 2/, and large momentum transfer regions anti K*(890) production is dominated by the natural parity rho-A/sub 2/ exchange contribution.

  20. Electron collisions with phenol: Total, integral, differential, and momentum transfer cross sections and the role of multichannel coupling effects on the elastic channel

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Romarly F. da [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, 13083-859 Campinas, São Paulo (Brazil); Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, 09210-580 Santo André, São Paulo (Brazil); Oliveira, Eliane M. de; Lima, Marco A. P. [Instituto de Física “Gleb Wataghin,” Universidade Estadual de Campinas, 13083-859 Campinas, São Paulo (Brazil); Bettega, Márcio H. F. [Departamento de Física, Universidade Federal do Paraná, CP 19044, 81531-990 Curitiba, Paraná (Brazil); Varella, Márcio T. do N. [Instituto de Física, Universidade de São Paulo, CP 66318, 05315-970 São Paulo, São Paulo (Brazil); Jones, Darryl B. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide SA 5001 (Australia); Brunger, Michael J. [School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide SA 5001 (Australia); Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Blanco, Francisco [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, Ciudad Universitaria, 2840 Madrid (Spain); Colmenares, Rafael [Hospital Ramón y Cajal, 28034 Madrid (Spain); and others

    2015-03-14

    We report theoretical and experimental total cross sections for electron scattering by phenol (C{sub 6}H{sub 5}OH). The experimental data were obtained with an apparatus based in Madrid and the calculated cross sections with two different methodologies, the independent atom method with screening corrected additivity rule (IAM-SCAR), and the Schwinger multichannel method with pseudopotentials (SMCPP). The SMCPP method in the N{sub open}-channel coupling scheme, at the static-exchange-plus-polarization approximation, is employed to calculate the scattering amplitudes at impact energies ranging from 5.0 eV to 50 eV. We discuss the multichannel coupling effects in the calculated cross sections, in particular how the number of excited states included in the open-channel space impacts upon the convergence of the elastic cross sections at higher collision energies. The IAM-SCAR approach was also used to obtain the elastic differential cross sections (DCSs) and for correcting the experimental total cross sections for the so-called forward angle scattering effect. We found a very good agreement between our SMCPP theoretical differential, integral, and momentum transfer cross sections and experimental data for benzene (a molecule differing from phenol by replacing a hydrogen atom in benzene with a hydroxyl group). Although some discrepancies were found for lower energies, the agreement between the SMCPP data and the DCSs obtained with the IAM-SCAR method improves, as expected, as the impact energy increases. We also have a good agreement among the present SMCPP calculated total cross section (which includes elastic, 32 inelastic electronic excitation processes and ionization contributions, the latter estimated with the binary-encounter-Bethe model), the IAM-SCAR total cross section, and the experimental data when the latter is corrected for the forward angle scattering effect [Fuss et al., Phys. Rev. A 88, 042702 (2013)].

  1. A survey of cross-section sensitivity analysis as applied to radiation shielding

    International Nuclear Information System (INIS)

    Goldstein, H.

    1977-01-01

    Cross section sensitivity studies revolve around finding the change in the value of an integral quantity, e.g. transmitted dose, for a given change in one of the cross sections. A review is given of the principal methodologies for obtaining the sensitivity profiles-principally direct calculations with altered cross sections, and linear perturbation theory. Some of the varied applications of cross section sensitivity analysis are described, including the practice, of questionable value, of adjusting input cross section data sets so as to provide agreement with integral experiments. Finally, a plea is made for using cross section sensitivity analysis as a powerful tool for analysing the transport mechanisms of particles in radiation shields and for constructing models of how cross section phenomena affect the transport. Cross section sensitivities in the shielding area have proved to be highly problem-dependent. Without the understanding afforded by such models, it is impossible to extrapolate the conclusions of cross section sensitivity analysis beyond the narrow limits of the specific situations examined in detail. Some of the elements that might be of use in developing the qualitative models are presented. (orig.) [de

  2. Theoretical Studies on Photoionization Cross Sections of Solid Gold

    International Nuclear Information System (INIS)

    Ma Xiaoguang; Sun Weiguo; Cheng Yansong

    2005-01-01

    Accurate expression for photoabsorption (photoionization) cross sections of high density system proposed recently is used to study the photoionization of solid gold. The results show that the present theoretical photoionization cross sections have good agreement both in structure and in magnitude with the experimental results of gold crystal. The studies also indicate that both the real part ε' and the imaginary part ε'' of the complex dielectric constant ε, and the dielectric influence function of a nonideal system have rich structures in low energy side with a range about 50 eV, and suggest that the influence of particle interactions of surrounding particles with the photoionized particle on the photoionization cross sections can be easily investigated using the dielectric influence function. The electron overlap effects are suggested to be implemented in the future studies to improve the accuracy of theoretical photoionization cross sections of a solid system.

  3. Hospital Nurses' and Physicians' Use of Information Sources during their Production of Discharge Summaries: A Cross-Sectional Study

    OpenAIRE

    Hellesø, Ragnhild; Sogstad, Maren Kristine Raknes

    2014-01-01

    Hospital nurses' and physicians' production and exchange of accurate information between levels of care are crucial for ensuring safe and seamless care for patients in transition. We report on a study in which we explored hospital providers' use of information sources when they prepared discharge information for colleges in the community health-care sector. In this cross-sectional study, 510 nurses and 236 physicians responded through a questionnaire. Our findings show that nurses and physici...

  4. Review of multigroup nuclear cross-section processing

    Energy Technology Data Exchange (ETDEWEB)

    Trubey, D.K.; Hendrickson, H.R. (comps.)

    1978-10-01

    These proceedings consist of 18 papers given at a seminar--workshop on ''Multigroup Nuclear Cross-Section Processing'' held at Oak Ridge, Tennessee, March 14--16, 1978. The papers describe various computer code systems and computing algorithms for producing multigroup neutron and gamma-ray cross sections from evaluated data, and experience with several reference data libraries. Separate abstracts were prepared for 13 of the papers. The remaining five have already been cited in ERA, and may be located by referring to the entry CONF-780334-- in the Report Number Index. (RWR)

  5. Cross sections for charm production by neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Ushida, N [Aichi Univ. of Education, Kariya (Japan). Dept. of Physics; Kondo, T [Fermi National Accelerator Lab., Batavia, IL (USA); Fujioka, G; Fukushima, J; Takahashi, Y; Tatsumi, S; Yokoyama, C [Kobe Univ. (Japan). Dept. of Physics; Homma, Y; Tsuzuki, Y [Kobe Univ. (Japan). Coll. of Liberal Arts; Bahk, S

    1983-02-03

    The production of charmed particles has been measured using a hybrid emulsion spectrometer in the Fermilab wide-band neutrino beam. The relative cross section for charged current charmed particle production is sigma(v -> ..mu../sup -/c)/sigma(v -> ..mu../sup -/) = 6.5 +- 1.9/1.8%, and the energy dependence of the cross section is presented. One event with charm pair production was observed. A limit of sigma(v -> ..mu..canti c)/sigma(v -> ..mu..c) < 6% (90% CL) is found for the ratio of charged current pair and single charm production.

  6. New techniques for multi-level cross section calculation and fitting

    International Nuclear Information System (INIS)

    Froehner, F.H.

    1980-09-01

    A number of recent developments in multi-level cross section work are described. A new iteration scheme for the conversion of Reich-Moore resonance parameters to Kapur-Peierls parameters allows application of Turing's method for Gaussian broadening of meromorphic functions directly to multi-level cross section expressions, without recourse to the Voigt profiles psi and chi. This makes calculation of Doppler-broadened Reich-Moore and MLBW cross sections practically as fast as SLBW and Adler-Adler cross section calculations involving the Voigt profiles. A convenient distant-level treatment utilizing average resonance parameters is presented. Apart from effectively dealing with edge effects in resonance fitting work it also leads to a simple prescription for the determination of bound levels which reproduce the thermal cross sections correctly. A brief discussion of improved resonance shape fitting techniques is included, with empahsis on the importance of correlated errors and proper use of prior information by application of Bayes' theorem. (orig.) [de

  7. New techniques for multi-level cross section calculation and fitting

    International Nuclear Information System (INIS)

    Froehner, F.H.

    1981-01-01

    A number of recent developments in multi-level cross section work are described. A new iteration scheme for the conversion of Reich-Moore resonance parameters to Kapur-Peierls parameters allows application of Turing's method for Gaussian broadening of meromorphic functions directly to multi-level cross section expressions, without recourse to the Voigt profiles psi and chi. This makes calculation of Doppler-broadened Reich-Moore and MLBW cross sections practically as fast as SLBW and Adler-Adler cross section calculations involving the Voigt profiles. A convenient distant-level treatment utilizing average resonance parameters is presented. Apart from effectively dealing with edge effects in resonance fitting work it also leads to a simple prescription for the determination of bound levels which reproduce the thermal cross sections correctly. A brief discussion of improved resonance shape fitting techniques is included, with emphasis on the importance of correlated errors and proper use of prior information by application of Bayes' theorem

  8. Damage energy and displacement cross sections: survey and sensitivity. [Neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Doran, D.G.; Parkin, D.M.; Robinson, M.T.

    1976-10-01

    Calculations of damage energy and displacement cross sections using the recommendations of a 1972 IAEA Specialists' Meeting are reviewed. The sensitivity of the results to assumptions about electronic energy losses in cascade development and to different choices respecting the nuclear cross sections is indicated. For many metals, relative uncertainties and sensitivities in these areas are sufficiently small that adoption of standard displacement cross sections for neutron irradiations can be recommended.

  9. Quantifying uncertainties in the high-energy neutrino cross-section

    Indian Academy of Sciences (India)

    2012-11-10

    Nov 10, 2012 ... Corresponding author. E-mail: s.sarkar@physics.ox.ac.uk .... i.e. cross-sections in the present case, modern PDF sets provide not only the best-fit PDF, but also .... However, any power-law rise in the cross-section will eventu-.

  10. Use of nuclear reaction models in cross section calculations

    International Nuclear Information System (INIS)

    Grimes, S.M.

    1975-03-01

    The design of fusion reactors will require information about a large number of neutron cross sections in the MeV region. Because of the obvious experimental difficulties, it is probable that not all of the cross sections of interest will be measured. Current direct and pre-equilibrium models can be used to calculate non-statistical contributions to neutron cross sections from information available from charged particle reaction studies; these are added to the calculated statistical contribution. Estimates of the reliability of such calculations can be derived from comparisons with the available data. (3 tables, 12 figures) (U.S.)

  11. ATLAS-ALFA measurements on the total cross section and diffraction

    CERN Document Server

    Mortensen, Simon Stark; The ATLAS collaboration

    2015-01-01

    The measurement of the total pp cross section at the LHC at $\\sqrt{s}=7$ TeV with the ALFA subdetector of ATLAS is presented in this talk. In a special run with $\\beta^*=90$ m beam optics corresponding to an integrated luminosity of 80 $\\text{mb}^{-1}$ the differential elastic cross section is measured in the range from $-t=0.0025\\text{ GeV}^2$ to $-t=0.38\\text{ GeV}^2$. The total cross section $\\sigma(pp\\rightarrow X)$ is extracted using the Optical Theorem by extrapolation of the differential elastic cross section to $t=0\\text{ GeV}^2$. Prospects for diffractive measurements using ALFA to detect the intact proton(s) is also discussed.

  12. Validity of Hansen-Roach cross sections in low-enriched uranium systems

    International Nuclear Information System (INIS)

    Busch, R.D.; O'Dell, R.D.

