Diagnosis of power generator sets by analyzing the crank shaft angular speed
This thesis deals with the diagnosis of a powerful 20-cylinder diesel engine which runs a generator set in a nuclear plant. The objective is to make a diagnosis by analyzing the crank shaft angular speed variations. Only combustion related faults are investigated. As the engine is very large, the first crank shaft natural modes are in the low frequencies. Torsional vibrations of the flexible crank shaft strongly complicate the analysis of the angular speed variations. Little attention has been paid to such large engines in the literature. First, a dynamical model with the assumption of a flexible crank shaft is established. The parameters of the model are optimized with the help of actual data. Then, an original automated diagnosis based on pattern recognition of the angular speed waveforms is proposed. Indeed, any faulty cylinder in combustion stroke will distort the angular speed waveform in a specific way which depends on its location with respect to nodes and anti-nodes of the modes. Reference patterns, representative of the engine conditions, are computed with the model constituting the main originality of this work. Promising results are obtained in operational phase. An experimental fuel leakage fault was correctly diagnosed, including detection and localization of the faulty cylinder and an indication of the severity of the fault. (author)
Measurements of pp spin correlation coefficients Axx, Ayy, and Axz and analyzing power Ay for pp elastic scattering at 197.4 MeV over the laboratory angular range 3.5 degree - 43.5 degree (θc.m.=7 degree - 90 degree) have been carried out. The typical statistical accuracy per 1 degree angle bin is better than 0.02 for the Amn and better than 0.005 for Ay. Systematic errors are negligible except for an overall normalization uncertainty of 2.5% for Amn and 1.3% for Ay. The experiment makes use of a polarized hydrogen gas target internal to a proton storage ring (IUCF Cooler) and a circulating beam of polarized protons. The target polarization is switched in sign and direction (x,y,z) every 2 s by reversing a weak guide field (∼0.3 mT). Scattered and recoil protons are detected in coincidence by two sets of wire chambers, by scintillators, and by silicon-strip recoil detectors placed 5 cm from the proton beam. Analysis methods and comparison to recent pp partial-wave analyses and NN potential models are described. copyright 1998 The American Physical Society
Electro-optic analyzer of angular momentum hyperentanglement.
Wu, Ziwen; Chen, Lixiang
2016-01-01
Characterizing a high-dimensional entanglement is fundamental in quantum information applications. Here, we propose a theoretical scheme to analyze and characterize the angular momentum hyperentanglement that two photons are entangled simultaneously in spin and orbital angular momentum. Based on the electro-optic sampling with a proposed hyper-entanglement analyzer and the simple matrix operation using Cramer rule, our simulations show that it is possible to retrieve effectively both the information about the degree of polarization entanglement and the spiral spectrum of high-dimensional orbital angular momentum entanglement. PMID:26911530
Noise and analyzer-crystal angular position analysis for analyzer-based phase-contrast imaging
The analyzer-based phase-contrast x-ray imaging (ABI) method is emerging as a potential alternative to conventional radiography. Like many of the modern imaging techniques, ABI is a computed imaging method (meaning that images are calculated from raw data). ABI can simultaneously generate a number of planar parametric images containing information about absorption, refraction, and scattering properties of an object. These images are estimated from raw data acquired by measuring (sampling) the angular intensity profile of the x-ray beam passed through the object at different angular positions of the analyzer crystal. The noise in the estimated ABI parametric images depends upon imaging conditions like the source intensity (flux), measurements angular positions, object properties, and the estimation method. In this paper, we use the Cramér–Rao lower bound (CRLB) to quantify the noise properties in parametric images and to investigate the effect of source intensity, different analyzer-crystal angular positions and object properties on this bound, assuming a fixed radiation dose delivered to an object. The CRLB is the minimum bound for the variance of an unbiased estimator and defines the best noise performance that one can obtain regardless of which estimation method is used to estimate ABI parametric images. The main result of this paper is that the variance (hence the noise) in parametric images is directly proportional to the source intensity and only a limited number of analyzer-crystal angular measurements (eleven for uniform and three for optimal non-uniform) are required to get the best parametric images. The following angular measurements only spread the total dose to the measurements without improving or worsening CRLB, but the added measurements may improve parametric images by reducing estimation bias. Next, using CRLB we evaluate the multiple-image radiography, diffraction enhanced imaging and scatter diffraction enhanced imaging estimation techniques
Loviisa nuclear power plant analyzer
The APROS Simulation Environment has been developed since 1986 by Imatran Voima Oy (IVO) and the Technical Research Centre of Finland (VTT). It provides tools, solution algorithms and process components for use in different simulation systems for design, analysis and training purposes. One of its main nuclear applications is the Loviisa Nuclear Power Plant Analyzer (LPA). The Loviisa Plant Analyzer includes all the important plant components both in the primary and in the secondary circuits. In addition, all the main control systems, the protection system and the high voltage electrical systems are included. (orig.)
Zhou, Hailong; Dong, Jianji; Zhang, Pei; Chen, Dongxu; Cai, Xinlun; Li, Fuli; Zhang, Xinliang
2016-01-01
The function to measure orbital angular momentum (OAM) distribution of vortex light is essential for OAM applications. Although there are lots of works to measure OAM modes, it is difficult to measure the power distribution of different OAM modes quantitatively and instantaneously, let alone measure the phase distribution among them. In this work, we demonstrate an OAM complex spectrum analyzer, which enables to measure the power and phase distribution of OAM modes simultaneously by employing rotational Doppler Effect. The original OAM mode distribution is mapped to electrical spectrum of beating signals with a photodetector. The power distribution and phase distribution of superimposed OAM beams are successfully retrieved by analyzing the electrical spectrum. We also extend the measurement to other spatial modes, such as linear polarization modes. These results represent a new landmark of spatial mode analysis and show great potentials in optical communication and OAM quantum state tomography.
BB mode angular power spectrum of CMB from massive gravity
Malsawmtluangi, N
2016-01-01
The primordial massive gravitational waves are placed in the squeezed vacuum state and corresponding $BB$-mode correlation angular power spectrum of the cosmic microwave background is obtained for various slow roll inflation models. The angular power spectrum is compared with the limit of BICEP2/Keck and Planck joint analysis data and the hybrid inflation model is found favorable.
DELTA - a computer program to analyze gamma-gamma angular correlations from unaligned states
A computer program to analyze gamma-gamma angular correlations from radioactive decay and from thermal-neutron capture is described. The program can, in addition to correlation data, handle mixing ratio and conversion coefficient data. (author)
Two-color ghost imaging with enhanced angular resolving power
This article reports an experimental demonstration on nondegenerate, two-color, biphoton ghost imaging which reproduced a ghost image with enhanced angular resolving power by means of a greater field of view compared with that of classical imaging. With the same imaging magnification, the enhanced angular resolving power and field of view compared with those of classical imaging are 1.25:1 and 1.16:1, respectively. The enhancement of angular resolving power depends on the ratio between the idler and the signal photon frequencies, and the enhancement of the field of view depends mainly on the same ratio and also on the distances of the object plane and the imaging lens from the two-photon source. This article also reports the possibility of reproducing a ghost image with the enhancement of the angular resolving power by means of a greater imaging amplification compared with that of classical imaging.
Noise and Analyzer-Crystal Angular Position Analysis for Analyzer-Based Phase-Contrast Imaging
Majidi, Keivan; Li, Jun; Muehleman, Carol; Brankov, Jovan G.
2014-01-01
The analyzer-based phase-contrast X-ray imaging (ABI) method is emerging as a potential alternative to conventional radiography. Like many of the modern imaging techniques, ABI is a computed imaging method (meaning that images are calculated from raw data). ABI can simultaneously generate a number of planar parametric images containing information about absorption, refraction, and scattering properties of an object. These images are estimated from raw data acquired by measuring (sampling) the...
Templates for the Sunyaev-Zel'dovich Angular Power Spectrum
Trac, Hy; Ostriker, Jeremiah P
2010-01-01
We present templates for the Sunyaev-Zel'dovich (SZ) angular power spectrum based on four models for the nonlinear gas distribution. The frequency-dependent SZ temperature fluctuations, with thermal (TSZ) and kinetic (KSZ) contributions, are calculated by tracing through a dark matter simulation, processed to include gas in dark matter halos and in the filamentary intergalactic medium. Different halo gas models are compared to study how star formation, energetic feedback, and nonthermal pressure support influence the angular power spectrum. The standard model has been calibrated to reproduce the stellar and gas fractions and X-ray scaling relations measured from low redshift clusters and groups. The other models illustrate the current theoretical and empirical uncertainties relating to properties of the intracluster medium. Relative to the standard model, their angular power spectra differ by approximately 50% (TSZ), 20% (KSZ), and 40% (SZ at 148 GHz) for l=3000, sigma_8=0.8, and homogeneous reionization at z...
Estimating the angular power spectrum of z > 2 BOSS QSOs using the MASTER method
Maldonado, Felipe; Huffenberger, Kevin; Rotti, Aditya
2016-01-01
We implement the MASTER method for angular power spectrum estimation and apply it to z > 2 quasars selected by the SDSS-III BOSS survey. Quasars are filtered for completeness and bad spectra, and include ~100,000 QSOs in the CORE sample and ~75,000 in the non-uniform BONUS sample. We estimate the angular power spectrum in redshift shells to constrain the matter power spectrum and quasar properties. In the future, we will jointly analyze overlapping Cosmic Microwave Background lensing maps from the Atacama Cosmology Telescope to place further constraints.
Impact of Wind Power on the Angular Stability of a Power System
Djemai NAIMI; Bouktir, Tarek
2008-01-01
Wind energy conversion systems are very different in nature from conventional generators. Therefore dynamic studies must be addressed in order to integrate wind power into the power system. Angular stability assessment of wind power generator is one of main issues in power system security and operation. The angular stability for the wind power generator is determined by its corresponding Critical Clearing Time (CCT). In this paper, the effect of wind power on the transient fault behavior is i...
A Three-Dimensional Angular Scattering Response Including Path Powers
Mammasis, Kostantinos; Santi, Paolo; Goulianos, Angelos
2011-01-01
In this paper the angular power spectrum exhibited under a three-dimensional (3-D) Gaussian scatter distribution at fixed observation points in space is investigated. Typically, these correspond to the mobile and base units respectively. Unlike other spatial channel models, the derived model accounts for the distance to each scatterer from the observation point and transforms distances into power values under the assumption of free-space propagation. The proposed 3-D spatial channel model fol...
Reconstructing the galaxy redshift distribution from angular cross power spectra
Sun, L; Tao, C
2015-01-01
The control of photometric redshift (photo-$z$) errors is a crucial and challenging task for precision weak lensing cosmology. The spacial cross-correlations (equivalently, the angular cross power spectra) of galaxies between tomographic photo-$z$ bins are sensitive to the true redshift distribution $n_i(z)$ of each bin and hence can help calibrate the photo-$z$ error distribution for weak lensing surveys. Using Fisher matrix analysis, we investigate the contributions of various components of the angular power spectra to the constraints of $n_i(z)$ parameters and demonstrate the importance of the cross power spectra therein, especially when catastrophic photo-$z$ errors are present. We further study the feasibility of reconstructing $n_i(z)$ from galaxy angular power spectra using Markov Chain Monte Carlo estimation. Considering an LSST-like survey with $10$ photo-$z$ bins, we find that the underlying redshift distribution can be determined with a fractional precision ($\\sigma(\\theta)/\\theta$ for parameter $\\...
Moshkelgosha V.
2012-06-01
Full Text Available Statement of Problem: Evaluation of diagnostic records as a supplement to direct examination has an important role in treatment planning of orthodontic patients with aesthetic needs. Photogrammetry as a quantitative tool has recently attracted the attention of researchers again.Purpose: The purpose of this study was to design computer software to analyze orthodontic patients’ facial profile photographic images and to estimate reliability and validity of its measurement.Materials and Method: Profile photographic images of 20 volunteered students were taken in the natural head position with standard technique. Manual linear and angular measurements were used as a gold standard and compared with the results obtained from Aesthetic analyzer Software (designed for that purpose. Dahlberg’s method error and Intraclass Correlation Coefficient (ICC was used to estimate validity, reliability and inter-examiner errors.Results: Almost all the measurements showed a high correlation between the manual and computerized method (ICC>0.75. The maximum method errors computed from Dahlberg’s formula were 1.345 mm in linear and 3.294 degrees in angular measurements. At the highest levels, inter-examiner errors were 1.684 mm and 3.741 degrees in linear and angular measurements, respectively. Conclusion: Although a low budget has been allocated for the design of Aesthetic Analyzer software, its features are comparable with commercially available products. The software’s capabilities can be increased. The results of the current study indicated that the software is accurate and repeatable in photographic analysis of orthodontic patients.
Angular Power Spectrum in Modular Invariant Inflation Model
Hayashi, M J; Takami, T; Okame, Y; Takagi, K; Watanabe, T; Hayashi, Mitsuo J.; Hirai, Shiro; Takami, Tomoyuki; Okame, Yusuke; Takagi, Kenji; Watanabe, Tomoki
2006-01-01
We propose a scalar potential of inflation, motivated by the modular invariant supergravity and computed the angular power spectra of the adiabatic density perturbations. The potential consists of three scalar fields S, Y and T with the two free parameters. By fitting the parameters with the cosmological data at the fixed point T=1, we find the potential behaves as that of the single field S, which slowly rolls down along the minimized trajectory in Y and gives rise the sufficient inflation matching with the recent three-year WMAP data, e.g. the spectral index n_s = 0.951. The TT and TE angular power spectra obtained from our model almost completely coincides with the fitting of the LambdaCDM model. We conclude that our model is considered to be an adequate theory of inflation to explain the present data, although more theoritical foundation of the model should be required.
Angular Power Spectrum in Modular Invariant Inflation Model
A scalar potential of inflation is proposed and the angular power spectra of the adiabatic density perturbations are computed. The potential consists of three scalar fields, S, Y and T, together with two free parameters. By fitting the parameters to cosmological data at the fixed point T = 1, we find that the potential behaves like the single-field potential of S, which slowly rolls down. We further show that the inflation predictions corresponding to this potential provide a good fit to the recent three-year WMAP data, e.g. the spectral index ns = 0.951.The TT and TE angular power spectra obtained from our model almost completely coincide with the corresponding results obtained from the ΛCDM model. We conclude that our model is considered to be an adequate theory of inflation that explains the present data
Adaptive power-controllable orbital angular momentum (OAM) multicasting
Li, Shuhui; Wang, Jian
2015-01-01
We report feedback-assisted adaptive multicasting from a single Gaussian mode to multiple orbital angular momentum (OAM) modes using a single phase-only spatial light modulator loaded with a complex phase pattern. By designing and optimizing the complex phase pattern through the adaptive correction of feedback coefficients, the power of each multicast OAM channel can be arbitrarily controlled. We experimentally demonstrate power-controllable multicasting from a single Gaussian mode to two and six OAM modes with different target power distributions. Equalized power multicasting, “up-down” power multicasting and “ladder” power multicasting are realized in the experiment. The difference between measured power distributions and target power distributions is assessed to be less than 1 dB. Moreover, we demonstrate data-carrying OAM multicasting by employing orthogonal frequency-division multiplexing 64-ary quadrature amplitude modulation (OFDM 64-QAM) signal. The measured bit-error rate curves and observed optical signal-to-noise ratio penalties show favorable operation performance of the proposed adaptive power-controllable OAM multicasting. PMID:25989251
Adaptive power-controllable orbital angular momentum (OAM) multicasting.
Li, Shuhui; Wang, Jian
2015-01-01
We report feedback-assisted adaptive multicasting from a single Gaussian mode to multiple orbital angular momentum (OAM) modes using a single phase-only spatial light modulator loaded with a complex phase pattern. By designing and optimizing the complex phase pattern through the adaptive correction of feedback coefficients, the power of each multicast OAM channel can be arbitrarily controlled. We experimentally demonstrate power-controllable multicasting from a single Gaussian mode to two and six OAM modes with different target power distributions. Equalized power multicasting, "up-down" power multicasting and "ladder" power multicasting are realized in the experiment. The difference between measured power distributions and target power distributions is assessed to be less than 1 dB. Moreover, we demonstrate data-carrying OAM multicasting by employing orthogonal frequency-division multiplexing 64-ary quadrature amplitude modulation (OFDM 64-QAM) signal. The measured bit-error rate curves and observed optical signal-to-noise ratio penalties show favorable operation performance of the proposed adaptive power-controllable OAM multicasting. PMID:25989251
Analyzing angular distributions for two-step dissociation mechanisms in velocity map imaging.
Straus, Daniel B; Butler, Lynne M; Alligood, Bridget W; Butler, Laurie J
2013-08-15
Increasingly, velocity map imaging is becoming the method of choice to study photoinduced molecular dissociation processes. This paper introduces an algorithm to analyze the measured net speed, P(vnet), and angular, β(vnet), distributions of the products from a two-step dissociation mechanism, where the first step but not the second is induced by absorption of linearly polarized laser light. Typically, this might be the photodissociation of a C-X bond (X = halogen or other atom) to produce an atom and a momentum-matched radical that has enough internal energy to subsequently dissociate (without the absorption of an additional photon). It is this second step, the dissociation of the unstable radicals, that one wishes to study, but the measured net velocity of the final products is the vector sum of the velocity imparted to the radical in the primary photodissociation (which is determined by taking data on the momentum-matched atomic cophotofragment) and the additional velocity vector imparted in the subsequent dissociation of the unstable radical. The algorithm allows one to determine, from the forward-convolution fitting of the net velocity distribution, the distribution of velocity vectors imparted in the second step of the mechanism. One can thus deduce the secondary velocity distribution, characterized by a speed distribution P(v1,2°) and an angular distribution I(θ2°), where θ2° is the angle between the dissociating radical's velocity vector and the additional velocity vector imparted to the product detected from the subsequent dissociation of the radical. PMID:23464815
Impact of Wind Power on the Angular Stability of a Power System
Djemai NAIMI
2008-06-01
Full Text Available Wind energy conversion systems are very different in nature from conventional generators. Therefore dynamic studies must be addressed in order to integrate wind power into the power system. Angular stability assessment of wind power generator is one of main issues in power system security and operation. The angular stability for the wind power generator is determined by its corresponding Critical Clearing Time (CCT. In this paper, the effect of wind power on the transient fault behavior is investigated by replacing the power generated by two main types of wind turbine, increasing gradually a rate of wind power penetration and changing the location of wind resources. The simulation analysis was established on a 14 bus IEEE test system by PSAT/Matlab, which gives access to an extensive library of grid components, and relevant wind turbine model.
Pulsed power for angular multiplexed laser fusion drivers
The feasibility of using rare gas-halide lasers, in particular the KrF laser, as inertial confinement fusion (ICF) drivers has been assessed. These lasers are scalable to the required high energy (approx. =1-5 MJ) in a short pulse (approx. =10 ns) by optical angular multiplexing, and integration of the output from approx. =100 kJ laser amplifier subsystems. The e-beam current density (approx. =50A/cm2) and voltage (approx. =800 kV) required for these power amplifiers lead to an e-beam impedance of approx. =0.2Ω for approx. =300 ns pump time. This impedance level requires modularization of the large area e-gun, a) to achieve a diode inductance consistent with fast current risetime, b) to circumvent dielectric breakdown constraints in the pulse forming lines, and c) to reduce the requirement for guide magnetic fields. Pulsed power systems requirements, design concepts, scalability, tradeoffs, and performance projections are discussed in this paper
The Angular Power Spectra of Photometric SDSS LRGs
Thomas, Shaun A; Lahav, Ofer
2010-01-01
We construct new galaxy angular power spectra based on the extended, updated and final SDSS II Luminous Red Galaxy (LRG) photometric redshift survey: MegaZ DR7. Encapsulating 7746 deg^{2} we utilise 723,556 photometrically determined LRGs between 0.45 < z < 0.65 in a 3.3 (Gpc h^{-1})^3 spherical harmonic analysis of the galaxy distribution. By combining four photometric redshift bins we find preliminary parameter constraints of f_{b} = \\Omega_{b}/\\Omega_{m} = 0.173 +/- 0.046 and \\Omega_{m} = 0.260 +/- 0.035 assuming H_{0} = 75 km s^{-1} Mpc^{-1}, n_{s}=1 and \\Omega_{k} = 0. These limits are consistent with the CMB and the previous data release (DR4). The C_{\\ell} are sensitive to redshift space distortions and therefore we also recast our constraints into a measurement of \\beta ~ \\Omega_{m}^{0.55}/b in different redshift shells. The robustness of these power spectra with respect to a number of potential systematics such as extinction, photometric redshift and ANNz training set extrapolation are examined...
Constraints on massive neutrinos from the CFHTLS angular power spectrum
Xia, Jun-Qing [Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, I-34136 Trieste (Italy); Granett, Benjamin R.; Guzzo, Luigi [INAF — Osservatorio Astronomico di Brera, Via E. Bianchi 46, 23807 Brera (Italy); Viel, Matteo [INAF — Osservatorio Astronomico di Trieste, Via G.B. Tiepolo 11, I-34131 Trieste (Italy); Bird, Simeon [School of Natural Sciences, Institute for Advanced Study, Princeton, NJ 08540 (United States); Haehnelt, Martin G. [Institute of Astronomy and Kavli Institute for Cosmology, Madingley Road, CB3 0HA, Cambridge (United Kingdom); Coupon, Jean [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); McCracken, Henry Joy; Mellier, Yannick, E-mail: xia@sissa.it, E-mail: ben.granett@brera.inaf.it, E-mail: viel@oats.inaf.it, E-mail: spb@ias.edu, E-mail: luigi.guzzo@brera.inaf.it, E-mail: haehnelt@ast.cam.ac.uk, E-mail: coupon@asiaa.sinica.edu.tw, E-mail: hjmcc@iap.fr, E-mail: mellier@iap.fr [Institut d' Astrophysique de Paris, UMR 7095 CNRS, Universitè Pierre et Marie Curie, 98 bis Boulevard Arago, 75014 Paris (France)
2012-06-01
We use the galaxy angular power spectrum at z ∼ 0.5–1.2 from the Canada-France-Hawaii-Telescope Legacy Survey Wide fields (CFHTLS-Wide) to constrain separately the total neutrino mass Σm{sub ν} and the effective number of neutrino species N{sub eff}. This survey has recently benefited from an accurate calibration of the redshift distribution, allowing new measurements of the (non-linear) matter power spectrum in a unique range of scales and redshifts sensitive to neutrino free streaming. Our analysis makes use of a recent model for the effect of neutrinos on the weakly non-linear matter power spectrum derived from accurate N-body simulations. We show that CFHTLS, combined with WMAP7 and a prior on the Hubble constant provides an upper limit of Σm{sub ν} < 0.29 eV and N{sub eff} = 4.17{sup +1.62}{sub −1.26} (2 σ confidence levels). If we omit smaller scales which may be affected by non-linearities, these constraints become Σm{sub ν} < 0.41 eV and N{sub eff} = 3.98{sup +2.02}{sub −1.20} (2 σ confidence levels). Finally we show that the addition of other large scale structures probes can further improve these constraints, demonstrating that high redshift large volumes surveys such as CFHTLS are complementary to other cosmological probes of the neutrino mass.
Analyzing-power measurements for the 3He(t,d)4He reaction
We report analyzing-power angular distributions for the 3He(t,d)4He reaction at bombarding energies of 9.02, 12.86, and 17.02 MeV, and an excitation function at 900 c.m. from 9.02 to 17.27 MeV. The angular distributions show marked deviations from the antisymmetric shape predicted by a simple particle-transfer model incorporating charge symmetry. Reaction mechanisms and violations of charge symmetry which might account for the data are discussed
A Remark on the Estimation of Angular Power Spectra in the Presence of Foregrounds
White, M
1998-01-01
It is common practice to estimate the errors on the angular power spectrum which could be obtained by an experiment with a given angular resolution and noise level. Several authors have also addressed the question of foreground subtraction using multi-frequency observations. In such observations the angular resolution of the different frequency channels is rarely the same. In this report we point out how the ``effective'' beam size and noise level change with ell in this case, and give an expression for the error on the angular power spectrum as a function of ell.
Analytical model for CMB temperature angular power spectrum from cosmic (super-)strings
Yamauchi, Daisuke; Takahashi, Keitaro; Sendouda, Yuuiti; Yoo, Chul-Moon; Sasaki, Misao
2010-01-01
We present a new analytical method to calculate the small angle CMB temperature angular power spectrum due to cosmic (super-)string segments. In particular, using our method, we clarify the dependence on the intercommuting probability $P$. We find that the power spectrum is dominated by Poisson-distributed string segments. The power spectrum for a general value of $P$ has a plateau on large angular scales and shows a power-law decrease on small angular scales. The resulting spectrum in the ca...
In order to improve existing I=0 phase shift solutions, the spin correlation parameter, ANN, and the analyzing powers, A0N and AN0, have been measured in n-p elastic scattering over an angular range of 50 degrees -150 degrees (c.m.) at three neutron energies, 220, 325 and 425 MeV to an absolute accuracy of ±0.03. The data have a profound effect on various phase parameters, particularly the 1P1, 3D2 and ε1 phase parameters which in some cases change by almost a degree. With exception of the highest energy, the data support the predictions of the latest version of the Bonn potential. Also the analyzing power data (A0N and AN0) measured at 477 MeV in a different experiment over a limited angular range (60 degrees - 80 degrees (c.m.)) are reported here. (Author) 30 refs., 10 figs., 5 tabs
Morioka, Y.; Tomiyama, K.; Arima, H. (Kansai Electric Power Co., Inc., Osaka (Japan)); Sawai, K.; Omata, K.; Matsushima, T.; Takagi, K.; Ishibashi, A.; Saito, H. (Toshiba Corp., Tokyo (Japan))
1993-07-01
The purpose of this newly developed equipment is to separate the power system when an out-of-step between two groups of generators within it is predicted. The out-of-step prediction method is based on the generator's angular-velocity data measured by electromagnetic sensors and gears that are fastened directly to the rotors. The equipment was tested by the large-scale power system simulator APSA (Advanced Power System Analyzer), that is installed in the Kansai Electric Power Co., Inc. The equipment also underwent a field test.
Power law in the angular velocity distribution of a granular needle
Piasecki, J.; Viot, P.
2005-01-01
We show how inelastic collisions induce a power law with exponent -3 in the decay of the angular velocity distribution of anisotropic particles with sufficiently small moment of inertia. We investigate this question within the Boltzmann kinetic theory for an elongated granular particle immersed in a bath. The power law persists so long as the collisions are inelastic for a large range of angular velocities provided the mass ratio of the anisotropic particle and the bath particles remains smal...
