Measurement of the production cross-section of ψ → J/ψ ( o μ+ μ) π π in pp collisions at √s = 7 TeV at ATLAS

The prompt and non-prompt production cross-sections for ψ(2S) mesons are measured using 2.1 fb−1 of pp collision data at a centre-of-mass energy of 7TeV recorded by the ATLAS experiment at the LHC. The measurement exploits the ψ(2S) → J/ψ (→μ+μ−)π+π− decay mode, and probes ψ(2S) mesons with transverse momenta in the range10 ≤ pT < 100 GeV and rapidity |y| < 2.0. The results are compared to other measurements of ψ(2S) production at the LHC and to various theoretical models for prompt and non-prompt quarkonium production.

Measurement of the electroweak production of dijets in association with a Z-boson and distributions sensitive to vector boson fusion in proton-proton collisions at √s = 8 TeV using the ATLAS detector

Measurements of fiducial cross sections for the electroweak production of two jets in association with a Z-boson are presented. The measurements are performed using 20.3 fb−1 of proton-proton collision data collected at a centre-of-mass energy of p s = 8TeV by the ATLAS experiment at the Large Hadron Collider. The electroweak component is extracted by a fit to the dijet invariant mass distribution in a fiducial region chosen to enhance the electroweak contribution over the dominant background in which the jets are produced via the strong interaction. The electroweak cross sections measured in two fiducial regions are in good agreement with the Standard Model expectations and the background-only hypothesis is rejected with significance above the 5ơ level. The electroweak process includes the vector boson fusion production of a Z-boson and the data are used to place limits on anomalous triple gauge boson couplings. In addition, measurements of cross sections and differential distributions for inclusive Z-boson-plus-dijet production are performed in five fiducial regions, each with different sensitivity to the electroweak contribution. The results are corrected for detector effects and compared to predictions from the Sherpa and Powheg event generators.

Measurement of the inclusive isolated prompt photons cross section in pp collisions at s √ =7 TeV with the ATLAS detector using 4.6 fb −1

A measurement of the cross section for the production of isolated prompt photons in pp collisions at a center-of-mass energy s √ =7  TeV is presented. The results are based on an integrated luminosity of 4.6  fb −1 collected with the ATLAS detector at the LHC. The cross section is measured as a function of photon pseudorapidity η γ and transverse energy E γ T in the kinematic range 100≤E γ T <1000  GeV and in the regions |η γ |<1.37 and 1.52≤|η γ |<2.37 . The results are compared to leading-order parton-shower Monte Carlo models and next-to-leading-order perturbative QCD calculations. Next-to-leading-order perturbative QCD calculations agree well with the measured cross sections as a function of E γ T and η γ .

Measurement of the Inclusive Electron Neutrino Charged Current Cross Section on Carbon with the T2K Near Detector

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1  GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged νe charged current cross section on carbon is measured to be ⟨σ⟩ϕ=1.11±0.10(stat)±0.18(syst)×10−38  cm2/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10−38  cm2/nucleon and the GENIE prediction is 1.08×10−38  cm2/nucleon. The total νe charged current cross-section result is also in agreement with data from the Gargamelle experiment.

Measurement of the νμ charged current quasielastic cross section on carbon with the T2K on-axis neutrino beam

We report a measurement of the νµ charged current quasi-elastic cross-sections on carbon in the T2K on-axis neutrino beam. The measured charged current quasi-elastic cross-sections on carbon at mean neutrino energies of 1.94 GeV and 0.93 GeV are (11.95 ± 0.19(stat.) +1.82−1.47(syst.)) ×10^−39 cm^2/neutron, and (10.64 ± 0.37(stat.)+2.03−1.65(syst.)) × 10^−39 cm^2/neutron, respectively. These results agree well with the predictions of neutrino interaction models. In addition, we investigated the effects of the nuclear model and the multi-nucleon interaction.

Steps Ahead in the Few-Group CRoss-Section Library Generation at the Pin Level

There exists an interest in performing pin-by-pin calculations coupled with thermal hydraulics so as to improve the accuracy of nuclear reactor analysis. In the framework of the EU NURISP project, INRNE and UPM have generated an experimental version of a few group diffusion cross sections library with discontinuity factors intended for VVER analysis at the pin level with the COBAYA3 code. The transport code APOLLO2 was used to perform the branching calculations. As a first proof of principle the library was created for fresh fuel and covers almost the full parameter space of steady state and transient conditions. The main objective is to test the calculation schemes and post-processing procedures, including multi-pin branching calculations. Two library options are being studied: one based on linear table interpolation and another one using a functional fitting of the cross sections. The libraries generated with APOLLO2 have been tested with the pin-by-pin diffusion model in COBAYA3 including discontinuity factors; first comparing 2D results against the APOLLO2 reference solutions and afterwards using the libraries to compute a 3D assembly problem coupled with a simplified thermal-hydraulic model.