    1991-01-01

    Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the ''standard'' for use in k eff calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, σ p , for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in cross sections, self shielding of these resonances, and the use of σ p to characterize resonance self shielding. Three prescriptions for calculating σ p are given. Finally, results of several calculations of k eff on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems

  13. Direct measurement of the Rayleigh scattering cross section in various gases

    International Nuclear Information System (INIS)

    Sneep, Maarten; Ubachs, Wim

    2005-01-01

    Using the laser-based technique of cavity ring-down spectroscopy extinction measurements have been performed in various gases straightforwardly resulting in cross sections for Rayleigh scattering. For Ar and N 2 measurements are performed in the range 470-490nm, while for CO 2 cross sections are determined in the wider range 470-570nm. In addition to these gases also for N 2 O, CH 4 , CO, and SF 6 the scattering cross section is determined at 532nm, a wavelength of importance for lidar applications and combustion laser diagnostics. In O 2 the cross section at 532nm is found to depend on pressure due to collision-induced light absorption. The obtained cross sections validate the cross sections for Rayleigh scattering as derived from refractive indices and depolarization ratios through Rayleigh's theory at the few %-level, although somewhat larger discrepancies are found for CO, N 2 O and CH 4

  14. Validity of Hansen-Roach cross sections in low-enriched uranium systems

    International Nuclear Information System (INIS)

    Busch, R.D.; O'Dell, R.D.

    1991-01-01

    Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the standard for use in k eff calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, σ p , for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in cross sections, self shielding of these resonances, and the use of σ p to characterize resonance self shielding. Three prescriptions for calculating σ p are given. Finally, results of several calculations of k eff on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems. (Author)

  15. SENSIT: a cross-section and design sensitivity and uncertainty analysis code

    International Nuclear Information System (INIS)

    Gerstl, S.A.W.

    1980-01-01

    SENSIT computes the sensitivity and uncertainty of a calculated integral response (such as a dose rate) due to input cross sections and their uncertainties. Sensitivity profiles are computed for neutron and gamma-ray reaction cross sections of standard multigroup cross section sets and for secondary energy distributions (SEDs) of multigroup scattering matrices. In the design sensitivity mode, SENSIT computes changes in an integral response due to design changes and gives the appropriate sensitivity coefficients. Cross section uncertainty analyses are performed for three types of input data uncertainties: cross-section covariance matrices for pairs of multigroup reaction cross sections, spectral shape uncertainty parameters for secondary energy distributions (integral SED uncertainties), and covariance matrices for energy-dependent response functions. For all three types of data uncertainties SENSIT computes the resulting variance and estimated standard deviation in an integral response of interest, on the basis of generalized perturbation theory. SENSIT attempts to be more comprehensive than earlier sensitivity analysis codes, such as SWANLAKE

  16. Assessment of Fission Product Cross-Section Data for Burnup Credit Applications

    International Nuclear Information System (INIS)

    Leal, Luiz C; Derrien, Herve; Dunn, Michael E; Mueller, Don

    2007-01-01

    Past efforts by the Department of Energy (DOE), the Electric Power Research Institute (EPRI), the Nuclear Regulatory Commission (NRC), and others have provided sufficient technical information to enable the NRC to issue regulatory guidance for implementation of pressurized-water reactor (PWR) burnup credit; however, consideration of only the reactivity change due to the major actinides is recommended in the guidance. Moreover, DOE, NRC, and EPRI have noted the need for additional scientific and technical data to justify expanding PWR burnup credit to include fission product (FP) nuclides and enable burnup credit implementation for boiling-water reactor (BWR) spent nuclear fuel (SNF). The criticality safety assessment needed for burnup credit applications will utilize computational analyses of packages containing SNF with FP nuclides. Over the years, significant efforts have been devoted to the nuclear data evaluation of major isotopes pertinent to reactor applications (i.e., uranium, plutonium, etc.); however, efforts to evaluate FP cross-section data in the resonance region have been less thorough relative to actinide data. In particular, resonance region cross-section measurements with corresponding R-matrix resonance analyses have not been performed for FP nuclides. Therefore, the objective of this work is to assess the status and performance of existing FP cross-section and cross-section uncertainty data in the resonance region for use in burnup credit analyses. Recommendations for new cross-section measurements and/or evaluations are made based on the data assessment. The assessment focuses on seven primary FP isotopes (103Rh, 133Cs, 143Nd, 149Sm, 151Sm, 152Sm, and 155Gd) that impact reactivity analyses of transportation packages and two FP isotopes (153Eu and 155Eu) that impact prediction of 155Gd concentrations. Much of the assessment work was completed in 2005, and the assessment focused on the latest FP cross-section evaluations available in the

  17. RESEND, Infinitely Dilute Point Cross-Sections Calculation from ENDF/B Resonance Parameter. ADLER, ENDF/B Adler-Adler Resonance Parameter to Point Cross-Sections with Doppler Broadening

    International Nuclear Information System (INIS)

    Bhat, M.R.; Ozer, O.

    1982-01-01

    1 - Description of problem or function: RESEND generates infinitely- dilute, un-broadened, point cross sections in the ENDF format by combining ENDF File 3 background cross sections with points calculated from ENDF File 2 resonance parameter data. ADLER calculates total, capture, and fission cross sections from the corresponding Adler-Adler parameters in the ENDF/B File 2 Version II data and also Doppler-broadens cross sections. 2 - Method of solution: RESEND calculations are done in two steps by two separate sections of the program. The first section does the resonance calculation and stores the results on a scratch file. The second section combines the data from the scratch file with background cross sections and prints the results. ADLER uses the Adler-Adler formalism. 3 - Restrictions on the complexity of the problem: RESEND expects its input to be a standard mode BCD ENDF file (Version II/III). Since the output is also a standard mode BCD ENDF file, the program is limited by the six significant figure accuracy inherent in the ENDF formats. (If the cross section has been calculated at two points so close in energy that only their least significant figures differ, that interval is assumed to have converged, even if other convergence criteria may not be satisfied.) In the unresolved range the cross sections have been averaged over a Porter-Thomas distribution. In some regions the calculated resonance cross sections may be negative. In such cases the standard convergence criterion would cause an unnecessarily large number of points to be produced in the region where the cross section becomes zero. For this reason an additional input convergence criterion (AVERR) may be used. If the absolute value of the cross section at both ends of an interval is determined to be less than AVERR then the interval is assumed to have converged. There are no limitations on the total number of points generated. The present ENDF (Version II/III) formats restrict the total number of

  18. MPI version of NJOY and its application to multigroup cross-section generation

    Energy Technology Data Exchange (ETDEWEB)

    Alpan, A.; Haghighat, A.

    1999-07-01

    Multigroup cross-section libraries are needed in performing neutronics calculations. These libraries are referred to as broad-group libraries. The number of energy groups and group structure are highly dependent on the application and/or user's objectives. For example, for shielding calculations, broad-group libraries such as SAILOR and BUGLE with 47-neutron and 20-gamma energy groups are used. The common procedure to obtain a broad-group library is a three-step process: (1) processing pointwise ENDF (PENDF) format cross sections; (2) generating fine-group cross sections; and (3) collapsing fine-group cross sections to broad-group. The NJOY code is used to prepare fine-group cross sections by processing pointwise ENDF data. The code has several modules, each one performing a specific task. For instance, the module RECONR performs linearization and reconstruction of the cross sections, and the module GROUPR generates multigroup self-shielded cross sections. After fine-group, i.e., groupwise ENDF (GENDF), cross sections are produced, cross sections are self-shielded, and a one-dimensional transport calculation is performed to obtain flux spectra at specific regions in the model. These fluxes are then used as weighting functions to collapse the fine-group cross sections to obtain a broad-group cross-section library. The third step described is commonly performed by the AMPX code system. SMILER converts NJOY GENDF filed to AMPX master libraries, AJAX collects the master libraries. BONAMI performs self-shielding calculations, NITAWL converts the AMPX master library to a working library, XSDRNPM performs one-dimensional transport calculations, and MALOCS collapses fine-group cross sections to broad-group. Finally, ALPO is used to generate ANISN format libraries. In this three-step procedure, generally NJOY requires the largest amount of CPU time. This time varies depending on the user's specified parameters for each module, such as reconstruction tolerances

  19. MPI version of NJOY and its application to multigroup cross-section generation

    International Nuclear Information System (INIS)

    Alpan, A.; Haghighat, A.

    1999-01-01

    Multigroup cross-section libraries are needed in performing neutronics calculations. These libraries are referred to as broad-group libraries. The number of energy groups and group structure are highly dependent on the application and/or user's objectives. For example, for shielding calculations, broad-group libraries such as SAILOR and BUGLE with 47-neutron and 20-gamma energy groups are used. The common procedure to obtain a broad-group library is a three-step process: (1) processing pointwise ENDF (PENDF) format cross sections; (2) generating fine-group cross sections; and (3) collapsing fine-group cross sections to broad-group. The NJOY code is used to prepare fine-group cross sections by processing pointwise ENDF data. The code has several modules, each one performing a specific task. For instance, the module RECONR performs linearization and reconstruction of the cross sections, and the module GROUPR generates multigroup self-shielded cross sections. After fine-group, i.e., groupwise ENDF (GENDF), cross sections are produced, cross sections are self-shielded, and a one-dimensional transport calculation is performed to obtain flux spectra at specific regions in the model. These fluxes are then used as weighting functions to collapse the fine-group cross sections to obtain a broad-group cross-section library. The third step described is commonly performed by the AMPX code system. SMILER converts NJOY GENDF filed to AMPX master libraries, AJAX collects the master libraries. BONAMI performs self-shielding calculations, NITAWL converts the AMPX master library to a working library, XSDRNPM performs one-dimensional transport calculations, and MALOCS collapses fine-group cross sections to broad-group. Finally, ALPO is used to generate ANISN format libraries. In this three-step procedure, generally NJOY requires the largest amount of CPU time. This time varies depending on the user's specified parameters for each module, such as reconstruction tolerances, temperatures

  20. GROUPIE2007, Bondarenko Self-Shielded Cross sections from ENDF/B

    International Nuclear Information System (INIS)

    2007-01-01

    1 - Description of problem or function - GROUPIE reads evaluated data in ENDF/B Format and uses these to calculate unshielded group averaged Cross sections, Bondarenko self-shielded Cross sections, and multiband parameters. The program allows the user to specify arbitrary energy groups and an arbitrary energy-dependent neutron spectrum (weighting function). IAEA0849/15: This version include the updates up to January 30, 2007. Changes in ENDF/B-VII Format and procedures, as well as the evaluations themselves, make it impossible for versions of the ENDF/B pre-processing codes earlier than PREPRO 2007 (2007 Version) to accurately process current ENDF/B-VII evaluations. The present code can handle all existing ENDF/B-VI evaluations through release 8, which will be the last release of ENDF/B-VI. 2 - Modifications from previous versions: Groupie VERS. 2007-1 (Jan. 2007): checked against all ENDF/B-VII; increased page size from 120,000 to 600,000 points. 3 - Method of solution: All integrals are performed analytically; in no case is iteration or any approximate form of integration used. GROUPIE reads either the 0 deg. Kelvin Cross sections or the Doppler broadened Cross sections to calculate the self-shielded Cross sections and multiband parameters for 25 values of the 'background' Cross sections (representing the combined effects of all other isotopes and of leakage). 4 - Restrictions on the complexity of the problem: GROUPIE requires that the energy-dependent neutron spectrum and all Cross sections be given in tabular form, with linear interpolation between tabulated values. There is no limit to the size of the table used to describe the spectrum, so the spectrum may be described in as much detail as required. - If only unshielded averages are calculated, the program can handle up to 3000 groups. If self-shielded averages and/or multiband parameters are calculated, the program can handle up to 175 groups. These limits can easily be extended. - The program only uses the

  1. Bodies with noncircular cross sections and bank-to-turn missiles

    Science.gov (United States)

    Jackson, C. M., Jr.; Sawyer, W. C.

    1992-01-01

    A development status evaluation is presented for the aerodynamics of missile configurations with noncircular cross-sections and bank-to-turn maneuvering systems, giving attention to cases with elliptical and square cross-sections, as well as bodies with variable cross-sections. The assessment of bank-to-turn missile performance notes inherent stability/control problems. A summary and index are provided for aerodynamic data on monoplanar configurations, including those which incorporate airbreathing propulsion systems.