Narrow structures observed in the p-p analyzing power
The momentum dependence of the p-p elastic analyzing power has been measured in small steps using an internal target during polarized beam acceleration from 1 to 3 GeV/c. The momentum bin size ranges from 5 to 18 MeV/c. The relative uncertainty of the analyzing power is typically less than 0.01 for each momentum bin. Narrow structures have been observed in the two-proton invariant mass distribution of the analyzing power. A brief discussion on the interpretation of the present results is also given. 11 refs., 7 figs., 1 tab
We report on the development of a full operational rotating analyzer spectroscopic ellipsometer. This instrument employs a phase-sensitive amplifier to process the optical signal as an alternative to Fast Fourier Transform analysis. We describe electronic hardware designed to stabilize the rotation frequency of the analyzer prism as well as to drive the device for the positioning of the polarizer prism azimuth. The ellipsometer allows for dielectric function measurement in the energy range from 1.7-5.5 eV, in both ambient air and Ultra High Vacuum (UHV). UHV measurements can be carried out at a temperature as low as 150 K. To evaluate the ellipsometer performance we present results of the determination of the complex dielectric function of a number of semiconductors, namely, GaSb, GaAs, InGaAs, CdTe and CdHgTe. (Author)
Flores C, J.M.; Nunez O, O.F.; Rodriguez P, G.; Lastras M, A.; Lastras M, L.F. [Instituto de Investigacion en Comunicacion Optica, Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi (Mexico)
2005-07-01
We report on the development of a full operational rotating analyzer spectroscopic ellipsometer. This instrument employs a phase-sensitive amplifier to process the optical signal as an alternative to Fast Fourier Transform analysis. We describe electronic hardware designed to stabilize the rotation frequency of the analyzer prism as well as to drive the device for the positioning of the polarizer prism azimuth. The ellipsometer allows for dielectric function measurement in the energy range from 1.7-5.5 eV, in both ambient air and Ultra High Vacuum (UHV). UHV measurements can be carried out at a temperature as low as 150 K. To evaluate the ellipsometer performance we present results of the determination of the complex dielectric function of a number of semiconductors, namely, GaSb, GaAs, InGaAs, CdTe and CdHgTe. (Author)
np elastic scattering analyzing power characteristics at intermediate energies
Recent measurements of charge symmetry breaking in the np system at 477 MeV, and of Aoonn for np elastic scattering at 220, 325 and 425 MeV also yield accurate analyzing power data. These data allow the energy dependence of the analyzing power zero-crossing angle and the slope of the analyzing power at the zero-crossing to be determined. The incident neutron energies span a region where the zero-crossing angle is strongly energy dependent (Εn n > 350 MeV). The results are compared to current phase shift analysis predictions, recently published LAMPF data, and the predictions of the Bonn and Paris potentials. (Author) 13 refs., 2 tabs., 2 figs
Time asymmetry: Polarization and analyzing power in the nuclear reactions
Measurements of the proton polarization in the reactions 7Li(3He, p vector)9Be and 9Be(3He, p vector)11B and of the analyzing powers of the inverse reactions, initiated by polarized protons at the same c.m. energies, show significant differences which imply the failure of the polarization-analyzing-power theorem and, prima facie, of time-reversal invariance in these reactions. The reaction 2H(3He, p vector)4 He and its inverse have also been investigated and show some smaller differences. A discussion of the instrumental asymmetries is presented. (orig.)
Monitoring and analyzing features of electrical power quality system performance
Genci Sharko
2010-06-01
Full Text Available Power quality is a set of boundaries that allows electrical systems to function in their intended manner without significant loss of performance or life. The term is used to describe electric power that drives an electrical load and the load's ability to function properly with that electric power. Without the proper quality of the power, an electrical device may malfunction, fail prematurely or not operate at all. There are many reasons why the electric power can be of poor quality and many more causes of such poor quality power. Power quality of power systems, which affects all connected electrical and electronic equipment, is a measure of deviations in voltages, currents, frequency, temperatures, winding forces and torques of particular supply systems and their components. In recent years, a considerable increase in nonlinear loads has been experienced; in particular distributed loads, such as computers, monitors and lighting, and distributed sources. The aim of this paper is to display a way of monitoring and analyzing features of electrical power quality system. As a monitoring example is taken output from power transformer rated at 320 kVA, part of distribution grid of Durres City in Albania.
Estimating Discrete Power Angular Spectra in Multiprobe OTA Setups
Fan, Wei; Nielsen, Jesper Ødum; Pedersen, Gert Frølund
2014-01-01
accurate direction-of-arrival estimates as well as power estimates of the impinging signals in the test zone. Simulation results match well with the target, as expected. Measurement results based on a virtual UCA in a practical 3-D multiprobe setup further support the simulation results. Possible reasons...
Analyzing Single-Event Gate Ruptures In Power MOSFET's
Zoutendyk, John A.
1993-01-01
Susceptibilities of power metal-oxide/semiconductor field-effect transistors (MOSFET's) to single-event gate ruptures analyzed by exposing devices to beams of energetic bromine ions while applying appropriate bias voltages to source, gate, and drain terminals and measuring current flowing into or out of each terminal.
Low Power Compact Radio Galaxies at High Angular Resolution
Giroletti, Marcello; Giovannini, G.; /Bologna U. /Bologna, Ist. Radioastronomia; Taylor, G.B.; /KIPAC, Menlo Park /NRAO, Socorro
2005-06-30
We present sub-arcsecond resolution multi-frequency (8 and 22 GHz) VLA images of five low power compact (LPC) radio sources, and phase referenced VLBA images at 1.6 GHz of their nuclear regions. At the VLA resolution we resolve the structure and identify component positions and flux densities. The phase referenced VLBA data at 1.6 GHz reveals flat-spectrum, compact cores (down to a few milliJansky) in four of the five sources. The absolute astrometry provided by the phase referencing allows us to identify the center of activity on the VLA images. Moreover, these data reveal rich structures, including two-sided jets and secondary components. On the basis of the arcsecond scale structures and of the nuclear properties, we rule out the presence of strong relativistic effects in our LPCs, which must be intrinsically small (deprojected linear sizes {approx}< 10 kpc). Fits of continuous injection models reveal break frequencies in the GHz domain, and ages in the range 10{sup 5}-10{sup 7} yrs. In LPCs, the outermost edge may be advancing more slowly than in more powerful sources or could even be stationary; some LPCs might also have ceased their activity. In general, the properties of LPCs can be related to a number of reasons, including, but not limited to: youth, frustration, low kinematic power jets, and short-lived activity in the radio.
A DEPLHI BASED POWER MONITORING SOFTWARE DEVELOPED FOR ENERGY ANALYZERS
A. Serdar YILMAZ
2006-03-01
Full Text Available In this paper, a Delphi based interface software developed for energy analyzers is presented. Transferring the electrical parameters which is read from the energy analyzer to the computer in real-time has been achieved by using the developed software. It is also possible to record the parameters such as current, voltage, power, harmonic distortion and etc in real-time and to illustrate these recorded parameters in comparison with each other and graphically. Presented software is developed for Merlin Gerin Powerlogic PM 800 power analyzers and also it is usable for different trademarks and models which use Modbus protocol. Proposed software permits intercommunication and observation between maximum 256 devices. Recorded data can be monitorized in table and graphic form for requested time and date intervals by the users. In the study, Borland Delphi v.7.0 is preferred due to flexible and fast. Developed software can be easily used for energy distribution automation and monitoring of the power flow and power quality and also it is a user friendly interface.
Analyzing the Low Power Wireless Links for Wireless Sensor Networks
Mamun, Md Mainul Islam; Kumar, Sumon; Islam, Md Zahidul
2010-01-01
There is now an increased understanding of the need for realistic link layer models in the wireless sensor networks. In this paper, we have used mathematical techniques from communication theory to model and analyze low power wireless links. Our work provides theoretical models for the link layer showing how Packet Reception Rate vary with Signal to Noise Ratio and distance for different modulation schemes and a comparison between MICA2 and TinyNode in terms of PRR.
Vector and tensor analyzing powers in deuteron-proton breakup
Vector and tensor analyzing powers of the 1H(d-bar,pp)n breakup reaction at 130 and 100 MeV deuteron beam energies have been measured at KVI Groningen with the use of the detection systems covering large fractions of the phase space. The high precision data are compared to the theoretical predictions based on various approaches to describe the three nucleon (3N) system dynamics. Theoretical predictions describe very well the vector analyzing power data, with no need to include any three-nucleon force effects for these observables. The tensor analyzing powers can be also very well reproduced by calculations in most of the studied region, but locally certain discrepancies are observed. At 130 MeV for Axy such discrepancies usually appear, or are enhanced, when model 3N forces (3NFs), TM99 or Urbana IX, are included. Problems of all theoretical approaches with describing Axx and Ayy are limited to very small regions of the phase space, usually characterized with the lowest relative energies of the two protons. Predicted effects of 3NFs are much lower at 100 MeV, therefore at this energy equally good consistency between the data and the calculations is obtained with or without 3NFs.
Ruhl, J E; Bock, J J; Bond, J R; Borrill, J; Boscaleri, A; Contaldi, C R; Crill, B P; De Bernardis, P; De Troia, G; Ganga, K; Giacometti, M; Hivon, E; Hristov, V V; Iacoangeli, A; Jaffe, A H; Jones, W C; Lange, A E; Masi, S; Mason, P; Mauskopf, P D; Melchiorri, A; Montroy, T; Netterfield, C B; Pascale, E; Piacentini, F; Pogosyan, D; Polenta, G; Prunet, S; Romeo, G
2003-01-01
We report the most complete analysis to date of observations of the Cosmic Microwave Background (CMB) obtained during the 1998 flight of BOOMERANG. We use two quite different methods to determine the angular power spectrum of the CMB in 20 bands centered at l = 50 to 1000, applying them to 50% more data than has previously been analyzed. The power spectra produced by the two methods are in good agreement with each other, and constitute the most sensitive measurements to date over the range 300 < l < 1000. The increased precision of the power spectrum yields more precise determinations of several cosmological parameters than previous analyses of BOOMERANG data. The results continue to support an inflationary paradigm for the origin of the universe, being well fit by a 13.5 Gyr old, flat universe composed of approximately 5% baryonic matter, 30% cold dark matter, and 65% dark energy, with a scale invariant initial density perturbations.
Using Model Checking for Analyzing Distributed Power Control Problems
Thomas Brihaye
2010-01-01
Full Text Available Model checking (MC is a formal verification technique which has been known and still knows a resounding success in the computer science community. Realizing that the distributed power control (PC problem can be modeled by a timed game between a given transmitter and its environment, the authors wanted to know whether this approach can be applied to distributed PC. It turns out that it can be applied successfully and allows one to analyze realistic scenarios including the case of discrete transmit powers and games with incomplete information. The proposed methodology is as follows. We state some objectives a transmitter-receiver pair would like to reach. The network is modeled by a game where transmitters are considered as timed automata interacting with each other. The objectives are then translated into timed alternating-time temporal logic formulae and MC is exploited to know whether the desired properties are verified and determine a winning strategy.
The EDDA experiment at the cooler synchrotron COSY measures proton-proton elastic scattering excitation functions in the momentum range 0.8 - 3.4 GeV/c. In phase 1 of the experiment, spin-averaged differential cross sections were measured continuously during acceleration with an internal polypropylene (CH2) fiber target, taking particular care to monitor luminosity as a function of beam momentum. In phase 2, excitation functions of the analyzing power AN and the polarization correlation parameters ANN, ASS and ASL are measured using a polarized proton beam and a polarized atomic hydrogen beam target. The paper presents recent dσ/dΩ and AN data. The results provide excitation functions and angular distributions of high precision and internal consistency. No evidence for narrow structures was found. The data are compared to recent phase shift solutions
Analyzing power in the mass-six supermultiplet system
Analyzing powers Asub(y) for reactions leading to several members of the mass-six supermultiplet have been measured via the t(pol)+9Be→6Li + 6He, 6Li*+6He reactions at 17 MeV triton energy. In contrast to the previously measured differential cross sections, which show symmetry about 900 for both the S=1 and S=0 channels. Asub(y) is consistent with being antisymmetry about 900 for the S=0 channel and is approximately symmetric for the S=1 channel. An antisymmetric result for the S=0 isospin-multiplet channel could be understood by invoking isospin symmetry, in analogy to the well-known Barshay-Temmer theorem. The reaction leading to the S=1 channel is discussed in terms of a direct reaction mechanism; however, the symmetry of Asub(y) about 900 is not understood. (Auth.)
Governance of Aquatic Agricultural Systems: Analyzing Representation, Power, and Accountability
Blake D. Ratner
2013-12-01
Full Text Available Aquatic agricultural systems in developing countries face increasing competition from multiple stakeholders over rights to access and use natural resources, land, water, wetlands, and fisheries, essential to rural livelihoods. A key implication is the need to strengthen governance to enable equitable decision making amidst competition that spans sectors and scales, building capacities for resilience, and for transformations in institutions that perpetuate poverty. In this paper we provide a simple framework to analyze the governance context for aquatic agricultural system development focused on three dimensions: stakeholder representation, distribution of power, and mechanisms of accountability. Case studies from Cambodia, Bangladesh, Malawi/Mozambique, and Solomon Islands illustrate the application of these concepts to fisheries and aquaculture livelihoods in the broader context of intersectoral and cross-scale governance interactions. Comparing these cases, we demonstrate how assessing governance dimensions yields practical insights into opportunities for transforming the institutions that constrain resilience in local livelihoods.
Acoustic scale from the angular power spectra of SDSS-III DR8 photometric luminous galaxies
Seo, Hee-Jong; White, Martin; Cuesta, Antonio; Ross, Ashley; Saito, Shun; Reid, Beth; Padmanabhan, Nikhil; Percival, Will J; de Putter, Roland; Schlegel, David; Eisenstein, Daniel; Xu, Xiaoying; Schneider, Donald; Skibba, Ramin; Verde, Licia; Nichol, Robert; Bizyaev, Dmitry; Brewington, Howard; Brinkmann, J; Costa, Luiz; Gott, J; Malanushenko, Elena; Malanushenko, Viktor; Oravetz, Dan; Palanque-Delabrouille, Nathalie; Pan, Kaike; Prada, Francisco; Ross, Nicholas; Simmons, Audrey; Simoni, Fernando; Shelden, Alaina; Snedden, Stephanie; Zehavi, Idit
2012-01-01
We measure the acoustic scale from the angular power spectra of the Sloan Digital Sky Survey III (SDSS-III) Data Release 8 imaging catalog that includes 872,921 galaxies over ~ 10,000 deg^2 between 0.45~ 0.35. We report constraints on cosmological parameters from our measurement in combination with the WMAP7 data and the previous spectroscopic BAO measurements of SDSS (Percival et al. 2010) and WiggleZ (Blake et al. 2011). We refer to our companion papers (Ho et al. 2011; de Putter et al. 2011) for investigations on information of the full power spectrum.
At the Swiss Institute for Nuclear Research angular distributions and analyzing power of the elastic pion-deuteron scattering was measured. Then pion energies amount 142, 219, 256, 275, 294, and 325 MeV. The alignment for deuteron spins resulted by the method of the dynamic nuclear polarization. The measurements were performed in two independent experiments. In the first experiment the scattered pions were detected by a magnetic spectrometer. The second experiment used the time-of-flight difference between elastically scattered pions and the corresponding recoil deuterons for the identification of an elastic πd scattering event. The angular distributions of the elastic vector analysing power exhibit a characteristic energy slope. From 256 MeV a minimum in the forward angular range is present which becomes with increasing energy ever more negative. Calculation in the three-body formalism cannot describe this slope from 256 MeV. A procedure which mixes to this theory a 1D2 and 1G4 dibargon resonance yields qualitatively good descriptions of the data. In order to establish resonance effects independently of models the available experimental data were subjected to a scattering phase analysis. The adjustment of small (orbital angular momenta L 1G4 resonance. (orig.)
WIND TURBINE SIMULATION FOR TIME-DEPENDENT ANGULAR VELOCITY, TORQUE, AND POWER
YONGHO LEE
2013-02-01
Full Text Available Albeit the prediction of time-dependent properties of wind turbines is not required for common applications, such time-varying properties may play an important role during transient operations occurring due to various reasons. Unlike the conventional numerical simulations of wind turbine rotations that fix the angular velocity to an assumed value, the present work numerically simulates the time-varying turbine rotation in both unsteady and quasi-steady operation regimes, without specifying the angular velocity of the turbine a priori, but by calculating the actual time-dependent angular velocity and aerodynamic torque along with other properties in the course of simulation. In the present work, successful results obtained by an efficient computational fluid dynamics technique are shown, as a demonstration, for a vertical-axis wind turbine with a two-dimensionalSavonius rotor, and the cycle-averaged output powers are compared with experimental power curves and a theory developed on the basis of experimental observations.
Javahiraly, Nicolas; Chakari, Ayoub
2013-05-01
To achieve a very effective automotive power steering system, we need two important data, the angular position of the wheel and the torque applied on the shaft by the driver of the car. We present a new accurate optical fiber angular position sensor connected to an automotive power steering column. In this new design, the sensor allows the measurement of the angular position of a car steering wheel over a large and adjustable range (± several turns of the wheel). The wheel rotation induces micro-bending in the transducer part of the optical fiber sensing system. This system operates as an amplitude modulation sensor based on mode coupling in the transducing fiber in the case when all the modes are equally excited. We study the sensor response both theoretically and experimentally with a multimode step index optical fiber [rf (fiber radius) = 300 μm rc (core radius) = 50 μm nc (core index) = 1,457; N.A. = 0, 22 and the wavelength is 632,8 nm at the ambient Temperature (20°C)]. We show that the sensitivity can be controlled as a function of the sensor's length. We compare modeling and experimental validation and we conclude with a perspective on what could soon be an industrial sensor.
Analyzing powers Ayy, Axx, Axz and Ay in the dd→3Hen reaction at 270 MeV
The data on the tensor Ayy, Axx, Axz and vector Ay analyzing powers in the dd→3Hen reaction obtained at Td=270 MeV in the angular range 0-110 deg in the c.m. are presented. The observed negative sign of the tensor analyzing powers Ayy, Axx and Axz at small angles clearly demonstrates the sensitivity to the ratio of the D- and S-wave component of the 3He wave function. However, the one-nucleon exchange calculations by using the standard 3He wave functions have failed to reproduce the strong variation of the tensor analyzing powers as a function of the angle in the c.m
Ebersole, K T; Housh, T J; Weir, J P; Johnson, G O; Evetovich, T K; Smith, D B
2000-01-01
The purpose of the present investigation was to examine the effects of leg angular velocity on the mean power frequency (MPF) and amplitude of the mechanomyographic (MMG) signal during maximal concentric (CON) isokinetic muscle actions. Sixteen adult subjects performed maximal CON leg extensions on a calibrated Cybex 6000 dynamometer at leg angular velocities of 60 and 300 degrees.s-1. MMG was detected by a piezoelectric crystal contact sensor placed over the mid-portion of the vastus lateralis muscle. The results indicated a significant (p 0.05) in MMG MPF. These findings did not support our hypothesis that increases across velocity in MMG amplitude were due to decreases in muscle stiffness as a result of a shift in the contribution of slow and fast-twitch muscle fibers to PT production. Future research should examine the potential influence of actin-myosin cycling rate as well as limb movement on the MPF and amplitude of the MMG signal. PMID:10782358
The optimization of spectrum in the power analyzer
Wu, R.C.; Chen, H.M. [I-Shou Univ., Kaohsiung, Taiwan (China). Dept. of Electrical Engineering; Ou, T.C. [National Sun Yat-Sen Univ., Kaohsiung, Taiwan (China). Dept. of Electrical Engineering; Tsai, J.I. [Kao Yuan Univ., Kaohsiung, Taiwan (China). Dept. of Electronic Engineering
2008-07-01
A study was conducted to investigate spectra under different sampling rates by amplitude summation and purpose V curve. The objective was to promote the accuracy of the spectrum in the power analyzer, which is influenced by different sampling rates. The study revealed that as soon as an optimal sampling rate is determined, an optimal spectrum can also be determined. Since the relationship between the amplitude summation and the sampling rate is that of a type V curve, the optimal solution can be obtained quickly. The study also compared results of Fast Fourier Transformation (FFT) and the optimal spectrum to prove the accuracy of this method. This method also offers a solution to common errors, including the picket-fence effect and leakage effect which result from the sampling period being different to the time of the signal period. By adjusting the sampling rate, the frequency scale can be changed to match the signal parameter. As such, the leakage effect can be eliminated and the exact parameter can be displayed on the spectrum. 10 refs., 3 tabs., 5 figs.
Effect of the length of inflation on angular TT and TE power spectra in power-law inflation
Hirai, S; Hirai, Shiro; Takami, Tomoyuki
2006-01-01
The effect of the length of inflation on the power spectra of scalar and tensor perturbations is estimated using the power-law inflation model with a scale factor of a(t) = t^q. Considering various pre-inflation models with radiation-dominated or scalar matter-dominated periods before inflation in combination with two matching conditions, the temperature angular power spectrum (TT) and temperature-polarization cross-power spectrum (TE) are calculated and a likelihood analysis is performed. It is shown that the discrepancies between the Wilkinson Microwave Anisotropy Probe (WMAP) data and the LCDM model, such as suppression of the spectrum at l = 2,3 and oscillatory behavior, may be explained by the finite length of inflation model if the length of inflation is near 60 e-folds and q > 300. The proposed models retain similar values of chi^2 to that achieved by the LCDM model with respect to fit to the WMAP data, but display different characteristics of the angular TE power spectra at l < 20.
Effect of the length of inflation on angular TT and TE power spectra in power-law inflation
The effect of the length of inflation on the power spectra of scalar and tensor perturbations is estimated using the power-law inflation model with a scale factor of a(η) = (-η)p = tq. Considering various pre-inflation models with radiation-dominated or scalar matter-dominated periods before inflation in combination with two matching conditions, the temperature angular power spectrum (TT) and temperature-polarization cross-power spectrum (TE) are calculated and a likelihood analysis is performed. It is shown that the discrepancies between the Wilkinson microwave anisotropy probe (WMAP) data and the ΛCDM model, such as suppression of the spectrum at l = 2, 3 and oscillatory behaviour, may be explained by the finite length of inflation model if the length of inflation is near 60 e-folds and q ≥ 300. The proposed models retain similar values of χ2 to that achieved by the ΛCDM model with respect to fit to the WMAP data, but display different characteristics of the angular TE power spectra at l ≤ 20
Using the CMB angular power spectrum to study Dark Matter-photon interactions
Wilkinson, Ryan J.; Boehm, Céline [Institute for Particle Physics Phenomenology, Durham University, South Road, Durham, DH1 3LE United Kingdom (United Kingdom); Lesgourgues, Julien, E-mail: ryan.wilkinson@durham.ac.uk, E-mail: julien.lesgourgues@cern.ch, E-mail: c.m.boehm@durham.ac.uk [Institut de Théorie des Phénomènes Physiques, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015 (Switzerland)
2014-04-01
In this paper, we explore the impact of Dark Matter-photon interactions on the CMB angular power spectrum. Using the one-year data release of the Planck satellite, we derive an upper bound on the Dark Matter-photon elastic scattering cross section of σ{sub DM−γ} ≤ 8 × 10{sup −31} (m{sub DM}/GeV) cm{sup 2} (68% CL) if the cross section is constant and a present-day value of σ{sub DM−γ} ≤ 6 × 10{sup −40}(m{sub DM}/GeV) cm{sup 2} (68% CL) if it scales as the temperature squared. For such a limiting cross section, both the B-modes and the TT angular power spectrum are suppressed with respect to ΛCDM predictions for ℓ∼>500 and ℓ∼>3000 respectively, indicating that forthcoming data from CMB polarisation experiments and Planck could help to constrain and characterise the physics of the dark sector. This essentially initiates a new type of dark matter search that is independent of whether dark matter is annihilating, decaying or asymmetric. Thus, any CMB experiment with the ability to measure the temperature and/or polarisation power spectra at high ℓ should be able to investigate the potential interactions of dark matter and contribute to our fundamental understanding of its nature.
Using the CMB angular power spectrum to study Dark Matter-photon interactions
In this paper, we explore the impact of Dark Matter-photon interactions on the CMB angular power spectrum. Using the one-year data release of the Planck satellite, we derive an upper bound on the Dark Matter-photon elastic scattering cross section of σDM−γ ≤ 8 × 10−31 (mDM/GeV) cm2 (68% CL) if the cross section is constant and a present-day value of σDM−γ ≤ 6 × 10−40(mDM/GeV) cm2 (68% CL) if it scales as the temperature squared. For such a limiting cross section, both the B-modes and the TT angular power spectrum are suppressed with respect to ΛCDM predictions for ℓ∼>500 and ℓ∼>3000 respectively, indicating that forthcoming data from CMB polarisation experiments and Planck could help to constrain and characterise the physics of the dark sector. This essentially initiates a new type of dark matter search that is independent of whether dark matter is annihilating, decaying or asymmetric. Thus, any CMB experiment with the ability to measure the temperature and/or polarisation power spectra at high ℓ should be able to investigate the potential interactions of dark matter and contribute to our fundamental understanding of its nature
Lee, Jounghun
2008-01-01
We analyze the photometric redshift catalog of the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) to estimate the Fisher information in the galaxy angular power spectrum with the help of the Rimes-Hamilton technique. It is found that the amount of Fisher information contained in the galaxy angular power spectrum is saturated at lensing multipole scale 300<= l <= 2000 in the redshift range 0.1<= photo-z <0.5. At l=2000, the observed information is two orders of magnitude lower than the case of Gaussian fluctuations. This supports observationally that the translinear regime of the density power spectrum contains little independent information about the initial cosmological conditions, which is consistent with the numerical trend shown by Rimes-Hamilton. Our results also suggest that the Gaussian-noise description may not be valid in weak lensing measurements.
Yoon, Changwoo; Bai, Haofeng; Wang, Xiongfei; Bak, Claus Leth; Blaabjerg, Frede
2015-01-01
Stability analysis of distributed power generation system becomes complex when there are many numbers of grid inverters in the system. In order to analyze system stability, the overall network impedance will be lumped and needs to be analyzed one by one. However, using a unified bulky transfer......-function creates an ambiguity of knowing the reason of instability and also there is no fixed way of choosing the sequence of the analysis. This paper suggests a method to perform a regional stability analysis in the distribution power system. The main idea is started from the simplest stability analysis entity...
Angular Power Spectrum and Dilatonic Inflation in Modular-Invariant Supergravity
Hayashi, M J; Okame, Y; Watanabe, T; Hayashi, Mitsuo J.; Hirai, Shiro; Okame, Yusuke; Watanabe, Tomoki
2006-01-01
The angular power spectrum is investigated in the model of supergravity, incorporating the target-space duality and the non-perturbative gaugino condensation in the hidden sector. The inflation and supersymmetry breaking occur at once by the interplay between the dilaton field as inflaton and the condensate gauge-singlet field. The model satisfies the slow-roll condition which solves the \\eta-problem. When the particle rolls down along the minimized trajectory of the potential at a duality invariant fixed point T=1, we can obtain the e-fold value \\sim 57. And then the cosmological parameters obtained from our model well match with the recent WMAP data combined with other experiments. The TT and TE angular power spectra also show that our model is compatible with the data for l > 20. However, the best fit value of \\tau in our model is smaller than that of the \\Lambda CDM model. These results suggest that, among supergravity models of inflation, the modular-invariant supergravity seems to open a hope to constru...
Power quality analyzer device modeling by real time SIMULINK MATLAB
Martins, C.H.N.; Silva, L.R.M.; Fabri, D.F.; Duque, C.A. [Federal University of Juiz de Fora (UFJF), MG (Brazil)], Emails: chnmartins@yahoo.com.br, leandro.manso@engenharia.ufjf.br, Diego.fabri@engenharia.ufjf.br, Carlos.duque@ufjf.br; Ribeiro, P.F. [Calvin College, Grand Rapids, MI (United States)], E-mail: pfribeiro@ieee.org
2009-07-01
The expansion of electronic devices have increased non linear loads. The effect is high levels of electric disturbances and EMC and EMI interferences. The control of power quality parameters are of primordial importance to ensure minimal power quality. This paper deals with the modeling, simulation and development of a device capable of measuring electrical events. (author)
Using the CMB angular power spectrum to study Dark Matter-photon interactions
Wilkinson, Ryan J; Boehm, Celine
2014-01-01
In this paper, we explore the impact of Dark Matter-photon interactions on the CMB angular power spectrum. Using the one-year data release of the Planck satellite, we derive an upper bound on the Dark Matter-photon elastic scattering cross section of sigma_{DM-photon} 500 and l > 3000 respectively, indicating that forthcoming data from CMB polarisation experiments and Planck could help to constrain and characterise the physics of the dark sector. This essentially initiates a new type of dark matter search that is independent of whether dark matter is annihilating, decaying or asymmetric. Thus, any CMB experiment with the ability to measure the temperature and/or polarisation power spectra at high l should be able to investigate the potential interactions of dark matter and contribute to our fundamental understanding of its nature.