Análisis comparativo de procedimientos para la medición de las gemas y evaluación de su influencia en la determinación de las propiedades mecánicas de la madera de Pinus sylvestris L. de gran escuadría. Comparison of wanes measurement systems to evaluate their influence on the mechanical properties of large cross section timber of Pinus sylvestris L.

Las gemas se evalúan mediante la norma de clasificación visual (UNE 56544), pero su aplicación en estructuras existentes y grandes escuadrías resulta poco eficaz y conduce a estimaciones demasiado conservadoras. Este trabajo analiza la influencia de las gemas comparando la resistencia de piezas con gemas y piezas correctamente escuadradas. Se han analizado 218 piezas de pino silvestre con dimensiones nominales 150 x 200 x 4.200 mm, de las que 102 presentaban una gema completa a lo largo de toda su longitud y el resto estaban correctamente escuadradas. En las piezas con gema se ha medido la altura de la sección cada 30 cm (altura en cada cara y altura máxima). Para determinar la resistencia se han ensayado todas las piezas de acuerdo a la norma EN 408. Se ha comparado la resistencia obtenida para las piezas con gema, diferenciando si la gema se encuentra en el borde comprimido o en el borde traccionado, con las piezas escuadradas. Puede concluirse que la presencia de gemas disminuye la resistencia excepto si la gema se encuentra en el borde traccionado, en cuyo caso los resultados obtenidos han sido similares a los de las piezas escuadradas. The wanes on structural timber are evaluated according to the visual grading standard (UNE 56544), but its application on existing structures and large cross sections is ineffective and leads to conservative estimations. This paper analyzes the influence of the wanes by comparing the resistance of pieces with wanes and square pieces. 218 pieces of Scotch pine with nominal dimensions 150 x 200 x 4200 mm have been analyzed, 102 of them had a complete wane along its length and the rest were properly squared. The height of the cross section was measured every 30 cm (the height on each side and the maximum height) for the pieces with wane. The bending strength of all the pieces was obtained according to the EN 408 standard. The bending strength of the pieces with wane has been compared with the strength of the squared pieces, taking into account if the wane is positioned on the compressed edge or on the tensioned edge. It can be concluded that the bending strength of the pieces with wanes is lower than the one of squared pieces, except if the wanes are on the tensioned edge of the beam.

Review of the C-nat(n,gamma) cross section and criticality calculations of the graphite moderated reactor BR1

A review of the experimental data for natC(n,c) and 12C(n,c) was made to identify the origin of the natC capture cross sections included in evaluated data libraries and to clarify differences observed in neutronic calculations for graphite moderated reactors using different libraries. The performance of the JEFF-3.1.2 and ENDF/B-VII.1 libraries was verified by comparing results of criticality calculations with experimental results obtained for the BR1 reactor. This reactor is an air-cooled reactor with graphite as moderator and is located at the Belgian Nuclear Research Centre SCK-CEN in Mol (Belgium). The results of this study confirm conclusions drawn from neutronic calculations of the High Temperature Engineering Test Reactor (HTTR) in Japan. Furthermore, both BR1 and HTTR calculations support the capture cross section of 12C at thermal energy which is recommended by Firestone and Révay. Additional criticality calculations were carried out in order to illustrate that the natC thermal capture cross section is important for systems with a large amount of graphite. The present study shows that only the evaluation carried out for JENDL-4.0 reflects the current status of the experimental data.

A computer formulation for the analysis on continuous non prismatic folded plate structures of arbitrary cross-section

A computer solution to analyze nonprismatic folded plate structures is shown. Arbitrary cross-sections (simple and multiple), continuity over intermediate supports and general loading and longitudinal boundary conditions are dealt with. The folded plates are assumed to be straight and long (beam like structures) and some simplifications are introduced in order to reduce the computational effort. The formulation here presented may be very suitable to be used in the bridge deck analysis.

Optimization of multidimensional cross-section tables for few-group core calculations

Multigroup diffusion codes for three dimensional LWR core analysis use as input data pre-generated homogenized few group cross sections and discontinuity factors for certain combinations of state variables, such as temperatures or densities. The simplest way of compiling those data are tabulated libraries, where a grid covering the domain of state variables is defined and the homogenized cross sections are computed at the grid points. Then, during the core calculation, an interpolation algorithm is used to compute the cross sections from the table values. Since interpolation errors depend on the distance between the grid points, a determined refinement of the mesh is required to reach a target accuracy, which could lead to large data storage volume and a large number of lattice transport calculations. In this paper, a simple and effective procedure to optimize the distribution of grid points for tabulated libraries is presented. Optimality is considered in the sense of building a non-uniform point distribution with the minimum number of grid points for each state variable satisfying a given target accuracy in k-effective. The procedure consists of determining the sensitivity coefficients of k-effective to cross sections using perturbation theory; and estimating the interpolation errors committed with different mesh steps for each state variable. These results allow evaluating the influence of interpolation errors of each cross section on k-effective for any combination of state variables, and estimating the optimal distance between grid points.