  2. Quality Quantification of Evaluated Cross Section Covariances

    International Nuclear Information System (INIS)

    Varet, S.; Dossantos-Uzarralde, P.; Vayatis, N.

    2015-01-01

    Presently, several methods are used to estimate the covariance matrix of evaluated nuclear cross sections. Because the resulting covariance matrices can be different according to the method used and according to the assumptions of the method, we propose a general and objective approach to quantify the quality of the covariance estimation for evaluated cross sections. The first step consists in defining an objective criterion. The second step is computation of the criterion. In this paper the Kullback-Leibler distance is proposed for the quality quantification of a covariance matrix estimation and its inverse. It is based on the distance to the true covariance matrix. A method based on the bootstrap is presented for the estimation of this criterion, which can be applied with most methods for covariance matrix estimation and without the knowledge of the true covariance matrix. The full approach is illustrated on the 85 Rb nucleus evaluations and the results are then used for a discussion on scoring and Monte Carlo approaches for covariance matrix estimation of the cross section evaluations

  3. The specification of cross exchange rate equations used to test Purchasing Power Parity

    OpenAIRE

    Hunter, J; Simpson, M

    2004-01-01

    The Article considers the speciÞcation of models used to test Pur- chasing Power Parity when applied to cross exchange rates. SpeciÞcally, conventional dynamic models used to test stationarity of the real exchange rate are likely to be misspeciÞed, except when the parameters of each ex- change rate equation are the same

  4. Some problem areas in capture cross-section measurements

    International Nuclear Information System (INIS)

    Moxon, M.C.; Gayther, D.B.; Sowerby, M.G.

    1975-01-01

    This paper outlines some of the problems that have been encountered and are envisaged in the measurement and evaluation of capture cross-sections. Particular emphasis is placed on the cross-sections of the structural materials (Fe, Ni, Cr) used in fast reactors. The topics considered are the influence of scattered neutrons in capture detectors, the determination of background, sample thickness corrections, and the theoretical representation of resonance parameters. (author)

  5. Scattering cross-section of an inhomogeneous plasma cylinder

    International Nuclear Information System (INIS)

    Jiaming Shi; Lijian Qiu; Ling, Y.

    1995-01-01

    Scattering of em waves by the plasma cylinder is of significance in radar target detection, plasma diagnosis, etc. This paper discusses the general method to calculate the scattering cross-section of em waves from a plasma cylinder which is radially inhomogeneous and infinitely long. Numerical results are also provided for several plasma density profiles. The effect of the electron density distribution on the scattering cross-section is investigated

  6. Low energy total cross section of 36Ar

    International Nuclear Information System (INIS)

    Mughabghab, S.F.; Magurno, B.A.

    1975-01-01

    To compare the predictions of the valence model with measured partial radiative widths of 36 Ar an accurate knowledge of the bound-level parameters is required. This is achieved by carrying out a Breit-Wigner parameter fit to the total cross section of 36 Ar measured by Chrien et al and renormalized to the recommended values of the thermal capture and scattering cross sections. (1 figure, 1 table) (U.S.)

  7. An Ada environment for relativistic cross section calculations

    International Nuclear Information System (INIS)

    Nilsson, E.

    1990-01-01

    We have developed an Ada environment adapted to relativistic cross section calculations. Objects such as four-vectors, γ- matrices and propagators are defined as well as operations between these objects. In this environment matrix elements can be expressed in a compact and readable way as Ada code. Unpolarized cross sections are calculated numerically by explicitly summing and averaging over spins and polarizations. A short presentation of the technique is given

  8. Measurement of multinucleon transfer cross-sections

    Indian Academy of Sciences (India)

    Keywords. Ni(C, ), Fe(C, ), =C, C, B, B, Be, Be, Be, Be, Li, Li; = 60 MeV; measured reaction cross-section; elastic scattering angular distribution; deduced transfer probabilities and enhancement factors.

  9. Time-Dependent Wave Packet Dynamics Calculations of Cross Sections for Ultracold Scattering of Molecules

    Science.gov (United States)

    Huang, Jiayu; Liu, Shu; Zhang, Dong H.; Krems, Roman V.

    2018-04-01

    Because the de Broglie wavelength of ultracold molecules is very large, the cross sections for collisions of molecules at ultracold temperatures are always computed by the time-independent quantum scattering approach. Here, we report the first accurate time-dependent wave packet dynamics calculation for reactive scattering of ultracold molecules. Wave packet dynamics calculations can be applied to molecular systems with more dimensions and provide real-time information on the process of bond rearrangement and/or energy exchange in molecular collisions. Our work thus makes possible the extension of rigorous quantum calculations of ultracold reaction properties to polyatomic molecules and adds a new powerful tool for the study of ultracold chemistry.

  10. Sensitivity of LWR fuel cycle costs to uncertainties in detailed thermal cross sections

    International Nuclear Information System (INIS)

    Ryskamp, J.M.; Becker, M.; Harris, D.R.

    1979-01-01

    Cross sections averaged over the thermal energy (< 1 or 2 eV) group have been shown to have an important economic role for light-water reactors. Cost implications of thermal cross section uncertainties at the few-group level were reported earlier. When it has been determined that costs are sensitive to a specific thermal-group cross section, it becomes desirable to determine how specific energy-dependent cross sections influence fuel cycle costs. Multigroup cross-section sensitivity coefficients vary with fuel exposure. By changing the shape of a cross section displayed on a view-tube through an interactive graphics system, one can compute the change in few-group cross section using the exposure dependent sensitivity coefficients. With the changed exposure dependent few-group cross section, a new fuel cycle cost is computed by a sequence of batch depletion, core analysis, and fuel batch cost code modules. Fuel cycle costs are generally most sensitive to cross section uncertainties near the peak of the hardened Maxwellian flux

  11. CASTHY, Statistical Model for Neutron Cross-Sections and Gamma-Ray Spectra

    International Nuclear Information System (INIS)

    Igarasi, Sin-iti; Fukahori, Tokio

    1998-01-01

    Description of program or function: CASTHY calculates neutron cross sections of total, shape elastic scattering and compound nucleus formation with the optical model, and compound elastic, inelastic and capture cross sections by the statistical model. The other cross sections, such as (n,2n), (n,p), (n,f) reactions are treated as cross sections of competing processes, and their sum is given through input data. Capture gamma-ray spectra can also be calculated. The branching ratio for primary transition can be treated in a particular way, if required

  12. Absolute photoionization cross-section of the propargyl radical

    Energy Technology Data Exchange (ETDEWEB)

    Savee, John D.; Welz, Oliver; Taatjes, Craig A.; Osborn, David L. [Sandia National Laboratories, Combustion Research Facility, Livermore, California 94551 (United States); Soorkia, Satchin [Institut des Sciences Moleculaires d' Orsay, Universite Paris-Sud 11, Orsay (France); Selby, Talitha M. [Department of Chemistry, University of Wisconsin, Washington County Campus, West Bend, Wisconsin 53095 (United States)

    2012-04-07

    Using synchrotron-generated vacuum-ultraviolet radiation and multiplexed time-resolved photoionization mass spectrometry we have measured the absolute photoionization cross-section for the propargyl (C{sub 3}H{sub 3}) radical, {sigma}{sub propargyl}{sup ion}(E), relative to the known absolute cross-section of the methyl (CH{sub 3}) radical. We generated a stoichiometric 1:1 ratio of C{sub 3}H{sub 3} : CH{sub 3} from 193 nm photolysis of two different C{sub 4}H{sub 6} isomers (1-butyne and 1,3-butadiene). Photolysis of 1-butyne yielded values of {sigma}{sub propargyl}{sup ion}(10.213 eV)=(26.1{+-}4.2) Mb and {sigma}{sub propargyl}{sup ion}(10.413 eV)=(23.4{+-}3.2) Mb, whereas photolysis of 1,3-butadiene yielded values of {sigma}{sub propargyl}{sup ion}(10.213 eV)=(23.6{+-}3.6) Mb and {sigma}{sub propargyl}{sup ion}(10.413 eV)=(25.1{+-}3.5) Mb. These measurements place our relative photoionization cross-section spectrum for propargyl on an absolute scale between 8.6 and 10.5 eV. The cross-section derived from our results is approximately a factor of three larger than previous determinations.

  13. Formation cross section of iron-60 with reactor neutrons in 59Fe(n, γ)60Fe reaction

    International Nuclear Information System (INIS)

    Sato, T.; Suzuki, T.

    1993-01-01

    Ingrowth of 60 Co radioactivity in an iron sample irradiated in a nuclear reactor has been measured for determination of formation cross section of 60 Fe in the 59 Fe(n, γ) 60 Fe reaction with reactor neutrons. After 5 years cooling, the irradiated iron was purified from 60 Co and other radioactive nuclides by an anion exchange separation method and isopropyl ether extraction in hydrochloric acid. The amount of 60 Co ingrowth was measured by γ-spectrometry using a Ge-detector coupled to a multichannel pulse height analyzer 4 years after the purification of iron. Neutron flux of the irradiation position was calculated from the amount of 55 Fe produced. The observed value of 12.5 ± 2.8 barn is slightly greater than reported value for burnup cross section of 59 Fe(n, x)X, where x refers γ, α, d, p and 2n, and X is any nuclide produced by the above reactions. (author) 8 refs.; 2 tabs

  14. Light stops emerging in WW cross section measurements?

    International Nuclear Information System (INIS)

    Rolbiecki, Krzysztof

    2013-03-01

    Recent ATLAS and CMS measurements show a slight excess in the WW cross section measurement. While still consistent with the Standard Model within 1-2σ, the excess could be also a first hint of physics beyond the Standard Model. We argue that this effect could be attributed to the production of scalar top quarks within supersymmetric models. The stops of m t 1 ∝200 GeV has the right cross section and under some assumptions can significantly contribute to the final state of two leptons and missing energy. We scan this region of parameter space to find particle masses preferred by the WW cross section measurements. Taking one sample benchmark point we show that it can be consistent with low energy observables and Higgs sector measurements and propose a method to distinguish supersymmetric signal from the Standard Model contribution.

  15. Self-scattering cross-section of molecules in a beam

    International Nuclear Information System (INIS)

    Lou, Y.S.

    1974-01-01

    Molecular collision cross-section has always been measured by the beam scattering method, or by the measurements of thermal conductivity and/or viscosity coefficient, etc. The cross-section thus obtained has been found to be different, qualitatively, from that of the self-scattering of the molecules moving within a molecular beam. By perturbing the zeroth order solution of the Boltzmann equation with a B-G-K kinetic model for the gas upstream to the orifice, and performing particle scattering calculation for molecules within the beam downstream to the orifice, such self-scattering collision cross-section can be determined from the experimental data of velocity distribution functions of molecules in the beam

  16. Actinide neutron-induced fission cross section measurements at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Tovesson, Fredrik K [Los Alamos National Laboratory; Laptev, Alexander B [Los Alamos National Laboratory; Hill, Tony S [INL

    2010-01-01

    Fission cross sections of a range of actinides have been measured at the Los Alamos Neutron Science Center (LANSCE) in support of nuclear energy applications in a wide energy range from sub-thermal energies up to 200 MeV. A parallel-plate ionization chamber are used to measure fission cross sections ratios relative to the {sup 235}U standard while incident neutron energies are determined using the time-of-flight method. Recent measurements include the {sup 233,238}U, {sup 239-242}Pu and {sup 243}Am neutron-induced fission cross sections. Obtained data are presented in comparison with ex isting evaluations and previous data.

  17. Inclusive cross sections in AA collisions at high energies

    International Nuclear Information System (INIS)

    Braun, M.A.