Using Model Checking for Analyzing Distributed Power Control Problems
Brihaye, Thomas; Jungers, Marc; Lasaulce, Samson; Markey, Nicolas; Oreiby, Ghassan
2010-01-01
Model checking (MC) is a formal verification technique which has been known and still knows a resounding success in the computer science community. Realizing that the distributed power control ( PC) problem can be modeled by a timed game between a given transmitter and its environment, the authors...
Angular power spectrum of sterile neutrino decay lines: the role of eROSITA
Zandanel, Fabio; Weniger, Christoph; Ando, Shin’ichiro
2016-05-01
We study the potential of the angular auto and cross-correlation power spectrum of the cosmic X-ray background in identifying sterile neutrino dark matter taking as reference the performances of the soon-to-be-launched eROSITA satellite. The main astrophysical background sources in this case are active galactic nuclei, galaxies powered by X-ray binaries, and clusters of galaxies. We show that while sterile neutrino decays are always subdominant in the autocorrelation power spectra, they can be efficiently enhanced when cross-correlating with tracers of the dark matter distribution. We estimate that the four-years eROSITA all-sky survey will potentially provide very stringent constraints on the sterile neutrino decay lifetime by cross-correlating the cosmic X-ray background with the 2MASS galaxy catalogue. This will allow to firmly test the recently claimed 3.56-keV X-ray line found towards several clusters and galaxies and its decaying dark matter interpretation. We finally stress that the main limitation of this approach is due to the shot noise of the galaxy catalogues used as tracers for the dark matter distribution, a limitation that we need to overcome to fully exploit the potential of the eROSITA satellite in this context.
The angular power spectra of photometric Sloan Digital Sky Survey luminous red galaxies
Thomas, Shaun A.; Abdalla, Filipe B.; Lahav, Ofer
2011-04-01
We construct new galaxy angular power spectra Cℓ based on the extended, updated and final Sloan Digital Sky Survey (SDSS) II luminous red galaxy (LRG) photometric redshift survey - MegaZ (DR7). Encapsulating 7746 deg2 we utilize 723 556 photometrically determined LRGs between 0.45 preliminary parameter constraints of fb≡Ωb/Ωm= 0.173 ± 0.046 and Ωm= 0.260 ± 0.035 assuming H0= 75 km s-1 Mpc-1, ns= 1 and Ωk= 0. These limits are consistent with the cosmic microwave background and the previous data release (DR4). The Cℓ are sensitive to redshift space distortions and therefore we also recast our constraints into a measurement of β≈Ω0.55m/b in different redshift shells. The robustness of these power spectra with respect to a number of potential systematics such as extinction, photometric redshift and ANNz training set extrapolation are examined. The latter includes a cosmological comparison of available photometric redshift estimation codes where we find excellent agreement between template and empirical estimation methods. MegaZ DR7 represents a methodological prototype to next generation surveys such as the Dark Energy Survey and, furthermore, is a photometric precursor to the spectroscopic BOSS survey. Our galaxy catalogue and all power spectra data can be found at .
Highlights: • A calibration method for the transmission function of modern XPS analyser is shown. • This method can be applied to any soft X-ray photoemission setup. • Ray tracing calculations well agree with experimental results. • A fine calibration is carried out through variable photon energy XPS. • An escape depth correction must be included in the calibration process. - Abstract: In order to achieve the most accurate quantification results in an X-ray photoelectron spectroscopy (XPS) experiment, a fine calibration of the analyzer response is required. In this work an experimental characterization of a modern angle-resolved analyzer, carried out with a unfocused and a highly collimated synchrotron source, is shown. The transmission function is extrapolated from the discrepancy between experimental and theoretically predicted XPS peak areas; the influence of different sensitivity factors and of the escape depth correction on the expected values is also discussed. The analyzer response and the theoretical approach are then tested against energy dispersive XPS measurements (EDXPS). These results are finally compared with TF calculated on the basis of an high accuracy electron ray tracing code, also described in this work
Surface chemistry of InP ridge structures etched in Cl{sub 2}-based plasma analyzed with angular XPS
Bouchoule, Sophie, E-mail: sophie.bouchoule@lpn.cnrs.fr; Cambril, Edmond; Guilet, Stephane [Laboratoire de Photonique et Nanostructure (LPN)—UPR20, CNRS, Route de Nozay, 91460 Marcoussis (France); Chanson, Romain; Pageau, Arnaud; Rhallabi, Ahmed; Cardinaud, Christophe, E-mail: christophe.cardinaud@cnrs-imn.fr [Institut des matériaux Jean Rouxel (IMN), UMR6502, Université de Nantes, CNRS, 44322 Nantes (France)
2015-09-15
Two x-ray photoelectron spectroscopy configurations are proposed to analyze the surface chemistry of micron-scale InP ridge structures etched in chlorine-based inductively coupled plasma (ICP). Either a classical or a grazing configuration allows to retrieve information about the surface chemistry of the bottom surface and sidewalls of the etched features. The procedure is used to study the stoichiometry of the etched surface as a function of ridge aspect ratio for Cl{sub 2}/Ar and Cl{sub 2}/H{sub 2} plasma chemistries. The results show that the bottom surface and the etched sidewalls are P-rich, and indicate that the P-enrichment mechanism is rather chemically driven. Results also evidence that adding H{sub 2} to Cl{sub 2} does not necessarily leads to a more balanced surface stoichiometry. This is in contrast with recent experimental results obtained with the HBr ICP chemistry for which fairly stoichiometric surfaces have been obtained.
Estimation of the angular power spectrum is one of the important steps in Cosmic Microwave Background (CMB) data analysis. Here, we present a nonparametric estimate of the temperature angular power spectrum for the Planck 2013 CMB data. The method implemented in this work is model-independent, and allows the data, rather than the model, to dictate the fit. Since one of the main targets of our analysis is to test the consistency of the ΛCDM model with Planck 2013 data, we use the nuisance parameters associated with the best-fit ΛCDM angular power spectrum to remove foreground contributions from the data at multipoles ℓ ≥50. We thus obtain a combined angular power spectrum data set together with the full covariance matrix, appropriately weighted over frequency channels. Our subsequent nonparametric analysis resolves six peaks (and five dips) up to ℓ ∼1850 in the temperature angular power spectrum. We present uncertainties in the peak/dip locations and heights at the 95% confidence level. We further show how these reflect the harmonicity of acoustic peaks, and can be used for acoustic scale estimation. Based on this nonparametric formalism, we found the best-fit ΛCDM model to be at 36% confidence distance from the center of the nonparametric confidence set—this is considerably larger than the confidence distance (9%) derived earlier from a similar analysis of the WMAP 7-year data. Another interesting result of our analysis is that at low multipoles, the Planck data do not suggest any upturn, contrary to the expectation based on the integrated Sachs-Wolfe contribution in the best-fit ΛCDM cosmology
Krasina, E.A.; Nevezhin, O.A.; Rubanovich, I.M.
1976-01-01
The example of a solar thermoemission power plant is used for the analysis of certain features of solar-power-plant operating regimes for various radiation densities and angular sizes of the radiation source. The calculations are performed both on the assumption of exact pointing of the collector optical axis at the radiation source and with allowance for error. Results are reported for plant-efficiency optimization calculations, together with data on the permissible error angles of the solar tracking system.
Fornasa, Mattia; Zavala, Jesus; Gaskins, Jennifer M; Sanchez-Conde, Miguel A; Gomez-Vargas, German; Komatsu, Eiichiro; Linden, Tim; Prada, Francisco; Zandanel, Fabio; Morselli, Aldo
2016-01-01
The isotropic gamma-ray background arises from the contribution of unresolved sources, including members of confirmed source classes and proposed gamma-ray emitters such as the radiation induced by dark matter annihilation and decay. Clues about the properties of the contributing sources are imprinted in the anisotropy characteristics of the gamma-ray background. We use 81 months of Pass 7 Reprocessed data from the Fermi Large Area Telescope to perform a measurement of the anisotropy angular power spectrum of the gamma-ray background. We analyze energies between 0.5 and 500 GeV, extending the range considered in the previous measurement based on 22 months of data. We also compute, for the first time, the cross-correlation angular power spectrum between different energy bins. We find that the derived angular spectra are compatible with being Poissonian, i.e. constant in multipole. Moreover, the energy dependence of the anisotropy suggests that the signal is due to two populations of sources, contributing, resp...
Analyzing Small Signal Stability of Power System based on Online Data by Use of SMES
Ishikawa, Hiroyuki; Shirai, Yasuyuki; Nitta, Tanzo; Shibata, Katsuhiko
The purpose of this study is to estimate eigen-values and eigen-vectors of a power system from on-line data to evaluate the power system stability. Power system responses due to the small power modulation of known pattern from SMES (Superconducting Magnetic Energy Storage) were analyzed, and the transfer functions between the power modulation and power oscillations of generators were obtained. Eigen-values and eigen-vectors were estimated from the transfer functions. Experiments were carried out by use of a model SMES and Advanced Power System Analyzer (APSA), which is an analogue type power system simulator of Kansai Electric Power Company Inc., Japan. Changes in system condition were observed by the estimated eigen-values and eigen-vectors. Result agreed well with the resent report and digital simulation. This method gives a new application for SMES, which will be installed for improving electric power quality.
Alpar, M.A.
1986-12-01
Model power spectra are constructed for quasi-periodic oscillations of the type observed in some galactic bulge X-ray sources. It is shown that the angular location of clumping in the boundary layer, as well as the spread in Keplerian velocities within the boundary layer, will effect the form of the power spectrum under certain conditions. The occurrence of such features in observed power spectra would yield information on the possible role of the magnetic field in clumping and on the radial velocity of matter moving through the boundary layer.
Observation of narrow structures in the p-p analyzing power around 1 GeV
The momentum dependence of the analyzing power Ay in proton-proton elastic scattering has been measured in small steps using an internal target inserted into a polarized proton beam during acceleration from 1 to 3 GeV/c. The momentum bin size ranges from 5 to 18 MeV/c. The relative uncertainty of the analyzing power, ΔAy, is typically less than 0.01 for each momentum bin. Narrow structures have been observed in the two-proton invariant mass distribution of the analyzing power. 15 refs., 5 figs., 1 tab
Near-field angular distributions of high velocity ions for low-power hall thrusters
Sullivan, Regina M.; Yost, Allison; Johnson, Lee K.
2009-01-01
Experimental angular distributions of high-energy primary ions in the near-field region of a small Hall thruster between 50-200 mm downstream of the thruster exit plane at a range of centerline angles have been determined using a highly-collimated, energy-selective diagnostic probe. The measurements reveal a wide angular distribution of ions exiting the thruster channel and the formation of a strong, axially-directed jet of ions along the thruster centerline. Comparisons are made to other exp...
Yang, Hengzhao; Zhang, Ying
2016-04-01
Understanding the power and energy performance of supercapacitors connected to constant power elements is important for many applications. This paper proposes a characterization method for two supercapacitor models that are used to analyze the power and energy behavior of supercapacitors connected to constant power elements: linear capacitance model and constant capacitance model. The linear or constant capacitance is determined by conducting a constant power experiment. A set of constant power experiments is designed. The proposed method can reduce the error in estimating the constant power experiment time for a variety of supercapacitor samples with different rated capacitance and voltage. The accuracy of using the linear capacitance model and the constant capacitance model is approximately equal. Moreover, the performance evaluation results suggest that using the linear or constant capacitance fitted through a low power discharge experiment can minimize the error, which can serve as a guideline to design the constant power experiment.
WIND TURBINE SIMULATION FOR TIME-DEPENDENT ANGULAR VELOCITY, TORQUE, AND POWER
YONGHO LEE
2013-01-01
Albeit the prediction of time-dependent properties of wind turbines is not required for common applications, such time-varying properties may play an important role during transient operations occurring due to various reasons. Unlike the conventional numerical simulations of wind turbine rotations that fix the angular velocity to an assumed value, the present work numerically simulates the time-varying turbine rotation in both unsteady and quasi-steady operation regimes, without specifying th...
We have developed the general-purpose software by which static thermal characteristic of the power generation system is analyzed easily. This software has the notable features as follows. It has the new algorithm to solve non-linear simultaneous equations to analyze the static thermal characteristics such as heat and mass balance, efficiencies, etc. of various power generation systems. It has the flexibility for setting calculation conditions. It is able to be executed on the personal computer easily and quickly. We ensured that it is able to construct heat and mass balance diagrams of main steam system of nuclear power plant and calculate the power output and efficiencies of the system. Furthermore, we evaluated various heat recovery measures of steam generator blowdown water and found that this software could be a useful operation aid for planning effective changes in support of power stretch. (author)
Nakao, Yoshinobu; Koda, Eiichi; Takahashi, Toru
We have developed the general-purpose software by which static thermal characteristic of the power generation system is analyzed easily. This software has the notable features as follows. -It has the new algorithm to solve non-linear simultaneous equations to analyze the static thermal characteristics such as heat and mass balance, efficiencies, etc. of various power generation systems. -It has the flexibility for setting calculation conditions. -It is able to be executed on the personal computer easily and quickly. We ensured that it is able to construct heat and mass balance diagrams of main steam system of nuclear power plant and calculate the power output and efficiencies of the system. Furthermore, we evaluated various heat recovery measures of steam generator blowdown water and found that this software could be a useful operation aid for planning effective changes in support of power stretch.
Synchronized Phasor Data for Analyzing Wind Power Plant Dynamic Behavior and Model Validation
Wan, Y. H.
2013-01-01
The U.S. power industry is undertaking several initiatives that will improve the operations of the power grid. One of those is the implementation of 'wide area measurements' using phasor measurement units (PMUs) to dynamically monitor the operations and the status of the network and provide advanced situational awareness and stability assessment. This project seeks to obtain PMU data from wind power plants and grid reference points and develop software tools to analyze and visualize synchrophasor data for the purpose of better understanding wind power plant dynamic behaviors under normal and contingency conditions.
Analyzing Effects of Turbulence on Power Generation Using Wind Plant Monitoring Data: Preprint
Zhang, J.; Chowdhury, S.; Hodge, B. M.
2014-01-01
In this paper, a methodology is developed to analyze how ambient and wake turbulence affects the power generation of a single wind turbine within an array of turbines. Using monitoring data from a wind power plant, we selected two sets of wind and power data for turbines on the edge of the wind plant that resemble (i) an out-of-wake scenario (i.e., when the turbine directly faces incoming winds) and (ii) an in-wake scenario (i.e., when the turbine is under the wake of other turbines). For each set of data, two surrogate models were then developed to represent the turbine power generation (i) as a function of the wind speed; and (ii) as a function of the wind speed and turbulence intensity. Support vector regression was adopted for the development of the surrogate models. Three types of uncertainties in the turbine power generation were also investigated: (i) the uncertainty in power generation with respect to the published/reported power curve, (ii) the uncertainty in power generation with respect to the estimated power response that accounts for only mean wind speed; and (iii) the uncertainty in power generation with respect to the estimated power response that accounts for both mean wind speed and turbulence intensity. Results show that (i) under the same wind conditions, the turbine generates different power between the in-wake and out-of-wake scenarios, (ii) a turbine generally produces more power under the in-wake scenario than under the out-of-wake scenario, (iii) the power generation is sensitive to turbulence intensity even when the wind speed is greater than the turbine rated speed, and (iv) there is relatively more uncertainty in the power generation under the in-wake scenario than under the out-of-wake scenario.
Selami Kesler
2015-01-01
Full Text Available Shading analyzer systems are necessary for selecting the most suitable installation site to sustain enough solar power. Afterwards, changes in solar data throughout the year must be evaluated along with the identification of obstructions surrounding the installation site in order to analyze shading effects on productivity of the solar power system. In this study, the shading analysis tools are introduced briefly, and a new and different device is developed and explained to analyze shading effect of the environmental obstruction on the site on which the solar power system will be established. Thus, exposure duration of the PV panels to the sunlight can be measured effectively. The device is explained with an application on the installation area selected as a pilot site, Denizli, in Turkey.
Vector and tensor analyzing powers in deuteron-proton breakup reaction
High precision data for vector and tensor analyzing powers of the 1H( d-vector ,pp)n breakup reaction at 130 and 100 MeV deuteron beam energies have been measured in a large fraction of the phase space. They are compared to the theoretical predictions based on various approaches to describe the three nucleon (3N) system dynamics. Theoretical predictions describe very well the vector analyzing power data, with no need to include any three-nucleon force effects for these observables. Tensor analyzing powers can be also very well reproduced by calculations in most of the studied region, but locally certain discrepancies are observed. At 130 MeV for Axy such discrepancies usually appear, or are enhanced, when model 3N forces are included. Predicted effects of 3NFs are much lower at 100 MeV and at this energy equally good consistency between the data and the calculations is obtained with or without 3NFs.
Analyzing the Impact of Solar Power on Multi-Hourly Thermal Generator Ramping
Rosenkranz, Joshua-Benedict; Brancucci Martinez-Anido, Carlo; Hodge, Bri-Mathias
2016-04-08
Solar power generation, unlike conventional forms of electricity generation, has higher variability and uncertainty in its output because solar plant output is strongly impacted by weather. As the penetration rate of solar capacity increases, grid operators are increasingly concerned about accommodating the increased variability and uncertainty that solar power provides. This paper illustrates the impacts of increasing solar power penetration on the ramping of conventional electricity generators by simulating the operation of the Independent System Operator -- New England power system. A production cost model was used to simulate the power system under five different scenarios, one without solar power and four with increasing solar power penetrations up to 18%, in terms of annual energy. The impact of solar power is analyzed on six different temporal intervals, including hourly and multi-hourly (2- to 6-hour) ramping. The results show how the integration of solar power increases the 1- to 6-hour ramping events of the net load (electric load minus solar power). The study also analyzes the impact of solar power on the distribution of multi-hourly ramping events of fossil-fueled generators and shows increasing 1- to 6-hour ramping events for all different generators. Generators with higher ramp rates such as gas and oil turbine and internal combustion engine generators increased their ramping events by 200% to 280%. For other generator types--including gas combined-cycle generators, coal steam turbine generators, and gas and oil steam turbine generators--more and higher ramping events occurred as well for higher solar power penetration levels.
Analyzing powers for the 3He(rvec p,π+)4He reaction in the region of the Δ1232 resonance
Angular distributions of the analyzing powers have been measured for the 3He(rvec p,π+)4He reaction at proton bombarding energies of 300, 416, and 507 MeV. These results, together with existing measurements at 178, 198, and 800 MeV, provide a comprehensive set of data spanning the region of the Δ1232 resonance. The results are compared with a phenomenological model that incorporates the amplitudes for the pp→dπ+ reaction and calculations from a microscopic (p,π+) model
Proton--proton analyzing power measurements at 16 MeV
Few attempts have been made to measure accurately the proton-proton analyzing powers at low energies. With the advent of polarized particle beams the measurement can now be made with high accuracy. Analyzing powers were measured at nine scattering angles from 100 to 350 in the laboratory system. As a check on systematic errors, analyzing power measurements were also made by scattering protons from 4He. In the p Vector-p case the measured values are in very good agreement with the phase shift predictions. The p Vector-4He measurements, while giving the same form and sign as the phase shift predictions, differ from the predictions by as much as 11 standard deviations. The p Vector-p analyzing powers had a maximum value of -0.0043 +- 0.0004 at 100 (laboratory) and decreased to zero near 250. A new technique to measure analyzing powers without symmetric detectors is explained. This technique preserves the advantages of the symmetric arm method in that current integration, target density, detector efficiencies, and geometry are cancelled from the final expressions. A new scattering chamber, named the Supercube, is described. The Supercube was designed primarily to perform scattering experiments with a polarized beam. It contains both left-right and up-down detectors for use with both spin-1/2 and spin-1 measurements. The Supercube was designed to make analyzing power measurements to an accuracy of 0.001 routine. The Supercube has proved to have low systematic errors and to perform as expected. The systematic errors were found to be equal to or less than 0.0002. (23 figures, 14 tables) (auth)
Time-reversal asymmetry: polarization and analyzing power in nuclear reactions
Measurements of the proton polarization in the reactions 7Li(3He, p vector)9Be and 9Be(3He, p vector)11B and of the analyzing powers in the inverse reactions, initiated by polarized protons at the same center-of-mass energies, show significant differences. This implies the failure of the polarization-analyzing-power theorem and, prima facie, of time-reversal invariance in these reactions. The reaction 2H(3He, p vector)4He and its inverse have also been investigated and show smaller differences. A discussion of instrumental asymmetries is presented
Dalton, Brian H; Power, Geoffrey A; Paturel, Justin R; Rice, Charles L
2015-06-01
The underlying factors related to the divergent findings of age-related fatigue for dynamic tasks are not well understood. The purpose here was to investigate age-related fatigability and recovery between a repeated constrained (isokinetic) and an unconstrained velocity (isotonic) task, in which participants performed fatiguing contractions at the velocity (isokinetic) or resistance (isotonic) corresponding with maximal power. To compare between tasks, isotonic torque-power relationships were constructed prior to and following both fatiguing tasks and during short-term recovery. Contractile properties were recorded from 9 old (~75 years) and 11 young (~25 years) men during three testing sessions. In the first session, maximal power was assessed, and sessions 2 and 3 involved an isokinetic or an isotonic concentric fatigue task performed until maximal power was reduced by 40 %. Compared with young, the older men performed the same number of contractions to task failure for the isokinetic task (~45 contractions), but 20 % fewer for the isotonic task (p < 0.05). Regardless of age and task, maximal voluntary isometric contraction strength, angular velocity, and power were reduced by ~30, ~13, and ~25 %, respectively, immediately following task failure, and only isometric torque was not recovered fully by 10 min. In conclusion, older men are more fatigable than the young when performing a repetitive maximal dynamic task at a relative resistance (isotonic) but not an absolute velocity (isokinetic), corresponding to maximal power. PMID:25943700
Differential cross sections and analyzing powers for the elastic scattering of polarized protons by unpolarized 3He nuclei have been measured at eight energies between 0.3 MeV and 1.0 MeV for scattering angles THETAsub(c.m.) = 52.40-173.30. The cross-section values were normalized to the Rutherford cross section for proton-krypton scattering. The analyzing powers have been measured with a statistical accuracy of about 0.001. The phase-shift analysis based on these data included all phases for orbital angular momenta / <= 1 and the channel-spin mixing parameter for the P waves. An energy parametrization of the phase shifts by an effective-range approximation allowed a simultaneous utilization of all data. (orig.)
Kuharski, Robert A.; Jongeward, Gary A.; Wilcox, Katherine G.; Rankin, Tom R.; Roche, James C.
1991-01-01
The authors review the Environment Power System Analysis Tool (EPSAT) design and demonstrate its capabilities by using it to address some questions that arose in designing the SPEAR III experiment. It is shown that that the rocket body cannot be driven to large positive voltages under the constraints of this experiment. Hence, attempts to measure the effects of a highly positive rocket body in the plasma environment should not be made in this experiment. It is determined that a hollow cathode will need to draw only about 50 mA to ground the rocket body. It is shown that a relatively small amount of gas needs to be released to induce a bulk breakdown near the rocket body, and this gas release should not discharge the sphere. Therefore, the experiment provides an excellent opportunity to study the neutralization of a differential charge.
Analyzing power measurements in πd elastic scattering at 50 MeV
Measurements of the vector analyzing power in πd elastic scattering at 50 MeV are found to agree well with model calculations that include the full πN P11 potential and disagree when this is omitted or suppressed
Unique electron polarimeter analyzing power comparison and precision spin-based energy measurement
Precision measurements of the relative analyzing powers of five electron beam polarimeters, based on Compton, Moller, and Mott scattering, have been performed using the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). A Wien filter in the 100 keV beamline of the injector was used to vary the electron spin orientation exiting the injector. High statistical precision measurements of the scattering asymmetry as a function of the spin orientation were made with each polarimeter. Since each polarimeter receives beam with the same magnitude of polarization, these asymmetry measurements permit a high statistical precision comparison of the relative analyzing powers of the five polarimeters. This is the first time a precise comparison of the analyzing powers of Compton, Moller, and Mott scattering polarimeters has been made. Statistically significant disagreements among the values of the beam polarization calculated from the asymmetry measurements made with each polarimeter reveal either errors in the values of the analyzing power, or failure to correctly include all systematic effects. The measurements reported here represent a first step toward understanding the systematic effects of these electron polarimeters. Such studies are necessary to realize high absolute accuracy (ca. 1%) electron polarization measurements, as required for some parity violation measurements planned at Jefferson Laboratory. Finally, a comparison of the value of the spin orientation exiting the injector that provides maximum longitudinal polarization in each experimental hall leads to an independent and very precise (better than 10-4) absolute measurement of the final electron beam energy
Finite-range DWBA analysis of anomalous analyzing powers in (p, alpha) reactions
Anomalous analyzing powers in reactions Ni(p vector, α)Co(3/2+) are studied in the framework of distorted-waves Born approximation. The anomaly is well reproduced by calculations based on the form factors and spectroscopic amplitudes which are derived from microscopic model wave functions. (author)
Unique electron polarimeter analyzing power comparison and precision spin-based energy measurement
Joseph Grames; Charles Sinclair; Joseph Mitchell; Eugene Chudakov; Howard Fenker; Arne Freyberger; Douglas Higinbotham; B. Poelker; Michael Steigerwald; Michael Tiefenback; Christian Cavata; Stephanie Escoffier; Frederic Marie; Thierry Pussieux; Pascal Vernin; Samuel Danagoulian; Kahanawita Dharmawardane; Renee Fatemi; Kyungseon Joo; Markus Zeier; Viktor Gorbenko; Rakhsha Nasseripour; Brian Raue; Riad Suleiman; Benedikt Zihlmann
2004-03-01
Precision measurements of the relative analyzing powers of five electron beam polarimeters, based on Compton, Moller, and Mott scattering, have been performed using the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). A Wien filter in the 100 keV beamline of the injector was used to vary the electron spin orientation exiting the injector. High statistical precision measurements of the scattering asymmetry as a function of the spin orientation were made with each polarimeter. Since each polarimeter receives beam with the same magnitude of polarization, these asymmetry measurements permit a high statistical precision comparison of the relative analyzing powers of the five polarimeters. This is the first time a precise comparison of the analyzing powers of Compton, Moller, and Mott scattering polarimeters has been made. Statistically significant disagreements among the values of the beam polarization calculated from the asymmetry measurements made with each polarimeter reveal either errors in the values of the analyzing power, or failure to correctly include all systematic effects. The measurements reported here represent a first step toward understanding the systematic effects of these electron polarimeters. Such studies are necessary to realize high absolute accuracy (ca. 1%) electron polarization measurements, as required for some parity violation measurements planned at Jefferson Laboratory. Finally, a comparison of the value of the spin orientation exiting the injector that provides maximum longitudinal polarization in each experimental hall leads to an independent and very precise (better than 10-4) absolute measurement of the final electron beam energy.