Vortex-induced vibrations on bridges : the interaction mechanism in complex sections and a new proposed semi-empirical model

El presente trabajo de investigación se ocupa del estudio de las vibraciones verticales inducidas por vórtices (VIV) en aquellos puentes que, por sus características geométricas y propiedades dinámicas, muestran cierta sensibilidad este tipo de fenómeno aeroelástico. El objeto principal es el análisis del mecanismo de interacción viento-estructura sobre secciones no fuseladas de geometría simple, con objeto de realizar una adecuada caracterización del problema y poder abordar posteriormente el análisis de otras secciones de geometría más compleja, representativas de los principales elementos estructurales de los puentes, como arcos, tableros, torres y pilas. Este aspecto es fundamental durante la fase de diseño del puente, donde deberán tenerse en cuenta también una serie de detalles que pueden influir significativamente su sensibilidad ante problemas aerodinámicos, como la morfología y dimensiones principales de la sección transversal del tablero, la disposición de barreras de seguridad y barreras cortaviento, o las riostras que unen diferentes elementos estructurales. La configuración de dos elementos en tándem o la construcción de un puente en las inmediaciones de otro existente son otros aspectos a considerar respecto a la sensibilidad frente a efectos aeroelásticos. El estudio se ha llevado a cabo principalmente mediante la implementación de simulaciones numéricas que reproducen la interacción entre la corriente de aire y secciones representativas de modelos estructurales, a partir de un código CFD basado en el método de las partículas de vórtices (VPM), siguiendo por tanto un esquema Lagrangiano. Los resultados han sido validados con datos experimentales existentes, valores procedentes de ensayos en túnel de viento y registros reales a partir de diferentes casos de estudio: Alconétar (2006), Niterói (1980), Trans- Tokyo Bay (1995) y Volgogrado (2010). Finalmente, se propone un modelo semi-empírico para la estimación del rango de velocidades críticas y amplitudes de oscilación basado en la utilización de las derivadas de flameo de Scanlan, y la densidad espectral de las fuerzas aerodinámicas en el dominio de la frecuencia. The present research work concerns the study of vertical vortex-induced vibrations (VIV) in bridges which show certain sensitivity to this type of aeroelastic phenomenon. It focuses on the analysis of the wind-structure interaction mechanism on bluff sections, with the objective of making a good characterisation of the problem and subsequently addressing the analysis of sections with a complex geometry, which are representative of the bridge structural elements, such as arches, decks, towers and piers. This issue is of relative importance during the bridge design phase, since minor details of the aforementioned elements can significantly influence its sensitivity to aerodynamic problems. The shape and main dimensions of the deck cross section, the addition of safety barriers and windshields, the presence of braces to enhance the structure mechanical properties, the utilisation of cross sections in tandem arrangement, or the erection of a new bridge in the vicinity of another existing one are some of the aspects to be considered regarding the sensitivity to the aeroelastic effects. The study has been carried out mainly through the implementation of numerical simulations that reproduces the interaction between the airflow and the representative cross section of a structural bridge model, by the use of a CFD code based on the vortex particle method (VPM), thus following a Lagrangian scheme. The results have been validated with existing experimental data, values from wind tunnel tests and full scale observations from the different case studies: Alconétar (2006), Niterói (1980), Trans-Tokyo Bay (1995) and Volgograd (2010). Finally, a new semi-empirical model is proposed for the estimation of the critical wind velocity ranges and oscillation amplitudes based on the use of the Scanlan’s flutter derivatives and the power spectral density of aerodynamic force time history in the frequency domain.

Measurement of the muon neutrino inclusive charged-current cross section in the energy range of 1–3 GeV with the T2K INGRID detector

We report a measurement of the νµ-nucleus inclusive charged current cross section (=σ cc) on ironusing data from exposed to the J-PARC neutrino beam. The detector consists of 14 modules in total, which are spread over a range of off-axis angles from 0◦ to 1.1◦. The variation in the neutrino energy spectrum as a function of the off-axis angle, combined with event topology information, is used to calculate this cross section as a function of neutrino energy. The cross section is measured to be σcc(1.1 GeV) = 1.10±0.15 (10^−38cm^2/nucleon), σcc(2.0 GeV) = 2.07±0.27 (10^−38cm^2/nucleon), and σcc(3.3 GeV) = 2.29 ± 0.45 (10^−38cm^2/nucleon), at energies of 1.1, 2.0, and 3.3 GeV, respectively. These results are consistent with the cross section calculated by the neutrino interaction generators currently used by T2K. More importantly, the method described here opens up a new way to determine the energy dependence of neutrino-nucleus cross sections.

Safety aspects of roadside cross-section design. Final report.

Federal Highway Administration, Office of Research and Development, Washington, D.C.

Conference on Neutron Cross Section Technology : proceedings /

Later conferences issued under title: Conference on Neutron Cross Sections and Technology.

Bibliography of low energy electron and photon cross section data (through December 1974) /

Includes index.