    1988-01-01

    Inclusive cross sections in AA collisions at high energies are considered in the Glauber multiple scattering theory taking into account many-nucleon collisions. Correspondence is found between the AA amplitude and the effective action of the two-dimensional quantum field theory with exponential interaction. The tree and one-loop contributions are calculated in this formalism. The rules are derived, which relate the absorption part of the AA-collision amplitudes associated with various inclusive cross sections to the absorption parts of NN amplitudes. These rules generalize the well-known Agranowsky-Gribov-Kanchelli rules for hh and hA collisions. Formulas are written for single and double inclusive cross sections in AA collisions

  18. Cross-Sectional Transport Imaging in a Multijunction Solar Cell

    Energy Technology Data Exchange (ETDEWEB)

    Haegel, Nancy M.; Ke, Chi-Wen; Taha, Hesham; Guthrey, Harvey; Fetzer, C. M.; King, Richard

    2015-06-14

    Combining highly localized electron-beam excitation at a point with the spatial resolution capability of optical near-field imaging, we have imaged carrier transport in a cross-sectioned multijunction (GaInP/GaInAs/Ge) solar cell. We image energy transport associated with carrier diffusion throughout the full width of the middle (GaInAs) cell and luminescent coupling from point excitation in the top cell GaInP to the middle cell. Supporting cathodoluminescence and near-field photoluminescence measurements demonstrate excitation-dependent Fermi level splitting effects that influence cross-sectioned spectroscopy results as well as transport limitations on the spatial resolution of cross-sectional measurements.

  19. Total cross section for relativistic positronium interaction with atom

    International Nuclear Information System (INIS)

    Pak, A.S.; Tarasov, A.V.

    1985-01-01

    Total cross sections of interaction of positronium relativistic atoms with atoms are calculated. Calculations are conducted within the framework of potential theory in Born approximaton. Contributions in total cross section of coherent (σsub(coh)) and incoherent (σsub(inc)) parts are analyzed. It is shown that for light elements σsub(inc) value is comparable with σsub(coh), and for heavy ones the ratio σsub(inc)/σsub(coh) sufficiently exceeds Zsup(-1) (Z-charge of the atomic nucleus. Numerical calculation results are presented. A conclusion is made on importance of the coherent part account during the calculation of total cross sections

  20. Cross sections for electron-impact excitation of argon by fourier transform spectroscopy

    International Nuclear Information System (INIS)

    Chilton, J.E.; Boffard, J.B.; Chun C.L.

    1996-01-01

    The authors report absolute measurements of electron-impact excitation cross sections out of the ground level to the ten levels in the 3p 5 4p configuration of argon. The apparent excitation cross sections are determined by measuring the optical cross sections for the emission lines in the 3p 5 4p → 3p 5 4s manifold. For cascade corrections the authors measured the optical cross sections for the various 3p 5 5s → 3p 5 4p and 3p 5 4p infrared lines using a Fourier transform weak emission spectrometer to obtain the direct excitation cross sections from the optical data. Although the optical cross sections vary with pressure in the regime of 0.1 to 6 mTorr, the direct cross sections remain invariant. These pressure effects are understood within the framework of a radiation-reabsorption model. The excitation functions for the different transitions are also found to show considerable variation in shape

  1. The 10B(n,α)7Li cross section

    International Nuclear Information System (INIS)

    1997-01-01

    The data base relevant to an evaluation of the 10 B(n,α) standard cross sections have been improved through interlaboratory collaboration. Changes in the evaluated 10 B(n,α) cross sections resulted form the measurements made since the ENDF/B-VI evaluation have been estimated. 12 refs, 4 figs

  2. Modelling interaction cross sections for intermediate and low energy ions

    International Nuclear Information System (INIS)

    Toburen, L.H.; Shinpaugh, J.L.; Justiniano, E.L.B.

    2002-01-01

    When charged particles slow in tissue they undergo electron capture and loss processes than can have profound effects on subsequent interaction cross sections. Although a large amount of data exists for the interaction of bare charged particles with atoms and molecules, few experiments have been reported for these 'dressed' particles. Projectile electrons contribute to an impact-parameter-dependent screening of the projectile charge that precludes straightforward scaling of energy loss cross sections from those of bare charged particles. The objective of this work is to develop an analytical model for the energy-loss-dependent effects of screening on differential ionisation cross sections that can be used in track structure calculations for high LET ions. As a first step a model of differential ionisation cross sections for bare ions has been combined with a simple screening model to explore cross sections for intermediate and low energy dressed ions in collisions with atomic and molecular gas targets. The model is described briefly and preliminary results compared to measured electron energy spectra. (author)

  3. Energy-averaged neutron cross sections of fast-reactor structural materials

    International Nuclear Information System (INIS)

    Smith, A.; McKnight, R.; Smith, D.

    1978-02-01

    The status of energy-averaged cross sections of fast-reactor structural materials is outlined with emphasis on U.S. data programs in the neutron-energy range 1-10 MeV. Areas of outstanding accomplishment and significant uncertainty are noted with recommendations for future efforts. Attention is primarily given to the main constituents of stainless steel (e.g., Fe, Ni, and Cr) and, secondarily, to alternate structural materials (e.g., V, Ti, Nb, Mo, Zr). Generally, the mass regions of interest are A approximately 50 to 60 and A approximately 90 to 100. Neutron total and elastic-scattering cross sections are discussed with the implication on the non-elastic-cross sections. Cross sections governing discrete-inelastic-neutron-energy transfers are examined in detail. Cross sections for the reactions (n;p), (n;n',p), (n;α), (n;n',α) and (n;2n') are reviewed in the context of fast-reactor performance and/or diagnostics. The primary orientation of the discussion is experimental with some additional attention to the applications of theory, the problems of evaluation and the data sensitivity of representative fast-reactor systems

  4. Thermal neutron capture cross sections of tellurium isotopes

    International Nuclear Information System (INIS)

    Tomandl, I.; Honzatko, J.; Egidy, T. von; Wirth, H.-F.; Belgya, T.; Lakatos, M.; Szentmiklosi, L.; Revay, Zs.; Molnar, G.L.; Firestone, R.B.; Bondarenko, V.

    2003-01-01

    New values for thermal neutron capture cross sections of the tellurium isotopes 122 Te, 124 Te, 125 Te, 126 Te, 128 Te, and 130 Te are reported. These values are based on a combination of newly determined partial γ-ray cross sections obtained from experiments on targets contained natural Te and γ intensities per capture of individual Te isotopes. Isomeric ratios for the thermal neutron capture on the even tellurium isotopes are also given

  5. Thermal neutron capture cross sections of tellurium isotopes

    International Nuclear Information System (INIS)

    Tomandl, I.; Honzatko, J.; Egidy, T. von; Wirth, H.-F.; Belgya, T.; Lakatos, M.; Szentmiklosi, L.; Revay, Zs.; Molnar, G.L.; Firestone, R.B.; Bondarenko, V.

    2004-01-01

    New values for thermal neutron capture cross sections of the tellurium isotopes 122Te, 124Te, 125Te, 126Te, 128Te, and 130Te are reported. These values are based on a combination of newly determined partial g-ray cross sections obtained from experiments on targets contained natural Te and gamma intensities per capture of individual Te isotopes. Isomeric ratios for the thermal neutron capture on the even tellurium isotopes are also given

  6. Thermal neutron capture cross sections of tellurium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Tomandl, I.; Honzatko, J.; von Egidy, T.; Wirth, H.-F.; Belgya, T.; Lakatos, M.; Szentmiklosi, L.; Revay, Zs.; Molnar, G.L.; Firestone, R.B.; Bondarenko, V.

    2004-03-01

    New values for thermal neutron capture cross sections of the tellurium isotopes 122Te, 124Te, 125Te, 126Te, 128Te, and 130Te are reported. These values are based on a combination of newly determined partial g-ray cross sections obtained from experiments on targets contained natural Te and gamma intensities per capture of individual Te isotopes. Isomeric ratios for the thermal neutron capture on the even tellurium isotopes are also given.

  7. a cross-sectional analytic study 2014

    African Journals Online (AJOL)

    Assessment of HIV/AIDS comprehensive correct knowledge among Sudanese university: a cross-sectional analytic study 2014. ... There are limited studies on this topic in Sudan. In this study we investigated the Comprehensive correct ...

  8. Penning ionization cross sections of excited rare gas atoms

    International Nuclear Information System (INIS)

    Ukai, Masatoshi; Hatano, Yoshihiko.

    1988-01-01

    Electronic energy transfer processes involving excited rare gas atoms play one of the most important roles in ionized gas phenomena. Penning ionization is one of the well known electronic energy transfer processes and has been studied extensively both experimentally and theoretically. The present paper reports the deexcitation (Penning ionization) cross sections of metastable state helium He(2 3 S) and radiative He(2 1 P) atoms in collision with atoms and molecules, which have recently been obtained by the authors' group by using a pulse radiolysis method. Investigation is made of the selected deexcitation cross sections of He(2 3 S) by atoms and molecules in the thermal collisional energy region. Results indicate that the cross sections are strongly dependent on the target molecule. The deexcitation probability of He(2 3 S) per collision increases with the excess electronic energy of He(2 3 S) above the ionization potential of the target atom or molecule. Another investigation, made on the deexcitation of He(2 1 P), suggests that the deexcitation cross section for He(2 1 P) by Ar is determined mainly by the Penning ionization cross section due to a dipole-dipole interaction. Penning ionization due to the dipole-dipole interaction is also important for deexcitation of He(2 1 P) by the target molecules examined. (N.K.)

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

    International Nuclear Information System (INIS)

    Sagrado Garcia, Inmaculada C.

    2006-01-01

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

  10. Electron-collision excitation cross section of the silver atom

    International Nuclear Information System (INIS)

    Krasavin, A.Y.; Kuchenev, A.N.; Smirnov, Y.M.

    1983-01-01

    The cross sections for direct excitation by electron collision were measured for fifteen transitions of the silver atom. For thirteen of these transitions the optical excitation functions were recorded, varying the energy of the exciting electrons from the threshold energy to 250 eV. The operating region of the spectrum was 2000--5500 A. The excitation cross sections of the two principal lines exceeded the excitation cross sections of all the remaining lines by more than an order of magnitude. Reabsorption of the resonance lines was detected from the change in the ratio of intensities of the lines at 3280.68 and 3382.89 A, and so their intensity has been corrected relative to the intensities of the nonreabsorbed lines. All radiative transitions, with the exception of resonance transitions, participate in cascade population of the lowest resonance levels, making it possible to determine the resulting direct excitation cross sections of the 5p 2 P/sub 1/2/ and 5p 2 P/sub 3/2/ levels from the ground state of the silver atom. The part played by cascade population of the resonance levels is not large and is 2 P/sub 3/2/ level, and 10% for the 5p 2 P/sub 1/2/ level, of the excitation cross sections of the corresponding resonance transitions

  11. Measurement of aluminum activation cross section and gas production cross section for 0.4 and 3-GeV protons

    Directory of Open Access Journals (Sweden)

    Meigo Shin-ichiro

    2017-01-01

    Full Text Available To estimate the lifetime and the radiation dose of the proton beam window used in the spallation neutron source at J-PARC, it is necessary to understand the accuracy of the production cross section of 3-GeV protons. To obtain data on aluminum, the reaction cross section of aluminum was measured at the entrance of the beam dump placed in the 3-GeV proton synchrotron. Owing to the use of well-calibrated current transformers and a well-collimated beam, the present data has good accuracy. After irradiation, the cross sections of Al(p,x7Be, Al(p,x22Na-22 and Al(p,x24Na were obtained by gamma-ray spectroscopy using a Ge detector. It was found that the evaluated data of JENDL/HE-2007 agree well with the current experimental data, whereas intra-nuclear cascade models (Bertini, INCL-4.6, and JAM with the GEM statistical decay model underestimate by about 30% in general. Moreover, gas production, such as T and He, and the cross sections were measured for carbon, which was utilized as the muon production target in J-PARC. The experiment was performed with 3-GeV proton having beam power of 0.5 MW, and the gasses emitted in the process were observed using a quadrupole mass spectrometer in the vacuum line for beam transport to the mercury target. It was found that the JENDL/HE-2007 data agree well with the present experimental data.