Analyzing power measurements in πd elastic scattering at 50 MeV
Measurements of the vector analyzing power in πd elastic scattering at 50 MeV are found to agree well with model calculations that include the full πN P11 potential and disagree when this is omitted or suppressed. (Author) (10 refs., 3 figs.)
First measurement of the vector analyzing power in muon capture by polarized muonic 3He
This paper describes the first measurement of spin observables in nuclear muon capture by 3He. The sensitivity of spin observables to the pseudoscalar coupling is described. The triton asymmetry presented has to be corrected for small systematic effects in order to extract the vector analyzing power. The analysis of these effects is currently underway
We investigate the impact of nonlinear evolution of the gravitational potentials in the ΛCDM model on the integrated Sachs-Wolfe (ISW) contribution to the cosmic microwave background (CMB) temperature power spectrum, and on the cross-power spectrum of the CMB and a set of biased tracers of the mass. We use an ensemble of N-body simulations to directly follow the potentials and compare the results to analytic PT methods. The predictions from the PT match the results to high precision for k-1. We compute the nonlinear corrections to the angular power spectrum and find them to be 100 the departures are more significant; however, the CMB signal is more than a factor 103 larger at this scale. Nonlinear ISW effects therefore play no role in shaping the CMB power spectrum for lm(z)<0.3. Numerical results confirm these expectations and we find no sign change in ISW large-scale structure cross power for low redshifts. Corrections due to nonlinearity and scale dependence of the bias are found to be <10% for l<100, and are therefore below the signal to noise of the current and future measurements. Finally, we estimate the cross-correlation coefficient between the CMB and halos and show that it can be made to match that for the dark matter and CMB to within 5% for thin redshift shells, thus mitigating the need to model bias evolution.
Planck Collaboration; Adam, R.; Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Bartolo, N.; Battaner, E.; Benabed, K.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bracco, A.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chary, R.-R.; Chiang, H. C.; Christensen, P. R.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Zotti, G.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dickinson, C.; Diego, J. M.; Dolag, K.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dunkley, J.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Falgarone, E.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Ghosh, T.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Guillet, V.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Helou, G.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hivon, E.; Hobson, M.; Holmes, W. A.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H.; Jaffe, T. R.; Jewell, J.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Krachmalnicoff, N.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leahy, J. P.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; Mazzotta, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Pearson, T. J.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Pratt, G. W.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Remazeilles, M.; Renault, C.; Renzi, A.; Ricciardi, S.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rouillé d'Orfeuil, B.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Scott, D.; Soler, J. D.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vibert, L.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Watson, R.; Wehus, I. K.; White, M.; White, S. D. M.; Yvon, D.; Zacchei, A.; Zonca, A.
2016-02-01
The polarized thermal emission from diffuse Galactic dust is the main foreground present in measurements of the polarization of the cosmic microwave background (CMB) at frequencies above 100 GHz. In this paper we exploit the uniqueness of the Planck HFI polarization data from 100 to 353 GHz to measure the polarized dust angular power spectra CℓEE and CℓBB over the multipole range 40 <ℓ< 600 well away from the Galactic plane. These measurements will bring new insights into interstellar dust physics and allow a precise determination of the level of contamination for CMB polarization experiments. Despite the non-Gaussian and anisotropic nature of Galactic dust, we show that general statistical properties of the emission can be characterized accurately over large fractions of the sky using angular power spectra. The polarization power spectra of the dust are well described by power laws in multipole, Cℓ ∝ ℓα, with exponents αEE,BB = -2.42 ± 0.02. The amplitudes of the polarization power spectra vary with the average brightness in a way similar to the intensity power spectra. The frequency dependence of the dust polarization spectra is consistent with modified blackbody emission with βd = 1.59 and Td = 19.6 K down to the lowest Planck HFI frequencies. We find a systematic difference between the amplitudes of the Galactic B- and E-modes, CℓBB/CℓEE = 0.5. We verify that these general properties are preserved towards high Galactic latitudes with low dust column densities. We show that even in the faintest dust-emitting regions there are no "clean" windows in the sky where primordial CMB B-mode polarization measurements could be made without subtraction of foreground emission. Finally, we investigate the level of dust polarization in the specific field recently targeted by the BICEP2 experiment. Extrapolation of the Planck 353 GHz data to 150 GHz gives a dust power 𝒟ℓBB ≡ ℓ(ℓ+1)CℓBB/(2π) of 1.32 × 10-2 μKCMB2 over the multipole range
Analyzing powers of the deuteron-proton breakup in a wide phase space region
Deuteron-proton breakup can serve as a very rich testing ground for modern calculations based on model nucleon-nucleon interactions and including also subtle effects of the so-called three-nucleon force (3NF). In the case of experiment exploring a significant part of the phase space, data obtained for continuum of final states constitute a large base for comparisons with theoretical predictions. Moreover, studies with transversally polarized deuterons give access to two vector and three tensor analyzing powers, some of which vanish in the case of the elastic scattering process. A dedicated experiment has been performed at KVI Groningen, with the use of 130 MeV polarized deuteron beam and high acceptance position-sensitive detection system. About 800 data points have been analyzed for each spin observable: vector Ax, Ay and tensor Axx, Axy, Ayy analyzing powers of the 1H(vector (d),pp)n breakup reaction. Theoretical predictions generally describe analyzing power data quite well and the quality of description provided by various approaches is rather similar. There are, however, configurations where the agreement between the data and theory is not so satisfactory. These discrepancies are not always cured by inclusion of 3NF, what indicates incompleteness of the treatment of the spin part of three nucleon system dynamics.
Real time voltage and current phase shift analyzer for power saving applications.
Krejcar, Ondrej; Frischer, Robert
2012-01-01
Nowadays, high importance is given to low energy devices (such as refrigerators, deep-freezers, washing machines, pumps, etc.) that are able to produce reactive power in power lines which can be optimized (reduced). Reactive power is the main component which overloads power lines and brings excessive thermal stress to conductors. If the reactive power is optimized, it can significantly lower the electricity consumption (from 10 to 30%-varies between countries). This paper will examine and discuss the development of a measuring device for analyzing reactive power. However, the main problem is the precise real time measurement of the input and output voltage and current. Such quality measurement is needed to allow adequate action intervention (feedback which reduces or fully compensates reactive power). Several other issues, such as the accuracy and measurement speed, must be examined while designing this device. The price and the size of the final product need to remain low as they are the two important parameters of this solution. PMID:23112662
Jones, W C; Bock, J; Bond, J; Borrill, J; Boscaleri, A; Cabella, P; Contaldi, C; Crill, B; De Bernardis, P; De Gasperis, G; De Oliveira-Costa, A; De Troia, G; Stefano, G D; Hivon, E; Jaffe, A; Kisner, T; Lange, A; MacTavish, C; Masi, S; Mauskopf, P; Melchiorri, A; Montroy, T; Natoli, P; Netterfield, C B; Pascale, E; Piacentini, F; Pogosyan, D; Polenta, G; Prunet, S; Ricciardi, S; Romeo, G; Ruhl, J; Santini, P; Tegmark, M; Veneziani, M; Vittorio, N
2005-01-01
We report on observations of the Cosmic Microwave Background (CMB) obtained during the January 2003 flight of Boomerang . These results are derived from 195 hours of observation with four 145 GHz Polarization Sensitive Bolometer (PSB) pairs, identical in design to the four 143 GHz Planck HFI polarized pixels. The data include 75 hours of observations distributed over 1.84% of the sky with an additional 120 hours concentrated on the central portion of the field, itself representing 0.22% of the full sky. From these data we derive an estimate of the angular power spectrum of temperature fluctuations of the CMB in 24 bands over the multipole range (50 900). As a consistency check, the collaboration has performed two fully independent analyses of the time ordered data, which are found to be in excellent agreement.
Development of a CGE model for analyzing the role of nuclear power in sustainable growth
The purpose of this study is to develop the model for analyzing the role of nuclear power in the sustainable energy supply future of Korea. For the purpose, an energy-economy interaction model of the computational general equilibrium (CGE) approach was developed. The model is a standard optimization model that maximizes the discounted value of Korean economic utility. The model developed in this study can be contributed to setup the national energy policy
Hirai, Shiro
2007-01-01
The effect of the initial condition of inflation on the power spectra of scalar and tensor perturbations is estimated assuming a slow-roll inflation model. By defining a more general initial state in inflation particular properties of the power spectrum such as oscillation can be revealed. The behavior of the power spectrum is shown to exhibit a step-like variation with respect to finite inflation length in cases of both radiation- and scalar matter-dominated pre-inflation. The power spectrum is shown to oscillate in the radiation-dominated case. The effects of such a power spectrum on the TT and TE power spectra are examined for three typical slow-roll inflation models; a small-field model, a large field model, and a hybrid model, considering both pre-inflation models. It is found that the discrepancies between WMAP3 data and the Lambda CDM model, such as suppression of the spectrum at l=2, may be explained to a certain extent by the finite length of inflation for inflation of close to 60 e-folds. The small-...
van Engelen, A; Sehgal, N; Holder, G P; Zahn, O; Nagai, D
2013-01-01
The lensing power spectrum from cosmic microwave background (CMB) temperature maps will be measured with unprecedented precision with upcoming experiments, including upgrades to ACT and SPT. Achieving significant improvements in cosmological parameter constraints, such as percent level errors on sigma_8 and an uncertainty on the total neutrino mass of approximately 50 meV, requires percent level measurements of the CMB lensing power. This necessitates tight control of systematic biases. We study several types of biases to the temperature-based lensing reconstruction signal from foreground sources such as radio and infrared galaxies and the thermal Sunyaev-Zel'dovich effect from galaxy clusters. These foregrounds bias the CMB lensing signal due to their non-Gaussian nature. Using simulations as well as some analytical models we find that these sources can substantially impact the measured signal if left untreated. However, these biases can be brought to the percent level if one masks galaxies with fluxes at 15...
Choudhuri, Samir; Roy, Nirupam; Ghosh, Abhik; Ali, Sk Saiyad
2016-01-01
It is important to correctly subtract point sources from radio-interferometric data in order to measure the power spectrum of diffuse radiation like the Galactic synchrotron or the Epoch of Reionization 21-cm signal. It is computationally very expensive and challenging to image a very large area and accurately subtract all the point sources from the image. The problem is particularly severe at the sidelobes and the outer parts of the main lobe where the antenna response is highly frequency dependent and the calibration also differs from that of the phase center. Here we show that it is possible to overcome this problem by tapering the sky response. Using simulated 150 MHz observations, we demonstrate that it is possible to suppress the contribution due to point sources from the outer parts by using the Tapered Gridded Estimator to measure the angular power spectrum C_l of the sky signal. We also show from the simulation that this method can self-consistently compute the noise bias and accurately subtract it t...
Choudhuri, Samir; Bharadwaj, Somnath; Roy, Nirupam; Ghosh, Abhik; Ali, Sk. Saiyad
2016-06-01
It is important to correctly subtract point sources from radio-interferometric data in order to measure the power spectrum of diffuse radiation like the Galactic synchrotron or the Epoch of Reionization 21-cm signal. It is computationally very expensive and challenging to image a very large area and accurately subtract all the point sources from the image. The problem is particularly severe at the sidelobes and the outer parts of the main lobe where the antenna response is highly frequency dependent and the calibration also differs from that of the phase centre. Here, we show that it is possible to overcome this problem by tapering the sky response. Using simulated 150 MHz observations, we demonstrate that it is possible to suppress the contribution due to point sources from the outer parts by using the Tapered Gridded Estimator to measure the angular power spectrum Cℓ of the sky signal. We also show from the simulation that this method can self-consistently compute the noise bias and accurately subtract it to provide an unbiased estimation of Cℓ.
Adam, R; Aghanim, N; Arnaud, M; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Bartlett, J G; Bartolo, N; Battaner, E; Benabed, K; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bonaldi, A; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Bracco, A; Bucher, M; Burigana, C; Butler, R C; Calabrese, E; Cardoso, J -F; Catalano, A; Challinor, A; Chamballu, A; Chary, R -R; Chiang, H C; Christensen, P R; Clements, D L; Colombi, S; Colombo, L P L; Combet, C; Couchot, F; Coulais, A; Curto, A; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Zotti, G; Delabrouille, J; Delouis, J -M; Désert, F -X; Dickinson, C; Diego, J M; Dolag, K; Dole, H; Donzelli, S; Doré, O; Douspis, M; Ducout, A; Dunkley, J; Dupac, X; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Falgarone, E; Finelli, F; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Frejsel, A; Galeotta, S; Galli, S; Ganga, K; Ghosh, T; Giard, M; Giraud-Héraud, Y; Gjerløw, E; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Gruppuso, A; Guillet, V; Hansen, F K; Hanson, D; Harrison, D L; Helou, G; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hivon, E; Holmes, W A; Huffenberger, K M; Hurier, G; Jaffe, A H; Jaffe, T R; Jewell, J; Jones, W C; Juvela, M; Keihänen, E; Keskitalo, R; Kisner, T S; Kneissl, R; Knoche, J; Knox, L; Krachmalnicoff, N; Kunz, M; Kurki-Suonio, H; Lagache, G; Lamarre, J -M; Lasenby, A; Lattanzi, M; Lawrence, C R; Leahy, J P; Leonardi, R; Lesgourgues, J; Levrier, F; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; Maffei, B; Maino, D; Mandolesi, N; Mangilli, A; Maris, M; Martin, P G; Martínez-González, E; Masi, S; Matarrese, S; Mazzotta, P; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Moss, A; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Netterfield, C B; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; Pagano, L; Pajot, F; Paladini, R; Paoletti, D; Partridge, B; Pasian, F; Patanchon, G; Pearson, T J; Perdereau, O; Perotto, L; Perrotta, F; Pettorino, V; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Popa, L; Pratt, G W; Prunet, S; Puget, J -L; Rachen, J P; Reach, W T; Rebolo, R; Remazeilles, M; Renault, C; Renzi, A; Ricciardi, S; Ristorcelli, I; Rocha, G; Rosset, C; Rossetti, M; Roudier, G; d'Orfeuil, B Rouillé; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Santos, D; Savelainen, M; Savini, G; Scott, D; Soler, J D; Spencer, L D; Stolyarov, V; Stompor, R; Sudiwala, R; Sunyaev, R; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Terenzi, L; Tomasi, M; Tristram, M; Tucci, M; Tuovinen, J; Valenziano, L; Valiviita, J; Van Tent, B; Vibert, L; Vielva, P; Villa, F; Wade, L A; Wandelt, B D; Watson, R; Wehus, I K; White, M; White, S D M; Yvon, D; Zacchei, A; Zonca, A
2016-01-01
The polarized thermal emission from Galactic dust is the main foreground present in measurements of the polarization of the cosmic microwave background (CMB) at frequencies above 100GHz. We exploit the Planck HFI polarization data from 100 to 353GHz to measure the dust angular power spectra $C_\\ell^{EE,BB}$ over the range $40<\\ell<600$. These will bring new insights into interstellar dust physics and a precise determination of the level of contamination for CMB polarization experiments. We show that statistical properties of the emission can be characterized over large fractions of the sky using $C_\\ell$. For the dust, they are well described by power laws in $\\ell$ with exponents $\\alpha^{EE,BB}=-2.42\\pm0.02$. The amplitudes of the polarization $C_\\ell$ vary with the average brightness in a way similar to the intensity ones. The dust polarization frequency dependence is consistent with modified blackbody emission with $\\beta_d=1.59$ and $T_d=19.6$K. We find a systematic ratio between the amplitudes of ...
The lensing power spectrum from cosmic microwave background (CMB) temperature maps will be measured with unprecedented precision with upcoming experiments, including upgrades to the Atacama Cosmology Telescope and the South Pole Telescope. Achieving significant improvements in cosmological parameter constraints, such as percent level errors on σ8 and an uncertainty on the total neutrino mass of ∼50 meV, requires percent level measurements of the CMB lensing power. This necessitates tight control of systematic biases. We study several types of biases to the temperature-based lensing reconstruction signal from foreground sources such as radio and infrared galaxies and the thermal Sunyaev-Zel'dovich effect from galaxy clusters. These foregrounds bias the CMB lensing signal due to their non-Gaussian nature. Using simulations as well as some analytical models we find that these sources can substantially impact the measured signal if left untreated. However, these biases can be brought to the percent level if one masks galaxies with fluxes at 150 GHz above 1 mJy and galaxy clusters with masses above M vir = 1014 M ☉. To achieve such percent level bias, we find that only modes up to a maximum multipole of l max ∼ 2500 should be included in the lensing reconstruction. We also discuss ways to minimize additional bias induced by such aggressive foreground masking by, for example, exploring a two-step masking and in-painting algorithm.
Van Engelen, A.; Sehgal, N. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States); Bhattacharya, S. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Holder, G. P. [Department of Physics, McGill University, 3600 Rue University, Montreal, Quebec H3A 2T8 (Canada); Zahn, O. [Berkeley Center for Cosmological Physics, Department of Physics, University of California, and Lawrence Berkeley National Labs, Berkeley, CA 94720 (United States); Nagai, D. [Department of Physics, Department of Astronomy and Yale Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06520 (United States)
2014-05-01
The lensing power spectrum from cosmic microwave background (CMB) temperature maps will be measured with unprecedented precision with upcoming experiments, including upgrades to the Atacama Cosmology Telescope and the South Pole Telescope. Achieving significant improvements in cosmological parameter constraints, such as percent level errors on σ{sub 8} and an uncertainty on the total neutrino mass of ∼50 meV, requires percent level measurements of the CMB lensing power. This necessitates tight control of systematic biases. We study several types of biases to the temperature-based lensing reconstruction signal from foreground sources such as radio and infrared galaxies and the thermal Sunyaev-Zel'dovich effect from galaxy clusters. These foregrounds bias the CMB lensing signal due to their non-Gaussian nature. Using simulations as well as some analytical models we find that these sources can substantially impact the measured signal if left untreated. However, these biases can be brought to the percent level if one masks galaxies with fluxes at 150 GHz above 1 mJy and galaxy clusters with masses above M {sub vir} = 10{sup 14} M {sub ☉}. To achieve such percent level bias, we find that only modes up to a maximum multipole of l {sub max} ∼ 2500 should be included in the lensing reconstruction. We also discuss ways to minimize additional bias induced by such aggressive foreground masking by, for example, exploring a two-step masking and in-painting algorithm.
Steyn G.F.
2012-12-01
Full Text Available This project looks at the angular distributions of the differential cross sections and analyzing powers of a few low lying states of 56Co in the reaction 58Ni(p,3He56Co at three different incident energies between 80and 120 MeV. The measurements are compared with zero-range distorted-wave Born approximation (DWBA calculations in which we assume a simple direct two-nucleon pickup process. Earlier inclusive (p,3He reaction studies on similar targets were successfully treated in terms of a statistical pre-equilibrium multistep formalism, in which the final stage of the reaction involved a deuteron pickup, described by means of the DWBA. The analyzing power was shown to be rather sensitive to the contributions of the different order steps. However some features observed in the analyzing powers of these inclusive studies, though reproduced by the theory, are not fully understood.We therefore investigate the ability of the DWBA model to describe the (p,3He pickup reaction to discrete states at different incident energies using a high resolution spectrometer.
Tensor Analyzing Powers for Quasi-Elastic Electron Scattering from Deuterium
Z.-L. Zhou; M. Bouwhuis; M. Ferro-Luzzi; E. Passchier; R. Alarcon; M. Anghinolfi; H. Arenhoevel; R. van Bommel; T. Botto; J.F.J. van den Brand; H.J. Bulten; S. Choi; J. Comfort; S.M. Dolfini; R. Ent; C. Gaulard; D.W. Higinbotham; C.W. de Ja ger; E. Konstantinov; J. Lang; W. Leidemann; D.J. de Lange; M.A. Miller; D. Niko lenko; N. Papadakis; I. Passchier; H.R. Poolman; S.G. Popov; I. Rachek; M. Ripan i; E. Six; J.J.M. Steijger; M. Taiuti; O. Unal; N. Vodinas; H. de Vries
1999-01-01
We report on a first measurement of tensor analyzing powers in quasi-elastic electron-deuteron scattering at an average three-momentum transfer of 1.7 fm{sup -1}. Data sensitive to the spin-dependent nucleon density in the deuteron were obtained for missing momenta up to 150 MeV/c with a tensor polarized {sup 2}H target internal to an electron storage ring. The data are well described by a calculation that includes the effects of final-state interaction, meson-exchange and isobar currents, and leading-order relativistic contributions.
The tensor analyzing power Asub(yy) near s-wave levels
In the neighborhood of an isolated resonance induced by s-wave particles, the component Asub(yy)(theta) of the tensor analyzing power is independent of the reaction angle theta. The constant value of Asub(yy)(theta) is a function of the level spin J and of the (l',s') configuration in the exit channel of the resonant amplitude. The use of this fact as a diagnostic tool in an analysis of the process is discussed and demonstrated with data available. It is also pointed out that efficient polarimeters can be constructed, which measure the quantity Asub(yy). (Auth.)
In this paper, experimental results are presented for the spatial and energy distributions of charge-discriminated Sn ions ejected from laser-produced plasmas. The plasmas were formed on solid, planar Sn targets, irradiated with a Nd:YAG laser. Ions were investigated using a calibrated electrostatic sector analyzer, scanning an energy-to-charge ratio range of 0.22 to 2.2 keV/e for emission angles between 20 and 80 degrees relative to target normal. Results were obtained for three laser power densities, in the region suitable for inducing significant extreme ultraviolet emission, of the order 1.5-8.1 x 1011 W/cm2. The fully differentiated data were found to be well characterized by Gaussian fits, which allowed trends in the emission profiles to be readily quantified. Ions of set energy and charge were observed to possess a preferential angle of emission, the superposition of which yields a physical basis for the total angular emission observed previously and in this work. The experimental results obtained have been related to physical processes within the plasma that influence the energy and angle of ejection of ions from laser produced plasmas.
Maeda, Y; Ishida, T; Kacharava, A; Nomachi, M; Shimbara, Y; Sugaya, Y; Tamura, K; Yagita, T; Yasuda, K; Yoshida, H P; Wilkin, C
2008-01-01
The differential cross section and analyzing power $A_y$ of the ${\\vec p}p{\\to}pp{\\pi}^0$ reaction have been measured at RCNP in coplanar geometry at a beam energy of 390 MeV and the dependence on both the pion emission angle and the relative momentum of the final protons have been extracted. The angular variation of Ay for the large values of the relative momentum studied here shows that this is primarily an effect of the interference of pion s- and p-waves and this interference can also explain the momentum dependence. Within the framework of a very simple model, these results would suggest that the pion-production operator has a significant long-range component.
Hawkins, D
1994-03-01
A computer program was developed in conjunction with a musculoskeletal modeling scheme to determine lower extremity joint angular velocity profiles which allow specific muscles, if activated tetanically, to generate their greatest power. As input the program requires subject anthropometric and joint configuration data. Muscle-tendon (MT) attachment location data and a straight line MT model are used to calculate MT lengths for each joint configuration. The shortening velocity which allows an active muscle to generate its greatest power is calculated based on muscle architecture and a relationship between power and shortening velocity. A finite difference technique is used to calculate the time between sequential joint configurations which will produce the optimal muscle shortening velocity. This time is then used to calculate optimal joint angular velocities for each muscle and and for each joint configuration. The utility of this program is demonstrated by calculating optimal joint angular velocities for fifteen muscles and comparing calculated knee extension velocities with experimental results cited in the literature. PMID:8062553
... A This image displays a frequent location for candida infection (angular cheilitis), the corners of the mouth. Overview ... infection, those affected may also have thrush (oral candidiasis). The areas are generally slightly painful. The condition ...
MEASUREMENT OF THE ANALYZING POWER IN PP ELASTIC SCATTERING IN THE PEAK CNI REGION AT RHIC.
MAKDISI,Y.; OKADA,H.; ALEKSEEV,I.G.; BRAVAR,A.; BUNCE,G.; ET AL
2005-01-28
The analyzing power A{sub N} for pp elastic scattering is expected to reach a peak value of 0.045 in the Coulomb Nuclear Interference (CNI) region at a momentum transfer -t of 0.003 (GeV/c){sup 2}. During the 2004 RHIC Run, we completed a measurement of A{sub N} in the CNI region by detecting the recoil protons from pp elastic scattering using a polarized atomic hydrogen gas jet target and the 100 GeV RHIC proton beam. We report the first measurements of the A{sub N} absolute value and shape in the -t range from 0.0015 to 0.010 (GeV/c){sup 2} with a precision better than 0.005 for each A{sub N} data point. The recoil protons were detected with two arrays of Si detectors. The absolute target polarization as monitored by a Breit-Rabi polarimeter was stable at 0.924 {+-} 0.018. This result allows us to further investigate the spin dependence of elastic pp scattering in the very low -t region.
Analyzing power in CNI-region at AGS (experiment E950)
Acceleration of polarized protons is one of the exciting features of the new Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. Measurements of beam polarization are required both for experiments and the accelerator tuning. Elastic scattering in the Coulomb nuclear interference (CNI) region of polarized proton beams on a carbon target demonstrates asymmetry which can be used to build a polarimeter. The methods proposed for a RHIC CNI polarimeter were tested with the AGS polarized beam in the E950 experiment. A 21.7 GeV/c polarized proton beam was scattered on an extremely thin carbon ribbon target located in the AGS ring. Two symmetrical arms consisting of silicon strip detectors (SSD) and a micro channel plate (MCP) were used to identify recoil carbon. Data obtained demonstrates a good identification of the reaction by the apparatus and a significant analyzing power. A RHIC polarimeter setup with 4 SSDs but without MCPs will be used to commission RHIC with polarized protons and for the first spin physics running in 2001
Analyzing power of AGATA triple clusters for gamma-ray linear polarization
Bizzeti, P.G.; Sona, P.; Melon, B.; Bizzeti-Sona, A.M.; Perego, A. [Universita di Firenze, Dipartimento di Fisica, Firenze (Italy); INFN, Firenze (Italy); Michelagnoli, C.; Lunardi, S.; Mengoni, D.; Recchia, F. [INFN, Padova (Italy); Universita di Padova, Dipartimento di Fisica, Padova (Italy); Bazzacco, D.; Farnea, E.; Menegazzo, R.; Ur, C.A. [INFN, Padova (Italy); De Angelis, G.; Gottardo, A.; Napoli, D.R.; Sahin, E.; Valiente-Dobon, J.J. [Laboratori Nazionali di Legnaro, INFN, Padova (Italy); Gadea, A. [University of Valencia, IFIC, CSIC, Valencia (Spain); Nannini, A. [INFN, Firenze (Italy)
2015-04-01
We have investigated the ability of AGATA triple clusters to measure the linear polarization of gamma rays, exploiting the azimuthal-angle dependence of the Compton scattering differential cross section. To this aim, partially polarized gamma rays have been produced by Coulomb excitation of the first excited state of {sup 104}Pd and {sup 108}Pd, which decay to the ground state by emission of gamma rays of 555.8 keV and 433.9 keV, respectively. Pulse-shape analysis and gamma-ray tracking techniques have been used to determine the position and time sequence of the interaction points inside the germanium crystals. Anisotropies in the detection efficiency have been taken into account using 661.6 keV gammas from a {sup 137}Cs radioactive source. We obtain an average analyzing power of 0.451(34) at 433.9 keV and 0.484(24) at 555.8 keV. (orig.)
Analyzing Thermal Module Developments and Trends in High-Power LED
Jung-Chang Wang
2014-01-01
Full Text Available The solid-state light emitting diode (SSLED has been verified as consumer-electronic products and attracts attention to indoor and outdoor lighting lamp, which has a great benefit in saving energy and environmental protection. However, LED junction temperature will influence the luminous efficiency, spectral color, life cycle, and stability. This study utilizes thermal performance experiments with the illumination-analysis method and window program (vapour chamber thermal module, VCTM V1.0 to investigate and analyze the high-power LED (Hi-LED lighting thermal module, in order to achieve the best solution of the fin parameters under the natural convection. The computing core of the VCTM program employs the theoretical thermal resistance analytical approach with iterative convergence stated in this study to obtain a numerical solution. Results showed that the best geometry of thermal module is 4.4 mm fin thickness, 9.4 mm fin pitch, and 37 mm fin height with the LED junction temperature of 58.8°C. And the experimental thermal resistances are in good agreement with the theoretical thermal resistances; calculating error between measured data and simulation results is no more than ±7%. Thus, the Hi-LED illumination lamp has high life cycle and reliability.
Corona Bellostas, Blanca; Ruiz, Diego; San Miguel Alfaro, Guillermo
2016-01-01
Concentrating Solar Power (CSP) technology is developing in order to achieve higher energy efficiency, reduced economic costs, and improved firmness and dispatchability in the generation of power on demand. To this purpose, a research project titled HYSOL has developed a new power plant, consisting of a combined cycle configuration with a 100 MWe steam turbine and an 80 MWe gas-fed turbine with biomethane. Technological developments must be supported by the identification, quantification, and...
Chenine, Moustafa
2013-01-01
The strain on modern electrical power systems has led to an ever-increasing utilization of new information and communication technologies (ICT) to improve their efficiency and reliability. Wide area monitoring and control (WAMC) systems offer many opportunities to improve the real-time situational awareness in the power system. These systems are essen-tially SCADA systems but with continuous streaming of measurement data from the power system. The quality of WAMC systems and the applications ...
Modeling and analyzing of nuclear power peer review on enterprise operational efficiency
无
2006-01-01
Based on the practice and analysis of peer review in nuclear power plants, the models on the Pareto improvement of peer review, governance entropy decrease of peer review are set up and discussed. The result shows that the peer review of nuclear power is actually a process of Pareto improvement, and of governance entropy decrease. It's a process of improvement of the enterprise operational efficiency accordingly.
Analyzing the effects of component reliability on naval integrated power system quality of service
Hawbaker, Benjamin F.
2008-01-01
CIVINS The Integrated Power System (IPS) is a key enabling technology for future naval vessels and their advanced weapon systems. While conventional warship designs utilize separate power systems for propulsion and shipboard electrical service, the IPS combines these functions. This allows greater optimization of engineering plant design and operations and leads to significant potential lifecycle cost savings through reduced fuel consumption and maintenance. Traditionally the focus of powe...
The European Union aims to reduce greenhouse gas emissions by 80–95% in 2050 compared to 1990 levels. The transition towards a low-carbon economy implies the almost complete decarbonization of Europe's power sector, which could be achieved along various pathways. In this paper, we evaluate the economic implications of alternative energy policies for Europe's power sector by applying a linear dynamic electricity system optimization model in over 36 scenarios. We find that the costs of decarbonizing Europe's power sector by 2050 vary between 139 and 633 bn €2010, which corresponds to an increase of between 11% and 44% compared to the total system costs when no CO2 reduction targets are implemented. In line with economic theory, the decarbonization of Europe's power sector is achieved at minimal costs under a stand-alone CO2 reduction target, which ensures competition between all low-carbon technologies. If, however, renewable energies are exempted from competition via supplementary renewable energy (RES-E) targets or if investments in new nuclear and CCS power plants are politically restricted, the costs of decarbonization significantly rise. Moreover, we find that the excess costs of supplementary RES-E targets depend on the acceptance of alternative low carbon technologies. For example, given a complete nuclear phase-out in Europe by 2050 and politically implemented restrictions on the application of CCS to conventional power plants, supplementary RES-E targets are redundant. While in such a scenario the overall costs of decarbonization are comparatively high, the excess costs of supplementary RES-E targets are close to zero. - Highlights: • We evaluate the economic implications of alternative energy policies for Europe's power sector. • Total decarbonization costs vary between 139 and 633 billion €2010 up to 2050. • Decarbonization at minimal costs is ensured by competition between all low carbon technologies. • Excess costs of supplementary
Piacentini, F; Bock, J; Bond, J; Borrill, J; Boscaleri, A; Cabella, P; Contaldi, C; Crill, B; De Bernardis, P; De Gasperis, G; De Oliveira-Costa, A; De Troia, G; Stefano, G D; Hivon, E; Jaffe, A; Kisner, T; Jones, W; Lange, A; Masi, S; Mauskopf, P; MacTavish, C; Melchiorri, A; Montroy, T; Natoli, P; Netterfield, C B; Pascale, E; Pogosyan, D; Polenta, G; Prunet, S; Ricciardi, S; Romeo, G; Ruhl, J; Santini, P; Tegmark, M; Veneziani, M; Vittorio, N
2005-01-01
We present a measurement of the temperature-polarization angular cross power spectrum, , of the Cosmic Microwave Background. The result is based on $\\sim 200$ hours of data from 8 polarization sensitive bolometers operating at 145 GHz during the 2003 flight of BOOMERANG. We detect a significant correlation in the $\\ell$-range between 50 and 950 with a statistical significance > 3.5 sigma. Contamination by polarized foreground emission and systematic effects are negligible in comparison with statistical uncertainty. The spectrum is consistent with previous detections and with the "concordance model" that assumes adiabatic initial conditions. This is the first measurement of using bolometric detectors.
Analyze and Improve Lifetime in 3L-NPC Inverter from Power Cycle and Thermal Balance
Chen, Quan; Chen, Zhe; Wang, Qunjing;
2014-01-01
load voltage is applied to reduce power cycle and switching losses. And then, three-level active neutral point-clamped topology is taken into account to wake the most thermo stressed device. In order to validate the improve lifetime method in this paper, a 2MW 3L-NPC converter used in wind energy has......Three-level Neutral-point-clamped (3L-NPC) topology is becoming a realistic alternative to the conventional one in high-voltage and high-power application. Studies show that the power cycling mean time to failure (MTTF) of the semiconductor bond wire in 3L-NPC inverter system may be very short...
Meintz, Andrew; Gonder, Jeffrey; Jorgenson, Jennie; Brooker, Aaron
2016-08-01
This work examines the grid impact of in-motion roadway wireless power transfer through the examination of the electrification of high-capacity roadways inside a metropolitan area. The work uses data from a regional travel study and the Federal Highway Administration's Highway Performance Monitoring System to estimate the electrified roadway's hourly power use throughout a week. The data are then combined with hourly grid load estimates for the same metropolitan area to determine the overlay of traditional grid load with additional load from a future electrified roadway.
Fuel-Cell-Powered Electric Motor Drive Analyzed for a Large Airplane
Brown, Gerald V.; Choi, Benjamin B.
2005-01-01
Because of its high efficiency, fuel cell technology may be used to launch a new generation of more-electric aeropropulsion and power systems for future aircraft. Electric-motor-driven airplanes using fuel-cell powerplants would be beneficial to the environment because of fuel savings, low noise, and zero carbon-dioxide emissions. In spite of the fuel cell s efficiency benefit, to produce the same shaft drive power, a fuel cell- powered electric-drive system must be definitely heavier than a turbine-drive system. However, the fuel-cell system s overall efficiency from fuel-to-shaft power is higher than for a turbine-drive system. This means that the fuel consumption rate could be lower than for a conventional system. For heavier, fuel-laden planes for longer flights, we might achieve substantial fuel savings. In the airplane industry, in fact, an efficiency gain of even a few percentage points can make a major economic difference in operating costs.
Implementation of HRM practices is often devolved from the HRM unit to front line managers and supervisors. However, the implementation of these practices by line managers and supervisors may vary significantly. They may, for example, be unaware of how to implement HRM practices or sceptical towards the effectiveness of the intended practices. Based on the literature, interviews and workshops in the nuclear power industry, a self-assessment method of HRM practices for intra-organizational use was developed. The assessment method was piloted in four nuclear power organizations. The assessment method seems to be a good tool for generating fruitful discussion on HRM practices, finding areas of HRM practices that need to be developed, and triggering peer-to-peer knowledge sharing and learning on HRM practices.
Maeki, Eerikki [Aalto Univ. (Finland). Dept. of Industrial Engineering and Management; Pahkin, Krista; Lindstroem, S.; Kurki, Anna-Leena [Finnish Institue of Occupational Health, Helsinki (Finland). Centre of Expertise for the Development of Work and Organizations
2015-04-15
Implementation of HRM practices is often devolved from the HRM unit to front line managers and supervisors. However, the implementation of these practices by line managers and supervisors may vary significantly. They may, for example, be unaware of how to implement HRM practices or sceptical towards the effectiveness of the intended practices. Based on the literature, interviews and workshops in the nuclear power industry, a self-assessment method of HRM practices for intra-organizational use was developed. The assessment method was piloted in four nuclear power organizations. The assessment method seems to be a good tool for generating fruitful discussion on HRM practices, finding areas of HRM practices that need to be developed, and triggering peer-to-peer knowledge sharing and learning on HRM practices.
Analyzing the Impacts of Increased Wind Power on Generation Revenue Sufficiency: Preprint
Wang, Qin; Wu, Hongyu; Tan, Jin; Hodge, Bri-Mathias; Li, Wanning; Luo, Cheng
2016-08-01
The Revenue Sufficiency Guarantee (RSG), as part of make-whole (or uplift) payments in electricity markets, is designed to recover the generation resources' offer-based production costs that are not otherwise covered by their market revenues. Increased penetrations of wind power will bring significant impacts to the RSG payments in the markets. However, literature related to this topic is sparse. This paper first reviews the industrial practices of implementing RSG in major U.S. independent system operators (ISOs) and regional transmission operators (RTOs) and then develops a general RSG calculation method. Finally, an 18-bus test system is adopted to demonstrate the impacts of increased wind power on RSG payments.
Implementation of HRM practices is often devolved from the HRM unit to front line managers and supervisors. However, the implementation of these practices by line managers and supervisors may vary significantly. They may, for example, be unaware of how to implement HRM practices or skeptical towards the effectiveness of the intended practices. Based on the literature, interviews and workshops in the nuclear power industry, a self-assessment method of HRM practices for intra-organizational use was developed. The assessment method was piloted in four nuclear power organizations. The assessment method seems to be a good tool for generating fruitful discussion on HRM practices, finding areas of HRM practices that need to be developed, and triggering peer-to-peer knowledge sharing and learning on HRM practices. (authors)
Analyzing the power of classes in an object-oriented software system
Wang, Muchou
2011-10-01
Power of a class reflects the relative importance of the class in an object-oriented software system, and has many implications for resource allocating. And how to measure it is still a problem we face. They paper presents to measure it based the connection structure of a network constructed from the software. To support this, we first use a network model to describe the connection structure. Then some centrality metrics used in social network analysis are introduced to quantify the power of classes. The commons and differences among these centrality metrics are revealed. We think these metrics can be used together to have a more systematic view of the importance of each class.
THE ANGULAR POWER SPECTRUM OF DUST-OBSCURED GALAXIES AND ITS IMPACT ON SUNYAEV ZEL'DOVICH STUDIES
A. A. Montaña
2011-01-01
Full Text Available En este trabajo medimos el espectro angular de potencias de la población de galaxias milimétricas (SMGs a partir de observaciones a 1.1 mm realizadas con la cámara AzTEC en el Atacama Submillimeter Telescope Experiment (ASTE y el James Clerk Maxwell Telecope (JCMT. La muestra de campos observados nos permite comparar el espectro angular de potencias de las SMGs medido en la dirección de regiones del Universo sin sesgo y otras sobre densas. Nuestras mediciones permiten acotar el impacto que tiene la población de SMGs en mediciones del espectro de potencias de las fluctuaciones primarias y secundarias del fondo cósmico de radiación de microndas (CMB, que actualmente están siendo medidas por una nueva generación de experimentos con resoluciones espaciales del orden de minutos de arco y que operan a longitudes de onda milimétricas.
A new solid angle detector, SPESO-2π, has been constructed in order to obtain clear data for this reaction. It consists mainly of 24 lead glass bars, arranged vertically in two shells around the liquid hydrogen target. A circle of scintillators vetoes charged particles. The bars serve as Cerenkov counters. A new fast topological trigger was developed which rapidly separates good configurations of two photon hits from background. A simulation code was set up that offered the opportunity to create pion events according to several theoretical models. The combination of measured values and simulation calculation provided the final results. The total cross sections follow exactly the established excitation function, but with much smaller error bars. No indication for a narrow dibaryon resonance with M=2121 MeV has been found. The differential cross sections were established over half of the angular range and the analyzing power has been measured for the first time in such a systematic way. The comparison with neutron-proton scattering with charged pion production reveals the existence of a non negligible partial cross section below 600 MeV
Blanca Corona
2016-05-01
Full Text Available Concentrating Solar Power (CSP technology is developing in order to achieve higher energy efficiency, reduced economic costs, and improved firmness and dispatchability in the generation of power on demand. To this purpose, a research project titled HYSOL has developed a new power plant, consisting of a combined cycle configuration with a 100 MWe steam turbine and an 80 MWe gas-fed turbine with biomethane. Technological developments must be supported by the identification, quantification, and evaluation of the environmental impacts produced. The aim of this paper is to evaluate the environmental performance of a CSP plant based on HYSOL technology using a Life Cycle Assessment (LCA methodology while considering different locations. The scenarios investigated include different geographic locations (Spain, Chile, Kingdom of Saudi Arabia, Mexico, and South Africa, an alternative modelling procedure for biomethane, and the use of natural gas as an alternative fuel. Results indicate that the geographic location has a significant influence on the environmental profile of the HYSOL CSP plant. The results obtained for the HYSOL configuration located in different countries presented significant differences (between 35% and 43%, depending on the category, especially in climate change and water stress categories. The differences are mainly attributable to the local availability of solar and water resources and composition of the national electricity mix. In addition, HYSOL technology performs significantly better when hybridizing with biomethane instead of natural gas. This evidence is particularly relevant in the climate change category, where biomethane hybridization emits 27.9–45.9 kg CO2 eq per MWh (depending on the biomethane modelling scenario and natural gas scenario emits 264 kg CO2 eq/MWh.
Analyzing the decision making process of certifying digital control systems of nuclear power plants
Highlights: ► We have performed basic research in analyzing certification process and developed a regulatory decision making model for nuclear digital control system certification. The model views certification as an evidence–confidence conversion process. ► We have applied this model to analyze previous nuclear digital I and C certification experiences and obtained valuable insights. ► Furthermore, a prototype of a computer-aided licensing support system based on the model has been developed to enhance regulatory review efficiency. - Abstract: Safety-critical computing systems need regulators’ approval before operation. Such a permit issue process is called “certification”. Digital instrumentation and Control (I and C) certification in the nuclear domain has always been problematic and lengthy. Thus, the certification efficiency has always been a crucial concern to the applicant whose business depends on the regulatory decision. However, to our knowledge, there is little basic research on this topic. This study presents a Regulatory Decision-Making Model aiming at analyzing the characteristics and efficiency influence factors in a generic certification process. This model is developed from a dynamic operational perspective by viewing the certification process as an evidence–confidence conversion process. The proposed model is then applied to previous nuclear digital I and C certification experiences to successfully explain why some cases were successful and some were troublesome. Lessons learned from these cases provide invaluable insights regarding to the regulatory review activity. Furthermore, to utilize the insights obtained from the model, a prototype of a computer-aided licensing support system has been developed to speed up review evidence preparation and manipulation; thus, regulatory review efficiency can be further improved.
A matrix game model for analyzing FTR bidding strategies in deregulated electric power markets
Suppliers in deregulated electric power markets compete for financial transmission rights (FTRs) to hedge against congestion charges. The system operator receives the bids for FTRs submitted by the suppliers and develops an allocation strategy by solving an optimization model. Each FTR bid is defined by a path, a quantity indicating the amount of FTRs the supplier is bidding for in that path, and the price that the supplier is willing to pay for each FTR. The FTR revenue is calculated only after the electricity market has been cleared by computing the differences in the LMPs at the pair of nodes that connect each path. Thus, suppliers rely on forecasts of locational marginal prices (LMPs) to develop their FTR bids. In this paper, we present a game theoretic modeling approach to develop FTR bidding strategies for power suppliers assuming that they have forecasts of LMPs. The game theoretic model considers multiple participants as well as network contingencies. We apply the game theoretic model on a sample network to assess impacts of variations of bid and network parameters on the FTR market outcome. (author)
Development of the nuclear plant analyzer for Korean standard Nuclear Power Plants
Kim, Shin Hwan; Kim, Hyeong Heon; Song, In Ho; Hong, Eon Yeong; Oh, Yeong Taek [Korea Power Engineering Company Inc., Yongin (Korea, Republic of)
2000-12-15
The purpose of this study is to develop an NPA for the Ulchin Nuclear Power Plant Unit 3 and 4, the first KSNP type plant. In this study, the process model simulating the overall plant systems, GUI and simulation executive which provide the functions of an engineering simulator were developed, and the NPA was completed by integrating them. The contents and the scope of this study are as follows : main feedwater system, auxiliary feedwater system, Chemical and Volume Control System(CVCS), Safety Injection System(SIS), Shutdown Cooling System(SCS), electric power supply system, Core Protection Calculator(CPC), various plant control system, development of the graphics screens for each system, real-time simulation, simulation control for the enhancement of functional capabilities, user friendly GUI, collection of the design and operating data, establishment of the NPA database, integration of the GUI and simulation control program with process model, collection of the data for the verification and validation of the developed NPA, collection of the plant test data, collection and review of the results of other computer codes, verification of the simulation accuracy by comparing the NPA results with the actual plant data, validation of the simulation capability of the NPA, comparison against available data from other analysis suing different computer codes.
The analysis of linear static behavior of folded-plate structures like the turbine building of a nuclear power plant by the Finite Element Method. Folded-plate isoparametric plane elements with 48 degrees of freedom each, 8 nodal points, in which shear deformations are considered, and super-elements, whose internal degrees of freedom are condensated, are used. Arbitrary shells can be analized too. A brief exposition of the method is present and the developing of the foregoing element and super-element is also shown. A computer program was developed for the CDC-CYBER 175 computer machine and the FORTRAN IV language was used. The coeficients of the equations system are stored by the technique of block partitioning with a compacted column storage scheme and special attention was dedicated to the preparation of the problem's data and some options were developed for this purpose. (Author)
Communications among MCR operators is an important factor for understanding how and how well MCR operators manage abnormal situations in NPPs. As mentioned by Ujita et al., the performance of MCR operators in emergency situations in NPPs is strongly affected by not only the cognitive process for each operator, but also by communications and collaboration among operators. Many researches have been conducted to find out the relation between the communication of human operators and the performance of them. But, it seems that few researches have been conducted on in what way the communication among MCR operators should be performed to enhance the performance of them. In this paper, we propose an analysis method for evaluating the quality of communications among MCR operators in nuclear power plants (NPPs)
Angular momentum in subbarrier fusion
We have measured the ratio of the isomer to ground-state yields of 137Ce produced in the fusion reactions 128Te(12C,3n), 133Cs(7Li,3n), 136Ba(3He,2n), 136Ba(4He,3n), and 137Ba(3He,3n), from energies above the Coulomb barrier to energies typically 20--30% below the barrier by observing the delayed x- and γ-ray emission. We deduce the average angular momentum, , from the measured isomer ratios with a statistical model. In the first three reactions we observe that the values of exhibit the behavior predicted for low energies and the expected variation with the reduced mass of the entrance channel. We analyze these data and the associated cross sections with a barrier penetration model that includes the coupling of inelastic channels. Measurements of average angular momenta and cross sections made on other systems using the γ-multiplicity and fission-fragment angular correlation techniques are then analyzed in a similar way with this model. The discrepancies with theory for the γ-multiplicity data show correlations in cross section and angular momentum that suggest a valid model can be found. The measurements of angular momentum using the fission fragment angular correlation technique, however, do not appear reconcilable with the energy dependence of the cross sections. This systematic overview suggests, in particular, that our current understanding of the relationship of angular momentum and anisotropy in fission fragment angular correlations is incomplete. 26 refs
Methods for Analyzing the Economic Value of Concentrating Solar Power with Thermal Energy Storage
Denholm, Paul [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Miller, Mackay [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhou, Ella [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wang, Caixia [State Grid Energy Research Inst., Beijing (China)
2015-07-20
Concentrating solar power with thermal energy storage (CSP-TES) provides multiple quantifiable benefits compared to CSP without storage or to solar photovoltaic (PV) technology, including higher energy value, ancillary services value, and capacity value. This report describes modeling approaches to quantifying these benefits that have emerged through state-level policymaking in the United States as well as the potential applicability of these methods in China. The technical potential for CSP-TES in China is significant, but deployment has not yet achieved the targets established by the Chinese government. According to the 12th Five Year Plan for Renewable Energy (2011-2015), CSP was expected to reach 1 GW by 2015 and 3 GW by 2020 in China, yet as of December 2014, deployment totaled only 13.8 MW. One barrier to more rapid deployment is the lack of an incentive specific to CSP, such as a feed-in tariff. The 13th Five Year Plan for Solar Generation (2016-2020), which is under development, presents an opportunity to establish a feed-in tariff specific to CSP. This report, produced under the auspices of the U.S.-China Renewable Energy Partnership, aims to support the development of Chinese incentives that advance CSP deployment goals.
Malinina, L V; Augustyniak, W; Boivin, M; Boyard, J L; Dahl, R; Drews, M; Ellegaard, C; Fahri, L; Gaarde, C; Hennino, T; Jourdain, J C; Kagarlis, M A; Kravtsov, A V; Künne, R A; Larsen, J C; Morsch, P; Mylnikov, V A; Orichtchin, E M; Perdrisat, C F; Piskunov, N M; Prokofiev, A N; Punjabi, V; Radvanyi, P; Ramstein, B; Razmyslovich, B V; Roy-Stephan, M; Sitnik, I M; Skousen, M; Strokovsky, E A; Tkach, I I; Tomasi-Gustafsson, E; Volkov, S S; Zhdanov, A A; Zupranski, P
2001-01-01
A study of inelastic scattering of polarized 3.73 GeV/c deuterons on protons in the energy region of the Roper N*(1440) and the {DELTA}(1232) resonances excitation has been performed in an exclusive experiment at LNS (Laboratoire National SATURNE, Saclay, France) using the SPES-{pi} setup.Tensor and vector analyzing powers of pion production for the reactions d + p {\\to} d + n + pi^{+}, d + p {\\to} d + p + pi^{0}, d + p {\\to} d + N + pi pi have been measured as functions of the squared deuteron 4-momentum transfer t, of the effective mass of the subsystems (N pi), (N pi pi) and of the pion emission angle. A strong dependence of these analyzing powers upon the pion emission angle is observed. It is found that A_{yy} values for the considered reaction channels are systematically larger than the known inclusive {p (d, d {\\prime}) X} world data at the nearest beam energy.
The tensor analyzing power T20 in deuteron break-up reactions within the Bethe-Salpeter formalism
The deuteron tensor analyzing power T20 in the deuteron break-up reaction Dp → pX is calculated within a relativistic approach based on the Bethe-Salpeter equation with a realistic meson-exchange potential. Our results on T20 and the cross section are compared with experimental data and non-relativistic calculations and with the outcome of a relativization procedure of the deuteron wave function. (orig.)
Shimizu Y.
2010-04-01
Full Text Available Measurements of a complete set of deuteron analyzing powers (iT11, T20, T21, T22 for elastic deuteron–proton scattering at 250 MeV/nucleon have been performed with polarized deuteron beams at RIKEN RI Beam Factory. The obtained data are compared with the Faddeev calculations based on the modern nucleon–nucleon forces together with the Tucson-Melbourne’99, and UrbanaIX three nucleon forces.
Prokofyeva A.S.
2014-12-01
Full Text Available The aim: to analyze the real power frequency magnetic field (50 Hz values near power lines. The material. Long-term measurements of the power frequency magnetic field (50 Hz near power lines of 110 kV, 220 kVand 500 kVin the Moscow region. Methods. Measurements were made by tracks which were perpendicular to the wires. Length of tracks was up to 40 m. Sensor of measurer was located on 1.8 m under the ground. General quantity of measurement points were 1103. The results. Was obtained general characteristics of real values of strength of electric field and values of magnetic flux density depending to distance to the projection last wire near power lines. Conclusion. Analysis of the results has the values of the magnetic field of power lines correspond to the Russian rules in all cases. Using additional World Health Organization safety criteria for magnetic fields (the class of carcinogenic risks 2B requires the expansion of the health safety zone 2-3 times.
Munoz, Joseph A
2012-01-01
We develop a radiation pressure-balanced model for the interstellar medium of high-redshift galaxies that describes many facets of galaxy formation at z>~6, including star formation rates and distributions and gas accretion onto central black holes. We first show that the vertical gravitational force in the disk of such a model is dominated by the disk self-gravity but that both radiation pressure on dust grains and turbulent pressure from dense clumps and disk instabilities are negligible compared with the radiation pressure of starlight on gas. Constraining our model to reproduce the UV luminosity function of Lyman-break galaxies (LBGs), we limit the available parameter-space to wind mass-loading factors 1--4 times the canonical value for momentum-driven winds. We then focus our study by exploring the effects of different angular momentum transport mechanisms in the galactic disk and find that viscosity driven by gravitational torques, such as from linear spiral waves or non-linear orbit crossings, can buil...
Dalton, Brian H.; Power, Geoffrey A; Paturel, Justin R.; Rice, Charles L.
2015-01-01
The underlying factors related to the divergent findings of age-related fatigue for dynamic tasks are not well understood. The purpose here was to investigate age-related fatigability and recovery between a repeated constrained (isokinetic) and an unconstrained velocity (isotonic) task, in which participants performed fatiguing contractions at the velocity (isokinetic) or resistance (isotonic) corresponding with maximal power. To compare between tasks, isotonic torque–power relationships were...
Vector analyzing power iT11 in πd elastic scattering at 49 MeV
Measurements of the vector analyzing power iT11 in πd elastic scattering at 49 MeV have been performed using a dynamically polarized target and a magnetic spectrometer. Data at seven π+ laboratory scattering angles between 50 degree and 130 degree were taken together with a complementary measurement at 60 degree for π-d elastic scattering. In general, we find agreement with models that include the πN P11 amplitude and disagreement with models that exclude or suppress it
We present new measurements of the analyzing power AN in proton-proton elastic scattering in the Coulomb-Nuclear Interference region at √s 7.7 and 21.7 GeV obtained with the polarized atomic hydrogen jet target at RHIC. These measurements complement our earlier results at √s = 6.8 and 13.7 GeV confirming the presence of a hadronic helicity flip amplitude contribution in proton-proton elastic scattering at lower energies (√s 13 GeV) are consistent with no hadronic helicity flip contribution.
Calculation of vector analyzing power in the p+6,8He elastic scattering at intermediate energies
Ibraeva Elena
2014-03-01
Full Text Available A calculations of the analyzing power (Ay of the elastic proton scattering on 6He and 8He are presented in the framework of the Glauber multiple diffraction scattering at E = 71 and 1000 MeV/nucleon. The wave functions obtained in the three-body α-n-n-model for 6He and the density distribution function in the no-core shell model for 8He are used. Our calculations qualitatively reproduced the data of Ay for p6He and p8He scattering and compare with the calculations’ results in the other approaches.