  12. Computation of Resonance-Screened Cross Section by the Dorix-Speng System

    Energy Technology Data Exchange (ETDEWEB)

    Haeggblom, H

    1968-09-15

    The report describes a scheme for computation of group cross sections for fast reactors in energy regions where the resonance structure of the cross sections may be dense. A combination of the programmes Dorix and Speng is then used. Dorix calculates group cross sections for each resonance absorber separately. The interaction between resolved resonances in the same isotope is treated using a method described in a separate report. The interaction between correlated and non-correlated resonances in the unresolved region is also considered. By a Dorix calculation we obtain effective microscopic cross sections which are then read in on a library tape. This library contains both point-by-point data and group cross sections and is used in the Speng programme for computation of spectrum and/or macroscopic cross sections. The resonance interaction between different isotopes is computed in Speng by the same method as was used in the Dorix programme for non-correlated unresolved resonances. Consideration is also given to the width of the resonances compared to the energy loss by a neutron colliding with some of the scattering elements.

  13. Computation of Resonance-Screened Cross Section by the Dorix-Speng System

    International Nuclear Information System (INIS)

    Haeggblom, H.

    1968-09-01

    The report describes a scheme for computation of group cross sections for fast reactors in energy regions where the resonance structure of the cross sections may be dense. A combination of the programmes Dorix and Speng is then used. Dorix calculates group cross sections for each resonance absorber separately. The interaction between resolved resonances in the same isotope is treated using a method described in a separate report. The interaction between correlated and non-correlated resonances in the unresolved region is also considered. By a Dorix calculation we obtain effective microscopic cross sections which are then read in on a library tape. This library contains both point-by-point data and group cross sections and is used in the Speng programme for computation of spectrum and/or macroscopic cross sections. The resonance interaction between different isotopes is computed in Speng by the same method as was used in the Dorix programme for non-correlated unresolved resonances. Consideration is also given to the width of the resonances compared to the energy loss by a neutron colliding with some of the scattering elements

  14. Mixed Legendre moments and discrete scattering cross sections for anisotropy representation

    International Nuclear Information System (INIS)

    Calloo, A.; Vidal, J. F.; Le Tellier, R.; Rimpault, G.

    2012-01-01

    This paper deals with the resolution of the integro-differential form of the Boltzmann transport equation for neutron transport in nuclear reactors. In multigroup theory, deterministic codes use transfer cross sections which are expanded on Legendre polynomials. This modelling leads to negative values of the transfer cross section for certain scattering angles, and hence, the multigroup scattering source term is wrongly computed. The first part compares the convergence of 'Legendre-expanded' cross sections with respect to the order used with the method of characteristics (MOC) for Pressurised Water Reactor (PWR) type cells. Furthermore, the cross section is developed using piecewise-constant functions, which better models the multigroup transfer cross section and prevents the occurrence of any negative value for it. The second part focuses on the method of solving the transport equation with the above-mentioned piecewise-constant cross sections for lattice calculations for PWR cells. This expansion thereby constitutes a 'reference' method to compare the conventional Legendre expansion to, and to determine its pertinence when applied to reactor physics calculations. (authors)

  15. Fusion cross sections from measurements of delayed X-rays

    International Nuclear Information System (INIS)

    Pacheco, A.J.; Gregorio, D.E. di; Fernandez Niello, J.O; Elgue, M.

    1988-01-01

    The program XRAY is a FORTRAN 77 computer code for the extraction of fusion cross sections from delayed X-ray measurements. This is accomplished by calculating the theoretical expressions of the time dependence of the evaporation-residue cross sections and taking them as adjustable parameters in a χ 2 minimization procedure. (orig.)

  16. Analytical Absorption Cross-Section for Photon by a Hydrogen 2s Atom

    International Nuclear Information System (INIS)

    Ndinya, Boniface Otieno; Okeyo, Stephen Onyango

    2011-01-01

    We calculate the absorption cross-section for photon by a hydrogen 2s atom using the quantum-classical approximation for the total photo cross-section of many electron atoms. With the application of the first-order term of the Baker-Hausdorf expansion, the absorption cross-section for the hydrogen 2s atom decreases to a minimum, the Cooper pair minimum, at low photon energy. Such a minimum is absent in the exact absorption cross-section for photon by a hydrogen 2s atom. We have extended the calculation for the absorption cross-section of the hydrogen 2s atom using the quantum-classical approximation for the total photo cross-section of many electron to include the second-order term of the Baker-Hausdorf expansion and observed a great reduction in the dip associated with the Cooper pair minimum at the zero crossing. (atomic and molecular physics)

  17. Radar cross section

    CERN Document Server

    Knott, Gene; Tuley, Michael

    2004-01-01

    This is the second edition of the first and foremost book on this subject for self-study, training, and course work. Radar cross section (RCS) is a comparison of two radar signal strengths. One is the strength of the radar beam sweeping over a target, the other is the strength of the reflected echo sensed by the receiver. This book shows how the RCS ?gauge? can be predicted for theoretical objects and how it can be measured for real targets. Predicting RCS is not easy, even for simple objects like spheres or cylinders, but this book explains the two ?exact? forms of theory so well that even a

  18. Measurement of np→dπ0 cross sections very near threshold

    International Nuclear Information System (INIS)

    Hutcheon, D.A.; Abegg, R.; Greeniaus, L.G.; Miller, C.A.; Korkmaz, E.; Moss, G.A.; Edwards, G.W.R.; Mack, D.; Olsen, W.C.; Ye, Y.

    1989-06-01

    We have measured np→dπ 0 cross sections at ten beam energies within 16 MeV of threshold. Total cross sections followed closely the relationship σ tot (np→dπ 0 ) = (1/2)[(184±5)η 3 ]μb, where η is the c.m. pion momentum in units of m π c. The differential cross sections are anisotropic at only 1 MeV (c.m.) above threshold. These results are predicted by Faddeev model calculations and by a perturbative model. Our cross sections are in fair agreement with previous π + d→pp data. (Author) 12 refs., tab., 4 figs

  19. Mid-IR Absorption Cross-Section Measurements of Hydrocarbons

    KAUST Repository

    Alrefae, Majed Abdullah

    2013-05-01

    Laser diagnostics are fast-response, non-intrusive and species-specific tools perfectly applicable for studying combustion processes. Quantitative measurements of species concentration and temperature require spectroscopic data to be well-known at combustion-relevant conditions. Absorption cross-section is an important spectroscopic quantity and has direct relation to the species concentration. In this work, the absorption cross-sections of basic hydrocarbons are measured using Fourier Transform Infrared (FTIR) spectrometer, tunable Difference Frequency Generation laser and fixed wavelength helium-neon laser. The studied species are methane, methanol, acetylene, ethylene, ethane, ethanol, propylene, propane, 1-butene, n-butane, n-pentane, n-hexane, and n-heptane. The Fourier Transform Infrared (FTIR) spectrometer is used for the measurements of the absorption cross-sections and the integrated band intensities of the 13 hydrocarbons. The spectral region of the spectra is 2800 – 3400 cm-1 (2.9 – 3.6 μm) and the temperature range is 673 – 1100 K. These valuable data provide huge opportunities to select interference-free wavelengths for measuring time-histories of a specific species in a shock tube or other combustion systems. Such measurements can allow developing/improving chemical kinetics mechanisms by experimentally determining reaction rates. The Difference Frequency Generation (DFG) laser is a narrow line-width, tunable laser in the 3.35 – 3.53 μm wavelength region which contains strong absorption features for most hydrocarbons due to the fundamental C-H vibrating stretch. The absorption cross-sections of propylene are measured at seven different wavelengths using the DFG laser. The temperature range is 296 – 460 K which is reached using a Reflex Cell. The DFG laser is very attractive for kinetic studies in the shock tube because of its fast time response and the potential possibility of making species-specific measurements. The Fixed wavelength

  20. Resonance charge exchange processes

    International Nuclear Information System (INIS)

    Duman, E.L.; Evseev, A.V.; Eletskij, A.V.; Radtsig, A.A.; Smirnov, B.M.

    1979-01-01

    The calculation results for the resonance charge exchange cross sections for positive and negative atomic and molecular ions are given. The calculations are performed on the basis of the asymptotic theory. The factors affecting the calculation accuracy are analysed. The calculation data for 28 systems are compared with the experiment

  1. Cross sections for fast-neutron interaction with ytterbium isotopes

    International Nuclear Information System (INIS)

    Luo, Junhua; Liu, Rong; Jiang, Li; Ge, Suhong; Liu, Zhenlai; Sun, Guihua

    2013-01-01

    Highlights: ► The cross sections for the (n,x) reactions on ytterbium isotopes have been measured. ► Mono-energetic neutron beams using the D + T reaction; Energies: 13.5 and 14.8 MeV. ► Neutron cross-section measurements by means of the activation technique. ► Reference reactions 93 Nb(n,2n) 92m Nb and 27 (n,α) 24 Na. ► Data for 172 Yb(n,p) 172 Tm and 176 Yb(n,d * ) 175 Tm are reported for the first time. - Abstract: Measurements of (n,2n), (n,p), and (n,d * ) (The expression (n,d * ) cross section used in this work includes a sum of (n,d), (n,np) and (n,pn) cross sections.) reaction cross-sections on ytterbium isotopes have been carried out in the range of 13.5–14.8 MeV using the activation technique. The monoenergetic neutron beams were produced via the 3 H(d,n) 3 He reaction. The neutron energies of different directions were determined using the Nb/Zr method. Samples were activated along with along with Nb and Al monitor foils to determine the incident neutron flux. Data are reported for the following reactions: 168 Yb(n,2n) 167 Yb, 170 Yb(n,2n) 169m+g Yb, 176 Yb(n,2n) 175m+g Yb, 172 Yb(n,p) 172 Tm, 173 Yb(n,p) 173 Tm, 176 Yb(n,d * ) 175 Tm, 174 Yb(n,p) 174 Tm, and 176 Yb(n,p) 176 Tm. The experimentally deduced cross-sections are compared with the existing experimental data. Furthermore, theoretical statistical model, based on the Hauser–Feshbach formalism, have been carried out using the HFTT

  2. Systematics in total (n,2n) cross sections at 14 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Garg, K C; Khurana, C S [Punjabi Univ., Patiala (India). Nuclear Science Labs.

    1976-11-20

    The 14-15 MeV (n,2n) cross sections are found to depend mainly on the asymmetry parameter and the Q-value. No shell effects are found to exist in these cross sections. The total (n,2n) cross sections are found to be well predicted by an empirical relation which takes into account the Q-value and the asymmetry parameter in addition to the geometrical cross section.

  3. Summary of activation cross section measurements at FNS

    International Nuclear Information System (INIS)

    Ikeda, Y.; Konno, C.; Kasugai, Y.; Kumar, A.

    1996-01-01

    Neutron activation cross sections around 14 MeV for seventeen reactions have been measured at the FNS facility in JAERI in order to provide experimental data meeting the requirement in the radioactive wastes disposal assessment in the D-T fusion reactor. This report summarizes contributing data measured in several phases of experiments to the IAEA-CRP on ''Activation Cross sections for the Generation of Long-Lived radionuclides of Importance in Fusion Reactor Technology''. (author). 18 refs, 1 tab

  4. Measurement of proton inelastic scattering cross sections on fluorine

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, M., E-mail: chiari@fi.infn.it [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy); Caciolli, A. [Department of Physics and Astronomy, University of Padua and INFN Padua, Padova (Italy); Calzolai, G. [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy); Climent-Font, A. [CMAM, Universidad Autonoma de Madrid, Madrid (Spain); Lucarelli, F.; Nava, S. [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy)

    2016-10-01

    Differential cross-sections for proton inelastic scattering on fluorine, {sup 19}F(p,p’){sup 19}F, from the first five excited levels of {sup 19}F at 110, 197, 1346, 1459 and 1554 keV were measured for beam energies from 3 to 7 MeV at a scattering angle of 150° using a LiF thin target (50 μg/cm{sup 2}) evaporated on a self-supporting C thin film (30 μg/cm{sup 2}). Absolute differential cross-sections were calculated with a method not dependent on the absolute values of collected beam charge and detector solid angle. The validity of the measured inelastic scattering cross sections was then tested by successfully reproducing EBS spectra collected from a thick Teflon (CF{sub 2}) target. As a practical application of these measured inelastic scattering cross sections in elastic backscattering spectroscopy (EBS), the feasibility of quantitative light element (C, N and O) analysis in aerosol particulate matter samples collected on Teflon by EBS measurements and spectra simulation is demonstrated.