Fleck, Derek; Hoffnagle, John; Tan, Sze; He, Yonggang
2016-04-01
Greenhouse gas accumulation has contributed to the changes in environments across the globe. Monitoring these fluctuations on global and local scales will allow scientists to better understand contributions that are made from nature and humans. This has led to the deployment of analytical instrumentation of all types to the most remote areas as well as the most densely populated areas. This however requires instruments to be precise, versatile, robust, and most importantly have power requirements that are as not limited by location, i.e. low enough power consumption to run off of batteries or even solar array. Here we present a full greenhouse gas analyzer that utilizes a new method of CRDS to measure carbon dioxide, methane and water vapor that consumes only 25W and still maintains long term stability to allow for averaging time of over 3 hours. Measurements have a 1-σ precision of 30 ppb for CO2 and 300 ppt of CH4 with 5 minutes of averaging; and with measurements of 3 hour averages reaching precisions down to 40ppt of methane. Additionally this new flavor of CRDS has allowed for an overall increase in measurement dynamic range from traditional CW-CRDS measuring methane up to 1000ppm and carbon dioxide up to several percent. We will present supplemental data acquired using this <11 kg analyzer, including soil respirations using closed static chambers and 10m tower measurements from Santa Clara, CA.
Due to the increase application of nuclear energy for producing electricity, special attention must be paid to their maintenance activities in general and preventive maintenance in particular. It has been shown that a well established preventive maintenance programme will enhance the reliability and availability of nuclear power plants. A model of preventive maintenance for Buhehr nuclear power plant which is due to be completed by 2001 is developed. The prescribed model is based on past experiences of VVER nuclear power plants around the world. The utilized data is provided by International Atomic Energy Agency (IAEA) in Vienna, Austria. The data and past experiences reveal such important information as availability, energy loss, types of failures, duration of failure, etc. A strategy for designing a database is established. These data are then analyzed by statistical methods such as Pareto analysis, t-test, K-S test, analysis of variance, etc. The results of our analysis reveal important information in regard to establishment of a well-defined preventive maintenance programme in Buhshehr nuclear power plant. The results show that certain equipment such turbo-generator and control-rods play an important role in the maintenance of a VVER nuclear power plant. Other findings are discussed in great detail
Mikula, V. A.; Ryzhkov, A. F.; Val'tsev, N. V.
2015-11-01
Combined-cycle power plants operating on solid fuel have presently been implemented only in demonstration projects. One of possible ways for improving such plants consists in making a shift to hybrid process circuits of integrated gasification combined-cycle plants with external firing of solid fuel. A high-temperature air heater serving to heat compressed air is a key element of the hybrid process circuit. The article describes application of a high-temperature recuperative metal air heater in the process circuit of an integrated gasification combined-cycle power plant (IGCC). The available experience with high-temperature air heating is considered, and possible air heater layout arrangements are analyzed along with domestically produced heat-resistant grades of steel suitable for manufacturing such air heater. An alternative (with respect to the traditional one) design is proposed, according to which solid fuel is fired in a noncooled furnace extension, followed by mixing the combustion products with recirculation gases, after which the mixture is fed to a convective air heater. The use of this design makes it possible to achieve considerably smaller capital outlays and operating costs. The data obtained from thermal and aerodynamic calculations of the high-temperature air heater with a thermal capacity of 258 MW for heating air to a temperature of up to 800°C for being used in the hybrid process circuit of a combined-cycle power plant are presented.
De Bernardis, P; Bock, J J; Bond, J R; Borrill, J; Boscaleri, A; Coble, K; Contaldi, C R; Crill, B P; De Troia, G; Farese, P; Ganga, K; Giacometti, M; Hivon, E; Hristov, V V; Iacoangeli, A; Jaffe, A H; Jones, W C; Lange, A E; Martinis, L; Masi, S; Mason, P; Mauskopf, P D; Melchiorri, A; Montroy, T; Netterfield, C B; Pascale, E; Piacentini, F; Pogosyan, D; Polenta, G; Pongetti, F; Prunet, S; Romeo, G; Ruhl, J E; Scaramuzzi, F
2002-01-01
Three peaks and two dips have been detected in the power spectrum of the cosmic microwave background from the BOOMERANG experiment, at $\\ell \\sim 210, 540, 840$ and $\\ell \\sim 420, 750$, respectively. Using model-independent analyses, we find that all five features are statistically significant and we measure their location and amplitude. These are consistent with the adiabatic inflationary model. We also calculate the mean and variance of the peak and dip locations and amplitudes in a large 7-dimensional parameter space of such models, which gives good agreement with the model-independent estimates, and forecast where the next few peaks and dips should be found if the basic paradigm is correct. We test the robustness of our results by comparing Bayesian marginalization techniques on this space with likelihood maximization techniques applied to a second 7-dimensional cosmological parameter space, using an independent computational pipeline, and find excellent agreement: $\\Omega_{\\rm tot} = 1.02^{+0.06}_{-0.05...
de Bernardis, P.; Ade, P.A.R.; Bock, J.J.; Bond, J.R.; Borrill,J.; Boscaleri, A.; Coble, K.; Contaldi, C.R.; Crill, B.P.; De Troia, G.; Farese, P.; Ganga, K.; Giacometti, M.; Hivon, E.; Hristov, V.V.; Iacoangeli, A.; Jaffe, A.H.; Jones, W.C.; Lange, A.E.; Martinis, L.; Masi, S.; Mason, P.; Mauskopf, P.D.; Melchiorri, A.; Montroy, T.; Netterfield, C.B.; Pascale, E.; Piacentini, F.; Pogosyan, D.; Polenta,G.; Pongetti, F.; Prunet, S.; Romeo, G.; Ruhl, J.E.; Scaramuzzi, F.
2001-05-17
Three peaks and two dips have been detected in the power spectrum of the cosmic microwave background from the BOOMERANG experiment, at {ell} {approx} 210, 540, 840 and {ell} {approx} 420, 750, respectively. Using model-independent analyses, we find that all five features are statistically significant and we measure their location and amplitude. These are consistent with the adiabatic inflationary model. We also calculate the mean and variance of the peak and dip locations and amplitudes in a large 7-dimensional parameter space of such models, which gives good agreement with the model-independent estimates, and forecast where the next few peaks and dips should be found if the basic paradigm is correct. We test the robustness of our results by comparing Bayesian marginalization techniques on this space with likelihood maximization techniques applied to a second 7-dimensional cosmological parameter space, using an independent computational pipeline, and find excellent agreement: {Omega}{sub tot} = 1.02{sub -0.05}{sup +0.06} vs. 1.04 {+-} 0.05, {Omega}{sub b}h{sup 2} = 0.022{sub -0.003}{sup +0.004} vs. 0.019{sub -0.004}{sup +0.005}, and n{sub s} = 0.96{sub -0.09}{sup +0.10} vs. 0.90 {+-} 0.08. The deviation in primordial spectral index n{sub s} is a consequence of the strong correlation with the optical depth.
Bazilevsky A.; Alekseev, I.; Aschenauer, E.; Atoyan, G.; Bravar, A.; Bunce, G.; Boyle, K.; Gill, R.; Huang, H.; Lee, S.; Makdisi, Y.; Morozov, B.; Nakagawa, I.; Okada, H.; Svirida, D.; Zelenski, A.
2010-09-27
We present new measurements of the analyzing power A{sub N} in proton-proton elastic scattering in the Coulomb-Nuclear Interference region at {radical}s = 7.7 and 21.7 GeV obtained with the polarized atomic hydrogen jet target at RHIC. These measurements complement our earlier results at {radical}s = 6.8 and 13.7 GeV confirming the presence of a hadronic helicity flip amplitude contribution in proton-proton elastic scattering at lower energies ({radical}s <8 GeV) while higher energy data ({radical}s >13 GeV) are consistent with no hadronic helicity flip contribution.
马晓三; 于治福; 商德勇
2011-01-01
Using the functional relationships among the initiative input angle, input angular velocity and output angular velocity of a single-cross universal joint, we derive the functional relationship of the transmission shaft composed of two cross universal tandem joints under the condition that three shafts are located in different planes. With these functional relationships, we verify the constant-velocity condition of the cress universal transmission shaft. Then we use the step-by-step search algorithm to determine the optimal phase angle that leads to the minimum fluetuation of the output angular velocity under the varying-velocity condition and to search the maximum and minimum values of the output angular velocity and their corresponding input angles. Finally, we use an ADAMS simulation example to verify that the output angular velocity function and the step-by-step search algorithm are correct.%以由两个十字轴万向节串联组成的传动轴为研究对象，以单十字轴万向节输出角速度计算公式为基础，通过研究两级输入转角之间的关系，推导出了三轴不同面时输出角速度与输入转角、输入角速度之间的函数关系。通过该函数关系，对十字轴万向传动轴等速条件进行了验证，并运用逐步搜索的方法编程确定了不等速条件下使输出角速度波动最小的相位角，在相位角确定时逐步搜索出输出角速度的最大值、最小值及其对应的输入转角。ADAMS仿真实例对输出角速度函数和逐步搜索算法的正确性进行了验证。
The COMMIX-PPC computer pregrain is an extended and improved version of earlier COMMIX codes and is specifically designed for evaluating the thermal performance of power plant condensers. The COMMIX codes are general-purpose computer programs for the analysis of fluid flow and heat transfer in complex Industrial systems. In COMMIX-PPC, two major features have been added to previously published COMMIX codes. One feature is the incorporation of one-dimensional equations of conservation of mass, momentum, and energy on the tube stile and the proper accounting for the thermal interaction between shell and tube side through the porous-medium approach. The other added feature is the extension of the three-dimensional conservation equations for shell-side flow to treat the flow of a multicomponent medium. COMMIX-PPC is designed to perform steady-state and transient. Three-dimensional analysis of fluid flow with heat transfer tn a power plant condenser. However, the code is designed in a generalized fashion so that, with some modification, it can be used to analyze processes in any heat exchanger or other single-phase engineering applications. Volume I (Equations and Numerics) of this report describes in detail the basic equations, formulation, solution procedures, and models for a phenomena. Volume II (User's Guide and Manual) contains the input instruction, flow charts, sample problems, and descriptions of available options and boundary conditions
Chien, T.H.; Domanus, H.M.; Sha, W.T.
1993-02-01
The COMMIX-PPC computer program is an extended and improved version of earlier COMMIX codes and is specifically designed for evaluating the thermal performance of power plant condensers. The COMMIX codes are general-purpose computer programs for the analysis of fluid flow and heat transfer in complex industrial systems. In COMMIX-PPC, two major features have been added to previously published COMMIX codes. One feature is the incorporation of one-dimensional conservation of mass. momentum, and energy equations on the tube side, and the proper accounting for the thermal interaction between shell and tube side through the porous medium approach. The other added feature is the extension of the three-dimensional conservation equations for shell-side flow to treat the flow of a multicomponent medium. COMMIX-PPC is designed to perform steady-state and transient three-dimensional analysis of fluid flow with heat transfer in a power plant condenser. However, the code is designed in a generalized fashion so that, with some modification. it can be used to analyze processes in any heat exchanger or other single-phase engineering applications.
Franz, Robert; Kolbeck, Jonathan; Anders, André
2016-01-01
The ion energies and fluxes in the high power impulse magnetron sputtering plasma from a Nb target were analysed angularly resolved along the tangential direction of the racetrack. A reactive oxygen-containing atmosphere was used as such discharge conditions are typically employed for the synthesis of thin films. Asymmetries in the flux distribution of the recorded ions as well as their energies and charge states were noticed when varying the angle between mass-energy analyser and target surface. More positively charged ions with higher count rates in the medium energy range of their distributions were detected in $+\\mathbf{E}\\times \\mathbf{B}$ than in $-\\mathbf{E}\\times \\mathbf{B}$ direction, thus confirming the notion that ionisation zones are associated with moving potential humps. The motion of the recorded negatively charged high-energy oxygen ions was unaffected. NbO$_x$ thin films at different angles and positions were synthesised and analysed as to their structure and properties in order to correlate ...
Kudoh, H; Kudoh, Hideaki; Taruya, Atsushi
2005-01-01
We discuss the sensitivity to anisotropies of stochastic gravitational-wave backgrounds (GWBs) observed via space-based interferometer. In addition to the un-resolved Galactic binaries as the most promising GWB source of the planned Laser Interferometer Space Antenna (LISA), the extra-galactic sources for GWBs might be detected in the future space missions. The anisotropies of the GWBs thus play a crucial role to discriminate various components of the GWBs. We study general features of antenna pattern sensitivity to the anisotropies of GWBs beyond the low-frequency approximation. We show that the sensitivity of space-based interferometer to GWBs is severely restricted by the data combinations and the symmetries of the detector configuration. The spherical harmonic analysis of the antenna pattern functions reveals that the angular power of the detector response increases with frequency and the detectable multipole moments with effective sensitivity h_{eff}\\sim 10^{-20} Hz^{-1/2} may reach $\\ell \\sim $ 8 - 10 a...
We discuss the sensitivity to anisotropies of stochastic gravitational-wave backgrounds (GWBs) observed via space-based interferometer. In addition to the unresolved galactic binaries as the most promising GWB source of the planned Laser Interferometer Space Antenna (LISA), the extragalactic sources for GWBs might be detected in the future space missions. The anisotropies of the GWBs thus play a crucial role to discriminate various components of the GWBs. We study general features of antenna pattern sensitivity to the anisotropies of GWBs beyond the low-frequency approximation. We show that the sensitivity of space-based interferometer to GWBs is severely restricted by the data combinations and the symmetries of the detector configuration. The spherical harmonic analysis of the antenna pattern functions reveals that the angular power of the detector response increases with frequency and the detectable multipole moments with effective sensitivity heff∼10-20 Hz-1/2 may reach l∼8-10 at f∼f*=10 mHz in the case of the single LISA detector. However, the cross correlation of optimal interferometric variables is blind to the monopole (l=0) intensity anisotropy, and also to the dipole (l=1) in some case, irrespective of the frequency band. Besides, all the self-correlated signals are shown to be blind to the odd multipole moments (l=odd), independently of the frequency band
The analyzing powers of π+ and π- were measured using an incident 22-GeV/c transversely polarized proton beam at the Brookhaven Alternating Gradient Synchrotron. A magnetic spectrometer measured π± inclusive asymmetries on a hydrogen and a carbon target. An elastic polarimeter with a CH2 target measured pp elastic-scattering asymmetries to determine the beam polarization using published data for the pp elastic analyzing power. Using the beam polarization determined from the elastic polarimeter and asymmetries from the inclusive spectrometer, analyzing powers AN for π± were determined in the xF and pT ranges (0.45-0.8) and (0.3-1.2 GeV/c), respectively. The analyzing power results are similar in both sign and character to other measurements at 200 and 11.7 GeV/c, confirming the expectation that high-energy pion inclusive analyzing powers remain large and relatively energy independent. This suggests that pion inclusive polarimetry may be a suitable method for measuring future beam polarizations at BNL RHIC or DESY HERA. Analyzing powers of π+ and π- produced on hydrogen and carbon targets are the same. Various models to explain inclusive analyzing powers are also discussed
The Second CSNI Specialist Meeting on Simulators and Plant Analyzers: Current Issues in Nuclear Power Plant Simulation was held in Espoo, Finland, from September 29 through October 2, 1997. It was organised by CSNI Principal Working Group on Coolant System Behaviour (PWG2), Task Group on Thermal Hydraulic Applications (TG-THA), in co-operation with Technical Research Centre of Finland. The meeting in Espoo attracted some 90 participants from 17 countries. A total of 49 invited papers were presented in the meeting in addition to 7 simulator system demonstrations. Ample time was reserved for the presentations and informal discussions during the four meeting days. The previous meeting held in Lappeenranta, Finland, in 1992 collected some 85 participants from 12 countries, presenting a total of 40 papers. The meeting was structured into 6 sessions covering the important aspects of development and use of simulators and plant analyzers: Session I: New objectives, Requirements and Concepts. This session covered the progress experienced since the 1. simulator meeting and tried to address the changing role of simulators based on the changes in users' needs and developing possibilities. Session II: Trends in Simulation Technology. This session was reserved for studying the current trends in the simulation technology: software environments, visualisation, simulator configuration tools, programming languages and computer systems. Session III: Training and human factor studies using simulators. This session was created for studying the status of different uses of simulators such as educational simulators, human factor studies and integrated safety assessment in addition to traditional training. Regarding to the severe accidents, a question was raised whether the simulator use should be for training or education. Session IV: Modelling techniques. The session on modelling techniques was included to cover recent developments in the modelling techniques applicable to training
The study of ergonomics has evolved around the world as one of the keys to understand human behavior in interaction with complex systems as nuclear power plant and to achieve the best match between the system and its users in the context of task to be performed. Increasing research efforts have yielded a considerable body of knowledge concerning the design of workstations, workplace, control rooms, human-system interfaces, user-interface interaction and organizational design to prevent worker discomfort, illness and also to improve productivity, product quality, ease of use and safety. The work ergonomics analysis consists of gathering a series of observation in order to better understand the work done and to propose changes and improvements in the working conditions. The work ergonomics analysis implies both the correction of existing situations (safety, reliability and production problems) and the development of new work system. Operator activity analysis provides a useful tool for the ergonomics approach, based on work ergonomics analysis. The operators will be systematically observed in their real work environment (control room) or in simulators. The focus is on description of the distributed regulated mechanisms (in the sense that operators work in crew), both in nominal and degraded situations, observing how operators regulate collectively their work during an increase in workload or when confronted with situations where incidents or accidents occur. Audio, video recorders and field notes can be used to collect empirical data, conversations and interactions that occur naturally within the work environment. Our research develops an applied ergonomics methodology, based on field studies, that permits to identify and analyze situations, factors that may affect the operational performance of nuclear power plants. Our contribution is related to the following technical topic: How best to learn from and share operational safety experience and manage changes during
Analyzing WMAP Observation by Quantum Gravity
Hamada, Ken-ji; Sugiyama, Naoshi; Yukawa, Tetsuyuki
2007-01-01
The angular power spectra of cosmic microwave background are analyzed under the light of the evolutional scenario of the universe based on the renormalizable quantum theory of gravity in four dimensions. The equation of evolution is solved numerically fixing the power law spectrum predicted by the conformal gravity for the initial condition. The equation requires to introduce a dynamical energy scale about 10^{17}GeV, where the inflationary space-time evolution makes a transition to the big-bang of the conventional Friedmann universe. The quality of fit to the three-year data of WMAP implies the possibility to understand the observation by quantum gravity.
Tensorial analyzing power T20 at 1800C.M. in d vector p elastic scattering between 0.3 and 2.3 GeV
The results of the measurement of the analysing power T20 at 1800 CM in d vector p elastic scattering for 16 energies between 300 and 2300 MeV are presented. The values which have been obtained are badly reproduced by the calculations based on neutron transfer (ONT) and Δ excitation in the intermediate state (TME) mechanisms, principal beyond 1 GeV. The excitation of possible tribaryon resonances, which are introduced in an elementary way, is added to these two mechanisms. The results of these calculations show that one could thus obtain a satisfying agreement with the experimental values. A measurement of angular distribution of the analysing powers Asub(y) and Asub(yy) between 70 and 1800 CM at 1200 MeV is also presented
We have carried out the experiment BNL-AGS E950 to measure the analyzing power for proton-carbon elastic scattering in the Coulomb-Nuclear Interference (CNI) region with a 22 GeV/c polarized proton beam. Recoil carbons from 300 keV to a few MeV in the CNI region, were detected inside the AGS ring to identify proton-carbon elastic scattering. The preliminary results of the analyzing power measurement are presented
The free neutron-proton analyzing power and the spin transfer parameters (K/sub NN/, K/sub SS/, K/sub SL/, and K/sub LL/) were measured at the Los Alamos Meson Physics Facility at 790 MeV between 1650 and 1800 center of mass. A 40% polarized neutron beam incident on a liquid hydrogen target was used. The recoil protons were momentum analyzed with a magnetic spectrometer to isolate elastic scatters. A large solid angle carbon polarimeter was used to measure the proton polarization. The measurements are the first at this energy and are in basic agreement with pre-existing phase shift solutions. The proton-carbon analyzing power was measured between 500 and 750 MeV. An empirical fit to the proton-carbon analyzing power between 100 and 750 MeV was done
Ransome, R.D.
1981-07-01
The free neutron-proton analyzing power and the spin transfer parameters (K/sub NN/, K/sub SS/, K/sub SL/, and K/sub LL/) were measured at the Los Alamos Meson Physics Facility at 790 MeV between 165/sup 0/ and 180/sup 0/ center of mass. A 40% polarized neutron beam incident on a liquid hydrogen target was used. The recoil protons were momentum analyzed with a magnetic spectrometer to isolate elastic scatters. A large solid angle carbon polarimeter was used to measure the proton polarization. The measurements are the first at this energy and are in basic agreement with pre-existing phase shift solutions. The proton-carbon analyzing power was measured between 500 and 750 MeV. An empirical fit to the proton-carbon analyzing power between 100 and 750 MeV was done.
Karpov, Valeri
2015-01-01
A comprehensive guide to AngularJS, Google's open-source client-side framework for app development. Most of the existing guides to AngularJS struggle to provide simple and understandable explanations for more advanced concepts. As a result, some developers who understand all the basic concepts of AngularJS struggle when it comes to building more complex real-world applications. Professional AngularJS provides a thorough understanding of AngularJS, covering everything from basic concepts, such as directives and data binding, to more advanced concepts like transclusion, build systems, and auto
Compact Microwave Fourier Spectrum Analyzer
Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitry
2009-01-01
A compact photonic microwave Fourier spectrum analyzer [a Fourier-transform microwave spectrometer, (FTMWS)] with no moving parts has been proposed for use in remote sensing of weak, natural microwave emissions from the surfaces and atmospheres of planets to enable remote analysis and determination of chemical composition and abundances of critical molecular constituents in space. The instrument is based on a Bessel beam (light modes with non-zero angular momenta) fiber-optic elements. It features low power consumption, low mass, and high resolution, without a need for any cryogenics, beyond what is achievable by the current state-of-the-art in space instruments. The instrument can also be used in a wide-band scatterometer mode in active radar systems.
Vector and tensor analyzing powers in the 208Pb(vector d,t)207Pb reaction at 200 and 360 MeV
Cross-sections, vector and tensor analyzing powers for the main levels in 207Pb have been measured via the 208Pb (d,t) 207Pb reaction at 200 and 360 MeV incident energies. Ay and Ayy spin observables allow a clear identification of the valence levels, especially at 200 MeV. The results are compared with finite range DWBA calculations using the Paris projectile-ejectile form factor including the S and D components. The analysis shows a large effect of the D component on the tensor analyzing powers at the most forward angles. At both energies, the spin part of the deuteron optical potential is very important to describe the analyzing powers and especially Ayy. The good description of all observables at 200 MeV allows this reaction to be used as a spectroscopic tool
Tojo, J; Alekseev, I; Bai, M; Bassalleck, B; Bunce, G; Deshpande, A; Doskow, J; Eilerts, S; Fields, D E; Goto, Y; Huang, H; Hughes, V; Imai, K; Ishihara, M; Kanavets, V; Kurita, K; Kwiatkowski, K; Lewis, B; Lozowski, W; Makdisi, Y; Meyer, H-O; Morozov, B V; Nakamura, M; Przewoski, B; Rinckel, T; Roser, T; Rusek, A; Saito, N; Smith, B; Svirida, D; Syphers, M; Taketani, A; Thomas, T L; Underwood, D; Wolfe, D; Yamamoto, K; Zhu, L
2002-07-29
The analyzing power for proton-carbon elastic scattering in the Coulomb-nuclear interference region of momentum transfer, 9.0x10(-3)<-t<4.1x10(-2) (GeV/c)(2), was measured with a 21.7 GeV/c polarized proton beam at the Alternating Gradient Synchrotron of Brookhaven National Laboratory. The ratio of hadronic spin-flip to nonflip amplitude, r(5), was obtained from the analyzing power to be Rer(5)=0.088+/-0.058 and Imr(5)=-0.161+/-0.226. PMID:12144435
The analyzing power for proton-carbon elastic scattering in the Coulomb-nuclear interference region of momentum transfer, 9.0x10-3-2 (GeV/c)2, was measured with a 21.7 GeV/c polarized proton beam at the Alternating Gradient Synchrotron of Brookhaven National Laboratory. The ratio of hadronic spin-flip to nonflip amplitude, r5, was obtained from the analyzing power to be Rer5=0.088±0.058 and Imr5=-0.161±0.226
We have measured the analyzing power in π+, π-, and KS0 production by a polarized proton beam at 13.3 and 18.5 GeV/c. The data cover the central and the beam fragmentation region, in the transverse-momentum range up to 2 GeV/c. The results indicate that sizable effects are present at high xF and also persist into the hard-scattering region for KS0 and π+. A zero value of the analyzing power was observed for π- production
Measurement of the tensor-analyzing power A sub y sub y in deuteron breakup at 4.5 GeV/c and 80 mr
Ladygin, V P; Afanasiev, S V; Arkhipov, V V; Isupov, A Yu; Ivanov, V I; Kashirin, V A; Khrenov, A N; Kolesnikov, V I; Kuznetsov, V A; Ladygina, N B; Litvinenko, A G; Reznikov, S G; Rukoyatkin, P A; Semenov, A Yu; Semenova, I A; Stoletov, G D; Zhmyrov, V N; Zolin, L S; Bondarev, V K; Filipov, G; Kartamyshev, A A; Yudin, N P
2002-01-01
The tensor analyzing-power A sub y sub y in inclusive breakup of 4.5 GeV/c deuterons on berylium has been measured at /sim 80 mr of the detected proton angle. The analyzing power remains positive up to the highest measured momentum of the proton, that is in definitive contradiction with the predictions of the existing models based on the standard deuteron wave functions. The results suggest that the deuteron structure at short distances may depend on more than one independent variable. (author)
A new high-energy beam polarimeter is proposed for the Nuclotron using Internal Target Station. This polarimeter based on the measurement of the asymmetry for the d-p elastic scattering will allow one to measure both vector and tensor components of the deuteron beam polarization simultaneously. For that purpose the measurement of analyzing powers for the d-p elastic scattering at energies Td = 0.88-2 GeV is proposed. The precise measurements of the deuteron analyzing powers over energy range Td 300-2000 MeV can give an irreplaceable clue on the study of spin-dependence of three-nucleon forces
Measurement of the tensor-analyzing power Ayy in deuteron breakup at 4.5 GeV/c and 80 mr
The tensor analyzing-power Ayy in inclusive breakup of 4.5 GeV/c deuterons on berylium has been measured at /sim 80 mr of the detected proton angle. The analyzing power remains positive up to the highest measured momentum of the proton, that is in definitive contradiction with the predictions of the existing models based on the standard deuteron wave functions. The results suggest that the deuteron structure at short distances may depend on more than one independent variable. (author)
Quark Orbital Angular Momentum
Burkardt Matthias
2015-01-01
Definitions of orbital angular momentum based on Wigner distributions are used as a framework to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar. We find that the difference between these two definitions can be interpreted as the change in the quark orbital angular momentum as it leaves the target in a DIS experiment. The mechanism responsible for that change is similar to the mechanism that causes transverse single-spin asy...
Partonic orbital angular momentum
Arash, Firooz; Taghavi-Shahri, Fatemeh; Shahveh, Abolfazl
2013-04-01
Ji's decomposition of nucleon spin is used and the orbital angular momentum of quarks and gluon are calculated. We have utilized the so called valon model description of the nucleon in the next to leading order. It is found that the average orbital angular momentum of quarks is positive, but small, whereas that of gluon is negative and large. Individual quark flavor contributions are also calculated. Some regularities on the total angular momentum of the quarks and gluon are observed.
Xie, Guodong; Ren, Yongxiong; Huang, Hao; Yan, Yan; Ahmed, Nisar; Zhao, Zhe; Lavery, Martin P J; Ashrafi, Nima; Ashrafi, Solyman; Tur, Moshe; Molisch, Andreas F; Willner, Alan E
2014-01-01
We study the design parameters for an orbital angular momentum (OAM) multiplexed free-space data link. Power loss, channel crosstalk and power penalty of the link are analyzed in the case of misalignment between the transmitter and receiver (lateral displacement, receiver angular error, or transmitter pointing error). The relationship among the system power loss and link distance, transmitted beam size and receiver aperture size are discussed based on the beam divergence due to free space propagation. We also describe the trade-offs for different receiver aperture sizes and mode spacing of the transmitted OAM beams under given lateral displacements or receiver angular errors. Through simulations and some experiments, we show that (1) a system with a larger transmitted beam size and a larger receiver aperture is more tolerant to the lateral displacement but less tolerant to the receiver angular error; (2) a system with a larger mode spacing, which uses larger OAM charges, suffers more system power loss but les...
Feijoo, Santiago Rodriguez; Caro, Alejandro Rodriguez; Correa, Carlos Gonzalez
2003-01-01
In the present paper an index to measure the changes in the Absolute Purchasing Power Parity. in the short term of a group of territories that conform an unique market, using the information of the Harmonized Index of Consumer Prices and the Exchange Rates. This measurement is utilized to study the change in relative prices of the countries of the European Union for the period 1991-2002, and the fulfillment of the theory of the Relative Purchasing Power Parity, taking as a reference the Absol...
Jeong, Won Sang; Kim, Shin Whan; Sung, Kang Sik; Seo, Jong Tae; Lee, Sang Keun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)
1996-07-01
The Loss of a Main Feedwater Pump test at 100% Power for YGN 4 was simulated in order to verify and validate the KSNPA. The comparison of the test data with the KSNPA prediction results showed reasonable agreement in the trends of the major plant parameters. All plant control systems including NSSS and T/G control systems are properly actuated and stabilized the plant conditions to a new steady state conditions in the KSNPA. From the comparison results, the KSNPA showed its capability to simulate the LOMFP event for the KOrean Standard Nuclear Power Plant.
Rotations and angular momentum
This paper is devoted to the analysis of rotational invariance and the properties of angular momentum in quantum mechanics. In particular, the problem of addition of angular momenta is treated in detail, and tables of Clebsch-Gordan coefficients are included
The analyzing power for the elastic and inelastic neutron scattering to the first excited state on 12C was measured at 21 energies from 6.8 to 17.3 MeV. The data from 8.9 to 14.9 MeV were together with very precise cross section data from the literature studied in the framework of the spherical optical model and the coupled channel formalism. The coupled channel analysis of the elastic and inelastic scattering on 12C in the framework of the rotator model yielded a good agreement between measured and calculated angular distributions. The determined quadrupole deformation parameter β2 = -0.67 agrees well with values from the literature. The existence of different qudrupole deformations for the central and spin-orbit components of the optical potential was studied. Large differences for the quadrupole deformations β2sup(c) and β2sup(so) were found at 8.9, 11.9, and 12.9 MeV. Especially at 8.9 MeV by this a great improvement of the fit to the data was reached. (orig./HSI)
ZKDR Distance, Angular Size and Phantom Cosmology
R.C. Santos; Lima, J. A. S.
2006-01-01
The influence of mass inhomogeneities on the angular size-redshift test is investigated for a large class of flat cosmological models driven by dark energy plus a cold dark matter component. The results are presented in two steps. First, the mass inhomogeneities are modeled by a generalized Zeldovich-Kantowski-Dyer-Roeder (ZKDR) distance which is characterized by a smoothness parameter $\\alpha(z)$ and a power index $\\gamma$, and, second, we provide a statistical analysis to angular size data ...
Shell effects and fission fragments angular anisotropy
The impact of the shell corrections attenuation effect with growth of the fissionable nuclei temperature on the angular anisotropy of the fission fragments is considered. The experimental data on the anisotropy of the fission fragments angular distributions of the compound nucleus, formed in the 4He + 238U reactions, are analyzed within the frames of the transition states model in the fission barriers saddle point and statistic theory of nuclear reactions. The obvious kind of the shell corrections attenuation function is obtained
Orbital angular momentum of partially coherent beams
Serna Galán, Julio; Movilla Serrano, Jesús María
2001-01-01
The definition of the orbital angular momentum established for coherent beams is extended to partially coherent beams, expressed in terms of two elements of the beam matrix. This extension is justified by use of the Mercer expansion of partially coherent fields. General Gauss-Schell-model fields are considered, and the relation between the twist; parameter and the orbital angular momentum is analyzed. © 2001 Optical Society of America.
The (p,pα) reaction on 12C was investigated experimentally using polarized incident protons of 100 MeV. The scattered proton and α particle, from the knockout reaction, were detected in coincidence. Coincident data, which were obtained at ten quasifree angle pairs for proton angles ranging from 25 deg. to 110 deg., were analyzed in terms of the distorted-wave impulse approximation (DWIA). Calculated energy-sharing cross section and analyzing power distributions reproduce the data reasonably well, indicating that a quasifree knockout mechanism dominates the reaction. Since measurements of analyzing powers were made, spin-orbit distortions were included in the DWIA calculations. The effects of this were found to be very small near zero recoil momentum and did not destroy the validity of the factorization approximation where the two-body p-α cross section enters as a multiplicative factor in the three-body (p,pα) cross section expression. Spectroscopic factors derived from the data are consistent with theoretical predictions. Analyzing power data also follow the trend of free p-4He scattering data, and comparisons with DWIA predictions are in reasonable agreement. Because the two-body interaction response between the projectile and the α cluster was found to resemble the scattering of protons from a free α particle to a remarkable degree, the present results would strongly imply the existence of preformed α clusters in 12C.
胡云; 王大辉; 赵学庆
2016-01-01
In high power excimer laser system, angular multiplexing technique is employed to achieve both high energy and narrow pulse output. In this article, angular multiplexing technique was introduced, and a multiplexing encoding method was presented. This method encoded seed beam in two steps by sequential amplitude splitting. The optical elements were arranged in rectangle arrays and piled by layers. A specific optical design was made for XeCl high power excimer laser system in this laboratory. This method of angular multiplexing encoding has advantages of compacted space, small encoding error, good compatibility with alignment and measurement, and is also easy to fabricate and assemble. This design is adopted in the system and performs well.%在高功率准分子激光系统中，一般采用光学角多路技术来获得高能量窄脉冲输出。文中介绍了角多路技术原理，提出了一种采用矩形阵列和空间层叠光路结构的连续分振幅两次编码方式，并针对该实验室的XeCl高功率准分子激光系统进行了具体的编码光路设计，给出了设计实例。该方法具有编码结构紧凑，编码精度高，与光路准直、激光参数测量系统等兼容性好，便于加工制作和安装调节等优点，目前已在系统中应用，效果良好。
Liebe, Wolfgang
1944-01-01
In many studies, especially of nonstationary flight motion, it is necessary to determine the angular velocities at which the airplane rotates about its various axes. The three-component recorder is designed to serve this purpose. If the angular velocity for one flight attitude is known, other important quantities can be derived from its time rate of change, such as the angular acceleration by differentiations, or - by integration - the angles of position of the airplane - that is, the angles formed by the airplane axes with the axis direction presented at the instant of the beginning of the motion that is to be investigated.
Quark Orbital Angular Momentum
Burkardt Matthias
2015-01-01
Full Text Available Definitions of orbital angular momentum based on Wigner distributions are used as a framework to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar. We find that the difference between these two definitions can be interpreted as the change in the quark orbital angular momentum as it leaves the target in a DIS experiment. The mechanism responsible for that change is similar to the mechanism that causes transverse single-spin asymmetries in semi-inclusive deep-inelastic scattering.
Azhgirey, L S; Zhmyrov, N V; Zolin, L S; Ivanov, V I; Isupov, A Yu; Ladygin, V P; Litvinenko, A G; Peresedov, V F; Khrenov, A N; Yudin, N P
2004-01-01
New data on the tensor analyzing power $A_{yy}$ of the $^9$Be$(d,p)X$ reaction at an initial deuteron momentum of 5 GeV/$c$ and a proton detection angle of 178 mrad have been obtained at the JINR Synchrophasotron. The data obtained are analyzed within the framework of an approach based on the light-front dynamics using Karmanov's relativistic deuteron wave function. In contrast to the calculations with standard non-relativistic deuteron wave functions, we have managed to explain the new data within the framework of our approach without invoking degrees of freedom additional to nucleon ones.
Cross sections and analyzing powers of 15N(p,n)15O at 200 MeV and 494 MeV
Differential cross sections and analyzing powers have been measured for the 15N(p,n)15 O(g.s.) reaction at bombarding energies of 200 MeV and 494 MeV. The 494 MeV data were obtained at the LAMPF Neutron Time-Of-Flight Facility on an 82 m flight path with a resolution of about 2.7 MeV. The 200 MeV data were obtained at IUCF on a 76m flight path with a resolution of about 1.1 MeV. At both energies, the measured analyzing power is small, the magnitude is less than .2 for momentum transfers of less than 1 fm-1. In contrast, both Relativistic and standard DWIA calculations predict a maximum of A=-.7 near q=0.7 fm-1. 53 refs., 44 figs
For many years the Institute of Physics has published books on hot topics based on a collection of reprints from different journals, including some remarks by the editors of each volume. The book on Optical Angular Momentum, edited by L Allen, S M Barnett and M J Padgett, is a recent addition to the series. It reproduces forty four papers originally published in different journals and in a few cases it provides direct access to works not easily accessible to a web navigator. The collection covers nearly a hundred years of progress in physics, starting from an historic 1909 paper by Poynting, and ending with a 2002 paper by Padgett, Barnett and coworkers on the measurement of the orbital angular momentum of a single photon. The field of optical angular momentum has expanded greatly, creating an interdisciplinary attraction for researchers operating in quantum optics, atomic physics, solid state physics, biophysics and quantum information theory. The development of laser optics, especially the control of single mode sources, has made possible the specific design of optical radiation modes with a high degree of control on the light angular momentum. The editors of this book are important figures in the field of angular momentum, having contributed to key progress in the area. L Allen published an historical paper in 1999, he and M J Padgett (together with M Babiker) produced few years ago a long review article which is today still the most complete basic introduction to the angular momentum of light, while S M Barnett has contributed several high quality papers to the progress of this area of physics. The editors' choice provides an excellent overview to all readers, with papers classified into eight different topics, covering the basic principles of the light and spin and orbital angular momentum, the laboratory tools for creating laser beams carrying orbital angular momentum, the optical forces and torques created by laser beams carrying angular momentum on
Van Essen, H.
2004-01-01
This paper addresses the problem of the separation of rotational and internal motion. It introduces the concept of average angular velocity as the moment of inertia weighted average of particle angular velocities. It extends and elucidates the concept of Jellinek and Li (1989) of separation of the energy of overall rotation in an arbitrary (non-linear) $N$-particle system. It generalizes the so called Koenig's theorem on the two parts of the kinetic energy (center of mass plus internal) to th...
Angular velocity discrimination
Kaiser, Mary K.
1990-01-01
Three experiments designed to investigate the ability of naive observers to discriminate rotational velocities of two simultaneously viewed objects are described. Rotations are constrained to occur about the x and y axes, resulting in linear two-dimensional image trajectories. The results indicate that observers can discriminate angular velocities with a competence near that for linear velocities. However, perceived angular rate is influenced by structural aspects of the stimuli.
Orbital angular momentum effects
This paper reports that in the context of the parton model description of baryon structure orbital angular momentum effects have long been considered negligible. However, recent results obtained within the framework of QCD and presented in this talk indicate that a substantial fraction of the baryon spin may be carried as orbital angular momentum of its constituents. These results are of particular relevance in the light of new data on the spin structure of the proton recently published by the EMC collaboration
The Role of X-Ray Diffraction for Analyzing Zr-Sn-Nb-Fe Alloys as Power Reactor Fuel Cladding
Synthesis of Zr- 1%Nb- 1%Sn- 1%Fe alloy is undertaken in order to develop fuel cladding alloy at high burn-up. Powder specimens of Zr-Sn-Nb-Fe alloy were prepared and then formed into pellets with a dimension of 10 mm in height x 10 mm in diameter using a pressure of 1.2 ton/cm2. The 5 gram green pellets were then melted in an arc furnace crucible under argon atmosphere. The pressure in the furnace was set at 2 psi and the current was 50 A. Afterwards, the ingots were heated at a temperature of 1100 oC for 2 hours and subsequently quenched in water. The ingots then underwent annealing at temperatures of 400 oC, 500 oC, 600 oC, 700 oC, and 750 oC for 2 hours. The specimens were analyzed using X-ray diffraction in order to construct diffractograms. Results of the diffraction patterns were fitted with data from JCPDF (Joint Committee Powder Diffraction File) to determine the type of crystals in the elements or substances. The greater the crystallite dimension, the smaller the dislocation density. Agreeable results for hardening or strengthening were obtained at annealing temperatures of 500 oC and 700, whereas for softening or residual stress at 600 oC and 750 oC. The nucleation of the secondary phase precipitate (SPP) was favourable at annealing temperatures of 400 oC, 500 oC, and 700 oC. For Zr- 1%Nb- 1%Sn- 1%Fe alloy with annealing temperatures between 400 oC to 800 oC, precipitates of Fe2Nb, ZrSn2,FeSn, SnZr, NbSn2, Zr0.68Nb0.25Fe0.08, Fe2Nb0.4Zr0.6, Fe37Nb9Zr54, and ω-Zr were observed. Satisfactory precipitate stabilization was achieved at annealing temperature of 800 oC, growth of precipitates at temperature between 500 oC to 600 oC, and minimization of precipitate size at 700 oC. (author)
The Role of X-Ray Diffraction for Analyzing Zr-Sn-Nb-Fe Alloys as Power Reactor Fuel Cladding
Sugondo
2010-08-01
Full Text Available Synthesis of Zr-1%Nb-1%Sn-1%Fe alloy is undertaken in order to develop fuel cladding alloy at high burn-up. Powder specimens of Zr-Sn-Nb-Fe alloy were prepared and then formed into pellets with a dimension of 10 mm in height 10 mm in diameter using a pressure of 1.2 ton/cm2. The 5 gram green pellets were then melted in an arc furnace crucible under argon atmosphere. The pressure in the furnace was set at 2 psi and the current was 50 A. Afterwards, the ingots were heated at a temperature of 1100°C for 2 hours and subsequently quenched in water. The ingots then underwent annealing at temperatures of 400°C, 500°C, 600°C, 700°C, and 750°C for 2 hours. The specimens were analyzed using X-ray diffraction in order to construct diffractograms. Results of the diffraction patterns were fitted with data from JCPDF (Joint Committee Powder Diffraction File to determine the type of crystals in the elements or substances. The greater the crystallite dimension, the smaller the dislocation density. Agreeable results for hardening or strengthening were obtained at annealing temperatures of 500°C and 700, whereas for softening or residual stress at 600°C and 750°C. The nucleation of the secondary phase precipitate (SPP was favourable at annealing temperatures of 400°C, 500°C, and 700°C. For Zr-1%Nb-1%Sn-1%Fe alloy with annealing temperatures between 400°C to 800°C, precipitates of Fe2Nb, ZrSn2,FeSn, SnZr, NbSn2, Zr0.68Nb0.25Fe0.08, Fe2Nb0.4Zr0.6, Fe37Nb9Zr54, and ω-Zr were observed. Satisfactory precipitate stabilization was achieved at annealing temperature of 800°C, growth of precipitates at temperature between 500°C to 600°C, and minimization of precipitate size at 700°C.
ERSOY, H. Volkan; BARIŞ, Serdar
2002-01-01
In this paper, the flow of a viscous fluid due to the non-coaxial rotations of a disk and the fluid at infinity with a slight angular velocity difference is studied. The effect of angular velocity difference on the velocity field is analyzed in detail. A perturbation series which is expressed in powers of the rotation parameter with nearly the same angular velocity and the shooting method using the fourth-order Runge-Kutta procedure are employed to solve the problem. It is proved that the r...
Characterization of the Bell-Shaped Vibratory Angular Rate Gyro
Junfang Fan
2013-08-01
Full Text Available The bell-shaped vibratory angular rate gyro (abbreviated as BVG is a novel shell vibratory gyroscope, which is inspired by the Chinese traditional bell. It sensitizes angular velocity through the standing wave precession effect. The bell-shaped resonator is a core component of the BVG and looks like the millimeter-grade Chinese traditional bell, such as QianLong Bell and Yongle Bell. It is made of Ni43CrTi, which is a constant modulus alloy. The exciting element, control element and detection element are uniformly distributed and attached to the resonator, respectively. This work presents the design, analysis and experimentation on the BVG. It is most important to analyze the vibratory character of the bell-shaped resonator. The strain equation, internal force and the resonator's equilibrium differential equation are derived in the orthogonal curvilinear coordinate system. When the input angular velocity is existent on the sensitive axis, an analysis of the vibratory character is performed using the theory of thin shells. On this basis, the mode shape function and the simplified second order normal vibration mode dynamical equation are obtained. The coriolis coupling relationship about the primary mode and secondary mode is established. The methods of the signal processing and control loop are presented. Analyzing the impact resistance property of the bell-shaped resonator, which is compared with other shell resonators using the Finite Element Method, demonstrates that BVG has the advantage of a better impact resistance property. A reasonable means of installation and a prototypal gyro are designed. The gyroscopic effect of the BVG is characterized through experiments. Experimental results show that the BVG has not only the advantages of low cost, low power, long work life, high sensitivity, and so on, but, also, of a simple structure and a better impact resistance property for low and medium angular velocity measurements.
基于LabWindows/CVI的电能质量分析仪%Power Quality Analyzer Based on LabWindows/CVI
陈莉; 张宏立; 张瑞明
2011-01-01
To against the shortcomings of traditional power quality analyzing systems, I. E. , limited storage capacity and monotonous display functions, etc. , the hardware system combines high performance data acquisition module PCL-818H and industrial PC as the core is designed. The system can collect and analyze the real-time signals, in addition, by adopting the powerful test and analysis functions of virtual instrument LabWindows/ C VI, the calculations of phases and amplitudes of fundamental wave and harmonic waves; voltage deviation, distortion rate of active power and reactive power; and software of data storage function are completed. By repeating tests, it is shown that the analyzer features high accuracy, ease to read, reliable operation and high cost effective.%针对传统电能质量分析系统存在存储容量小、显示功能单调等缺点,设计了以高性能数据采集卡PCL-818H与工业控制计算机为核心的硬件系统.该系统对实时信号进行采集与分析,并利用虚拟仪器LabWindows/CVI的强大测试分析功能,完成了基波和谐波的幅值与相位、电压偏差、有功和无功畸变率等参数计算,且具有数据存盘的软件功能.通过反复验证,该分析仪具有精度较高、直观易读、工作可靠和性价比高等特点.
Fourier relationship between angular position and optical orbital angular momentum
Yao, E.; Franke-Arnold, S.; Courtial, J.; Barnett, S.; Padgett, M. J.
2006-01-01
We demonstrate the Fourier relationship between angular position and angular momentum for a light mode. In particular we measure the distribution of orbital angular momentum states of light that has passed through an aperture and verify that the orbital angular momentum distribution is given by the complex Fourier-transform of the aperture function. We use spatial light modulators, configured as diffractive optical components, to define the initial orbital angular momentum state of the beam, ...
Measurements of neutron polarization from (rvec p,rvec n) reactions can provide valuable clues toward understanding the isovector nucleon-nucleus interaction. A neutron time-of-flight polarimeter has been constructed at the Los Alamos Meson Physics Facility to perform such measurements, but before the polarimeter can be used, its effective analyzing powers must be determined. This is accomplished by using the 14C(rvec p,rvec n)14N reaction at a bombarding energy of 494 MeV to produce a beam of neutrons with known polarization, illuminating the detector with these neutrons, and measuring the azimuthal asymmetries after scattering from a hydrogenous analyzer fluid within the detector. Secondary measurements are made using the 2H(rvec p,rvec n)2p reaction with bombarding energies of 318 and 494 MeV to produce a polarized neutron beam. The results from (rvec np) analyzing reactions within the detector agree with values anticipated from free nucleon-nucleon analyzing powers, but the results from (rvec np) analyzing reactions display a more than 33% reduction from the anticipated values. Additionally, measurements are made of the polarization transfer coefficient DLL(0 degree) for rvec p,rvec n Gamow-Teller reactions on 2H, 7Li12C, and 14C targets. For a purely central interaction, one would expect that DLL(0 degree) ∼ -1/3 in the plane wave limit, but a simple average of the Jπ = 0+ → 1+ results at a bombardment energy of 494 MeV gives DLL(0 degree) = -0.689 ± 0.044. Thus, the measurements indicate that the nucleon-nucleus interaction -- which is largely central at 200 MeV -- has strong tensor contributions at higher energy
Jiménez Espadafor, Francisco J.; A. Becerra Villanueva, José; Palomo Guerrero, Daniel; Torres García, Miguel; Carvajal Trujillo, Elisa; Fernández Vacas, Francisco
2014-12-01
This paper presents an investigation into the potential of using direct measurement of engine torque for diagnostic purposes in large engines - in this case applied to power generation. The procedures for measuring and analyzing the instantaneous torque, the angular displacement on the generator output end and the angular displacement on its free end for a ten-cylinder, low speed two stroke diesel engine are presented. Angular speed oscillations are frequently used for combustion engine diagnostics although they cannot be used to measure engine power directly. In addition, and for engines with huge inertia generators such as those used in power plants, speed oscillations are very low and this reduces the signal to noise ratio and makes the evaluation of the instantaneous angular speed very noisy. In the work described here, torque and angular displacement measurements carried out at the same point and with the same engine conditions are compared and the superior performance of torque is demonstrated. Harmonic analysis of instantaneous torque allowed the identification of the dynamic characteristics of the power train of the diesel group and clearly suggests that this signal can be used as a diagnostic tool for excitation, combustion malfunctions, or for the mechanical characteristics of the system and crankshaft stiffness. The torque distortion introduced by the generator due to the discontinuity imposed by the pole pairs is also observed in the torque signal, suggesting that the torque signal can be used to identify generator malfunction.
Estimates of the solar internal angular velocity obtained with the Mt. Wilson 60-foot solar tower
Rhodes, Edward J., Jr.; Cacciani, Alessandro; Woodard, Martin; Tomczyk, Steven; Korzennik, Sylvain
1987-01-01
Estimates are obtained of the solar internal angular velocity from measurements of the frequency splittings of p-mode oscillations. A 16-day time series of full-disk Dopplergrams obtained during July and August 1984 at the 60-foot tower telescope of the Mt. Wilson Observatory is analyzed. Power spectra were computed for all of the zonal, tesseral, and sectoral p-modes from l = 0 to 89 and for all of the sectoral p-modes from l = 90 to 200. A mean power spectrum was calculated for each degree up to 89. The frequency differences of all of the different nonzonal modes were calculated for these mean power spectra.
Fluidic angular velocity sensor
Berdahl, C. M. (Inventor)
1986-01-01
A fluidic sensor providing a differential pressure signal proportional to the angular velocity of a rotary input is described. In one embodiment the sensor includes a fluid pump having an impeller coupled to a rotary input. A housing forming a constricting fluid flow chamber is connected to the fluid input of the pump. The housing is provided with a fluid flow restrictive input to the flow chamber and a port communicating with the interior of the flow chamber. The differential pressure signal measured across the flow restrictive input is relatively noise free and proportional to the square of the angular velocity of the impeller. In an alternative embodiment, the flow chamber has a generally cylindrical configuration and plates having flow restrictive apertures are disposed within the chamber downstream from the housing port. In this embodiment, the differential pressure signal is found to be approximately linear with the angular velocity of the impeller.
Metamaterial broadband angular selectivity
Shen, Yichen; Ye, Dexin; Wang, Li; Celanovic, Ivan; Ran, Lixin; Joannopoulos, John D.; Soljačić, Marin
2014-09-01
We demonstrate how broadband angular selectivity can be achieved with stacks of one-dimensionally periodic photonic crystals, each consisting of alternating isotropic layers and effective anisotropic layers, where each effective anisotropic layer is constructed from a multilayered metamaterial. We show that by simply changing the structure of the metamaterials, the selective angle can be tuned to a broad range of angles; and, by increasing the number of stacks, the angular transmission window can be made as narrow as desired. As a proof of principle, we realize the idea experimentally in the microwave regime. The angular selectivity and tunability we report here can have various applications such as in directional control of electromagnetic emitters and detectors.
Metamaterial Broadband Angular Selectivity
Shen, Yichen; Wang, Zhiyu; Wang, Li; Celanovic, Ivan; Ran, Lixin; Joannopoulos, John D; Soljacic, Marin
2014-01-01
We demonstrate how broadband angular selectivity can be achieved with stacks of one-dimensionally periodic photonic crystals, each consisting of alternating isotropic layers and effective anisotropic layers, where each effective anisotropic layer is constructed from a multilayered metamaterial. We show that by simply changing the structure of the metamaterials, the selective angle can be tuned to a broad range of angles; and, by increasing the number of stacks, the angular transmission window can be made as narrow as desired. As a proof of principle, we realize the idea experimentally in the microwave regime. The angular selectivity and tunability we report here can have various applications such as in directional control of electromagnetic emitters and detectors.
Differential cross sections and analyzing powers have been obtained for the scattering of neutrons from the ground and first excited states of 208Pb. These new measurements include differential cross sections for elastic and inelastic neutron scattering at 8.0 MeV, and analyzing powers for elastic and inelastic neutron scattering at 6.0, 7.0, 8.0, 9.0, and 10.0 MeV. The present elastic scattering data have been combined with the previously measured TUNL data and data measured elsewhere in order to obtain a detailed and high accuracy data set for neutron elastic scattering from 208Pb over the 4.0 to 40.0 MeV energy range. This comprehensive data set has been described using the spherical optical model in which constant geometry fits, energy-dependent geometry fits, and fits incorporating the dispersion relation were performed. Although the overall description of the elastic n+208Pb scattering data was reasonably good using the various optical potentials, small systematic discrepancies remained at the backward angles of both the cross section and analyzing power data, and no optical model solution based on conventional Woods-Saxon form factors was found which could describe all of the details seen in the scattering data. To relax the constraint of having a Woods-Saxon form factor, the real central part of the optical model potential was modified using a Fourier-Bessel expansion of the real central potential. Individual fits at 6.0, 7.0, 8.0, 9.0, and 10.0 MeV, and fits to the combined 6.0 to 10.0 MeV data set were obtained using a Fourier-Bessel expansion of the real central potential and compared to fits using a conventional Woods-Saxon form factor
Deuteron tensor and vector analyzing powers have been measured for the first time in p-d vector elastic scattering at 800 MeV proton laboratory energy for a-t range between 0.032 and 1.038 (GeV/c)2. The data provide a very sensitive test of the multiple scattering theory at intermediate energies. The inclusion of the noneikonal correction in the Glauber diffraction theory is essential in the description of the data, especially for-t approx. >= 0.2(GeV/c)2, where discrepancies of up to 150% are observed with the theory based on the eikonal approximation. (orig.)