  5. Generation of neutron scattering cross sections for silicon dioxide

    International Nuclear Information System (INIS)

    Ramos, R; Marquez Damian, J.I; Granada, J.R.; Cantargi, F

    2009-01-01

    A set of neutron scattering cross sections for silicon and oxygen bound in silicon dioxide were generated and validated. The cross sections were generated in the ACE format for MCNP using the nuclear data processing system NJOY, and the validation was done with published experimental data. This cross section library was applied to the calculation of five critical configurations published in the benchmark Critical Experiments with Heterogeneous Compositions of Highly Enriched Uranium, Silicon Dioxide and Polyethylene. The original calculations did not use the thermal scattering libraries generated in this work and presented significant differences with the experimental results. For this reason, the newly generated library was added to the input and the multiplication factor for each configuration was recomputed. The utilization of the thermal scattering libraries did not result in an improvement of the computational results. Based on this we conclude that integral experiments to validate this type of thermal cross sections need to be designed with a higher influence of thermal scattering in the measured result, and the experiments have to be performed under more controlled conditions. [es

  6. Light stops emerging in WW cross section measurements?

    Energy Technology Data Exchange (ETDEWEB)

    Rolbiecki, Krzysztof [IFT-UAM/CSIC, Madrid (Spain). Inst. de Fisica Teorica; Sakurai, Kazuki [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-03-15

    Recent ATLAS and CMS measurements show a slight excess in the WW cross section measurement. While still consistent with the Standard Model within 1-2{sigma}, the excess could be also a first hint of physics beyond the Standard Model. We argue that this effect could be attributed to the production of scalar top quarks within supersymmetric models. The stops of m{sub t{sub 1}}{proportional_to}200 GeV has the right cross section and under some assumptions can significantly contribute to the final state of two leptons and missing energy. We scan this region of parameter space to find particle masses preferred by the WW cross section measurements. Taking one sample benchmark point we show that it can be consistent with low energy observables and Higgs sector measurements and propose a method to distinguish supersymmetric signal from the Standard Model contribution.

  7. Pion photoproduction cross section at large momentum transfer

    Energy Technology Data Exchange (ETDEWEB)

    Sjoegren, Johan [Univ. of Glasgow, Scotland, United Kingdom

    2015-02-27

    The Real Compton Scattering experiment was performed in Hall A at the Thomas Jefferson National Accelerator Facility. It was designed to measure, for Compton scattering and π0-photoproduction, the differential cross section over a range of kinematic points and the polarisation transfer to the proton at a single kinematic point. The full range of the experiment in Mandelstam variables t and s was 1.6-6.46 GeV2 and 4.82-10.92 GeV2 respectively with beam energies of 2-6 GeV. The motivation for the experiment is to test the cross section and polarisation transfer predictions of perturbative QCD versus that of predictions from Generalised Parton Distribution models. This thesis will give an overview of the pertinent theory, experimental setup in Hall A and the extracting of the π0-photoproduction cross section.

  8. Charge transfer cross sections for dysprosium and cerium

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Hajime; Tamura, Koji; Okazaki, Tetsuji; Shibata, Takemasa [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-06-01

    Symmetric resonant charge transfer cross sections between singly ionized ions and the parent atoms were measured for dysprosium and cerium in the impact energy of 200-2000eV. The cross sections were determined from the ratio between the number of ions produced by charge transfer and those in primary ion beam. The primary ion beam was produced by a laser ion source in which their atoms were ionized by laser resonant photo-ionization. The slow ions produced by charge transfer and fast primary ions were detected with Faraday cups. The obtained cross sections were (1.82{+-}0.14) x 10{sup -14} cm{sup 2} for dysprosium and (0.88{+-}0.12) x 10{sup -14} cm{sup 2} for cerium in the above energy range. The difference of these values can mostly be explained by considering the electron configurations of these atoms and ions. (author)

  9. Charge transfer cross sections for dysprosium and cerium

    International Nuclear Information System (INIS)

    Adachi, Hajime; Tamura, Koji; Okazaki, Tetsuji; Shibata, Takemasa

    1998-06-01

    Symmetric resonant charge transfer cross sections between singly ionized ions and the parent atoms were measured for dysprosium and cerium in the impact energy of 200-2000eV. The cross sections were determined from the ratio between the number of ions produced by charge transfer and those in primary ion beam. The primary ion beam was produced by a laser ion source in which their atoms were ionized by laser resonant photo-ionization. The slow ions produced by charge transfer and fast primary ions were detected with Faraday cups. The obtained cross sections were (1.82±0.14) x 10 -14 cm 2 for dysprosium and (0.88±0.12) x 10 -14 cm 2 for cerium in the above energy range. The difference of these values can mostly be explained by considering the electron configurations of these atoms and ions. (author)

  10. Multifractal detrended Cross Correlation Analysis of Foreign Exchange and SENSEX fluctuation in Indian perspective

    Science.gov (United States)

    Dutta, Srimonti; Ghosh, Dipak; Chatterjee, Sucharita

    2016-12-01

    The manuscript studies autocorrelation and cross correlation of SENSEX fluctuations and Forex Exchange Rate in respect to Indian scenario. Multifractal detrended fluctuation analysis (MFDFA) and multifractal detrended cross correlation analysis (MFDXA) were employed to study the correlation between the two series. It was observed that the two series are strongly cross correlated. The change of degree of cross correlation with time was studied and the results are interpreted qualitatively.

  11. Total Cross Section in $\\gamma\\gamma$ Collisions at LEP

    CERN Document Server

    Acciarri, M.; Adriani, O.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Ambrosi, G.; Anderhub, H.; Andreev, Valery P.; Angelescu, T.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, L.; Balandras, A.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Bhattacharya, S.; Biasini, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Buffini, A.; Buijs, A.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.M.; Casaus, J.; Castellini, G.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Cesaroni, F.; Chamizo, M.; Chang, Y.H.; Chaturvedi, U.K.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Civinini, C.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; Cotorobai, F.; de la Cruz, B.; Csilling, A.; Cucciarelli, S.; Dai, T.S.; van Dalen, J.A.; D'Alessandro, R.; de Asmundis, R.; Deglon, P.; Degre, A.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; van Dierendonck, D.; Dionisi, C.; Dittmar, M.; Dominguez, A.; Doria, A.; Dova, M.T.; Duchesneau, D.; Dufournaud, D.; Duinker, P.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Erne, F.C.; Ewers, A.; Extermann, P.; Fabre, M.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gau, S.S.; Gentile, S.; Gheordanescu, N.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; van Gulik, R.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hasan, A.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hidas, P.; Hirschfelder, J.; Hofer, H.; Holzner, G.; Hoorani, H.; Hou, S.R.; Hu, Y.; Iashvili, I.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Khan, R.A.; Kafer, D.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, D.; Kim, J.K.; Kirkby, Jasper; Kiss, D.; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Kopp, A.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Krenz, W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Lee, H.J.; Le Goff, J.M.; Leiste, R.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Lubelsmeyer, K.; Luci, C.; Luckey, David; Lugnier, L.; Luminari, L.; Lustermann, W.; Ma, W.G.; Maity, M.; Malgeri, L.; Malinin, A.; Mana, C.; Mangeol, D.; Mans, J.; Marian, G.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; von der Mey, M.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Moulik, T.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Niessen, T.; Nisati, A.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Oulianov, A.; Palomares, C.; Pandoulas, D.; Paoletti, S.; Paolucci, P.; Paramatti, R.; Park, H.K.; Park, I.H.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pieri, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Postema, H.; Pothier, J.; Prokofev, D.O.; Prokofiev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, M.A.; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Raven, G.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Rodin, J.; Roe, B.P.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, Stefan; Rosenbleck, C.; Roux, B.; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Sanders, M.P.; Schafer, C.; Schegelsky, V.; Schmidt-Kaerst, S.; Schmitz, D.; Schopper, H.; Schotanus, D.J.; Schwering, G.; Sciacca, C.; Seganti, A.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Siedenburg, T.; Son, D.; Smith, B.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stone, A.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Sztaricskai, T.; Tang, X.W.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Uchida, Y.; Ulbricht, J.; Valente, E.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobov, A.A.; Vorvolakos, A.; Wadhwa, M.; Wallraff, W.; Wang, M.; Wang, X.L.; Wang, Z.M.; Weber, A.; Weber, M.; Wienemann, P.; Wilkens, H.; Wu, S.X.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Ye, J.B.; Yeh, S.C.; Zalite, A.; Zalite, Yu.; Zhang, Z.P.; Zhu, G.Y.; Zhu, R.Y.; Zichichi, A.; Zilizi, G.; Zimmermann, B.; Zoller, M.

    2001-01-01

    The reaction e+e- -> e+e- gamma* gamma* -> e+e- hadrons for quasi-real photons is studied using data from root(s) = 183 GeV up to 202 GeV. Results on the total cross sections sigma(e+e- -> e+e- hadrons) and sigma(+e- gamma* gamma* -> e+e- hadrons) are given for the two-photon centre-of-mass energies 5 GeV < Wgammagamma < 185 GeV. The total cross section of two real photons is described by a Regge parametrisation. We observe a steeper rise with the two-photon centre-of-mass energy as compared to the hadron-hadron and the photon-proton cross sections. The data are also compared to the expectations of different theoretical models.

  12. A study on preparation of cross sectional anatomy specimen of cadaver

    International Nuclear Information System (INIS)

    Im, C. K.; Choi, B. I.; Park, J. H.; Chang, K. H.; Yeon, K. M.; Han, M. C.; Kim, C. W.

    1984-01-01

    With the advent of cross sectional image of CT, ultrasound and magnetic resonance, the need for knowledge of cross sectional anatomy is stranger than ever. To meet this need, preparation of cross sectional anatomy specimen using cadaver is indispensable, not only because it tis the real cut surface anatomy but also because overt limitations of radiographic image in both contrast and special resolution. Authors prepared cross sectional anatomy specimen using a male cadaver, comprising photographs and slides of the 60 cross cut slices from the head to the pelvis. After photography, each slices was embedded using transparent resin allowing permanent preservation of specimen without altering its original architecture. Author's unique method of preparation is presented and 4 representative specimens are illustrated comparing cadaver's CT image, cross cut surface photography, and photography of resin embedded slice of the same cut surface.

  13. Proton-Nucleus Elastic Cross Sections Using Two-Body In-Medium Scattering Amplitudes

    Science.gov (United States)

    Tripathi, R. K.; Wilson, John W.; Cucinotta, Francis A.

    2001-01-01

    Recently, a method was developed of extracting nucleon-nucleon (NN) cross sections in the medium directly from experiment. The in-medium NN cross sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the Langley Research Center. The ratio of the real to the imaginary part of the two-body scattering amplitude in the medium was investigated. These ratios are used in combination with the in-medium NN cross sections to calculate elastic proton-nucleus cross sections. The agreement is excellent with the available experimental data. These cross sections are needed for the radiation risk assessment of space missions.

  14. Behavior of cross flow heat exchangers during the cooling and dehumidification of air

    Energy Technology Data Exchange (ETDEWEB)

    Ober, C [Karlsruhe Univ. (TH) (Germany, F.R.). Inst. fuer Mess- und Regelungstechnik mit Maschinenlaboratorium

    1980-09-01

    The task of cross flow heat exchangers in room air engineering consists on the one hand in heating up the air and, on the other hand, in the simultaneous cooling and dehumidification. The facilities used for this purpose generally are multi-row finned pipe heat exchangers which when used for cooling contain cold water or brine as the working fluid. The use of directly evaporating freezing mixtures may not be included in this consideration. The model establishment for the dynamic and the static behavior of multi-row cross flow heat exchangers during cooling and dehumidification of air has been derived in this contribution. The representation is performed for the dynamic case in the complex, display range of the Laplace transformation. A comparison with experimental results can be done very simply by means of measurements of the frequency-responce curves in the form of Bode diagrams. The description of the static behaviour may be applied as a basis for humidity controls with more favourable energy utilization.