Okada, H.; Alekseev, I. G.; Bravar, A; Bunce, G.; Dhawan, S.; Gill, R; Haeberli, W.; Jinnouchi, O.; Khodinov, A.; Makdisi, Y.; Nass, A.; Saito, N; Stephenson, E. J.; D.N. Svirida; Wise, T.
2005-01-01
A precise measurement of the analyzing power $A_N$ in proton-proton elastic scattering in the region of 4-momentum transfer squared $0.001 < |t| < 0.032 ({\\rm GeV}/c)^2$ has been performed using a polarized atomic hydrogen gas jet target and the 100 GeV/$c$ RHIC proton beam. The interference of the electromagnetic spin-flip amplitude with a hadronic spin-nonflip amplitude is predicted to generate a significant $A_N$ of 4--5%, peaking at $-t \\simeq 0.003 ({\\rm GeV}/c)^2$. This kinematic region...
The tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with a momentum of 4.5 GeV/c on beryllium at an angle of ∝80 mr in the vicinity of baryonic resonance excitation have been measured. The Ayy data being in good agreement with the previous results obtained at a zero angle demonstrate an approximate t scaling up to ∝-0.9 (GeV/c)2. The results of the experiment are compared with the predictions of the multiple-scattering and ω-meson exchange models. (orig.)
Essén, H
2003-01-01
This paper addresses the problem of the separation of rotational and internal motion. It introduces the concept of average angular velocity as the moment of inertia weighted average of particle angular velocities. It extends and elucidates the concept of Jellinek and Li (1989) of separation of the energy of overall rotation in an arbitrary (non-linear) $N$-particle system. It generalizes the so called Koenig's theorem on the two parts of the kinetic energy (center of mass plus internal) to three parts: center of mass, rotational, plus the remaining internal energy relative to an optimally translating and rotating frame.
Jankowiak, Martin; Larkoski, Andrew J.; /SLAC
2012-02-17
We introduce a jet shape observable defined for an ensemble of jets in terms of two-particle angular correlations and a resolution parameter R. This quantity is infrared and collinear safe and can be interpreted as a scaling exponent for the angular distribution of mass inside the jet. For small R it is close to the value 2 as a consequence of the approximately scale invariant QCD dynamics. For large R it is sensitive to non-perturbative effects. We describe the use of this correlation function for tests of QCD, for studying underlying event and pile-up effects, and for tuning Monte Carlo event generators.
Orbital angular momentum from marginals of quadrature distributions
Sanchez-Soto, L. L.; Klimov, A. B.; de la Hoz, P.; Rigas, I.; J. Rehacek; Hradil, Z.; Leuchs, G.
2013-01-01
We set forth a method to analyze the orbital angular momentum of a light field. Instead of using the canonical formalism for the conjugate pair angle-angular momentum, we model this latter variable by the superposition of two independent harmonic oscillators along two orthogonal axes. By describing each oscillator by a standard Wigner function, we derive, via a consistent change of variables, a comprehensive picture of the orbital angular momentum. We compare with previous approaches and show...
Probabilistic calculation for angular dependence collision
This collision probabilistic method is broadly used in cylindrical geometry (in one- or two-dimensions). It constitutes a powerful tool for the heterogeneous Response Method where, the coupling current is of the cosine type, that is, without angular dependence at azimuthal angle θ and proportional to μ (cosine of the θ polar angle). (Author)
A neutron-number (N) dependence of analyzing powers A (theta) has been observed for the first time in (polarized p, t) reactions leading to the quadrupole vibrational states (21+) in 98Ru, sup(102,108)Pd, 114Cd, 116Sn, and sup(120,126)Te. Although analyzing powers for the ground-state transitions A(theta,0 sub(g)sup(+)) are very similar to each other, those for the 21+ transitions A(theta,21+) for the nuclei belonging to the beginning of the N = 50 - 82 shell are markedly different, having almost opposite signs, from A(theta,21+) for nuclei belonging to the latter half of the major shell. The difference is explained as a result of a sign change of the interference between one- and inelastic multi-step processes in two-neutron pickup reactions. Nuclear structure effects on such an interference are discussed on the basis of the microscopic description of collective quadrupole oscillation of nuclei. (author)
Analyzed Using Statistical Moments
Diffraction enhanced imaging (DEl) technique is a new x-ray imaging method derived from radiography. The method uses a monorheumetten x-ray beam and introduces an analyzer crystal between an object and a detector Narrow angular acceptance of the analyzer crystal generates an improved contrast over the evaluation radiography. While standart radiography can produce an 'absorption image', DEl produces 'apparent absorption' and 'apparent refraction' images with superior quality. Objects with similar absorption properties may not be distinguished with conventional techniques due to close absorption coefficients. This problem becomes more dominant when an object has scattering properties. A simple approach is introduced to utilize scattered radiation to obtain 'pure absorption' and 'pure refraction' images
Vector analyzing powers A(theta) and differential cross sections σ(theta) have been measured, with the use of a polarized proton beam of 22.0 MeV and a magnetic spectrograph, for (p,t) reactions leading to the first-excited 2+ (21+) states of the following eighteen nuclei of N = 50 - 82: sup(92,94,96)Mo, sup(98,100,102)Ru, sup(102,104,106,108)Pd, sup(110,112,114)Cd, 116Sn, sup(120,126,128)Te, and 136Ba. In addition A(theta) and σ(theta) for sup(104,110)Pd(p,t) sup(102,108) Pd(0sub(g)+,21+) transitions have been measured at Esub(p) = 52.2 MeV. The experimental results are analyzed in terms of the first- and second-order DWBA including both inelastic two-step processes and sequential transfer (p,d)(d,t) two-step processes. Inter-ference effect between the direct and the two-step processes is found to play an essential role in the (p,t) reactions. A sum-rule method for calculating the (p,d)(d,t) spectroscopic amplitudes has been developed so as to take into account the ground-state correlation in odd-A nuclei. The nuclear-structure wave functions are constructed under the boson expansion method and the quasiparticle random phase approximation (qp RPA) method by using the monopole-pairing, quadrupole-pairing, and QQ forces. The characteristic features of the experimental A(theta) and σ(theta) are better explained in terms of the boson expansion method than in terms of the qp RPA. Dependence of the (p,t) analyzing powers on the static electric quadrupole moment of the 21+ state is found to be strong because of the reorientation (anharmonic) effect in the 21+ yiedls 21+ transfer process. (J.P.N.)
Benner, William H.
1986-01-01
An oxygen analyzer which identifies and classifies microgram quantities of oxygen in ambient particulate matter and for quantitating organic oxygen in solvent extracts of ambient particulate matter. A sample is pyrolyzed in oxygen-free nitrogen gas (N.sub.2), and the resulting oxygen quantitatively converted to carbon monoxide (CO) by contact with hot granular carbon (C). Two analysis modes are made possible: (1) rapid determination of total pyrolyzable oxygen obtained by decomposing the sample at 1135.degree. C., or (2) temperature-programmed oxygen thermal analysis obtained by heating the sample from room temperature to 1135.degree. C. as a function of time. The analyzer basically comprises a pyrolysis tube containing a bed of granular carbon under N.sub.2, ovens used to heat the carbon and/or decompose the sample, and a non-dispersive infrared CO detector coupled to a mini-computer to quantitate oxygen in the decomposition products and control oven heating.
The angular dependence of the tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with a momentum of 9.0 GeV/c on hydrogen and carbon has been measured. The range of measurements corresponds to the baryonic resonance excitation with masses of ∼2.2-2.6 GeV/c2. The Ayy data, being in good agreement with the previous results, demonstrate an approximate t scaling up to -1.5 (GeV/c)2. The large values of Ay show a significant role of the spin-dependent part of the elementary amplitude of the NN → NN* reaction. The results of the experiment are compared with model predictions of the plane-wave impulse approximation
Analyzing power in inclusive π+ and π- production at high xF with a 200 GeV polarized proton beam
The analyzing power in inclusive charged pion production has been measured using the 200 GeV Fermilab polarized proton beam. A striking dependence in χF is observed in which AN increases from 0 to 0.42 with increasing χF for the π+ data and decreases from 0 to -0.38 with increasing χF for π- data. The kinematic range covered is 0.2≤χF≤0.9 and 0.2≤pT≤2.0 GeV/c. In a simple model our data indicate that at large χF the transverse spin of the proton is correlated with that of its quark constituents. (orig.)
Investigation of the tensor analyzing power t{sub 20} in the reaction d{sup →} +p → {sup 3}He + η
Papenbrock, Michael; Fritzsch, Christopher; Goslawski, Paul; Khoukaz, Alfons; Mielke, Malte; Schroeer, Daniel; Taeschner, Alexander [Westfaelische Wilhelms-Universitaet, Muenster (Germany); Collaboration: ANKE-Collaboration
2013-07-01
Previous measurements on the reaction d{sup →} +p → {sup 3}He + η with the ANKE spectrometer at the COoler SYnchrotron - COSY - of the Forschungszentrum Juelich provided strong indications for the existence of a quasi-bound state of the η-{sup 3}He system. In order to gather more evidence for this possible quasi-bound state, measurements with a polarized deuteron beam have been performed at ANKE on the reaction d{sup →} +p → {sup 3}He + η. Hence, the investigation of the energy dependence of the tensor analyzing power t{sub 20} allows to study in more detail the role of the final state interaction in the strong enhancement of the total cross section. Recent results are presented and discussed. Furthermore, a brief outlook on the upcoming measurement on the reaction p+n → d+η in the context of η-mesic nuclei is given.
Tensor Ayy and vector Ayy analyzing powers of inelastic scattering of deuterons with momentum of 4.5 GeV/c on beryllium at and angle of ∼ 80 mrad in the vicinity of baryonic resonance excitation have been measured. The new Ayy data being plotted versus t are in good agreement with the previous data at 4/5, 5.5, and 9 GeV/c, obtained at zero angle in an overlapping region of t, and all existing data fit the common |t| dependence up to ∼ 0.9 (GeV/c)2. The results of the experiment are compared with the calculations in the framework of the multiple-scattering and ω-meson exchange models in t-channel
Angular momentum projected semiclassics
Hasse, Rainer W.
1987-06-01
By using angular momentum projected plane waves as wave functions, we derive semiclassical expressions for the single-particle propagator, the partition function, the nonlocal density matrix, the single-particle density and the one particle-one hole level density for fixed angular momentum and fixed z-component or summed over the z-components. Other quantities can be deduced from the propagator. In coordinate space ( r, r') the relevant quantities depend on |r-r'| instead of | r- r'| and in Wigner space ( R, P) they become proportional to the angular momentum constraints δ(| R × P|/ h̵-l) and δ( R × P) z/ h̵-m) . As applications we calculate the single-particle and one-particle-one hole level densities for harmonic oscillator and Hill-Wheeler box potentials and the imaginary part of the optical potential and its volume integral with an underlying harmonic oscillator potential and a zero range two-body interaction.
Chirality and angular momentum in optical radiation
Coles, Matt M
2012-01-01
This paper develops, in precise quantum electrodynamic terms, photonic attributes of the "optical chirality density", one of several measures long known to be conserved quantities for a vacuum electromagnetic field. The analysis lends insights into some recent interpretations of chiroptical experiments, in which this measure, and an associated chirality flux, have been treated as representing physically distinctive "superchiral" phenomena. In the fully quantized formalism the chirality density is promoted to operator status, whose exploration with reference to an arbitrary polarization basis reveals relationships to optical angular momentum and helicity operators. Analyzing multi-mode beams with complex wave-front structures, notably Laguerre-Gaussian modes, affords a deeper understanding of the interplay between optical chirality and optical angular momentum. By developing theory with due cognizance of the photonic character of light, it emerges that only the spin angular momentum of light is engaged in such...
Chien, T.H.; Domanus, H.M.; Sha, W.T.
1993-02-01
The COMMIX-PPC computer program is an extended and improved version of earlier COMMIX codes and is specifically designed for evaluating the thermal performance of power plant condensers. The COMMIX codes are general-purpose computer programs for the analysis of fluid flow and heat transfer in complex industrial systems. In COMMIX-PPC, two major features have been added to previously published COMMIX codes. One feature is the incorporation of one-dimensional conservation of mass. momentum, and energy equations on the tube side, and the proper accounting for the thermal interaction between shell and tube side through the porous medium approach. The other added feature is the extension of the three-dimensional conservation equations for shell-side flow to treat the flow of a multicomponent medium. COMMIX-PPC is designed to perform steady-state and transient three-dimensional analysis of fluid flow with heat transfer in a power plant condenser. However, the code is designed in a generalized fashion so that, with some modification. it can be used to analyze processes in any heat exchanger or other single-phase engineering applications.
Angular dispersion and energy loss of H+ and He+ in metals
In this master thesis the effects produced when a light ion beam traverses a thin metallic film were studied.In particular, the interactions of low energy (E ≤ 10 keV) light ions (H+,H2+, D+, He+) with monocrystalline and also polycrystalline gold samples were investigated.In first place, the dependence of the stopping power with projectiles' velocity was studied, analyzing the threshold effect in the excitation of the 5d electrons in the channelling regime for energies between 0,4 and 9 keV.Next, the angular dispersion of ions in polycrystalline and monocrystalline films was measured and analyzed.Comparisons for different energies and projectiles were done, studying molecular and isotopic effects.Using Lindhard's channeling theory, a scale law for the angular dispersion of angles greater than the critical angle was found.Additionally, the angular dependence of the energy loss and the energy loss straggling of protons transmitted through monocrystals were measured.To explain the angular variations of these magnitudes a theoretical model based on the electronic density fluctuations inside the channel was developed
DISTRIBUTION OF ACCRETING GAS AND ANGULAR MOMENTUM ONTO CIRCUMPLANETARY DISKS
We investigate gas accretion flow onto a circumplanetary disk from a protoplanetary disk in detail by using high-resolution three-dimensional nested-grid hydrodynamic simulations, in order to provide a basis of formation processes of satellites around giant planets. Based on detailed analyses of gas accretion flow, we find that most of gas accretion onto circumplanetary disks occurs nearly vertically toward the disk surface from high altitude, which generates a shock surface at several scale heights of the circumplanetary disk. The gas that has passed through the shock surface moves inward because its specific angular momentum is smaller than that of the local Keplerian rotation, while gas near the midplane in the protoplanetary disk cannot accrete to the circumplanetary disk. Gas near the midplane within the planet's Hill sphere spirals outward and escapes from the Hill sphere through the two Lagrangian points L1 and L2. We also analyze fluxes of accreting mass and angular momentum in detail and find that the distributions of the fluxes onto the disk surface are well described by power-law functions and that a large fraction of gas accretion occurs at the outer region of the disk, i.e., at about 0.1 times the Hill radius. The nature of power-law functions indicates that, other than the outer edge, there is no specific radius where gas accretion is concentrated. These source functions of mass and angular momentum in the circumplanetary disk would provide us with useful constraints on the structure and evolution of the circumplanetary disk, which is important for satellite formation.
Quark Orbital Angular Momentum
Burkardt, Matthias
2016-06-01
Generalized parton distributions provide information on the distribution of quarks in impact parameter space. For transversely polarized nucleons, these impact parameter distributions are transversely distorted and this deviation from axial symmetry leads on average to a net transverse force from the spectators on the active quark in a DIS experiment. This force when acting along the whole trajectory of the active quark leads to transverse single-spin asymmetries. For a longitudinally polarized nucleon target, the transverse force implies a torque acting on the quark orbital angular momentum (OAM). The resulting change in OAM as the quark leaves the target equals the difference between the Jaffe-Manohar and Ji OAMs.
Quark Orbital Angular Momentum
Burkardt, Matthias
2016-03-01
Generalized parton distributions provide information on the distribution of quarks in impact parameter space. For transversely polarized nucleons, these impact parameter distributions are transversely distorted and this deviation from axial symmetry leads on average to a net transverse force from the spectators on the active quark in a DIS experiment. This force when acting along the whole trajectory of the active quark leads to transverse single-spin asymmetries. For a longitudinally polarized nucleon target, the transverse force implies a torque acting on the quark orbital angular momentum (OAM). The resulting change in OAM as the quark leaves the target equals the difference between the Jaffe-Manohar and Ji OAMs.
Vanston, Alex
2013-01-01
This book uses a practical, step-by-step approach, starting with how to build directives from the ground up before moving on to creating web applications comprised of multiple modules all working together to provide the best user experience possible.This book is intended for intermediate JavaScript developers who are looking to enhance their understanding of single-page web application development with a focus on AngularJS and the JavaScript MVC frameworks.It is expected that readers will understand basic JavaScript patterns and idioms and can recognize JSON formatted data.
Nonzero orbital angular momentum superfluidity in ultracold Fermi gases
Iskin, M.; de Melo, C. A. R. Sá
2006-01-01
We analyze the evolution of superfluidity for nonzero orbital angular momentum channels from the Bardeen-Cooper-Schrieffer (BCS) to the Bose-Einstein condensation (BEC) limit in three dimensions. First, we analyze the low energy scattering properties of finite range interactions for all possible angular momentum channels. Second, we discuss ground state ($T = 0$) superfluid properties including the order parameter, chemical potential, quasiparticle excitation spectrum, momentum distribution, ...
Highlights: ► Wind speed and insolation period data were analyzed using a data mining approach. ► Most of the studies in the literature were based on Weibull and Rayleigh models. ► Nearest and farest neighbor algorithms were used with different distance metrics. ► Many inferences were achieved in efficient limits for wind and solar farm analyses. - Abstract: Wind and solar power plant installations have been recently increased rapidly with respect to the depletion of fossil-based fuels all over the world. Due to stochastic nature of meteorological conditions, wind and solar energies have a non-schedulable nature and they require several installation analyses to determine the location and the capacities of wind and solar power to be produced. This paper focuses on the similarity, feasibility and numerical analyses of 75 cities in Turkey based on the monthly average wind speed and insolation period data. The nearest and the farest neighbor algorithms are used as agglomerative hierarchical clustering methods with Euclidean, Manhattan and Minkowski distance metrics in the stage of making the similarity and feasibility analyses. The maximum cophenetic correlation coefficient is achieved by the nearest neighbor algorithm with the Minkowski distance metric in the similarity and feasibility analyses. On the other hand, graphical representations of the monthly average wind speed and insolation period data are utilized for making the numerical analysis. The highest annual average wind speed and insolation period are obtained as 3.88 m/s and 8.45 h/day, respectively. Overall, many inferences were achieved in acceptable and efficient limits for wind and solar energy.
The A4 experiment determines the strange quark contribution to the electromagnetic from factors of the nucleon by measuring the parity violation in elastic electron nucleon scattering. These measurements are carried out using the spin polarized electron beam of the Mainzer Mikrotron (MAMI) with beam energies in the range from 315 to 1508 MeV. For the data analysis it is essential to determine the degree of polarization of the electron beam in order to extract the physics asymmetry from the measured parity violating asymmetry. For this reason the A4 collaboration has developed a novel type of Compton laser backscattering polarimeter that allows for a non-destructive measurement of the beam polarization in parallel to the running parity experiment. In the scope of this work the polarimeter was refined in order to enable reliable continuous operation of the polarimeter. The data acquisition system for the photon and electron detector was re-designed and optimized to cope with high count rates. A novel detector (LYSO) for the backscattered photons was commissioned. Furthermore, GEANT4 simulations of the detectors have been performed and an analysis environment for the extraction of Compton asymmetries from the backscattered photon data has been developed. The analysis makes use of the possibility to detect backscattered photons in coincidence with the scattered electrons, thus tagging the photons. The tagging introduces a differential energy scale which enables the precise determination of the analyzing power. In this work the analyzing power of the polarimeter has been determined. Therefore, at a beam current of 20 μA the product of electron and laser polarization can be determined, while the parity experiment is running, with a statistical accuracy of 1 % in 24 hours at 855 MeV or 2=0.6 (GeV/c)2 the analysis yields a raw asymmetry of ARohPV=(-20.0±0.9stat) x 10-6 at the moment. For a beam polarization of 80 % the total error would be 1,68 x 10-6 with ΔPe/Pe=5
Okada, H. [Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); RIKEN, Wako, Saitama 351-0198, (Japan); Alekseev, I.G. [Institute for Theoretical and Experimental Physics, 117259 Moscow (Russian Federation); Bravar, A. [Brookhaven National Laboratory, Upton, NY 11973 (United States)]. E-mail: bravar@bnl.gov; Bunce, G. [Brookhaven National Laboratory, Upton, NY 11973 (United States); RIKEN BNL Research Center, Upton, NY 11973 (United States); Dhawan, S. [Yale University, New Haven, CT 06520 (United States); Gill, R. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Haeberli, W. [Stony Brook University, Stony Brook, NY 11794 (United States); Jinnouchi, O. [RIKEN BNL Research Center, Upton, NY 11973 (United States); Khodinov, A. [Stony Brook University, Stony Brook, NY 11794 (United States); Makdisi, Y. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Nass, A. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Saito, N. [Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan); RIKEN, Wako, Saitama 351-0198 (Japan); Stephenson, E.J. [Indiana University Cyclotron Facility, Bloomington, IN 47408 (United States); Svirida, D.N. [Institute for Theoretical and Experimental Physics, 117259 Moscow (Russian Federation); Wise, T. [University of Wisconsin, Madison, WI 53706 (United States); Zelenski, A. [Brookhaven National Laboratory, Upton, NY 11973 (United States)
2006-07-20
Precise measurement of the analyzing power A{sub N} in proton-proton elastic scattering in the region of 4-momentum transfer squared 0.001< vertical bar t vertical bar <0.032 (GeV/c){sup 2} has been performed using a polarized atomic hydrogen gas jet target and the 100 GeV/c RHIC proton beam. The interference of the electromagnetic spin-flip amplitude with a hadronic spin-nonflip amplitude is predicted to generate a significant A{sub N} of 4-5%, peaking at -t{approx}0.003 (GeV/c){sup 2}. This kinematic region is known as the Coulomb nuclear interference region. A possible hadronic spin-flip amplitude modifies this calculable prediction. We present the first precise result of the CNI asymmetry and shape as a function of t. Our data are well described by the CNI prediction with the electromagnetic spin-flip alone and do not support the presence of a large hadronic spin-flip amplitude.
Measurements of the unpolarized triple differential cross section and the Ayy tensor analyzing power for the 1H(d,pp)n reaction were made using a 94.5 MeV polarized deuteron beam at the Indiana University Cyclotron Facility. Scattering angles (θ and φ) and energy information were recorded for the two emerging protons using large-area wire chambers backed by stopping plastic scintillator detectors. Events were selected that were close to the symmetric constant relative energy geometry in order to enhance the sensitivity of the observables to off-shell and three-body effects. The measurements covered values of α, the center-of-mass angle between the incoming proton and the outgoing neutron, from 72 degree to 180 degree. Comparisons are made to Faddeev calculations that use either separable potentials or an exact treatment of the S-wave nucleon-nucleon interaction in conjunction with a perturbative treatment of higher partial waves. While none of these calculations, which use only two-nucleon interactions, is completely satisfactory, there remains too much variation among different theoretical treatments to demonstrate the need for including additional dynamical features in the three-body model
Clustering, Angular Size and Dark Energy
R.C. Santos; Lima, J. A. S.
2008-01-01
The influence of dark matter inhomogeneities on the angular size-redshift test is investigated for a large class of flat cosmological models driven by dark energy plus a cold dark matter component (XCDM model). The results are presented in two steps. First, the mass inhomogeneities are modeled by a generalized Zeldovich-Kantowski-Dyer-Roeder (ZKDR) distance which is characterized by a smoothness parameter $\\alpha(z)$ and a power index $\\gamma$, and, second, we provide a statistical analysis t...
γ - γ Angular Correlation Measurements With GRIFFIN
Maclean, Andrew; Griffin Collaboration
2015-10-01
When an excited nuclear state emits successive γ-rays causing a γ - γ cascade an anisotropy is found in the spatial distribution of γ2 with respect to γ1. Defining the direction of γ1 as the z-axis, the intermediate level, in general will have an uneven distribution of m-states. This causes an anisotropy in the angular correlation of the second γ-ray with respect to the first. These angular correlations are expressed by the W (θ) that depends on numerical coefficients described by the sequence of spin-parity values for the nuclear states involved, the multipolarities and mixing ratios. Angular correlations can be used for the assignment of spins and parities for the nuclear states, and thus provide a powerful means to elucidate the structure of nuclei far from stability through β - γ - γ coincidence measurements. In order to explore the sensitivity of the new 16 clover-detector GRIFFIN γ-ray spectrometer at TRIUMF-ISAC to such γ - γ angular correlations, and to optimize its performance for these measurements we have studied a well known γ - γ cascade from 60Co decay through both experimental measurements and Geant4 simulation. Results will be shown in this talk. Work supported by the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada and the National Research Council of Canada.
Orbital angular momentum microlaser
Miao, Pei; Zhang, Zhifeng; Sun, Jingbo; Walasik, Wiktor; Longhi, Stefano; Litchinitser, Natalia M.; Feng, Liang
2016-07-01
Structured light provides an additional degree of freedom for modern optics and practical applications. The effective generation of orbital angular momentum (OAM) lasing, especially at a micro- and nanoscale, could address the growing demand for information capacity. By exploiting the emerging non-Hermitian photonics design at an exceptional point, we demonstrate a microring laser producing a single-mode OAM vortex lasing with the ability to precisely define the topological charge of the OAM mode. The polarization associated with OAM lasing can be further manipulated on demand, creating a radially polarized vortex emission. Our OAM microlaser could find applications in the next generation of integrated optoelectronic devices for optical communications in both quantum and classical regimes.
Orbital angular momentum microlaser.
Miao, Pei; Zhang, Zhifeng; Sun, Jingbo; Walasik, Wiktor; Longhi, Stefano; Litchinitser, Natalia M; Feng, Liang
2016-07-29
Structured light provides an additional degree of freedom for modern optics and practical applications. The effective generation of orbital angular momentum (OAM) lasing, especially at a micro- and nanoscale, could address the growing demand for information capacity. By exploiting the emerging non-Hermitian photonics design at an exceptional point, we demonstrate a microring laser producing a single-mode OAM vortex lasing with the ability to precisely define the topological charge of the OAM mode. The polarization associated with OAM lasing can be further manipulated on demand, creating a radially polarized vortex emission. Our OAM microlaser could find applications in the next generation of integrated optoelectronic devices for optical communications in both quantum and classical regimes. PMID:27471299
Measuring angular diameter distances of strong gravitational lenses
Jee, Inh; Suyu, Sherry H
2014-01-01
The distance-redshift relation plays a fundamental role in constraining cosmological models. In this paper, we show that measurements of positions and time delays of strongly lensed images of a background galaxy, as well as those of the velocity dispersion and mass profile of a lens galaxy, can be combined to extract the angular diameter distance of the lens galaxy. Physically, as the velocity dispersion and the time delay give a gravitational potential ($GM/r$) and a mass ($GM$) of the lens, respectively, dividing them gives a physical size ($r$) of the lens. Comparing the physical size with the image positions of a lensed galaxy gives the angular diameter distance to the lens. A mismatch between the exact locations at which these measurements are made can be corrected by measuring a local slope of the mass profile. We expand on the original idea put forward by Paraficz and Hjorth, who analyzed singular isothermal lenses, by allowing for an arbitrary slope of a power-law spherical mass density profile, an ex...
Authors presents an educational laboratory Safety and Control of a Nuclear Power Facility established by the Department of Automation for students and specialists of the nuclear power industry in the field of control, protection, and safe exploitation of reactor facilities at operating, constructing, and designing nuclear power plants with water-moderated water-cooled reactors