  15. Simplified polynomial representation of cross sections for reactor calculation

    International Nuclear Information System (INIS)

    Dias, A.M.; Sakai, M.

    1985-01-01

    It is shown a simplified representation of a cross section library generated by transport theory using the cell model of Wigner-Seitz for typical PWR fuel elements. The effect of burnup evolution through tables of reference cross sections and the effect of the variation of the reactor operation parameters considered by adjusted polynomials are presented. (M.C.K.) [pt

  16. Corporate Social Responsibility: A Cross Sectional Examination of Incentivization.

    Science.gov (United States)

    1995-09-01

    which address organizational behavior: Corporate Social Responsibility ( CSR ), Expense Preference Approach (EPA), Resource Dependency Theory (RDT...i V *>V CORPORATE SOCIAL RESPONSIBILITY : A CROSS SECTIONAL EXAMINATION OF INCENTIVIZATION THESIS Jennifer A. Block, B.S. First Lieutenant, USAF...Distribution/ Availability Codes Dist m Avail and/or Special \\&\\W 0\\1 CORPORATE SOCIAL RESPONSIBILITY : A CROSS SECTIONAL EXAMINATION OF

  17. A dissociative electron attachment cross-section estimator

    International Nuclear Information System (INIS)

    Munro, James J; Harrison, Stephen; Fujimoto, Milton M; Tennyson, Jonathan

    2012-01-01

    Dissociative electron attachment (DEA) is the major process where molecules are destroyed in low-energy plasmas. DEA cross sections are therefore important for a whole variety of applications but are both hard to measure or compute accurately. A method for estimating DEA cross sections based a simple resonance plus survival model is presented. Test results are presented for DEA of molecular oxygen and molecular chlorine, for which experimental measurements are available for comparison, and SiBr and SiBr 2 , for which no previous data is available. The estimator has been implemented as part of Quantemol-N expert system which uses the R-matrix method to predict resonance positions and widths.

  18. Covariance Evaluation Methodology for Neutron Cross Sections

    Energy Technology Data Exchange (ETDEWEB)

    Herman,M.; Arcilla, R.; Mattoon, C.M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.; Pritychenko, b.; Songzoni, A.A.

    2008-09-01

    We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.

  19. Consistent evaluation of neutron cross sections for the 242-244Cm isotopes

    International Nuclear Information System (INIS)

    Ignatyuk, A.V.; Maslov, V.M.

    1989-01-01

    The knowledge of neutron cross-sections for Curium isotopes is necessary for solving the problems of the external fuel cycle. Experimental information on the cross-sections is very meager and does not satisfy requirements and existing evaluations in different libraries differ substantially for fission and (n,2n) reaction cross-sections. This situation requires a critical review of the entire set of evaluations of the neutron cross-sections for Curium. 17 refs, 3 figs

  20. Technical notes. Rational approximations for cross-section space-shielding in doubly heterogeneous systems

    International Nuclear Information System (INIS)

    Stamatelatos, M.G.

    1976-01-01

    A simple yet accurate method of space-shielding cross sections in a doubly heterogeneous high-temperature gas-cooled reactor (HTGR) system using collision probabilities and rational approximations is presented. Unlike other more elaborate methods, this method does not require point-wise cross sections that are not explicitly generated in most popular cross-section codes. Consequently, this method makes double heterogeneity space-shielding possible for cross-section codes that do not proceed via point-wise cross sections and that usually allow only for single (fuel-rod) heterogeneity cross-section space-shielding. Results of calculations based on this method compare well with results of calculations based on more elaborate methods using point-wise cross sections. Moreover, the systematic trend of the difference between the results from this method and those from the more elaborate methods used for comparison supports the already existent opinion that the latter methods tend to overestimate the space-shielding cross-section correction in doubly heterogeneous HTGR systems

  1. Electron impact ionisation cross sections of iron oxides

    Science.gov (United States)

    Huber, Stefan E.; Mauracher, Andreas; Sukuba, Ivan; Urban, Jan; Maihom, Thana; Probst, Michael

    2017-12-01

    We report electron impact ionisation cross sections (EICSs) of iron oxide molecules, FexOx and FexOx+1 with x = 1, 2, 3, from the ionisation threshold to 10 keV, obtained with the Deutsch-Märk (DM) and binary-encounter-Bethe (BEB) methods. The maxima of the EICSs range from 3.10 to 9 . 96 × 10-16 cm2 located at 59-72 eV and 5.06 to 14.32 × 10-16 cm2 located at 85-108 eV for the DM and BEB approaches, respectively. The orbital and kinetic energies required for the BEB method are obtained by employing effective core potentials for the inner core electrons in the quantum chemical calculations. The BEB cross sections are 1.4-1.7 times larger than the DM cross sections which can be related to the decreasing population of the Fe 4s orbitals upon addition of oxygen atoms, together with the different methodological foundations of the two methods. Both the DM and BEB cross sections can be fitted excellently to a simple analytical expression used in modelling and simulation codes employed in the framework of nuclear fusion research. Supplementary material in the form of one pdf file available from the Journal web page at http://https://doi.org/10.1140/epjd/e2017-80308-2.

  2. Measurement of MA fission cross sections at YAYOI

    Energy Technology Data Exchange (ETDEWEB)

    Ohkawachi, Yasushi; Ohki, Shigeo; Wakabayashi, Toshio [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-03-01

    Fission cross section ratios of minor actinide nuclides (Am-241, Am-243) relative to U-235 in the fast neutron energy region have been measured using a back-to-back (BTB) fission chamber at YAYOI fast neutron source reactor. A small BTB fission chamber was developed to measure the fission cross section ratios in the center of the core at YAYOI reactor. Dependence of the fission cross section ratios on neutron spectra was investigated by changing the position of the detector in the reactor core. The measurement results were compared with the fission cross sections in the JENDL-3.2, ENDF/B-VI and JEF-2.2 libraries. It was found that calculated values of Am-241 using the JENDL-3.2, ENDF/B-VI and JEF-2.2 data are lower by about 15% than the measured value in the center of the core (the neutron average energy is 1.44E+6(eV)). And, good agreement can be seen the measured value and calculated value of Am-243 using the JENDL-3.2 data in the center of the core (the neutron average energy is 1.44E+6)(eV), but calculated values of Am-243 using the ENDF/B-VI and JEF-2.2 data are lower by 11% and 13% than the measured value. (author)

  3. Resonance charge exchange mechanism at high and moderate energies

    International Nuclear Information System (INIS)

    Bogdanov, A.V.; Gevorkyan, A.S.

    1984-01-01

    Charge exchange mechanisms at high and medium energies are investigated, ta king the resonance charge exchange of a proton by an hydrogen atom as an example . It is established that there are two classical charge exchange mechanisms rel ated to direct proton knockout from the bound state and one quantum-mechanical mechanism corresponding to the electron tunnelling from one bound state to anoth er. The classical cross-section diverges for two of these mechanisms, and the quasiclassical scattering amplitude must be calculated on the base of a complex classical trajectory. Physical grounds for the choice of such trajectories are discussed and calculations of the Van Vleck determinant for these mechanisms a re presented. Contributions from different mechanisms to the total charge excha nge cross-section are analyzed. A comparison with experimental data and results of other authors is made

  4. Curves and tables of neutron cross sections of fission product nuclei in JENDL-3

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Tsuneo [ed.

    1992-06-15

    Neutron cross sections of 172 nuclei in the fission product region stored in JENDL-3 are shown in graphs and tables. The evaluation work of these nuclei was made by the Fission Product Nuclear Data Working Group of the Japanese Nuclear Data Committee, in the neutron energy region from 10{sup {minus}5} eV to 20 MeV. Almost of the cross section data reproduced in graphs in this report. The cross section averaged over 38 energy intervals are listed in a table. Shown in order tables are thermal cross sections, resonance integrals, Maxwellian neutron flux average cross sections, fission spectrum average cross sections, 14-MeV cross sections, one group average cross sections in neutron flux of typical types of fission reactors and average cross sections in the 30-keV Maxwellian spectrum.

  5. Curves and tables of neutron cross sections of fission product nuclei in JENDL-3

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo

    1992-06-01

    Neutron cross sections of 172 nuclei in the fission product region stored in JENDL-3 are shown in graphs and tables. The evaluation work of these nuclei was made by the Fission Product Nuclear Data Working Group of the Japanese Nuclear Data Committee, in the neutron energy region from 10 -5 eV to 20 MeV. Almost all the cross section data are reproduced in graphs in this report. The cross section averaged over 38 energy intervals are listed in a table. Shown in other tables are thermal cross sections, resonance integrals, Maxwellian neutron flux average cross sections, fission spectrum average cross sections, 14-MeV cross sections, one group average cross sections in neutron flux of typical types of fission reactors and average cross sections in the 30-keV Maxwellian spectrum. (author)

  6. Porosity effects in the neutron total cross section of graphite

    International Nuclear Information System (INIS)

    Santisteban, J. R; Dawidowski, J; Petriw, S. N

    2009-01-01

    Graphite has been used in nuclear reactors since the birth of the nuclear industry due to its good performance as a neutron moderator material. Graphite is still an option as moderator for generation IV reactors due to its good mechanical and thermal properties at high operation temperatures. So, there has been renewed interest in a revision of the computer libraries used to describe the neutron cross section of graphite. For sub-thermal neutron energies, polycrystalline graphite shows a larger total cross section (between 4 and 8 barns) than predicted by existing theoretical models (0.2 barns). In order to investigate the origin of this discrepancy we measured the total cross section of graphite samples of three different origins, in the energy range from 0.001 eV to 10 eV. Different experimental arrangements and sample treatments were explored, to identify the effect of various experimental parameters on the total cross section measurement. The experiments showed that the increase in total cross section is due to neutrons scattered around the forward direction. We associate these small-angle scattered neutrons (SANS) to the porous structure of graphite, and formulate a very simple model to compute its contribution to the total cross section of the material. This results in an analytic expression that explicitly depends on the density and mean size of the pores, which can be easily incorporated in nuclear library codes. [es

  7. CFRMF spectrum update and application to dosimeter cross-section data testing

    International Nuclear Information System (INIS)

    Anderl, R.A.; Harker, Y.D.; Millsap, D.A.; Rogers, J.W.; Ryskamp, J.M.

    1982-01-01

    The Coupled Fast Reactivity Measurements Facility (CFRMF) at the Idaho National Engineering Laboratory (INEL) is a Cross Section Evaluation Working Group (CSEWG) benchmark for data testing of dosimetry, fission-product and actinide cross sections important to fast-reactor technology. In this paper we present the results of our work in updating the CFRMF spectrum characterization and in applying CFRMF integral data to testing ENDF/B-V dosimeter cross sections. Updated characterization of the central neutron spectrum includes the results of neutronics calculations with ENDF/B-V nuclear data, the generation of a fine-group spectrum representation for integral data-testing applications, and a sensitivity and uncertainty analysis which provides a flux-spectrum covariance matrix related to uncertainties and correlations in the nuclear data used in a neutronics calculation. Our application of CFRMF integral data to cross section testing has included both conventional integral testing analyses and least-squares-adjustment analyses with the FERRET code. The conventional integral data-testing analysis, based on C/E ratios, indicates discrepancies outside the estimated integral test uncertainty for the 6 Li(n,He), 10 B(n,He), 47 Ti(n,p), 58 Fe(n,γ), 197 Au(n,γ) and 232 Th(n,γ) cross sections. The integral test uncertainty included contributions from the measured integral data and from the spectrum and cross sections used to obtain the calculated integral data. Within the uncertainty and correlation specifications for the input spectrum and dosimeter cross sections, the least-squares-adjustment analysis indicated a high degree of consistency between the measured integral data and the ENDF/B-V dosimeter cross sections for all reactions except 10 B

  8. Progress on FP13 Total Cross Section Measurements Capability

    Energy Technology Data Exchange (ETDEWEB)

    Ullmann, John Leonard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Couture, Aaron Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Koehler, Paul E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mocko, Michal [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mosby, Shea Morgan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wender, Stephen Arthur [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-26

    An accurate knowledge of the neutron capture cross section is important for many applications. Experimental measurements are important since theoretical calculations of capture have been notoriously difficult, with the ratio of measured to calculated cross sections often a factor of 2 or more in the 10 keV to 1 MeV region. However, a direct measurement of capture cannot be made on many interesting radioactive nuclides because of their short half-life or backgrounds caused by their nuclear decay. On the other hand, neutron transmission measurements of the total cross section are feasible for a wide range of radioactive nuclides since the detectors are far from the sample, and often are less sensitive to decay radiation. The parameters extracted from a total cross section measurement, which include the average resonance spacing, the neutron strength function, and the average total radiation width, (Γγ), provide tight constraints on the calculation of the capture cross section, and when applied produce much more accurate results. These measurements can be made using the intense epithermal neutron flux at the Lujan Center on relatively small quantities of target material. It was the purpose of this project to investigate and develop the capability to make these measurements. A great deal of progress was made towards establishing this capability during 2016, including setting up the flight path and obtaining preliminary results, but more work remains to be done.

  9. Total cross section for chloroflouromethanes and CClx radicals by electron impact

    International Nuclear Information System (INIS)

    Gupta, Dhanoj; Antony, Bobby

    2013-01-01

    Highlights: ► A model to find total CS for freons and CCl x by e − impact is employed. ► Complex optical potential formalism is used to find total inelastic and elastic CS. ► Result shows very good agreement with previous data wherever available. ► Maiden attempt to find cross section for the CCl x radicals. -- Abstract: We report here the total cross section for chloroflouromethanes namely CCl 3 F (Freon 11), CCl 2 F 2 (Freon 12), CClF 3 (Freon 13), CCl 4 and CCl x (x = 1–3), radicals by electron impact 50 to 5000 eV. The total inelastic and elastic cross sections are obtained employing a complex optical potential formalism and solving the Schrödinger equation through partial wave analysis. The total cross section is obtained as the sum of total inelastic and elastic cross sections. The results obtained are compared with the existing experimental and theoretical data, wherever available. The present result shows reasonable agreement with previous data. For the CCl x radicals, we have predicted the total cross sections for the first time. The data reported here has immense interest to atmospheric and technological plasma modelling

  10. Cross section and linear polarization of tagged photons

    International Nuclear Information System (INIS)

    Asai, J.; Caplan, H.S.; Skopik, D.M.; DelBianco, W.; Maximon, L.C.

    1988-01-01

    Formulae for bremsstrahlung cross sections and polarizations are usually presented in coordinate systems not very suitable for application by experimental physicists to devices such as photon-tagging monochromators. In this paper the transformations between the different coordinate systems are presented, along with examples of the calculated cross sections and polarizations in a form convenient from the experimental standpoint. These examples also give the predicted characteristics of the photon tagger currently under construction at the Saskatchewan Accelerator Laboratory. (16 refs., 19 figs., tab.)

  11. Scattering cross-sections of common calibration gases measured by IBBCEAS technique

    Directory of Open Access Journals (Sweden)

    S.I. Issac

    Full Text Available In this study, incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS was used to measure scattering cross-sections of a few common gases in the 650–670 nm spectral range relative to that of dry air. Precise measurements of scattering cross-sections of these calibration gases in the visible spectral range are important. The IBBCEAS system developed in the laboratory was calibrated with a low-loss optical window. The measurements made at 660 nm were compared with previously measured cross-section values and found to be in good agreement with the existing measurements. Keywords: IBBCEAS, Rayleigh scattering, Scattering cross section

  12. Cross sectional moments and portfolio returns: Evidence for select emerging markets

    Directory of Open Access Journals (Sweden)

    Sanjay Sehgal

    2016-09-01

    Full Text Available Research does not indicate a consensus on the relationship between idiosyncratic volatility and asset returns. Moreover, the role of cross sectional higher order moments in predicting market returns is relatively unexplored. We show that the cross sectional volatility measure suggested by Garcia et al. is highly correlated with alternative measures of idiosyncratic volatility constructed as variance of errors from the capital asset pricing model and the Fama French model. We find that cross sectional moments help in predicting aggregate market returns in some sample countries and also provide information for portfolio formation, which is more consistent for portfolios sorted on sensitivity to cross sectional skewness.

  13. From ZZ to ZH : How Low Can These Cross Sections Go or Everybody, Let's Cross Section Limbo!

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Emanuel Alexandre [Stony Brook Univ., NY (United States)

    2009-08-01

    We report on two searches performed at the D0 detector at the Fermi National Laboratory. The first is a search for Z di-boson production with a theoretical cross section of 1.4 pb. The search was performed on 2.6 fb-1 of data and contributed to the first observation of ZZ production at a hadron collider. The second is a search for a low mass Standard Model Higgs in 4.2 fb-1 of data. The Higgs boson is produced in association with a Z boson where the Higgs decays hadronically and the Z decays to two leptons. The ZZ search was performed in both the di-electron and di-muon channels. For the ZH search, we will focus on the muonic decays where we expanded the traditional coverage by considering events in which one of the two muons fails the selection requirement, and is instead reconstructed as an isolated track. We consider Higgs masses between 100 and 150 GeV, with theoretical cross sections ranging from 0.17 to 0.042 pb, and set upper limits on the ZH production cross-section at 95% confidence level.

  14. Simple, empirical approach to predict neutron capture cross sections from nuclear masses

    Science.gov (United States)

    Couture, A.; Casten, R. F.; Cakirli, R. B.

    2017-12-01

    Background: Neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40 % , and has limited predictive power, with predictions from different models rapidly differing by an order of magnitude a few nucleons from the last measurement. Purpose: To develop a new approach to predicting neutron capture cross sections over broad ranges of nuclei that accounts for their values where known and which has reliable predictive power with small uncertainties for many nuclei where they are unknown. Methods: Experimental neutron capture cross sections were compared to empirical mass observables in regions of similar structure. Results: We present an extremely simple method, based solely on empirical mass observables, that correlates neutron capture cross sections in the critical energy range from a few keV to a couple hundred keV. We show that regional cross sections are compactly correlated in medium and heavy mass nuclei with the two-neutron separation energy. These correlations are easily amenable to predict unknown cross sections, often converting the usual extrapolations to more reliable interpolations. It almost always reproduces existing data to within 25 % and estimated uncertainties are below about 40 % up to 10 nucleons beyond known data. Conclusions: Neutron capture cross sections display a surprisingly strong connection to the two-neutron separation energy, a nuclear structure property. The simple, empirical correlations uncovered provide model-independent predictions of

  15. Cross sections of the lumped fission products for the AMZ library

    International Nuclear Information System (INIS)

    Ono, S.; Corcueca, R.P.; Nascimento, J.A.

    1985-01-01

    The preparation of the lumped fission product cross section for the AMZ library is described. For this purpose 100 nuclides were selected. The cross sections for each nuclide were generated by the NJOY code with evaluated nuclear data from ENDF/B-V, complemented with ENDF/B-IV data. A comparison is performed between the data obtained and the lumped fission product cross section of JFS-II [pt

  16. INTER, ENDF/B Thermal Cross-Sections, Resonance Integrals, G-Factors Calculation

    International Nuclear Information System (INIS)

    Dunford, Charles L.

    2007-01-01

    1 - Description of program or function: INTER calculates thermal cross sections, g-factors, resonance integrals, fission spectrum averaged cross sections and 14.0 MeV (or other energy) cross sections for major reactions in an ENDF-6 or ENDF-5 format data file. Version 7.01 (Jan 2005): set success flag after return from beginning. 2 - Method of solution: INTER performs integrations by using the trapezoidal rule

  17. Research on the Cross Section Precision of High-strength Steel Tube with Rectangular Section in Rotary Draw Bending

    Science.gov (United States)

    Yang, Hongliang; Zhao, Hao; Xing, Zhongwen

    2017-11-01

    For the demand of energy conservation and security improvement, high-strength steel (HSS) is increasingly being used to produce safety related automotive components. However, cross-section distortion occurs easily in bending of HSS tube with rectangular section (RS), affecting the forming precision. HSS BR1500HS tube by rotary draw bending is taken as the study object and a description method of cross-section distortion is proposed in this paper. The influence on cross-section precision of geometric parameters including cross-section position, thickness of tube, bend radius etc. are studied by experiment. Besides, simulation of the rotary draw bending of HSS tube with rectangular section by ABAQUS are carried out and compared to the experiment. The results by simulation agree well with the experiment and show that the cross-section is approximately trapezoidal after distortion; the maximum of distortion exists at 45 ∼ 60° of the bending direction; and the absolute and relative distortion values increase with the decreasing of tube thickness or bending radius. Therefore, the results can provide a reference for the design of geometric parameters of HSS tube with rectangular section in rotary draw bending.

  18. The evaluation of neutron total cross section for natural iron and aluminium

    International Nuclear Information System (INIS)

    Liu Shirui; Wang Chunhao; Zhao Defang

    1990-05-01

    The experimental data of total cross section were collected and evaluated for natural iron in the energy region from 1 keV to 20 MeV and for natural aluminium from 4.07 keV to 20 MeV. The evaluated data were recommended in the regions for them. The minimum values of Fe total cross section in the keV region were specially recommended. The resonance structures were briefly discussed for both Fe and Al. To make the evaluation better, all experimental measurements of neutron total cross section relative to Fe and Al were studied. Considering the resonance feature of medium weight nuclides, two criteria for selecting total cross section were presented: 1) the correlation between the precission of total cross section and neutron source; 2) the correlation between the accuracy of total cross section and the resolving power of the neutron spectrometer

  19. Analysis of K/sup -/K/sup +/ and. pi. /sup -/. pi. /sup +/ final states in 13 GeV K/sup -/p interactions. [Differential cross sections, density matrix elements, branching ratio

    Energy Technology Data Exchange (ETDEWEB)

    Brandenburg, G W; Carnegie, R K; Cashmore, R J; Davier, M; Lasinski, T A; Leith, D W.G.S.; Mathews, J A.J.; Walden, P; Williams, S H [Stanford Linear Accelerator Center, Calif. (USA)

    1976-03-01

    The differential cross sections and density matrix elements for the phi and rho/sup 0/ mesons have been measured in the reactions K/sup -/p..-->..K/sup -/K/sup +/(..lambda..,..sigma../sup 0/) and K/sup -/p..--> pi../sup -/..pi../sup +/(..lambda..,..sigma../sup 0/) at 13 GeV using a wire chamber spectrometer. The analysis shows that while the vector meson production is dominated by the natural parity exchange amplitude, some unnatural parity exchange is also required. Furthermore the phi and rho natural exchange cross sections are identical in shape and have the 2:1 relative strength expected in the quark model with K* and K** exchange degeneracy. The analysis of the clear peak-dip rho/sup 0/-..omega.. interference pattern observed in the ..pi../sup -/..pi../sup +/ data indicates that the ..omega.. production is in phase with the rho and of similar magnitude. Both the S* and f' meson are clearly observed in this experiment. The S* data are found to be consistent with S* parameters deduced from ..pi pi.. scattering analyses. The f' density matrix elements and a new limit on the f'..--> pi../sup -/..pi../sup +/ branching ratio are presented.

  20. Measurements of the electron and muon inclusive cross-sections

    Indian Academy of Sciences (India)

    We present the measurements of the differential cross-sections for inclusive electron and muon production in proton–proton collisions at a centre-of-mass energy of s = 7 TeV, using ∼ 1.4 pb-1 of data collected by the ATLAS detector at the Large Hadron Collider. The muon cross-section is measured as a function of muon ...

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